Stress-related cortisol secretion in men: relationships with abdominal obesity and endocrine, metabolic and hemodynamic abnormalities

Genetically predicted plasma cortisol and common chronic diseases: A Mendelian randomization study

OBJECTIVE

Cushing's syndrome is characterized by hypercortisolaemia and is frequently accompanied by comorbidities such as type 2 diabetes, hypertension, osteoporosis, depression and schizophrenia. It is unclear whether moderate but lifelong hypercortisolaemia is causally associated with these diseases in the general population. We aimed to address this research gap using a Mendelian randomization approach.

METHODS

We used three cortisol-associated genetic variants in the SERPINA6/SERPINA1 region as genetic instruments in a two-sample, inverse-variance-weighted Mendelian randomization analysis. We obtained summary-level statistics for cortisol and disease outcomes from publicly available genetic consortia, and meta-analysed them as appropriate. We conducted a multivariable Mendelian randomization analysis to assess potential mediating effects.

RESULTS

A 1 standard deviation higher genetically predicted plasma cortisol was associated with greater odds of hypertension (odds ratio: 1.12; 95% confidence interval [CI]: 1.05-1.18) as well as higher systolic blood pressure (mean difference [MD]: 0.03 SD change; 95% CI: 0.01-0.05) and diastolic blood pressure (MD: 0.03 SD change; 95% CI: 0.01-0.04). There was no evidence of association with type 2 diabetes, osteoporosis, depression and schizophrenia. The association with hypertension was attenuated upon adjustment for waist circumference, suggesting potential mediation through central obesity.

CONCLUSION

There is strong evidence for a causal association between plasma cortisol and greater risk for hypertension, potentially mediated by obesity.

Expression of calcitonin gene-related peptide in atopic dermatitis and correlation with distress

BACKGROUND

Atopic dermatitis (AD) is a chronic, inflammatory, often severely itching skin disorder. It may worsen due to stress, depression, or anxiety. Calcitonin gene-related peptide (CGRP) may be involved in inflammation signaling. CGRP has also been suggested in relation to stress, depression, and anxiety. This study aimed to investigate the expression of CGRP in the skin of patients with AD.

METHODS

Twenty-seven adult patients with AD, characterized with clinical and psychodemographic parameters, were investigated regarding CGRP expression in skin biopsies, using an immunohistochemical technique.

RESULTS

The total number of CGRP-positive nerve-like fibers was found to be higher in lesional skin than in non-lesional skin. Moreover, more inflammatory cells of dendritic shape intruded into the epidermis in lesional skin compared to non-lesional skin. Keratinocytes showing expression of CGRP were also found in lesional skin. Interestingly, the number of CGRP-positive nerve-like fibers in lesional skin correlated with depressive and anxiety scores. Correlation with depressive score was also found for round CGRP-positive inflammatory cells in the epidermis.

CONCLUSIONS

CGRP may have a role in both the inflammatory process and distress, in AD.

The importance of the circadian trough in glucocorticoid signaling: a variation on B-flat

Glucocorticoid hormones are essential for health, but overexposure may lead to many detrimental effects, including metabolic, psychiatric, and bone disease. These effects may not only be due to increased overall exposure to glucocorticoids, but also to elevated hormone levels at the time of the physiological circadian trough of glucocorticoid levels. The late Mary Dallman developed a model that allows the differentiation between the effects of overall 24-hour glucocorticoid overexposure and the effects of a lack of circadian rhythmicity. For this, she continuously treated rats with a low dose of corticosterone (or "B"), which leads to a constant hormone level, without 24-hour overexposure using subcutaneously implanted pellets. The data from this "B-flat" model suggest that even modest elevations of glucocorticoid signaling during the time of the normal circadian trough of hormone secretion are a substantial contributor to the negative effects of glucocorticoids on health.

The Wistar Kyoto Rat: A Model of Depression Traits

There is an ongoing debate about the value of animal research in psychiatry with valid lines of reasoning stating the limits of individual animal models compared to human psychiatric illnesses. Human depression is not a homogenous disorder; therefore, one cannot expect a single animal model to reflect depression heterogeneity. This limited review presents arguments that the Wistar Kyoto (WKY) rats show intrinsic depression traits. The phenotypes of WKY do not completely mirror those of human depression but clearly indicate characteristics that are common with it. WKYs present despair- like behavior, passive coping with stress, comorbid anxiety, and enhanced drug use compared to other routinely used inbred or outbred strains of rats. The commonly used tests identifying these phenotypes reflect exploratory, escape-oriented, and withdrawal-like behaviors. The WKYs consistently choose withdrawal or avoidance in novel environments and freezing behaviors in response to a challenge in these tests. The physiological response to a stressful environment is exaggerated in WKYs. Selective breeding generated two WKY substrains that are nearly isogenic but show clear behavioral differences, including that of depression-like behavior. WKY and its substrains may share characteristics of subgroups of depressed individuals with social withdrawal, low energy, weight loss, sleep disturbances, and specific cognitive dysfunction. The genomes of the WKY and WKY substrains contain variations that impact the function of many genes identified in recent human genetic studies of depression. Thus, these strains of rats share characteristics of human depression at both phenotypic and genetic levels, making them a model of depression traits.

Association between Indoor Temperature in Winter and Serum Cholesterol: A Cross-Sectional Analysis of the Smart Wellness Housing Survey in Japan

AIM

Issuance of the WHO Housing and health guidelines has paralleled growing interest in the housing environment. Despite accumulating evidence of an association between outdoor temperature and serum cholesterol, indoor temperature has not been well investigated. This study examined the association between indoor temperature and serum cholesterol.

METHODS

We collected valid health checkup data of 2004 participants (1333 households), measured the indoor temperature for 2 weeks in winter, and divided participants according to whether they lived in a warm (average bedroom temperature ≥ 18℃), slightly cold (12-18℃) or cold house (＜12˚C). The relationship between bedroom temperature and serum cholesterol was analyzed using multivariate logistic regression models, adjusting for demographics, lifestyle habits and the season in which the health checkup was conducted, with a random effect of climate areas in Japan.

RESULTS

The sample sizes for warm, slightly cold, and cold houses were 206, 940, and 858, respectively. Compared to those in warm houses, the odds ratio of total cholesterol exceeding 220 mg/dL was 1.83 (95%CI: 1.23-2.71, p=0.003) for participants in slightly cold houses and 1.87 (95%CI: 1.25-2.80, p=0.002) in cold houses. Similarly, the odds ratio of LDL/non-HDL cholesterol exceeding the standard range was 1.49 (p=0.056)/1.67 (p=0.035) for those in slightly cold houses and 1.64 (p=0.020)/1.77 (p=0.021) in cold houses. HDL cholesterol and triglycerides were not significantly associated with bedroom temperature.

CONCLUSION

Besides lifestyle modification, improving indoor thermal environment through strategies such as installing high thermal insulation and appropriate use of heating devices may contribute to better serum cholesterol condition.

