ACTH-producing thymic neuroendocrine tumor initially presenting as psychosis: A case report and literature review.

A 32-year-old woman was referred to our hospital because of severe psychosis and was found to have an ectopic ACTH-producing thymic neuroendocrine tumor. Laboratory data revealed an elevated serum cortisol and plasma ACTH level, hypokalemia, and metabolic alkalosis. Chest computed tomography (CT) revealed an anterior mediastinal mass and multiple pulmonary nodules. As the patient was unable to communicate because of her consciousness disturbance, she was managed with artificial ventilation and deep sedation. Metyrapone and potassium supplementation were administered, and steroid psychosis gradually improved. Thoracic surgery was performed and the histopathological diagnosis was thymic neuroendocrine tumor with positive anti-ACTH immunohistochemical staining. Here we present details of the case and review the literature.

Sex differences in the regulation of brain IL-1ß in response to chronic stress.

Elevations in brain interleukin-1 beta (IL-1ß) during chronic stress exposure have been implicated in behavioral and cognitive impairments associated with depression and anxiety. Two critical regulators of brain IL-1ß production during times of stress are glucocorticoids and catecholamines. These hormones work in opposition to one another to inhibit (via glucocorticoid receptors) or stimulate (via beta-adrenergic receptors: ß-AR) IL-1ß production. While chronic stress often heightens both corticosterone and catecholamine levels, it remains unknown as to how chronic stress may affect the "yin-yang" balance between adrenergic stimulation and glucocorticoid suppression of brain IL-1ß. To investigate this further, male and female rats underwent 4 days of stress exposure or served as non-stressed controls. On day 5, animals were administered propranolol (ß-AR antagonist), metyrapone (a glucocorticoid synthesis inhibitor), vehicle, or both drugs and brain IL-1ß mRNA was measured by rtPCR in limbic brain areas. In males, administration of propranolol had no effect on IL-1ß expression in non-stressed controls but significantly reduced IL-1ß in the hippocampus and amygdala of chronically stressed animals. In females, propranolol significantly reduced IL-1ß in the amygdala and hypothalamus of both control and stressed rats. In male rats, metyrapone treatment significantly increased IL-1ß mRNA regardless of stress treatment in all brain areas, while in female rats metyrapone only increased IL-1ß in the hypothalamus. Interestingly, propranolol treatment blocked the metyrapone-induced increase in brain IL-1ß indicating the increase in brain IL-1ß following metyrapone treatment was due to increase ß-AR activation. Additional studies revealed that metyrapone significantly increases norepinephrine turnover in the hypothalamus and medial prefrontal cortex in male rats and that microglia appear to be the cell type contributing to the production of IL-1ß. Overall, data reveal that stress exposure in male rats affects the regulation of brain IL-1ß by the norepinephrine-ß-AR pathway, while stress had no effect in the regulation of brain IL-1ß in female rats.

5-Hydroxytryptamine 1A (5HT1A) receptors mediate increases in plasma glucose independent of corticosterone.

Hypothalamic 5HT1A receptors play an important role in the regulation of satiety, glycemia and endocrine status. In the present study, 8-OH-DP administered centrally and peripherally to C57/Bl6 mice and plasma glucose insulin and corticosterone were evaluated. In these studies, dose and time dependent increases in glucose and corticosterone were observed while no alterations in insulin were seen. The increases in plasma corticosterone were prevented by prior central or peripheral administration of LY426965, a specific 5HT1A antagonist. Intracerebroventricular coadministration of a 5HT1A antagonist with 8-OH-DPAT prevented the increase in plasma glucose establishing this response as a centrally mediated response in mice. Given that increases in plasma corticosterone are associated with increases in plasma glucose, we conducted experiments to determine if increased plasma corticosterone was the mechanism by which 8-OH-DPAT increased plasma glucose. Prior administration of the glucocorticoid antagonist mifepristone did not affect the increase in plasma glucose produced by 8-OH-DPAT. Prior administration of the glucocorticoid synthesis inhibitor, metyrapone, reduced basal corticosterone and the concentrations of corticosterone associated with 8-OH-DPAT administration. However, metyrapone administration did not affect the increases in plasma glucose. Therefore, 5HT1A receptors regulate glucose through brain mechanisms, but not through regulation of the hypophyseal-pituitary axis. Antagonism of brain 5HT1A receptors may enable discovery of novel antidiabetic agents.

