Amelioration of Type 2 Diabetes Using Four Strains of Lactobacillus Probiotics: Effects on Gut Microbiota Reconstitution-Mediated Regulation of Glucose Homeostasis, Inflammation, and Oxidative Stress in Mice

This study aims to explore the preventive effects and underlying mechanisms of Lactobacillus fermentum CKCC1858 (CKCC1), L. fermentum CKCC1369 (CKCC2), Lactobacillus plantarum CKCC1312 (CKCC3), and Lactobacillus gasseri CKCC1913 (CKCC4) on high-fat diet combined with streptozotocin (HFD/STZ)-stimulated type 2 diabetes (T2D) in mice. Generally, the results indicated that most of the four probiotics reduced weight loss and liver and pancreas damage, significantly (p < 0.05) improved glucose metabolism by regulating glucagon-like peptide-1 (GLP-1), fasting glucose and insulin levels, and increasing expression of glucose transporters. Probiotics improved hyperlipemia, inflammation, and oxidative stress by reducing the secretion of blood lipids and proinflammatory cytokines, increasing antioxidant enzymes. Metagenomic results revealed that probiotics restored gut microbiota via enhancing (reducing) the relative abundance of beneficial bacteria (harmful bacteria) and altered specific metabolic pathways in T2D mice. CKCC1, CKCC3, and CKCC4 showed excellent effects compared to CKCC2. These results indicated that probiotics potentially prevented T2D, which is strain-specific.