scholarly journals Exercise training improves systolic function in hypertensive myocardium

2011 ◽  
Vol 111 (6) ◽  
pp. 1637-1643 ◽  
Author(s):  
Joseph R. Libonati ◽  
Abdelkarim Sabri ◽  
Canhua Xiao ◽  
Scott M. MacDonnell ◽  
Brian F. Renna

The general purpose of this study was to test the effect of exercise training on the left ventricular (LV) pressure-volume relationship (LV/PV) and apoptotic signaling markers in normotensive and hypertensive hearts. Four-month-old female normotensive Wistar-Kyoto rats (WKY; n = 37) and spontaneously hypertensive rats (SHR; n = 38) were assigned to a sedentary (WKY-SED, n = 21; SHR-SED, n = 19) or treadmill-trained (WKY-TRD, n = 16; SHR-TRD, n = 19) group (∼60% V̇o2 peak, 60 min/day, 5 days/wk, 12 wk). Ex vivo LV/PV were established in isovolumic Langendorff-perfused hearts, and LV levels of Akt, phosphorylated Akt (AktPi), Bad, phosphorylated Bad (BadPi) c-IAP, x-IAP, calcineurin, and caspases 3, 8, and 9 were measured. Heart-to-body weight ratio was increased in SHR vs. WKY ( P < 0.05), concomitant with increased calcineurin mRNA ( P < 0.05). There was a rightward shift in the LV/PV ( P < 0.05) and a reduction in systolic elastance (Es) in SHR vs. WKY. Exercise training corrected Es in SHR ( P < 0.05) but had no effect on the LV/PV in WKY. Caspase 3 was increased in SHR-SED relative to WKY-SED, while BadPi, c-IAP, and x-IAP were significantly lower in SHR relative to WKY ( P < 0.05). Exercise training increased BadPi in both WKY and SHR but did not alter caspase 9 activity in either group. While caspase 3 activity was increased with training in WKY ( P < 0.05), it was unchanged with training in SHR. We conclude that moderate levels of regular aerobic exercise attenuate systolic dysfunction early in the compensatory phase of hypertrophy, and that a differential phenotypical response to moderate-intensity exercise exists between WKY and SHR.

2019 ◽  
Vol 40 (14) ◽  
pp. 909-920 ◽  
Author(s):  
Zahra Samadian ◽  
Javad Tolouei Azar ◽  
Sana Moshari ◽  
Mazdak Razi ◽  
Asghar Tofighi

AbstractThe aim of this study was to investigate the ameliorative effect of moderate-intensity exercise training in sole and simultaneous forms with insulin on experimental type 1 diabetes (T1D)-induced apoptosis. A total of 36 mature male Wistar rats were divided into six equally sized groups, including sedentary control (Con), moderate-intensity exercise training (E-sole), sedentary T1D-induced (D-sole), moderate-exercise-trained T1D-induced (DE), insulin-treated sedentary T1D-induced (DI) and exercise-trained, and insulin-treated T1D-induced (DEI) groups. The 6-week exercise training intervention was involved 30 min of moderate-intensity running on a treadmill once daily (5 days/week). Next, tubular differentiation (TDI) and spermiogenesis (SPI) indices were assessed. The Bcl-2, Bax and caspase-3 expressions were determined using RT-PCR, immunohistochemistry and western blot techniques. Finally, the TUNEL staining was used to analyze the apoptosis ratio. The moderate-intensity exercise training in the sole and when simultaneously considered with insulin (DEI) maintained testicular cellularity, up-regulated Bcl-2 expression, reduced Bax expression and ameliorated the diabetes-induced apoptosis. We failed to show remarkable alterations in caspase-3 mRNA and protein levels in the DE group versus D-sole animals. In conclusion, the moderate-intensity exercise training is able to potentially protect testicular cells from T1D-induced intrinsic apoptosis via up-regulating Bcl-2 and downregulating Bax expressions. Moreover, it amplifies the insulin-induced anti-apoptotic impacts.


2007 ◽  
Vol 103 (1) ◽  
pp. 353-358 ◽  
Author(s):  
Brian F. Renna ◽  
Scott M. MacDonnell ◽  
Patricia O. Reger ◽  
Deborah L. Crabbe ◽  
Steven R. Houser ◽  
...  

