Traditional Pediatric Massage Enhanced Hippocampal GR, BDNF and IGF-1 Expressions and Exerted an Anti-depressant Effect in an Adolescent Rat Model of CUMS-induced Depression.

This study aimed to investigate the anti-depressant effect of traditional pediatric massage (TPM) in adolescent rats and its possible mechanism. The adolescent depression model in rats was established by using chronic unpredictable mild stress (CUMS). All rats were randomly divided into five groups (seven per group), including the groups of control (CON), CUMS, CUMS with TPM, CUMS with back stroking massage (BSM) and CUMS with fluoxetine (FLX). The tests of sucrose preference, Morris water maze and elevated plus maze were used to evaluate depression-related behaviors. Plasma corticosterone (CORT) level was measured by ELISA. The gene and protein expressions of glucocorticoid receptor (GR), brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) were measured by RT-qPCR and IHC respectively. The results showed that CUMS induced depression-related behaviors in the adolescent rats, along with decreased weight gain and reduced hippocampal expressions of GR, IGF-1 and BDNF. TPM could effectively prevent depression-related behaviors in CUMS-exposed adolescent rats, manifested as increasing weight gain, sucrose consumption, ratio of open-arm entry, times of crossing the specific quadrant and shortening escape latency. TPM also decreased CORT level in plasma, together with enhancing expressions of GR, IGF-1 and BDNF in the hippocampus. These results may support the clinical application of TPM to prevent and treat adolescent depression.

Synephrine and Its Derivative Compound A: Common and Specific Biological Effects.

This review is focused on synephrine, the principal phytochemical found in bitter orange and other medicinal plants and widely used as a dietary supplement for weight loss/body fat reduction. We examine different aspects of synephrine biology, delving into its established and potential molecular targets, as well as its mechanisms of action. We present an overview of the origin, chemical composition, receptors, and pharmacological properties of synephrine, including its anti-inflammatory and anti-cancer activity in various in vitro and animal models. Additionally, we conduct a comparative analysis of the molecular targets and effects of synephrine with those of its metabolite, selective glucocorticoid receptor agonist (SEGRA) Compound A (CpdA), which shares a similar chemical structure with synephrine. SEGRAs, including CpdA, have been extensively studied as glucocorticoid receptor activators that have a better benefit/risk profile than glucocorticoids due to their reduced adverse effects. We discuss the potential of synephrine usage as a template for the synthesis of new generation of non-steroidal SEGRAs. The review also provides insights into the safe pharmacological profile of synephrine.

Crosstalk between glucocorticoid and mineralocorticoid receptors boosts glucocorticoid-induced killing of multiple myeloma cells.

The glucocorticoid receptor (GR) is a crucial drug target in multiple myeloma as its activation with glucocorticoids effectively triggers myeloma cell death. However, as high-dose glucocorticoids are also associated with deleterious side effects, novel approaches are urgently needed to improve GR action in myeloma. Here, we reveal a functional crosstalk between GR and the mineralocorticoid receptor (MR) that plays a role in improved myeloma cell killing. We show that the GR agonist dexamethasone (Dex) downregulates MR levels in a GR-dependent way in myeloma cells. Co-treatment of Dex with the MR antagonist spironolactone (Spi) enhances Dex-induced cell killing in primary, newly diagnosed GC-sensitive myeloma cells. In a relapsed GC-resistant setting, Spi alone induces distinct myeloma cell killing. On a mechanistic level, we find that a GR-MR crosstalk likely arises from an endogenous interaction between GR and MR in myeloma cells. Quantitative dimerization assays show that Spi reduces Dex-induced GR-MR heterodimerization and completely abolishes Dex-induced MR-MR homodimerization, while leaving GR-GR homodimerization intact. Unbiased transcriptomics analyses reveal that c-myc and many of its target genes are downregulated most by combined Dex-Spi treatment. Proteomics analyses further identify that several metabolic hallmarks are modulated most by this combination treatment. Finally, we identified a subset of Dex-Spi downregulated genes and proteins that may predict prognosis in the CoMMpass myeloma patient cohort. Our study demonstrates that GR-MR crosstalk is therapeutically relevant in myeloma as it provides novel strategies for glucocorticoid-based dose-reduction.

Electroacupuncture Ameliorates Hypothalamic‒Pituitary‒Adrenal Axis Dysfunction Induced by Surgical Trauma in Mice Through the Hypothalamic Oxytocin System.

