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Fitts RH, Wang X, Kwok WM, Camara AKS. Cardiomyocyte Adaptation to Exercise: K+ Channels, Contractility and Ischemic Injury. Int J Sports Med 2024. [PMID: 38648799 DOI: 10.1055/a-2296-7604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Cardiovascular disease is a leading cause of morbidity and mortality, and exercise-training (TRN) is known to reduce risk factors and protect the heart from ischemia and reperfusion injury. Though the cardioprotective effects of exercise are well-documented, underlying mechanisms are not well understood. This review highlights recent findings and focuses on cardiac factors with emphasis on K+ channel control of the action potential duration (APD), β-adrenergic and adenosine regulation of cardiomyocyte function, and mitochondrial Ca2+ regulation. TRN-induced prolongation and shortening of the APD at low and high activation rates, respectively, is discussed in the context of a reduced response of the sarcolemma delayed rectifier potassium channel (IK) and increased content and activation of the sarcolemma KATP channel. A proposed mechanism underlying the latter is presented, including the phosphatidylinositol-3kinase/protein kinase B pathway. TRN induced increases in cardiomyocyte contractility and the response to adrenergic agonists are discussed. The TRN-induced protection from reperfusion injury is highlighted by the increased content and activation of the sarcolemma KATP channel and the increased phosphorylated glycogen synthase kinase-3β, which aid in preventing mitochondrial Ca2+ overload and mitochondria-triggered apoptosis. Finally, a brief section is presented on the increased incidences of atrial fibrillation associated with age and in life-long exercisers.
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Affiliation(s)
- Robert H Fitts
- Biological Sciences, Marquette University, Milwaukee, United States
| | - Xinrui Wang
- Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, United States
| | - Wai-Meng Kwok
- Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, United States
- Anesthesiology, Medical College of Wisconsin, Milwaukee, United States
- Cancer Center, Medical College of Wisconsin, Milwaukee, United States
| | - Amadou K S Camara
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, United States
- Anesthesiology, Medical College of Wisconsin, Milwaukee, United States
- Cancer Center, Medical College of Wisconsin, Milwaukee, United States
- Physiology, Medical College of Wisconsin, Milwaukee, United States
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2
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Boengler K, Eickelmann C, Kleinbongard P. Mitochondrial Kinase Signaling for Cardioprotection. Int J Mol Sci 2024; 25:4491. [PMID: 38674076 PMCID: PMC11049936 DOI: 10.3390/ijms25084491] [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: 03/01/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Myocardial ischemia/reperfusion injury is reduced by cardioprotective adaptations such as local or remote ischemic conditioning. The cardioprotective stimuli activate signaling cascades, which converge on mitochondria and maintain the function of the organelles, which is critical for cell survival. The signaling cascades include not only extracellular molecules that activate sarcolemmal receptor-dependent or -independent protein kinases that signal at the plasma membrane or in the cytosol, but also involve kinases, which are located to or within mitochondria, phosphorylate mitochondrial target proteins, and thereby modify, e.g., respiration, the generation of reactive oxygen species, calcium handling, mitochondrial dynamics, mitophagy, or apoptosis. In the present review, we give a personal and opinionated overview of selected protein kinases, localized to/within myocardial mitochondria, and summarize the available data on their role in myocardial ischemia/reperfusion injury and protection from it. We highlight the regulation of mitochondrial function by these mitochondrial protein kinases.
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Affiliation(s)
- Kerstin Boengler
- Institute of Physiology, Justus-Liebig University, 35392 Giessen, Germany
| | - Chantal Eickelmann
- Institute for Pathophysiology, West German Heart and Vascular Center, University of Essen Medical School, 45147 Essen, Germany; (C.E.); (P.K.)
| | - Petra Kleinbongard
- Institute for Pathophysiology, West German Heart and Vascular Center, University of Essen Medical School, 45147 Essen, Germany; (C.E.); (P.K.)
