GYY4137 protects against myocardial ischemia and reperfusion injury by attenuating oxidative stress and apoptosis in rats

Hydrogen sulfide （H2S） is a gasotransmitter that regulates cardiovascular functions. The present study aimed to determine the protective effect of slow-releasing H2S donor GYY4137 on myocardial ischemia and reperfusion （I/R） injury and to investigate the possible signaling mechanisms involved. Male Sprague-Dawley rats were treated with GYY4137 at 12.5 mg/（kg.day）, 25 mg/（kg.day） or 50 mg/（kg.day） intraperitoneally for 7 days. Then, rats were subjected to 30 minutes of left anterior descending coronary artery occlusion followed by reperfusion for 24 hours. We found that GYY4137 increased the cardiac ejection fraction and fractional shortening, reduced the ischemia area, alleviated histological injury and decreased plasma creatine kinase after myocardial I/R. Both H2S concentration in plasma and cystathionine-γ-lyase （CSE） activity in the myocardium were enhanced in the GYY4137 treated groups. GYY4137 also decreased malondialdehyde and myeloperoxidase levels in serum, attenuated superoxide anion level and suppressed phosphorylation of mitogen activated protein kinases in the myocardium after I/R. Meanwhile, GYY4137 increased the expression of Bcl-2 but decreased the expression of Bax, caspase-3 activity and apoptosis in the myocardium. The data suggest that GYY4137 protects against myocardial ischemia and reperfusion injury by attenuating oxidative stress and apoptosis.

Glycine attenuates myocardial ischemia-reperfusion injury by inhibiting myocardial apoptosis in rats

Glycine is a well-documented cytoprotective agent.However,whether it has a protective effect against myocar-dial ischemia-reperfusion injury in vivo is still unknown.By using an open-chest anesthetized rat model,we found that glycine reduced the infarct size by 21% in ischemia-reperfusion injury rats compared with that in the vehicle-treated MI/R rats.The left ventricular ejection fraction and fractional shortening were increased by 19.11% and 30.98%,respectively,in glycine-treated rats.The plasma creatine kinase levels in ischemia-reperfusion injury rats decreased following glycine treatment.Importantly,administration of glycine significantly inhibited apoptosis in post-ischemia-reperfusion myocardium,which was accompanied by suppression of phosphorylated p38 mitogen-activated protein kinase and c-Jun NH2-terminal kinase,as well as the Fas ligand.These results suggest that gly-cine attenuates myocardial ischemia-reperfusion injury in vivo by inhibiting cardiomyocytes apoptosis.

Correlation of QRS complex after percutaneous coronary intervention with myocardial ischemia reperfusion injury and apoptosis molecule contents

Objective: To study the correlation of QRS complex after percutaneous coronary intervention (PCI) with myocardial ischemia reperfusion injury and apoptosis molecule contents. Methods:Patients with non-ST-segment elevation myocardial infarction who were treated in Nanchong Central Hospital between June 2014 and August 2016 were selected and divided into the PCI group who received emergency PCI surgery and the control group who accepted selective PCI or refused emergency PCI after the medical data were retrospectively analyzed. The fQRS as well as the contents of ischemia reperfusion injury indexes and apoptosis molecules was determined after 1 week of treatment. Results: The incidence of fQRS in PCI group was significantly lower than that in control group;serum MDA, cTnI, H-FABP, sTWEAK, sFas, sTRAIL and Caspase-3 contents as well as peripheral blood Nrf-2 and HO-1 expression of PCI group were greatly lower than those of control group;serum MDA, cTnI, H-FABP, sTWEAK, sFas, sTRAIL and Caspase-3 contents as well as peripheral blood Nrf-2 and HO-1 expression of PCI group of patients with fQRS complex (+) were greatly higher than those of patients with fQRS complex (-). Conclusion: The occurrence of fQRS after PCI is closely related to myocardial ischemia reperfusion injury and apoptosis.