Electroacupuncture (EA) can effectively reduce surgical stress reactions and promote postoperative recovery, but the mechanisms remain unclear. The present study aims to examine the effects of EA on the hyperactivity of the hypothalamic‒pituitary‒adrenal (HPA) axis and investigate its potential mechanisms. Male C57BL/6 mice were subjected to partial hepatectomy (HT). The results showed that HT increased the concentrations of corticotrophin-releasing hormone (CRH), corticosterone (CORT), and adrenocorticotropic hormone (ACTH) in the peripheral blood and upregulated the expression of CRH and glucocorticoid receptors (GR) proteins in the hypothalamus. EA treatment significantly inhibited the hyperactivity of the HPA axis by decreasing the concentration of CRH, CORT, and ACTH in peripheral blood and downregulating the expression of CRH and GR in the hypothalamus. Moreover, EA treatment reversed the HT-induced downregulation of oxytocin (OXT) and oxytocin receptor (OXTR) in the hypothalamus. Furthermore, intracerebroventricular injection of the OXTR antagonist atosiban blocked the effects of EA. Thus, our findings implied that EA mitigated surgical stress-induced HPA axis dysfunction by activating the OXT/OXTR signaling pathway.

Prenatal Hypoxia-Induced Adverse Reaction to Mild Stress is Associated with Depressive-Like Changes in the Glucocorticoid System of Rats.

The effects of prenatal hypoxia on neurodevelopment are predominantly associated with impaired maternal glucocorticoid stimulation of the fetus, which is "imprinted" in altered sensitivity of glucocorticoid reception in brain structures of offspring and can affect brain plasticity during lifespan. This study aimed to investigate response of the brain glucocorticoid system to mild stress (MS) in adult rats that survived prenatal severe hypoxia (PSH) on embryonic days 14-16. In response to MS the control (but not PSH) rats demonstrate increased corticosterone levels, a decrease in exploratory activity and increased anxiety. In the raphe nuclei of adult PSH rats the expression of glucocorticoid receptors (GR) is increased without changes in serotonin levels in comparison with the control. MS induces a decrease in GR expression accompanied by up-regulation of tryptophan hydroxylase 2 (tph2) and down-regulation of monoamine oxidase A (maoa) transcription in the raphe nuclei of both control and PSH groups. PSH also causes significant deviations in GR expression and GR-dependent transcription in the hippocampus, the medial prefrontal cortex, but not in the amygdala of rats. However, in response to MS, PSH rats demonstrate mild changes in their activity, while in control animals the MS-induced activity of the glucocorticoid system in these brain structures is similar to intact PSH animals. Impaired activity of the glucocorticoid system in the extrahypothalamic brain structures of PSH rats is accompanied by increase in the hypothalamic corticotropin-releasing hormone (CRH) levels in comparison with the control regardless of MS. Synthesis of proopiomelanocortin (POMC) and release of adrenocorticotropic hormone (ACTH) into the blood are decreased in response to MS in the pituitary of control rats, which demonstrates a negative glucocorticoid feedback mechanism. Meanwhile, in the pituitary of PSH rats reduced POMC levels were found regardless of MS. Thus, prenatal hypoxia causes depression-like patterns in the brain glucocorticoid system with adverse reaction to mild stressors.

Icariin Improves Glucocorticoid Resistance in a Murine Model of Asthma with Depression Associated with Enhancement of GR Expression and Function.

Icariin, a flavonoid glycoside isolated from Epimedium brevicornum, exerts a variety of biological activities. However, its effects on depression-induced glucocorticoid resistance in asthma and the underlying mechanisms have not been elucidated. In this study, a murine model of asthma with depression was established by exposure to ovalbumin combined with chronic unpredictable mild stress, and icariin was given orally during ovalbumin challenge and chronic unpredictable mild stress exposure. Depression-like behaviors were assessed by the open field test, forced swim test, and tail suspension test. The characteristic features of allergic asthma, including airway hyperreactivity, histopathology, inflammatory cytokine levels in bronchoalveolar lavage fluid, and immunoglobulin E and corticosterone levels in serum, were examined. Following splenocyte isolation in vitro, the inhibitory effects of corticosterone on the proliferation and cytokine secretion of splenocytes, glucocorticoid receptor DNA-binding activity, and expression of p-glucocorticoid receptor s226, glucocorticoid receptor α, and p-p38 mitogen-activated protein kinase in splenocytes were determined. We found that icariin had limited effects on depression-like behaviors, however, it markedly suppressed airway hyperresponsiveness, inflammatory infiltration in lung tissues, levels of interleukin-4, interleukin-5, and interleukin-6 in bronchoalveolar lavage fluid, and immunoglobulin E in serum. Furthermore, icariin improved the inhibitory effects of corticosterone on lipopolysaccharide-stimulated splenocytes, increased the glucocorticoid receptor expression and glucocorticoid receptor DNA-binding activity, and inhibited the phosphorylation of glucocorticoid receptors S226 and p38 mitogen-activated protein kinase. Taken together, icariin improved glucocorticoid resistance in a murine model of asthma with depression associated with enhancement of glucocorticoid receptor function and glucocorticoid receptor expression, and its effects on the glucocorticoid receptor function were related to decreased phosphorylation of glucocorticoid receptors S226 and p38 mitogen-activated protein kinase.