Changes in DNA Methylation of Clock Genes in Obese Adolescents after a Short-Term Body Weight Reduction Program: A Possible Metabolic and Endocrine Chrono-Resynchronization

Circadian rhythms are generated by a series of genes, collectively named clock genes, which act as a self-sustained internal 24 h timing system in the body. Many physiological processes, including metabolism and the endocrine system, are regulated by clock genes in coordination with environmental cues. Loss of the circadian rhythms has been reported to contribute to widespread obesity, particularly in the pediatric population, which is increasingly exposed to chronodisruptors in industrialized society. The aim of the present study was to evaluate the DNA methylation status of seven clock genes, namely clock, arntl, per1-3 and cry1-2, in a cohort of chronobiologically characterized obese adolescents (n: 45: F/M: 28/17; age ± SD: 15.8 ± 1.4 yrs; BMI SDS: 2.94 [2.76; 3.12]) hospitalized for a 3-week multidisciplinary body weight reduction program (BWRP), as well as a series of cardiometabolic outcomes and markers of hypothalamo-pituitary-adrenal (HPA) function. At the end of the intervention, an improvement in body composition was observed (decreases in BMI SDS and fat mass), as well as glucometabolic homeostasis (decreases in glucose, insulin, HOMA-IR and Hb1Ac), lipid profiling (decreases in total cholesterol, LDL-C, triglycerides and NEFA) and cardiovascular function (decreases in systolic and diastolic blood pressures and heart rate). Moreover, the BWRP reduced systemic inflammatory status (i.e., decrease in C-reactive protein) and HPA activity (i.e., decreases in plasma ACTH/cortisol and 24 h urinary-free cortisol excretion). Post-BWRP changes in the methylation levels of clock, cry2 and per2 genes occurred in the entire population, together with hypermethylation of clock and per3 genes in males and in subjects with metabolic syndrome. In contrast to the pre-BWRP data, at the end of the intervention, cardiometabolic parameters, such as fat mass, systolic and diastolic blood pressures, triglycerides and HDL-C, were associated with the methylation status of some clock genes. Finally, BWRP induced changes in clock genes that were associated with markers of HPA function. In conclusion, when administered to a chronodisrupted pediatric obese population, a short-term BWRP is capable of producing beneficial cardiometabolic effects, as well as an epigenetic remodeling of specific clock genes, suggesting the occurrence of a post-BWRP metabolic and endocrine chronoresynchronization, which might represent a "biomolecular" predictor of successful antiobesity intervention.

Which Clinical and Biochemical Parameters Are Associated with Lifetime Suicide Attempts in Bipolar Disorder?

Introduction: Bipolar Disorder (BD) is a disabling condition with suicidal behavior as one of the most common adverse outcomes. The purpose of the present research is to investigate the relationship between lifetime suicide attempts and the clinical factors/biochemical parameters in a large sample of bipolar patients. Methods: A total of 561 patients, consecutively hospitalized for BD in Milan and Monza (Italy), were recruited. Data about the demographic and clinical variables, as well as the values of blood analyses, were collected. The groups identified according to the presence/absence of lifetime suicide attempts were compared using univariate analyses. Then, three preliminary binary logistic regressions and a final logistic regression model were performed to identify the clinical and biochemical parameters associated with lifetime suicide attempts in BD. Results: Lifetime suicide attempts in BD were predicted by a longer duration of untreated illness (DUI) (p = 0.005), absence of lifetime psychotic symptoms (p = 0.025), presence of poly-substance use disorders (p = 0.033), comorbidity with obesity (p = 0.022), a last mood episode of manic polarity (p = 0.044), and lower bilirubin serum levels (p = 0.002); higher total cholesterol serum levels showed a trend toward statistical significance (p = 0.058). Conclusions: BD patients with lifetime suicide attempts present unfavorable clinical features. Some specific biochemical characteristics of bipolar patients may represent potential markers of suicidal behavior and need to be better investigated to identify new targets of treatment in the framework of personalized medicine. These preliminary findings have to be confirmed by further studies in different clinical settings.

Analysis of Genetic Variants in the Glucocorticoid Receptor Gene NR3C1 and Stenosis of the Carotid Artery in a Polish Population with Coronary Artery Disease

Background: Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Early diagnosis and elimination of risk factors are crucial for better managing CVDs. Atherosclerosis, whose development might be associated with glucocorticoids (GCs), is a critical factor in the development of carotid artery (CA) stenosis and most other CVDs. Aim: To investigate the association of Tth111I, N363S, and ER22/23EK-NR3C1 polymorphisms and the incidence of CA stenosis. Methods: The study group consisted of 117 patients diagnosed with coronary artery disease (CAD) and CA stenosis and 88 patients with CAD and ruled out CA stenosis. Genomic DNA was extracted from blood, and genotyping was carried out using Tth111I, N363S, and ER22/23EK-NR3C1 polymorphism sequencing. Results: No significant association between studied polymorphisms and the incidence or the severity of CA stenosis in the Polish population with CAD was found. Conclusion: This is the first study that proves that common NR3C1 gene variants do not influence CA stenosis and probably are not associated with atherosclerosis. The search for genes that can act as prognostic markers in predicting CA stenosis is still ongoing.

New Insights into the Role of Insulin and Hypothalamic-Pituitary-Adrenal (HPA) Axis in the Metabolic Syndrome

Recent data suggests that (pre)diabetes onset is preceded by a period of hyperinsulinemia. Consumption of the "modern" Western diet, over-nutrition, genetic background, decreased hepatic insulin clearance, and fetal/metabolic programming may increase insulin secretion, thereby causing chronic hyperinsulinemia. Hyperinsulinemia is an important etiological factor in the development of metabolic syndrome, type 2 diabetes, cardiovascular disease, polycystic ovarian syndrome, and Alzheimer's disease. Recent data suggests that the onset of prediabetes and diabetes are preceded by a variable period of hyperinsulinemia. Emerging data suggest that chromic hyperinsulinemia is also a driving force for increased activation of the hypothalamic-adrenal-pituitary (HPA) axis in subjects with the metabolic syndrome, leading to a state of "functional hypercortisolism". This "functional hypercortisolism" by antagonizing insulin actions may prevent hypoglycemia. It also disturbs energy balance by shifting energy fluxes away from muscles toward abdominal fat stores. Synergistic effects of hyperinsulinemia and "functional hypercortisolism" promote abdominal visceral obesity and insulin resistance which are core pathophysiological components of the metabolic syndrome. It is hypothesized that hyperinsulinemia-induced increased activation of the HPA axis plays an important etiological role in the development of the metabolic syndrome and its consequences. Numerous studies have demonstrated reversibility of hyperinsulinemia with lifestyle, surgical, and pharmaceutical-based therapies. Longitudinal studies should be performed to investigate whether strategies that reduce hyperinsulinemia at an early stage are successfully in preventing increased activation of the HPA axis and the metabolic syndrome.

Sexual Dimorphism in Adipose-Hypothalamic Crosstalk and the Contribution of Aryl Hydrocarbon Receptor to Regulate Energy Homeostasis

There are fundamental sex differences in the regulation of energy homeostasis. Better understanding of the underlying mechanisms of energy balance that account for this asymmetry will assist in developing sex-specific therapies for sexually dimorphic diseases such as obesity. Multiple organs, including the hypothalamus and adipose tissue, play vital roles in the regulation of energy homeostasis, which are regulated differently in males and females. Various neuronal populations, particularly within the hypothalamus, such as arcuate nucleus (ARC), can sense nutrient content of the body by the help of peripheral hormones such leptin, derived from adipocytes, to regulate energy homeostasis. This review summarizes how adipose tissue crosstalk with homeostatic network control systems in the brain, which includes energy regulatory regions and the hypothalamic–pituitary axis, contribute to energy regulation in a sex-specific manner. Moreover, development of obesity is contingent upon diet and environmental factors. Substances from diet and environmental contaminants can exert insidious effects on energy metabolism, acting peripherally through the aryl hydrocarbon receptor (AhR). Developmental AhR activation can impart permanent alterations of neuronal development that can manifest a number of sex-specific physiological changes, which sometimes become evident only in adulthood. AhR is currently being investigated as a potential target for treating obesity. The consensus is that impaired function of the receptor protects from obesity in mice. AhR also modulates sex steroid receptors, and hence, one of the objectives of this review is to explain why investigating sex differences while examining this receptor is crucial. Overall, this review summarizes sex differences in the regulation of energy homeostasis imparted by the adipose–hypothalamic axis and examines how this axis can be affected by xenobiotics that signal through AhR.

Hypothalamic-pituitary-adrenal axis activity and vascular function in healthy adults

OBJECTIVE

The objective of this study is to assess the relationship between hypothalamic-pituitary-adrenal (HPA) axis activity, vascular function and insulin sensitivity in healthy adults.

DESIGN

Open observational study.