Corticosterone-activated mineralocorticoid receptor contributes to salt-induced sympathoexcitation in pressure overload mice.

Abstract We previously reported that pressure overload (PO) activates the hypothalamic mineralocorticoid receptor (MR) and angiotensin II type 1 receptor (AT1R). Moreover, salt intake further activates the hypothalamic MR and AT1R, resulting in salt-induced sympathoexcitation. However, the mechanism underlying this pathway activation in response to a high salt intake remains unknown. Although the role of aldosterone is extensively examined as a ligand for MR, corticosterone is able to bind to MR. Therefore, we hypothesized that corticosterone contributes to salt-induced sympathoexcitation in PO-mice. Four weeks after aortic banding to produce PO-mice, or a sham operation for controls, the mice were fed a high-salt diet for an additional 4 weeks. Compared to Sham-mice, the expression levels of hypothalamic MR, serum glucocorticoid-induced kinase 1 (a marker of MR activity) and AT1R increased in PO-mice. Salt intake further increased the expression levels of these proteins only in PO-mice with the increases in sympathetic activity evaluated on the basis of the excretion of 24-h urinary norepinephrine excretion. Bilateral adrenalectomy or the intraperitoneal infusion of metyrapone, a corticosterone synthase inhibitor, attenuated salt-induced sympathoexcitation via inhibition of the hypothalamic MR and AT1R activity. These adrenalectomy-induced alterations disappeared after corticosterone replacement therapy. We also found decreased expression levels of 11ß-hydroxysteroid dehydrogenase type 2, suggesting that corticosterone is apt to bind to MR. These results indicate that salt intake in PO-mice causes sympathoexcitation via, at least in part, corticosterone-induced MR and AT1R activation in the hypothalamus.

New prospects for drug treatment in Cushing disease.

Hypercortisolism induced by Cushing disease causes high morbidity and mortality. The treatment of choice is pituitary surgery, but it often fails to achieve cure, and other treatment modalities (radiotherapy, bilateral adrenalectomy) may therefore be required. If these treatments are not effective or while waiting for their results, hypercortisolism should be controlled with drugs. The classical drug treatments are those that act by inhibiting cortisol secretion by the adrenal gland (ketoconazole, metyrapone, mitotane, etomidate). The preliminary results of a new drug (LCI699) which is a potent enzyme inhibitor of cortisol secretion have been reported. A clinical trial of the safety and efficacy of mifepristone, a glucocorticoid receptor antagonist, has just been published. The drugs deserving more attention today are those with a direct action on the tumor by inhibiting ACTH secretion: somatostatin analogues (pasireotide), dopamine agonists (cabergoline), PPAR-γ, and retinoic acid. A special review is made of the available clinical trials with pasireotide and cabergoline.

Mitotane, metyrapone, and ketoconazole combination therapy as an alternative to rescue adrenalectomy for severe ACTH-dependent Cushing's syndrome.

