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Dearing C, Sanford E, Olmstead N, Morano R, Wulsin L, Myers B. Sex-specific cardiac remodeling in aged rats after adolescent chronic stress: associations with endocrine and metabolic factors. Biol Sex Differ 2024; 15:65. [PMID: 39180122 PMCID: PMC11342553 DOI: 10.1186/s13293-024-00639-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 08/07/2024] [Indexed: 08/26/2024] Open
Abstract
BACKGROUND Cardiovascular disease is a leading cause of death worldwide. Rates of cardiovascular disease vary both across the lifespan and between sexes. While multiple factors, including adverse life experiences, impact the development and progression of cardiovascular disease, the potential interactions of biological sex and stress history on the aged heart are unknown. To this end, we examined sex- and stress-specific impacts on left ventricular hypertrophy (VH) after aging. We hypothesized that early-life chronic stress exposure impacts behavioral and physiologic responses that predict cardiac remodeling in a sex-specific manner. METHODS Histological analysis was conducted on hearts of male and female rats previously exposed to chronic variable stress during the late adolescent period (postnatal days 43-62). These animals were challenged with a forced swim test and a glucose tolerance test before aging to 15 months and again being challenged. Predictive analyses were then used to isolate factors that relate to cardiac remodeling among these groups. RESULTS Early-life chronic stress impacted cardiac remodeling in a sex-specific manner. Among rats with a history of chronic stress, females had increased concentric VH. However, there were few associations within the female groups among individual behavioral and physiologic parameters and cardiac remodeling. While males as a group did not have VH after chronic stress, they exhibited multiple individual associations with cardiac susceptibility. Passive coping in young males and active coping in aged males related to VH in a stress history-dependent manner. Moreover, baseline corticosterone positively correlated with VH in unstressed males, while chronically-stressed males had positive correlations between VH and visceral adiposity. CONCLUSIONS These results indicate that females as a group are uniquely susceptible to the effects of early-life stress on cardiac remodeling later in life. Conversely, males have more individual differences in vulnerability, where susceptibility to cardiac remodeling relates to endocrine, metabolic, and behavioral measures depending on stress history. These results ultimately support a framework for assessing cardiovascular risk based on biological sex and prior adverse experiences.
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Affiliation(s)
- Carley Dearing
- Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Ella Sanford
- Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | | | - Rachel Morano
- Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - Lawson Wulsin
- Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - Brent Myers
- Biomedical Sciences, Colorado State University, Fort Collins, CO, USA.
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Chung E, Diffee GM. Moderate intensity, but not high intensity, treadmill exercise training alters power output properties in myocardium from aged rats. J Gerontol A Biol Sci Med Sci 2012; 67:1178-87. [PMID: 22843668 PMCID: PMC3636676 DOI: 10.1093/gerona/gls146] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 05/15/2012] [Indexed: 11/14/2022] Open
Abstract
Aging is characterized by a progressive decline in cardiac function, but endurance exercise training has been shown to retard a number of deleterious effects of aging. However, underlying mechanisms by which exercise training improves age-related decrements in myocardial contractile function are not well understood. The purpose of this study was to determine the effects of exercise training on power output properties in permeablized (skinned) myocytes of old rats. Thirty-month-old rats were divided into sedentary control (C) and groups undergoing 11 weeks of treadmill exercise training at moderate intensity (MI) and at high intensity (HI). Peak power output normalized to maximal force was significantly increased in MI but not in HI compared to C with significant increases in atrial myosin light chain 1 in ventricle. These results suggest that MI exercise training is beneficial as a significant increase was seen in the ability of the myocardium to do work, but this effect was not seen with HI training.
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Affiliation(s)
- Eunhee Chung
- Balke Biodynamics Laboratory, Department of Kinesiology,University of Wisconsin-Madison, Madison, Wisconsin 53706-1121, USA
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Morris C, Bourne PA, Eldemire-Shearer D, McGrowder DA. Social determinants of physical exercise in older men in Jamaica. NORTH AMERICAN JOURNAL OF MEDICAL SCIENCES 2012; 2:87-96. [PMID: 22624120 PMCID: PMC3354440 DOI: 10.4297/najms.2010.287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Background: Background: Physical activity interventions have been demonstrated to improve health-related quality of life and to be of special benefit to older adults with specific chronic conditions including arthritis, hypertension, diabetes mellitus, and heart disease. Aim: This study examined the extent and social determinants of physical exercise in elderly men in Jamaica. Materials and Methods: A sample of 2,000 men 55 years of age and older was extracted from a total of 33,674 males in the parish of St. Catherine. A 132-item questionnaire was used to collect the data. A stratified random sampling technique was used to draw the sample. Descriptive statistics were used to provide background information on the sub-sample, and logistic regressions were utilized to model physical exercise. Results: Of the respondents, 55.4% indicated good health status, 51.0% lived in rural areas; 10.4% had moderate to high functional dependence and 67.3% reported that they did some form of physical exercise. Of those who indicated involvement in physical exercise (n = 1,345), 77.2% jogged, ran, and/or walked; 13.3% did aerobics; 4.7% swam; 2.0% cycled and 0.6% did push-ups or sit-ups. The variables that predicted being engaged in physical exercise were education; age of respondents; current good health status; household head; health plan; employment status, and social support. Conclusion: Most of the elderly men were engaged in some form of physical activity and had good health. Age and good health status were the most influential social determinants of physical exercise. However, effective interventions to promote physical activity in older men in Caribbean countries such as Jamaica deserve wide implementation.
