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da Silva E, Natali AJ, da Silva MF, Gomes GDJ, da Cunha DNQ, Toledo MM, Drummond FR, Ramos RMS, Dos Santos EC, Novaes RD, de Oliveira LL, Maldonado IRDSC. Swimming training attenuates the morphological reorganization of the myocardium and local inflammation in the left ventricle of growing rats with untreated experimental diabetes. Pathol Res Pract 2016; 212:325-34. [PMID: 26896925 DOI: 10.1016/j.prp.2016.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 12/19/2015] [Accepted: 02/01/2016] [Indexed: 01/27/2023]
Abstract
Diabetic cardiomyopathy is associated with cardiac remodeling, myocardial dysfunction, low-grade inflammation, and reduced cardiac adiponectin in patients with type 1 diabetes mellitus (T1DM). Alternatively, physical exercise is an important strategy for the management of diabetes. This study aimed to investigate the influence of low-intensity swimming training in cardiac cytokines, structural remodeling, and cardiomyocyte contractile dysfunction in growing rats with untreated experimental DM. Thirty-day-old male Wistar rats were divided into four groups (n=14, per group): sedentary control (SC), exercised control (EC), sedentary diabetic (SD), and exercised diabetic (ED). Diabetes was induced by streptozotocin (60 mg kg(-1), i.p.). Animals from exercised groups swam (5 days/week, 90 min/day, loading up to 5% body weight around the animal's chest) for 8 weeks. The left ventricle (LV) was removed for molecular, morphological, and cardiomyocyte mechanical analysis. Diabetic animals presented cardiac remodeling with myocardial histoarchitectural disorganization, fibrosis, and necrosis. The capillary density was lower in diabetic animals. LV cardiomyocytes from diabetic animals exhibited more prolonged time to the peak of contraction and time to half relaxation than those from control animals. The cardiac levels of interleukin 10, nitric oxide, and total and high molecular weight (HMW) adiponectin were significantly decreased in diabetic animals. Exercise training reduced the level of TNF-α, increased capillary density, and attenuated the histopathological parameters assessed in diabetic rats. In conclusion, the cardiac structural remodeling coexists with reduced levels of total and HMW adiponectin, inflammation, and cardiomyocyte contractility dysfunction in experimental DM. More important, low-intensity swimming training attenuates part of these pathological changes, indicating the beneficial role for exercise in untreated T1DM.
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Affiliation(s)
- Edson da Silva
- Department of General Biology, Federal University of Viçosa, Viçosa, MG, Brazil; Department of Basic Sciences, Federal University of Jequitinhonha and Mucuri Valleys, Diamantina, MG, Brazil.
| | - Antônio José Natali
- Department of Physical Education, Federal University of Viçosa, Viçosa, MG, Brazil
| | | | - Gilton de Jesus Gomes
- Department of Physical Education, Federal University of Viçosa, Viçosa, MG, Brazil; Department of Physical Education, Federal University of Jequitinhonha and Mucuri Valleys, Diamantina, MG, Brazil
| | | | | | - Filipe Rios Drummond
- Department of Physical Education, Federal University of Viçosa, Viçosa, MG, Brazil
| | | | - Eliziária Cardoso Dos Santos
- Department of General Biology, Federal University of Viçosa, Viçosa, MG, Brazil; Faculty of Medicine, Federal University of Jequitinhonha and Mucuri Valleys, Diamantina, MG, Brazil
| | - Rômulo Dias Novaes
- Department of General Biology, Federal University of Viçosa, Viçosa, MG, Brazil; Biomedical Sciences Institute, Federal University of Alfenas, MG, Brazil
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Silva E, Natali AJ, Silva MF, Gomes GJ, Cunha DN, Ramos RM, Toledo MM, Drummond FR, Belfort FG, Novaes RD, Maldonado IR. Ventricular remodeling in growing rats with experimental diabetes: The impact of swimming training. Pathol Res Pract 2013; 209:618-26. [DOI: 10.1016/j.prp.2013.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 05/31/2013] [Accepted: 06/25/2013] [Indexed: 01/27/2023]
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Stehno-Bittel L. Organ-based response to exercise in type 1 diabetes. ISRN ENDOCRINOLOGY 2012; 2012:318194. [PMID: 23251813 PMCID: PMC3518066 DOI: 10.5402/2012/318194] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 11/14/2012] [Indexed: 12/16/2022]
Abstract
While significant research has clearly identified sedentary behavior as a risk factor for type 2 diabetes and its subsequent complications, the concept that inactivity could be linked to the complications associated with type 1 diabetes (T1D) remains underappreciated. This paper summarizes the known effects of exercise on T1D at the tissue level and focuses on the pancreas, bone, the cardiovascular system, the kidneys, skeletal muscle, and nerves. When possible, the molecular mechanisms underlying the benefits of exercise for T1D are elucidated. The general benefits of increased activity on health and the barriers to increased exercise specific to people with T1D are discussed.
