mRNA levels of the insulin-signaling molecule SORBS1 in the adipose depots of nondiabetic women.

Objectives: The SORBS1 gene has been shown to be an important adaptor protein in the insulin-signaling pathway in many molecular and cellular biology studies. However, its roles in humans either in health or disease are rarely explored. In this report, we measured the SORBS1 mRNA levels in human adipose tissues.

Research Methods And Procedures: Adipose tissues of both the abdominal subcutaneous and omental depots were obtained from 62 nondiabetic women. The relative SORBS1 mRNA levels were quantified using real-time polymerase chain reaction.

Results: The relative SORBS1 mRNA levels from these two depots significantly correlated with each other (gamma = 0.85, p = 0.0000). The relative SORBS1 mRNA levels in the omental depots were lower than those in the subcutaneous depots (p = 0.053 by two-tailed test, p = 0.026 by one-tailed paired Student's t test). The mean SORBS1 expression level in the omental depots was approximately 70% that in the subcutaneous depots. Moreover, the relative SORBS1 mRNA levels in the omental depots were significantly related to BMI using either correlation analysis (gamma = -0.41, p = 0.0008) or multivariate linear regression analysis (beta = -0.20 +/- 0.09, p = 0.031) with adjustment for age, plasma glucose, serum insulin, triglyceride, and total cholesterol levels.

Discussion: Our preliminary results indicate the depot-specific differential expression of SORBS1 in relation to BMI. Further investigation of the functional significance of this phenomenon in human obesity is warranted.