Endocrine Abstracts

In the endo/sarcoplasmic reticulum (ER/SR), hexose-6-phosphate dehydrogenase (H6PDH) generates an NADPH/ NADP ratio sufficient to drive 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1)-mediated glucocorticoid (GC) activation (11-DHC to corticosterone). In H6PDH knockout (H6PDKO) mice a reduced NADPH/NADP ratio leads to reversed 11β-HSD1 activity (corticosterone to 11-DHC), and GC insensitivity. They also display skeletal myopathy driven by activation of the un...

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inactive glucocorticoid to their active form (cortisone to cortisol in humans, 11-dehydrocorticosterone (11-DHC) to corticosterone in mice), and is dependent upon the presence of cofactor NADPH generated by the enzyme hexose-6-phosphate (H6PDH) for its activity. The 11β-HSD1/H6PDH system is implicated in the pathogenesis of the metabolic syndrome by generating tissue specific glucocorticoid excess. The ...

ACRD presents with clinical features of hyperandrogenism in females similar to those of PCOS (acne, hirsutism, oligomenorrhea, infertility), and precocious puberty in males. Obesity also occurs in some cases. Increased cortisol clearance leads to an increased hypothalamic-pituitary-adrenal axis drive resulting in elevated serum androgen levels and a decreased urinary cortisol metabolite: cortisone metabolite ratio below 0.5 (normal adult range 0.7–1.3). These observations...

Human studies indicate that local glucocorticoid (GC) generation within osteoblasts plays a critical role in various bone diseases. Human osteoblasts express the enzyme 11b-hydroxysteroid dehydrogenase type 1 (11b-HSD1) that converts inactive GCs (cortisone, dehydrocorticosterone) to their active counterparts (cortisol, corticosterone). This activation capacity critically depends on expression of a cofactor generating enzyme hexose-6-phosphate dehydrogenase. Enzyme expression ...

Glucocorticoids (GCs) have potent immunomodulatory and anti-inflammatory effects and are widely used in the treatment of inflammatory diseases. Unfortunately, their long term administration causes serious systemic metabolic side effects including osteoporosis, muscle wasting and insulin resistance. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is responsible for the local conversion of inactive GCs to their active counterparts. It has been shown that many of the...

11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is an NADPH-dependant oxo-reductase located in the sarcoplasmic reticulum (SR) lumen of skeletal muscle. It generates active glucocorticoids to regulate permissive and adaptive metabolism. Hexose-6-phosphate dehydrogenase (H6PD) interacts with 11β-HSD1 to generate an appropriate NADPH/NADP+ ratio to support activity. H6PD depletion impairs SR NADPH generation triggering 11β-HSD1 to assume glucocorticoid ina...

Local and systemic bone loss is a common complication in patients with chronic inflammatory disease. Previously, we have identified that glucocorticoid (GC) activation by the enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is increased within tissues such as bone during systemic inflammation. However, whilst effective at suppressing inflammation, in excess, GCs drive osteoporosis. To determine the contribution of 11β-HSD1 activated glucocorticoids to inf...

Glucocorticoids (GCs) have potent immunomodulatory and anti-inflammatory effects and are widely used in the treatment of inflammatory diseases. Unfortunately, their long term administration causes serious systemic metabolic side effects including osteoporosis, muscle wasting and insulin resistance. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is responsible for the local conversion of inactive GCs to their active counterparts. It has been shown that many of the...

11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is an NADPH-dependant oxo-reductase located in the sarcoplasmic reticulum (SR) lumen of skeletal muscle. It generates active glucocorticoids to regulate permissive and adaptive metabolism. Hexose-6-phosphate dehydrogenase (H6PD) interacts with 11β-HSD1 to generate an appropriate NADPH/NADP+ ratio to support activity. H6PD depletion impairs SR NADPH generation triggering 11β-HSD1 to assume glucocorticoid ina...

Local and systemic bone loss is a common complication in patients with chronic inflammatory disease. Previously, we have identified that glucocorticoid (GC) activation by the enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is increased within tissues such as bone during systemic inflammation. However, whilst effective at suppressing inflammation, in excess, GCs drive osteoporosis. To determine the contribution of 11β-HSD1 activated glucocorticoids to inf...