Attenuation of house dust mite Dermatophagoides farinae-induced airway allergic responses in mice by dehydroepiandrosterone is correlated with down-regulation of TH2 response

Aging-Related Mechanisms Contribute to Corticosteroid Insensitivity in Elderly Asthma

Asthma in elderly populations is an increasing health problem that is accompanied by diminished lung function and frequent exacerbations. As potent anti-inflammatory drugs, corticosteroids are commonly used to reduce lung inflammation, improve lung function, and manage disease symptoms in asthma. Although effective for most individuals, older patients are more insensitive to corticosteroids, making it difficult to manage asthma in this population. With the number of individuals older than 65 continuing to increase, it is important to understand the distinct mechanisms that promote corticosteroid insensitivity in the aging lung. In this review, we discuss corticosteroid insensitivity in asthma with an emphasis on mechanisms that contribute to persistent inflammation and diminished lung function in older individuals.

Low serum levels of dehydroepiandrosterone sulfate and testosterone in Albanian female patients with allergic disease

Evidence from several unrelated animal models and some studies conducted in humans, points to the immunomodulatory effects of androgens on various components of the immune system, especially on allergic disorders. This study evaluated the serum concentrations of sex hormones in women with allergy. For this purpose, blood samples were obtained from 78 participants in order to detect serum IgE concentrations, total testosterone, estradiol, progesterone, and DHEA-S. The majority of the subjects (54) in the study were consecutive patients with doctor-diagnosed allergic pathologies: 32 with allergic rhinitis, 10 with asthma and rhinitis, and 12 with skin allergies. In addition, 24 healthy volunteers were included in the research as the control group. The average age of the subjects was 32.54 years (SD ± 11.08 years, range between 4-59 years). All participants stated that they had not used any medical treatment to alleviate any of their symptoms prior to taking part in the research. They all underwent skin-prick tests for common aero-allergens, which was used as criterion for subject selection. Hence, the subjects were selected if they reacted positively to at least one aero-allergen. Their height and weight were measured in order to calculate the BMI. As a result, statistically significant differences between controls and allergic women in serum concentrations of androgens (testosterone, p = 0.0017; DHEA-S, p = 0.04) were found, which lead to the conclusion that the concentration of total serum testosterone and DHEA-S was lower in female patients with allergic diseases compared to controls.

Dehydroepiandrosterone Supplementation May Benefit Women with Asthma Who Have Low Androgen Levels: A Pilot Study

Introduction

Among individuals with severe asthma, FEV₁ is low in individuals with low dehydroepiandrosterone (DHEA) sulfate (DHEAS) levels. In the Severe Asthma Research Program (SARP), no women with DHEAS > 200 μg/dL had an FEV₁ < 60% predicted. DHEA has benefited patients with COPD and pulmonary hypertension in small trials. Therefore, we hypothesized that DHEA supplementation may improve FEV₁ in asthmatic women with low DHEAS.

Methods

Premenopausal, nonsmoking, otherwise healthy women, 18-50 years old, with mild or moderate asthma and baseline FEV₁ > 60% predicted received 100 mg DHEA orally every 12 h for 2 weeks. Spirometry and DHEAS were measured at the initial visit and 2 weeks later, after completion of DHEA treatment. Based on our previous work, the primary outcome variable for this pilot study was post-albuterol spirometry in the low-DHEAS group. Subjects also continued their other routine asthma management.

Results

Serum DHEAS increased with DHEA treatment in women with starting DHEAS < 200 µg/dL: this increase was from 71 ± 23 to 725 ± 295 µg/dL (n = 10; p = 0.0001). The increase in the high-DHEAS group was smaller. Post-albuterol FEV₁ increased by 51 mL, from 3.026 ± 0.5 to 3.077 ± 0.49 L (n = 10; p = 0.034 by paired t test, significant after Bonferroni), in women with low DHEAS. In the high-DHEAS group (baseline DHEAS ≥ 200 µg/dl), post-albuterol FEV₁ did not change significantly (n = 3, p = NS). Three subjects were excluded: one had comorbid COPD, one could not perform spirometry, and one did not take the DHEA. There were no adverse effects of DHEA treatment in this trial.

Conclusions

Endocrine treatments (corticosteroids) are a mainstay of anti-inflammatory management for moderate and severe asthma. Their use has improved asthma outcomes. Androgens also reduce airway inflammation and promote airway smooth muscle relaxation, but are rarely used clinically for asthma treatment. Our results suggest that the over-the-counter steroid DHEA may improve lung function in asthma outcomes among women with DHEAS < 200 ug/dL.

