Oxidative stress and HIF-1 DNA binding during stressful cold exposure and recovery in the North Sea eelpout (Zoarces viviparus)

Effects of acute cold exposure (at 1 °C and 5 °C) on tissue redox state and oxidative stress parameters, as well as the onset of hypoxic signaling were investigated in the North Sea eelpout, Zoarces viviparus. Activation of the transcription factor HIF-1 (hypoxia inducible factor) was detected in liver samples after acute cold exposure. At this temperature the cellular redox milieu was significantly reduced (below − 270 mV) as compared to controls (− 250 to − 267 mV). Increased levels of oxidative stress parameters (TBARS and protein carbonyls) were observed mainly during recovery at control temperature (12 °C). This increase in oxidative stress parameters, in spite of maintained antioxidant capacity, indicates that acute cold stress and recovery mimic ischemia/reperfusion events as found in mammals. Notably the non-enzymatic antioxidant defense (e.g. glutathione) may play an important role for eelpout ROS scavenging capacity under cold stress.