Acupuncture preconditioning protects against myocardial ischemia/reperfusion injury mediated apoptosis through miR-214/NCX1 activation: a hypothesis

Early reperfusion of ischemic cardiac tissue is usually the best option to improve clinical outcome of angina pectoris, especially of acute myocardial infarction. However, myocardial reperfusion may cause an abnormal increase of intracellular Ca^2+-mediated cardiomyocyte death and consequent loss of cardiac function, which is referred to myocardial ischemia/reperfusion (I/R) injury. Recently, the microRNA-214 (miR-214)/Na^+/Ca^2+ exchanger (NCX) 1 co-expression is a key factor in cellular protection against myocardial apoptosis for myocardial I/R injury. Once activated, miR-214/NCX1 axis can inhibit several Ca^2+ downstream signaling effectors that mediate cell death simultaneously. Studies have shown that acupuncture preconditioning has a protective effect on myocardial I/R injury, but its mechanism deserves further research. It has been proved that acupuncture preconditioning for ischemic myocardium successfully inhibit multiple Ca2+ handling related microRNAs that mediate cell death pathways, and miR-214 is one of its targets. In terms of clinical practice, coronary heart disease (CHD) patients benefit a lot from this intervention. However, there is barely no study correlating acupuncture preconditioning to the miR-214/NCX1 co-expression in patients with CHD. This review aims to discuss whether there is some evidence to justify a recommendation of acupuncture preconditioning in CHD patients as a non-pharmacological therapeutic method to activate the miR-214/NCX1 co-expression network model.

Long non-coding RNA-AK138945 regulates myocardial ischemia-reperfusion injury via the miR-1-GRP94 signaling pathway

Objective:Myocardial ischemia-reperfusion injury(MIRI)is one of the leading causes of death from cardiovascular disease in humans,especially in individuals exposed to cold environments.Long non-coding RNAs(lncRNAs)regulate MIRI through multiple mechanisms.This study explored the regulatory effect of lncRNA-AK138945 on myocardial ischemia-reperfusion injury and its mechanism.Methods:In vivo,8-to 12-weeks-old C57BL/6 male mice underwent ligation of the left anterior descending coronary artery for 50 minutes followed by reperfusion for 48 hours.In vitro,the primary cultured neonatal mouse ventricular cardiomyocytes(NMVCs)were treated with 100μmol/L hydrogen peroxide(H_(2)O_(2)).The knockdown of lncRNA-AK138945 was evaluated to detect cardiomyocyte apoptosis,and a glucose-regulated,endoplasmic reticulum stress-related protein 94(GRP94)inhibitor was used to detect myocardial injury.Results:We found that the expression level of lncRNA-AK138945 was reduced in MIRI mouse heart tissue and H2O2-treated cardiomyocytes.Moreover,the proportion of apoptosis in cardiomyocytes increased after lncRNA-AK138945 was silenced.The expression level of Bcl2 protein was decreased,and the expression level of Bad,Caspase 9 and Caspase 3 protein was increased.Our further study found that miR-1a-3p is a direct target of lncRNA-AK138945,after lncRNA-AK138945 was silenced in cardiomyocytes,the expression level of miR-1a-3p was increased while the expression level of its downstream protein GRP94 was decreased.Interestingly,treatment with a GRP94 inhibitor(PU-WS13)intensified H2O2-induced cardiomyocyte apoptosis.After overexpression of FOXO3,the expression levels of lncRNA-AK138945 and GRP94 were increased,while the expression levels of miR-1a-3p were decreased.Conclusion:LncRNA-AK138945 inhibits GRP94 expression by regulating miR-1a-3p,leading to cardiomyocyte apoptosis.The transcription factor Forkhead Box Protein O3(FOXO3)participates in cardiomyocyte apoptosis induced by endoplasmic reticulum stress through up-regulation of lncRNA-AK138945.

