Early intervention with suplatast tosilate for prophylaxis of pediatric atopic asthma: a pilot study

Sialic acid and food allergies: The link between nutrition and immunology

Food allergies (FA), a major public health problem recognized by the World Health Organization, affect an estimated 3%-10% of adults and 8% of children worldwide. However, effective treatments for FA are still lacking. Recent advances in glycoimmunology have demonstrated the great potential of sialic acids (SAs) in the treatment of FA. SAs are a group of nine-carbon α-ketoacids usually linked to glycoproteins and glycolipids as terminal glycans. They play an essential role in modulating immune responses and may be an effective target for FA intervention. As exogenous food components, sialylated polysaccharides have anti-FA effects. In contrast, as endogenous components, SAs on immunoglobulin E and immune cell surfaces contribute to the pathogenesis of FA. Given the lack of comprehensive information on the effects of SAs on FA, we reviewed the roles of endogenous and exogenous SAs in the pathogenesis and treatment of FA. In addition, we considered the structure-function relationship of SAs to provide a theoretical basis for the development of SA-based FA treatments.

Pediatric Allergic Diseases, Food Allergy, and Oral Tolerance

Pediatric allergic disease is a significant health concern worldwide, and the prevalence of childhood eczema, asthma, allergic rhinitis, and food allergy continues to increase. Evidence to support specific interventions for the prevention of eczema, asthma, and allergic rhinitis is limited, and no consensus on prevention strategies has been reached. Randomized controlled trials investigating the prevention of food allergy via oral tolerance induction and the early introduction of allergenic foods have been successful in reducing peanut and egg allergy prevalence. Infant weaning guidelines in the United Sates were recently amended to actively encourage the introduction of peanut for prevention of peanut allergy.

A systematic review of predictive models for asthma development in children

BACKGROUND

Asthma is the most common pediatric chronic disease affecting 9.6 % of American children. Delay in asthma diagnosis is prevalent, resulting in suboptimal asthma management. To help avoid delay in asthma diagnosis and advance asthma prevention research, researchers have proposed various models to predict asthma development in children. This paper reviews these models.

METHODS

A systematic review was conducted through searching in PubMed, EMBASE, CINAHL, Scopus, the Cochrane Library, the ACM Digital Library, IEEE Xplore, and OpenGrey up to June 3, 2015. The literature on predictive models for asthma development in children was retrieved, with search results limited to human subjects and children (birth to 18 years). Two independent reviewers screened the literature, performed data extraction, and assessed article quality.

RESULTS

The literature search returned 13,101 references in total. After manual review, 32 of these references were determined to be relevant and are discussed in the paper. We identify several limitations of existing predictive models for asthma development in children, and provide preliminary thoughts on how to address these limitations.

CONCLUSIONS

Existing predictive models for asthma development in children have inadequate accuracy. Efforts to improve these models' performance are needed, but are limited by a lack of a gold standard for asthma development in children.

Risk factors for asthma: is prevention possible?

Asthma is one of the most common diseases in the world, resulting in a substantial burden of disease. Although rates of deaths due to asthma worldwide have reduced greatly over the past 25 years, no available therapeutic regimens can cure asthma, and the burden of asthma will continue to be driven by increasing prevalence. The reasons for the increase in asthma prevalence have not been defined, which limits the opportunities to develop targeted primary prevention measures. Although associations are reported between a wide range of risk factors and childhood asthma, substantiation of causality is inherently difficult from observational studies, and few risk factors have been assessed in primary prevention studies. Furthermore, none of the primary prevention intervention strategies that have undergone scrutiny in randomised controlled trials has provided sufficient evidence to lead to widespread implementation in clinical practice. A better understanding of the factors that cause asthma is urgently needed, and this knowledge could be used to develop public health and pharmacological primary prevention measures that are effective in reducing the prevalence of asthma worldwide. To achieve this it will be necessary to think outside the box, not only in terms of risk factors for the causation of asthma, but also the types of novel primary prevention strategies that are developed, and the research methods used to provide the evidence base for their implementation. In the interim, public health efforts should remain focused on measures with the potential to improve lung and general health, such as: reducing tobacco smoking and environmental tobacco smoke exposure; reducing indoor and outdoor air pollution and occupational exposures; reducing childhood obesity and encouraging a diet high in vegetables and fruit; improving feto-maternal health; encouraging breastfeeding; promoting childhood vaccinations; and reducing social inequalities.

