Influence of Gender on the Size of Myocardial Infarction and Behavioral Responses in Obese Rats with Systemic Inflammatory Response under Probiotic Correction

Aim: to study myocardial resistance to ischemia-reperfusion and behavioural responses taking into account sex differences in rats in an experimental model of obesity and systemic inflammatory response syndrome (SIRS). Materials and methods : experiments were performed on male and female Sprague–Dawley (SD) rats at the age of three months with primary visceral obesity (PVO). SIRS was modelled by a single rectal injection of acetic acid, followed by intragastrical administration of the antimicrobial drugs mixture (AMP) for 3 days. The other group of rats was treated orally with a mixture of probiotic strains Lactobacillus acidophilus (LA-5) and Bifidobacterium animalis subsp. lactis (BB-12), at a CFU concentration of 10 8 per animal for 8 days after the simulation of SIRS. Behavioural tests “open field” (OFT), “elevated plus maze” (EPM), “light–dark box” (LDB) were performed alternately before the end of the experiment. At the end of the experiment, the levels of tumor necrosis factor-α, interleukin-2, leptin, lipopolysaccharide, transforming growth factor-β and brain neurotrophic factor in the blood were assessed, hemodynamic parameters and myocardial resistance to ischemia-reperfusion were studied on an isolated heart model. Results: a higher food intake per 1 g of body mass and more pronounced thrombocytosis and granulocytosis were observed in the group of female rats, as compared to males after the SIRS modelling. Female rats had higher serum levels of tumor necrosis factor-α, leptin, interleukin-2, and lipopolysaccharide than males, as well as lower levels of transforming growth factor-β. In male rats, probiotic modulation of orientation and exploratory behaviour and anxiety was observed whereas in female rats the rate of conditioned reflexes formation was corrected by probiotics. There were no significant differences in hemodynamic parameters, as well as in the size of the infarction between the studied groups. Conclusion: the data obtained indicate a significant role of sex hormones in the pathogenesis of SIRS, as well as a different response of females and males to probiotic therapy. The results generally show a higher intensity of compensatory-adaptive reactions and a greater efficiency of probiotic correction of SIRS in female rats compared to males. At the same time, the size of the infarction did not differ between females and males.