Obesity promotes prolonged ovalbumin-induced airway inflammation modulating T helper type 1 (Th1), Th2 and Th17 immune responses in BALB/c mice.

Clinical and epidemiological studies indicate that obesity affects the development and phenotype of asthma by inducing inflammatory mechanisms in addition to eosinophilic inflammation. The aim of this study was to assess the effect of obesity on allergic airway inflammation and T helper type 2 (Th2) immune responses using an experimental model of asthma in BALB/c mice. Mice fed a high-fat diet (HFD) for 10 weeks were sensitized and challenged with ovalbumin (OVA), and analyses were performed at 24 and 48 h after the last OVA challenge. Obesity induced an increase of inducible nitric oxide synthase (iNOS)-expressing macrophages and neutrophils which peaked at 48 h after the last OVA challenge, and was associated with higher levels of interleukin (IL)-4, IL-9, IL-17A, leptin and interferon (IFN)-γ in the lungs. Higher goblet cell hyperplasia was associated with elevated mast cell influx into the lungs and trachea in the obese allergic mice. In contrast, early eosinophil influx and lower levels of IL-25, thymic stromal lymphopoietin (TSLP), CCL11 and OVA-specific immunoglobulin (IgE) were observed in the obese allergic mice in comparison to non-obese allergic mice. Moreover, obese mice showed higher numbers of mast cells regardless of OVA challenge. These results indicate that obesity affects allergic airway inflammation through mechanisms involving mast cell influx and the release of TSLP and IL-25, which favoured a delayed immune response with an exacerbated Th1, Th2 and Th17 profile. In this scenario, an intense mixed inflammatory granulocyte influx, classically activated macrophage accumulation and intense mucus production may contribute to a refractory therapeutic response and exacerbate asthma severity.

Elevated IL-33 expression is associated with pediatric eosinophilic esophagitis, and exogenous IL-33 promotes eosinophilic esophagitis development in mice.

We tested whether the T helper (Th) type 2 (Th2) cell agonist and allergenic ligand IL-33 was associated with eosinophilic esophagitis (EoE) development in a pediatric cohort and whether IL-33 protein could induce disease symptoms in mice. Biopsies from EoE patients or controls were used to measure IL-33 mRNA and protein expression. Increased expression of IL-33 mRNA was found in the esophageal mucosa in EoE. IL-33 protein was detected in cells negative for CD45, mast cells, and epithelial cell markers near blood vessels. Circulating levels of IL-33 were not increased. The time course for IL-33 gene expression was quantified in an established Aspergillus fumigatus allergen mouse model of EoE. Because IL-33 induction was transient in this model and chronicity of IL-33 expression has been demonstrated in humans, naive mice were treated with recombinant IL-33 for 1 wk and esophageal pathology was evaluated. IL-33 application produced changes consistent with phenotypically early EoE, including transmural eosinophilia, mucosal hyperproliferation, and upregulation of eosinophilic genes and chemokines. Th2 cytokines, including IL-13, along with innate lymphoid cell group 2, Th1/17, and M2 macrophage marker genes, were increased after IL-33 application. IL-33-induced eosinophilia was ablated in IL-13 null mice. In addition, IL-33 induced a profound inhibition of the regulatory T cell gene signature. We conclude that IL-33 gene expression is associated with pediatric EoE development and that application of recombinant protein in mice phenocopies the early clinical phase of the human disease in an IL-13-dependent manner. IL-33 inhibition of esophageal regulatory T cell function may induce loss of antigenic tolerance, thereby providing a mechanistic rationale for EoE development.

The fraction of exhaled nitric oxide improves prediction of clinical allergic reaction to peanut challenge in children.

