Lactic acid-fermented Sake lees protect against nonalcoholic steatohepatitis in mice

Background: Nonalcoholic steatohepatitis (NASH) is a common disease that may lead to hepatocellular carcinoma (HCC) through fatty liver and cirrhosis. Although the prevalence of NASH is increasing worldwide, there is no cure established thus far. Sake lees are a by-product of sake refining, with a known liver-protecting effect. Lactic acid-fermented sake lees (FSL) are a food produced by lactic acid fermentation and dealcoholization of sake lees. This product is commercially available in Japan. Although FSL has been associated with numerous functions, thus far, studies have not investigated its hepatoprotective effect. Objectives: The objectives of this study are to evaluate the hepatoprotective effects of lactic acid-fermented sake lees (FSL) in a mouse model of NASH-HCC, to assess the impact of FSL supplementation on blood glucose levels in mice with NASH, to analyze the expression of inflammatory markers in FSL-fed mice compared to controls, and to determine the overall efficacy of FSL in inhibiting the progression of NASH. Methods: For this study, we established a mouse model of NASH-HCC. Mice were placed on a high-fat diet supplemented with FSL from 10 to 14 weeks of age. We assessed the diet's efficacy in halting NASH progression compared to a control group. Results: The group fed with FSL exhibited a significant suppression in blood glucose levels and a notable inhibition of NASH progression compared to the control group. Protein analysis revealed a reduction in the expression of inflammatory markers in the FSL-fed group compared to controls. Conclusion: Ingestion of FSL may exert anti-inflammatory and blood glucose-lowering effects and inhibit NASH progression. Keywords: anti-inflammation, blood glucose, fatty liver, Sake lees