Navegando por Palavras-chave "Myostatin"
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- ItemAcesso aberto (Open Access)Análise da concentração sérica de miostatina e folistatina em pacientes com Dermatomiosite e Polimiosite(Universidade Federal de São Paulo (UNIFESP), 2020-06-26) Maso, Cintia [UNIFESP]; Sato, Emilia Inoue [UNIFESP]; Universidade Federal de São PauloBackground: dermatomyositis (DM) and polymyositis (PM) are systemic autoimmune myopathies (SAM) characterized by chronic inflammation of the skeletal muscle. Myostatin is a protein of the TGF- ß family that negatively regulates muscle mass and the follistatin is an antagonist of myostatin. Objective: to evaluate the serum concentration of myostatin and follistatin in patients with SAM and to evaluate the correlation of these protein with muscle strength, fatigue, functional capacity, damage index, serum creatine kinase and aldolase and body composition index. Methods: cross-sectional study with 50 patients (34 DM and 16 PM) and 52 age-and gender-matched controls. Myostatin and follistatin were measured by ELISA. The patients were evaluated according to the International consensus guidelines for trials of therapies in the idiopathic inflammatory myopathies (IMACS). Fatigue was evaluated through the fatigue severity scale (FSS), quality of life through the Short-Form Health Survey-36 (SF-36), physical activity level trough the International Physical Activity Questionnaire (IPAQ) and body composition was performed by a dual emission densitometer with an X-ray source (Lunar Radiation Corporation, model DPX, Madison, WI, USA). Results: we found no difference in myostatin (14.15±9.65 vs 10.97±6.77; p=0.131) and follistatin (0.53 ±0.71 vs 0.49±0.60; p=0.968) serum concentration between patients with SAM and controls, respectively. When DM, PM and control groups were analyzed separately, we observed higher serum levels of myostatin in the PM group compared to the control group (16.92 ± 12.07 vs. 10.97 ± 6.77 ng / mL; p=0.036). There was no difference in serum myostatin [10.99 (5.94-37.48) vs. 12.48 (1.51 - 35.44); p=0.861] and follistatin levels [0.40 (0.0-0.89) vs. (0.30 (0.0-2.28); p=0.886] among patients with and without low muscle mass by body composition, respectively. Patients without corticosteroids had higher serum levels of myostatin than controls. There was no correlation between myostatin levels with muscle strength, fatigue, functional capacity, damage index, serum creatine kinase and aldolase. There was a weak negative correlation of follistatin with muscle strength, functional capacity (SF-36), lean mass index (LMI) and lean appendicular mass (LAM) and weak positive correlation with HAQ, with no correlation with other studied variables. Conclusion: myostatin and follistatin serum concentration was not different between patients and controls, with higher myostatin serum level in those patients without corticosteroids. There was a weak negative correlation between follistatin and muscle strength, functional capacity (SF-36), lean mass index and a weak positive correlation with HAQ. The dosage of serum myostatin and follistatin did not seem useful to asses disease activity or as markers of treatment response in patients with MAS.
- ItemSomente MetadadadosEffect of kinin B-2 receptor ablation on skeletal muscle development and myostatin gene expression(Churchill Livingstone, 2010-04-01) Souza, K. de Picoli; Batista, E. C. [UNIFESP]; Silva, E. D. [UNIFESP]; Reis, F. C. [UNIFESP]; Silva, S. M. A. [UNIFESP]; Araujo, R. C. [UNIFESP]; Luz, J.; Santos, E. L.; Pesquero, J. B. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Fed Univ Grande DouradosBradykinin (BK) is an active peptide that binds to the kinin B-2 receptor and induces biological events during the development and adult life. in this study we aimed to investigate the effect of kinin B-2 receptor ablation in the postnatal skeletal muscle development and body composition in adult life. for studies of skeletal muscle development, control (C57BI6 - WT) and B-2 receptor knockout mice (B-2(-/-)) were sacrificed at 15, 30 and 90 days after birth, the gastrocnemius skeletal muscle was weighed and myostatin gene expression evaluated by real time PCR. for energy balance determination, data from control and B-2(-/-) at 90 and 120 days were collected by calorimetric method. Body composition at 120 days was determined by chloroform-methanol (total body fat) and Lowry-modified method (total body protein). the results show that B-2(-/-) have significantly increased total body weight at 15, 30 and 90 days of life, when compared to WT. the weight of the gastrocnemius skeletal muscle was also significantly increased at 30 and 90 days of life. Body composition analyses revealed that B-2(-/-) mice exhibit more total corporal protein and less total corporal fat. Energy balance revealed that B-2(-/-) have increased metabolizable energy intake and energy expenditure when compared to control mice, resulting in a lower energy gain. Interestingly, myostatin mRNA expression was significantly decreased in 15 and 30 days old B-2(-/-) mice and after icatibant treatment of WT adult mice for 5 days. in conclusion, together our results show that kinin B-2 receptor deletion increases lean mass, reduces fat mass and improves metabolism efficiency in mice. the mechanism involved in this phenotype could be related to the reduction of myostatin gene expression during postnatal life. (C) 2009 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)Erythropoietin reduces the expression of myostatin in mdx dystrophic mice(Assoc Bras Divulg Cientifica, 2014-11-01) Feder, David; Rugollini, M.; Santomauro, A.; Oliveira, Luciano P.; Lioi, V. P.; Santos, Rosangela Aparecida dos; Ferreira, Leonardo G.; Nunes, Maria Tereza; Carvalho, Maria Helena; Delgado, Pilar O.; Carvalho, Alzira A. S.; Fonseca, Fernando Luiz Affonso [UNIFESP]; Fac Med ABC; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)Erythropoietin (EPO) has been well characterized as a renal glycoprotein hormone regulating red blood cell production by inhibiting apoptosis of erythrocyte progenitors in hematopoietic tissues. EPO exerts regulatory effects in cardiac and skeletal muscles. Duchenne muscular dystrophy is a lethal degenerative disorder of skeletal and cardiac muscle. in this study, we tested the possible therapeutic beneficial effect of recombinant EPO (rhEPO) in dystrophic muscles in mdx mice. Total strength was measured using a force transducer coupled to a computer. Gene expression for myostatin, transforming growth factor-beta 1 (TGF-beta 1), and tumor necrosis factor-alpha (TNF-alpha) was determined by quantitative real time polymerase chain reaction. Myostatin expression was significantly decreased in quadriceps from mdx mice treated with rhEPO (rhEPO = 0.60 +/- 0.11, control= 1.07 +/- 0.11). On the other hand, rhEPO had no significant effect on the expression of TGF-beta 1 (rhEPO = 0.95 +/- 0.14, control= 1.05 +/- 0.16) and TNF-alpha (rhEPO = 0.73 +/- 0.20, control= 1.01 +/- 0.09). These results may help to clarify some of the direct actions of EPO on skeletal muscle.