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3
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Flores K, Siques P, Brito J, Arribas SM. AMPK and the Challenge of Treating Hypoxic Pulmonary Hypertension. Int J Mol Sci 2022; 23:ijms23116205. [PMID: 35682884 PMCID: PMC9181235 DOI: 10.3390/ijms23116205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/29/2022] [Accepted: 04/30/2022] [Indexed: 02/01/2023] Open
Abstract
Hypoxic pulmonary hypertension (HPH) is characterized by sustained elevation of pulmonary artery pressure produced by vasoconstriction and hyperproliferative remodeling of the pulmonary artery and subsequent right ventricular hypertrophy (RVH). The search for therapeutic targets for cardiovascular pathophysiology has extended in many directions. However, studies focused on mitigating high-altitude pulmonary hypertension (HAPH) have been rare. Because AMP-activated protein kinase (AMPK) is involved in cardiovascular and metabolic pathology, AMPK is often studied as a potential therapeutic target. AMPK is best characterized as a sensor of cellular energy that can also restore cellular metabolic homeostasis. However, AMPK has been implicated in other pathways with vasculoprotective effects. Notably, cellular metabolic stress increases the intracellular ADP/ATP or AMP/ATP ratio, and AMPK activation restores ATP levels by activating energy-producing catabolic pathways and inhibiting energy-consuming anabolic pathways, such as cell growth and proliferation pathways, promoting cardiovascular protection. Thus, AMPK activation plays an important role in antiproliferative, antihypertrophic and antioxidant pathways in the pulmonary artery in HPH. However, AMPK plays contradictory roles in promoting HPH development. This review describes the main findings related to AMPK participation in HPH and its potential as a therapeutic target. It also extrapolates known AMPK functions to discuss the less-studied HAPH context.
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Affiliation(s)
- Karen Flores
- Institute of Health Studies, University Arturo Prat, Av. Arturo Prat 2120, Iquique 1110939, Chile; (P.S.); (J.B.)
- Institute DECIPHER, German-Chilean Institute for Research on Pulmonary Hypoxia and Its Health Sequelae, 20251 Hamburg, Germany and Iquique 1100000, Chile
- Correspondence: ; Tel.: +56-572526392
| | - Patricia Siques
- Institute of Health Studies, University Arturo Prat, Av. Arturo Prat 2120, Iquique 1110939, Chile; (P.S.); (J.B.)
- Institute DECIPHER, German-Chilean Institute for Research on Pulmonary Hypoxia and Its Health Sequelae, 20251 Hamburg, Germany and Iquique 1100000, Chile
| | - Julio Brito
- Institute of Health Studies, University Arturo Prat, Av. Arturo Prat 2120, Iquique 1110939, Chile; (P.S.); (J.B.)
- Institute DECIPHER, German-Chilean Institute for Research on Pulmonary Hypoxia and Its Health Sequelae, 20251 Hamburg, Germany and Iquique 1100000, Chile
| | - Silvia M. Arribas
- Department of Physiology, University Autonoma of Madrid, 28049 Madrid, Spain;
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Naryzhnaya NV, Maslov LN, Derkachev IA, Fu F. The Significance of NO-Synthase, Reactive Oxygen Species, Kinases and KATP-Channels in the Development of the Infarct-Limiting Effect of Adaptation to Hypoxia. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022020211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Naryzhnaya NV, Maslov LN, Derkachev IA, Ma H, Zhang Y, Prasad NR, Singh N, Fu F, Pei JM, Sarybaev A, Sydykov A. The effect of adaptation to hypoxia on cardiac tolerance to ischemia/reperfusion. J Biomed Res 2022:1-25. [PMID: 37183617 PMCID: PMC10387748 DOI: 10.7555/jbr.36.20220125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The acute myocardial infarction (AMI) and sudden cardiac death (SCD), both associated with acute cardiac ischemia, are one of the leading causes of adult death in economically developed countries. The development of new approaches for the treatment and prevention of AMI and SCD remains the highest priority for medicine. A study on the cardiovascular effects of chronic hypoxia (CH) may contribute to the development of these methods. Chronic hypoxia exerts both positive and adverse effects. The positive effects are the infarct-reducing, vasoprotective, and antiarrhythmic effects, which can lead to the improvement of cardiac contractility in reperfusion. The adverse effects are pulmonary hypertension and right ventricular hypertrophy. This review presents a comprehensive overview of how CH enhances cardiac tolerance to ischemia/reperfusion. It is an in-depth analysis of the published data on the underlying mechanisms, which can lead to future development of the cardioprotective effect of CH. A better understanding of the CH-activated protective signaling pathways may contribute to new therapeutic approaches in an increase of cardiac tolerance to ischemia/reperfusion.
