Hypothalamic-pituitary-adrenal Axis Function Research Articles

Hypothalamic-Pituitary-Adrenal axis dysfunction by early life stress

Evidence indicates that early life stress (ELS) may act as a risk factor for the development and maintenance of adulthood severe mental health disorders due to persistent dysregulation within the hypothalamic–pituitary-adrenal (HPA) axis. It is now broadly accepted that psychological stress may change the internal homeostatic state of an individual. The dysregulation seems to be a byproduct of changes noted in the HPA axis hormone’s ability to bind to the glucocorticoid and mineralocorticoid receptors, crucial in maintaining homeostasis. Whenever there is an acute interruption of this balance, illness may result. The social and physical environments have an enormous impact on our physiology and behavior, and they influence the process of adaptation or ‘allostasis’. The HPA axis response to stress can be thought of as a mirror of the organism's response to stress: acute responses are generally adaptive, but excessive or prolonged responses can lead to deleterious effects. Evidence indicates that early-life stress can induce persistent changes in the ability of the HPA axis to respond to stress in adulthood This review aims to examine and summarise the existing literature exploring the relationship between ELS with regards specifically to HPA axis functioning. The maintenance of the internal homeostatic state of an individual is proposed to be based on the ability of circulating glucocorticoids to exert negative feedback on the secretion of HPA hormones through binding to mineralocorticoid (MR) and glucocorticoid (GR) receptors limiting the vulnerability to diseases related to psychological stress in genetically predisposed individuals.

Contribution of Growth Arrest-Specific 5/miR-674 to the Hypothalamus Pituitary Adrenal Axis Regulation Effect by Electroacupuncture following Trauma

Background: Electroacupuncture (EA) can improve trauma-induced hypothalamus pituitary adrenal axis (HPA) hyperactivity. However, the mechanism underlying the EA effect has not been fully understood. Methods and Study Design: This study was undertaken to explore the role of hypothalamic growth arrest-specific 5 (Gas5) in the regulation of EA on HPA axis function post-surgery. Paraventricular nuclear Gas5 levels were upregulated in rats using an intracerebroventricular injection of pAAV-Gas5. Primary hypothalamic neurons and 293T cells were cultured for miRNA and siRNAs detection. Radioimmunoassay, PCR, Western blot, and immunohistochemistry were used for HPA axis function evaluation. Results: The overexpression of Gas5 abolished the effect of EA on the regulation of trauma-induced HPA axis hyperactivity. Using a bioinformatics analysis and dual luciferase assay, we determined that miRNA-674 was a target of Gas5. Additionally, miRNA-674 levels were found to have decreased in trauma rats, and this effect was reversed after EA intervention. TargetScan analysis showed that serum and glucocorticoid inducible kinase 1 (SGK1) were targets of miR-674. Moreover, we found that SGK1 protein levels increased in trauma rats and SGK1 expression inhibition alleviated HPA axis abnormality post-surgery. EA could improve the number of hypothalamus iba-1 positive cells and hypothalamic interleukin 1 beta protein expression. Conclusions: Our study demonstrated the involvement of the hypothalamic Gas5/miRNA-674/SGK1 signaling pathway in EA regulation of HPA axis function after trauma.

The Cortisol and ACTH Response to Dex/CRH Testing in Women With and Without Perimenopausal Depression.

Abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis are frequent accompaniments of depression, and studies have documented the role of stress and stressful life events in the ontogeny of perimenopausal depressions (PMD). Because HPA axis function in women is further modulated both by aging and ovarian steroids, it is possible that a dysregulated HPA axis contributes to the increased risk of PMD. We examined HPA axis function in perimenopausal women with and without depression using the combined dexamethasone-corticotropin-releasing hormone (Dex/CRH) test. Dex/CRH tests were performed on 20 women with PMD and 20 women who were also perimenopausal but without current or past depression (control women). Main outcome measures were plasma levels of cortisol and adrenocorticotropin (ACTH) and 24-hour urinary free cortisol (UFC). Five women took chronic stable medications, otherwise all women were medically healthy, and both groups were comparable with respect to reproductive stage and age. Standardized symptom rating scales were administered to each woman prior to Dex/CRH testing. No group differences were present in either baseline or stimulated ACTH and cortisol secretion. Baseline plasma measures of estradiol, progesterone, and 24-hour UFC levels similarly did not differ in PMD and control women. Despite reports of increased stress responsiveness in PMD, we observed no abnormalities of HPA axis activity associated with PMD compared with women without depression. These findings suggest that PMD is not uniformly associated with HPA dysregulation and could reflect underlying pathophysiologic processes that are distinct from women with nonreproductive-related depressions.