Shuxuening Injection Inhibits Apoptosis and Reduces Myocardial Ischemia-Reperfusion Injury in Rats through PI3K/AKT Pathway

Objective: To investigate the main components and potential mechanism of Shuxuening Injection(SXNI) in the treatment of myocardial ischemia-reperfusion injury(MIRI) through network pharmacology and in vivo research. Methods: The Traditional Chinese Medicine Systems Pharmacology(TCMSP) and Pharm Mapper databases were used to extract and evaluate the effective components of Ginkgo biloba leaves, the main component of SXNI. The Online Mendelian Inheritance in Man(OMIM) and Gene Cards databases were searched for disease targets and obtain the drug target and disease target intersections. The active ingredient-target network was built using Cytoscape 3.9.1 software. The STRING database, Metascape online platform, and R language were used to obtain the key targets and signaling pathways of the anti-MIRI effects of SXNI. In order to verify the therapeutic effect of different concentrations of SXNI on MIRI in rats, 60 rats were first divided into 5 groups according to random number table method: the sham operation group, the model group, SXNI low-dose(3.68 mg/kg), medium-dose(7.35 mg/kg), and high-dose(14.7 mg/kg) groups, with 12 rats in each group. Then, another 60 rats were randomly divided into 5 groups: the sham operation group, the model group, SXNI group(14.7 mg/kg), SXNI+LY294002 group,and LY294002 group, with 12 rats in each group. The drug was then administered intraperitoneally at body weight for 14 days. The main biological processes were validated using in vivo testing. Evans blue/triphenyltetrazolium chloride(TTC) double staining, hematoxylin-eosin(HE) staining, terminal deoxynucleotidyl transferase d UTP nick end labeling(TUNEL) assay, enzyme-linked immunosorbent assay(ELISA), and Western blot analysis were used to investigate the efficacy and mechanism of SXNI in MIRI rats. Results: Eleven core targets and 30 Kyoto Encyclopedia of Genes and Genomes(KEGG) pathways were selected. Among these, the phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT) pathway was closely related to SXNI treatment of MIRI. In vivo experiments showed that SXNI reduced the myocardial infarction area in the model group, improved rat heart pathological damage, and reduced the cardiomyocyte apoptosis rate(all P<0.01). After SXNI treatment, the p-PI3K/PI3K and p-AKT/AKT ratios as well as B-cell lymphoma-2(Bcl-2) protein expression in cardiomyocytes were increased, while the Bax and cleaved caspase 3 protein expression levels were decreased(all P<0.05). LY294002 partially reversed the protective effect of SXNI on MIRI. Conclusion: SXNI protects against MIRI by activating the PI3K/AKT signaling pathway.

Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis

β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.

Effects of Ethyl Pyruvate on Myocardial Apoptosis and Expression of Bcl-2 and Bax Proteins after Ischemia-reperfusion in Rats

In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion （I/R） in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendorff model. Twenty-four rats were randomly divided into 3 groups （n=8 in each group）： control group was perfused for 120 min. In the I/R group, after 30 min stabilization the injury was induced by 30 min global ischemia followed by 60 min reperfusion. Ethyl pyruvate （EP） group was set up with the same protocol as I/R group except that it was supplied with 2 mmol/L EP 15 rain before ischemia and throughout reperfusion. Myocardial malonaldehyde （MDA） content was measured. Myocardial apoptotic index （AI） was tested by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling （TUNEL） method. The expression of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in cardiac myocytes was detected by immunohistochemistry. As compared with control group, the content of MDA, myocardial AI and the expression of Bcl-2, Bax proteins were increased significantly in I/R group, but the content of MDA, myocardial AI and the expression of Bax protein were decreased obviously and the expression of Bcl-2 protein was up-regulated in EP group （P〈0.05）. These results demonstrate that EP could inhibit apoptosis of cardiac myocytes possibly via alleviating oxidative stress, up-regulating Bcl-2 and down-regulating Bax proteins.

