Serum lipid peroxidation markers are correlated with those in brain samples in different stress models

Objective Stress can stimulate increased production of oxygen radicals. We investigated the correlations between serum levels of lipid peroxidation markers and those in brain samples in different stress models. Methods Animals (n = 96) were divided equally into eight groups: a control group and groups treated with vitamin E (Vit E); exposed to immobilisation stress; exposed to immobilisation stress and treated with Vit E; exposed to cold stress; exposed to cold stress and treated with Vit E; exposed to both immobilisation and cold stress; and a final group exposed to both immobilisation and cold stress and treated with Vit E. Thiobarbituric acid-reactive substance (TBARS) in brain samples and levels of TBARS, corticosterone, conjugated dienes (CD), lipids, and paraoxonase-1 (PON1) activity in serum were analysed. Results Serum corticosterone (p < 0.001), CD (p < 0.05), lipid (p < 0.05) levels, and brain TBARS (p < 0.05) levels were significantly higher in all stress groups than in controls, and the elevated levels were reversed in the Vit E-treated stress groups (p < 0.05). Serum PON1 activity was not different among the groups (p > 0.05). Serum TBARS levels increased significantly in all stress groups (p < 0.05), but this elevation was only reversed in the group exposed to both immobilisation and cold stress and treated with Vit E (p < 0.001). Conclusion These results suggest that serum levels of lipid peroxidation markers can be determined readily and may be useful as indicators to evaluate the effects of oxidative stress in the brain.