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Tibenska V, Marvanova A, Elsnicova B, Hejnova L, Vebr P, Novotný J, Kolar F, Novakova O, M Zurmanova J. The cardioprotective effect persisting during recovery from cold acclimation is mediated by the β 2-adrenoceptor pathway and Akt activation. J Appl Physiol (1985) 2021; 130:746-755. [PMID: 33332989 DOI: 10.1152/japplphysiol.00756.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The infarct size-limiting effect elicited by cold acclimation (CA) is accompanied by increased mitochondrial resistance and unaltered β1-adrenergic receptor (AR) signaling persisting for 2 wk at room temperature. As the mechanism of CA-elicited cardioprotection is not fully understood, we examined the role of the salvage β2-AR/Gi/Akt pathway. Male Wistar rats were exposed to CA (8°C, 5 wk), whereas the recovery group (CAR) was kept at 24°C for additional 2 wk. We show that the total number of myocardial β-ARs in the left ventricular myocardium did not change after CA but decreased after CAR. We confirmed the infarct size-limiting effect in both CA and CAR groups. Acute administration of β2-AR inhibitor ICI-118551 abolished the protective effect in the CAR group but had no effect in the control and CA groups. The inhibitory Giα1/2 and Giα3 proteins increased in the membrane fraction of the CAR group, and the phospho-Akt (Ser473)-to-Akt ratio also increased. Expression, phosphorylation, and mitochondrial location of the Akt target glycogen synthase kinase (GSK-3β) were affected neither by CA nor by CAR. However, GSK-3β translocated from the Z-disk to the H-zone after CA, and acquired its original location after CAR. Our data indicate that the cardioprotection observed after CAR is mediated by the β2-AR/Gi pathway and Akt activation. Further studies are needed to unravel downstream targets of the central regulators of the CA process and the downstream targets of the Akt protein after CAR.NEW & NOTEWORTHY Cardioprotective effect of cold acclimation and that persisting for 2 wk after recovery engage in different mechanisms. The β2-adrenoceptor/Gi pathway and Akt are involved only in the mechanism of infarct size-limiting effect occurring during the recovery phase. GSK-3β translocated from the Z-line to the H-zone of sarcomeres by cold acclimation returns back to the original position after the recovery phase. The results provide new insights potentially useful for the development of cardiac therapies.
