Protection with thymoquinone against formaldehyde-induced neurotoxicity in the rats.

Introduction: This study aimed to investigate the neurotoxic damage of formaldehyde (FA), which is commonly used in medicine and industrial fields, for the hippocampus of rats and the protective role of thymoquinone (TQ) against this neurotoxicity.

Methods: There were five groups with eight rats in each. Two control groups were formed, in one of them physiological saline was applied and in the other one corn oil was applied. FA was injected in Group 3. Group 4 was exposed to FA and TQ simultaneously. Group 5 received TQ only. At the end of the experiment animals were sacrificed and brain tissues were removed for biochemical and histopathological investigation.

Results: catalase (CAT), glutathione peroxidase (GSH-px) and superoxide dismutase (SOD), all known as enzymes with antioxidant activities, were increased in FA and TQ simultaneously administered group. FA caused prominent subarachnoidal hemorrhage and vacuolization. Vacuolization was not observed but occasional subarachnoidal hemorrhage was detected in the FA+TQ group.

Conclusion: Neurotoxic damage in hippocampus induced by FA was reverted by administration of TQ (Tab. 1, Fig. 1, Ref. 26).