Neurotrophic and Neurotoxic Effects of Retinoic Acid on Human Neural Stem Cell Culture.

Background: Retinoic acid (RA) is one of the most critical molecules in the organic development of human being; it has been implicated in controlling of hundreds of genes which control several processes in human development. Furthermore, RA has negative insult on pregnancy outcome since it has teratogenic potential when used in high doses. Materials and Methods: Human neural stem cells are used in this study to test the effect RA in different doses on cell viability, cellular protein amount, neurite length, neurosphere sizes, reactive oxygen species (ROS) production, and migration distance. Results and Conclusions: Our results show that RA at low doses (2, 5 µM) preserve cell stemness and increase the sizes of neurospheres significantly, but at high doses, it appears that RA has a neurotoxic effect on these stem cells through significant increase in ROS which has negative effects on neurite length and cellular migration. [ABSTRACT FROM AUTHOR]