1
|
Xu P, Jin K, Zhou J, Gu J, Gu X, Dong L, Sun X. G9a inhibition promotes the formation of pacemaker-like cells by reducing the enrichment of H3K9me2 in the HCN4 promoter region. Mol Med Rep 2022; 27:21. [PMID: 36484369 PMCID: PMC9813554 DOI: 10.3892/mmr.2022.12908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 11/04/2022] [Indexed: 12/12/2022] Open
Abstract
Biological pacemakers, made of pacemaker-like cells, are promising in the treatment of bradyarrhythmia; however, the inefficiency of stem cell differentiation into pacemaker-like cells has limited their clinical application. Previous studies have reported that histone H3 at lysine 9 (H3K9) methylation is widely involved in the proliferation and differentiation of cardiomyocytes, but the specific role of H3K9 dimethylation (H3K9me2) in the formation of pacemaker cells remains unclear. The present study evaluated the functional role of H3K9me2 in the differentiation of bone marrow mesenchymal stem cells (BMSCs) into pacemaker-like cells. Rat BMSCs pretreated with the euchromatic histone lysine methyltransferase 2 (G9a) inhibitor BIX01294 were transfected with a T-box 18 overexpression plasmid to induce BMSCs to form pacemaker-like cells. The induced pacemaker-like cells were analyzed using reverse transcription-quantitative PCR (RT-qPCR) and immunofluorescence to assess the efficiency of differentiation. The enrichment of H3K9me2 in the hyperpolarized-activated cyclic nucleotide-gated cation channel (HCN)4 promoter region was assessed by chromatin immunoprecipitation (ChIP). In addition, BIX01294 was injected into rats, and the protein and mRNA expression levels of HCN4 were assessed using western blotting and RT-qPCR. After interference with G9a using BIX01294, ChIP results demonstrated that H3K9me2 levels in the promoter region of HCN4 were markedly decreased. Immunofluorescence and RT-qPCR demonstrated that the protein expression levels of certain cardio-specific proteins in the treated group were significantly higher compared with those in the untreated group. In vivo experiments demonstrated that interference with G9a could cause pathological hypertrophy. Furthermore, in vitro and in vivo inhibition of G9a could increase the differentiation and proliferation of pacemaker-like cells by decreasing the levels of H3K9me2 in the promoter region of HCN4 gene.
Collapse
Affiliation(s)
- Pei Xu
- Department of Haematology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China
| | - Kai Jin
- Department of Cardiology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China
| | - Jing Zhou
- College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Jiangun Gu
- Department of Cardiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Xiang Gu
- Department of Cardiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Lijuan Dong
- Department of Cardiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Xiaolin Sun
- Department of Cardiology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China,Correspondence to: Dr Xiaolin Sun, Department of Cardiology, Taizhou People's Hospital, 366 Taihu Road, Taizhou, Jiangsu 225300, P.R. China, E-mail:
| |
Collapse
|
2
|
Sun X, Gu X, Li H, Xu P, Li M, Zhu Y, Zuo Q, Li B. H3K9me2 regulates early transcription factors to promote mesenchymal stem‑cell differentiation into cardiomyocytes. Mol Med Rep 2021; 24:616. [PMID: 34184085 DOI: 10.3892/mmr.2021.12255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 05/24/2021] [Indexed: 11/05/2022] Open
Abstract
Studies have shown that histone H3 at lysine 9 (H3K9me2) is an important epigenetic modifier of embryonic development, cell reprogramming and cell differentiation, but its specific role in cardiomyocyte formation remains to be elucidated. The present study established a model of 5‑Azacytidine‑induced differentiation of rat bone mesenchymal stem cells (MSCs) into cardiomyocytes and, on this basis, investigated the dimethylation of H3K9me2 and its effect on cardiomyocyte formation by knockdown of H3K9me2 methylase, euchromatic histone‑lysine N‑methyltransferase 2 (G9a) and H3K9me2 lysine demethylase 3A (KDM3A). The results demonstrated that, in comparison with the normal induction process, the knockdown of G9a could significantly reduce the H3K9me2 