Solanum nigrum show anti-obesity effects on high-fat diet-fed Sprague Dawley rats in a randomized study

Abstract

Solanum nigrum also known as black night shade biosynthesizes various bioactive compounds which have various pharmacological activities including treating cardiovascular diseases, diabetes type 2 among others. To assess the anti-obesity effects of Solanum nigrum using high-fat-fed diet rats, Sprague Dawley male rats (n = 35) of weights 160–180 g were assigned randomly into seven groups comprising n = 5 rats each. Each group was fed for 11 weeks as follows: normal group (normal chow rat feed); high-fat diet control (HFD); HFD and standard drug (Orlistat 30 mg/kg bw); HFD and methanolic extract 150 mg/kgbw; HFD and methanolic extract 300 mg/kgbw; HFD and dichloromethane extract 150 mg/kgbw; HFD and dichloromethane extract 300 mg/kgbw. Body mass index and food intake were monitored per week and an oral glucose tolerance test was measured in weeks 5 and 10. Lipid profiles, liver function tests, adipose tissue, liver weights, and phytochemical analysis of Solanum nigrum were later carried out. ResultsHigh-fat diet control group rats exhibited a significant increase in body mass index (BMI) while rats administered with leaf extracts of Solanum nigrum showed a reduction in BMI. Both low dose of dichloromethane (150 mg/kgbw) and high dose of methanol extracts (300 mg/kgbw) showed a better reduction in BMI than the other treatment groups. A significant decrease (p <0.05) on low-density lipoprotein-cholesterol, triglycerides and cholesterol was observed among the rats administered with Solanum nigrum extracts compared to those of HFD control. Moreover, the HFD control group significantly increased liver and adipose tissue weights compared to other treatments groups (p<0.05). Solanum nigrum also decreased glycemic levels and normalized the hepatic enzymes of HFD control. However, food intake among the groups showed no significant difference (p>0.05). Qualitative analysis of Solanum nigrum leave extracts indicated the presence of various bioactive compounds associated with anti-obesity. ConclusionThese results validate the use of Solanum nigrum in controlling obesity.