Hydroxysafflor Yellow A Inhibits Pyroptosis and Protecting HUVECs from OGD/R via NLRP3/Caspase-1/GSDMD Pathway.

OBJECTIVE: To observe the protective effect and mechanism of hydroxyl safflower yellow A (HSYA) from myocardial ischemia-reperfusion injury on human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were treated with oxygen-glucose deprivation reperfusion (OGD/R) to simulate the ischemia reperfusion model, and cell counting kit-8 was used to detect the protective effect of different concentrations (1.25-160 µ mol/L) of HSYA on HUVECs after OGD/R. HSYA 80 µ mol/L was used for follow-up experiments. The contents of inflammatory cytokines interleukin (IL)-18, IL-1 ß, monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor α (TNF-α) and IL-6 before and after administration were measured by enzyme-linked immunosorbent assay. The protein expressions of toll-like receptor, NOD-like receptor containing pyrin domain 3 (NLRP3), gasdermin D (GSDMD) and GSDMD-N-terminal domain (GSDMD-N) before and after administration were detected by Western blot. NLRP3 inflammasome inhibitor cytokine release inhibitory drug 3 sodium salt (CRID3 sodium salt, also known as MCC950) and agonist were added, and the changes of NLRP3, cysteine-aspartic acid protease 1 (Caspase-1), GSDMD and GSDMD-N protein expressions were detected by Western blot. RESULTS: HSYA inhibited OGD/R-induced inflammation and significantly decreased the contents of inflammatory cytokines IL-18, IL-1 ß, MCP-1, TNF-α and IL-6 (P<0.01 or P<0.05). At the same time, by inhibiting NLRP3/Caspase-1/GSDMD pathway, HSYA can reduce the occurrence of pyroptosis after OGD/R and reduce the expression of NLRP3, Caspase-1, GSDMD and GSDMD-N proteins (P<0.01). CONCLUSIONS: The protective effect of HSYA on HUVECs after OGD/R is related to down-regulating the expression of NLRP3 inflammasome and inhibiting pyroptosis.

Effect of electroacupuncture at Neiguan (PC6) at different time points on myocardial ischemia reperfusion arrhythmia in rats.

OBJECTIVE: To observe the effects of electroacupuncture at Neiguan (PC6) at different time points on reperfusion arrhythmia (RA) after myocardial ischemia and reperfusion in rats, and to investigate the correlation of this protective effect with nerve growth factor (NGF), tyrosine kinase A (TrkA), tyrosine hydroxylase (TH), and norepinephrine (NE). METHODS：A total of 72 Sprague-Dawley male rats were randomly divided into six groups (n = 12 rats/group): normal group (Norm), sham operation group (Sham), ischemia reperfusion group (I/R), pre-ischemic electroacupuncture group (EAI), pre-reperfusion electroacupuncture group (EAII), post-reperfusion electroacupuncture group (EAIII). The myocardial ischemia-reperfusion injury (MIRI) model was induced by occlusion of left anterior descending coronary artery for 20 min followed by reperfusion for 40 min in rats. With no intervention in the Norm group and only threading without ligation in the Sham group. Electroacupuncture pre-treatment at 20 min/d for 7 d before ligation in the EAⅠ group, 20 min of electroacupuncture before reperfusion in the EAII group and 20 min of electroacupuncture after reperfusion in the EAIII group. The electrocardiogram (ECG) of each group was recorded throughout the whole process, and the success of the MIRI model was determined based on the changs of J-point and T-wave in the ECG. The arrhythmia score was used to record premature ventricular contractions, ventricular tachycardia and ventricular fibrillation during the reperfusion period to assess the reperfusion induced arrhythmias. The expression levels of NGF, TrkA, TH protein were measured by Western blot. Moreover, the expression levels of plasma and myocardial NE levels were detected by enzyme linked immunosorbent assay. RESULTS: The differences between Norm group and Sham group were not statistically significant in all indexes. Arrhythmia score, myocardial NGF, TrkA, TH, and NE expression were significantly higher in the I/R group compared with the Sham group. Arrhythmia score, myocardial NGF, TrkA, TH, and NE expression were significantly lower in each EA group compared with the I/R group. CONCLUSION: Electroacupuncture at Neiguan (PC6) at different time points can reduce the incidence and severity of reperfusion arrhythmias in rats. This protective effect is related to electroacupuncture regulating NGF, TrkA, TH, NE expression and reducing sympathetic hyperactivation.

