The Impact of Live and Inactivated Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis Probiotic Strains on Myocardial Infarct Size in Rats with Systemic Inflammatory Response Syndrome.

Within the concept of a gut–heart microbiome axis, new works are emerging to support the efficacy of probiotic strains to increase myocardial resistance to ischemia–reperfusion injury (IRI) in polymorbidity. The question remains open whether the presence of live probiotic bacteria is a prerequisite for the implementation of their cardioprotective effect. This work was aimed to determine the manifestation of the cardioprotective effect of live and pasteurized Lactobacillus acidophilus (LA-5) and Bifidobacterium animalis subsp. lactis (BB-12) probiotic strains in rats with systemic inflammatory response syndrome (SIRS). Myocardial resistance to IRI was assessed using an in vivo model of left coronary artery (LCA) occlusion–reperfusion. Experiments were performed on male Wistar rats with an improved conventional status with visceral obesity, chemically induced colitis, and antibiotic-induced gut dysbiosis, which co-provided SIRS formation against the background of oral administration of live or inactivated probiotic bacteria. Infarct size in the group with a SIRS model (SIRS group) was significantly larger than in the control group [43% (39; 44) vs. 31% (28; 35)] (p < 0.05). In the SIRS group administered with inactivated probiotic bacteria, infarct size did not differ from that in the SIRS group and was significantly higher than in the control [45% (37; 48)] (p < 0.05). At the same time, infarct size in the group administered with live probiotics did not differ from that in the control group [32% (28; 37)]. Conclusions: (1) live and inactivated probiotic strains of Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis exert different effects on rats with SIRS, (2) cardioprotective effect is only provided by live lacto- and bifidobacteria in animals with SIRS. [ABSTRACT FROM AUTHOR]