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Myocardial ischemia-reperfusion injury （MIRI） is a serious complication of revascularization in patients with myocardial infarction. The nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） signaling pathway plays an important role in the pathological process of MIRI. Currently，research has found that traditional Chinese medicine has a good effect on myocardial injury caused by ischemia-reperfusion. Based on the Nrf2/HO-1 signaling pathway，this article summarizes the action mechanism of traditional Chinese medicine formulas and monomers in intervening with MIRI. It is found that traditional Chinese medicine formulas （Yixin formula，Wenyang tongmai formula，Dingxin formula Ⅰ），monomers such as terpenoids （ginkgolides， astragaloside Ⅳ，ginsenosides），phenols （brazilin，hematoxylin A，resveratrol） and quinones （aloe，emodin） can alleviate MIRI by activating the Nrf2/HO-1 signaling pathway，inhibiting oxidative stress and inflammatory reactions，etc.
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Abstract This study aimed to investigate the role and signaling pathways of β3-AR in myocardial ischemia/reperfusion (I/R) injury, which is one of the leading causes of death worldwide. 47 male rats were randomly divided into two main groups to evaluate infarct size and molecular parameters. Rats in both groups were randomly divided into 4 groups. Control (sham), I/R (30 min ischemia/120 min reperfusion), BRL37344 (BRL) (A) (5 µg/kg single-dose pre-treatment (preT) before I/R) and BRL (B) (5 µg/kg/day preT for 10 days before I/R). Infarct size was determined with triphenyltetrazolium chloride staining and analyzed with ImageJ program. The levels of AMPK, SIRT1, mTOR, and p70SK6 responsible for cellular energy and autophagy were evaluated by western blot. Infarct size increased in the I/R group (44.84 ± 1.47%) and reduced in the single-dose and 10-day BRL-treated groups (32.22 ± 1.57%, 29.65 ± 0.55%; respectively). AMPK and SIRT1 levels were decreased by I/R but improved in the treatment groups. While mTOR and p70S6K levels increased in the I/R group, they decreased with BRL preT. BRL preT protects the heart against I/R injury. These beneficial effects are mediated in part by activation of AMPK and SIRT1, inhibition of mTOR and p70S6K, and consequently protected autophagy.
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Total flavonoids of Dracocephalum moldavica L. (TFDM) is an effective component extracted and isolated from the traditional Uighur medicinal herb Cymbidium fragrans. Cymbidium fragrans has the effects of tonifying the heart and brain, promoting blood circulation and resolving blood stasis, and has been widely used in the treatment of cardiovascular and cerebrovascular diseases for a long time. The purpose of this study was to determine the effect of total flavonoids from Cymbidium fragrans on hypoxia/re-oxygenation (H/R) injury in H9c2 (rat cardiomyocytes) cells and its mechanism. A model (H/R) of hypoxia/re-oxygenation injury in H9c2 cells was established using hypoxia and glucose deprivation for 9 h combined with re-oxygenation and rehydration for 2 h to simulate myocardial ischemia-reperfusion injury. The effects of total flavonoids from Cymbidium fragrans on cell viability, markers of myocardial cell damage, oxidative stress levels, and reactive oxygen radical (ROS) content were investigated, Western blot was used to detect the expression of vascular endothelial growth factor B (VEGF-B) and adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway related proteins. The results showed that the total flavonoids of Cymbidium fragrans significantly increased the viability of myocardial cells after H/R injury, and decreased the content of lactate dehydrogenase (LDH) and creatine kinase isozyme (CK-MB) in the cell supernatant. It significantly reduced malondialdehyde (MDA), increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, and decreased intracellular ROS and nitric oxide (NO) content. Western blot analysis showed that the total flavonoids of Cymbidium fragrans decreased Bax levels in H9c2 cells damaged by H/R and increased Bcl-2 expression. Total flavones of Cymbidium fragrans upregulate VEGF-B/AMPK pathway related proteins VEGF-B, vascular endothelial growth factor receptor 1 (VEGFR-1), neuropilin 1 (NRP-1), peroxisome-proliferator-activated receptor γ coactivator-1α (PGC-1α), phosphorylated adenosine monophosphate activated protein (p-AMPK) and phospho mechanistic target of rapamycin (p-MTOR) levels. The above research results indicate that the total flavonoids of Cymbidium can significantly reduce the H/R injury of myocardial cells, which may be related to the upregulation of VEGF-B/AMPK pathway and inhibition of oxidative stress response.