Immunological Processes Driving IgE Sensitisation and Disease Development in Males and Females

IgE sensitisation has increased significantly over the last decades and is a crucial factor in the development of allergic diseases. IgE antibodies are produced by B cells through the process of antigen presentation by dendritic cells, subsequent differentiation of CD4⁺ Th2 cells, and class switching in B cells. However, many of the factors regulating these processes remain unclear. These processes affect males and females differently, resulting in a significantly higher prevalence of IgE sensitisation in males compared to females from an early age. Before the onset of puberty, this increased prevalence of IgE sensitisation is also associated with a higher prevalence of clinical symptoms in males; however, after puberty, females experience a surge in the incidence of allergic symptoms. This is particularly apparent in allergic asthma, but also in other allergic diseases such as food and contact allergies. This has been partly attributed to the pro- versus anti-allergic effects of female versus male sex hormones; however, it remains unclear how the expression of sex hormones translates IgE sensitisation into clinical symptoms. In this review, we describe the recent epidemiological findings on IgE sensitisation in male and females and discuss recent mechanistic studies casting further light on how the expression of sex hormones may influence the innate and adaptive immune system at mucosal surfaces and how sex hormones may be involved in translating IgE sensitisation into clinical manifestations.

Dehydroepiandrosterone (DHEA): hypes and hopes

Dehydroepiandrosterone (DHEA) and its sulfated form dehydroepiandrosterone sulfate (DHEAS) are the most abundant circulating steroid hormones in humans. In animal studies, their low levels have been associated with age-related involuntary changes, including reduced lifespan. Extrapolation of animal data to humans turned DHEA into a 'superhormone' and an 'anti-aging' panacea. It has been aggressively marketed and sold in large quantities as a dietary supplement. Recent double-blind, placebo-controlled human studies provided evidence to support some of these claims. In the elderly, DHEA exerts an immunomodulatory action, increasing the number of monocytes, T cells expressing T-cell receptor gamma/delta (TCRγδ) and natural killer (NK) cells. It improves physical and psychological well-being, muscle strength and bone density, and reduces body fat and age-related skin atrophy stimulating procollagen/sebum production. In adrenal insufficiency, DHEA restores DHEA/DHEAS and androstenedione levels, reduces total cholesterol, improves well-being, sexual satisfaction and insulin sensitivity, and prevents loss of bone mineral density. Normal levels of CD4+CD25(hi) and FoxP3 (forkhead box P3) are restored. In systemic lupus erythematosus, DHEA is steroid-sparing. In an unblinded study, it induced remission in the majority of patients with inflammatory bowel disease. DHEA modulates cardiovascular signalling pathways and exerts an anti-inflammatory, vasorelaxant and anti-remodelling effect. Its low levels correlate with increased cardiovascular disease and all-cause mortality. DHEA/DHEAS appear protective in asthma and allergy. It attenuates T helper 2 allergic inflammation, and reduces eosinophilia and airway hyperreactivity. Low levels of DHEAS accompany adrenal suppression. It could be used to screen for the side effects of steroids. In women, DHEA improves sexual satisfaction, fertility and age-related vaginal atrophy. Many factors are responsible for the inconsistent/negative results of some studies. Overreliance on animal models (DHEA is essentially a human molecule), different dosing protocols with non-pharmacological doses often unachievable in humans, rapid metabolism of DHEA, co-morbidities and organ-specific differences render data interpretation difficult. Nevertheless, a growing body of evidence supports the notion that DHEA is not just an overrated dietary supplement but a useful drug for some, but not all, human diseases. Large-scale randomised controlled trials are needed to fine-tune the indications and optimal dosing protocols before DHEA enters routine clinical practice.

Sex hormones in allergic conjunctivitis: altered levels of circulating androgens and estrogens in children and adolescents with vernal keratoconjunctivitis

Purpose. Vernal keratoconjunctivitis (VKC) is a chronic allergic disease mainly affecting boys in prepubertal age and usually recovering after puberty. To evaluate a possible role of sex hormones in VKC, serum levels of sex hormones in children and adolescents with VKC were assessed. Methods. 12 prepubertal and 7 early pubertal boys with active VKC and 6 male patients with VKC in remission phase at late pubertal age and 48 healthy age and sex-matched subjects were included. Serum concentration of estrone, 17 beta-estradiol, dehydroepiandrosterone-sulfate, total testosterone and free testosterone, dihydrotestosterone (DHT), cortisol, delta-4-androstenedione, follicle-stimulating hormone, luteinizing hormone, and sex-hormones binding globuline (SHBG) were evaluated. Results. Serum levels of Estrone were significantly increased in all groups of patients with VKC when compared to healthy controls (P < 0.001). Prepubertal and early pubertal VKC showed a significant decrease in DHT (P = 0.007 and P = 0.028, resp.) and SHBG (P = 0.01 and P = 0.002, resp.) when compared to controls and serum levels of SHBG were increased in late pubertal VKC in remission phase (P = 0.007). Conclusions and Relevance. VKC patients have different circulating sex hormone levels in different phases of the disease and when compared to nonallergic subjects. These findings suggest a role played by sex hormones in the pathogenesis and/or activity of VKC.

