1.Viral myocarditis serum exosome-derived miR-320 promotes the apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway and targeting phosphatidylinositol 3-kinase regulatory subunit 1 (Pik3r1).
Xin ZHANG ; Xueqin LI ; Liangyu ZHU ; Guoquan YIN ; Yuan ZHANG ; Kun LYU
Chinese Journal of Cellular and Molecular Immunology 2023;39(6):516-525
Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.
Mice
;
Animals
;
Myocytes, Cardiac
;
Phosphatidylinositol 3-Kinase/metabolism*
;
Proto-Oncogene Proteins c-akt/metabolism*
;
Myocarditis/pathology*
;
Exosomes/metabolism*
;
bcl-2-Associated X Protein/metabolism*
;
MicroRNAs/metabolism*
;
TOR Serine-Threonine Kinases/metabolism*
;
Apoptosis/genetics*
2.Pathological study on the relationship between nucleic acid oxidative stress and heart failure with preserved ejection fraction in patients aged over 85 years.
Wan Rong ZHU ; Ke CHAI ; Fang FANG ; Shu Rong HE ; Ying Ying LI ; Ming Hui DU ; Jun Jie LI ; Jie Fu YANG ; Jian Ping CAI ; Hua WANG
Chinese Journal of Cardiology 2023;51(10):1063-1068
Objective: To investigate the level of nucleic acid oxidation in myocardial tissue of patients aged over 85 with heart failure with preserved ejection fraction (HFpEF) and the correlation with myocardial amyloid deposition. Methods: This was a retrospective case-control study. Data of patients≥85 years old who underwent systematic pathological autopsy in Beijing Hospital from 2003 to 2017 were retrospectively collected. Twenty-six patients were included in the HFpEF group and 13 age-and sex-matched patients who had not been diagnosed with heart failure and died of non-cardiovascular diseases served as the control group. The left ventricular myocardium slices of both groups were semi-quantitatively analyzed using immunohistochemical staining of 8-oxidized guanine riboside (8-oxo-G) and 8-oxidized guanine deoxyriboside (8-oxo-dG) to evaluate the oxidation of RNA and DNA in cardiomyocytes. Using the median of the mean absorbance value of 8-oxo-G immunohistochemical staining as the cut-off value, patients were divided into high-absorbance group and low-absorbance group. Congo red staining was used to compare myocardial amyloid deposition between the two groups. Results: The mean age of patients in HFpEF group was (91.8±3.7) years, 24 (92.3%) were males. The mean age of patients in control group was (91.7±3.7) years old, 11 (84.6%) were males. The median mean optical absorbance value of 8-oxo-G immunohistochemical staining of myocardium was significantly higher in HFpEF patients than in control group (0.313 8 (0.302 2, 0.340 6) vs. 0.289 2 (0.276 7, 0.299 4), Z=-3.245, P=0.001). The median mean absorbance value of 8-oxo-dG immunohistochemical staining of myocardial tissue was similar between the two groups (0.300 0 (0.290 0, 0.322 5) vs. 0.300 0 (0.290 0, 0.320 0), Z=-0.454, P=0.661). Proportion of patients with moderate and severe cardiac amyloid deposition was significantly higher in the high-absorbance group than in the low-absorbance group ((85.0%, 17/20) vs. (31.6%, 6/19), P=0.001). Conclusion: The RNA oxidation degree of myocardium in HFpEF patients is higher than that in elderly people without heart failure. Degree of myocardial amyloid deposits is higher in patients with high levels of RNA oxidation.
Aged
;
Male
;
Humans
;
Aged, 80 and over
;
Female
;
Heart Failure/pathology*
;
Retrospective Studies
;
Stroke Volume
;
Case-Control Studies
;
Nucleic Acids
;
8-Hydroxy-2'-Deoxyguanosine
;
Myocytes, Cardiac/pathology*
;
RNA
;
Oxidative Stress
;
Guanine
;
Ventricular Function, Left
3.Pathological study on the relationship between nucleic acid oxidative stress and heart failure with preserved ejection fraction in patients aged over 85 years.
