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Effects of Nicotine on Proliferation and Survival in Human Umbilical Cord Mesenchymal Stem Cells

Cigarette smoking is known to have negative effects on tissue repair and healing. The aim of this study is to investigate the effects of nicotine in human umbilical cord mesenchymal stem cells (MSCs). After nicotine treatment, MSCs became pyknotic, vacuoles appeared in the cytoplasm and nucleus, and the nuclear boundary became fuzzy as observed using atomic force microscopy. Cell proliferation was inhibited in a dose‐dependent manner (P < 0.05 for all concentrations). The proportion of apoptotic MSCs was significantly increased in a dose‐dependent manner. The mitochondrial membrane potential was significantly decreased (P < 0.05). Nicotine‐treated MSCs had a significantly higher G0/G1 ratio (P < 0.05). Peptide mass fingerprinting identified 27 proteins that were differentially expressed between MSCs with and without nicotine treatment. These nicotine exerted toxic effects on MSCs are likely related, at least in part, to the altered expression of multiple proteins that are essential to the health and proliferation of these cells.