Pre-receptor Regulation of Cortisol in Hypothalamic-Pituitary-Adrenal Axis Functioning an Metabolism

Glucocorticoids (GCs) are ubiquitous, nuclear hormones, which are essential for life. In man, the main GC is cortisol, produced by the adrenals, endocrine glands that are situated on top of the kidneys. Cortisol exerts its functions in nearly all tissues and is crucial in the mediation of the stress response. Furthermore, cortisol is implicated in glucose and lipid metabolism, modulation of the immune system, maintenance of the vascular tone, bone formation, and skeletal and cardiac muscle function. Cortisol also aff ects brain function including memory modulation and mood regulation. Because of its anti-infl ammatory eff ects, cortisol and its synthetic analogues are now widely used in clinical practice. Indications include rheumatoid arthritis, infl ammatory bowel disease, sarcoidosis, asthma, and dermatological diseases. Additionally, GCs have an important role in prevention of graft versus host disease in organ transplant patients and haematological malignancies. Unfortunately, GC excess due to treatment or endogenous production, e.g. Cushing’s syndrome, has serious adverse eff ects, such as truncal obesity, striae, osteoporosis, hypertension, hypokalaemia, hyperglycaemia, mood disorders and when prescribed to children growth retardation

The very low-dose dexamethasone suppression test in the general population: A cross-sectional study

Determinants of the hypothalamic-pituitary-adrenal (HPA) axis functioning are increasingly explored in population-based studies. However, functional tests measuring the negative feedback of the HPA axis cannot easily be implemented into large observational studies. Furthermore, high doses of dexamethasone often completely suppress the HPA axis in healthy persons. This study aimed to detect the effects of the health, lifestyle and sociodemographic factors, psychiatric problems and cognitive functions on the negative feedback of the HPA axis using a very low-dose (0.25 mg) dexamethasone suppression test (DST). We evaluated the associations of several determinants with the saliva cortisol concentrations after dexamethasone intake in a confounder-adjusted model also corrected for baseline saliva cortisol concentrations in the Rotterdam Study, a large population-based study (N = 1822). We found that female sex, low income, lack of exercise, instrumental disability and smoking were all independently associated with stronger suppression of the HPA axis. Even though there were no linear associations between psychiatric measures and cortisol suppression, we found that depressive symptoms and anxiety disorders were more common in persons with non-suppression of cortisol. Conversely, psychotropic medication use was related to enhanced suppression of cortisol after DST. In this large study, we found that female gender, low socioeconomic status and poor health were all related to suppression of the HPA axis. Non-linear associations were detected between the suppression of the HPA axis and common psychiatric disorders in community-dwelling persons

The effect of common genetic variation in 11β-hydroxysteroid dehydrogenase type 1 on hypothalamic-pituitary-adrenal axis activity and incident depression

Background: Accumulating evidence suggests that hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA axis) is involved in depression. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inert cortisone to active cortisol and is implicated in HPA axis regulation in animal studies. The aim of our study was to identify polymorphisms in 11β-HSD1 gene (HSD11B1) with consistent associations with increased HPA axis activity and relate those polymorphisms to depression. Methods: Twelve single-nucleotide polymorphisms (SNPs), including 11 tagging SNPs, were selected using the HapMap database and genotyped in 4228 participants of the population-based Rotterdam Study. The outcome measures were salivary cortisol levels after awakening, 30 min later, at 1700 h, at bedtime, and plasma levels of androstenedione (in women only). SNPs that were significantly associated with cortisol as well as androstenedione levels were also related to incident depression. Results: rs11119328 was associated with higher cortisol saliva samples collected at bedtime as well as higher androstenedione levels (P value after correction for multiple testing: 0.01 and 0.04, respectively). Carriers of this polymorphism had an increased risk of an incident depression (hazard ratio 1.28, 95% confidence interval 1.03-1.59). Two other SNPs, which were in high linkage disequilibrium with rs11119328, were related to higher cortisol levels but not with androstenedione levels. Conclusions: We identified one SNP, which was associated with increased salivary cortisol levels at nadir as well as higher androstenedione levels. Moreover, this SNP was also associated with a higher risk of an incident depression. This suggests that 11β-HSD1 is implicated in human HPA axis regulation and susceptibility to depression. Copyrigh

Lack of Association of the 11beta-hydroxysteroid dehydrogenase type 1 gene 83,557insA and hexose-6-phosphate dehydrogenase gene R453Q polymorphisms with body composition, adrenal androgen production, blood pressure, glucose metabolism, and dementia.

CONTEXT: Recently, it was proposed that a combination of the 83,557insA polymorphism in the 11beta-hydroxysteroid dehydrogenase type 1 (HSD11B1) gene and the R453Q polymorphism in the hexose-6-phosphate dehydrogenase (H6PD) gene interacts to cause cortisone reductase deficiency (CRD) when at least three alleles are affected. OBJECTIVE: The aim was to study the separate and combined effects of these polymorphisms on body composition, adrenal androgen production, blood pressure, glucose metabolism, and the incidence of dementia in the healthy elderly population. DESIGN/SETTING/PARTICIPANTS: The Rotterdam study (n = 6105) and the Frail Old Men study (n = 347) are population-based cohort studies in the elderly. MAIN OUTCOME MEASURES: Genotype distributions and influences of (combined) genotypes on body mass index, adrenal androgen production, waist to hip ratio, systolic and diastolic blood pressure, fasting glucose levels, glucose tolerance test, and incidence of dementia were measured. RESULTS: No influence of the HSD11B1 83,557insA (allele frequencies 22.0 and 21.5%) and H6PD R453Q (allele frequencies 22.9 and 20.2%) variants was found for the different outcome measures that were investigated, either separately or when at least three alleles were affected. CONCLUSIONS: Two population-based studies among Caucasian elderly showed no evidence for (combined) effects of two polymorphisms in the HSD11B1 and H6PD genes on body composition, adrenal androgen production, blood pressure, glucose metabolism, and incidence of dementia. Moreover, the high frequencies observed for these two polymorphisms do not correspond to the low incidence of CRD observed in the general population. Altogether, it is unlikely that these polymorphisms cause CRD