Metabolic Crosstalk between the Heart and Fat

It is now recognized that the heart can behave as a true endocrine organ, which can modulate the function of other tissues. Emerging evidence has shown that visceral fat is one such distant organ the heart communicates with. In fact, it appears that bi-directional crosstalk between adipose tissue and the myocardium is crucial to maintenance of normal function in both organs. In particular, factors secreted from the heart are now known to influence the metabolic activity of adipose tissue and other organs, as well as modulate the release of metabolic substrates and signaling molecules from the periphery. This review summarizes current knowledge regarding primary cardiokines and adipokines involved in heart-fat crosstalk, as well as implications of their dysregulation for cardiovascular health.

A glucose-insulin-potassium solution improves glucose intake in hypoxic cardiomyocytes by a differential expression of glucose transporters in a metabolic syndrome model

Among the last consequences of metabolic syndrome are cardiovascular complications such as infarcts. The hypoxic heartswitches its lipid-based metabolism to carbohydrates, and a glucose-insulin-potassium (GIK) solution can be the metabolicsupport to protect the organ. Due to the physiology and cardiac risks associated with the metabolic syndrome, we studied theeffect of GIK solution during hypoxia in a metabolic syndrome model by observing the participation of glucose transporters(GLUTs). The metabolic syndrome characteristics were established by giving a 30% sucrose drinking solution to Wistar ratsfor 24 weeks. The GIK solution’s effect on myocyte glucose uptake during hypoxia and oxygenation was observed using acolorimetric method, and Western blot technique visualized the GLUT participation. Oxygenated control myocytes consumed1.7 ± 0.2 µg of glucose per gram of fresh tissue per hour using the GLUT1, and during hypoxia, they incorporated 41.1%more glucose by GLUT1 and GLUT4. The GIK solution improved glucose uptake in oxygenation by 70.5% through GLUT1.In hypoxia, the uptake was 21% more than the hypoxic control group and by both GLUTs too. Oxygenated metabolicsyndrome myocytes uptake was similar to control cells but achieved by both carriers in oxygenation and hypoxia. Also, theGIK solution had a better response in both oxygenation (113%) and hypoxia (71%). Despite the metabolic energy disorders ofthis syndrome, the GIK solution protects cardiomyocytes, in conditions of hypoxia, through the modulation of both GLUTs.So, this solution can be considered a useful resource during a heart attack in cases of metabolic syndrome.

Protective effects of curcumin on oxidative stress injury of H9C2 cardiac myocytes induced by H2O2 / 国际中医中药杂志

Objective To study the protective effects of curcumin on oxidative stress injury of H9C2 cardiac myocytes induced by H2O2.Methods The oxidative stress injury model in H9C2 cardiac myocytes was established in vitro, and cells were divided into the control group, H2O2 group (200μmol/L), low- (10μmol/L), medium- (20μmol/L), high- (40μmol/L) dose curcumin, and each group set six holes. After H2O2 stimulation for 24 h, the morphology changes were observed by microscope, and the survival rates were measured using CCK8 method. The activity of LDH, CK, and AST, and the content of MDA in culture medium were detected, and the activities of SOD, CAT, and GSH-Px in cardiac myocytes were also determined.Results Compared with the H2O2 group, the activity of LDH (247.36 ± 28.04 U/L, 195.14 ± 21.37 U/L, 132.27 ± 16.33 U/Lvs. 247.58± 28.34 U/L), AST (67.27 ± 10.58 U/ml, 54.81 ± 8.60 U/ml, 42.14 ± 5.95 U/mlvs.84.34 ± 12.36 U/ml), CK (1.34 ± 0.66 U/ml, 0.95 ± 0.42 U/ml, 0.71 ± 0.39 U/ml vs.1.56 ± 0.74 U/ml) and the content of MDA (227.39 ± 32.05 nmol/ml, 185.11 ± 24.37 nmol/ml, 143.50 ± 16.37 nmol/mlvs. 274.19 ± 36.51 nmol/ml) in culture medium of curcumin were significantly decreased (P<0.05). The morphology of H9C2 cardiac myocytes in curcumin group was improved, the survival rate was significantly increased (P<0.05). The activity of SOD (17.67± 1.36 U/mg, 21.54 ± 1.72 U/mg, 28.37 ± 2.36 U/mgvs. 14.37 ± 1.22 U/mg), CAT (19.58 ± 3.87 U/mg, 25.34 ± 4.06 U/mg, 30.21 ± 4.83 U/mgvs. 14.77 ± 3.25 U/mg) and GSH-Px (1.99 ± 1.17 U/mg, 2.56 ± 1.29 U/mg, 3.04 ± 0.45 U/mgvs. 1.67 ± 0.87 U/mg) in cardiac myocytes were significantly increased (P<0.05). Conclusions Curcumin can effectively improve oxidative stress injury of H9C2 cardiac myocytes induced by H2O2, and curcumin has dose-dependent protective effects against the oxidative stress of H9C2 cardiac myocytes induced by H2O2.