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Affiliation(s)
- Veronika Tibenska
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Aneta Marvanova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Barbara Elsnicova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Lucie Hejnova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Pavel Vebr
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiri Novotný
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Frantisek Kolar
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Olga Novakova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic.,Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jitka M Zurmanova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
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7
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Tong QH, Hu HY, Chai H, Wu AB, Guo XH, Wang S, Zhang YF, Fan XY. Dysregulation of the miR-1275/HK2 Axis Contributes to the Progression of Hypoxia/Reoxygenation-Induced Myocardial Injury. Arch Med Res 2021; 52:461-470. [PMID: 33551225 DOI: 10.1016/j.arcmed.2021.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 08/06/2020] [Accepted: 01/21/2021] [Indexed: 12/14/2022]
Abstract
OBJECTIVE This research was designed to investigate the function of miR-1275 in hypoxia/reoxygenation (H/R)-induced myocardial injury and its in-depth mechanism. METHODS Firstly, the differential expression of miR-1275 in patients with heart failure and healthy control were analyzed based on Gene Expression Omnibus (GEO) database. Then H/R model was constructed in vitro with AC16 cells. The qRT-PCR assay was performed to analyze the expression of miR-1275 in H/R-treated cells. Afterwards, CCK-8 assay and flow cytometry assay were carried out to detect the cells viability and apoptosis. Bioinformatics prediction, western blotting and dual-luciferase reporter assays were set to check the target gene of miR-1275. Finally, we used an Elisa to test the effect of miR-1275/HK2 axis on inflammatory factors. RESULTS We found that miR-1275 was highly expressed in patients with heart failure and H/R treated AC16 cells than that in control group, and inhibition of miR-1275 can alleviate induced-decrease of cell viability. Subsequently, we revealed that HK2 was a downstream target gene of miR-1275, which was lowly expressed in patients with heart failure. Furthermore, our data also suggested that inhibition of miR-1275 can significantly alleviate H/R-induced myocardial injury, which can also markedly decrease the concentration of pro-inflammatory factors TNF-α, IL-1 β and increase the concentration of anti-inflammatory factors IL-10 in H/R-treated AC16 cells, while knockdown of HK2 canceled the effect caused by miR-1275 deletion. CONCLUSIONS In summing, our results illustrated that miR-1275/HK2 axis act as a potential regulator to against H/R-induced AC16 cells injury through anti-inflammatory effect.
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Affiliation(s)
- Qin-Hong Tong
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Hai-Ying Hu
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Hui Chai
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Ai-Bin Wu
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Xiao-Hu Guo
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Shan Wang
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Yu-Feng Zhang
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China
| | - Xiao-Yong Fan
- Department of Cardiology, The First Peoples Hospital of Lanzhou, Lanzhou, P.R. China.
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8
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Naryzhnaya NV, Ma HJ, Maslov LN. The involvement of protein kinases in the cardioprotective effect of chronic hypoxia. Physiol Res 2020; 69:933-945. [PMID: 33129243 DOI: 10.33549/physiolres.934439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The purpose of this review is to analyze the involvement of protein kinases in the cardioprotective mechanism induced by chronic hypoxia. It has been reported that chronic intermittent hypoxia contributes to increased expression of the following kinases in the myocardium: PKCdelta, PKCalpha, p-PKCepsilon, p-PKCalpha, AMPK, p-AMPK, CaMKII, p-ERK1/2, p-Akt, PI3-kinase, p-p38, HK-1, and HK-2; whereas, chronic normobaric hypoxia promotes increased expression of the following kinases in the myocardium: PKCepsilon, PKCbetaII, PKCeta, CaMKII, p-ERK1/2, p-Akt, p-p38, HK-1, and HK-2. However, CNH does not promote enhanced expression of the AMPK and JNK kinases. Adaptation to hypoxia enhances HK-2 association with mitochondria and causes translocation of PKCdelta, PKCbetaII, and PKCeta to the mitochondria. It has been shown that PKCdelta, PKCepsilon, ERK1/2, and MEK1/2 are involved in the cardioprotective effect of chronic hypoxia. The role of other kinases in the cardioprotective effect of adaptation to hypoxia requires further research.
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Affiliation(s)
- N V Naryzhnaya
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Tomsk, Russia.
