PMC

Ubiquitin–protein conjugation in diaphragm muscle homogenates of patients with COPD (n = 7) compared with the patients without COPD (n = 5). (A) Total optical density of ubiquitin–protein conjugates in diaphragm muscle homogenates. Data are presented as mean ± SEM. *p < 0.05 difference from group without COPD. (B) Antiubiquitin immunoblot of diaphragm muscle homogenates from patients with and without COPD. Each lane shows result for a diaphragm muscle homogenate from one patient. Molecular weight markers are shown in kilodaltons. Note the appearance of additional ubiquitin-protein conjugates with molecular masses between approximately 75 and 250 kD in diaphragm muscle homogenates from patients with COPD. Also, optical density of ubiquitin–protein conjugates with molecular masses of approximately 30 and approximately 70 kD, present in diaphragm muscle homogenates from patients without COPD, was increased in diaphragm muscle homogenates from patients with COPD.

a Mean values and standard deviation of myogenin, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. b Mean values and standard deviation of PPAR-α, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant, *p ≤ 0.05 and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. c Mean values and standard deviation of PPAR-gamma, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: *p ≤ 0.05 and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. d Mean values and standard deviation of PGC-1α, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant between any of the intervention groups (U and E–U) and control mice. a.u. arbitrary units, E–U elastase–urethane, OD optical densities, PPAR- peroxisome proliferator-activated receptor alpha; PPAR- peroxisome proliferator-activated receptor gamma, PGC-1 peroxisome proliferator-activated receptor gamma coactivator-1α, U urethane

a Mean values and standard deviation of MDA, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: (i) n.s.: non-significant and **p ≤ 0.01 between any of the intervention groups (U and E–U) and control mice. b Mean values and standard deviation of SOD1, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. c Mean values and standard deviation of SOD2, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant, **p ≤ 0.01 and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. d Mean values and standard deviation of catalase, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. a.u. arbitrary units, E–U elastase–urethane, MDA malondialdehyde, OD optical densities, SOD1 superoxide dismutase isoform 1, SOD2 superoxide dismutase isoform 2, U urethane

a Mean values and standard deviation of skeletal muscle actin, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. b Mean values and standard deviation of MyHC, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant, **p ≤ 0.01, and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. c Mean values and standard deviation of creatine kinase (CK), in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: *p ≤ 0.05 and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. d Mean values and standard deviation of carbonic anhydrase-3, in diaphragm (white bars) and gastrocnemius (black bars) muscles as measured by optical densities. Statistical significance is represented as follows: n.s.: non-significant and ***p ≤ 0.001 between any of the intervention groups (U and E–U) and control mice. a.u. arbitrary units, E–U elastase–urethane, MyHC myosin heavy chain, OD optical densities, U urethane