Effect of AOB, a fermented‐grain food supplement, on oxidative stress in type 2 diabetic rats

Abstract

Reactive oxygen species (ROS) play an important role in the pathogenesis of diabetic complications. Antioxidant Biofactor (AOB) is a mixture of commercially available fermented grain foods and has strong antioxidant activity. This study investigated the effect of AOB supplementation of standard rat food on markers of oxidative stress and inflammation in Otsuka Long-Evans Tokushima Fatty (OLETF) rats with type 2 diabetes. Blood glucose, hemoglobin A1c, plasma free fatty acid, triacylglycerol and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in OLETF rats than in non-diabetic control Long-Evans Tokushima Otsuka (LETO) rats at 29 weeks. AOB (6.5% of diet) was given to rats during 29-33 weeks of diabetic phase in OLETF rats. OLETF rats with AOB supplementation showed decreased blood glucose, hemoglobin A1c, triacyglycerol, low density lipoprotein, cholesterol and PAI-1. Mitochondrial ROS production was significantly increased in heart, aorta, liver and renal artery of OLETF rats. Uncoupling protein 2 (UCP2) is known to regulate ROS production. We found aortic UCP2 protein expression increased in OLETF rats, and AOB returned UCP2 expression to normal. Aortic endothelial NO synthase (eNOS) was also increased in OLETF rats more than in LETO rats at 33 weeks. In contrast, phosphorylated vasodilator-stimulated phosphoprotein, an index of the NO-cGMP pathway, was significantly diminished. AOB increased eNOS proteins in LETO and OLETF rats. In conclusion, AOB significantly improved the NO-cGMP pathway via normalizing ROS generation in OLETF rats. The data suggest that dietary supplementation with AOB contributes to nutritional strategies for the prevention and treatment of type 2 diabetes mellitus.

Effects of Phenolic Compounds of Fermented Thai Indigenous Plants on Oxidative Stress in Streptozotocin‐Induced Diabetic Rats

“…Glucose autooxidizes in the presence of transition metal ions generating oxygen-free radicals, make the membrane vulnerable to oxidative damage [42–44]. Natural fermented products have been used to improve health as well as an alternative therapy, possibly due to their antioxidative, anti-inflammatory, antigenotoxic, free-radicals scavenging, and antilipid peroxidation activities [13, 17, 18, 45–48]. …”

“…During Lactobacillus fermentation organic acids are formed and accumulated, possibly leading to protein hydrolysis and solubilisation of antioxidant ferulic acid from cell wall plant materials [14–16]. Fermentation of grain food with Aspergillus oryzae possesses strong antioxidant and free-radicals scavenging activities [17]. Antioxidative and anti-inflammatory activities of the biologically fermented plant products can be utilized alternatively for improving health as well as treatment for patients with such diseases as HIV and cancer [18].…”

Fermented Wheat Germ Extract (Avemar) in the Treatment of Cardiac Remodeling and Metabolic Symptoms in Rats

“…Antioxidants such as N-acetylcysteine, vitamin C and E have also shown anti-diabetic effects possibly by protecting pancreatic β -cells from glucose toxicity, stimulating insulin secretion and moderately reducing blood glucose levels [41–43]. One of the consequences of elevated blood glucose concentrations is the non-enzymatic glycation of proteins such as hemoglobin A1c (HbA1c) and serum albumin [44].…”

Fermentation by Lactobacillus enhances anti-inflammatory effect of Oyaksungisan on LPS-stimulated RAW 264.7 mouse macrophage cells

“…During the process of fermentation by Lactobacillus , organic acids are amassed, proteins are hydrolyzed and antioxidant ferulic acid from plant cell wall materials are solubilized [6,7]. When the grain foods once were fermented with Aspergillus oryzae , strong antioxidant destroying free radicals were formed [8]. Those fermented plant products could contain antioxidative activities and anti-inflammatory activities, which can be used as a good and alternative method to treat patients who suffer from diseases like cancer and HIV [9].…”