title: Mechanisms of Cigarette Smoke Effects on Human Airway Smooth Muscle.
abstract: Cigarette smoke contributes to or exacerbates airway diseases such as asthma and COPD, where airway hyperresponsiveness and airway smooth muscle (ASM) proliferation are key features. While factors such as inflammation contribute to asthma in part by enhancing agonist-induced intracellular Ca(2+) ([Ca(2+)]i) responses of ASM, the mechanisms by which cigarette smoke affect ASM are still under investigation. In the present study, we tested the hypothesis that cigarette smoke enhances the expression and function of Ca(2+) regulatory proteins leading to increased store operated Ca(2+) entry (SOCE) and cell proliferation. Using isolated human ASM (hASM) cells, incubated in the presence and absence cigarette smoke extract (CSE) we determined ([Ca(2+)]i) responses and expression of relevant proteins as well as ASM proliferation, reactive oxidant species (ROS) and cytokine generation. CSE enhanced [Ca(2+)]i responses to agonist and SOCE: effects mediated by increased expression of TRPC3, CD38, STIM1, and/or Orai1, evident by attenuation of CSE effects when siRNAs against these proteins were used, particularly Orai1. CSE also increased hASM ROS generation and cytokine secretion. In addition, we found in the airways of patients with long-term smoking history, TRPC3 and CD38 expression were significantly increased compared to life-long never-smokers, supporting the role of these proteins in smoking effects. Finally, CSE enhanced hASM proliferation, an effect confirmed by upregulation of PCNA and Cyclin E. These results support a critical role for Ca(2+) regulatory proteins and enhanced SOCE to alter airway structure and function in smoking-related airway disease.
authors.affiliation: Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America; Department of Pediatrics, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Wylam
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America; Department of Physiology & Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Venkatachalem
authors.initials: V
authors.lastname: Sathish
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Sarah Kay
authors.initials: SK
authors.lastname: VanOosten
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Michelle
authors.initials: M
authors.lastname: Freeman
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: David
authors.initials: D
authors.lastname: Burkholder
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Thompson
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America; Department of Physiology & Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Pabelick
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America; Department of Physiology & Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America.
authors.forename: Y S
authors.initials: YS
authors.lastname: Prakash
mesh_terms: D051997:ADP-ribosyl Cyclase 1 / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers; D001980:Bronchi / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D049109:Cell Proliferation; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D009130:Muscle, Smooth / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D012137:Respiratory System / Q000378:metabolism*; D012907:Smoking / Q000009:adverse effects*; D050052:TRPC Cation Channels / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015415:Biomarkers; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; D014409:Tumor Necrosis Factor-alpha; D051997:ADP-ribosyl Cyclase 1; D002118:Calcium