Neuroprotective Effects of Thymoquinone on the Hippocampus in a Rat Model of Traumatic Brain Injury.
World Neurosurg. 2015 Sep 30. Epub 2015 Sep 30. PMID: 26428323
BACKGROUND: Traumatic brain injury is a leading cause of morbidity and mortality worldwide. We evaluated the neuroprotective effects of thymoquinone (TQ) in a rat model of traumatic brain injury by using biochemical and histopathologic methods for the first time.
MATERIALS AND METHODS: Twenty-four rats were divided into sham (n = 8), trauma (n = 8), and TQ-treated (n = 8) groups. A moderate degree of head trauma was induced with the use of Feeney's falling weight technique, and TQ (5 mg/kg/day) was administered to the TQ-treated group for 7 days. All animals were killed after cardiac perfusion. Brain tissues were extracted immediately after perfusion without damaging the tissues. Biochemical procedures were performed with the serum, and a histopathologic evaluation was performed on the brain tissues. Biochemical experiments included malondialdehyde (MDA), reduced and oxidized coenzyme Q10 analysis, DNA isolationand hydroylazation, and glutathione peroxidase, and superoxide dismutase analyses.
RESULTS: Neuron density in contralateral hippocampal regions (CA1, CA2-3, and CA4) 7 days after the trauma decreased significantly in the trauma and TQ-treated groups, compared with that in the control group. Neuron densities in contralateral hippocampal regions (CA1, CA2-3, and CA4) were greater in the TQ-treated group than in the trauma group. TQ did not increase superoxide dismutase or glutathione peroxidase antioxidant levels. However, TQ decreased the MDA levels.
CONCLUSIONS: These results indicate that TQ has a healing effect on neural cells after head injury and this effect is mediated by decreasing MDA levels in the nuclei and mitochondrial membrane of neurons.