Noguera José Carlos, da Silva Alberto, Velando Alberto
Grupo de Ecología Animal (GEA), Centro de Investigacion Mariña (CIM), Universidad de Vigo, Vigo, 36310, Spain.
Mol Ecol. 2022 Dec;31(23):6252-6260. doi: 10.1111/mec.15694. Epub 2020 Nov 3.
It is often assumed that the transfer of maternal glucocorticoids (GCs; e.g., corticosterone or cortisol) to offspring is an inevitable cost associated with adverse or stressful conditions experienced by mothers. However, recent evidence indicates that maternal GCs may adaptively programme particular physiological and molecular pathways during development to enhance offspring fitness. In this context, an important mechanism through which maternal GCs may lastingly affect offspring phenotypic quality and survival is via effects on embryo telomerase activity and so on offspring postnatal telomere length. Here, using a field experimental design for which we manipulated the corticosterone content in yellow-legged gull (Larus michahellis) eggs, we show that embryos from corticosterone-injected eggs not only had a higher telomerase activity but also longer telomeres just after hatching. A complementary analysis further revealed that gull hatchlings with longer telomeres had a higher survival probability during the period when most of the chick mortality occurs. Given the important role that telomere length and its restoring mechanisms have on ageing trajectories and disease risk, our findings provide a new mechanistic link by which mothers may presumably shape offspring life-history trajectories and phenotype.
人们常常认为，母体糖皮质激素（GCs；如皮质酮或皮质醇）向后代的转移是与母亲所经历的不良或应激条件相关的一种不可避免的代价。然而，最近的证据表明，母体糖皮质激素可能在发育过程中适应性地设定特定的生理和分子途径，以提高后代的适应性。在这种情况下，母体糖皮质激素可能持久影响后代表型质量和生存的一个重要机制是通过对胚胎端粒酶活性以及后代出生后端粒长度的影响。在这里，我们采用田间实验设计，操纵黄腿鸥（Larus michahellis）卵中的皮质酮含量，结果表明，注射皮质酮的卵所孵化出的胚胎不仅在刚孵化后具有更高的端粒酶活性，而且端粒更长。一项补充分析进一步揭示，端粒较长的鸥幼雏在雏鸟死亡最频繁的时期具有更高的存活概率。鉴于端粒长度及其修复机制在衰老轨迹和疾病风险方面的重要作用，我们的研究结果提供了一个新的机制联系，据此母亲可能塑造后代的生活史轨迹和表型。
