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At present,proprotein convertase subtilisin/kexin type 9(PCSK9)inhibitor has been widely used in clinical field as a fast and effective drug to reduce low density lipoprotein cholesterol(LDL-C),in addition to regulating LDL-C to affect the process of atherosclerosis.Clinical data show that PCSK9 is upregulated in ischemic heart,and downregulation of PCSK9 expression can benefit infarct size,post-infarct inflammation and remodeling,and cardiac dysfunction after ische-mia/reperfusion.In subjects with increased cardiovascular risk,PCSK9 inhibition was associated with reduced incidence rates of myocardial infarction,stroke,and coronary revascularization,as well as improved endothelial function.This article reviews the role of PCSK9 in myocardial infarction and ischemia-reperfusion after myocardial infarction.
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Objective To observe the effect of coronary reperfusion therapy on the differential ex-pression of plasma exosomal miRNAs in patients with acute myocardial infarction(AMI).Meth-ods Three elderly male AMI patients undergoing coronary reperfusion therapy in our hospital from October to November 2022 were recruited in this study.The venous blood samples were col-lected at admission and 2 and 24 h after recanalization.MiRNA-sequencing was used to screen the differentially expressed miRNAs which were commonly expressed in the plasma exosomes of the 3 patients.Bioinformatics analysis was performed on the target genes,and then the differentially expressed miR-499a-5p was verified by qPCR.Results Compared with the plasma exosomal miRNAs at admission,there were 418 up-regulated and 406 down-regulated miRNAs at 2 h after operation,and 320 up-regulated and 225 down-regulated miRNAs at 24 h after operation(P＜0.05);Compared with the miRNAs at 2 h after operation,there were 344 up-regulated and 350 down-regulated ones at 24 h after operation(P＜0.05).Kyoto Encyclopedia of Genes and Ge-nomes enrichment analysis showed that the differentially expressed miRNAs were enriched in phosphatidylinositol-3-kinase-protein kinase B,hypoxia-inducible factor 1,and vascular smooth muscle contraction pathways.Gene Ontology analysis indicated that the molecular functions of dif-ferentially expressed miRNA target genes were mainly enriched in protein binding and DNA bind-ing;cellular components were mainly enriched in cell membrane and cytoplasm;and biological processes were mainly enriched in signaling and transcription of DNA templates.The miR-499a-5p level was significantly lower at 2 h postoperatively than at admission[(0.577±0.020)vs(1.000± 0.023),P＜0.05],and at 24 h postoperatively than at 2 h postoperatively[(0.068±0.006)vs(0.577±0.020),P＜0.05].Conclusion Plasma exosomal miRNAs can be used as a biomarker for early diagnosis of elderly AMI patients and for predicting the efficacy of reperfusion therapy.
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Objective:To correlate neutrophil/lymphocyte ratio (NLR) with cardiac function in patients with acute myocardial infarction (ACI) after percutaneous coronary intervention (PCI) and investigate its clinical value in predicting major adverse cardiovascular events (MACEs) in patients.Methods:A total of 120 patients with AMI who underwent PCI at Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine from March 2020 to February 2023 were included in this prospective study. The difference in NLR measured 1 day after PCI relative to that measured at 5 days after surgery (?NLR) was correlated with cardiac function ultrasound indicators measured at 3 months after surgery, myocardial injury, and inflammatory biochemical indicators at 1 day after surgery. The MACEs occurring within 3 months after surgery were recorded. The value of ΔNLR recorded during the early stage after PCI for predicting MACEs in patients with AMI was evaluated.Results:At 3 months after surgery, 13 out of 120 patients with AMI (10.83%) had MACEs. The ?NLR in patients with AMI who had MACEs was (3.55 ± 0.47), which was significantly higher than (2.06 ± 0.34) in patients with AMI who had no MACEs ( t = 17.25, P < 0.001). An optimal critical value of ?NLR for predicting MACEs after PCI in patients with AMI was 2.75, with an area under the receiver operating characteristic curve of 0.972, a sensitivity of 90.70%, and a specificity of 91.10%. Conclusion:Increased NLR during the early stage after PCI in patients with AMI is closely related to decreased cardiac function, and worsened myocardial injury and inflammatory reactions. Changes in NLR after PCI in patients with AMI have a highly valuable value for predicting MACEs in these patients.
