OBJECTIVE: To examine the effect of Shenmai Injection (SMJ) on ferroptosis during myocardial ischemia reperfusion (I/R) injury in rats and the underlying mechanism. METHODS: A total of 120 SPF-grade adult male SD rats, weighing 220-250 g were randomly divided into different groups according to a random number table. Myocardial I/R model was established by occluding the left anterior descending artery for 30 min followed by 120 min of reperfusion. SMJ was injected intraperitoneally at the onset of 120 min of reperfusion, and erastin (an agonist of ferroptosis), ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) and ML385 (an inhibitor of nuclear factor erythroid-2 related factor 2 (Nrf2)) were administered intraperitoneally separately 30 min before myocardial ischemia as different pretreatments. Cardiac function before ischemia, after ischemia and after reperfusion was analysed. Pathological changes in the myocardium and the ultrastructure of cardiomyocytes were observed, and the myocardial infarction area was measured. Additionally, the concentration of Fe²⁺ in heart tissues and the levels of creatine kinase-MB (CK-MB), troponin I (cTnl), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum were measured using assay kits, and the expressions of Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) were examined by Western blot. RESULTS: Compared with the sham group, I/R significantly injured heart tissues, as evidenced by the disordered, ruptured and oedematous myocardial fibres; the increases in infarct size, serum CK-MB, cTnI and MDA levels, and myocardial Fe²⁺ concentrations; and the decreases in SOD activity (P<0.05). These results were accompanied by ultrastructural alterations to the mitochondria, increased expression of ACSL4 and inhibited the activation of Nrf2/GPX4 signalling (P<0.05). Compared with I/R group, pretreatment with 9 mL/kg SMJ and 2 mg/kg Fer-1 significantly reduced myocardial I/R injury, Fe²⁺ concentrations and ACSL4 expression and attenuated mitochondrial impairment, while 14 mg/kg erastin exacerbated myocardial I/R injury (P<0.05). In addition, cardioprotection provided by 9 mL/kg SMJ was completely reversed by ML385, as evidenced by the increased myocardial infarct size, CK-MB, cTnI, MDA and Fe²⁺ concentrations, and the decreased SOD activity (P<0.05). CONCLUSIONS Ferroptosis is involved in myocardial I/R injury. Pretreatment with SMJ alleviated myocardial I/R injury by activating Nrf2/GPX4 signalling-mediated ferroptosis, thereby providing a strategy for the prevention and treatment of ischemic heart diseases.
Animals ; Male ; Rats ; Coenzyme A ; Creatine Kinase ; Ferroptosis ; Ligases ; Malondialdehyde ; Myocardial Infarction/drug therapy* ; Myocardial Ischemia/drug therapy* ; Myocardial Reperfusion Injury/pathology* ; Myocytes, Cardiac/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Rats, Sprague-Dawley ; Superoxide Dismutase/metabolism* ; Troponin I

OBJECTIVETo observe the in vivo effect of Danlou Tablet (, DLT) on myocardial ischemia and reperfusion (I/R) injury.

METHODSDLT effects were evaluated in mouse heart preparation using 30-min coronary occlusion followed by 24-h reperfusion and compared among sham group (n=6), I/R group (n=8), IPC group (ischemia preconditioning, n=6) and DLT group (I/R with DLT pretreatment for 3 days, 750 mg•kg•day, n=8). The effects of DLT were characterized in infarction size (IS) compared with risk region (RR) and left ventricle using the Evans blue/triphenyltetrazolium chloride double dye staining method in vivo. Furthermore, the dose-dependent effect of DLT on I/R injury was evaluated by double staining method. Five different concentrations of DLT (0.625, 1.25, 2.5, 5 and 10 g•kg•day) were chosen in this study, and dose-response curve of DLT was obtained on these data.