Wan Rong ZHU ; Ke CHAI ; Fang FANG ; Shu Rong HE ; Ying Ying LI ; Ming Hui DU ; Jun Jie LI ; Jie Fu YANG ; Jian Ping CAI ; Hua WANG
Chinese Journal of Cardiology 2023;51(10):1063-1068
Objective: To investigate the level of nucleic acid oxidation in myocardial tissue of patients aged over 85 with heart failure with preserved ejection fraction (HFpEF) and the correlation with myocardial amyloid deposition. Methods: This was a retrospective case-control study. Data of patients≥85 years old who underwent systematic pathological autopsy in Beijing Hospital from 2003 to 2017 were retrospectively collected. Twenty-six patients were included in the HFpEF group and 13 age-and sex-matched patients who had not been diagnosed with heart failure and died of non-cardiovascular diseases served as the control group. The left ventricular myocardium slices of both groups were semi-quantitatively analyzed using immunohistochemical staining of 8-oxidized guanine riboside (8-oxo-G) and 8-oxidized guanine deoxyriboside (8-oxo-dG) to evaluate the oxidation of RNA and DNA in cardiomyocytes. Using the median of the mean absorbance value of 8-oxo-G immunohistochemical staining as the cut-off value, patients were divided into high-absorbance group and low-absorbance group. Congo red staining was used to compare myocardial amyloid deposition between the two groups. Results: The mean age of patients in HFpEF group was (91.8±3.7) years, 24 (92.3%) were males. The mean age of patients in control group was (91.7±3.7) years old, 11 (84.6%) were males. The median mean optical absorbance value of 8-oxo-G immunohistochemical staining of myocardium was significantly higher in HFpEF patients than in control group (0.313 8 (0.302 2, 0.340 6) vs. 0.289 2 (0.276 7, 0.299 4), Z=-3.245, P=0.001). The median mean absorbance value of 8-oxo-dG immunohistochemical staining of myocardial tissue was similar between the two groups (0.300 0 (0.290 0, 0.322 5) vs. 0.300 0 (0.290 0, 0.320 0), Z=-0.454, P=0.661). Proportion of patients with moderate and severe cardiac amyloid deposition was significantly higher in the high-absorbance group than in the low-absorbance group ((85.0%, 17/20) vs. (31.6%, 6/19), P=0.001). Conclusion: The RNA oxidation degree of myocardium in HFpEF patients is higher than that in elderly people without heart failure. Degree of myocardial amyloid deposits is higher in patients with high levels of RNA oxidation.
Aged
;
Male
;
Humans
;
Aged, 80 and over
;
Female
;
Heart Failure/pathology*
;
Retrospective Studies
;
Stroke Volume
;
Case-Control Studies
;
Nucleic Acids
;
8-Hydroxy-2'-Deoxyguanosine
;
Myocytes, Cardiac/pathology*
;
RNA
;
Oxidative Stress
;
Guanine
;
Ventricular Function, Left
4.Shenmai Injection Attenuates Myocardial Ischemia/Reperfusion Injury by Targeting Nrf2/GPX4 Signalling-Mediated Ferroptosis.
Sheng-Lan MEI ; Zhong-Yuan XIA ; Zhen QIU ; Yi-Fan JIA ; Jin-Jian ZHOU ; Bin ZHOU
Chinese journal of integrative medicine 2022;28(11):983-991
OBJECTIVE:
To examine the effect of Shenmai Injection (SMJ) on ferroptosis during myocardial ischemia reperfusion (I/R) injury in rats and the underlying mechanism.