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9
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MondoA:MLX complex regulates glucose-dependent gene expression and links to circadian rhythm in liver and brain of the freeze-tolerant wood frog, Rana sylvatica. Mol Cell Biochem 2020; 473:203-216. [PMID: 32638259 DOI: 10.1007/s11010-020-03820-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/27/2020] [Indexed: 10/23/2022]
Abstract
The wood frog, Rana sylvatica, is one of only a few vertebrate species that display natural freeze tolerance. Frogs survive the freezing of about two-thirds of their body water as extracellular ice over the winter months. Multiple adaptations support freeze tolerance including metabolic rate depression and the production of huge amounts of glucose (often 200 mM or more) as a cryoprotectant that protects cells from freeze damage. To understand how high glucose levels affect gene expression, we studied MondoA, a glucose sensing transcription factor, and its partner MLX (Max-like protein) to assess their ability to modulate the expression of genes involved in glucose metabolism and circadian rhythm. Wood frog liver and brain tissues were analyzed, assessing protein levels, nuclear distribution, and DNA binding activity of MondoA:MLX during freezing (24 h at - 2.5 °C) and subsequent thawing (8 h returned to 5 °C), as compared with 5 °C controls. Downstream targets of MondoA:MLX were also evaluated: TXNIP (thioredoxin interacting protein), ARRDC4 (arrestin domain containing 4), HK-2 (hexokinase-2), PFKFB-3 (6-phosphofructo-2-kinase isozyme 3) and KLF-10 (Kruppel-like factor-10). Both KLF-10 and PFKFB-3 are also involved in circadian dependant regulation which was also explored in the current study via analysis of BMAL-1 (aryl hydrocarbon receptor nuclear translocator-like protein 1) and CLOCK (circadian locomotor output cycles kaput) proteins. Our data establish the MondoA-MLX complex as active under the hyperglycemic conditions in liver to regulate glucose metabolism and may also link to circadian rhythm in liver via KLF-10 and PFKFB-3 but not in brain.
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10
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Garcia SN, Guedes RC, Marques MM. Unlocking the Potential of HK2 in Cancer Metabolism and Therapeutics. Curr Med Chem 2020; 26:7285-7322. [PMID: 30543165 DOI: 10.2174/0929867326666181213092652] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/26/2018] [Accepted: 11/06/2018] [Indexed: 12/24/2022]
Abstract
Glycolysis is a tightly regulated process in which several enzymes, such as Hexokinases (HKs), play crucial roles. Cancer cells are characterized by specific expression levels of several isoenzymes in different metabolic pathways and these features offer possibilities for therapeutic interventions. Overexpression of HKs (mostly of the HK2 isoform) have been consistently reported in numerous types of cancer. Moreover, deletion of HK2 has been shown to decrease cancer cell proliferation without explicit side effects in animal models, which suggests that targeting HK2 is a viable strategy for cancer therapy. HK2 inhibition causes a substantial decrease of glycolysis that affects multiple pathways of central metabolism and also destabilizes the mitochondrial outer membrane, ultimately enhancing cell death. Although glycolysis inhibition has met limited success, partly due to low selectivity for specific isoforms and excessive side effects of the reported HK inhibitors, there is ample ground for progress. The current review is focused on HK2 inhibition, envisaging the development of potent and selective anticancer agents. The information on function, expression, and activity of HKs is presented, along with their structures, known inhibitors, and reported effects of HK2 ablation/inhibition. The structural features of the different isozymes are discussed, aiming to stimulate a more rational approach to the design of selective HK2 inhibitors with appropriate drug-like properties. Particular attention is dedicated to a structural and sequence comparison of the structurally similar HK1 and HK2 isoforms, aiming to unveil differences that could be explored therapeutically. Finally, several additional catalytic- and non-catalytic roles on different pathways and diseases, recently attributed to HK2, are reviewed and their implications briefly discussed.
