Diet as a Risk Factor for Asthma

Weiss, Scott T.

doi:10.1002/9780470515334.ch16

Cited by 30 publications

(34 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Clinical studies indicate that higher intake of a-tocopherol may confer a modest protective effect on adult-onset asthma and beneficial effect on lung function (FEV 1 ) or wheeze in studies in Finland and Italy but not in the United States or the Netherlands (37)(38)(39)(40)(41). In contrast, a very high dose of an acetateconjugated d-a-tocopherol (1,500 IU, which is 1,006 mg) to subjects with mild atopic asthma in the United States for 16 weeks resulted in increased plasma a-tocopherol, decreased plasma g-tocopherol, and improved airway responsiveness to methacholine challenge (42).…”

mentioning

confidence: 99%

Two Faces of Vitamin E in the Lung

Cook‐Mills

Abdala-Valencia

Hartert

2013

Am J Respir Crit Care Med

View full text Add to dashboard Cite

Asthma and allergic lung disease occur as complex environmental and genetic interactions. Clinical studies of asthma indicate a number of protective dietary factors, such as vitamin E, on asthma risk. However, these studies have had seemingly conflicting outcomes. In this perspective, we discuss opposing regulatory effects of tocopherol isoforms of vitamin E, mechanisms for tocopherol isoform regulation of allergic lung inflammation, association of vitamin E isoforms with outcomes in clinical studies, and how the variation in global prevalence of asthma may be explained, at least in part, by vitamin E isoforms.Keywords: asthma; a-tocopherol; g-tocopherol; human; mouse Asthma and allergic lung disease occur as complex environmental and genetic interactions (1). The World Health Organization has reported that the prevalence of asthma from 1950 to the present has increased in many countries, including countries with high rates of asthma, intermediate rates of asthma, or low rates of asthma (2-4). The marked differences in rates of asthma within countries, in migrating populations, and over relatively short periods of time support an important role of the local environment, such as diet, in asthma inception. Prospective epidemiological studies, observational cross-sectional studies, and some randomized prevention trials have demonstrated the impact of a number of protective dietary factors, such as vitamin E, on asthma risk. However, these studies have had seemingly conflicting outcomes. We need to determine why there are low rates of allergic disease in developing countries and better understand the differences in diet and lifestyle that may really underpin allergic disease. One environmental change over the past 40 years has been an increase in the g-tocopherol isoform of vitamin E in the diet and in infant formulas (5, 6). We recently demonstrated that g-tocopherol increases allergic lung inflammation in mice (6)(7)(8). In this perspective, we discuss why we have yet to uncover the complex and potentially protective effects of isoforms of vitamin E on asthma in humans and in animal models of lung inflammation. We also review mechanisms for tocopherol isoform regulation of allergic lung inflammation in animals and discuss how the variation in global prevalence of asthma may be explained, at least in part, by country-specific plasma g-tocopherol differences.Vitamin E consists of natural isoforms and synthetic racemic isoforms. The eight natural isomers are d-a-, d-b-, d-g-, d-d-tocopherol and d-a-, d-b-, d-g-, d-d-tocotrienol. Plants synthesize the natural isoforms from tyrosine and chlorophyll (9). Then, these tocols are consumed in the diet from plant lipids. Mammals do not interconvert the tocopherol isoforms. The most abundant isoforms are a-tocopherol and g-tocopherol, which differ by one methyl group ( Figure 1A). There are approximately 10-fold higher tissue concentrations of a-tocopherol than g-tocopherol due to preferential transfer of a-tocopherol in the liver by a-tocopherol transfer protein and due to ...

show abstract

mentioning

confidence: 99%

Two Faces of Vitamin E in the Lung

Cook‐Mills

Abdala-Valencia

Hartert

2013

Am J Respir Crit Care Med

View full text Add to dashboard Cite

show abstract

“…Mice were initially sensitized i.p. with 100 mg of RW extract (Hollister-Stier Canada Co., Toronto, Canada) in 2mg Al(OH) 3 (alum) adjuvant. On day 14 postsensitization, mice were challenged intranasally (i.n.)…”

Section: Allergen Sensitization and Challengementioning

confidence: 99%

“…This allergy epidemic has been attributed to various factors, such as pollution, changes of diet, allergen exposure, and more recently, overly increased hygiene (2)(3)(4). The so called hygiene hypothesis proposes that the reduced rate of exposure to infectious agents, especially in developed areas, is directly related to the increase of allergic diseases, such as allergic asthma, atopic eczema, and rhinitis, because certain infections have an inhibitory effect on allergic reactions (5-7).…”

mentioning

confidence: 99%

Dendritic Cells from Mycobacteria-Infected Mice Inhibits Established Allergic Airway Inflammatory Responses to Ragweed via IL-10– and IL-12–Secreting Mechanisms

