Resistive Training and Molecular Regulators of Vascular-Metabolic Risk in Chronic Stroke

Abstract

Background Proliferator activator receptor (PPAR)-γ coactivator (PGC-1α) gene and Sirtuin-1 (SIRT1) respond to physiological stimuli and regulate insulin resistance. Inflammatory markers TNF-α, interleukin-6, C-reactive protein (CRP) and the soluble forms of intracellular adhesion molecule (sICAM-1) and vascular CAM-1 (sVCAM-1) are associated with increased risk of diabetes and coronary heart disease. Resistive training reduces hyperinsulinemia and improves insulin action in chronic stroke. Yet, the molecular mechanisms for this are unknown. This study will determine the effects of RT on skeletal muscle PGC-1α and Sirtuin-1 (SIRT1) mRNA expression and inflammatory and vascular markers. Methods Stroke survivors (50–76 years) underwent a fasting blood draw for measurement of TNF-α, IL-6, CRP, serum amyloid A, sICAM-1, sVCAM-1 and bilateral vastus lateralis biopsies before and after RT. Participants were also assessed using bilateral multi-slice thigh CT scans from the knee to the hip, a total body scan by DXA, and one-repetition (1-RM) strength testing. Subjects performed two sets of three lower extremity RT exercises 3x/week for 12-weeks. Results Bilateral leg press and leg extension strength increased ~30–50% with RT (P<0.001). Body weight, total body fat mass, and fat-free mass did not change. Thigh muscle area and volume increased in both legs (P<0.05). Non-paretic muscle PGC-1α mRNA expression increased 14% (P<0.05) after RT and SIRT1 mRNA decreased 24% (P<0.05) and 31% (P<0.01) in paretic and non-paretic muscle. There were no significant changes in plasma inflammation with training. Discussion RT in chronic stroke induces changes in key skeletal muscle regulators of metabolism, without effecting circulating inflammation.

Aerobic With Resistance Training or Aerobic Training Alone Poststroke: A Secondary Analysis From a Randomized Clinical Trial

“…Three single-group studies that included RT interventions alone (n = 10 to 18 participants) did not result in a change in total body lean mass likely owing to an insufficient total body stimulus (2 sets of 3 lower-extremity exercises). 57-59 Furthermore, an earlier study conducted by our group failed to demonstrate a significant increase in total body lean mass by DXA in 41 poststroke participants after 6 months of AT+RT. 47 Similar to the current study, the RT program targeted all major muscle groups (1 to 2 sets of 10 to 11 exercises) and was progressed by a combination of increasing repetitions and weight load.…”

Effect of Community Exercise for Patients with Stroke: A Systematic Review and Meta-analysis

“…No participants experienced any adverse events in the included RCTs. 100.0 % 119 117 Total (95 % CI) Heterogeneity: Tau 2 = 0.00; Chi 2 = 0.74, df = 3 (P = 0.86); I 2 = 0 % Test for overall effect: Z = 3.65 (P = 0.0003) 100.0 % 88 85 Total (95 % CI) Heterogeneity: Tau 2 = 0.00; Chi 2 = 0.83, df = 2 (P = 0.66); I 2 = 0 % Test for overall effect: Z = 2.60 (P = 0.009) Community-based exercise therapy was reported to be a feasible method of modifying metabolic risk factors [29,30]. A 23 % increase (0.3 mmol/L) of high-density lipoprotein cholesterol (HDL-C) was revealed after exercise.…”

The Neuroprotective Effect of Irisin in Ischemic Stroke

“…Moreover, the patterns of exercise are very important for the generation of irisin. The forms of exercise include endurance and resistance exercise training; the former is an aerobic and cardiovascular form of exercise, while the latter focuses more on muscle strength and hypertrophy (Cornelissen and Smart, 2013 ; Ryan et al, 2017 ). At present, evidence suggests that irisin is involved in endurance exercise.…”

“…Physical exercise can reportedly alleviate some of these pathophysiological processes. In addition, in the rehabilitation stage of stroke, exercise can also effectively improve sequelae symptoms (Li et al, 2017 ; Ryan et al, 2017 ). In 2013, studies reported that brain-derived neurotrophic factor (BDNF) is a possible mediator of the neurological benefits of exercise (Mang et al, 2013 ).…”