RESULTSThe ratio of IS to left ventricle was significantly smaller in the DLT and IPC groups than the I/R group (P<0.05 or P<0.01), the ratio of IS to RR was also reduced in the DLT and IPC groups (P<0.01), while there were no differences in RR among the four groups (P>0.05). Experiments showed incidence of arrhythmias was reduced in the DLT group (P<0.01). Furthermore, DLT produced a dose-dependent inhibitory effect with a half maximal inhibitory concentration of 1.225 g•kg•day.

CONCLUSIONSOur research concluded that DLT was effective in reducing I/R injury in mice, and provided experimental supports for the clinical use of DLT.

Animals ; Arrhythmias, Cardiac ; drug therapy ; pathology ; physiopathology ; Body Temperature ; drug effects ; Cardiotonic Agents ; pharmacology ; therapeutic use ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Heart Rate ; drug effects ; Heart Ventricles ; drug effects ; pathology ; physiopathology ; Male ; Mice, Inbred C57BL ; Myocardial Reperfusion Injury ; drug therapy ; pathology ; physiopathology ; Risk Factors ; Tablets

OBJECTIVETo analyze the effects of salvianolate on myocardial infarction in a murine in vivo model of ischemia and reperfusion (I/R) injury.

METHODSMyocardial I/R injury model was constructed in mice by 30 min of coronary occlusion followed by 24 h of reperfusion and pretreated with salvianolate 30 min before I/R (SAL group). The SAL group was compared with SHAM (no I/R and no salvianolate), I/R (no salvianolate), and ischemia preconditioning (IPC) groups. Furthermore, an ERK1/2 inhibitor PD98059 (1 mg/kg), and a phosphatidylinositol-3-kinase (PI3-K) inhibitor, LY294002 (7.5 mg/kg), were administered intraperitoneal injection (i.p) for 30 min prior to salvianolate, followed by I/R surgery in LY and PD groups. By using a double staining method, the ratio of the infarct size (IS) to left ventricle (LV) and of risk region (RR) to LV were compared among the groups. Correlations between IS and RR were analyzed. Western-blot was used to detect the extracellular signal-regulated kinase 1/2 (ERK1/2) and protein kinase B (AKT) phosphorylation changes.

RESULTSThere were no significant differences between RR to LV ratio among the SHAM, I/R, IPC and SAL groups (P>0.05). The SAL and IPC groups had IS of 26.1%±1.4% and 22.3%±2.9% of RR, respectively, both of which were significantly smaller than the I/R group (38.5%±2.9% of RR, P<0.05, P<0.01, respectively). Moreover, the phosphorylation of ERK1/2 was increased in SAL group (P<0.05), while AKT had no significant change. LY294002 further reduced IS, whereas the protective role of salvianolate could be attenuated by PD98059, which increased the IS. Additionally, the IS was not linearly related to the RR (r=0.23, 0.45, 0.62, 0.17, and 0.52 in the SHAM, I/R, SAL, LY and PD groups, respectively).

CONCLUSIONSalvianolate could reduce myocardial I/R injury in mice in vivo, which involves an ERK1/2 pathway, but not a PI3-K signaling pathway.

Animals ; Blotting, Western ; Cardiotonic Agents ; pharmacology ; therapeutic use ; Flavonoids ; pharmacology ; Heart Ventricles ; drug effects ; pathology ; MAP Kinase Signaling System ; drug effects ; Male ; Mice, Inbred C57BL ; Mitogen-Activated Protein Kinase 1 ; metabolism ; Mitogen-Activated Protein Kinase 3 ; metabolism ; Myocardial Reperfusion Injury ; drug therapy ; enzymology ; pathology ; Organ Size ; drug effects ; Phosphorylation ; drug effects ; Plant Extracts ; chemistry ; pharmacology ; therapeutic use ; Protein Kinase Inhibitors ; pharmacology ; Staining and Labeling

BACKGROUNDPercutaneous coronary intervention (PCI) could develop periprocedural myocardial infarction and inflammatory response and statins can modify inflammatory responses property. The aim of this study was to evaluate whether short-term high-dose atorvastatin therapy can reduce inflammatory response and myocardial ischemic injury elicited by PCI.

