Comparative cytotoxicity study of nicotine and cotinine on MRC-5 cell line

Introduction:
This text is a summary of a research article that examines the comparative cytotoxicity of nicotine and its metabolite, cotinine, on the MRC-5 lung fibroblasts. The study aims to assess the effects of various concentrations of nicotine and cotinine on the cell viability of the MRC-5 cells.

Key Points:

* The study used the MTT assay to determine the cell viability of the MRC-5 cells treated with nicotine and cotinine.
* high concentrations (2mM) of both nicotine and cotinine decreased the viability of MRC-5 cells.
* Nicotine proved to be more cytotoxic than cotinine.
* Unlike nicotine, the proliferative capacity of MRC-5 cells is maintained after 48 hours of cotinine treatment.
* at concentrations similar to the levels observed in the plasma of smokers, nicotine and cotinine were not cytotoxic on MRC-5 cell line.
* Nicotine exerts dose- and time-dependent cytotoxic effects on the mesenchymal stem cells derived from human periodontium.
* Nicotine and cigarettes extract were demonstrated to induce cytotoxicity in human embryonic lung fibroblast, MRC-9.
* The present study investigated the in vitro effects of nicotine and cotinine on proliferation of MRC-5 cell line, a diploid human cell culture line composed of fibroblasts derived from normal lung tissue of a 14-week-old male fetus.

Main Message:
The study highlights the comparative cytotoxicity of nicotine and its metabolite, cotinine, on the MRC-5 lung fibroblasts. While both nicotine and cotinine exhibit cytotoxic effects at higher concentrations, nicotine is more cytotoxic than cotinine. Importantly, at concentrations similar to those observed in the plasma of smokers, nicotine and cotinine were not cytotoxic on MRC-5 cell line, indicating their safety in therapeutic uses. however, the study also highlights the potential cytotoxic effects of nicotine on other experimental systems, such as mesenchymal stem cells derived from human periodontium and human embryonic lung fibroblast, MRC-9. Therefore, further studies are needed to fully understand the toxicological profile of nicotine and cotinine, particularly in therapeutic settings.

Vlasceanu, ana-Maria, Daniela Baconi, Bianca Galateanu, Miriana Stan, and Cristian Balalau. “Comparative Cytotoxicity Study of Nicotine and Cotinine on MRC-5 Cell Line.” Journal of Mind and Medical Sciences 5, no. 1 (april 1, 2018): 117–22. https://doi.org/10.22543/7674.51.P117122.