Effects Of Hydrogen Sulfide On Myocardial Fibrosis Induced By Isoproterenolin Rats And Its Mechanism

Objective: This study takes the rats with myocardial fibrosis that induced by the intraperitoneal injection of isoproterenol(ISO)for 7 days as the research object.Then sodium hydrosulfide(Na HS),as hydrogen sulfide(H2S)honor,was used to treat these rats,aiming to observe the effect of H2 S on myocardial fibrosis in the rats and explore its possible mechanism.Methods: Forty-four SD rats were randomly divided into Control group(n = 10 each),H2 S group(n = 10),ISO group(n = 12),and H2 S + ISO group(n = 12).Rats in ISO group and H2 S + ISO group were given intraperitoneal injection of ISO for 7 days at a dose of 5 mg / kg/d(dissolved in 1 ml normal saline,freshly prepared before use),while rats in Control group and H2 S group was intraperitoneally injected the same dose of saline.After 24 hours,rats in H2 S + ISO group and H2 S group were accepted intraperitoneal injection of Na HS(56 umol / kg / d,dissolved in 1 ml normal saline,freshly prepared before use).Rats in Control group and ISO group were injected the same volume of saline.After 8 weeks,Left ventricular posterior wall thickness(LVPWs),left ventricular end diastolic diameter(LVd),left ventricular end systolic diameter(LVs)and left ventricular short axis shortening(FS)were measured by echocardiography.Allthe datas suggested the experimental model was successfully established.Then the body weight of each rat(BW)was weighed and the rats were sacrificed.The heart of the rats was taken out and the heart weight(HW)was measured.The heart weight index(HW / BW)was calculated.Western blotting was used to detect Ca MKII?,NF-?B,TIMP1,TIMP3,MMP12 and MMP24 protein.The myocardial collagen deposition was observed by Masson staining and transmission electron microscopy.RT-q PCR was used to detect miR-1 ?miR-150 andmiR-214.Results: 1.Compared with the Control group,the HW and HW / BW values of the ISO group increased significantly(P <0.01),and the BW in ISO group increased(P >0.05).Compared with ISO group,the HW and HW / BW values of H2 S + ISO group were significantly decreased(P <0.01),and the BW value of H2 S + ISO group decreased(P >0.05).2.Compared with the Control group,LVs?LVd and LVPWs values in the ISO group increased significantly(P <0.01).While compared with the ISO group,LVPWs in H2 S + ISO group trend decreased(P >0.05).The FS value of ISO group was lower than that of Control group and H2 S + ISO group(P <0.01),FS value of H2 S + ISO group was slightly less than Control group.3.Masson staining showed that myocardial collagen deposition in ISO group was significantly higher than that in Control group.However,compared with ISO group,collagen deposition in H2 S + ISO group was significantly decreased.4.The results of transmission electron microscopy showed that the myocardium fibers and myocardial mitochondria in ISO group appearededema,disorder and focal necrosis.While H2 S could reduce myocardial fibrosis and alleviate the edema,disorder and focal necrosis.5.The expression of Ca MKII?,NF-?B and TIMP1,TIMP3 in the ISO group were significantly higher than that in the Control group(p <0.01),while the expression of MMP12 and MMP24 were significantly lower than that in the Control group(p <0.01).Compared with ISO group,the expression of Ca MKII?,NF-?B,TIMP1,TIMP3 in H2 S + ISO group were down-regulated(p <0.01),while the expression of MMP12 and MMP24 were up-regulated(p <0.01).6.The results of real-time quantitative PCR analysis showed that the expression level of miR-1 and miR-150 in ISO group were obviously elevated than control group(p ? 0.05),miR-214reduced(p<0.05).However,compared with ISO group,the expression level of miR-1 and miR-150 were obviously reduced(p?0.05),miR-214 elevated(p>0.05)in H2 S + ISO group.Conclusion: H2 S can improve the myocardial fibrosis induced by isoproterenol in rats.The mechanism may be related to the down-regulation of Ca MKII??NF-?B and the down-regulation of miR-1 and miR-150 protein expression.