Endocrine Abstracts

Human studies have suggested that local glucocorticoid (GC) generation within osteoblasts plays a critical role in bone loss seen during aging, in response to inflammation and treatment with GCs. Human osteoblasts express the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) that converts inactive GCs (cortisone, dehydrocorticosterone, prednisone) to their active counterparts (cortisol, corticosterone, prednisolone). Enzyme expression increases with age, in r...

In humans, glucocorticoids (GC) are implicated in the pathogenesis of obesity and insulin resistance. GCs are regulated at the prereceptor level by 11beta-HSDs. 11beta-HSD1 predominately displays oxo-reductase activity (cortisone/11-dehydrocorticosterone to cortisol/ corticosterone), requiring the cofactor NADPH. Recently, studies in humans have shown that the enzyme H6PDH, by generating NAPDH in the endoplasmic reticulum (ER) is crucial for oxo-reductase activity. This study ...