FKBP5 intron 7 methylation is associated with higher anxiety proneness and smaller right thalamus volume in adolescents.

Dysregulation of stress response systems may mediate the detrimental effects of childhood trauma (CT) on mental health. FKBP5 regulates glucocorticoid receptor sensitivity and exerts pleiotropic effects on intracellular signaling, neurobiology and behavior. We investigated whether CT, alone and in combination with rs1360780 genotype, is associated with altered FKBP5 methylation and whether CT-associated methylation profiles are associated with anxiety proneness (AP) and structural brain volumes. Ninety-four adolescents completed the Childhood Trauma Questionnaire, and a composite AP score was generated from the Childhood Anxiety Sensitivity Index and the State-Trait Anxiety Inventory-Trait measure. Mean methylation values for 12 regulatory regions and 25 individual CpG sites were determined using high-accuracy measurement via targeted bisulfite sequencing. FKBP5 rs1360780 genotype and structural MRI data were available for a subset of participants (n = 71 and n = 75, respectively). Regression models revealed an inverse association between methylation of three intron 7 CpG sites (35558438, 35558566 and 35558710) and right thalamus volume. CpG35558438 methylation was positively associated with AP scores. Our data indicate that an intron 7 methylation profile, consistent with lower FKBP5 expression and elevated high sensitivity glucocorticoid receptor levels, is associated with higher AP and smaller right thalamus volume. Research into the mechanisms underlying the intron 7 methylation-thalamus volume relationship, and whether it confers increased risk for long-term psychopathology by altering the regulatory threshold of stress responding, is required.

Apoptosis and glucocorticoid-related genes mRNA expression is modulated by coenzyme Q10 supplementation during in vitro maturation and vitrification of bovine oocytes and cumulus cells.

Oocyte in vitro maturation (IVM) and vitrification procedures lead to detrimental effects on the overall oocyte quality. The addition of antioxidants during IVM, such as the coenzyme Q10 (Q10), has been demonstrated to positively impact on the cumulus-oocyte complexes due to its role in protection from oxidative damage and modulating gene transcription. Furthermore, glucocorticoids (GC) regulate gene transcription, energy metabolism and apoptosis during the early steps of reproduction. In this sense, most GC actions are mediated by the glucocorticoid receptor (NR3C1), a transcription factor. However, the specific roles of GC in ovarian physiology and oocyte maturation are still unknown. In this regard, a better knowledge on the expression of GC-related and apoptosis-related genes during IVM and cryopreservation procedures could potentially benefit the refinement of assisted reproductive techniques in the bovine species. The present study aims to explore the expression of NR3C1 mRNA in fresh and vitrified bovine oocytes and cumulus cells in response to Q10 (50 µM), and the effect of cortisol addition (0.25 µM, 0.5 µM) on the expression of NR3C1. We also studied the mRNA expression of NR3C1-related genes belonging to the GC regulation pathway, such as hydroxysteroid dehydrogenases (HSD11B1; HSD11B2), immunophilins (FKBP4; FKBP5), signal transducers and activators of transcription (STAT3; STAT5A), the mineralocorticoid receptor (NR3C2), and to the apoptosis pathway, such as the anti- (BCL2) and pro-apoptotic (BAX) mRNA transcripts in oocytes and cumulus cells 1) after IVM, and 2) after vitrification, both in presence or absence of Q10 supplementation during IVM. Our results show that there is an increase in the NR3C1 receptor expression after vitrification of oocytes, but not after exogenous cortisol supplementation during IVM. In addition, Q10 reduces the mRNA expression of HSD11B1 and FKBP5 in oocytes at levels of immature oocytes (HSD11B1 mRNA expression also in cumulus cells), and the BAX:BCL2 ratio mRNA expression. After vitrification in the presence of Q10, HSD11B2 mRNA expression increases in cumulus cells, while HSD11B1 and BAX:BCL2 mRNA expression decreases significantly both in oocytes and cumulus cells. In conclusion, our results show for the first time the effect of IVM, vitrification and Q10 supplementation on the mRNA relative expression of GC-related and apoptosis genes, and the effect of vitrification in the protein expression of NR3C1.

Hypothalamic Kisspeptin Neurons Regulates Energy Metabolism and Reproduction Under Chronic Stress.