PATIENTS

Thirty healthy adults were studied at the Endocrine Research Unit, Repatriation General Hospital, Adelaide, SA, Australia.

MEASUREMENTS

HPA activity was assessed from the serum cortisol 30 min after 1 µg ACTH_1-24 (Novartis Pharmaceuticals). Subjects with a cortisol below (n = 15) and above (n = 15) the median were categorized as low and high responders, respectively. Reactive hyperaemia index (RHI) was measured fasting to estimate endothelial function. Matsuda index was calculated from glucose and insulin concentrations collected fasting and 30 minutely for 2 h after a mixed meal (10 kcal/kg, 45% carbohydrate, 15% protein, 40% fat). The primary endpoint was the difference in RHI between low and high responders.

RESULTS

There were no significant differences in age (61 ± 9 vs. 64 ± 7 years, p = .19), body mass index (BMI; 26 ± 3 vs. 24 ± 4 kg/m² , p = .25) and sex (p = .71) between low and high responders. High responders had a lower RHI (2.1 ± 0.2 vs. 2.6 ± 0.2, p = .04) than low responders and there was a negative association between RHI and peak cortisol post ACTH_1-24 (β = -.56, p < .01). There were no significant differences in Matsuda index (15.0 ± 2.4 vs. 22.7 ± 5.2, p = .19) between high and low responders.

CONCLUSION

In healthy adults, endothelial dysfunction is likely to contribute to the association between HPA hyperactivity and increased cardiovascular risk. As insulin sensitivity was not different in high and low responders, endothelial dysfunction is not primarily secondary to insulin resistance.

Heat exposure and workers' health: a systematic review

OBJECTIVES

Several studies on the health effects of heat exposure on workers have been reported; however, only few studies have summarized the overall and systematic health effects of heat exposure on workers. This study aims to review the scientific reports on the health status of workers exposed to high temperatures in the workplace.

METHODS

We reviewed literature from databases such as PubMed and Google Scholar, using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines to identify studies that address health effects of heat exposure among workers.

RESULTS

In total, 459 articles were identified, and finally, 47 articles were selected. Various health effects of heat exposure on workers have been reported, such as heat-related diseases, deaths, accidents or injuries, effects on the urinary system, reproductive system, and on the psychological system.

CONCLUSIONS

Our review suggests that many workers are vulnerable to heat exposure, and this has a health effect on workers.

Corticosterone induces obesity partly via promoting intestinal cell proliferation and survival

INTRODUCTION

A vicious cycle ensues whereby prolonged exposure to social stress causes increased production of glucocorticoids (GCs), leading to obesity even further. Understanding the role of GCs, the key element in the vicious circle, might be helpful to break the vicious circle. However, the mechanism by which GCs induce obesity remains elusive.

METHODS

Corticosterone (CORT) was administered to mice for 8 weeks. Food and water intake were recorded; obesity was analyzed by body-weight evaluation and magnetic resonance imaging (MRI); intestinal proliferation and survival were evaluated by H&E staining, EdU-progression test, TUNEL assay and immunofluorescence staining of Ki67 and CC3; RNA-seq was performed to analyze transcriptional alterations in small intestines and livers.

RESULTS

Chronic CORT treatment induced obesity, longer small intestines, hepatic steatosis and elevated levels of serum insulin and leptin in mice; CORT-treated mice showed increased cell proliferation and decreased apoptosis of small intestines; RNA-seq results indicate that differentially expressed genes (DEGs) were enriched in several cell growth/death-associated signaling pathways.

DISCUSSION

Herein we find that administration of CORT to mice promotes the proliferation and survival of intestinal cells, which might contribute to the longer small intestines and the elongated intestinal villi, thus leading to increased nutrient absorption and obesity in mice. Understanding CORT-induced alterations in intestines and associated signaling pathways might provide novel therapeutic clues for GCs or stress-associated obesity.

Race/ethnicity, gender and the SES gradient in BMI: The diminishing returns of SES for racial/ethnic minorities

Using the 2013-2016 data from the National Health and Nutrition Examination Survey (NHANES), this study uses the case of obesity to examine whether and to what extent racial and ethnic minorities experience fewer benefits from higher SES relative to their white counterparts. Study results provide support for the diminishing returns in health hypothesis and add an intersectional dimension to this perspective by uncovering stark gendered racial/ethnic disparities in BMI. Specifically, research findings demonstrate that higher income and education is associated with lower BMI among white but not black or Mexican American adults. The most substantial decrease in BMI associated with increase in individual-level SES was observed among white women. Taken together, empirical evidence from this study underscores difficulty in overcoming adverse health effects of lower ascribed status (i.e. gender or race/ethnicity) even with attainment of higher achieved social status (i.e. educational attainment or income) and offers promising avenues for future research on identifying complex hierarchies that shape population health outcomes.

The Window Matters: A Systematic Review of Time Restricted Eating Strategies in Relation to Cortisol and Melatonin Secretion

Time-Restricted Eating is an eating pattern based on the circadian rhythm which limits daily food intake (usually to ≤12 h/day), unique in that no overt restriction is imposed on the quality, nor quantity, of food intake. This paper aimed to examine the effects of two patterns of TRE, traditional TRE, and Ramadan fasting, on two markers of circadian rhythm, cortisol and melatonin. PubMed and Web of Science were searched up to December 2020 for studies examining the effects of time restricted eating on cortisol and melatonin. Fourteen studies met our inclusion criteria. All Ramadan papers found statistically significant decrease in melatonin (p < 0.05) during Ramadan. Two out of the three Ramadan papers noted an abolishing of the circadian rhythm of cortisol (p < 0.05). The non-Ramadan TRE papers did not examine melatonin, and cortisol changes were mixed. In studies comparing TRE to control diets, Stratton et al. found increased cortisol levels in the non-TRE fasting group (p = 0.0018) and McAllister et al. noted no difference. Dinner-skipping resulted in significantly reduced evening cortisol and non-significantly raised morning cortisol. Conversely, breakfast skipping resulted in significantly reduced morning cortisol. This blunting indicates a dysfunctional HPA axis, and may be associated with poor cardio-metabolic outcomes. There is a paucity of research examining the effects of TRE on cortisol and melatonin. The contrasting effect of dinner and breakfast-skipping should be further examined to ascertain whether timing the feeding window indeed has an impact on circadian rhythmicity.

Relationship between Sleep Duration Trajectories and Self-Rated Depressive Symptoms in South Koreans with Physical Disabilities

Physically disabled persons can have sleep problems, which affects their mental health more than those in non-disabled people. However, there are few studies on the relationship between sleep duration and mental health targeting physically disabled people in South Korea, and existing studies on the disabled have mostly used data collected from convenience rather than nationally representative samples, limiting the generalization of the results. This study used data from the second wave of the Panel Survey of Employment for the Disabled (PSED, 2016-2018, 1st-3rd year). Participants included 1851 physically disabled individuals. The Chi-square test and generalized estimating equation (GEE) were used and the Akaike information criterion (AIC) value and the AIC log Bayes factor approximation were used to select sleep trajectories. This is the first study to elucidate multiple sleep trajectories in physically disabled people in Korea, and the relationship between sleep duration trajectories and self-rated depressive symptoms. People with physical disabilities who sleep more than 9 h have the highest risk of depression and need more intensive management as a priority intervention.