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OBJECTIVE@#To observe the effects of electroacupuncture (EA) pretreatment on cardiac function, sympathetic nerve activity, indexes of myocardial injury and GABAA receptor in fastigial nucleus in rats with myocardial ischemia reperfusion injury (MIRI), and to explore the neuroregulatory mechanism of EA pretreatment in improving MIRI.@*METHODS@#A total of 60 male SD rats were randomly divided into a sham operation group, a model group, an EA group, an agonist group and an agonist+EA group, 12 rats in each group. The MIRI model was established by ligation of the left anterior descending coronary artery. EA was applied at bilateral "Shenmen" (HT 7) and "Tongli" (HT 5) in the EA group and the agonist+EA group, with continuous wave, in frequency of 2 Hz and intensity of 1 mA, 30 min each time, once a day for 7 consecutive days. After intervention, the MIRI model was established. In the agonist group, the muscone (agonist of GABAA receptor, 1 g/L) was injected in fastigial nucleus for 7 consecutive days before modeling, 150 μL each time, once a day. In the agonist+EA group, the muscone was injected in fastigial nucleus 30 min before EA intervention. The data of electrocardiogram was collected by PowerLab standard Ⅱ lead, and ST segment displacement and heart rate variability (HRV) were analyzed; the serum levels of norepinephrine (NE), creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) were detected by ELISA; the myocardial infarction area was measured by TTC staining; the morphology of myocardial tissue was observed by HE staining; the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were detected by immunohistochemistry and real-time PCR.@*RESULTS@#Compared with the sham operation group, in the model group, ST segment displacement and ratio of low frequency to high frequency (LF/HF) of HRV were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber was broken and interstitial edema was serious, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01). Compared with the model group, in the EA group, ST segment displacement and LF/HF ratio were decreased (P<0.01), HRV frequency domain analysis showed reduced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were decreased (P<0.01), the percentage of myocardial infarction area was decreased (P<0.01), myocardial fiber breakage and interstitial edema were lightened, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were decreased (P<0.01). Compared with the EA group, in the agonist group and the agonist+EA group, ST segment displacement and LF/HF ratio were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber breakage and interstitial edema were aggravated, the positive expression and mRNA expression of GABAA receptor in fastigial nucleus were increased (P<0.01).@*CONCLUSION@#EA pretreatment can improve the myocardial injury in MIRI rats, and its mechanism may be related to the inhibition of GABAA receptor expression in fastigial nucleus, thereby down-regulating the excitability of sympathetic nerve.
Subject(s)
Male , Animals , Rats , Rats, Sprague-Dawley , Cerebellar Nuclei , Electroacupuncture , Myocardial Reperfusion Injury/therapy , Receptors, GABA-A/genetics , RNA, MessengerABSTRACT
Due to its high incidence and mortality rate， acute myocardial infarction poses a serious threat to public health. Reperfusion therapy is the preferred treatment strategy for acute myocardial infarction， which can quickly restore blood circulation to the ischemic myocardium， rescue dying myocardial cells， reduce infarct size， and lower the mortality rate. However， reperfusion may lead to additional heart damage， known as myocardial ischemia-reperfusion injury （MIRI）. Therefore， how to alleviate MIRI has become one of the urgent issues in cardiovascular therapy. Traditional Chinese medicine （TCM） has the advantage of multiple components， multiple pathways， and multiple targets in the treatment of MIRI， providing new ideas for reducing MIRI. Adenosine 5'-monophosphate （AMP）-activated protein kinase （AMPK） is closely related to MIRI， and it plays an important role in alleviating MIRI by regulating inflammation， oxidative stress， autophagy， apoptosis， and ferroptosis. This article reviewed the basic structure of the AMPK signaling pathway and its role in MIRI， as well as the research progress of TCM in the treatment of MIRI by regulating the AMPK pathway， aiming to provide a theoretical basis for the prevention and treatment of MIRI.
