Laura Manenschijn

Clinical features associated with glucocorticoid receptor polymorphisms: An overview

The glucocorticoid receptor (GR) is crucial for the effects of glucocorticoids (GCs). Several polymorphisms of the GR are associated with altered sensitivity to GCs. For the ER22/23EK polymorphism, a relative GC resistance has been demonstrated. In vivo, this was suggested by a smaller response to a dexamethasone suppression test (DST), whereas in vitro experiments showed a diminished transactivational activity. The associated features of ER22/23EK carriers consist of favorable metabolic and body compositional conditions. In elderly subjects this polymorphism was associated with longevity and decreased risk of dementia. Interestingly, recent studies also showed an increased risk of major depression. In contrast, the N363S polymorphism was reported to be associated with an enhanced sensitivity to GCs, as was demonstrated by a DST. This polymorphism has also been associated with increased body mass index (BMI) and LDL‐cholesterol levels, as well as increased risk of cardiovascular disease. However, additional studies yielded conflicting results, showing no associations with being overweight. The BclI polymorphism is also associated with increased GC sensitivity. In addition, associations with increased abdominal fat mass, Crohns disease and, remarkably, major depression have been reported. Another GR polymorphism, located in exon 9β, is associated with increased expression and stabilization of the dominant negative splice variant GR‐β. Carriers of this polymorphism displayed a relative GC resistance in vitro as evidenced by diminished transrepressional activity, which is important for the immune system and inflammation. Associations have been found with increased inflammatory parameters, cardiovascular disease, and rheumatoid arthritis. In this article, studies concerning these clinically relevant GR variants are discussed.

Evaluation of a method to measure long term cortisol levels

INTRODUCTION Elevated levels of cortisol are known to induce various symptoms and diseases, e.g. abdominal obesity, type 2 diabetes, osteoporosis and cardiovascular disease. Measuring serum, saliva and urine cortisol is limited to one time point. Measurement of cortisol in scalp hair is a recently developed method to measure long term cortisol levels. The aim of this study was to investigate whether hair cortisol is a feasible parameter to measure cortisol exposure. EXPERIMENTAL We collected hair samples of 195 healthy individuals, 9 hypercortisolemic and one hypocortisolemic patient and measured hair cortisol levels. Cortisol was extracted from scalp hair using methanol and cortisol levels were measured using a salivary ELISA kit. Measurement of waist and hip circumferences and blood pressure was performed in 46 healthy subjects. RESULTS We found a positive correlation between hair cortisol and both waist circumference (r=0.392, p=0.007) and waist-to-hip ratio (WHR) (r=0.425, p=0.003). No correlations were found between hair cortisol levels and BMI, blood pressure or age. There was no decline in cortisol levels in six consecutive hair segments. Hair cortisol levels were elevated in patients with known hypercortisolism (p<0.0001). CONCLUSIONS Hair cortisol was positively correlated with WHR, suggesting that hair cortisol reflects cortisol exposure at tissue level, which was also supported by elevated hair cortisol levels in hypercortisolemic patients and concordance between hair cortisol levels and clinical disease course. Cortisol levels in hair are slightly influenced by hair treatment but not by natural hair colour, use of hair products, gender or age.

Glucocorticoid sensitivity in health and disease

Glucocorticoids regulate many physiological processes and have an essential role in the systemic response to stress. For example, gene transcription is modulated by the glucocorticoid–glucocorticoid receptor complex via several mechanisms. The ultimate biologic responses to glucocorticoids are determined by not only the concentration of glucocorticoids but also the differences between individuals in glucocorticoid sensitivity, which is influenced by multiple factors. Differences in sensitivity to glucocorticoids in healthy individuals are partly genetically determined by functional polymorphisms of the gene that encodes the glucocorticoid receptor. Hereditary syndromes have also been identified that are associated with increased and decreased sensitivity to glucocorticoids. As a result of their anti-inflammatory properties, glucocorticoids are widely used in the treatment of allergic, inflammatory and haematological disorders. The variety in clinical responses to treatment with glucocorticoids reflects the considerable variation in glucocorticoid sensitivity between individuals. In immune-mediated disorders, proinflammatory cytokines can induce localized resistance to glucocorticoids via several mechanisms. Individual differences in how tissues respond to glucocorticoids might also be involved in the predisposition for and pathogenesis of the metabolic syndrome and mood disorders. In this Review, we summarize the mechanisms that influence glucocorticoid sensitivity in health and disease and discuss possible strategies to modulate glucocorticoid responsiveness.

