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Purpose: This study was conducted to assess the antidepressant effects of capsaicin in chronic depressive rats and elucidate the mechanism underlying its effects. Methods: Male Wistar rats (280~320 g, 8 weeks of age) were subjected to depression induced by chronic unpredictable mild stresses. The rats were exposed to 8 kinds of stresses for 8 weeks. In the last 2 weeks, fluoxetine or capsaicin was injected subcutaneously. The dose of fluoxetine was 10 mg/kg (body weight), while the doses of capsaicin consisted of low (1 mg/kg), middle (5 mg/kg), and high (10 mg/kg). The forced swim test (FST) was conducted to evaluate the immobility time of rats. The immobility time indicates despair, one of symptoms of depression. The change of tryptophan hydroxylase (TPH) in the dorsal raphe was investigated using immunohistochemistry. In the hippocampus cornu ammonis (CA) 1 and 3, glucocorticoid receptor (GR) expression was measured. Results: The immobility time in the FST was significantly lower (p < .05) in the low-dose (M = 32.40 ± 13.41 seconds) and middle-dose (M = 28.48 ± 19.57 seconds) groups than in the non-treated depressive rats (M = 90.19 ± 45.34 seconds). The amount of TPH in the dorsal raphe was significantly higher (p < .05) in the middle-dose (M = 249.17 ± 35.02) and high-dose (M = 251.0 ± 56.85) groups than in the non-treated depressive rats (M = 159.78 ± 41.16). However, GR expression in the hippocampus CA1 and CA3 did not show significant differences between the non-treated depressive rats and the capsaicin-injected rats. Conclusion: This study suggests that capsaicin produces an antidepressant-like effect on chronic unpredictable mild stress-induced depression in rats via the serotonin biosynthesis pathway. [ABSTRACT FROM AUTHOR]

Bovine alphaherpesvirus 1 (BoHV-1) is a persistent and recurring disease that affects cattle worldwide. It is a major contributor to bovine respiratory disease and reproductive failure in the US. A major complication of BoHV-1 arises from the lifelong latent infection established in the sensory ganglia of the peripheral nervous system following acute infection. Lifelong latency is marked by periodic reactivation from latency that leads to virus transmission and transient immunosuppression. Physiological and environmental stress, along with hormone fluctuations, can drive virus reactivation from latency, allowing the virus to spread rapidly. This review discusses the mechanisms of the latency/reactivation cycle, with particular emphasis on how different hormones directly regulate BoHV-1 gene expression and productive infection. Glucocorticoids, including the synthetic corticosteroid dexamethasone, are major effectors of the stress response. Stress directly regulates BoHV-1 gene expression through multiple pathways, including β-catenin dependent Wnt signaling, and the glucocorticoid receptor. Related type 1 nuclear hormone receptors, the androgen and progesterone receptors, also drive BoHV-1 gene expression and productive infection. These receptors form feed-forward transcription loops with the stress-induced Krüppel-like transcription factors KLF4 and KLF15. Understanding these molecular pathways is critical for developing novel therapeutics designed to block reactivation and reduce virus spread and disease. [ABSTRACT FROM AUTHOR]

Glucocorticoid stress hormones are produced in response to hypothalamic-pituitary-adrenal (HPA) axis activation. Glucocorticoids are essential for physiology and exert numerous actions via binding to the glucocorticoid receptor (GR). Relacorilant is a highly selective GR antagonist currently undergoing a phase 3 clinical evaluation for the treatment of endogenous Cushing's syndrome. It was found that increases in serum adrenocorticotropic hormone (ACTH) and cortisol concentrations after relacorilant treatment were substantially less than the increases typically observed with mifepristone, but it is unclear what underlies these differ ences. In this study, we set out to further preclinically characterize relacorilant in comparison to the classical but non-selective GR antagonist mifepristone. In human HEK-293 cells, relacorilant potently antagonized dexamethasone- and cortisol-induced GR signaling, and in human peripheral blood mononuclear cells, relacorilant largely prevented the anti-inflammatory effects of dexamethasone. In mice, relacorilant treatment preven ted hyperinsulinemia and immunosuppression caused by increased corticosterone exposure. Relacorilant treatment reduced the expression of classical GR target genes in peripheral tissues but not in the brain. In mice, relacorilant induced a modest disinhibition of the HPA axis as compared to mifepristone. In line with this, in mouse pituitary cells, relacorilant was generally less potent than mifepristone in regulating Pomc mRNA and ACTH release. This contrast between relacorilant and mifepristone is possibly due to the distinct transcriptional coregulator recruitment by the GR. In conclusion, relacorilant is thus an efficacious peripheral GR antagonist in mice with only modest dis inhibition of the HPA axis, and the distinct properties of relacorilant endorse the potential of selective GR antagonist treatment for endogenous Cushing's syndrome. [ABSTRACT FROM AUTHOR]

Steroid hormones are capable of diffusing through cell membranes to bind with intracellular receptors to regulate numerous physiological processes. Three classes of steroid hormones, namely androgens, estrogens and glucocorticoids, contribute to the development of the reproductive system and the maintenance of fertility. During the past 30 years, mouse models have been produced in which the expression of genes encoding steroid hormone receptors has been enhanced, partially compromised or eliminated. These mouse models have revealed many of the physiological processes regulated by androgens, estrogens and to a more limited extent glucocorticoids in the testis and male accessory organs. In this review, advances provided by mouse models that have facilitated a better understanding of the molecular regulation of testis and reproductive tract processes by steroid hormones are discussed. [ABSTRACT FROM AUTHOR]

In aquaculture, many stressors can negatively affect growth in teleosts. It is believed that cortisol performs glucocorticoid and mineralocorticoid functions because teleosts do not synthesize aldosterone. However, recent data suggest that 11-deoxycorticosterone (DOC) released during stress events may be relevant to modulate the compensatory response. To understand how DOC modifies the skeletal muscle molecular response, we carried out a transcriptomic analysis. Rainbow trout (Oncorhynchus mykiss) were intraperitoneally treated with physiological doses of DOC in individuals pretreated with mifepristone (glucocorticoid receptor antagonist) or eplerenone (mineralocorticoid receptor antagonist). RNA was extracted from the skeletal muscles, and cDNA libraries were constructed from vehicle, DOC, mifepristone, mifepristone plus DOC, eplerenone, and eplerenone plus DOC groups. The RNA-seq analysis revealed 131 differentially expressed transcripts (DETs) induced by DOC with respect to the vehicle group, mainly associated with muscle contraction, sarcomere organization, and cell adhesion. In addition, a DOC versus mifepristone plus DOC analysis revealed 122 DETs related to muscle contraction, sarcomere organization, and skeletal muscle cell differentiation. In a DOC versus eplerenone plus DOC analysis, 133 DETs were associated with autophagosome assembly, circadian regulation of gene expression, and regulation of transcription from RNA pol II promoter. These analyses indicate that DOC has a relevant function in the stress response of skeletal muscles, whose action is differentially modulated by GR and MR and is complementary to cortisol. [ABSTRACT FROM AUTHOR]

The glucocorticoid stress hormones affect brain function via high-affinity mineralocorticoid receptors (MRs) and lower-affinity glucocorticoid receptors (GRs). MR and GR not only differ in affinity for ligands, but also have distinct, sometimes opposite, actions on neuronal excitability and other cellular and higher-order parameters related to cerebral function. GR and MR messenger RNA (mRNA) levels are often used as a proxy for the responsiveness to glucocorticoids, assuming proportionality between mRNA and protein levels. This may be especially relevant for the MR, which because of its high affinity is already largely occupied at low basal (trough) hormone levels. Here we explore how GR and MR mRNA levels are associated with the expression of a shared target gene, glucocorticoid-induced leucine zipper (GILZ, coded by Tsc22d3) with basal and elevated levels of corticosterone in male mice, using in situ hybridization. Depending on the hippocampal subfield and the corticosterone levels, mRNA levels of MR rather than GR mostly correlated with GILZ mRNA in the hippocampus and hypothalamus at the bulk tissue level. At the individual cell level, these correlations were much weaker. Using publicly available single-cell RNA sequencing data, we again observed that MR and GR mRNA levels were only weakly correlated with target gene expression in glutamatergic and GABAergic neurons. We conclude that MR mRNA levels can be limiting for receptor action, but many other cell-specific and region-specific factors ultimately determine corticosteroid receptor action. Altogether, our results argue for caution while interpreting the consequences of changed receptor expression for the response to glucocorticoids. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that depression is often accompanied by an increase in mtDNA copy number and a decrease in ATP levels; however, the exact regulatory mechanisms remain unclear. Methods: In the present study, Western blot, cell knockdown, immunofluorescence, immunoprecipitation and ChIP-qPCR assays were used to detect changes in the Ahi1/GR-TFAM-mtDNA pathway in the brains of neuronal Abelson helper integration site-1 (Ahi1) KO mice and dexamethasone (Dex)-induced mice to elucidate the pathogenesis of depression. In addition, a rescue experiment was performed to determine the effects of regular exercise on the Ahi1/GR-TFAM-mtDNA-ATP pathway and depression-like behavior in Dex-induced mice and Ahi1 KO mice under stress. Results: In this study, we found that ATP levels decreased and mitochondrial DNA (mtDNA) copy numbers increased in depression-related brain regions in Dex-induced depressive mice and Ahi1 knockout (KO) mice. In addition, Ahi1 and glucocorticoid receptor (GR), two important proteins related to stress and depressive behaviors, were significantly decreased in the mitochondria under stress. Intriguingly, GR can bind to the D-loop control region of mitochondria and regulate mitochondrial replication and transcription. Importantly, regular exercise significantly increased mitochondrial Ahi1/GR levels and ATP levels and thus improved depression-like behaviors in Dex-induced depressive mice but not in Ahi1 KO mice under stress. Conclusions: In summary, our findings demonstrated that the mitochondrial Ahi1/GR complex and TFAM coordinately regulate mtDNA copy numbers and brain ATP levels by binding to the D-loop region of mtDNA Regular exercise increases the levels of the mitochondrial Ahi1/GR complex and improves depressive behaviors. BE2neeR3CuVf7a9CPyYjGY Video Abstract [ABSTRACT FROM AUTHOR]

