Pereira Tatiana M, Minari Marina, Carvajalino-Fernández Juan Manuel, Moreira Daniel C, Hermes-Lima Marcelo
Departamento de Biologia Celular, Universidade de Brasília, Brasilia 70910-900, Brazil.
Departamento de Biología, Universidad Nacional de Colombia, Bogotá 111321, Colombia.
Animals (Basel). 2025 Apr 29;15(9):1251. doi: 10.3390/ani15091251.
Intertidal organisms experience daily environmental fluctuations, including changes in temperature, UV radiation, and aerial exposure during low tide, requiring physiological strategies for survival. One adaptation is the "preparation for oxidative stress" (POS), where antioxidants are upregulated preemptively to mitigate oxidative damage. While POS has been documented in over 120 species, in the case of intertidal species, most studies focus on single stressors under controlled-laboratory conditions. This study investigated POS in the sea urchin under natural multi-stress conditions. Sampling occurred over a single day (from 5 a.m. to noon), analyzing three conditions: submerged (S), aerially exposed for 2 h (AE), and reimmersed for 2 h (R). There was a ~4 °C temperature increase in the AE group compared to the S group, with a peak of solar radiation during reoxygenation. Antioxidant enzyme activity-catalase, glutathione transferase (GST), and superoxide dismutase (SOD)-and lipid peroxidation (TBARS) were assessed in gonad and intestine tissues. GST activity increased by fourfold in the intestines of AE individuals, while TBARS was elevated in gonads, where no antioxidant upregulation happened. These results suggest that the POS-response (increase in GST) was triggered by the interaction of temperature and aerial exposure. This research emphasizes the critical importance of field studies in understanding complex, natural multi-stressor environments.
潮间带生物每天都要经历环境波动，包括温度变化、紫外线辐射以及退潮时的空气暴露，这就需要有生存的生理策略。一种适应方式是“氧化应激预适应”（POS），即抗氧化剂被预先上调以减轻氧化损伤。虽然在120多种物种中都有POS的记录，但对于潮间带物种而言，大多数研究集中在实验室控制条件下的单一应激源。本研究调查了自然多应激条件下海胆的POS。在一天内（从凌晨5点到中午）进行采样，分析三种情况：淹没状态（S）、空气暴露2小时（AE）和重新浸没2小时（R）。与S组相比，AE组温度升高了约4°C，在复氧期间太阳辐射达到峰值。对性腺和肠道组织中的抗氧化酶活性——过氧化氢酶、谷胱甘肽转移酶（GST）和超氧化物歧化酶（SOD）——以及脂质过氧化（TBARS）进行了评估。AE个体肠道中的GST活性增加了四倍，而性腺中的TBARS升高，性腺中没有抗氧化剂上调现象。这些结果表明，POS反应（GST增加）是由温度和空气暴露的相互作用触发的。本研究强调了实地研究在理解复杂的自然多应激环境中的至关重要性。