Hair cortisol levels in posttraumatic stress disorder and metabolic syndrome

Individuals with post-traumatic stress disorder (PTSD) evidence increased rates of metabolic syndrome (MetS), and both PTSD and MetS are associated with alterations in hypothalamic-pituitary-adrenal (HPA) axis function. Few investigations have examined the possible role of HPA-axis dysfunction in the co-occurrence of PTSD and MetS. In a case-control study, we aimed to determine whether hair cortisol concentrations (HCC) were associated with (i) PTSD caseness and severity and (ii) PTSD and MetS co-occurrence. We used the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) to determine PTSD diagnoses and severity scores in 216 females of mixed ancestry aged between 20 and 79 years (M = 43.8, SD =13.3). Hair samples, representing a three-month retrospective window of cortisol levels, were obtained and analyzed utilizing liquid chromatography-tandem mass spectrometry. We constructed multivariate linear regression models to evaluate whether PTSD diagnosis, PTSD severity, and MetS comorbidity were associated with HCC, controlling for potential confounders. HCC were significantly higher (adj β = 0.154, p = .033; Cohen's d = 0.44) in PTSD patients (n = 110) than trauma-exposed controls (n = 106) and CAPS severity scores (adj β = 0.207, p = .005) were significantly associated with HCC. MetS was not associated with HCC and there were no significant interactions between PTSD and MetS on HCC. This study provides evidence of a chronically dysregulated neuroendocrine mediated stress response in PTSD, with a clear dose-response relationship. HCC do not, however, appear to have specificity for the comorbidity of PTSD and MetS in this sample.LAY SUMMARYWe found that levels of the stress hormone, cortisol, measured in hair samples were significantly higher in South African women with post-traumatic stress disorder (PTSD) than in women who had also experienced trauma but did not have PTSD. Hair cortisol levels were, however, not associated with metabolic syndrome, a cluster of risk factors for heart disease, in the women studied. We thus show that South African women with PTSD have elevated long-term stress hormone levels and that this effect is related to PTSD and not solely due to trauma exposure.

Psychological Profile and Distinct Salivary Cortisol Awake Response (CAR) in Two Different Study Populations with Obstructive Sleep Apnea (OSA) and Central Serous Chorioretinopathy (CSC)

Obstructive sleep apnea (OSA) and central serous chorioretinopathy (CSC) are in terms of nosography different pathologies, however they share a stress-related physio-pathogenetic component, not yet explored in depth. Therefore, the aim of the present study was to ascertain whether OSA and CSC share a common profile, specifically in cortisol production focusing on the cortisol awake response (CAR), the area under curve (AUC_CAR) and the SLOPE_CAR compared with healthy matched controls. Furthermore, standardized self-administered questionnaires were used to identify mental health status related to depression, anxiety and subjective stress perception levels in the study populations. The results showed hypothalamus-pituitary-adrenal (HPA) axis activity anomalies, represented by a flattening CAR in the OSA group and a statistically significant increase in cortisol production in CSC patients at awakening. This disarrangement of the HPA axis activity associated with elevated distress and mental health scores, and its presence in both patients with OSA and patients with CSC, might represent the shared path explaining the stress-related component in these diseases. Further research is needed to investigate the psycho-neuro-endocrinological aspects of OSA and CSC to determine whether psychoeducation on effective stress coping strategies might be of value in improving the quality of life of OSA and CSC patients.

Relationship between Cortisol Changes during the Night and Subjective and Objective Sleep Quality in Healthy Older People

The aim of this study was to investigate whether the nighttime cortisol release was associated with subjective and objective sleep quality and the discrepancy between them. Forty-five healthy older adults (age range from 56 to 75 years) collected salivary samples immediately before sleep and immediately after awakening on two consecutive nights. Actigraphy was used to assess objective sleep quality and quantity. A sleep diary was used to assess subjective sleep quality. Linear mixed models were performed using subjective and objective sleep quality data from 76 nights to investigate between-subject associations. We observed that larger changes in cortisol levels between sleep onset and awakening, reflecting a healthier circadian rhythm of the Hypothalamic-Pituitary-Adrenal (HPA) axis, were associated with better subjective sleep quality, but not with objective sleep quality. Moreover, smaller changes in nighttime cortisol were associated with lower subjective sleep quality relative to objective sleep quality. All these results were observed even after controlling for important confounders such as sleep quantity, age, sex, subjective socioeconomic status, stress perception, depression, physical activity, and adherence to the salivary sampling protocol. This study demonstrates that subjective sleep quality in older people may be explained, to some extent, by the activity of the HPA axis.

Unequal Protective Effects of Parental Educational Attainment on the Body Mass Index of Black and White Youth

BACKGROUND

Parental educational attainment is shown to be protective against health problems; the Minorities' Diminished Returns theory, however, posits that these protective effects tend to be smaller for socially marginalized groups particularly blacks than whites.

AIMS

To explore racial differences in the effect of parental educational attainment on body mass index (BMI) in a national sample of US adolescents.

METHODS

In this cross-sectional study, we used baseline data of 10,701 (8678 white and 2023 black) 12-17 years old adolescents in the Population Assessment of Tobacco and Health (PATH; 2013). Parental educational attainment was the predictor. Youth BMI (based on self-reported weight and height) was the dependent variable. Age, gender, ethnicity, and family structure were covariates. Race was the focal moderator.

RESULTS

Overall, higher parental educational attainment was associated with lower youth BMI. Race, however, moderated the effect of parental educational attainment on BMI, suggesting that the protective effect of parental educational attainment on BMI is significantly smaller for black than white youth.

CONCLUSIONS

In the United States, race alters the health gains that are expected to follow parental educational attainment. While white youth who are from highly educated families are fit, black youth have high BMI at all levels of parental educational attainment. This means, while the most socially privileged group, whites, gain the most health from their parental education, blacks, the least privileged group, gain the least. Economic, social, public, and health policymakers should be aware that health disparities are not all due to lower socioeconomic status (SES) of the disadvantaged group but also diminished returns of SES resources for them. Black-white health disparities exist across all high socioeconomic status (SES) levels.

Adrenoceptor-related decrease in serum triglycerides is independent of PPARα activation

Adrenoceptor (AR)-linked pathways belong to the major components of the stress response system and are associated with the pathophysiology of diseases within the spectrum of metabolic syndrome. In this study, the role of adrenoceptor stimulation in serum triglyceride (TG) regulation in mice was investigated. For this purpose, α₁ -ARs were activated with phenylephrine (PH) and β_1/2 -ARs with isoprenaline (ISOP). Both AR agonists markedly reduced serum TG levels independently of PPARα activation. These drugs also significantly activated the hormone-sensitive lipase in the white adipose tissue indicating increased mobilization of TGs in this tissue. In addition, PH and ISOP up-regulated Lpl, Nr4A, Dgat1, Mttp, Aadac and Cd36 genes, critical in TG regulation, whereas the observed decrease in serum TG levels was independent of the hepatic very low-density lipoprotein (VLDL)-TG secretion. Interestingly, PH and ISOP also inactivated the hepatic insulin/PI3k/AKT/FoxO1 signaling pathway, holding a critical role in the regulation of genes involved in TG synthesis. Taken together, the findings of the present study indicate that stimulation of α₁ - and β_1/2 -ARs markedly reduced serum TG steady-state levels as a result of alterations in TG synthesis, uptake, transport, hydrolysis, metabolism and clearance, an effect induced by PPARα independent mechanisms.

Monosodium l-glutamate-obesity onset is associated with disruption of central control of the hypothalamic-pituitary-adrenal axis and autonomic nervous system

The hypothalamic-pituitary-adrenal axis (HPA) exerts important catabolic peripheral effects and influences autonomic nervous system (ANS)-mediated processes. Impaired negative-feedback control or reduced HPA axis sensitivity and altered ANS activity appear to be associated with the development and maintenance of obesity. In the present study, we examined the hypothesis that the central HPA axis is dysregulated favouring ANS disbalance in monosodium l-glutamate (MSG)-induced rat obesity. Glucose homeostasis, corticosterone, leptin and ANS electrical activity were evaluated. Adult MSG-induced obese rats exhibited fasting hyperinsulinaemia, insulin resistance, glucose intolerance, hypercorticosteronaemia, hyperleptinaemia and altered ANS activity. A decrease in food intake was observed during corticotrophin-releasing hormone (CRH) treatment in both control and MSG-treated rats. By contrast, food intake was significantly elevated in control rats treated with dexamethasone (DEXA), whereas no alterations were observed following DEXA treatment in MSG-induced obese rats. After DEXA injection, an increase in fasting insulin and glucose levels, associated with insulin resistance, was seen in both groups. As expected, there was a decrease of parasympathetic activity and an increase of sympathetic nervous activity in CRH-treated control animals and the opposite effect was seen after DEXA treatment. By contrast, there was no effect on ANS activity in MSG-rats treated with CRH or DEXA. In conclusion, impairment of the HPA axis can lead to disbalance of ANS activity in MSG-treated rats, contributing to the establishment and maintenance of obesity.

