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Pasupuleti SK, Ramdas B, Burns SS, Palam LR, Kanumuri R, Kumar R, Pandhiri TR, Dave UP, Yellapu NK, Zhou X, Zhang C, Sandusky GE, Yu Z, Honigberg MC, Bick AG, Griffin GK, Niroula A, Ebert BL, Paczesny S, Natarajan P, Kapur R. Obesity-induced inflammation exacerbates clonal hematopoiesis. J Clin Invest 2023; 133:e163968. [PMID: 37071471 PMCID: PMC10231999 DOI: 10.1172/jci163968] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 04/07/2023] [Indexed: 04/19/2023] Open
Abstract
Characterized by the accumulation of somatic mutations in blood cell lineages, clonal hematopoiesis of indeterminate potential (CHIP) is frequent in aging and involves the expansion of mutated hematopoietic stem and progenitor cells (HSC/Ps) that leads to an increased risk of hematologic malignancy. However, the risk factors that contribute to CHIP-associated clonal hematopoiesis (CH) are poorly understood. Obesity induces a proinflammatory state and fatty bone marrow (FBM), which may influence CHIP-associated pathologies. We analyzed exome sequencing and clinical data for 47,466 individuals with validated CHIP in the UK Biobank. CHIP was present in 5.8% of the study population and was associated with a significant increase in the waist-to-hip ratio (WHR). Mouse models of obesity and CHIP driven by heterozygosity of Tet2, Dnmt3a, Asxl1, and Jak2 resulted in exacerbated expansion of mutant HSC/Ps due in part to excessive inflammation. Our results show that obesity is highly associated with CHIP and that a proinflammatory state could potentiate the progression of CHIP to more significant hematologic neoplasia. The calcium channel blockers nifedipine and SKF-96365, either alone or in combination with metformin, MCC950, or anakinra (IL-1 receptor antagonist), suppressed the growth of mutant CHIP cells and partially restored normal hematopoiesis. Targeting CHIP-mutant cells with these drugs could be a potential therapeutic approach to treat CH and its associated abnormalities in individuals with obesity.
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Affiliation(s)
| | - Baskar Ramdas
- Herman B Wells Center for Pediatric Research, Department of Pediatrics and
| | - Sarah S. Burns
- Herman B Wells Center for Pediatric Research, Department of Pediatrics and
| | | | - Rahul Kanumuri
- Herman B Wells Center for Pediatric Research, Department of Pediatrics and
| | - Ramesh Kumar
- Herman B Wells Center for Pediatric Research, Department of Pediatrics and
| | | | - Utpal P. Dave
- Division of Hematology/Oncology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Nanda Kumar Yellapu
- Department of Biostatistics and Data Science, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Xinyu Zhou
- Department of Medical and Molecular Genetics and
| | - Chi Zhang
- Department of Medical and Molecular Genetics and
| | - George E. Sandusky
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Zhi Yu
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, Massachusetts, USA
- Program in Medical and Population Genetics and the Cardiovascular Disease Initiative, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA
| | - Michael C. Honigberg
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Alexander G. Bick
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Gabriel K. Griffin
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Epigenomics Program, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA
| | - Abhishek Niroula
- Program in Medical and Population Genetics and the Cardiovascular Disease Initiative, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA
| | - Benjamin L. Ebert
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sophie Paczesny
- Department of Microbiology and Immunology, Medical University of South Carolina, Charlestown, South Carolina, USA
| | - Pradeep Natarajan
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, Massachusetts, USA
- Program in Medical and Population Genetics and the Cardiovascular Disease Initiative, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Reuben Kapur
- Herman B Wells Center for Pediatric Research, Department of Pediatrics and
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Liu TT, Qiu CY, Hu WP. Metformin inhibits spontaneous excitatory postsynaptic currents in spinal dorsal cord neurons from paclitaxel-treated rats. Front Synaptic Neurosci 2023; 15:1191383. [PMID: 37216004 PMCID: PMC10195993 DOI: 10.3389/fnsyn.2023.1191383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 04/20/2023] [Indexed: 05/24/2023] Open
Abstract
Introduction Cancer patients treated with paclitaxel often develop chemotherapy-induced peripheral neuropathy, which has not been effectively treated with drugs. The anti-diabetic drug metformin is effective in the treatment of neuropathic pain. The aim of this study was to elucidate effect of metformin on paclitaxel-induced neuropathic pain and spinal synaptic transmission. Methods Electrophysiological experiments on rat spinal slices were performed in vitro and mechanical allodynia quantified in vitro. Results The present data demonstrated that intraperitoneal injection of paclitaxel produced mechanical allodynia and potentiated spinal synaptic transmission. Intrathecal injection of metformin significantly reversed the established mechanical allodynia induced by paclitaxel in rats. Either spinal or systemic administration of metformin significantly inhibited the increased frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in spinal dorsal horn neurons from paclitaxel-treated rats. We found that 1 h incubation of metformin also reduced the frequency rather than the amplitude of sEPSCs in the spinal slices from paclitaxel-treated rats. Discussion These results suggested that metformin was able to depress the potentiated spinal synaptic transmission, which may contribute to alleviating the paclitaxel-induced neuropathic pain.
