MicroRNA miR-24-3p Reduces Apoptosis and Regulates Keap1-Nrf2 Pathway in Mouse Cardiomyocytes Responding to Ischemia/Reperfusion Injury

In recent years, microRNAs (miRNAs) have received increasing attention for their role in ischemia/reperfusion injury (I/RI), and many miRNAs have been demonstrated to play a very important role in cardiac I/RI. The miRNA miR-24-3p is a tumor suppressor that regulates multiple tumors; however, it remains unclear whether the expression level of miR-24-3p is altered in cardiac cells under I/RI. In this study, we used mouse primary cardiomyocytes and the H9C2 cardiomyocyte cell line to perform in vitro stimulated ischemia/reperfusion (SI/R) and then detected miR-24-3p expression level using quantitative real-time PCR (qRT-PCR). We discovered that the expression of miR-24-3p was significantly increased in cardiomyocytes following SI/R, and that the miR-24-3p level was inversely correlated to the ischemia marker HIF-1a. Furthermore, we transfected cardiomyocytes with miR-24-3p mimic or inhibitor to explore the role of miR-24-3p in cardiomyocyte ischemia/reperfusion injury in vitro. We performed flow cytometry to detect the apoptotic rate of H9C2 cardiomyocytes and found that the transfection of miR-24-3p mimic resulted in the decrease of the apoptosis rate of cardiomyocytes after SI/R, whereas the transfection of miR-24-3p inhibitor increased the number of apoptotic cardiomyocytes. These data suggest that the overexpression of miR-24-3p could reduce in vitro myocardial cell apoptosis induced by I/R injury. Finally, we applied the dual luciferase reporter gene system to verify whether miR-24-3p targets the Keap1 gene, and found that the luciferase signal intensity from a vector carrying the Keap1 wild-type reporter gene was significantly reduced after transfection with miR-24-3p mimic. The Keap1 protein level was also reduced following the transfection of miR-24-3p. The results from this study suggest a novel function of miR-24-3p in protecting cardiomyocytes from ischemia/reperfusion injury by the activation of the Nrf2-Keap1 pathway.

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The Ste20-like kinase SLK promotes p53 transactivation and apoptosis

AJP Renal Physiology ◽

10.1152/ajprenal.00294.2009 ◽

2009 ◽

Vol 297 (4) ◽

pp. F971-F980 ◽

Cited By ~ 13

Author(s):

Andrey V. Cybulsky ◽

Tomoko Takano ◽

Julie Guillemette ◽

Joan Papillon ◽

Rildo A. Volpini ◽

...

Keyword(s):

Reperfusion Injury ◽

Kidney Development ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Luciferase Reporter ◽

Enhancer Element ◽

Double Mutation ◽

Reporter Activity ◽

In Vitro Ischemia

Expression and activity of the germinal center SLK are increased during kidney development and recovery from renal ischemia-reperfusion injury. SLK promotes apoptosis, in part, via pathway(s) involving apoptosis signal-regulating kinase-1 and p38 mitogen-activated protein kinase. This study addresses the role of p53 as a potential effector of SLK. p53 transactivation was measured after transient transfection of a luciferase reporter plasmid that contains a p53 cis-acting enhancer element. Overexpression of SLK in COS-1 cells and cotransfection of SLK and p53-wild type (wt) cDNAs in glomerular epithelial cells (GECs) stimulated p53 transactivational activity, as measured by a p53 response element-driven luciferase reporter. In GECs, chemical anoxia followed by glucose reexposure (in vitro ischemia-reperfusion) increased p53 reporter activity, and this increase was amplified by overexpression of SLK. Expression of SLK induced p53 phosphorylation on serine (S)-33 and S315. In GECs, cotransfection of SLK with p53-wt, p53-S33A, p53-S315A, or p53-S33A+S315A mutants showed that only the double mutation abolished the SLK-induced increase in p53 reporter activity. SLK-induced stimulation of p53 reporter activity was attenuated by inhibition of JNK. Overexpression of SLK amplified apoptosis induced by subjecting cells to in vitro ischemia-reperfusion injury, while ectopic expression of a dominant negative SLK mutant attenuated the ischemia-reperfusion-induced apoptosis. The p53 transactivation inhibitor pifithrin-α significantly attenuated the amount of apoptosis after ischemia-reperfusion and SLK overexpression. Thus SLK induces p53 phosphorylation and transactivation, which enhances apoptosis after in vitro ischemia-reperfusion injury.