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Affiliation(s)
- Chloe Morris
- Department of Community Health and Psychiatry, Faculty of Medical Sciences, The University of the West Indies, Mona Campus, Kingston 7, Jamaica
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Groban L, Jobe H, Lin M, Houle T, Kitzman DA, Sonntag W. Effects of short-term treadmill exercise training or growth hormone supplementation on diastolic function and exercise tolerance in old rats. J Gerontol A Biol Sci Med Sci 2008; 63:911-20. [PMID: 18840795 DOI: 10.1093/gerona/63.9.911] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Whether the lusitropic potential of short-term exercise in aged rats is linked to an augmentation in the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and an alteration in the cardiac renin angiotensin system (RAS) is unknown. Old (28-month-old) male, Fischer 344xBrown Norway rats were randomized to 4 weeks of GH supplementation (300 microg subcutaneous, twice daily) or 4 weeks of treadmill running, or were used as sedentary controls. Six-month-old rats, sedentary or exercised, were used as young controls. Training improved exercise capacity in old animals. Exercise and GH attenuated age-related declines in myocardial relaxation despite an exercise-induced suppression of IGF-1. The regulatory protein, sarcoplasmic Ca2+ adenosine triphosphatase (SERCA2), increased with exercise but not GH. Among aged rats, the cardiac RAS was not altered by training or GH. Thus, the signaling pathway underlying the lusitropic benefit of short-term habitual exercise in the aged rat may be distinct from GH-mediated benefits and independent of the cardiac RAS.
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Affiliation(s)
- Leanne Groban
- Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1009, USA.
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Tatsuguchi M, Hiratsuka E, Machida S, Nishikawa T, Imamura SI, Shimizu S, Nishimura M, Komuro I, Furutani Y, Furutani M, Nagao H, Komatsu K, Kasanuki H, Matsuoka R. Swimming exercise in infancy has beneficial effect on the hearts in cardiomyopathic Syrian hamsters. J Muscle Res Cell Motil 2004; 25:69-76. [PMID: 15160490 DOI: 10.1023/b:jure.0000021353.82449.9e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The phenotypic expression of cardiomyopathy is greatly influenced by extrinsic factors other than intrinsic genetic defects, such as environmental stress. Exercise is assumed to be an important extrinsic factor, since sudden death is sometimes seen during exercise in young patients with hypertrophic cardiomyopathy (HCM). However, the long-term effects of mild exercise on phenotypic expression in cardiomyopathy remain unclear. To evaluate the effects of exercise performed during infancy or adolescence in cardiomyopathic patients, cardiomyopathic Syrian hamsters (BIO14.6) were subjected to swimming. BIO14.6 and age-matched congenic normal hamsters (CN) as controls were divided into three groups: sedentary (Sed), and trained during infancy (Inf) and during adolescence (Ado). Histological and biochemical analysis of 41-week-old hamsters revealed that (1) the relative level of beta-myosin heavy chain mRNA was significantly lower in the Inf group than in the Sed and Ado groups of BIO14.6. The level in the Inf group of BIO14.6 was compatible with that in the age-matched Sed group of the CN strain; (2) in BIO14.6, degenerative mitochondrial change in the cardiomyocytes was not seen in the Inf group while it was common in the Sed and Ado groups; (3) calcineurin phosphatase activity in the swimming group in 10-week-old CN was significantly higher than that of the age-matched sedentary group, and was as much as that of the swimming and sedentary groups in 10- and 41-week-old BIO14.6.
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Affiliation(s)
- Mariko Tatsuguchi
- Department of Cardiology, Heart Institute of Japan, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
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Frayon S, Cueille C, Davicco MJ, Coxam V, Barlet JP, Garel JM. Increased expression of SERCA2 mRNA in hearts of genetically obese Zucker rats after a moderate treadmill running. Sci Sports 2004. [DOI: 10.1016/s0765-1597(03)00158-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Iemitsu M, Miyauchi T, Maeda S, Tanabe T, Takanashi M, Matsuda M, Yamaguchi I. Exercise training improves cardiac function-related gene levels through thyroid hormone receptor signaling in aged rats. Am J Physiol Heart Circ Physiol 2004; 286:H1696-705. [PMID: 14704232 DOI: 10.1152/ajpheart.00761.2003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exercise training improves the aging-induced downregulation of myosin heavy chain (MHC) and sarcoplasmic reticulum (SR) Ca(2+)-ATPase, which participate in the regulation of cardiac contraction and relaxation. Thyroid hormone receptor (TR), a transcriptional activator, affected the regulation of gene expression of MHC and SR Ca(2+)-ATPase. We hypothesized that myocardial TR signaling contributes to a molecular mechanism of exercise training-induced improvement of MHC and SR Ca(2+)-ATPase genes with cardiac function in old age. We investigated whether TR signaling and gene expression of MHC and SR Ca(2+)-ATPase in the aged heart are affected by exercise training, using the hearts of sedentary young rats (4 mo old), sedentary aged rats (23 mo old), and trained aged rats (23 mo old, swimming training for 8 wk). Trained aged rats showed improvement in cardiac function. Expression of TR-alpha1 and TR-beta1 proteins in the heart were significantly lower in sedentary aged rats than in sedentary young rats and were significantly higher in trained aged rats than in sedentary aged rats. The activity of TR DNA binding to the transcriptional regulatory region in the alpha-MHC and SR Ca(2+)-ATPase genes and the mRNA and protein expression of alpha-MHC and SR Ca(2+)-ATPase in the heart and plasma 3,3'-triiodothyronine and thyroxine levels were altered in association with changes in the myocardial TR protein levels. These findings suggest that exercise training improves the aging-induced downregulation of myocardial TR signaling-mediated transcription of MHC and SR Ca(2+)-ATPase genes, thereby contributing to the improvement of cardiac function in trained aged hearts.