Buxu Tongyu Granule Alleviates Myocardial Ischemia by Activating Vascular Smooth Muscle Cell Soluble Guanylate Cyclase to Inhibit Abnormal Vasomotion

Myocardial ischemia is a serious threat to human health,and vascular dysfunction is its main cause.Buxu Tongyu(BXTY)Granule is an effective traditional Chinese medicine(TCM)for treating myocardial ischemia.However,the underlying mechanism of BXTY is still unclear.In this study,we demonstrate that BXTY ameliorates myocardial ischemia by activating the soluble guanylate cyclase(sGC)-30,50-cyclic guanosine monophosphate(cGMP)-protein kinase G(PKG)signaling pathway in vascular smooth muscle cells(VSMCs)to dilate the arteries.BXTY was given by gavage for ten consecutive days before establishing an animal model of acute myocardial ischemia in mice via the intraperitoneal injection of pituitrin.The results showed that BXTY alleviated the symptoms of myocardial ischemia induced by pituitrin in mice,including electrocardiogram abnormalities and changes in plasma enzymes.In addition,BXTY dilated pre-constricted blood vessels and inhibited the vasoconstriction of the superior mesenteric artery in a dose-dependent but endothelial-independent manner.These effects were eliminated by preincubating vascular rings with the sGC inhibitors NS 2028 or ODQ,or with the PKG inhibitor KT 5823.Moreover,BXTY increased the protein expression of sGC-b1 and the intracellular second messenger cGMP level in mouse aortic vascular smooth muscle cells(MOVAs).NS 2028 or ODQ reversed these effects of BXTY.The expression level of the cGMP downstream effector protein PKG-1 increased after treating MOVAs with BXTY.NS 2028,ODQ,or KT 5823 also reversed this effect of BXTY.In conclusion,BXTY can improve the symptoms of acute myocardial ischemia in mice,and activating the sGC-cGMP-PKG pathway in VSMCs to induce vasodilation is its key pharmacodynamic mechanism.

Inhibition of SLC26A4 regulated by electroacupuncture suppresses the progression of myocardial ischemia-reperfusion injury

Introduction:Myocardial ischemia-reperfusion(IR)injury has received widespread attention due to its damaging effects.Electroacupuncture(EA)pretreatment has preventive effects on myocardial IR injury.SLC26A4 is a Na+independent anion reverse transporter and has not been reported in myocardial IR injury.Objectives:Tofind potential genes that may be regulated by EA and explore the role of this gene in myocardial IR injury.Methods:RNA sequencing and bioinformatics analysis were performed to obtain the differentially expressed genes in the myocardial tissue of IR rats with EA pretreatment.Myocardial infarction size was detected by TTC staining.Serum CK,creatinine kinase-myocardial band,Cardiac troponin I,and lactate dehydrogenase levels were determined by ELISA.The effect of SLC26A4 on cardiomyocyte apoptosis was explored by TUNEL staining and western blotting.The effects of SLC26A4 on inflammation were determined by HE staining,ELISA,and real-time PCR.The effect of SLC26A4 on the NF-κB pathway was determined by western blotting.Results:SLC26A4 was up-regulated in IR rats but downregulated in IR rats with EA pretreatment.Compared with IR rats,those with SLC26A4 knockdown exhibited improved cardiac function according to decreased myocardial infarction size,reduced serum LDH/CK/CK-MB/cTnI levels,and elevated left ventricular ejection fraction and fractional shortening.SLC26A4 silencing inhibited myocardial inflammation,cell apoptosis,phosphorylation,and nuclear translocation of NF-κB p65.Conclusion:SLC26A4 exhibited promoting effects on myocardial IR injury,while the SLC26A4 knockdown had an inhibitory effect on the NF-κB pathway.These results further unveil the role of SLC26A4 in IR injury.