METHODS:
A total of 120 SPF-grade adult male SD rats, weighing 220-250 g were randomly divided into different groups according to a random number table. Myocardial I/R model was established by occluding the left anterior descending artery for 30 min followed by 120 min of reperfusion. SMJ was injected intraperitoneally at the onset of 120 min of reperfusion, and erastin (an agonist of ferroptosis), ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) and ML385 (an inhibitor of nuclear factor erythroid-2 related factor 2 (Nrf2)) were administered intraperitoneally separately 30 min before myocardial ischemia as different pretreatments. Cardiac function before ischemia, after ischemia and after reperfusion was analysed. Pathological changes in the myocardium and the ultrastructure of cardiomyocytes were observed, and the myocardial infarction area was measured. Additionally, the concentration of Fe2+ in heart tissues and the levels of creatine kinase-MB (CK-MB), troponin I (cTnl), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum were measured using assay kits, and the expressions of Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) were examined by Western blot.
RESULTS:
Compared with the sham group, I/R significantly injured heart tissues, as evidenced by the disordered, ruptured and oedematous myocardial fibres; the increases in infarct size, serum CK-MB, cTnI and MDA levels, and myocardial Fe2+ concentrations; and the decreases in SOD activity (P<0.05). These results were accompanied by ultrastructural alterations to the mitochondria, increased expression of ACSL4 and inhibited the activation of Nrf2/GPX4 signalling (P<0.05). Compared with I/R group, pretreatment with 9 mL/kg SMJ and 2 mg/kg Fer-1 significantly reduced myocardial I/R injury, Fe2+ concentrations and ACSL4 expression and attenuated mitochondrial impairment, while 14 mg/kg erastin exacerbated myocardial I/R injury (P<0.05). In addition, cardioprotection provided by 9 mL/kg SMJ was completely reversed by ML385, as evidenced by the increased myocardial infarct size, CK-MB, cTnI, MDA and Fe2+ concentrations, and the decreased SOD activity (P<0.05).
CONCLUSIONS
Ferroptosis is involved in myocardial I/R injury. Pretreatment with SMJ alleviated myocardial I/R injury by activating Nrf2/GPX4 signalling-mediated ferroptosis, thereby providing a strategy for the prevention and treatment of ischemic heart diseases.
Animals
;
Male
;
Rats
;
Coenzyme A
;
Creatine Kinase
;
Ferroptosis
;
Ligases
;
Malondialdehyde
;
Myocardial Infarction/drug therapy*
;
Myocardial Ischemia/drug therapy*
;
Myocardial Reperfusion Injury/pathology*
;
Myocytes, Cardiac/metabolism*
;
NF-E2-Related Factor 2/metabolism*
;
Phospholipid Hydroperoxide Glutathione Peroxidase
;
Rats, Sprague-Dawley
;
Superoxide Dismutase/metabolism*
;
Troponin I
5.Sacubitril/valsartan attenuates left ventricular remodeling and improve cardiac function by upregulating apelin/APJ pathway in rats with heart failure.
Hong Zhi LIU ; Chuan Yu GAO ; Fang YUAN ; Yu XU ; Huan TIAN ; Su Qin WANG ; Peng Fei ZHANG ; Ya Nan SHI ; Jing Jing WEI
Chinese Journal of Cardiology 2022;50(7):690-697
Objective: To investigate the effect and mechanism of sacubitril/valsartan on left ventricular remodeling and cardiac function in rats with heart failure. Methods: A total of 46 SPF-grade male Wistar rats weighed 300-350 g were acclimatized to the laboratory for 7 days. Rats were then divided into 4 groups: the heart failure group (n=12, intraperitoneal injection of adriamycin hydrochloride 2.5 mg/kg once a week for 6 consecutive weeks, establishing a model of heart failure); heart failure+sacubitril/valsartan group (treatment group, n=12, intragastric administration with sacubitril/valsartan 1 week before the first injection of adriamycin, at a dose of 60 mg·kg-1·d-1 for 7 weeks); heart failure+sacubitril/valsartan+APJ antagonist F13A group (F13A group, n=12, adriamycin and sacubitril/valsartan, intraperitoneal injection of 100 μg·kg-1·d-1 APJ antagonist F13A for 7 weeks) and control group (n=10, intraperitoneal injection of equal volume of normal saline). One