GLUT4 protein expression in obese and lean 12-month-old rats: insights from different types of data analysis

Autor(es)

P.M. Seraphim ^[1] ; M.T. Nunes ^[2] ; U.F. Machado ^[3]

Afiliação do(s) autor(es)

^[1] Universidade de São Paulo. Instituto de Ciências Biomédicas. Departamento de Fisiologia e Biofísica - Brasil

^[2] Universidade de São Paulo. Instituto de Ciências Biomédicas. Departamento de Fisiologia e Biofísica - Brasil

^[3] Universidade de São Paulo. Instituto de Ciências Biomédicas. Departamento de Fisiologia e Biofísica - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 34, n. 10, p. 1353-1362, 2001-10-00.

Resumo

GLUT4 protein expression in white adipose tissue (WAT) and skeletal muscle (SM) was investigated in 2-month-old, 12-month-old spontaneously obese or 12-month-old calorie-restricted lean Wistar rats, by considering different parameters of analysis, such as tissue and body weight, and total protein yield of the tissue. In WAT, a ~70% decrease was observed in plasma membrane and microsomal GLUT4 protein, expressed as µg protein or g tissue, in both 12-month-old obese and 12-month-old lean rats compared to 2-month-old rats. However, when plasma membrane and microsomal GLUT4 tissue contents were expressed as g body weight, they were the same. In SM, GLUT4 protein content, expressed as µg protein, was similar in 2-month-old and 12-month-old obese rats, whereas it was reduced in 12-month-old obese rats, when expressed as g tissue or g body weight, which may play an important role in insulin resistance. Weight loss did not change the SM GLUT4 content. These results show that altered insulin sensitivity is accompanied by modulation of GLUT4 protein expression. However, the true role of WAT and SM GLUT4 contents in whole-body or tissue insulin sensitivity should be determined considering not only GLUT4 protein expression, but also the strong morphostructural changes in these tissues, which require different types of data analysis. (AU)

• Processo FAPESP: 98/03514-3 - Regulação do transportador de glicose GLUT 4 no diabetes mellitus tipo 2: papel da resistência à insulina
• Beneficiário: Ubiratan Fabres Machado
• Modalidade de apoio: Auxílio à Pesquisa - Temático