Association between Cigarette Smoking and Sarcopenia according to Obesity in the Middle-Aged and Elderly Korean Population: The Korea National Health and Nutrition Examination Survey (2008-2011)

Background

The definition of sarcopenia focuses on muscle mass and function. Sarcopenic obesity is the relative excess of fat tissue with decreased muscle mass. We examined the association between cigarette smoking and sarcopenia according to obesity in middle-aged and elderly Koreans.

Methods

We conducted a cross-sectional study of 9,385 subjects (age ≥50 years) based on data from the fourth and fifth Korea National Health and Nutrition Examination Surveys (2008–2011). Smoking groups were categorized by smoking status and the number of cigarettes smoked daily. Sarcopenia was defined as weight-adjusted appendicular skeletal muscle mass of 2 standard deviations below the sex-specific mean for young adults. Obesity was defined as fat mass ≥30% for men and ≥40% for women. Subjects were categorized into three groups: sarcopenic obese (SO), sarcopenic non-obese (SNO), and normal. Multiple logistic regression analysis was performed to assess the association between smoking and SNO and SO.

Results

Among men, current smokers were more associated with SNO than never-smokers (adjusted odds ratio [OR], 3.34; 95% confidence interval [CI], 1.09–10.26). However, there was no significant association between smoking status and SNO in women or SO in either sex. Among current smokers, moderate smokers (11–20 cigarettes/d) were more likely to be SNO (adjusted OR, 5.81; 95% CI, 1.12–30.31) and heavy smokers (>20 cigarettes/d) were more likely to be SO (adjusted OR, 9.53; 95% CI, 1.65–55.01) than light smokers (<11 cigarettes/d).

Conclusion

In men, smoking was positively associated with SNO, and heavy smokers were more likely to be SO than light smokers.

Involvement of Hepatic SHIP2 and PI3K/Akt Signalling in the Regulation of Plasma Insulin by Xiaoyaosan in Chronic Immobilization-Stressed Rats

Background: Long-term exposure to chronic stress is thought to be a factor closely correlated with the development of metabolic disorders, such as diabetes mellitus and metabolic syndrome. Xiaoyaosan, a Chinese herbal formula, has been described in many previous studies to exert anxiolytic-like or antidepressant effects in chronically stressed rats. However, few studies have observed the effects of Xiaoyaosan on the metabolic disorders induced by chronic stress. Objective: We sought to investigate the effective regulation of Xiaoyaosan on 21-day chronic immobility stress (CIS, which is 3 h of restraint immobilization every day)-induced behavioural performance and metabolic responses and to further explore whether the effects of Xiaoyaosan were related to SHIP2 expression in the liver. Methods: Sixty male Sprague Dawley rats were randomly divided into a control group, a CIS group, a Xiaoyaosan group and a rosiglitazone group. The latter three groups were subjected to 21 days of CIS to generate the stress model. After 21 days of CIS, the effects of Xiaoyaosan on body weight, food intake, and behaviour in the open field test, the sucrose preference test and the forced swimming test were observed following chronic stress. Plasma insulin, cholesterol (CHOL), triglyceride (TG), low-density lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) concentrations and blood glucose were examined, and the protein and mRNA expression levels of SHIP2, p85 and Akt in the liver were measured using RT-qPCR and immunohistochemical staining. Results: Rats exposed to CIS exhibited depression-like behaviours, decreased levels of plasma insulin, CHOL, LDL-C, TG and HDL-C, and increased blood glucose. Increased SHIP2 expression and reduced Akt, p-Akt and p85 expression were also observed in the liver. Xiaoyaosan exerted antidepressant effects and effectively reversed the changes caused by CIS. Conclusions: These results suggest that Xiaoyaosan attenuates depression-like behaviours and ameliorates stress-induced abnormal levels of insulin, blood glucose, CHOL, LDL-C and HDL-C in the plasma of stressed rats, which may be associated with the regulation of SHIP2 expression to enhance PI3K/Akt signalling activity in the liver.

Salivary alpha-amylase and hormones levels of young adults with different body composition

The aim of this study was to assess the differences in salivary biomarker levels of young adults classified according to body fat accumulation. One hundred and thirty-four volunteers were evaluated (mean age 21 ± 2 years). Body composition was calculated through skinfold thickness: supra-iliac, biceps, and triceps, sub-scapular. Body fat percentage (BF%) was used to classify subjects according to fat tissue accumulation: normal-weight (n = 37, 19 females, 18 males), overweight (n = 42, 30 females, 12 males), and obese (n = 55, 42 females, 13 males). Saliva samples were collected 30 min after awakening to determine salivary levels of 17-beta-estradiol. For salivary cortisol and alpha-amylase activity (sAA) three samples were obtained, just after awakening, 30 min after awakening and at bedtime. Oral contraceptive intake was considered for the female group. The results showed that overweight and obese females using oral contraceptive presented lower levels of 17-β-estradiol than normal-weight females. In overweight and obese males, sAA levels were higher 30 min post-awakening when compared with the normal-weight group. The comparison of sAA levels within time showed no difference for males; obese females showed significant higher values at bedtime than 30 min post-awakening. The salivary cortisol concentration showed higher values at morning decreasing significantly at bedtime for all groups. Concluding, differences in 17-β-estradiol and sAA levels were found in females and males, respectively, according to body fat accumulation, showing the usefulness of salivary biomarkers in the study of systemic conditions. PRACTICAL APPLICATIONS: Saliva is an advantageous biological fluid in innovative methods for diagnosis. Besides being a noninvasive method, salivary steroid measurements have the potential to provide a convenient assessment of serum free steroid concentrations.

History of Non-Fatal Physical Assault Is Associated with Premature Mortality for Whites but Not Blacks

Exposure to trauma increases the long-term risk of mortality, and experiencing non-fatal physical assault is not an exception. To better understand population heterogeneity in this link, the current study explored Black–White differences in the association between history of non-fatal physical assault and risk of all-cause mortality over a 25-year period in the United States. Data came from the Americans’ Changing Lives (ACL) study that followed 3617 non-institutionalized respondents for up to 25 years. History of non-fatal physical assault at baseline was the predictor. Outcome was time to death due to all-cause mortality during follow-up from baseline (1986) to follow-up (2011). Confounders included gender, age, and baseline socio-economic status (education and income), health behaviors (smoking and drinking), and health status (chronic medical conditions, self-rated health, and body mass index). Race was the moderator. Cox regressions were used for multi-variable analysis. History of non-fatal physical assault at baseline was associated with an increased risk of mortality, above and beyond baseline socioeconomic status, health behaviors, and health status. Race interacted with history of non-fatal physical assault on mortality, suggesting a stronger effect for Whites compared to Blacks. In race-specific models, history of non-fatal physical assault was associated with risk of mortality for Whites but not Blacks. The current study showed that experiencing non-fatal physical assault increases the risk of premature death above and beyond demographics, socioeconomic status, health behaviors, and health status. Experiencing non-fatal physical assault may have a larger effect on premature mortality among Whites than Blacks. Future research is needed on how Blacks and Whites differ in the health consequences of social adversities.

Cortisol Stress Reactivity to the Trier Social Stress Test in Obese Adults

OBJECTIVE

Approximately 600 million adults worldwide suffer from obesity. In addition to individual's eating behavior and lack of physical activity in the development of obesity and overweight, psychosocial stress as well as hormonal stress reactivity must also be considered as important contributing factors. In the current study we compared the cortisol stress response pathway in a psychosocial stress induction (Trier Social Stress Test; TSST) with obese individuals and normal-weight controls.

