This study investigated sex differences in adipose tissue insulin resistance. Men showed higher AdipolR values (an in vivo adipose insulin resistance index) than women, but only in the presence of obesity. In obese individuals, men exhibited lower adipocyte insulin sensitivity and maximal antilipolytic effect, along with a higher basal lipolysis rate. RNA sequencing revealed lower expression of insulin receptor substrate 1 (IRS1) in men. The findings suggest that in obesity, men's greater adipose insulin resistance involves less effective insulin inhibition of lipolysis, increased basal lipolysis, and reduced adipose IRS1 expression.

Peter Arner, Nathalie Viguerie, Lucas Massier, Mikael Rydén, Arne Astrup, Ellen Blaak, Dominique Langin, Daniel Peter Andersson