Large intestinal microbial composition and serum levels of certain pro-inflammatory molecules in patients with myocardial infarction in a long-term period

Aim: to evaluate large intestinal microbial composition and serum levels of certain pro-inflammatory molecules in patients with myocardial infarction (MI) in a long-term period. Materials and Methods: 101 patients were examined; a Group 1 included 51 MI patients with type 1 ST segment elevation, and 50 patients who did not have cardiovascular disease were enrolled in a Group 2. Acute and long-term levels of interleukin (IL) 6, IL1β, IL18, C-reactive protein (CRP), tumor necrosis factor alpha (TNFα), monocyte chemotactic protein-1 (MCP-1), and fatty acid binding protein (FABP) were determined in serum and supernatants. The first stool sample collected since MI onset was tested for dysbiosis with a follow-up testing in 207 [158; 214] days. Results: as for levels of all the studied signaling molecules, acute MI patients significantly differed from their healthy peers. In a long-term period, regardless of the remaining significant difference, IL6, IL1β, IL18, MCP-1 and TNFα levels were substantially lower than in controls. Absence of clinical manifestations of dysbiosis and presence of almost normal levels of bifido-, lactobacilli and enterococci were associated with broader spectrum and an increase (often a significant one) in a number of facultative opportunistic pathogenic bacteria. A proportion of patients with a normal level of bifidobacteria and lactobacilli decreased to 44% and 72%, respectively (p=0.001 and p=0.03), with time. A proportion of typical and hemolytic E. coli, as well as enterococci, increased significantly (44%, 84%, 100%; p=0.01, p=0.03 and p=0.00, respectively). Conclusion: regular changes in serum levels of proinflammatory molecules were reported in a long-term period of MI. In the first six months after the acute event, microbial landscape associated with cardiotropic therapy is characterized by increased proportion of opportunistic pathogenic bacteria. Mean number of microorganisms is not informative for a comparative analysis of small groups, and tolerant associations between microbiota state and a course of a post-infarction period can't be detected. KEYWORDS: ST segment elevation myocardial infarction, large intestinal dysbiosis, interleukins, long-term period. FOR CITATION: Stepanov M.S., Karpunina N.S., Spasenkov G.N. Large intestinal microbial composition and serum levels of certain pro- inflammatory molecules in patients with myocardial infarction in a long-term period. Russian Medical Inquiry. 2025;9(5):275–280 (in Russ.). DOI: 10.32364/2587-6821-2025-9-5-3