Twelve patients with mental illness who complained of postprandial symptoms in addition to fatigue showed central adrenal insufficiency

BackgroundAdrenal insufficiency (AI) may cause psychiatric symptoms. We evaluated the correlation between the hypothalamic-pituitary-adrenal axis (HPA) function in patients with mental illness who complained of postprandial symptoms in addition to fatigue. MethodsWe recruited 16 patients with mental illness who complained of postprandial symptoms in addition to fatigue for the evaluation of the HPA axis function using a rapid adrenocorticotropin (ACTH) test with Cortrosyn®, (250 μg), a corticotropin-releasing hormone (CRH) test, and an insulin tolerance test (ITT). The ITT results were adopted if the nadir blood glucose level was <2.2 mm/L. Patients with showed a peak cortisol level of <496.6 nmol/L (18 μg/dL) in the ITT were diagnosed with AI and the results were compared with the results of the rapid ACTH and CRH tests. The patients’ clinical characteristics were evaluated. ResultsTwelve of 16 patients met the criteria for the adoption of the ITT. A peak cortisol level of <496.6 nmol/L was detected by the rapid ACTH test in three patients, by the CRH test in ten patients, and by the ITT in all twelve patients. Six of the above 12 patients used exogenous steroids due to the comorbidities such as bronchial asthma. ConclusionsTwelve of the patients who complained of postprandial symptoms in addition to fatigue met the diagnostic criteria for AI. AI is often latent and more frequent in patients with mental illness. It is therefore necessary to inquire about exogenous steroid use for comorbidities when managing such patients.

The role of maternal nutrition during pregnancy in the intergenerational transmission of childhood adversity

Adverse childhood experiences (ACEs) of a woman can lead to dysregulated hypothalamus-pituitary-adrenal (HPA) axis during pregnancy, which can in turn adversely affect her offspring HPA axis function. Choline and docosahexaenoic acid (DHA) are dietary factors with the potential to favorably modify the stress response system. The current study aimed to investigate whether maternal choline intake and DHA status moderate the effects of maternal ACEs exposure on maternal and infant HPA axes function. Participants were a sub-sample of the prospective longitudinal Alberta Pregnancy Outcomes and Nutrition (APrON) study consisting of 340 mothers and 238 infants. We collected data on maternal ACEs, maternal choline intake (24-hour dietary recall) and serum phospholipid DHA concentrations (at each trimester). Women self-collected saliva samples on two consecutive days (at waking, +30 min, 1100 h, and 2100 h) in each trimester to calculate the cortisol awakening response (CAR) and total daytime cortisol. Infants’ salivary cortisol was measured before and after (20, and 40 min) exposure to a blood draw stressor 3 months postpartum. During pregnancy, choline intake moderated (reduced) the association between maternal ACEs and CAR (β = −0.003; 95% CI −0.006, −0.003), but not total daytime cortisol. DHA status did not moderate the association between ACEs and CAR or total daytime cortisol. Choline intake also moderated (reduced) the association between maternal CAR and infant cortisol during a stress task (β = −0.0001; 95% CI −0.0002, −0.00003). Maternal DHA status revealed no modifying effects on these associations. Our findings suggest that maternal choline intake, but not DHA status, can buffer the associations between ACEs and maternal HPA axis, as well as maternal and infant HPA axes function.

Lack of Evidence for a Relationship Between the Hypothalamus-Pituitary-Adrenal and the Hypothalamus-Pituitary-Thyroid Axis in Adolescent Depression.