CONTEXT: Mitotane is highly effective in the long-term management of Cushing's syndrome but has a slow onset of action. Mitotane combined with fast-acting steroidogenesis inhibitors might avoid the need for emergency bilateral adrenalectomy in patients with severe hypercortisolism. OBJECTIVE: Our objective was to assess the efficacy and safety of combination therapy with mitotane, metyrapone, and ketoconazole in severe ACTH-dependent Cushing's syndrome. PATIENTS, DESIGN, AND SETTING: Eleven patients with severe Cushing's syndrome participated in this follow-up study in a tertiary referral hospital. INTERVENTIONS: High-dose therapy combining mitotane (3.0-5.0 g/24 h), metyrapone (3.0-4.5 g/24 h), and ketoconazole (400-1200 mg/24 h) was initiated concomitantly. Twenty-four-hour urinary free cortisol (UFC) excretion (normal values 10-65 µg/24 h) was monitored. RESULTS: Data are reported as medians (range). All 11 patients experienced a marked clinical improvement. UFC excretion fell rapidly from 2737 µg/24 h (range 853-22,605) at baseline to 50 µg/24 h (range 18-298) (P = 0.001) within 24-48 h of treatment initiation and remained low to normal on the combination therapy. In seven patients, metyrapone and ketoconazole were discontinued after 3.5 months (range 3.0-6.0) of combination therapy, and UFC excretion remained controlled by mitotane monotherapy (UFC 17 µg/24 h, range 5-85; P = 0.016). Five patients became able to undergo etiological surgery and are presently in remission. Four of them recovered normal adrenal function after mitotane discontinuation. Adverse effects were tolerable, consisting mainly of gastrointestinal discomfort and a significant rise in total cholesterol and γ-glutamyl transferase levels (P = 0.012 and P = 0.002, respectively). CONCLUSIONS: When surgical treatment for severe ACTH-dependent Cushing's syndrome is not feasible, combination therapy with mitotane, metyrapone, and ketoconazole is an effective alternative to bilateral adrenalectomy, a procedure associated with significant morbidity and permanent hypoadrenalism.

Effects of endogenous glucocorticoid secretion on the interleukin-6 response to bacterial endotoxin in pregnant and non-pregnant rats.

Glucocorticoids (GCs) are released in response to immune activation by the bacterial endotoxin, lipopolysaccharide (LPS). However, GC secretion in response to immune activation and other stressors is attenuated at term of pregnancy. GCs are important modulators of the immune response, and both pro- and anti-inflammatory effects are described. Here, we examined whether GC secretion in response to LPS is maintained in earlier pregnancy before term, and investigated the role of endogenous GCs in modulating LPS-induced circulating cytokines, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), in pregnant compared to non-pregnant female rats. Plasma corticosterone (Cort) and ACTH responses to LPS were well maintained in pregnant rats at embryonic days 15/16 (E15/16) and E18/19 compared to non-pregnant rats. At E19, maternal LPS administration increased fetal plasma Cort and decreased testosterone in male fetuses. In non-pregnant animals, pretreatment with the GC synthesis inhibitor, metyrapone, inhibited the LPS-induced increase in IL-6, and the IL-6 response was restored by Cort replacement, indicating that LPS induction of IL-6 is Cort-dependent. In E15 pregnant animals, metyrapone had no effect on LPS-induced IL-6 levels, indicating that LPS-induction of IL-6 is not dependent on Cort. These contrasting patterns of IL-6 induction in non-pregnant and pregnant animals were reflected in levels of hypothalamic Socs3 mRNA, an indicator of IL-6 signaling pathway activation. In both non-pregnant and pregnant rats, LPS-induced plasma TNF-α responses were inhibited by metyrapone but not re-instated by Cort replacement. It is suggested that altered GC regulation of IL-6 may be required to sustain specialized functions of IL-6 during pregnancy.

Somatic and neuroendocrine responses to standard and biologically salient acoustic startle stimuli in monkeys.