week after the last injection of adriamycin or saline, transthoracic echocardiography was performed to detect the cardiac structure and function, and then the rats were executed, blood and left ventricular specimens were obtained for further analysis. Hematoxylin-eosin staining and Masson trichrome staining were performed to analyze the left ventricular pathological change and myocardial fibrosis. TUNEL staining was performed to detect cardiomyocyte apoptosis. mRNA expression of left ventricular myocardial apelin and APJ was detected by RT-qRCR. ELISA was performed to detect plasma apelin-12 concentration. The protein expression of left ventricular myocardial apelin and APJ was detected by Western blot. Results: Seven rats survived in the heart failure group, 10 in the treatment group, and 8 in the F13A group. Echocardiography showed that the left ventricular end-diastolic diameter (LVEDD) and the left ventricular end-systolic diameter (LVESD) were higher (both P<0.05), while the left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were lower in the heart failure group than in the control group (both P<0.05). Compared with the heart failure group, rats in the treatment group were featured with lower LVEDD and LVESD (both P<0.05), higher LVEF and LVFS (both P<0.05), these beneficial effects were reversed in rats assigned to F13A group (all P<0.05 vs. treatment group). The results of HE staining showed that the cardiomyocytes of rats in the control group were arranged neatly and densely structured, the cardiomyocytes in the heart failure group were arranged in disorder, distorted and the gap between cells was increased, the cardiomyocytes in the treatment group were slightly neat and dense, and cardiomyocytes in the F13A group were featured similarly as the heart failure group. Masson staining showed that there were small amount of collagen fibers in the left ventricular myocardial interstitium of the control group, while left ventricular myocardial fibrosis was significantly increased, and collagen volume fraction (CVF) was significantly higher in the heart failure group than that of the control group (P<0.05). Compared with the heart failure group, the left ventricular myocardial fibrosis and the CVF were reduced in the treatment group (both P<0.05), these effects were reversed in the F13A group (all P<0.05 vs. treatment group). TUNEL staining showed that the apoptosis index (AI) of cardiomyocytes in rats was higher in the heart failure group compared with the control group (P<0.05), which was reduced in the treatment group (P<0.05 vs. heart failure group), this effect again was reversed in the F13A group (P<0.05 vs. treatment group). The results of RT-qPCR and Western blot showed that the mRNA and protein levels of apelin and APJ in left ventricular myocardial tissue of rats were downregulated in heart failure group (all P<0.05) compared with the control group. Compared with the heart failure group, the mRNA and protein levels of apelin and APJ were upregulated in the treatment group (all P<0.05), these effects were reversed in the F13A group (all P<0.05 vs. treatment group). ELISA test showed that the plasma apelin concentration of rats was lower in the heart failure group compared with the control group (P<0.05); compared with the heart failure group, the plasma apelin concentration of rats was higher in the treatment group (P<0.05), this effect was reversed in the F13A group (P<0.05 vs. treatment group). Conclusion: Sacubitril/valsartan can partially reverse left ventricular remodeling and improve cardiac function in rats with heart failure through modulating Apelin/APJ pathways.
Aminobutyrates/pharmacology*
;
Animals
;
Apelin/metabolism*
;
Biphenyl Compounds
;
Collagen/metabolism*
;
Doxorubicin/pharmacology*
;
Fibrosis
;
Heart Failure/pathology*
;
Male
;
Myocytes, Cardiac/pathology*
;
RNA, Messenger/metabolism*
;
Rats
;
Rats, Wistar
;
Valsartan/pharmacology*
;
Ventricular Function, Left/drug effects*
;
Ventricular Remodeling
6.Oral administration of TRPV4 inhibitor improves atrial calcium handling abnormalities in sterile pericarditis rats.