Androgens are bronchoactive drugs that act by relaxing airway smooth muscle and preventing bronchospasm

Changes in the androgen levels in asthmatic men may be associated with the severity of asthma. Androgens induce a nongenomic relaxation in airway smooth muscle, but the underlying mechanisms remain unclear. The aim of this study was to investigate the potential bronchorelaxing action of testosterone (TES) and its metabolites (5α- and 5β-dihydrotestosterone (DHT). A preventive effect on ovalbumin (OVA)-induced bronchospasm was observed in sensitized guinea pigs for each androgen. Androgens were studied in response to bronchoconstrictors: carbachol (CCh) and KCl in isolated trachea rings with and without epithelium from non-sensitized and sensitized animals as well as on OVA-induced contraction. Androgens concentration-dependently abolished the contraction in response to CCh, KCl, and OVA. There were significant differences in the sensitivity to the relaxation induced by each androgen. 5β-DHT was more potent for relaxing KCl-induced contraction, while TES and 5α-DHT were more potent for CCh- and OVA-induced contraction. No differences were found in preparations with and without epithelium or in the presence of a nitric oxide (NO) synthase inhibitor or an inhibitor of K(+) channels. These data indicate the absence of involvement of the epithelium-, NO- and K(+) channels-dependent pathway in androgen-induced relaxation. However, in dissociated tracheal myocytes loaded with the calcium-binding fluorescent dye Fura -2, physiological concentrations of androgens decreased the KCl-induced [Ca(2+)]i increment. 5β-DHT was the most potent at decreasing KCl-induced [Ca(2+)]i increment and preventing bronchospasm. We suggest that androgen-induced brochorelaxation was mediated via decreased Ca(2+) influx through L-type Ca(2+)channels but additional Ca(2+) entry blockade may be involved. Molecular changes in androgen structure may determine its preferential site of action.

Effects and mechanism of dehydroepiandrosterone on epithelial-mesenchymal transition in bronchial epithelial cells

BACKGROUND

Chronic persistent asthma is characterized by airway remodeling, in which epithelial-mesenchymal transition (EMT) may play a significant role. Dehydroepiandrosterone (DHEA), a steroid hormone and testosterone analog, is considered as an important immunomodulating hormone. However, its role in EMT remains unclear. We sought to investigate whether transforming growth factor-β1 (TGF-β1) stimulates human bronchial epithelial cells (16HBE-14o) to undergo EMT, and whether this transition can be abrogated by DHEA.

METHODS

The 16HBE-14o cells were stimulated with 5 ng/ml TGF-β1 for 3 days to induce EMT, with or without DHEA pretreatment, and assayed for epithelial or mesenchymal markers using Western Blot. The involvement of phosphoinositide 3-kinase (PI3K) -mediated signaling pathway was also evaluated, the epithelial cells were also incubated with pharmacological approaches (agonists and antagonists of Akt, LY294002 or IGF-1) or flutamide, the antagonist of androgen receptor. Results were analyzed using nonparametric statistical tests.

RESULTS

Our data demonstrate that treatment of 16HBE-14o cells with TGF-β1 for 3 days induced EMT as reflected by conversion to the spindle-like morphology, loss of E-cadherin, and acquisition of a-smooth muscle actin (a-SMA). Pretreatment of 16HBE-14o cells with DHEA preserved the epithelial-like morphology, restored the expression of E-cadherin, and abolished the activation of a-SMA, and this effect is a PI3K-dependent mechanism.

CONCLUSION

Our results indicate that TGF-β1 induces EMT in a PI3K-dependent manner in 16HBE-14o cells. DHEA inhibits the bronchial epithelial to mesenchymal transition via the inhibition of PI3K/Akt-dependent signal pathway stimulated by TGF-β1. Therefore, DHEA may be a useful therapy for asthma.

Induced pluripotent stem cells without c-Myc reduce airway responsiveness and allergic reaction in sensitized mice

BACKGROUND

Allergic disorders have increased substantially in recent years. Asthma is characterized by airway damage and remodeling. Reprogramming induced pluripotent stem cells (iPSCs) from adult somatic cells transfected by Oct-4/Sox-2/Klf-4, but not c-Myc, has shown the potential of embryonic-like cells. These cells have potential for multilineage differentiation and provide a resource for stem cell-based utility. However, the therapeutic potential of iPSCs without c-Myc (iPSC-w/o-c-Myc) in allergic diseases and airway hyperresponsiveness has not been investigated. The aim of this study was to evaluate the therapeutic effect of iPSC-w/o-c-Myc transplantation in a murine asthma model.

