Exploring the health-promoting potential: Dietary intervention with live or inactivated Lactobacillus gasseri HM1 probiotics in obese mice

[Display omitted] •Dietary, viable, and inactivated HM1 intervention show distinct metabolic effects.•Viable HM1 improved serum triglycerides, glucose, and insulin tolerance.•HK-HM1 and SK-HM1 lessened varied inflammatory markers in colon.•HK-HM1 reduced inflammation in the colon, epididymal, and perirenal fat. This study explores the impact of dietary interventions with live or inactivated Lactobacillus gasseri HM1 probiotics on metabolic health in mice. After inducing obesity in 24 mice with a high-fat diet, they transitioned to a standard chow diet (SCD) while receiving a daily oral placebo, live HM1, heat-killed HM1 (HK-HM1), or sonication-killed HM1 (SK-HM1) for 6 weeks. Results indicate that SCD with live HM1 significantly improved triglyceride levels, glucose tolerance, and insulin sensitivity. SK-HM1 improved perirenal fat inflammation and reduced serum leptin concentration, while HK-HM1 showed improvements in inflammation in fat tissues and reduced serum IL-6, leptin, and catalase protein levels. Both HK-HM1 and SK-HM1 reduced colon IL-6, TGF-β1, and IL-1β cytokine levels, with HK-HM1 having the most significant effect. These findings underscore the potential of dietary interventions with HM1 probiotics to enhance metabolic health, revealing distinct benefits between live and inactivated forms.