Atorvastatin Alleviates Myocardial Ischemia-Reperfusion Injury via miR-26a-5p/FOXO1

Purpose: Ischemia-reperfusion (I/R) injury exacerbates myocardial cell death (including apoptosis and necrosis), leading to complications such as arrhythmias, myocardial stenosis, microvascular obstruction and heart failure, and it is particularly important to seek new strategies to mitigate reperfusion injury. In this paper, we will investigate whether atorvastatin can alleviate myocardial ischemia-reperfusion injury and verify its molecular mechanism. Methods: We successfully constructed a hypoxia-reperfusion (H/R) H9c2 cell model and transfected miR-26a-5p mimic, miR-26a-5p inhibitor and its negative control NC-mimic or NC-inhibitor into H9c2 cells using a transfection kit. The expression of miR-26a-5p and FOXO1 were detected by RT-qPCR assay, the expression of related proteins by Western blot assay, the cell viability of H9c2 cells by CCK-8 assay, the apoptosis rate of H9c2 cells by flow cytometry, the CK and LDH activity in cells by CK and LDH assay kits. The targeting relationship between miR-26a-5p and FOXO1 was verified by dual luciferase reporter gene assay. Results: MiR-26a-5p expression was decreased in H/R-induced cells and FOXO1 expression was increased in H/R-induced cells. Atorvastatin alleviated H/R injury in cardiomyocytes and was most effective at a concentration of 1 μM. Atorvastatin alleviated H/R injury in cardiomyocytes by upregulating miR-26a-5p expression, miR-26a-5p and FOXO1 were negatively regulated by targeting. Conclusion: Atorvastatin can alleviate H/R injury in cardiomyocytes by regulating miR-26a-5p/FOXO1.

Network-pharmacology-based research on protective effects and underlying mechanism of Shuxin decoction against myocardial ischemia/reperfusion injury with diabetes

BACKGROUND Patients with diabetes mellitus are at higher risk of myocardial ischemia/reperfusion injury(MI/RI).Shuxin decoction(SXT)is a proven recipe modification from the classic herbal formula"Wu-tou-chi-shi-zhi-wan"according to the traditional Chinese medicine theory.It has been successfully used to alleviate secondary MI/RI in patients with diabetes mellitus in the clinical setting.However,the underlying mechanism is still unclear.AIM To further determine the mechanism of SXT in attenuating MI/RI associated with diabetes.METHODS This paper presents an ensemble model combining network pharmacology and biology.The Traditional Chinese Medicine System Pharmacology Database was accessed to select key components and potential targets of the SXT.In parallel,therapeutic targets associated with MI/RI in patients with diabetes were screened from various databases including Gene Expression Omnibus,DisGeNet,Genecards,Drugbank,OMIM,and PharmGKB.The potential targets of SXT and the therapeutic targets related to MI/RI in patients with diabetes were intersected and subjected to bioinformatics analysis using the Database for Annotation,Visualization and Integrated Discovery.The major results of bioinformatics analysis were subsequently validated by animal experiments.RESULTS According to the hypothesis derived from bioinformatics analysis,SXT could possibly ameliorate lipid metabolism disorders and exert anti-apoptotic effects in MI/RI associated with diabetes by reducing oxidized low density lipoprotein(LDL)and inhibiting the advanced glycation end products(AGE)-receptor for AGE(RAGE)signaling pathway.Subsequent animal experiments confirmed the hypothesis.The treatment with a dose of SXT(2.8 g/kg/d)resulted in a reduction in oxidized LDL,AGEs,and RAGE,and regulated the level of blood lipids.Besides,the expression of apoptosis-related proteins such as Bax and cleaved caspase 3 was down-regulated,whereas Bcl-2 expression was up-regulated.The findings indicated that SXT could inhibit myocardial apoptosis and improve cardiac function in MI/RI in diabetic rats.CONCLUSION This study indicated the active components and underlying molecular therapeutic mechanisms of SXT in MI/RI with diabetes.Moreover,animal experiments verified that SXT could regulate the level of blood lipids,alleviate cardiomyocyte apoptosis,and improve cardiac function through the AGE-RAGE signaling pathway.