Background: Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, affecting energy homeostasis and reproduction. The aim of this study was to investigate whether stress affected energy metabolism and reproduction through the glucocorticoid receptor on Kisspeptin neurons in the hypothalamus. Methods: Four groups included control group, chronic restraint stress group, Kisspeptin specific glucocorticoid receptor knock out group (KGRKO) and KGRKO+stress group. Body weight, food intake, estrous cycle of female mice, serum sex hormone levels, serum corticosterone and prolactin, Kisspeptin expression in the hypothalamus were measured. Results: The restraint stress group showed a significant weight loss compared with the control group. KGRKO+restraint stress group had a reduced weight loss, suggesting that restraint stress might partially affect the energy metabolism through GR on Kisspeptin neurons. In terms of reproductive function, the restraint stress group and the KGRKO+restraint stress group showed missing pre-estrus period or prolonged estrous cycles. Serum LH and FSH in KGRKO + restraint stress group decreased significantly compared with KGRKO group. However, no significant difference in the level of serum testosterone was observed. After restraint stress, the levels of serum cortisol and prolactin in male and female mice were significantly higher than the control group, and the hypothalamus Kiss1 gene mRNA expression and Kisspeptin protein expression were significantly decreased. Conclusion: Chronic restraint stress induced weight loss and negative changes in reproduction, which were partially mediated by glucocorticoid receptor on Kisspeptin neurons in the hypothalamus.

Xiaoyaosan inhibits neuronal apoptosis by regulating the miR-200/NR3C1 signaling in the prefrontal cortex of chronically stressed rats.

BACKGROUND: Depression is a prevalent emotion disorder which is thought to be due to neuronal structural alterations and/or functional impairment within specific brain regions. Several studies have shown that microRNAs are involved in the pathogenesis of depression. As a Chinese herbal formula, Xiaoyaosan (XYS) could have antidepressive effects, although the mechanisms associated with microRNAs are poorly understood. PURPOSE: In this study, we investigated whether inhibition of the miR-200a/b-3p/NR3C1 pathway in the prefrontal cortex is involved in the anti-neuronal apoptosis and anti-stress effects of XYS and then further delineated the underlying mechanism. METHODS: To evaluate the efficacy of XYS in relieving stress behaviors and altering the expression of miRNAs involved in the regulation of these behaviors in vivo, a chronic unpredictable mild stress (CUMS) rodent model and RNA-seq were performed. Primary cortical neurons were used to evaluate the molecular function of miR-200a/b-3p and detect the in vitro neuroprotective function of paeoniflorin, which is one of the main components of XYS. To investigate the function of miR-200a/b-3p in stress behaviors, stereotactic microinjection of AAV2/9-Syn-miR-200a/b-3p was performed to deliver the treatment to the rat mPFC. RESULTS: XYS reduced the anxiety and depression-like behaviors associated with chronic stress and reduced the expression of miR-200a/b-3p and neuronal apoptosis in the prefrontal cortex (PFC). The overexpression of miR-200a/b-3p in primary cortical neurons reduced the expression of the target gene NR3C1, increased the protein expression of cleaved caspase-3 and Bax, and decreased the anti-apoptotic protein Bcl-2. One of the active ingredients of XYS, paeoniflorin, can inhibit miR-200a/b-3p-mediated apoptosis of primary neurons and abnormal expression of apoptosis-related proteins. After overexpressing miR-200a/b-3p in vivo (vmPFC), the rats eventually showed significant anxiety-like behaviors similar to those caused by chronic stress. CONCLUSION: Our findings indicate that XYS can inhibit the CUMS-induced expression of miR-200a/b-3p, regulate miR-200a/b-3p/NR3C1 signaling in the PFC caused by chronic stress, and reduce neuronal apoptosis and stress-related behaviors.

[Effect of wheat-grain moxibustion on the expression of 5-HT and cortisol in the serum, and MR and GR in the hippocampus in rats with hypothyroidism complicated with depression].