Integrated network pharmacology and metabolomics to explore the mechanisms of Shenzao dripping pill against chronic myocardial ischemia

Background:Shenzao dripping pill(SZDP)is empirically prescribed for treating cardiac diseases.Nevertheless,there is a lack of comprehensive knowledge regarding the underlying mechanisms contributing to its therapeutic effects.The objective of this study is to investigate the underlying mechanism of SZDP against chronic myocardial ischemia(CMI)in a rat model.Methods:In this study,we utilized electrocardiographic and echocardiographic detection along with pathological tissue analysis to evaluate the efficacy of SZDP.The integration of network pharmacology and metabolomics was conducted to investigate the mechanisms.Molecular docking and molecular dynamics simulations were used to validate the binding energy between the compounds of SZDP and the associated targets.Results:The results showed that SZDP was able to improve T wave voltage,reverse CMI abnormalities in ejection fraction and fractional shortening,and restore histopathological heart damage.Metabolomics results indicated that disturbances of metabolic profile in CMI rats were partly corrected after SZDP administration,mainly affecting purine metabolism.13-Docosenamide may be the potential metabolic biomarker of the therapeutic application of SZDP for CMI.Integrating network pharmacology and metabolomics,thiopurine S-methyltransferase(TPMT),xanthine dehydrogenase/oxidase(XDH),bifunctional purine biosynthesis protein ATIC(ATIC),and cytochrome p4501A1(CYP1A1)were identified as possible targets of SZDP to exert therapeutic effects by enhancing the metabolic levels of L-Tryptophan,Deoxyribose 1-phosphate and Phosphoribosyl formamidocarboxamide.Conclusion:SZDP has a therapeutic effect on CMI by regulating metabolite levels,acting on the targets of TMPT,XDH,ATIC,and CYP1A1,and reducing cardiomyocyte injury and myocardial fibrosis.

Therapeutic Effects and Potential Mechanisms of Glyasperin A against Myocardial Ischemia Based on Network Pharmacology and Molecular Docking

[Objectives]To explore the therapeutic effects and potential mechanisms of Glyasperin A(GAA)on myocardial ischemia(MI)based on network pharmacology and molecular docking.[Methods]The molecular structure of GAA was downloaded from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),and all targets of GAA were predicted by converting 3D model molecules into SMILES online tool and Swiss target prediction.Genecards database and DisGeNET database were used to find the targets related to MI,and then Venny 2.1.0 was used to generate the corresponding Wayne diagram,and then Cytoscape 3.9.1 software was used to construct the protein-protein interaction(PPI)network.With the help of DAVID database and Microbiology,the selected core targets were enriched and analyzed by gene ontology(GO),biological process(BP),and Kyoto Encyclopedia of Genes and Genomes(KEGG),and then the molecular docking between GAA and core targets was verified by AutoDock and Pymol software.[Results]A total of 1883 MI targets were screened,and in the protein-protein interaction network,AKT1,PTGS2,PPARG,ESR1,GSK3B were the proteins with higher values.Gene ontology and KEEG enrichment analysis showed that the biological processes involved mainly included inflammatory response,negative regulation of gene expression,and response to exogenous stimuli.Signaling pathways mainly include IL-17 signaling pathway,HIF-1 signaling pathway,and so on.The results of molecular docking showed that the binding energy of GAA and core protein was less than-5 Kcal/mol in four groups.These indicated that GAA with good binding had a certain therapeutic effect on myocardial ischemia.[Conclusions]Based on the systematic network pharmacology method,this study predicts the basic pharmacological effects and potential mechanisms of GAA in the treatment of MI,and reveals that GAA may treat MI through multiple targets and signaling pathways.It is expected to provide a basis for further study of its pharmacological mechanisms.