Effect of rosiglitazone on rabbit model of myocardial ischemia-reperfusion injury

To explore mechanism and protective effect of rosiglitazone on myocardial ischemia reperfusion(I/R) injury.Methods:A total of 48 male Japanese white big-ear rabbits were randomly divided into control group(A),I/R group(B),low dose of rosiglitazone group(C),high dose of rosiglitazone group(D).Plasma concentration of and also reduced the concentration of plasma serum creatine kinase(CK),CK-MB.high-sensitivity C-reactive protein(hsCRP).ultrasuperoxide dismutase(SOD),malondialdehyde(MD.A).lactic acid glutathione skin peroxidase (C-SH-PX).nitric oxide(NO)and endothelin(ET) were measured 1 h later after I/R.Twenty-four hours after I/R the hearts were harvested for pathological and ultrastructural analysis.Area of myocardial infarction were tested.Results:Plasma concentration of CK,Ck-MB.hsCRP,NO. MDA and ET were decreased in C,D group compared with group B.Plasma concentration of T-SOD and GSH-Px were increased significantly in C.D group compared with group B.Compared with group B.pathological and ullraslructural changes in C and D group were slightly.There was significant difference in myocardial infarction area between group C.D and group B(P【0.05). Myocardial infarction area and arrhythmia rate were lower in group C,D compare with group B. Rosiglitazone may protect myocardium from I/R injury by enhancing T-SOD and GSH-Px concentration,inhibit inflammatory reaction,and improve endothelial function.

Myocardial ischemia-reperfusion injury:Possible role of melatonin

Our knowledge and understanding of the pathophysiology of coronary atherosclerosis has increased enormously over the last 20 years.Reperfusion through thrombolysis or percutaneous coronary angioplasty is the standard treatment for preventing acute myocardial infarction.Early reperfusion is an absolute prerequisite for survival of the ischemic myocardium,but reperfusion itself may lead to accelerated and additional myocardial injury beyond that generated by ischemia alone.These outcomes,in a range of reperfusion-associated pathologies,are collectively termed "reperfusion injuries".Reactive oxygen species are known to be produced in large quantities in the first few minutes of the post-ischemia reperfusion process.Similarly,scientific evidence from the last 15 years has suggested that melatonin has beneficial effects on the cardiovascular system.The presence of vascular melatoninergic receptor binding sites has been demonstrated;these receptors are functionally linked to vasoconstrictor or vasodilatory effects of melatonin.It has been shown that patients with coronary heart disease have a low melatonin production rate,especially those with higher risk of cardiac infarction and/or sudden death.Melatonin attenuates molecular and cellular damage resulting from cardiac ischemia-reperfusion in which destructive free radicals are involved.

Research progress of TRP channel's protective effect on myocardial ischemia-reperfusion injury

Transient receptor potential(TRP)channels are a type of cation channel located on the cell membrane.TRP channels are divided into 7 subfamilies(TRPC,TRPA,TRPM,TRPV,TRPN,TRPP and TRPML)and widely expressed in myocardial tissue.In recent years,with the application of gene knockout and transgenic model animals,it has been found that members of the TRP channel subfamilies TRPM,TRPC and TRPV are closely related to myocardial ischemia-reperfusion injury.The activation or inhibition of TRP channels participates in the regulation of myocardial ischemia-reperfusion injury,reduces the infarct area of the myocardium,and exerts a protective effect.Therefore,this paper first summarizes the structural characteristics of TRPM,TRPC,and TRPV and their distribution in the cardiovascular system,and then summarizes the mechanisms of TRPM,TRPC,and TRPV that regulate myocardial ischemia and reperfusion,which will provide a certain theoretical basis for treatment of myocardial ischemia-reperfusion injury.

