scholarly journals Circ_0030235 knockdown protects H9c2 cells against OGD/R-induced injury via regulation of miR-526b

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11482
Author(s):  
Yuquan Zhang ◽  
Shuzhu Liu ◽  
Limin Ding ◽  
Dawei Wang ◽  
Qiangqiang Li ◽  
...  

Backgrounds Acute myocardial infarction (MI) is the common clinical manifestation of coronary heart disease. Circular RNAs (circRNAs) act key roles in cardiomyocytes growth and angiogenesis. However, their functions in MI are not entirely clear. This research intended to investigate the role and underlying mechanisms of circ_0030235 in H9c2 cells. Methods H9c2 cells were conducted to oxygen glucose deprivation/reperfusion (OGD/R) inducement to establish the MI model. Circ_0030235 and miR-526b expression was tested and altered by qRT-PCR and transfection. Cell viability, apoptosis and reactive oxygen species (ROS) injury were tested by CCK-8 assay, TUNEL assay kit, and ROS Detection Assay Kit, respectively. Assessment of cell injury-related factors was performed by employing ELISA, Mitochondrial Viability Staining and the JC-1-Mitochondrial Membrane Potential Assay Kit. The relationship between circ_0030235 and miR-526b was analyzed by dual luciferase reporter assay. The expression of key proteins was analyzed by western blot. Results Circ_0030235 was highly expressed in OGD/R-induced H9c2 cells. OGD/R inducement cell viability, while accelerated apoptosis. Besides, the level ROS, cell injury-related factors, mitochondrial membrane potential were notably elevated by OGD/R inducement, while mitochondrial viability was remarkably declined. Whereas, these impacts were all noticeably remitted by circ_0030235 knockdown. miR-526b was a target of circ_0030235. Circ_0030235 knockdown-induced impacts were all notably abrogated by miR-526b inhibition, including the activating impacts on PI3K/AKT and MEK/ERK pathways. Conclusions This research implied that circ_0030235 knockdown might remit OGD/R-induced impacts via activation of PI3K/AKT and MEK/ERK pathways and regulation of miR-526b.

2019 ◽  
Vol 317 (6) ◽  
pp. G862-G871
Author(s):  
Amrita Ahluwalia ◽  
Neil Hoa ◽  
Michael K. Jones ◽  
Andrzej S. Tarnawski

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as diclofenac (DFN) and indomethacin (INDO) are extensively used worldwide. Their main side effects are injury of the gastrointestinal tract, including erosions, ulcers, and bleeding. Since gastric epithelial cells (GEPCs) are crucial for mucosal defense and are the major target of injury, we examined the extent to which DFN- and INDO-induced GEPC injury can be reversed by nerve growth factor (NGF), 16,16 dimethyl prostaglandin E2 (dmPGE2), and 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), the pharmacological activator of the metabolic sensor AMP kinase (AMPK). Cultured normal rat gastric mucosal epithelial (RGM1) cells were treated with PBS (control), NGF, dmPGE2, AICAR, and/or NSAID (DFN or INDO) for 1–4 h. We examined cell injury by confocal microscopy, cell death/survival using calcein AM, mitochondrial membrane potential using MitoTracker, and phosphorylation of AMPK by Western blotting. DFN and INDO treatment of RGM1 cells for 2 h decreased mitochondrial membrane potential and cell viability. NGF posttreatment (initiated 1 or 2 h after DFN or INDO) reversed the dissipation of mitochondrial membrane potential and cell injury caused by DFN and INDO and increased cell viability versus cells treated for 4 h with NSAID alone. Pretreatment with dmPGE2 and AICAR significantly protected these cells from DFN- and INDO-induced injury, whereas dmPGE2 and AICAR posttreatment (initiated 1 h after NSAID treatment) reversed cell injury and significantly increased cell viability and rescued the cells from NSAID-induced mitochondrial membrane potential reduction. DFN and INDO induce extensive mitochondrial injury and GEPC death, which can be significantly reversed by NGF, dmPGE2, and AICAR. NEW & NOTEWORTHY This study demonstrated that mitochondria are key targets of diclofenac- and indomethacin-induced injury of gastric epithelial cells and that diclofenac and indomethacin injury can be prevented and, importantly, also reversed by treatment with nerve growth factor, 16,16 dimethyl prostaglandin E2, and 5-aminoimidazole-4-carboxamide ribonucleotide.