Melatonin-Induced Protective Effects on Cardiomyocytes Against Reperfusion Injury Partly Through Modulation of IP3R and SERCA2a Via Activation of ERK1 / Efeitos Protetores Induzidos pela Melatonina nos Cardiomiócitos Contra Lesões de Reperfusão Parcialmente Através da Modulação Dde IP3R e SERCA por Meio da Ativação de ERK1

Resumo Background: Melatonin is a neuroendocrine hormone synthesized primarily by the pineal gland that is indicated to effectively prevent myocardial reperfusion injury. It is unclear whether melatonin protects cardiac function from reperfusion injury by modulating intracellular calcium homeostasis. Objective: Demonstrate that melatonin protect against myocardial reperfusion injury through modulating IP3R and SERCA2a to maintain calcium homeostasis via activation of ERK1 in cardiomyocytes. Methods: In vitro experiments were performed using H9C2 cells undergoing simulative hypoxia/reoxygenation (H/R) induction. Expression level of ERK1, IP3R and SERCA2a were assessed by Western Blots. Cardiomyocytes apoptosis was detected by TUNEL. Phalloidin-staining was used to assess alteration of actin filament organization of cardiomyocytes. Fura-2 /AM was used to measure intracellular Ca2+ concentration. Performing in vivo experiments, myocardial expression of IP3R and SERCA2a were detected by immunofluorescence staining using myocardial ischemia/ reperfusion (I/R) model in rats. Results: In vitro results showed that melatonin induces ERK1 activation in cardiomyocytes against H/R which was inhibited by PD98059 (ERK1 inhibitor). The results showed melatonin inhibit apoptosis of cardiomyocytes and improve actin filament organization in cardiomyocytes against H/R, because both could be reversed by PD98059. Melatonin was showed to reduce calcium overload, further to inhibit IP3R expression and promote SERCA2a expression via ERK1 pathway in cardiomyocytes against H/R. Melatonin induced lower IP3R and higher SERCA2a expression in myocardium that were reversed by PD98059. Conclusion: melatonin-induced cardioprotection against reperfusion injury is at least partly through modulation of IP3R and SERCA2a to maintain intracellular calcium homeostasis via activation of ERK1.