In adults with major depressive disorder (MDD), a dysfunction between the hypothalamus-pituitary-adrenal (HPA) and the hypothalamus-pituitary-thyroid (HPT) axis has been shown, but the interaction of both axes has not yet been studied in adolescent major depressive disorder (MDD). Data from 273 adolescents diagnosed with MDD from two single center cross-sectional studies were used for analysis. Serum levels of thyrotropin (TSH), free levothyroxine (fT4), and cortisol were determined as indicators of basal HPT and HPA axis functioning and compared to that of adolescent controls by t-tests. Quantile regression was employed in the sample of adolescents with MDD to investigate the relationship between both axes in the normal as well as the pathological range of cortisol levels, considering confounders of both axes. In adolescent MDD, cortisol levels and TSH levels were significantly elevated in comparison to controls (p = <.001, d = 1.35, large effect size, and p = <.001, d = 0.79, moderate effect size, respectively). There was a positive linear relationship between TSH and cortisol (p = .003, d = 0.25, small effect size) at the median of cortisol levels (50th percentile). However, no relationship between TSH and cortisol was found in hypercortisolemia (cortisol levels at the 97.5th percentile). These findings imply that HPT and HPA axis dysfunction is common in adolescents with MDD and that function of both axes is only loosely related. Moreover, the regulation of the HPA and HPT axis are likely subjected to age-related maturational adjustments since findings of this study differ from those reported in adults.

A Life Course Approach to the Relationship Between Fetal Growth and Hypothalamic-Pituitary-Adrenal Axis Function.

Human and animal studies suggest that hypothalamic-pituitary-adrenal axis (HPA-A) function may be programmed in utero; however, these findings are inconsistent. Given the powerful metabolic actions of cortisol, it is important to clarify the influence of early life on adult HPA-A function. To determine the relationship between fetal growth and HPA-A stress response to a psychosocial stressor in young adults. Multigenerational, prospective cohort study (the Raine Study) conducted between 1989 and 1991. King Edward Memorial Hospital, Perth, Western Australia, Australia. A total of 917 participants aged 18 years from Gen2 of the Raine Study. Measures of hypothalamic-pituitary-adrenal axis function before and after exposure to the Trier Social Stress Test. In fully adjusted models, an inverse linear relationship was observed between birthweight and plasma measures of (1) baseline cortisol (β = -0.90%, 95% CI: -1.73 to -0.07; P = 0.03); (2) peak cortisol (β = -0.78%, 95% CI -1.51 to -0.06; P = 0.03); (3) area under the curve with respect to ground (β = -0.89%, 95% CI -1.60 to -0.18; P = 0.01); and (4) adrenal sensitivity (β = -1.02, 95% CI: -1.85 to -0.18; P = 0.02). Similar results were demonstrated for percent optimal birthweight. No consistent quadratic relationships were identified. No associations were found between measures of fetal adiposity and HPA-A function at age 18 years, or fetal growth and HPA-A response pattern. Removal of anticipatory responders from the models substantially attenuated the observed relationships. We observed an inverse linear relationship between fetal growth and HPA-A function at age 18 years. This differs from the inverse parabolic relationship (inverted U curve) reported in adults of advanced age. Altered adrenal sensitivity may underlie this relationship.

DNA methylation in former extremely low birth weight newborns: association with cardiovascular and endocrine function.

Background:There is increased risk of cardiovascular, metabolic and hypertensive disorders in later life in the preterm population. We studied school-age children who had been born extremely premature who had undergone endocrine, cardiovascular and anthropometric evaluations.Methods:School age measurements of salivary cortisol, adrenal androgens, blood pressure and anthropometric markers were correlated with DNA methylation of 11-beta hydroxysteroid dehydrogenase type 2 (11BHSD2), leptin, and the LINE1 repetitive DNA element.Results:We observed a modest correlation between logAUC for salivary cortisol and methylation of leptin in preterm infants and a negative correlation between methylation of region 1 of the glucocorticoid receptor in term-born infants. There was an association between LINE1 methylation and cortisol response to awakening and a negative correlation between LINE1 and systolic blood pressure at 6-7 years. Methylation of the GR promoter region showed a positive association with systolic blood pressure at 6-7 years of age.Conclusions:These results show that extremely preterm birth, followed by complex patterns of endocrine, cardiovascular and metabolic exposures during early postnatal life, is associated with lasting changes in DNA methylation patterns in genes involved in hypothalamic pituitary adrenal axis function, adrenal hormonal regulation and cardiometabolic risk.