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Affiliation(s)
- Lisa Stehno-Bittel
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, KS 66160, USA
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Loganathan R, Novikova L, Boulatnikov IG, Smirnova IV. Exercise-induced cardiac performance in autoimmune (type 1) diabetes is associated with a decrease in myocardial diacylglycerol. J Appl Physiol (1985) 2012; 113:817-26. [PMID: 22797313 DOI: 10.1152/japplphysiol.01626.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
One of the fundamental biochemical defects underlying the complications of diabetic cardiovascular system is elevation of diacylglycerol (DAG) and its effects on protein kinase C (PKC) signaling. It has been noted that exercise training attenuates poor cardiac performance in Type 1 diabetes. However, the role of PKC signaling in exercise-induced alleviation of cardiac abnormalities in diabetes is not clear. We investigated the possibility that exercise training modulates PKC-βII signaling to elicit its beneficial effects on the diabetic heart. bio-breeding diabetic resistant rats, a model reminiscent of Type 1 diabetes in humans, were randomly assigned to four groups: 1) nonexercised nondiabetic (NN); 2) nonexercised diabetic (ND); 3) exercised nondiabetic; and 4) exercised diabetic. Treadmill training was initiated upon the onset of diabetes. At the end of 8 wk, left ventricular (LV) hemodynamic assessment revealed compromised function in ND compared with the NN group. LV myocardial histology revealed increased collagen deposition in ND compared with the NN group, while electron microscopy showed a reduction in the viable mitochondrial fraction. Although the PKC-βII levels and activity were unchanged in the diabetic heart, the DAG levels were increased. With exercise training, the deterioration of LV structure and function in diabetes was attenuated. Notably, improved cardiac performance in training was associated with a decrease in myocardial DAG levels in diabetes. Exercise-induced benefits on cardiac performance in diabetes may be mediated by prevention of an increase in myocardial DAG levels.
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Affiliation(s)
- Rajprasad Loganathan
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, Kansas 66160-7601, USA
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Exercise increases insulin content and basal secretion in pancreatic islets in type 1 diabetic mice. EXPERIMENTAL DIABETES RESEARCH 2011; 2011:481427. [PMID: 21912535 PMCID: PMC3170797 DOI: 10.1155/2011/481427] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 05/17/2011] [Indexed: 11/28/2022]
Abstract
Exercise appears to improve glycemic control for people with type 1 diabetes (T1D). However, the mechanism responsible for this improvement is unknown. We hypothesized that exercise has a direct effect on the insulin-producing islets. Eight-week-old mice were divided into four groups: sedentary diabetic, exercised diabetic, sedentary control, and exercised control. The exercised groups participated in voluntary wheel running for 6 weeks. When compared to the control groups, the islet density, islet diameter, and β-cell proportion per islet were significantly lower in both sedentary and exercised diabetic groups and these alterations were not improved with exercise. The total insulin content and insulin secretion were significantly lower in sedentary diabetics compared to controls. Exercise significantly improved insulin content and insulin secretion in islets in basal conditions. Thus, some improvements in exercise-induced glycemic control in T1D mice may be due to enhancement of insulin content and secretion in islets.