OBJECTIVE: To observe the effect of wheat-grain moxibustion on behavior, 5-hydroxytryptamine (5-HT) and cortisol in the serum, mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the hippocampus in rats with hypothyroidism complicated with depression, and to explore the possible mechanism of wheat-grain moxibustion on improving depression in rats with hypothyroidism. METHODS: A total of 32 SPF SD rats were randomly divided into a blank group, a model group, a medication group and a wheat-grain moxibustion group, 8 rats in each group. Except for the blank group, the rats in the remaining groups were treated with intragastric administration of 0.1% propylthiouracil (PTU) suspension at 1 mL/100 g, once a day for 4 weeks to establish the rat model of hypothyroidism, and whether the rats were accompanied with depression-like behavior determined through behavioristics evaluation. The rats in the medication group were intervened with euthyrox at 0.9 mL/100 g, once a day, for 4 weeks; the rats in the wheat-grain moxibustion group were treated with wheat-grain moxibustion at "Dazhui" (GV 14), "Mingmen" (GV 4), "Shenshu" (BL 23) and "Pishu" (BL 20), 7 cones each acupoint, once a day, six times a week for 4 weeks. After the intervention, the depression status was observed by behavioristics test; the contents of thyroid stimulating hormone (TSH), total thyroxine (TT4), 5-HT and cortisol in the serum were detected by ELISA; the protein expressions of MR and GR in hippocampus were detected by Western blot; the expressions of MR mRNA and GR mRNA in the hippocampus were detected by real-time PCR. RESULTS: Before the intervention, compared with the blank group, the scores of open field test (OFT) were decreased and the immobility time of tail suspension test (TST) was prolonged (P<0.05); the serum TSH contents were increased and TT4 contents were decreased (P<0.01) in the other three groups. After the intervention, compared with the model group, the vertical score of OFT was increased and the immobility time of forced swimming test (FST) was prolonged in the medication group (P<0.05), while the scores of three items of OFT were increased (P<0.05, P<0.01), and the immobility time of FST and TST was shortened in the wheat-grain moxibustion group (P<0.01, P<0.05). Compared with the medication group, the immobility time of TST and FST in the wheat-grain moxibustion group was shorter (P<0.05, P<0.01). Compared with the blank group, in the model group, the contents of serum TSH and cortisol were increased (P<0.01, P<0.001), while the contents of serum TT4 and 5-HT were decreased (P<0.01, P<0.001). Compared with the model group, the contents of serum TT4 and 5-HT were increased, while the contents of serum TSH and cortisol were decreased in the medication group and wheat-grain moxibustion group (P<0.01, P<0.05). Compared with the blank group, the protein and mRNA expression of MR, GR in the hippocampus in the model group was decreased (P<0.01, P<0.05, P<0.001); compared with the model group, the protein and mRNA expression of MR in the hippocampus in the medication group were increased (P<0.05), and the protein expression of MR, GR and mRNA expression of MR in the hippocampus in the wheat-grain moxibustion group were increased (P<0.05, P<0.01). Compared with the medication group, the expression of MR mRNA in the wheat-grain moxibustion group was increased (P<0.05). CONCLUSION: Wheat-grain moxibustion could significantly improve thyroid function and depression in rats with hypothyroidism. Its mechanism may be related to up-regulating the protein and mRNA expression of MR and GR in the hippocampus, and then affecting the expression of serum cortisol and 5-HT.

Xiaoyao powder alleviates the hippocampal neuron damage in chronic unpredictable mild stress-induced depression model rats in hippocampus via connexin 43Cx43/glucocorticoid receptor/brain-derived neurotrophic factor signaling pathway.

Xiaoyao Powder (XYP) has been widely applied in China to treat stress-related illnesses, such as migraine, depression, Parkinson's disease, insomnia, and hypertension. Herein, this study aims to explore the effect of XYP on chronic unpredictable mild stress (CUMS)-induced depression and its underlying mechanisms. CUMS-induced depression rat models were established, they were subsequently randomly divided and treated with various conditions. Results of this study indicated that supplementation of XYP observably abolished CUMS-induced hippocampal damage and serum corticosterone (CORT) elevation. In mechanism, we discovered that CUMS induction could cause a prominent downregulation in glucocorticoid receptor (GR), phosphorylated-GR (p-GR), connexin 43 (Cx43), and brain-derived neurotrophic factor (BDNF), a remarkable upregulation in c-Src. While the introduction of XYP could reverse the changes in all of these indicators mediated by CUMS. Furthermore, we proved that Cx43 could interact with GR, and the protective effect of XYP on hippocampal neurons is realized by up-regulating GR. Summarized, this study indicated that XYP could ameliorate hippocampal neuron damage in CUMS-induced depression model rats through acting on Cx43/GR/BDNF axis.

Electroacupuncture and moxibustion-like stimulation activate the cutaneous and systemic hypothalamic-pituitary-adrenal axes in the rat.

OBJECTIVE: To determine whether electroacupuncture (EA) or moxibustion-like stimulation (MLS) can affect the cutaneous and/or systemic hypothalamic-pituitary-adrenal (HPA) axes. METHODS: Rats were divided into Control, EA, 37°C MLS and 43.5°C MLS groups. EA and MLS were performed at bilateral ST36 or LI4. The expression of corticotropin-releasing factor (CRF), adrenocorticotropic hormone (ACTH) and the glucocorticoid receptor (GR) was detected in local cutaneous tissues at the site of ST36 and LI4 by immunohistochemical staining. In addition, levels of CRF, ACTH and corticosterone (CORT) in cutaneous tissue and plasma were determined. RESULTS: Cutaneous expression of CRF, ACTH and GR significantly increased after EA at ST36, while only GR increased after 43.5°C MLS at ST36. The results of EA and MLS at LI4 were in parallel with those at ST36. In plasma, compared with the control group, the level of CORT increased after EA at ST36, while both ACTH and CORT were markedly increased after 43.5°C MLS. For LI4, plasma CRF and CORT increased after EA, while the levels of all three hormones increased following 43.5°C MLS. Notably, compared with the effect of EA, 43.5°C MLS at ST36 produced a more substantial increase in plasma CORT, and 43.5°C MLS at LI4 induced a more dramatic increase in plasma CRF and CORT. CONCLUSION: Both EA and 43.5°C MLS can activate the cutaneous and systemic HPA axes of the rat. EA tended to activate the local cutaneous HPA, while 43.5°C MLS was more likely to activate the systemic HPA axis.