METHODSFrom March 2012 to May 2014, one hundred and sixty-five statin-naive patients with unstable angina referred for PCI at Department of Cardiology of the 306th Hospital, were enrolled and randomized to 7-day pretreatment with atorvastatin 80 mg/d as high dose group (HD group, n = 56) or 20 mg/d as normal dose group (ND group, n = 57) or an additional single high loading dose (80 mg) followed 6-day atorvastatin 20 mg/d as loading dose group (LD group, n = 52). Plasma C-reactive protein (CRP) and interleukin-6 (IL-6) levels were determined before intervention and at 5 minutes, 24 hours, 48 hours, 72 hours, and 7 days after intervention. Creatine kinase-myocardial isoenzyme (CK-MB) and cardiac troponin I (cTnI) were measured at baseline and then 24 hours following PCI.

RESULTSPlasma CRP and IL-6 levels increased from baseline after PCI in all groups. CRP reached a maximum at 48 hours and IL-6 level reached a maximum at 24 hours after PCI. Plasma CRP levels at 24 hours after PCI were significantly lower in the HD group ((9.14±3.02) mg/L) than in the LD group ((11.06±3.06) mg/L) and ND group ((12.36±3.08) mg/L, P < 0.01); this effect persisted for 72 hours. IL-6 levels at 24 hours and 48 hours showed a statistically significant decrease in the HD group ((16.19±5.39) ng/L and (14.26±4.12) ng/L, respectively)) than in the LD group ((19.26±6.34) ng/L and (16.03±4.08) ng/L, respectively, both P < 0.05) and ND group ((22.24±6.98) ng/L and (17.24±4.84) ng/L, respectively). IL-6 levels at 72 hours and 7 days showed no statistically significant difference among the study groups. Although PCI caused a significant increase in CK-MB and cTnI at 24 hours after the procedure in all groups, the elevated CK-MB and cTnI values were lower in the HD group ((4.71±4.34) ng/ml and (0.086±0.081) ng/ml, respectively) than in the ND group ((7.24±6.03) ng/ml and (0.138±0.103) ng/ml, respectively, both P < 0.01) and LD group ((6.80±5.53) ng/ml and (0.126±0.101) ng/ml, respectively, both P < 0.01).

CONCLUSIONShort-term high-dose atorvastatin treatment before PCI significantly reduced systemic inflammatory response and myocardial ischemic injury elicited by PCI.

Aged ; Angina, Unstable ; therapy ; Atorvastatin Calcium ; administration & dosage ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Myocardial Reperfusion Injury ; drug therapy ; Myocardium ; pathology ; Percutaneous Coronary Intervention ; Systemic Inflammatory Response Syndrome ; drug therapy ; Treatment Outcome

Recent studies have documented that Janus-activated kinase (JAK)-signal transducer and activator of transcription (STAT) pathway can modulate the apoptotic program in a myocardial ischemia/reperfusion (I/R) model. To date, however, limited studies have examined the role of JAK3 on myocardial I/R injury. Here, we investigated the potential effects of pharmacological JAK3 inhibition with JANEX-1 in a myocardial I/R model. Mice were subjected to 45 min of ischemia followed by varying periods of reperfusion. JANEX-1 was injected 1 h before ischemia by intraperitoneal injection. Treatment with JANEX-1 significantly decreased plasma creatine kinase and lactate dehydrogenase activities, reduced infarct size, reversed I/R-induced functional deterioration of the myocardium and reduced myocardial apoptosis. Histological analysis revealed an increase in neutrophil and macrophage infiltration within the infarcted area, which was markedly reduced by JANEX-1 treatment. In parallel, in in vitro studies where neutrophils and macrophages were treated with JANEX-1 or isolated from JAK3 knockout mice, there was an impairment in the migration potential toward interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1), respectively. Of note, however, JANEX-1 did not affect the expression of IL-8 and MCP-1 in the myocardium. The pharmacological inhibition of JAK3 might represent an effective approach to reduce inflammation-mediated apoptotic damage initiated by myocardial I/R injury.
Animals ; Apoptosis/drug effects ; Cell Movement/drug effects ; Chemokines/pharmacology ; Heart Function Tests/drug effects ; Inflammation/pathology ; Janus Kinase 3/*antagonists & inhibitors/metabolism ; Macrophages/drug effects/metabolism/pathology ; Male ; Mice ; Mice, Inbred C57BL ; Myocardial Reperfusion Injury/drug therapy/*enzymology/physiopathology/*prevention & control ; Myocardium/enzymology/pathology ; Myocytes, Cardiac/drug effects/metabolism/pathology ; Neutrophils/drug effects/metabolism/pathology ; Quinazolines/pharmacology/therapeutic use

