Probiotic strains improve high-fat diet-induced hypercholesterolemia through modulating gut microbiota in ways different from atorvastatin.

Hypercholesterolemia is a major risk factor for cardiovascular disease (CVD). Probiotics are one of the most popular dietary supplements for hypercholesterolemia, but there are questions as to whether there are differences between probiotics and cholesterol-lowering drugs like atorvastatin (ATO) both in effectiveness and in the underlying mechanisms. In this study, the hypocholesterolemia effects of 4 probiotic strains were investigated and compared with ATO, focusing on their impacts on the gut microbiota. A hypercholesterolemia model was established via high-fat diet (HFD) in golden hamsters after which ATO and the 4 probiotics were orally administered individually for 8 weeks. All probiotics were effective, but less than ATO, on body weight, serum parameters (TG, TC, LDL, INS, HbA1c) and expression of inflammatory factors (INF-α, IL-1ß, CRP), with strain JQII-5 being most significant. Besides, these effects were associated with restoration of microbiota dysbiosis induced by HFD. It was worth noting that ATO and probiotics induced different shifts of the gut microbiota in both structure and key phylotypes. Most interestingly, Allobaculum, a HFD-suppressed genus, reported to be involved in alleviating oxidative stress, was enriched by all tested probiotic strains, but not by ATO. Furthermore, Prevotella, also a HFD-suppressed genus, was uniquely reversed by JQII-5. Importantly, most of the alerted genera and reversed genera were found to be correlated with the inflammatory state and serum lipid level. Compared with ATO, the probiotic strains were less effective on body weight, hypercholesterolemia, and inflammation. However, probiotics exert additional favorable effects on the gut microbiota, making them excellent potential complements to cholesterol-lowering drugs like ATO.

Yak-Kong Soybean (Glycine max) Fermented by a Novel Pediococcus pentosaceus Inhibits the Oxidative Stress-Induced Monocyte-Endothelial Cell Adhesion.

Yak-Kong (YK), a small black soybean (Glycine max) in Korea, contained higher concentrations of antioxidants than ordinary black soybean or yellow soybean in our previous study. We prepared the fermented YK extract by using a novel lactic acid bacterium, Pediococcus pentosaceus AOA2017 (AOA2017) isolated from Eleusine coracana, and found that the antioxidant ability was enhanced after fermentation. In order to investigate the cause of the enhanced antioxidant ability in the fermented YK extract, we conducted a phenolic composition analysis. The results show that proanthocyanidin decreased and phenolic acids increased with a statistical significance after fermentation. Among the phenolic acids, p-coumaric acid was newly produced at about 11.7 mg/100 g, which did not exist before the fermentation. Further, the fermented YK extract with increased p-coumaric acid significantly inhibited the lipopolysaccharide-induced THP-1 monocyte-endothelial cell adhesion compared to the unfermented YK extract. The fermented YK extract also suppressed the protein expression levels of vascular cell adhesion molecule (VCAM)-1 in human umbilical vein endothelial cells (HUVECs). Together with the previous studies, our results suggest that the extract of YK fermented by AOA2017 has potential to be a new functional food material with its enhanced bioactive compounds which may help to prevent atherosclerosis caused by oxidative stress.