Resumo Fundamento: A melatonina é um hormônio neuroendócrino sintetizado principalmente pela glândula pineal que é indicado para prevenir efetivamente a lesão de reperfusão miocárdica. Não está claro se a melatonina protege a função cardíaca da lesão de reperfusão através da modulação da homeostase do cálcio intracelular. Objetivo: Demonstrar que a melatonina protege contra a lesão de reperfusão miocárdica através da modulação de IP3R e SERCA para manter a homeostase de cálcio por meio da ativação de ERK1 em cardiomiócitos. Métodos: Foram realizados experimentos in vitro usando células H9C2 submetidas a indução de hipoxia / reoxigenação simulada (H/R). O nível de expressão de ERK1, IP3R e SERCA foi avaliado por Western Blots. A apoptose de cardiomiócitos foi detectada por TUNEL. A coloração de faloidina foi utilizada para avaliar a alteração da organização de filamentos de actina dos cardiomiócitos. Fura-2 / AM foi utilizado para medir a concentração intracelular de Ca2+. Realizando experiências in vivo, a expressão miocárdica de IP3R e SERCA foi detectada por coloração com imunofluorescência usando modelo de isquemia miocárdica / reperfusão (I/R) em ratos. Resultados: resultados in vitro mostraram que a melatonina induz a ativação de ERK1 em cardiomiócitos contra H/R que foi inibida por PD98059 (inibidor de ERK1). Os resultados mostraram que a melatonina inibe a apoptose dos cardiomiócitos e melhora a organização do filamento de actina em cardiomiócitos contra H/R, pois ambas poderiam ser revertidas pela PD98059. A melatonina mostrou reduzir a sobrecarga de cálcio, além de inibir a expressão de IP3R e promover a expressão de SERCA através da via ERK1 em cardiomiócitos contra H/R. A melatonina induziu menor IP3R e maior expressão de SERCA no miocárdio que foram revertidas pela PD98059. Conclusão: a cardioproteção induzida pela melatonina contra lesão de reperfusão é pelo menos parcialmente através da modulação de IP3R e SERCA para manter a homeostase de cálcio intracelular via ativação de ERK1.

Protective effect of epigallocatechin-3-gallate on hypoxia/reoxygenation injury in cardiac myocytes and its mechanism / 中国药理学通报

Aim To observe the protective effect of epigallocatechin-3-gallate (EGCG) on hypoxia/reoxygenation (H/R) injury of cardiac myocytes and its mechanisms.Methods H9c2 cardiac myocytes were cultured in vitro and randomly divided into five groups:normal group(N group),H/R group,EGCG low dose group (L group),EGCG medium dose group (M group),and EGCG high dose group(H group).The cardiomyocyte H/R injury model was established and EGCG was pretreated.Cell survival rate was tested by CCK-8 method.The cell apoptotic rate was detected using Annexin V-FITC/PI double staining.The contents of total antioxidant capacity(T-AOC) and tumor necrosis factor α(TNF-α) in cell culture medium were tested according to the kit instructions.The protein expression of Akt and p-Akt was observed using Western blot,while the gene expressions of PI3K,Akt,caspase3 were detected by using fluorescence quantitative PCR method.Results Compared with model group,EGCG increased cell survival rate and reduced the apoptosis after H/R injury.Meanwhile,pretreatment EGCG improved the activity of T-AOC,reduced the level of TNF-α,up-regulated the expression of PI3K,Akt and p-Akt,and down-regulated the expression of caspase3.Conclusion EGCG reduces apoptosis and protects cardiac myocytes by influencing PI3K/Akt signal path

N-n-butyl haloperidol iodide protectsH9c2 cardiac myocytes against hypoxia/reoxygenationinjury through mitochondria-dependent apoptotic pathway / 中国药理学通报

Aim To investigate the effect of N-n-butyl haloperidol iodide(F2) on mitochondria-dependent apoptotic pathway of H9c2 cardiac myocytes during hypoxia/reoxygenation(H/R) injury.Methods The H/R models of H9c2 cardiac myocytes were established.The H9c2 cardiac myocytes were randomly divided into five groups: control group(C group), hypoxia/reoxygenation group(H/R group), F2 low concentration group(L), F2 medium concentration group(M), F2 high concentration group(H).Apoptotic rate was evaluated by flow cytometry(FCM).The levels of Cyto C, Bcl-2, Bax were observed by Western blot.Caspase-3 activity was measured with colorimetry.Results Compared with H/R group, F2 low, medium and high concentrations group could significantly decrease apoptosis rate and increase the ratio of Bcl-2 to Bax proteins and inhibit the release of Cyto C into the cytosolic fraction, and decrease caspase-3 activity.Conclusion F2 can protect H9c2 cardiac myocytes against H/R-induced injury through interfering in mitochondria-dependent pathway.

