Official Journal of International Quarterly Publication ISSN 1608-2281 Original Journal Name: Asian Journal of Drug Metabolism and Pharmacokinetics (2001-2005)

亞洲藥效動力學與藥物代謝動力學雜誌

Asian Journal of Pharmacodynamics and Pharmacokinetics

Academic Editor-in-Chief Chang-Xiao Liu and Yuichi Sugiyama

Volume 9 Number 3 September 2009

Hong Kong Medical Publisher

香 港 醫 藥 出 版 社

Asian Journal of Pharmacodynamics and Pharmacokinetics

An International Quarterly Publication ISSN 1608-2281 NR 3880/169/00

http://www.hktmc.com/ChineseMedia/Magazine/Medicine/ajdmpk

Publisher President

Kwong Cheung Ku Hong Kong Medical Publisher 24/F Yuen Long Trading Center, 99-109 Castle Peak Road, Yuen Long, Hong Kong, China

Academic Editor-in-chief

Chang-Xiao Liu Tianjin Institute of Pharmaceutical Research, 308 An-Shan West Road, Tianjin 300193, China Yuichi Sugiyama Department of Molecular Pharmacokinetics, The University of Tokyo, Tokyo, 113-0033, Japan

Assistant Academic Editor-in-Chief

Da-Fang Zhong Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 646 Songtao Road Shanghai, 201203, China Guang-Hua Du Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, 100050, China Qiang Zhang School of Pharmaceutical Sciences, Peking University, Beijing, 100083, China

Publishing Editor-in-chief

Annie Ning Editor-in-chief of Hong Kong Medical Publisher Hui Qing Shi Vice-editor-in-chief of Hong Kong Medical Publisher

Members of Editorial Committee Henning H. Blume (Oberursel,

GERMANY)

Zheng-Min Chen (Tianjin, CHINA) Moses SS Chow (Hong Kong, CHINA) Guang-Hua Du (Beijing, CHINA) Paul Fawcett (Otago, NEW ZEALAND) Jack Gao (Carborough, CANADA) Mei-Yu Geng (Qingdao，CHINA） Patrick M. Gennissel (Paris, FRANCE) Kun Han (Chungbuk, KOREA) Guo-Zhu Han (Dalian, CHINA) Pei Hu (Beijing, CHINA) Zhuo-Han Hu (Shanghai, CHINA) Xi Huang (Changsha, CHINA) Jun-Yan Hong (New Jersey, USA) Li-Ya Ju (Charenton le Pont, FRANCE) Devarakonda R. Krishna (Kakatiya,

INDIA) June Lee (NIH, USA) Jian-Guo Li (Wilmington, USA) Lin-Lin Li (Xinjiang, CHINA) Zhi-Bin Lin (Beijing, CHINA)

Terry D. Lindstrom (Indiana, USA) Chang-Xiao Liu (Tianjin, CHINA) Xiao-Dong Liu (Nanjing, CHINA) Ke-Xin Liu (Dalian, CHINA) Jian-Shi Lou (Tianjin, CHINA) Takeo Murakawa (Osaka, JAPAN) Terumichi Nakagawa (Kyoto, JAPAN) Charles H. Nightingale (Hartford, USA) Inotsume Nobuo (Hokkaido, JAPAN) Richard ZM Qian (Hong Kong, CHINA) Madhubala Rentala (New Delhi,

INDIA) Jin-Xiu Ruan (Beijing, CHINA) Guo-Wei Sang (Beijing, CHINA) Xiang-Guo Shi (Boston, USA) Duan-Yun Si (Tianjin, CHINA) Chang Koo Shim (Seoul, KOREA) Yuichi Sugiyama (Tokyo, JAPAN) Ding-Feng Su (Shanghai, CHINA) Nikolaus Sucher (Hong Kong, CHINA) Yong-Da Sun (Bradford, UK) Hui-Qing Shi (Hong Kong, CHINA)

Chang-Koo Shim (Seoul, KOREA) Guang-Ji Wang (Nanjing, CHINA) Hui Wang (Wuhan, CHINA) Ming-Wei Wang (Shanghai, CHINA) Zhi-Min Wang (Beijing, CHINA) Yi-Tao Wang (Macau, CHINA) Guang-Li Wei (Tianjin, CHINA) Chun-Fu Wu (Shenyang，CHINA) Jinn Wu (New Jersey, USA) Fu-Ming Xie ( Indiana, USA) Guo-Wang Xu (Dalian, CHINA) Ming Xue (Beijing, CHINA) Bao-Feng Yang (Harbin，CHINA) Zong-Hui Yuan (Wuhan, CHINA) Fan-Dian Zeng (Wuhan, CHINA) Su Zeng (Hangzhou, CHINA) Qiang Zhang (Beijing, CHINA) Jiang Zheng (Seattle，USA) Da-Fang Zhong (Shanghai, CHINA) Hong-Hao Zhou (Changsha, CHINA) Yao-Wei Zhu (PA, USA) Zhu Zhu (Beijing, CHINA)

162

Asian Journal of Pharmacodynamics and Pharmacokinetics (An International Quarterly Publication)

Volume 9 Number 3 September 2009

Content

Special Repart 163 Attention to Forum on Traditional Chinese Medicine Development at BioEco 2009 168 Strategies for revitalization of traditional alternative and complementary medicine with international

cooperation

Review Papers 169 Nuggehally R Srinivas. Recent research trends in intranasal therapeutics – Select case studies of

various therapeutic strategies with pharmacokinetic/pharmacodynamic attributes and drug development considerations

179 Yan-Yan Xu, Duan-Yun Si, Chang-Xiao Liu. Research on bioresponse of active compounds of Strychnos nux-vomica L.

Research Papers 203 Xin He, Mitsuru Sugawara, Xin-Bing Zhu, Shota Kadomura, Yoh Takekuma3, Chang-Xiao Liu.

Application of an in vitro dissolution and absorption system to evaluate oral absorption of Ketoprofen and Two Preparations of Ketoprofen

211 Hui-Rong Fan, Yuan-Yuan Xia, Chang-Xiao Liu, Duan-Yun Si. Establishment of a liquid chromatographic tandem mass spectrometry method for quantification of carboplatin in rat plasma and its application to a pharmacokinetic study

221 Shi-Jun Zhang, Jing Gao, Ying Huang, and Wei-Ren Xu. Study on the Pharmacokinetics of Fasudil, a selective Rho kinase inhibitor

227 Shao-Jun Shi, Zhong-Fang Li, Yuan-Sheng Wan, Hua-Ting Chen, Fan-Dian Zeng. Pharmacokinetics and relative bioavailability of a novel immunosuppressant -mycophenolate mofetil in healthy Chinese volunteers

233 Shou-Cheng Pu, Yuan-Qiang Guo, Wen-Yuan Gao, Shu-Li Man, Chang-Xiao Liu, Pei-Gen Xiao. Secondary metabolites and biosynthetic pathway approach in medicinal plant Centipeda minima

Information and News 202 Publication News Chinese Herbal Medicines 202 Publication News Drug Evaluation Research 239 Tianjin Centre for Drug Safety Evaluation and Research 240 Name list of China National Science Technology Foundations 240 Publication News: Chinese Medicine

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

163

Asian Journal of

Pharmacodynamics and Pharmacokinetics

ISSN 1608-2281

Copyright by Hong Kong Medical Publisher Publisher Homepage: www.hktmc.com

Special Report Attention to Forum on Traditional Chinese Medicine Development at BioEco 2009 Introduction to BioEco 2009

BioEco 2009, initiated and sponsored by

Ministry of Science and Technology, P. R. China and Tianjin Municipal People’s Government and cosponsored by many other departments of China, international organizations and European Commission, was held at Binhai International Conference & Exhibition Centre, Tianjin, China, on June 26-28, 2009. As the conference of highest authority, highest standard and largest scale so far in china in bioeconomy industry, 2009 International Conference for Bioeconomy will become an international bioeconomy forum which shares the equal brilliant reputation with BIO Annual International Convention and BioVision. A Series of events will be held on the topic of “Develop Bioeconomy, Tackle Financial Crisis”, including: (1) Opening Ceremony of BioEco 2009: Governmental high-level officials, famous scholars and enterprisers will be invited to give keynote speech. (2) Sessions: There are eleven sessions: Government Forum, Life Science and Frontier of Biotechnology, Bioagriculture, Biomedicine, Traditional Chinese Medicine Development, Medical Devices, Industrial and Environmental Biotechnology, Bioenergy, Bioresource and Biodiversity, Chemistry Drug and Drug-safety and Bioindustry Forum. 250 domestic

and foreign experts will make profound discussion on popular and significant issues on biotechnology and industrial development. (3) BioPartnering China: The purpose of BioPartnering China is to promote the international status of China in the worldwide biotechnology industry by communicating with foreign companies and experts. And (4) Exhibition: The exhibition is divided into Medicine Exhibition and Biotechnology Exhibition, covering an area of 40,000m2. The number of visitors reached as high as 80,000 person/time. Exclusive Exhibition Area is prepared in the exhibition for companies from Tianjin.

Topics of Forums

Session 1 Policy Forum: Global Biotechnology macro management-policy, focus of cutting-edge technology, dynamic and trend of industrial development, technological innovation, law and ethic problem of Biotechnology, risk investment and trade.