Hypertension and exercise independently induce left ventricular (LV) remodeling and alter LV function. The purpose of this study was to determine systolic and diastolic LV pressure-volume relationships (LV-PV) in spontaneously hypertensive rats (SHR) with and without LV hypertrophy, and to determine whether 6 mo of exercise training modified the LV-PV in SHR. Four-month-old female SHR ( n = 20), were assigned to a sedentary (SHR-SED) or treadmill-trained (SHR-TRD) group (∼60% peak O2 consumption, 5 days/wk, 6 mo), while age-matched female Wistar-Kyoto rats (WKY; n = 13) served as normotensive controls. The LV-PV was determined using a Langendorff isolated heart preparation at 4 (no hypertrophy: WKY, n = 5; SHR, n = 5) and 10 mo of age (hypertrophy: WKY, n = 8; SHR-SED, n = 8; SHR-TRD, n = 7). At 4 mo, the LV-PV in SHR was similar to that observed in WKY controls. However, at 10 mo of age, a rightward shift in the LV-PV occurred in SHR. Exercise training did not alter the extent of the shift in the LV-PV relative to SHR-SED. Relative systolic function, i.e., relative systolic elastance, was ∼50% lower in SHR than WKY at 10 mo of age ( P < 0.05). Doppler-derived LV filling parameters [early wave (E), atrial wave (A), and the E/A ratio] were similar between groups. LV capacitance was increased in SHR at 10 mo ( P < 0.05), whereas LV diastolic chamber stiffness was similar between groups at 10 mo. Hypertrophic remodeling at 10 mo of age in female SHR is manifest with relative systolic decompensation and normal LV diastolic function. Exercise training did not alter the LV-PV in SHR.


2000 ◽  
Vol 279 (1) ◽  
pp. H210-H215 ◽  
Author(s):  
Kirk T. Spencer ◽  
Keith Collins ◽  
Claudia Korcarz ◽  
Richard Fentzke ◽  
Roberto M. Lang ◽  
...  

Dilated cardiomyopathy (DC) is a leading cause of cardiovascular morbidity, and nonpharmacological therapies, such as exercise training, have been suggested. The effects of exercise on left ventricular (LV) function and mortality remain controversial. Using a recently described murine model of DC, which involves a dominant-negative form of the cAMP response element binding protein (CREB) transcription factor (CREBA133) under the control of the cardiac myocyte-specific α-myosin heavy chain promoter, we sought to assess the effects of moderate-intensity exercise training on LV performance and mortality. Thirty-two transgenic mice were subjected to exercise training and compared with sedentary controls. There was progressive enlargement in LV dimensions in both the sedentary and exercise-trained mice. LV performance was progressively impaired, and exercise training did not prevent this decline. The sedentary CREBA133 mice displayed a significantly increased rate of death, and exercise training did not prevent or delay this excess mortality. The CREBA133 murine model of inherited DC demonstrated progressive ventricular dilatation and dysfunction with increased mortality, which was not altered with 12 wk of moderate-intensity exercise training.


1993 ◽  
Vol 265 (6) ◽  
pp. H2094-H2098 ◽  
Author(s):  
S. K. Powers ◽  
D. Criswell ◽  
J. Lawler ◽  
D. Martin ◽  
F. K. Lieu ◽  
...  

Controversy exists as to the effect of endurance training on myocardial antioxidant enzyme activity. These experiments sought to clarify this issue by examining antioxidant enzyme activities in the rat ventricular myocardium in response to different intensities and durations of exercise training. Female Fischer-344 rats (120 days old) were assigned to either a sedentary control group or one of nine exercise training groups. Animals were exercised on a motorized treadmill for 10 wk; combinations of three durations (30, 60, and 90 min/day), and three levels of exercise intensity (low, moderate, and high) were studied. Exercise training did not alter (P > 0.05) citrate synthase, catalase, or glutathione peroxidase activities in the right or left ventricle. In contrast, high-intensity exercise (all durations) and moderate-intensity exercise (90 min/day) resulted in a significant increase (P < 0.05; +28–30%) in right ventricular superoxide dismutase (SOD) activity. Similarly, high-intensity exercise training (all durations) resulted in a significant elevation (P < 0.05; +14-26%) of left ventricular SOD activity. Furthermore, low- and moderate-intensity exercise training of long duration (i.e., 60–90 min/day) resulted in significant increases (P < 0.05; +10-23%) in left ventricular SOD activity. These data support the hypothesis that high-intensity exercise (> or = 30 min/day) or moderate-intensity exercise of long duration (> or = 60 min/day) is effective in upregulating SOD activity in the ventricular myocardium.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C Borrelli ◽  
P Sciarrone ◽  
F Gentile ◽  
N Ghionzoli ◽  
G Mirizzi ◽  
...  

