Little Cigars are More Toxic than Cigarettes and Uniquely Change the Airway Gene and Protein Expression

Sci Rep. 2017 Apr 27:7:46239. doi: 10.1038/srep46239.

Abstract

Little cigars (LCs) are regulated differently than cigarettes, allowing them to be potentially targeted at youth/young adults. We exposed human bronchial epithelial cultures (HBECs) to air or whole tobacco smoke from cigarettes vs. LCs. Chronic smoke exposure increased the number of dead cells, lactate dehydrogenase release, and interleukin-8 (IL-8) secretion and decreased apical cilia, cystic fibrosis transmembrane conductance regulator (CFTR) protein levels, and transepithelial resistance. These adverse effects were significantly greater in LC-exposed HBECs than cigarette exposed cultures. LC-exposure also elicited unique gene expression changes and altered the proteomic profiles of airway apical secretions compared to cigarette-exposed HBECs. Gas chromatography-mass spectrometry (GC-MS) analysis indicated that LCs produced more chemicals than cigarettes, suggesting that the increased chemical load of LCs may be the cause of the greater toxicity. This is the first study of the biological effects of LCs on pulmonary epithelia and our observations strongly suggest that LCs pose a more severe danger to human health than cigarettes.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bronchi / metabolism*
  • Bronchi / pathology*
  • Cell Death / drug effects
  • Cell Line
  • Cigar Smoking / adverse effects*
  • Coal Tar
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / metabolism
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism
  • Epithelial Cells / pathology
  • Gene Expression Regulation / drug effects*
  • Humans
  • Inflammation / pathology
  • Mass Spectrometry
  • Nicotiana
  • Proteome / metabolism
  • Tobacco Products / toxicity*

Substances

  • CFTR protein, human
  • Proteome
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • Coal Tar