Prebiotic-mediated gastroprotective potentials of three bacterial levans through NF-κB-modulation and upregulation of systemic IL-17A.

This study aimed to investigate whether the gastroprotective effects of three types of bacterial levans are correlated with their prebiotic-associated anti-inflammatory/antioxidant potentials. Three levans designated as LevAE, LevP, and LevZ were prepared from bacterial honey isolates; purified, and characterized using TLC, NMR, and FTIR. The anti-inflammatory properties of levan preparations were assessed in LPS-stimulated RAW 264.7 cell lines, while their safety and gastroprotective potentials were assessed in Wistar rats. The three levans significantly reduced ulcer number (22.29-70.05 %) and severity (31.76-80.54 %) in the ethanol-induced gastric ulcer model compared to the control (P < 0.0001/each), with the highest effect observed in LevAE and levZ (200 mg/each) (P < 0.0001). LevZ produced the highest levels of glutathione; catalase activity, and the lowest MDA levels (P = 0.0001/each). The highest anti-inflammatory activity was observed in LevAE and levZ in terms of higher inhibitory effect on IL-1ß and TNF-α production (P < 0.0001 each); COX2, PGE2, and NF-κB gene expression. The three levan preparations also proved safe with no signs of toxicity, with anti-lipidemic properties as well as promising prebiotic activity that directly correlated with their antiulcer effect. This novel study highlights the implication of prebiotic-mediated systemic immunomodulation exhibited by bacterial levans that directly correlated with their gastroprotective activity.

Lactobacillus-fermented yogurt exerts hypoglycemic, hypocholesterolemic, and anti-inflammatory activities in STZ-induced diabetic Wistar rats.

Hyperglycemia is a symptom of type 2 diabetes mellitus, a chronic metabolic disease characterized by elevated blood glucose concentrations. Antidiabetic drugs are common treatments for this metabolic disorder; however, they may have unpleasant side effects. This study hypothesized that probiotic fermented products could preserve nutritional value, maintain metabolic homeostasis, and attenuate the inflammatory response associated with diabetes while reducing side effects. Lactobacillus plantarum KU985438 and Lactobacillus rhamnosus KU985439 showed the lowest alfa-amylase enzyme (α-amylase) activity among 8 lactobacilli tested. These 2 strains were used to develop functional fermented milk products, and their antidiabetic efficacy was tested in induced diabetic Wistar rats. The treatment of diabetic rats with L. plantarum KU985438 or L. rhamnosus KU985439 fermented yogurt resulted in a considerable reduction in blood glucose concentrations (136.79% and 145.17%, respectively) and α-amylase concentrations (56.84% and 56.84%, respectively) compared with conventional treatments. Diabetes relief began after 4 days of yogurt consumption compared with drug-based treatment. Significant improvements in both liver and kidney enzyme concentrations were also observed, in addition to a significant increase in high-density lipoprotein cholesterol concentrations and improved lipid profiles. Inhibition in nuclear factor κB and an increase in Bcl-2 concentrations were also detected. Histopathological examination of both hepatic and pancreatic cells revealed the positive effects of the studied treatment compared with standard treatment. Therefore, the selected Lactobacilli, which has hypoglycemic potential, could be used to produce functional nutraceutical antidiabetic supplements.