Amato Katherine R, Pradhan Priyanka, Mallott Elizabeth K, Shirola Wesley, Lu Amy
Department of Anthropology, Northwestern University, Evanston, IL 60208, USA.
Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
Evol Med Public Health. 2024 Jan 6;12(1):7-23. doi: 10.1093/emph/eoae001. eCollection 2024.
Mammalian pregnancy is characterized by a well-known suite of physiological changes that support fetal growth and development, thereby positively affecting both maternal and offspring fitness. However, mothers also experience trade-offs between current and future maternal reproductive success, and maternal responses to these trade-offs can result in mother-offspring fitness conflicts. Knowledge of the mechanisms through which these trade-offs operate, as well as the contexts in which they operate, is critical for understanding the evolution of reproduction. Historically, hormonal changes during pregnancy have been thought to play a pivotal role in these conflicts since they directly and indirectly influence maternal metabolism, immunity, fetal growth and other aspects of offspring development. However, recent research suggests that gut microbiota may also play an important role. Here, we create a foundation for exploring this role by constructing a mechanistic model linking changes in maternal hormones, immunity and metabolism during pregnancy to changes in the gut microbiota. We posit that marked changes in hormones alter maternal gut microbiome composition and function both directly and indirectly via impacts on the immune system. The gut microbiota then feeds back to influence maternal immunity and metabolism. We posit that these dynamics are likely to be involved in mediating maternal and offspring fitness as well as trade-offs in different aspects of maternal and offspring health and fitness during pregnancy. We also predict that the interactions we describe are likely to vary across populations in response to maternal environments. Moving forward, empirical studies that combine microbial functional data and maternal physiological data with health and fitness outcomes for both mothers and infants will allow us to test the evolutionary and fitness implications of the gestational microbiota, enriching our understanding of the ecology and evolution of reproductive physiology.
哺乳动物的怀孕具有一系列众所周知的生理变化，这些变化支持胎儿的生长和发育，从而对母体和后代的健康产生积极影响。然而，母亲在当前和未来的母体生殖成功之间也会面临权衡，而母体对这些权衡的反应可能会导致母婴健康冲突。了解这些权衡发生的机制以及它们发生的背景，对于理解生殖的进化至关重要。从历史上看，怀孕期间的激素变化被认为在这些冲突中起着关键作用，因为它们直接或间接地影响母体代谢、免疫、胎儿生长以及后代发育的其他方面。然而，最近的研究表明，肠道微生物群可能也起着重要作用。在这里，我们通过构建一个将怀孕期间母体激素、免疫和代谢的变化与肠道微生物群的变化联系起来的机制模型，为探索这一作用奠定基础。我们假定，激素的显著变化会直接或通过对免疫系统的影响间接改变母体肠道微生物群的组成和功能。然后，肠道微生物群会反馈影响母体免疫和代谢。我们假定，这些动态变化可能参与调节母体和后代的健康，以及怀孕期间母体和后代健康与 fitness 不同方面的权衡。我们还预测，我们所描述的相互作用可能会因母体环境的不同而在不同人群中有所变化。展望未来，将微生物功能数据和母体生理数据与母亲和婴儿的健康与 fitness 结果相结合的实证研究，将使我们能够测试妊娠微生物群的进化和 fitness 影响，丰富我们对生殖生理学的生态和进化的理解。