Kinsenoside mitigates myocardial ischemia/reperfusion-induced ferroptosis via activation of the Akt/Nrf2/HO-1 pathway.

Ischemia-induced myocardial infarction is regarded as one of the major killers of humans worldwide. Kinsenoside (KD), a primary active ingredient derived from Anoectochilus roxburghii, shows antioxidant and vascular protective properties. Myocardial ischemia/reperfusion (I/R) injury is associated with oxidative damage and could be regulated by KD. However, its targets and the exact mechanism by which it operates remains unclear. The aim of this study was to investigate the role of KD in myocardial I/R injury and to define the mechanism by which it works. We established both myocardial I/R model in vivo and hypoxia/reoxygenation (H/R) cardiomyocyte model in vitro in this study. KD can attenuate I/R-induced myocardial injury in vivo and inhibit H/R-induced injury in vitro in a dose-dependent manner. KD increased mitochondrial membrane potential, SOD activity, and GSH activity in cardiomyocytes, whereas MDA accumulation, iron accumulation, and Mito-ROS production were decreased. We intersected differentially expressed genes (DEGs) from RNA-seq results with ferroptosis-related genes, and found KD significantly downregulated COX2 expression and upregulated GPX4 expression. These findings were further confirmed by Western blot analysis. Additionally, KD increased AKT phosphorylation and Nrf2 translocation into the nucleus, as well as HO-1 expression. When Akt or Nrf2 were inhibited in the KD group, the anti-ferroptosis properties of KD were nullified. Thus, Kinsenoside may exert anti-ferroptosis effect in myocardial I/R injury by decreasing mitochondrial dysfunction and increasing anti-oxidation through the Akt/Nrf2/HO-1 signaling pathway, suggesting it could be used as a potential therapeutic agent for myocardial reperfusion injury.

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

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

Mitoprotective effect of mesenchymal stem cells-derived conditioned medium in myocardial reperfusion injury of aged rats: role of SIRT-1/PGC-1α/NRF-2 network.

BACKGROUND: The aged myocardium experiences various forms of stress that cause reduction of its tolerance to injury induced by ischemia/reperfusion (I/R). Developing effective cardioprotective modalities to prevent the amplification of I/R injury during aging is under focus of investigation. Mesenchymal stem cells (MSCs) have the ability to regenerate infarcted myocardium mostly by producing multiple secretory factors. This study aimed to explore the mechanisms of mitoprotection by MSCs-conditioned medium (CM) in myocardial I/R injury of aged rats. METHODS: Male Wistar rats (n = 72, 400-450 g, 22-24 months old) were randomized into groups with/without I/R and/or MSCs-CM treatment. To establish myocardial I/R injury, the method of LAD occlusion and re-opening was employed. MSCs-CM was administered intramyocardially (150 µl) at the onset of reperfusion in recipient group. After 24 h reperfusion, myocardial infarct size, LDH level, mitochondrial functional endpoints, expression of mitochondrial biogenesis-associated genes, and the levels of pro-inflammatory cytokines were evaluated. After 28 days reperfusion, echocardiographic assessment of cardiac function was performed. RESULTS: MSCs-CM treatment improved myocardial function and decreased infarct size and LDH level in aged I/R rats (P < .05 to P < .001). It also decreased mitochondrial ROS formation, enhanced mitochondrial membrane potential and ATP content, upregulated mitochondrial biogenesis-related genes including SIRT-1, PGC-1α, and NRF-2, and lessened TNF-α, IL-1ß, and IL-6 levels (P < .05 to P < .01). CONCLUSIONS: MSCs-CM treatment attenuated myocardial I/R injury in aged rats, in part by improving mitochondrial function and biogenesis and restraining inflammatory reaction. the upregulation of SIRT-1/PGC-1α/NRF-2 profiles is a possible target for the mitoprotective effects of MSCs-CM following I/R injury during aging.