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OBJECTIVE To investigate the effects of astilbin （AST） on myocardial ischemia-reperfusion injury （MIRI） in rats and its potential mechanism. METHODS SD male rats were randomly divided into sham operation group， model group， positive control group （Compound Salvia miltiorrhiza tablets， 240 mg/kg）， AST low-dose and high-dose groups （30， 90 mg/kg）， and high- dose of AST+hypoxia-inducible factor-1α（HIF-1α） inhibitor group （AST 90 mg/kg+2ME2 15 mg/kg）， with 25 rats in each group. Except for sham operation group， MIRI model was induced in other groups， and then given relevant drug or normal saline intragastrically or intraperitoneally， for consecutive 28 d. Serum contents of cardiac troponin I （cTnI） and creatine kinase isoenzyme （CK-MB） were detected； volume ratio of myocardial infarction was measured； the pathological changes of myocardium， the apoptotic rate of myocardial cells and ultrastructure of mitochondria in myocardial tissue were all observed. The contents of tumor necrosis factor α （TNF-α）， interleukin 6 （IL-6） and malondialdehyde （MDA）， the activity of superoxide dismutase （SOD）， the expressions of HIF-1α， adenovirus E1B interacting protein 3 （BNIP3） and myosin-like Bcl-2 interacting protein （Beclin1） were determined in myocardium. The ratio of microtubule-associated protein light chain 3 （LC3） Ⅱ to Ⅰ （LC3 Ⅱ/Ⅰ） in rat myocardium was calculated. RESULTS Compared with model group， no obvious swelling was found in the myocardial tissue of rats in positive control group， AST low-dose and high-dose groups， and the myocardial fibers were arranged regularly； the volume ratio of myocardial infarction， the contents of cTnI， CK-MB， TNF-α， IL-6 and MDA， the apoptotic rate were decreased significantly （P＜0.05）， while SOD activity， protein expressions of HIF-1α， BNIP3 and Beclin1， LC3Ⅱ/Ⅰ were increased significantly （P＜0.05）. HIF-1α inhibitor could significantly weaken the improvement effect of AST on the above indicators in MIRI model rats （P＜0.05）. CONCLUSIONS AST enhances mitochondrial autophagy by activating HIF-1α/BNIP3 signaling pathway， thereby reducing MIRI in rats.
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Coronary microcirculation disorder after myocardial ischemia reperfusion （MIR） is a prominent problem in the treatment of coronary heart disease. According to the physiological commonality between “collaterals-sweat pore qi and fluid” and coronary microcirculation， and the evolution of the course of MIR， it is believed that “heart collateral stasis obstruction， sweat pore constraint and block” is the cause of coronary microcirculation disorder. The evolution of the pathogenesis can be divided into three periods. During the myocardial ischemia period， the pathogenesis is heart collaterals obstruction and sweat pores empty， while during the ischemia reperfusion period， it is internal formulation of deficiency wind， spasms of collaterals or slight heart collaterals obstruction； in the coronary microcirculation disorder period， sweat pores constraint and block， constraint transforming into heat， qi and fluid failing to diffuse are the pathogenesis. The corresponding treatment principle is assisting dredge with supplementation， and supplementing deficiency to dispel stasis； treating wind and blood simultaneously， and extinguishing wind to arrest convulsion； clearing heat and cooling blood， and diffusing qi and unblocking qi and fluid. Moreover， it is recommended to treat the heart and lungs simultaneously， and regulate the heart and liver at the same time.
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Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury (MIRI). Moderate mitophagy can remove damaged mitochondria, inhibit excessive reactive oxygen species accumulation, and protect mitochondria from damage. However, excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival, and aggravates cell death. How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane, which mainly include phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced kinase 1/Parkin, hypoxia-inducible factor-1 α/Bcl-2 and adenovirus e1b19k Da interacting protein 3, FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on. In this review, the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI, and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine, thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.
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Humans , Mitochondria/metabolism , Mitophagy/genetics , Myocardial Reperfusion Injury , Protein Kinases/metabolismABSTRACT
Acute myocardial infarction seriously endangers the health of people due to its high morbidity and high mortality. Reperfusion strategy is the preferred treatment strategy for acute myocardial infarction. However, reperfusion may lead to additional heart damage, namely myocardial ischemia reperfusion injury(MIRI). Therefore, how to reduce myocardial ischemia reperfusion injury has become one of the urgent problems to be solved in cardiovascular disease. Traditional Chinese medicine(TCM) has the multi-component, multi-channel, and multi-target advantages in the treatment of MIRI, which offers new ideas in this aspect. TCM containing flavonoids has a variety of biological activities and plays a significant role in the treatment of MIRI, which has great research and development application value. TCM containing flavonoids can regulate multiple signaling pathways of MIRI, such as phosphatidylinositol 3 kinase/kinase B(PI3K/Akt) signaling pathway, Janus kinase/signal transducer and activator of transcriptions(JAK/STAT) signaling pathway, adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK) signaling pathway, mitogen-activated protein kinase(MAPK) signaling pathway, nuclear factor-erythroid 2-related factor 2/antioxidant response element(Nrf2/ARE) signaling pathway, nuclear factor kappa-B(NF-κB) signaling pathway, silent information regulator 1(Sirt1) signaling pathway, and Notch signaling pathway. It reduces MIRI by inhibiting calcium overload, improving energy metabolism, regulating autophagy, and inhibiting ferroptosis and apoptosis. Therefore, a review has been made based on the regulation of relative signaling pathways against MIRI by TCM containing flavonoids, thus providing theoretical support and potential therapeutic strategies for TCM to alleviate MIRI.