YiQiFuMai powder injection attenuates ischemia/reperfusion-induced myocardial apoptosis through AMPK activation

The YiQiFuMai powder injection （ YQFM）, a Traditional Chinese Medicine （TCM） prescription re-de- veloped based on the well-known TCM formula Sheng-maisan, showed a wide range of pharmacological activities in cardiovascular diseases in clinic. However, its role in protection against myocardial ischemia/reperfusion （MI/R） injury has not been elucidated. The present study not only evaluated the eardioprotective effect of YQFM from MI/ R injury but also investigated the potential molecular mechanisms in vivo and in vitro. The mouse model of MI/R injury was induced by a transient vessel occlusion for 30 rain and reperfusion for 24 h. The myocardium infarct size, production of lactate dehydrogenase （LDH）, creatine kinase （CK）, TUNEL staining and easpase-3 activity were measured. AMPKeα and phospho-AMPKα was analyzed by Western blot. We further verified the protective effect and potential molecular mechanisms of YQFM in an in vitro model of simulated ischemia and reperfusion （ SI/ R） in H9c2 cardiomyocytes. Cell viability was determined, and cell apoptosis were measured by Hoechst 33342 staining and Flow cytometry. Mitochondrial membrane potential （△ψFm） was measured, and ATP content was quantified by biolumineseent assay. Expression of apoptosis-related proteins including Caspase-3, Bcl-2, Bax, AMPKα and phospho-AMPKα was analyzed by Western blot. AMPKoL siRNA transfection was also applied to the mechanism elucidation. YQFM significantly reduced myocardium infarct size and the production of LDH, CK in se- rum, and also produced a significant decrease of apoptotic index which was confirmed by TUNEL staining and the changes of caspase-3 activity. In addition, pretreatment with YQFM markedly improved cell viability and decreased LDH release. Moreover, YQFM inhibited H9c2 apoptosis, blocked the expression of easpase-3 and modulated Bcl- 2 and Bax proteins, leading to an increased mitochondrial membrane potential and cellular ATP content. Mechanis- tically, YQFM activated AMPK signaling pathways while pretreatment with AMPK inhibitor compound C and appli- cation of transfection with AMPKα siRNA attenuated the anti-apoptotie effect of YQFM. Our results indicated that YQFM could provide significant cardioproteetion against MI/R injury, and potential mechanisms might to suppres- sion of cardiomyocytes apoptosis at least in part through activating the AMPK signaling pathways.

Contribution of Myocyte Apoptosis to Myocardial Injury in an in Vivo Rabbit Preparation of Ischemia-Reperfusion

Objective: Exposure of the heart to repeated, brief episodes of coronary occlusion/reperfusion prevents lethal myocyte injury. Necrosis and apoptosis, two seemingly distinct mechanisms of cell death caused by ischemia could contribute independently to progressive loss of myocardium. Studies suggest that ischemic conditioning (IC) lessens myocyte injury by decreasing apoptosis. The goal of this study was to examine cell death in rabbit hearts subject to ischemia-reperfusion injury without (nIC) or with pretreatment by IC. Methods: In the control study, anesthetized, male rabbits (n = 4/group) underwent 30-min regional coronary occlusion (CO) and either 3, 6 or 24h reperfusion (REP). In the IC study, rabbits were pretreated by IC (2 cycles of 5-min CO and 10-min REP) before 30-min CO and subsequent REP. Additional groups were evaluated with 60, or 120-min CO followed by up to 96 h REP. Agarose electrophoresis was used to detect DNA laddering and poly (ADP-ribose) polymerase (PARP;chromatin bound nuclear DNA repair enzyme) was assessed in myocardial biopsies. Results: Genomic DNA from nIC and IC hearts showed no oligonucleosomal fragmentation. In addition, we did not detect any cleavage of PARP;however, myocardial PARP levels decreased when CO and REP durations were prolonged. Conclusion:Absence of genomic DNA fragmentation or PARP cleavage in an in vivo preparation of ischemia-reperfusion injury does not support the view that apoptosis contributes markedly to post-ischemic tissue necrosis.

