Effect of white wheat bread and white wheat bread added with bioactive compounds on hypercholesterolemic and steatotic mice fed a high-fat diet

Hypocholesterolemic Effect of the Lignin-Rich Insoluble Residue of Brewer's Spent Grain in Mice Fed a High-Fat Diet

Insoluble residue (INS) is a lignin-rich fraction of brewer's spent grain (BSG) that also contains β-glucan and arabinoxylan, the major constituents of dietary fiber. We investigated the effects of INS in diet-induced obese mice in terms of lipid metabolism and metabolic diseases. Male mice (C57bl6) were fed a high-fat diet (HFD), a HFD + 20% INS, a HFD + 20% cellulose (CEL), a HFD with a combination of 20% INS-CEL (1:1), or a control diet for 14 weeks. Insulin and glucose tolerance tests were performed after 12 weeks. Fasting plasma lipids, bile acid, and fecal bile acid were measured after 14 weeks of feeding, and tissues were collected for gene expression analysis. Body weight gain was significantly reduced with all fibers, but only INS and INS-CEL decreased fasting plasma low-density lipoprotein cholesterol and total cholesterol compared to HFD. CEL and INS-CEL significantly improved insulin resistance. Fecal bile acids were significantly increased by all fibers, but there was no change in plasma bile acid. Clostridium leptum was increased with all fibers, but universal bacterial diversity was only with INS and INS-CEL. In addition, INS significantly increased the abundance of Bacteriodes, while CEL decreased Atopobium and Lactobacillus. INS feeding significantly upregulated various genes of cholesterol and bile acid metabolism, such as Srebp2, Hmgcr, Ldlr, Cyp7a1, Pparα, Fxr, and Pxr, in the liver. INS, INS-CEL, and CEL significantly attenuated liver steatosis. Our results suggest that INS from BSG induced beneficial systemic changes in mice via gut microbiota, bile acids, and gene expression in the liver.

Extruded sorghum (Sorghum bicolor L.) reduces metabolic risk of hepatic steatosis in obese rats consuming a high fat diet

The study investigated the effect of extruded sorghum flour (ESF) in a high fat diet (HFD) on biometric measurements and hepatic lipogenesis. Male Wistar rats were fed a normal diet (AIN-93M), HFD, HFD plus ESF replacing 50% cellulose and 100% corn starch (HFDS50), or HFD plus ESF replacing 100% cellulose and 100% corn starch (HFDS100) for eight weeks. ESF reduced the body mass index and liver weight of obese rats. Additionally, ESF reduced hepatic lipogenesis by increasing adiponectin 2 receptor gene expression and gene and protein expressions of peroxisome proliferator-activated receptor α (PPARα), while reducing the gene expression of sterol regulatory element-binding transcription factor 1. Molecular docking analysis revealed the affinity of ESF compounds (luteolinidin, apigeninidin, 5-methoxy-luteolinidin, and 7-methoxy-apigeninidin) with the PPAR-α receptor. Histological analysis confirmed the decreased grade of hepatic steatosis in obese rats. These data indicate the potential of ESF to reduce metabolic risk of hepatic steatosis associated with lipogenesis and obesity.