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Du Y, Li J, Dai Z, Chen Y, Zhao Y, Liu X, Xia T, Zhu P, Wang Y. Pyruvate kinase M2 sustains cardiac mitochondrial quality surveillance in septic cardiomyopathy by regulating prohibitin 2 abundance via S91 phosphorylation. Cell Mol Life Sci 2024; 81:254. [PMID: 38856931 DOI: 10.1007/s00018-024-05253-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 04/11/2024] [Accepted: 04/20/2024] [Indexed: 06/11/2024]
Abstract
The endogenous mitochondrial quality control (MQC) system serves to protect mitochondria against cellular stressors. Although mitochondrial dysfunction contributes to cardiac damage during many pathological conditions, the regulatory signals influencing MQC disruption during septic cardiomyopathy (SC) remain unclear. This study aimed to investigate the involvement of pyruvate kinase M2 (PKM2) and prohibitin 2 (PHB2) interaction followed by MQC impairment in the pathogenesis of SC. We utilized LPS-induced SC models in PKM2 transgenic (PKM2TG) mice, PHB2S91D-knockin mice, and PKM2-overexpressing HL-1 cardiomyocytes. After LPS-induced SC, cardiac PKM2 expression was significantly downregulated in wild-type mice, whereas PKM2 overexpression in vivo sustained heart function, suppressed myocardial inflammation, and attenuated cardiomyocyte death. PKM2 overexpression relieved sepsis-related mitochondrial damage via MQC normalization, evidenced by balanced mitochondrial fission/fusion, activated mitophagy, restored mitochondrial biogenesis, and inhibited mitochondrial unfolded protein response. Docking simulations, co-IP, and domain deletion mutant protein transfection experiments showed that PKM2 phosphorylates PHB2 at Ser91, preventing LPS-mediated PHB2 degradation. Additionally, the A domain of PKM2 and the PHB domain of PHB2 are required for PKM2-PHB2 binding and PHB2 phosphorylation. After LPS exposure, expression of a phosphorylation-defective PHB2S91A mutant negated the protective effects of PKM2 overexpression. Moreover, knockin mice expressing a phosphorylation-mimetic PHB2S91D mutant showed improved heart function, reduced inflammation, and preserved mitochondrial function following sepsis induction. Abundant PKM2 expression is a prerequisite to sustain PKM2-PHB2 interaction which is a key element for preservation of PHB2 phosphorylation and MQC, presenting novel interventive targets for the treatment of septic cardiomyopathy.
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Affiliation(s)
- Yingzhen Du
- The Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| | - Jialei Li
- School of Medicine, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhe Dai
- School of Medicine, Southern Medical University, Guangzhou, Guangdong, China
| | - Yuxin Chen
- School of Medicine, Southern Medical University, Guangzhou, Guangdong, China
| | - Yao Zhao
- School of Medicine, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiaoman Liu
- School of Medicine, Southern Medical University, Guangzhou, Guangdong, China
| | - Tian Xia
- Department of Clinical Laboratory Medicine, The First Medical Centre, Medical School of Chinese People's Liberation Army, Beijing, China
- Xianning Medical College, Hubei University of Science & Technology, Xianning, China
| | - Pingjun Zhu
- The Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Medical School of Chinese PLA, Beijing, China.
| | - Yijin Wang
- The Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Medical School of Chinese PLA, Beijing, China.
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Liu N, Ding Y, Zhou H, Chang X, Lou L. Dual-specificity phosphatase 1 interacts with prohibitin 2 to improve mitochondrial quality control against type-3 cardiorenal syndrome. Int J Med Sci 2024; 21:547-561. [PMID: 38322592 PMCID: PMC10845262 DOI: 10.7150/ijms.90484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 12/22/2023] [Indexed: 02/08/2024] Open
Abstract
Type-3 cardiorenal syndrome (CRS-3) is acute kidney injury followed by cardiac injury/dysfunction. Mitochondrial injury may impair myocardial function during CRS-3. Since dual-specificity phosphatase 1 (DUSP1) and prohibitin 2 (PHB2) both promote cardiac mitochondrial quality control, we assessed whether these proteins were dysregulated during CRS-3-related cardiac depression. We found that DUSP1 was downregulated in heart tissues from a mouse model of CRS-3. DUSP1 transgenic (DUSP1Tg) mice were protected from CRS-3-induced myocardial damage, as evidenced by their improved heart function and myocardial structure. CRS-3 induced the inflammatory response, oxidative stress and mitochondrial dysfunction in wild-type hearts, but not in DUSP1Tg hearts. DUSP1 overexpression normalized cardiac mitochondrial quality control during CRS-3 by suppressing mitochondrial fission, restoring mitochondrial fusion, re-activating mitophagy and augmenting mitochondrial biogenesis. We found that DUSP1 sustained cardiac mitochondrial quality control by binding directly to PHB2 and maintaining PHB2 phosphorylation, while CRS-3 disrupted this physiological interaction. Transgenic knock-in mice carrying the Phb2S91D variant were less susceptible to cardiac depression upon CRS-3, due to a reduced inflammatory response, suppressed oxidative stress and improved mitochondrial quality control in their heart tissues. Thus, CRS-3-induced myocardial dysfunction can be attributed to reduced DUSP1 expression and disrupted DUSP1/PHB2 binding, leading to defective cardiac mitochondrial quality control.