Calpain system and its involvement in myocardial ischemia and reperfusion injury

Calpains are ubiquitous non-lysosomal Ca2+-dependent cysteine proteases also present in myocardial cytosol and mitochondria.Numerous experimental studies reveal an essential role of the calpain system in myocardial injury during ischemia,reperfusion and postischemic structural remodelling.The increasing Ca2+-content and Ca2+-overload in myocardial cytosol and mitochondria during ischemia and reperfusion causes an activation of calpains.Upon activation they are able to injure the contractile apparatus and impair the energy production by cleaving structural and functional proteins of myocytes and mitochondria.Besides their causal involvement in acute myocardial dysfunction they are also involved in structural remodelling after myocardial infarction by the generation and release of proapoptotic factors from mitochondria.Calpain inhibition can prevent or attenuate myocardial injury during ischemia,reperfusion,and in later stages of myocardial infarction.

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.

Comparative analysis of different cyclosporine A doses on protection after myocardial ischemia/reperfusion injury in rat

Objective:To investigate the protective effect of different cyclosporin A(CsA)doses on myocardial ischemia/reperfusion injury in rat models.Methods:A rat model of myocardial ischemia/reperfusion injury was established in vivo and the rats were randomly divided into four groups:placebo(PBS;T1),low-dose(CsA dose:1.0 mg/kg:T2),medium-dose(CsA dose:2.5 mg/kg:T3),and high-dose(CsA dose:5.0 mg/kg;T4)groups.Heart function indexes were monitored at different time points,the extent of myocardial infarction was assessed by Evans Blue-TTC staining,and creatine kinase MB mass and cardiac troponin 1 values were measured by biochemical assays.Results:Compared with the T1 and T2 groups,both the creatine kinase MB mass and cardiac troponin 1 were significantly lower in the T3 and T4 groups(P<0.05).The mean arterial pressure(MAP)and left ventricular systolic pressure(LVSP)decreased sequentially in each group,with the extending reperfusion time.Significant decreases in LVSP and MAP were observed in the T3 and T4 groups as compared to the T1 and T2 group(P<0.05)and the T2 group showed a significantly lower LVSP and MAP decline than the T1 group(P<0.05).Compared with the Tl group,the rats from the T2.T3,and T4 groups suffered from a significantly lower extent of myocardial infarction(P<0.05).Also,the a animals in the T3 and T4 groups had a significantly smaller extent of myocardial infarction than those in the T2 group(P<0.05).Conclusions:Various CsA doses exert different degrees of protection against ischemia/reperfusion injury,and this protective effect peaks at approximately 2.5 mg/kg in rat models.

The expression of oxidative stress genes related to myocardial ischemia reperfusion injury in patients with ST-elevation myocardial infarction

BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technology and try to determine the underlying mechanism.METHODS:The mononuclear cells were separated by ficoll centrifugation,and plasma total antioxidant capacity(T-AOC)was determined by the ferric reducing ability of plasma(FRAP)assay.The expression of toxic oxidative stress genes was determined and verified by oligo gene chip and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,gene ontology(GO)enrichment analysis was performed on DAVID website to analyze the potential mechanism further.RESULTS:The total numbers of white blood cells(WBC)and neutrophils(N)in the peripheral blood of STEMI patients(the AMI group)were significantly higher than those in the control group(WBC:11.67±4.85×10^(9)/L vs.6.41±0.72×10^(9)/L,P<0.05;N:9.27±4.75×10^(9)/L vs.3.89±0.81×10^(9)/L,P<0.05),and WBCs were significantly associated with creatine kinase-myocardial band(CK-MB)on the first day(Y=8.945+0.018X,P<0.05).In addition,the T-AOC was significantly lower in the AMI group comparing to the control group(12.80±1.79 U/mL vs.20.48±2.55 U/mL,P<0.05).According to the gene analysis,eight up-regulated differentially expressed genes(DEGs)included GADD45A,PRDX2,HSPD1,DNAJB1,DNAJB2,RAD50,TNFSF6,and TRADD.Four down-regulated DEGs contained CCNG1,CAT,CYP1A1,and ATM.TNFSF6 and CYP1A1 were detected by polymerase chain reaction(PCR)to verify the expression at different time points,and the results showed that TNFSF6 was up-regulated and CYP1A1 was down-regulated as the total expression.GO and kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis suggested that the oxidative stress genes mediate MIRI via various ways such as unfolded protein response(UPR)and apoptosis.CONCLUSIONS:WBCs,especially neutrophils,were the critical cells that mediating reperfusion injury.MIRI was regulated by various genes,including oxidative metabolic stress,heat shock,DNA damage and repair,and apoptosis-related genes.The underlying pathway may be associated with UPR and apoptosis,which may be the novel therapeutic target.