Session 2 Life Science and Frontier of Biotechnology: Genomics, proteomics, systems biology, brain and cognitive science, involved in basic and advanced situation and trends relating to BT development

Develop Bioeconomy Tackle Financial Crisis

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

164

Session 3 Bioagriculture: Latest break- throughs and trends in the research of transgenic plants, super hybrid rice, embryo transfer, cloning technology, bio-fertilizer, bio-pesticide, bio-degradable plastic film, Avian influenza & veterinary vaccine, veterinary bio-drug, animal hormone, new feed additive, etc Session 4 Biomedicine: Latest breakthroughs and trends in the prevention and treatment of different kinds of diseases and the research of bio-pharma, bio-chip, genetic diagnostic, gene therapy, stem cell, tissue (organ) engineering, etc. Session 5 Traditional Chinese Medicine Development: International standard of Chinese Medicine, biological basis for Chinese medical diagnosis, substantial basis and match of Chinese medicine, promote Chinese Medicine product come into market, development of industry of Traditional Chinese Medicine in international medicine field. Session 6 Prevention and Intervention Technology of Critical Diseases and other Diseases: Key technology of diagnosis and treatment of critical diseases and other diseases, screening, prevention and treatment technology of infectious diseases. Research and development of biomedicine engineering product. Session 7 Industrial and Environmental Biotechnology: Biotechnology situation and trends involved in Food, Feed, Chemistry, Plastic, Weave and Paper Making Industry. Session 8 Bioenergy: Latest breakthroughs and trends in the research of fuel alcohol, bio-diesel, hydrogen bio-production, biogas technology, bio-oil, bio-mining, oil plant variety, fuel wood variety, etc. Session 9 Bioresource and Biodiversity: Biotechnology involved in the treatment wastewater and organic garbage, and latest breakthroughs and trends in the research of salt-drought-tolerant grass and tree, saline-alkaline ponds improvement, eco-environment. Session 10 Chemistry Drug and Drug-safety: Important and urgent problems facing the whole process such as medical industry, drug-safety, drug development, manufactory, trade and clinical application etc. Status and trend faced to CRO companies in China. Status and trend faced to drug manufactory in China. Influence and challenge

caused by financial crisis and method to solve the problems. Session 11 Business Forum: Status and trend of the Bioindustry in the world, bioindustry related stratagy, policy; the operational ways and means in the investment, financing, market entrance promise of bio-product and protecting of property right; the trade and exchange in bioindustry. Attention to Traditional Chinese Medicine Development

BioEco 2009 Chinese medicine forum packed venues, in 11 venues in here can be regarded as a most popular. On 26 and 27 days, there are 20 reports presented by scholars and experts from China, Britain, India, Japan, and Pakistan. There is a problem in almost all repeatedly referred to – “quality assurance system of Chinese medicine”. How to be guaranteed the quality of Chinese medicine? How do to create a standard? For the direction of research, methods Experts put forward their own point of view, the Chinese hope to analyze the material basis and the core of the establishment of Chinese medicine as a quality assurance system.

Experts said that the majority of the active ingredients of traditional Chinese medicine, effective ingredients and toxic effects of substances, toxic effects of substances is not yet clear, the majority of Chinese medicine there is no clear molecular targets, some mechanism is not clear, it is basically in a number of disease models verify some of its therapeutic activity, which is the key to limit the Modernization of Traditional Chinese Medicine bottlenecks.

Professor Chang-Xiao Liu, a number of academicians of Chinese Academy of Engineering, Chairperson of the Forum on Traditional Chinese Medicine Development and experts from the traditional Chinese medicine into a modern, experience becomes the standard. All said that these will be crucial breakthrough in the development of Chinese medicine.

Modernization Research and development of traditional medicine products

Professor Hylands has spent a number of years

investigating the use of emerging technologies to the

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

165

authentication and the eventural standardization of plant extracts. The talk will illustrate the use of high field hydrogen-1 NMR spectroscopic and proteomics methods to investigate these issues as well as their application to “conventional” drug discovery and potentially pharmacokinetics and clinical investigations of the actions of palnt extracts.[1]

Professor Luo and his researchers propose a novel “-omics” approach, chemomics, in which the phytochemical composition of a herbal formula with demonstrated clinical efficacy is regarded as a global chemome, which can be simplified successively through bioactivity –guided screening to achieve an optimized chemome with minimal phytochemical composition for further drug development, while maintaining its curative effect for a specified indication. By integrating chemomics with systems biology, they generated a “system—system” approach, Integrating Systems Biology, which may have a great potential for rapid development of modernized new composite medicine.[2]

The use of traditional alterative and complementary medicines (TACM) including herbal medicines and nutritional supplements has skyrocketed in the last decade as a result of several drawbacks in the use of conventional medicines. Development of TACM so much so their regulations and promotional aspects vary country to country and this makes it difficult to maintain uniform standards. These is an urgent need for the development of international co-ordination for promotion and development of TACM including their assessment, perspectives and potential harmonization of regulation, quality control and clinical uses.[3]

The traditional use of TCM provides solid base for us to study the pharmacological effects of them. The research and development of Danshensu, hydroxysafflor yellow A and escin, which arenatural products from TCM.[4]

Genus Panax consists of more than 10 species that are distributed mainly over the Sino-Japanese floristic region. The underground parts are available medicinal resource in traditional Chinese medicine as well as in folk medicine. In the course of the systematic quality evaluation of Ginseng drugs, three approaches were conducted aiming to elucidate genetic and chemical diversity of them: (1) phytogenetic analysis and dertemination of marker sequences for identification; (2) comparative study on triterpene saponins; and (3) development of a DNA microarray for authentication of Ginseng drugs.[5]

Due the multi-coponent feature of TCM, its quality control is especially important to assure the efficacy of the herbal combinations. The quality control approaches were surveyed and modern techniques including multicomponent quantitation plus fingerprint analysis for several Chinese

herbal medicines. Several commonly used traditional Chinese medicines including roots of Salvia miltirrhiza, the roots of Panax notoginseng, Ganoderma lucidun etc. hve been investigatedby means of phytochemical analysis. In order to obtain more information about the active constituents of TCM in biological system, the in vivo process of several commonly used TCMs was also investigated by HPLC-MS and HPLC-UV methods. Systems biology approach is now being actively practiced for the action mechanism studies of TCMs and their active principles, which provided a valuable approach for complex systems. Currently, genomics, protenomics, metabonomics have obtained good application in TCM studies. Finally, the future aspects with respect to TCM modernization were also outlined.[6]

Resource development of medicinal plants A DNA batcode is a small DNA fragment from an

organism genome which has gained much attention for its potemtial to identifiy plant species. Chen et al tested seven candidate DNA barcodes in the chloroplast and nuclear genomes from a wide range of plant species with a long history of use in traditional herbal medicines. The aim was to identify a universal DNA barcode for species identification. Based on several factors including PCR amplification efficiecy, differential intra- and inter-specific divergances, DNA barcoding gap, and ration of mono- phyletic species recovery, the internal transcribed spacer 2 (ITS2) region of nuclear ribosomal barcode due to its lower efficiency of PCR amplification. Through analysis of more than 5500 plant samples, ITS2 locus shows rates of successful identification at >90% at species level. The trnH-psbA spacer region that was previously proposed as a potential barcode for discriminating plant species shows only >only 70% success rate at species level. Their studies suggest that ITS2 locus is a favorable universal barcode for authenticating species used in traditional herbs across all major plant taxa, while the trnH-psbA spacer may be used as a complementary barcode.[7]

Professor Huang et al investigated the domestication history of Scutellaria baicalensis. A total of 602 samples from 28 wild populations and 451 samples from cultivated population of Scutellaria baicalensis and 22 samples from 1 outgroup Scutellaria rehderiana pupolation were collected.A phylogeographical approach using chloroplast sequences (atpB-rbcL, trnL-trnF and psbA-trnH intergenic spacer) was implemented and 34 hapotypes were identified when three chloroplast sequences were combined. The sequences confirm that populations of Scutellaria baicalensis are the likely progenitors of cultivated Scutellaria baicalensis, and they neither share a common

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

166

ancestor nor are experiencing ongoing gene flow with sympatric Scutellaria rehderiana. This study provides phylogeographic evidence of the Chinese cultivated medicinal plants domesticated from multiple geographic regions. The findings of this study will be useful for understanding the evolutionary process in incipient stages of domestication and provide information for managing and improving the germplasm of cultivated Scutellaria baicalensis.[8]

Professor Xiao analyzed the limitation of quakity control pattern for Chinese medicine, the difference and similarities in the chemical substantial style as well as quality control patterns among Chinese medicine, chemical synthetic drugs and biological products, combining with the autheors experience on the research of geo-authenticated medicinal materials and theory of Chinese medicine nature, a new pattern of quality control for Chinese medicine has been explored and designed.[9]

Ginseng, as the king of the traditional Chinese medicine, has been one of the dominant herbalk resources historically in China. Professor Zhao recognized that the advantage of ginseng resource into the economical and industrial superiority, they have to make every effort to improve the technologies of the processing of ginseng, such as the structural modification of ginsengnosides, the purification and characterization of ginseng proteins, and the development of on-line monitoring technology for the ginseng deep processing.[10]

To evaluate comprehensively the quality of herbal medicines is a challenge because of their diversity of chemical ingredients. Professor Wang proposed a method, quantitative analysis of multi-components by single maker)QAMS), in herbal medicines. Now QAMS has been applied to 16 kinds of herbal medicines such as Panax ginseng and Coptis chinensis. Components such as saponins, alkaloids, flavones, anthraquinones and phenol acids had been applied to establish the relative correction factors(RCF).[11] Professor Du reported the research results on the quality control system for traditional Chinese medicines, and used an experiment result of quality control of Rheum palmatum L. to evaluate the system establishment.[12]

Quality control and evaluation for Traditional medicines

Traditional Chinese medicine (TCM) have played

important role on Chinese people health for a long time. TCM has been constantly in the course of standardization and normalization. However, currently there still have been some problems in the quality control for TCM production. This makes over-all quality control and evaluation difficult.