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Affiliation(s)
- Ting-Ting Liu
- School of Basic Medical Sciences, Xianning Medical College, Hubei University of Science and Technology, Xianning, Hubei, China
| | - Chun-Yu Qiu
- School of Basic Medical Sciences, Xianning Medical College, Hubei University of Science and Technology, Xianning, Hubei, China
| | - Wang-Ping Hu
- School of Basic Medical Sciences, Xianning Medical College, Hubei University of Science and Technology, Xianning, Hubei, China
- Department of Physiology, Hubei College of Chinese Medicine, Jingzhou, Hubei, China
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Sadeh TT, Baines RA, Black GC, Manson F. Ca v1.4 congenital stationary night blindness is associated with an increased rate of proteasomal degradation. Front Cell Dev Biol 2023; 11:1161548. [PMID: 37206923 PMCID: PMC10188973 DOI: 10.3389/fcell.2023.1161548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/17/2023] [Indexed: 05/21/2023] Open
Abstract
Pathogenic, generally loss-of-function, variants in CACNA1F, encoding the Cav1.4α1 calcium channel, underlie congenital stationary night blindness type 2 (CSNB2), a rare inherited retinal disorder associated with visual disability. To establish the underlying pathomechanism, we investigated 10 clinically derived CACNA1F missense variants located across pore-forming domains, connecting loops, and the carboxy-tail domain of the Cav1.4α subunit. Homology modeling showed that all variants cause steric clashes; informatics analysis correctly predicted pathogenicity for 7/10 variants. In vitro analyses demonstrated that all variants cause a decrease in current, global expression, and protein stability and act through a loss-of-function mechanism and suggested that the mutant Cav1.4α proteins were degraded by the proteasome. We showed that the reduced current for these variants could be significantly increased through treatment with clinical proteasome inhibitors. In addition to facilitating clinical interpretation, these studies suggest that proteasomal inhibition represents an avenue of potential therapeutic intervention for CSNB2.
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Affiliation(s)
- Tal T. Sadeh
- Division of Evolution, Infection and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Richard A. Baines
- Division of Neuroscience, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Graeme C. Black
- Division of Evolution, Infection and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Genomic Medicine, Manchester Academic Health Sciences Centre, Manchester University NHS Foundation Trust, St Mary’s Hospital, Manchester, United Kingdom
- *Correspondence: Graeme C. Black,
| | - Forbes Manson
- Division of Evolution, Infection and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
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Lee TTL, Hui JMH, Lee YHA, Satti DI, Shum YKL, Kiu PTH, Wai AKC, Liu T, Wong WT, Chan JSK, Cheung BMY, Wong ICK, Cheng SH, Tse G. Sulfonylurea Is Associated With Higher Risks of Ventricular Arrhythmia or Sudden Cardiac Death Compared With Metformin: A Population‐Based Cohort Study. J Am Heart Assoc 2022; 11:e026289. [PMID: 36102222 DOI: 10.1161/jaha.122.026289] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Background
Commonly prescribed diabetic medications such as metformin and sulfonylurea may be associated with different arrhythmogenic risks. This study compared the risk of ventricular arrhythmia or sudden cardiac death between metformin and sulfonylurea users in patients with type 2 diabetes.
