Abstract

Objective criteria are essential in forensic toxicology for elucidating combustion-related deaths. Carbon monoxide (CO) and carbon dioxide (CO₂) impair oxygen delivery by competing with oxygen for hemoglobin binding and by disrupting cellular oxidative metabolism. This study aimed to evaluate biochemical changes in blood and brain tissues, neuroglobin gene expression in the brain, and histopathological alterations following CO and CO₂ exposure in rats, hypothesizing differential neuroglobin responses between the two gases. Twenty-four male Wistar albino rats (300 ± 50 g) were randomly divided into three groups and exposed to either carbon monoxide (0.05%), carbon dioxide (20%), or no gas (control) in a controlled glass isolation chamber. Blood and brain samples were collected for toxicological, genetic, and histopathological analyses. Blood gas analyses revealed intergroup differences in pH and bicarbonate levels, indicating altered oxidative balance. Antioxidant enzyme activity suggested increased oxidative stress in both exposure groups. Histopathological examination demonstrated more severe neuronal damage in the carbon monoxide-exposed group compared with the carbon dioxide and control groups. Neuroglobin expression levels showed intergroup variation but did not reach statistical significance. Both CO and CO₂ exposure induced oxidative stress-related changes, with carbon monoxide causing more pronounced neuronal injury. Although neuroglobin levels tended to increase following exposure, the differences were not statistically significant. Further experimental studies may enhance understanding of neuroglobin’s role in forensic toxicology.

Key words: Carbon monoxide poisoning, carbon dioxide poisoning, neuroglobin, genetic toxicology, forensic toxicology