Age and Parity Effects in the Hypothalamic Pituitary Adrenal Axis’ Response to Multimodal Stress in Female Mice

The hypothalamic pituitary adrenal (HPA) axis responds to environmental perturbations to maintain homeostasis. Pregnancy demands extensive modifications in HPA axis function to prepare for increased energy and metabolic demands required to meet the needs of mother and offspring. Short-term effects of pregnancy on the HPA axis have been shown, but data is lacking regarding the long-term effects in middle-aged female mice no longer breeding. Since changes of the HPA axis are further found with age, in this study, we examined both parity- and age-related interactions on the HPA axis in female mice. Wildtype C57bl/6N females were divided into nulliparous young (NY) (3-6 mo) and nulliparous middle-aged (NM) or multiparous retired-breeder middle-aged (RBM) (8-10 mo) groups. RBM mice were killed at least 4 weeks after their last litter was weaned. Control mice were euthanized directly out of the home cage and experimental groups were euthanized at 0 min, 30 min, or 90 min recovery (n=8-10/ group) after 2h of multi-modal stress (MMS; restraint, noise, shaker, light). (Paraventricular nucleus of the hypothalamus (PVN) neuronal activity was quantified by c-FOS immunoreactivity (-ir), and plasma corticosterone (CORT) levels were measured by radioimmunoassay. Corticotropin releasing hormone (CRH) mRNA was assayed by in situ hybridization. Two-way ANOVA showed effects of age (p<0.0248), parity (p<0.0021), time (p<0.0001), and interaction (p<0.0009) on CORT levels. Specifically, basal CORT levels were reduced in NM/RBM versus NY mice. In all groups, CORT levels were significantly elevated by MMS. There was no difference between CORT levels immediately after MMS in NY or NM groups, but CORT levels after 30- and 90- min recovery from MMS remained elevated in NM, indicating reduced negative feedback with age. Additionally, RBM plasma CORT was further reduced in all time groups versus NM, accompanied by a return to baseline CORT after 90 min recovery, suggesting a parity-dependent effect on the HPA axis. Changes in CORT levels were correlated with c-FOS-ir. MMS increased PVN c-FOS-ir in all groups compared to controls and c-FOS-ir in NM was significantly greater than PVN c-FOS of RBM. Further, while c-FOS-ir in the NY females was reduced to baseline 30 min after MMS, the return to baseline was more gradual in NM. No effect of parity or age was seen in Crh mRNA. Collectively, our findings show that activation of the HPA axis in females involves interactions between age- and parity- dependent function. Our findings further show activation and inhibition of the HPA axis in females involving long-term changes that occur after pregnancy, which may increase risk for stress- or postpartum- related disorders. Supported by NIDDK 1-R01 DK105826

Predictive Accuracy of Delta Cortisol on Recovery of Adrenal Function in Patients With Drug Induced Cushing’s Syndrome With Secondary Adrenal Insufficiency