These situations, which have long time hampered the development of TCM could be changed. The Further development of quality control for TCM should be based on extensive and scientific studies, such as drug material basis, pharmacology, pharmacokinetics, novel pharmaceutics and clinical evaluation on the effect and safety. Advocate interdisciplinary research, consult achievements from other scopes and establish a scientific, reasonable, practical economic, environmental quality standard for TCM. Make sure the TCM are safe, effective, stable and controllable.[13]

Colla corii asiini (E-jiao) is one kinds of most valuable traditional Chinese medicine (TCM) that has a long history of over 2000 years. The modern science and technology used for the standards research would be helpful not only for quality control but also for its authentication of the product. Through the pharmacological research, consumers would know more about the product in a much modernized way. The modernization research carried out on the product will help promote the development of traditional Chinese medicines.[14]. Based on the achievement of Yunnan Baiyao science research, Yuannan Baiyao Group Co. successively create products such as Yunnan Baiyao woundplast, aerosol, plaster, toothpaste and so on, which enjoy the pervasive popularity in the market. The Group Co. applied continually advance technology for the studies on pharmacological actions to raise the quality of TCM products.[15]

Internationalization Research and development of traditional medicine products

Xuezhikang had many national and regional patents in America, Korea, Singapore, Hong Kong and EUPCT, More than 700 articles about the product have been published in China and 30 in international journals. Now, the product is carrying out randomized, double-blind and multi-center phase II clinical trail by FDA licensed. A clinical research of second prevention effect of Xuezhikang on coronary heart disease by modifying lipid, designed as multi-center, randomized, double-blind, and placebo controlled. In total 4870 patients with myocardial infraction were enrolled for an average of 4 years. In the study, the incidence of primary end-points were 5.72% in Xuzhikang treatment group and 10.41% in conterl group, with a reduction of relative risk by 45.1% for Xuezhikang group; the incidenbces of nonfatal myocardial infraction and deaths from coeonary heart disease reduced by 60.8% and 31.0%; the total mortality reduced by 33.0%. The American Journal of Cardiology and Journal of the American Geriatries Society published the full-texts of the design and overall results and old-age subgroups respectively.[16]

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

167

Professor Liu et al evaluated the quality, efficacy, safety of Weinaokang, a novel Chinese herbal medicine for the treatment of vascular dementia.[17] Pharmacological studies have demonstrated statistically significant improvement in learning and memory function in dementia models. The herbal medicine reversed biochemistry and behaviour changes in rat models caused by bilateral common carotid artery ligation, and local cerebral ischrmia induced by obstruction of the right middle cerebral artery to inferior cerebral arteries. Pretreatment with crocin, a pharmacologically active component of the formula, markedly inhibited oxidizing reactions and modulated the ultrastructure of ortical microvascular endothelial cells in stoke mice. In the clinical trail, 62 vascular dementia patients, who 32 received Weinaokang and 30 received placebos. The result exhibited Weinaokang is not effective, but also safe, and constitutes a potential therapeutic candidate in vascular dementia treatment.

(Edited by Liu CX) References 1. Hyland Peter J. Recent innovative chemometric,

metabolomic and cheminformatic studies on traditional Chinese medicines. 2009 BioEco Abstracts 107-108.

2. Luo Guo-An. Liang Qiong-Lin, Wang Yi-Ming. Development of systems biology and its application in the R&D of new drugs from TCM. 2009 BioEco Abstracts 126-129.

3. Mukherjee PK, Venkatesh M. Strategies for revitalization of traditional alternative and complementary medicine with international cooperation. 2009 BioEco Abstracts 108-109.

4. Fu FH. Research and development of natural drugs based on traditional Chinese medicine: Opportunity and challenge. 2009 BioEco Abstracts 137-138.

5. Momatsu K and Zhu S. Genetic and chemical diversity of Ginseng drugs and the development of DNA microarray for authentication. 2009 BioEco Abstracts 110-111.

6. Guo DA, Liu X, Ye M, Guan SH, Yang M. Modernization of traditional Chinese medicine: Current status and future perspectives/ 2009 BioEco Abstracts 117-119.

7. Chen SL, Yao H, Han JP, Shi LC, Zhu YJ. Identification of medicinal plants DNA barcode technology. 2009 BioEco Abstracts 122-124.

8. Huang LQ. Domestication of a cultivated Chinese medicinal plant, Scutellaria baicalensis. 2009 BioEco Abstracts 113-115.

9. Xiao XH, Jin C, Yan D, Wang JB. Quality controland valuation for Chinese medicines by bioassay. 2009 BioEco Abstracts 129-134.

10. Zhao DQ. Key scientific issues on Ginseng processing and conversion. 2009 BioEco Abstracts 142-143.

11. Wang ZM.Study on the pattern enclosing the effective chemical substances and quality control of herb medicines. 2009 BioEco Abstracts 126-128.

12. Du PF. Establishment on quality control system of traditional Chinese medicines. 2009 BioEco Abstracts 135.

13. Lin RC. Thinking on the quality stabdards for traditional Chinese medicine. 2009 BioEco Abstracts 115-117.

14. You JH. Modernization research on the traditional Chinese medicine Colla croii asini. 2009 BioEco Abstracts 136-137.

15. Wang Z. The scientific and technological innovation of Yunnan Baiyao. 2009 BioEco Abstracts 143-144.

16. Guo SR. Evidence-based medicine and internationalization of Xuezhikang capsule. 2009 BioEco Abstracts 139-140.

17. Liu JX，Chang D, Wang JN, Cong WH, Li XZ, Zhang Y, Chan D， Bensoussan A. Development of a Chinese herbal medicine，Weinaokang，the Sino-Australian Collaboration. 2009 BioEco Abstracts 120-122.

Special Report. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：163-168

168

Special Report Strategies for revitalization of traditional alternative and complementary medicine with international cooperation

Professor Pulok K. Mukherjee visited Tianjin Institute of Pharmaceutical Research, China, on June 29, 2009. During the visitation, Professor Mukherjee made an academic lecture titled “Strategies for revitalization of traditional alternative and complementary medicine with international cooperation” to scientists from Tianjin Institute of Pharmaceutical Research, Tianjin University and Tianjin University of Traditional Chinese Medicine

Dr Pulok K. Mukherjee is working as Director, School of Natural Product Studies, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India. Dr. Mukherjee is Associated Editor of Journal of Ethnopharmacology and a member of Editorial Committee of Chinese Herbal Medicines. He completed M. Pharm and PhD from Jadavpur University and completed his post doctoral research from Leiden, Amsterdam Center for Drug Research, The Netherlands. He has been admitted as Fellow of the Royal Society of Chemistry，UK。 His research interest is in the field of natural health products based on screening, safety evaluation, formulation and standardization of herbal drugs and allied approaches. He has to his credit more than 100 publications in peer reviewed journals, several patents and books on evaluation of botanicals. Strategies for revitalization of traditional alternative and complementary medicine with international cooperation

Medicinal plants are important for pharmacological research and drug development to treat various ailments due to the synergistic effects of several plant constituents in herbal medicinal products or when the plant constituents are used directly as therapeutic agents. Globally, there has been an unparalleled growth in the medicinally useful formulations, drugs and health care products derived from plant origin. The use of traditional alterative and complementary medicines (TACM) including herbal

medicines and nutritional supplements has skyrocketed in the last decade as a result of several drawbacks in the use of conventional medicines. Renewed interest in usage of TACM globally has opened new areas for exploration and debate. During the past decades, public interest in natural therapies, namely herbal medicine, has increased dramatically not only in developing countries but mainly in industrialized countries. TACM including Ayurvede from India and traditional Chinese medicine of China are part of the health care globally. The different cultures in different countries influence the use of the herbal medicines, thus the definition and the categorization is difficult along with that the regulation for them also differs. While several phyto-medicinal agents have been used for a long time and thoroughly evaluated for safety and efficacy, the majority of TACM yet remain unevaluated.

Despite the use of TACM over many centuries, only a relatively small number of plant species has been studied for possible medical applications. Safety and efficacy data are available for an even smaller number of plants, their extracts and active ingredients and preparations containing them. Safety and efficacy of these TACM are always a cause of concern to promote and rationalize their use. Quality control of TACM, validated processes of manufacturing, costumer awareness and post marketing surveillance are the key points which could ensure their safety and efficacy. Identification and quality evaluation of crude drugs is a fundamental requirement of industry and other organizations dealing with botanicals. Marker analysis based on chemical profiling and development of characteristic fingerprints for individual plants could help to develop uniform standardization tool.

Implementation of GMP guidelines and product information to consumers, through awareness program could be helpful in monitoring the manufacturing and use of TACM. Development of TACM so much so their regulations and promotional aspects vary country to country and this makes it difficult to maintain uniform standards. These is an urgent need for the development of international co-ordination for promotion and development of TACM including their assessment, perspectives and potential harmonization of regulation, quality control and clinical uses.

