The influence of hydroalcoholic extract of Melilotus officinalis on lipid indices of blood serum in adult male rats under chronic stress

This study was hypothesized to evaluate the beneficial effects of Melilotus officinalis extract on blood lipid indices in adult male rats under chronic immobility stress. In the present study, 40 male Wistar rats were randomly divided into 5 groups of 8 (n=8) including: Control (intact), sham (under chronic stress receiving normal saline), and treatment (under chronic stress receiving M. officinalis extract at doses of 25, 50, and 100 mg/kg). To induce chronic immobility stress, the animals were placed in a restraint device for 2 hours daily for 21 days. The plant extract was injected intraperitoneally daily for 21 days, 30 min before induction of chronic stress. At the end, after deep anesthesia, the blood samples were taken out via cardiac puncture. Blood sera were used to evaluate lipid indices. In the sham group compared to the control, a significant increase was observed in triglyceride (P<0.001), total cholesterol (P<0.05), and VLDL (P<0.05) values. A dose of 100 of plant extract caused a significant decrease in triglyceride (P<0.001), LDL (P<0.05), and VLDL (P<0.01) and an increase in HDL (P<0.01) values. A dose of 50 of plant extract significantly lowered total cholesterol (P<0.001), triglyceride (P<0.001), and LDL (P<0.001) values. Meanwhile, a dose of 25 of plant extract caused a significant decrease in total cholesterol (P<0.01), triglyceride (P<0.001), and LDL (P<0.01) values. M. officinalis extract has the ability to improve blood lipid indices in animals under chronic stresses.