METHODS

BALB/c mice were sensitized with alum-adsorbed ovalbumin (OVA) and then challenged with aerosolized OVA. Phosphate-buffered saline or iPSC-w/o-c-Myc was then intravenously injected after inhalation. Serum allergen-specific antibody levels, airway hyperresponsiveness, cytokine levels in spleen cells and bronchoalveolar lavage fluid (BALF), and cellular distribution in BALF were then examined.

RESULTS

Treatment with iPSC-w/o-c-Myc effectively suppressed both Th1 and Th2 antibody responses, which was characterized by reduction in serum allergen-specific IgE, IgG, IgG1, and IgG2a levels as well as in interleukin-5 and interferon-γ levels in BALF and in OVA-incubated splenocytes. Meanwhile, regulatory cytokine, interleukin-10, was enhanced. Transplantation of iPSC-w/o-c-Myc also significantly attenuated cellular infiltration in BALF and allergic airway hyperresponsiveness. However, no tumor formation was observed 6 months after transplantation.

CONCLUSIONS

Administration of iPSC-w/o-c-Myc not only inhibited Th1 inflammatory responses but also had therapeutic effects on systemic allergic responses and airway hyperresponsiveness. iPSC-w/o-c-Myc transplantation may be a potential modality for treating allergic reactions and bronchial asthma.

Nongenomic bronchodilating action elicited by dehydroepiandrosterone (DHEA) in a guinea pig asthma model

Primates secrete large amounts of the precursor steroid dehydroepiandrosterone (DHEA); in humans, its levels are low during childhood and start declining after the fourth decade. It has been postulated that the progressive decline in DHEA levels may be related with the severity of asthma associated with age. To determine whether DHEA may regulate the airway smooth muscle (ASM) activity, isolated tracheal rings with and without epithelium from male guinea pigs were isometrically recorded to characterize the response of ASM to DHEA at different concentrations on KCl- and carbachol (CCh)-induced contraction as well as on ovalbumin (OVA)-induced contraction in sensitized guinea pigs. Additionally, we used barometric plethysmography in sensitized guinea pigs in order to compare changes of the lung resistance increased by the antigen challenge to OVA in the absence and presence of different doses of DHEA. DHEA concentration-dependently abolished the contraction to KCl, CCh and OVA, and no differences were found in preparations with and without epithelium. DHEA-induced relaxation was not modified by the suppression of protein synthesis or transcription, pharmacological inhibition of nitric oxide (NO) synthase, nor by antagonist of β2-adrenergic receptors or an inhibitor of the 3β-HSD enzyme. Likewise, Ca(2+)-induced contraction in Ca(2+)-free depolarized tissues was antagonized by DHEA, and the contraction to the L-type voltage-dependent calcium channel activator (Bay K 8644) was inhibited by DHEA. Furthermore, DHEA prevented OVA-induced increases in lung resistance. These results indicate that DHEA-induced relaxation in ASM is a nongenomic (membrane) action and is not produced after its bioconversion. The data suggest that DHEA-induced relaxation is an epithelium- and NO-independent mechanism that involves a blockade of voltage-dependent calcium channels and possible non-selective cation channels.

Do low testosterone levels contribute to the pathogenesis of asthma?

Asthma is a chronic inflammatory airway disorder that causes respiratory hypersensitivity and intermittent obstruction. Airway hyperresponsiveness to both specific and nonspecific stimuli is the hallmark of asthma. Although genetic susceptibility and airway inflammation are believed to play fundamental roles, etiology of asthma is unknown. In most cases, the treatment of asthma focuses on control of factors contributing to asthma severity and pharmacologic therapy including bronchodilator and anti-inflammatory agents. The prevalence of reported asthma is greater in prepubertal boys, with a change to a female predominance after puberty. Many epidemiological studies also suggest that women are at increased risk of developing adult-onset asthma and also suffer from more severe disease than men. This strongly suggests an important role for sex hormones in asthma. Previous articles provided us that, testosterone and/or its metabolites maintain the physiological balance of autoimmunity and protective immunity by preserving the number of regulatory cells. Testosterone is an immunosuppressant and is likely to be protective against immunological and inflammatory processes that trigger asthma. We hypothesized that the testosterone or selective androgen receptor modulators would have beneficial effects on asthma and could decrease the risk of asthmatic attacks.

