CHEN Haili,GONG Jiahong,LI Xuqing, et al. Effects of limb ischemic preconditioning / postconditioning on myocardial IL-6 and cardiac function in septic mice[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2022, 52(6): 453-458.
Abstract：Objective: To investigate the effects of limb ischemic preconditioning/postconditioning on myocarditis and cardiac function in sepsis mice. Methods: Sepsis mouse model was induced by intraperitoneal injection of lipopolysaccharide (LPS) 6 mg/kg. Sepsis mice were subjected to single and bilateral leg ischemic preconditioning or post adaptation intervention, or combined with ischemic preconditioning and post adaptation intervention. Proinflammatory factor interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor (TNF-α), Apelin and Atrogin-1 mRNA expression were detected by qRT-PCR. The cardiac functions of mice,including systolic function index ejection fraction (EF), transient shortening rate (FS) and diastolic function index E/A ratio, were measured by small animal ultrasound. Results: Both preconditioning and postconditioning of unilateral leg ischemia could reduce the expression of IL-6 mRNA in myocardium of septic mice (P<0.05).The combination of preconditioning and postconditioning decreased the expression of IL-6 more than ischemic preconditioning/postconditioning alone (P<0.05), but compared with LPS group, the superposition of preconditioning at an interval of 2 h further increased the expression of IL-6 (P<0.05). LPS increased IL-1β,TNF-α and atrophic gene Atrogin-1 but decreased apelin gene, while ischemic preconditioning could enhance cardiac function and reduce IL-1 β and TNF-α in septic mice, but did not change the expression of Atrogin-1 and Apelin (P>0.05). Conclusion: Ischemic preconditioning and postconditioning can effectively alleviate the high expression of IL-6 mRNA in myocardium induced by LPS, but postconditioning has no cumulative effect. IL-6 may be an important molecule involved in ischemic preconditioning to improve cardiac function in septic mice.
