Altered Expression of Aromatase and Estrogen Receptors in Adipose Tissue From Men With Obesity or Type 2 Diabetes.
Level 4 - case-series / case-control
Cross-sectional human tissue comparison with ex vivo laboratory experiments
PubMed 39833659 · doi:10.1210/clinem/dgaf038
What was done
Subcutaneous adipose tissue (SAT) biopsies were collected from men categorized by the presence or absence of obesity and type 2 diabetes. Researchers evaluated gene and protein expression of aromatase (ARO), estrogen receptor 1 (ESR1), and estrogen receptor 2 (ESR2) in SAT, and analyzed correlations with clinical markers of adiposity, glycemia, insulin resistance, and circulating sex hormones. In addition, SAT samples were treated ex vivo with estradiol (E2) or testosterone to measure basal and insulin-stimulated adipocyte glucose uptake.
What was found
The abstract reports directions of association without specific quantitative values, confidence intervals, or p-values: - ARO protein and gene expression were elevated in SAT from men with obesity compared to nonobese men and correlated positively with adiposity, hyperglycemia, and insulin resistance. - SAT ARO expression showed no association with circulating E2 concentrations. - Men with obesity exhibited lower SAT ESR1 expression and a decreased ESR1:ESR2 ratio, whereas ESR2 levels did not differ significantly between groups. - SAT ESR1 expression correlated negatively with adiposity, insulin resistance markers, and ARO expression, and tended to be lower in men with type 2 diabetes. - Ex vivo, E2 reduced insulin-stimulated glucose uptake, whereas testosterone increased basal glucose uptake in isolated adipocytes.
Why it matters
The study suggests that local estrogen synthesis and shifted estrogen receptor expression within adipose tissue, rather than circulating hormone levels alone, may play a direct functional role in insulin resistance and the pathogenesis of type 2 diabetes in men with obesity.
Limits
The abstract omits sample size, participant demographics, and exact quantitative effect sizes or p-values. The cross-sectional design cannot establish causality between altered receptor/aromatase expression and metabolic deterioration. Only subcutaneous adipose tissue was examined, leaving visceral depot biology unassessed, and ex vivo glucose uptake assays in isolated tissue may not fully capture systemic metabolic regulation.
Cited by
- supports Adipose tissue converts testosterone into forms of estrogen.