Increased Hippocampal Glucocorticoid Receptor Expression and Reduced Anxiety-Like Behavior Following Tuina in a Rat Model With Allergic Airway Inflammation.

OBJECTIVE: This study aimed to explore the influence mechanism of Tuina on anxiety-like behavior in immature rats with allergic airway inflammation (AAI). METHODS: A total of 27 Sprague-Dawley male rats (aged ∼5 weeks) were divided randomly into control, AAI, and AAI with Tuina groups (9 rats per group). The anxiety-like behavior was assessed by an open field test and elevated plus-maze test. Allergic airway inflammation was assessed based on the pathological score of the lung, plasma ovalbumin-specific immunoglobulin E, interleukin 4, interleukin 5, and tumor necrosis factor-alpha levels. Glucocorticoid receptor (GR) messenger RNA and protein expression in the hippocampus and lung were detected by polymerase chain reaction and immunohistochemistry, respectively. Meanwhile, corticotropin-releasing hormone (CRH) messenger RNA in the hypothalamus, the plasma levels of adrenocorticotropic hormone and corticosterone were also determined respectively by polymerase chain reaction and enzyme-linked immunosorbent assay for hypothalamic-pituitary-adrenal axis (HPA) function. RESULTS: The AAI group had obvious anxiety-like behavior and hyperactive HPA axis, along with decreased GR expression in the hippocampus and lung. Following Tuina, AAI and the anxiety-like behavior were efficiently reduced, and the hyperactivity of HPA axis was efficiently inhibited, along with enhanced GR expression in the hippocampus and lung. CONCLUSION: Glucocorticoid receptor expression in the hippocampus and lung was enhanced, and anxiety-like behavior was reduced following Tuina in rats with AAI.

Dysfunction of the hypothalamic­pituitary­adrenal axis in male rat offspring with prenatal food restriction: Fetal programming of hypothalamic hyperexcitability and poor hippocampal feedback.

Prenatal food restriction (PFR) induces dysfunction of the hypothalamic­pituitary­adrenal (HPA) axis in the adult offspring. The aim of the present study was to identify the underlying mechanism of this process. Pregnant rats were placed on a restricted diet between gestational day 11 and 21. The offspring were fed with a high­fat diet and were subjected to unpredictable chronic stress (UCS) from postnatal week 17 to 20. A higher serum corticosterone (CORT) level was observed in the PFR fetuses. Although lower arginine vasopressin (AVP), hippocampal vesicular glutamate transporter 2 (vGLUT2) and glutamic acid decarboxylase 65 (GAD65) mRNA expression levels were detected in the hippocampi of PFR fetuses, the ratio of the mRNA expression levels of vGLUT2 and GAD65 was higher compared with that of the controls, which was accompanied by histopathological and ultrastructural abnormalities of both the hypothalamus and hippocampus. However, there were no marked changes in the hippocampal expression levels of glucocorticoids receptor (GR) and mineralocorticoids receptor (MR) or the ratio of MR/GR ratio. After the fetuses had matured, lower serum CORT and adrenocorticotropic hormone (ACTH) levels were observed in PFR rats without UCS when compared with the control. A higher rise rate of serum ACTH was also observed after UCS when compared with that in rats without UCS. Furthermore, the hypothalamic mRNA expression level of corticotrophin­releasing hormone (CRH) was lower in PFR rats without UCS, while expression levels of CRH, AVP, GAD65 and vGLUT2 were enhanced after UCS when compared with the control, accompanied by an increased vGLUT2/GAD65 expression ratio. MR mRNA expression was lower, and GR mRNA expression was higher in the hippocampus of the PFR rats without UCS when compared with the control. However, the mRNA expression levels of both MR and GR in the PFR rats were higher compared with those of the control after UCS, which was accompanied histopathological changes in the dentate gyrus, cornu ammonis (CA1) and CA3 areas. In summary, it was suggested that PFR induced fetal alterations of the HPA axis manifesting as hypothalamic hyperexcitability and poor hippocampal feedback, which persisted to adulthood and affected the behavior of the rat offspring.