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Objective:To predict the mechanism of Danggui Buxue Decoction for anti-myocardial ischemia-reperfusion injury and "treating different diseases with the same method" in ischemic stroke based on network pharmacology and molecular docking.Methods:The active components and targets of Danggui Buxue Decoction were screened by retrieving the database of TCMSP and literature; the corresponding targets of myocardial ischemia-reperfusion injury and ischemic stroke were found by OMIM and GeneCards database; the intersection targets of Danggui Buxue Decoction and disease were obtained by using Venny diagram, and the common target network and protein-protein interaction network were constructed by Cytoscape 3.7.1 software and STRING database. The GO and KEGG pathways were enriched by David Database, and the Bio GPS database was used to obtain the tissue distribution information of the key targets. The molecular docking technology was used to verify the results.Results:There were 21 active components in Danggui Buxue Decoction, 181 effective targets and 93 cross targets with diseases. The key components were quercetin, Kaempferol, β-sitosterol, formononetin and isorhamnetin. The key targets were AKT1, TNF, IL6, IL-1β and VEGFA. The enrichment results showed that the main action pathways were fluid shear force and arteriosclerosis, lipid and arteriosclerosis, AGE-RAGE signal pathway in diabetic complications, and the core targets were mainly located in the medullary cells, dendritic cell, smooth muscle, prostate, thyroid and other tissues. The results of molecular docking showed that quercetin had the best binding effect to IL-1β, while isorhamnetin had the best binding effect to IL-1β.Conclusion:Danggui Buxue Decoction is against myocardial ischemia-reperfusion injury and ischemic stroke through hemodynamics, lipid metabolism, inflammatory reaction, oxidative stress, immune reaction and cell apoptosis, plays the role of "treating different diseases with the same method".
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Objective:To observe the effects of electroacupuncture preconditioning on the autophagy-related pathway protein kinase B (Akt)/mammalian target of rapamycin (mTOR) in myocardial tissue of rats with myocardial ischemia reperfusion injury (MIRI); To investigate the protective mechanism of "Neiguan"(PC 6) on myocardial injury.Methods:Totally 48 SD rats were randomly divided into blank group, sham-operation group, model group and Neiguan group ( n=12 in each group). The Neiguan group was applied to bilateral "Neiguan"(PC 6) by electroacupuncture for 30 min, once daily for consecutive 7 days before model replication. Except in the blank group, the MIRI model was established by ligation of the descending anterior branch of the left coronary artery in the rest groups after the intervention. The histomorphological changes in the myocardium of the rats were observed by HE staining, and the expression levels of Akt, phosphorylated Akt (p-Akt), mTOR and phosphorylated mTOR (p-mTOR) in the myocardium were measured by protein immunoblotting. The ratio of p-Akt/Akt and p-mTOR/mTOR was calculated. Results:In the blank group, the myocardial fibres were arranged regularly and neatly, and no inflammatory cell infiltration or haemorrhage was seen in the interstitium; in the sham-operation group, the arrangement of myocardial fibers was slightly irregular, no rupture was found, and a small amount of myocardial fiber gap was slightly enlarged; in the model group, the distribution of myocardial fibers was disordered, hypertrophic cardiomyocytes increased, some mitochondria were red and swollen or the outer membrane was ruptured, and inflammatory infiltration and hemorrhage were seen in the interstitium; the extent of myocardial lesions in the Neiguan group was less than that in the model group, with a small amount of interstitial hemorrhage and inflammatory cell infiltration. There was no statistical significance in the levels of Akt and mTOR in the myocardial tissues of the rats in each group ( P>0.05); compared with the sham-operation group, the levels of p-Akt, p-mTOR and p-Akt/Akt, p-mTOR/mTOR in the model group decreased ( P<0.01); compared with the model group, the levels of p-Akt, p-mTOR and p-Akt/Akt, p-mTOR/mTOR in the Neiguan group increased ( P<0.01). Conclusion:Electroacupuncture preconditioning may inhibit excessive autophagy by activating the Akt/mTOR pathway in cardiomyocytes of MIRI rats, thereby exerting a protective effect on the myocardium.
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Objective:To evaluate the role of cold-inducible RNA-binding protein (CIRP) in acute renal injury in a mouse model of myocardial ischemia-reperfusion (I/R) and the relationship with nuclear factor kappa B (NF-κB) signaling pathway.Methods:Twenty-four SPF-grade healthy male C57BL/6 mice, aged 6-8 weeks, with body mass index of 24-28 g, were divided into 3 groups ( n=8 each) using a random number table method: sham operation group (Sham group), myocardial I/R group (I/R group) and myocardial I/R + CIRP-derived peptide C23 group (I/R+ C23 group). The model of myocardial I/R was developed by ligation of the left anterior descending coronary artery for 30 min followed by 120-min reperfusion in anesthetized animals. CIRP-derived peptide C23 8 mg/kg was intraperitoneally injected before myocardial ischemia and reperfusion in I/R+ C23 group, while Sham group was only threaded without ligation. Blood samples were collected from the right internal carotid artery at 120 min of reperfusion for determination of the serum creatine kinase isoenzymes (CK-MB), lactic dehydrogenase (LDH), creatinine (Cr) and blood urea nitrogen (BUN) concentrations. Renal tissues were obtained for examination of the pathological changes, and the tubular injury score was assessed. The expression of NF-κB, phosphorylated NF-κB (p-NF-κB), Nod-like receptor protein 3 (NLRP3), interleukin-1beta (IL-1β) and IL-18 in renal tissues was detected by Western blot. The expression of Toll-like receptor 4 (TLR4), NLRP3, IL-1β, TNF-α and IL-6 mRNA was determined by real-time polymerase chain reaction. Results:Compared with Sham group, the levels of serum CK-MB, LDH, Cr and BUN and renal tubule injury score were significantly increased, the expression of p-NF-κB, NLRP3, IL-1β and IL-18 was up-regulated, the expression of TLR4, NLRP3, IL-1β, TNF-α and IL-6 mRNA was up-regulated ( P<0.05), and the pathological injury to renal tissues was aggravated in I/R group. Compared with I/R group, the serum CK-MB, LDH, Cr, BUN and renal tubular injury score were significantly decreased, and the expression of p-NF-κB, NLRP3, IL-1β and and IL-18 was down-regulated, the expression of TLR4, NLRP3, IL-1β, TNF-α and IL-6 mRNA was down-regulated ( P<0.05), and the pathological injury to renal tissues was alleviated in I/R+ C23 group. Conclusions:CIRP is involved in the process of acute renal injury in a mouse model of myocardial I/R, which is associated with activation of NF-κB signaling pathway and promotion of inflammatory responses.
