Combination of Whole Grapeseed Flour and Newly Isolated Kefir Lactic Acid Bacteria Reduces High‐Fat‐Induced Hepatic Steatosis

Scope This study aims to determine the separate and combined effect of a prebiotic (catechin‐rich wine grapeseed flour, GSF) and a probiotic (newly isolated kefir lactic acid bacteria, LAB) on hepatic steatosis of obese mice. Methods and results High‐fat (HF)‐induced obese mice are fed a HF diet containing 6% microcrystalline cellulose (MCC, control), 10% GSF, orally administrated LAB, or a combination of GSF and LAB for 9 weeks. There is a significant reduction of body weight gain and liver weights, plasma insulin concentrations, and HOMA‐IR in all experimental groups compared to control. Total lipid content, triglyceride, and low‐density lipoprotein (LDL)‐cholesterol concentrations of the liver are also significantly lowered. The combination of GSF and LAB further significantly affects cecum propionate content, plasma aspartate aminotransferase (AST/GOT), and zonulin concentrations, which is significantly correlated with hepatic lipid content. Analysis of hepatic microarray data reveals that genes related to lipid synthesis, bile acid and cholesterol synthesis, antioxidant activities, oxidative stress, inflammation, and liver function are significantly modulated following the combination of GSF and LAB. Conclusion These data suggest that amelioration of HF‐induced hepatic steatosis after consumption of GSF and LAB is partially mediated via alteration of cecum propionate and intestinal permeability, which modulates hepatic gene expression. Supplementation of flavonoid‐rich chardonnay grapeseed flour (GSF) and newly isolated kefir lactic acid bacteria (LAB) synergistically enhances cecum short‐chain fatty acid and intestinal barrier function, which alters expression of hepatic genes related to fatty acid synthesis; oxidative stress; inflammation; response to lipopolysaccharides, bile acid, and cholesterol synthesis; and liver function. Eventually, it ameliorates high‐fat‐induced insulin resistance, hepatic steatosis, and inflammation.