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Al-Jarrah M, Matalka I, Aseri HA, Mohtaseb A, Smirnova IV, Novikova L, Stehno-Bittel L, Alkhateeb A. Exercise training prevents endometrial hyperplasia and biomarkers for endometrial cancer in rat model of type 1 diabetes. J Clin Med Res 2011; 2:207-14. [PMID: 21629542 PMCID: PMC3104659 DOI: 10.4021/jocmr444e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2010] [Indexed: 12/13/2022] Open
Abstract
Background Endometrial cancer is one of the most common types of gynecologic cancers. The ability of exercise to reduce the risk of endometrial cancer in women with type 2 diabetes has been established, but no studies have examined this link in type 1 diabetes.A randomized, controlled animal study was designed using a standard rat model of type 1 diabetes. The goal of this study was to investigate the ability of exercise to prevent increased levels of endometrial cancer biomarkers, estrogen receptor (ERα) and p16, and endometrial hyperplasia associated with diabetes. Methods Forty female rats were randomized into four groups: sedentary control, exercise control, sedentary or exercised diabetic. Diabetes was induced by alloxan injection. A 4-week treadmill training program was initiated with the development of diabetes. Endometrial tissues were evaluated for hyperplasia and ERα and p16 levels and subcellular localization using microscopy. Results Severe diabetes lead to hyperplasia in the endometrial tissue in 70% of sedentary diabetic rats. Exercise-trained diabetic rats and the non-diabetic rats displayed no hyperplasia. The expression of ERα increased significantly (p < 0.02) while the expression level of p16 decreased significantly (p < 0.04) in the diabetic sedentary group compared to the non-diabetic groups. Exercise training led to a reversal in the percentage of p16 and ERα positive cells in diabetic rats. Conclusions Severe diabetes leads to hyperplasia of the endometrial tissue and increased ERα levels and decreased p16 levels in rats, which can be prevented with aerobic exercise. Keywords Diabetes; Estrogen receptor alpha; P16; Endometrial hyperplasia; Endometrial cancer; Exercise
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Affiliation(s)
- Muhammed Al-Jarrah
- Department of Allied Medical Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Jordan
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Gupte AA, Bomhoff GL, Touchberry CD, Geiger PC. Acute heat treatment improves insulin-stimulated glucose uptake in aged skeletal muscle. J Appl Physiol (1985) 2011; 110:451-7. [PMID: 21148343 PMCID: PMC3043783 DOI: 10.1152/japplphysiol.00849.2010] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 12/02/2010] [Indexed: 12/18/2022] Open
Abstract
Aging is associated with insulin resistance and decreased insulin-stimulated glucose uptake into skeletal muscle. Although the mechanisms underlying age-related insulin resistance are not clearly defined, impaired defense against inflammation and tissue oxidative stress are likely causes. Heat shock proteins (HSPs) have been shown to protect tissue from oxidative stress and inhibit the activation of stress kinases such as JNK, known to interfere with the insulin signaling pathway. While the induction of HSPs via chronic heat treatment has been shown to protect skeletal muscle from obesity-related insulin resistance, the ability of heat treatment to improve insulin action in aged skeletal muscle is not known. In the present study, one bout of in vivo heat treatment applied to 24-mo-old Fischer 344 rats improved insulin-stimulated glucose uptake after 24 h in slow-twitch soleus muscles. In vitro heat treatment applied to young (3-mo-old) and aged (24-mo-old) soleus muscles increased expression of HSP72 and inhibited anisomycin-induced activation of JNK. In contrast, heat treatment had no effect on p38 MAPK, a MAPK strongly activated with anisomycin. Prior inhibition of HSP72 transcription with the pharmacological inhibitor KNK437 eliminated the ability of heat treatment to blunt JNK activation. This suggests that the ability of heat treatment to inhibit JNK activation in skeletal muscle is dependent on increased HSP72 expression. In conclusion, an acute bout of heat treatment can increase insulin-stimulated glucose uptake in aged skeletal muscle, with the underlying mechanism likely to be HSP72-mediated JNK inhibition.
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Affiliation(s)
- Anisha A Gupte
- Dept. of Molecular and Integrative Physiology, Univ. of Kansas Medical Center, MS 3043, 3901 Rainbow Blvd., Kansas City, KS 66160, USA
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Howarth FC, Almugaddum FA, Qureshi MA, Ljubisavljevic M. The effects of heavy long-term exercise on ventricular myocyte shortening and intracellular Ca2+ in streptozotocin-induced diabetic rat. J Diabetes Complications 2010; 24:278-85. [PMID: 19395278 DOI: 10.1016/j.jdiacomp.2009.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2008] [Revised: 02/09/2009] [Accepted: 03/11/2009] [Indexed: 11/24/2022]
Abstract
OBJECTIVE This study investigated whether exercise training, initiated at the onset of diabetes, could preserve the contractile properties of ventricular myocytes. RESEARCH DESIGN AND METHODS The effects of a heavy exercise training program on shortening and intracellular Ca(2+) in unloaded ventricular myocytes from streptozotocin (STZ)-induced diabetic rats were examined. Animals were divided into four groups: control sedentary (CS), diabetic sedentary (DS), control heavy exercise (CHE), and diabetic heavy exercise (DHE). Exercise protocol: 5x60 min/week, 18 m/min, 5% gradient. Exercise training began 1 week after STZ treatment and continued for 12-23 (mean 17.5) weeks. RESULTS Diabetes induced prolongation of time-to-peak (TPK) shortening (124+/-2 ms in DS compared to 97+/-2 ms in CS rats), which was further increased by exercise (133+/-3 ms in DHE and 112+/-2 ms in CHE myocytes). Diabetes had no significant effects on time-to-half (THALF) relaxation of shortening (61+/-2 ms in DS compared to 56+/-2 ms in CS myocytes). Exercise induced significant prolongation of THALF in control (66+/-3 ms) but not in diabetic (69+/-3 ms) myocytes. Diabetes, though not exercise, significantly prolonged TPK (76+/-3 ms in DS compared to 64+/-2 ms in CS) and THALF recovery (160+/-5 ms in DS compared to 118+/-4 ms in CS) of the Ca(2+) transient. Neither diabetes nor exercise had significant effects on the amplitude of myocyte shortening and the Ca(2+) transient. CONCLUSIONS Heavy long-term exercise alters the dynamics but not the amplitude of unloaded myocyte contraction in the STZ-induced diabetic rat.
