Caffeine and EGCG Alleviate High-Trans Fatty Acid and High-Carbohydrate Diet-Induced NASH in Mice: Commonality and Specificity.

Caffeine and epigallocatechin-3-gallate (EGCG), which respectively, are the main functional extracts from coffee and green tea, and present protective effects against non-alcoholic fatty liver diseases (NAFLD). These two beverages and their functional extracts are highly recommended as potential treatments for obesity and NAFLD in clinics; however, their pharmacodynamic effects and pharmacological mechanisms in non-alcoholic steatohepatitis (NASH) remain unclear. Therefore, the aim of this study was to explore the commonality and specificity of the pharmacodynamic effects and pharmacological mechanisms of caffeine and EGCG on NASH mice, which were fed with a high-trans fatty acid/high-carbohydrate (HFHC) diet. C57BL/6J mice were fed a normal diet (control group) or an HFHC diet (HFHC group) for 24 weeks. HFHC group mice were additionally treated with caffeine (75 mg/kg) or EGCG (100 mg/kg) for 6 weeks, using obeticholic acid (OCA,10 mg/kg) as a positive control group. The pharmacological effects of the drugs, including effects on glucose and lipid metabolism and liver inflammation and fibrosis, were evaluated. Gene expression in liver tissue samples from the different groups were assessed. Both caffeine and EGCG significantly reduced the liver manifestations of NASH induced by HFHC. The pathological aspects of liver lipid deposition, inflammation, and liver fibrosis in both groups were strongly ameliorated. Of note, most indexes were strongly reversed in the caffeine group, although AST activity, fasting blood glucose, and the HOMA-IR index were improved in the ECGC group. There were 714 differentially expressed genes between the caffeine and HFHC groups and 268 differentially expressed genes between the EGCG and HFHC groups. Twenty and 17 NASH-related KEGG signaling pathways were enriched by caffeine and EGCG. This study confirmed that 75 mg/kg caffeine and 100 mg/kg EGCG could significantly improve liver lipid deposition, glucose metabolism, inflammation, and fibrosis in a mouse model of NASH induced by HFHC. The bioinformatics platform we built for caffeine and EGCG in NASH disease found that the two drugs may greatly overlap in improving the mechanism related to NASH inflammation. However, caffeine may have better potential in regulating glucose metabolism and EGCG may have better potential in regulating lipid metabolism.

Effect of Fuzheng Huayu Capsule on Experimental Non-alcoholic Fatty Liver Fibrosis in Mice / 中国实验方剂学杂志

Objective:To explore the therapeutic effect of Fuzheng Huayu capsule on nonalcoholic fatty liver fibrosis induced by high trans fatty acid and high sugar diet in mice. Method:Forty SPF male C57/B6 mice were randomly divided into 4 groups （normal group， model group， Obelcholinic acid group， and Fuzheng Huayu capsule group）， with 10 mice in each group. Except 10 mice in the normal group， nonalcoholic fatty liver fibrosis was induced by high-fat and high-sugar diet for 24 weeks in the other 30 mice. From the 25th week of modeling， 4 groups received intragastric administration for 4 weeks， once a day： Fuzheng Huayu capsule group 4.8 g·kg^-1. Oxycholic acid group 10 mg·kg^-1. Model control group and normal group received the same volume of normal saline. Liver tissue and serum samples were collected at the end of the 28th week. The pathological changes of liver tissue of mice in each group were observed by hematoxylin-eosin （HE） staining， the degree of liver fibrosis was observed by Sirius red staining， the degree of lipid deposition was observed by oil red O staining， the content of hydroxypropylamine （Hyp） in liver tissue was determined by alkaline hydrolysis， and the change of triglyceride （TG） in liver tissue was detected by enzyme method. Serum alanine aminotransferase （ALT）， aspartate aminotransferase （AST） activities and fasting blood glucose （FBG） were detected by kit method， enzyme-linked immunosorbent assay （ELISA） was used to detect fasting Insulin （INS） level and calculate the changes of insulin resistance index （HOMA-IR）， liver fibrosis related mRNA and proteins of were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， Western blot and Immunohistochemistry. Result:Compared with the normal group， the liver tissue in the model group showed significant collagen fiber deposition， at mostly F2-F3 fibrosis stages， with increased number of inflammatory foci in liver tissue， obvious balloon degeneration and fatty degeneration of liver cells， significantly increased contents of Hyp and TG in liver tissue （<italic>P</italic><0.01）， significantly increased activities of ALT and AST in serum and levels of FBG， INS and HOMA-IR （<italic>P</italic><0.01）， and increased type I collagen （Col-Ⅰ）， Col-Ⅳ， <italic>α</italic>-smooth muscle agonist protein （<italic>α</italic>-SMA） and transforming growth factor-<italic>β</italic> （TGF-<italic>β</italic>） protein and mRNA in liver tissue. Compared with the model group， the collagen fiber deposition in liver tissue of mice in Fuzheng Huayu capsule group was significantly reduced， at mostly F0-F1 fibrosis stages， with significantly improved balloon-like change of hepatocytes， and significantly reduced number of inflammatory foci in lobules （<italic>P</italic><0.05，<italic>P</italic><0.01）. Compared with the model group， Fuzheng Huayu capsule can significantly reduce the content of Hyp in liver tissue， the levels of serum ALT and AST， and the expression of Col-Ⅰ， Col-Ⅳ， <italic>α</italic>-SMA and TGF-<italic>β</italic> genes and proteins in mice （<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Fuzheng Huayu capsule has a good therapeutic effect on nonalcoholic fatty liver fibrosis induced by high trans fatty acid and high sugar diet in mice.