Subject(s)
Humans , Myocardial Reperfusion Injury , Phosphatidylinositol 3-Kinases , Signal Transduction , NF-kappa B , AMP-Activated Protein Kinases , FlavonoidsABSTRACT
This study aimed to parallelly investigate the cardioprotective activity of Cinnamomi Ramulus formula granules(CRFG) and Cinnamomi Cortex formula granules(CCFG) against acute myocardial ischemia/reperfusion injury(MI/RI) and the underlying mechanism based on the efficacy of "warming and coordinating the heart Yang". Ninety male SD rats were randomly divided into a sham group, a model group, CRFG low and high-dose(0.5 and 1.0 g·kg~(-1)) groups, and CCFG low and high-dose(0.5 and 1.0 g·kg~(-1)) groups, with 15 rats in each group. The sham group and the model group were given equal volumes of normal saline by gavage. Before modeling, the drug was given by gavage once a day for 7 consecutive days. One hour after the last administration, the MI/RI rat model was established by ligating the left anterior descending artery(LAD) for 30 min ischemia followed by 2 h reperfusion except the sham group. The sham group underwent the same procedures without LAD ligation. Heart function, cardiac infarct size, cardiac patho-logy, cardiomyocyte apoptosis, cardiac injury enzymes, and inflammatory cytokines were determined to assess the protective effects of CRFG and CCFG against MI/RI. The gene expression levels of nucleotide-binding oligomerization domain-like receptor family pyrin domain protein 3(NLRP3) inflammasome, apoptosis-associated speck-like protein containing a CARD(ASC), cysteinyl aspartate specific proteinase-1(caspase-1), Gasdermin-D(GSDMD), interleukin-1β(IL-1β), and interleukin-18(IL-18) were determined by real-time quantitative polymerase chain reaction(RT-PCR). The protein expression levels of NLRP3, caspase-1, GSDMD, and N-GSDMD were determined by Western blot. The results showed that both CRFG and CCFG pretreatments significantly improved cardiac function, decreased the cardiac infarct size, inhibited cardiomyocyte apoptosis, and reduced the content of lactic dehydrogenase(LDH), creatine kinase MB isoenzyme(CK-MB), aspartate transaminase(AST), and cardiac troponin Ⅰ(cTnⅠ). In addition, CRFG and CCFG pretreatments significantly decreased the levels of IL-1β, IL-6, and tumor necrosis factor-α(TNF-α) in serum. RT-PCR results showed that CRFG and CCFG pretreatment down-regulated the mRNA expression levels of NLRP3, caspase-1, ASC, and downstream pyroptosis-related effector substances including GSDMD, IL-18, and IL-1β in cardiac tissues. Western blot revealed that CRFG and CCFG pretreatments significantly decreased the protein expression levels of NLRP3, caspase-1, GSDMD, and N-GSDMD in cardiac tissues. In conclusion, CRFG and CCFG pretreatments have obvious cardioprotective effects on MI/RI in rats, and the under-lying mechanism may be related to the inhibition of NLRP3/caspase-1/GSDMD signaling pathway to reduce the cardiac inflammatory response.
Subject(s)
Male , Animals , Rats , Rats, Sprague-Dawley , Interleukin-18 , Myocardial Reperfusion Injury , NLR Family, Pyrin Domain-Containing 3 Protein , Tumor Necrosis Factor-alpha , Myocardial Infarction , Caspase 1ABSTRACT
ABSTRACT Introduction: The objective of this study is to investigate the protective mechanism of dexmedetomidine (Dex) in myocardial ischemia/reperfusion (MIR)-induced acute lung injury (ALI) of diabetic rats by inhibiting hypoxia-inducible factor-1α (HIF-1α). Methods: Initially, healthy male Sprague Dawley rats were treated with streptozocin to induce diabetes. Then, three weeks after the induction, Dex or lentiviral vector (LV)-HIF-1α was injected into the rats 30 minutes prior to the MIR modeling. After four weeks, lung tissues were harvested for pathological changes observation and the wet/dry weight (W/D) ratio determination. Afterwards, oxidative stress indicators and pro-inflammatory factors were measured. In addition, HIF-1α expression was assessed by immunohistochemistry and western blot analysis. Results: Dex could suppress inflammatory cell infiltration, improve lung tissue structure, reduce pathological score and the W/D ratio, and block oxidative stress and inflammatory response in MIR-induced ALI of diabetic rats. Besides, Dex could also inhibit HIF-1α expression. Moreover, Dex + LV-HIF-1α reversed the protective role of Dex on diabetic MIR-induced ALI. Conclusion: Our study has made it clear that Dex inhibited the upregulation of HIF-1α in diabetic MIR-induced ALI, and thus protect lung functions by quenching the accumulation of oxygen radical and reducing lung inflammatory response.