MicroRNA-15a/b are up-regulated in response to myocardial ischemia/reperfusion injury

ObjectiveSeveral 研究显示了 miR-15a， miR-15b 和 miR-16 可以是 apoptosis 的重要管理者。后来稀释 apoptosis 能保护心肌层和还原剂梗塞尺寸，现在的学习被瞄准发现是否这些 miRNAs 参予调整心肌的局部缺血灌注( I/R )在受到 I/R 的老鼠心的 injury.MethodsApoptosis 被 TUNEL 试金在 vivo 检测，当流动 cytometry 分析由 Annexin V/PI 列在后面时，在 vitro 的两倍污点被用来在受到 hypoxia/reoxygenation ( H/R )的有教养的 cardiomyocytes 检测 apoptosis 。Taqman 即时量的 PCR 被用来证实 miR-15a/15b/16 是否涉及心脏的 I/R 的规定，控制， I/R 或 H/R 的到那些的 H/R.ResultsCompared 导致了 cardiomyocytes 的 apoptosis 显著地在 vivo 两个都被增加(24.4%&#x000b1；9.4% 对 2.2%&#x000b1；1.9% ， P &#x0003c；0.01， n = 5 ) 并且在 vitro (14.12%&#x000b1；0.92% 对 2.22%&#x000b1；0.08%) 。 miR-15a 和 miR-15b 的表达式，然而并非 miR-16 ，在鼠标 I/R 模型，和结果被增加在 H/R model.ConclusionsOur 数据是一致的显示因此， miR-15 和 miR-15b 响应心脏的 I/R 损害是起来调整的 miR-15a/b 的下面规定可以是有希望的策略减少心脏的 I/R 损害导致的心肌的 apoptosis 。

Effect and mechanism of salvianolic acid B on the myocardial ischemiareperfusion injury in rats

Objective:To investigate the effect of salvianolic acid B on rats with myocardial ischemiareperfusion injury.Methods:SD rats were randomly divided into five groups(n=10 in each group):A sham operation group,B ischemic reperfusion group model group,C low dose salvianolic acid B group,D median dose salvianolic acid B group,E high dose salvianolic acid B group.One hour after establishment of the myocardial ischemia-reperfusion model,the concentration and the apoptotic index of the plasma level of myocardial enzymes(CTnⅠ,CKMB),SOD,MDA,NO,ET were,measured.Heart tissues were obtained and micro-structural changes were observed.Results:Compared the model group,the plasma CTnⅠ,CK-MB,MDA and ET contents were significantly increased,NO,T-SOD contents were decreased in the treatment group(group C,D,and E)(P<0.05);compared with group E,the plasma CTnⅠ,CKMB,MDA and ET levels were increased,the NO,T-SOD levels were decreased in groups C and D(P<0.05).Infarct size was significantly reduced,and the myocardial ultrastructural changes were improved significantly in treatment group.Conclusions:Salvianolic acid B has a significant protective effect on myocardial ischemia-reperfusion injury.It can alleviate oxidative stress,reduce calcium overload,improve endothelial function and so on.

The role of glycogen synthase kinase 3 beta in brain injury induced by myocardial ischemia/reperfusion injury in a rat model of diabetes mellitus