Methods and Results
Patients aged ≥40 years who were diagnosed with type 2 diabetes or prescribed antidiabetic agents in Hong Kong between January 1, 2009, and December 31, 2009, were included and followed up until December 31, 2019. Patients prescribed with both metformin and sulfonylurea or had prior myocardial infarction were excluded. The study outcome was a composite of ventricular arrhythmia or sudden cardiac death. Metformin users and sulfonylurea users were matched at a 1:1 ratio by propensity score matching. The matched cohort consisted of 16 596 metformin users (47.70% men; age, 68±11 years; mean follow‐up, 4.92±2.55 years) and 16 596 sulfonylurea users (49.80% men; age, 70±11 years; mean follow‐up, 4.93±2.55 years). Sulfonylurea was associated with higher risk of ventricular arrhythmia or sudden cardiac death than metformin hazard ratio (HR, 1.90 [95% CI, 1.73–2.08]). Such difference was consistently observed in subgroup analyses stratifying for insulin usage or known coronary heart disease.
Conclusions
Sulfonylurea use is associated with higher risk of ventricular arrhythmia or sudden cardiac death than metformin in patients with type 2 diabetes.
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Affiliation(s)
- Teddy Tai Loy Lee
- Department of Emergency Medicine School of Clinical Medicine, The University of Hong Kong Hong Kong China
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Jeremy Man Ho Hui
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Yan Hiu Athena Lee
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Danish Iltaf Satti
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Yuki Ka Ling Shum
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Pias Tang Hoi Kiu
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Abraham Ka Chung Wai
- Department of Emergency Medicine School of Clinical Medicine, The University of Hong Kong Hong Kong China
| | - Tong Liu
- Tianjin Institute of Cardiology, The Second Hospital of Tianjin Medical University Tianjin China
| | - Wing Tak Wong
- School of Life Sciences, State Key Laboratory of Agrobiotechnology (CUHK), The Chinese University of Hong Kong Hong Kong China
| | - Jeffrey Shi Kai Chan
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
| | - Bernard Man Yung Cheung
- Division of Clinical Pharmacology School of Clinical Medicine, The University of Hong Kong Hong Kong China
| | - Ian Chi Kei Wong
- Department of Pharmacology and Pharmacy University of Hong Kong Hong Kong China
- UCL School of Pharmacy Medicines Optimisation Research and Education (CMORE) London United Kingdom
| | - Shuk Han Cheng
- Department of Infectious Diseases and Public Health City University of Hong Kong Hong Kong China
| | - Gary Tse
- Diabetes Research Unit, Cardiovascular Analytics Group China‐UK Collaboration Hong Kong China
- Tianjin Institute of Cardiology, The Second Hospital of Tianjin Medical University Tianjin China
- Kent and Medway Medical School Canterbury United Kingdom
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Gonçalves CA, Sesterheim P, Wartchow KM, Bobermin LD, Leipnitz G, Quincozes-Santos A. Why antidiabetic drugs are potentially neuroprotective during the Sars-CoV-2 pandemic: The focus on astroglial UPR and calcium-binding proteins. Front Cell Neurosci 2022; 16:905218. [PMID: 35966209 PMCID: PMC9374064 DOI: 10.3389/fncel.2022.905218] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/30/2022] [Indexed: 11/30/2022] Open
Abstract
We are living in a terrifying pandemic caused by Sars-CoV-2, in which patients with diabetes mellitus have, from the beginning, been identified as having a high risk of hospitalization and mortality. This viral disease is not limited to the respiratory system, but also affects, among other organs, the central nervous system. Furthermore, we already know that individuals with diabetes mellitus exhibit signs of astrocyte dysfunction and are more likely to develop cognitive deficits and even dementia. It is now being realized that COVID-19 incurs long-term effects and that those infected can develop several neurological and psychiatric manifestations. As this virus seriously compromises cell metabolism by triggering several mechanisms leading to the unfolded protein response (UPR), which involves endoplasmic reticulum Ca2+ depletion, we review here the basis involved in this response that are intimately associated with the development of neurodegenerative diseases. The discussion aims to highlight two aspects—the role of calcium-binding proteins and the role of astrocytes, glial cells that integrate energy metabolism with neurotransmission and with neuroinflammation. Among the proteins discussed are calpain, calcineurin, and sorcin. These proteins are emphasized as markers of the UPR and are potential therapeutic targets. Finally, we discuss the role of drugs widely prescribed to patients with diabetes mellitus, such as statins, metformin, and calcium channel blockers. The review assesses potential neuroprotection mechanisms, focusing on the UPR and the restoration of reticular Ca2+ homeostasis, based on both clinical and experimental data.
