Strain-Specific Lactobacillus Probiotics Intervention in Mitigating Obesity and Metabolic Dysregulation via Gut Microbiota Modulation in a Mouse Model of High-Fat Diet.

Obesity and associated chronic diseases are major challenges to good health globally. Therapies based on probiotic modalities are rapidly gaining attention. The current study highlights the strain-specific effects of probiotics Lacticaseibacillus rhamnosus GG ATCC 53103 (LR), Lactiplantibacillus plantarum ATCC 8014 (LP), and Lactobacillus delbrueckii subsp. lactis ATCC 12315 (LD) on obesity, metabolic health, and gut microbiota in C57BL/6 mice on either a high-fat diet (23.71% fat) or standard diet (5.5% fat). Eight groups were assessed over eight weeks with or without probiotic supplementation. LR in the HFD cohort (LR-H) demonstrated the greatest efficacy, reducing weight gain by 25.1% (6.26 ± 0.61 g vs. 8.36 ± 1.02 g), visceral adipose tissue (VAT) by 11.1% (2.16 ± 0.10 g vs. 2.43 ± 0.12 g), and liver weight by 11.4% (3.03 ± 0.10 g vs. 3.42 ± 0.12 g) compared with the HFD group. Metabolic improvements included reductions in serum glucose (20.7%), triacylglycerol (TG) (23.5%), cholesterol (8.9%), low-density lipoprotein (LDL) (13.2%), and alanine transaminase (ALT) (63.4%). LR also decreased leptin and lipopolysaccharide (LPS) levels by 24.1% and 16.2%, suggesting reduced inflammation. Gut microbiota analysis revealed increased Firmicutes and beneficial genera (Lactobacillus, Allobaculum). LP and LD showed lesser effects, with weight gains of 8.04 ± 0.98 g and 7.21 ± 1.15 g, respectively. The superior efficacy of LR highlights its potential for obesity management, meriting further clinical exploration.