Bilenki

Gao

Wang

et al. 2010

The Journal of Immunology

View full text Add to dashboard Cite

Previous studies have demonstrated that Mycobacterium bovis bacillus Calmette-Guerin (BCG) infection can inhibit de novo and established allergen-induced asthma-like responses. The aim of this study was to examine the role of dendritic cells (DCs) in BCG infection-mediated inhibition of established allergy to a common environmental allergen—ragweed. The results showed that adoptive transfer of DCs from BCG-infected mice (DC[BCG]), in contrast to DCs from naive mice (DC[naive]), significantly inhibited established allergic airway eosinophilia and mucus overproduction. The inhibitory effect was correlated with alterations of allergen-driven cytokine and chemokine production as well as VCAM-1 expression in the lung. Flow cytometric analysis showed higher surface expression of CD8α and costimulatory markers in DC(BCG) than in DC(naive). Moreover, DC(BCG) produced significantly higher levels of IL-10 and IL-12 and expressed higher levels of TLRs than did DC(naive). Furthermore, blockade of IL-10 or IL-12 significantly reversed the inhibitory effect of DC(BCG) on established allergic airway inflammation and Th2 cytokine responses. These findings suggest that DCs play a crucial role in infection-mediated inhibition of established allergic responses, and IL-10 and IL-12 production by these DCs may be a major mechanism for the inhibition.

show abstract

“…Det er holdepunkter for at et høyt inntak av antioksydanter (f.eks. vitamin C, umettede fettsyrer) kan ha en forebyggende effekt (49). Det er et stort behov for forskning på dette området.…”

Section: Kostholdunclassified

“…Amming kan ha en gunstig forebyggende effekt på utvikling av astma og allergi (49,63). En ny studie viser imidlertid at amming av sterkt atopiske barn (barn med atopisk eksem) i enkelte tilfelle kan forverre sykdommen (63).…”

Section: Astma Og Ammingunclassified

Astma

Nystad¹

2009

Nor J Epidemiol

View full text Add to dashboard Cite

Telefon: 22 04 23 94 telefax: 22 04 23 51 E-post: wenche.nystad@folkehelsa.no INNLEDNINGAstma er betegnelsen på et syndrom med flere undergrupper som er blant de hyppigste sykdommene i Norge (1). Nyere befolkningsstudier viser også at antall personer som rapporterer at de har astma øker (2-7). Det betyr at astma i fremtiden vil vaere hyppigere blant norske kvinner enn tidligere. I den forbindelse er det blant annet viktig å kjenne til hvordan astmaen kan virke på graviditeten, betydningen av morens astma på fosteret, fødselens forløp og barnets tilstand før og etter fødselen. I tillegg kan det vaere vesentlig å vaere bevisst at enkelte kvinner kan ha astmaplager som påvirkes av menstruasjonssyklus (8,9). Unge kvinner med astma kan også ha en rekke spørsmål som knytter seg til astma og seksuell aktivitet samt bruk av prevensjon. HVA ER ASTMA?Astma er en klinisk diagnose som baserer seg på informasjon om gjentatte episoder av hoste og/eller pusteproblemer i form av tetthet, pipende eller tung pust. Ytringsformene er mange. Det er gjort flere forsøk på å definere diagnosen naermere. Siden 1959 har alle definisjonene vektlagt at det som kjennetegner astma er en utbredt og variabel forsnevring av luftveiene (luftveisobstruksjon) (10-12). I astmaens natur ligger denne variabiliteten. Det vil også si at den enkelte pasient kan ha gode og dårlige perioder, og at sykdommen kan arte seg forskjellig fra pasient til pasient.I dag regnes astma som en betennelsessykdom i luftveiene (12). Hos følsomme individer forårsaker den utbredte betennelsen luftveissymptomer som er assosiert med variabel luftveisobstruksjon. Denne betennelsen fører til økt følsomhet i luftveiene (økt bronkial reaktivitet) overfor en rekke stimuli.Astma kan svaert forenklet deles i allergisk og ikkeallergisk astma. Uspesifikke agens som kan gi symptomer hos de fleste astmatikere, såvel allergiske som ikke-allergiske, er anstrengelse, kulde, tobakksrøyk, infeksjoner, sterke lukter, m.m. Med uspesifikk menes her stimuli som leder til obstruksjon gjennom ikkeallergiske mekanismer. For pasienter med allergisk astma fremkalles obstruksjonen også gjennom spesifikke stimuli som for eksempel bjørkepollen, gresspollen, pelsdyr, muggsopp m.m. Med spesifikk menes her stimuli som leder til obstruksjon gjennom allergiske mekanismer.Å stille diagnosen astma kan vaere enkelt når man ser det akutte anfallet eller får beskrevet en typisk sykehistorie. Når mange personer skal undersøkes som i befolkningsstudier må man ty til enkle operasjonelle definisjoner. Hvordan måle astma?Flere operasjonelle definisjoner på astma kan benyttes. Det er vanlig å spørre om omfanget av forskjellige typer pusteproblemer (13,14). Andre kriterier basert på lungefunksjonsmåling målinger av følsomheten i luftveiene og allergitest benyttes også (13,14). Det er imidlertid flere problemer som knytter seg til det å definere astma i befolkningsundersøkelser. Det er vanskelig å komme frem til en spesifikk definisjon av sykdommen som klart avgrenser den fra andre lignende luftveissykdommer. For det an...

show abstract

Diet as a Risk Factor for Asthma

Cited by 30 publications

References 44 publications

Two Faces of Vitamin E in the Lung

Two Faces of Vitamin E in the Lung

Dendritic Cells from Mycobacteria-Infected Mice Inhibits Established Allergic Airway Inflammatory Responses to Ragweed via IL-10– and IL-12–Secreting Mechanisms

Astma

Contact Info

Product

Resources

About