The startle response, a simple defensive response to a sudden stimulus signaling proximal threat, has been well studied in rodents and humans, but has been rarely examined in monkeys. The first goal of the present studies was to develop a minimally immobilizing startle measurement paradigm and validate its usefulness by testing two core features of the startle response (habituation and graded responsivity) in squirrel monkey subjects. Two different types of startle stimuli were used: standard broad-band noise bursts, and species-specific alarm vocalizations ("yaps") which are elicited in response to threat in both wild and captive animals. The second goal of the present studies was to test whether yaps produce enhanced startle responsivity due to their increased biological salience compared to simple, non-biologically relevant noise bursts. The third goal of the present studies was to evaluate the hypothalamic-pituitary-adrenal (HPA) axis response to startle stimuli, as little is known about the stress-activating role of startle stimuli in any species. These experiments determined that the whole-body startle response in relatively unrestrained squirrel monkeys habituates across repeated stimulus presentations and is proportional to stimulus intensity. In addition, differential habituation was observed across biologically salient vs. standard acoustic startle stimuli. Responses to "yaps" were larger initially but attenuated more rapidly over trials. Responses to "yaps" were also larger in the early subepochs of the response window but then achieved a lower level than responses to noise bursts in the later subepochs. Finally, adrenocorticotropic hormone and cortisol concentrations were significantly elevated above baseline after startle stimuli presentation, though monkeys did not exhibit differential HPA axis responses to the two types of startle stimuli. The development of monkey startle methodology may further enhance the utility of this paradigm in translational studies of human stress-related psychiatric disorders.

Anti-inflammatory effect of bee venom on antigen-induced arthritis in rabbits: influence of endogenous glucocorticoids.

AIM OF THE STUDY: This study assessed the involvement of endogenous glucocorticoids (GCs) in the anti-arthritic properties of bee venom (BV) on antigen-induced arthritis (AIA) in rabbits. MATERIALS AND METHODS: BV (1.5-6 microg/kg/day) was injected for 7 days before AIA induction, whereas the control group received sterile saline. The total and differential leukocyte count, PGE(2) levels in synovial fluid and synovial membrane cell infiltrate were evaluated. The contribution of GCs to BV action was assessed in rabbits treated with BV plus metyrapone, an inhibitor of GC synthesis, or RU-38 486, a steroid antagonist. RESULTS: Treatment with BV (1.5 microg/kg/day) reduced the leukocyte count and PGE(2) level (18571+/-1909 cells/mm(3) and 0.49+/-0.05 ng/mL, respectively) as well as the cellular infiltrate compared with the control group (40968+/-5248 cells/mm(3) and 2.92+/-0.68 ng/mL, p<0.05). The addition of metyrapone to BV treatment completely reversed the inhibition of AIA, whereas RU-38 486 was ineffective. CONCLUSION: Our data show that bee venom treatment prevents the development of antigen-induced arthritis in rabbits through the action of GCs.

Metyrapone blunts stress-induced hyperthermia and increased locomotor activity independently of glucocorticoids and neurosteroids.

Metyrapone, a cytochrome P(450) inhibitor used to inhibit corticosterone synthesis, triggers biological markers of stress and also reduces stress-induced anxiety-like behaviors. To address these controversial effects, 6 separate investigations were carried out. In a first set of investigations, abdominal temperature (T(abd)), spontaneous locomotor activity (A(S)) and electroencephalogram (EEG) were recorded in freely moving rats treated with either saline or 150 mg kg(-1) metyrapone. An increase in T(abd) and A(S) occurred in saline rats, while, metyrapone rats exhibited an immediate decrease, both variables returning to basal values 5h later. Concomitantly, the EEG spectral power increased in the gamma and beta 2 bands and decreased in the alpha frequency band, and the EMG spectral power increased. This finding suggests that metyrapone depressed stress-induced physiological response while arousing the animal. In a second step, restraint stress was applied 5h after injection. Metyrapone significantly blunted the stress-induced T(abd) and A(S) rise, without affecting the brain c-fos mRNA increase. Corticosterone (5 and 40 mg kg(-1)) injected concomitantly to metyrapone failed to reverse the observed metyrapone-induced effects in T(abd) and A(S). Finasteride (50 mg kg(-1)), which blocks neurosteroid production, was also unable to block these effects. In conclusion, metyrapone acutely reduced stress-induced physiological response in freely behaving rats independently from glucocorticoids and neurosteroids.