Abstract Background Central apneas (CA) and obstructive apneas (OA) are highly prevalent in heart failure (HF) both with reduced and preserved systolic function. However, a comprehensive evaluation of apnea prevalence across HF according to ejection fraction (i.e HF with patients with reduced, mid-range and preserved ejection fraction- HFrEf, HFmrEF and HFpEF, respectively) throughout the 24 hours has never been done before. Materials and methods 700 HF patients were prospectively enrolled and then divided according to left ventricular EF (408 HFrEF, 117 HFmrEF, 175 HFpEF). All patients underwent a thorough evaluation including: 2D echocardiography; 24-h Holter-ECG monitoring; cardiopulmonary exercise testing; neuro-hormonal assessment and 24-h cardiorespiratory monitoring. Results In the whole population, prevalence of normal breathing (NB), CA and OA at daytime was 40%, 51%, and 9%, respectively, while at nighttime 15%, 55%, and 30%, respectively. When stratified according to left ventricular EF, CA prevalence decreased from HFrEF to HFmrEF and HFpEF: (daytime CA: 57% vs. 43% vs. 42%, respectively, p=0.001; nighttime CA: 66% vs. 48% vs. 34%, respectively, p&lt;0.0001), while OA prevalence increased (daytime OA: 5% vs. 8% vs. 18%, respectively, p&lt;0.0001; nighttime OA: 20 vs. 29 vs. 53%, respectively, p&lt;0.0001). When assessing moderte-severe apneas, defined with an apnea/hypopnea index &gt;15 events/hour, prevalence of CA was again higher in HFrEF than HFmrEF and HFpEF both at daytime (daytime moderate-severe CA: 28% vs. 19% and 23%, respectively, p&lt;0.05) and at nighttime (nighttime moderate-severe CA: 50% vs. 39% and 28%, respectively, p&lt;0.05). Conversely, moderate-severe OA decreased from HFrEF to HFmrEF to HFpEF both at daytime (daytime moderate-severe OA: 1% vs. 3% and 8%, respectively, p&lt;0.05) and nighttime (noghttime moderate-severe OA: 10% vs. 11% and 30%, respectively, p&lt;0.05). Conclusions Daytime and nighttime apneas, both central and obstructive in nature, are highly prevalent in HF regardless of EF. Across the whole spectrum of HF, CA prevalence increases and OA decreases as left ventricular systolic dysfunction progresses, both during daytime and nighttime. Funding Acknowledgement Type of funding source: None


2011 ◽  
Vol 43 (Suppl 1) ◽  
pp. 22
Author(s):  
Jason R. Jaggers ◽  
Wesley D. Dudgeon ◽  
Kenneth D. Phillips ◽  
Stephanie Burgess ◽  
J. Larry Durstine ◽  
...  

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Sayed Tariq ◽  
James Anderson ◽  
Rohit Dhingra ◽  
Mikhail Torosoff

Background: Effects of anti-hypertensive medications on left ventricular dimensions and systolic function in patients with arterio-venous (AV) fistulas have not been well investigated. Material and Methods: Medical charts and echocardiograms of 346 patients with AV fistula were reviewed. Of 346, 149 patients had TTE prior to the AV fistula surgery, 197 had TTE after the AV fistula surgery, and 76 patients had TTE before and after the AV fistula surgery. Data on medication use was available in 314 patients. ANOVA, chi-square, and logistic regression tests were employed. Results: In patients scheduled for AV fistula placement, 20% (31/149) patients had systolic dysfunction and 15% (22/142) had increased LV end-diastolic dimensions (LVEDD). Moderate systolic LV dysfunction was observed in 6% (9/149) and additional 8% (12/149) had severe LV dysfunction. Increased LVEDD with some LV dysfunction was noted in 27% (38/142).Following the AV fistula placement, 18% (36/197) of patients had systolic dysfunction and 12% (22/187) had increased LV end-diastolic dimensions (LVEDD). Moderate or severe systolic LV dysfunction was observed in 6% (5/197). LV systolic dysfunction or dilatation was noted in 23% (43/187). Of 314 patients, 63% were on beta-blockers (BB), 25% were on ACE inhibitor or an ARB , 43% on calcium-channel blocker , and 15% on alpha-antagonist . BB, ACEi-ARB, or AA were not associated with increased LVEDD or systolic dysfunction before or after the AV fistula placement. Prior to AV fistula, CCB treatment was not related to LV dilatation (36% in each group, p=0.981) Post AV fistula, CCB treatment was associated with increased LV dimensions (71% vs. 46%, p=0.029) but not LV systolic dysfunction (49% in LV dysfunction vs. 38% in the rest, p=0.446) . This association persisted after adjustment for co-morbidities and demographic parameters. Conclusions: LV systolic dysfunction and/or dilatation are common in patients undergoing AV fistula surgery. Despite decreased use of Ca-channel blockers in patients with LV dysfunction prior to AV fistula, Ca-channel blockers are associated with increased LV dimensions post AV fistula, and probably should be avoided in this vulnerable patient population.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Rebecca H Ritchie ◽  
Nga Cao ◽  
Yung George Wong ◽  
Sarah Rosli ◽  
Helen Kiriazis ◽  
...  