level of the MSCs in the induced model. Reverse transcription‑quantitative (RT‑q) PCR demonstrated that the expression of cardiac troponin T(cTnT) was significantly increased. In addition, flow cytometry demonstrated that the proportion of cTnT‑positive cells was significantly increased on day 21. With the knockdown of KDM3A, the opposite occurred. In order to explore the specific way of H3K9me2 regulating cardiomyocyte formation, western blotting and RT‑qPCR were used to detect the expression of key transcription factors including GATA binding protein 4 (GATA‑4), NK2 Homeobox 5 (Nkx2.5) and myocyte enhancer factor 2c (MEF2c) during cardiomyocyte formation. The decrease of H3K9me2 increased the expression of transcription factors GATA‑4, Nkx2.5 and MEF2c in the early stage of myocardial development while the increase of H3K9me2 inhibited the expression of those transcription factors. Accordingly, it was concluded that H3K9me2 is a negative regulator of cardiomyocyte formation and can participate in cardiomyocyte formation by activating or inhibiting key transcription factors of cardiomyocytes, which will lay the foundation for the optimized induction efficiency of cardiomyocytes in in vitro and clinical applications.
Collapse
Affiliation(s)
- Xiaolin Sun
- Department of Cardiology, Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Xiang Gu
- Department of Cardiology, Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Hongxiao Li
- Department of Cardiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Pei Xu
- Department of Hematology, Taizhou People's Hospital, Taizhou, Jiangsu 225300, P.R. China
| | - Mengting Li
- Department of Cardiology, Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Ye Zhu
- Department of Cardiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Qisheng Zuo
- Key Laboratory of Animal Breeding and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Bichun Li
- Key Laboratory of Animal Breeding and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| |
Collapse
|
3
|
Acetyl-CoA Metabolism and Histone Acetylation in the Regulation of Aging and Lifespan. Antioxidants (Basel) 2021; 10:antiox10040572. [PMID: 33917812 PMCID: PMC8068152 DOI: 10.3390/antiox10040572] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/31/2021] [Accepted: 04/02/2021] [Indexed: 12/16/2022] Open
Abstract
Acetyl-CoA is a metabolite at the crossroads of central metabolism and the substrate of histone acetyltransferases regulating gene expression. In many tissues fasting or lifespan extending calorie restriction (CR) decreases glucose-derived metabolic flux through ATP-citrate lyase (ACLY) to reduce cytoplasmic acetyl-CoA levels to decrease activity of the p300 histone acetyltransferase (HAT) stimulating pro-longevity autophagy. Because of this, compounds that decrease cytoplasmic acetyl-CoA have been described as CR mimetics. But few authors have highlighted the potential longevity promoting roles of nuclear acetyl-CoA. For example, increasing nuclear acetyl-CoA levels increases histone acetylation and administration of class I histone deacetylase (HDAC) inhibitors increases longevity through increased histone acetylation. Therefore, increased nuclear acetyl-CoA likely plays an important role in promoting longevity. Although cytoplasmic acetyl-CoA synthetase 2 (ACSS2) promotes aging by decreasing autophagy in some peripheral tissues, increased glial AMPK activity or neuronal differentiation can stimulate ACSS2 nuclear translocation and chromatin association. ACSS2 nuclear translocation can result in increased activity of CREB binding protein (CBP), p300/CBP-associated factor (PCAF), and other HATs to increase histone acetylation on the promoter of neuroprotective genes including transcription factor EB (TFEB) target genes resulting in increased lysosomal biogenesis and autophagy. Much of what is known regarding acetyl-CoA metabolism and aging has come from pioneering studies with yeast, fruit flies, and nematodes. These studies have identified evolutionary conserved roles for histone acetylation in promoting longevity. Future studies should focus on the role of nuclear acetyl-CoA and histone acetylation in the control of hypothalamic inflammation, an important driver of organismal aging.
