The effects of a rapid transfer from a low (3 °C) to a warm (23 °C) temperature on oxidative stress markers and antioxidant defenses were studied in the brain, liver and kidney of the goldfish, Carassius auratus. Cold-acclimated fish were acutely moved to 23 °C and sampled after 1, 6, 12, 24, 48 or 120 h of warm temperature exposure. Lipid peroxide levels increased quickly during the first few hours at 23 °C, but thiobarbituric acid-reactive substances changed little. Protein carbonyl content was reduced by 20-40% in the liver over the entire experimental course, but increased transiently in the kidney. The content of high-molecular mass thiols decreased by two-thirds in the brain and was affected slightly in other organs. By contrast, total low-molecular mass thiols (e.g. glutathione and others) increased transiently. Activities of the primary antioxidant enzymes-superoxide dismutase and catalase-were generally unaffected in goldfish organs, whereas glutathione-dependent enzymes were elevated in the brain and kidney after 24-48 h at 23 °C. Glutathione peroxidase increased by 1.5-2.3-fold and glutathione-S-transferase by 1.7-fold. Hence, a short-term exposure to warm temperature disturbed several oxidative stress markers, but only slightly affected the activities of antioxidant enzymes. However, comparison of the current data for cold-acclimated winter fish with the same parameters in summer fish suggests that longer exposure to high ambient temperature requires the enhancement of activities of glutathione-dependent enzymes for maintaining the steady-state levels lipid peroxidation and protein oxidation in goldfish tissues.

Antioxidant enzymes, Goldfish, Lipid peroxidation, Oxidative stress, Temperature adaptation
Journal of Thermal Biology
Department of Biology

Bagnyukova, T.V., Lushchak, O.V., Storey, K, & Lushchak, V.I. (2007). Oxidative stress and antioxidant defense responses by goldfish tissues to acute change of temperature from 3 to 23 °C. Journal of Thermal Biology, 32(4), 227–234. doi:10.1016/j.jtherbio.2007.01.004