(Edited by Liu CX)

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

169

Asian Journal of

Pharmacodynamics and Pharmacokinetics

ISSN 1608-2281 Copyright by Hong Kong Medical Publisher

Publisher Homepage: www.hktmc.com

Recent research trends in intranasal therapeutics – Select case studies of various therapeutic strategies with pharmacokinetic/pharmacodynamic attributes and drug development considerations Nuggehally R Srinivas* Integrated Drug Development Suramus Biopharm 77, 10th Cross, 29th Main, J.P. Nagar I Phase, Bangalore 560 078, India

Abstract There is a growing impetus for exploring intranasal therapeutics as an alternate choice to the conventional oral route of dosing especially for compounds that have issues with oral bioavailability due to factors related to first pass metabolism and/or hindrance from efflux transporter mechanisms. Intranasal route offers an important avenue for rapid attainment of peak systemic concentrations because it provides an efficient environment for drug absorption owing to its vasculature and absorptive surface. It also claimed that intranasal route may be more preferred for rapid brain targeting of drugs. Nevertheless the compound should manifest certain key requirements such as high potency, high solubility, good permeability, amenable to formulation strategies for efficient intranasal delivery. Additionally, the activity should reside entirely in the parent compound because metabolite(s) formation, unlike oral administration, is not expected to happen to the same extent through the nasal mucosa. The current research trend suggests that intranasal therapeutics is being developed in multiple therapeutic areas to combat conditions of diabetes, Alzhemer’s disease, anxiety disorders, emesis, acute pain etc. This review focuses on the latest nuances in this intriguing field of intranasal therapeutics that are being explored with a focus on pharmacokinetic and pharmacodynamic aspects, wherever applicable. It also provides a brief update on the technology and formulation strategies for a successful attempt to deliver the drug through the intranasal cavity. Additionally, brief perspectives regarding drug development considerations are provided. In summary, it appears that line extension option of marketed oral, subcutaneous or intravenous product(s) to an intranasal delivery product, if feasible, appears to be a prudent strategy.

Key words Bioavailability; Delivery Drug Development; Formulation; Intranasal; in vitro and in vivo performance; Pharmacodynamics; Pharmacokinetics; Therapeutics; Therapeutic strategies

Article history Received 20 August 2008; Accepted 25 May 2009 Publication data Pages: 10; Tables: 0; Figures: 0; References: 28; Paper ID 1608-2281-2009-09030169-10 *Corresponding author Dr. Nuggehally R Srinivas, Integrated Drug Development, Suramus Biopharm, 77, 10th Cross,

29th Main, J.P. Nagar I Phase, Bangalore 560 078, India, Email: srini.suramus@yahoo.com

Introduction

Recent trend clears show that intranasal therapeutics is steadily gaining momentum since it

provides an opportunity to deliver drugs both for local application and for systemic applications. The present day advances in formulation technology and choices of novel polymers have immensely

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

170

contributed for effectively delivering a number of drugs via intranasal cavity. In an elaborate review, Constantino et al (2007)[1] described the various intranasal delivery options intended to treat several diseases – the review also provided the physicochemical attributes of several drugs being considered for intranasal dosing.[1] On the other hand, the review of Vyas et al (2006)[2] featured the challenges involved in the delivery of agents used for central nervous system disorders through intranasal route. Additionally, the role of physicochemical parameters, formulation rationale and optimization steps were discussed to enable a rapid nose to brain transport of important drugs.[2] The success of intranasal route in effectively delivering agents has been documented in many important therapeutic indications such as headache (migraine) pain[3] and allergic rhinitis.[4]

The scope of this review entails the following: a) to provide perspectives on the use of intranasal route; b) to provide an update on the recent trends in technology advancement and/or formulation strategies for intranasal delivery; c) to summarize the recent developments in the field of nasal therapeutics by providing relevant case studies – focus on pharmacokinetic and pharmacodynamic attributes that were essential for the selection of intranasal delivery option; and d) to provide some drug development considerations Considerations for intranasal route—Advantages and challenges

Interestingly, intranasal route offers some clear distinct advantages as a possible alternative route for the most popular and well studied oral route of administration of large number of therapeutics. Some of the unique features include: 1) patient factors: convenience, easy administration, maintenance of patients’ privacy; 2) biopharmaceutic considerations: satisfactory surface area, easy access for permeation through porous epithelial surface; 3) physiological attributes: above average blood flow, complete escape from first-pass metabolism mediated via gastrointestinal tract and liver, 4) formulation attributes (to overcome the tight junction) and 5) pharmacokinetic attributes: lesser opportunity for drug-drug interaction potential, rapid delivery for brain targeting, rapid attainment of peak levels for certain category of drugs. However, intranasal route offers certain challenges that need to be factored during the evaluation of using intranasal therapeutics. These challenges include: 1) unlike oral route where

a larger dose size is feasible, the intranasal delivery can accommodate a ‘finite’ size of the dose to be administered; 2) the potency of the compound – it is highly desirable that the compound manifests high potency to minimize the intranasal dose size; and 3) due to short time of residence in the intranasal cavity, the compound should have high aqueous solubility for ready absorption and resist the ciliary’s motion occurring in a posterior direction that would tend to push the drug solution outside. Techology advancement for intranasal intranasal delivery/formulation options-update

The present day advancement in technology has rendered the delivery of small molecules, peptides, proteins and anti-sense compounds feasible via the intranasal cavity.[5] The experience gained by the application of mucoadhesive systems for oral drug products has been aptly applied in the development of bioadhesive systems to target range of compounds through intranasal mucosa. The formulation approaches in this important category comprises of: gel based systems, liposomal based systems and microspheres based systems. Although such technologies seem to provide a base for delivery of bigger macromolecules, it does not seem to be far-fetched to apply the same ideas in the design of such compatible systems for smaller drug molecules.[5] It appeared that the proper selection of excipients and/or type of polymer within the three types of systems was the key to control the residence time in the nasal cavity, protection from possible enzymatic degradation and as well to impart better penetration properties through the nasal mucosal membrane.[5]

In 2005, Johnson and Ouay have reported the latest nuances in our understanding of tight junctions and the pertinent research work that has been in progress to identify unique modulators of the tight junctions by the application of present day high-throughput molecular biology screens.[6] In the well organized review, the authors have placed emphasis in the development of novel peptides and/or other molecules that has the potential to reversibly open the difficult to crack tight junction barriers.[6] It is conceivable that opening of tight junction barriers could change the drug absorption dynamics from the intranasal cavity and the use of such a technology has

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

171

been explored in the development of a novel intranasal formulation for an anti-obesity drug.[6] Recently, Song et al have proposed a synthetic peptide, AT1002, which has the ability to open the tight junctions in a reversible fashion and therefore, may find use in the paracellular transport of drugs.[7] Using, insulin as a model substrate and in rat model, it was demonstrated that total exposure of insulin was increased by 3-fold by the pre-treatment with AT1002.[7] This study suggested the utility of AT1002 to improve the systemic bioavailability of several macromolecules administered via intranasal route.[7] In 2007, the research work performed by McInnes and co-workers showed the need to achieve optimization to keep a balance between adhesion and over hydration with lyophilized insulin insert formulations containing 1 to 3% hydroxypropylmethylcellulose (HPMC).[8] It was observed that 2% HPMC content achieved extended nasal retention of insulin, whereas 1% HPMC contributed to a faster clearance from nasal cavity and 3% HPMC did not show spreading properties and was cleared intact in about 90 minutes.[8]

Mainardes et al have extensively reviewed the intricacies and development problems with regard to well understood options of liposomal and micro/nanoparticle based systems to act as possible colloidal carriers for efficient nasal drug delivery strategies.[9] Other recent developments include the introduction of akylsaccharide transmucosal delivery enhancing agents – they appeared to have applicability for a wide range of diseases.[10] These interesting newly introduced absorption enhancers are called as Intravail and they are purported to provide enhanced bioavailability without causing nasal irritation, another common problem encountered with intranasal formulation containing absorption enhancers.[10] About the same time, another interesting review which focussed on the applicability of various absorption enhancers and complete exploitation of the bioadhesive system was published.[11] Amongst other things, the use of chitosan as an absorption enhancing agent for a large number of compounds for intranasal delivery was described.[11] Case studies: Applicability of intranasal therapeutic options in combating numerous diseases

Option for the treatment of Type 1 diabetes A newly developed intranasal formulation was

tested in type 1 diabetic patients (n = 7) using subcutaneous insulin and/or placebo as comparators. While it was confirmed that intranasal formulation was well tolerated and effective, the relative bioavailability of insulin from the intranasal route was between 15-20% of the subcutaneous route of administration. However, it was important to note that peak insulin levels was attained within 15-20 minutes after dosing and the distribution phase appeared to last for more than 1 h. Interestingly, the pharmacodynmic profile (i.e., reduction in serum glucose levels) seemed to mimic the pharmacokinetic profile with a lag of about 20 minutes in its peak pharmacodynamic effect which waned off approximately 1.5 to 2 h post dosing. On the basis of the relative bioavailability, it appeared that higher intranasal doses may be needed to achieve pharmacodynamic equivalence obtained from a subcutaneous dose. [12]

Option for the treatment of migraine

headache Since migraine attacks typically manifest with

severe gastrointestinal disturbances, it may be difficult to swallow oral tablets to combat migraine headache pains. Therefore, intransal anti-migraine medications such as rizatriptan and zolmitriptan may provide a better therapeutic alternative as compared to oral treatment options.