There is a growing concern upon the finding of many drug induced Cushing’s syndrome because of inadvertent use of glucocorticoids (GC) either prescribed or as alternative medicine in Myanmar. These patients are presenting with diversity of clinical problems ranging from hypertension, diabetes to acute adrenal crisis due to hypothalamic-pituitary-adrenal (HPA) axis suppression and secondary adrenal insufficiency (AI). The present study aimed to assess the delta cortisol (the degree of cortisol increments) during the first short Synacthen test (SST) as a factor predictive of adrenal function recovery in patients with drug induced Cushing’ syndrome with secondary AI and to determine the proportion of patients who recovered from AI within six-month follow-up. This was a hospital based prospective analytical study that enrolled a total of 52 patients with drug induced Cushing’s syndrome with secondary AI from January 2018 to June 2019. Secondary AI is defined by morning basal serum cortisol ≤ 400 nmol/L with Synacthen stimulated peak cortisol level ≤ 550 nmol/L and serum ACTH < 60 pg/ml. The follow-up SSTs were performed at three-month and six-month after first SST, and the patients with morning basal serum cortisol > 400 nmol/L (or) Synacthen stimulated peak serum cortisol > 550 nmol/L during follow-up SSTs are defined as recovered adrenal function group. In this study, a total of 52 patients were treated with modified regimen of physiological dose of prednisolone with tapering schedule or stress dose GC based on the basal serum cortisol levels up to six months. Among them, nearly half (n=25 / 48.1%) of the patients with drug induced Cushing’s syndrome with secondary AI achieved normal adrenal function within six-month follow-up. It was found that mean values for delta cortisol were not statistically significant between recovered and non-recovered groups, 118.6 nmol/L (SD 72.3) and 97.2 nmol/L (SD 64.2) respectively. The delta cortisol during the first SST could not predict strongly (AUC - 0.6, 95% CI - 0.44 to 0.76, P = 0.2) the recovery of adrenal function in patients with drug induced Cushing’s syndrome with secondary AI and it was inconsistent with previous studies. The older age of the patients, oral route of administration of drugs causing Cushing’s syndrome and comorbid hypertension were found to be more significant in the non-recovered group. In conclusion, the present study did not support the evidence that the delta cortisol during the first SST could predict adrenal function recovery in patients with drug induced Cushing’ syndrome with secondary AI. Reference: (1) Baek et al., 2016; Recovery of Adrenal Function in Patients with Glucocorticoids Induced Secondary AI. Endocrinol Metab.31, pp. 153–160. (2) Pofi et al., 2018; The Short Synacthen Test Can Be Used to Predict Recovery of HPA Axis Function. J Clin Endocrinol Metab.103(8), pp. 3050–3059.

Stress-induced cortisol response is associated with right amygdala volume in early childhood

Rodent research suggests that dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and the resulting cortisol stress response can alter the structure of the hippocampus and amygdala. Because early-life changes in brain structure can produce later functional impairment and potentially increase risk for psychiatric disorder, it is critical to understand the relationship between the cortisol stress response and brain structure in early childhood. However, no study to date has characterized the concurrent association between cortisol stress response and hippocampal and amygdala volume in young children. In the present study, 42 young children (Mage = 5.97, SD = 0.76), completed a frustration task and cortisol response to stress was measured. Children also underwent magnetic resonance imaging (MRI), providing structural scans from which their hippocampal and amygdala volumes were extracted. Greater cortisol stress response was associated with reduced right amygdala volume, controlling for whole brain volume, age, sex, and number of cortisol samples. There were no significant associations between cortisol stress response and bilateral hippocampus or left amygdala volumes. The association between right amygdala volume and cortisol stress response raises the non-mutually exclusive possibilities that the function of the HPA axis may shape amygdala structure and/or that amygdala structure may shape HPA axis function. As both cortisol stress response and amygdala volume have been associated with risk for psychopathology, it is possible that the relationship between cortisol stress response and amygdala volume is part of a broader pathway contributing to psychiatric risk.

Childhood Maltreatment and Its Interaction with Hypothalamic–Pituitary–Adrenal Axis Activity and the Remission Status of Major Depression: Effects on Functionality and Quality of Life

Relationships among childhood maltreatment (CM), hypothalamic-pituitary-adrenal (HPA) axis disturbances, major depressive disorder (MDD), poor functionality, and lower quality of life (QoL) in adulthood have been described. We aimed to study the roles of the remission status of depression and HPA axis function in the relationships between CM and functionality and QoL. Ninety-seven patients with MDD and 97 healthy controls were included. The cortisol awakening response, cortisol suppression ratio in the dexamethasone suppression test, and diurnal cortisol slope were assessed. Participants completed measures of psychopathology, CM, functionality, and QoL. Multiple linear regression analyses were performed to study the relationships between CM and functionality and QoL. Only non-remitted MDD patients showed lower functionality and QoL than controls, indicating that depressive symptoms may partly predict functionality and QoL. Cortisol measures did not differ between remitted and non-remitted patients. Although neither HPA axis measures nor depression remission status were consistently associated with functionality or QoL, these factors moderated the effects of CM on functionality and QoL. In conclusion, subtle neurobiological dysfunctions in stress-related systems could help to explain diminished functionality and QoL in individuals with CM and MDD and contribute to the persistence of these impairments even after the remission of depressive symptoms.