CFTR in Cardiovascular Functions / 中山大学学报(医学科学版)

Cystic fibrosis transmembrane conductance regulator(CFTR)is an ATP-gated,cAMP-dependent chloride channel. The basic biophysical and pathological functions of CFTR are related with the secretion of chloride ion in epithelial cells and tissues. Mutations in CFTR cause cystic fibrosis(CF),which is a rare but fatal autosomal recessive inheritant disease ,mainly affecting glan?dular epithelial function in respiratory tract ,intestinal and reproductive system. New drugs targeting human CFTR gene mutations have been developed to significantly prolong lifeand improve respiratory symptoms of CF patients. Recent evidence suggested that CFTR plays a functional role in vasoconstriction and the formation of myocardial action potential. As a channel protein ,CFTR may al?so functions as a multiprotein/channel complex ,which has been demonstrated in the development of cardiovascular diseases such as myocardial ischemia and pulmonary hypertension.

Análise histomorfométrica dos cardiomiócitos e deposição de colágeno no músculo cardíaco de ratas ooforectomizadas / Histomorphometric analysis of cardiomyocytes and collagen deposition in the heart muscle of ovariectomized rats

Esse estudo objetivou avaliar o efeito da ooforectomia sob os parâmetros histomorfométricos dos cardiomiócitos e quantificação de colágeno em ratas Wistar. Vinte ratas foram utilizadas e separadas em dois grupos: GI - ooforectomizada e GII - sham-ooforectomizada. Após a recuperação anestésica os animais foram acomodados em gaiolas e separados nas condições de ciclo claro/escuro 12/12h por um período de 6 meses. Passado o período experimental, os animais foram anestesiados, o coração retirado e mergulhado em formaldeído a 10%. Os fragmentos dos ventrículos foram submetidos ao processamento histológico e corados com hematoxilina e eosina. As análises histomorfométricas (área celular e área e volume nuclear) foram realizadas pelo microscópio de luz e software ImageJ versão 1.44. Os dados foram submetidos à análise ANOVA e quando significantes, complementados pelo teste t de student (p<0,001). Observou-se uma diminuição significativa das áreas celular e nuclear dos cardiomiócitos do grupo GI quando comparado ao grupo GII, bem como a área ocupada, pelo colágeno, no músculo cardíaco foi maior em GI, quando comparado a GII. Diante disso, conclui-se que as alterações observadas nos cardiomiócitos do grupo GI, sugerem uma maior atividade apoptótica nesse grupo, devido à diminuição dos níveis séricos do estrógeno provocado pela ooforectomia e o aumento da área ocupada pelo colágeno, no grupo ooforectomizado, está associada ao efeito cardioprotetor do estrógeno.

This study aimed to evaluate the effect of oophorectomy on the morphometric variables of cardiomyocytes and quantification collagen in Wistar rats. Twenty rats were used and divided into two groups: GI - ovariectomized and GII - sham-ovariectomized. After recovery from anesthesia the animals were housed in separate cages and under the conditions of light / dark cycle 12/12h for a period of six months. After the experimental period, the animals were anesthetized, the heart removed and immersed in 10% formaldehyde. The fragments of the ventricles were subjected to histological analysis and stained with hematoxylin and eosin. Histomorphometric analysis (cell area and nuclear area and volume) were performed by light microscopy and ImageJ software version 1.44. The data were submitted to ANOVA and when significant, complemented by Student's t test (p<0.001). There was a significant decrease in cellular and nuclear areas of the GI cardiomyocytes compared to GII and the area occupied by collagen was greater in cardiac muscle GI, when compared to GII. Therefore, it is concluded that the changes observed in the GI group cardiomyocytes, suggest a higher apoptotic activity in this group, due to decreased serum estrogen levels caused by ovariectomy and increased area occupied by collagen in oophorectomized group is associated the cardioprotective effect of estrogen.

