In the brain, angiotensinergic pathways play a major role in chronic regulation of cardiovascular and electrolyte homeostasis. Increases in plasma angiotensin II (Ang II), aldosterone, [Na+] and cytokines can directly activate these pathways. Chronically, these stimuli also activate a slow neuromodulatory pathway involving local aldosterone, mineralocorticoid receptors (MRs), epithelial sodium channels and endogenous ouabain (EO). This pathway increases AT1R and NADPH oxidase subunits and maintains/further increases the activity of angiotensinergic pathways. These brain pathways not only increase the setpoint of sympathetic activity per se, but also enhance its effectiveness by increasing plasma EO and EO-dependent reprogramming of arterial and cardiac function. Blockade of any step in this slow pathway or of AT1R prevents Ang II-, aldosterone- or salt and renal injury-induced forms of hypertension. MR/AT1R activation in the CNS also contributes to the activation of sympathetic activity, the circulatory and cardiac RAAS and increase in circulating cytokines in HF post MI. Chronic central infusion of an aldosterone synthase inhibitor, MR blocker or AT1R blocker prevents a major part of the structural remodeling of the heart and the decrease in LV function post MI, indicating that MR activation in the CNS post MI depends on aldosterone, locally produced in the CNS. Thus, Ang II, aldosterone and EO are not simply circulating hormones that act on the CNS but rather they are also paracrine neurohormones, locally produced in the CNS, that exert powerful effects in key CNS pathways involved in the long-term control of sympathetic and neuro-endocrine function and cardiovascular homeostasis.
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Frans H H Leenen, Mordecai P Blaustein, and John M Hamlyn
Sandra R Dahl, Ingrid Nermoen, Ingeborg Brønstad, Eystein S Husebye, Kristian Løvås, and Per M Thorsby
Immunoassays of steroid hormones are still used in the diagnosis and monitoring of patients with congenital adrenal hyperplasia. However, cross-reactivity between steroids can give rise to falsely elevated steroid levels. Here, we compare the use of immunoassays and liquid chromatography–tandem mass spectrometry (LC–MS/MS) in the monitoring of patients with classic 21-hydroxylase deficiency (21OHD). Steroid profiles in different mutation groups (genotypes) were also compared. Fifty-five patients with classic 21OHD (38 women) were studied. Blood samples were collected in the morning after an overnight medication fast. LC–MS/MS and immunoassays were employed to assay 17-hydroxyprogesterone (17OHP), testosterone and androstenedione. In addition, 21-deoxycortisol (21DF), 11-deoxycortisol (11DF), corticosterone, deoxycorticosterone, cortisone and cortisol were analyzed by LC–MS/MS. Testosterone, androstenedione and 17OHP levels were consistently lower (by about 30–50%) when measured by LC–MS/MS compared with immunoassays, with exception of testosterone in men. There was a significant correlation between 21DF and 17OHP (r = 0.87, P < 0.001), but three patients had undetectable 21DF. Subjects with no enzyme activity had significantly lower mean 11DF concentrations than subjects with residual activity. The use of LC–MS/MS gives a more specific view of adrenal steroid levels in 21OHD compared with immunoassays, which seem to considerably overestimate the levels of 17OHP and androstenedione. Falsely elevated levels of 17OHP and androstenedione could lead to overtreatment with glucocorticoids.
Kerry V Fanson, Tamara Keeley, and Benjamin G Fanson
In the context of reproduction, glucocorticoids (GCs) are generally considered to have negative effects. However, in well-studied model species, GCs fluctuate predictability across the estrous cycles, and short-term increases promote healthy ovarian function. Reproductive challenges have plagued captive elephant populations, which are not currently self-sustaining. Efforts to understand reproductive dysfunction in elephants have focused on the suppressive effects of cortisol, but the potential permissive or stimulatory effects of cortisol are unknown. In this study, we provide a detailed examination of cortisol patterns across the estrous cycle in Asian elephants (Elephas maximus). Time series analysis was used to analyze cortisol and progesterone data for a total of 73 cycles from eight females. We also compared cortisol profiles between females that successfully conceived and females that failed to conceive despite repeated mating attempts. Our results revealed that cortisol fluctuates predictably across the estrous cycle, with a peak during the second half of the follicular phase followed by low levels throughout the luteal phase. Furthermore, this pattern was significantly altered in nulliparous females; cortisol concentrations did not decline during the luteal phase to the same extent as in parous females. This study highlights the complexity of cortisol signaling and suggests future directions for understanding the role of cortisol in reproductive dysfunction.