Jie LIAO ; Shuai-Tao YANG ; Kai LU ; Yang LU ; Yu-Wei WU ; Yi-Mei DU
Acta Physiologica Sinica 2022;74(2):188-200
Atrial Ca2+ handling abnormalities, mainly involving the dysfunction of ryanodine receptor (RyR) and sarcoplasmic reticulum Ca2+-ATPase (SERCA), play a role in the pathogenesis of atrial fibrillation (AF). Previously, we found that the expression and function of transient receptor potential vanilloid subtype 4 (TRPV4) are upregulated in a sterile pericarditis (SP) rat model of AF, and oral administration of TRPV4 inhibitor GSK2193874 alleviates AF in this animal model. The aim of this study was to investigate whether oral administration of GSK2193874 could alleviate atrial Ca2+ handling abnormalities in SP rats. A SP rat model of AF was established by daubing sterile talcum powder on both atria of Sprague-Dawley (SD) rats after a pericardiotomy, to simulate the pathogenesis of postoperative atrial fibrillation (POAF). On the 3rd postoperative day, Ca2+ signals of atria were collected in isolated perfused hearts by optical mapping. Ca2+ transient duration (CaD), alternan, and the recovery properties of Ca2+ transient (CaT) were quantified and analyzed. GSK2193874 treatment reversed the abnormal prolongation of time to peak (determined mainly by RyR activity) and CaD (determined mainly by SERCA activity), as well as the regional heterogeneity of CaD in SP rats. Furthermore, GSK2193874 treatment relieved alternan in SP rats, and reduced its incidence of discordant alternan (DIS-ALT). More importantly, GSK2193874 treatment prevented the reduction of the S2/S1 CaT ratio (determined mainly by RyR refractoriness) in SP rats, and decreased its regional heterogeneity. Taken together, oral administration of TRPV4 inhibitor alleviates Ca2+ handling abnormalities in SP rats primarily by blocking the TRPV4-Ca2+-RyR pathway, and thus exerts therapeutic effect on POAF.
Administration, Oral
;
Animals
;
Atrial Fibrillation/etiology*
;
Calcium/metabolism*
;
Myocytes, Cardiac/metabolism*
;
Pericarditis/pathology*
;
Rats
;
Rats, Sprague-Dawley
;
Ryanodine Receptor Calcium Release Channel/pharmacology*
;
Sarcoplasmic Reticulum/pathology*
;
TRPV Cation Channels
7.Honokiol reduces doxorubicin-induced cardiotoxicity in vitro by inhibiting pyroptosis via activating AMPK/Nrf2 signaling.
Feng Mei XIONG ; Rui Ping LIU ; Yang LI ; Na SUN
Journal of Southern Medical University 2022;42(8):1205-1211
OBJECTIVE:
To investigate the effect of honokiol (HKL) for reducing doxorubicin (DOX)-induced cardiotoxicity in H9c2 cells and the underlying mechanisms.
METHODS:
H9c2 cells were divided into control group, DOX group, HKL + DOX group, and HKL+compound C+DOX group. After 24 h of corresponding treatment, the cells were examined for morphological changes and cell viability using CCK-8 assay. The mRNA expressions of the inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were detected by RT-PCR, and the protein levels of cleaved caspase-3, cytochrome c, NOD-like receptor pyrin domain containing 3 (NLRP3), caspase-1, apoptosis-associated speck-like protein containing a CARD (ASC), p-AMPK and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) were detected with Western blotting; the expressions of NLRP3 and p-AMPK also detected with immunofluorescence staining.
RESULTS:
DOX treatment caused swelling and significantly lowered the viability of H9c2 cells (P < 0.05), resulting also in increased mRNA expressions of TNF-α, IL-6 and IL-1β (P < 0.05) and protein expressions of cleaved caspase-3, cytochrome c, NLRP3, caspase-1 and ASC (P < 0.05) but reduced protein levels of p-AMPK and Nrf2 (P < 0.05); fluorescence staining showed significantly increased NLRP3 expression and decreased expression of p-AMPK in DOX-treated cells (P < 0.05). All these changes in COX-treated cells were significantly alleviated by HKL treatment (P < 0.05). The application of compound C obviously mitigated the protective effects of HKL against DOX-induced cardiotoxicity in H9c2 cells.