Preparation of PCM modified liposome and evaluation of its myocardium targeting efficiency / 第二军医大学学报

Objective To prepare PCM modified liposome (PCM-LIP) containing enhanced green fluorescent protein expression plasmid (pEGFP) and to evaluate its myocardial targeting ability. Methods Liposome was prepared by film-ultrasonic, with PCM used as ligand and DOTAP as cationic lipid material. PCM-LIP containing pEGFP was prepared by incubating liposome with pEGFP at room temperature. The connecting method of PCM was optimized and the connection rate of PCM was determined. The characteristics of liposomes including encapsulation ability, morphology, particle size, zeta potential and stability in phosphate buffer solution (PBS) were observed. The transfection efficiency of liposomes into H9c2 cells was evaluated by inverted fluorescence microscopy and flow cytometry, so as to characterize their myocardial targeting ability and to determine the optimum dosage of PCM. Results PCM-LIP was prepared by insertion method and the amount of PCM accounted for 3% of the lipid. After incubation with pEGFP, PCM-LIP was spherical in shape, with the particle size being (261. 9±2. 2) nm, zeta potential being (-5. 0±0. 6) mV, and PCM-LIP was stable in PBS at -4℃ for 30 d. The transfection efficiency of PCM-LIP was significantly higher than that of unmodified liposome (P<0. 05). Conclusion PCM can improve the transfection efficiency of liposome into cardiomyocytes and PCM-LIP shows a satisfactory myocardial targeting ability.

Influence of microRNAs on cordiomyocyte viability in myocardial infarction and its therapeutic potential: Research progress / 第二军医大学学报

MicroRNAs (miRs), initially discovered in eukaryotes, are endogenous small noncoding RNAs that regulate gene expression. Myocardial infarction is a common cardiovascular event resulting in cardiac remodeling and subsequent chronic heart failure. A number of miRs have been reported to regulate important pathophysiological processes of myocardial infarction. They have multiple effects on the survival and proliferation of cardiomyocytes, which is of great significance to myocardial infarction and other ischemic heart diseases. In this review we introduced the general knowledge of myocardial infarction and miRs, and described several miRs which are crucial for survival and proliferation of cardiomyocytes. We also discussed the therapeutic potential and limitations of miRs in future treatment of myocardial infarction.

Effect of 1a,25(OH)2 D3 on circadian clock gene expression in cardiac myocytes / 中华实用儿科临床杂志

Objective To explore the effect of 1a,25(OH)2 D3 on circadian clock gene expressions in cardiac myocytes.Methods Cultured cardiac myocytes isolated from 7 -day -old Sprague -Dawley(SD)rats were identified by immunofluorescence.The medium including 1a,25 (OH)2 D3 (final concentrations were 0 nmol/L,1 nmol/L, 10 nmol/L,50 nmol/L and 100 nmol/L)were added to primary myocardial cells to culture for 2 h and then total RNA was extracted.Real -time polymerase chain reaction (RT -PCR)was applied to analyze myocardial cells circadian clock gene (Bmal1,Per2,Rev -erba)transcript levels to determine optimum concentration of 1a,25(OH)2 D3 .Then, the primary myocardial cells cultured for 72 h were divided into 3 groups:the control group was of serum -free culture medium;serum shock group was of DMEMcontaining 50%volume fraction of horse serum cultured 2 h;1a,25(OH)2 D3 treatment group receiving 1a,25 (OH)2 D3 at optimal concentration cultured 2 h.The cells were collected at 7 time points (0 h,4 h,8 h,12 h,16 h,20 h,24 h)and then total RNA was extracted.RT -PCR was applied to analyze circa-dian clock gene (Bmal1,Per2,Rev -erba)transcript levels in the myocardial cells.Results In the presence of 50 nmol/L 1 a,25(OH)2 D3 ,the Bmal1 mRNA expression showed the highest level,but the Per2 and Rev -erba mRNA expression levels were minimum.Compared with the control group,both 1a,25 (OH)2 D3 treatment group and serum shock group caused day -cycle rhythmic oscillation in circadian clock genes(Bmal1,Per2,Rev -erba)in the cardiac myocytes.And the expressions pattern of Bmal1 and Per2 genes were in the opposite phase.While Bmal1 gene expres-sion appeared at peak at 12 h,Per2 gene expression appeared in a trough.Expression of Rev -erba gene trend began to rise at 8 h,and the highest expression level appeared at 12 -16 h.Conclusions 1a,25(OH)2 D3 can affect Bmal1, Per2 and Rev -erba mRNA expressions of circadian clock genes in the cardiac myocytes.

