Favorable effects of Anethum graveolens on liver oxidative stress and cholesterol 7 alpha-hydroxylase levels in non-alcoholic fatty liver disease (NAFLD) rat models

BACKGROUND: High-fat high-cholesterol diet induces a phenotype similar to non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) in humans. In NAFLD and NASH, cholesterol and bile acid metabolisms are impaired to accumulate lipids and toxic bile acids along with cholestatic hepatic damage. Recently, the use of herbal-derived cholesterol lowering products has attracted much attention as possible therapeutic strategies for NAFLD. Hence, the aim of this study was to determine the effects of an Anethum graveolens (dill) on liver cholesterol 7 alpha-hydroxylase and liver fat accumulation in rats. METHOD: Thirty-six rats were randomly divided into 6 groups (n = 6) and received normal diet (ND) or a mixture of chow diet+2% cholesterol+0.5% cholic acid + 20% corn oil as high cholesterol/fat (HC–HF) diet (NAFLD model). Animals were also treated daily with dill tablet or dill extract (300 mg/kg). At the end of the 30 days experiments, serum and liver lipid profile and liver total antioxidant capacity were determined. Cholesterol 7 alpha-hydroxylase mRNA and protein expression levels were determined in the liver and histopathological changes in liver tissues were analyzed by microscope. RESULTS: Lipid profiles significantly decreased in dill treated groups (p < 0.05). Liver total antioxidant capacity significantly (p < 0.05) increased and MDA levels markedly (p < 0.05) reduced both in dill tablet and dill extract treated groups (p < 0.05). Both types of treatments caused significant increases in liver cholesterol 7 alpha-hydroxylase gene expression (p < 0.05). Histopathological examinations showed that treatment with dill normalized the hypercholesterolemia-induced changes in liver histology. CONCLUSION: Administration of dill significantly reduced liver fat, oxidative stress and increased cholesterol 7 alpha-hydroxylase enzyme at the both mRNA and protein levels. Dill extract was found more effective than its commercially available tablet.