Evaluation of Effectiveness of Bioactive Principles of Mucuna pruriens Seeds Using Experimental Models of Depression Associated with Parkinsonism and Associated Neurotransmitter Turnover
Background: Mucuna pruriens Linn. (DC) seeds are natural popular remedy, clinically used for the management of Parkinson’s disease. Depression is most common non-motor symptom associated with Parkinsonism. Present study evaluates effect of bioactive constituents of the M. pruriens seeds in experimental models of depression associated with Parkinsonism. Methods and Findings: Effect of 14 days treatment of isolated levodopa (ILD), alkaloid fraction (AF) and amino acid fraction (AAF) of the M. pruriens seeds were investigated in the catalepsy test, forced swim test, rotarod test and locomotor activity test after haloperidol challenge in mice. Further, the effects of Riboxetine, Bromocriptine and Fluoxetine were also studied in all these tests. The level of mice brain noradrenaline, dopamine and serotonin were assessed after 14 days treatment of all groups of mice. 14 days treatment of ILD (100 mg/kg, 200 mg/ kg, p.o.) AF (200 mg/kg, 400 mg/kg, p.o.) produced significant (P<0.001) reversal of haloperidol induced catalepsy, depression and motor performance along with rise in brain noradrenaline, dopamine and serotonin in mice. Reboxetine (1 mg/kg, i.p.) and Bromocriptine (2 mg/kg, i.p.) also showed similar effect except action on serotonin level. However, AAF (200 mg/kg, 400 mg/kg, p.o.) and did not significantly modify haloperidol induced catalepsy, depression and motor performance in mice. Fluoxetine (20 mg/kg, i.p.) also failed to reverse any effect of haloperidol in experimental models except it was potentiated haloperidol induced catalepsy in mice. AAF and Fluoxetine caused significant (P<0.001) reversal of haloperidol induced decrease in brain serotonin without modification of noradrenaline and dopamine level in mice. Conclusion: The behavioral and biochemical results of the present study indicate that ILD and AF of M. pruriens seeds have noradrenergic, dopaminergic and serotonergic system mediated protective action in experimental models of depression associated with Parkinsonism. Further clinical study requires to validating these findings. In addition, this study also provides evidence of protective action of Bromocriptine and Reboxetine. This study also confirms controversy action of an antidepressant fluoxetine in cataleptic depression
