Wells Jonathan C K
Childhood Nutrition Research Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC, UK.
Evol Med Public Health. 2018 Aug 16;2018(1):153-166. doi: 10.1093/emph/eoy014. eCollection 2018.
Lay Summary: This review sets out the hypothesis that life history trade-offs in the maternal generation favour the emergence of similar trade-offs in the offspring generation, mediated by the partitioning of maternal investment between pregnancy and lactation, and that these trade-offs help explain widely reported associations between growth trajectories and NCD risk. Growth patterns in early life predict the risk of non-communicable diseases (NCDs), but adaptive explanations remain controversial. It is widely assumed that NCDs occur either because of physiological adjustments to early constraints, or because early ecological cues fail to predict adult environmental conditions (mismatch). I present an inter-generational perspective on developmental plasticity, based on the over-arching hypothesis that a key axis of variability in maternal metabolism derives from life history trade-offs, which influence how individual mothers partition nutritional investment in their offspring between pregnancy and lactation. I review evidence for three resulting predictions: (i) Allocating relatively more energy to growth during development promotes the capacity to invest in offspring during pregnancy. Relevant mechanisms include greater fat-free mass and metabolic turnover, and a larger physical space for fetal growth. (ii) Allocating less energy to growth during development constrains fetal growth of the offspring, but mothers may compensate by a tendency to attain higher adiposity around puberty, ecological conditions permitting, which promotes nutritional investment during lactation. (iii) Since the partitioning of maternal investment between pregnancy and lactation impacts the allocation of energy to 'maintenance' as well as growth, it is expected to shape offspring NCD risk as well as adult size and body composition. Overall, this framework predicts that life history trade-offs in the maternal generation favour the emergence of similar trade-offs in the offspring generation, mediated by the partitioning of maternal investment between pregnancy and lactation, and that these trade-offs help explain widely reported associations between growth trajectories and NCD risk.
本综述提出了一个假设，即母代的生活史权衡有利于子代出现类似的权衡，这是由母代在怀孕和哺乳期间的投资分配介导的，并且这些权衡有助于解释广泛报道的生长轨迹与非传染性疾病风险之间的关联。生命早期的生长模式可预测非传染性疾病（NCDs）的风险，但适应性解释仍存在争议。人们普遍认为，非传染性疾病的发生要么是由于对早期限制的生理调整，要么是由于早期生态线索未能预测成年后的环境条件（错配）。我基于一个总体假设，即母代新陈代谢变异性的一个关键轴源自生活史权衡，提出了一个关于发育可塑性的代际观点，这种权衡影响个体母亲如何在怀孕和哺乳期间将营养投资分配给后代。我回顾了由此产生的三个预测的证据：（i）在发育过程中分配相对更多的能量用于生长，可促进怀孕期对子代的投资能力。相关机制包括更大的去脂体重和代谢周转率，以及更大的胎儿生长物理空间。（ii）在发育过程中分配较少的能量用于生长会限制子代的胎儿生长，但在生态条件允许的情况下，母亲可能会通过在青春期前后倾向于获得更高的肥胖度来进行补偿，这有利于哺乳期间的营养投资。（iii）由于母代在怀孕和哺乳期间的投资分配会影响能量在“维持”和生长之间的分配，因此预计它会塑造子代的非传染性疾病风险以及成年后的体型和身体组成。总体而言，该框架预测，母代的生活史权衡有利于子代出现类似的权衡，这是由母代在怀孕和哺乳期间的投资分配介导的，并且这些权衡有助于解释广泛报道的生长轨迹与非传染性疾病风险之间的关联。