Effect of wheat-grain moxibustion on the expression of 5-HT and cortisol in the serum, and MR and GR in the hippocampus in rats with hypothyroidism complicated with depression / 中国针灸

OBJECTIVE@#To observe the effect of wheat-grain moxibustion on behavior, 5-hydroxytryptamine (5-HT) and cortisol in the serum, mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the hippocampus in rats with hypothyroidism complicated with depression, and to explore the possible mechanism of wheat-grain moxibustion on improving depression in rats with hypothyroidism.@*METHODS@#A total of 32 SPF SD rats were randomly divided into a blank group, a model group, a medication group and a wheat-grain moxibustion group, 8 rats in each group. Except for the blank group, the rats in the remaining groups were treated with intragastric administration of 0.1% propylthiouracil (PTU) suspension at 1 mL/100 g, once a day for 4 weeks to establish the rat model of hypothyroidism, and whether the rats were accompanied with depression-like behavior determined through behavioristics evaluation. The rats in the medication group were intervened with euthyrox at 0.9 mL/100 g, once a day, for 4 weeks; the rats in the wheat-grain moxibustion group were treated with wheat-grain moxibustion at "Dazhui" (GV 14), "Mingmen" (GV 4), "Shenshu" (BL 23) and "Pishu" (BL 20), 7 cones each acupoint, once a day, six times a week for 4 weeks. After the intervention, the depression status was observed by behavioristics test; the contents of thyroid stimulating hormone (TSH), total thyroxine (TT4), 5-HT and cortisol in the serum were detected by ELISA; the protein expressions of MR and GR in hippocampus were detected by Western blot; the expressions of MR mRNA and GR mRNA in the hippocampus were detected by real-time PCR.@*RESULTS@#Before the intervention, compared with the blank group, the scores of open field test (OFT) were decreased and the immobility time of tail suspension test (TST) was prolonged (P<0.05); the serum TSH contents were increased and TT4 contents were decreased (P<0.01) in the other three groups. After the intervention, compared with the model group, the vertical score of OFT was increased and the immobility time of forced swimming test (FST) was prolonged in the medication group (P<0.05), while the scores of three items of OFT were increased (P<0.05, P<0.01), and the immobility time of FST and TST was shortened in the wheat-grain moxibustion group (P<0.01, P<0.05). Compared with the medication group, the immobility time of TST and FST in the wheat-grain moxibustion group was shorter (P<0.05, P<0.01). Compared with the blank group, in the model group, the contents of serum TSH and cortisol were increased (P<0.01, P<0.001), while the contents of serum TT4 and 5-HT were decreased (P<0.01, P<0.001). Compared with the model group, the contents of serum TT4 and 5-HT were increased, while the contents of serum TSH and cortisol were decreased in the medication group and wheat-grain moxibustion group (P<0.01, P<0.05). Compared with the blank group, the protein and mRNA expression of MR, GR in the hippocampus in the model group was decreased (P<0.01, P<0.05, P<0.001); compared with the model group, the protein and mRNA expression of MR in the hippocampus in the medication group were increased (P<0.05), and the protein expression of MR, GR and mRNA expression of MR in the hippocampus in the wheat-grain moxibustion group were increased (P<0.05, P<0.01). Compared with the medication group, the expression of MR mRNA in the wheat-grain moxibustion group was increased (P<0.05).@*CONCLUSION@#Wheat-grain moxibustion could significantly improve thyroid function and depression in rats with hypothyroidism. Its mechanism may be related to up-regulating the protein and mRNA expression of MR and GR in the hippocampus, and then affecting the expression of serum cortisol and 5-HT.

Crabp1 Modulates HPA Axis Homeostasis and Anxiety-like Behaviors by Altering FKBP5 Expression.

Retinoic acid (RA), the principal active metabolite of vitamin A, is known to be involved in stress-related disorders. However, its mechanism of action in this regard remains unclear. This study reports that, in mice, endogenous cellular RA binding protein 1 (Crabp1) is highly expressed in the hypothalamus and pituitary glands. Crabp1 knockout (CKO) mice exhibit reduced anxiety-like behaviors accompanied by a lowered stress induced-corticosterone level. Furthermore, CRH/DEX tests show an increased sensitivity (hypersensitivity) of their feedback inhibition in the hypothalamic-pituitary-adrenal (HPA) axis. Gene expression studies show reduced FKBP5 expression in CKO mice; this would decrease the suppression of glucocorticoid receptor (GR) signaling thereby enhancing their feedback inhibition, consistent with their dampened corticosterone level and anxiety-like behaviors upon stress induction. In AtT20, a pituitary gland adenoma cell line elevating or reducing Crabp1 level correspondingly increases or decreases FKBP5 expression, and its endogenous Crabp1 level is elevated by GR agonist dexamethasone or RA treatment. This study shows, for the first time, that Crabp1 regulates feedback inhibition of the the HPA axis by modulating FKBP5 expression. Furthermore, RA and stress can increase Crabp1 level, which would up-regulate FKBP5 thereby de-sensitizing feedback inhibition of HPA axis (by decreasing GR signaling) and increasing the risk of stress-related disorders.