Background and purpose: Continuous efforts have been made to move towards maintaining the beneficial anti‐inflammatory functions of glucocorticoids (GCs) while minimizing side effects. Here, we investigated the selective glucocorticoid receptor (GR) modulator‐like properties of a plant‐derived compound caesaldekarin e (CA‐e). Experimental approach: The therapeutic efficacy of CA‐e was evaluated in several mouse models, including dextran sulfate sodium‐induced colitis, ovalbumin‐induced lung allergic inflammation, imiquimod‐induced psoriasis‐like skin inflammation and skin atrophy. The action of CA‐e targeting the GR was analysed using molecular docking, cellular thermal shift assays and microscale thermophoresis. Other methods included DNA–protein pull‐down assays and mass spectrometry. Key results: CA‐e selectively inhibited positive GC response element ((+) GRE)‐mediated direct transactivation while maintaining and even enhancing the anti‐inflammatory effects of treatment with dexamethasone. CA‐e, alone and in combination with dexamethasone, efficiently alleviated inflammation in several mouse models with milder side effects compared with dexamethasone alone. Mechanistically, CA‐e inhibited the formation of dimers by binding to the dimerization interface located in the ligand‐binding domain of GR and facilitated embryonic ectoderm development that is involved in the regulation of transcriptional repression to compete for binding to (+) GRE, eventually leading to the repression of (+) GRE‐regulated genes. In addition, CA‐e repressed NF‐κB‐dependent genes by enhancing the interaction between GR and p65. Conclusions and implications: Our results reveal that CA‐e is a novel GR modulator with strong potency to attenuate the side effects of GC therapy and can be used as a potential molecular tool for deciphering GR signalling. [ABSTRACT FROM AUTHOR]

Objective: This work is to investigate the alterations of the central 5- hydroxytryptamine (5-HT) system in spontaneously hypertensive rats (SHR) and the correlation with the behaviors of SHR, and to explore the effects of glucocorticoid intervention on the central 5-HT system and SHR behaviors. Materials and methods: Three weeks old SHR were chosen as the attention-7deficit hyperactivity disorder (ADHD) model and treated with glucocorticoid receptor (GR) agonist or inhibitor, whereas Wista Kyoto rats (WKY) were chosen as the normal control group. Open-field test and Làt maze test were used to evaluate the spontaneous activities and non-selective attention. The levels of 5-HT in the extracellular fluid specimens of the prefrontal cortex of rats were analyzed by high-performance liquid chromatography. The expressions of GR, 5-HT1A receptor (5-HT1AR), and 5-HT2A receptor (5-HT2AR) in the prefrontal cortex were analyzed through immunohistochemistry. Results: Our study demonstrated that the 5-HT level was lower in the prefrontal cortex of SHR compared to that of WKY. The Open-field test and Làt maze test showed that GR agonist (dexamethasone, DEX) intervention ameliorated attention deficit and hyperactive behavior, whereas GR inhibitor (RU486) aggravated the disorders. With DEX, the expression levels of 5-HT and 5-HT2AR in the prefrontal cortex of SHR were significantly higher than those in the control group, whereas the expression level of 5-HT1AR was lower. However, the expression levels of 5-HT and 5-HT2AR were significantly decreased after the intervention with RU486, while the expression level of 5-HT1AR increased. Results showed that glucocorticoid was negatively correlated with 5-HT1AR and positively correlated with 5-HT2AR. Conclusion: In the prefrontal cortex of ADHD rats, the down-regulation of 5- HT and 5-HT2AR expressions and the up-regulation of 5-HT1AR, compared with WYK rats, suggested a dysfunctional central 5-HT system in ADHD rats. The GR agonist can upregulate the expression of 5-HT and 5-HT2AR and downregulate the expression of 5-HT1AR in the prefrontal cortex of SHR as well as reduce the hyperactivity and attention deficit behavior in SHR, while the opposite was true for the GR inhibitor. It is suggested that the dysfunction of the 5-HT system in ADHD rats is closely related to glucocorticoid receptor activity. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GCs) are anti-inflammatory and immunosuppressive steroid molecules secreted by the adrenal gland and regulated by the hypothalamic–pituitary–adrenal (HPA) axis. GCs present a circadian release pattern under normal conditions; they increase their release under stress conditions. Their mechanism of action can be via the receptor-independent or receptor-dependent pathway. The receptor-dependent pathway translocates to the nucleus, where the ligand-receptor complex binds to specific sequences in the DNA to modulate the transcription of specific genes. The glucocorticoid receptor (GR) and its endogenous ligand cortisol (CORT) in humans, and corticosterone in rodents or its exogenous ligand, dexamethasone (DEX), have been extensively studied in breast cancer. Its clinical utility in oncology has mainly focused on using DEX as an antiemetic to prevent chemotherapy-induced nausea and vomiting. In this review, we compile the results reported in the literature in recent years, highlighting current trends and unresolved controversies in this field. Specifically, in breast cancer, GR is considered a marker of poor prognosis, and a therapeutic target for the triple-negative breast cancer (TNBC) subtype, and efforts are being made to develop better GR antagonists with fewer side effects. It is necessary to know the type of breast cancer to differentiate the treatment for estrogen receptor (ER)-positive, ER-negative, and TNBC, to implement therapies that include the use of GCs. [ABSTRACT FROM AUTHOR]

Angelman Syndrome (AS) is a severe neurodevelopmental disorder, caused by the neuronal absence of the ubiquitin protein ligase E3A (UBE3A). UBE3A promotes ubiquitin-mediated protein degradation and functions as a transcriptional coregulator of nuclear hormone receptors, including the glucocorticoid receptor (GR). Previous studies showed anxiety-like behavior and hippocampal-dependent memory disturbances in AS mouse models. Hippocampal GR is an important regulator of the stress response and memory formation, and we therefore investigated whether the absence of UBE3A in AS mice disrupted GR signaling in the hippocampus. We first established a strong cortisol-dependent interaction between the GR ligand binding domain and a UBE3A nuclear receptor box in a high-throughput interaction screen. In vivo, we found that UBE3A-deficient AS mice displayed significantly more variation in circulating corticosterone levels throughout the day compared to wildtypes (WT), with low to undetectable levels of corticosterone at the trough of the circadian cycle. Additionally, we observed an enhanced transcriptomic response in the AS hippocampus following acute corticosterone treatment. Surprisingly, chronic corticosterone treatment showed less contrast between AS and WT mice in the hippocampus and liver transcriptomic responses. This suggests that UBE3A limits the acute stimulation of GR signaling, likely as a member of the GR transcriptional complex. Altogether, these data indicate that AS mice are more sensitive to acute glucocorticoid exposure in the brain compared to WT mice. This suggests that stress responsiveness is altered in AS which could lead to anxiety symptoms. [ABSTRACT FROM AUTHOR]

The availability of single nucleotide polymorphisms (SNPs) that have been identified in a given gene and have been related to several diseases provides the opportunity to study complex biological pathways and can assist researchers in better associating genes and disease-linked terms in the areas of genetics, genomics and epigenetics. The study of the glucocorticoid receptor (GR) interactome through SNP observations in 'key-player' genes will provide researcher with the opportunity to draw the 'genomic grammar' of the complex biological mechanisms associated with GR function and will open new horizons in biology, medicine, pharmacology and even extend to personalized medicine. The GR interactome is extensive, and is involved in several physiological and pathological processes of the organism. Glucocorticoids are the final product of the hypothalamic-pituitary-adrenal axis and an inextricable part of the stress system. These hormones are implicated in various critical systems and processes for the human organism, such as the immune system, development, metabolism and several others. GR is the protein that mediates their actions and is involved in several interactions with specific genes and proteins. In the present study, in order to unravel new beneficial knowledge on genetic targets regarding the GR interactome, a data mining and semantic pipeline was performed using the available literature. More specifically, through bioinformatics tools and methods, the most relevant SNPs and genes connected to the GR interactome were extracted. Subsequently, the outcome SNPs were filtered, annotated, classified and evaluated in order to create the 'genomic grammar' and identify the related disease with the interactome of GR. Genomic background and heredity play a significant role in the GR interactome. A more in-depth understanding of the biological pathways and complex actions of the GR may lead to the design and development of more effective treatments for inflammatory and autoimmune diseases, as well as cancers. [ABSTRACT FROM AUTHOR]