Myocardial ischemia/reperfusion injury can lead to severe brain injury.Glycogen synthase kinase 3 beta is known to be involved in myocardial ischemia/reperfusion injury and diabetes mellitus.However,the precise role of glycogen synthase kinase 3 beta in myocardial ischemia/reperfusion injury-induced brain injury is unclear.In this study,we observed the effects of glycogen synthase kinase 3 beta on brain injury induced by myocardial ischemia/reperfusion injury in diabetic rats.Rat models of diabetes mellitus were generated via intraperitoneal injection of streptozotocin.Models of myocardial ischemia/reperfusion injury were generated by occluding the anterior descending branch of the left coronary artery.Post-conditioning comprised three cycles of ischemia/reperfusion.Immunohistochemical staining and western blot assays demonstrated that after 48 hours of reperfusion,the structure of the brain was seriously damaged in the experimental rats compared with normal controls.Expression of Bax,interleukin-6,interleukin-8,terminal deoxynucleotidyl transferase d UTP nick end labeling,and cleaved caspase-3 in the brain was significantly increased,while expression of Bcl-2,interleukin-10,and phospho-glycogen synthase kinase 3 beta was decreased.Diabetes mellitus can aggravate inflammatory reactions and apoptosis.Ischemic post-conditioning with glycogen synthase kinase 3 beta inhibitor lithium chloride can effectively reverse these changes.Our results showed that myocardial ischemic post-conditioning attenuated myocardial ischemia/reperfusion injury-induced brain injury by activating glycogen synthase kinase 3 beta.According to these results,glycogen synthase kinase 3 beta appears to be an important factor in brain injury induced by myocardial ischemia/reperfusion injury.

Flow cytometric analysis of circulating microvesicles derived from myocardial ischemic preconditioning and cardioprotection of ischemia/reperfusion injury in rats

Objective: To establish a flow cytometric method to detect the alteration of phenotypes and concentration of circulating microvesicles(MVs) from myocardial ischemic preconditioning(IPC) treated rats(IPC-MVs), and to investigate the effects of IPC-MVs on ischemia/reperfusion(I/R) injury in rats. Methods: Myocardial IPC was elicited by three cycles of 5-min ischemia and 5-min reperfusion of the left anterior descending(LAD) coronary artery. Platelet-free plasma(PFP) was isolated through two steps of centrifugation at room temperature from the peripheral blood, and IPC-MVs were isolated by ultracentrifugation from PFP. PFP was incubated with anti-CD61, anti-CD144, anti-CD45 and anti-Erythroid Cells, and added 1, 2 μm latex beads to calibrate and absolutely count by flow cytometry. For functional research, I/R injury was induced by 30-min ischemia and 120-min reperfusion of LAD. IPC-MVs 7 mg/kg were infused via the femoral vein in myocardial I/R injured rats. Mean arterial blood pressure(MAP), heart rate(HR) and ST-segment of electrocardiogram(ECG) were monitored throughout the experiment. Changes of myocardial morphology were observed after hematoxylin-eosin(HE) staining. The activity of plasma lactate dehydrogenase(LDH) was tested by Microplate Reader. Myocardial infarct size was measured by TTC staining. Results: Total IPC-MVs and different phenotypes, including platelet-derived MVs(PMVs), endothelial cell-derived MVs(EMVs), leucocyte-derived MVs(LMVs) and erythrocyte-derived MVs(RMVs) were all isolated which were identified membrane vesicles(<1 μm) with corresponding antibody positive. The numbers of PMVs, EMVs and RMVs were significantly increased in circulation of IPC treated rats(P<0.05, respectively). In addition, at the end of 120-min reperfusion in I/R injured rats, IPC-MVs markedly increased HR(P<0.01), decreased ST-segment and LDH activity(P<0.05, P<0.01). The damage of myocardium was obviously alleviated and myocardial infarct size was significantly lowered after IPC-MVs treatment(P<0.01). Conclusion: The method of flow cytometry was successfully established to detect the phenotypes and concentration alteration of IPC-MVs, including PMVs, EMVs, LMVs and RMVs. Furthermore, circulating IPC-MVs protected myocardium against I/R injury in rats.