The additive effects of nicotinamide mononucleotide and melatonin on mitochondrial biogenesis and fission/fusion, autophagy, and microRNA-499 in the aged rat heart with reperfusion injury.

The prognosis of myocardial ischemia/reperfusion (I/R) injury is poor in elderly patients. Aging increases the susceptibility of the heart to cell death from I/R injury and prevents the optimal effectiveness of cardioprotective modalities. Since the interaction of aging with cardioprotection is multifactorial, combination therapy may overcome the above-mentioned burden through correcting various components of the injury. Here, we explored the effects of nicotinamide mononucleotide (NMN)/melatonin combination therapy on mitochondrial biogenesis and fission/fusion, autophagy, and microRNA-499 in the aged rat heart with reperfusion injury. Ex vivo model of myocardial I/R injury was established by coronary occlusion and re-opening in 30 aged male Wistar rats (400-450 g, 22-24 months old). NMN (100 mg/kg/48 h, intraperitoneally) was administered over 28 days before I/R, and melatonin (50 µM) was added to the perfusion solution at early reperfusion. CK-MB release and expression of mitochondrial biogenesis genes and proteins, mitochondrial fission/fusion proteins, autophagy genes, and microRNA-499 were assessed. NMN/melatonin combination therapy concomitantly decreased CK-MB release in aged reperfused hearts (P < .001). It also upregulated SIRT1/PGC-1α/Nrf1/TFAM profiles at both gene and protein levels, Mfn2 protein, and microRNA-499 expression, and downregulated Drp1 protein and Beclin1, LC3, and p62 genes (P < .05 to P < .001). The effect of combination therapy was greater than individual ones. Co-application of NMN/melatonin within the setting of I/R injury in the aged rat heart induced noticeable cardioprotection through modulation of a coordinated network including microRNA-499 expression along with mitochondrial biogenesis associated with SIRT1/PGC-1α/Nrf1/TFAM profiles, mitochondrial fission/fusion, and autophagy, therefore, appears to prevent the burden of myocardial I/R injury in elderly patients.

Exercise for myocardial ischemia-reperfusion injury: A systematic review and meta-analysis based on preclinical studies.

The main pathological manifestation of coronary artery disease is myocardial injury caused by ischemia-reperfusion (IR) injury. Regular exercise reduces the risk of death during myocardial IR injury. The aim of this study was to describe the effects of various types of exercise on myocardial IR injury. Four electronic databases PubMed, Web of Science, Embase, and Cochrane Library were comprehensively searched from inception until February 2022, to identify studies relevant to the current review, using the method of combining subject and free words. Finally, 16 articles were included in the meta-analysis. Results showed that exercise training decreases the Myocardial infarct size compared to the control group (SMD = -2.6, 95 % CI [-3.53 to -1.67], P < 0.01); increasing the coronary blood flow (MD = 2.93, 95 % CI [2.41 to 3.44], P < 0.01), left ventricular developed pressure (SMD = 2.28, 95 % CI [0.12 to 4.43], P < 0.05), cardiac output (SMD = 1.22, 95 % CI [0.61 to 1.83], P < 0.01) compared to the control group. According to the descriptive analysis results also showed that exercise training increases the left ventricular ejection fraction, superoxide dismutase, manganese superoxide dismutase, glutathione peroxidase, copper-zinc superoxide dismutase, glutathione peroxidase, and decrease the creatine kinase, creatine kinase-MB, lactate dehydrogenase, Malondialdehyde, cardiac troponins T. Exercise can improve myocardial function after myocardial IR injury; however, further research is needed in combination with specific issues such as exercise mode, intensity, duration, and model issues.

