Antidepressant Effect of Hedyotis corymbosa Extract in Olfactory Bulbectomy Rats

Background: Hedyotis corymbosa Linn. (family: Rubiaceae) has been used in the Indian indigenous system of medicine, Ayurveda, for treatment of various health aliments. Objectives: The present study was undertaken to evaluate the antidepressant activity of methanolic extract of whole plant of H. corymbosa (MHC) in olfactory bulbectomy rats. Materials and Methods: MHC was prepared and standardized to gallic acid by high‑performance thin‑layer chromatograph method. Effects of 14 days oral treatment of fluoxetine (30 mg/kg) and three doses of MHC (50, 100, and 200 mg/kg) were evaluated on olfactory bulbectomy (OBX)‑induced alterations in behavioral and biochemical parameters in rats. Results: MHC treatment reversed the OBX‑induced behavioral abnormalities such as increased exploratory activity in open‑field paradigm and decreased feeding latency time in novelty‑suppressed feeding test. Serum cortisol levels were restored near to normal by the MHC treatment. Further, treatment of MHC prevented the OBX‑induced decline of brain levels of serotonin and nor‑adrenaline in dose‑dependent manner. Conclusion: MHC prevents behavioral and neurochemical changes in OBX‑induced depression in rats. These results demonstrate the antidepressant effect of H. corymbosa and support its folklore claim.