Protective effect and mechanism of plant-derived Lactobacillus G11 on septic myocardial injury.

Background: Sepsis is currently one of the leading causes of morbidity and mortality worldwide. Myocardial injury is the most common and severe complication of sepsis. Lactic acid bacteria are a type of gram-positive bacteria found in fermented foods. Our research group previously isolated two new strains G8 and G11 from Jiangshui.

Methods: The probiotic effects of G8 and G11 strains were measured using acid and bile salt resistance tests, bacteriostasis tests, and extracellular polysaccharide (EPS) production tests. In a mouse SIMI model induced by cecal ligation and puncture (CLP), their protective effects were explored using survival rate, body weight, sepsis score, and rectal temperature. Furthermore, RNA-seq and some molecular biology methods were used to investigate G11's protective mechanism against SIMI.

Results: Initially, strain G8 and G11 from LAB were successfully isolated and found to possess multiple probiotic functions, such as cholesterol degradation, bacteria inhibition, and production of extracellular polysaccharides (EPS). Treatment with G11 increased the survival rate in CLP-injured mice. Subsequently, G11 treatment improved the rectal temperature, sepsis score, blood routine parameters, and blood biochemical parameters in CLP-injured mice. Additionally, G11 was observed to significantly alleviate cardiac dysfunction, oxidative stress, apoptosis, mitochondrial dysfunction, and inflammation in CLP-injured mice. Finally, this study also confirmed that the AMPK/ACC and SIRT1/PGC-1α signaling pathways may play a crucial role in the protective effects of G11.

Conclusion: These findings support G11 as a potential cardioprotective probiotic for alleviating SIMI in clinical practice and expanding the use of G11 in sepsis treatment.