Dietary Combination of Fish Oil and Soy beta-Conglycinin Inhibits Fat Accumulation and Reduces Blood Glucose Levels by Altering Gut Microbiome Composition in Diabetic/Obese KK-Ay Mice

Dietary fish oil containing n-3 polyunsaturated fatty acids provides health benefits by lowering lipid levels in the liver and serum. beta-Conglycinin (beta CG) is a major constituent protein in soybean with many physiological effects, such as lowering blood triglyceride levels, preventing obesity and diabetes, and improving hepatic lipid metabolism. However, the combined effects of fish oil and beta CG remain unclear. Here, we investigated the effects of a dietary combination of fish oil and beta CG on lipid and glucose parameters in diabetic/obese KK-Ay mice. KK-Ay mice were divided into three groups: control, fish oil, and fish oil + beta CG; these groups were fed a casein-based diet containing 7% (w/w) soybean oil, a casein-based diet containing 2% (w/w) soybean oil and 5% (w/w) fish oil, and a beta CG-based diet containing 2% (w/w) soybean oil and 5% (w/w) fish oil, respectively. The effects of the dietary combination of fish oil and beta CG on blood biochemical parameters, adipose tissue weight, expression levels of fat-and glucose metabolism -related genes, and cecal microbiome composition were evaluated. The total white adipose tissue weight (p < 0.05), levels of total serum cholesterol (p < 0.01), triglyceride (p < 0.01), and blood glucose (p < 0.05), and expression levels of fatty acid synthesis-related genes (including Fasn (p < 0.05) and Acc (p < 0.05)), and glucose metabolism-related genes (such as Pepck (p < 0.05)) were lower in the fish oil and fish oil + beta CG groups than in the control group. Furthermore, the relative abundance of Bacteroidaceae and Coriobacteriaceae differed significantly between the fish oil + beta CG and control groups. These findings suggest that dietary intake of fish oil + beta CG may prevent obesity and diabetes, alleviate lipid abnormalities, and alter the gut microbiome composition in diabetic/obese KK-Ay mice. Further research is needed to build on this study to evaluate the health benefits of major components of Japanese food

Pigment Epithelium-Derived Factor Inhibits Lysosomal Degradation of Bcl-xL and Apoptosis in HepG2 cells

Pigment epithelium-derived factor (PEDF) has several biological actions on tumor cells, but its effects are cell-type dependent. The aim of this study was to examine the pathophysiological role of PEDF in hepatocellular carcinoma (HCC). PEDF expression was examined in various hepatoma cell lines and human HCC tissues, and was seen in various hepatoma cell lines including HepG2 cells. In human HCC tissues, PEDF expression was higher than in adjacent non-HCC tissues. In addition, serum PEDF levels were higher in HCC patients than in non-HCC patients, and curative treatment of HCC caused significant reductions in serum PEDF levels compared with pretreatment levels. In vitro experiments, camptothecin (CPT) was used to induce apoptosis and the effect of PEDF was investigated by knockdown of the PEDF gene in CPT-treated HepG2 cells. Knockdown of the PEDF gene enhanced CPT-induced apoptosis, simultaneously down-regulating Bcl-xL expression in HepG2 cells. Expression of apoptosis-related molecules and effects of bafilomycin A1 on CPT-induced apoptosis were also examined in PEDF gene knockdown HepG2 cells. Treatment with bafilomycin A1 suppressed CPT-induced decreases in Bcl-xL expression and increases in apoptosis in PEDF gene knockdown HepG2 cells. PEDF may, therefore, exert anti-apoptotic effects through inhibition of lysosomal degradation of Bcl-xL in CPT-treated HepG2 cells