Prenatal stress (PS) causes anxiety in mothers and their offspring and chewing is a commonly observed behavior during maternal stress. Prolactin (PRL) is an anti‐anxiety factor that suppresses the hypothalamic–pituitary–adrenal axis. Here, we studied the roles of PRL, corticosterone (CORT), and their receptors in PS‐induced anxiety‐like behavior in dams and their offspring. We further investigated whether chewing during maternal stress could prevent PS‐induced harmful consequences. Pregnant rats were randomly divided into PS, PS + chewing, and control groups. Anxiety‐like behaviors of dams and their adolescent offspring were assessed using the open field test and elevated plus maze. Serum levels of PRL and CORT were measured by ELISA. Expression of mRNA and protein of PRLR and glucocorticoid receptor (GR) in the prefrontal cortex (PFC) were evaluated by qRT‐PCR and western blotting, respectively. Compared to the control rats, dams and their female offspring, but not male offspring, in the PS group showed increased anxiety‐like behaviors. The PS‐affected rats had a lower serum PRL level and increased PRLR expression in the PFC. In contrast, these rats had a higher serum CORT level and decreased GR expression in the PFC. Chewing ameliorated anxiety‐like behaviors and counteracted stress‐induced changes in serum PRL and CORT, as well as the expression of their receptors in the PFC. Conclusion: PS‐induced anxiety‐like behavior is associated with changes in the serum levels of PRL and CORT and expression of their receptors in the PFC. Moreover, chewing blunts the hormonal and receptor changes and may serve as an effective stress‐coping method for preventing PS‐induced anxiety‐like behavior. [ABSTRACT FROM AUTHOR]

Social anhedonia is a psychological state with difficulty in experiencing pleasure from social interactions and is observed in various diseases, such as depressive disorders. Although the relationships between social reward responses and anxiety- and depression-like behaviors have remained unclear, a social reward conditioned place preference (SCPP) test can be used to analyze the rewarding nature of social interactions. To elucidate these relationships, we used 5-week-old male mice of AKR, BALB/c, and C57BL/6J strains and conducted behavioral tests in the following order: elevated plus-maze test (EPM), open field test (OFT), SCPP, saccharin preference test (SPT), and passive avoidance test. The nucleus accumbens of these mice were collected 24 hr after these behavioral tests and were used for western blotting to determine the levels of receptors for brainderived neurotrophic factors and glucocorticoids. BALB/c mice displayed the highest levels of anxiety-like behavior in EPM and OFT as well as physical anhedonia-like behaviors in SPT. They also showed increased responses to social rewards and huddling behaviors in SCPP, with downregulated glucocorticoid receptor (GR). Regression analysis results revealed positive influences of anxiety- and physical anhedonia-like behaviors and expressions of GR on social reward responses. Collectively, temperament associated with anxiety and physical anhedonia may affect social reward responses, which possibly is influenced by the expression of GR that can modify these psychological traits. [ABSTRACT FROM AUTHOR]

Maternal prenatal psychosocial stress is associated with adverse hypothalamic–pituitary–adrenal axis (HPAA) function among infants. Although the biological mechanisms influencing this process remain unknown, altered DNA methylation is considered to be one potential mechanism. We investigated associations between maternal prenatal psychological distress, infant salivary DNA methylation, and stress physiology at 12 months. Mother's distress was measured via depression and anxiety in early and late pregnancy in a cohort of 80 pregnant adolescents. Maternal hair cortisol was collected during pregnancy. Saliva samples were collected from infants at 12 months to quantify DNA methylation of three stress‐related genes (FKBP5, NR3C1, OXTR) (n = 62) and diurnal cortisol (n = 29). Multivariable linear regression was used to test for associations between prenatal psychological distress, and infant DNA methylation and cortisol. Hair cortisol concentrations in late pregnancy were negatively associated with two sites of FKBP5 (site 1: B = −22.33, p =.003; site 2: B = −15.60, p =.012). Infants of mothers with elevated anxiety symptoms in late pregnancy had lower levels of OXTR2 CpG2 methylation (B = −2.17, p =.03) and higher evening salivary cortisol (B = 0.41, p =.03). Furthermore, OXTR2 methylation was inversely associated with evening cortisol (B = −0.14, p‐value ≤.001). Our results are, to our knowledge, the first evidence that the methylation of the oxytocin receptor may contribute to the regulation of HPAA during infancy. [ABSTRACT FROM AUTHOR]

Jujuboside B (JB) found in the seeds of Zizyphi Spinosi Semen possesses pharmacological functions, such as anti-inflammatory, antiplatelet aggregation, and antianxiety potentials. This study evaluated the effect of JB on liver failure in cecal ligation and puncture (CLP)-induced sepsis. First, we observed histopathological changes in the liver by optical microscopy and the activity of enzymes in serum such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We further measured the levels of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, nitric oxide (NO), and antioxidative parameters in liver homogenate. The expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), and glucocorticoid receptor (GR) in the liver was observed by Western blotting. CLP enhanced the migration of inflammatory cells, ALT and AST concentrations, and necrosis, which were reduced by JB. In addition, JB reduced 11β-HSD2 expression and levels of inflammatory mediators (TNF-α, IL-1β, and NO) in the liver, increased GR expression, enhanced endogenous antioxidative capacity. These results further suggest that JB may protect the liver against CLP-induced damage by regulating anti-inflammatory responses, downregulating 11β-HSD2 expression and antioxidation, and up-regulating GR expression. [ABSTRACT FROM AUTHOR]

Steroid-induced osteonecrosis of femoral head (SONFH) is one of the most common bone disorders in humans. Statin treatment is beneficial in preventing the development of SONFH through anti-inflammation effects and inhibition of the glucocorticoid receptor (GR). However, potential mechanisms of statin action remain to be determined. In this study, pulse methylprednisolone (MP) treatment was used to induce SONFH in broilers, and then MP-treated birds were administrated with simvastatin simultaneously to investigate the changes in cartilage homeostasis. Meanwhile, chondrocytes were isolated, cultured, and treated with MP, simvastatin, or GR inhibitor in vitro. The changes in serum homeostasis factors, cell viability, and expression of GR were analyzed. The results showed that the morbidity of SONFH in the MP-treated group increased significantly compared with the simvastatin-treated and control group. Furthermore, MP treatment induced apoptosis and high-level catabolism and low-level anabolism in vitro and vivo, while simvastatin significantly decreased catabolism and slightly recovered anabolism via inhibiting GR and the hypoxia-inducible factor (HIF) pathway. The GR inhibitor or its siRNA mainly affected the catabolism of cartilage homeostasis in vitro. In conclusion, the occurrence of SONFH in broilers was related to the activation of GR and HIF pathway, and imbalance of cartilage homeostasis. Simvastatin and GR inhibitor maintained cartilage homeostasis via GR and the HIF pathway. [ABSTRACT FROM AUTHOR]

Alcoholic hepatitis is a major health and economic burden worldwide. Glucocorticoids (GCs) are the only first-line drugs recommended to treat severe alcoholic hepatitis (sAH), with limited short-term efficacy and significant side effects. In this review, I summarize the major benefits and side effects of GC therapy in sAH and the potential underlying mechanisms. The review of the literature and data mining clearly indicate that the hepatic signaling of glucocorticoid receptor (GR) is markedly impaired in sAH patients. The impaired GR signaling causes hepatic down-regulation of genes essential for gluconeogenesis, lipid catabolism, cytoprotection, and anti-inflammation in sAH patients. The efficacy of GCs in sAH may be compromised by GC resistance and/or GC's extrahepatic side effects, particularly the side effects of intestinal epithelial GR on gut permeability and inflammation in AH. Prednisolone, a major GC used for sAH, activates both the GR and mineralocorticoid receptor (MR). When GC non-responsiveness occurs in sAH patients, the activation of MR by prednisolone might increase the risk of alcohol abuse, liver fibrosis, and acute kidney injury. To improve the GC therapy of sAH, the effort should be focused on developing the biomarker(s) for GC responsiveness, liver-targeting GR agonists, and strategies to overcome GC non-responsiveness and prevent alcohol relapse in sAH patients. [ABSTRACT FROM AUTHOR]

The hypothalamus–pituitary–adrenal axis is the main physiological stress response system and regulating the release of cortisol. The two corticoid receptors encoded by the genes NR3C1 and NR3C2 are the main players in regulating the physiological response to cortisol. This biological system has been linked to neurocognitive processes and memory, yet the mechanisms remain largely unclear. In two independent general population studies (SHIP, total sample size > 5500), we aim to diseantangle the effects of genetic variation, gene expression and cortisol on verbal memory and memory associated brain volume. Especially for NR3C1 results exhibited a consistent pattern of direct an interactive effects. All three biological layers, genetic variation (rs56149945), gene expression for NR3C1 and cortisol levels, were directly associated with verbal memory. Interactions between these components showed significant effects on verbal memory as well as hippocampal volume. For NR3C2 such a complex association pattern could not be observed. Our analyses revealed that different components of the stress response system are acting together on different aspects of cognition. Complex phenotypes, such as cognition and memory function are regulated by a complex interplay between different genetic and epigenetic features. We promote the glucocorticoid receptor NR3C1 as a main target to focus in the context of verbal memory and provided a mechanistic concept of the interaction between various biological layers spanning NR3C1 function and its effects on memory. Especially the NR3C1 transcript seemed to be a key element in this complex system. [ABSTRACT FROM AUTHOR]

