Molecular basis for the improvement in muscle metaboreflex and mechanoreflex control in exercise-trained humans with chronic heart failure

Abstract

CE. Molecular basis for the improvement in muscle metaboreflex and mechanoreflex control in exercise-trained humans with chronic heart failure. Am J Physiol Heart Circ Physiol 307: H1655-H1666, 2014. First published October 10, 2014 doi:10.1152/ajpheart.00136.2014.-Previous studies have demonstrated that muscle mechanoreflex and metaboreflex controls are altered in heart failure (HF), which seems to be due to changes in cyclooxygenase (COX) pathway and changes in receptors on afferent neurons, including transient receptor potential vanilloid type-1 (TRPV1) and cannabinoid receptor type-1 (CB1). The purpose of the present study was to test the hypotheses: 1) exercise training (ET) alters the muscle metaboreflex and mechanoreflex control of muscle sympathetic nerve activity (MSNA) in HF patients.2) The alteration in metaboreflex control is accompanied by increased expression of TRPV1 and CB1 receptors in skeletal muscle.3) The alteration in mechanoreflex control is accompanied by COX-2 pathway in skeletal muscle. Thirty-four consecutive HF patients with ejection fractions Ͻ40% were randomized to untrained (n ϭ 17; 54 Ϯ 2 yr) or exercise-trained (n ϭ 17; 56 Ϯ 2 yr) groups. MSNA was recorded by microneurography. Mechanoreceptors were activated by passive exercise and metaboreceptors by postexercise circulatory arrest (PECA). COX-2 pathway, TRPV1, and CB1 receptors were measured in muscle biopsies. Following ET, resting MSNA was decreased compared with untrained group. During PECA (metaboreflex), MSNA responses were increased, which was accompanied by the expression of TRPV1 and CB1 receptors. During passive exercise (mechanoreflex), MSNA responses were decreased, which was accompanied by decreased expression of COX-2, prostaglandin-E2 receptor-4, and thromboxane-A2 receptor and by decreased in muscle inflammation, as indicated by increased miRNA-146 levels and the stable NF-B/ IB-␣ ratio. In conclusion, ET alters muscle metaboreflex and mechanoreflex control of MSNA in HF patients. This alteration with ET is accompanied by alteration in TRPV1 and CB1 expression and COX-2 pathway and inflammation in skeletal muscle. heart failure; muscle sympathetic nervous system; metaboreflex; mechanoreflex; exercise training

Sleep-Disordered Breathing Exacerbates Muscle Vasoconstriction and Sympathetic Neural Activation in Patients with Systolic Heart Failure

“…For example, exercise training improves sleep pattern in HF patients with SDB 27 and, in addition, improves endothelial function 48 and remarkably reduces MSNA in chronic HF patients with CSA and OSA. 27,49,50 Similar findings have been reported with continuous positive airway pressure. 21 It remains unknown, but of interest, whether continuous positive airway pressure treatment of these HF patients with SDB will ameliorate their heightened peripheral and central chemoreceptor sensitivity and its adverse neurovascular effects.…”

“…Forty-one patients who fulfilled all the inclusion criteria were enrolled in the study: NoSDB (n=13, 46 [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53] years) and SDB (n=28, 57 [54-61] years). In the SDB group, 6 patients had CSA, and 22 had OSA.…”

Meta-analysis of Exercise Training on Left Ventricular Ejection Fraction in Heart Failure with Reduced Ejection Fraction: A 10-year Update

“…8,9,11,13,14,22–34 The trials included clinically stable older (mean age: 63 years, 77% male, predominantly ischemic etiology) HFrEF patients. Fourteen trials incorporated MICT, 8,9,11,13,23–31,33 four trials compared HIIT with MICT or control, 8,9,11,26 and four trials examined the effects of resistance training performed alone or in combination with aerobic training (resistance training alone, n = 1; combined aerobic and resistance training, n = 3).…”

“…Fourteen trials incorporated MICT, 8,9,11,13,23–31,33 four trials compared HIIT with MICT or control, 8,9,11,26 and four trials examined the effects of resistance training performed alone or in combination with aerobic training (resistance training alone, n = 1; combined aerobic and resistance training, n = 3). 14,22,32,34 The training duration varied between 1 month and 10 years, with most of the trials lasting between 3 and 6 months.…”

Regular physical exercise improves cardiac autonomic and muscle vasodilatory responses to isometric exercise in healthy elderly

“…This result could be justified due to higher sympathetic activity at rest and possibly by an impaired metaboreflex control in the sedentary older adults. It is known that metaboreflex sensitivity is impaired with aging35 and that exercise training improves this sensitivity in cardiovascular diseases such as in heart failure 36. Furthermore, the aging process is associated with impaired baroreflex and chemoreflex sensitivity,37,38 and both are positively modulated by regular aerobic exercise training 39,40.…”