METHOD

32 obese individuals (17 females; mean age = 33.94 years, SD = 11.31 years) and 32 normal-weight controls (17 females; mean age = 29.09 years, SD = 10.46 years) underwent the TSST. The salivary cortisol responses and three appraisal questionnaires (Primary Appraisal Secondary Appraisal, Visual Analogue Scale, Trier Inventory for Chronic Stress) were measured.

RESULTS

After stress induction, there was a significant main group difference between the obese individuals and the normal-weight controls for cortisol, with lower baseline and post-stress cortisol levels in the obese individuals. Nevertheless, the obese individuals as well as the normal-weight controls showed no significant difference in the self-reported assessment of the stress condition but some significant differences in the cognitive appraisal of the TSST.

CONCLUSION

In conclusion, the induction of psychosocial stress showed differences in the cortisol patterns between the obese individuals and the normal-weight controls. Furthermore, the present data suggest that obesity leads to lower cortisol activity, which may indicate alterations in the Hypothalamic-pituitary-adrencortical (HPA) axis.

HPA Axis Interactions with Behavioral Systems

Perhaps the most salient behaviors that individuals engage in involve the avoidance of aversive experiences and the pursuit of pleasurable experiences. Engagement in these behaviors is regulated to a significant extent by an individual's hormonal milieu. For example, glucocorticoid hormones are produced by the hypothalamic-pituitary-adrenocortical (HPA) axis, and influence most aspects of behavior. In turn, many behaviors can influence HPA axis activity. These bidirectional interactions not only coordinate an individual's physiological and behavioral states to each other, but can also tune them to environmental conditions thereby optimizing survival. The present review details the influence of the HPA axis on many types of behavior, including appetitively-motivated behaviors (e.g., food intake and drug use), aversively-motivated behaviors (e.g., anxiety-related and depressive-like) and cognitive behaviors (e.g., learning and memory). Conversely, the manuscript also describes how engaging in various behaviors influences HPA axis activity. Our current understanding of the neuronal and/or hormonal mechanisms that underlie these interactions is also summarized. © 2016 American Physiological Society. Compr Physiol 6:1897-1934, 2016.

Associations of smoking with overall obesity, and central obesity: a cross-sectional study from the Korea National Health and Nutrition Examination Survey (2010-2013)

OBJECTIVES

The association between smoking and obesity is a significant public health concern. Both are preventable risk factors of cardiovascular disease and a range of other conditions. However, despite numerous previous studies, no consensus has emerged regarding the effect of smoking on obesity. We therefore carried out a novel study evaluating the relationship between smoking and obesity.

METHODS

A total of 5,254 subjects aged 19 years or older drawn from the 2010-2013 Korea National Health and Nutrition Examination Survey were included in this cross-sectional study. Smoking was examined both in terms of smoking status and the quantity of cigarettes smoked by current smokers. Multiple logistic regression analysis was used to assess the association between smoking and obesity. Overall obesity was defined as a body mass index (BMI) ≥25 kg/m(2), and central obesity was defined as a waist circumference ≥90 cm for males and ≥85 cm for females. We adjusted for the possible confounding effects of age, sex, physical activity, alcohol consumption, and the presence of hypertension or diabetes.

RESULTS

A statistically significant difference in central obesity according to smoking status was identified. Current smokers were more likely to be centrally obese than never-smokers (adjusted odds ratio,1.30; 95% confidence interval, 1.02 to 1.67). However, no significant association was found between smoking and obesity defined by BMI. Moreover, among current smokers, no statistically significant association was found between the daily amount of smoking and obesity or central obesity.

CONCLUSIONS

Smoking was positively associated with central obesity. Current smokers should be acquainted that they may be more prone to central obesity.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

Clinical Manifestations Associated with Overweight/Obesity in Puerto Ricans with Fibromyalgia Syndrome

Objective. To determine the clinical manifestations associated with overweight/obesity in Hispanics from Puerto Rico with fibromyalgia syndrome (FMS). Methods. A cross-sectional study was performed in 144 patients with FMS (per American College of Rheumatology (ACR) classification criteria). Sociodemographic features, FMS-related symptoms, tender points (per ACR criteria), comorbidities, and FMS treatment were examined. BMI was calculated and patients were grouped into two categories: BMI ≤ 24.9 kg/m(2) (nonoverweight/obese) and BMI ≥ 25 kg/m(2) (overweight/obese). Bivariate and multivariate analyses were used to evaluate differences between the study groups. Results. The mean (standard deviation (SD)) age of patients was 50.2 (9.9) years; 95.1% were females and 75.7% were overweight/obese. In the bivariate analysis, overweight/obese patients were more likely to have self-reported memory impairment, anxiety, shortness of breath, and urinary frequency than nonoverweight/obese patients. In addition, the tender point count was higher in the overweight/obese group. In the logistic regression analyses, self-reported memory impairment and urinary frequency differences remained significant after adjusting for confounding variables. Conclusion. In this population of Puerto Ricans with FMS, overweight/obese patients experienced more FMS-related manifestations than nonoverweight/obese individuals. However, prospective studies are needed to confirm these associations and to elucidate if weight reduction interventions could favorably impact the severity of FMS.

Phosphodiesterase Type 5 Inhibitor and Erectile Dysfunction in Lower Urinary Tract Symptoms

Benign prostatic hyperplasia (BPH) is one of the most common diseases in older men and mostly induces lower urinary tract symptoms (LUTS). Multiple studies have shown that BPH inducing LUTS are intensely correlated with erectile dysfunction (ED) and that severity of LUTS was proportional to ED severity. Although a direct causal relationship has not been clarified, a tentative pathophysiology has been suggested to interpret the relationship between two disorders. Androgen plays an important role in the maintenance of the functional and structural integrity of the lower urinary tract and penis. Low testosterone, especially free testosterone, worsened detrusor overactivity and replacement of testosterone improved LUTS in the hypogonadal BPH patients. Nitric oxide synthase and nitric oxide are decreased in the transition zone of the hyperplastic prostate but phosphodiesterase types 4, 5, 11 are prominent in transition zone of hyperplastic prostate. Phosphodiesterase type 5 (PDE5) inhibitor with a long half-life could obtain the desired effect; therefore, tadalafil and undenafil frequently have been used to evaluate the effects in the two disorders. In clinical trials, tadalafil showed improvement of BPH-induced LUTS, but few of the studies showed a significant improvement on uroflowmetry. PDE5 inhibitors increase the concentration of cyclic guanosine monophosphate (cGMP) in plasma and smooth muscle, promoting erection of the penis, as well as relaxation of the bladder neck and prostate, leading to natural voiding. Sexual function and LUTS should be assessed and discussed with the patient when choosing the appropriate strategy and the patient's response to treatment should also be evaluated at the same time.

Steroidogenesis-adrenal cell signal transduction

The purpose of this article is to review fundamentals in adrenal gland histophysiology. Key findings regarding the important signaling pathways involved in the regulation of steroidogenesis and adrenal growth are summarized. We illustrate how adrenal gland morphology and function are deeply interconnected in which novel signaling pathways (Wnt, Sonic hedgehog, Notch, β-catenin) or ionic channels are required for their integrity. Emphasis is given to exploring the mechanisms and challenges underlying the regulation of proliferation, growth, and functionality. Also addressed is the fact that while it is now well-accepted that steroidogenesis results from an enzymatic shuttle between mitochondria and endoplasmic reticulum, key questions still remain on the various aspects related to cellular uptake and delivery of free cholesterol. The significant progress achieved over the past decade regarding the precise molecular mechanisms by which the two main regulators of adrenal cortex, adrenocorticotropin hormone (ACTH) and angiotensin II act on their receptors is reviewed, including structure-activity relationships and their potential applications. Particular attention has been given to crucial second messengers and how various kinases, phosphatases, and cytoskeleton-associated proteins interact to ensure homeostasis and/or meet physiological demands. References to animal studies are also made in an attempt to unravel associated clinical conditions. Many of the aspects addressed in this article still represent a challenge for future studies, their outcome aimed at providing evidence that the adrenal gland, through its steroid hormones, occupies a central position in many situations where homeostasis is disrupted, thus highlighting the relevance of exploring and understanding how this key organ is regulated. © 2014 American Physiological Society. Compr Physiol 4:889-964, 2014.