Glucocorticoids are steroids involved in key physiological processes such as development, metabolism, inflammatory and stress responses and are mostly used exogenously as medications to treat various inflammation-based conditions. They act via the glucocorticoid receptor (GR) expressed in most cells. Exogenous glucocorticoids can negatively impact the function of the Leydig cells in the testis, leading to decreased androgen production. However, endogenous glucocorticoids are produced by the adrenal and within the testis, but whether their action on GR in Leydig cells regulates steroidogenesis is unknown. This study aimed to define the role of endogenous GR signalling in adult Leydig cells. We developed and compared two models; an inducible Cre transgene driven by expression of the Cyp17a1 steroidogenic gene (Cyp17-iCre) that depletes GR during development and a viral vector-driven Cre (AAV9-Cre) to deplete GR in adulthood. The delivery of AAV9-Cre ablated GR in adult mouse Leydig cells depleted Leydig cell GR more efficiently than the Cyp17-iCre model. Importantly, adult depletion of GR in Leydig cells caused reduced expression of luteinising hormone receptor (Lhcgr) and of steroidogenic enzymes required for normal androgen production. These findings reveal that Leydig cell GR signalling plays a physiological role in the testis and highlight that a normal balance of glucocorticoid activity in the testis is important for steroidogenesis. [ABSTRACT FROM AUTHOR]

The conjugation of drugs with nanoparticles represents an innovative approach for controlled and targeted administration of therapeutic agents. Nanoparticle-based systems have been tested for the inner ear therapy, increasing the drug diffusion and being detected in all parts of the cochlea when locally applied near the round window. In this study, glycerol monooleate liquid crystalline NanoParticles were conjugated with Dexamethasone (NPD), a hydrophobic drug already used for inner ear treatments but defective in solubility and bioavailability. NPD has been tested in vitro in the cell line OC-k3, a model of sensory cells of the inner ear, and the therapeutic efficacy has been evaluated against cisplatin, a chemotherapeutic compound known to induce ototoxicity. After comparing the physical chemical characteristics of NPD to the equivalent naïve nanoparticles, an initial investigation was carried out into the nanoparticle's uptake in OC-k3 cells, which takes place within a few hours of treatment without causing toxic damage up to a concentration of 50 µg/mL. The NPD delivered the dexamethasone inside the cells at a significantly increased rate compared to the equivalent free drug administration, increasing the half-life of the therapeutic compound within the cell. Concerning the co-treatment with cisplatin, the NPD significantly lowered the cisplatin cytotoxicity after 48 h of administration, preventing cell apoptosis. To confirm this result, also cell morphology, cell cycle and glucocorticoids receptor expression were investigated. In conclusion, the NPD system has thus preliminarily shown the potential to improve the therapeutic efficacy of treatments delivered in the inner ear and prevent drug-induced ototoxicity. [ABSTRACT FROM AUTHOR]

Problem: Both luteal phase progesterone (P4) levels and use of the intramuscular (IM) injectable progestin‐only contraceptive depo‐medroxyprogesterone acetate (DMPA‐IM) have been linked to increased S/HIV acquisition in animal, clinical and in vitro models. Several plausible mechanisms could explain MPA‐induced HIV‐1 acquisition while those for the luteal phase are underexplored. Method of study: Peripheral blood mononuclear cells (PBMCs) were treated with P4 and estrogen at concentrations mimicking the luteal phase, follicular phase or with levels of MPA mimicking peak serum levels in DMPA‐IM users. Cells were infected with an R5‐tropic infectious molecular clone and HIV‐1 infection was measured. A role for the glucocorticoid receptor (GR) was investigated using the GR/PR antagonist RU486. CCR5 protein levels and activation status, assessed by levels of the activation marker CD69, were measured by flow cytometry after treatment in vitro and in PBMCs from naturally‐cycling women or DMPA‐IM users. Results: Both MPA and luteal phase hormones significantly increased HIV‐1 infection in vitro. However, MPA but not luteal phase hormones increased the CD4+/CD8+ T cell ratio, CCR5 protein expression on CD4+ T cells and increased expression of the activation marker CD69. The GR is involved in MPA‐induced, but not luteal phase hormone‐induced increased HIV‐1 infection. In DMPA‐IM users, the frequency of CCR5‐expressing CD3+ and CD8+ cells was higher than for women in the luteal phase. Conclusions: MPA increases HIV‐1 infection in a manner different from that of luteal phase hormones, most likely involving the GR and at least in part changes in the frequency and/or expression of CCR5 and CD69. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GCs), mostly dexamethasone (dex), are routinely administered as adjuvant therapy to manage side effects in breast cancer. However, recently, it has been revealed that dex triggers different effects and correlates with opposite outcomes depending on the breast cancer molecular subtype. This has raised new concerns regarding the generalized use of GC and suggested that the context-dependent effects of GCs can be taken into potential consideration during treatment design. Based on this, attention has recently been drawn to the role of the glucocorticoid receptor (GR) in development and progression of breast cancer. Therefore, in this comprehensive review, we aimed to summarize the different mechanisms behind different context-dependent GC actions in breast cancer by applying a multilevel examination, starting from the association of variants of the GR-encoding gene to expression at the mRNA and protein level of the receptor, and its interactions with other factors influencing GC action in breast cancer. The role of GCs in chemosensitivity and chemoresistance observed during breast cancer therapy is discussed. In addition, experiences using GC targeting therapeutic options (already used and investigated in preclinical and clinical trials), such as classic GC dexamethasone, selective glucocorticoid receptor agonists and modulators, the GC antagonist mifepristone, and GR coregulators, are also summarized. Evidence presented can aid a better understanding of the biology of context-dependent GC action that can lead to further advances in the personalized therapy of breast cancer by the evaluation of GR along with the conventional estrogen receptor (ER) and progesterone receptor (PR) in the routine diagnostic procedure. [ABSTRACT FROM AUTHOR]

The extraction of bitumen from surface mining in the Athabasca Oil Sands Region (AOSR) produces large quantities of oil sands process‐affected water (OSPW) that needs to be stored in settling basins near extraction sites. Chemical constituents of OSPW are known to impair bone health in some organisms, which can lead to increased fracture risk and lower reproductive fitness. Naphthenic acid fraction components (NAFCs) are thought to be among the most toxic class of compounds in OSPW; however, the effect of NAFCs on osteoblast development is largely unknown. In this study, we demonstrate that NAFCs from OSPW inhibit osteoblast differentiation and deposition of extracellular matrix, which is required for bone formation. Extracellular matrix deposition was inhibited in osteoblasts exposed to 12.5–125 mg/L of NAFC for 21 days. We also show that components within NAFCs inhibit the expression of gene markers of osteoblast differentiation and function, namely, alkaline phosphatase (Alp), osteocalcin, and collagen type 1 alpha 1 (Col1a1). These effects were partially mediated by the induction of glucocorticoid receptor (GR) activity; NAFC induces the expression of the GR activity marker genes Sgk1 (12.5 mg/L) and p85a (125 mg/L) and inhibits GR protein (125 mg/L) and Opg RNA (12.5 mg/L) expression. This study provides evidence that NAFC concentrations of 12.5 mg/L and above can directly act on osteoblasts to inhibit bone formation and suggests that NAFCs contain components that can act as GR agonists, which may have further endocrine disrupting effects on exposed wildlife. Surface mining in the Athabasca Oil Sands Region (AOSR) produces large quantities of oil sands process‐affected water (OSPW), constituents of which are known to impair bone health in some organisms. Naphthenic acid fraction components (NAFCs) are thought to be responsible for most of the toxic effect of OSPW, but their effects on bone are unknown. In this study, we demonstrate that NAFCs extracted from the AOSR inhibit osteoblast differentiation and may act via the glucocorticoid receptor. [ABSTRACT FROM AUTHOR]

Abstract Background Recent studies suggest that the incidence of infant sleep disorder is related to maternal emotional and sleep conditions, but how they influence each other is not fully understood. Methods A total of 513 pairs of parents and infants were enrolled in this prospective cohort study. Maternal emotional and sleep conditions were assessed using a self-rating depression scale, self-rating anxiety scale, and Pittsburgh Sleep Quality Index at the third trimester and within 3 months after delivery. Infant sleep was assessed by the Brief Screening Questionnaire for Infant Sleep Problems within 3 months after birth. Expression of the glucocorticoid receptor (GR), melatonin receptors (MR), exchange proteins directly activated by cAMP (EPAC) receptors, and dopamine receptor (DR) in the placenta was detected by immunohistochemistry. Methylation of the promoter regions for the GR (NR3C1 and NR3C2), MR (MTNR1A and MTNR1B), EPAC (RASGRF1 and RASGRF2), and DR (DRD1 and DRD2) genes was assessed by next generation sequencing-based bisulfite sequencing PCR. Results The incidence of sleep disorders in infants 0–3 months of age in this cohort was 40.5%. Risk factors for infant sleep disorder were low education level of the father, depression of father, maternal postpartum depression, postpartum anxiety, postpartum sleep disorder, and maternal sleep disorder extend from the third trimester to postpartum. There was no difference in expression of placental DR, GR, MR, and EPAC between mothers whose infants were with and without sleep disorders. Methylation of MTNR1B was higher and expression of MR was lower in the placenta of mothers with sleep disorder in the third trimester than in mothers without sleep disorder. Level of NR3C2 methylation was lower and GR expression was higher in the placenta of mothers with sleep disorder extend from the third trimester to postpartum than in mothers without sleep disorder. Conclusion Maternal sleep disorders in the third trimester could lead to decreased MR expression by up-regulating MTNR1B methylation, and then resulting in elevated cortisol and increased GR expression by down-regulating NR3C2 methylation, which could increase the incidence of maternal postpartum sleep disorders, finally, the maternal postpartum sleep disorder could result in the high incidence of infant sleep disorder.