Protective function of tocilizumab in human cardiac myocytes ischemia reperfusion injury

Objective: To investigate the protective function of tocilizumab in human cardiac myocytes ischemia-reperfusion injury. Methods: The human cardiac myocytes were treated by tocilizumab with different concentrations(1.0 mg/mL, 3.0 mg/mL, 5.0 mg/mL) for 24 h, then cells were cultured in ischemia environment for 24 h and reperfusion environment for 1 h. The MTT and flow cytometry were used to detect the proliferation and apoptosis of human cardiac myocytes, respectively. The mRNA and protein expressions of Bcl-2 and Bax were measured by qRT-PCR and western blot, respectively. Results: Compared to the negative group, pretreated by tocilizumab could significantly enhance the proliferation viability and suppress apoptosis of human cardiac myocytes after suffering ischemia reperfusion injury (. P<0.05). The expression of Bcl-2 in tocilizumab treated group were higher than NC group (. P<0.05), while the Bax expression were lower (. P<0.05). Conclusions: Tocilizumab could significantly inhibit apoptosis and keep the proliferation viability of human cardiac myocytes after suffering ischemia reperfusion injury. Tocilizumab may obtain a widely application in the protection of ischemia reperfusion injury.

Purification of CT3 Fragment of Cav1.2 with Dithiothreitol / 中国医科大学学报

Objective To explore whether dithiothreitol(DTT)is helpful for PreScission Protease to cut off the GST from GST?CT3 protein. Meth?ods The pGEX?6P?3/CT3 recombinant plasmid was transfected into Escherichia coli BL21,and the GST?CT3 fusion protein was purified by B?PER method. PreScission Protease was applied with 10 mmol/L DTT to cut off the GST,then the SDS?PAGE was performed for identification of the CT3 protein. Results Without DTT,it was very difficult for PreScission Protease to cut off the GST from GST?CT3 protein. However,in the pres?ence of 10 mmol/L DTT,PreScission Protease could cut off the GST easily as identified by SDS?PAGE. Conclusion 10 mmol/L DTT can help Pre?Scission Protease to cut GST from GST?CT3 protein,so as to achieve high concentration of CT3.

Regulatory effects of long non-coding RNA HIF1A-AS1 on ischemic myocardial reperfusion injury in rats / 第二军医大学学报

Objective To study the regulatory effects of long non-coding RNA HIF1A-AS1 on the myocardial ischemia reperfusion (I/R) injury and the related mechanism. Methods Myocardial I/R injury model was established with SD rats, and hypoxia reoxygenation (H/R) model was established with rat cardiac myocytes. si-HIF1A-AS1 was used to inhibit HIF1A-AS1 expression in the cardiac myoctyes. Then the mRNA expression of HIF1A-AS1 was detected by real-time PCR, the growth vitality of cardiac myocytes was investigated by MTT assay, the concentration of lactate dehydrogenase (LDH) in the culture media was detected by ELISA, and the autophagy-associated protein Beclin-1 expression was observed by Western blotting analysis. Results HIF1A-AS1 expression was increased in cardiac muscle of rat I/R model and rat cardiac myocytes of H/R model. Inhibition of HIF1A-AS1 by siRNA protected the cardiomyocytes against H/R injuries, reversing the decreased growth vitality of cardiac myoctyes, increased LDH level in the culture media, and increased expression of autophagy-related protein Beclin-1 induced by H/R stimulation. Conclusion Inhibition of long non coding RNA HIF1A AS1 might play a protective role in I/R injury of cardiac myoctyes by inhibiting the excessive autophagy of cardiomyocytes.

