Abstract
BackgroundRecently, academic studies suggest that global growth of airway allergic disease has a close association with dietary changes including reduced consumption of fiber. Therefore, appropriate dietary fiber supplementation might be potential to prevent airway allergic disease (AAD).ObjectiveWe investigated whether dietary fiber intake suppressed the induction of AAD and tried to elucidate the possible underlying mechanisms.MethodsThe control mice and AAD model mice fed with 4% standard-fiber chow, while low-fiber group of mice fed with a 1.75% low-fiber chow. The two fiber-intervened groups including mice, apart from a standard-fiber diet, were also intragastric (i.g.) administrated daily with poorly fermentable cellulose or readily fermentable pectin (0.4% of daily body weight), respectively. All animals except normal mice were sensitized and challenged with ovalbumin (OVA) to induce airway allergic inflammation. Hallmarks of AAD were examined by histological analysis and ELISA. The variation in intestinal bacterial composition was assessed by qualitative analysis of 16S ribosomal DNA (rDNA) content in fecal samples using real-time PCR.ResultsLow-fiber diet aggravated inflammatory response in ovalbumin-induced allergic mice, whereas dietary fiber intake significantly suppressed the allergic responses, attenuated allergic symptoms of nasal rubbing and sneezing, decreased the pathology of eosinophil infiltration and goblet cell metaplasia in the nasal mucosa and lung, inhibited serum OVA-specific IgE levels, and lowered the levels of Th2 cytokines in NALF and BALF, but, increased Th1 (IFN-γ) cytokines. Additionally, dietary fiber intake also increased the proportion of Bacteroidetes and Actinobacteria, and decreased Firmicutes and Proteobacteria. Levels of probiotic bacteria, such as Lactobacillus and Bifidobacterium, were upgraded significantly.ConclusionLong-term deficiency of dietary fiber intake increases the susceptibility to AAD, whereas proper fiber supplementation promotes effectively the balance of Th1/Th2 immunity and then attenuates allergic inflammatory responses significantly, as well as optimizes the structure of intestinal microbiota, which suggests potential for novel preventive and therapeutic intervention.
Highlights
Allergic airway diseases (AAD), such as allergic rhinitis, asthma, and so forth, are reversible and chronic atopic disorders, leading to substantial global financial and medical burden [1,2]
Long-term deficiency of dietary fiber intake increases the susceptibility to AAD, whereas proper fiber supplementation promotes effectively the balance of Th1/Th2 immunity and attenuates allergic inflammatory responses significantly, as well as optimizes the structure of intestinal microbiota, which suggests potential for novel preventive and therapeutic intervention
In order to determine the role of dietary fiber in allergy, we first measured the frequency of allergic symptoms per mouse[24]
Summary
Allergic airway diseases (AAD), such as allergic rhinitis, asthma, and so forth, are reversible and chronic atopic disorders, leading to substantial global financial and medical burden [1,2]. Epidemiologic surveys suggest that the incidence of allergic rhinitis and asthma increased worldwide, especially in the West [1,6]. Studies have increasingly found that this increase of allergic diseases was associated closely with dietary changes, especially chronic high-fat and low-fiber diets over the past decades [7,8]. Academic studies suggest that global growth of airway allergic disease has a close association with dietary changes including reduced consumption of fiber. Appropriate dietary fiber supplementation might be potential to prevent airway allergic disease (AAD)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