Novel treatments of asthma and allergic diseases

The prevalence of allergic diseases has considerably increased, mostly in industrialized countries (> 20%), and asthma affects approximately 300 million individuals worldwide. Current therapies are able to control symptoms although they do not modulate immunological dysregulation that characterizes allergic diseases. Over the last 30 years, only a few new drugs have been introduced on the market and they all act on Th2-type response which has a critical role in the pathogenesis of allergic diseases. Recently, a new scenario has been opened on Th17-cells, Th1-type cytokines and innate immune system components involved in the inflammatory pathogenesis of asthma and other allergic diseases. These findings suggest a promising therapeutic role of new agents that block the action of specific cytokines. Furthermore, the concept of an intrinsic structural defect in the bronchial epithelium paves the way to innovative therapeutic strategies. In this review we present an update on therapies for allergic diseases with special focus on asthma.

Effect of Kuwanon G isolated from the root bark of Morus alba on ovalbumin-induced allergic response in a mouse model of asthma

The root bark of Morus alba L. (Mori Cortex Radicis; MCR) is traditionally used in Korean medicine for upper respiratory diseases. In this study, we investigated the antiasthmatic effect of kuwanon G isolated from MCR on ovalbumin (OVA)-induced allergic asthma in mice. Kuwanon G (1 and 10 mg/kg) was administered orally in mice once a day for 7 days during OVA airway challenge. We measured the levels of OVA-specific IgE and Th2 cytokines (IL-4, IL-5, and IL-13) in the sera or bronchoalveolar lavage (BAL) fluids and also counted the immune cells in BAL fluids. Histopathological changes in the lung tissues were analyzed. Kuwanon G significantly decreased the levels of OVA-specific IgE and IL-4, IL-5, and IL-13 in the sera and BAL fluids of asthma mice. Kuwanon G reduced the numbers of inflammatory cells in the BAL fluids of asthma mice. Furthermore, the pathological feature of lungs including infiltration of inflammatory cells, thickened epithelium of bronchioles, mucus, and collagen accumulation was inhibited by kuwanon G. These results indicate that kuwanon G prevents the pathological progression of allergic asthma through the inhibition of lung destruction by inflammation and immune stimulation.

Prophylactic effectiveness of suplatast tosilate in children with asthma symptoms in the autumn: a pilot study

BACKGROUND

Exacerbations of bronchial asthma usually occur in the autumn. To our knowledge, however, the effectiveness of drugs for preventing exacerbations of asthma in the autumn has not been studied previously, except for leukotriene receptor antagonists and Omalizmab.

METHODS

This study compared the prophylactic effectiveness of suplatast tosilate with that of mequitazine in children with asthma symptoms, which is usually exacerbated in the autumn. The study group comprised 27 children aged 2 to 15 years who required treatment for asthmatic attacks during the past year and tested positive at least for mite allergen in the preceding autumn. The subjects were randomly assigned to receive either suplatast or mequitazine. The primary endpoint of this study was the number of days without symptoms during the 8 weeks of treatment. In addition, the Japanese Pediatric Asthma Control Program (JPAC) scores were also recorded every 2 weeks in each group.

RESULTS

Overall, 14 patients received suplatast, and 13 received mequitazine for 8 weeks from September through early October. During follow-up, the number of days without symptoms and the total JPAC scores did not differ significantly between the groups. However, as compared with weeks 1 to 2 of treatment, the mean number of days without symptoms during weeks 7 to 8 increased significantly in only the suplatast group (8.6 vs. 11.5 days; p = 0.004).