Gene expression changes in the hypothalamus provide evidence for regionally-selective changes in IL-1 and microglial markers after acute stress.

Recent work from our laboratory and others has shown that certain stressors increase expression of the pro-inflammatory cytokine interleukin-1beta (IL-1) in the hypothalamus. The first goal of the following studies was to assess the impact of acute stress on other key inflammatory factors, including both cytokines and cell surface markers for immune-derived cells resident to the CNS in adult male Sprague Dawley rats exposed to intermittent footshock (80 shocks, 90 s variable ITI, 5 s each). While scattered changes in IL-6 and GFAP were observed in the hippocampus and cortex, we found the hypothalamus to be exquisitely sensitive to the effects of footshock. At the level of the hypothalamus, mRNA for IL-1 and CD14 were significantly increased, while at the same time CD200R mRNA was significantly decreased. A subsequent experiment demonstrated that propranolol (20mg/kg i.p.) blocked the increase in IL-1 and CD14 mRNA observed in the hypothalamus, while the decrease in CD200R was unaffected by propranolol. Interestingly, inhibition of glucocorticoid synthesis via injection of metyrapone (50mg/kg s.c.) plus aminoglutethimide (100mg/kg s.c.) increased basal IL-1 mRNA and augmented IL-1 and CD14 expression provoked by footshock. Injection of minocycline, a putative microglial inhibitor, blocked the IL-1 response to footshock, while CD14 and CD200R were unaffected. Together, these gene expression changes (i) provide compelling evidence that stress may provoke neuroinflammatory changes that extend well beyond isolated changes in a single cytokine; (ii) suggest opposing roles for classic stress-responsive factors (norepinephrine and corticosterone) in the modulation of stress-related neuroinflammation; (iii) indicate microglia within the hypothalamus may be key players in stress-related neuroinflammation; and (iv) provide a potential mechanism (increased CD14) by which acute stress primes reactivity to later immune challenge.

Glucocorticoid inhibition in the treatment of depression: can we think outside the endocrine hypothalamus?

BACKGROUND: Major depressive disorder affects a substantial percentage of the U.S. population, and can be highly debilitating. Selective serotonin reuptake inhibitors are commonly prescribed to treat depression, but may not be as effective for more severe or persistent depression. METHODS: The authors review data concerning the effects of corticosteroid synthesis inhibitors (CSIs) in the management of depressive disorders, present a hypothesis as to their possible mechanisms of action based on recent data suggesting synergistic effects of glucocorticoids on extrahypothalamic corticotropin-releasing hormone (CRH), and consider alternative hypotheses. Published reports evaluating the efficacy of CSIs in treating depression are reviewed and presented in light of recent findings regarding actions of glucocorticoids on the central CRH system. RESULTS: Results from open label and double-blind studies by several groups have indicated that CSIs may be efficacious or of adjunctive value in some patients with depression, including those refractory to other agents; however, there is a need for more controlled studies. Several lines of data suggest that the mechanism of action of these agents may not be solely a function of inhibition of adrenal cortisol production. CONCLUSIONS: The authors propose that CSIs may be efficacious in part by reducing glucocorticoid enhancement of CRH action in neurons of the central nucleus of the amygdala and other structures outside the endocrine hypothalamus. Possible effects of systemically administered CSIs on glucocorticoid receptor regulation, neuroactive steroids, and classical monoamine systems are also discussed. We conclude that available clinical data suggest a potential role for CSIs in the management of depressive disorders, especially major depression with psychotic features.

Endogenous cortisol suppression with metyrapone enhances acoustic startle in healthy subjects.