Test anxiety may be a contributing factor to low-performing examination scores among students. There can be numerous physiological responses in the body that lead to test anxiety. One is the body’s response to stress, which activates the brain to release hormones that stimulate central and peripheral nervous responses. The hypothalamus–pituitary–adrenal (HPA) axis is a known responder during stress, causing an elevation of cortisol in the blood, a glucocorticoid (GC) hormone that affects sympathetic nervous responses. Stressors during testing include the method of information delivered, prior knowledge of the subject material, emotional state, or how accurately the student can retain knowledge. A student’s emotional state of mind is essential and may cause hyperactivation of the HPA axis during stress encountered during testing, exacerbating cortisol levels and nervous responsiveness. This review discusses the potential involvement of the HPA stress axis on an individual’s performance during testing and assessment.

Introduction. Glucocorticoids are often used in combination therapy for breast cancer as an adjuvant to increase therapeutic effects of the main cytotoxic drug and to reduce side effects of chemotherapy. However, glucocorticoids can cause serious complications and trigger tumor progression. In the last decade, it was found that side effects from glucocorticoids are mediated by an increase in REDD1 gene expression. Using this knowledge, we have developed a new chemotherapeutic strategy for blood cancers aimed at reducing adverse events from glucocorticoids. Successful experiments with a combination of glucocorticoids and REDD1 expression inhibitors on the models of blood tumors allowed us to use this regimen for the treatment of certain subtypes of breast cancer.Objective: to optimize the algorithm of breast cancer cell treatment with a combination of glucocorticoids and REDD1 expression inhibitors on the example of rapamycin.Materials and methods. We used the MCF-7 and MDA-MB-231 breast cancer cell lines. The antiproliferative activity was estimated by direct cell count; REDD1 expression was measured using western blotting and quantitative polymerase chain reaction.Results. We found that rapamycin can inhibit both baseline and glucocorticoids induced REDD1 expression in the cells of luminal and triple negative breast cancer. The drug demonstrated lower ability to inhibit the viability of breast cancer cells than that of leukemia and lymphoma cells.Conclusion. Inhibited proliferation of breast cancer cells after their incubation with rapamycin and dexamethasone, as well as the ability of rapamycin to reduce basal and glucocorticoid-induced REDD1 expression in breast cancer cells suggest the importance of studies analyzing the impact of combinations that include glucocorticoids and REDD1 expression inhibitors from the class of PI3K/Akt/mTOR signaling pathway modulators (phosphoinositide-3-kinase/α-serine-threonine kinase/mammalian rapamycin target) on breast cancer cells.

Constant efforts have been made to move towards maintaining the positive anti-inflammatory functions of glucocorticoids (GCs) while minimizing side effects. The anti-inflammatory effect of GCs is mainly attributed to the inhibition of major inflammatory pathways such as NF-κB through GR transrepression, while its side effects are mainly mediated by transactivation. Here, we investigated the selective glucocorticoid receptor modulator (SGRM)-like properties of a plant-derived compound. In this study, glucocorticoid receptor (GR)-mediated alleviation of inflammation by SP-8 was investigated by a combination of in vitro, in silico, and in vivo approaches. Molecular docking and cellular thermal shift assay suggested that SP-8 bound stably to the active site of GR via hydrogen bonding and hydrophobic interactions. SP-8 activated GR, induced GR nuclear translocation, and inhibited NF-κB pathway activation. Furthermore, SP-8 did not up-regulate the gene and protein expression of PEPCK and TAT in HepG2 cells, and it did not induce fat deposition like GC and has little effect on bone metabolism. Interestingly, SP-8 upregulated GR protein expression and did not cause GR phosphorylation at Ser211 in RAW264.7 cells. This work proved that SP-8 dissociated characteristics of transrepression and transactivation can be separated. In addition, the in vitro and in vivo anti-inflammatory effects of SP-8 were confirmed in LPS-induced RAW 264.7 cells and in a mouse model of DSS-induced ulcerative colitis, respectively. In conclusion, SP-8 might serve as a potential SGRM and might hold great potential for therapeutic use in inflammatory diseases. [Display omitted] • SP-8 binds to and translocates glucocorticoid receptor (GR) into the nucleus. • SP-8 reduces the secretion of pro-inflammatory cytokines in vitro and in vivo. • SP-8 cannot induce the transactivation of GR. • Computer simulations confirm the binding stability of SP-8 with GR. • SP-8 may be a potential selective GR modulator (SGRM). [ABSTRACT FROM AUTHOR]

Euonymus alatus (Thunb.) Siebold. (EA), a traditional Chinese medicine, is widely used in the treatment of diabetes. Our group has previously found that EA could treat diabetic retinopathy (DR) and stigmast-4-en-3-one (Numbered E6) is the active substance responsible for inhibiting angiogenesis in vitro by EA. However, the effects and mechanisms of E6 in the treatment of DR is still unknown. The aim of this study was to investigate the effects and mechanisms of E6 in EA on DR. Additionally, a comparison was made between the effects of E6 and triamcinolone acetonide (TA), as well as the side effects of E6 and dexamethasone. Ocular affinity assessment and pharmacokinetic parameter prediction were conducted to evaluate the potential of E6 to treat DR. Retinal endothelial cells were used to investigate the in vitro inhibitory effect of E6 on vascular proliferation. Additionally, chicken embryos, zebrafish, and mice were used to investigate the in vivo anti-vascular proliferation effect of E6. Finally, diabetic mice were used to investigate whether E6 improves diabetic retinopathy and to compare its efficacy with that of TA. We then used network pharmacology to study the targets of E6 and performed molecular docking; followed by immunofluorescence experiments, ELISA, Western blot, and tube formation experiments to further investigate its mechanism. Finally, we compared the side effects of E6 with those of dexamethasone. E6 was found to have an affinity for the eye and to inhibit vascular proliferation both in vivo and in vitro. Moreover, E6 was found to be more efficacious than TA in the treatment of DR. Molecular docking experiments predicted that the glucocorticoid receptor (GR) is a potential target of E6, and immunofluorescence analyses confirmed that E6 upregulated the expression of the GR in the retina of hyperglycemic mice. In addition, western blotting results and tube formation experiments showed that E6 also attenuated angiogenesis by inhibiting the Hippo and VEGF pathways. Finally, by comparing the effects of E6 and dexamethasone on glucose regulation and osteoporosis, E6 was found to have fewer side effects. E6 is a highly effective drug for the treatment of DR, superior to TA and with fewer side effects than dexamethasone. Its mechanism involves the activation of glucocorticoid receptor and inhibition of Hippo and VEGF pathways to alleviate angiogenesis and inflammation. This study is the first to investigate the role and mechanism of E6 in improving DR. The findings suggest that E6 has unique advantages in the treatment of DR. [Display omitted] • This is the first study of E6 in DR treatment. • E6 is a highly effective drug for the treatment of DR. • E6 is superior to triamcinolone acetonide. • E6 has fewer side effects than dexamethasone. [ABSTRACT FROM AUTHOR]