Rizatriptan:[13] A novel nasal spray of rizatriptan was developed which was designed for a faster absorption through the nasal cavity. The intranasal pharmacokinetics of rizatriptan appeared to be closely matching with those of oral pharmacokinetic profile in terms of total drug exposure (relative bioavailability for the intranasal delivery was established to be approximately 96%). However, the peak levels appeared to be higher and attainment was much rapid suggesting that intranasal option of rizatriptan may provide the much needed faster relief from the migraine episodes.

Zolmitriptan:[14] Another important anti-migraine agent, zolmitriptan, has been formulated for dosing via intranasal route – the route demonstrated high tolerability, rapid onset of activity and good efficacy.

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

172

In an interesting study, the pharmacokinetics of zolmitriptan and its active metabolite (183C91) were compared between intranasal and intravenous routes of administration. Although the plasma appearance of the active metabolite was delayed by almost 30 minutes following intranasal dosing as compared to oral route, the parent zolmitriptan achieved initially much higher levels as compared to oral administration (i.e, circulatory levels of zolmitriptan was observed within 2 minutes after intranasal dosing). Therefore, it confirmed the effectiveness of zolmitriptan and its other predecessors in relieving migraine attacks following intranasal dosing.

Option for the treatment of psychotic

episodes In an interesting study the pharmacokinetic

profiles of haloperidol were compared following intravenous, intramuscular and intranasal routes of administration in healthy subjects (n=4). With the exception of some minor nasal irritation following intranasal administration, the tolerability profiles appeared to be comparable amongst the three routes of administration. The intranasal route favoured better than intramuscular route in terms of relative bioavailability of haloperidol (64% versus 49, both relative to intravenous administration). It was important to note the median time to achieve peak levels after intranasal administration coincided with that of intravenous route (i.e., 15 minutes) but was twice faster than that of intramuscular route (i.e., 38 minutes). [15]Therefore, the data suggested that intranasal route of haloperidol may provide a potential alternative to intravenous route in treating psychiatric emergencies and/or in patients who may pose danger for inserting intravenous lines for drug administration. Both from pharmacokinetic and expected pharmacodynamic attributes, intranasal route for haloperidol and/or other antipyschotics may have distinct advantages.

Option for the treatment of anxiety disorders An early formulation development work has

suggested the possibility of development of a good intranasal system for the effective delivery of buspirone. In the preliminary work it was found that incorporation of chitosan hydrochloride excipient in the hydroxypropyl-β-cyclodextrin polymer improved

the permeability characteristics of buspirone as compared to the control buspirone hydrochloride solution. The optimization experiments revealed that permeability increase could be up to 3.5 fold and nasal clearance studies with radioactive ligands revealed that there was also an increased retention of buspirone when formulated with chitosan and HP-β-cyclodextrin system. Since buspirone undergoes extensive presystemic metabolism, the intranasal delivery option via improved systems such as the one described above should improve the bioavailability. However, the caveat in cases of drugs undergoing presystemic metabolism, the contribution if any from the active metabolite(s) towards the pharmaco- dynamic profiles may be difficult to be matched by intransal routes owing to the possible route dependent differences in disposition and metabolic profiles. [16]

Option for the treatment of Alzheimer’s

diseas The potential role of intranasal delivery route for

brain targeting of drugs such as a tacrine was investigated via gamma scintigraphy imaging study in rabbits. In this investigation, two formulations of tacrine were considered (micro emulsion/muco adhesive formulation versus solution formulation) to compare and contrast the brain penetration kinetics and bioavailability. The formulated tacrine appeared to have 2-fold higher bioavailability than solution formulation. The gamma scintigraphy imaging data suggested that direct nose to brain drug transport was achieved (60 minutes) much faster than that following intravenous tacrine administration (120 minutes). Also, the brain uptake of tacrine from intranasal route was far greater following intranasal as compared to intravenous administration. Overall, these early data provide evidence that delivery of tacrine using intranasal route may have a meaningful role to play in the management of Alzheimer’s disease.[17]

Option for the treatment of emesis In order to effectively treat conditions of emesis

non-oral route may be a preferred choice for obvious reasons. In this context, an interesting intranasal delivery option for metoclopropamide hydrochloride was investigated in comparison to a neat drug solution.[18] The intranasal formulation, which was a

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

173

well optimized mucoadhesive gel containing polyethylene glucol polymer, was devised to increase the residence time in nasal cavity for an improved bioavailability without compromising the in vitro release kinetics for the complete release of metoclopropamide withn 1 hour. In vivo study in rats suggested that the formulated metoclopropamide prolonged the residence time in nasal cavity from approximately 10 (ordinary solution) to 52 minutes; whereas the absolute bioavailability study in a higher species such as rabbits revealed a marked improvement from the formulated drug (about 70%) as compared to the solution (about 50%).

Option for contraceptive needs Although oral contraception routes are popular,

an investigation was carried out on an important contraceptive agent, levonorgestrel, in a rat model – it was suggested that intranasal option may be needed for effective and speedy delivery of levonorgestrel to the systemic circulation. In this pharmacokinetic and pharmacodynamic study in rats, two different intranasal formulations (sterylglucoside based and chitosan based) were compared with a oral suspension formulation of levonorgestrel.[19] It appeared that the sterylglucoside based intranasal formulation achieved faster and higher peak concentrations (1 h and 417 ng·ml-1) as compared to both chitosan-based intranasal formulation (2 h and 228 ng·ml-1) and oral suspension (1.9 h and 335 ng·ml-1). Interestingly, the relative bioavailability of the two intranasal delivery options were 100% as compared to oral suspension and provided a differentiation in the delivery option of levonorgestrel – sterylglucoside based intranasal formulation would provide a much rapid delivery of leonorgestrel and chitosan based formulation due to its longer retention in the nasal cavity tends to provide a sustained delivery of the drug.

Option for the treatment of drug addictions An interesting pharmacodynamic investigation

was carried out to check the utility of an intranasal administration of diamorphine as a potential therapeutic option instead of the intravenous diamorphine for maintenance treatment in patients being treated for severe drug addictions. Although from a pharmacokinetic perspective, the intravenous

route appeared to initially deliver faster and higher magnitude of both morphine and its metabolite concentrations, it evened out with time. The pharmacodynamic scores (withdrawal rating scores) were comparable between the two routes of administration and patients provided a favourable opinion on the intranasal spray owing to its ease of administration, lesser stigma and total avoidance of needle related problems. [20] Therefore, there was a suggestion for consideration of intranasal diamorphine treatment option as a potential alternative to the current intravenous option.

Option to reduce the side effect profile of an

important agent A cleverly designed in vitro study (tissue model

of human nasal epithelium) along with a formulation screening study in rats administered with intranasal galantamine was combined to evaluate the possible utility of intranasal therapeutic option. Since the oral galantamine use to treat Alzheimer’s disease is associated with severe emetic response owing to its acetylcholinesterase inhibition, an intransal was explored to circumvent and/or minimize both emesis and retching. The in vitro study established superior permeation of the drug through the nasal epithelium membrane without cytotoxicity (or damage) to the membrane; whereas the in vivo pharmacokinetic study documented higher bioavailability and lowered side effect profiles as compared to the corresponding oral dosing of galantamine.[21]

Option to promote an anti-inflammatory

agent for acute pain treatment Ketolorac is available as parenteral formulation

for treatment of moderate to severe acute pain via intravenous and/or intramuscular routes of administration. It appeared that physicochemical properties of ketolorac such as high solubility, amenability of salt formation couple with excellent potency would render it an excellent candidate for intranasal dosing route.[22] In a well planned clinical investigation the comparative pharmacokinetics of ketolorac between intranasal versus intramuscular routes of administration were evaluated in 15 healthy subjects at two dose levels. The rapid attainment of peak concentrations of ketolorac was possible after intranasal dosing such that the time to peak level was

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

174

found to be 15 minutes lower than observed from the intramuscular dosing (30 min and 45 min, for intranasal and intramuscular routes, respectively). Although the relative bioavailability was somewhat lower after intranasal dosing (ranged between 67 to 75% at the two dose levels examined) the authors felt that the plasma concentrations were within the optimal ranges to display the desired pharmacodynamic outcomes expected of the agent.

Option to promote sedation and pro-

anaesthetic medication treatment Intravenous midazolam, a short acting compound,

is used for its sedative properties to promote and enhance anaesthesia prior to surgical procedures.[23] In this study, two different intranasal delivery devices of midazolam, namely, regular/traditional nasal spray and bidirectional nasal spray, were evaluated, using both pharmacokinetics (bioavailability) and pharmacodynamic (sedation scores) measurements. The two devices appeared to deliver midazolam similarly leading to bioequivalence in their exposures to the parent drug. While bidirectional nasal spray device did not increase the systemic bioavailability of midazolam, it appeared to produce sedation which closely matched that observed after intravenous midazolam treatment. The sedation properties of the traditional nasal spray appeared to be less pronounced suggesting that bidirectional spray may produce qualitative differences in the initial distribution phase for an improved pharmacodynamic outcome.

