In:
Respiration, S. Karger AG, Vol. 92, No. 5 ( 2016), p. 339-347
Kurzfassung:
〈 b 〉 〈 i 〉 Background: 〈 /i 〉 〈 /b 〉 Pulmonary rehabilitation (PR) improves oxidative capacity of peripheral muscles in patients with chronic obstructive pulmonary disease (COPD). The exercise-induced oxidative skeletal muscle adaptation in COPD patients with inherited alpha-1 antitrypsin deficiency (A1ATD) has not been studied. 〈 b 〉 〈 i 〉 Objectives: 〈 /i 〉 〈 /b 〉 To compare PR effects on skeletal muscle adaptation in COPD patients with and without A1ATD. 〈 b 〉 〈 i 〉 Methods: 〈 /i 〉 〈 /b 〉 Nine COPD patients with A1ATD (genotype PiZZ, 6 receiving A1AT augmentation therapy), and 10 ‘usual' COPD patients (genotype PiMM) performed an incremental cycling test and underwent musculus vastus lateralis biopsies before and after a 3-week PR program including exercise training. 〈 b 〉 〈 i 〉 Results: 〈 /i 〉 〈 /b 〉 PiZZ and PiMM patients improved peak work rate following PR (+9 ± 11 W, p 〈 0.05, and +18 ± 9 W, p 〈 0.001, between-group difference p 〈 0.05). PiMM patients increased fibre type I (+8.1%), reduced fibre type IIA (-2.1%) and hybrid fibre type IIA/IIX proportion (-3.9%). Following PR, PiMM patients also raised mitochondrial signalling proteins PGC-1α (4.5-fold), and TFAM (6.4-fold). PiZZ patients had no change in fibre type I but showed a shift of type IIA/IIX (-8.8%) towards fibre type IIA distribution (+8.9%). The capillary to fibre ratio increased by 28% (p 〈 0.05) in PiZZ, whereas no change was observed in PiMM patients. Linear regression analysis revealed that diffusion capacity and A1AT therapy are predictor variables for myofibre type I response to PR (r 〈 sup 〉 2 〈 /sup 〉 = 0.684, p 〈 0.01). 〈 b 〉 〈 i 〉 Conclusions: 〈 /i 〉 〈 /b 〉 Following a 3-week PR with comparable training modalities, PiMM but not PiZZ patients increased the oxidative myofibre type I proportion. This skeletal muscle adaptation pattern suggests better improvement of exercise capacity in PiMM than in PiZZ patients with COPD.
Materialart:
Online-Ressource
ISSN:
0025-7931
,
1423-0356
Sprache:
Englisch
Verlag:
S. Karger AG
Publikationsdatum:
2016
ZDB Id:
1464419-8
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