Multiple factors contribute to the development of perioperative neurocognitive disorders (PND). This study was designed to investigate whether Histone Deacetylase 6 (HDAC6) was involved in the formation of postoperative cognitive dysfunction in elderly mice by regulating the degree of acetylation of heat shock protein (HSP90) and related protein functions and quantities. C57BL/6 J male mice were randomly divided into six groups: control naive (group Control), anesthesia (group Anesthesia), splenectomy surgery (group Surgery), splenectomy surgery plus dissolvent (group Vehicles), splenectomy surgery plus the inhibitor ACY-1215 (group Ricolinostat), and splenectomy surgery plus the inhibitor RU-486(group Mifepristone). After the mice were trained for Morris Water Maze (MWM) test for five days, anesthesia and operational surgery were carried out the following day. Cognitive function was assessed on the 1st, 3rd and 7th days post-surgery. The hippocampi were harvested on days 1, 3, and 7 post-surgeries for Western blots and ELISA assays. Mice with the splenectomy surgery displayed the activation of the hypothalamic–pituitary–adrenal axis (HPA-axis), marked an increase in adrenocorticotropic hormone (ACTH), glucocorticoid, mineralocorticoid at the molecular level and impaired spatial memory in the MWM test. The hippocampus of surgical groups showed a decrease in acetylated HSP90, a rise in glucocorticoid receptor (GR)-HSP90 association, and an increase in GR phosphorylation and translocation. HDAC6 was increased after the surgical treated. Using two specific inhibitors, HDAC6 inhibitor Ricolinostat (ACY-1215) and GR inhibitor Mifepristone (RU-486), can partially mitigate the effects caused by surgical operation. Abdominal surgery may impair hippocampal spatial memory, possibly through the HDAC6-triggered increase in the function of HSP90, consequently strengthening the negative role of steroids in cognitive function. Targeting HDAC6- HSP90/GR signaling may provide a potential avenue for the treatment of the impairment of cognitive function after surgery. • Revealed Peripheral changes such as HPA-Axis activation are related to PND in aged mice. • Surgery induced HDAC6 increased are involved in PND of aged mice. • The HDAC6 downstream protein HSP90 plays a role in the development of PND. • Injected the HDAC6 inhibitor and GR inhibitor can partly reversal the behavior of cognitive impairment. [ABSTRACT FROM AUTHOR]

Breast cancer incidence has been steadily rising and is the leading cause of cancer death in women due to its high metastatic potential. Individual breast cancer subtypes are classified by both cell type of origin and receptor expression, namely estrogen, progesterone and human epidermal growth factor receptors (ER, PR and HER2). Recently, the importance and context-dependent role of glucocorticoid receptor (GR) expression in the natural history and prognosis of breast cancer subtypes have been uncovered. In ER-positive breast cancer, GR expression is associated with a better prognosis as a result of ER-GR crosstalk. GR appears to modulate ER-mediated gene expression resulting in decreased tumor cell proliferation and a more indolent cancer phenotype. In ER-negative breast cancer, including GR-positive triple-negative breast cancer (TNBC), GR expression enhances migration, chemotherapy resistance and cell survival. In invasive lobular carcinoma, GR function is relatively understudied, and more work is required to determine whether lobular subtypes behave similarly to their invasive ductal carcinoma counterparts. Importantly, understanding GR signaling in individual breast cancer subtypes has potential clinical implications because of the recent development of highly selective GR non-steroidal ligands, which represent a therapeutic approach for modulating GR activity systemically. • Glucocorticoid receptor (GR) is expressed in about 60% of both estrogen receptor positive (ER+) and negative (ER-) breast cancers. • Glucocorticoid receptor transcriptional activity is breast cancer subtype dependent (e.g. luminal versus basal). • GR activation inhibits proliferation in ER+ breast cancer cells. • GR-mediated gene expression pathways (e.g. EMT, cell survival, metastasis) are associated with worse TNBC prognosis. [ABSTRACT FROM AUTHOR]

As a compound derived from cruciferous vegetables, sulforaphane showed promise in depression treatment. This study aimed to investigate its effects on the hypothalamic-pituitary-adrenal (HPA) axis and glucocorticoid receptor (GR) function using a chronic corticosterone (CORT)-induced cell and mouse model. We evaluated the effects of sulforaphane on depression-like behavior, pathology, hormone levels, inflammation, GR expression, and hippocampal proteins. Additionally, molecular docking was conducted to explore sulforaphane's binding interaction with GR. Results showed that CORT exposure reduced GR expression, increased stress hormones and pro-inflammatory cytokines, decreased BDNF-related pathway activity, and intensified GR nuclear translocation. Sulforaphane administration reversed these effects, improving depression-like behavior. Molecular docking showed sulforaphane fitting into the GR pocket, forming hydrogen bonds and hydrophobic interactions, with a binding free energy of −4.92 kcal/mol. These findings suggest that sulforaphane exerted neuroprotective and antidepressant effects by modulating GR expression and mitigating inflammation-induced apoptosis and impaired neuroplasticity, likely mediated through the NF-κB and ERK/CREB/BDNF pathways. [ABSTRACT FROM AUTHOR]

Neonates undergo numerous painful procedures throughout their hospitalization. Repeated procedural pain may cause adverse long-term effects. Glucose as a non-pharmacological analgesia, is used for neonate pain management. In this study, potential mechanism of attenuate pain induced by glucose in neurodevelopment effect of neonate pain stimulus was investigated. Neonatal rats to perform a repetitive injury model and glucose intervention model in the postnatal day 0–7(P0-7). Pain thresholds were measured by von Frey test weekly. The puberty behavioral outcome, tissue loss and protein expression in hippocampus were analyzed. Oral administration of glucose after repeated pain stimulation can maintain the hippocampal structure in, and reduce the expressions of corticotropin releasing factor (CFR) and glucocorticoid receptor (GR), therefore, resulted in long-term threshold of pain and cognitive improvement. Exposure to neonatal repeated procedural pain causes persistent mechanical hypersensitivity and the dysfunction of spatial memory retention at puberty. In addition, glucose can relieve these adverse effects, possibly via decreasing CRF/GR levels to change the hypothalamus-pituitary-adrenal (HPA) axis. • Repetitive neonatal procedural pain results in hyperesthesia and impaired cognition ability and memory retention at puberty. • CRF/GR protein expressed higher in the hippocampus after repeated procedural pain stimulation. • Glucose attenuates the adverse effects of pain by inhibiting the CRF/GR protein expression. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GCs) have a wide spectrum of effects on animal behavior. A recently suggested effect involves determining the structure of individual differences, that is how the behavioral traits of an individual covary, forming the so-called behavioral syndromes. As GCs can exert their action in multiple ways, e.g., via rapid non-genomic effects or via the activation of two highly homologous members of the steroid receptor family acting as transcription factors, it is unclear how the GC modulation of behavioral syndromes takes place. We exploited a zebrafish line with a frameshift mutation in the gene encoding the GC receptor (Gr), to investigate this question. We found that lack of Gr altered the average score of several behavioral traits in the mutant line, determining reduced boldness, and increased activity and sociability. Critically, the pattern of covariation between these traits was also substantially affected by the loss of Gr. The most evident effect was an association of traits involved in boldness in the gr mutant line. This study reveals that, in zebrafish, Gr is not only involved in the modulation of the average value of behavioral traits, but also in how the behavioral traits of an individual are interrelated and determine the behavioral syndromes. • GR loss determined average differences in boldness, activity and sociability. • Individual level correlations between behavioral traits were affected by GR loss. • Boldness traits were part of the syndrome only in absence of GR. • GR modulates relations between behavioral traits and thus behavioral syndromes. [ABSTRACT FROM AUTHOR]

In humans, glucocorticoid resistance is attributed to mutations in the glucocorticoid receptor (GR). Most of these mutations result in decreased ligand binding, transactivation, and/or translocation, albeit with normal protein abundances. However, there is no clear genotype‒phenotype relationship between the severity or age at disease presentation and the degree of functional loss of the receptor. Previously, we documented that a GR+/− rat line developed clinical features of glucocorticoid resistance, namely, hypercortisolemia, adrenal hyperplasia, and salt-sensitive hypertension. In this study, we analyzed the GR+/em4 rat model heterozygously mutant for the deletion of exon 3, which encompasses the second zinc finger, including the domains of DNA binding, dimerization, and nuclear localization signals. On a standard diet, mutant rats exhibited a trend toward increased corticosterone levels and a normal systolic blood pressure and heart rate but presented with adrenal hyperplasia. They exhibited increased adrenal soluble epoxide hydroxylase (sEH), favoring an increase in less active polyunsaturated fatty acids. Indeed, a significant increase in nonactive omega-3 and omega-6 polyunsaturated fatty acids, such as 5(6)-DiHETrE or 9(10)-DiHOME, was observed with advanced age (10 versus 5 weeks old) and following a switch to a high-salt diet accompanied by salt-sensitive hypertension. In thoracic aortas, a reduced soluble epoxide hydrolase (sEH) protein abundance resulted in altered vascular reactivity upon a standard diet, which was blunted upon a high-salt diet. In conclusion, mutations in the GR affecting the ligand-binding domain as well as the dimerization domain resulted in deregulated GR signaling, favoring salt-sensitive hypertension in the absence of obvious mineralocorticoid excess. [ABSTRACT FROM AUTHOR]

