ABSTRACT
Long non-coding RNAs (lncRNAs) have been widely recognized as important regulators in myocardial infarction (MI) and other heart diseases. Our study aimed to investigate the mechanism and biological function of an unknown lncRNA zinc finger protein 561 antisense RNA 1 (ZNF561-AS1) in MI. After confirming the MI model was successful, we applied reverse transcription quantitative polymerase chain reaction and Western blot (WB) and found that the expression of NLR family pyrin domain containing 3 (NLRP3), interleukin (IL)-1ß, and IL-18 was substantially increased in infarct and border zones of MI mice heart at 24 h and 72 h compared with that in sham-operated models. Moreover, we found that NLRP3 expression was promoted in hypoxia human cardiomyocytes (HCMs). Through cell function assays including CCK-8, 5-Ethynyl-2'-deoxyuridine (EdU), flow cytometry, and TdT-mediated dUTP Nick-End Labeling (TUNEL), supported by WB analysis, we verified that silencing of NLRP3 facilitated proliferation but impeded apoptosis of hypoxia-induced myocardial cell. Moreover, Ago2-RIP and RNA pull-down assays displayed that NLRP3 could combine with miR-223-3p. Luciferase reporter assays further confirmed that NLRP3 was directly targeted by miR-223-3p. Simultaneously, we found that miR-223-3p was the downstream gene of ZNF561-AS1. In addition, we conducted a series of rescue experiments to affirm that ZNF561-AS1 regulated cell proliferation and apoptosis in MI through miR-223-3p/NLRP3 axis.
Subject(s)
MicroRNAs , Myocardial Infarction , RNA, Long Noncoding , Animals , Apoptosis/genetics , Cell Proliferation/genetics , Humans , Hypoxia , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Myocardial Infarction/genetics , Myocardial Infarction/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolismABSTRACT
BACKGROUND: Transforming growth factor-ß (TGF-ß) 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-ß 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-ß 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-ß improved I/R-induced myocardial contractile dysfunction. All of these protective effects were concentration-dependent. CONCLUSION: Our results show that TGF-ß prevents A/R-induced apoptosis of cardiomyocytes and improves myocardial function in rat hearts injured by I/R.
Subject(s)
Heart/drug effects , Myocardial Reperfusion Injury/drug therapy , Myocytes, Cardiac/drug effects , Transforming Growth Factor beta/pharmacology , Animals , Apoptosis/drug effects , Caspase 3/metabolism , Caspase Inhibitors/pharmacology , Cell Line , Endoplasmic Reticulum Stress/drug effects , Heart/physiology , Membrane Potential, Mitochondrial/drug effects , Myocardial Reperfusion Injury/pathology , Myocardial Reperfusion Injury/physiopathology , Myocytes, Cardiac/cytology , Myocytes, Cardiac/physiology , Rats , Reactive Oxygen Species/metabolism , Recombinant Proteins/pharmacologyABSTRACT
This study aimed to screen the potential diagnostic biomarkers for distinguishing the malignant pheochromocytoma (PCC) from benign PCC. A total of 59 patients with PCC (benign and malignant) were enrolled in this study. The expression level of miRNAs in patients with different kind PCCs (healthy control, benign, malignant, malignant with or without SDHD mutation, adrenal and extra-adrenal) was analyzed using the qRT-PCR analysis. Besides, the diagnosis accuracy of miRNA in PCC samples was analyzed using the ROC analysis. Moreover, level of miR-101 in serum was detected by qRT-PCR analysis and serum VEGF level in patients with PCC was detected using the ELISA kit. Compared with benign PCC, miR-101 level was higher in patients with malignant PCC (P < 0.05), while the level of miR-513-5p and miR-26b showed no difference between malignant PCC and benign PCC (P > 0.05). miR-101 expression was significantly increased in malignant tumor tissue with SDHD mutation (P < 0.05) and in extra-adrenal tissues (P < 0.05), respectively. Besides, AUCs for miR-101 in PCC samples was 0.79 and for which in PCC samples with non-SDHD mutation was 0.77. Besides, serum miR-101 in malignant PCC was high but showed no difference among groups (P > 0.05). Moreover, serum VEGF level in malignant tumors was significantly high compared with benign tumor, as well as that in malignant PCC with SDHD mutation (P < 0.05). Our study suggested that SDHD mutation may enhance the overexpression of miR-101 in malignant tumors and miR-101 may be a potential diagnostic biomarker for malignant PCC and benign PCC.
