Expression of subcutaneous adipose tissue phosphoenolpyruvate carboxykinase correlates with body mass index in nondiabetic women.

Phosphoenolpyruvate carboxykinase (PEPCK) is a key enzyme for glyceroneogenesis in adipose tissues. Dysregulated glyceroneogenesis is associated with abnormal fatty acid homeostasis, obesity, and insulin resistance in both animal and cellular studies. However, the role of PEPCK expression in human adipose tissues on metabolic phenotypes has not been explored. This study aimed to analyze the correlation between PEPCK messenger RNA (mRNA) expressions in the subcutaneous adipose tissues with obesity-related metabolic phenotypes. We obtained the demographic data, biochemical variables, and abdominal subcutaneous adipose tissue from 75 nondiabetic nonmenopausal women. The relative PEPCK mRNA levels were quantified by real-time polymerase chain reaction normalized with beta-actin as a control. The PEPCK mRNA levels of subcutaneous tissue were positively correlated with body mass index (BMI) using either univariate (r = 0.413, P < .001) or multivariate linear regression analysis (beta = .978 +/- .239, P < .001). The mRNA expression of PEPCK was also positively correlated with body fat percentage (r = 0.436, P < .001), plasma triacylglycerol, and total cholesterol levels (both P values < .001). However, the significant correlation between lipid profile and PEPCK expression in subcutaneous tissue was abolished after adjusting for BMI. The relative subcutaneous PEPCK mRNA level was not correlated with fasting plasma glucose and insulin, and with an insulin resistance index measured with homeostasis model assessment. In conclusion, we showed that PEPCK mRNA expression in the subcutaneous adipose tissues was associated with BMI and plasma triacylglycerol and total cholesterol levels, but was not correlated with insulin resistance index.