Asthma and dehydroepiandrosterone (DHEA): facts and hypotheses

Dehydroepiandrosterone (DHEA) is considered as an important immunomodulating and anti-inflammatory hormone. Despite the continuing interest in DHEA replacement therapy, our knowledge of its effects upon asthma is very limited. DHEA is able to reverse cytokine imbalances associated with asthma, may prevent and attenuate allergic inflammation in airways, and does not possess the undesirable side effects of glucocorticoids; therefore, it may be potentially applied in the treatment of asthma. The steroid-sparing effect observed with DHEA clinically could appear especially favorable in asthmatic patients receiving oral treatment and those inhaling high doses of glucocorticoids. In addition, DHEA and its analogs might prove useful in reversing relative glucocorticoids insensitivity in patients with corticosteroid-resistant asthma. In this review we have focused specifically on DHEA's role in asthma.

Administration of dehydroepiandrosterone ameliorates experimental autoimmune neuritis in Lewis rats

Dehydroepiandrosterone (DHEA) is an abundant adrenal steroid in serum of humans, and has been reported to have anti-inflammatory, anti-proliferative, and certain immune-regulating properties. Experimental autoimmune neuritis (EAN) is a Th1 cell-mediated animal model of Guillain-Barré syndrome (GBS) in humans. In the present study, DHEA was administered subcutaneously to Lewis rats immunized with bovine peripheral myelin (BPM) in Freund's complete adjuvant. Rats treated with DHEA displayed significant delay in onset, decreased inflammatory cell infiltration in the PNS. Benefit was associated with significant decreases in numbers of IFN-gamma and TNF-alpha expressing cells in the PNS, BPM-stimulated T cell proliferation and IFN-gamma, TNF-alpha-secretion in the spleen cells. Only 2 mg DHEA-treated EAN rats decreased peak clinical score. No significant difference of supernatant IL-10 was found among the treatment and control groups. These results suggest that DHEA can ameliorate the severity of EAN by suppressing the proliferation of autoreactive T cell and expression of pro-inflammatory cytokines.

Effects of combined BCG and DHEA treatment in preventing the development of asthma

Both BCG and dehydroepiandrosterone (DHEA) induce Th1 immune responses and suppress Th2 allergic reactions. To investigate whether the combination of BCG and DHEA has an additive effect on asthma prevention, BALB/c mice (n = 10 per group) were given an intraperitoneal injection of BCG at the beginning of sensitization, and fed mice chow containing DHEA throughout the study. In female mice, the combined administration of 2 x 10(4) CFUs BCG and 0.01% DHEA effectively suppressed the ovalbumin-induced increase in airway sensitivity to methacholine (56.5 vs. 8.2 mg/mL, p < 0.01), while BCG (13.9 mg/mL) or DHEA (17.9 mg/mL) alone did not. However, the addition of high dose (0.1%) DHEA decreased the efficacy of high dose (2 x 10(5) CFUs) BCG in suppressing the airway responsiveness and eosinophilia. In male mice, the treatments with BCG and/or DHEA were less effective, and the interferon-gamma/interleukin-4 ratio in the splenocyte supernatant was significantly higher and the ovalbumin-specific IgE concentration in the serum was significantly lower as compared to female mice. In conclusion, the combination of low doses of BCG and DHEA had an additive effect in suppressing the development of airway hypersensitivity. Androgens in males and DHEA overdose might reduce the efficacy of BCG.

Effects of dehydroepiandrosterone on Th2 cytokine production in peripheral blood mononuclear cells from asthmatics

BACKGROUND/AIMS

The androgen dehydroepiandrosterone (DHEA) attenuates allergic inflammatory airway reactions by down-regulating the Th2 response in mice. The purpose of this study was to investigate whether DHEA suppresses Th2 cytokine production in cultured peripheral blood mononuclear cells (PBMCs) from asthmatic patients.

METHODS

Sixty-one consecutive suspected asthmatic or non-asthmatic men underwent tests for asthma. PBMCs from each subject were cultured with and without DHEA (0.01~10 microM) for 48 h. The concentrations of interferon (IFN)-gamma, interleukin (IL)-5, and IL-10 in the culture supernatant were measured via an enzyme-linked immunosorbent assay.

RESULTS

In PBMCs from subjects exhibiting methacholine airway hyperresponsiveness (AHR), DHEA significantly suppressed IL-10, IL-5, and IFN-gamma production in a dose-dependent manner (all p<0.001) and tended to increase the IFN-gamma/IL-5 ratio (p=0.087). DHEA (10 microM) suppressed cytokine production to a greater degree in subjects with AHR compared with those without AHR (IL-5: 24.0+/-7.8% vs. 40.9+/-3.6%, p<0.01; IFN-gamma: 29.7+/-7.0% vs. 54.5+/-5.1%, p<0.01). Cytokine suppression was significantly related to AHR, serum total IgE levels, and skin reactivity to house dust mites.

CONCLUSIONS

DHEA suppressed both Th1 and Th2 responses, with a Th1 bias, and the degree of suppression was associated with the severity of AHR or atopy. Therefore, DHEA may be a useful therapy for asthma.