Previous human studies have shown that excess cortisol sufficient to fully occupy central nervous system (CNS) corticosteroid receptors may reduce startle eye blink. The present study tested whether cortisol depletion and the resulting reduction in activity of CNS corticosteroid receptors has the opposite effect. In a single-blind, placebo-controlled, randomized study, eye blink EMG responses to 105 dB acoustic startle stimuli were assessed in 25 healthy subjects who received oral metyrapone (1500 mg) to suppress endogenous cortisol production, while 24 controls received oral placebo. As expected, metyrapone significantly reduced salivary cortisol, indicating effective endogenous cortisol suppression. Startle eye blink responses were significantly increased in the metyrapone group. Short-term habituation of the startle reflex was not different between groups. Our results suggest that startle is enhanced during depletion of cortisol. This effect may be mediated by CNS mechanisms controlling cortisol feedback.

Hypocortisolemic clamp unmasks jointly feedforward- and feedback-dependent control of overnight ACTH secretion.

BACKGROUND: ACTH secretion is under hypothalamic stimulatory (feedforward) and adrenal inhibitory (feedback) control. HYPOTHESIS: Assessment of overnight ACTH secretion during a hypocortisolemic clamp will permit the estimation of changing feedforward and feedback. SUBJECTS: Seven healthy men. INTERVENTIONS: An oral dose of placebo (PLAC), metyrapone (METY, 3 g), or ketoconazole (KTCZ, 1.2 g) was given at midnight (MN) to block glucocorticoid synthesis. Plasma ACTH was sampled every 10 min (MN to 0800 h). ANALYSIS: Variable-waveform deconvolution analysis of ACTH secretion and approximate entropy (ApEn) analysis of pattern regularity. RESULTS: Compared with PLAC, administration of METY and KTCZ reduced morning cortisol concentrations by >or=77 and 54% respectively (P<0.001). Hypocortisolemia elevated pulsatile ACTH secretion by 8.2- (METY) and 5.3-fold (KTCZ; both P<0.001). Basal ACTH secretion rose by 3.4-fold under METY-induced cortisol depletion (P=0.020). ACTH secretory-burst shape and half-life were stable. ApEn of ACTH release declined overnight (P=0.021) and with the drug (P=0.001), denoting enhanced feedforward coordination. CONCLUSION: The combined data predict overnight amplification and coordination of hypothalamic feedforward drive onto ACTH release. Therefore, disruption of either mechanism might contribute to clinical pathophysiology, such as late-day elevations of cortisol output in fasting, alcoholism, depression, or aging.

[Characteristics of uptake, transport and efflux of Z- and E-ajoenes in Caco-2 cell monolayers in vitro].

The characteristics of uptake, transepithelial transport and efflux of Z- and E-ajoenes isolated from the bulbs of Allium sativum were studied. A human colon cell model Caco-2 cell monolayers in vitro cultured had been applied to study the characteristics of uptake, transepithelial transport and efflux of Z- and E-ajoenes. The quantitative determination of Z- and E-ajoenes was performed by high-performance liquid chromatography. Z- and E-Ajoenes can be detected only in the apical side and can be metabolized, but both compounds can not be transported from apical-to-basolateral and basolateral-to-apical directions in cultured Caco-2 cell monolayers. The metabolism of Z- and E-ajoenes in Caco-2 cell monolayers can be partially inhibited by vitamin C as an anti-oxidant, metyrapone as an inhibitor to subtype CYP3A of cytochrome P450 drug metabolism enzymes, and sodium azide as an inhibitor to ATP production. It is shown that neither Z-ajoene nor E-ajoene can pass through Caco-2 cell monolayers, and that they can be metabolized by the cells. The metabolism might be in correlation with cytochrome P450 drugs metabolism enzymes in Caco-2 cell monolayers.

Sound conditioning protects hearing by activating the hypothalamic-pituitary-adrenal axis.

