Elevated serum Activin A in chronic obstructive pulmonary disease with skeletal muscle wasting

OBJECTIVE: Muscle wasting contributes to the reduced quality of life and increased mortality in chronic obstructive pulmonary disease (COPD). Muscle atrophy in mice with cachexia was caused by Activin A binding to ActRIIB. The role of circulating Activin A leading to muscle atrophy in COPD remains elusive. METHODS: In the present study, we evaluated the relationship between serum levels of Activin A and skeletal muscle wasting in COPD patients. The expression levels of serum Activin A were measured in 78 stable COPD patients and in 60 healthy controls via ELISA, which was also used to determine the expression of circulating TNF-α levels. Total skeletal muscle mass (SMM) was calculated according to a validated formula by age and anthropometric measurements. The fat-free mass index (FFMI) was determined as the fat-free mass (FFM) corrected for body surface area. RESULTS: Compared to the healthy controls, COPD patients had upregulated Activin A expression. The elevated levels of Activin A were correlated with TNF-α expression, while total SMM and FFMI were significantly decreased in COPD patients. Furthermore, serum Activin A expression in COPD patients was negatively associated with both FFMI and BMI. CONCLUSION: The above results showed an association between increased circulating Activin A in COPD patients and the presence of muscle atrophy. Given our previous knowledge, we speculate that Activin A contributes to skeletal muscle wasting in COPD.

Epidemiology of coronary artery bypass grafting at the Hospital Beneficência Portuguesa, São Paulo / Epidemiologia da cirurgia de revascularização miocárdica do Hospital Beneficência Portuguesa de São Paulo

Introduction: The knowledge of the prevalence of risk factors and comorbidities, as well as the evolution and complications in patients undergoing coronary artery bypass graft allows comparison between institutions and evidence of changes in the profile of patients and postoperative evolution over time. Objective: To profile (risk factors and comorbidities) and clinical outcome (complications) in patients undergoing coronary artery bypass graft in a national institution of great surgical volume. Methods: A retrospective cohort study of patients undergoing coronary artery bypass graft in the hospital Beneficência Portuguesa de São Paulo, from July 2009 to July 2010. Results: We included 3,010 patients, mean age of 62.2 years and 69.9% male. 83.8% of patients were hypertensive, 36.6% diabetic, 44.5% had dyslipidemia, 15.3% were smokers, 65.7% were overweight/obese, 29.3% had a family history of coronary heart disease. The expected mortality calculated by logistic EuroSCORE was 2.7%. The isolated CABG occurred in 89.3% and 11.9% surgery was performed without cardiopulmonary bypass. The most common complication was cardiac arrhythmia (18.7%), especially acute atrial fibrillation (14.3%). Pneumonia occurred in 6.2% of patients, acute renal failure in 4.4%, mediastinites in 2.1%, stroke in 1.8% and AMI in 1.2%. The in-hospital mortality was 5.4% and in isolated coronary artery bypass graft was 3.5%. The average hospital stay was 11 days with a median of eight days (3-244 days). Conclusion: The profile of patients undergoing coronary artery bypass graft surgery in this study is similar to other published studies. .

Introdução: O conhecimento da prevalência dos fatores de risco e comorbidades, bem como a evolução com complicações nos pacientes submetidos à cirurgia de revascularização miocárdica, permite a comparação entre instituições e a comprovação de modificações no perfil de pacientes e na evolução pós-operatória ao longo do tempo. Objetivo: Conhecer o perfil (fatores de risco e comorbidades) e a evolução clínica (complicações) nos pacientes submetidos à cirurgia de revascularização miocárdica em uma instituição nacional de grande volume cirúrgico. Métodos: Estudo de coorte retrospectivo de pacientes submetidos ao procedimento de cirurgia de revascularização miocárdica no Hospital Beneficência Portuguesa de São Paulo, no período de julho de 2009 a julho de 2010. Resultados: Foram incluídos 3010 pacientes, com idade média de 62,2 anos e 69,9% do sexo masculino. 82,8% dos pacientes eram hipertensos, 36,6% diabéticos, 44,5% dislipidêmicos, 15,3% tabagistas, 65,7% com sobrepeso/obesidade e 29,3% tinham antecedentes familiares de doença coronária. A mortalidade média esperada calculada pelo EuroSCORE logístico foi de 2,7%. A cirurgia de revascularização miocárdica isolada ocorreu em 89,3% e em 11,9% foi realizada cirurgia sem circulação extracorpórea. A complicação mais comum foi arritmia cardíaca (18,7%), especialmente a fibrilação atrial aguda (14,3%). Pneumonia ocorreu em 6,2% dos pacientes, lesão renal aguda em 4,4%, mediastinite em 2,1%, acidente vascular encefálico em 1,8% e infarto agudo do miocárdio em 1,2%. A mortalidade intra-hospitalar foi de 5,4% e na cirurgia de revascularização miocárdica isolada foi de 3,5%. O tempo de permanência hospitalar médio foi de 11 dias, com mediana de oito dias (3 - 244 dias). Conclusão: O perfil dos pacientes submetidos à cirurgia de revascularização miocárdica neste estudo assemelha-se ao de outros estudos publicados. .

PPM1B and P-IKKβ expression levels correlated inversely with rat gastrocnemius atrophy after denervation

Activated inhibitor of nuclear factor-κB kinase β (IKKβ) is necessary and sufficient for denervated skeletal muscle atrophy. Although several studies have shown that Mg2+/Mn2+-dependent protein phosphatase 1B (PPM1B) inactivated IKKβ, few studies have investigated the role of PPM1B in denervated skeletal muscle. In this study, we aim to explore the expression and significance of PPM1B and phosphorylated IKKβ (P-IKKβ) during atrophy of the denervated gastrocnemius. Thirty young adult female Wistar rats were subjected to right sciatic nerve transection and were sacrificed at 0 (control), 2, 7, 14, and 28 days after denervation surgery. The gastrocnemius was removed from both the denervated and the contralateral limb. The muscle wet weight ratio was calculated as the ratio of the wet weight of the denervated gastrocnemius to that of the contralateral gastrocnemius. RT-PCR and Western blot analysis showed that mRNA and protein levels of PPM1B were significantly lower than those of the control group at different times after the initiation of denervation, while P-IKKβ showed the opposite trends. PPM1B protein expression persistently decreased while P-IKKβ expression persistently increased for 28 days after denervation. PPM1B expression correlated negatively with P-IKKβ expression by the Spearman test, whereas decreasing PPM1B expression correlated positively with the muscle wet weight ratio. The expression levels of PPM1B and P-IKKβ were closely associated with atrophy in skeletal denervated muscle. These results suggest that PPM1B and P-IKKβ could be markers in skeletal muscle atrophy.

Skeletal muscle protein metabolism under denervation atrophy in dog, Canis domesticus.

Denervated dog gastrocnemius muscle has shown a progressive decrease in total protein content, alanine aminotransferase (AIAT), aspartate aminotransferase (AAT) and glutamate dehydrogenase (GDH) activity levels and elevation in free amino acid, ammonia, urea, glutamine contents and AMP deaminase activity levels during post-neurectemic days. The possible implications of these findings are discussed in relation to denervation atrophy.