Effect of seeds of Entada phaseoloides on chronic restrain stress in mice

BACKGROUND: Entada phaseoloides is a well-known medicinal plant traditionally used in Ayurvedic medicine for centuries. OBJECTIVE: To evaluate the anti-stress activity of seeds of E. phaseoloides in endoplasmic reticulum stress during chronic restrain stress in mice, based on our preliminary screening. MATERIALS AND METHODS: Mice (n = 6/group) were restrained daily for 6 h in 50 ml polystyrene tubes for 28 days. Methanolic extract of E. phaseoloides (MEEP) (100 and 200 mg/kg, p.o.) and standard drug, imipramine (10 mg/kg i.p.) were administered daily 45 min prior to restrain from day 22–28. Then, forced swim test (FST) was performed to assess despair behavior. Lipid peroxidation (LPO) and antioxidant enzymes Reduced glutathione (GSH), Superoxide dismutase (SOD) were measured in the hippocampus of mice. 78 kDa Glucose-regulated Protein, 94 kDa Glucose-regulated Protein, C/EBP homologous protein, Caspase-12 expression were quantified by Real Time PCR. RESULTS: MEEP significantly reduced the immobility time in FST (P < 0.001). Significant reduction of LPO (P < 0.05) level and restored antioxidant enzymes viz. GSH (P < 0.001) and SOD towards vehicle control group were observed. Down-regulation of genes GRP 78, GRP 94 (P < 0.001), CHOP and Caspase-12 (P < 0.001) as compared to the chronic restrain stress group was evident, which were upregulated following treatment. Isolation of the active components of the seeds revealed the presence of Oleic acid (1), Entadamide A (2), Entadamide A-beta-d-glucopyranoside (3) and 1-O-protocatechuoyl-β-d-glucose. CONCLUSION: MEEP altered endoplasmic reticulum stress in chronic restrain stressed mice; however, as an antidepressant it showed a weaker response.