Sound conditioning primes the auditory system to low levels of acoustic stimuli and reduces damage caused by a subsequent acoustic trauma. This priming activates the HPA axis resulting in the elevation of plasma corticosterone with a consequent upregulation of glucocorticoid receptors (GR) in the cochlea and the paraventricular nucleus (PVN) of the hypothalamus in the mouse. This protective effect is blocked by adrenalectomy or pharmacological treatment with RU486 + metyrapone. Sound conditioning prevents GR down-regulation induced by acoustic trauma and subsequently enhances GR activity in spiral ganglion neurons. Increased SRC-1 expression, triggered by sound conditioning, positively correlates with the upregulation of GR in the cochlea. These findings will help to define the cellular mechanisms responsible for protecting the auditory system from hearing loss by sound conditioning.

Characteristics of uptake, transport and efflux of Z- and E-ajoenes in Caco-2 cell monolayers in vitro / 药学学报

The characteristics of uptake, transepithelial transport and efflux of Z- and E-ajoenes isolated from the bulbs of Allium sativum were studied. A human colon cell model Caco-2 cell monolayers in vitro cultured had been applied to study the characteristics of uptake, transepithelial transport and efflux of Z- and E-ajoenes. The quantitative determination of Z- and E-ajoenes was performed by high-performance liquid chromatography. Z- and E-Ajoenes can be detected only in the apical side and can be metabolized, but both compounds can not be transported from apical-to-basolateral and basolateral-to-apical directions in cultured Caco-2 cell monolayers. The metabolism of Z- and E-ajoenes in Caco-2 cell monolayers can be partially inhibited by vitamin C as an anti-oxidant, metyrapone as an inhibitor to subtype CYP3A of cytochrome P450 drug metabolism enzymes, and sodium azide as an inhibitor to ATP production. It is shown that neither Z-ajoene nor E-ajoene can pass through Caco-2 cell monolayers, and that they can be metabolized by the cells. The metabolism might be in correlation with cytochrome P450 drugs metabolism enzymes in Caco-2 cell monolayers.

[Effects of blockage of hypothalamic-pituitary-adrenal cortex axis by metyrapone and Jiawei Xiaoyao Pills on immune system in mice exposed to chronic emotional stress].

OBJECTIVE: To explore the effects of Jiawei Xiaoyao Pills (JWXYP) on immune system of mice exposed to chronic emotional stress, and to compare its effects with blockage of hypothalamic-pituitary-adrenal cortex axis (HPAA) by metyrapone. METHODS: Eighty male mice were randomly divided into eight groups: normal saline-treated group, normal saline-treated stress group, JWXYP-treated group, JWXYP-treated stress group, metyrapone-treated group, metyrapone-treated stress group, metyrapone and JWXYP-treated group and metyrapone and JWXYP-treated stress group. A box of electrical shock was used to induce chronic emotional stress in mice. The metyrapone was applied to blocking the HPAA. The JWXYP, a classical formula of traditional Chinese medicine, which can alleviate the damages caused by chronic emotional stress, was also used to compare its effects with that of metyrapone. The body weight, thymus index, rate of apoptosis in thymus, serum concentration of glucocorticoid, activity of natural killer cells, lymphocyte transmission rate of mice were all measured and examined after interventions. The pathological changes of thymus tissue were observed. RESULTS: The thymus index, activity of natural killer cells and lymphocyte transmission rate were lower while the rate of apoptosis in thymus as well as the severity degree of pathological damages in thymus tissue were increased in the different drug-treated stress groups as compared with those in the corresponding drug-treated groups without stress. The activity of natural killer cells and the lymphocyte transmission rate induced by lipopolysaccharide were increased while the serum concentration of glucocorticoid and the severity degree of pathological damages in thymus tissue were decreased in both the metyrapone-treated stress group and JWXYP-treated stress group as compared with those in the normal saline-treated stress group. The combined intervention of metyrapone and JWXYP did not show better effects on immune system in mice exposed to chronic emotional stress than single metyrapone or JWXYP intervention. CONCLUSION: Blockage of HPAA by metyrapone intervention shows a significant protective effect on immune system in mice exposed to chronic emotional stress, and the JWXYP also exerts a similar protective effect against damages induced by chronic emotional stress. The HPAA may be one of the action targets of protective effects of JWXYP.

