Effects of Prostaglandin E1 on NF-κB and ICAM-1 Expression in Preconditioning Myocardium of Rats with Ischemia Reperfusion Injury
|Keywords||Prostaglandin E1 PGE1 Ischemia-reperfusion injury (IRI) Pharmacological preconditioning (PPC) Nuclear factor -κB (NF-κB) Intercellular adhesion molecule -1 (ICAM-1) Isolated heart|
In recent years, with thrombolytic therapy after myocardial infarction, coronary artery bypass grafting, percutaneous transluminal coronary angioplasty and other cardiac interventional therapy widely carried out, in order to save the ischemic myocardium, reduced infarct size, improved clinical symptoms from to good results. However, the resulting myocardial ischemia-reperfusion injury (MIRI) an impact on results of operations and a key factor in the prognosis of patients, how to reduce ischemia-reperfusion injury (IRI) to become a serious problem. PGE1 inhibits platelet aggregation and thromboxane A2 formation, atherosclerotic plaque and immune complex formation, and can expand peripheral and coronary blood vessels. PGE1 our group had done a lot to protect the myocardium experimental study demonstrated that it can improve myocardial ischemia-reperfusion hemodynamics; effective in reducing myocardial CPK and LDH leakage, reducing myocardial ultrastructural damage; Enhanced myocardial reperfusion SOD activity, reducing production of MDA myocardial lipid peroxidation through effective ways to reduce MIRI; promote bcl-2 protein expression, inhibition of bax protein expression was significantly inhibited hypoxia reoxygenation apoptosis; improve myocardial The content within Gαq/11 promote KATP channel, reduce calcium overload; promote the expression of PKC and HSP, improve cell stress response capability to protect myocardial ischemia-reperfusion. However, PGE1 pretreatment in isolated rat myocardial ischemia-reperfusion injury in NF-κB and ICAM-1 expression mediated inflammatory damage and NF-κB and ICAM-1 link between not been reported. Therefore, this experiment by Western blot and immunohistochemistry techniques to observe the NF-κB and ICAM-1 in ischemia-reperfusion myocardial expression pattern, explore its PGE1 preconditioning on rat myocardial ischemia-reperfusion injury role for PGE1 as pharmacological preconditioning (PPC) is an effective drug in the prevention of cardiovascular disease to provide the theoretical basis for a wide range of applications. Objective: Langendorff perfused rat heart preparation device myocardial ischemia-reperfusion injury model to investigate the PGE1 pretreatment on myocardial ischemia-reperfusion injury of myocardial cell NF-κB and ICAM-1 protein expression, and further from inflammation signaling pathway reveals PGE1 on myocardial ischemia-reperfusion injury in the possible mechanism. Methods: Healthy adult SD rats, male and female, weighing 250-300g, were randomly divided into five groups of eight: normal control group, ischemia-reperfusion group and PGE1 small, medium and large dose (14μg / L , 42μg / L, 126μg / L) pretreatment groups first with normal perfusion liquid equilibrium desktop 15min, normal control group continued with normal desktop solution perfused 3h; ischemia-reperfusion group with a normal desktop perfusion after 30min stopping irrigation 30min, and then use the normal desktop perfusion 2h; PGE1 each dose (14μg / L, 42μg / L, 126μg / L) pretreatment liquid equilibrium normal desktop after 15min perfusion containing different doses for normal desktop PGE1 perfusion 30min , stopping irrigation 30min, normal desktop solution reperfusion 2h. After perfusion speed left ventricle anterior wall is divided into two parts: one part fixed preparation pathological sections, HE staining myocardial tissue morphology changes and immunohistochemical determination of NF-κB and ICAM-1 expression changes ; another part cryopreserved in liquid nitrogen to keep as Western blot, semi-quantitative detection of intracellular NF-κB expression changes. Results are applied SPSS17.0 software package for univariate analysis of variance, the data were expressed as mean ± standard deviation (x ± s) that the groups were compared using the LSD method, the test results were taken as α = 0.05 significance level. Results: 1 myocardial tissue of rats morphological changes observed under light microscope, the normal control group no abnormal morphological changes in myocardial tissue, muscle fiber integrity, dyeing uniformity, myocardial tightly packed cells, stripes clear, no vascular interstitial expansion and inflammatory cell infiltration; ischemia-reperfusion group wide range of myocardial fiber breakage, swelling, necrosis integration, uneven dyeing, myocardial cells arranged in irregular stripes disappear, dilated blood vessels and interstitial inflammatory cell infiltration; PGE1 small dose (14μg / L) a wide range of myocardial preconditioning group fiber breakage, swelling, myocardial cell disorder, some stripes disappear, interstitial vasodilation and inflammatory cell infiltration, but the degree of ischemia-reperfusion group compared with some ease; PGE1 middle dose (42μg / L) pretreatment of myocardial fiber swelling, but few rupture, interstitial vasodilator obvious, there is a small amount of inflammatory cell infiltration; PGE1 dose (126μg / L) pretreatment little myocardial fibers swelling, no fracture, no interstitial vasodilator, occasional inflammatory cell infiltration, morphology similar to the normal control group. 2 Immunohistochemical staining was measured in myocardial tissue of rats NF-κB and ICAM-1 expression (1) myocardial ischemia-reperfusion group expression of NF-κB was 47.36 ± 3.27, and the normal control group (19.99 ± 4.59) compared to its expression was significantly increased (P lt; 0.05). Compared with the ischemia-reperfusion group, PGE1 each dose pretreatment group (14μg / L, 42μg / L, 126μg / L) myocardial NF-κB expression was significantly reduced, respectively, 39.29 ± 2.63,30.49 ± 3.24,24.41 ± 4.00 (P lt; 0.05). PGE1 each dose pretreatment pairwise comparisons between groups were statistically significant (P lt; 0.05) (2) myocardial ischemia-reperfusion group of ICAM-1 expression was 50.26 ± 7.04, and the normal control group (22.98 ± 5.28) compared to its expression was significantly increased (P lt; 0.05). Compared with the ischemia-reperfusion group, PGE1 each dose pretreatment group (14μg / L, 42μg / L, 126μg / L) myocardial tissue of ICAM-1 expression was significantly reduced, respectively, 42.28 ± 4.69,34.96 ± 4.01,29.51 ± 4.82 (P lt; 0.05). PGE1 each dose pretreatment pairwise comparisons between groups were statistically significant (P lt; 0.05). 3 Western blot determination of myocardial tissue of rats NF-κB expression of NF-κB in ischemia-reperfusion group (0.842 ± 0.016) expression compared with normal control group (0.278 ± 0.015) was significantly increased (P lt; 0.05); Compared with the ischemia-reperfusion group, PGE1 each dose pretreatment group (14μg / L, 42μg / L, 126μg / L) NF-κB expression in turn decreases were 0.682 ± 0.023,0.527 ± 0.019, 0.390 ± 0.015 (P lt; 0.05). PGE1 each dose pretreatment pairwise comparisons between groups were statistically significant (P lt; 0.05). Conclusions: 1 PGE1 pretreatment improves myocardial ischemia and reperfusion in rats fiber morphological changes effectively reduce rat myocardial ischemia-reperfusion injury. 2 PGE1 may inhibit NF-κB and ICAM-1 expression in myocardial tissue to reduce PMN-mediated inflammatory response, which may be PGE1 myocardial ischemia-reperfusion injury mechanisms. 3 NF-κB by regulating the expression of ICAM-1 in myocardial ischemia-reperfusion injury play a role.