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Affiliation(s)
- Motoyuki Iemitsu
- Cardiovascular Division, Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
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Mace LC, Palmer BM, Brown DA, Jew KN, Lynch JM, Glunt JM, Parsons TA, Cheung JY, Moore RL. Influence of age and run training on cardiac Na+/Ca2+ exchange. J Appl Physiol (1985) 2003; 95:1994-2003. [PMID: 12882992 DOI: 10.1152/japplphysiol.00551.2003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Effects of age and training on myocardial Na+/Ca2+ exchange were examined in young sedentary (YS; 14-15 mo), aged sedentary (AS; 27-31 mo), and aged trained (AT; 8- to 11-wk treadmill run training) male Fischer Brown Norway rats. Whole heart performance and isolated cardiocyte Na+/Ca2+ exchange characteristics were measured. At the whole heart level, a small but significant slowing of late isovolumic left ventricular (LV) relaxation, which may be indicative of altered Na+/Ca2+ exchange activity, was seen in hearts from AS rats. This subtle impairment in relaxation was not observed in hearts from AT rats. At the single-cardiocyte level, late action potential duration was prolonged, resting membrane potential was more positive, and overshoot potential was greater in cardiocytes from AS rats than from YS rats (P < 0.05). Training did not influence any of these age-related action potential characteristics. In electrically paced cardiocytes, neither shortening nor intracellular Ca2+ concentration ([Ca2+]i) dynamics was influenced by age or training. Similarly, neither age nor training influenced the rate of [Ca2+]i clearance via forward (Nain+ /Caout2+) Na+/Ca2+ exchange after caffeine-induced Ca2+ release from the sarcoplasmic reticulum or cardiac Na+/Ca2+ exchanger protein (NCX1) expression. However, when whole cell patch-clamp techniques combined with fluorescence microscopy were used to evaluate the ability of Na+/Ca2+ exchange to alter cytosolic [Ca2+] ([Ca2+]c) under conditions where membrane potential (Vm) and internal and external [Na+] and [Ca2+] could be controlled, we observed age-associated increases in forward Na+/Ca2+ exchange-mediated [Ca2+]c clearance (P < 0.05) that were not influenced by training. The age-related increase in forward Na+/Ca2+ exchange activity provides a hypothetical explanation for the late action potential prolongation observed in this study.
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Affiliation(s)
- Lisa C Mace
- Department of Integrative Physiology, University of Colorado at Boulder, Boulder, Colorado 80309-0354, USA
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Jin H, Yang R, Li W, Lu H, Ryan AM, Ogasawara AK, Van Peborgh J, Paoni NF. Effects of exercise training on cardiac function, gene expression, and apoptosis in rats. Am J Physiol Heart Circ Physiol 2000; 279:H2994-3002. [PMID: 11087257 DOI: 10.1152/ajpheart.2000.279.6.h2994] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study determined the effects of exercise training on cardiac function, gene expression, and apoptosis. Rats exposed to a regimen of treadmill exercise for 13 wk had a significant increase in cardiac index and stroke volume index and a concomitant decrease in systemic vascular resistance compared with both age-matched and body weight-matched sedentary controls in the conscious state at rest. In exercise-trained animals, there was no change in the expression of several marker genes known to be associated with pathological cardiac adaptation, including atrial natriuretic factor, beta-myosin heavy chain, alpha-skeletal and smooth muscle actins, and collagens I and III. Exercise training, however, produced a significant induction of alpha-myosin heavy chain, which was not observed in rats with myocardial infarction. No histological features of cardiac apoptosis were observed in the treadmill-trained rats. In contrast, apoptotic myocytes were detected in animals with myocardial infarction. In summary, exercise training improves cardiac function without evidence of cardiac apoptosis and produces a pattern of cardiac gene expression distinct from pathological cardiac adaptation.
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Affiliation(s)
- H Jin
- Department of Cardiovascular Research, Genentech Incorporated, South San Francisco, California 94080, USA
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