Paracrine potential of fibroblasts exposed to cigarette smoke extract with vascular growth factor induction

Abstract

Objectives/Hypothesis Nicotine, a major constituent of cigarette smoke, can activate the cholinergic anti-inflammatory pathway by binding to α7-nicotinic acetylcholine receptor (α7nAChR) expressed on the surface of certain cells. Here, we ask whether cigarette smoke extract induced different paracrine factors compared to the in vivo regulator of inflammation, tumor necrosis factor-α, in human vocal fold fibroblasts (hVFFs) shown to express low levels of α7nAChR. Study Design In vitro. Methods α7nAChR was detected by nested polymerase chain reaction and immunohistochemistry. γH2AX, a marker for DNA double-stand breaks, was measured by immunofluorescence. Cigarette smoke extract was prepared in accordance with investigators studying effects of cigarette smoke. hVFFs treated for 3 hours had media replaced for an additional 24 hours. Cytokine, chemokine, and growth factor levels in media were assessed by multiplex analysis. Results α7nAChR expression levels decreased with the passage number of fibroblasts. Tumor necrosis factor-α induced a significantly different profile of cytokines, chemokines, and growth factor compared to cigarette smoke extract exposure. Cigarette smoke extract at a concentration not associated with induction of γH2AX nuclear foci significantly increased vascular endothelial growth factor. Conclusions Cigarette smoke extract elicited a response important for regulation of angiogenesis and vascular permeability during inflammation, without evidence of DNA double-stand breaks associated with carcinogenesis. hVFFs are capable of participating in paracrine regulation of pathological blood vessel formation associated with cigarette smoking–related diseases (ie, Reinke edema). These cells express α7nAChR, an essential component of the cholinergic anti-inflammatory pathway regulated by the vagus nerve in certain tissues and a target of therapeutic agents.

Acute exposure to vibration is an apoptosis‐inducing stimulus in the vocal fold epithelium

“…Increased concentrations of TNF-α administered to cultured human vocal fold fibroblasts have been found to inhibit the rate of cell proliferation after 9 days (18). In contrast, Berchtold et al (17) observed no evidence of cell death after 24 hours following TNF-α administration to cultured human vocal fold fibroblasts. It remains unknown whether TNF-α initiates apoptosis or whether apoptosis leads to alterations in TNF-α.…”

“…In addition, there is evidence of tumor necrosis factor-alpha (TNF-α) upregulation in response to biomechanical trauma in the vocal folds (15, 16). However, studies reveal inconsistencies regarding the effect of TNF-α on cell death in the vocal folds (17, 18). To examine the relationship between TNF-α and apoptosis, a secondary purpose of this study was to determine whether gene transcript and protein levels of TNF-α are upregulated with increasing durations of vibration exposure.…”

Management of Laryngeal Airway in Reinke's Edema: An Anesthetic Overview

“…5 Nicotine components of smoking stimulate angiogenesis, causing increased vascular permeability and therefore, forming subepithelial edema. 6 Kajek credited for RE with identification of edema at subepithelial compartment of vocal fold, which is superficial to vocal ligament, anteriorly bounded by Broyle's ligament and posteriorly by vocal process of the arytenoids. 7 Hirano has identified the subepithelial compartment of vocal fold as superficial lamina propria.…”

CD34‐positive fibroblasts in Reinke's edema

“…Thus, it has also been observed that cigarette smoke condensate increases intracellular reactive oxygen species, as well as heme oxigenase 1 and SOD1 gene expression in VFFs . Furthermore, VFFs are capable of participating in paracrine regulation of pathological blood vessel formation in cigarette smoking‐related Reinke's edema (cigarette smoke extract increases vascular endothelial growth factor) …”