Lactiplantibacillus plantarum dfa1 reduces obesity caused by a high carbohydrate diet by modulating inflammation and gut microbiota

Abstract

Abstract Given the potential of probiotics to counteract obesity induced by high glucose diets (HGD) and the beneficial effects of high-fiber diets, this study explored the impact of Lactiplantibacillus plantarum dfa1 (Lp dfa1) in mice consuming modified diets, including a unique high-carbohydrate biscuit diet (HBD) featuring Prachuap Khiri Khan’s Pineapple Cheese Cake Biscuit for its rich fiber content. Notably, the fruit-derived soluble fiber HBD might have a synbiotic effect (the enhanced beneficial bacteria in the gut) different from HGD. in The standard mouse diet (RD) with a carbohydrate: protein: fat (C: P:F) ratio of 56:13:31 served as the base, which was then modified with either glucose to form the HGD (C: P:F at 60:25:15) or blended with the high-fiber dessert to create the HBD (C: P:F at 70:9:21). Over 12 weeks, mice were fed HGD or HBD with and without daily oral administration of Lp dfa1 at 1 × 109 CFU. This study aimed to assess the effects on obesity indicators (weight gain, lipid profiles, fat deposition), prediabetes markers (fasting glucose, insulin, oral glucose tolerance test, and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)), intestinal health (FITC-dextran assay for enterocyte injury, serum cytokines TNF-α, IL-10, and IL-6), and liver health (enzymes, weight, histology, carbohydrate and fat components, and oxidative stress). Both HGD and HBD induced similar obesity metrics, prediabetic conditions, enterocyte injury, altered serum cytokines, and liver damage. Remarkably, Lp dfa1 administration mitigated these adverse effects with an elevation in fecal short-chain fatty acids. Microbiome analysis revealed diet-induced dysbiosis, with a notable difference between HGD and HBD impacts, particularly in the Fermicutes/Bacteroides ratio and Akkermansia spp. abundance, which was significantly elevated in the HBD + Lp group. Actinomycota with a lower Proteobacteria in HBD compared with HGD group indicate the possible different impacts between the mixed sugar with fruit-derived soluble fiber versus pure glucose. Interestingly, Lp dfa1 elevated Akkermansia spp. (a well-known beneficial probiotic against obesity) only in mice with HBD but not HGD, despite an obesity attenuation by Lp dfa1 in both HGD and HBD groups, implying the different anti-obesity mechanisms. In vitro experiments revealed Lp dfa1’s supernatant reduced inflammation in Caco-2 and HepG2 cell lines, evidenced by improved transepithelial electrical resistance (TEER), expression of occludin-1 (a tight junction molecule), decreased inflammatory mediators (NF-κB, TNF-α, IL-8, IL-6, and IL-10), and elevated mucin gene. Conclusively, Lp dfa1 demonstrates a dual mechanism in preventing sugar-induced intestinal injury and supporting metabolic health: direct cellular protection and microbiome modulation. These findings highlight the additive effects of Lp dfa1 and high-fiber diets, particularly emphasizing the Pineapple Cheese Cake Biscuit-based diet’s role in enhancing gut microbiota and addressing diet-induced health issues.