The Cushing's disease adipose gene expression profile reveals effects of long term glucocorticoids on adipose tissue lipid, protein and glucose metabolism

Glucocorticoids have major effects on adipose tissue metabolism. To study tissue mRNA expression changes induced by chronic elevated endogenous glucocorticoids, we performed RNA sequencing on subcutaneous adipose tissue from patients with Cushing's disease (n=5) compared to patients with non-functioning pituitary adenomas (n=11). We found higher expression of transcripts involved in several metabolic pathways, including lipogenesis, proteolysis and glucose oxidation as well as decreased expression of transcripts involved in inflammation and protein synthesis. To further study this in a model system, we subjected mice to dexamethasone treatment for 12 weeks and analyzed their inguinal (subcutaneous) fat pads, which led to similar findings. Additionally, mice treated with dexamethasone showed drastic decreases in lean body mass as well as increased fat mass, further supporting the human transcriptomic data. These data provide insight to transcriptional changes that may be responsible for the co-morbidities associated with chronic elevations of glucocorticoids Overall design: DESIGN: Patients with cushing's (n=5) or non-functioning pituitary adenoma (n=11) were prospectively observed from March 2011 to June 2012.

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Hochberg I, Harvey I, Tran QT, Stephenson EJ, Barkan AL, Saltiel AR, Chandler WF, Bridges D