Pinacidil reduces neuronal apoptosis following cerebral ischemia-reperfusion in rats through both mitochondrial and death-receptor signal pathways

Objective To investigate effect of pinacidil, an ATP sensitive potassium channel （KATP） opener, on the neuronal apoptosis and its signaling transduction mechanism following focal cerebral ischemia-reperfusion in rats. Methods One hundred male Wistar rats were randomly divided into four groups： A, sham-operated group; B, ischemia-reperfusion group; C, KATe opener treatment group; and D, KATe opener and blocker treatment group. The middle cerebral artery occlusion （MCAO） model was established by using the intraluminal suture occlusion method, neuronal apoptosis was determined by TUNEL staining, and expressions of caspase-8, caspase-9 and caspase-3 mRNA were detected by in situ hybridization. Results （1） The numbers of apoptotic neurons at 12 h, 24 h, 48 h, and 72 h were significantly less in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there was no difference between groups B and D at all time points （P 〉 0.05）. （2） The expressions of caspase-3 mRNA and caspase-8 mRNA at all times and the expressions of caspase-9 mRNA at 12 h, 24 h, 48 h, 72 h were significantly lower in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there were no differences between groups B and D at all time points （P 〉 0.05）. Conclusions KATP opener can significantly decrease the neuronal apoptosis and the expressions of caspase-3, caspase-8 and caspase-9 mRNAs following cerebral ischemiareperfusion. The neuronal apoptosis may be decreased by the inhibition of both mitochondrial and death-receptor signal pathways.

Fructose 1,6-diphosphate alleviates myocardial ischemia reperfusion injury in rats through JAK2/STAT3 pathway

Objective: To study the effect of fructose 1,6-diphosphate(FDP) on myocardial ischemia reperfusion injury in rats and its molecular mechanism.Methods: Male SPF SD rats were selected as experimental animals and randomly divided into four groups.Sham group received sham operation, I/R group were made into myocardial ischemia reperfusion injury models, FDP group were made into myocardial ischemia reperfusion injury models and then were given FDP intervention, and FDP+AG490 group were made into myocardial ischemia reperfusion injury models and then were given FDP and JAK2 inhibitor AG490 intervention.Results: CK, CK-MB, c Tn I and LDH contents in serum as well as Bax and Caspase-3 protein expression in myocardial tissue of I/R group were significantly higher than those of Sham group whereas Bcl-2, p-JAK2 and p-STAT3 protein expression in myocardial tissues were significantly lower than those of Sham group; CK, CK-MB, c Tn I and LDH contents in serum as well as Bax and Caspase-3 protein expression in myocardial tissue of FDP group were significantly lower than those of I/R group whereas Bcl-2, p-JAK2 and p-STAT3 protein expression in myocardial tissue were significantly higher than those of I/R group; CK, CK-MB, c Tn I and LDH contents in serum as well as Bax and Caspase-3 protein expression in myocardial tissue of FDP+AG490 group were significantly higher than those of FDP group whereas Bcl-2 protein expression in myocardial tissue was significantly lower than that of FDP group.Conclusion: FDP could reduce the myocardial ischemia reperfusion injury in rats by activating the JAK2/STAT3 pathway.

N-acetylcysteine attenuates ischemia/reperfusion-induced cardiocyte apoptosis in diabetic rats

Objective：To study the effects of N-acetylcysteine （NAC） on ischemia/ reperfusion （I/R）-induced myocyte apoptosis in diabetic rats. Methods：The I/R heart model was made by ligation of the left anterior descending coronary artery （LAD） close to its origin. The LAD was occluded for 30 min followed by removal of ligation to allow subsequent reperfusion for 3 h. 72 rats were randomly divided into two groups , non-diabetic group （C, n = 36） and diabetic group ,（D, n = 36）. The animals in C group were randomly reassigned into sham-operated group （CS, n = 12） , I/R group （C I/R, n = 12） and treated with NAC group （CN, n = 12）. The rats in D group were also reassigned to sham-operated group （DS, n = 12） , I/R group （DI/R, n = 12） and treated with NAC group （DN, n = 12）. Malondialdehyde （MDA） and creatine kinase isoenzyme-MB （CK-MB） were measured. Infarct size（IS/AAR%）, the apoptosis index（AI） by TUNEL staining, the number of the cells positive for Caspase-3 and positive expression index （PEI） were calculated. Results：After I/R, the IS/AAR%, CK-MB, MDA, AI and Caspase-3 PEI were higher in diabetic group than those in non-diabetic group. Treatment with NAC decreased the above parameters in both non-diabetic and diabetic rats, but the parameters in diabetic rats were higher than those in non-diabetic rats. Conclusion：Diabetic rat hearts are more susceptible to I/R-induced myocardial necrosis and myocyte apoptosis. NAC can decrease the infarct size and attenuate cardiomyocyte apoptosis in both non-diabetic and diabetic rats, but the therapeutic effects are less effective in diabetic rats than those in non-diabetic rats.

