Lung injury-dependent oxidative status and chymotrypsin-like activity of skeletal muscles in hamsters with experimental emphysema

Abstract

BackgroundPeripheral skeletal muscle is altered in patients suffering from emphysema and chronic obstructive pulmonary disease (COPD). Oxidative stress have been demonstrated to participate on skeletal muscle loss of several states, including disuse atrophy, mechanical ventilation, and chronic diseases. No evidences have demonstrated the occurance in a severity manner.MethodsWe evaluated body weight, muscle loss, oxidative stress, and chymotrypsin-like proteolytic activity in the gastrocnemius muscle of emphysemic hamsters. The experimental animals had 2 different severities of lung damage from experimental emphysema induced by 20 mg/mL (E20) and 40 mg/mL (E40) papain.ResultsThe severity of emphysema increased significantly in E20 (60.52 ± 2.8, p < 0.05) and E40 (52.27 ± 4.7; crossed the alveolar intercepts) groups. As compared to the control group, there was a reduction on body (171.6 ± 15.9 g) and muscle weight (251.87 ± 24.87 mg) in the E20 group (157.5 ± 10.3 mg and 230.12 ± 23.52 mg, for body and muscle weight, respectively), which was accentuated in the E40 group (137.4 ± 7.2 g and 197.87 ± 10.49 mg, for body and muscle weight, respectively). Additionally, the thiobarbituric acid reactive substances (TBARS), tert-butyl hydroperoxide-initiated chemiluminescence (CL), carbonylated proteins, and chymotrypsin-like proteolytic activity were elevated in the E40 group as compared to the E20 group (p < 0.05 for all comparisons). The severity of emphysema significantly correlated with the progressive increase in CL (r = −0.95), TBARS (r = −0.98), carbonyl proteins (r = −0.99), and chymotrypsin-like proteolytic activity (r = −0.90). Furthermore, augmentation of proteolytic activity correlated significantly with CL (r = 0.97), TBARS (r = 0.96), and carbonyl proteins (r = 0.91).ConclusionsTaken together, the results of the present study suggest that muscle atrophy observed in this model of emphysema is mediated by increased muscle chymotrypsin-like activity, with possible involvement of oxidative stress in a severity-dependent manner.

Protective effect of edaravone for tourniquet-induced ischemia-reperfusion injury on skeletal muscle in murine hindlimb

“…Re-establishment of blood flow is essential to salvage ischemic tissues; however reperfusion itself causes further damage to the ischemic tissue, threatening function and viability of the organ. I/R injuries occur in a wide range of organs including the heart, kidney, liver, brain and intestines heart, liver, brain, kidney, colon and skeletal muscles [2-4,31]. Examples of I/R injuries of skeletal muscles in this study can arise as a consequence of a range of vascular events including thrombolytic therapy, organ transplantation, limb trauma, or aortic clamping during repair of abdominal aortic aneurysms.…”

“…Reperfusion triggers a cascade of acute inflammatory events, leading to cellular death and resulting in tissue dysfunction and necrosis [1]. Most research concerning I/R injury has focused on the heart, kidney, liver, brain, lung and intestines since these tissues are considered vital organs [2-4]. I/R injury to skeletal muscles is also a serious problem however, and can cause local disturbances as well as systemic problems such as crush syndrome due to leakage from muscle cells into circulating blood.…”

Oxidative and proteolytic profiles of the right and left heart in a model of cancer-induced cardiac cachexia

“…It is well known that elevated metabolic rates increase O 2 consumption by the mitochondria in muscle tissues and, consequently, the generation of ROS by mitochondria in the form of superoxide anions. At the same time, adaptive mechanisms appear to decrease oxidative stress by increasing the production and/or mobilization of antioxidants, reducing the production of oxidants, and/or reducing radical leakage during oxidative phosphorylation [38]. Thus, it is reasonable to infer that the differences between the sides of the heart, especially with respect to the increased in the overall height of CL curves obtained in the LH on the 5th day and the decreased CL curve in the RH on the 10th day after tumour implantation, may be due to different responses to different metabolic activities, indicating that the two sides of heart function independently from each other.…”

Oxidative and proteolysis‐related parameters of skeletal muscle from hamsters with experimental pulmonary emphysema: a comparison between papain and elastase induction

“…), saline (0.3 ml/100 g body weight; control + saline [CS] group); papain (40 mg/100 g body weight in 0.3 ml normal saline) emphysema with papain [EP] group) (Tonon et al . ) or porcine elastase (5.2 IU/100 g body weight [Alfa Aesar, Shrewsbury, MA, USA] in 0.3 mL normal saline) emphysema with porcine elastase [EE] group) (Hayes et al . ) were instilled intratracheally through a 27‐gauge hypodermic needle, according to the procedure described by Mattson et al .…”

“…In addition, Tonon et al . () demonstrated that muscle atrophy, observed in a model of 60 days of emphysema induced by papain instillation (40 mg/ml) in rats, is mediated by increased muscle proteolysis, with involvement of oxidative stress.…”