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Mir10a overexpression aggravates the renal ischemia-reperfusion injury associated with a decrease in PIK3CA

10.21203/rs.2.23453/v2 ◽

2020 ◽

Author(s):

Dongsheng Xu ◽

Wenjun Li ◽

Tao Zhang ◽

Gang Wang

Keyword(s):

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Luciferase Reporter ◽

Akt Pathway ◽

Luciferase Reporter Gene ◽

Gene Assay ◽

Underlying Mechanisms ◽

Related Proteins ◽

Hypoxia Reoxygenation

Abstract Background: To investigate the effect of miR-10a on the renal tissues with ischemia-reperfusion (I/R) injury in rats and explore the underlying mechanisms of miR-10a in the HK-2 cells of hypoxia-reoxygenation. Methods: The miR-10a level was measured in renal tissues with I/R rats by RT-PCR. In order to research the role of miR-10a in the renal tissues, miR-10 agonist and miR-10a antagonist were used to treat I/R rats. The levels of serum creatinine (Scr) and blood urea nitrogen (BUN) in serum, renal histopathology, apoptosis of cells in renal tissues were analyzed, separately. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway related proteins were measured by Western blot. The HK-2 cell was cultured to study the mechanism of miR-10a in the model of hypoxia-reoxygenation. The dual luciferase reporter gene assay was used to confirm the PI3K p100 catalytic subunit α (PIK3CA) was a target gene of miR-10a. Results: After renal I/R injury in rats, the miR-10a expression was significantly increased (p<0.05). Injection of miR-10a agonist significantly aggravated the injury of renal and raised the apoptosis of cells in renal in rats with renal I/R injury (p<0.05). However, administration of miR-10a antagonist obviously improved the injury of renal, decreased the renal cells apoptosis and inhibited the PI3K/Akt pathway activity (p<0.05). In vitro experiments, the negative relation between PIK3CA and miR-10a was confirmed. Further, overexpression of miR-10a significantly decreased the proliferation of HK-2 cells, and increased the cells apoptosis via up-regulating PI3K/Akt pathway (p<0.05). Conclusion: miR-10a could aggravate the renal I/R injury associated with a decrease in PIK3CA/PI3K/Akt pathway.

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Melatonin Attenuates Cardiac Ischemia-Reperfusion Injury through Modulation of IP3R-Mediated Mitochondria-ER Contact

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/1370862 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Wenya Li ◽

Botao Liu ◽

Lin Wang ◽

Jilie Liu ◽

Xiuhui Yang ◽

...

Keyword(s):

Reperfusion Injury ◽

Mitochondrial Permeability Transition ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Permeability Transition ◽

Cardiac Cells ◽

Mitochondrial Potential ◽

Rat Cardiomyocytes ◽

Postischemic Reperfusion

Although the interplay between mitochondria and ER has been identified as a crucial regulator of cellular homeostasis, the pathogenic impact of alterations in mitochondria-ER contact sites (MERCS) during myocardial postischemic reperfusion (I/R) injury remains incompletely understood. Therefore, in our study, we explored the beneficial role played by melatonin in protecting cardiomyocytes against reperfusion injury via stabilizing mitochondria-ER interaction. In vitro exposure of H9C2 rat cardiomyocytes to hypoxia/reoxygenation (H/R) augmented mitochondrial ROS synthesis, suppressed both mitochondrial potential and ATP generation, and increased the mitochondrial permeability transition pore (mPTP) opening rate. Furthermore, H/R exposure upregulated the protein content of CHOP and caspase-12, two markers of ER stress, and enhanced the transcription of main MERCS tethering proteins, namely, Fis1, BAP31, Mfn2, and IP3R. Interestingly, all the above changes could be attenuated or reversed by melatonin treatment. Suggesting that melatonin-induced cardioprotection works through normalization of mitochondria-ER interaction, overexpression of IP3R abolished the protective actions offered by melatonin on mitochondria-ER fitness. These results expand our knowledge on the cardioprotective actions of melatonin during myocardial postischemic reperfusion damage and suggest that novel, more effective treatments for acute myocardial reperfusion injury might be achieved through modulation of mitochondria-ER interaction in cardiac cells.

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microRNA-130a-5p suppresses myocardial ischemia reperfusion injury by downregulating the HMGB2/NF-κB axis

BMC Cardiovascular Disorders ◽

10.1186/s12872-020-01742-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yong Li ◽

Hongbo Zhang ◽

Zhanhu Li ◽

Xiaoju Yan ◽

Yuan Li ◽

...