CONCLUSIONS

Our results suggest that short-term additional treatment with suplatast is useful for preventing asthma symptoms in children with asthma, which is usually exacerbated in the autumn.

Pediatric allergy and immunology in Japan

The Japanese Society of Pediatric Allergy and Clinical Immunology (JSPACI) was started in 1966 and currently has 3613 members as of August 1, 2012. The number of pediatricians specializing in allergies who have been certified by the Japanese Society of Allergology is 817. Among these, there are 125 training directors and training facilities for allergy and clinical immunology. The JSPACI first published an asthma guideline specific for children in 2000, and this has been revised every 3 yrs, contributing to better control of pediatric asthma. Food allergy management guidelines were first developed in 2005, which have helped to improve the care of food allergy patients. Among 514 pediatric training programs by the Japanese Society of Pediatrics, there are 312 facilities routinely performing oral food challenges. Among these, there were already 53 facilities performing oral immunotherapy at the end of 2011, treating 1400 cases of food allergy. The prevalence of pediatric allergic diseases has increased in Japan over the past 50 yrs. A number of International Study of Asthma and Allergies in Childhood surveys have been conducted in the past at specific times. The prevalence of wheezing among children aged 13-14 yrs in 2002 was 13.0%. Multi-year surveys found a 1.5- to 2-fold increase every 10 yrs until 2002. However, according to the latest data in 2012, asthma prevalence seems to have slightly decreased in Japan. Food allergy mainly associated with infantile atopic eczema among infants younger than 1 yr of age is the most common form as with other developed countries. The estimated food allergy prevalence based on data from several surveys is 5-10% among infants (0-6 yrs) and 1-2% among schoolchildren (6-15 yrs). A variety of patients suffering from primary deficiency syndrome have been actively analyzed. Previously, antibody defects and well-defined syndromes with immunodeficiency were analyzed, but recent research is focusing on not only acquired immune disorders but also on innate immune disorders. In contrast to the widespread use of oral immunotherapy, one immediate issue is to develop and reassess subcutaneous and sublingual immunotherapies for mite and Japanese cedar pollen antigens that have been disused in Japan since the 1990s.

Suplatast tosilate ameliorates airway hyperreactivity and inflammation through inhibition of the GATA‑3/IL‑5 signaling pathway in asthmatic rats

Airway hyperreactivity and inflammation are important factors in the aggravation of lung function. Suplatast tosilate (IPD) is a novel and unique anti‑asthma clinical compound. However, the mechanisms of IPD action in the inhibition of asthma remain to be elucidated. The present study aimed to investigate the role of the GATA binding protein 3 (GATA‑3)/interleukin (IL)‑5 signaling pathway in IPD‑induced inhibition of asthma. Sprague‑Dawley rats were sensitized by intraperitoneal injection with ovalbumin (OVA) to establish an animal model of asthma. IPD was administered continuously (C‑IPD) or at a later stage (L‑IPD). Budesonide (BUD) was used as a positive control. Airway resistance and the expression of genes at the mRNA and protein levels were measured. Morphological changes in lung tissue and the percentage of eosinophils (EOS) in peripheral blood were observed and correlation analysis was performed. The results revealed that sensitization by OVA significantly increased airway resistance and the percentage of EOS in peripheral blood and induced significant inflammatory changes in lung tissue, as demonstrated by thick epithelium, goblet cell hyperplasia and submucosal cell infiltration. In addition, sensitization by OVA was found to markedly upregulate IL‑5 mRNA and protein expression. Airway resistance was found to positively correlate with the expression of IL‑5 in the rat lung tissues. Sensitization by OVA was also observed to markedly enhance GATA‑3 protein expression and GATA‑3 levels were found to positively correlate with airway resistance and IL‑5 levels. Similar to the effect of BUD, treatment with C‑IPD or L‑IPD was found to significantly attenuate OVA‑induced increases in airway resistance and the percentage of EOS in peripheral blood. Notably, treatment with C‑IPD or L‑IPD markedly reduced the OVA-induced expression of IL‑5 and GATA‑3. In the present study, IPD intervention was demonstrated to ameliorate airway hyperreactivity and inflammation and the mechanisms may involve inhibition of the GATA‑3/IL‑5 signaling pathway.