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Affiliation(s)
- Nanyang Liu
- Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yanqiu Ding
- Graduate School, Beijing University of Chinese Medicine, Beijing, China
| | - Hao Zhou
- Graduate School, Beijing University of Chinese Medicine, Beijing, China
| | - Xing Chang
- Cardiovascular department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Long Lou
- Kunming Municipal Hospital of Traditional Chinese Medicine, Yunnan, China
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3
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Zeng Z, Qiu J, Chen Y, Liang D, Wei F, Fu Y, Zhang J, Wei X, Zhang X, Tao J, Lin L, Zheng J. Altered Gut Microbiota as a Potential Risk Factor for Coronary Artery Disease in Diabetes: A Two-Sample Bi-Directional Mendelian Randomization Study. Int J Med Sci 2024; 21:376-395. [PMID: 38169662 PMCID: PMC10758148 DOI: 10.7150/ijms.92131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 12/08/2023] [Indexed: 01/05/2024] Open
Abstract
The current body of research points to a notable correlation between an imbalance in gut microbiota and the development of type 2 diabetes mellitus (T2D) as well as its consequential ailment, coronary artery disease (CAD). The complexities underlying the association, especially in the context of diabetic coronary artery disease (DCAD), are not yet fully understood, and the causal links require further clarification. In this study, a bidirectional Mendelian randomization (MR) methodology was utilized to explore the causal relationships between gut microbiota, T2D, and CAD. By analyzing data from the DIAGRAM, GERA, UKB, FHS, and mibioGen cohorts and examining GWAS databases, we sought to uncover genetic variants linked to T2D, CAD, and variations in gut microbiota and metabolites, aiming to shed light on the potential mechanisms connecting gut microbiota with DCAD. Our investigation uncovered a marked causal link between the presence of Oxalobacter formigenes and an increased incidence of both T2D and CAD. Specifically, a ten-unit genetic predisposition towards T2D was found to be associated with a 6.1% higher probability of an increase in the Oxalobacteraceae family's presence (β = 0.061, 95% CI = 0.002-0.119). In a parallel finding, an augmented presence of Oxalobacter was related to an 8.2% heightened genetic likelihood of CAD (β = 0.082, 95% CI = 0.026-0.137). This evidence indicates a critical pathway by which T2D can potentially raise the risk of CAD via alterations in gut microbiota. Additionally, our analyses reveal a connection between CAD risk and Methanobacteria, thus providing fresh perspectives on the roles of TMAO and carnitine in the etiology of CAD. The data also suggest a direct causal relationship between increased levels of certain metabolites - proline, lysophosphatidylcholine, asparagine, and salicylurate - and the prevalence of both T2D and CAD. Sensitivity assessments reinforce the notion that changes in Oxalobacter formigenes could pose a risk for DCAD. There is also evidence to suggest that DCAD may, in turn, affect the gut microbiota's makeup. Notably, a surge in serum TMAO levels in individuals with CAD, coinciding with a reduced presence of methanogens, has been identified as a potentially significant factor for future examination.