BACKGROUND: Retrospective studies of childhood peanut allergy demonstrate serum-specific IgE (IgE) levels against the peanut allergen Ara h2 may help predict a clinical reaction at food challenge. Fraction of exhaled nitric oxide (FeNO) is a non-invasive tool correlating to allergic airways inflammation and has been independently associated with increased food-specific IgE. OBJECTIVE: To assess the validity of serum-specific Ara h2 IgE measured prospectively to diagnose peanut allergy and explore the utility of FeNO as a non-invasive screening tool for childhood food challenge. METHODS: We recruited 53 participants from a cohort of consecutive children scheduled for an open-labelled peanut food challenge (OFC) by their paediatric allergist. Participants underwent skin prick test (SPT) measurement for sensitization to whole peanut extract, and serum was collected for Ara h2-specific IgE. FeNO was also measured in all cooperative children before the challenge. OFC and assessment of reaction were undertaken by clinicians blinded to test results. RESULTS: Ara h2-specific IgE and FeNO each showed improved diagnostic accuracy when compared to SPT. Receiver operator characteristic curve analysis gave an area under the curve (AUC) for Ara h2 sIgE of 0.84 (95% CI, 0.72-0.96). The AUC for FeNO, 0.83 (95% CI, 0.71-0.95), was equivalent to that of Ara h2. Combined AUC for SPT, sIgE to Ara h2 and FeNO was 0.96 (95% CI 0.90-1.00). There was no correlation between FeNO and serum nitrite levels (rs = -0.13, P = 0.6, n = 18). CONCLUSION AND CLINICAL RELEVANCE: Prospectively measured Ara h2-specific IgE improves diagnostic accuracy and reduces unsuccessful challenge to peanut. FeNO levels may provide improved diagnostic accuracy in a paediatric population undergoing OFC. The proposed FeNO-based diagnostic algorithm requires further validation studies.

Targeting translational control as a novel way to treat inflammatory disease: the emerging role of microRNAs.

Chronic inflammatory diseases (e.g. asthma and chronic obstructive pulmonary disease)are leading causes of morbidity and mortality world-wide and effective treatments are limited. These disorders can often be attributed to abnormal immune responses to environmental stimuli and infections. Mechanisms leading to inflammation are complex,resulting from interactions of structural cells and activation of both the adaptive and innate arms of the immune system. The activation of structural and immune cells involves both temporary and permanent changes in gene expression in these cells, which underpin chronic inflammation and tissue dysfunction. miRNAs are small non-coding RNAs increasingly being recognized to play important roles in the post-transcriptional regulation of gene expression in mammalian cells by regulating translation. Individual miRNA scan exert their effects by directly inhibiting the translation or stability of multiple mRNAs simultaneously. Thus, the expression or blockade of function of a single miRNA (miR) can result in pronounced alterations in protein expression within a given cell. Dysregulation of miRNA expression may subsequently alter cellular function, and in certain situations predispose to disease. Our current understanding of the role of miRNA in the regulation of inflammatory disease (e.g. allergic diseases) remains limited. In this review, we provide an overview of the current understanding of miRNA biogenesis and function, the roles miRNA play in the regulation of immune cell function and their potential contribution to inflammatory diseases. We also highlight strategies to alter miRNA function for experimental or therapeutic gain, and discuss the potential utility and limitations of targeting these molecules as anti-inflammatory strategies.

Environmental bacteria and childhood asthma.

BACKGROUND: We have previously found an inverse association of bacterial diversity with childhood asthma. It remains unclear whether certain bacteria account for the protective effect. METHODS: The high variability of the bacterial 16S rRNA gene allows assessing diversity and specificity of bacterial communities by single-strand configuration polymorphism (SSCP). DNA was extracted from mattress dust samples of 489 school-age children from rural and suburban regions in Germany. A fragment of the bacteria-specific 16S rRNA gene was amplified by PCR, digested to single-strand DNA, and subjected to electrophoresis. The resulting band patterns reflect the underlying DNA sequences. The individual bands were tested for associations with asthma, hay fever, and atopy in quantitative and qualitative multivariable analyses. Significantly associated bands were isolated and sequenced. The sequences were compared to a database, and distinct bacteria were identified. RESULTS: Seven of 76 independent bands were found to be inversely associated with asthma, atopic sensitization, and hay fever with odds ratios ranging from 0.17 to 0.73. The bands contained the sequences of Acinetobacter sp., Lactobacillus spp., Neisseria spp., Staphylococcus sciuri, Jeotgalicoccus sp., Corynebacterium spp., and others. CONCLUSIONS: In a diverse microbial environment, certain bacteria may account for the protective effect on the development of asthma and atopy.