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Affiliation(s)
- Carlos-Alberto Gonçalves
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- *Correspondence: Carlos-Alberto Gonçalves
| | - Patrícia Sesterheim
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Krista M. Wartchow
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Larissa Daniele Bobermin
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Guilhian Leipnitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - André Quincozes-Santos
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Metformin Reduces Potassium Currents and Prolongs Repolarization in Non-Diabetic Heart. Int J Mol Sci 2022; 23:ijms23116021. [PMID: 35682699 PMCID: PMC9181026 DOI: 10.3390/ijms23116021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/14/2022] [Accepted: 05/24/2022] [Indexed: 01/27/2023] Open
Abstract
Metformin is the first choice drug for the treatment of type 2 diabetes due to positive results in reducing hyperglycaemia and insulin resistance. However, diabetic patients have higher risk of ventricular arrhythmia and sudden cardiac death, and metformin failed to reduce ventricular arrhythmia in clinical trials. In order to explore the mechanisms responsible for the lack of protective effect, we investigated in vivo the effect of metformin on cardiac electrical activity in non-diabetic rats; and in vitro in isolated ventricular myocytes, HEK293 cells expressing the hERG channel and human induced pluripotent stem cells derived cardiomyocytes (hIPS-CMs). Surface electrocardiograms showed that long-term metformin treatment (7 weeks) at therapeutic doses prolonged cardiac repolarization, reflected as QT and QTc interval duration, and increased ventricular arrhythmia during the caffeine/dobutamine challenge. Patch-clamp recordings in ventricular myocytes isolated from treated animals showed that the cellular mechanism is a reduction in the cardiac transient outward potassium current (Ito). In vitro, incubation with metformin for 24 h also reduced Ito, prolonged action potential duration, and increased spontaneous contractions in ventricular myocytes isolated from control rats. Metformin incubation also reduced IhERG in HEK293 cells. Finally, metformin incubation prolonged action potential duration at 30% and 90% of repolarization in hIPS-CMs, which is compatible with the reduction of Ito and IhERG. Our results show that metformin directly modifies the electrical behavior of the normal heart. The mechanism consists in the inhibition of repolarizing currents and the subsequent decrease in repolarization capacity, which prolongs AP and QTc duration.