Kathrin R Frey, Tina Kienitz, Julia Schulz, Manfred Ventz, Kathrin Zopf, and Marcus Quinkler
Patients with primary adrenal insufficiency (PAI) or congenital adrenal hyperplasia (CAH) receive life-long glucocorticoid (GC) therapy. Daily GC doses are often above the physiological cortisol production rate and can cause long-term morbidities such as osteoporosis. No prospective trial has investigated the long-term effect of different GC therapies on bone mineral density (BMD) in those patients.
To determine if patients on hydrocortisone (HC) or prednisolone show changes in BMD after follow-up of 5.5 years. To investigate if BMD is altered after switching from immediate- to modified-release HC.
Design and patients
Prospective, observational, longitudinal study with evaluation of BMD by DXA at visit1, after 2.2 ± 0.4 (visit2) and after 5.5 ± 0.8 years (visit3) included 36 PAI and 8 CAH patients. Thirteen patients received prednisolone (age 52.5 ± 14.8 years; 8 women) and 31 patients received immediate-release HC (age 48.9 ± 15.8 years; 22 women). Twelve patients on immediate-release switched to modified-release HC at visit2.
Prednisolone showed significantly lower Z-scores compared to HC at femoral neck (−0.85 ± 0.80 vs −0.25 ± 1.16, P < 0.05), trochanter (−0.96 ± 0.62 vs 0.51 ± 1.07, P < 0.05) and total hip (−0.78 ± 0.55 vs 0.36 ± 1.04, P < 0.05), but not at lumbar spine, throughout the study. Prednisolone dose decreased by 8% over study time, but no significant effect was seen on BMD. BMD did not change significantly after switching from immediate- to modified-release HC.
The use of prednisolone as hormone replacement therapy results in significantly lower BMD compared to HC. Patients on low-dose HC replacement therapy showed unchanged Z-scores within the normal reference range during the study period.
Karim Gariani, Pedro Marques-Vidal, Gérard Waeber, Peter Vollenweider, and François R Jornayvaz
Excessive glucocorticoid secretion has been associated with type 2 diabetes mellitus (T2DM) and other features of the metabolic syndrome. We aimed to evaluate whether basal or evening salivary cortisol may predict the occurrence of incident insulin resistance (IR) or T2DM.
This was a prospective, population-based study derived from the CoLaus/PsyCoLaus study including 1525 participants (aged 57.7 ± 10.3 years; 725 women). A total of 1149 individuals were free from T2DM at baseline. Fasting plasma glucose and insulin were measured after a follow-up of 5.3 years. Basal and evening salivary cortisol were measured at baseline. The association between basal or evening salivary cortisol level and incidence of IR or T2DM were analyzed by logistic regression, and the results were expressed for each independent variable as ORs and 95% CI.
After a median follow-up of 5.3 years, a total of 376 subjects (24.7%) developed IR and 32 subjects (2.1%) developed T2DM. Basal and evening salivary cortisol divided in quartiles were not associated with incidence of IR or T2DM. Multivariable analysis for age, gender, body mass index, physical activity and smoking status showed no association between basal or evening salivary cortisol and incidence of IR or T2DM.
In the CoLaus/PsyCoLaus study of healthy adults, neither basal nor evening salivary cortisol was associated with incident IR or T2DM.
