Nicotine exposure during differentiation causes inhibition of N-myc expression

Abstract

BackgroundThe ability of chemicals to disrupt neonatal development can be studied using embryonic stem cells (ESC). One such chemical is nicotine. Prenatal nicotine exposure is known to affect postnatal lung function, although the mechanisms by which it has this effect are not clear. Since fibroblasts are a critical component of the developing lung, providing structure and secreting paracrine factors that are essential to epithelialization, this study focuses on the differentiation of ESC into fibroblasts using a directed differentiation protocol.MethodsFibroblasts obtained from non-human primate ESC (nhpESC) differentiation were analyzed by immunohistochemistry, immunostaining, Affymetrix gene expression array, qPCR, and immunoblotting.ResultsResults of these analyses demonstrated that although nhpESCs differentiate into fibroblasts in the presence of nicotine and appear normal by some measures, including H&E and SMA staining, they have an altered gene expression profile. Network analysis of expression changes demonstrated an over-representation of cell-cycle related genes with downregulation of N-myc as a central regulator in the pathway. Further investigation demonstrated that cells differentiated in the presence of nicotine had decreased N-myc mRNA and protein expression and longer doubling times, a biological effect consistent with downregulation of N-myc.ConclusionsThis study is the first to use primate ESC to demonstrate that nicotine can affect cellular differentiation from pluripotency into fibroblasts, and in particular, mediate N-myc expression in differentiating ESCs. Given the crucial role of fibroblasts throughout the body, this has important implications for the effect of cigarette smoke exposure on human development not only in the lung, but in organogenesis in general.

Electronic Cigarette Smoke Impairs Normal Mesenchymal Stem Cell Differentiation

“…Our results suggest that smoke extracts might be inhibiting the cytoplasmic exchange of survival and differentiation signals, by down-regulating Cx43 expression in MSCs. In addition to the fact that nicotine might be a player in the impairment of differentiation 69 , smoke contains other ingredients that are toxic and could impair differentiation as well 70 , 71 . Subsequently, tissue repair might be compromised upon exposure to both cigarette and e-cigarette.…”

Impact of Tobacco Smoke and Nicotine Exposure on Lung Development

“…3,28 In animal models, tobacco smoke and nicotine exposure during in utero or early postnatal life has been shown to alter expression of genes involved in cell proliferation, T-helper (Th) type 1 (Th1) and type 2 (Th2) immune balance, fibrosis, and viral immune responses (Table 1). [29][30][31][32][33] Nicotine Exposure and Lung Development Nicotinic acetylcholine receptors (nAChRs) are ligandgated ion channels that enable flow of cations through the channel when bound by acetylcholine and other nAChR agonists, including nicotine. These receptors consist of five transmembrane subunits that form a central ion pore.…”

“…36,37 The effects of nicotine may occur very early in lung development. For example, Ben-Yehudah and colleagues 29 have shown that nonhuman primate embryonic stem cells express nAChRs. In their study, exposure of nicotine caused downregulation of n-Myc expression and differentiation of nonhuman primate embryonic stem cells into fibroblasts, demonstrating that exposure to nicotine during embryogenesis can affect embryonic stem cell differentiation.…”

Tobacco Smoking During Pregnancy Is Associated With Increased Risk of Moderate/Severe Bronchopulmonary Dysplasia: A Systematic Review and Meta-Analysis

“…There is strong evidence from animal studies on the adverse impact of antenatal smoke exposure on lung development (10,11). The effects of nicotine may occur very early, affecting embryonic stem cell differentiation (66). Intrauterine smoke exposure disrupts lung development in mice, resulting in a pathological picture similar to BPD (67).…”