Targeting Iatrogenic Cushing's Syndrome With 11β-hydroxysteroid Dehydrogenase Type 1 Inhibition

Currently, 2-3% of the population of the United Kingdom and United States of America receive glucocorticoid therapy. Significant adverse effects are not confined to chronic use; recurrent short-course administration is associated with increased morbidity and mortality. The adverse metabolic features associated with glucocorticoid use include obesity, skeletal muscle myopathy, hypertension, insulin resistance and diabetes and are collectively termed 'iatrogenic Cushing's syndrome'. The efficacy of glucocorticoid therapy is not in doubt, but there are no interventions to reduce their metabolic consequences. Within metabolic tissues (liver, skeletal muscle, adipose), 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) regenerates active glucocorticoid and therefore is able to tightly control the availability of glucocorticoids to activate the glucocorticoid receptor. In preclinical studies, the investigators have shown that 11β-HSD1 is critical in regulating the development of the adverse features associated with circulating glucocorticoid excess, endorsing our observations in a patient with Cushing's disease, who was protected from a classical phenotype due to a functional deficit in 11β-HSD1. This study is the first clinical evaluation of the impact of the selective 11β-HSD1 inhibitor, AZD4017, in healthy volunteers taking exogenous glucocorticoids (prednisolone). The investigators propose that in tissues expressing high levels of 11β-HSD1, prednisolone action will be amplified, driving adverse effects within these tissues and have hypothesized that AZD4017 in humans will reduce the adverse metabolic consequences of Prednisolone administration without compromise to its anti-inflammatory action. Our specific research objectives are: 1. To demonstrate the beneficial effect of the selective 11β-HSD1 inhibitor, AZD4017, upon the prednisolone-induced deterioration in metabolic phenotype, including glucose disposal and endogenous glucose production rates. 2. To determine