Keywords: African sleeping sickness n Chagas’ disease n Leishmania n leishmaniasis n Trypanosoma

Foreword

Special FocuS: TrypanoSomaTid diSeaSeS

Neglected diseases such as leishmaniasis, human African trypanosomiasis (HAT), and Chagas disease are major causes of morbidity and mortality in resource-limited countries. The mortality associated with these infections, caused by trypanosomatid parasites Leishma-nia and Trypanosoma species, is largely due to lack of accessibility and availability of treat-ment and increasing resistance by these para-sites to the few available drugs. There are lim-ited chemo therapeutic options available, and these are often complicated by severe adverse reactions and high toxicity.

Leishmaniases are diseases caused by vari-ous species of the protozoan genus, Leishma-nia. Clinical manifestations of these diseases in humans are classified as: visceral, diffuse cutaneous, subcutaneous, cutaneous and recid-ivans leishmaniasis. Visceral leishmaniasis and cutaneous leishmaniasis are, however, the main clinical forms of the disease in humans. It has been estimated that approximately 12 mil-lion people are currently infected with the disease and almost 350 million people are at risk of infection in over 88 countries. Current chemotherapeutics for leishmaniasis include antimony-based drugs, amphotericin B and pentamidine, but these drugs have adverse side effects and drug resistance is emerging.

HAT, also known as ‘sleeping sickness’, is caused by Trypanosoma brucei. There are two sub-species of T. brucei, Trypanosoma brucei rho-desiense and Trypanosoma brucei gambiense that cause the two different forms of the disease. T. b. rhodesiense is found in southern and eastern Africa, while T. b. gambiense is found in west-ern, central and some parts of eastern Africa. T. b. gambiense now accounts for approximately 90% of all reported cases of sleeping sickness. All the clinically available chemotherapeutic

HAT drugs have been noted to be ineffective, although they also have severe side effects.

Chagas disease (also known as American trypanosomiasis) is caused by Trypanosoma cruzi and affects over 18 million people in tropical and subtropical America. In humans, symptoms of the disease include fever, swell-ing, as well as heart and brain damage, usually leading to death. There is currently no effective treatment for this disease.

Because of the low tolerability and limited accessibility of current chemotherapeutic regi-mens for these parasitic protozoal diseases, it is necessary to continue the search for adequate therapeutics for these neglected, debilitating diseases. In this special issue of Future Medicinal Chemistry [1–12], several complementary areas of research are presented, including identifica-tion of new therapeutic targets, novel mecha-nisms of activity, high-throughput screening of small-molecule libraries, de novo synthesis and optimization of new anti parasitic scaffolds, as well as in silico quantitative structure–activity relationship and molecular docking investiga-tions. Current active research in trypanosma-tid infections, as presented in this special issue, will hopefully lead to safer, more effective, less costly and more widely available treatments for these parasitic diseases in the near future.

Financial & competing interests disclosureThe author has no relevant affiliations or financial involve-ment with any organization or entity with a financial inter-est in or financial conflict with the subject matter or materi-als discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert t estimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Trypanosomatid disease drug discovery and target identification

“Current active research in trypanosomatid infections, as presented in this special issue, will hopefully lead to saver, more effective, less costly and more widely available treatments for these

parasitic diseases in the near future.”

William N SetzerDepartment of Chemistry, University of Alabama in Huntsville, Huntsville, AL 35899, USA E-mail: wsetzer@chemistry.uah.edu

1703ISSN 1756-891910.4155/FMC.13.142 © 2013 Future Science Ltd Future Med. Chem. (2013) 5(15), 1703–1704

For reprint orders, please contact reprints@future-science.com

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Foreword | Setzer

Future Med. Chem. (2013) 5(15)1704 future science group