Janko Sattler, Jinwen Tu, Shihani Stoner, Jingbao Li, Frank Buttgereit, Markus J Seibel, Hong Zhou, and Mark S Cooper
Patients with chronic immune-mediated arthritis exhibit abnormal hypothalamo-pituitary-adrenal (HPA) axis activity. The basis for this abnormality is not known. Immune-mediated arthritis is associated with increased extra-adrenal synthesis of active glucocorticoids by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme. 11β-HSD1 is expressed in the central nervous system, including regions involved in HPA axis regulation. We examined whether altered 11β-HSD1 expression within these regions contributes to HPA axis dysregulation during arthritis. The expression of 11β-HSD1, and other components of glucocorticoid signaling, were examined in various brain regions and the pituitary gland of mice with experimentally induced arthritis. Two arthritis protocols were employed: The K/BxN spontaneous arthritis model for chronic arthritis and the K/BxN serum transfer arthritis model for acute arthritis. 11β-HSD1 mRNA (Hsd11b1) was expressed in the hippocampus, hypothalamus, cortex, cerebellum and pituitary gland. Hypothalamic Hsd11b1 expression did not change in response to arthritis in either model. Pituitary Hsd11b1 expression was however significantly increased in both chronic and acute arthritis models. Hippocampal Hsd11b1 was decreased in acute but not chronic arthritis. Chronic, but not acute, arthritis was associated with a reduction in hypothalamic corticotropin-releasing hormone and arginine vasopressin expression. In both models, serum adrenocorticotropic hormone and corticosterone levels were no different from non-inflammatory controls. These findings demonstrate inflammation-dependent regulation of Hsd11b1 expression in the pituitary gland and hippocampus. The upregulation of 11β-HSD1 expression in the pituitary during both chronic and acute arthritis, and thus, an increase in glucocorticoid negative feedback, could contribute to the abnormalities in HPA axis activity seen in immune-mediated arthritis.
Filippo Ceccato, Elisa Selmin, Giorgia Antonelli, Mattia Barbot, Andrea Daniele, Marco Boscaro, Mario Plebani, and Carla Scaroni
The low-dose short synacthen test (LDSST) is recommended for patients with suspected central adrenal insufficiency (AI) if their basal serum cortisol (F) levels are not indicative of an intact hypothalamic–pituitary–adrenal (HPA) axis.
To evaluate diagnostic threshold for salivary F before and 30 min after administering 1 μg of synacthen, performed before 09:30 h.
A cross-sectional study from 2014 to 2020.
A tertiary referral university hospital.
In this study, 174 patients with suspected AI, 37 with central AI and 137 adrenal sufficient (AS), were included.
Main outcome measure
The diagnostic accuracy (sensitivity (SE), specificity (SP)) of serum and salivary F levels measured, respectively, by chemiluminescence immunoassay and liquid chromatography-tandem mass spectrometry.
Low basal serum or salivary F levels could predict AI. For the LDSST, the best ROC-calculated threshold for serum F to differentiate AI from AS was 427 nmol/L (SE 79%, SP 89%), serum F > 500 nmol/L reached SP 100%. A salivary F peak > 12.1 nmol/L after administering synacthen reached SE 95% and SP 84% for diagnosing central AI, indicating a conclusive reduction in the likelihood of AI. This ROC-calculated threshold for salivary F was similar to the 2.5th percentile of patients with a normal HPA axis, so it was considered sufficient to exclude AI. Considering AS those patients with salivary F > 12.1 nmol/L after LDSST, we could avoid unnecessary glucocorticoid treatment: 99/150 subjects (66%) had an inadequate serum F peak after synacthen, but salivary F was >12.1 nmol/L in 79 cases, who could, therefore, be considered AS.
Salivary F levels > 12.1 nmol/L after synacthen administration can indicate an intact HPA axis in patients with an incomplete serum F response, avoiding the need to start glucocorticoid replacement treatment.
Anastasia P Athanasoulia-Kaspar, Matthias K Auer, Günter K Stalla, and Mira Jakovcevski
Patients with non-functioning pituitary adenomas exhibit high morbidity and mortality rates. Growth hormone deficiency and high doses of glucocorticoid substitution therapy have been identified as corresponding risk factors. Interestingly, high levels of endogenous cortisol in, e.g., patients with post-traumatic stress disorder or patients with Cushing’s disease have been linked to shorter telomere length. Telomeres are noncoding DNA regions located at the end of chromosomes consisting of repetitive DNA sequences which shorten with aging and hereby determine cell survival. Therefore, telomere length can serve as a predictor for the onset of disease and mortality in some endocrine disorders (e.g., Cushing’s disease).
Here, we examine telomere length from blood in patients (n = 115) with non-functioning pituitary adenomas (NFPA) in a cross-sectional case–control (n = 106, age-, gender-matched) study using qPCR. Linear regression models were used to identify independent predictors of telomere length.