Vitamin D status in pregnant women with asthma and its association with adverse respiratory outcomes during infancy.

BACKGROUND: Vitamin D may influence pregnancy and infant outcomes, especially infant respiratory health. This study aimed to examine vitamin D status in pregnant women with asthma, and whether higher vitamin D levels are associated with fewer adverse respiratory outcomes in their infants. METHODS: Pregnant women with asthma, recruited from John Hunter Hospital Newcastle Australia (latitude 33°S), had serum total 25-hydroxyvitamin-D (25(OH)D) measured at 16 and 35 weeks gestation. Infant respiratory outcomes were collected at 12 months by parent-report questionnaire. Mother-infant dyads were grouped by serum 25(OH)D during pregnancy: 25(OH)D < 75 nmol/L (at both time-points) versus 25(OH)D ≥ 75 nmol/L (at one or both time-points). RESULTS: In 52 pregnant women with asthma, mean serum 25(OH)D levels were 61 (range 26-110) nmol/L at 16 weeks, and 65 (range 32-116) nmol/L at 35 weeks, gestation. Thirty-one (60%) women had 25(OH)D < 75 nmol/L at both time-points; 21 (40%) had 25(OH)D ≥ 75 nmol/L at one or both time-points. Maternal 25(OH)D < 75 nmol/L during pregnancy was associated with a higher proportion of infants with "wheeze ever" at 12 months, compared with 25(OH)D ≥ 75 nmol/L (71 versus 43%, p = .04). Infant acute-care presentations (45 versus 13%, p = .02) and oral corticosteroid use (26 versus 4%, p = .03) due to "asthma/wheezing" were higher in the maternal group with 25(OH)D < 75 nmol/L, versus ≥75 nmol/L. CONCLUSIONS: Most pregnant women with asthma had low vitamin D status, which persisted across gestation. Low maternal vitamin D status was associated with greater risk of adverse respiratory outcomes in their infants, a group at high risk of developing childhood asthma.

A pathogenic role for tumor necrosis factor-related apoptosis-inducing ligand in chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a life-threatening inflammatory respiratory disorder, often induced by cigarette smoke (CS) exposure. The development of effective therapies is impaired by a lack of understanding of the underlining mechanisms. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a cytokine with inflammatory and apoptotic properties. We interrogated a mouse model of CS-induced experimental COPD and human tissues to identify a novel role for TRAIL in COPD pathogenesis. CS exposure of wild-type mice increased TRAIL and its receptor messenger RNA (mRNA) expression and protein levels, as well as the number of TRAIL(+)CD11b(+) monocytes in the lung. TRAIL and its receptor mRNA were also increased in human COPD. CS-exposed TRAIL-deficient mice had decreased pulmonary inflammation, pro-inflammatory mediators, emphysema-like alveolar enlargement, and improved lung function. TRAIL-deficient mice also developed spontaneous small airway changes with increased epithelial cell thickness and collagen deposition, independent of CS exposure. Importantly, therapeutic neutralization of TRAIL, after the establishment of early-stage experimental COPD, reduced pulmonary inflammation, emphysema-like alveolar enlargement, and small airway changes. These data provide further evidence for TRAIL being a pivotal inflammatory factor in respiratory diseases, and the first preclinical evidence to suggest that therapeutic agents that target TRAIL may be effective in COPD therapy.

Growth of hyperactive children on maintenance regimen of methylphenidate.