2016 ◽  
Vol 94 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Yufeng Wang ◽  
Ligeng Zong ◽  
Xiaolei Wang

Background: Transforming growth factor-β (TGF-β) is known for its role in ventricular remodeling, inflammatory response, cell survival, and apoptosis. However, its role in improving myocardial function in rat hearts subjected to ischemia–reperfusion (I/R) and protecting against apoptosis induced in cardiomyocytes by anoxia–reoxygenation (A/R) has not been elucidated. This study investigated the protective effects and molecular mechanisms of TGF-β on myocardial function and cardiomyocyte apoptosis. Methods and results: We used TUNEL staining, we tested cell viability, and we measured mitochondrial membrane potential and levels of mitochondrial ROS after 6 h of simulated anoxia together with various durations of simulated reoxygenation in H9c2 cells. We further observed the contractile function in rat hearts after they were subjected to 30 min global ischemia and 180 min reperfusion. Pretreatment with TGF-β markedly inhibited apoptosis in H9c2 cells, as evidenced by increased cell viability and decreased numbers of TUNEL-positive cells, maintained mitochondrial membrane potential, and diminished mitochondrial production of reactive oxygen species (ROS). These changes were associated with the inhibition of endoplasmic reticulum (ER) stress-dependent markers of apoptosis (GRP78, CHOP, caspase-12, and JNK), and the modulation of the expression of Bcl2/Bax. Furthermore, TGF-β improved I/R-induced myocardial contractile dysfunction. All of these protective effects were concentration-dependent. Conclusion: Our results show that TGF-β prevents A/R-induced apoptosis of cardiomyocytes and improves myocardial function in rat hearts injured by I/R.


2019 ◽  
Vol 18 (4) ◽  
pp. 334-341 ◽  
Author(s):  
Kun Fu ◽  
Liqiang Chen ◽  
Lifeng Miao ◽  
Yan Guo ◽  
Wei Zhang ◽  
...  

Background/Objective: Grape seed proanthocyanidins (GSPs) are a group of polyphenolic bioflavonoids, which possess a variety of biological functions and pharmacological properties. We studied the neuroprotective effects of GSP against oxygen-glucose deprivation/reoxygenation (OGD/R) injury and the potential mechanisms in mouse neuroblastoma N2a cells. Methods: OGD/R was conducted in N2a cells. Cell viability was evaluated by CCK-8 and LDH release assay. Apoptosis was assessed by TUNEL staining and flow cytometry. Protein levels of cleaved caspase-3, Bax and Bcl-2 were detected by Western blotting. CHOP, GRP78 and caspase-12 mRNA levels were assessed by real-time PCR. JC-1 dying was used to detect mitochondrial membrane potential. ROS levels, activities of endogenous antioxidant enzymes and ATP production were examined to evaluate mitochondrial function. Results: GSP increased cell viability after OGD/R injury in a dose-dependent manner. Furthermore, GSP inhibited cell apoptosis, reduced the mRNA levels of CHOP, GRP78 and caspase-12 (ER stressassociated genes), restored mitochondrial membrane potential and ATP generation, improved activities of endogenous anti-oxidant ability (T-AOC, GXH-Px, and SOD), and decreased ROS level. Conclusion: Our findings suggest that GSP can protect N2a cells from OGD/R insult. The mechanism of anti-apoptotic effects of GSP may involve attenuating ER stress and mitochondrial dysfunction.


2007 ◽  
Vol 28 (5) ◽  
pp. 1009-1016 ◽  
Author(s):  
Ludmila A Voloboueva ◽  
Melissa Duan ◽  
YiBing Ouyang ◽  
John F Emery ◽  
Christian Stoy ◽  
...  

Mitochondrial heat shock protein 70 (mtHsp70/Hsp75/Grp75/mortalin/TRAP-1/PBP74) is an essential mitochondrial chaperone and a member of the heat shock protein 70 (HSP70) family. Although many studies have shown the protective properties of overexpression of the cytosolic inducible member of the HSP70 family, Hsp72, few studies have investigated the protective potential of Hsp75 against ischemic injury. Mitochondria are one of the primary targets of ischemic injury in astrocytes. In this study, we analyzed the effects of Hsp75 overexpression on cellular levels of reactive oxygen species (ROS), mitochondrial membrane potential, ATP levels, and viability during the ischemia-like conditions of oxygen-glucose deprivation (OGD) or glucose deprivation (GD) in primary astrocytic cultures. We show that Hsp75 overexpression decreases ROS production and preserves mitochondrial membrane potential during GD, and preserves ATP levels and cell viability during OGD. These findings indicate that Hsp75 can provide protection against ischemia-like in vitro injury and suggest that it should be further studied as a potential candidate for protection against ischemic injury.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4582-4582 ◽  
Author(s):  
Wendy J. Freebern ◽  
Hengsheng S. Fang ◽  
Martin D. Slade ◽  
Susan Wells ◽  
Jennifer Canale ◽  
...  