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@#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 ×109/L vs. 6.41±0.72 ×109/L, P<0.05; N: 9.27±4.75 ×109/L vs. 3.89±0.81 ×109/ 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.
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Objective:To explore the regulatory effect of cellular FLICE-like inhibitory protein (cFLIP) on myocardial ischemia-reperfusion injury based on the RIPK1/RIPK3/MLKL-mediated necroptosis pathway.Methods:The cardiomyocyte hypoxia/reoxygenation (H/R) model was constructed by hypoxia for 4 h/reoxygenation for 12 h, and the rat ischemia reperfusion (I/R) model was constructed by ligating the left anterior descending artery for 30 min and reperfusion for 3 h. CCK-8 method was used to detect the viability of cardiomyocytes in each group. DAPI/PI double staining was used to observe changes in necrosis rate of myocardial cell. STRING database was used to predict the protein interaction network of cFLIP. TTC staining was used to detect the area of myocardial infarction in each group of rats, and the protein expression of cFLIPL, cFLIPS, p-RIPK1, p-RIPK3 and p-MLKL were detected by Western blot.Results:In cardiomyocyte H/R injury and myocardial tissue I/R injury, the protein expressions of cFLIPL and cFLIPS were significantly down-regulated, while the levels of p-RIPK1, p-RIPK3 and p-MLKL were increased significantly. Up-regulating the protein expression of cFLIPL and cFLIPS could significantly reduce the damage of cardiomyocytes and the rate of cell necrosis induced by H/R, and decrease the area of myocardial infarction caused by I/R. STRING database results showed that cFLIP had direct protein interactions with RIPK1 and RIPK3. Overexpression of cFLIP in cardiomyocyte and myocardial tissue significantly inhibited H/R or I/R induced the phosphorylation levels of RIPK1, RIPK3 and MLKL.Conclusions:Overexpression of cFLIP can significantly inhibit the RIPK1/RIPK3/MLKL-mediated necroptosis, thereby reducing myocardial cell damage and decreasing the area of myocardial infarction.
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Objective:To evaluate the effect of gabapentin on myocardial ischemia-reperfusion injury and its mechanism.Methods:Sixty male clean SD rats, aged 10 weeks and weighing 250 g~300 g, were divided into 5 groups ( n=12) with 12 rats in each group by random number table method: Sham group, myocardial ischemia reperfusion group (group I/R), gabapentin group (group Gap), LY294002 group (group LY) and gabapentin +LY294002 group (group Gap +LY). The model of myocardial ischemia reperfusion injury was established by ligation of the left anterior descending coronary artery for 30 min and reperfusion for 120 min. Heart rate (HR), mean arterial pressure (MAP) and the rate pressure product (RPP) were recorded at baseline before ischemia (T 0) for 30 min (T 1) and reperfusion for 120 min (T 2) to evaluate hemodynamic changes during ischemia and reperfusion; The frequency of PVCs and VT/VF were recorded to evaluate the occurrence of arrhythmias during ischemia/reperfusion. TTC staining was used to detect myocardial infarction area. And the protein expression levels of PI3K and Akt in myocardial tissue were detected by Western blotting. Results:Compared with group I/R, the myocardial infarction area, PVCs and VT/VF times, and the protein expression levels of PI3K and p-Akt were significantly increased in group Gap ( P<0.05). Compared with group Gap, the area of myocardial infarction, the number of PVCs and VT/VF, and the protein expression of PI3K and p-Akt were significantly decreased in the group Gap +LY ( P<0.05). Conclusions:Gabapentin can alleviate myocardial ischemia-reperfusion injury, and its mechanism is related to the activation of PI3K-AKT signaling pathway.