The growth in height and weight of 86 hyperactive children receiving methylphenidate hydrochloride (average, 40 mg/day for up to four years) was compared with general population norms on recently updated growth charts. A significant decrease in height percentile was apparent after 2, 3, and 4 years of treatment but not after one year. A significant loss in weight percentile occurred onward from the first year of treatment. Dosage was significantly associated with the decrease in height and weight percentile. Greater initial height and weight were associated with greater growth decrements. The use of adjunctive thioridazine hydrochloride (mean, 87 mg/day) did not influence the growth of children receiving methylphenidate. Although the magnitude of the growth suppressant effect in groups was small (dosage accounted for only 2% of the variance in final height), the results suggest that clinicians should monitor the growth of hyperactive children receiving stimulants and consider dosage reduction in individual cases should evidence of growth suppression occur.

Effects of artificial food colorings in children with hyperactive symptoms. A critical review and results of a controlled study.

The "Feingold diet," which eliminates artificial food colorings, has been claimed to be beneficial to hyperactive children. Previous studies have yielded equivocal results. We sought to maximize the likelihood of demonstrating behavioral effects of artificial food colorings by (1) studying only children who were already on the Feingold diet and who were reported by their parents to respond markedly to artificial food colorings, (2) attempting to exclude placebo responders, and (3) administering high dosages of coloring. The design was a double-blind crossover with randomized; 11 children maintained on the Feingold diet were challenged with food coloring and placebo (one each week). Evaluations by parents, teachers, and psychiatrists and psychological testing yielded no evidence of a food coloring effect.

Methylphenidate effects on symptoms of attention deficit disorder in adults.

The objectives of this study were (1) to determine whether attention deficit disorder (ADD) is a specific diagnostic entity in adulthood; (2) to evaluate, using a double-blind crossover design, the efficacy of methylphenidate hydrochloride in adults with evidence of residual ADD with hyperactivity (ADD-H) (N = 26); and (3) to evaluate the specificity of drug response by also administering methylphenidate to patients with similar adult symptoms but no childhood history of ADD-H (N = 35). Results indicated success in differentiating relatively distinct groups. However, no overall benefit from methylphenidate was evident, regardless of childhood history of ADD-H. Approximately 25% of the sample appeared clinically to benefit from methylphenidate, but no clear-cut predictors of drug response were identified; history of drug abuse (polydrug) appeared to be the best predictor. Even among the responders, benefit was generally not as marked nor as clinically valuable as in childhood ADD-H.

Methylphenidate and growth in hyperactive children. A controlled withdrawal study.

The effect of stimulants on growth has been controversial. Among hyperactive children receiving long-term methylphenidate hydrochloride treatment, we examined the effects of methylphenidate withdrawal on the growth of hyperactive children randomly assigned to be taken off, or remain on, the medication regimen over two consecutive summers. After one summer, no group difference in height was found, but weight was higher in the group that had been taken off methylphenidate therapy. In contrast, two summers of being off methylphenidate treatment had a significant positive effect on height but not on weight. The results document a linkage between exposure to methylphenidate and reduction in growth velocity. However, they do not address whether the medication has long-term effects on height.

Extended-release physostigmine in Alzheimer disease: a multicenter, double-blind, 12-week study with dose enrichment. Physostigmine Study Group.

BACKGROUND: The efficacy of extended-release physostigmine salicylate, an acetylcholinesterase inhibitor, was evaluated in 850 subjects with mild-to-moderate Alzheimer disease (AD) in a multicenter trial. METHODS: Subjects initially entered a dose-enrichment phase in which they received 1 week each of physostigmine salicylate, 24 mg/d and 30 mg/d, and daily placebo. Among the subjects who completed this phase, 35.9% responded to physostigmine treatment, whereas 62.4% were considered nonresponders, and 1.6% could not be evaluated because of missing data. After a 4-week placebo-washout phase, 176 responder subjects were randomized to receive their best dose of physostigmine or placebo in a 12-week double-blind phase. Primary efficacy measures included the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog), the Clinician's Interview-Based Impression of Change With Caregiver Input (CIBIC+), and the Clinical Global Impression of Change (CGIC). RESULTS: In the intent-to-treat analysis of the double-blind phase, physostigmine-treated subjects scored -2.02 points better than placebo-treated subjects on the ADAS-Cog (F1,167 = 6.42 [P = .01]) and 0.33 points higher on the CIBIC+ (F1,150 = 5.68 [P = .02]). No significant improvement was observed on the CGIC or the secondary outcome measures. Nausea and vomiting were experienced by 47.0% of all physostigmine-treated subjects during the double-blind phase. CONCLUSIONS: Physostigmine demonstrated a statistically significant benefit compared with placebo on a clinical global rating of change and an objective test of cognitive function. Given the frequency of gastrointestinal side effects, the role of this agent in clinical use remains to be determined.