Epac1/Rap1 signaling pathway is involved in the pathogenesis of myocardial ischemia/reperfusion injury in rats

OBJECTIVE In this study we explored the role of Epac1-Rap1 pathway in the acute myocardial ischemia/reperfusion injury(MIRI) in vitro and in vivo.METHODS An acute myocardial ischemia/reperfusion injury model was established by the ligation of left anterior descending coronary.Myocardial architecture,fibers and apoptosis was evaluated by the Masson trichrome staining,Sirius red staining and TUNEL assay.H9c2 cells were subjected to hypoxia for 5 h followed by 1-h reoxygen.ation in vitro.Cell viability was measured by MTT assay and cellular injury was evaluated by measuring the release of lactate dehydrogenase(LDH).Western blot,real-time PCR and immunofluorescence were used to detect the expressions of Epac1 and relative downstream molecules.RESULTS Myocardial IR-induced cardiac apoptosis and accumulation of Epac1 and Rap1 in rat IR injury model.Direct Epac activation by 8-CPT(8-(4-chlorophenylthio)-2′-O-methyl-cAMP) exacerbated cardiomyocyte death and dysfunction following hypoxia-reoxygenation(H/R),selective activation of Epac in response to H/R was evident which enriched for cytosolic/membrane proteins and mRNA.Harmacological inhibitor of Epac(ESI-09) significantly ameliorated myocardial injury with the decline of Epac expression.Epac inhibitor and agonist studies also implicated the effect of Rap1,which is downstream of Epac in this pathway.The expression of Rap1 elevated when activated by Epac agonist and was blocked by Epac inhibitor.The same result was true for myocyte CaMK-II and intracellular calcium ions activation.Moreover,ESI-09 also increased ERK1/2 phosphorylation.CONCLUSION Our study reveal that Epac1/Rap1 signaling pathway is involved in the pathogenesis of myocardial I/R injury in rats,which provides evidence on the development of therapeutic strategies target this pathway for myocardial I/R injury.

CHANGES IN NEUROPEPTIDES AFTER MUSIC EXPOSURE 429Cardioprotective effect of ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injuryinduced in H9c2 cell

Post-resuscitation myocardial dysfunction(PRMD)is the most severe myocardial ischemia-reperfusion injury(MIRI)and is characterized by difficult treatment and poor prognosis.Research has shown the protective effects of the rational use of ivabradine(IVA)against PRMD,however,the molecular mechanisms of IVA remain unknown.In this study,an ischemia-reperfusion injury(IRI)model was established using hypoxic chambers.The results demonstrated that pretreatment with IVA reduced IRI-induced cytotoxicity and apoptosis.IVA attenuated mitochondrial damage,eliminated excess reactive oxygen species(ROS),suppressed IRI-induced ATP and NAD+,and increased the AMP/ATP ratio.We further found that IVA increased the mRNA levels of sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α)and upregulated the expression levels of phosphorylated AMP-activated protein kinase(p-AMPK)/AMPK,SIRT1,and PGC-1αproteins.Interestingly,no change in AMPK mRNA levels was observed.Cardiomyocyte energy metabolism significantly changed after IRI.The aim of this study was to demonstrate the cardioprotective effect of Ivabradine via the AMPK/SIRT1/PGC-1αsignaling pathway in myocardial ischemia/reperfusion injury-induced in H9c2 cell.

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.

Protective Effects of API_（0134） on Myocardial Ischemia and Reperfusion Injury

Previous studies have demonstrated that a crude extract from Chinese medicinal herb Andrographis Paniculata Nees (APN) could prevent myocardial ischemia and reperfusion injury. A refined extract API0134 was studied further. LAD was ligated for 90 min in 20 dogs and then reperfused for 120 min. The animals were randomly divided into 2 groups, API0134 treated group( n=10), 45 min after ischemia receiving a slow i. v. bolus of 1 mg/kg and then an infusion of 80 μg.kg-1/min for 60 min and control group (n=10) which was given only 5% glucose in saline. Result showed that the hemodynamics in API0134 treated group showed better effects of preventing the increase of the LVEDP and maintaining relatively normal CO as compared with control group. Ischemic ECGs were significantly milder. Malignant arrhythmia did not appear in API0134 treated group. After reperfusion, the infarct size was smaller ( 5. 06±2. 67 % vs 10. 45±3. 11 %, P < 0. 01 ), the damages found in myocardial ultrastructure were significantly milder. It is concluded that API0134 may protect the myocardium from ischemic reperfusion injury.