Poly (I:C)-induced maternal immune activation modifies ventral hippocampal regulation of stress reactivity: prevention by environmental enrichment

Environmental enrichment (EE) has been successfully implemented in human rehabilitation settings. However, the mechanisms underlying its success are not understood. Incorporating components of EE protocols into our animal models allows for the exploration of these mechanisms and their role in mitigation. Using a mouse model of maternal immune activation (MIA), the present study explored disruptions in social behavior and associated hypothalamic pituitary adrenal (HPA) axis functioning, and whether a supportive environment could prevent these effects. We show that prenatal immune activation of toll-like receptor 3, by the viral mimetic polyinosinic-polycytidylic acid (poly(I:C)), led to disrupted maternal care in that dams built poorer quality nests, an effect corrected by EE housing. Standard housed male and female MIA mice engaged in higher rates of repetitive rearing and had lower levels of social interaction, alongside sex-specific expression of several ventral hippocampal neural stress markers. Moreover, MIA males had delayed recovery of plasma corticosterone in response to a novel social encounter. Enrichment housing, likely mediated by improved maternal care, protected against these MIA-induced effects. We also evaluated c-Fos immunoreactivity associated with the novel social experience and found MIA to decrease neural activation in the dentate gyrus. Activation in the hypothalamus was blunted in EE housed animals, suggesting that the putative circuits modulating social behaviors may be different between standard and complex housing environments. These data demonstrate that augmentation of the environment supports parental care and offspring safety/security, which can offset effects of early health adversity by buffering HPA axis dysregulation. Our findings provide further evidence for the viability of EE interventions in maternal and pediatric settings.

Maternal behavior and the neonatal HPA axis in the Wistar Audiogenic Rat (WAR) strain: Early-life implications for a genetic animal model in epilepsy

Epileptogenesis is a multistage process and seizure susceptibility can be influenced by stress early in life. Wistar Audiogenic Rat (WAR) strain is an interesting model to study the association between stress and epilepsy, since it is naturally susceptible to seizures and present changes in the hypothalamus–pituitary–adrenal (HPA) axis activity. All these features are related to the pathogenic mechanisms usually associated with psychiatric comorbidities present in epilepsy. Therefore, the current study aimed to evaluate the neonate HPA axis function and maternal care under control and stress conditions in the WAR strain. Maternal behavior and neonate HPA axis were evaluated in Wistar and WAR strains under rest and after the presence of stressors. We observed that WAR pups present higher plasmatic corticosterone concentration as compared to Wistar pups. Although WAR dams do not show significant altered maternal behavior at rest, there is a higher latency to recover the litter in the pup retrieval test, while some did not recover all the litter. Wistar Audiogenic Rat dams presented similar behaviors to Wistar dams to a female intruder and maternal care with the pups in the maternal defense test. Taken together, these findings indicate that the WAR strain could show HPA axis disruption early in life and dams present altered maternal behavior under stressful events. Those alterations make the WAR strain an interesting model to evaluate vulnerability to epilepsy and its associated neuropsychiatric comorbidities.

Changes in hypothalamic-pituitary-adrenal axis activity related to the acquisition of a spatial task in the Barnes maze

It is well known that animals can learn escape responses when exposed to aversive stimuli. Additionally, it has been described that as effective behaviors to reduce contact with aversive stimuli are developed, the level of arousal decreases. However, the avoidance tasks, typically described, are based on the learning of simple motor patterns that do not allow a detailed description of the process of acquisition and refinement of the escape task. The present study aimed to describe the changes in the performance of animals that received one or two training sessions in the Barnes circular maze and the activity of the hypothalamic-pituitary-adrenal (HPA) axis as an indicator of the arousal associated with the learning of escape responses. Our findings showed that extended training results in lower HPA axis activity than standard training as reflected by corticosterone release and paraventricular hypothalamic nucleus activity. This result suggests that the HPA axis functioning may be associated with the predictability and control that animals acquire through the learning of a navigation route that allows them to escape from an aversive situation in spatial tasks.