Ceruletide for schizophrenia: a double-blind study.

Ceruletide, an analog of cholecystokinin (CCK), has been reported to have neuroleptic-like activity in mice, and, in three open studies, to benefit schizophrenic patients. This study evaluated ceruletide in schizophrenia using a double-blind design. Subjects were 17 chronic schizophrenics with residual symptoms following stabilization with neuroleptics. Patients randomly received two injections, 1 week apart, of either ceruletide (0.6 microgram/kg im) or placebo, while continuing neuroleptics; this regimen was found helpful in earlier studies. Evaluation included ratings of 29 variables related to prognosis in schizophrenia (e.g., age, number of previous hospitalizations), regular BPRSs and SCL-90s, and psychiatrist, patient, and relative ratings of global improvement. Results showed few significant differences between ceruletide and placebo, with exceptions as likely to favor placebo as ceruletide. Among the patients on ceruletide, no predictors of benefit were found. Possible reasons for the negative results are discussed.

A placebo-controlled evaluation of vasopressin for ECT-induced memory impairment.

Vasopressin may be involved in normal memory functions and may alleviate certain memory impairments. In this study, the usefulness of vasopressin to relieve electroconvulsive therapy (ECT)-induced memory impairment was evaluated using a placebo-controlled, random assignment, double-blind design. Patients were 33 depressives receiving bilateral ECT. Vasopressin, in a nasal spray, was administered q.i.d. from the first through the fifth ECT. Extensive memory testing evaluated both retrograde and anterograde amnesia; ratings of depression and patient ratings of subjective memory complaints were also obtained. Results did not show statistically significant evidence of benefit from vasopressin, though a number of comparisons were in the predicted direction. The role of vasopressin in reducing memory impairment of various types remains to be elucidated.

Metoprolol for intermittent explosive disorder.

Metoprolol, a selective beta 1-adrenoreceptor blocker, was administered to two patients with intermittent explosive disorder who had not done well with previous medications, including propranolol and carbamazepine. Both patients improved dramatically, suggesting clinical and theoretical relevance.

A high-dose, double-blind study of ceruletide in the treatment of schizophrenia.

Ceruletide, a cholecystokinin analogue, has been reported to interact with dopamine in the CNS and to benefit schizophrenic individuals. The authors, using a double-blind design, a higher total dose, and a larger sample size than previous studies, found no evidence of benefit.

State-dependent learning in hyperactive children receiving methylphenidate.

State-dependent learning refers to a failure of learning mastered under one drug condition to be remembered when tested under another drug condition. Previous studies of state-dependent learning in hyperactive children receiving stimulants have yielded conflicting results. The authors systematically evaluated learning and transfer of learning in children who were or were not receiving methylphenidate and included several design features intended to optimize the likelihood of demonstrating state-dependent learning. They found no evidence of state-dependent learning. These results diminish concern regarding state-dependent effects in hyperactive children who are positive drug responders and who are clinically administered methylphenidate to control their hyperactivity.

New potent antihyperglycemic agents in db/db mice: synthesis and structure-activity relationship studies of (4-substituted benzyl) (trifluoromethyl)pyrazoles and -pyrazolones.