[Display omitted] • Euphorbia factor L2 (EFL2) mitigated the inflammatory phenotype of gout attack. • EFL2 inhibited the MSU-induced release of IL-1β of macrophages. • EFL2 suppressed the NF-κB/NLRP3 pathway by binding to the glucocorticoid receptor. • EFL2 inhibited the assembly of the NLRP3 inflammasome specifically in MSU stimulation. • EFL2 alleviated MSU-induced lysosomal damage and endoplasmic reticulum stress. Euphorbia L. is a traditionally used herb and contains many newly identified compounds with novel chemical structures. Euphorbia factor L2 (EFL2), a diterpenoid derived from Euphorbia seeds, is reported to alleviate acute lung injury and arthritis by exerting anti-inflammatory effects. In this study, we aimed to test the therapeutic benefit and mechanisms of EFL2 in NLRP3 inflammasome-mediated gouty models and identified the potential molecular mechanism. A cell-based system was used to test the specific inhibitory effect of EFL2 on NLRP3-related inflammation. The gouty arthritis model and an air pouch inflammation model induced by monosodium urate monohydrate (MSU) crystals were used for in vivo experiments. Nlrp3-/- mice and in vitro studies were used for mechanistic exploration. Virtual molecular docking and biophysical assays were performed to identify the direct binding and regulatory target of EFL2. The inhibitory effect of EFL2 on inflammatory cell infiltration was determined by flow cytometry in vivo. The mechanism by which EFL2 activates the NLRP3 inflammasome signaling pathway was evaluated by immunological experiment and transmission electron microscopy. In vitro, EFL2 specifically reduced NLRP3 inflammasome-mediated IL-1β production and alleviated MSU crystal-induced arthritis, as well as inflammatory cell infiltration. EFL2 downregulated NF-κB phosphorylation and NLRP3 inflammasome expression by binding to glucocorticoid receptors. Moreover, EFL2 could specifically suppress the lysosome damage-mediated NLRP3 inflammasome activation process. It is expected that this work may be useful to accelerate the development of anti-inflammatory drugs originated from traditional herbs and improve therapeutics in gout and its complications. [ABSTRACT FROM AUTHOR]

In recent years, the clinical efficacy of medications for adenoid hypertrophy has been demonstrated. Topical nasal steroids have effects to shrink hypertrophic adenoids and improve symptoms of associated diseases. However, the mechanism which topical steroid administrations cause adenoid shrinkage remains unclear, herein, sensitivity for topical steroids in the mucosal epithelium of adenoids was evaluated histologically by comparing with tonsils. Histological analysis was performed on adenoids and tonsils removed from 32 pediatric patients with adenoid hypertrophy. In hematoxylin-eosin-stained specimens, the morphology of the mucosal epithelium and eosinophil infiltration were evaluated. The expression of the glucocorticoid receptor (GR), interleukin (IL)-4, and IL-25 in the mucosal epithelium was evaluated, and the staining intensity was scored as 0 (none), 1 (weak), and 2 (strong). The number of eosinophils and expression scores of GR, IL-4, and IL-25 were statistically compared between adenoids and tonsils and analyzed correlations with adenoids sizes. Adenoids were covered with ciliated epithelium, and eosinophils in the mucosal epithelium and submucosal area was higher than tonsils (p < 0.05). GR expression in the most superficial layer of the mucosal epithelium was observed in adenoids, and the expression intensity score was higher than that in tonsils (p < 0.05). IL-4 and IL-25 were more widely expressed in the mucosal epithelium of adenoids than in tonsils, and their expression intensity scores were also higher than in tonsils (p < 0.05). A correlation was found between adenoid size and the intensity of IL-25 expression in the adenoid epithelium (p < 0.05). Eosinophilic inflammations in adenoids mucosal epithelium could be one of etiology of adenoid hypertrophy, and the GR and eosinophilic inflammation in the adenoids mucosal epithelium might be target of topical nasal steroids to shrink hypertrophic adenoids. [ABSTRACT FROM AUTHOR]

[Display omitted] • Early life stress reduces acquisition and contextual recall of fear memories. • Early life stress alters immediate early gene expression after training and recall. • Early life stress effects on immediate early genes depend on brain region. • Colocalization of immediate early genes is altered after memory recall. • Adolescent treatment with RU486 does not mitigate effects of early life stress. The ability to learn and remember, which is fundamental for behavioral adaptation, is susceptible to stressful experiences during the early postnatal period, such as abnormal levels of maternal care. The exact mechanisms underlying these effects still remain elusive. This study examined whether early life stress (ELS) alters memory and brain activation patterns in male mice. Therefore, we examined the expression of the immediate early genes (IEGs) c-Fos and Arc in the dentate gyrus (DG) and basolateral amygdala (BLA) after training and memory retrieval in a fear conditioning task. Furthermore, we examined the potential of RU38486 (RU486), a glucocorticoid receptor antagonist, to mitigate ELS-induced memory deficits by blocking stress signalling during adolescence. Arc::dVenus reporter mice, which allow investigating experience-dependent expression of the immediate early gene Arc also at more remote time points, were exposed to ELS by housing dams and offspring with limited bedding and nesting material (LBN) between postnatal days (PND) 2–9 and trained in a fear conditioning task at adult age. We found that ELS reduced both fear acquisition and contextual memory retrieval. RU486 did not prevent these effects. ELS reduced the number of Arc::dVenus+ cells in DG and BLA after training, while the number of c-Fos+ cells were left unaffected. After memory retrieval, ELS decreased c-Fos+ cells in the ventral DG and BLA. ELS also altered the colocalization of c-Fos+ cells with Arc::dVenus+ cells in the ventral DG, possibly indicating impaired engram allocation in the ventral DG after memory retrieval. In conclusion, this study shows that ELS alters neuronal activation patterns after fear acquisition and retrieval, which may provide mechanistic insights into enduring impact of ELS on the processing of fear memories, possibly via changes in cell (co–) activation and engram cell allocation. [ABSTRACT FROM AUTHOR]

• Arsenic trioxide induced-EndMT could be reversed by Diosgenin pretreatment. • GR-IL-6 axis is an underlying mechanism for Diosgenin anti-EndMT effects. • Diosgenin is a viable medicine for arsenic cardiotoxicity clinical application. • Confirmed foreground to explore active ingredients recorded in ancient Chinese books. Arsenic trioxide (ATO), the first-line drug in treating acute premyelogenous leukemia, has the profound side effect of inducing endothelial mesenchymal transition (EndMT) and causing cardiac fibrosis. Diosgenin (DIO), a pharmaceutical compound found in Paris polyphylla, exhibits promising potential in safeguarding cardiovascular health by mitigating EndMT. This study aims to explore the role and mechanism of DIO in ATO-induced myocardial fibrosis to provide a novel therapeutic agent for ATO-induced cardiac fibrosis. Wistar rats were given DIO by gavage and ATO by tail vein. Cardiac function and fibrosis were evaluated by echocardiography and Masson's trichrome staining in rats. Human aortic endothelial cells (HAECs) were utilized to analyze ATO-induced EndMT in vitro. The cytoskeleton of HAECs was visualized using F-actin staining to observe cell morphology, while Dil-Ac-LDL staining was employed to assess cell functionality. EndMT-related factors (CD31 and α-SMA), glucocorticoid receptor (GR) and interleukin-6 (IL-6) were detected by immunofluorescence and Western blot in vivo and in vitro. Furthermore, GR was knocked down by si-GR, and IL-6 was blocked by IL-6 neutralizing antibody to verify their role in the effect of DIO on ATO-induced EndMT in HAECs. DIO exhibited significant efficacy in ATO-induced damage to both cardiac diastolic and systolic function, along with mitigating cardiac fibrosis. Additionally, DIO alleviated the loss of cytoskeletal anisotropy and enhanced the uptake of Dil-Ac-LDL in HAECs. Furthermore, it reversed the ATO-induced downregulation of endothelial-specific markers CD31 and GR, while suppressing the upregulation of mesenchymal markers α-SMA and IL-6, both in vivo and in vitro. Notably, the protective effect of DIO was compromised upon knockdown of GR, which also led to a reversal of DIO-induced IL-6 downregulation. Furthermore, the neutralization of IL-6 with specific antibodies abolished the ATO-induced changes related to EndMT. In this study, we clarified the protective effect of DIO on ATO-induced myocardial fibrosis against EndMT via the GR/IL-6 axis for the first time and provided a potential therapeutic agent for preventing heart damage caused by ATO. [Display omitted] [ABSTRACT FROM AUTHOR]

The glucocorticoid receptor (GR), including both alternative spliced isoforms (GRα and GRβ), has been implicated in the development of primary open-angle glaucoma (POAG) and iatrogenic glucocorticoid-induced glaucoma (GIG). POAG is the most common form of glaucoma, which is the leading cause of irreversible vision loss and blindness in the world. Glucocorticoids (GCs) are commonly used therapeutically for ocular and numerous other diseases/conditions. One serious side effect of prolonged GC therapy is the development of iatrogenic secondary ocular hypertension (OHT) and OAG (i.e., GC-induced glaucoma (GIG)) that clinically and pathologically mimics POAG. GC-induced OHT is caused by pathogenic damage to the trabecular meshwork (TM), a tissue involved in regulating aqueous humor outflow and intraocular pressure. TM cells derived from POAG eyes (GTM cells) have a lower expression of GRβ, a dominant negative regulator of GC activity, compared to TM cells from age-matched control eyes. Therefore, GTM cells have a greater pathogenic response to GCs. Almost all POAG patients develop GC-OHT when treated with GCs, in contrast to a GC responder rate of 40% in the normal population. An increased expression of GRβ can block GC-induced pathogenic changes in TM cells and reverse GC-OHT in mice. The endogenous expression of GRβ in the TM may relate to differences in the development of GC-OHT in the normal population. A number of studies have suggested increased levels of endogenous cortisol in POAG patients as well as differences in cortisol metabolism, suggesting that GCs may be involved in the development of POAG. Additional studies are warranted to better understand the molecular mechanisms involved in POAG and GIG in order to develop new disease-modifying therapies to better treat these two sight threatening forms of glaucoma. The purpose of this timely review is to highlight the pathological and clinical features of GC-OHT and GIG, mechanisms responsible for GC responsiveness, potential therapeutic options, as well as to compare the similar features of GIG with POAG.

