Anxiolytic and antidepressant potentials of the trichomes of Mucuna pruriens

Abstract Background The medicinal plant Mucuna pruriens , is well known for its neuropharmacological properties but there is a dearth of literature information about how the trichomes specifically affect anxiety and depression. This study aimed to evaluate the behavioural, neurochemical, and histopathological potentials and the anxiolytic a s well as the antidepressant potential of M . pruriens trichome extracts in male Wistar rats. Method Mucuna pruriens pods were collected at Gbolasere Farms in Sagamu, Ogun State, Nigeria. The sample was identified and authenticated; a specimen was deposited at the Herbarium section with voucher specimen number IFE 18235. Forty-two (42) male Wistar rats were divided into seven groups , after which they received treatment with 200 µL or 400 µL doses of either aqueous or methanolic M . pruriens trichome extracts. The tail suspension and open field tests were used to investigate the anxiolytic and antidepressant qualities. Immunohistochemical analysis was used to quantify serotonin expression in brain and skin tissues, while histological evaluations assessed potential structural modifications. Results Rats treated with extractsexhibited a significant increase in grooming frequency ( p <0.05), indicating reduced anxiety-like behaviour. Rearing activity was also elevated, further supporting an anxiolytic effect. All extract-treated groups showed significantly shorter immobility time in the tail suspension test (p<0.05), indicating antidepressant-like action. While brain serotonin levels showed a dose-dependent decrease in the range 141.12-212.33 µL, the expressionof serotoninby the skin tissue peaked in the 400 µL aqueous extract group (143.91 µL). Serotonin receptor modulation was validated by histopathological investigation, which did not reveal any signs of neurotoxicity. Conclusion This study has shown trichomes of Mucuna pruriens to exhibit strong antidepressant and anxiolytic properties, most likely due to serotonergic regulation. These results in the study highlight their potential as natural remedies for mood disorders, which calls for more pharmacological research.