Effects of Carvacrol on Cognitive Function and Apoptotic Gene Expression in Trimethyltin- Induced Hippocampal Injury in Rats.

Abstract

Trimethyltin (TMT) chloride is an organotin compound used in industry. It has been linked to generating reactive oxygen species (ROS), inflammatory processes, and neuronal death. Carvacrol is a monoterpene phenol found in the Lamiaceae plant family, modulating inflammatory conditions and necroptosis in neural tissue. This study aimed to investigate the neuroprotective effects of carvacrol in a rat model of hippocampal neuronal injury induced by TMT. In this experimental study, sixty male Wistar rats were randomly divided into five groups (n=12): group 1 receiving saline, group 2 received dimethyl sulfoxide (DMSO) as a vehicle for 21 days, group 3 receiving a single dose of TMT (8 mg/kg) and groups 4 and 5 receiving carvacrol 40 and 70 mg/kg daily for 21 days after a single dose of TMT. All injections were intraperitoneal (I.P.). Caspase-3, Bax, Bcl-2, and Bdnf gene expression and the number of pyknotic neurons in the hippocampus were quantified. Spatial memory was assessed with a radial arm maze. Statistical analysis of histological data revealed the carvacrol significantly attenuated cognitive dysfunction and the number of pyknotic neurons in the hippocampal CA1 region of rats treated with TMT. Based on real-time polymerase chain reaction (PCR), carvacrol modulated the expression of genes involved in apoptosis (Bax and Caspase-3) and upregulated anti-apoptotic (Bcl-2) and brain derived neurotrophic factor (Bdnf) genes in the hippocampal tissue. These findings revealed neuroprotective effects of carvacrol which might be mediated by apoptotic and anti-apopetotic factors.