082 | Supplementation with Lactobacillus fermentum reversed fiber atrophy in a myopathy model by modulating IL-6, TNFα, and hsp60 levels, thereby enhancing muscle regeneration

Martina Sausa¹, Letizia Paladino², Federica Scalia³, Francesco Paolo Zummo¹, Giuseppe Vergilio¹, Francesca Rappa¹, Francesco Cappello¹, Melania Ionelia Gratie¹, Patrizia Proia⁴, Valentina Di Felice¹, Antonella Marino Gammazza,⁵, Filippo Macaluso¹, Rosario Barone¹ | ¹Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo; ²Department of Theoretical and Applied Sciences, eCampus University, Novedrate [CO]; ³Department of Medicine and Surgery, Kore University of Enna; ⁴Department of Psychology, Educational Science and Human Movement, University of Palermo; ⁵Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Italy.

Recent studies support the existence of a gut-muscle axis, suggesting that modulation of the gut microbiota may influence skeletal muscle homeostasis under stress conditions [1-3]. Moreover, the chaperonin Hsp60 appears to be directly involved in maintaining skeletal muscle biogenesis and homeostasis [2]. In this study the effects of Lactobacillus fermentum (L. fermentum) supplementation in a mouse model of skeletal muscle atrophy induced by chronic ethanol (EtOH) intake was evaluated, focusing on inflammatory responses and oxidative stress biomarkers. Sixty 12-month-onld female Balb/c mice were divided randomly in three groups (n=20/group): [1] an EtOH group receiving EtOH daily for 8 and 12 weeks to induce systemic oxidative stress and inflammation; [2] an EtOH plus Probiotic (EtOH+P) group receiving both ethanol and L. fermentum supplementation for same durations; and [3] a control (Ctrl) group receiving a standard diet [4]. Exposure to EtOH induced marked muscle fiber atrophy, which mainly effected oxidative fibers, and was associated with increased expression of inflammatory mediators and stress-related proteins. The obtained results showed that supplementation with L. fermentum significantly mitigated muscle atrophy in type I and IIa fibers and reduced the expression of IL-6, TNFα, and Hsp60, indicating a protective effect against inflammation and oxidative stress. Moreover, probiotic treatment increased MyoD expression in satellite cells, suggesting an improvement in regenerative potential, without histological evidence of fibrosis. Overall, these results show that L. fermentum mitigates alcohol-induced skeletal muscle damage by modulating inflammation and oxidative stress while promoting muscle regeneration, suggesting its potential as an adjuvant strategy in experimental models of stress-related muscle degeneration.