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Affiliation(s)
- Zhaopei Zeng
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Junxiong Qiu
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yu Chen
- Department of Surgical Oncology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Diefei Liang
- Department of Endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Feng Wei
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Cardiothoracic Surgery, Shenshan Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Shanwei, China
| | - Yuan Fu
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jiarui Zhang
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiexiao Wei
- Department of Cardiology, Chinese PLA General Hospital, Beijing, China
| | - Xinyi Zhang
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jun Tao
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Liling Lin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Junmeng Zheng
- Department of Cardiovascular Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
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Ma L, Chang X, Gao J, Zhang Y, Chen Y, Zhou H, Zhou N, Du N, Li J, Bi J, Chen Z, Chen X, He Q. METTL3 boosts mitochondrial fission and induces cardiac fibrosis after ischemia/reperfusion injury. Int J Biol Sci 2024; 20:433-445. [PMID: 38169612 PMCID: PMC10758110 DOI: 10.7150/ijbs.87535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 10/30/2023] [Indexed: 01/05/2024] Open
Abstract
METTL3, an RNA methyltransferase enzyme, exerts therapeutic effects on various cardiovascular diseases. Myocardial ischemia-reperfusion injury (MIRI) and subsequently cardiac fibrosis is linked to acute cardiomyocyte death or dysfunction induced by mitochondrial damage, particularly mitochondrial fission. Our research aims to elucidate the potential mechanisms underlying the therapeutic actions of METTL3 in MIRI, with focus on mitochondrial fission. When compared with Mettl3flox mice subjected to MIRI, Mettl3 cardiomyocyte knockout (Mettl3Cko) mice have reduced infarct size, decreased serum levels of myocardial injury-related factors, limited cardiac fibrosis, and preserved myocardial ultrastructure and contractile/relaxation capacity. The cardioprotective actions of Mettl3 knockout were associated with reduced inflammatory responses, decreased myocardial neutrophil infiltration, and suppression of cardiomyocyte death. Through signaling pathway validation experiments and assays in cultured HL-1 cardiomyocytes exposed to hypoxia/reoxygenation, we confirmed that Mettl3 deficiency interfere with DNA-PKcs phosphorylation, thereby blocking the downstream activation of Fis1 and preventing pathological mitochondrial fission. In conclusion, this study confirms that inhibition of METTL3 can alleviate myocardial cardiac fibrosis inflammation and prevent cardiomyocyte death under reperfusion injury conditions by disrupting DNA-PKcs/Fis1-dependent mitochondrial fission, ultimately improving cardiac function. These findings suggest new approaches for clinical intervention in patients with MIRI.
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Affiliation(s)
- Li Ma
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Xing Chang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Jing Gao
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Ying Zhang
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing 100048, China
| | - Ye Chen
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing 100048, China
| | - Hao Zhou
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing 100048, China
| | - Na Zhou
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Na Du
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Jiamin Li
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Jiachen Bi
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Ziyue Chen
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Xinxin Chen
- Heart Center, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China
| | - Qingyong He
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
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5
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Zhang X, Zhou H, Chang X. Involvement of mitochondrial dynamics and mitophagy in diabetic endothelial dysfunction and cardiac microvascular injury. Arch Toxicol 2023; 97:3023-3035. [PMID: 37707623 DOI: 10.1007/s00204-023-03599-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 08/30/2023] [Indexed: 09/15/2023]
Abstract
Endothelial cells (ECs), found in the innermost layer of blood vessels, are crucial for maintaining the structure and function of coronary microcirculation. Dysregulated coronary microcirculation poses a fundamental challenge in diabetes-related myocardial microvascular injury, impacting myocardial blood perfusion, thrombogenesis, and inflammation. Extensive research aims to understand the mechanistic connection and functional relationship between cardiac EC dysfunction and the development, diagnosis, and treatment of diabetes-related myocardial microvascular injury. Despite the low mitochondrial content in ECs, mitochondria act as sensors of environmental and cellular stress, influencing EC viability, structure, and function. Mitochondrial dynamics and mitophagy play a vital role in orchestrating mitochondrial responses to various stressors by regulating morphology, localization, and degradation. Impaired mitochondrial dynamics or reduced mitophagy is associated with EC dysfunction, serving as a potential molecular basis and promising therapeutic target for diabetes-related myocardial microvascular injury. This review introduces newly recognized mechanisms of damaged coronary microvasculature in diabetes-related microvascular injury and provides updated insights into the molecular aspects of mitochondrial dynamics and mitophagy. Additionally, novel targeted therapeutic approaches against diabetes-related microvascular injury or endothelial dysfunction, focusing on mitochondrial fission and mitophagy in endothelial cells, are summarized.
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Affiliation(s)
- Xiao Zhang
- Dermatology, Liaocheng Hospital of Traditional Chinese Medicine, Liaocheng, 252000, China
| | - Hao Zhou
- Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing, 100048, China.
| | - Xing Chang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, 5 Beixiagge, Xicheng District, Beijing, 100053, China.
