bioRxiv · 10.1101/193003
Long-term cardiovascular re-programming by short-term perinatal exposure to nicotine‘s main metabolite cotinine
Abstract
BackgroundCotinine - a nicotine by-product and biomarker of passive perinatal tobacco smoke exposure - is historically considered to lack significant health effects. We challenged this notion and sought \"proof-of-concept\" evidence of the adverse developmental potential of exposure to this substance at real-life levels.\n\nMethodsPregnant C57 mice drank nicotine or cotinine-laced water for 6wks from conception (NPRE = 2% saccharin+100g nicotine/ml; CPRE = 2% saccharin + 10g cotinine/ml) or for 3wks after birth (CPOST = 2% saccharin + 30g cotinine/ml). Controls drank 2% saccharin (CTRL). At 17{+/-}1weeks male pups (CTRL n=6; CPOST n=6; CPRE n=8; NPRE n=9) were instrumented for EEG and blood pressure (BP) telemetry. We evaluated (i) cardiovascular control during sleep (at rest / during stress); (ii) arterial reactivity ex vivo; (iii) expression of genes involved in arterial constriction/dilation.\n\nResultsBlood cotinine levels (ELISA) recapitulated passive smoker mothers-infants. Pups exposed only to cotinine exhibited (i) mild bradycardia - hypotension at rest (p<0.001); (ii) attenuated (CPRE, p<0.0001) or reverse (CPOST; p<0.0001) BP reactivity to asphyxia; (iii) pronounced adrenergic hypo-contractility (p<0.0003), low Protein Kinase C (p<0.001) and elevated adrenergic receptor mRNA (p<0.05) (all drug-treated arteries). NPRE pups also exhibited endothelium-mediated dysfunction.\n\nConclusionsCotinine has subtle, enduring developmental consequences. Some cardiovascular effects of nicotine can plausibly arise via conversion to cotinine. Low-level exposure to this metabolite may pose unrecognized perinatal risks. Adults must avoid inadvertently exposing a fetus or infant to cotinine as well as nicotine.
Source connections
Explore related subjects
Keep this discovery
Bastianini, S., Lo Martire, V., Silvani, A., Zoccoli, G., Berteotti, C., Lagercrantz, H., Arner, A., Cohen, G.. 2017-09-23. Long-term cardiovascular re-programming by short-term perinatal exposure to nicotine‘s main metabolite cotinine. https://doi.org/10.1101/193003
Cite the original work for its findings. Save a collection to share your selection of sources.