Shift Work at Young Age Is Associated with Elevated Long-Term Cortisol Levels and Body Mass Index

BACKGROUND The incidence of obesity and other features of the metabolic syndrome is increased in shift workers. This may be due to a misalignment between the internal circadian rhythm and the behavioral rhythm. The stress hormone cortisol could play a role in this phenomenon because it is secreted in a circadian rhythm, and long-term elevated cortisol leads to components of the metabolic syndrome. We compared cortisol levels in scalp hair of shift and day workers to study changes in long-term cortisol due to shift work. METHODS Hair samples were collected from 33 shift workers and 89 day workers. Cortisol was extracted from the hair samples with methanol, and cortisol levels were measured using ELISA. Height and weight were measured, and body mass index (BMI) was calculated. RESULTS Shift workers had higher hair cortisol levels than day workers: 47.32 pg/mg hair [95% confidence interval (CI) = 38.37-58.21] vs. 29.72 pg/mg hair (95% CI = 26.18-33.73) (P < 0.001). When divided in age groups based on the median age, elevated cortisol levels were present only in younger shift workers: 48.53 pg/mg hair (95% CI = 36.56-64.29) vs. 26.42 pg/mg hair (95% CI = 22.91-30.55) (P < 0.001). BMI was increased in younger shift workers as well: 27.2 (95% CI = 25.5-28.8) vs. 23.7 (95% CI = 22.8-24.7) in young day workers (P = 0.001). Hair cortisol and BMI were positively correlated (β = 0.262; P = 0.005). CONCLUSION Shift work at a young adult age is associated with elevated long-term cortisol levels and increased BMI. Elevated cortisol levels and BMI may contribute to the increased cardiovascular risk found in shift workers.

High Long-Term Cortisol Levels, Measured in Scalp Hair, Are Associated With a History of Cardiovascular Disease

BACKGROUND Stress is associated with an increased incidence of cardiovascular disease. The impact of chronic stress on cardiovascular risk has been studied by measuring cortisol in serum and saliva, which are measurements of only 1 time point. These studies yielded inconclusive results. The measurement of cortisol in scalp hair is a novel method that provides the opportunity to measure long-term cortisol exposure. Our aim was to study whether long-term cortisol levels, measured in scalp hair, are associated with cardiovascular diseases. METHODS A group of 283 community-dwelling elderly participants were randomly selected from a large population-based cohort study (median age, 75 y; range, 65-85 y). Cortisol was measured in 3-cm hair segments, corresponding roughly with a period of 3 months. Self-reported data concerning coronary heart disease, stroke, peripheral arterial disease, diabetes mellitus, and other chronic noncardiovascular diseases were collected. RESULTS Hair cortisol levels were significantly lower in women than in men (21.0 vs 26.3 pg/mg hair; P < .001). High hair cortisol levels were associated with an increased cardiovascular risk (odds ratio, 2.7; P = .01) and an increased risk of type 2 diabetes mellitus (odds ratio, 3.2; P = .04). There were no associations between hair cortisol levels and noncardiovascular diseases. CONCLUSIONS Elevated long-term cortisol levels are associated with a history of cardiovascular disease. The increased cardiovascular risk we found is equivalent to the effect of traditional cardiovascular risk factors, suggesting that long-term elevated cortisol may be an important cardiovascular risk factor.

A Novel Tool in the Diagnosis and Follow-Up of (Cyclic) Cushing's Syndrome: Measurement of Long-Term Cortisol in Scalp Hair

BACKGROUND Measurement of cortisol in 24-h urine collections and midnight saliva are standard screening tests for Cushings syndrome (CS). These tests reflect cortisol levels during a maximum of 24 h and do not provide historical information. Therefore, they can yield normal results in case of cyclic CS, which is a rare disorder that is characterized by alternating episodes of endogenous cortisol excess and normal cortisol secretion. The measurement of cortisol in scalp hair is a novel tool that might be helpful to establish the diagnosis of (cyclic) CS. Our aim was to study whether hair cortisol timelines correspond with clinical course in patients with CS and whether we could create retrospective timelines of cortisol exposure that correspond with symptomatic periods in patients suspected of cyclic CS. METHODS Scalp hair was collected in 14 patients with confirmed CS and six patients suspected of cyclic CS. Cortisol was extracted from the hair samples with methanol, and an ELISA was used to measure cortisol levels in hair extracts. A group of 96 nonobese individuals were used as a control group. RESULTS Hair cortisol levels were significantly elevated in CS patients (P<0.0001). Sensitivity and specificity of hair cortisol measurements for CS were 86 and 98%, respectively. Hair cortisol timelines of patients with CS and cyclic CS corresponded with clinical course. CONCLUSION Hair samples can provide a historical timeline that corresponds with clinical course in patients with (cyclic) CS. This new diagnostic tool can contribute significantly to early recognition of patients suffering from cyclic CS.

Long-term cortisol in bipolar disorder: associations with age of onset and psychiatric co-morbidity.