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Objective:To evaluate the relationship between microRNA-27a (miR-27a) and silent information regulator 1 (SIRT1) during myocardial ischemia-reperfusion (I/R) in rats.Methods:Fifty clean-grade healthy male Sprague-Dawley rats, aged 2-3 months, weighing 220-280 g, were divided into 5 groups ( n=10 each) by the random number table method: sham operation group (Sham group), myocardial I/R group (I/R group), AAV9-miR-27a overexpression + myocardial I/R group (AAV+ I/R group), miR-27a antagomir + myocardial I/R group (AG+ I/R group) and AAV9-miR-27a negative control+ myocardial I/R group (NC+ I/R group). The myocardial I/R injury model was prepared by ligating the anterior descending branch of the left coronary artery for 30 min followed by 120 min reperfusion. At day 14 before ischemia, AAV9-miRNA-27a adeno-associated virus 2×10 11 v. g was injected via the tail vein in AAV+ I/R group, and AAV9-miR-27a NC 2×10 11 v. g was injected via the tail vein in NC+ I/R group. miR-27a antagomir 10 mg/kg was injected via the tail vein once a day at 3 days before ischemia in AG+ I/R group. At the end of 120 min of reperfusion, serum cardiac troponin T(cTnT), creatine kinase isoenzymes (CK-MB) and lactic dehydrogenase (LDH) concentrations and contents of glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) in myocardial tissues were determined by enzyme-linked immunosorbent assay, the percentage of myocardial infarct volume by TTC staining, the expression of miR-27a in myocardial tissues by quantitative real-time polymerase chain reaction, and the expression of SIRT1 in myocardial tissues by Western blot. Results:Compared with Sham group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly increased, the contents of GSH and SOD in myocardial tissues were decreased, MDA contents were increased, miR-27a expression was up-regulated, and SIRT1 expression was down-regulated in I/R group ( P<0.05). Compared with I/R group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly increased, the contents of GSH and SOD in myocardial tissues were decreased, MDA contents were increased, miR-27a expression was up-regulated, and SIRT1 expression was down-regulated in AAV+ I/R, and the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly decreased, the contents of GSH and SOD in myocardial tissues were increased, MDA contents were decreased, miR-27a expression was down-regulated, and SIRT1 expression was up-regulated in AG+ I/R group ( P<0.05), and no significant change was found in the parameters mentioned above in NC+ I/R group ( P>0.05). Compared with AAV+ I/R group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly decreased, the contents of GSH and SOD in myocardial tissues were increased, MDA contents were decreased, miR-27a expression was down-regulated, and SIRT1 expression was up-regulated in AG+ I/R group ( P<0.05). Conclusions:miR-27a is involved in the pathophysiological mechanism underlying myocardial I/R injury probably through inhibition of SIRT1 expression in rats.
