Efectos de las condiciones de almacenamiento en biomarcadores de estrés oxidativo: implicaciones metodológicas para...

Understanding oxidative stress in ecological and evolutionary contexts requires reliable biomarker quantification across taxa, tissues, and experimental setups. However, storage conditions such as temperature and duration may bias these measurements. Here, we evaluated the stability of oxidative stress biomarkers, including three antioxidant enzymes (superoxide dismutase, glutathione reductase, glutathione peroxidase) and a lipid peroxidation marker (malondialdehyde) in amphibian, mammal, bird, and insect samples stored under various temperature conditions (-80 °C, -20 °C, 4 °C) from hours to eight months. Storage significantly affected biomarker values depending on the marker, tissue, and taxon. Notably, even long-term storage at -80 °C altered some markers. In insect samples, lipid peroxidation was also influenced by triglyceride levels, indicating a potential confounding factor. Our results highlight the need to consider storage effects in oxidative stress studies. We also provide practical recommendations, aiming to improve data reliability across field and laboratory eco-evolutionary studies, as well as biomedical contexts.