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MESH Headings
- Animals
- Calcium/metabolism
- Cell Size
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Experimental/physiopathology
- Heart Ventricles/metabolism
- Heart Ventricles/pathology
- Heart Ventricles/physiopathology
- Intracellular Space/metabolism
- Male
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- Myocytes, Cardiac/physiology
- Physical Conditioning, Animal/adverse effects
- Physical Conditioning, Animal/physiology
- Physical Exertion/physiology
- Rats
- Rats, Wistar
- Streptozocin
- Time Factors
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Affiliation(s)
- Frank Christopher Howarth
- Department of Physiology, Faculty of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, UAE.
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Measures of bulbar and spinal motor function, muscle innervation, and mitochondrial function in ALS rats. Behav Brain Res 2010; 211:48-57. [PMID: 20211206 DOI: 10.1016/j.bbr.2010.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 02/19/2010] [Accepted: 03/02/2010] [Indexed: 01/31/2023]
Abstract
Symptom onset in amyotrophic lateral sclerosis (ALS) may occur in the muscles of the limbs (spinal onset) or those of the head and neck (bulbar onset). Most preclinical studies have focused on spinal symptoms, despite the prevalence of and increased morbidity and mortality associated with bulbar disease. We measured lick rhythm and tongue force to evaluate bulbar disease in the SOD1-G93A rat model of familial ALS. Body weight and grip strength were measured concomitantly. Testing spanned the early (maturation), middle (pre-symptomatic), and late (symptomatic and end-stage) phases of the disease. We measured a persistent tongue motility deficit that became apparent in the early phase of the disease, providing behavioral evidence of bulbar pathology. At end-stage, however, cytochrome oxidase (CO) activity was normal in the hypoglossal nucleus, and in the tongue, neuromuscular innervation, citrate synthase (CS) protein levels and activity, and uncoupling protein 3 (UCP3) protein levels remained unchanged. Interestingly, significant denervation and atrophy were evident in the end-stage sternomastoid muscle, providing peripheral anatomical evidence of bulbar pathology. Changes in body weight and grip strength occurred in the late phase of the disease. Extensive atrophy and denervation were observed in the end-stage gastrocnemius muscle. In contrast to our findings in the tongue, CS protein levels were decreased in the extensor digitorum longus (EDL) and soleus, although CS activity was maintained or increased. UCP3 protein was decreased also in the EDL. These data provide evidence of differential effects in muscles that were more or less affected by disease.
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Gupte AA, Bomhoff GL, Swerdlow RH, Geiger PC. Heat treatment improves glucose tolerance and prevents skeletal muscle insulin resistance in rats fed a high-fat diet. Diabetes 2009; 58:567-78. [PMID: 19073766 PMCID: PMC2646055 DOI: 10.2337/db08-1070] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Heat treatment and overexpression of heat shock protein 72 (HSP72) have been shown to protect against high-fat diet-induced insulin resistance, but little is known about the underlying mechanism or the target tissue of HSP action. The purpose of this study is to determine whether in vivo heat treatment can prevent skeletal muscle insulin resistance. RESEARCH DESIGN AND METHODS Male Wistar rats were fed a high-fat diet (60% calories from fat) for 12 weeks and received a lower-body heat treatment (41 degrees C for 20 min) once per week. RESULTS Our results show that heat treatment shifts the metabolic characteristics of rats on a high-fat diet toward those on a standard diet. Heat treatment improved glucose tolerance, restored insulin-stimulated glucose transport, and increased insulin signaling in soleus and extensor digitorum longus (EDL) muscles from rats fed a high-fat diet. Heat treatment resulted in decreased activation of Jun NH2-terminal kinase (JNK) and inhibitor of kappaB kinase (IKK-beta), stress kinases implicated in insulin resistance, and upregulation of HSP72 and HSP25, proteins previously shown to inhibit JNK and IKK-beta activation, respectively. Mitochondrial citrate synthase and cytochrome oxidase activity decreased slightly with the high-fat diet, but heat treatment restored these activities. Data from L6 cells suggest that one bout of heat treatment increases mitochondrial oxygen consumption and fatty acid oxidation. CONCLUSIONS Our results indicate that heat treatment protects skeletal muscle from high-fat diet-induced insulin resistance and provide strong evidence that HSP induction in skeletal muscle could be a potential therapeutic treatment for obesity-induced insulin resistance.