Keyword(s):

Oxidative Stress ◽

Myocardial Ischemia ◽

Reperfusion Injury ◽

Mouse Models ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Luciferase Reporter ◽

Gene Assay ◽

Myocardial Ischemia Reperfusion Injury ◽

Myocardial Ischemia Reperfusion

Abstract Background Myocardial ischemia reperfusion injury (MIRI) is defined as tissue injury in the pathological process of progressive aggravation in ischemic myocardium after the occurrence of acute coronary artery occlusion. Research has documented the involvement of microRNAs (miRs) in MIRI. However, there is obscure information about the role of miR-130a-5p in MIRI. Herein, this study aims to investigate the effect of miR-130a-5p on MIRI. Methods MIRI mouse models were established. Then, the cardiac function and hemodynamics were detected using ultrasonography and multiconductive physiological recorder. Functional assays in miR-130a-5p were adopted to test the degrees of oxidative stress, mitochondrial functions, inflammation and apoptosis. Hematoxylin and eosin (HE) staining was performed to validate the myocardial injury in mice. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was employed to assess the expression patterns of miR-130a-5p, high mobility group box (HMGB)2 and NF-κB. Then, dual-luciferase reporter gene assay was performed to elucidate the targeting relation between miR-130a-5p and HMGB2. Results Disrupted structural arrangement in MIRI mouse models was evident from HE staining. RT-qPCR revealed that overexpressed miR-130a-5p alleviated MIRI, MIRI-induced oxidative stress and mitochondrial disorder in the mice. Next, the targeting relation between miR-130a-5p and HMGB2 was ascertained. Overexpressed HMGB2 annulled the protective effects of miR-130a-5p in MIRI mice. Additionally, miR-130a-5p targets HMGB2 to downregulate the nuclear factor kappa-B (NF-κB) axis, mitigating the inflammatory injury induced by MIRI. Conclusion Our study demonstrated that miR-130a-5p suppresses MIRI by down-regulating the HMGB2/NF-κB axis. This investigation may provide novel insights for development of MIRI treatments.

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N6-methyladenosine demethylase FTO impairs hepatic ischemia–reperfusion injury via inhibiting Drp1-mediated mitochondrial fragmentation

Cell Death and Disease ◽

10.1038/s41419-021-03622-x ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Ying Dong Du ◽

Wen Yuan Guo ◽

Cong Hui Han ◽

Ying Wang ◽

Xiao Song Chen ◽

...

Keyword(s):

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Mitochondrial Fragmentation ◽

Hepatic Ischemia ◽

Adeno Associated Virus ◽

Downstream Target ◽

Hepatic Ischemia Reperfusion

AbstractDespite N6-methyladenosine (m6A) is functionally important in various biological processes, its role and the underlying regulatory mechanism in the liver remain largely unexplored. In the present study, we showed that fat mass and obesity-associated protein (FTO, an m6A demethylase) was involved in mitochondrial function during hepatic ischemia–reperfusion injury (HIRI). We found that the expression of m6A demethylase FTO was decreased during HIRI. In contrast, the level of m6A methylated RNA was enhanced. Adeno-associated virus-mediated liver-specific overexpression of FTO (AAV8-TBG-FTO) ameliorated the HIRI, repressed the elevated level of m6A methylated RNA, and alleviated liver oxidative stress and mitochondrial fragmentation in vivo and in vitro. Moreover, dynamin-related protein 1 (Drp1) was a downstream target of FTO in the progression of HIRI. FTO contributed to the hepatic protective effect via demethylating the mRNA of Drp1 and impairing the Drp1-mediated mitochondrial fragmentation. Collectively, our findings demonstrated the functional importance of FTO-dependent hepatic m6A methylation during HIRI and provided valuable insights into the therapeutic mechanisms of FTO.

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The Sodium-Glucose Cotransporter-2 Inhibitor Canagliflozin Alleviates Endothelial Dysfunction Following In Vitro Vascular Ischemia/Reperfusion Injury in Rats

International Journal of Molecular Sciences ◽

10.3390/ijms22157774 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7774

Author(s):

Sevil Korkmaz-Icöz ◽

Cenk Kocer ◽

Alex A. Sayour ◽

Patricia Kraft ◽

Mona I. Benker ◽

...

Keyword(s):

Endothelial Dysfunction ◽

Reperfusion Injury ◽

Vascular Function ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Artery Bypass ◽

Diabetic Rats ◽

Organ Bath ◽

Sodium Glucose Cotransporter

Vascular ischemia/reperfusion injury (IRI) contributes to graft failure and adverse clinical outcomes following coronary artery bypass grafting. Sodium-glucose-cotransporter (SGLT)-2-inhibitors have been shown to protect against myocardial IRI, irrespective of diabetes. We hypothesized that adding canagliflozin (CANA) (an SGLT-2-inhibitor) to saline protects vascular grafts from IRI. Aortic rings from non-diabetic rats were isolated and immediately mounted in organ bath chambers (control, n = 9–10 rats) or underwent cold ischemic preservation in saline, supplemented either with a DMSO vehicle (IR, n = 8–10 rats) or 50µM CANA (IR + CANA, n = 9–11 rats). Vascular function was measured, the expression of 88 genes using PCR-array was analyzed, and feature selection using machine learning was applied. Impaired maximal vasorelaxation to acetylcholine in the IR-group compared to controls was significantly ameliorated by CANA (IR 31.7 ± 3.2% vs. IR + CANA 51.9 ± 2.5%, p < 0.05). IR altered the expression of 17 genes. Ccl2, Ccl3, Ccl4, CxCr4, Fos, Icam1, Il10, Il1a and Il1b have been found to have the highest interaction. Compared to controls, IR significantly upregulated the mRNA expressions of Il1a and Il6, which were reduced by 1.5- and 1.75-fold with CANA, respectively. CANA significantly prevented the upregulation of Cd40, downregulated NoxO1 gene expression, decreased ICAM-1 and nitrotyrosine, and increased PECAM-1 immunoreactivity. CANA alleviates endothelial dysfunction following IRI.

