Loughland 2022 J Exp Biol
Loughland I, Lau GY, Jolly J, Seebacher F (2022) Rates of warming impact oxidative stress in zebrafish (Danio rerio). |
Β» J Exp Biol 225:jeb243740. PMID: 35179603
Loughland Isabella, Lau Gigi Y, Jolly Jordan, Seebacher Frank (2022) J Exp Biol
Abstract: Potentially negative effects of thermal variation on physiological functions may be modulated by compensatory responses, but their efficacy depends on the time scale of phenotypic adjustment relative to the rate of temperature change. Increasing temperatures in particular can affect mitochondrial bioenergetics and rates of reactive oxygen species (ROS) production. Our aim was to test whether different rates of temperature increase affect mitochondrial bioenergetics and modulate oxidative stress. We exposed zebrafish (Danio rerio) to warming from 20Β°C to 28Β°C over 3, 6, 24 or 48 h, and compared these with a control group that was kept at constant 20Β°C. Fish exposed to the fastest (3 h) and slowest (48 h) rates of warming had significantly higher rates of H2O2 production relative to the control treatment, and the proportion of O2 converted to H2O2 (H2O2/O2 ratio) was significantly greater in these groups. However, ROS production was not paralleled by differences in mitochondrial substrate oxidation rates, leak respiration rates or coupling (respiratory control ratios). Increased rates of ROS production did not lead to damage of proteins or membranes, which may be explained by a moderate increase in catalase activity at the fastest, but not the slowest, rate of warming. The increase in ROS production at the slowest rate of warming indicates that even seemingly benign environments may be stressful. Understanding how animals respond to different rates of temperature change is important, because the rate determines the time period for phenotypic adjustments and it also alters the environmental thermal signal that triggers compensatory pathways. β’ Keywords: Catalase, Mitochondria, Oxidative damage, Reactive oxygen species, Respiratory control ratio, Temperature β’ Bioblast editor: Plangger M β’ O2k-Network Lab: CA Vancouver Richards JG
Labels: MiParea: Respiration
Stress:Oxidative stress;RONS Organism: Zebrafish Tissue;cell: Skeletal muscle Preparation: Isolated mitochondria
Regulation: Temperature Coupling state: LEAK, OXPHOS, ET Pathway: N, NS HRR: Oxygraph-2k, O2k-Fluorometer
2022-12, AmR