Effect of adrenomedullin on neuron apoptosis, infarction volume and expression of Egr-1 mRNA after focal ischemia-reperfusion in rats

Objective To observe the influence of adrenomedullin （ADM） on neuron apoptosis, infarction volume of brain, and the expression of early growth response 1 （Egr-1） mRNA in ischemia-reperfusion rats. Methods The arteria cerebri media was tied for 2 h to construct the ischemia model. Infarction volume was detected by triphenltetrazolium chloride （T＇I＇C） staining, neuronal apoptosis and necrosis was detected with terminal deoxynucleotidyl transferase nick labeling （TUNEL） method, and the Egr-1 mRNA expression was examined by in situ hybridization （ISH）. Results Infarction volume after ischemia-reperfusion is （269 ± 20） mm^3. Infarction volume after injection of ADM through different ways are femoral vein （239 ± 17） mm^3 （decreased by 11.2%）, arteria carotis （214 ± 14） mm^3 （by 20.4%） and lateral cerebral ventricle （209 ± 13） mm^3 （by 22.3%）, respectively. The results indicate that injecting ADM through arteria carotis and lateral cerebral ventricle is much more effective than it through femoral vein （P 〈 0.05）. The TUNEL-positive cells in cerebral cortex or hippocampus are few in the sham operation group, but much more in the ischemia-reperfusion group. After being supplied with ADM, especially through arteria carotis interna or lateral cerebral ventricle way, the TUNEL-positive cells decreased obviously. Expression of Egr- 1 mRNA was low in the cerebral cortex of the sham operation group rats, enhanced in the ischemia and reperfusion group rats, and enhanced markedly after treatment with ADM, especially through arteria carotis interna or lateral cerebral ventricle way （P 〈 0.01）. Conclusion Injection of ADM through different ways could alleviate neural dysfunction, decrease neuron apoptosis and brain infarction volume, and increase the expression of Egr- 1 mRNA.

Protective Effects of Zingiberis and Acniti Praeparatae Decoction on Myocardial IschemiaReperfusion Injury in Rats

This study aimed to investigate the protective effects of zin-giberis and acniti praeparatae decoction on oxidative stress injury induced by my-ocardial ischemia reperfusion in rats. [Method] Myocardial ischemia-reperfusion was performed by ligation of the left anterior descending coronary artery for 30 min, fol-lowed by reperfusion for 60 min. The effects of zingiberis and acniti praeparatae decoction on ECG ST segment, myocardial infarction percentage, malondialdehyde （MDA） content in the serum, superoxide dismutase （SOD） activity and other indica-tors were observed. [Result] Zingiberis and acniti praeparatae decoction could effec-tively inhibit ECG ST segment elevation caused by myocardial ischemia-reperfusion injuries, reduce the percentage of myocardial infarction, decline the content of MDA in the serum, and increase the activity of SOD. [Conclusion] Zingiberis and acniti praeparatae decoction exhibits protective effects on oxidative injuries caused by my-ocardial ischemia-reperfusion injuries in rats, which may be involved in reducing the formation of myocardial free radicals and enhancing antioxidant capacity of my-ocardium.