Abstract Tyrosine kinase inhibitors (TKI) selective for Bcr-Abl, such as dasatinib, imatinib, and nilotinib have had remarkable success in the clinic, potentially shifting the prognosis of chronic myelogenous leukemia (CML) to a manageable chronic disease. With the increase in longevity of CML patients, there is rising concern of co-morbidities that may be influenced by chemotherapy (Force et al., Nature Rev.2007;7:332–340). Recently, congestive heart failure (CHF) and direct cellular cardiotoxicity have been reported in CML patients on imatinib therapy (Kerkela et al., Nature Medicine2006;12:908–916). Ultrastructural mitochondrial abnormalities in cardiomyocytes were observed in CML patients with severe CHF and, interestingly, similar abnormalities were observed in cardiomyocytes of imatinib-treated mice, thus providing a prospective in vivo animal model for imatinib-induced cardiotoxicity. Furthermore, correlative findings of mitochondrial membrane potential loss, decreased cell viability, and increased apoptosis resulted from an array of cell-based assays in imatinib-treated primary rat cardiomyocytes, consequentially affording a supportive, if not predictive, in vitro cardiomyocyte toxicity model. Since imatinib-induced inhibition of the native form of c-Abl kinase was speculated to cause the observed cardiotoxicity and c-Abl is a shared target of dasatinib, imatinib, and nilotinib, the in vitro cardiotoxicity potential of dasatinib and nilotinib at pharmacologically relevant concentrations (0.09 μM and 5 μM, respectively) and up to 10-fold higher concentrations were compared side-by-side with imatinib in primary rat cardiomyocytes. Dasatinib did not significantly affect mitochondrial membrane potential, cell viability, apoptosis, or cellular ultrastructure in vitro, whereas imatinib significantly affected these parameters. Nilotinib at pharmacologically relevant concentration demonstrated decreased cell viability, but differed from imatinib in that mitochondrial membrane potential integrity was not affected under identical experimental conditions. Results suggest that at pharmacologically relevant concentrations, dasatinib does not induce cardiotoxicity, as does imatinib and nilotinib, and the molecular mechanisms of the observed cardiotoxicities may differ between imatinib and nilotinib. Of indirect relation, results from assessing another cardiovascular liability, namely hERG K+ channel blockade, demonstrated that dasatinib, imatinib and nilotinib differentially inhibited the hERG currents in vitro with IC50 of 14.3, 15.6 and 0.66 μM, respectively. These in vitro findings occurred at concentration levels approximately 150, 3 and 0.1-fold the expected human Cmax for the three TKIs, respectively. Thus, although TKI therapies may share similar targeting and clinical indications, differentiating specific toxicity profiles may be predictive of differences in potential clinical adversities.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5558-5558
Author(s):  
Jishi Wang ◽  
Wei Sixi ◽  
Wang Yating ◽  
Chai Qixiang