Inhibition of common cold-induced aggravation of childhood asthma by leukotriene receptor antagonists

BACKGROUND

Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold.

METHODS

Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged <4 years old and 4 to 11 years old, and an Asthma Control Test (ACT) for patients aged 12 to 15 years old.

RESULTS

The status of asthma control did not differ among the age groups. The prevalence of common cold and aggravation of asthma were significantly higher in patients aged <4 years old. Control of asthma following common cold-induced aggravation was significantly less effective in patients aged <4 years old compared to those aged ≥4 years old. In patients aged <4 years old with a common cold, asthma control was significantly more effective for those treated with leukotriene receptor antagonists (LTRAs) compared to treatment without LTRAs. Asthma control did not differ between patients who did or did not take inhaled corticosteroids or long-acting β2 stimulants.

CONCLUSIONS

These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.

Recent research and developmental strategy of anti-asthma drugs

Extensive research over the past decade has provided information about the pharmacotherapy of bronchial asthma (BA). Anti-asthma drugs are classified into two categories: relievers (for the relief of asthma attack symptoms) and controllers (for the prevention of asthma symptoms). This paper aims to review the recent advancements of anti-asthma drugs that are controller medicines. The controllers mainly act on immune and inflammatory responses in BA development. 1) Immunomodulators. Drugs that act on the immune response are classified into two categories: immunosuppressors and immunomodulators, including immunopotentiators. The immunomodulation of the Th1 and Th2 imbalance is the first strategy of the controller because allergic BA is thought to be caused by Th2-polarized immunity. Suplatast is a novel immunomodulator that can adjust the imbalance in the Th1/Th2 immune response and shows clear clinical efficacy against BA. The immunomodulator approach has shifted from a more theoretical and conceptual model to one supported by evidence of clinical efficacy.2) Anti-inflammatory agents. Corticosteroids,mast cell stabilizers and autacoid inhibitors are anti-inflammatory agents for BA. The clinical superiority of the combined therapy of inhaled corticosteroids and long-acting beta2 agonists is evident. This combined therapy shows a potent synergic anti-inflammatory effect compared to the effect by corticosteroids alone. Currently, the anti-inflammatory agents for BA under development are drugs affecting lipid mediators. The prostaglandin (PG) D2 antagonist, PGE2, EP3 agonist and PGI2 agonist are being considered in addition to well-established leukotriene and thromboxane A2 inhibitors. New development strategies and therapeutics for controllers are described in this review.

Increase effect of transforming growth factor on eotaxin production by normal cultured dermal fibroblasts stimulated with interleukin-4: inhibitory effect of suplatast tosilate on eotaxin production

Eotaxin plays a central role in the development of allergic disease, including atopic dermatitis, asthma, and nasal allergy. Interleukin (IL)-4 induces eotaxin production in normal human dermal fibroblasts. On the other hands, Transforming growth factor-beta (TGF-beta), a multifunctional regulatory cytokine, affects many biological functions, including fibroblast growth and differentiation and Th2 cytokine regulation. In this study, we investigated the effect of TGF-beta on IL-4-induced eotaxin production by normal human fibroblasts, as well as the effect of suplatast tosilate, an antiallergic drug that selectively inhibits Th2 cytokine production. Dermal fibroblast treatment with IL-4 and TGF-beta for 24 h increased eotaxin production and expression of eotaxin mRNA, as measured by enzyme-linked immunosorbent assay (ELISA) and reverse-transcriptase polymerase chain reaction (RT-PCR), respectively. TGF-beta synergistically up-regulated eotaxin production and eotaxin mRNA expression when stimulated with IL-4. Suplatast tosilate dose-dependently inhibited eotaxin production induced by IL-4 or IL-4 plus TGF-beta. These results suggest that TGF-beta may regulate skin allergic inflammation by up-regulating eotaxin production in dermal fibroblasts. Suplatast tosilate might suppress this inflammation by inhibiting eotaxin production.