NF-kappaB mediated glucocorticoid response in the inner ear after acoustic trauma.

The inner ear of humans and experimental animals demonstrate an abundance of glucocorticoid receptors (GR). Glucocorticoids (GC) are widely used to treat different hearing disorders; yet the mechanisms of GC action on the inner ear are unknown. We demonstrate how GR can directly modulate hearing sensitivity in response to a moderate acoustic trauma that results in a hearing loss (10-30 dB). The GC agonist (dexamethasone) and the drugs (metyrapone + RU 486) showed opposing effects on hearing threshold shifts. GC agonist (dexamethasone) decreased the hearing threshold whereas pre-treatment with a GC synthesis inhibitor (metyrapone) in combination with a GR antagonist (RU 486) exacerbated auditory threshold shifts (25-60 dB) after acoustic trauma with statistically significant increase in GR mRNA and GR protein compared with the vehicle and acoustic trauma group. Acoustic trauma caused a significant increase in the nuclear transport of NF-kappaB, whereas pre-treatment with the drugs (metyrapone and RU 486) blocked NF-kappaB nuclear transport into spiral ganglion nuclei. An NF-kappaB inhibitor, pyrrolidine dithiocarbamate ammonium blocked the trauma-induced translocation of NF-kappaB and resulted in a hearing loss (45-60) dB. These results indicate that several factors define the responsiveness of the inner ear to GC, including the availability of ligand or receptor, and the nuclear translocation of GR and NF-kappaB. These findings will further our understanding of individual GC responsiveness to steroid treatment, and will help improve the development of pharmaceuticals to selectively target GR in the inner ear for individuals with increased sensitivity to acoustic trauma.

Decreased response of plasma cortisol to intravenous metyrapone in ocular hypertension and primary open-angle glaucoma.

PURPOSE: To determine if there is a difference in response to metyrapone, which blocks the conversion of 11-deoxycortisol to cortisol in the adrenal gland between normals and ocular hypertensives (OH) plus primary open-angle glaucomas (POAG) without pigmented angles. METHODS: Intravenous metyrapone was given to 20 normals and 15 ocular hypertensives plus primary open-angle glaucomas without pigmented angles. Blood samples were obtained at 4, 6, and 8 hours after administration of intravenous metyrapone for analyses of 11-deoxycortisol and cortisol. RESULTS: The ocular hypertensives plus primary open-angle glaucoma group showed significantly lower cortisol values compared with the normal group at 6 hours (P = 0.002) but not at 4 or 8 hours. There were no significant differences between the two groups for 11-deoxycortisol values at 4, 6, or 8 hours. The percent decrease of plasma cortisol from baseline was significantly greater for the ocular hypertensives plus open-angle glaucoma group compared with the normals at 4 hours (P = 0.010) and 6 hours (P = 0.0004). Significant negative correlations were observed for the total group of subjects between levels of plasma cortisol at 6 hours and intraocular pressure, worse eye (P = 0.029), percent area of cupping, worse eye (P = 0.045), pallor, worse eye (P = 0.001), and visual field loss, worse eye (P = 0.048), so that the less the plasma cortisol, the greater the abnormality of the glaucomatous parameters. Multivariate analyses with the 6-hour plasma cortisol level as the dependent variable showed that the only significant (P = 0.0004) independent variable was the percent area of pallor, worse eye, associated with a smaller level of plasma cortisol at 6 hours. Similarly, the multiple regression models using the percent change from baseline of the 6-hour plasma cortisol value showed a significant association of larger percent decreases of plasma cortisol in the ocular hypertensives plus open-angle glaucoma compared with the normals. CONCLUSIONS: The ocular hypertensives plus primary open-angle glaucoma subjects show greater adrenal inhibition to metyrapone in the synthesis of cortisol from 11-deoxycortisol compared with normals. This observation suggests an adrenal abnormality in the ocular hypertensive plus primary open-angle glaucoma subjects.