Preliminary Study On The Epression Of PI3K/AKT Signaling Pathway In Sepsis Rat Cardiomyocytes

Background:Sepsis-induced cardiomyopathy(SIC)is a common complication of sepsis,which significantly increases the hospital mortality of sepsis patients and seriously affects the prognosis of patients.At present,the pathogenesis of SIC is still unclear.Studies have shown that the inflammatory factors of sepsis can inhibit the contractile function of the heart,and the PI3K/AKT signaling pathway is the central regulator of the immune system and the expression of inflammatory factors.This master’s project intends to establish a rat model of sepsis through animal experiments to understand the degeneration of myocardial cells and、the infiltration of inflammatory cells and PI3 K,AKT protein expression in sepsis rats,preliminary exploration of the expression level of PI3K/AKT signaling pathway in sepsis rat cardiomyocytes,in order to explore the possible signaling pathways related to the pathogenesis of SIC.Methods:1.SD rats(n=18)were randomly divided into three groups: sepsis group(n=6),sham operation group(n=6)and control group(n=6).Rats in the sepsis group were prepared by intraperitoneal injection of Lipopolysaccharide(LPS)method(10 mg/kg).The sham-operated group was treated with intraperitoneal injection of the same amount of normal saline,while the control group was not given any treatment.Rats in each group were kept in a dry cage for 12 h2.Observe rats’ reaction: spirit,diet,activity,and urination,and record them.3.After 12 hours of modeling,observe the degeneration of myocardial cells and the infiltration of inflammatory cells by HE staining.4.After 12 hours of modeling,myocardial tissue were detected the expression of PI3 K and AKT protein by western blot analysis.Results:1.General situation: Rats in the sepsis group generally have different degrees of drowsiness,curling,unresponsiveness,decreased activity,diarrhea,anorexia,hair erection,fever and other sepsis manifestations;rats in the sham group postoperative reactions sensitive,except there were2 anorexia;none of the control rats showed the above performance,the hair was supple,and the spirit,activity,diet,and stool were normal.2.After 12 hours of modeling,HE staining light microscope showed that the myocardial tissue of rats in the sepsis group had different degrees of inflammatory cell infiltration,myocardial cell edema,myocardial fiber arrangement disorder,myocardial fiber wave-like changes,myocardial rupture,myocardial interstitial blood vessels dilation and hyperemia,red blood cells between myocardium ooze,and focal myocardial necrosis can be seen.The myocardial fiber structure of the control group and the sham-operated group was tightly arranged,the nuclei were clear,there was no obvious inflammatory cell infiltration,and there was no edema,hyperemia,and exudation.Analysis of the myocardial histopathological scores of rats in each group showed that the myocardial histopathological score(2.53±1.17 points)of the sepsis group was significantly higher than that of the sham operation group(0.30±0.47 points)and the blank control group(0.20±0.41 points),P<0.05.3.After 12 hours of modeling,the results of Western blot detection and analysis showed that the relative net optical density of PI3K(0.67±0.12)in the myocardial tissue of rats in the sepsis group was higher than that in the control group(0.19±0.06)and the sham operation group(0.22±0.01)significantly increased,P<0.05,the difference was statistically significant;the relative net optical density value of AKT(0.47±0.08)in myocardial tissue of rats in sepsis group was higher than that in control group(0.31±0.13)and sham operation group(0.25±0.03)significantly increased,P<0.05,the difference was statistically significant.Conclusion:1.Sepsis can cause a certain degree of myocardial damage.The myocardial tissue in the sepsis group rats showed varying degrees of inflammatory cell infiltration,myocardial cell edema,myocardial fiber arrangement disorder,myocardial fiber wave-like changes,myocardial rupture,myocardial interstitial blood vessels dilation and hyperemia,red blood cells between myocardium ooze,and focal myocardial necrosis can be seen.2.The expression level of PI3 K and AKT protein in myocardial tissue of sepsis rats increased significantly.