Dehydroepiandrosterone and dehydroepiandrosterone sulphate in atopic allergy and chronic urticaria

The increasing amounts of evidence prove that sex hormones modulate different cells function, including mast cells and lymphocytes. Dehydroepiandrosterone (DHEA) and its sulphate ester (DHEA-S) are both the secretory products of adrenal glands and the most abundant hormones in the systemic circulation of humans, converted then into androgens and estrogens in the periphery. DHEA may affect production of Th1 and Th2- associated cytokines, suggesting their significance in diseases where imbalanced lymphocyte activity plays the essential role, also in atopic diseases. Reduced circulating concentration of these androgens has been demonstrated in patients with immune-inflammatory diseases, including atopic eczema/dermatitis syndrome and asthma. It is unknown however, whether such changes contribute in any way to etiopathogenesis of the disorders, or are merely their consequences. Chronic urticaria, not included in the atopic triad, is a mast cell-dependent disease characterised by activation of autoimmune and inflammatory processes responding to different factors. Alterations in the immune-neuro-endocrine milieu may contribute to the development of the disease. It has been demonstrated that DHEA-S concentration is significantly lower in the peripheral circulation of patients suffering from chronic urticaria, as compared with healthy subjects. On one hand, this reflects some changes in hormonal homeostasis in the course of urticarial processes, yet on the other, suggests some possible role for this hormone in pathophysiology of the disease. In this brief review we present the available data on DHEA-S involvement in events associated with atopic allergy as well as chronic urticaria.

Changes in serum sex hormone profiles after short-term low-dose administration of dehydroepiandrosterone (DHEA) to young and elderly persons

In man, serum concentrations of dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) decrease with age after the twenties. For this reason, the decline in DHEA and DHEAS concentrations may be related to the development of some chronic diseases that are prevalent in the older age population. In this study, we evaluate the benefit and safety level of DHEA administration to men as a hormone replacement therapy. Twenty-two healthy Japanese males (age 26-63; mean +/- SD, 41.0 +/- 10.0 yrs.) received 25 mg DHEA once a day orally in the morning for two weeks. Serum concentrations of steroid hormones and cytokines were measured before and after the DHEA administration. Glucose tolerance and insulin resistance were also assessed before and after the DHEA administration using a 75 g oral glucose tolerance test and homeostasis model assessment (HOMA-R), respectively. Serum DHEA and DHEAS levels were significantly elevated after the DHEA administration for all ages of test subjects. In subjects who were older than 41 yrs. (older group) serum androstenedione and estradiol levels were elevated after the DHEA administration. Significant negative correlations were observed between the serum DHEA concentration and the serum concentration of fasting insulin, HOMA-R, leptin, and high-sensitivity C-reactive protein for all subjects. Daily administration of 25 mg DHEA increased the serum DHEA, DHEAS, androstenedione, and estradiol levels of the subjects of the older group to the same level as that of younger subjects.

Maternal testosterone in pregnancy and atopic outcomes in childhood

BACKGROUND

In mice, androgens downregulate Th2 cytokine responses, but whether androgen levels during pregnancy might influence the development of allergy in the offspring has not been studied.

METHODS

In the Avon Longitudinal Study of Parents and Children (ALSPAC), a population-based birth cohort of 14 541 pregnancies, we related maternal blood total testosterone during pregnancy, measured in a subset of the cohort, to allergic outcomes in the offspring, including asthma, hayfever, eczema (n=543) and wheezing (n=532) at 69-81 months, and atopy (positive skin prick test to Dermatophagoides pteronyssinus, cat or grass, n=386) and blood total immunoglobulin E (IgE; n=314) at 7 years. We used logistic and linear regression to analyse binary outcomes and log-transformed IgE, respectively, controlling for potential confounders.

RESULTS

Maternal testosterone was negatively associated with total IgE in boys [adjusted geometric mean ratio (GMR), per doubling of testosterone, 0.33 (0.20-0.55), P=0.000038 (n=168)], but not in girls [GMR 1.04 (0.53-2.06), P=0.91 (n=146)], P-value interaction 0.0086. The effect in boys was even stronger in the absence of maternal atopic disease. Testosterone was not associated with skin test positivity or atopic disease in either sex.

CONCLUSIONS

Higher testosterone levels in pregnancy are associated with lower IgE production in boys.