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Affiliation(s)
- Anisha A Gupte
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, USA
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Effects of varying intensity exercise on shortening and intracellular calcium in ventricular myocytes from streptozotocin (STZ)-induced diabetic rats. Mol Cell Biochem 2008; 317:161-7. [PMID: 18553174 DOI: 10.1007/s11010-008-9844-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Accepted: 06/05/2008] [Indexed: 10/21/2022]
Abstract
This study examined the influence of two intensities of exercise on ventricular myocyte shortening and intracellular calcium in the streptozotocin (STZ)-induced diabetic rat. Animals were divided into four groups: control sedentary (CS), diabetic sedentary (DS), diabetic light exercise (DLE; 5 x 30 min/week, 9 m/min) and diabetic moderate exercise (DME; 5 x 30 min/week, 18 m/min) and the exercise programme started 2 months after STZ treatment. Time to peak (TPK) shortening was prolonged in myocytes from DS (112.1 +/- 2.5 ms) compared to CS (98.1 +/- 2.1 ms) rats and was not additionally altered by either light (117.0 +/- 2.1 ms) or moderate (115.4 +/- 2.0 ms) exercise. TPK of the Ca(2+) transient was not significantly altered by STZ treatment (69.4 +/- 2.4 ms) but was prolonged by light (79.8 +/- 3.5 ms) and moderate (76.6 +/- 2.9 ms) exercise compared to CS (65.5 +/- 2.7 ms). Data from this study suggest that the chosen intensities of exercise were ineffective in modulating the dynamics of cardiac muscle contraction and reversing the deleterious effects of diabetes on heart-muscle contraction.
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Loganathan R, Bilgen M, Al-Hafez B, Zhero SV, Alenezy MD, Smirnova IV. Exercise training improves cardiac performance in diabetes: in vivo demonstration with quantitative cine-MRI analyses. J Appl Physiol (1985) 2007; 102:665-72. [PMID: 17082374 DOI: 10.1152/japplphysiol.00521.2006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Diabetic cardiomyopathy is a distinct myocardial complication of the catabolic state of untreated insulin-dependent diabetes mellitus in the streptozotocin-induced diabetic rat. Exercise training has long been utilized as an effective adjunct to pharmacotherapy in the management of the diabetic heart. However, the in vivo functional benefit(s) of the training programs on cardiac cycle events in diabetes are poorly understood. In this study, we used three groups of Sprague-Dawley rats (sedentary control, sedentary diabetic, and exercised diabetic) to assess the effects of endurance training on the left ventricular (LV) cardiac cycle events in diabetes. At the end of 9 wk of exercise training, noninvasive cardiac functional evaluation was performed by using high-resolution magnetic resonance imaging (9.4 T). An ECG-gated cine imaging protocol was used to capture the LV cardiac cycle events through 10 equally incremented phases. The cardiac cycle phase volumetric profiles showed favorable functional changes in exercised diabetic group, including a prevention of decreased end-diastolic volume and attenuation of increased end-systolic volume that accompanies sedentary diabetes. The defects in LV systolic flow velocity, acceleration, and jerk associated with sedentary diabetes were restored toward control levels in the trained diabetic animals. This magnetic resonance imaging study confirms the prevailing evidence from earlier in vitro and in vivo invasive procedures that exercise training benefits cardiac function in this model of diabetic cardiomyopathy despite the extreme catabolic state of the animals.
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Affiliation(s)
- Rajprasad Loganathan
- Dept. of Physical Therapy and Rehabilitation Science, Univ. of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS 66160, USA
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