Probiotics and Insulin Resistance in Obese Asthmatics

(1a) For airway microbiome analyses, nasal wash samples will be used as surrogates. Nasal wash will be collected from subjects at baseline and 12 weeks. Rectal swab will be collected using Fecal swab kit (COPAN, Thermofisher) and samples prepared for microbiome analysis as above. Microbial genomic DNA from the samples will be isolated using the DNA isolation kit from Zymo Research. (1b) The samples obtained in Aim 1a will be used for metabolomics analyses, both gut and airway samples. Untargeted metabolomics utilizing Liquid Chromatography coupled with mass spectrometry will be performed at UAB Metabolomics Core and metabolites including SCFA, acetate, lactate, ethanol, succinate, formate and enterolactone will be analyzed and quantitated. For both above aims, changes over the 12 weeks will be compared between groups.

(2a) Classification of obesity, waist circumference and waist-to-hip ratio (WHR) will be determined according to the WHO definitions. At baseline and at 12 weeks post-probiotic administration, glucose, Leptin and lipid profile panels will be analyzed from plasma prepared from whole blood collected from fasting individuals. (2b) The recruited subjects will have a HOMA-IR \>5. At baseline and at 12 weeks after probiotics/placebo administration, potential change in insulin sensitivity will be calculated as described in methods above. (2c) Determine if probiotic-mediated changes in leptin, weight gain and insulin sensitivity correlates with airway metabolome alterations compared to placebo controls. Unique airway metabolome signatures comparing probiotics and placebo control groups will be correlated with lowered leptin levels, increased weight loss and increased insulin sensitivity. For th…

(3a) At baseline and at 12 weeks post-probiotics or placebo administration, asthma biomarkers such as FeNO, IgE, peripheral neutrophils and eosinophils as well as proinflammatory plasma cytokines (IL-6, TNF-α, IL-1β) will be measured. Innate and adaptive immune cells will be enumerated by multiparameter flow cytometry in peripheral blood. These biomarkers will be correlated with changes in microbiome/metabolome identified above in Aim 1 between groups. (3b) At baseline and at 12 weeks post-probiotics or placebo administration, spirometry (FEV1 and FVC), exacerbations/steroid exposure, asthma control test (ACT) and asthma control questionnaire, Asthma Quality of Life Questionnaire (AQLQ) will be performed. Comparison in differences will be made between the groups.