Protective function of tocilizumab in human cardiac myocytes ischemia reperfusion injury

Objective:To investigate the protective function of tocilizumab in human cardiac myocytes ischemia-reperfusion injury.Methods:The human cardiac myocytes were treated by tocilizumab with different concentrations(1.0 mg/mL, 3.0 mg/mL, 5.0 mg/mL) for 24 h,then cells were cultured in ischemia environment for 24 h and reperfusion environment for 1 h. The MTT and flow cytometry were used to detect the proliferation and apoptosis of human cardiac myocytes, respectively. The mRNA and protein expressions of Bcl-2 and Bax were measured by qRT-PCR and western blot, respectively.Results:Compared to the negative group, pretreated by tocilizumab could significantly enhance the proliferation viability and suppress apoptosis of human cardiac myocytes after suffering ischemia reperfusion injury(P<0.05).The expression of Bcl-2 in tocilizumab treated group were higher thanNC group(P<0.05), while theBax expression were lower(P<0.05).Conclusions:Tocilizumab could significantly inhibit apoptosis and keep the proliferation viability of human cardiac myocytes after suffering ischemia reperfusion injury. Tocilizumab may obtain a widely application in the protection of ischemia reperfusion injury.

Isoflurane attenuates human cardiacmyocytes anoxia/reoxygenation injury / 基础医学与临床

Objective_To explore the effect and the mechanism of isoflurane on human cardiac myocytes ( HCM) injury induced by anoxia/reoxygenation ( AR) .Methods_HCM cells were divided into control group ( con) , an-oxia/reoxygenation group (AR) and isoflurane (0.5%, 1%, 1.5%and 2%) treatment group (n=6).Cell via-bility, LDH activity, apoptosis and the expression level of Anoxia inducible factor-1α( HIF-1α) were detected using CCK-8 assay, LDH activity assay kit, Annexin V-FITC/PI staining, PCR and western blot, respectively. Results_Compared with the con group, cell viability decreased, LDH activity and apoptosis cells increased in AR group.Isoflurane can significantly relieve the decrease of cell viability, the increase of LDH activity and apoptosis cells, and the down-regulation of the mRNA and protein expression level of HIF-1αinduced by AR ( P<0.05 ) . Compared with AR group, the mRNA and protein expression level of HIF-1αin siRNA transfected group signifi-cantly decreased (P<0.05).2%isoflurane significantly relieve the increase of cell viability, the decrease of LDH activity and apoptotic cells induced by HIF-siRNA in AR injuried HCM cells(P<0.05).Conclusions_Isoflurane can protect HCM cells from AR injury partly through up-regulate the expression of HIF-1α.

Protective function of tocilizumab in human cardiac myocytes ischemia reperfusion injury

OBJECTIVE@#To investigate the protective function of tocilizumab in human cardiac myocytes ischemia-reperfusion injury.@*METHODS@#The human cardiac myocytes were treated by tocilizumab with different concentrations(1.0 mg/mL, 3.0 mg/mL, 5.0 mg/mL) for 24 h, then cells were cultured in ischemia environment for 24 h and reperfusion environment for 1 h. The MTT and flow cytometry were used to detect the proliferation and apoptosis of human cardiac myocytes, respectively. The mRNA and protein expressions of Bcl-2 and Bax were measured by qRT-PCR and western blot, respectively.@*RESULTS@#Compared to the negative group, pretreated by tocilizumab could significantly enhance the proliferation viability and suppress apoptosis of human cardiac myocytes after suffering ischemia reperfusion injury (P<0.05). The expression of Bcl-2 in tocilizumab treated group were higher than NC group (P<0.05), while the Bax expression were lower (P<0.05).@*CONCLUSIONS@#Tocilizumab could significantly inhibit apoptosis and keep the proliferation viability of human cardiac myocytes after suffering ischemia reperfusion injury. Tocilizumab may obtain a widely application in the protection of ischemia reperfusion injury.

Role of the phosphocreatine system on energetic homeostasis in skeletal and cardiac muscles / Papel do sistema da fosfocreatina na homeostase energética das musculaturas esquelética e cardíaca

Adenosine triphosphate is the present energy currency in the body, and is used in various cellular and indispensable processes for the maintenance of cell homeostasis. The regeneration mechanisms of adenosine triphosphate, from the product of its hydrolysis – adenosine diphosphate – are therefore necessary. Phosphocreatine is known as its quickest form of regeneration, by means of the enzyme creatine kinase. Thus, the primary function of this system is to act as a temporal energy buffer. Nevertheless, over the years, several other functions were attributed to phosphocreatine. This occurs as various isoforms of creatine kinase isoforms have been identified with a distinct subcellular location and functionally coupled with the sites that generate and use energy, in the mitochondria and cytosol, respectively. The present study discussed the central and complex role that the phosphocreatine system performs in energy homeostasis in muscle cells, as well as its alterations in pathological conditions.