Total glycosides from stems of Cistanche tubulosa alleviate depression-like behaviors: bidirectional interaction of the phytochemicals and gut microbiota

BackgroundAs the most frequently used kidney-yang tonifying herb in traditional Chinese medicine, dried succulent stems of Cistanche tubulosa (Schenk) Wight (CT) have been shown to be effective in the treatment of depression. However, the antidepressant components and their underlying mechanism remain unclear. PurposeTo explore the active components of CT against depression, as well as the potential mechanisms. Study design and methodsBehavioral despair tests were used to assess the antidepressant activities of polysaccharides, oligosaccharides and different glycoside-enriched fractions separated from CT, as well as the typical gut microbiota metabolites including 3-hydroxyphenylpropionic acid (3-HPP) and hydroxytyrosol (HT). Furthermore, the effects of bioactive fractions and metabolites on chronic unpredictable mild stress (CUMS) model were explored with multiple pharmacodynamics and biochemical analyses. Changes in colonic histology and the intestinal barrier were observed by staining and immunohistochemical analysis. Gut microbial features and tryptophan-kynurenine metabolism were explored using 16S rRNA sequencing and western-blotting, respectively. ResultsTotal glycosides (TG) dramatically alleviated depression-like behaviors compared to different separated fractions, reflecting in the synergistic effects of phenylethanoid and iridoid glycosides on the hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis, severe neuro- and peripheral inflammation, and deficiencies in 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor in the hippocampus. Moreover, TG mitigated low-grade inflammation in the colon and intestinal barrier disruption, and the abundances of several bacterial genera highly correlated with the HPA axis and inflammation in CUMS rats. Consistently, the expression of indoleamine 2, 3-dioxygenase 1 (IDO1) in the colon was significantly reduced after TG administration, accompanied by the suppression of tryptophan-kynurenine metabolism. On the other hand, HT also exerted a marked antidepressant effect by ameliorating HPA axis function, pro-inflammatory cytokine release, and tryptophan-kynurenine metabolism, while it was unable to largely adjust the disordered gut microbiota in the same manner as TG. Surprisingly, superior to fluoxetine, TG and HT could further improve dysfunction of the hypothalamic-pituitary-gonadal axis and abnormal cyclic nucleotide metabolism. ConclusionTG are primarily responsible for the antidepressant activity of CT; its effect might be achieved through the bidirectional interaction of the phytochemicals and gut microbiota, and reflect the advantage of CT in the treatment of depression.

Externalizing behavior and stress system functioning in infants exposed to early adversity: A multi-system exploration.

Children who experience early adversity often show alterations across multiple stress response systems, including the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS). Changes in the diurnal rhythm of salivary cortisol (a marker of HPA axis functioning) and alpha-amylase (a marker of ANS functioning) may increase their probability of developing behavior problems. The goal of this study is to examine how these analytes may interact to predict externalizing behavior in infants exposed to early stress. Participants included 179 parents and their 6- to 20-month old infants recruited from a low-income neighborhood. Parents reported on their infants' externalizing behaviors and collected saliva samples from their children at wake-up and bedtime over three days. Diurnal cortisol and alpha-amylase were modeled using latent difference scores. Four models were tested examining the effects of cortisol and alpha-amylase morning values and slopes, as well as their interactions, on externalizing behavior. Results showed a significant interaction effect of cortisol and alpha-amylase morning values, such that low morning cortisol was associated with decreased externalizing behavior when morning alpha-amylase was high but not low. These findings highlight the importance of examining multiple systems when characterizing the physiological correlates of externalizing behavior among infants experiencing adversity.

Childhood maltreatment interacts with hypothalamic-pituitary-adrenal axis negative feedback and major depression: effects on cognitive performance