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Overexpression of SP1 restores autophagy to alleviate acute renal injury induced by ischemia-reperfusion through the miR-205/PTEN/Akt pathway

Journal of Inflammation ◽

10.1186/s12950-021-00270-y ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Chong Huang ◽

Yan Chen ◽

Bin Lai ◽

Yan-Xia Chen ◽

Cheng-Yun Xu ◽

...

Keyword(s):

Reperfusion Injury ◽

Cell Apoptosis ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Renal Ischemia ◽

Akt Pathway ◽

Acute Renal Injury ◽

Injury Model ◽

Renal Ischemia Reperfusion Injury

Abstract Background Acute kidney injury (AKI) is a major kidney disease with poor clinical outcome. SP1, a well-known transcription factor, plays a critical role in AKI and subsequent kidney repair through the regulation of various cell biologic processes. However, the underlying mechanism of SP1 in these pathological processes remain largely unknown. Methods An in vitro HK-2 cells with anoxia-reoxygenation injury model (In vitro simulated ischemic injury disease) and an in vivo rat renal ischemia-reperfusion injury model were used in this study. The expression levels of SP1, miR-205 and PTEN were detected by RT-qPCR, and the protein expression levels of SP1, p62, PTEN, AKT, p-AKT, LC3II, LC3I and Beclin-1 were assayed by western blot. Cell proliferation was assessed by MTT assay, and the cell apoptosis was detected by flow cytometry. The secretions of IL-6 and TNF-α were detected by ELISA. The targeted relationship between miR-205 and PTEN was confirmed by dual luciferase report assay. The expression and positioning of LC-3 were observed by immunofluorescence staining. TUNEL staining was used to detect cell apoptosis and immunohistochemical analysis was used to evaluate the expression of SP1 in renal tissue after ischemia-reperfusion injury in rats. Results The expression of PTEN was upregulated while SP1 and miR-205 were downregulated in renal ischemia-reperfusion injury. Overexpression of SP1 protected renal tubule cell against injury induced by ischemia-reperfusion via miR-205/PTEN/Akt pathway mediated autophagy. Overexpression of SP1 attenuated renal ischemia-reperfusion injury in rats. Conclusions SP1 overexpression restored autophagy to alleviate acute renal injury induced by ischemia-reperfusion through the miR-205/PTEN/Akt pathway.

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MiR-206 regulates the progression of osteoporosis via targeting HDAC4

European Journal of Medical Research ◽

10.1186/s40001-021-00480-3 ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Zhiyuan Lu ◽

Dawei Wang ◽

Xuming Wang ◽

Jilong Zou ◽

Jiabing Sun ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Apoptosis ◽

Diagnostic Value ◽

Expression Level ◽

Luciferase Reporter ◽

Control Group ◽

Luciferase Reporter Gene ◽

Mineral Density ◽

Gene Assay

Abstract Background More and more studies have confirmed that miRNAs play an important role in maintaining bone remodeling and bone metabolism. This study investigated the expression level of miR-206 in the serum of osteoporosis (OP) patients and explored the effect and mechanism of miR-206 on the occurrence and development of osteoporosis. Methods 120 postmenopausal women were recruited, including 63 cases with OP and 57 women without OP. The levels of miR-206 were determined by qRT-PCR technology. Spearman correlation coefficient was used to evaluate the correlation of miR-206 with bone mineral density (BMD). An ROC curve was used to evaluate the diagnostic value of miR-206 in osteoporosis. The effects of miR-206 on cell proliferation and cell apoptosis of hFOBs were measured by CCK-8 assay and flow cytometry, respectively. Luciferase reporter gene assay was used to confirm the interaction of miR-206 and the 3′UTR of HDAC4. Results Serum miR-206 had low expression level in osteoporosis patient group compared with control group. The expression level of serum miR-206 had diagnostic value for osteoporosis, and the serum miR-206 levels were positively correlated with BMD. The down-regulated miR-206 could inhibit cell proliferation and promote cell apoptosis. Luciferase analysis indicated that HDAC4 was the target gene of miR-206. Conclusions MiR-206 could be used as a new potential diagnostic biomarker for osteoporosis, and in in vitro cell experiments, miR-206 may regulate osteoblast cell proliferation and apoptosis by targeting HDAC4.

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