Single-Cell RNA-Sequencing of Human Embryonic Stem Cell Differentiation Delineates Adverse Effects of Nicotine on Embryonic Development

Nicotine, the main constituent of tobacco, is highly detrimental to the developing fetus by increasing the risk of gestational complications and organ disorders. The effects of nicotine on human embryonic development and related mechanisms, however, remain largely unresolved. Here, we performed single-cell RNA-sequencing (scRNA-seq) of human embryonic stem cell (hESC)-derived embryoid body (EB) in the presence or absence of nicotine. Nicotine induced lineage-specific responses and dysregulated cell-to-cell communication in EBs, shedding light on the adverse effects of nicotine on human embryonic development. Additionally, nicotine reduced cell viability, increased reactive oxygen species (ROS), and altered cell cycling in EBs. Abnormal Ca2+ signaling was found in muscle cells upon nicotine exposure and verified in hESC-derived cardiomyocytes. Consequently, our scRNA-seq data suggests direct adverse effects of nicotine on hESC differentiation at the single-cell level and offers new method for evaluating drug and environmental toxicity on human embryonic development in utero.