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Affiliation(s)
- Sara N Garcia
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.,iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - Rita C Guedes
- iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - M Matilde Marques
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
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11
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Nedvedova I, Kolar D, Elsnicova B, Hornikova D, Novotny J, Kalous M, Pravenec M, Neckar J, Kolar F, Zurmanova JM. Mitochondrial genome modulates myocardial Akt/Glut/HK salvage pathway in spontaneously hypertensive rats adapted to chronic hypoxia. Physiol Genomics 2018; 50:532-541. [PMID: 29676955 DOI: 10.1152/physiolgenomics.00040.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recently we have shown that adaptation to continuous normobaric hypoxia (CNH) decreases myocardial ischemia/reperfusion injury in spontaneously hypertensive rats (SHR) and in a conplastic strain (SHR-mtBN). The protective effect was stronger in the latter group characterized by a selective replacement of the SHR mitochondrial genome with that of a more ischemia-resistant Brown Norway strain. The aim of the present study was to examine the possible involvement of the hypoxia inducible factor (HIF)-dependent pathway of the protein kinase B/glucose transporters/hexokinase (Akt/GLUT/HK) in this mitochondrial genome-related difference of the cardioprotective phenotype. Adult male rats were exposed for 3 wk to CNH ([Formula: see text] 0.1). The expression of dominant isoforms of Akt, GLUT, and HK in left ventricular myocardium was determined by real-time RT-PCR and Western blotting. Subcellular localization of GLUTs was assessed by quantitative immunofluorescence. Whereas adaptation to hypoxia markedly upregulated protein expression of HK2, GLUT1, and GLUT4 in both rat strains, Akt2 protein level was significantly increased in SHR-mtBN only. Interestingly, a higher content of HK2 was revealed in the sarcoplasmic reticulum-enriched fraction in SHR-mtBN after CNH. The increased activity of HK determined in the mitochondrial fraction after CNH in both strains suggested an increase of HK association with mitochondria. Interestingly, HIF1a mRNA increased and HIF2a mRNA decreased after CNH, the former effect being more pronounced in SHR-mtBN than in SHR. Pleiotropic effects of upregulated Akt2 along with HK translocation to mitochondria and mitochondria-associated membranes can potentially contribute to a stronger CNH-afforded cardioprotection in SHR-mtBN compared with progenitor SHR.
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Affiliation(s)
- Iveta Nedvedova
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - David Kolar
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - Barbara Elsnicova
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - Daniela Hornikova
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - Jiri Novotny
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - Martin Kalous
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
| | - Michal Pravenec
- Institute of Physiology of the Czech Academy of Sciences , Prague , Czech Republic
| | - Jan Neckar
- Institute of Physiology of the Czech Academy of Sciences , Prague , Czech Republic
| | - Frantisek Kolar
- Institute of Physiology of the Czech Academy of Sciences , Prague , Czech Republic
| | - Jitka M Zurmanova
- Department of Physiology, Faculty of Science, Charles University , Prague , Czech Republic
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12
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Mallet RT, Manukhina EB, Ruelas SS, Caffrey JL, Downey HF. Cardioprotection by intermittent hypoxia conditioning: evidence, mechanisms, and therapeutic potential. Am J Physiol Heart Circ Physiol 2018; 315:H216-H232. [PMID: 29652543 DOI: 10.1152/ajpheart.00060.2018] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The calibrated application of limited-duration, cyclic, moderately intense hypoxia-reoxygenation increases cardiac resistance to ischemia-reperfusion stress. These intermittent hypoxic conditioning (IHC) programs consistently produce striking reductions in myocardial infarction and ventricular tachyarrhythmias after coronary artery occlusion and reperfusion and, in many cases, improve contractile function and coronary blood flow. These IHC protocols are fundamentally different from those used to simulate sleep apnea, a recognized cardiovascular risk factor. In clinical studies, IHC improved exercise capacity and decreased arrhythmias in patients with coronary artery or pulmonary disease and produced robust, persistent, antihypertensive effects in patients with essential hypertension. The protection afforded by IHC develops gradually and depends on β-adrenergic, δ-opioidergic, and reactive oxygen-nitrogen signaling pathways that use protein kinases and adaptive transcription factors. In summary, adaptation to intermittent hypoxia offers a practical, largely unrecognized means of protecting myocardium from impending ischemia. The myocardial and perhaps broader systemic protection provided by IHC clearly merits further evaluation as a discrete intervention and as a potential complement to conventional pharmaceutical and surgical interventions.
