Department of Physiology, Institute for Biological Research "Siniša Stanković", National Institute of the Republic of Serbia, University of Belgrade, Bulevar despota Stefana 142, 11060, Belgrade, Serbia.
Faculty of Biology, Institute of Zoology, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia; Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE, Leiden, the Netherlands; Naturalis Biodiversity Center, Darwinweg 2, 2333 CR, Leiden, the Netherlands.
J Therm Biol. 2023 Feb;112:103474. doi: 10.1016/j.jtherbio.2023.103474. Epub 2023 Jan 10.
Ectotherms are particularly sensitive to global warming due to their limited capacity to thermoregulate, which can impact their performance and fitness. From a physiological standpoint, higher temperatures often enhance biological processes that can induce the production of reactive oxygen species and result in a state of cellular oxidative stress. Temperature alters interspecific interactions, including species hybridization. Hybridization under different thermal conditions could amplify parental (genetic) incompatibilities, thus affecting a hybrid's development and distribution. Understanding the impact of global warming on the physiology of hybrids and particularly their oxidative status could help in predicting future scenarios in ecosystems and in hybrids. In the present study, we investigated the effect of water temperature on the development, growth and oxidative stress of two crested newt species and their reciprocal hybrids. Larvae of Triturus macedonicus and T. ivanbureschi, and their T. macedonicus-mothered and T. ivanbureschi-mothered hybrids were exposed for 30 days to temperatures of 19°C and 24°C. Under the higher temperature, the hybrids experienced increases in both growth and developmental rates, while parental species exhibited accelerated growth (T. macedonicus) or development (T. ivanbureschi). Warm conditions also had different effects on the oxidative status of hybrid and parental species. Parental species had enhanced antioxidant responses (catalase, glutathione peroxidase, glutathione S-transferase and SH groups), which allowed them to alleviate temperature-induced stress (revealed by the absence of oxidative damage). However, warming induced an antioxidant response in the hybrids, including oxidative damage in the form of lipid peroxidation. These findings point to a greater disruption of redox regulation and metabolic machinery in hybrid newts, which can be interpreted as the cost of hybridization that is likely linked to parental incompatibilities expressed under a higher temperature. Our study aims to improve mechanistic understanding of the resilience and distribution of hybrid species that cope with climate-driven changes.
变温动物由于其体温调节能力有限，对全球变暖特别敏感，这可能会影响它们的表现和适应性。从生理学角度来看，较高的温度通常会增强生物过程，导致活性氧的产生，并导致细胞氧化应激状态。温度改变了种间相互作用，包括物种杂交。在不同的热条件下杂交可能会放大亲本（遗传）不兼容性，从而影响杂种的发育和分布。了解全球变暖对杂种生理的影响，特别是它们的氧化状态，有助于预测生态系统和杂种未来的情景。在本研究中，我们研究了水温对两种有角蝾螈及其相互杂交种的发育、生长和氧化应激的影响。将马氏蝾螈和伊氏蝾螈的幼虫以及它们的马氏蝾螈-母本和伊氏蝾螈-母本杂交种暴露在 19°C 和 24°C 的温度下 30 天。在较高温度下，杂种的生长和发育速度都有所增加，而亲代物种则表现出加速生长（马氏蝾螈）或发育（伊氏蝾螈）。温暖的条件也对杂种和亲代物种的氧化状态产生了不同的影响。亲代物种增强了抗氧化反应（过氧化氢酶、谷胱甘肽过氧化物酶、谷胱甘肽 S-转移酶和 SH 基团），使它们能够缓解温度诱导的应激（通过没有氧化损伤来揭示）。然而，升温诱导了杂种的抗氧化反应，包括以脂质过氧化形式出现的氧化损伤。这些发现表明，杂交蝾螈的氧化还原调节和代谢机制受到更大的破坏，这可以解释为与高温下表达的亲本不兼容性相关的杂交成本。我们的研究旨在提高对应对气候驱动变化的杂交种弹性和分布的机制理解。
