Meta-analysis indicates that oxidative stress is both a constraint on and a cost of growth

Oxidative stress (OS) as a proximate mechanism for life-history trade-offs is widespread in the literature. One such resource allocation trade-off involves growth rate, and theory suggests that OS might act as both a constraint on and a cost of growth, yet studies investigating this have produced conflicting results. Here, we use meta-analysis to investigate whether increased OS levels impact on growth (OS as a constraint on growth) and whether greater growth rates can increase OS (OS as a cost of growth). The role of OS as a constraint on growth was supported by the meta-analysis. Greater OS, in terms of either increased damage or reduced levels of antioxidants, was associated with reduced growth although the effect depended on the experimental manipulation used. Our results also support an oxidative cost of growth, at least in terms of increased oxidative damage, although faster growth was not associated with a change in antioxidant levels. These findings that OS can act as a constrai...

氧化应激（Oxidative Stress, OS）作为生活史权衡（Life-History Trade-Offs）的近因机制，在现有学术文献中已被广泛报道。其中一类资源分配权衡与生长速率相关，理论研究认为氧化应激既可能对生长构成制约，也可能是生长的代价，但针对该问题的实证研究却得出了相互矛盾的结论。本研究采用元分析（Meta-Analysis）方法，旨在探究两个核心议题：一是氧化应激水平升高是否会对生长产生影响（即氧化应激作为生长的制约因素），二是更高的生长速率是否会提升氧化应激水平（即氧化应激作为生长的代价）。元分析结果支持了氧化应激作为生长制约因素的作用：无论是氧化损伤加剧还是抗氧化剂水平降低所表征的更高氧化应激水平，均与生长速率下降显著相关，不过该效应会因所采用的实验操控手段不同而有所差异。本研究结果同时验证了生长的氧化代价这一假说，至少在氧化损伤加剧的层面成立；尽管生长速率加快并未与抗氧化剂水平的变化存在关联。上述研究结果表明，氧化应激可作为一种制约...