Cardio protective effect of nicorandil in reperfusion injury among patients undergoing primary percutaneous coronary intervention.

Objectives: To evaluate the effect of nicorandil in prevention of reperfusion injury during primary percutaneous coronary intervention by thrombolysis in myocardial infarction flow grade scoring. Methods: A total of 140 patients from Rawalpindi Institute of Cardiology were enrolled in this study conducted from 7th September to 10th of October 2021. These participants were allocated into two major groups. Control group received conventional acute coronary syndrome protocol regimen only whereas experimental group was given nicorandil along with conventional acute coronary syndrome protocol. During primary percutaneous coronary intervention, thrombolysis in myocardial infarction flow grade scoring was analyzed and compared. Results: Majority of participants in nicorandil group achieved thrombolysis in myocardial infarction Grade-3 scoring which indicated reduced rate of no reflow phenomenon as compared to control group. A statistically significant difference was noted in score of both groups (p value = 0.001) signifying prophylactic use of nicorandil before primary percutaneous coronary intervention along with conventional acute coronary syndrome protocol is superior to only conventional acute coronary syndrome protocol regimen to cases in the control group. Conclusion: Use of nicorandil in ST elevated myocardial infarction patients before primary percutaneous coronary intervention prevents reperfusion injury thus decreasing the risk of post percutaneous coronary intervention complications and reducing mortality rate in cardiac patients suggesting its significant cardio protective role.

Insulin reduces pyroptosis-induced inflammation by PDHA1 dephosphorylation-mediated NLRP3 activation during myocardial ischemia-reperfusion injury.

BACKGROUND: Previous studies proved that pyrin domain-containing protein 3 (NLRP3)-induced pyroptosis plays an important role in Myocardial ischemia-reperfusion injury (MIRI). Insulin can inhibit the activation of NLRP3 inflammasome, although the exact mechanism remains unclear. The aim of this study was to determine whether insulin reduces NLRP3-induced pyroptosis by regulating pyruvate dehydrogenase E1alpha subunit (PDHA1) dephosphorylation during MIRI. METHODS: Rat hearts were subject to 30 min global ischemia followed by 60 min reperfusion, with or without 0.5 IU/L insulin. Myocardial ischemia-reperfusion injury was evaluated by measuring myocardial enzymes release, Cardiac hemodynamics, pathological changes, infarct size, and apoptosis rate. Cardiac aerobic glycolysis was evaluated by measuring ATP, lactic acid content, and pyruvate dehydrogenase complex (PDHc) activity in myocardial tissue. Recombinant adenoviral vectors for PDHA1 knockdown were constructed. Pyroptosis-related proteins were measured by Western blotting analysis, immunohistochemistry staining, and ELISA assay, respectively. RESULTS: It was found that insulin significantly reduced the area of myocardial infarction, apoptosis rate, and improved cardiac hemodynamics, pathological changes, energy metabolism. Insulin inhibits pyroptosis-induced inflammation during MIRI. Subsequently, Adeno-associated virus was used to knock down cardiac PDHA1 expression. Knockdown PDHA1 not only promoted the expression of NLRP3 but also blocked the inhibitory effect of insulin on NLRP3-mediated pyroptosis in MIRI. CONCLUSIONS: Results suggest that insulin protects against MIRI by regulating PDHA1 dephosphorylation, its mechanism is not only to improve myocardial energy metabolism but also to reduce the NLRP3-induced pyroptosis.

Effects of electroacupuncture preconditioning of "Neiguan"(PC 6) on myocardial ischemia reperfusion injury via Akt/mTOR pathway / 国际中医中药杂志

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.

Discussion on 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 / 国际中医中药杂志

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".

COVID-19 Associated Acute Viral Myocarditis and Thyroid Gland Follicular Neoplasm in a Hemodialysis Patient.