Cardioprotective effects of Salvia miltiorrhiza Bunge and Lignum dalbergiae odoriferae on rat myocardial ischemia/reperfusion injury

Aim Salvia miltiorrhiza Bunge （SM） and lignum dalbergiae odoriferae （DO） are both traditional Chi- nese medicine that have cardioprotective effects. Here, we further examined the combined effects of SM and DO on rat myocardial ischemia/reperfusion injury. The possible mechanism of SM and DO also were elucidated. Methods DO was divided into aqueous extract of lignum dalbergiae odoriferae （DOW） and lignum dalbergiae odoriferae oil （DOO）. Sprague-Dawley rats were randomized to seven groups： sham group, model group, treatment groups inclu- ding SM （10 g · kg^-1）, DOW （5 g · kg^-1）, DOO （0.5 ml · kg^-1）, SM ＋ DOW （10 g · kg^-1 ＋ 5 g · kg^-1）, SM ＋ DOO （ 10 g · kg^-1 ＋ 0. 5 ml · kg^-1）. Rats were pretreated with homologous drug for 7 days and then subjec- ted to 30 rain of ischemia followed by 180 rain of reperfusion. Electrocardiogram （ECG） and heart rate were moni- tored and recorded continuously. At the end of reperfusion, blood samples were collected to determine the serum levels of creatine kinase-MB （CK-MB） and lactate dehydrogenase （LDH）. Hearts were harvested to assess heart- body rate, infarct size and histopathological changes as well. Maximum and minimum effective points were deter- mined by measuring indicators associate with myocardial injury at different time-points of reperfusion （Smin, 15min, 30min, 45rain, 60min, 120min, 180min）. The potential therapeutic mechanism of SM and SM ＋ DOO were carried out by detecting superoxide dismutase （SOD）, malondialdehyde （MDA）, tumor necrosis factor-alpha （TNF-alpha） and interleukin 6 （IL-6）. Results The results showed SM and DO can ameliorate cardiac function respectively, and this cardioprotective effect was further strengthened by their combinations. Among all the combi- nations, SM ＋ DOO showed predominant potential to improve ECG and heart rate, reduce heart-body rate （28.5% ＋ 1.4% , P 〈 0.01 vs model） and myocardial infarct size （ 20.96% ＋ 1.61% , P 〈 0.01 vs model, P 〈 0.05 vs SM） , attenuate histopathological damage, decrease the levels of CK-MB and LDH （P 〈 0.01 vs model, P 〈 0.05 vs SM）. The maximum effective points of SM and SM ＋ DOO were 15min and 30rain respectively, and the minimum effective points of them were 180rain. In reducing serum level of MDA, TNF-alpha, IL-6 and increasing SOD activ- ity, SM ＋ DOO was similar to SM. Conclusion The results of this study indicated that SM ＋ DOO have combined effects that are highly effective than single pretreatment against myocardial ischemie reperfusion injury in rats. The possible mechanism of SM and DO were likely through its anti-oxidant and anti-inflammatory properties, and thus may be an effective and promising medicine for both prophylaxis and treatment of ischemic heart disease.

Blocking the Aryl Hydrocarbon Receptor Alleviates Myocardial Ischemia/Reperfusion Injury in Rats

Objective Restoring the blood perfusion of ischemic heart tissues is the main treatment for myocardial ischemia.However,the accompanying myocardial ischemia reperfusion injury(IRI)would aggravate myocardial damage.Previous studies have confirmed that aryl hydrocarbon receptor(AhR)is closely correlated to kidney and intestinal IRI.The present study aimed to explore the relationship between AhR and myocardial IRI.Methods An oxygen glucose deprivation/reoxygenation(OGD/R)model of H9c2 cells and an ischemia/reperfusion(I/R)model of Sprague-Dawley rat myocardium were established.OGD/R cells and myocardial IRI rats were treated with different concentrations of the AhR antagonist CH-223191 or agonist 6-formylindolo[3,2-b]carbazole(FICZ).Under the conditions of normoxia and hypoxia/reoxygenation,the activity of cardiomyocytes,lactate dehydrogenase(LDH)and cell reactive oxygen species(ROS)were detected.In rats,myocardial pathological damage and markers of myocardial injury were detected.Results According to the results of the cell viability,LDH and ROS tests in vitro,both CH-223191 and FICZ showed no myocardial protection under OGD/R conditions.However,the histological staining and analysis of myocardial injury marker LDH in vitro revealed that CH-223191 could significantly reduce the myocardial IRI.Conclusion AhR exhibited a different effect on myocardial IRI in vitro and in vivo.In vivo,CH-223191 could significantly alleviate the myocardial IRI,suggesting that inhibition of AhR may play a role in myocardial protection,and AhR may serve as a potential treatment target for myocardial IRI.

