Data from: Selective disappearance of individuals with high levels of glycated haemoglobin in a free-living bird

Although disruption of glucose homeostasis is a hallmark of ageing in humans and laboratory model organisms, we have little information on the importance of this process in free-living animals. Poor control of blood glucose levels leads to irreversible protein glycation. Hence, levels of protein glycation are hypothesized to increase with age and to be associated with a decline in survival. We tested these predictions by measuring blood glycated haemoglobin in 274 adult collared flycatchers of known age and estimating individual probability of recapture in the following 2 years. Results show a strong decrease in glycated haemoglobin from age 1 to 5 years and an increase thereafter. Individuals with high levels of glycated haemoglobin had a lower probability of recapture, even after controlling for effects of age and dispersal. Altogether, our findings suggest that poor control of glucose homoeostasis is associated with lower survival in this free-living bird population, and that the selective disappearance of individuals with the highest glycation levels could account for the counterintuitive age-related decline in glycated haemoglobin in the early age categories.

尽管葡萄糖稳态（glucose homeostasis）紊乱是人类及实验室模式生物衰老的标志性特征，但我们对这一过程在野生自由生活动物中的重要性知之甚少。血糖调控不佳会引发不可逆的蛋白质糖基化（protein glycation）。据此，学界推测蛋白质糖基化水平会随年龄增长而升高，且与存活率降低存在关联。本研究通过检测274只已知年龄的成年领姬鹟（collared flycatcher）血液中的糖化血红蛋白（glycated haemoglobin）水平，并估算其未来两年的个体重捕（recapture）概率，对上述假说进行了验证。研究结果显示，糖化血红蛋白水平在1至5岁龄间显著下降，5岁龄之后则出现升高。即便在控制了年龄与扩散（dispersal）效应的前提下，糖化血红蛋白水平较高的个体，其重捕概率依然更低。综合来看，本研究结果表明，在该野生鸟类种群中，葡萄糖稳态调控不佳与存活率降低存在关联；而糖基化水平最高的个体发生选择性消失，或可解释早期年龄组中糖化血红蛋白水平随年龄增长反而下降这一与直觉相悖的现象。