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 worksare emerging to support the efficacy of probiotic strains to increasemyocardial resistance to ischemia–reperfusion injury (IRI) in polymorbidity.The question remains open whether the presence of live probioticbacteria is a prerequisite for the implementation of their cardioprotectiveeffect. This work was aimed to determine the manifestation of thecardioprotective 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 modelof left coronary artery (LCA) occlusion–reperfusion. Experimentswere performed on male Wistar rats with an improved conventionalstatus with visceral obesity, chemically induced colitis, and antibiotic-inducedgut dysbiosis, which co-provided SIRS formation against the backgroundof oral administration of live or inactivated probiotic bacteria.Infarct size in the group with a SIRS model (SIRS group) was significantlylarger than in the control group [43% (39; 44) vs. 31% (28; 35)](p < 0.05). In the SIRSgroup administered with inactivated probiotic bacteria, infarctsize did not differ from that in the SIRS group and was significantlyhigher than in the control [45% (37; 48)] (p <0.05). At the same time, infarct size in the group administeredwith live probiotics did not differ from that in the control group[32% (28; 37)]. Conclusions: (1) live and inactivated probioticstrains of Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis exertdifferent effects on rats with SIRS, (2) cardioprotective effectis only provided by live lacto- and bifidobacteria in animals withSIRS.