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Objective:To evaluate the role of succinate dehydrogenase (SDH) in hypoxic postconditioning (HPC)-induced reduction of hypoxia-reoxygenation (H/R) injury in myocardial cells of rats and the relationship with mitochondrial ATP-sensitive potassium channels (mito-K ATP). Methods:Myocardial cells isolated from adult male Sprague-Dawley rats were cultured for 48 h and then divided into 7 groups ( n=24 each) using a random number table method: blank control group (Nor group), H/R group, SDHA-siRNA adenovirus+ H/R group (siRNA+ H/R group), HPC group, SDHA-siRNA adenovirus+ HPC group (siRNA+ HPC group), 5-HD+ HPC group, and SDHA-siRNA adenovirus+ 5-HD+ HPC group (siRNA+ 5-HD+ HPC group). Nor group was continuously cultured for 195 min under normoxic conditions. The H/R injury model was prepared by exposing the cells to hypoxia for 45 min in 5% CO 2 + 1% O 2 + 94% N 2, followed by reoxygenation for 150 min. The HPC method involved three cycles of 5 min reoxygenation/5 min hypoxia at the end of 45 min ischemia before 120 min reoxygenation. The mito-K ATP blocker 5-HD administration method involved adding 5-HD at a final concentration of 100 μmol/L at 30 min of hypoxia. The myocardial cells in each siRNA group were successfully transfected with SDHA-siRNA adenovirus to silence SDHA expression. The cell viability, calcium ion level, SDH activity, ATP content, degree of mitochondrial permeability transition pore (mPTP) opening, and mitochondrial membrane potential (MMP) were measured at the end of reoxygenation. Results:Compared with Nor group, the cell viability, ATP content and MMP were significantly decreased, and the degree of mPTP opening, level of calcium ion and activity of SDH were increased in H/R group ( P<0.05). Compared with H/R group, the cell viability, ATP content and MMP were significantly increased, and the degree of mPTP opening, calcium ion level and SDH activity were decreased in siRNA+ H/R group and HPC group ( P<0.05). Compared with HPC group, the cell viability, ATP content and MMP were significantly decreased, and the degree of mPTP opening, calcium ion level and SDH activity were increased in 5-HD+ HPC group ( P<0.05), and the cell viability, ATP content and MMP were significantly increased, and the degree of mPTP opening, calcium ion level and SDH activity were decreased in siRNA+ HPC group ( P<0.05). Compared with siRNA+ HPC group, the cell viability, ATP content and MMP were significantly decreased, the opening degree of mPTP and calcium ion level were increased ( P<0.05), and no significant change was found in the SDH activity in siRNA+ 5-HD+ HPC group ( P>0.05). Compared with 5-HD+ HPC group, the SDH activity was significantly decreased, and no significant change was found in the other parameters in siRNA+ 5-HD+ HPC group ( P>0.05). Conclusions:HPC alleviates H/R injury probably by reducing SDH activity and opening mito-K ATP in myocardial cells of rats.
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Objective:To evaluate the effect of superior cervical ganglion block (SCGB) on cardiac function and nucleotide like receptor protein 3 (NLRP3) signaling pathway in a rat model of myocardial ischemia-reperfusion (I/R).Methods:Sixty healthy SPF male Sprague-Dawley rats, weighing 250-300 g, aged 2-3 months, were divided into 4 groups ( n=15 each) using a random number table method: sham operation group (sham group), myocardial I/R group (IR group), myocardial I/R + normal saline group (IR+ NS group), and myocardial I/R + SCGB group (IR+ SCGB group). Myocardial I/R model was developed by ligation of the left anterior descending branch of the coronary artery for 45 min followed by restoration of blood flow in anesthetized aninals. IR+ SCGB group received SCGB (0.25% ropivacaine 0.1 ml) at 10 min before reperfusion once a day for 2 consecutive weeks, while 0.9% sodium chloride was given instead of ropivacaine in IR+ NS group. Blood samples were collected at 24 h and 14 days of reperfusion for determination of serum concentrations of norepinephrine (NE), troponin T (TnT), tumor necrosis factor-alpha (TNF-α), interleukin-18 (IL-18) and IL-1β by enzyme-linked immunosorbent assay. Echocardiography was performed before ischemia and at 14 days of reperfusion, and left ventricular short axis shortening rate (FS), ejection fraction (EF), and cardiac output (CO) were measured. The rats were sacrificed at 14 days of reperfusion and the hearts were taken for determination of the contents of norepinephrine (NE) in myocardial tissues in the infarction area (by enzyme-linked immunosorbent assay), percentage of myocardial fibrosis area (by Masson staining), M1 macrophage marker CD68 + cell count in the infarction area (by immunohistochemical method), and expression of NLRP3 and gasdermin D (GSDMD) in myocardial tissues (by Western blot). Results:Compared with Sham group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly increased, the expression of NLRP3 and GSDMD in myocardial tissues was up-regulated, CD68 + cell count was increased, and EF, CO and FS were decreased in IR group ( P<0.05). Compared with IR group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly decreased, the expression of NLRP3 and GSDMD in myocardial tissues was down-regulated, CD68 + cell count was decreased, and EF, CO and FS were increased in IR+ SCGB group ( P<0.05), and no statistically significant changes were found in the parameters mentioned above in IR+ NS group ( P>0.05). Conclusions:SCGB can improve the cardiac function in a rat model of myocardial I/R, and the mechanism may be related to the inhibition of NLRP3 signaling pathway.
