The relationship between high-fat feeding, insulin resistance, and TNF-alpha gene expression in growing rats

Scope and method of study. The purposes of this study were to examine the effects of high-fat diet on various anthropometric and biochemical parameters, and to elucidate the roles of TNF-alpha in the development of diet-induced insulin resistance. Thirty weanling female Sprague-Dawley rats were randomly assigned to a moderately high-fat soy oil, high-fat soy oil or high-fat tallow diet, and were provided equivalent calories per day, in excess of their requirements for growth and maintenance. After 9 weeks of diet treatment, oral glucose tolerance tests (2 g/kg BW) were performed following an overnight fast. After 10 weeks of diet treatment, body composition analysis was performed by Dual X-Ray Absorptiometry. Liver, muscle, and fat tissues were collected for RNA analysis. Quantitative RT-PCR was used to assess TNF-alpha gene expression in the tissues. Statistical analysis was performed using the general linear model procedure and correlation procedure of SAS. (Abstract shortened by UMI.)...