CONCLUSIONS
HKL can alleviate DOX-induced cardiotoxicity by inhibiting pyroptosis in H9c2 cells, and this effect is mediated by activation of AMPK to regulate Nrf2 signaling.
AMP-Activated Protein Kinases/metabolism*
;
Allyl Compounds
;
Biphenyl Compounds
;
Cardiotoxicity/pathology*
;
Caspase 3/metabolism*
;
Cytochromes c
;
Doxorubicin/adverse effects*
;
Humans
;
Interleukin-6/metabolism*
;
Myocytes, Cardiac
;
NF-E2-Related Factor 2/metabolism*
;
NLR Family, Pyrin Domain-Containing 3 Protein/metabolism*
;
Phenols
;
Pyroptosis
;
RNA, Messenger/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
8.Overexpression of miR-130a-3p attenuates cardiomyocyte hypertrophy.
Xiaojiao WANG ; Jing QU ; Dongxu LI ; Junli LI ; Wenchao WU ; Xiaojing LIU
Journal of Biomedical Engineering 2020;37(2):340-348
This study aimed to explore the role of miR-130a-3p in cardiomyocyte hypertrophy and its underlying mechanisms. Pressure-overload induced myocardial hypertrophy mice model was constructed by thoracic aortic constriction (TAC). , norepinephrine (NE) was used to stimulate neonatal rat cardiomyocytes (NRCMs) and H9c2 rat cardiomyocytes to induce hypertrophic phenotypes. The expression of miR-130a-3p was detected in mice hypertrophic myocardium, hypertrophic NRCMs and H9c2 cells. The mimics and inhibitors of miR-130a-3p were transfected into H9c2 cells to observe the role of miR-130a-3p on the hypertrophic phenotype change of cardiomyocytes separately. Furthermore, whether miR-130a-3p regulated hypertrophic related signaling pathways was explored. The results showed that the expression of miR-130a-3p was significantly decreased in hypertrophic myocardium, hypertrophic NRCMs and H9c2 cells. After transfection of miR-130a-3p mimics, the expression of hypertrophic marker genes, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC), and the cell surface area were notably down-regulated compared with the control group (mimics N.C. + NE group). But after transfection of miR-130a-3p inhibitor, the expression of ANP, BNP and β-MHC in H9c2 cells increased significantly, and the cell area increased further. By Western blot, it was found that the protein phosphorylation level of Akt and mTOR were down-regulated after over-expression of miR-130a-3p. These results suggest that miR-130a-3p mimics may alleviate the degree of cardiomyocyte hypertrophy, meanwhile its inhibitor can further aggravate cardiomyocyte hypertrophy. Over-expression of miR-130a-3p may attenuate cardiomyocytes hypertrophy by affecting the Akt pathway.
Animals
;
Atrial Natriuretic Factor
;
Cardiomegaly
;
Mice
;
MicroRNAs
;
genetics
;
Myocardium
;
pathology
;
Myocytes, Cardiac
;
pathology
;
Myosin Heavy Chains
;
Natriuretic Peptide, Brain
;
Nonmuscle Myosin Type IIB
;
Proto-Oncogene Proteins c-akt
;
Rats
9.Effects of Notch signal on the expressions of HIF-α and autophagy- related genes Beclin1, LC3I, LC3II in oxygen-glucose deprivation induced myocardial cell injury.
Ling Yu KONG ; Zan XI ; Wen Ting MA ; Fei Yun YANG ; Li Dan NIU ; Jin He SHI
Chinese Journal of Applied Physiology 2019;35(2):165-168
OBJECTIVE:
To investigate the effects of Notch signal on hypoxic induction factor (HIF-1α) and autophagy-associated genes Beclin1, LC3I, LC3II in oxygen-glucose deprivation (OGD) induced myocardial cell injury.
METHODS:
The OGD model was established using hypoxic culture box and hypoglycemic DMEM medium. The cells were divided into normal control group, OGD group, OGD + NC siRNA group, OGD + Notch1 siRNA group and OGD + HIF-1α siRNA group. Western blot was used to detect the interference effects of HIF-1α siRNA and Notch1 siRNA. The effects of Notch1 siRNA and HIF-1α siRNA on the activity of myocardial cells in OGD model were detected by the CCK-8 assay. The effects of Notch1 siRNA and HIF-1α siRNA on autophage-associated genes Beclin1, LC3I and LC3II expression were detected by Western blot.