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Objective:To evaluate the role of bilateral superior cervical sympathetic ganglia (SCG) in myocardial ischemia-reperfusion (I/R) injury in mice and the relationship with NOD-like receptor protein 3 (NLRP3) inflammasomes.Methods:Thirty-two healthy SPF male C57BL mice, aged 8-10 weeks, weighing 25-30 g, were divided into 4 groups ( n=8 each) by the random number table method: sham operation group (NS group), myocardial I/R group (NIR group), bilateral SCG excision group (SCGx group) and bilateral SCG excision + myocardial I/R group (SCGx+ IR group). The myocardial I/R injury model was prepared by ligating the anterior descending branch of the left coronary artery for 30 min followed by 24 h reperfusion in isoflurane-anesthetized mice. Bilateral superior cervical sympathectomy was performed at 3 days before reperfusion. Blood samples were collected from the inferior vena cava at 24 h of reperfusion for examination of pathological changes (by HE and WGA staining) and for measurement of serum creatine kinase isoenzymes (CK-MB) activity, cardiac troponin I (cTnI) concentration, norepinephrine (NE) concentration and lactic dehydrogenase (LDH) activity (by enzyme-linked immunosorbent assay), superoxide dismutase (SOD) activity (by colorimetric method), myocardial reactive oxygen species (ROS) level (by DHE method), myocardial infarct size(by TTC method), and expression of interleukin-1beta (IL-1β), IL-6, IL-10, tumor necrosis factor-alpha (TNF-α), NLRP3 mRNA (by quantitativepolymerase chain reaction ), and expression of tyrosine hydroxylase (TH), IL-1β, TNF-α, NLRP3, atrial natriuretic peptide (ANP)and brain natriuretic peptide (BNP) (by Western blot). Results:Compared with NS group, the NE concentration was significantly decreased, and TH expression was down-regulated in SCGx group, and the serum CK-MB activity, concentrations of cTnI and NE, LDH activity and myocardial ROS level were significantly increased, SOD activity was decreased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was up-regulated, and the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was up-regulated in NIR group ( P<0.05). Compared with SCGx group, the serum CK-MB activity, concentrations of cTnI and NE, LDH activity and myocardial ROS levels were significamtly increased, SOD activity was decreased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was up-regulated, and the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was up-regulated in SCGx+ NIR group ( P<0.05). Compared with NIR group, the serum CK-MB activity, cTnI concentration, LDH activity and myocardial ROS level were significantly decreased, SOD activity was increased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was down-regulated, the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was down-regulated, and myocardial infarct size was decreased in SCGx+ NIR group ( P<0.05). Conclusions:The mechanism by which bilateral SCG excision attenuates myocardial I/R injury is associated with decreased NLRP3 inflammatory inflammasome activation and inhibition of inflammatory responses in mice.
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Objective:To evaluate the effect of metformin preconditioning on adenosine monophosphate-activated protein kinase(AMPK)/PTEN-induced putative protein kinase(PINK1) signaling pathway during ischemia-reperfusion (I/R) injury in diabetic rats.Methods:Thirty-six clean-grade healthy male Sprague-Dawley rats, aged 6 weeks, weighing 120-160 g, were divided into 3 groups ( n=12 each) by the random number table method: diabetic sham operation group (DS group), diabetic myocardial I/R group (DI/R group) and diabetic myocardial I/R+ metformin preconditioning group(DI/R+ Met group). After 4 weeks of feeding a high-fat and high-glucose diet, the model of type 2 diabetes mellitus was induced by a single intraperitoneal injection of 1% streptozotocin 40 mg/kg. The myocardial I/R injury was induced by blocking the anterior descending branch of the left coronary artery for 30 min followed by 120-min reperfusion in anesthetized animals. In DI/R+ Met group, metformin 200 mg/kg was given by intragastric gavage once a day within 1 week before myocardial ischemia. Blood samples from the femoral vein were collected at 120 min of reperfusion for determination of the serum creatine kinase isoenzymes (CK-MB) and cardiac troponin I (cTnI) concentrations by enzyme-linked immunosorbent assay. Then the rats were sacrificed and myocardial tissues were obtained for examination of the pathological changes(by HE staining) and for determination of the percentage of myocardial infarct size (by the double staining of Ewan blue and TTC) and expression of myocardial autophagy-related protein Beclin-1, PTEN-induced putative kinase 1 (PINK1), phosphorylated 5′-adenosine monophosphate-activating protein kinase (p-AMPK), and ratio of microtubule-associated protein 1 light chain 3Ⅱ/Ⅰ (LC3Ⅱ/Ⅰ) (by Western blot). Results:Compared with DS group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly increased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3II/I was increased( P<0.05), and the pathological changes were aggravated in DI/R group and DI/R+ Met group. Compared with DI/R group, the percentage of myocardial infarct size and serum CK-MB and cTnI concentrations were significantly decreased, the expression of Beclin-1, p-AMPK and PINK1 in myocardial tissues was up-regulated, the ratio of LC3Ⅱ/Ⅰ was increased ( P<0.05), and the pathological changes were significantly reduced in DI/R+ Met group. Conclusions:The mechanism by which metformin preconditioning reduces myocardial I/R injury is related to activation of AMPK/PINK1 signaling pathway and up-regulation of mitochondrial autophagy in diabetic rats.