A novel therapy for acute hepatitis utilizing dehydroepiandrosterone in the murine model of hepatitis

Dehydroepiandrosterone (DHEA), one of the major androgens secreted by the adrenal cortex, has been shown to have potential immunoreguratory properties. In this study, we examined the effect of DHEA in a mouse model of hepatitis. Mice were treated with DHEA and injected with concanavalin A (Con A) or lipopolysaccharide (LPS)/D-galactosamine (GalN). Cytokine expression was measured by quantitative RT-PCR and ELISA. Apoptosis was detected by the TUNEL method and by DNA fragmentation analysis. In the DHEA-treated mice, the serum levels of ALT and expression of inflammatory mediators were significantly decreased. The number of apoptotic cells was also much lower than that observed in control, untreated mouse liver tissue. There were fewer tumor necrosis factor-alpha (TNF-alpha)-induced apoptotic cells in H4IIE hepatoma cells treated with DHEA than in non-treated cells. DHEA decreased the expression levels of mRNA transcripts encoding TNF-alpha and iNOS. These results suggest that DHEA can reduce T-cell-mediated injury in the liver as manifest by inhibition of the expression of several inflammatory mediators and hepatocyte apoptosis. DHEA should, thus, be considered as a novel candidate for the therapy of liver injury.

Dampness in buildings as a risk factor for health effects, EUROEXPO: a multidisciplinary review of the literature (1998-2000) on dampness and mite exposure in buildings and health effects

The scientific literature on health effects from dampness in buildings, including mite exposure over the period 1998-2000 has been reviewed by an European group (EUROEXPO) of eight scientists in experience from medicine, epidemiology, toxicology and engineering. Forty studies deemed relevant have been the foundation for the conclusions. Dampness in buildings is a risk factor for health effects among atopics and non-atopics both in domestic and in public environments. However, the literature is not conclusive in respect of causative agents, e.g. mites, microbiological agents and organic chemicals from degraded building materials. There is a strong need for more multidisciplinary studies including expertise from all relevant areas. A general conclusion from the work was that there is a strong need for multidisciplinary reviews in scientific journals of articles dealing with associations between indoor environmental factors and health effects.

PRACTICAL IMPLICATIONS

There is good evidence for a true association between dampness in buildings and health. As the causative factors behind this association are not known, the main focus in practical investigations should be on finding out and remediate the reasons for the humidity problem.

Rosmarinic acid in perilla extract inhibits allergic inflammation induced by mite allergen, in a mouse model

BACKGROUND

Perilla and its constituent rosmarinic acid have been suggested to have anti-allergic activity. However, few studies have examined the effects on allergic asthma.

OBJECTIVE

The purpose of this study was to evaluate the effect of oral administration of perilla leaf extract, which contains high amount of rosmarinic acid, on a murine model of allergic asthma induced by house dust mite allergen.

METHODS

C3H/He mice were sensitized by intratracheal administration of Dermatophagoides farinae (Der f). Mice were orally treated with rosmarinic acid in perilla extract (PE) (1.5 mg/mouse/day).

RESULTS

Der f challenge of sensitized mice elicited pulmonary eosinophilic inflammation, accompanied by an increase in lung expression of IL-4 and IL-5, and eotaxin. Daily treatment with rosmarinic acid in PE significantly prevented the increases in the numbers of eosinophils in bronchoalveolar lavage fluids and also in those around murine airways. Rosmarinic acid in PE treatment also inhibited the enhanced protein expression of IL-4 and IL-5, and eotaxin in the lungs of sensitized mice. Der f challenge also enhanced allergen-specific IgG1, which were also inhibited by rosmarinic acid in PE.

CONCLUSION

These results suggest that oral administration of perilla-derived rosmarinic acid is an effective intervention for allergic asthma, possibly through the amelioration of increases in cytokines, chemokines, and allergen-specific antibody.

Neuroimmunoprotective effects of estrogen and derivatives in experimental autoimmune encephalomyelitis: Therapeutic implications for multiple sclerosis

The extensive literature and the work from our laboratory illustrate the large number of complex processes affected by estrogen that might contribute to the striking ability of 17beta-estradiol (E2) and its derivatives to inhibit clinical and histological signs of experimental autoimmune encephalomyelitis (EAE) in mice. These effects require sustained exposure to relatively low doses of exogenous hormone and offer better protection when initiated prior to induction of EAE. However, oral ethinyl estradiol (EE) and fluasterone, which lacks estrogenic side effects, could partially reverse clinical EAE when given after the onset of disease. The three main areas discussed in this review include E2-mediated inhibition of encephalitogenic T cells, inhibition of cell migration into central nervous system tissue, and neuroprotective effects that promote axon and myelin survival. E2 effects on EAE were mediated through Esr1 (alpha receptor for E2) but not Esr2 (beta receptor for E2), as were its antiinflammatory and neuroprotective effects. A novel finding is that E2 up-regulated the expression of Foxp3 and CTLA-4 that contribute to the activity of CD4+CD25+ Treg cells. The protective effects of E2 in EAE suggest its use as therapy for MS, although the risk of cardiovascular disease may complicate treatment in postmenopausal women. This risk could be minimized by using subpregnancy levels of exogenous E2 that produced synergistic effects when used in combination another immunoregulatory therapy. Alternatively, one might envision using EE or fluasterone metabolites alone or in combination therapies in both male and female MS patients.

