Abstract
Skeletal muscle capillarization and angiogenesis impairments have been shown in COPD, and may limit the benefit of exercise training (Gouzi et al, 2013 Eur Respir J). The capillary maturation, strongly linked to angiogenesis, could also be impaired. The aim of this study was to investigate the skeletal muscle angiogenesis and the capillary maturation in response to exercise training in COPD.
Seven control subjects were compared to 14 matched COPD patients (FEV1: 75 ± 19 % pred) trained at an intensity matched on relative (%V’O2, RI group) or absolute (ml/min/kg, AI group) level of the training intensity of controls. Capillarization indexes (capillary-to-fiber ratio (C/F); capillary to fiber perimeter exchange index (CFPE)), pericyte coverage (pericyte area-to-capillary area ratio (PcA/CA)) and skeletal muscle mRNA expression of angiogenic factors were assessed on vastus lateralis muscle biopsies, before and after 5 and 10 weeks of exercise training.
Controls showed better quadriceps endurance benefits compared to both AI and RI (Time*Group interaction: p<0.05). Despite lower baseline CFPE in COPD groups (AI: p<0.03; RI: p=0.053), the 3 groups increased similarly C/F ratio (Time effect: p<0.01). However, the capillary maturation index (PcA/CA) was lower in both COPD groups, regardless of the training time (Group effect: p<0.001). At week 5, the pro- to anti-angiogenic/maturation factor ratios (VEGF-A/TSP-1; Ang1/Ang2) were also lower in the AI group (p<0.05 each).
Our study is the first to show a defective maturation during the muscle angiogenesis in COPD in response to exercise training, involving pericyte impairment, as previously reported in other chronic diseases.
Footnotes
Cite this article as: European Respiratory Journal 2018 52: Suppl. 62, OA1621.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2018