INTRODUCTION Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is hypothesized to play a role in the pathogenesis of bipolar disorder (BD). Conflicting results have been reported when saliva or serum was used to measure cortisol levels. A recently developed method is to measure cortisol in scalp hair, with 1cm of scalp hair representing 1 month. We studied whether there are differences in long-term hair cortisol levels between BD patients and healthy individuals and whether there are associations between hair cortisol and disease characteristics. METHODS Hair samples were collected in 100 BD patients and 195 healthy controls. Long-term cortisol levels were determined in 3 cm hair segments. Saliva samples were collected on two consecutive evenings. Documented disease characteristics were disease state, age of onset and psychiatric co-morbidity. RESULTS Hair cortisol levels were not statistically different in BD patients compared to healthy controls (p=0.233) and were not associated with the disease state at the moment of sample collection (p=0.978). In the subgroup of patients with age of onset ≥ 30 years, hair cortisol levels were significantly elevated compared to the subgroup with age of onset <30 years and to healthy controls (p=0.004). Psychiatric co-morbidity was associated with elevated cortisol levels (44.87 versus 31.41 pg/mg hair; p=0.021), with the exclusion of panic disorder, which was associated with decreased cortisol levels (22.13 versus 34.67 pg/mg hair; p=0.019). CONCLUSIONS Elevated long-term cortisol levels might play a role in a subgroup of patients with BD. There may be differences in pathogenesis of younger and older onset BD suggesting two different disease entities.

Functional polymorphism of the glucocorticoid receptor gene associates with mania and hypomania in bipolar disorder

OBJECTIVES In affective disorders, dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis is a frequently observed phenomenon. Subtle changes in glucocorticoid receptor (GR) functioning caused by polymorphisms of the GR gene (NR3C1) may be at the base of the altered reaction of the HPA axis to stress and subsequently related to the development and course of affective disorders. The aim of our study is to evaluate associations between GR gene polymorphisms and bipolar disorder (BD). METHODS In this study, 245 patients with BD were interviewed to confirm diagnosis and BD subtype. Data on medication use and sociodemographic details were also collected. The control group consisted of 532 healthy blood donors, from which data on sex and age were collected. To perform genotyping, blood was collected from all patients and healthy controls. RESULTS A trend was found for a protective effect of the exon 9beta polymorphism (p = 0.14) and the TthIIII polymorphism (p < 0.05) on the manifestation of the disease. These effects were significantly influenced by male gender for both polymorphisms. Patients with BD and the A/G variant in exon 9beta had significantly fewer manic and hypomanic episodes than noncarriers (p < 0.05). No further associations were found with the other investigated GR gene polymorphisms and BD. These findings were not corrected for multiple comparisons. CONCLUSIONS We conclude that the exon 9beta polymorphism and the TthIIII polymorphism of the GR gene may be associated with a protective effect on the clinical manifestation and course in patients with BD. Furthermore, no associations were found between the other studied GR gene polymorphisms and this disease.

Long-term cortisol levels measured in scalp hair of obese patients

In obese subjects a relatively high cortisol output in urine has been observed compared to nonobese individuals. However, cortisol levels in blood, saliva, and urine in association with obesity have been inconsistent across studies, possibly due to the high variability of systemic cortisol levels. Cortisol levels measured in scalp hair provide a marker for long‐term cortisol exposure, and have been associated with cardiovascular disease in an elderly population and to disease course in Cushings disease. We aimed to compare hair cortisol levels between obese patients and nonobese controls.

A Glucocorticoid Receptor Gene Haplotype (TthIII1/ER22/23EK/9β) Is Associated with a More Aggressive Disease Course in Multiple Sclerosis

CONTEXT In patients with multiple sclerosis (MS), glucocorticoids (GCs) might not be sufficiently able to restrain the immune system, possibly due to decreased GC sensitivity. This may be, at least partially, genetically determined. Previously, we reported a more aggressive disease course in patients with the glucocorticoid receptor (GR) gene ER22/23EK polymorphism, which has been shown to decrease GC sensitivity. OBJECTIVE In 646 MS patients and 317 healthy controls, we investigated whether haplotypes, including the ER22/23EK polymorphism or the GR 9beta polymorphism, which is also associated with a relative GC resistance, were associated with a more aggressive disease course. PATIENTS AND METHODS Polymorphisms in the GR gene (9beta, ER22/23EK, TthIIII, BclI, and N363S), which have previously been associated with altered GC sensitivity were determined and haplostructure was characterized. We evaluated whether the haplotypes were associated with disease susceptibility and several other disease characteristics. The association with disease progression was analyzed using Cox regression with time to Expanded Disability Status Score 6 as outcome. RESULTS None of the haplotypes was associated with disease susceptibility, age at onset, or onset type. Haplotype 6 (TthIIII, ER2223EK, and 9beta-G) was associated with a more rapid disease progression (hazard ratio 2.3; 95% confidence interval 1.5-3.7; P < 0.001). This seems to result from the presence of ER22/23EK, and not from the 9beta and TthIIII polymorphisms. CONCLUSIONS MS patients carrying the haplotype 6 (TthIIII, ER22/23EK, and 9beta) have a more aggressive disease course. This is probably due to the presence of the polymorphism ER22/23EK, which causes a decreased GC sensitivity.