Since the first cases were reported in Wuhan, China, COVID-19 has spread swiftly worldwide and is caused by SARS-CoV-2. The development of myocardial injury is associated with significantly worse clinical course and increased mortality. However, currently, it is unclear whether cardiac injury occurred in COVID-19 patients. Histological results obtained directly from the viral infection of the myocardium (i.e., SARS-CoV-2 viral myocarditis) or indirectly from the complications of COVID-19, showed that only a portion of patients infected with the virus developed viral myocarditis. Therefore, it is possible that with more autopsy evidence of SARS-CoV-2 and more correlation with the severity of the viral infection, viral myocarditis will emerge. Although COVID-19 manifests primarily as respiratory disease, few cases of cardiac injury without respiratory involvement or febrile illness have been reported. The pathogenesis of cancer and viral infections is due to the inability of the immune system to distinguish between self and non-self. Several oncogenic (hepatitis B virus, hepatitis C virus, human papilloma virus, Epstein-Barr virus, and HIV) and oncolytic viruses (coxsackievirus, reovirus, vaccinia virus, and adenovirus) are known to cause and regress various cancer types. We report a case of atypical manifestation of COVID-19-induced acute myocarditis and thyroid gland follicular neoplasm in a hemodialysis patient with no respiratory symptoms. This case illustrates that COVID-19 can present atypically and affect non-respiratory organ systems.

Effect of metformin preconditioning on AMPK/PINK1 signaling pathway during myocardial ischemia-reperfusion injury in diabetic rats / 中华麻醉学杂志

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.

Role of bilateral superior cervical sympathetic ganglion in myocardial ischemia-reperfusion injury in mice: relationship with NLRP3 inflammasomes / 中华麻醉学杂志

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.

Effect of superior cervical ganglion block on cardiac function and NLRP3 signaling pathway in a rat model of myocardial ischemia-reperfusion / 中华麻醉学杂志

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.

Role of succinate dehydrogenase in hypoxic postconditioning-induced reduction of hypoxia-reoxygenation injury in myocardial cells of rats and the relationship with mito-K ATP / 中华麻醉学杂志

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.

Relationship between miR-27a and SIRT1 during myocardial ischemia-reperfusion in rats / 中华麻醉学杂志

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.

Role of cold-inducible RNA-binding protein in acute renal injury in a mouse model of myocardial ischemia-reperfusion: relationship with NF-κB signaling pathway / 中华麻醉学杂志

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.

Relationship Between Preprocedural Lipid Levels and Periprocedural Myocardial Injury in Patients Undergoing Elective Percutaneous Coronary Intervention.

BACKGROUND: Periprocedural myocardial injury is a predictor of cardiovascular morbidity and mortality after percutaneous coronary intervention. METHODS: The authors examined the effects of preprocedural lipid levels (low-density lipoprotein, high-density lipoprotein, and triglycerides) in 977 patients with coronary artery disease who underwent elective percutaneous coronary intervention. RESULTS: Elevated cardiac troponin I level (≥5× the upper limit of normal) was used to indicate periprocedural myocardial injury. Serum lipid samples were collected 12 hours preprocedurally. Cardiac troponin I was collected 1, 6, and 12 hours postprocedurally. Correlations between preprocedural lipid levels and postprocedural cardiac troponin I were studied. Low-density lipoprotein levels were less than 70 mg/dL in 70% of patients and greater than 100 mg/dL in only 7.4% of patients; 13% had triglyceride levels greater than or equal to 150 mg/dL, and 96% had high-density lipoprotein levels less than 40 mg/dL. Patients with elevated cardiac troponin I had significantly lower left ventricular ejection fraction than did those with cardiac troponin I levels less than 5× the upper limit of normal (P = .01). Double-and triple-vessel disease were more common in patients with elevated cardiac troponin I (P < .002). Multivariable logistic and linear regression analyses revealed no statistically significant associations between lipid levels and postprocedural cardiac troponin I elevation, possibly because such large proportions of included patients had low levels of low-density lipoprotein (70%) and a history of statin intake (86%). CONCLUSION: The authors found no association between lipid profile and periprocedural myocardial injury.