Nicotine and Cytisine Embryotoxicity in the Experimental Zebrafish Model

Tobacco smoking is one of the most serious health problems. Potentially lethal effects of nicotine for adults can occur with as little as 30 to 60 mg, although severe symptoms can arise with lower doses. Furthermore, the route of administration also influences the toxicity. Cytisine is one of the most popular medications in nicotinism treatment. Like nicotine, cytisine is a plant alkaloid, signaling through nicotinic acetylcholine receptors. Our study evaluated the effects of cytisine in nicotine-induced embryotoxic effects using zebrafish larvae. We examined the teratogenicity of nicotine and cytisine alone or in combination. Nicotine increased mortality and delayed hatching of zebrafish larvae in a dose-dependent manner. Cytisine did not affect mortality in a wide range of concentrations, and hatching delay was observed only at the highest concentrations, above 2 mM. Administering compounds together partially reduced the adverse teratogenic effect induced by nicotine alone. The protective effect of cytisine against the nicotine effect, observed in zebrafish, will contribute to future studies or treatments related to nicotine addiction or prenatal nicotine exposure in humans.

Automated summary

Tobacco smoking poses a serious health problem, as even small doses of nicotine can have potentially lethal effects on adults. The administration method of nicotine also affects its toxicity. Cytisine, a popular medication for nicotine addiction treatment, was evaluated in this study for its effects on nicotine-induced embryotoxicity using zebrafish larvae. Nicotine increased mortality and delayed hatching of zebrafish larvae, while cytisine did not affect mortality and only caused hatching delay at high concentrations. The combination of the two compounds partially reduced the adverse teratogenic effect of nicotine. This study provides insights for future research or treatments related to nicotine addiction or prenatal nicotine exposure.