ABSTRACT Background: Childhood maltreatment (CM) is associated with impaired hypothalamic-pituitary-adrenal (HPA) axis negative feedback and cognitive dysfunction, resembling those abnormalities linked to major depressive disorder (MDD). Objectives: We aimed to assess the potential modulating effects of MDD diagnosis or HPA axis function in the association between different types of CM and cognitive performance in adulthood. Methods: Sixty-eight MDD patients and 87 healthy controls were recruited. CM was assessed with the Childhood Trauma Questionnaire. We obtained three latent variables for neuropsychological performance (verbal memory, visual memory and executive function/processing speed) after running a confirmatory factor analysis with cognitive tests applied. Dexamethasone suppression test ratio (DSTR) was performed using dexamethasone 0.25 mg. Results: Different types of CM had different effects on cognition, modulated by MDD diagnosis and HPA axis function. Individuals with physical maltreatment and MDD presented with enhanced cognition in certain domains. The DSTR differentially modulated the association between visual memory and physical neglect or sexual abuse. Conclusions: HPA axis-related neurobiological mechanisms leading to cognitive impairment might differ depending upon the type of CM. Our results suggest a need for early assessment and intervention on cognition and resilience mechanisms in individuals exposed to CM to minimize its deleterious and lasting effects.

The status of serum cortisol before and after treatment of schizophrenia and its correlation to disease severity and improvement: A longitudinal study.

Background:Hypothalamic–pituitary–adrenal axis functioning, with cortisol as its major output hormone, has been presumed to play a key role in the development of psychopathology of schizophrenia.Objective:We examined the association of serum cortisol with disease severity and improvement in schizophrenia patients in Jimma, Ethiopia.Method:A total of 34 newly diagnosed schizophrenics were included in this study. Data on demographic, behavioral, clinical state, serum cholesterol level, and antipsychotic usage were obtained at baseline and after 8 weeks. The Positive and Negative Syndrome Scale was used to assess psychotic symptoms severity. A paired sample t-test was used to compare baseline and post-treatment values. Linear regression was used to assess associations.Result:Post-treatment serum cortisol level was significantly lower than its baseline value (p = 0.001). There was also a significant positive and negative psychotic symptoms decrease after treatment (baseline positive psychotic vs post-treatment positive psychotic symptoms: t(33) = 6.24 (95% confidence interval = 7.03,13.84, p = 0.000) and (baseline negative psychotic vs post-treatment negative psychotic symptoms: t(33) = 4.21 (95% confidence interval = 3.82, 10.99, p = 0.000).At baseline, neither positive nor negative subscore on the Positive and Negative Syndrome Scale showed an association with serum cortisol level (B = −0.016, p = 0.794 and B = −0.032, p = 0.594). However, serum cortisol level showed strong associations with post-treatment positive sub scores and negative sub scores (B = 0.167, p = 0.007) and (B = 0.144, p = 0.010) on the Positive and Negative Syndrome Scale.Conclusion:We found a significant decrease in serum cortisol level after antipsychotics treatment and that was associated with improvement in psychotic symptoms in schizophrenics in Jimma, Ethiopia.

Ex vivo glucocorticoid receptor-mediated IL-10 response predicts the course of depression severity

Directly measuring hypothalamic pituitary adrenal (HPA) axis function, an important player in affective disorders, is intensive and invasive. A crucial component of this system, the activity of the glucocorticoid receptor (GR), can be assessed ex vivo instead. Here, we investigated GR sensitivity in patients with major depressive disorder (MDD) to determine its predictive potential. Psychometric data and blood samples were collected from patients experiencing a major depressive episode (MDE, n = 87), healthy control subjects (n = 49), and patients with remitted MDD (n = 31) at baseline and (for patients) after median 20 days of follow-up after treatment as usual. Blood cells were stimulated ex vivo with lipopolysaccharide and the effect was suppressed by increasing dexamethasone (DEX) concentrations. The resultant cytokine secretion profile (for IL-6, IL-10, and TNF-α) was considered indicative of GR activity. Higher baseline scores of the Montgomery–Åsberg Depression Rating Scale (MADRS) were associated with a stronger decrease of logIC IL-6 (indicating an increase of GR sensitivity). Higher baseline logEC IL-10 (indicating a lower GR sensitivity) and a stronger reduction of logEC IL-10 (indicating a stronger increase in GR sensitivity) were associated with a stronger decrease in the MADRS score. Patients with remitted MDD showed higher logIC TNF-α values (indicating lower GR sensitivity) in comparison to patients with a current MDD at baseline and follow-up. Initially low GR sensitivity measured ex vivo in peripheral blood cells that increases over the course of treatment could serve as a predictive marker for stronger improvement in depression severity.