The synthesis, structure-activity relationship (SAR) studies, and antidiabetic characterization of 1,2-dihydro-4-[[4-(methylthio)phenyl]methyl]-5-(trifluoromethyl)-3H- pyrazol-3-one (as the hydroxy tautomer; WAY-123783, 4) are described. Substitution of 4-methylthio, methylsulfinyl, or ethyl to a benzyl group at C4, in combination with trifluoromethyl at C5 of pyrazol-3-one, generated potent antihyperglycemic agents in obese, diabetic db/db mice (16-30% reduction in plasma glucose at 2 mg/kg). The antihyperglycemic effect was associated with a robust glucosuria (> 8 g/dL) observed in nondiabetic mice. Chemical trapping of four of the seven possible tautomeric forms of the heterocycle by mono- and dialkylation at the acidic hydrogens provided several additional potent analogs (39-43% reduction at 5 mg/kg) of the lead 4 as well as a dialkylated pair of regioisomers that showed separation of the associated glucosuric effect produced by all of the active analogs in normal mice. Further pharmacological characterization of the lead WAY-123783 (ED50 = 9.85 mg/kg, po in db/db mice), in oral and subcutaneous glucose tolerance tests, indicated that unlike the renal and intestinal glucose absorption inhibitor phlorizin, pyrazolone 4 does not effectively block intestinal glucose absorption. SAR and additional pharmacological data reported herein suggest that WAY-123783 represents a new class of potent antihyperglycemic agents which correct hyperglycemia by selective inhibition of renal tubular glucose reabsorption.

Tumor cell spheroids as a model for evaluation of metabolic changes after irradiation.

UNLABELLED: Tumor cell spheroids provide a good model to evaluate the relationship between tumor volume and the number of viable cells in the volume with the uptake of metabolic tracers before and after therapy. They represent the only in vitro model that allows the determination of the activity per unit volume, a parameter which is relevant for interpretation of PET studies. The purpose of this study was to evaluate this model with respect to the uptake of 14C-FDG, 3H-methionine and 3H-thymidine with and without exposure to irradiation. METHODS: Spheroids of the human adenocarcinoma cell line SW 707 were incubated in media containing 14C-FDG, 3H-methionine or 3H-thymidine for 1 hr at 1, 4, 8, 24 and 48 hr after exposure to a single radiation dose of 6 Gy together with control spheroids. Tracer uptake after incubation was expressed in cpm/ spheroid, cpm/1000 viable cells and cpm/0.01 mm3. In addition, the proliferative capacity of control and irradiated spheroids was determined using the clonogenic assay. RESULTS: Spheroid uptake of FDG decreased with time after irradiation, while the uptake per 1000 viable cells was increased significantly. The activity per unit volume remained unchanged in comparison to control spheroids. Methionine uptake per spheroid was unchanged after irradiation because of the high increase in uptake per 1000 viable cells. Uptake per unit volume also remained unchanged in comparison to controls. Thymidine uptake per 1000 viable cells did not change after irradiation but showed significant differences in uptake per spheroid and per unit volume compared to controls. The percentage of thymidine incorporated into the TCA-precipitable fraction containing DNA was 50% in controls and decreased to 12% at 24 hr after irradiation. The suppressed clonogenic capacity early after therapy recovered with the increase in thymidine uptake and with the increase in thymidine incorporation into DNA. CONCLUSION: The results show that the activity determined within a certain tumor volume is a balance between the increased tracer uptake by surviving cells after therapy and the lack of tracer uptake by dead cells, which still contribute to the tumor volume. Thus, the resulting unchanged activity per unit volume within the spheroid, as found for FDG and methionine, may not fully reflect therapy-induced metabolic changes in tumors.

Methylphenidate in mild depression: a double-blind controlled trial.

The literature on the use of stimulants in depression is reviewed, and a controlled study is described. Twenty mildly depressed outpatients with Hamilton Depression Rating Scale scores of 14-24 were entered into a double-blind crossover study with randomized order, comparing methylphenidate (up to 60 mg/day) and placebo. No antidepressant effect was found. A beneficial effect of stimulants in subgroups of depressed patients remains to be proven.