title: Functional Effects of Cigarette Smoke-Induced Changes in Airway Smooth Muscle Mitochondrial Morphology.
abstract: Long-term exposure to cigarette smoke (CS) triggers airway hyperreactivity and remodeling, effects that involve airway smooth muscle (ASM). We previously showed that CS destabilizes the networked morphology of mitochondria in human ASM by regulating the expression of mitochondrial fission and fusion proteins via multiple signaling mechanisms. Emerging data link regulation of mitochondrial morphology to cellular structure and function. We hypothesized that CS-induced changes in ASM mitochondrial morphology detrimentally affect mitochondrial function, leading to CS effects on contractility and remodeling. Here, ASM cells were exposed to 1% cigarette smoke extract (CSE) for 48 h to alter mitochondrial fission/fusion, or by inhibiting the fission protein Drp1 or the fusion protein Mfn2. Mitochondrial function was assessed via changes in bioenergetics or altered rates of proliferation and apoptosis. Our results indicate that both exposure to CS and inhibition of mitochondrial fission/fusion proteins affect mitochondrial function (i.e., energy metabolism, proliferation, and apoptosis) in ASM cells. In vivo, the airways in mice chronically exposed to CS are thickened and fibrotic, and the expression of proteins involved in mitochondrial function is dramatically altered in the ASM of these mice. We conclude that CS-induced changes in mitochondrial morphology (fission/fusion balance) correlate with mitochondrial function, and thus may control ASM proliferation, which plays a central role in airway health. J. Cell. Physiol. 232: 1053-1068, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Bharathi
authors.initials: B
authors.lastname: Aravamudan
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Michael
authors.initials: M
authors.lastname: Thompson
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota.|Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Gary C
authors.initials: GC
authors.lastname: Sieck
authors.affiliation: Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Robert
authors.initials: R
authors.lastname: Vassallo
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota.|Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Pabelick
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota.|Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota.
authors.forename: Y S
authors.initials: YS
authors.lastname: Prakash
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000818:Animals; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D049109:Cell Proliferation; D004734:Energy Metabolism; D005786:Gene Expression Regulation; D006019:Glycolysis; D006801:Humans; D008168:Lung / Q000473:pathology*; D053078:Membrane Potential, Mitochondrial; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D001678:Organelle Biogenesis; D012907:Smoking
chemical_list: D015415:Biomarkers; D000255:Adenosine Triphosphate