The Effect of Hydro-Alcoholic Extract of Nigella sativa on Bmp7 and Bmp8b Expression in Rats Fed with a High-Fat Diet

Background: Bone morphogenetic protein7 (BMP7) and bone morphogenetic protein 8b (BMP8b) can induce browning of white adipose tissue. Objectives: The present study aimed to investigate the antioxidative effects of hydro-alcoholic extract of Nigella sativa on the repair of oxidative damage caused by a high-fat diet. Also, Bmp7 and Bmp8b gene expressions were investigated on white adipose tissue of the rats and then compared with metformin effects. Methods: Eighty rats were divided into two groups of prevention and treatment; then each set was divided into four sub-groups based on the administered diet (i.e., ordinary, fat, metformin, and extract of Nigella sativa). Lipid profile, paraoxonase1, malondialdehyde (MDA), HDL, and antioxidant capacity were measured in serum samples, and relative Bmp7 and Bmp8b gene expressions were calculated in white adipose tissue. Results: For both prevention and treatment sets, the weight of rats who received a high-fat diet decreased more compared to those in the normal diet group. The weight of rats who received metformin or nigella extract was also decreased compared to the high-fat diet group. MDA was also increased, but total antioxidant capacity and catalase were decreased in rats of the high-fat diet group compared to the normal diet group. MDA was also declined in nigella receiving rats, but liver PON1 activity, total antioxidant capacity, and catalase were increased, compared to the second group (P < 0.05). In the prevention and treatment set, Bmp8b gene expression was increased in the metformin and Nigella sativa groups, whereas it was decreased among those who received a high-fat diet. Bmp7 gene expression was decreased in the high-fat diet set, but metformin and Nigella sativa extract didn’t influence Bmp7 gene expression. Conclusions: This study demonstrated that Nigella sativa extract has a protective role against oxidative stress in a high-fat diet.