Introduction: Traumatic brain injuries (TBI) are a major cause of mortality and disability among young adults. TBI are characterized by primary injury, the result of a mechanical impact to the cranium and a secondary injury, a series of molecular mechanism processes developing thereafter. Cerebral cells modify their gene and protein expression as a result of the injury. Epigenetic modifications have a key role as regulators of gene transcription and may simultaneously be involved in the regulation of the molecular pathways following TBI. However, the mechanisms are unknown.
Objectives: To clarify whether modification in the expression of Histone Acetyl Transferase1 (HAT1) and Histone deacetylase2 (HDAC 2) occurs during secondary brain damage.
Methods: Rat diffused head injury model was used; 72 hours post injury animals were sacrificed and the brains were removed for immunohistochemistry staining with Caspase 3, HAT1 and HDAC2 antibodies. We compared these stains in the perilesional versus the contralateral cortex.
Results: An increase of Caspase 3 stained cells were observed in the perilesional cortex. HAT1 expression was elevated and HDAC2 expression reduced in the injured cortex.
Conclusions: TBI induced modifications in the expression of epigenetic factors were concomitant with increases in apoptotic cell death. The mitochondria involved in the apoptotic processes is a target for epigenetic regulation and also influences it at the same time.
Discussion: This study contributes to the understanding of epigenetic modification following TBI. Further study on the relationship between mitochondrial activity and epigenetic regulation has to be performed in order to develop novel drugs and therapies for TBI.