OBJECTIVETo observe the protective effect of Yixinshu capsule on myocardial ischemia reperfusion injury (MIRI) in SD rats.

METHODSixty healthy SD rats were randomized into six groups: sham group, MIRI model group, Xinsuning capsule group, low, middle or high dose Yixinshu capsule. Acute MIRI rat models were created by reperfusion for 120 min after anterior interventricular branch of the left coronary artery for 30 min. The serum creatine kinase (CK), lactic dehydrogenase (LDH), aspartate aminotransferase (AST) and malondialdehyde(MDA), blood viscosity, and infarction area of myocardium were determined.

RESULTYixinshu capsule could reduce serum CK, LDH, AST and LDH activity, improve the blood viscosity, and reduced the myocardial infarct size.

CONCLUSIONYixinshu capsule can protect against MIRI in rats.

Animals ; Blood Viscosity ; drug effects ; Capsules ; Drugs, Chinese Herbal ; therapeutic use ; Lipid Peroxidation ; drug effects ; Male ; Myocardial Infarction ; drug therapy ; metabolism ; pathology ; Myocardial Reperfusion Injury ; prevention & control ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effects and mechanisms of hawthorn leaves flavonoids (HLF) on acute myocardial ischemia/reperfusion in anesthetized dogs.

METHODSThe acute ischemia models were prepared by ligating left anterior descending (LAD) artery for 60 min. Qualified 15 male dogs were randomly divided into 3 groups with 5 in each group: blank control (treated with normal saline 3 mL/kg) group, HLF low dosage (5 mg/kg) group and high dosage (10 mg/kg) group, with an once injection through a femoral vein 5 min before reperfusion. Epicardial electrocardiogram was adopted to measure the scope and degree of myocardial ischemia. Simultaneously, neutrophil infiltration in infarct (Inf) and remote site (RS) of myocardial tissue was measured by myeloperoxidase (MPO) activity assay. The serum interleukin-1 (IL-1) and tumor necrosis factorα (TNF-α) content were quantified by radioimmuno-assay. Furthermore, expression of G protein-coupled receptor kinase 2 (GRK2) and nuclear factor κB (NF-κB) in Inf and RS tissue were detected by Western blotting technique.

RESULTSIschemia and reperfusion increased the MPO activity and IL-1 and TNF-α content. HLF (10 and 5 mg/kg) could significantly decrease the degree and scope of myocardial ischemia; markedly inhibit the increase of MPO activity, and IL-1 and TNF-α content induced by myocardial ischemia/infarction. Furthermore, HLF increased GRK2 expression and inhibited NF-κB expression in Inf tissue.

CONCLUSIONHLF could improve the situation of acute myocardial ischemia and inhibit the inflammation in anesthetized dogs, which might be due to its increasing effect on the GRK2 and NF-κB expressions.