Progress in protective effect and mechanism of 6-gingerol on myocardial ischemia/reperfusion injury

The morbidity and mortality of cardiovascular diseases are very high,which has attracted more and more attention all over the world.Common treatment methods for clinical treatment of acute myocardial infarction include direct percutaneous coronary intervention and coronary artery bypass grafting,which can quickly restore blocked coronary blood flow and reduce the infarct size.However,the inevitable ischemia/reperfusion injury will occur during the recovery of coronary blood flow,its pathological mechanism is complicated,and the Western medicine countermeasures are very limited.Among the current drugs for the treatment of cardiovascular diseases,traditional Chinese medicine has become a research hotspot due to its multiple targets,safety,and low side effects.Ginger is the fresh rhizome of Zingiber officinale Rosc.,a perennial herbaceous plant in the ginger family.It is a dual-purpose resource of medicine and food.Ginger has the functions of relieving the appearance and dispelling cold,warming up and relieving vomiting,resolving phlegm and relieving cough,and relieving fish and crab poison.The chemical components of ginger mainly include volatile oil,gingerol,diphenylheptane,etc..Among them,6-gingerol,as the main active component of gingerols,has obvious pharmacological effects in myocardial protection,anti-oxidation,anti-inflammatory,etc..Studies have shown that 6-gingerol protects myocardium mainly through anti-oxidative stress,anti-inflammatory,inhibiting cell apoptosis,and preventing calcium influx.①Anti-oxidative stress:oxidative stress is a state where oxidation and anti-oxidation in the body are out of balance,and it is also an important factor leading to myocardial damage.Many studies have confirmed that 6-gingerol has an antioxidant effect,and it is considered a natural antioxidant.6-gingerol can significantly reduce the degree of oxidative stress and the level of reactive oxygen species caused by cardiomyocyte damage,and has a significant cardioprotective effect.②Anti-inflammatory:inflammation can cause substantial cell damage and organ dysfunction,which is another important cause of myocardial damage.6-gingerol can reduce the levels of inflammatory factors such as interleukin-6,interleukin-1β,and tumor necrosis factor-αin cardiomyocytes,and at the same time inhibit the TLR4/NF-κB signaling pathway,an important regulatory pathway of inflammation,showing that it may improve myocardial damage through anti-inflammatory effects.③Inhibition of apoptosis:apoptosis is a complex and orderly process in the autonomous biochemical process of cells,and one of the main mechanisms of myocardial injury.This process can be roughly divided into three pathways:mitochondria,endoplasmic reticulum,and death receptors.Among them,the mitochondrial pathway plays an important role,and Bcl-2 and Bax located upstream of this pathway can regulate the entire process of cell apoptosis by regulating the permeability of the mitochondrial membrane.Studies have found that the preventive application of 6-gingerol can reduce cell damage,reduce the number of apoptotic cells,reduce the activity of Bax and caspase-3,and increase the expression of Bcl-2.Therefore,6-gingerol pretreatment can reduce the damage of cardiomyocytes,and its mechanism may be related to the inhibition of apoptosis.④Prevent calcium influx:calcium overload is involved in the pathogenesis of myocardial ischemic injury,which may be related to excessive contracture,arrhythmia,and mitochondrial Ca2+accumulation that impairs myocardial function.6-gingerol inhibits the increase of intracellular Ca2+concentration by inhibiting L-type calcium current,thereby reducing extracellular Ca2+influx,thereby avoiding calcium overload and playing a cardioprotective effect.In summary,6-gingerol can effectively treat and improve myocardial ischemia/reperfusion injury,and it has great development potential in the fields of medicine and health products.