RESULTS:
The results of Western blot showed that HIF-1α siRNA could effectively knock down the expression of HIF-1α in myocardial cells in OGD model, and Notch1 siRNA could effectively knock down the expression of Notch1 and HIF-1α in myocardial cells in OGD model. The result of CCK-8 assay showed that Notch1 siRNA and HIF-1α siRNA reduced the activity of myocardial cells in OGD model, and there was no statistical difference between the two groups. Western blot results showed that Notch1 siRNA and HIF-1α siRNA could reduce the expressions of the autophagy-associated genes Beclin1, LC3I and LC3II, and reduce the ratio of LC3II to LC3I at mRNA level.
CONCLUSION
Notch1 plays a role in myocardial protection by regulating the expression of HIF-1α to regulate the autophagy in OGD model cells.
Autophagy
;
Beclin-1
;
metabolism
;
Cell Hypoxia
;
Cells, Cultured
;
Glucose
;
Humans
;
Hypoxia-Inducible Factor 1, alpha Subunit
;
metabolism
;
Microtubule-Associated Proteins
;
metabolism
;
Myocytes, Cardiac
;
cytology
;
pathology
;
Oxygen
;
Receptors, Notch
;
metabolism
;
Signal Transduction
10.Effects of high glucose induced primary cardiomyocytes injury on necroptosis and the related mechanism.
Ting Ting FANG ; Rui Ping CAO ; Hong Wei YE ; Shan Feng MA ; Qin GAO
Chinese Journal of Applied Physiology 2019;35(2):160-164
OBJECTIVE:
To observe whether necroptosis was happened in high glucose (HG) - induced primary cardiomyocytes injury and to investigate the likely mechanism.
METHODS:
The primary cultured cardiomyocytes were divided into 4 groups (n=9): control group (the cardiomyocytes were incubated with 5.5 mmol/L glucose for 48 h), HG group (the cardiomyocytes were incubated with 30 mmol/L glucose for 48 h), HG + necrostatin-1 (Nec-1) group (the cardiomyocytes was co-incubated with necroptosis inhibitor Nec-1 at 100 μmol/L and HG for 48 h) and hypertonic pressure group (HPG, the cardiomyocytes was co-incubated with 5.5 mmol/L glucose and 24.5 mmol/L mannitol for 48 h). Cell viability was measured by MTT method, reactive oxygen species (ROS) generation was measured by DHE staining. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were tested by ELISA method. The mRNA and protein expressions of necroptosis related genes receptor interacting serine/threonine protein kinase 1 (RIP1), RIP3, mixed lineage kinase domain-like protein (MLKL) were tested by quantitative real-time PCR and Western blot.
RESULTS:
The results showed HG intervention decreased cardiomyocytes viability, increased ROS generation, up-regulated the levels of TNF-α, IL-6 and IL-1β, increased RIP1, RIP3, MLKL expressions at mRNA and protein levels. Nec-1 treatment attenuated HG-induced increased cardiomyocytes viability, reduced ROS generation, down-regulated the levels of TNF-α, IL-6 and IL-1β, decreased RIP1, RIP3, MLKL expressions at mRNA and protein levels.
CONCLUSION
Necroptosis was happened in high glucose-induced primary cardiomyocytes injury. Inhibition of necroptosis can reduce high glucose-induced cardiomyocytes damage, may be related to inhibition of oxidative stress and depression of inflammative factors releasing.
Apoptosis
;
Cells, Cultured
;
Cytokines
;
metabolism
;
Glucose
;
adverse effects
;
Humans
;
Myocytes, Cardiac
;
cytology
;
pathology
;
Necrosis
;
Oxidative Stress
;
Reactive Oxygen Species
;
metabolism

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