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Objective To explore the effect and mechanism of miR-92a regulating sonic hedgehog(SHH)pathway on promoting vascular regeneration after myocardial ischemia-reperfusion(I/R)injury.Methods Primary cardiomyocytes were isolated from newborn SD rats(1 to 3 days old),and then cultured to establish a cellular model of hypoxia/reoxygenation injury.The cardiomyo-cytes were divided into cardiomyocyte normoxia group and cardiomyocyte I/R group.After miR-92a mimic and inhibitor were respectively transfected into primary cardiomyocytes to overex-press or lower its expression,the cells were then grouped into control,I/R,miR-92a mimic and in-hibitor groups.CCK-8 assay was used to determine cell viability,flow cytometry was employed to detect cell apoptosis,ELISA and QT-PCR were applied to detect the expression of VEGF,b-FGF and Ang-1,and Western blotting was performed to measure the expression of SHH signaling pathway related proteins.Results The expression level of miR-92a was significantly higher in the cardiomyocytes from the ischemia/reperfusion(I/R)group than the normoxia group(3.89±0.29 vs 1.53±0.19,P＜0.01).Statistical differences were observed among the control group,miR-92a inhibitor group,I/R group,and miR-92a mimic group in the protein levels of SHH(0.57±0.13 vs 0.51±0.11 vs 0.24±0.03 vs 0.14±0.02,P＜0.01),of Smoothened(SMO,0.53±0.12 vs 0.49± 0.10 vs 0.14±0.04 vs 0.09±0.01,P＜0.01),of glioma-associated oncogene homolog 1(Gli-1,0.56±0.14 vs 0.50±0.13 vs 0.15±0.03 vs 0.08±0.01,P＜0.01),and of glioma-associated onco-gene homolog 2(Gli-2,0.58±0.11 vs 0.49±0.12 vs 0.18±0.02 vs 0.11±0.03,P＜0.01).Conclu-sion MiR-92a is abnormally highly expressed in cardiomyocytes after I/R injury,and inhibition of miR-92a can activate SHH signaling pathway to promote the expression of angiogenesis factors effectively.
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Objective To investigate the mechanism of maslinic acid on pyroptosis and inflammato-ry response in myocardial ischemia/reperfusion(IR)injury.Methods H9C2 cardiomyocytes were randomly divided into control group,control+maslinic acid group,hypoxia reoxygenation(HR)group,and HR+maslinic acid group.Cellular model of HR injury was constructed by hypoxia for 4 h and then reoxygenation for 12 h.Forty-eight male SD rats were randomly divided into Sham group,IR group,IR+maslinic acid group,IR+maslinic acid+Tri group(n=12).Rat model of myocardial IR injury was established by ligating the left anterior descending branch for 30 min followed by reperfusion for 2 h.The viability of cardiomyocytes was detected,the levels of LDH,CK-MB,IL-1β and IL-18 in the supernatant of cardiomyocytes and rat serum samples were detec-ted in each group.Drug-molecular docking was performed to predict the binding site and binding force of maslinic acid and NOD-like receptor thermal protein domain-associated protein 3(NLRP3).Western blotting was used to detect IκBα,NF-κB P65,NLRP3,apoptosis-associated speck-like protein(ASC),and gasdermid D-N terminal(GSDMD-N)in each group of cardiomyo-cytes and myocardial tissues.Results Compared with the Control group,significantly reduced cell viability,enhanced protein levels of p-IκBα,p-NF-κB P65 and higher releases of LDH,IL-1β and IL-18 were observed in the HR group(P＜0.05).Maslinic acid treatment reversed HR-induced changes in above indicators(P＜0.05).Compared with the Sham group,the protein levels of p-IκBα,p-NF-κB P65,NLRP3,ASC,GSDMD-N and the releases of serum CK-MB,LDH,IL-1βand IL-18 were significantly increased in the IR group(P＜0.05).Maslinic acid treatment also reversed above indicators induced by IR injury(P＜0.05).The protein levels of p-IκBα,p-NF-κB P65,NLRP3,ASC and GSDMD-N were significantly increased,and the releases of serum CK-MB,LDH,IL-1β and IL-18 were also elevated in the IR+maslinic acid+Tri group than the IR+maslinic acid group(1681.00±136.20 U/L vs 1251.00±213.60 U/L,1776.00±185.80 U/L vs 1330.00±172.50 U/L,4.32±0.45 vs 2.95±0.26,3.89±0.20 vs 2.47±0.29,P＜0.05).Conclusion Maslinic acid can show target intervention in NLRP3 activity,thereby inhibiting inflammatory re-sponse and cell pyroptosis,and ultimately attenuate myocardial IR injury effectively.