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Affiliation(s)
- Robert T Mallet
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center , Fort Worth, Texas
| | - Eugenia B Manukhina
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center , Fort Worth, Texas.,Institute of General Pathology and Pathophysiology, Russian Academy of Medical Sciences , Moscow , Russian Federation.,School of Medical Biology South Ural State University , Chelyabinsk , Russian Federation
| | - Steven Shea Ruelas
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center , Fort Worth, Texas
| | - James L Caffrey
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center , Fort Worth, Texas
| | - H Fred Downey
- Department of Integrative Physiology and Anatomy, University of North Texas Health Science Center , Fort Worth, Texas.,School of Medical Biology South Ural State University , Chelyabinsk , Russian Federation
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13
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Nedvedova I, Kolar D, Neckar J, Kalous M, Pravenec M, Šilhavý J, Korenkova V, Kolar F, Zurmanova JM. Cardioprotective Regimen of Adaptation to Chronic Hypoxia Diversely Alters Myocardial Gene Expression in SHR and SHR-mt BN Conplastic Rat Strains. Front Endocrinol (Lausanne) 2018; 9:809. [PMID: 30723458 PMCID: PMC6350269 DOI: 10.3389/fendo.2018.00809] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 12/24/2018] [Indexed: 11/17/2022] Open
Abstract
Adaptation to continuous normobaric hypoxia (CNH) protects the heart against acute ischemia/reperfusion injury. Recently, we have demonstrated the infarct size-limiting effect of CNH also in hearts of spontaneously hypertensive rats (SHR) and in conplastic SHR-mtBN strain characterized by the selective replacement of the mitochondrial genome of SHR with that of more ischemia-resistant Brown Norway rats. Importantly, cardioprotective effect of CNH was more pronounced in SHR-mtBN than in SHR. Thus, here we aimed to identify candidate genes which may contribute to this difference between the strains. Rats were adapted to CNH (FiO2 0.1) for 3 weeks or kept at room air as normoxic controls. Screening of 45 transcripts was performed in left ventricles using Biomark Chip. Significant differences between the groups were analyzed by univariate analysis (ANOVA) and the genes contributing to the differences between the strains unmasked by CNH were identified by multivariate analyses (PCA, SOM). ANOVA with Bonferroni correction revealed that transcripts differently affected by CNH in SHR and SHR-mtBN belong predominantly to lipid metabolism and antioxidant defense. PCA divided four experimental groups into two main clusters corresponding to chronically hypoxic and normoxic groups, and differences between the strains were more pronounced after CNH. Subsequently, the following 14 candidate transcripts were selected by PCA, and confirmed by SOM analyses, that can contribute to the strain differences in cardioprotective phenotype afforded by CNH: Alkaline ceramidase 2 (Acer2), Fatty acid translocase (Cd36), Aconitase 1 (Aco1), Peroxisome proliferator activated receptor gamma (Pparg), Hemoxygenase 2 (Hmox2), Phospholipase A2 group IIA (Ppla2g2a), Dynamin-related protein (Drp), Protein kinase C epsilon (Pkce), Hexokinase 2 (Hk2), Sphingomyelin synthase 2 (Sgms2), Caspase 3 (Casp3), Mitofussin 1 (Mfn1), Phospholipase A2 group V (Pla2g5), and Catalase (Cat). Our data suggest that the stronger cardioprotective phenotype of conplastic SHR-mtBN strain afforded by CNH is associated with either preventing the drop or increasing the expression of transcripts related to energy metabolism, antioxidant response and mitochondrial dynamics.