Interestingly, another group of researchers compared intranasal administration of midazolam (via liquid instillation) with that of a nebulised formulation of midazolam delivered by a standard nebulizer.[24] The pharmacodynamic measures were detailed and included sedation scores, visual analogue scores and critical flicker fusion frequency assessment, whereas the pharmacokinetic measures simply measured the plasma levels of midazolam. It was evident that intranasal route was far superior to that of the nebulised treatment – all three pharmacodynamic markers supported this conclusion. Interestingly, the exposure to midazolam after intranasal dosing far exceeded (approximately 3-fold greater) with that observed for the nebuliser option. The study suggested that intranasal route of

delivering midazolam could potentially be important one in the management of sedation and pro-anaesthetic treatments in patients undergoing surgery.[24] Drug development considerations

Although significant progress has been achieved in the understanding of the dynamics of intranasal absorption of drugs and technological advancement in delivery systems, development of drugs using this route is very challenging and key considerations are as follows.

Mechanistic aspects of intranasal versus oral

absorption Recently, Furubavashi et al [25] have conducted

an elegant study in a rat model, in understanding the mechanistic aspects of nasal absorption versus gastrointestinal absorption including the dynamics of permeability coefficients for its contribution towards drug absorption. Per the extensive evaluation, authors confirmed that for drugs that have a very high permeability coefficient, intranasal mucosa is the primary region for absorption. In converse, the absorption was found to be relegated to gastrointestinal region if the drug(s) displayed mediocre to poor permeability coefficient constants.[25] Therefore, they suggested that for highly permeable drugs, intranasal route of administration would shift the absorption curve to the right side – supporting the theory that intranasal route can produce rapid and significant exposures for drugs that satisfy the key physicochemical requirements.[25]

Pharmacological activity It is important that the pharmacologic and

pharmacodynamic attributes of the drug should be solely contributed by the parent compound. Especially if oral products are being explored for possible intranasal switching option, it is imperative that the disposition of the parent compound does not produce active metabolite(s), via presystemic metabolism, that also would contribute for the elicited pharmacological activity. Because the formation of active metabolite(s) through the passage of drug through the nasal epithelial mucosa is unlikely and therefore, there will be disparity in the

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

175

parent: metabolite profiles between the oral administration versus the intranasal dosing – this in turn, may contribute for therapy failure. However, if the active metabolite(s) are equipotent and formed in minor amounts after oral administration, it should not represent a big issue for intranasal product development because intranasal route may compensate by somewhat higher bioavailability of the parent compound in lieu of reduced formation of the active metabolite(s).

Prodrug strategy Unilke oral route, where increasingly prodrug

strategy has been used to overcome certain barriers of absorption and/or to promote effective delivery to the systemic circulation without significant degradation of the product, intranasal route is not amenable for that strategy. Therefore, it will be difficult to make product switches of marketed oral prodrugs to the intranasal route. In such instances, the feasibility of the active moiety (from the hydrolysis/cleavage of the prodrug) by itself for intranasal absorption and effective intranasal delivery needs to be explored.

Preclinical Unlike oral or intravenous routes of

administration, it is extremely challenging to administer intranasal doses to toxicology species: notably, mouse and rats especially if the supportive data are needed to support clinical trials for intermittent human use of the intranasal product. Although drug solutions are instilled carefully in the nostrils of the rodents, still it is very cumbersome process which would require expertise in small volume dosing techniques. There may be opportunity for drug loss due to the difficulty in instilling because there may be need to instil the drug more frequently to achieve the required high doses (and/or exposure) needed to support the program. However, there may be an opportunity to use intravenous route to supplement the toxicology data provided the intranasal epithelium does not metabolize the compound(s) during the absorption through the intranasal mucosa. Therefore, if the drug is rapidly absorbed and the bioavailability is very high (perhaps in the 90% vicinity), one could possibly argue the use of intravenous route to determine the intermittent toxicity of the compound – however, it is imperative

to demonstrate that the nasal epithelium does not produce any metabolites through in vitro experiments. Additionally, there may be also the requirement to evaluate the potential for local irritation (i.e., intranasal mucosa) as a result of drug delivery. Similarly, even the selection of non-rodent species may provide a challenge since intranasal dosing techniques are difficult to follow in higher species of animals- especially handling of monkeys may portray difficulties. There may be limited Clinical Research Organizations that may offer specialized dosing techniques such as intranasal dosing for various preclinical tests including toxicology related work.

Clinical Starting dose determination: While the first

human dose (starting dose) determination is a challenge because of difficulties in the conduct of intranasal studies in rodent species – in spite of the challenges one could arrive at a safe starting dose in humans for intranasal dosing. It is quite possible to use other factors such as pharmacological considerations and/or exposure to guide the selection of the first dose in humans.

Limited dose escalation flexibility: Unlike oral or intravenous where the use a wider range of doses is followed intranasal dose escalation studies are done at a narrower range. This is simply because there is a limitation with regard to the maximum volume that could be possibly delivered to each nostril at any given time. For example, the intranasal dose escalation study for BMS-181885, a 5-HT1 agonist, was carried out within a 4-fold range (escalating doses were: 3, 6 and 12 mg of BMS-181885).[26]

Pharmacokinetic monitoring/ importance of early sample collection: Since the nasal administration of the drug has the potential for a rapid absorption (sometimes it could mimic intravenous dosing), it is important that early blood collections are included in the protocol to ensure adequate characterization of the rapid absorption and distribution phases of the compound. This would also enable to accurately estimate the bioavailability of the parent compound from this route of administration because non-inclusion of early time points in the calculation of area under the curve may lead to significant under prediction of the bioavailability.

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

176

Bioavailability and bioequivalence assessment: As part of drug development program it becomes

necessary to evaluate both relative bioavailability and bioequivalence of drug products especially when major formulation changes are being made to ensure that the rate and extent of absorption of the parent compound (surrogate to efficacy and safety) does not alter between the newly introduced product to that of the one used earlier – this is also an important consideration for intranasal product development. In an interesting research work using intranasal butorphanol as a tool, Wermeling et al (2005)[27] have shown that there could be large differences in the administration of dose of butorphanol with two nasal spray systems (unit dose spray and multiple dose spray) such that it resulted in bioenquivalence of butorphanol in both rate of absorption and extent of absorption parameters. For example, the upper limit of 90% confidence interval for both Cmax and AUC parameters exceeded the upper boundary of 1.25 using the average bioequivalence assessment.[27] It was also found that the target dose (using weighing options) delivered by the unit dose device generally exceeded the target by 3%, whereas the target dose delivered by the multiple dose device generally fell 10% below the target. Therefore, as part of the development strategy it is important to keep a close vigil on the nasal spray device that is used for initial clinical pharmacology studies and one has to plan for bridging pharmacokinetic and tolerability studies if either the nasal devise and/or formulation are changed during the next phases of development.

Assessment of the in vitro and in vivo (IVIVC)

performance: In 2004, Newman et al [28] describe elegantly the

various requirements for intranasal delivery of drug from an IVIVC view point. Accordingly the battery of in vitro assessment to evaluate the performance of the nasal spray should include: dose released, particle size distribution, spray pattern and plume geometry. The in vivo assessment for the performance of the nasal spray may be assessed by two-dimensional imaging technique such as gamma scintigraphy and/or three-dimensional imaging method such as positron emission tomography.[28] This review suggests that in some instances data exists that

represents good predictability of in vitro characteristics of nasal spray devise to in vivo performance; however, in certain cases there was a poor IVIVC.[28] Therefore, it is important that during the initial development some reliable parameters are developed and IVIVC established to further guide the nasal spray product development through in vitro work.

Regulatory Consideration of intranasal route is as a line

extension for oral and/or intravenous route. It is possible to use the safety data gathered in

other routes of administration such as oral and intravenous, to support the strategy for development of intranasal dosing option for the compound in question. If higher doses have been tested by other conventional routes in clinical settings, there is enough safety window firmly established. It would be a great strategy to switch a marketed oral and/or parenteral compound to intranasal route provided there is justification in the selection of such a route. The development of several intranasal options for combating migraine attacks is a classical example for this. In such situations, if the compound fulfils the requirements for intranasal delivery, the onus would be on the sponsor to confirm the safety and efficacy of the new route. Additional supportive data to ensure there is no toxicological issue and/or other safety issues (inclusive of route specific adverse event assessment) as a result of intranasal dosing needs to be gathered by the sponsor as part of the supplemental package for obtaining marketing authorization.

Conclusions

Intranasal route is particularly suited to deliver

rapid absorption for highly potent compounds that would otherwise fulfil other requirements for packaging itself in the intranasal delivery form. Although acute therapy and/or intermittent therapy would be best suited for intranasal delivery options, it needs to be appreciated that not all drugs have the ability to be delivered through the intranasal route. The present day development in technology development and formulation strategies provide unique blend of polymers, absorption enhancers and

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

177

other latest nuances to effectively deliver drug(s) through the intranasal cavity – the field has exponentially exploded as exemplified by the various case studies presented in this review.

The requirements and strategies for the first approval of an intranasal product pose considerable challenges for drug development alongside downside risk of therapy failures. However, a line extension strategy may be considered using the available data from other routes such as oral, intravenous and/or subcutaneous for already marketed drugs, which could be leveraged in putting through a sound clinical and regulatory plan for the approval of the product for intranasal route. Here, reference is made to the successful launches of anti-migraine products for intranasal route which previously had first received market approvals for oral and subcutaneous routes of administration. If the present trend of unabated research continues, it is anticipated that intranasal route would emerge as an important option in emergency situations to combat many disease(s).

