title: Soluble Fibre Meal Challenge Reduces Airway Inflammation and Expression of GPR43 and GPR41 in Asthma.
abstract: Short chain fatty acids (SCFAs) are produced following the fermentation of soluble fibre by gut bacteria. In animal models, both dietary fibre and SCFAs have demonstrated anti-inflammatory effects via the activation of free fatty acid receptors, such as G protein-coupled receptor 41 and 43 (GPR41 and GPR43). This pilot study examined the acute effect of a single dose of soluble fibre on airway inflammation-including changes in gene expression of free fatty acid receptors-in asthma. Adults with stable asthma consumed a soluble fibre meal (n= 17) containing 3.5 g inulin and probiotics, or a control meal (n= 12) of simple carbohydrates. Exhaled nitric oxide (eNO) was measured and induced sputum was collected at 0 and 4 h for differential cell counts, measurement of interleukin-8 (IL-8) protein concentration, and GPR41 and GPR43 gene expression. At 4 h after meal consumption, airway inflammation biomarkers, including sputum total cell count, neutrophils, macrophages, lymphocytes, sputum IL-8, and eNO significantly decreased compared to baseline in the soluble fibre group only. This corresponded with upregulated GPR41 and GPR43 sputum gene expression and improved lung function in the soluble fibre group alone. Soluble fibre has acute anti-inflammatory effects in asthmatic airways. Long-term effects of soluble fibre as an anti-inflammatory therapy in asthma warrants further investigation.
authors.affiliation: Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, Callaghan, NSW 2308, Australia. isabel_h90@hotmail.com.
authors.forename: Isabel
authors.initials: I
authors.lastname: Halnes
authors.affiliation: Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, Callaghan, NSW 2308, Australia. Katherine.baines@newcastle.edu.au.
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Baines
authors.affiliation: Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, Callaghan, NSW 2308, Australia. bronwyn.berthon@newcastle.edu.au.
authors.forename: Bronwyn S
authors.initials: BS
authors.lastname: Berthon
authors.affiliation: School of Health Sciences, University of Newcastle, Callaghan, NSW 2305, Australia. lesley.wicks@newcastle.edu.au.
authors.forename: Lesley K
authors.initials: LK
authors.lastname: MacDonald-Wicks
authors.affiliation: Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, Callaghan, NSW 2308, Australia. peter.gibson@newcastle.edu.au.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Gibson
authors.affiliation: Centre for Healthy Lungs, Hunter Medical Research Institute, University of Newcastle, Callaghan, NSW 2308, Australia. lisa.wood@newcastle.edu.au.
authors.forename: Lisa G
authors.initials: LG
authors.lastname: Wood
mesh_terms: D000328:Adult; D001249:Asthma / Q000178:diet therapy* / Q000235:genetics; D015992:Body Mass Index; D001835:Body Weight; D004043:Dietary Fiber / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000517:prevention & control*; D016209:Interleukin-8 / Q000378:metabolism; D007444:Inulin / Q000008:administration & dosage; D008264:Macrophages / Q000378:metabolism; D008297:Male; D062407:Meals; D008875:Middle Aged; D009504:Neutrophils / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D010865:Pilot Projects; D019936:Probiotics / Q000008:administration & dosage; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D013183:Sputum / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D004043:Dietary Fiber; D016209:Interleukin-8; D007444:Inulin; D009569:Nitric Oxide; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C508606:CXCL8 protein, human; C473103:FFAR2 protein, human; C106262:FFAR3 protein, human
keywords: G-protein coupled receptor; asthma; inflammation; prebiotics; short chain fatty acids