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Food Allergy Herbal Formula-1 (FAHF-1) blocks peanut-induced anaphylaxis in a mouse model.
Xiu-Min Li, Hugh Sampson et al, New York, NY and Baltimore
Background: Peanut allergy is a major cause of fatal and near fatal anaphylactic reactions to foods. There is no curative therapy for this condition. Traditional Chinese medicines have been reported to have antiallergic properties, which might be useful in treating peanut allergy.
Objective: The purpose of this study was to investigate the effects of a Chinese herbal formula, FAHF-1, on peanut anaphylactic reactions in a mouse model of peanut allergy.
Methods: Mice were sensitized with freshly ground whole peanut in the presence of cholera toxin and boosted 1 and 3 weeks later. FAHF-1 treatment was initiated 1 week later and continued for 7 weeks. After treatment mice were challenged with peanut, and anaphylactic symptoms, body temperatures, and plasma histamine and IgE levels were measured. T-cell proliferative responses and cytokine production were also determined.
Results: FAHF-1 completely blocked peanut-induced anaphylactic symptoms and markedly reduced mast cell degranulation and histamine release. Peanut-specific serum IgE levels were significantly reduced by 2 weeks of treatment at the time of challenge, and they remained lower 4 weeks after discontinuation of treatment. FAHF-1 significantly reduced peanut-induced lymphocyte proliferation as well as IL-4, Il-5, and IL-13 synthesis but not of IFN-gamma synthesis. No toxic effects on liver or kidney functions were observed, nor was there any overall immune suppression.
Conclusion: FAHF-1 protected peanut-sensitized mice from anaphylactic reactions and significantly reversed established IgE-mediated peanut allergy. This suggests that FAHF-1 might prove valuable for the treatment of peanut allergy.
Reference: J Allergy Clin Immunol 2001; 108:639-46
Dog exposure in infancy decreases the subsequent risk of frequent wheeze but not atopy
Sami t. Remes et al., Tucson, Arizona and Kuopio, Finland
Background: Influence of household pets in the development of childhood asthma or atopy has been controversial.
Objective: The purpose of this study was to investigate whether pet exposure in early life decreases the subsequent risk of frequent wheeze and/or allergic sensitization.
Methods: This was a prospective observational birth cohort study. The setting was a large health maintenance organization in Tucson, Arizona; the subjects were a population sample of 1246 newborns enrolled at birth and followed prospectively to age 13 years. The main outcome measures were as follows: time to first report of wheezing (>3 episodes in the past year), skin prick test reactivity at 6 years and 11 years of age, and total serum IgE at 9 months, 6 years, and 11 years of age.
Results: Children living in households with >1 indoor dog at birth were less likely to develop frequent wheeze than those not having indoor dogs (p=.004). This inverse association was confined to children without parental asthma (hazard ratio = 0.47; P <.001 [cox regression]) and was not evident for children with parental asthma (hazard ratio = 0.96; P = .97). Adjustment by potential confounders did not change the results. Indoor cat exposure was not significantly associated with the risk of frequent wheezing. Neither cat exposure in early life nor dog exposure in early life was associated with skin prick test reactivity or total serum IgE at any age.
Conclusion: Dog exposure in early life might prevent the development of asthma-like symptoms, at least in low-risk children with no family history of asthma. Nevertheless, early pet exposure does not seem to significantly influence the development of allergic sensitization.
Reference: J Allergy Clin Immunol 2001; 108: 509-15 (October 2001)
Genes and environment in asthma: a study of 4 year old twins
G Koeppen-Schomerus et al, Univ Southampton, UK
Background: Although the genetic and environmental factors of asthma have been investigated in adolescence and adulthood, no previous studies focused on the early development of asthma.
Aims: To test, in a large sample of 4 year old twins, the hypothesis derived from the literature on adolescents and adults that genetic influences are substantial and shared environmental influences are modest.
Methods: The sample consisted of 4910 twin pairs who were born in England and Wales in 1994 and 1995. Data on asthma status were obtained from the twins' parents by postal questionnaire.
Results: Univarate parameter estimates derived from model fitting were 68% heritability, 13% shared environment, and 19% non-shared environment.
Conclusions: Our findings suggest that asthma is highly heritable in 4 year olds, whereas shared environmental influences are not statistically significant.
Reference: Arch Dis Child 2001; 85: 398-400
Effects of inhaled glucocorticoids on Bone Density in Premenopausal Women
Elliot Israel et al Bringham and Women's Hospital, Boston
Background: Inhaled steroids are the most commonly used medications for long-term treatment of patients with asthma. Whether long-term therapy with inhaled steroid reduces bone mass, as oral steroids does, is controversial. In a three-year prospective study, they examined the relation between the dose of inhaled steroids and the rate of bone loss in premenopausal women with asthma.
Methods: They studied 109 premenopausal women, 18 to 45 years of age, who had asthma and no known conditions that cause bone loss and who were treated with inhaled steroids. They measured bone density by dual-photon absorptiometry at base line, at six months, and at one, two, and three years. Serum osteocalcin and parathyroid hormone and urinary N-telopeptide, cortisol, and calcium excretion were measured serially. They measured inhaled steroids use by means of monthly diaries, supported by the use of an automated actuator-monitoring device.
Results: Inhaled steroid therapy was associated with a dose-related decline in bone density at both the total hip and trochanter of 0.00044g per square centimeter per puff per year of treatment (P=0.01 and P=.005, respectively). No dose-related effect was noted at the femoral neck or the spine. Even after the exclusion of all women who received oral or parenteral steroids at any time during the study, there was still an association between the decline in bone density and the number of puffs per year of use. Serum and urinary markers of bone turnover or adrenal function did not predict the degree of bone loss.
Conclusion: Inhaled steroids lead to a dose-related loss of bone at the hip in premenopausal women.
Reference: NEJM Volume 345: 941-947 September 27, 2001
A prospective study of association between home gas appliance use during infancy and subsequent dust mite sensitization and lung function in childhood
A. L. Ponsonby, A Kemp et al Univ of Tasmania, Hobart Australia
Background: Home gas appliance use may be associated with childhood respiratory illness but prospective data on the relationship between infant exposure and the development of childhood allergic disease has not been readily available.
Objectives: (a) To determine if home gas appliance use is associated with increased risk of house dust mite (HDM) sensitization.
(b) To examine whether any association between current home gas use and airway obstruction is influenced by HDM sensitization.
Methods: Design: an 8-year follow-up birth cohort study of children born during 1988 and 1989. Participants: a population-based sample (n=498) of children who participated in the Tasmanian Infant Health Survey (TIHS) and resided in Northern Tasmania in 1997 (84% of eligible children). Main outcome measures: (a) Skin prick test reaction to 9 allergens, including House dust mites (Der p 1 and Der f 1). (b) Spirometric lung function indices, including forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC).
Results: The relative risk for home gas appliance use at 1 month of age and HDM sensitization was 1.98 (1.04, 3.79) in a cohort analysis with confounder matching. Current home gas use was related to a stronger (P=0.006) reduction in FEV1 : FVC ratio among HDM-sensitive children (adjusted difference - 6.2% ( - 10.0 to - 2.4) than non-HDM-sensitive children (adjusted difference - 0.3% (- 2.5 ti 1.8).
Conclusion: Indoor polutants from gas combustion may increase the likelihood of initial sensitization to HDM and play a role in the development of atopic asthma. HDM-sensitized children may be more vulnerable to indoor pollutant-induced airway obstruction. The ability of this study to detect such effects may partly reflect unflued gas appliance use among this sample.
Reference: Clinical and Experimental Allergy, Vol. 31, pp. 1544-1552
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