Background: Thymol (THY), which is a monocyclic monoterpene, found in oil of thyme
various other kinds of plants. Until today, although different biological properties of THY have been
indicated, its neurological toxicity has never been investigated.
Method: In this study, in vitro
antiproliferative (by 3-(4,5 dimetylthiazol-2-yl)-2,5 diphenlytetrazolium
bromide (MTT) test), genotoxic (by single cell gel electrophoresis (SCGE)) and oxidative effects
(by total antioxidant capacity (TAC) and total oxidative status (TOS) analysis) of THY (0-400
mg/L) were assessed on cultured primary rat neurons (CPRNs) and N2a neuroblastoma cells.
Results: The obtained data from MTT analysis revealed that THY (only at 400 mg/L) led to significant
(p<0.05) decreases of the cell viability in cultured primary rat neurons. And, THY was found to
inhibit cell growth in N2a cells at concentrations of 200 and 400 mg/L. Again, DNA damage rates
were statistically indifferent (p>0.05) in both treated cell type as compared to control group. The present
results also showed that 10, 25 and 50 mg/L of THY application into the cell cultures supported
antioxidant capacity in primary rat neurons but not in N2a cells.
Conclusion: In a conclusion, these results confirm that THY may have antiproliferative potential
against brain tumor cells involving oxidative alteration.