title: Living in flowing water increases resistance to ultraviolet B radiation.
abstract: Ultraviolet B radiation (UV-B) is an important environmental driver that can affect locomotor performance negatively by inducing production of reactive oxygen species (ROS). Prolonged regular exercise increases antioxidant activities, which may alleviate the negative effects of UV-B-induced ROS. Animals naturally performing exercise, such as humans performing regular exercise or fish living in flowing water, may therefore be more resilient to the negative effects of UV-B. We tested this hypothesis in a fully factorial experiment, where we exposed mosquitofish (Gambusia holbrooki) to UV-B and control (no UV-B) conditions in flowing and still water. We show that fish exposed to UV-B and kept in flowing water had increased sustained swimming performance (Ucrit), increased antioxidant defences (catalase activity and glutathione concentrations) and reduced cellular damage (lipid peroxidation and protein carbonyl concentrations) compared with fish in still water. There was no effect of UV-B or water flow on resting or maximal rates of oxygen consumption. Our results show that environmental water flow can alleviate the negative effects of UV-B-induced ROS by increasing defence mechanisms. The resultant reduction in ROS-induced damage may contribute to maintain locomotor performance. Hence, the benefits of regular exercise are 'transferred' to improve resilience to the negative impacts of UV-B. Ecologically, the mechanistic link between responses to different habitat characteristics can determine the success of animals. These dynamics have important ecological connotations when river or stream flow changes as a result of weather patterns, climate or human modifications.
authors.affiliation: School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia.
authors.forename: Ensiyeh
authors.initials: E
authors.lastname: Ghanizadeh-Kazerouni
authors.affiliation: School of Biological Sciences, University of Queensland, St Lucia, QLD 4072, Australia.
authors.forename: Craig E
authors.initials: CE
authors.lastname: Franklin
authors.affiliation: School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia frank.seebacher@sydney.edu.au.
authors.forename: Frank
authors.identifier: 0000-0002-2281-9311
authors.initials: F
authors.lastname: Seebacher
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001481:Basal Metabolism / Q000528:radiation effects; D002374:Catalase / Q000378:metabolism; D003532:Cyprinodontiformes / Q000502:physiology*; D017753:Ecosystem; D029941:Fish Proteins / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000528:radiation effects; D008297:Male; D018384:Oxidative Stress / Q000528:radiation effects*; D010101:Oxygen Consumption / Q000528:radiation effects; D065840:Protective Factors; D050050:Protein Carbonylation / Q000528:radiation effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013550:Swimming; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000975:Antioxidants; D029941:Fish Proteins; D017382:Reactive Oxygen Species; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione
keywords: Antioxidants; Exercise; Habitat modification; Locomotion; Reactive oxygen species