OBJECTIVE

To explore the mechanism of purple sweet potato anthocyanins through NF-κB pathway in attenuating steatohepatitis induced by high fat diet combined with carbon tetrachloride in rats.

METHODS

Seventy male rats were randomly divided into control group( n = 10) and high-fat diet group( n = 60), models were prepared by highfat diet and intraperitoneal injection of carbon tetrachloride and olive oil( 50 : 50) 2 mL/kg, two times a week. After 10 weeks of feeding, the weight variations of all rats were tested before and after modeling. The colorimetric technique was used to test the concentration of serum ALT, AST, TG, and TC. A total of 58 rats were succeeded in modeling, the random choice of 50 rats were divided into model group, purple sweet potato anthocyanin low dose group( 60 mg/kg), middle dose group( 120 mg/kg), high dose group( 240 mg/kg), positive drug group( 150 mg/kg), 10 rats in each group. After 8 weeks of continuous administration, the method of colorimetric technique was used to test the concentration of ALT, AST, TG, TC, HDL and LDL. The method of ELISA kit was used to test the levels of the pro-inflammatory factors TNF-α, IL-1β and the levels of the anti-inflammatory IL-4, IL-13. The Real-time PCR was used to test the expression of TNF-α, IL-1β, IL-4, IL-13, PPAR-γ and HMGB-1 mRNA of rats liver. The western blotting method was adopted to test the level of IκB phosphorylation in liver tissues as well as the PPAR-γ and HMGB-1 protein expression.

RESULTS

After modeling, the body weight of rats increased( P < 0. 05), the concentration of serum insulin AST, ALT, TG, TC, and LDL all increased significantly( P < 0. 05), the concentration of HDL decreased obviously( P < 0. 05). Compared with control group, the expression of TNF-α, IL-1β and HMGB-1 in model group were increased significantly( P < 0. 05), the expression of IL-4, IL-13 and PPAR-γ were decreased significantly( P < 0. 05), the expression of pIκB and NF-κB in the model group increased significantly( P < 0. 05). Compared with the model group, the expression level of NF-κB in the high dose purple sweet potato anthocyanin group decreased obviously, and the phosphorylation degree of IκB decreased( P < 0. 05), the mRNA expression of TNF-α, IL-1β and HMGB-1 in liver tissue was significantly decreased( P < 0. 05), and the mRNA expression of IL-4, IL-13 and PPAR-γ were significantly increased( P < 0. 05). The purple sweet potato anthocyanin low dose group, middle dose group, high dose group and positive drugs group all improved the above indexes in different degrees. The effect of the high dose group was significantly higher than that of the low dose and medium dose group, but equivalent to that of the positive drug group.

CONCLUSIONS

Purple sweet potato anthocyanins through NF-κB pathway have a role in attenuating steatohepatitis induced by high fat diet combined with carbon tetrachloride in rats.