TY - JOUR
T1 - Role of the fatty acid binding protein mal1 in obesity and insulin resistance
AU - Maeda, Kazuhisa
AU - Uysal, K. Teoman
AU - Makowski, Liza
AU - Görgün, Cem Z.
AU - Atsumi, Genichi
AU - Parker, Rex A.
AU - Brüning, Jens
AU - Hertzel, Ann Vogel
AU - Bernlohr, David A.
AU - Hotamisligil, Gökhan S.
PY - 2003/2/1
Y1 - 2003/2/1
N2 - The metabolic syndrome is a cluster of metabolic and inflammatory abnormalities including obesity, insulin resistance, type 2 diabetes, hypertension, dyslipidemia, and atherosclerosis. The fatty acid binding proteins aP2 (fatty acid big protein [FABP]-4) and mal1 (FABP5) are closely related and both are expressed in adipocytes. Previous studies in aP2-deficient mice have indicated a significant role for aP2 in obesity-related insulin resistance, type 2 diabetes, and atherosclerosis. However, the biological functions of mal1 are not known. Here, we report the generation of mice with targeted null mutations in the mal1 gene as well as transgenic mice overexpressing mal1 from the aP2 promoter/enhancer to address the role of this FABP in metabolic regulation in the presence or absence of obesity. To address the role of the second adipocyte FABP in metabolic regulation in the presence and deficiency of obesity, absence of mal1 resulted in increased systemic insulin sensitivity in two models of obesity and insulin resistance. Adipocytes isolated from mal1-deficient mice also exhibited enhanced insulin-stimulated glucose transport capacity. In contrast, mice expressing high levels of mal1 in adipose tissue display reduced systemic insulin sensitivity. Hence, our results demonstrate that mal1 modulates adipose tissue function and contributes to systemic glucose metabolism and constitutes a potential therapeutic target in insulin resistance.
AB - The metabolic syndrome is a cluster of metabolic and inflammatory abnormalities including obesity, insulin resistance, type 2 diabetes, hypertension, dyslipidemia, and atherosclerosis. The fatty acid binding proteins aP2 (fatty acid big protein [FABP]-4) and mal1 (FABP5) are closely related and both are expressed in adipocytes. Previous studies in aP2-deficient mice have indicated a significant role for aP2 in obesity-related insulin resistance, type 2 diabetes, and atherosclerosis. However, the biological functions of mal1 are not known. Here, we report the generation of mice with targeted null mutations in the mal1 gene as well as transgenic mice overexpressing mal1 from the aP2 promoter/enhancer to address the role of this FABP in metabolic regulation in the presence or absence of obesity. To address the role of the second adipocyte FABP in metabolic regulation in the presence and deficiency of obesity, absence of mal1 resulted in increased systemic insulin sensitivity in two models of obesity and insulin resistance. Adipocytes isolated from mal1-deficient mice also exhibited enhanced insulin-stimulated glucose transport capacity. In contrast, mice expressing high levels of mal1 in adipose tissue display reduced systemic insulin sensitivity. Hence, our results demonstrate that mal1 modulates adipose tissue function and contributes to systemic glucose metabolism and constitutes a potential therapeutic target in insulin resistance.
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U2 - 10.2337/diabetes.52.2.300
DO - 10.2337/diabetes.52.2.300
M3 - Article
C2 - 12540600
AN - SCOPUS:0037315168
SN - 0012-1797
VL - 52
SP - 300
EP - 307
JO - Diabetes
JF - Diabetes
IS - 2
ER -