Perimenstrual asthma: a syndrome without known cause or cure

Perimenstrual worsening of asthma has been documented in 30% to 40% of asthmatic women. This increase in symptoms has been backed up by increased health care use perimenstrually, as well as by cyclic variation in peak expiratory flows. The cause of perimenstrual asthma (PMA) remains unclear. Fluctuations in hormone levels, their ratios, or both are a plausible explanation but have not been demonstrated with any consistency. Influences of sex hormones on inflammation is an area of future research, as are hormone-induced changes in smooth muscle function and beta-adrenergic receptors, prostaglandin levels, and fluid retention in the bronchial mucosa. In the light of the high prevalence of PMA, it is difficult to understand why there has been no randomized controlled trial of hormone therapy. Nevertheless, several case reports have suggested beneficial effects of estrogens, progestins, and their combination. In light of these positive case reports, well-designed, double-blind studies of sufficient sample size should now be performed to give treatment of PMA an evidence base.

A synthetic androstene derivative and a natural androstene metabolite inhibit relapsing-remitting EAE

Experimental allergic encephalomyelitis (EAE), a Th1 polarized demyelinating disease of the central nervous system (CNS), shares many pathological and clinical similarities with multiple sclerosis (MS), and thus represents an attractive animal model for this disease. The goal of this study was to evaluate the suppressive effects of fluasterone (HE2500), a synthetic androstene derivative, and androstenetriol (HE2200), a natural androstene hormone on EAE. SJL mice were immunized with proteolipid protein (PLP) 139-151 peptide/CFA to induce EAE. Starting on day -7, animals were given daily injections (s.c.) of derivatives (3.0 mg) in vehicle, or vehicle alone for 33 days. Both HE2500 and HE2200 significantly delayed the onset, reduced the peak clinical score and cumulative disease index of EAE, and prevented or significantly attenuated relapses. Lower doses or other routes of administration were less effective. Moreover, T cells from treated mice had significantly reduced PLP 139-151-specific T cell proliferation responses and reduced numbers of TNF-alpha- and IFN-gamma-producing cells in the CNS. Daily treatment of B10.PL mice with HE2500, starting on day 0, completely prevented the development of disease in these animals. Finally, SJL mice treated with HE2500 at EAE onset showed significantly reduced mean clinical scores. Thus, these compounds, which have been reported to have a few androgenic or estrogenic side effects, appear to have a potent inhibitory activity in EAE. These observations suggest that HE2500 and/or HE2200 limit the production of autoimmune Th1 associated cytokines, and ultimately may be beneficial for patients with MS or other autoimmune diseases.

Effects of xiao-qing-long-tang (XQLT) on bronchoconstriction and airway eosinophil infiltration in ovalbumin-sensitized guinea pigs: in vivo and in vitro studies

BACKGROUND

Xiao-qing-long-tang (XQLT sho-seiru-to), a traditional Chinese medicine, has been used to treat patients with bronchial asthma in Oriental countries for several centuries. However, the therapeutic mechanisms of this Chinese medicine remain a matter of considerable debate. Therefore, a series of experiments using ovalbumin-sensitized guinea pigs was performed to elucidate the possible antiasthmatic effect of XQLT.

METHODS

The effect of XQLT on ovalbumin-induced airway inflammation in a guinea pig model of allergic asthma was examined, and early and late asthmatic responses were measured in terms of airway resistance and extent of eosinophil infiltration. Furthermore, the bronchorelaxing effect of XQLT was measured in isolated guinea pig trachea.

RESULTS

XQLT significantly inhibited the antigen-induced immediate asthmatic response (IAR) and late asthmatic response (LAR) in actively sensitized guinea pigs. Cumulative administration of XQLT caused concentration-dependent relaxation of the carbachol-precontracted guinea pig trachea. The bronchorelaxing effect of XQLT was reversed by ICI-118551, a selective beta2-adrenoceptor antagonist. Furthermore, examination of bronchoalveolar lavage fluid (BALF) revealed that XQLT significantly suppressed the increase in eosinophils (24 h after antigen challenge) in the airway. In addition, XQLT significantly attenuated the increase in eosinophils at 1, 6, 24, 48, and 72 h after antigen challenge when it was administered once daily from the day of sensitization to the day of challenge. Histopathologic examination results showed that XQLT suppressed eosinophil infiltration into lung tissue.

CONCLUSIONS

These results demonstrate that the antiasthmatic effects of XQLT appear to be partly mediated by stimulation of beta2-adrenoceptors, leading to bronchorelaxation, and that XQLT inhibits the infiltration of eosinophils into the airway. Thus, XQLT may be useful for the prevention or treatment of asthma.