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Objective:To investigate the dynamic changes of mitochondrial fission and fusion in the heart of cardiac arrest (CA) rats after return of spontaneous circulation (ROSC), and to explore the role of mitochondrial fission and fusion in the myocardial injury after ROSC.Methods:Healthy male SD rats were randomly random number assigned into the post-resuscitation (PR) 4 h ( n=12), PR 24 h ( n=12), PR 72 h ( n=12), and sham groups ( n=6). The rat CA model was induced by asphyxia, and cardiopulmonary resuscitation (CPR) was performed 6 min after CA. The protein expressions of mitochondrial Drp1, Fis1, Mfn1, and Opa1 were determined by Western blot in each group at 4, 24 and 72 h after ROSC. The mRNA expressions of Drp1, Fis1, Mfn1, and Opa1 were determined by RT-PCR. Myocardial ATP content and mitochondrial respiratory function were measured. The histopathologic changes of myocardial tissue were observed under light microscope. One-way analysis of variance (ANOVA) was use to compare quantitative data, and LSD- t test was used for comparison between groups. Results:Compared with the sham group, the protein and mRNA expressions of Drp1 and Fis1 were increased (all P<0.05) and the protein and mRNA expressions of Mfn1 and Opa1 were decreased (all P<0.05) in the PR 4 h and PR 24 h groups. However, there were no statistical differences in the protein and mRNA expressions of Drp1, Fis1, Mfn1, and Opa1 in the PR 72 h group compared with the sham group (all P>0.05). Compared with the sham group, the levels of ATP content [(4.53±0.76) nmol/g protein vs. (8.57±0.44) nmol/g protein and (5.58±0.58) nmol/g protein vs. (8.57±0.44) nmol/g protein] and mitochondrial respiratory control rate [(2.47±0.38) vs. (3.45±0.32) and (2.97±0.24) vs. (3.45±0.32)] were obviously decreased in the PR 4 h and PR 24 h groups (all P<0.05). There were no statistically significant differences in the ATP content [(7.73±0.95) nmol/g protein vs. (8.57±0.44) nmol/g protein] and mitochondrial respiratory control ratio [(3.39±0.34) vs. (3.45±0.32)] between the PR 72 h group and the sham group (all P>0.05). The pathological damage of myocardial tissue was obvious in the PR 4 h group, and was improved significantly in the PR 72 h group. Conclusions:The imbalance of mitochondrial fission and fusion is probably involved in the pathological process of myocardial injury after ROSC, which may be related to mitochondrial dysfunction.
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Cardiovascular diseases cause significant morbidity and mortality worldwide, incurring a major public health burden. Gastrodia elata Blume is a traditional Chinese herbal medicine that has been widely used to treat central nervous system and cardiovascular diseases. Gastrodin, as the major active component in Gastrodia elata Blume, can confer protection against cardiovascular diseases. In this review, we summarize the anti-inflammatory actions, anti-cardiac hypertrophy, anti-hypertension, anti-atherosclerosis, and angiogenic effects of gastrodin, as well as its protective effects on vascular cells and against myocardial ischemia-reperfusion injury. The medical potential of gastrodin in diabetes-related cardiovascular diseases is also discussed.
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Objective:To explore the effects of calcium/calmodulin dependent protein kinase II (CaMKII) on myocardial ischemia-reperfusion injury in vitro, and apoptosis and autophagy of myocardial cells in isolated rats.Methods:Seventy female SD rats (250-280 g) with normal electrocardiogram were selected to establish the myocardial IR injury model by Langendorff perfusion system. These SD rats were randomly divided into five groups (n=14): cardiac ischemia reperfusion group (IR group), CaMKII phosphorylation activator group (IR+ isoproterenol group), CaMKII phosphorylation inhibitor analogue group (IR+KN92 group), CaMKII phosphorylation inhibitor group (IR+KN93 group), and control group. After reperfusion, the left ventricular function and myocardial morphology were measured to assess the myocardial injury, and TUNEL was performed to assess the apoptosis index. Western blot was used to determine the phosphorylation levels of CaMKII and PLN (p-CaMKII/CaMKII and p-PLN/PLN), and the expression levels of apoptosis-related proteins Bax, Bcl-2, cleaved caspase-3, and autophagy marker proteins LC3II/LC3I, Beclin-1 and P62.Results:Compared with the control group, the left ventricular function of the IR group was decreased, morphological arrangement of myocardial fibers was disordered, and the apoptosis index was increased. The levels of p-CaMKII/CaMKII, p-PLN/PLN, cleaved caspase-3, Bax/Bcl-2, LC3II/LC3I, and Beclin-1 were increased significantly, while the level of P62 was decreased significantly, and apoptosis and autophagy were increased significantly (all P<0.05). Compared with the IR group, the myocardial damage of rats in the IR+KN93 group was significantly improved, the apoptosis index was decreased, and the expression of p-CaMKII/CaMKII, p-PLN/PLN, Cleaved Caspase-3, Bax/Bcl-2, LC3II/LC3I and Beclin-1 were significantly decreased and the level of p62 was remarkable increased, and apoptosis and autophagy decreased significantly (all P< 0.05). Compared with the IR group, the left ventricular function was further decreased in the IR+ isoproterenol group, while the levels of apoptosis and autophagy were further increased ( P < 0.05), while there was no significant difference in myocardial indexes between the IR+ KN92 group and the IR group ( P > 0.05). Conclusions:Inhibition of CaMKII phosphorylation attenuates isolated myocardial ischemia-reperfusion injury by reducing apoptosis and autophagy.
