COL6A3 expression in adipocytes associates with insulin resistance and depends on PPARγ and adipocyte size.

Objective: COL6A3 may modulate adipose tissue function in obesity and insulin resistance. A role for human adipocytes linking COL6A3 with insulin resistance warrants exploration.

Methods: COL6A3 mRNA in abdominal subcutaneous adipose samples was compared between (1) BMI-matched obese subjects resistant or sensitive to insulin (surgical whole tissue biopsies, n = 30/group), (2) lean/overweight and obese subjects (isolated adipocytes from collagenase-treated surgical biopsies, n = 11/group), (3) developing primary human adipocytes with/without knockdown of the insulin-sensitizing adipogenic gene PPARG (collagenase-treated lipoaspirate, n = 5), and (4) small and large adipocytes from lean/overweight subjects (collagenase-treated surgical biopsies or lipoaspirate, n = 10).