Early intervention for infantile and childhood asthma

Asthma is a chronic airway inflammatory disease and it is accepted that early initiation of anti-inflammatory medication is beneficial for adult asthma. Pathological and epidemiological studies suggested that early intervention with anti-inflammatory drugs such as inhaled corticosteroids (ICS) should take place before preschool age, possibly between 1 and 3 years of age. However, the effect of early intervention using ICS in young children is considered controversial as several clinical studies have suggested that ICS does not alter the natural history of asthma in young children. Although there is limited and some negative evidence for the effect of ICS in young children, ICS remains the most effective medication for controlling asthma of the currently available drugs for all ages. Therefore, pediatricians should prescribe ICS to control the active symptoms of asthma, owing to the well-known, beneficial effects of ICS on decreasing the symptom burden of young children with asthma.

Immunomodulators in asthma therapy

New developments in the field of allergy and immunology have yielded a variety of novel therapeutic approaches in recent years, and more agents are at the clinical trial stage. Among the therapeutic approaches discussed in this review are Toll-like receptor agonists, immunostimulatory oligodeoxynucleotides, orally and parenterally administered cytokine blockers, and specific cytokine receptor antagonists. Transcription factor modulators targeting syk kinase, peroxisome proliferator-activated receptor-gamma, and nuclear factor-kappaB are also being evaluated in the treatment of asthma. The anti-IgE monoclonal antibody omalizumab has established effectiveness in patients with allergic asthma, but the criteria for selecting patients who are most likely to benefit from it are less clear. This review summarizes data from human clinical trials with immunomodulators to discuss the rationale for their use, their efficacy, and adverse events associated with them.

Suplatast tosilate inhibits histamine signaling by direct and indirect down-regulation of histamine H1 receptor gene expression through suppression of histidine decarboxylase and IL-4 gene transcriptions

Allergic rhinitis (AR) is an inflammatory disorder typified by symptoms such as sneezing, congestion, and rhinorrhea. Histamine plays important roles in eliciting AR symptoms. Up-regulation of the histamine H(1) receptor (H1R) and histidine decarboxylase (HDC) mRNAs was observed in AR patients. Th2 cytokines are also involved in the pathogenesis of AR. We examined the effect of suplatast tosilate on nasal symptoms, and H1R, HDC, and IL-4 gene expression using toluene-2,4-diisocyanate (TDI)-sensitized rats and HeLa cells expressing endogenous H1R. Provocation with TDI increased nasal symptoms, HDC activity, the histamine content of nasal lavage fluid, and the expression of H1R, HDC, and IL-4 mRNAs in TDI-sensitized rats. Pretreatment with suplatast for 2 wk significantly suppressed TDI-induced nasal symptoms and elevation of H1R, HDC, and IL-4 mRNAs. Suplatast also suppressed HDC activity in the nasal mucosa and the histamine content of the nasal lavage fluid. Bilateral injection of IL-4 into the nasal cavity of normal rats up-regulated H1R mRNA, while intranasal application of histamine up-regulated IL-4 mRNA. Suplatast suppressed IL-4-induced up-regulation of H1R mRNA in HeLa cells. However, it did not inhibit histamine-induced H1R mRNA elevation. These results suggest that suplatast alleviates nasal symptoms by inhibiting histamine signaling in TDI-sensitized rats through the suppression of histamine- and IL-4-induced H1R gene expression by the inhibitions of HDC and IL-4 gene transcriptions, respectively.