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OBJECTIVE@#To explore the role of salt-inducible kinase 2 (SIK2) in myocardial ischemia-reperfusion (IR) injury in rats.@*METHODS@#Fifteen male SD rats were randomized equally into sham operation group, myocardial IR model group, and SIK2 inhibitor group (in which the rats were treated with intravenous injection of 10 mg/kg bosutinib via the left femoral vein 24 h before modeling). Ultrasound was used to detect the cardiac function of the rats, and myocardial pathologies were observed with HE staining. Transmission electron microscopy was used to observe autophagy of myocardial cells, and Western blotting was performed to detect the contents of the autophagy-related proteins SIK2, LC3B, Beclin-1, p62 and the expressions of p-mTOR, mTOR, p-ULK1, and ULK1 in myocardial tissue.@*RESULTS@#Myocardial IR injury significantly increased the number of autophagosomes (P < 0.05) and the expression of SIK2 protein (P < 0.01) in the myocardial tissues. Treatment with bosutinib before modeling obviously lowered the expression of SIK2 protein (P < 0.01), alleviated myocardial pathologies, and reduced the number of autophagosomes (P < 0.05) in the myocardial tissue. The rats with myocardial IR injury showed obviously lowered LVEF and FS values (P < 0.001), which were significantly improved by bosutinib treatment (P < 0.05); no significant difference was detected in IVSDd or LVPWDd among the 3 groups (P > 0.05). Myocardial IR injury obviously increased the expressions of LC3-II/LC3-I and Beclin-1 proteins and lowered the expression of p62 protein (P < 0.01), and these changes were significantly rescued by bosutinib treatment (P < 0.05). The rat models of myocardial IR injury showed significantly increased expression of p-ULK1 (Ser757) (P < 0.01) and lowered expression of p-mTOR protein (P < 0.0001) in the myocardium, and these changes were obviously reversed by bosutinib (P < 0.01 or 0.05); there was no significant difference in mTOR and ULK1 expressions among the 3 groups (P > 0.05).@*CONCLUSION@#SIK2 may promote autophagy through the mTOR/ULK1 signaling pathway, and inhibiting SIK2 can reduce abnormal autophagy and alleviate myocardial IR injury in rats.
Subject(s)
Animals , Male , Rats , Autophagy , Autophagy-Related Protein-1 Homolog/metabolism , Beclin-1/metabolism , Down-Regulation , Myocardial Reperfusion Injury , Protein Serine-Threonine Kinases , Rats, Sprague-Dawley , Signal Transduction , TOR Serine-Threonine Kinases/metabolismABSTRACT
ObjectiveTo reveal the effect of Wenxin prescription on mitochondrial energy metabolism and silent information regulator 1 （SIRT1）/peroxisome proliferator-activated receptor-γ coactivator-1α （PGC-1α）/recombinant estrogen-related receptor α （ERRα） signaling pathway in rats with myocardial ischemia-reperfusion injury. MethodTotally 90 male Wistar rats of SPF grade were randomly assigned into a sham operation group， a model group， and low-， medium-， and high-dose Wenxin prescription groups， with 18 rats in each group. The rats in low-， medium-， and high-dose Wenxin prescription groups were administrated with 0.99， 1.98， and 3.96 g·kg-1 granules by gavage， respectively， and those in the sham operation group and model group with the same amount of normal saline. Twenty-one days after pre-administration， the rat model of myocardial ischemia-reperfusion injury was established by ligation of the left anterior descending coronary artery for 30 min and reperfusion for 2 h， and the rats in the sham operation group were only threaded without ligation. Myocardial infarction area was observed through 2，3，5-triphenyl-2h-tetrazolium chloride （TTC） staining， and the myocardial histopathology through hematoxylin-eosin （HE） staining. The levels of creatine kinase-MB （CK-MB） and lactate dehydrogenase （LDH） in serum， cytochrome C oxidase （CCO） and succinate dehydrogenase （SDH） in mitochondrion， and ATP in myocardial tissue were detected according to kit instructions. The mRNA and protein levels of SIRT1， PGC-1α， ERRα， and mitochondrial transcription factor A （TFAM） in myocardial tissue were determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the sham operation group， the model group showed broken and disordered myocardial fibers， cytoplasmic edema， and pyknosis and deviation of nuclei. Moreover， the modeling increased the levels of CK-MB and LDH （P<0.05， P<0.01）， lowered the levels of ATP， CCO， and SDH （P<0.05， P<0.01）， and down-regulated the mRNA and protein levels of SIRT1， PGC-1α， ERRα， and TFAM in myocardial tissue （P<0.05， P<0.01）. Compared with the model group， Wenxin prescription reduced the myocardial infarction area （especially in the high-dose group， P<0.01）， restored the pathological changes， lowered the levels of CK-MB and LDH （P<0.05， P<0.01）， increased the levels of ATP， CCO， and SDH （especially in the high-dose group， P<0.01）， and up-regulated the mRNA and protein levels of SIRT1， PGC-1α， ERRα， and TFAM in myocardial tissue （P<0.05， P<0.01）. ConclusionWenxin prescription can protect rats from myocardial ischemia-reperfusion injury by regulating myocardial mitochondrial energy metabolism via the SIRT1/PGC-1α/ERRα signaling pathway.