Collapse
|
4
|
Sung PH, Luo CW, Chiang JY, Yip HK. The combination of G9a histone methyltransferase inhibitors with erythropoietin protects heart against damage from acute myocardial infarction. Am J Transl Res 2020; 12:3255-3271. [PMID: 32774698 PMCID: PMC7407701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 06/03/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND This study tested the hypothesis that combined histone methyltransferase G9a inhibitor (i.e., UNC0638) and erythropoietin (EPO) was superior to either one alone for protecting myocardium from acute myocardial infarction (AMI) damage. METHODS AND RESULTS Adult-male SD rats (n=30) were equally categorized into group 1 (sham-operated control), group 2 (AMI), group 3 (AMI-EPO/1000 IU/kg, I.M./3 h after AMI), group 4 (AMI- UNC0638/5 mg/kg I.P./3 h after AMI) and group 5 [AMI-UNC0638-EPO 3 h after AMI] treatment. Animals were euthanized at day 21 after AMI induction. By day 21, left-ventricular-ejection-fraction (LVEF) was highest in group 1, lowest in group 2, significantly higher in group 5 than in groups 3 and 4, but no difference between the latter two groups (all P<0.0001). The protein expressions of inflammatory (MMP-2/MM-9), fibrotic (fibronectin/Smad3/TGF-ß), apoptotic/DNA-damaged (caspas-3/PARP/γ-H2AX), cell-stress response (HIF-1α/p-Akt/p-mTOR) and autophagic (beclin-1/ratio of LC3B-II to LC3B-I) biomarkers exhibited an opposite pattern, whereas the protein expressions of endothelial integrity (CD31/vWF) and anti-oxidant (SIRT1/SIRT3) exhibited an identical pattern of LVEF among the five groups (all P<0.0001). The protein expressions (SDF-1α/VEGF/CXCR4) and cellular expressions (C-kit/CD31+//Sca-1/CD31+//KDR/CD34+) of angiogenesis biomarkers were significantly progressively increased from groups 1 to 5 (all P<0.0001). The infarction/fibrotic areas, myocyte size and number of G9a cells exhibited an opposite pattern, whereas the small-vessel density displayed an identical trend of LVEF among the groups (all P<0.0001). Flow cytometric analysis showed cellular levels of inflammation (Ly6G+/MPO+/CD11b/c+), oxidative-stress (DCFDA+) and apoptosis (early+/late+) exhibited an opposite pattern to LVEF among the groups (all P<0.0001). CONCLUSION EPO-BIX01294 effectively protected myocardium against AMI-induced damage.
Collapse
Affiliation(s)
- Pei-Hsun Sung
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of MedicineKaohsiung 83301, Taiwan, ROC
- Center for Shockwave Medicine and Tissue Engineering, Kaohsiung Chang Gung Memorial HospitalKaohsiung 83301, Taiwan, ROC
| | - Chi-Wen Luo
- Department of Surgery, Kaohsiung Medical University HospitalKaohsiung 80708, Taiwan, ROC
- Division of Breast Surgery, Department of Surgery, Kaohsiung Medical University HospitalKaohsiung 80708, Taiwan, ROC
| | - John Y Chiang
- Department of Computer Science and Engineering, National Sun Yat-Sen UniversityKaohsiung 80424, Taiwan, ROC
- Department of Healthcare Administration and Medical Informatics, Kaohsiung Medical UniversityKaohsiung 80708, Taiwan, ROC
| | - Hon-Kan Yip
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of MedicineKaohsiung 83301, Taiwan, ROC
- Center for Shockwave Medicine and Tissue Engineering, Kaohsiung Chang Gung Memorial HospitalKaohsiung 83301, Taiwan, ROC
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial HospitalKaohsiung 83301, Taiwan, ROC
- Department of Medical Research, China Medical University Hospital, China Medical UniversityTaichung, Taiwan 40402, ROC
- Department of Nursing, Asia UniversityTaichung 41354, Taiwan, ROC
- Division of Cardiology, Department of Internal Medicine, Xiamen Chang Gung HospitalXiamen, Fujian, China
| |
Collapse
|