Tag Archives: superoxide radical
Cytochrome P450 dependent free radical processes in the liver microsomes of rats administered diethyl phthalate
О. V. Kеtsa*, М. М. Маrchenko
Educational and Scientific Institute of Biology, Chemistry and Natural Resources,
Yuriy Fedkovych Chernivtsi National University, Chernivtsi, Ukraine;
*e-mail: o.ketsa@chnu.edu.ua
Received: 28 May 2025; Revised: 03 July 2025;
Accepted: 12 September 2025; Available on-line: 17 September2025
Diethyl phthalate (DEP) is widely used as a plasticizer and aromatic additive in various consumer products. Biotransformation of this xenobiotic occurs through the cytochrome P450 (CYP) -hydroxylating system, the catalytic cycle of which is accompanied by ROS generation in uncoupling reactions. The present study investigated the effects of DEP administration on the CYP-dependent ROS generation and lipid peroxidation in the rat liver microsomes. The experiment was conducted on three groups of purebred white rats: control (intact animals); rats orally administered with DEP at a dose of 2.5 or 5.4 mg/kg b.w per day for 21 days. CYP-mediated ROS generation was initiated by adding 0.24 μmol/l NADPH to the incubation mixture. It was found that daily administration of DEP at a dose of 2.5 mg/kg led to an increase in the rate of O2•– formation, H2O2 content, and intensification of lipid peroxidation in the liver microsomes only on the 21st day of the experiment. In contrast, administration of DEP at a dose of 5.4 mg/kg resulted in increased content of primary, secondary and final lipid peroxidation products as early as on the 14th day of xenobiotic exposure, indicating a dose- and time-dependent effect of DEP on the oxidative stress intensity in liver microsomes.
Proteins oxidative modification and antioxidant enzymes activity in the liver mitochondria of rats under laser irradiation and administration of ω-3 polyunsaturated fatty acids
O. V. Ketsa*, M. O. Zelinska, M. M. Marchenko
Fedkovich Chernovtsy National University, Chernovtsy, Ukraine;
*e-mail: o.ketsa@chnu.edu.ua
Received: 12 August 2021; Accepted: 21 January 2022
The effect of laser irradiation of rats combined with omega-3 polyunsaturated fatty acids (ω-3 PUFA) administration on the proteins oxidative modification and superoxide dismutase and catalase activity in the mitochondrial fraction of the liver was investigated. Animals were irradiated with a 650 nm laser diode in the abdomen daily for 4 min at the distance of 10 cm from the skin surface. ω-3 PUFA were administered per os at a daily dose of 120 mg/kg of the body weight. Fatty acids in the fish oil were identified by gas chromatography. Animals were divided into five groups (12 animals in each group): I – intact rats (control); II – rats exposed to the daily laser irradiation for 7 or 14 days ; III – rats that received ω-3 PUFA two hours after irradiation; IV – rats that received ω-3 PUFA two hours before irradiation; V – rats that received ω-3 PUFA for 7 days before irradiation. The mitochondrial fraction of rat liver was obtained by differential centrifugation. The increase in the content of protein carbonyl derivatives and a decrease of protein thiol groups in the liver mitochondrial fraction were detected after seven-day laser irradiation of rats. As the duration of irradiation increases, superoxide dismutase and catalase activity was decreased, indicating a depletion of mitochondrial antioxidant reserves. No antioxidant effect was observed when ω-3 PUFA were administrated after laser irradiation and a slight antioxidant effect was shown when ω-3 PUFA were administrated two hours before irradiation. Preliminary seven-day administration ω-3 PUFA before laser irradiation was the most effective, as it reduced the level of protein carbonyl derivatives and O2•--generation, increased proteins SH-groups content and antioxidant enzymes activity.