ABSTRACT
ObjectiveTo explore the mechanism of Wutou Chishizhi Wan in regulating autophagy and phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/glycogen synthase kinase-3β （GSK-3β） signaling pathway in rats with myocardial ischemia-reperfusion injury （MIRI）. MethodSixty male SD rats were randomly assigned into the normal group （normal saline）， model group （normal saline）， positive control （trimetazidine， 5.4 mg·kg-1） group， and low-， medium-， and high-dose （1.63， 4.9， 14.7 g·kg-1， respectively） Wutou Chishizhi Wan groups， with 10 rats in each group. The rats in other groups except the normal group underwent left anterior descending coronary artery ligation for modeling. Electrocardiogram was employed to detect the ST-segment elevation to evaluate the modeling. Hematoxylin-eosin （HE） staining was performed to reveal the damage of myocardial tissue. The levels of aspartate aminotransferase （AST） and creatine kinase （CK） were determined by colorimetry， and those of cardiac troponin T （cTnT） and myoglobin （MYO） by enzyme-linked immunosorbent assay （ELISA）. Western blot was carried out to determine the protein levels of microtubule-associated proteins 1 light chain 3 （LC3）， autophagy-related gene Beclin-1， PI3K， Akt， GSK-3β， p-GSK-3β， and p-Akt. ResultCompared with the normal group， the modeling elevated the serum levels of AST， CK， cTnT， and MYO （P<0.01）， destroyed the arrangement of myocardial cells abd nucle， twisted and broken myocardial fibers， up-regulated the protein levels of LC3Ⅱ/Ⅰ and Beclin-1 （P<0.01）， and down-regulated the protein levels of PI3K， p-Akt， and p-GSK-3β （P<0.01）. Compared with the model group， trimetazidine and Wutou Chishizhi Wan （all the doses） lowered the levels of AST， CK， cTnT， and MYO in serum （P<0.01）， restored the arrangement of myocardial cells and muscle fibers， reduced necrosis， down-regulated the protein level of Beclin-1 （P<0.01）， and up-regulated the protein levels of PI3K， p-Akt， and p-GSK-3β （P<0.01）. Additionally， Wutou Chishizhi Wan （all the doses） down-regulated the protein level of LC3Ⅱ/Ⅰ （P<0.05， P<0.01）. Compared with those in the trimetazidine group， the serum AST level rose in the low-dose Wutou Chishizhi Wan group （P<0.05） and declined in the high-dose group （P<0.01）， and the protein level of Beclin-1 was down-regulated in the medium-dose group （P<0.01）. Additionally， the trimetazidine group had higher protein level of LC3Ⅱ/Ⅰ than medium- and high-dose Wutou Chishizhi Wan groups （P<0.05， P<0.01）， higher protein level of PI3K than low-， medium-， and high-dose groups （P<0.01）， lower protein level of p-Akt than low- and medium-dose groups （P<0.01）， and higher p-GSK-3β protein level than the medium-dose group （P<0.01）. ConclusionDifferent doses of Wutou Chishizhi Wan can ameliorate MIRI， and the high dose has the best effect. Wutou Chishizhi Wan can reduce the activity of myocardial injury markers AST， CK， cTnT， and MYO， and alleviate the pathological damage of myocardial tissue. It can down-regulate the protein levels of beclin-1， LC3Ⅱ/Ⅰ， and up-regulate those of PI3K， p-Akt， and p-GSK-3β. In summary， Wutou Chishizhi Wan may inhibit excessive autophagy and regulate the PI3K/Akt/GSK-3β signaling pathway to exert protective effect on MIRI rats.