Circadian Clocks and the Interaction between Stress Axis and Adipose Function

Many physiological processes and most endocrine functions show fluctuations over the course of the day. These so-called circadian rhythms are governed by an endogenous network of cellular clocks and serve as an adaptation to daily and, thus, predictable changes in the organism's environment. Circadian clocks have been described in several tissues of the stress axis and in adipose cells where they regulate the rhythmic and stimulated release of stress hormones, such as glucocorticoids, and various adipokine factors. Recent work suggests that both adipose and stress axis clock systems reciprocally influence each other and adrenal-adipose rhythms may be key players in the development and therapy of metabolic disorders. In this review, we summarize our current understanding of adrenal and adipose tissue rhythms and clocks and how they might interact to regulate energy homoeostasis and stress responses under physiological conditions. Potential chronotherapeutic strategies for the treatment of metabolic and stress disorders are discussed.

Metabolic syndrome and lower urinary tract symptoms

Recently, clinical and epidemiologic data indicating the involvement of metabolic syndrome (MetS) in the pathogenesis and progression of lower urinary tract symptom (LUTS)/benign prostatic hyperplasia (BPH) are reported. This review evaluates the reports on the influence of MetS in the development and progression of LUTS/BPH, and discusses possible clinical implications for the management and treatment of this disease. Recent studies on the epidemiological relationship between MetS and LUTS hypothesize that MetS may be associated with an overactivity of the autonomic nervous system for which hyperinsulinemia, a key element of the MetS, might be responsible. An alternative explanation is that LUTS are associated with chronic ischemia of pelvis resulting from atherosclerotic changes in blood vessels, which leads the production of reactive oxygen species, which can damage the bladder detrusor. Control of autonomic nervous system overactivity and control of chronic bladder ischemia have potential as new targets for LUTS treatment. Studies suggest an association of MetS with LUTS/BPH, although further research is needed to understand how MetS influences LUTS/BPH. MetS should be considered a new domain in basic and clinical research in patients with LUTS/BPH and as a target for treatment.

Controversies about a common etiology for eating and mood disorders

Obesity and depression represent a growing health concern worldwide. For many years, basic science and medicine have considered obesity as a metabolic illness, while depression was classified a psychiatric disorder. Despite accumulating evidence suggesting that obesity and depression may share commonalities, the causal link between eating and mood disorders remains to be fully understood. This etiology is highly complex, consisting of multiple environmental and genetic risk factors that interact with each other. In this review, we sought to summarize the preclinical and clinical evidence supporting a common etiology for eating and mood disorders, with a particular emphasis on signaling pathways involved in the maintenance of energy balance and mood stability, among which orexigenic and anorexigenic neuropeptides, metabolic factors, stress responsive hormones, cytokines, and neurotrophic factors.

Eating behavior and stress: a pathway to obesity

Stress causes or contributes to a huge variety of diseases and disorders. Recent evidence suggests obesity and other eating-related disorders may be among these. Immediately after a stressful event is experienced, there is a corticotropin-releasing-hormone (CRH)-mediated suppression of food intake. This diverts the body’s resources away from the less pressing need to find and consume food, prioritizing fight, flight, or withdrawal behaviors so the stressful event can be dealt with. In the hours following this, however, there is a glucocorticoid-mediated stimulation of hunger and eating behavior. In the case of an acute stress that requires a physical response, such as a predator-prey interaction, this hypothalamic-pituitary-adrenal (HPA) axis modulation of food intake allows the stressful event to be dealt with and the energy used to be replaced afterward. In the case of ongoing psychological stress, however, chronically elevated glucocorticoids can lead to chronically stimulated eating behavior and excessive weight gain. In particular, stress can enhance the propensity to eat high calorie “palatable” food via its interaction with central reward pathways. Activation of this circuitry can also interact with the HPA axis to suppress its further activation, meaning not only can stress encourage eating behavior, but eating can suppress the HPA axis and the feeling of stress. In this review we will explore the theme of eating behavior and stress and how these can modulate one another. We will address the interactions between the HPA axis and eating, introducing a potential integrative role for the orexigenic hormone, ghrelin. We will also examine early life and epigenetic modulation of the HPA axis and how this can influence eating behavior. Finally, we will investigate the clinical implications of changes to HPA axis function and how this may be contributing to obesity in our society.

β-Cell adaptation in a mouse model of glucocorticoid-induced metabolic syndrome

Glucocorticoids (GCs) are stress hormones primarily responsible for mobilizing glucose to the circulation. Due to this effect, insulin resistance and glucose intolerance are concerns in patients with endogenous overproduction of GCs and in patients prescribed GC-based therapy. In addition, hypercortisolemic conditions share many characteristics with the metabolic syndrome. This study reports on a thorough characterization, in terms of glucose control and lipid handling, of a mouse model where corticosterone is given via the drinking water. C57BL/6J mice were treated with corticosterone (100 or 25 μg/ml) or vehicle in their drinking water for 5 weeks after which they were subjected to insulin or glucose tolerance tests. GC-treated mice displayed increased food intake, body weight gain, and central fat deposit accumulations. In addition, the GC treatment led to dyslipidemia as well as accumulation of ectopic fat in the liver and skeletal muscle, having a substantial negative effect on insulin sensitivity. Also glucose intolerance and hypertension, both part of the metabolic syndrome, were evident in the GC-treated mice. However, the observed effects of corticosterone were reversed after drug removal. Furthermore, this study reveals insights into β-cell adaptation to the GC-induced insulin resistance. Increased pancreatic islet volume due to cell proliferation, increased insulin secretion capacity, and increased islet chaperone expression were found in GC-treated animals. This model mimics the human metabolic syndrome. It could be a valuable model for studying the complex mechanisms behind the development of the metabolic syndrome and type 2 diabetes, as well as the multifaceted relations between GC excess and disease.

Influence of physical activity and nutrition on obesity-related immune function

Research examining immune function during obesity suggests that excessive adiposity is linked to impaired immune responses leading to pathology. The deleterious effects of obesity on immunity have been associated with the systemic proinflammatory profile generated by the secretory molecules derived from adipose cells. These include inflammatory peptides, such as TNF- α , CRP, and IL-6. Consequently, obesity is now characterized as a state of chronic low-grade systemic inflammation, a condition considerably linked to the development of comorbidity. Given the critical role of adipose tissue in the inflammatory process, especially in obese individuals, it becomes an important clinical objective to identify lifestyle factors that may affect the obesity-immune system relationship. For instance, stress, physical activity, and nutrition have each shown to be a significant lifestyle factor influencing the inflammatory profile associated with the state of obesity. Therefore, the purpose of this review is to comprehensively evaluate the impact of lifestyle factors, in particular psychological stress, physical activity, and nutrition, on obesity-related immune function with specific focus on inflammation.

Age-dependent and gender-dependent regulation of hypothalamic-adrenocorticotropic-adrenal axis

Tightly regulated output of glucocorticoids is critical to maintaining immune competence, the structure of neurons, muscle, and bone, blood pressure, glucose homeostasis, work capacity, and vitality in the human and experimental animal. Age, sex steroids, gender, stress, body composition, and disease govern glucocorticoid availability through incompletely understood mechanisms. According to an ensemble concept of neuroendocrine regulation, successful stress adaptations require repeated incremental signaling adjustments among hypothalamic corticotropin-releasing hormone and arginine vasopressin, pituitary adrenocorticotropic hormone, and adrenal corticosteroids. Signals are transduced via (positive) feedforward and (negative) feedback effects. Age and gonadal steroids strongly modulate stress-adaptive glucocorticoid secretion by such interlinked pathways.