Anesthesia ; Animals ; Crataegus ; chemistry ; Dogs ; Drug Evaluation, Preclinical ; Flavonoids ; pharmacology ; therapeutic use ; Inflammation ; etiology ; prevention & control ; Male ; Myocardial Ischemia ; complications ; drug therapy ; pathology ; Myocardial Reperfusion Injury ; complications ; drug therapy ; Neutrophil Infiltration ; drug effects ; Plant Extracts ; pharmacology ; therapeutic use ; Plant Leaves ; chemistry ; Random Allocation

OBJECTIVETo identify the underlying mechanisms of the protective effects of Dingxin Recipe (: , DXR), a Chinese compound prescription that has been used clinically in China for more than 20 years, on ischemia/reperfusion (I/R)-induced arrhythmias in rat model.

METHODSA total of 30 rats were randomly divided into three groups: sham group, I/R group, and DXR-pretreated I/R (DXR-I/R) group. Rats in the DXR-DXRI/R group were intragastrically administrated with DXR (12.5 g/kg per day) for consecutive 7 days, while rats I/in the sham and I/R groups were administrated with normal saline. Arrhythmias were introduced by I/R and electrocardiograms (ECG) were recorded. Two-dimensional (2-D) polyacrylamide gel electrophoresis and matrix-matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used to identify assisted differentially expressed proteins. Immunohistochemistry, real-time quantitative polymerase chain reaction (RQ-RQPCR), Western blot, and enzyme-linked immunosorbent assay (ELISA) were performed to analyze proteins PCR), obtained in the above experiments.

RESULTSDXR significantly reduced the incidence and mean duration of ventricular tachycardia and ventricular fibrillation and dramatically decreased the mortality, as well as arrhythmia score, compared with those of the I/R group. Among successfully identified proteins, prohibitin (PHB) and heart fatty acid binding protein (hFABP) were up-regulated in DXR-pretreated I/R rats compared with those of the I/R rats. In addition, compared with the I/R group, the level of glutathione (GSH) was elevated accompanied by reduced expressions of interleukin-6 (IL-6) and neutrophil infiltration in I/R rats with DXR pretreatment.

CONCLUSIONSDXR could alleviate I/R-induced arrhythmias, which might be related to increased expression of PHB. The enhanced expression of PHB prevented against the depletion of GSH and consequently inhibited apoptosis of cardiomyocytes. Furthermore, up-regulation of PHB might ameliorate I/R-induced cell death and leakage of hFABP by suppressing neutrophil infiltration and IL-6 expressions.

Animals ; Arrhythmias, Cardiac ; etiology ; prevention & control ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Electrophoresis, Gel, Two-Dimensional ; Fatty Acid Binding Protein 3 ; Fatty Acid-Binding Proteins ; metabolism ; Glutathione ; metabolism ; Heart Ventricles ; drug effects ; metabolism ; pathology ; Immunohistochemistry ; Inflammation ; complications ; metabolism ; pathology ; Interleukin-6 ; metabolism ; Male ; Myocardial Infarction ; complications ; drug therapy ; pathology ; Neutrophil Infiltration ; drug effects ; Peptide Mapping ; Proteomics ; Rats ; Rats, Wistar ; Reperfusion Injury ; complications ; Repressor Proteins ; metabolism ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Spectrophotometry ; Up-Regulation ; drug effects

OBJECTIVETo explore the synergistic protection of Danhong Injection (丹红注射液, DHI) and ischemic postconditioning on myocardial reperfusion injury in minipigs.

METHODSAcute myocardial infarction model was made by balloon occlusion in left anterior descending coronary artery (LAD) of minipigs, and then postconditioning was simulated through inflation/deflation of the angioplasty balloon. Minipigs were divided into four groups: the sham operation group (SH group), the ischemia/reperfusion group (I/R group), the ischemic postconditioning group (POC group) and DHI combined with ischemic postconditioning group (PAD group, DHI 20 mL through ear vein), six in each group. After 24-h continuous observation, myocardial infarction size was assessed by triphenyltetrazolium staining (TTC). Morphological changes of ischemic myocardium were observed by light microscopy, and cardiomyocyte ultrastructure was studied with electron microscopy. The superoxide dismutase (SOD) and malondialdehyde (MDA) activity in heart homogenates were measured by a biochemical method.