We show that patients with NFPA exhibited shorter telomeres than controls. No significant association of indices of growth hormone deficiency (IGF-1-level-SDS, years of unsubstituted growth hormone deficiency etc.) with telomere length was detected. Interestingly, linear regression analysis showed that hydrocortisone replacement dosage in patients with adrenal insufficiency (n = 52) was a significant predictor for shorter telomere length (β = 0.377; P = 0.018) independent of potential confounders (gender, age, BMI, arterial hypertension, systolic blood pressure, number of antihypertensive drugs, total leukocyte count, waist-to-hip ratio, waist circumference, diabetes mellitus type 2, HbA1c, current statin use). Median split analysis revealed that higher hydrocortisone intake (>20 mg) was associated with significantly shorter telomeres.
These observations strengthen the importance of adjusted glucocorticoid treatment in NFPA patients with respect to morbidity and mortality rates.
Paal Methlie, Steinar Hustad, Ralf Kellman, Bjørg Almås, Martina M Erichsen, Eystein S Husebye, and Kristian Løvås
Liquid chromatography–tandem mass spectrometry (LC–MS/MS) offers superior analytical specificity compared with immunoassays, but it is not available in many regions and hospitals due to expensive instrumentation and tedious sample preparation. Thus, we developed an automated, high-throughput LC–MS/MS assay for simultaneous quantification of ten endogenous and synthetic steroids targeting diseases of the hypothalamic–pituitary–adrenal axis and gonads.
Deuterated internal standards were added to 85 μl serum and processed by liquid–liquid extraction. Cortisol, cortisone, prednisolone, prednisone, 11-deoxycortisol, dexamethasone, testosterone, androstenedione and progesterone were resolved by ultra-high-pressure chromatography on a reversed-phase column in 6.1 min and detected by triple-quadrupole mass spectrometry. The method was used to assess steroid profiles in women with Addison's disease (AD, n=156) and blood donors (BDs, n=102).
Precisions ranged from 4.5 to 10.1% relative standard deviations (RSD), accuracies from 95 to 108% and extraction recoveries from 60 to 84%. The method was practically free of matrix effects and robust to individual differences in serum composition. Most postmenopausal AD women had extremely low androstenedione concentrations, below 0.14 nmol/l, and median testosterone concentrations of 0.15 nmol/l (interquartile range 0.00–0.41), considerably lower than those of postmenopausal BDs (1.28 nmol/l (0.96–1.64) and 0.65 nmol/l (0.56–1.10) respectively). AD women in fertile years had androstenedione concentrations of 1.18 nmol/l (0.71–1.76) and testosterone concentrations of 0.44 nmol/l (0.22–0.63), approximately half of those found in BDs of corresponding age.
This LC–MS/MS assay provides highly sensitive and specific assessments of glucocorticoids and androgens with low sample volumes and is suitable for endocrine laboratories and research. Its utility has been demonstrated in a large cohort of women with AD, and the data suggest that women with AD are particularly androgen deficient after menopause.
Masafumi Tetsuka and Misato Tanakadate
The bovine cumulus-oocyte complex (COC) is capable of converting cortisone, an inert glucocorticoid to active cortisol. This mechanism is mediated by 11β-hydroxysteroid oxidoreductase type 1 (HSD11B1), whose expression dramatically increases in the mature COC. In this study, we investigate the time course expression of HSD11B1 and the enzyme activity in the bovine COC undergoing maturation and fertilization in relation to key events taking place in the COC. Bovine COCs were subjected to in vitro maturation (IVM) and fertilization (IVF). The activities of HSD11B1 and HSD11B2, which mediates the opposite reaction, were measured using a radiometric conversion assay. In parallel studies, cumulus expansion, P4 production and the expression of genes associated with ovulation were measured. The reductive activity of HSD11B1 increased in the latter half of IVM and remained high during IVF, whereas the oxidative activity of HSD11B2 remained unchanged over both periods. Consequently, the net glucocorticoid metabolism in the bovine COC shifted from inactivation to activation around the time of ovulation and fertilization. The increase in HSD11B1 expression lagged behind that of P4 increase and cumulus expansion but ahead of the expressions of genes responsible for PGE2 synthesis. The reductive activity of HSD11B1 was well correlated with the cumulus expansion rate. This outcome indicates that the ability of the cumulus to activate glucocorticoids is related to its ability to synthesize hyaluronan. These results also indicate that the activation of HSD11B1 is an integral part of the sequential events taking place at the ovulation and fertilization in the bovine COC.