Nitroxyl (HNO), a redox congener of NO•, is a novel regulator of cardiovascular function combining vasodilator and positive inotropic properties. Our previous studies have demonstrated these properties occur concomitantly in the intact heart; HNO moreover also exhibits antihypertrophic and superoxide-suppressing actions. HNO donors may thus offer favorable actions in heart failure. The impact of chronic HNO donor administration has however yet to be reported in this context. We tested the hypothesis that the HNO donor 1-nitrosocyclohexyl acetate (1-NCA) limits cardiomyocyte hypertrophy and left ventricular (LV) diastolic dysfunction in a mouse model of diabetic cardiomyopathy in vivo. Male 6 week-old FVB/N mice received either streptozotocin (55 mg/kg/day i.p. for 5 days, n=17), to induce type 1 diabetes, or citrate vehicle (n=16). After 4 weeks of hyperglycemia, mice were allocated to 1-NCA therapy (83mg/kg/day i.p.) or vehicle, and followed for a further 4 weeks. As shown in the table, blood glucose was unaffected by 1-NCA. LV diastolic dysfunction was evident in diabetic mice, measured as echocardiography-derived A wave velocity, deceleration time and E:A ratio; LV systolic function was preserved. Diabetes-induced diastolic dysfunction was accompanied by increased LV cardiomyocyte size, hypertrophic and pro-fibrotic gene expression, and upregulation of LV superoxide. These characteristics of diabetic cardiomyopathy were largely prevented by 1-NCA treatment. Selectivity of 1-NCA as a donor of HNO versus NO• was demonstrated by the sensitivity of the coronary vasodilation response of 1-NCA to the HNO scavenger L-cysteine (4mM), but not to the NO• scavenger hydroxocobalamin (50μM), in the normal rat heart ex vivo (n=3-7). Collectively, our studies provide the first evidence that HNO donors may represent a promising new strategy for the treatment of diabetic cardiomyopathy, and implies their therapeutic efficacy in settings of chronic heart failure.


2011 ◽  
Vol 51 (2) ◽  
pp. 79
Author(s):  
Erlina Masniari Napitupulu ◽  
Fera Wahyuni ◽  
Tina Christina L. Tobing ◽  
Muhammad Ali ◽  
Bidasari Lubis

Background Chronic severe anemia is a connnon disease. Cardiac output may increase when the hemoglobin (Hb) level decreases to < 7 g/dL for 3 months or more. Alteration of left ventricular (LV) function occurs frequently in children 'With chronic severe anemia, in the {onn of concentric LV hypertrophy, LV dilatation with or v.ithout LV hypertrophy, or systolic dysfunction. Objective To examine the correlation between Hb level and alteration of LV systolic function in children with chronic severe anemia. Methods We conducted a cross-sectional study in Adam Malik Hospital from October to December 2009. Subjects were chronic severely anemic children. Left ventricular systolic function (ejection fraction/EF, fractional shortening/FS) and dimensions (left ventricular end diastolic diameter/LVEDD and left ventricular end systolic diameter/LVESD) were measured using Hitachi EUB 5500 echocardiography unit. Univariate analysis  and Pearson correlation were performed.Results Thirty children were enrolled in the study. The mean of age was 113.5 months (SD 53.24). Hb values ranged from 2.1 to 6.9 g/dL with mean value of 4.6 g/dL (SD 1.44). Mean duration of anemia was 3.9 months (SD 0.70). Chronic severe anemia was not associated \\lith decreased LV systolic function [EF 62.2% (SD 9.16), r =0.296, P=0.112; FS 33.8% (SD 7.26), r =0.115, P=0.545], nor LV dimension changes [LVEDD 40.2 mm (SD 6.85), r = -0.192, P=0.308; LVESD 26.2 mm (SD 4.98), r=-0.266, P=0.156]. Conclusion There was no correlation between Hb level in chronically anemic children and changes in LV systolic function or dimension.


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