Diao W, Labaki WW, Han MK, et al. - Given that the mechanistic underpinnings that contribute to chronic obstructive pulmonary disease (COPD) pathogenesis may be understood with the help of metabolomics and gender and body mass index (BMI) may influence blood metabolomics, researchers investigated male smokers with and without COPD having a narrow BMI range for metabolomic variability. They discovered and quantified 28 metabolites. COPD patients vs non-COPD smokers had reduced creatine, glycine, histidine, and threonine levels. An inverse correlation of concentrations of these metabolites with interleukin-6 levels was found. In COPD patients, they noted overall dampening of metabolite levels including energy-associated metabolic pathways such as creatine metabolism. Compared with smokers without COPD, these individuals had higher histamine levels and percent basophils. In this study, COPD was found to be related to changes in the serum metabolome, including a disruption in the histidine-histamine and creatine metabolic pathways. To know the pathogenic mechanisms implicated in COPD, the use of metabolomics was supported.