Chang Tien-Jyun, Lee Wei-Jei, Chang Hui-Min, Lee Kuan-Ching, Chuang Lee-Ming
Division of Endocrinology and Metabolism, Department of Internal Medicine, National Taiwan University Hospital, Taipei 10002, Taiwan.
Metabolism. 2008 Mar;57(3):367-72. doi: 10.1016/j.metabol.2007.10.012.
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.
磷酸烯醇式丙酮酸羧激酶（PEPCK）是脂肪组织中甘油生成的关键酶。在动物和细胞研究中，甘油生成失调与脂肪酸稳态异常、肥胖及胰岛素抵抗相关。然而，PEPCK在人类脂肪组织中的表达对代谢表型的作用尚未得到研究。本研究旨在分析皮下脂肪组织中PEPCK信使核糖核酸（mRNA）表达与肥胖相关代谢表型之间的相关性。我们收集了75名非糖尿病非绝经女性的人口统计学数据、生化变量及腹部皮下脂肪组织。以β-肌动蛋白作为对照，通过实时聚合酶链反应对相对PEPCK mRNA水平进行定量。无论是单变量分析（r = 0.413，P <.001）还是多变量线性回归分析（β =.978±.239，P <.001），皮下组织的PEPCK mRNA水平均与体重指数（BMI）呈正相关。PEPCK的mRNA表达也与体脂百分比（r = 0.436，P <.001）、血浆甘油三酯及总胆固醇水平呈正相关（P值均<.001）。然而，在校正BMI后，皮下组织中脂质谱与PEPCK表达之间的显著相关性消失。皮下PEPCK mRNA相对水平与空腹血糖、胰岛素以及用稳态模型评估法测得的胰岛素抵抗指数无关。总之，我们发现皮下脂肪组织中PEPCK mRNA表达与BMI、血浆甘油三酯及总胆固醇水平相关，但与胰岛素抵抗指数无关。
