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ANTI-DEPRESSANT ACTIVITY OF ETHANOLIC EXTRACT OF LEAVES OF

OCIMUM SANCTUM IN MICEAkshaya Alva, Seema Y, Durga Pillai, Vishnu

Raj, P.Sudhakar, H.N.Gopalakrishna, M.R.S.M Pai. Department of Pharmacology, Kasturba Medical College, Mangalore

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INTRODUCTION

Depression is a mental state characterized by feelings of sadness, despair and discouragement. Depression ranges from normal feelings of the blues through dysthymia to major depression.

Prevalence rate: Prevalence of depression alone was at 3.2%. In conditions like diabetes mellitus – 2%, angina pectoris – 4.5%

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OCIMUM SANCTUM (OS)

Family: Labiatae

Common name: tulsi

Chemical constituents: Ethonolic leaf extract of OS contains 2.5% Ursolic acid (anti-inflammatory, antioxidant). Besides this it contains alkaloid, glycosides & tannins, ascorbic acid & carotene, flavanoids (orientin, vicenin) and eugenol, cirsilineol, apigenin.

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BACK GROUND In our laboratory NR-ANX-C (polyherbal product) has shown dose dependent anxiolytic & antidepressant effect in rats (Gopalakrishna HN et al., 2006).

Ocimum sanctum (OS) is one of the components of NR-ANX-C.

To evaluate the contribution of OS in antidepressant effect of NR-ANX-C.

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OBJECTIVE

To evaluate the antidepressant activity of acute administration of ocimum sanctum in mice

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ANIMALS:– Adult Albino mice (Swiss strain) weighing 25-30 grams. Maintained under standard conditions.Drugs:- Vehicle - 1% gum acacia Standard drug – Imipramine Test drug – Ocimum sanctum dry powder was supplied by M/s Natural Remedies, Bangalore, India).The study was approved by the Institutional Animal Ethics Committee.

MATERIALS AND METHODS

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EXPERIMENTAL DESIGN

Table 1: Drug treatment

All the drugs were given 1 hr prior to the experiment

Groups(n=6)

Treatment Route of administration

DOSE

1 Control (gum acacia)

P.O 10.0 ml/kg

2 OS P.O 1.75 mg/kg

3 OS P.O 4.25 mg/kg

4 OS P.O 8.50 mg/kg

5 Imipramine P.O 10.0 mg/kg

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EVALUATION OF ANTIDEPRESSANT ACTIVITY

Forced swim test (Porsolt et al)

Mice was placed in 5 letres beaker filled with water up to 15cm.

Duration of immobility was recorded in last 4 min of 6 min test.

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Tail suspension test (Porsolt et al)

Mice was hanged on plastic string 75 cm above table top.

Immobility duration is recorded for 8 min.

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STATISTICAL ANALYSIS

All the results were expressed as mean ± Standard error (SEM).

Analyzed by using one-way ANOVA, followed by Dunnett’s t- test.

P < 0.05 was considered as statistically significant.

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RESULTS

Table 2: Effect of Ocimum sanctum on immobility period in forced swim test.GROUP

(n=6)TREATMENT DOSE IMMOBILITY

TIME [sec](MEAN ± SEM)

1 Control 10 ml/kg 120 ± 3.94

2 OS 1.75 mg/kg 113 ± 3.90

3 OS 4.25 mg/kg 104.5 ± 1.8

4 OS 8.5 mg/kg 95 ± 2.51*

5 Imipramine 10 mg/kg 62.33 ± 12**

All values are expressed as mean ± SEM *P < 0.05, **P < 0.01

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RESULTS

Table 3: Effect of Ocimum sanctum on immobility period in tail suspension test. GROUP

(n=6)TREATMENT DOSE IMMOBILITY TIME

(sec)MEAN ± SEM

1 Control 10 ml/kg 247.17 ± 2.91

2 OS 1.75 mg/kg

239.5 ± 4.90

3 OS 4.25 mg/kg

237.17 ± 5.91

4 OS 8.5 mg/kg 225.00 ± 2.76

5 Imipramine 10 mg/kg 187.00 ± 16.68**All values are expressed in mean ± SEM **P < 0.01

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Discussion

Forced swim test showed significant antidepressant activity at a dose of 8.5 mg/kg when compared to control.

Tail suspension test did not show any significant result.

The present study shows the possible antidepressant like activity of Ocimum Sanctum in mice.

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Ursolic acid the active constituent present in Ocimum sanctum L., has been found to be largely responsible for the therapeutic potentials of Tulsi.

The precise mechanism by which it produces antidepressant like activity is not known.

Further study has to be done to elucidate exact mechanism of action

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CONCLUSION

The present study indicates the possible antidepressant like activity of Ocimum sanctum at a dose of 8.5 mg/kg in mice

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REFERENCES1) Porsolt RD, Bertin A and Jalfre M. Behavioral despair

in mice: screening test for antidepressants. Archives of international pharmacodynamics 1977; 229:327-336.

2) Steru L, Chermat R, Thierry B, Simon P, Psychopharmacology 1985;85:367-370.

4) Preclinical evaluation of antidepressant activity of NR-ANX-C in mice. N.Misra, R.Shastry, H.N.Gopalakrishna, M.R.S.M.Pai. Indian J Pharmacology 2003;35(3):192.

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4) H.N.Gopalakrishna, R.B.Sangha, N. Misra, M.R.S.M.Pai. Antianxiety activity of NR-ANX-C, a polyherbal preparation in rats. Indian J Pharmacology. 2006; 38(5): 330-335.

5) Dinesh. D, Sharma A. Evaluation of antidepressant-like activity of glycyrrhizin in mice. Indian J Pharmacology 2005;37:390-394.

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