References 1. Costantino HR, Illum L, Brandt G, Johnson PH, Quay SC.

Intranasal delivery: physicochemical and therapeutic aspects. Int J Pharm 2007; 337(1-2): 1 – 24.

2. Vyas TK, Tiwari SB, Amiji MM. Formulation and physiological factors influencing CNS delivery upon intranasal administration. Crit Rev Ther Drug Carrier Syst. 2006; 23(4): 319 – 347.

3. Rapoport A, Winner P. Nasal delivery of antimigraine drugs: clinical rationale and evidence base. Headache 2006; 46 (Suppl 4): S192 – S201.

4. Hochhaus G. Pharmacokinetic/pharmacodynamic profile of mometasone furoate nasal spray: Potential effects on clinical safety and efficacy. Clin Ther 2008; 30(1): 1 – 13.

5. Turker S, Onur E, Ozer Y. Nasal route and drug delivery systems. Pharm World Sci 2004; 26(3): 137 – 142.

6. Johnson PH, Ouay SC (2005) Advances in nasal drug delivery through tight junction technology. Exp Opin Drug Deliv 2005; 2(2): 281 – 298.

7. Song KH, Fasano A, Eddington ND. Enhanced nasal absorption of hydrophilic markers after dosing with AT1002, a tight junction modulator. Eur J Pharm Biopharm 2008; 69(1): 231 – 237.

8. McInnes FJ, O’Mahony B, Lindsay B, Band J, Wilson CG, Hodges LA, Stevens HN. Nasal residence of insulin containing lyophilized nasal insert formulations, using gamma scintigraphy. Eur J Pharm Sci 2007; 31(1): 25 – 31.

9. Mainardes RM, Urban MC, Cinto PO, Chaud MV, Evangelista RC, Gremiao MP. Liposomes and micro/nanoparticles as colloidal carriers for nasal drug delivery. Curr Drug Deliv 2006; 3(3): 275 – 285.

10. Maggio ET. Intravail: highly effective intranasal delivery of peptide and protein drugs. Exp Opin Drug Deliv 2006; 3(4): 529 – 539.

11. Illum L. Nasal clearance in health and disease. J Aerosol Med 2006; 19(1): 92 – 99.

12. Leary AC, Stote RM, Cussen K, O’Brien J, Leary WP, Buckley B. Pharmacokinetics and pharmacodynamics of intransal insulin administered to patients with type 1 diabetes: a preliminary study. Diabetes Technol Ther 2006; 8(1): 81 – 88.

13. Chen J, Jiang XG, Jiang WM, Gao XL, Mei N. Intranasal absorption of rizatriptan – in vivo pharmacokinetics and bioavailability study in humans. Pharmazie 2005; 60(1): 39 – 41.

14. Uemura N, Onishi T, Mitaniyama A, Kaneko T, Ninomiya K, Nakamura K, Tateno M. Bioequivalence and rapid absorption of zolmitriptan nasal spray compared with oral tablets in healthy Japanese subjects. Clin Drug Investig 2005; 25(3): 199 – 208.

15. Miller JL, Ashford JW, Archer SM, Rudy AC, Wermeling DP. Comparison of intranasal administration of haloperidol with intravenous and intramuscular administration: a pilot pharmacokinetic study. Pharmacotherapy 2008; 28(7): 875 – 882.

16. Khan SA, Patil KS, Yeole PG. Intranasal mucoadhesive buspirone formulation: in vitro characterization and nasal clearance studies. Pharmazie 2008; 63(5): 348 – 351.

17. Jogani VV, Shah PJ, Mishra P, Mishra AK, Misra AR. Intranasal mucoadhesive microemulsion of tacrine to improve brain targeting. Alzheimer Dis Assoc Disord 2008; 22(2): 116 – 124.

18. Zaki NM, Awad GA, Mortada ND, Abd Elhady SS. Enhanced bioavailability of metoclopropamide HCl by intranasal administration of a mucoadhesive in situ gel with modulated rheological and mucociliary transport properties. Eur J Pharm Sci 2007; 32 (4-5): 296 – 307.

19. Ding WX, Oi XR, Fu O, Piao HS. Pharmacokinetics and pharmacodynamics of sterylglucoside-modified liposomes for levenorgestrel delivery via nasal route. Drug Deliv 2007; 14(2): 101 – 104.

20. Mitchell TB, Lintzeris N, Bond A, Strong J. Feasibility and acceptability of an intranasal diamorphine spray as an alternative to injectable diamorphine for maintenance treatment. Eur Addict Res 2006; 12(2): 91 – 95.

21. Leonard AK, Sileno AP, Brandt GC, Foerder CA, Ouay SC, Constantino HR. In vitro formulation optimization of intranasal galantamine leading to enhanced bioavailability and reduced emetic response. Int J Pharm 2007; 335(1-2): 138 – 146.

22. McAleer SD, Majid O, Venables E, Polack T, Sheikh MS. Pharmacokinetics and safety of ketolorac: Following single

Srinivas NR. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3)：169-178

178

intranasal and intramuscular administration in healthy volunteers. J Clin Pharmacol 2007, 47: 13 – 18.

23. Dale O, Nilsen T, Loftsson T, Hjorth Tonnesen H, Klepstad P, Kaasa S, Holand T, Djupesland PG. Intranasal midazolam: a comparison of two delivery devices in human volunteers. J Pharm Pharmacol 2006; 58(10): 1311 – 1318.

24. McCormick AS, Thomas VL, Berry D, Thomas PW. Plasma concentrations and sedation scores after nebulised and intranasal midazolam in healthy volunteers. Br J Anaesth 2008; 100(5): 631 – 636.

25. Furubayashi T, Kamaguchi A, Kawaharada K, Masaoka Y, Kataoka M, Yamashita S, Higashi Y, Sakane T. Evaluation of the contribution of the nasal cavity and gastrointestinal tract to drug absorption following nasal application to rats. Biol Pharm Bull 2007; 30(3): 608 – 611.

26. Srinivas NR, Shyu WC, Ferreira I, Whigan D, Chang SY, Mangold B, Greene D, Barbhaiya RH. Safety, dose proportionality, and bioavailability of BMS-181885, a 5-HT1 agonist, following intranasal and intravenous administration to humans. J Applied Ther Res 1999; 2: 243 – 251.

27. Wermeling DP, Miller JL, Archer SM, Rayens MK, Rudy AC. Pharmacokinetics, bioequivalence, and spray weight reproducibility of intranasal butorphanol after administration with 2 different nasal spray pumps. J Clin. Pharmacol 2005; 45: 969 – 973.

28. Newman SP, Pitcairn GR, Dalby RN. Drug delivery to the nasal cavity: in vitro and in vivo assessment. Crit Rev Ther Drug Carrier Syst 2004; 21(1): 21 – 66.

————————————————————————————————————————————————————————

New Book Introduction Drug Metabolism in Drug Design and Development Edited by Donglu Zhang, Mingshe Zhu and W. Griffith Humphreys Published by John Wiley & Sons, Inc., Hoboken, New York

Information on the metabolism and disposition of candidate drugs is a critical part of all aspects of the drug discovery and development process. Drug metabolism, as practiced in the pharmaceutical industry today, is a complex, multidisciplinary field that requires knowledge of sophisticated analytical technologies and expertise in mechanistic and kinetic enzymology, organic reaction mechanism, pharmacokinetic analysis, animal physiology, basic chemical toxicology, preclinical pharmacology, and molecular biology. With chapters contributed by experts in their specific areas, this reference covers:

*Basic concepts of drug metabolism *The role of drug metabolism in the pharmaceutical industry *Analytical techniques in drug metabolism *Common experimental approaches and protocols Drug Metabolism in Drug Design and Development emphasizes practical considerations such as

the data needed, the experiments and analytical methods typically employed, and the interpretation and application of data. Chapters highlight facts, common protocols, detailed experimental designs, applications, and limitations of techniques.

This is a comprehensive, hands-on reference for drug metabolism researchers as well as other professionals involved in pre-clinical drug discovery and development.

Xu YY et al. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3):179-201

179

Asian Journal of

Pharmacodynamics and Pharmacokinetics

ISSN 1608-2281

Copyright by Hong Kong Medical Publisher

Publisher Homepage: www.hktmc.com

Research on bioresponse of active compounds of Strychnos nux-vomica L. Yan-Yan Xu1,2, Duan-Yun Si2, Chang-Xiao Liu1* 1 State Key Laboratories of Pharmacokinetics and Pharmacodynamics, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, China 2 School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China

Abstract The genus Strychnos is very well known as the plants providing one of the most famous poisons, which is logically called strychnine. The pantropical Strychnos genus comprises about 200 species in the world. In China, Semen Strychni is used generally after processing (such as parching in a sand bath) to reduce its toxicity. Ethnopharmacologically, the seeds of Strychnos nux-vomica L. is used in the traditional Chinese medicine. The dried seeds of this plant are used for relieving pain, promoting blood circulation and curing indigestion. They are included as an ingredient in many analgesic prescriptions of traditional Chinese medicine. In Africa and in Asia, Strychnos genus is important for its reputation as a remedy against snakebites and poisonings. In West and Central Africa, Strychnos species are a major group of arrow poison adjuvants. In Europe, S. nux-vomica came early as seeds and later its wood was imported as a ‘lignum colubrinum’; they were used in the treatment of a variety of ailments and subsequently the seeds of this Strychnos have been the main source of the alkaloid strychnine. Alkaloids are the main bioactive ingredients in Strychnos nux-vomica; they are also responsible for the pharmacological and toxic properties possessed by Strychnos nux-vomica. In this review paper, we introduced the ethnobotany and ethnopharmacology, chemical, pharmacological, pharmacodynamic, pharmacokinetic, metabolomic and toxicological studies, and clinical response of Strychnos nux-vomica L. and its alkaloids.