Feeding Rhythm-Induced Hypothalamic Agouti-Related Protein Elevation via Glucocorticoids Leads to Insulin Resistance in Skeletal Muscle.

Circadian phase shifts in peripheral clocks induced by changes in feeding rhythm often result in insulin resistance. However, whether the hypothalamic control system for energy metabolism is involved in the feeding rhythm-related development of insulin resistance is unknown. Here, we show the physiological significance and mechanism of the involvement of the agouti-related protein (AgRP) in evening feeding-associated alterations in insulin sensitivity. Evening feeding during the active dark period increased hypothalamic AgRP expression and skeletal muscle insulin resistance in mice. Inhibiting AgRP expression by administering an antisense oligo or a glucocorticoid receptor antagonist mitigated these effects. AgRP-producing neuron-specific glucocorticoid receptor-knockout (AgRP-GR-KO) mice had normal skeletal muscle insulin sensitivity even under evening feeding schedules. Hepatic vagotomy enhanced AgRP expression in the hypothalamus even during ad-lib feeding in wild-type mice but not in AgRP-GR-KO mice. The findings of this study indicate that feeding in the late active period may affect hypothalamic AgRP expression via glucocorticoids and induce skeletal muscle insulin resistance.

Prenatal and Postnatal Methyl-Modulator Intervention Corrects the Stress-Induced Glucocorticoid Response in Low-Birthweight Rats.

Low body weight at birth has been shown to be a risk factor for future metabolic disorders, as well as stress response abnormalities and depression. We showed that low-birthweight rats had prolonged high blood corticosterone levels after stress exposure, and that an increase in Gas5 lncRNA, a decoy receptor for glucocorticoid receptors (GRs), reduces glucocorticoid responsiveness. Thus, we concluded that dampened pituitary glucocorticoid responsiveness disturbed the glucocorticoid feedback loop in low-birthweight rats. However, it remains unclear whether such glucocorticoid responsiveness is suppressed solely in the pituitary or systemically. The expression of Gas5 lncRNA increased only in the pituitary, and the intact induction of expression of the GR co-chaperone factor Fkbp5 against dexamethasone was seen in the liver, muscle, and adipose tissue. Intervention with a methyl-modulator diet (folate, VB12, choline, betaine, and zinc) immediately before or one week after delivery reversed the expression level of Gas5 lncRNA in the pituitary of the offspring. Consequently, it partially normalized the blood corticosterone levels after restraint stress exposure. In conclusion, the mode of glucocorticoid response in low-birthweight rats is impaired solely in the pituitary, and intervention with methyl-modulators ameliorates the impairment, but with a narrow therapeutic time window.

Vitamin D Regulates the Expression of Glucocorticoid Receptors in Blood of Severe Asthmatic Patients.

PURPOSE: Vitamin D (VitD) deficiency is a significant public health concern in many areas around the globe and has been associated with many immune-mediated diseases, including asthma. Severe asthma has been linked to a decreased glucocorticoid receptor (GR) ratio (GR-α/GR-ß ratio), indicating steroid hyporesponsiveness. Using a combination of in silico and in vivo approaches, we aimed to explore the immunomodulatory effect of VitD on asthmatic patients diagnosed with hypovitaminosis D. METHODS: In silico tools were used to identify the regulatory effect of VitD supplementation on GR genes. We measured the expression levels of GR-α and the inactive isoform, GR-ß, in the blood of adult asthmatics diagnosed with hypovitaminosis D before and after VitD supplementation. Moreover, the blood levels of inflammatory cytokines associated with asthma severity were determined. RESULTS: Using an in silico approach, we identified specific genes commonly targeted by VitD as well as corticosteroids, the mainstay of asthma therapy. NR3C1 gene encoding GR was found to be significantly upregulated on Th2 CD4 cells and NK cells. Interestingly, blood expression level of NR3C1 was lower in severe asthmatics compared to nonsevere asthmatics and healthy controls, while the blood level of VitD receptor (VDR) was higher. Upon VitD supplementation of severe asthmatic patients, there was a significant increase in the blood levels of GR-α with no change in GR-ß mRNA expression. VitD supplementation also suppressed the blood levels of IL-17F and IL-4. CONCLUSION: VitD may enhance steroid responsiveness by upregulating the expression of steroid receptor GR-α.