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Affiliation(s)
- Iveta Nedvedova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - David Kolar
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Jan Neckar
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Martin Kalous
- Department of Cell Biology, Faculty of Science, Charles University, Prague, Czechia
| | - Michal Pravenec
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jan Šilhavý
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Vlasta Korenkova
- Institute of Biotechnology, Czech Academy of Sciences, Prague, Czechia
| | - Frantisek Kolar
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jitka M. Zurmanova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
- *Correspondence: Jitka M. Zurmanova
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14
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Kohutova J, Elsnicova B, Holzerova K, Neckar J, Sebesta O, Jezkova J, Vecka M, Vebr P, Hornikova D, Szeiffova Bacova B, Egan Benova T, Hlavackova M, Tribulova N, Kolar F, Novakova O, Zurmanova JM. Anti-arrhythmic Cardiac Phenotype Elicited by Chronic Intermittent Hypoxia Is Associated With Alterations in Connexin-43 Expression, Phosphorylation, and Distribution. Front Endocrinol (Lausanne) 2018; 9:789. [PMID: 30740090 PMCID: PMC6357219 DOI: 10.3389/fendo.2018.00789] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 12/14/2018] [Indexed: 12/31/2022] Open
Abstract
Remodeling of the cellular distribution of gap junctions formed mainly by connexin-43 (Cx43) can be related to the increased incidence of cardiac arrhythmias. It has been shown that adaptation to chronic intermittent hypobaric hypoxia (IHH) attenuates the incidence and severity of ischemic and reperfusion ventricular arrhythmias and increases the proportion of anti-arrhythmic n-3 polyunsaturated fatty acids (n-3 PUFA) in heart phospholipids. Wistar rats were exposed to simulated IHH (7,000 m, 8-h/day, 35 exposures) and compared with normoxic controls (N). Cx43 expression, phosphorylation, localization and n-3 PUFA proportion were analyzed in left ventricular myocardium. Compared to N, IHH led to higher expression of total Cx43, its variant phosphorylated at Ser368 [p-Cx43(Ser368)], which maintains "end to end" communication, as well as p-Cx43(Ser364/365), which facilitates conductivity. By contrast, expression of non-phosphorylated Cx43 and p-Cx43(Ser278/289), attenuating intercellular communication, was lower in IHH than in N. IHH also resulted in increased expression of protein kinase A and protein kinase G while casein kinase 1 did not change compared to N. In IHH group, which exhibited reduced incidence of ischemic ventricular arrhythmias, Cx43 and p-Cx43(Ser368) were more abundant at "end to end" gap junctions than in N group and this difference was preserved after acute regional ischemia (10 min). We further confirmed higher n-3 PUFA proportion in heart phospholipids after adaptation to IHH, which was even further increased by ischemia. Our results suggest that adaptation to IHH alters expression, phosphorylation and distribution of Cx43 as well as cardioprotective n-3PUFA proportion suggesting that the anti-arrhythmic phenotype elicited by IHH can be at least partly related to the stabilization of the "end to end" conductivity between cardiomyocytes during brief ischemia.
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Affiliation(s)
- Jana Kohutova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Barbara Elsnicova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Kristyna Holzerova
- Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Jan Neckar
- Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Ondrej Sebesta
- Laboratory of Confocal and Fluorescence Microscopy, Faculty of Science, Charles University, Prague, Czechia
| | - Jana Jezkova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Marek Vecka
- 4th Department of Internal Medicine, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Pavel Vebr
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Daniela Hornikova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
| | - Barbara Szeiffova Bacova
- Center of Experimental Medicine of the Slovak Academy of Sciences, Institute for Heart Research, Bratislava, Slovakia
| | - Tamara Egan Benova
- Center of Experimental Medicine of the Slovak Academy of Sciences, Institute for Heart Research, Bratislava, Slovakia
| | - Marketa Hlavackova
- Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Narcis Tribulova
- Center of Experimental Medicine of the Slovak Academy of Sciences, Institute for Heart Research, Bratislava, Slovakia
| | - Frantisek Kolar
- Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Olga Novakova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
- Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Jitka M. Zurmanova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czechia
- *Correspondence: Jitka M. Zurmanova
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