RESULTSThe myocardial infarction size was smaller in the POC group than in the I/R group (0.26 ± 0.02 vs. 0.37 ± 0.09, P<0.05), and the PAD group (0.14 ± 0.08) displayed a significantly reduced infarction size relative to the I/R group (P<0.01) and POC group (P<0.05). The damage of myocardial tissue was severe in the I/R group shown by light and electron microscopy: myocardial fibers disorder, sarcoplasmic dissolution, myofilament fracture, mitochondria swelling and even vacuolization formation and a large number of inflammatory cell infiltrations. Compared with the I/R group, reduction of reperfusion injury in the PAD group included more orderly arranged myocardial fibers, less infiltration of inflammatory cells and maintenance of mitochondrial integrity. Compared with the I/R group, the damage of myocardial tissue in the POC group was improved, but not as significant as that in the PAD group. SOD levels in the POC group and the PAD group were significantly higher than those in the I/R group (96.96 ± 13.43, 112.25 ± 22.75 vs. 76.32 ± 10.63, P<0.05), and MDA was significantly lower in the POC group and the PAD group compared to the I/R group (1.27 ± 0.19, 1.09 ± 0.21 vs. 1.47 ± 0.16, P<0.05).

CONCLUSIONDHI and ischemic postconditioning show a synergistic cardioprotection on myocardial reperfusion injury in minipigs.

Animals ; Coronary Angiography ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Injections ; Ischemic Postconditioning ; Malondialdehyde ; metabolism ; Myocardial Infarction ; complications ; pathology ; Myocardial Reperfusion Injury ; complications ; drug therapy ; prevention & control ; Myocardium ; enzymology ; pathology ; ultrastructure ; Superoxide Dismutase ; metabolism ; Swine ; Swine, Miniature

OBJECTIVE: To investigate the effect of isoflurane delayed preconditioning on the activation of caspase-3 and the expression of Bcl-2 in rabbit myocardium during ischemia reperfusion and the possible mechanism. METHODS: Forty New Zealand male white rabbits were randomly divided into 4 groups: a sham group (Group C), an I/R group, an isoflurane group (Group S), and an isoflurane + opioid recepters inhibitor group (Group N). Group S was exposed to 2.0% isoflurane for 2 h. Group N was given naloxone (6.0 mg/kg) before exposing to 2.0% isoflurane. Group C and Group I/R were exposed for 2 h to 100% oxygen, serving as untreated controls. Twenty-four hours later, Group S and Group N underwent 40 min of coronary occlusion followed by 2 h of reperfusion. At the end of the reperfusion, infarct size(IS) and area at risk(AAR) were defined by Evans and TTC staining. The myocardial ultrastructure was observed by electron microscopy. The levels of the myocardial Bcl-2 and caspase-3 expression were determined by Western blot. RESULTS: The caspase-3 activity of Group S was significantly lower than that of Group I/R(P<0.05). The IS was significantly reduced in Group S(19.7%+/-2.8%) as compared with Group I/R(37.8%+/-1.7%) (P<0.05). Microscopic examination showed less myocardial damage in Group S than in Group I/R. CONCLUSION Isoflurane delayed preconditioning can inhibit the apoptosis of myocardium by up-regulating the expression of Bcl-2 and down-regulating the activation of caspase-3, which may be part of the molecular mechanism of isoflurane delayed preconditioning on myocardial preservation.
Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Gene Expression Regulation ; drug effects ; Ischemic Preconditioning, Myocardial ; methods ; Isoflurane ; pharmacology ; therapeutic use ; Male ; Myocardial Ischemia ; drug therapy ; pathology ; Myocardial Reperfusion Injury ; prevention & control ; Myocardium ; metabolism ; ultrastructure ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rabbits ; Random Allocation