Introduction: Today, humans live in a world surrounded by electromagnetic fields. Numerous studies have been conducted to discover the biological, physiological, and behavioral effects of electromagnetic fields on humans and animals. Given the biological similarities between monkeys and humans, The present research aimed to examine Visual Memory (VM), hormonal, genomic, and anatomic changes, in the male rhesus macaques exposed to an Extremely Low-Frequency Magnetic Field (ELF-MF). Methods: Four male rhesus macaques (Macaca mulatta) were used. For the behavioral tests, the animals should be fasting for 17 hours. For the tests such as visual memory, the animal’s cooperation was necessary. Using the radiation protocol, we exposed two monkeys to a 12-Hz electromagnetic field with a magnitude of 0.7 µT (electromagnetic radiation) four hours a day for a month. Before and after the exposure, a visual memory test was conducted using a coated device (visible reward) on a movable stand. Ten milliliters of blood was obtained from the femoral artery of each monkey, and half of it was used to examine cortisol serum levels using the MyBioSource kit (made in the USA). The other half of the blood was used to extract lymphocytes for assaying expressions of Glucocorticoid Receptor (GR) genes before and after radiation using the PCR method. Anatomic studies of the amygdala were carried out based on pre- and post-radiation Magnetic Resonance Imaging (MRI). Results: Research results indicated that visual memory in male primates increased significantly after exposure to the 12-Hz frequency. Hormonal analysis at the 12-Hz frequency showed a decrease in cortisol serum levels. However, visual memory and serum cortisol levels did not change considerably in male primates in the control group. There was no considerable amygdala volumetric difference after exposure to the 12-Hz frequency. The expression of the GR genes decreased in the 12-Hz group compared to the control group. Conclusion: In short, these results indicated that ELF might benefit memory enhancement because exposure to the 12-HZ ELF can enhance visual memory. This outcome may be due to a decrease in plasma cortisol and or expression of GR genes. Moreover, direct amygdala involvement in this regard cannot be recommended.

Glucocorticoids such as dexamethasone (Dex) are widely used to treat both acute and chronic inflammatory conditions. They regulate immune responses by dampening cell-mediated immunity in a glucocorticoid receptor (GR)-dependent manner, by suppressing the expression of pro-inflammatory cytokines and chemokines and by stimulating the expression of anti-inflammatory mediators. Despite its evident clinical benefit, the mechanistic underpinnings of the gene regulatory networks transcriptionally controlled by GR in a context-specific manner remain mysterious. Next generation sequencing methods such mRNA sequencing (RNA-seq) and Ribosome profiling (ribo-seq) provide tools to investigate the transcriptional and post-transcriptional mechanisms that govern gene expression. Here, we integrate matched RNA-seq data with ribo-seq data from human acute monocytic leukemia (THP-1) cells treated with the TLR4 ligand lipopolysaccharide (LPS) and with Dex, to investigate the global transcriptional and translational regulation (translational efficiency, ΔTE) of Dex-responsive genes. We find that the expression of most of the Dex-responsive genes are regulated at both the transcriptional and the post-transcriptional level, with the transcriptional changes intensified on the translational level. Overrepresentation pathway analysis combined with STRING protein network analysis and manual functional exploration, identified these genes to encode immune effectors and immunomodulators that contribute to macrophage-mediated immunity and to the maintenance of macrophage-mediated immune homeostasis. Further research into the translational regulatory network underlying the GR anti-inflammatory response could pave the way for the development of novel immunomodulatory therapeutic regimens with fewer undesirable side effects.

The complex mechanism by which stress can affect sensory processes such as hearing is still poorly understood. In a previous study, the mineralocorticoid (MR) and/or glucocorticoid receptor (GR) were deleted in frontal brain regions but not cochlear regions using a CaMKIIα-based tamoxifen-inducible CreERT2/loxP approach. These mice exhibit either a diminished (MRTMXcKO) or disinhibited (GRTMXcKO) auditory nerve activity. In the present study, we observed that mice differentially were (MRTMXcKO) or were not (GRTMXcKO) able to compensate for altered auditory nerve activity in the central auditory pathway. As previous findings demonstrated a link between central auditory compensation and memory-dependent adaptation processes, we analyzed hippocampal paired-pulse facilitation (PPF) and long-term potentiation (LTP). To determine which molecular mechanisms may impact differences in synaptic plasticity, we analyzed Arc/Arg3.1, known to control AMPA receptor trafficking, as well as regulators of tissue perfusion and energy consumption (NO-GC and GC-A). We observed that the changes in PPF of MRTMXcKOs mirrored the changes in their auditory nerve activity, whereas changes in the LTP of MRTMXcKOs and GRTMXcKOs mirrored instead the changes in their central compensation capacity. Enhanced GR expression levels in MRTMXcKOs suggest that MRs typically suppress GR expression. We observed that hippocampal LTP, GC-A mRNA expression levels, and ABR wave IV/I ratio were all enhanced in animals with elevated GR (MRTMXcKOs) but were all lower or not mobilized in animals with impaired GR expression levels (GRTMXcKOs and MRGRTMXcKOs). This suggests that GC-A may link LTP and auditory neural gain through GR-dependent processes. In addition, enhanced NO-GC expression levels in MR, GR, and MRGRTMXcKOs suggest that both receptors suppress NO-GC; on the other hand, elevated Arc/Arg3.1 levels in MRTMXcKOs and MRGRTMXcKOs but not GRTMXcKOs suggest that MR suppresses Arc/Arg3.1 expression levels. Conclusively, MR through GR inhibition may define the threshold for hemodynamic responses for LTP and auditory neural gain associated with GC-A.

IntroductionRepeated acute stress (RASt) is known to be associated with gastrointestinal dysfunctions. However, the mechanisms underlying these effects have not yet been fully understood. While glucocorticoids are clearly identified as stress hormones, their involvement in RASt-induced gut dysfunctions remains unclear, as does the function of glucocorticoid receptors (GR). The aim of our study was to evaluate the involvement of GR on RASt-induced changes in gut motility, particularly through the enteric nervous system (ENS).MethodsUsing a murine water avoidance stress (WAS) model, we characterized the impact of RASt upon the ENS phenotype and colonic motility. We then evaluated the expression of glucocorticoid receptors in the ENS and their functional impact upon RASt-induced changes in ENS phenotype and motor response.ResultsWe showed that GR were expressed in myenteric neurons in the distal colon under basal conditions, and that RASt enhanced their nuclear translocation. RASt increased the proportion of ChAT-immunoreactive neurons, the tissue concentration of acetylcholine and enhanced cholinergic neuromuscular transmission as compared to controls. Finally, we showed that a GR-specific antagonist (CORT108297) prevented the increase of acetylcholine colonic tissue level and in vivo colonic motility.DiscussionOur study suggests that RASt-induced functional changes in motility are, at least partly, due to a GR-dependent enhanced cholinergic component in the ENS.

BackgroundPrevious research has demonstrated that epigenetic changes in specific hypothalamic-pituitary-adrenal (HPA) genes may predict successful psychotherapy in post-traumatic stress disorder (PTSD). A recent Phase 3 clinical trial reported high efficacy of 3,4-methylenedioxymethamphetamine (MDMA)-assisted therapy for treating patients with severe PTSD compared to a therapy with placebo group (NCT03537014). This raises important questions regarding potential mechanisms of MDMA-assisted therapy. In the present study, we examined epigenetic changes in three key HPA axis genes before and after MDMA and placebo with therapy. As a pilot sub-study to the parent clinical trial, we assessed potential HPA epigenetic predictors for treatment response with genomic DNA derived from saliva (MDMA, n = 16; placebo, n = 7). Methylation levels at all 259 CpG sites annotated to three HPA genes (CRHR1, FKBP5, and NR3C1) were assessed in relation to treatment response as measured by the Clinician-Administered PTSD Scale (CAPS-5; Total Severity Score). Second, group (MDMA vs. placebo) differences in methylation change were assessed for sites that predicted treatment response.ResultsMethylation change across groups significantly predicted symptom reduction on 37 of 259 CpG sites tested, with two sites surviving false discovery rate (FDR) correction. Further, the MDMA-treatment group showed more methylation change compared to placebo on one site of the NR3C1 gene.ConclusionThe findings of this study suggest that therapy-related PTSD symptom improvements may be related to DNA methylation changes in HPA genes and such changes may be greater in those receiving MDMA-assisted therapy. These findings can be used to generate hypothesis driven analyses for future studies with larger cohorts.