Histopathological and immunohistochemical investigation of the preventive effect of nigella sativa exctrat on obesity induced by high fat diet in rats.

In this study, the effect of Nigella sativa (NS) extract on obesity in rats fed with high-fat diet was investigated histopathologically and biochemically. For this aim, thirty-two (32) rats were randomly separated in four groups, to be eighth (8) rats in each group, control (n=8), obesity (n=8), obesity plus NS (n=8) and NS (n=8). Control group was fed with the standard rat pellet bait. Obesity group was fed high-energy value fat-diet pellet bait. Obesity plus NS extract group was fed with high energy value diet pellet bait, additionally, NS extract was daily given the dose of 3mg/kg/rat with an orogastric gavage. NS extract group was fed with standard pellet bait, additionally, NS extract was daily given the dose of 3 mg/kg/rat with an orogastric gavage. During the experiment, the weight gaining of rats was tracked. At the end of the experiment, blood and tissue samples were taken from rats done necropsy for the biochemical and histopathologic examinations. Histopathologically, fat vacuoles and coagulation necrosis were particularly observed in centrilobular hepatocytes in the obesity group rat's liver, while in the obesity plus NS group, the liver was observed normal histologic appearance like in the control group. In the blood serum samples, alanine transaminase (ALT), aspartic transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), cholesterol, triglyceride, HDL cholesterol, LDL cholesterol and fasting blood sugar (AKS) activities were determined. It was noticed that ALP, LDH, and AKS activities in the obesity group was significantly increased according to the control group, while in the obesity plus NS extract group was quite similar to that of the control group. Triglyceride levels were significantly higher in obesity group compared to control, NS + obesity and NS group. Serum ALT levels in NS+obesity group were significantly higher than control and obesity group. In conclusion, it was shown that liver lipid degeneration was substantially prevented in rats fed with pellet bait with high energy value, given additional NS extract.