Abstract Aim Using lentivirus-mediated HO-1 siRNA (lenti-siHO-1-GFP) to silence the HO-1 gene in Kasumi cells so as to explore the role and mechanism of HO-1 on cell apoptosis. Methods To infect Kasumi cells with lenti-siHO-1-GFP and check the infection efficiency by using fluorescence microscopy and flow cytometry (FCM). Experimental group was divided into three groups: untreated Kasumi (K), infected Kasumi by empty vector (lenti-GFP-K) and infected Kasumi by lentivirus-mediated HO-1 siRNA (lenti-siHO-1-K). The HO-1 expression of each group was detected by realtime PCR. Fluo3-AM method was used to detect the intracellular Ca2+ accumulation. DCFH-DA was used for the measurement of intracellular ROS. The change of mitochondrial membrane potential was evaluated by JC-1 stainning by using FCM. After being treated with various concentrations of daunorubicin for 24, 48, and 72 h respectively, cell viability was determined by MTT assay. Cell apoptosis was determined by FCM following with cells dual-stained with Annexin-V-FITC and propidium iodide (PI). The mRNA of HO-1 and apoptosis-related genes were analyzed by realtime PCR and, the expressions of their corresponding protein were determined by western blot. Additionally, After treating with 10mM Ca2+chelator BAPTA-AM and 0.5mM NAC for 12h, Ca2+ accumulation, ROS generation, the expression of HO-1 and apoptosis-related genes were detected respectively. Result presented in mean±sd manner. Results After lenti-siHO-1-GFP infection for 48h, we could observe the fluorescence clear, the fluorescent intensity was 95.87% after 72 hours. The HO-1 silencing efficiency of lenti-siHO-1-K was 77.00%. MTT result showed that daunorubicin exerted moderate inhibitory effects on cell proliferation in a dose and time dependent manner. With the same treating conditions, the cell viability of lenti-siHO-1-K group was significantly lower than the other two groups(e.g 49.20±1.30% survival in lenti-siHO-1-K group, 72.40±1.90% in K group and 74.10±2.10% in lenti-GFP-K group after being treated by 5ug/ml DNR,respectively, p=0.014), while the apoptosis rate was higher than the other two groups(e.g 75.77±3.41% in lenti-siHO-1-K group, 23.72±2.03% in K group and 26.10±1.95% in lenti-GFP-K group after being treated by 5ug/ml DNR,respectively, p=0.011). Compared with other two groups, the lenti-siHO-1-K group showed a downregulation in the mRNA and protein expression of HO-1. The mRNA and protein expressions of cyto-C, caspase3, caspase8, caspase9 and caspase12 in lenti-siHO-1-K group were upregulated after exposure to 5ug/ml daunorubicin for 24 hours. Compared with K and lenti-GFP-K groups, Ca2+ accumulation in lenti-siHO-1-K group was increased significantly(e.g 40.35±2.10% in lenti-siHO-1-K group, 17.30±1.81% in K group and 14.15±1.75% in lenti-GFP-K group,respectively, p=0.041). The ROS generation was higher than the other two groups(e.g 47.65±2.05% in lenti-siHO-1-K group, 21.30±1.94% in K group and19.90±2.01% in lenti-GFP-K group,respectively, p=0.037). The ratio of Green/Red fluorescence intensity increased significantly in lenti-siHO-1-K group(e.g 0.704±0.06 in lenti-siHO-1-K group, 0.57±0.09 in K group and 0.527±0.05 in lenti-GFP-K group, respectively, p=0.042). After exposure to 10mM BAPTA-AM and 0.1mM NAC alone or combined with, both the intracellular Ca2+accumulation and the ROS level in lenti-siHO-1-K group reduced(17.59±1.01% of Ca2+acumulation and 19.78±1.3% of ROS production after BAPTA-AM treatment alone, 23.42±1.97% of Ca2+and 15.47±1.14% of ROS after being treated by NAC alone, 16.52±1.23% of Ca2+and 14.37±1.21% of ROS after treatment by both agent) , while the mRNA and protein expressions of cyto-C, caspase3, caspase8, caspase9 and caspase12, decreased significantly. Conclusion HO-1 gene silencing played a role in pro-apoptosis in Kasumi cells. The mechanism may be related to the endoplasmic reticulum stress and abnormal accumulation of intracellular Ca2+, ROS generation, descending of the mitochondrial membrane potential and release cyto-C, then further activated the caspases cascade and promoted apoptosis. However, it tended to be initiated by crosstalk in Ca2+-ROS pathway. Disclosures: No relevant conflicts of interest to declare.


2001 ◽  
Vol 281 (3) ◽  
pp. H1295-H1303 ◽  
Author(s):  
Meifeng Xu ◽  
Yigang Wang ◽  
Ahmar Ayub ◽  
Muhammad Ashraf

Mitochondrial membrane potential (ΔΨm) is severely compromised in the myocardium after ischemia-reperfusion and triggers apoptotic events leading to cell demise. This study tests the hypothesis that mitochondrial ATP-sensitive K+ (mitoKATP) channel activation prevents the collapse of ΔΨm in myocytes during anoxia-reoxygenation (A-R) and is responsible for cell protection via inhibition of apoptosis. After 3-h anoxia and 2-h reoxygenation, the cultured myocytes underwent extensive damage, as evidenced by decreased cell viability, compromised membrane permeability, increased apoptosis, and decreased ATP concentration. Mitochondria in A-R myocytes were swollen and fuzzy as shown after staining with Mito Tracker Orange CMTMRos and in an electron microscope and exhibited a collapsed ΔΨm, as monitored by 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolcarbocyanine iodide (JC-1). Cytochrome c was released from mitochondria into the cytosol as demonstrated by cytochrome cimmunostaining. Activation of mitoKATP channel with diazoxide (100 μmol/l) resulted in a significant protection against mitochondrial damage, ATP depletion, cytochrome c loss, and stabilized ΔΨm. This protection was blocked by 5-hydroxydecanoate (500 μmol/l), a mitoKATPchannel-selective inhibitor, but not by HMR-1098 (30 μmol/l), a putative sarcolemmal KATP channel-selective inhibitor. Dissipation of ΔΨm also leads to opening of mitochondrial permeability transition pore, which was prevented by cyclosporin A. The data support the hypothesis that A-R disrupts ΔΨm and induces apoptosis, which are prevented by the activation of the mitoKATP channel. This further emphasizes the therapeutic significance of mitoKATP channel agonists in the prevention of ischemia-reperfusion cell injury.


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