Key words alkaloids; chemistry; ethnobotany; ethnopharmacology; metabolomics; pharmacology; pharmacodynamics; pharmacokinetics; Strychnos nux-vomica L.; toxicology

Article history Received 26 August 2008; Accepted 24 March 2009 Publication data Pages: 23; Tables:2; Figures:8; References: 76; Paper ID 1608-2281-2009-09030179-23 *Corresponding author Professor Chang-Xiao Liu, Research Center for New Drug Evaluation, Tianjin Institute of

Pharmaceutical Research, Tianjin 300193, China. Tel:+86-22-23006863 E-mail: liuchangxiao @163.com

Introduction

The genus Strychnos is very well known as the plants providing one of the most famous poisons. Because of their

toxicity, many of these species have been used as arrow poisons or in ordeals. The Strychnos genus comprises about 200 species in the world and can be subdivided into three geographically separated groups of species:

Xu YY et al. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3):179-201

180

one in Central and South America (at least 73 species), one in Africa (75 species), and one in Asia including Australia and Polynesia (about 44 species).

In China, Semen Strychni， the dried seeds of Strychnos nux-vomica L. (Fig 1), S. hainanensis Merr et Chum, S. pierriana A. W. Hill or S. confertifora Merr et Chum is used, generally after processing to reduce its toxicity in the traditional Chinese medicine.[1] This herb was recorded in Bencao Gangmu edited by Li Shi-Zheng in Ming Dynasty. The drug was listed as the third category with the toxic herbs, its biological effects (pharmacology and toxicity effects) is a dose-dependent relationship. Ethnopharmacologically, the property and taste are bitter and cold. The meridians are into heart, liver and spleen. The functions are to invigorate blood, stop pain, move stagnation, and reduce edema. In Chinese medicine prescriptions (such as Biqi capsule), the processed Semen Strychni is frequently used as an important ingredient in traditional medicine to promote blood circulation and remove blood stasis. After this process, the original sixteen strychnos alkaloids decreased significantly in Semen Strychni. Now, Semen Strychni was listed in Pharmacopoeia of the People's Republic of China[1,2]. Modern studies showed that Strychnos nux-vomica is used in the therapy of liver cancer. In this review paper, we introduced the ethnobotany and ethnopharmacology, chemical, pharmacological, pharmacodynamic, pharmacokinetic, metabolomic and toxicological studies, and clinical response of Strychnos nux-vomica L. and its alkaloids. Ethnobotany and Ethnopharmacology

The genus Strychnos is very well known as the plants providing one of the most famous poisons, which is logically called strychnine. The pantropical Strychnos genus comprises about 200 species and can be subdivided into three geographically separated groups of species: one in Central and South America (at least 73 species), one in Africa (75 species), and one in Asia including Australia and Polynesia (about 44 species). Belonging to the Loganiaceae family, they are found as erect or climbing shrubs, lianas or trees.[3,4]

In China, the seeds of Strychnos nux-vomica L. is used, generally after processing (such as parching

in a sand bath) to reduce its toxicity. The dried seeds of this plant are used for relieving pain, promoting blood circulation and curing indigestion. They are included as an ingredient in many analgesic prescriptions of traditional Chinese medicine. Such a use can induce accidents, even after processing. In this country, strychnine poisoning should be included in the differential diagnosis in any patient with ‘unexplained’ muscle spasms or convulsions and such patients should be asked about the use of herbal medicines.[6] Note that a study has demonstrated the antinociceptive effects of crude alkaloid fractions of processed and unprocessed S. nux-vomica seeds in different analgesic tests in mice. This crude alkaloid fraction seemed to be about 1000 times more potent than morphine. [7]

Fig1. Strychnos nux-vomica L. and its seeds

http://www.yiyanfang.com/shipu/shicaigongxiao/maqianzi_13780/

In Southeast Asia, arrow and dart poisons have been extensively utilized. The major source of poison throughout much of the region, from Burma to China and Indonesia is the latex of the highly toxic cardenolide-bearing Antiaris toxicaria (Moraceae), but the roots or stem barks of various species of Strychnos are another important source, and among them are S. ignatii and S. nux-vomica. An analysis of some dart-poisons from Malaysia, the centre of poisoned arrows and darts in Southeast Asia, has confirmed that their main active compounds are cardenolides from A. toxicaria and Strychnos alkaloids, probably from S. ignatii, the most common Strychnos in such poisons . [8] The leaves and fruits of some species (S. nux-vomica and S. potatorum in India, S. ignatii in the Philippines) have been used as fish poisons.[9]

In Europe, S. nux-vomica came early as seeds

Xu YY et al. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3):179-201

181

and later its wood was imported as a ‘lignum colubrinum’; they were used in the treatment of a variety of ailments and subsequently the seeds of this Strychnos have been the main source of the alkaloid strychnine. The seeds of S. ignatii also reached Europe and were used like those of S. nux-vomica. For more details about Strychnos medical uses, one can consult.[3,9,10]

In West and Central Africa, Strychnos species are a major group of arrow poison adjuvants, but their place in the hierarchy of African hunting poisons is, however, secondary in comparison with that of some plants such as Strophantus, the use of Strychnos species being limited locally. [3] Their roots are used especially in the equatorial forest regions of Central Africa. Most of the African Strychnos-based arrow poisons contain the wellknown convulsant strychnine or related alkaloids. Generally, it is the distinctively red-coloured roots of S. icaja that are used. The plant, like other Strychnos species, such as S. densiflora Baill., S. samba Duvign. and S. angolensis Gilg, has also been widely used as an ordeal poison.[11] Indeed, the importance of the genus Strychnos as a trial by ordeal poison is higher than as a hunting poison. Until the latter part of the 19th century, ordeals were widely used for determining innocence or guilt. The general principle of this type of ordeal was that if, after being given the poison to eat or drink, the subject rejected it, the person was assumed to be innocent. S. usambarensis Gilg is also used as an arrow poison in Africa, but it does not contain strychnine and was found to behave just like a good curare. This latter plant will be described further in the curare part of this manuscript. The fruit of different species, and especially S. aculeata, are known for their use as fish poison . [12]

In Africa and in Asia, Strychnos genus is important for its reputation as a remedy against snakebites and poisonings. The reputed emetic and tonic (bitter) properties no doubt play an important part in the use of Strychnos in stomach, abdominal and intestinal complaints as well as in the treatment of worms and parasites. Strychnos also finds a use against fevers in both Africa and Asia. Moreover, this genus was implicated in the treatment of ulcers, wounds, and swellings, in skin troubles including leprosy, and in the treatment of more specific diseases like cholera and rabies. S. icaja is used in

different regions in Africa to treat chronic malaria.[3] Chemical studies

Alkaloids are the main bioactive ingredients in

Strychnos nux-vomica; they are also responsible for the pharmacological and toxic properties possessed by Strychnos nux-vomica. Alkaloids are 1.5～5% of the seeds, Strychnine is about 35～50% in total alkaloids of the seed of Strychnos nux-vomica L.. Brucine is also 35～ 50% in total alkaloids. Colubrine and 16-hydroxycolubrine, pseudo- strychnine, vomicine, and loganin are presentred in the seeds. Mavacurine, novacine, icajine, α-colubrine, β-colubrine, isostrychnine, pserdo- strychnine, seudobrucine, 16-hydroxy-β-colubrine, 18-hydroxy-sungucine, 18-hydroxy- isosungucine and vomicine. Isobrucine, isobrucine N-oxide, isostrychnine N-oxide, 2-hydroxy-3-methoxy- strychnine are isolated from processed Strychnos nux-vomica seeds. Additionally, cycloartenyl palmitate, fatty acid, protein and polysaccharides were isolated from the seed of Strychnos nux-vomica L. Fig 2A and 2B exhibited the chemical structures of major alkaloids.

The composition of the coagulant polysaccharide fraction from Strychnos potatorum seeds is described. This fraction comprises a 1:1.7 mixture of a galactomannan and a galactan. The structure of these polysaccharides is also discussed. In addition, the coagulant properties of the polysaccharide fractions of two other Strychnos species, innocua and nux-vomica, have been assayed.[13] This paper deals with the extraction, determination and identification of the alkaloids in differently processed products of the seeds of Strychnos nux-vomica. The relationship between processing methods and toxicities is discussed according to the comparison of acute toxicity.[14] The contents of strychnine, brucine, isostrychnine and isobrucine in different processed products of Strychnos nux-vomica were determined by TLC-densitometry. The relationship of the contents of strychnos alkaloids with processing methods was studied.[15] Thirteen alkaloids were isolated from the seeds of Strychnos nux-vomica. They were identified as strychnine, beta-colubrine, pseudostrychnine, strychnine N-oxide, brucime,

Xu YY et al. Asian Journal of Pharmacodynamics and Pharmacokinetics 2009; 9(3):179-201

182

brucine N-oxide, novacine, icajine, vomicine, isostrychnine, isobrucine, isobrucine N-oxide and isostrychnine N-oxide by chemical and spectroscopic analysis.[16]

The application of an on-l