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6
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Li H, Chen D, Zhang X, Chen M, Zhi Y, Cui W, Li S, Xu F, Tan Y, Zhou H, Chang X, Chen H. Screening of an FDA-approved compound library identifies apigenin for the treatment of myocardial injury. Int J Biol Sci 2023; 19:5233-5244. [PMID: 37928261 PMCID: PMC10620826 DOI: 10.7150/ijbs.85204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/29/2023] [Indexed: 11/07/2023] Open
Abstract
Apigenin is the active ingredient in Ludangshen. Although previous studies reported the cardioprotective actions of apigenin against doxorubicin (Dox)-induced cardiomyopathy, the underlying mechanisms remain incompletely understood. Since apigenin beneficially regulates various aspects of mitochondrial function and dynamics, we asked whether apigenin improves heart function in mice with Dox-induced cardiomyopathy by regulating the mitochondrial unfolded protein response (UPRmt). Co-administration of apigenin significantly restored heart function, reduced myocardial swelling, inhibited cardiac inflammation, increased cardiac transcription of UPRmt-related genes, and promoted cardiomyocyte survival in Dox-treated mice. In turn, blockade of UPRmt abolished the mito- and cytoprotective effects of apigenin, evidenced by decreased ATP production, suppressed mitochondrial antioxidant capacity, and increased apoptosis, in Dox-treated, cultured HL-1 cardiomyocytes. Furthermore, apigenin treatment prevented Dox-induced downregulation of Sirt1 and Atf5 expression, and the beneficial effects of apigenin were completely nullified in Sirt1 knockout (KO) mice or after siRNA-mediated Sirt1 knockdown in vitro. We thus provide novel evidence for a promotive effect of apigenin on UPRmt via regulation of the Sirt1/Atf5 pathway. Our findings uncover that apigenin seems to be an effective therapeutic agent to alleviate Dox-mediated cardiotoxicity.
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Affiliation(s)
- Haixia Li
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Dong Chen
- Dongzhimen Hospital of Beijing University of Traditional Chinese Medicine, Beijing, 100000, China
| | - Xiaoqin Zhang
- Beijing University of Chinese Medicine, Beijing, 100029, China
| | | | - Yinghao Zhi
- Wenzhou TCM Hospital of Zhejiang Chinese Medical University, Wenzhou, 325000, China
| | - Weilu Cui
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Shanshan Li
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Fan Xu
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Ying Tan
- School of Medicine, Southern University of Science and Technology (SUSTech), Shenzhen, Guangdong, China
| | - Hao Zhou
- School of Medicine, Southern University of Science and Technology (SUSTech), Shenzhen, Guangdong, China
| | - Xing Chang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Hengwen Chen
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
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7
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Cai C, Li Z, Zheng Z, Guo Z, Li Q, Deng S, Shi N, Ou Q, Zhou H, Guo Z, Chen Z, Zhu H. Pgam5-mediated PHB2 dephosphorylation contributes to endotoxemia-induced myocardial dysfunction by inhibiting mitophagy and the mitochondrial unfolded protein response. Int J Biol Sci 2023; 19:4657-4671. [PMID: 37781037 PMCID: PMC10535708 DOI: 10.7150/ijbs.85767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 08/11/2023] [Indexed: 10/03/2023] Open
Abstract
Numerous mitochondrial abnormalities are reported to result from excessive inflammation during endotoxemia. Prohibitin 2 (PHB2) and phosphoglycerate mutase 5 (Pgam5) have been associated with altered mitochondrial homeostasis in several cardiovascular diseases; however, their role in endotoxemia-related myocardial dysfunction has not been explored. Our experiments were aimed to evaluate the potential contribution of Pgam5 and PHB2 to endotoxemia-induced mitochondrial dysfunction in cardiomyocytes, with a focus on two endogenous protective programs that sustain mitochondrial integrity, namely mitophagy and the mitochondrial unfolded protein response (UPRmt). We found that PHB2 transgenic mice are resistant to endotoxemia-mediated myocardial depression and mitochondrial damage. Our assays indicated that PHB2 overexpression activates mitophagy and the UPRmt, which maintains mitochondrial metabolism, prevents oxidative stress injury, and enhances cardiomyocyte viability. Molecular analyses further showed that Pgam5 binds to and dephosphorylates PHB2, resulting in cytosolic translocation of mitochondrial PHB2. Silencing of Pgam5 or transfection of a phosphorylated PHB2 mutant in mouse HL-1 cardiomyocytes prevented the loss of mitochondrially-localized PHB2 and activated mitophagy and UPRmt in the presence of LPS. Notably, cardiomyocyte-specific deletion of Pgam5 in vivo attenuated LPS-mediated myocardial dysfunction and preserved cardiomyocyte viability. These findings suggest that Pgam5/PHB2 signaling and mitophagy/UPRmt are potential targets for the treatment of endotoxemia-related cardiac dysfunction.
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Affiliation(s)
- Chen Cai
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Ziying Li
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Zemao Zheng
- Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Zhongzhou Guo
- Department of Pharmacy, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Qian Li
- The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Shuxian Deng
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Nengxian Shi
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Qing Ou
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Hao Zhou
- School of Medicine, University of Rochester Medical Center Rochester, Rochester, NY 14642, United States
| | - Zhigang Guo
- Department of Cardiology, Huiqiao Medical Center, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Zhongqing Chen
- Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- Department of Critical Care Medicine, The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China
| | - Hang Zhu
- Senior Department of Cardiology, The Sixth Medical Center of People's Liberation Army General Hospital, Beijing, China
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