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Objective To explore the role of NLRP3/Caspase-3 in myocardial apoptosis induced by ischemia/reperfusion(IR)injury and its effect on myocardiocyte autophagy in rats.Methods A total of 60 SPF-grade male rats were randomly divided into sham operation,model,and nimodip-ine treatment groups,with 20 rats in each group.Rat model of myocardial IR injury was estab-lished in the rats of the two latter groups.Cardiac function was assessed,and the levels of myocar-dial enzymes and cytokines were measured.Additionally,myocardial pathological changes were de-tected using HE staining.Furthermore,flow cytometry was utilized to determine the apoptotic rate of myocardiocytes,and the autophagosomes were counted under transmission electron micro-scope.Moreover,the expression of NLRP3 and Caspase-3 was measured using RT-PCR and West-ern blotting.Results Significant differences were observed in left ventricular end diastolic pres-sure,left ventricular systolic pressure,maximal rate of rise and fall in left ventricular pressure,ap-optotic rate of myocardial cells,and levels of TNF-α,IL-6,CK,AST and LDH in the three groups(P＜0.01).Notably,both the model group and nimodipine treatment group exhibited significantly higher autophagosome than the sham operation group(10.55±1.87 and 6.32±1.43 vs 3.45±0.67 units,P＜0.01),and the nimodipine group displayed a significantly lower autophagosome count than the model group(P＜0.01).The mRNA and protein levels of NLRP3 and Caspase-3 were notably higher in the model group and nimodipine group than the sham operation group(P＜0.01),and in the model group than the nimodipine group(P＜0.01).Conclusion Myocardial IR injury in rats can increase myocardiocyte apoptosis,reduce cardiac function,induce inflammatory response,and enhance autophagosome formation,which is related to the abnormal high expression of NLRP3/Caspase-3.
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Objective To investigate the role of nitric oxide synthase(NOS)in the regulation of myocardial ischemia-reperfusion(IR)injury in ovariectomized(OVX)rats.Methods A total of 132 female SD rats were subjected,and 48 of them were randomly divided into sham operation group,IR group,OVX group and combined group,with 12 in each group.In order to explore the role of endothelous NOS(eNOS)and inducible NOS(iNOS)in ovariectomization increasing myo-cardial IR injury,another 84 mice were divided into negative sham group,negative IR group,nega-tive combined group,eNOS+IR group,eNOS combined group,iNOS small interfering RNA(si-iNOS)+IR group and si-iNOS combined group,with 12 in each group.The mice of the corre-sponding groups were injected with adeno-associated virus(AAV)overexpressing eNOS or knoc-king down iNOS via tail vein before OVX modeling.Myocardial infarct size,serum levels of lac-tate dehydrogenase(LDH)and creatine phosphokinase isoenzyme(CK-MB),LVEF,LVFS,and expression levels of eNOS and iNOS in the myocardial tissues were measured.Results The com-bined group had significantly increased level of iNOS in myocardium,larger myocardial infarct size and elevated serum LDH and CK-MB levels,but decreased myocardial expression of eNOS and LVEF and LVFS values than the IR group(P＜0.05).When compared with the negative combined group,the myocardial infarct size and serum LDH and CK-MB levels were decreased[(23.51±3.22)％and(26.21±2.93)％vs(58.78±5.42)％,(176.31±15.48 and 169.52±17.12 vs 328.85±37.12 U/L,35.41±6.41 and 34.77±5.94 vs 88.73±9.14 U/L,P＜0.05],and the LVEF and LVFS values were increased[(41.31±3.12)％and(42.09±3.41)％vs(30.77± 2.15)％,(21.47±1.57)％and(21.32±1.42)％vs(15.92±1.33)％,P＜0.05]in the eNOS com-bined group and si-iNOS combined group.Conclusion The decrease of eNOS expression and in-crease of iNOS expression are related to the aggravation of myocardial IR injury in OVX rats.