High-end normal adrenocorticotropic hormone and cortisol levels are associated with specific cardiovascular risk factors in pediatric obesity: a cross-sectional study

BACKGROUND

The hypothalamic-pituitary-adrenal (HPA) axis, and in particular cortisol, has been reported to be involved in obesity-associated metabolic disturbances in adults and in selected populations of adolescents. The aim of this study was to investigate the association between morning adrenocorticotropic hormone (ACTH) and cortisol levels and cardiovascular risk factors in overweight or obese Caucasian children and adolescents.

METHODS

This cross-sectional study of 450 obese children and adolescents (aged 4 to 18 years) was performed in a tertiary referral center. ACTH, cortisol, cardiovascular risk factors (fasting and post-challenge glucose, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglycerides, and hypertension) and insulin resistance were evaluated. All analyses were corrected for confounding factors (sex, age, puberty, body mass index), and odds ratios were determined.

RESULTS

ACTH and cortisol levels were positively associated with systolic and diastolic blood pressure, triglycerides, fasting glucose and insulin resistance. Cortisol, but not ACTH, was also positively associated with LDL-cholesterol. When adjusted for confounding factors, an association between ACTH and 2 h post-oral glucose tolerance test glucose was revealed. After stratification according to cardiovascular risk factors and adjustment for possible confounding factors, ACTH levels were significantly higher in subjects with triglycerides ≥90th percentile (P <0.02) and impaired fasting glucose or glucose tolerance (P <0.001). Higher cortisol levels were found in subjects with blood pressure ≥95th percentile and LDL-cholesterol ≥90th percentile. Overall, the highest tertiles of ACTH (>5.92 pmol/l) and cortisol (>383.5 nmol/l) although within the normal range were associated with increases in cardiovascular risk factors in this population.

CONCLUSIONS

In obese children and adolescents, high morning ACTH and cortisol levels are associated with cardiovascular risk factors. High ACTH levels are associated with high triglyceride levels and hyperglycemia, while high cortisol is associated with hypertension and high LDL-cholesterol. These specific relationships suggest complex mechanisms through which the HPA axis may contribute to metabolic impairments in obesity, and merit further investigations.

Decreased muscle concentrations of ATP and PCR in the quadriceps muscle of fibromyalgia patients--a 31P-MRS study

BACKGROUND AND METHODS

Fibromyalgia (FMS) has a prevalence of approximately 2% in the population. Central alterations have been described in FMS, but there is not consensus with respect to the role of peripheral factors for the maintenance of FMS. 31P magnetic resonance spectroscopy (31P-MRS) has been used to investigate the metabolism of phosphagens in muscles of FMS patients, but the results in the literature are not in consensus. The aim was to investigate the quantitative content of phosphagens and pH in resting quadriceps muscle of patients with FMS (n = 19) and in healthy controls (CONTROLS; n = 14) using (31) P-MRS. It was also investigated whether the concentrations of these substances correlated with measures of pain and/or physical capacity.

RESULTS

Significantly lower concentrations of adenosine triphosphate (ATP) and phosphocreatinine (PCr; 28-29% lower) were found in FMS. No significant group differences existed with respect to inorganic phosphate (Pi), Pi/PCr and pH. The quadriceps muscle fat content was significantly higher in FMS than in CONTROLS [FMS: 9.0 ± 0.5% vs.

CONTROLS

6.6 ± 0.6%; (mean ± standard error); P = 0.005]. FMS had significantly lower hand and leg capacity according to specific physical test, but there were no group differences in body mass index, subjective activity level and in aerobic fitness. In FMS, the specific physical capacity in the leg and the hand correlated positively with the concentrations of ATP and PCr; no significant correlations were found with pain intensities.

CONCLUSIONS

Alterations in intramuscular ATP, PCr and fat content in FMS probably reflect a combination of inactivity related to pain and dysfunction of muscle mitochondria.

GH improves spatial memory and reverses certain anabolic androgenic steroid-induced effects in intact rats

GH has previously been shown to promote cognitive functions in GH-deficient rodents. In this study we report the effects of GH on learning and memory in intact rats pretreated with the anabolic androgenic steroid nandrolone. Male Wistar rats received nandrolone decanoate (15 mg/kg) or peanut oil every third day for 3 weeks and were subsequently treated with recombinant human GH (1.0 IU/kg) or saline for 10 consecutive days. During the GH/saline treatment spatial learning and memory were tested in the Morris water maze (MWM). Also, plasma levels of IGF1 were assessed and the gene expression of the GH receptors (Ghr), Igf1 and Igf2, in hippocampus and frontal cortex was analyzed. The results demonstrated a significant positive effect of GH on memory functions and increased gene expression of Igf1 in the hippocampus was found in the animals treated with GH. In addition, GH was demonstrated to increase the body weight gain and was able to attenuate the reduced body weight seen in nandrolone-treated animals. In general, the rats treated with nandrolone alone did not exhibit any pronounced alteration in memory compared with controls in the MWM, and in many cases GH did not induce any alteration. Regarding target zone crossings, considered to be associated with spatial memory, the difference between GH- and steroid-treated animals was significant and administration of GH improved this parameter in the latter group. In conclusion, GH improves spatial memory in intact rats and can reverse certain effects induced by anabolic androgenic steroid.

Antipsychotic-induced metabolic and cardiovascular side effects in schizophrenia: a novel mechanistic hypothesis

The use of antipsychotics is hindered by the frequent occurrence of metabolic and cardiovascular side effects, resulting in worsened quality of life and greater mortality as a result of cardiovascular and cerebrovascular disorders in schizophrenia patients than the comparable general population. The various antipsychotics induce extrapyramidal symptoms, impaired glucose and lipid metabolism, weight gain, hypertension and arrhythmias, with variable frequency. Second-generation antipsychotics appear to have several advantages over first-generation antipsychotics, including a claimed better action on cognitive function and the negative symptoms of schizophrenia, and lower frequency of extrapyramidal side effects; however, their use is associated with a greater frequency of metabolic and cardiovascular disturbances. The mechanisms of these important side effects are not well understood, and generic approaches (psychoeducational programmes and symptomatic therapies) have been proposed to limit their severity. Extensive data from the literature indicate that autonomic nervous system dysfunction--intrinsic to schizophrenia and strongly exacerbated by antipsychotic treatment--is the cause of the pervasive metabolic and vascular dysfunctions associated with schizophrenia. In this article, we marshal further literature data to argue that the metabolic and cardiovascular side effects of antipsychotics are primarily mediated by their ability to block peripheral dopamine receptors, which physiologically modulate sympathetic activity. We also propose that these effects might be overcome by providing peripheral dopaminergic stimulation.

Glucocorticoids and type 2 diabetes: from physiology to pathology

Type 2 diabetes mellitus is the result of interaction between genetic and environmental factors, leading to heterogeneous and progressive pancreatic β-cell dysfunction. Overweight and obesity are major contributors to the development of insulin resistance and impaired glucose tolerance. The inability of β cells to secrete enough insulin produces type 2 diabetes. Abnormalities in other hormones such as reduced secretion of the incretin glucagon-like peptide 1 (GLP-1), hyperglucagonemia, and raised concentrations of other counterregulatory hormones also contribute to insulin resistance, reduced insulin secretion, and hyperglycaemia in type 2 diabetes. Clinical-overt and experimental cortisol excess is associated with profound metabolic disturbances of intermediate metabolism resulting in abdominal obesity, insulin resistance, and low HDL-cholesterol levels, which can lead to diabetes. It was therefore suggested that subtle abnormalities in cortisol secretion and action are one of the missing links between insulin resistance and other features of the metabolic syndrome. The aim of this paper is to address the role of glucocorticoids on glucose homeostasis and to explain the relationship between hypercortisolism and type 2 diabetes.