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Grover A, Sharma K, Gautam S, Gautam S, Gulati M, Singh SK. Diabetes and Its Complications: Therapies Available, Anticipated and Aspired. Curr Diabetes Rev 2021; 17:397-420. [PMID: 33143627 DOI: 10.2174/1573399816666201103144231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/26/2020] [Accepted: 09/12/2020] [Indexed: 11/22/2022]
Abstract
Worldwide, diabetes ranks among the ten leading causes of mortality. Prevalence of diabetes is growing rapidly in low and middle income countries. It is a progressive disease leading to serious co-morbidities, which results in increased cost of treatment and over-all health system of the country. Pathophysiological alterations in Type 2 Diabetes (T2D) progressed from a simple disturbance in the functioning of the pancreas to triumvirate to ominous octet to egregious eleven to dirty dozen model. Due to complex interplay of multiple hormones in T2D, there may be multifaceted approach in its management. The 'long-term secondary complications' in uncontrolled diabetes may affect almost every organ of the body, and finally may lead to multi-organ dysfunction. Available therapies are inconsistent in maintaining long term glycemic control and their long term use may be associated with adverse effects. There is need for newer drugs, not only for glycemic control but also for prevention or mitigation of secondary microvascular and macrovascular complications. Increased knowledge of the pathophysiology of diabetes has contributed to the development of novel treatments. Several new agents like Glucagon Like Peptide - 1 (GLP-1) agonists, Dipeptidyl Peptidase IV (DPP-4) inhibitors, amylin analogues, Sodium-Glucose transport -2 (SGLT- 2) inhibitors and dual Peroxisome Proliferator-Activated Receptor (PPAR) agonists are available or will be available soon, thus extending the range of therapy for T2D, thereby preventing its long term complications. The article discusses the pathophysiology of diabetes along with its comorbidities, with a focus on existing and novel upcoming antidiabetic drugs which are under investigation. It also dives deep to deliberate upon the novel therapies that are in various stages of development. Adding new options with new mechanisms of action to the treatment armamentarium of diabetes may eventually help improve outcomes and reduce its economic burden.
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Affiliation(s)
- Anu Grover
- Ipca Laboratories, Mumbai - 400063, India
| | - Komal Sharma
- Bhupal Nobles' Institute of Pharmaceutical Sciences, Udaipur, India
| | - Suresh Gautam
- Department of Biochemistry, Pacific Institute of Medical Sciences, Udaipur, India
| | - Srishti Gautam
- Ravinder Nath Tagore Medical College and Maharana Bhupal Govt. Hospital, Udaipur, India
| | - Monica Gulati
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab- 144411, India
| | - Sachin Kumar Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab- 144411, India
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Nantsupawat T, Wongcharoen W, Chattipakorn SC, Chattipakorn N. Effects of metformin on atrial and ventricular arrhythmias: evidence from cell to patient. Cardiovasc Diabetol 2020; 19:198. [PMID: 33234131 PMCID: PMC7687769 DOI: 10.1186/s12933-020-01176-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/15/2020] [Indexed: 12/23/2022] Open
Abstract
Metformin has been shown to have various cardiovascular benefits beyond its antihyperglycemic effects, including a reduction in stroke, heart failure, myocardial infarction, cardiovascular death, and all-cause mortality. However, the roles of metformin in cardiac arrhythmias are still unclear. It has been shown that metformin was associated with decreased incidence of atrial fibrillation in diabetic patients with and without myocardial infarction. This could be due to the effects of metformin on preventing the structural and electrical remodeling of left atrium via attenuating intracellular reactive oxygen species, activating 5′ adenosine monophosphate-activated protein kinase, improving calcium homeostasis, attenuating inflammation, increasing connexin-43 gap junction expression, and restoring small conductance calcium-activated potassium channels current. For ventricular arrhythmias, in vivo reports demonstrated that activation of 5′ adenosine monophosphate-activated protein kinase and phosphorylated connexin-43 by metformin played a key role in ischemic ventricular arrhythmias reduction. However, metformin failed to show anti-ventricular arrhythmia benefits in clinical trials. In this review, in vitro and in vivo reports regarding the effects of metformin on both atrial arrhythmias and ventricular arrhythmias are comprehensively summarized and presented. Consistent and controversial findings from clinical trials are also summarized and discussed. Due to limited numbers of reports, further studies are needed to elucidate the mechanisms and effects of metformin on cardiac arrhythmias. Furthermore, randomized controlled trials are needed to clarify effects of metformin on cardiac arrhythmias in human.
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Affiliation(s)
- Teerapat Nantsupawat
- Division of Cardiology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Chiang Mai, 50200, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Wanwarang Wongcharoen
- Division of Cardiology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Chiang Mai, 50200, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Siriporn C Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Chiang Mai, 50200, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Nipon Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Chiang Mai, 50200, Thailand. .,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand. .,Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
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