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Objective:To evaluate the effects of exosomes derived from cardiac fibroblasts treated with hypothermic hypoxia-reoxygenation on ventricular electrical conduction during hypothermic cardiac ischemia-reperfusion (I/R) in rats.Methods:SPF neonatal Sprague-Dawley rats of either sex, aged 1-2 days, were used, and primary cardiac fibroblasts were extracted by differential adhesion method. The cells were passaged for 2-4 generations. When the cell density reached 60%-70%, the cells were transferred and exposed to 95% N 2 + 5% CO 2 for 1 h at 4 ℃, and then exposed to 95% air + 5% CO 2 for 24-48 h at 37 ℃, and then exosomes were extracted. Twenty-four SPF healthy adult male Sprague-Dawley rats, aged 2-3 months, weighing 280-360 g, were divided into 3 groups ( n=8 each) according to the random number table method: control group (group C), hypothermic cardiac IR group (I/R group) and exosome + hypothermic cardiac IR group (Exo-IR group). At 48 h before equilibrium perfusion, 1.5 ml (200 μg) of exosomes secreted by cardiac fibroblasts treated with hypothermic hypoxia-reoxygenation was injected into the tail vein in Exo-IR group, and PBS 1.5 ml was injected into the tail vein in C group and IR group each. Group C received 110 min equilibration perfusion. After 20 min of equilibration, the perfusion was suspended for 60 min (global ischemia) followed by 30 min of reperfusion in IR and Exo-IR groups. Microelectrode arrays were applied at 20 min of equilibrium perfusion and 15 and 30 min of reperfusion to obtain myocardial conduction velocity (CV), absolute conduction inhomogeneity (P 5-95) and inhomogeneity index (P 5-95/P 50) on the left ventricular surface of isolated rat hearts. Results:Compared with group C, the CV was significantly decreased at 15 and 30 min of reperfusion, and P 5-95 and P 5-95/P 50 were increased in IR and Exo-IR groups ( P<0.05). Compared with IR group, CV was significantly increased at 15 and 30 min of reperfusion, and P 5-95 and P 5-95/P 50 were decreased in Exo-IR group ( P<0.05). Conclusions:Exosomes derived from cardiac fibroblasts treated with hypothermic hypoxia-reoxygenation can improve ventricular electrical conduction during hypothermic cardiac I/R in rats.
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Resumo Fundamento A estratificação do risco de morte dos pacientes no contexto da angioplastia primária (ATC) é fundamental. Objetivo Identificar os fatores relacionados ao desfecho morte em pacientes submetidos a ATC. Métodos Estudo de caso-controle, utilizando como fonte de dados um registro brasileiro. A associação entre cada variável e o desfecho óbito foi avaliada via modelo de regressão logística binária. Consideramos significativo p<0,05. Resultados Foram analisados 26.990 registros, sendo 18.834 (69,8%) do sexo masculino, com idade mediana de 61 (17) anos. Na análise multivariada, as principais variáveis relacionadas ao desfecho óbito com seus respectivos odds ratio e intervalos de confiança (IC) com nível de significância de 95% foram a idade avançada 70 - 79 anos (2,46; 1,64 - 3,79) e ≥ 80 anos (3,68; 2,38 - 5,81), p<0,001, classificação de Killip II (2,71; 1,92 - 3,83), Killip III (8,14; 5,67 - 11,64), Killip IV (19,83; 14,85 - 26,69), p<0,001, disfunção global acentuada do ventrículo esquerdo (VE) (3,63; 2,39 - 5,68), p<0,001 e ocorrência de infarto após a intervenção (5,01; 2,57- 9,46), p<0,001. O principal fator protetor foi o fluxo TIMI III pós-intervenção (0,18; 0,13 - 0,24), p<0,001, seguido do TIMI II (0,59; 0,41 - 0,86), p=0,005, sexo masculino (0,79; 0,64 - 0,98), p= 0,032, dislipidemia (0,69; 0,59 - 0,85), p<0,001 e número de lesões tratadas (0,86; 0,9 - 0,94), p<0,001. Conclusão Os preditores de mortalidade nos pacientes submetidos a ATC foram: classificação de Killip, reinfarto, idade, disfunção global acentuada do VE, sexo feminino e fluxo TIMI 0/I pós-intervenção.
Abstract Background Identification of high-risk patients undergoing primary angioplasty (PCI) is essential. Objective Identify factors related to the causes of death in PCI patients. Methods This work consisted of a multicenter case-control study using a Brazilian registry of cardiovascular interventions as the data source. The association between each variable and death was assessed using a binary logistic regression model, p <0.05 was considered significant. Results A total of 26,990 records were analyzed, of which 18,834 (69.8%) were male patients, with a median age of 61 (±17) years. In the multivariate analysis, the main variables related to the causes of death with their respective odds ratios and 95%confidence intervals (CI) were advanced age, 70-79 years (2.46; 1.64-3.79) and ≥ 80 years (3.69; 2.38-5.81), p<0.001; the classification of Killip II (2.71; 1.92-3.83), Killip III (8.14; 5.67-11.64), and Killip IV (19.83; 14.85-26.69), p<0.001; accentuated global dysfunction (3.63; 2,39-5.68), p<0.001; and the occurrence of infarction after intervention (5.01; 2.57-9.46), p<0.001. The main protective factor was the post-intervention thrombolysis in myocardial infarction (TIMI) III flow (0.18; 0.13-0.24), p<0.001, followed by TIMI II (0.59; 0.41 -0.86), p=0.005, and male (0.79; 0.64-0.98), p = 0.032; dyslipidemia (0.69; 0.59-0.85), p<0.001; and number of lesions treated (0.86; 0.9-0.94), p<0.001. Conclusion The predictors of mortality in patients undergoing PCI were Killip's classification, reinfarction, advanced age, severe left ventricular dysfunction, female gender, and post-intervention TIMI 0 / I flow.