A adenosina trifosfato é a moeda corrente de energia no organismo, sendo utilizada em diversos processos celulares e indispensável para a manutenção da homeostase celular. Mecanismos de regeneração da adenosina trifosfato, a partir de seu produto de hidrólise – a adenosina difosfato – são, dessa forma, necessários. A fosfocreatina é conhecidamente sua fonte mais rápida de regeneração, por meio da enzima creatina quinase. Assim, a principal função desse sistema é atuar como um tampão temporal de energia. Entretanto, ao longo dos anos, diversas outras funções foram atribuídas à fosfocreatina. Isso ocorreu à medida que foram identificadas diversas isoformas da creatina quinase com localização subcelular distinta e acopladas de forma funcional aos sítios geradores e utilizadores de energia, na mitocôndria e citosol, respectivamente. O presente trabalho discutiu o papel central e complexo que o sistema da fosfocreatina desempenha na homeostase energética nas células musculares, bem como suas alterações em quadros patológicos.

Anti-apoptotic effect of NGF on H9 c2 cardiac myocytes in a hypoxia/reoxygenation injury model / 中国药理学通报

Aim To investigate the anti-apoptotic effect of NGF on H9 c2 cardiac myocytes in a hypoxia / reox-ygenation injury model and its mechanism. Methods The H9 c2 cardiac myocytes were randomly divided into five groups:control group ( C group) , hypoxia/reoxy-genation group ( H/R group) , NGF group ( N group) , NGF+LY294002 group ( N+L group) and LY294002 group( L group) . Each group received the correspond-ing treatment. Cell survival rate was tested by cell counter kit-8 methods. Apoptotic rate was evaluated by propidium iodide ( PI ) staining and flow cytometry (FCM). The levels of Caspase-12, p-Akt/Akt were e-valuated by Western blot. Results The NGF group could significantly protect the H9 c2 cardiac myocytes under the hypoxia / reoxygenation injury with increased cell survival rate. It also decreased the apoptotic per-centage, upregulated the level of p-Akt/Akt and inhib-ited the expression of Caspase-12 . As the specific in-hibitor of PI3k receptor, LY294002 decreased the level of p-Akt. Conclusion NGF has the effect of anti-ap-optosis on H9 c2 cardiac myocytes exposed to hypoxia /reoxygenation injury via PI3k-Akt signal pathway.

Effect of CrkL silence on hypoxia/reoxygenation-induced apoptosis and survival inhibition in cardiomyocytes and the underlying mechanisms / 第二军医大学学报

Objective: To investigate the effect of CrkL silence on hypoxia/reoxygenation (H/R)-induced apoptosis and survival inhibition in cardiomyocytes and the underlying mechanisms. Methods: H9C2 cardiomyocytes were infected with blank, negative lentivirus and CrkL RNAi lentivirus (CrkL mRNA silence), and then treated with H/R separately. The cardiomyocytes were divided into blank group, negative lentivirus group, CrkL silence group, blank + H/R group, negative lentivirus + H/R group and CrkL silence + H/R group. The expression of CrkL mRNA was detected by RT-PCR, and the expression of CrkL and p-ERK1/2 protein was detected by Western blotting analysis. The apoptosis rate of cardiomyocytes was analyzed by flow cytometry, and the cell proliferation rate was analyzed by MTT. Results: Compared with blank and negative lentivirus groups, CrkL silence group had significantly decreased CrkL mRNA and protein, p-ERK1 protein, p-ERK1/2 protein and proliferation rate (P<0.05 or P<0.01), and significantly increased apoptosis rate (P<0.01). The same was true for CrkL silence + H/R group when compared with the blank + H/R and negative lentivirus + H/R groups. Conclusion: CrkL silence can aggravate H/R-induced apoptosis and survival inhibition in cardiomyocytes, which might be mediated by the decrease of p-ERK1/2 protein expression.