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 hypothesised 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 by investigating individual probability of recapture in the following two years. Results show a strong decrease in glycated haemoglobin from one to five years and a slight 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 comes at a cost of survival in this natural bird population, and that the selective disappearance of individuals with the highest glycation levels is accounting for the counter-intuitive 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，但我们对该过程在野生自由生活动物中的重要性仍知之甚少。血糖调控不佳会引发不可逆的蛋白质糖基化（protein glycation），因此学界推测蛋白质糖基化水平会随年龄增长而升高，并与存活率下降相关。我们通过对274只已知年龄的成年白领姬鹟（collared flycatchers）开展血液糖化血红蛋白（glycated haemoglobin）检测，并追踪其后续两年的个体重捕概率，验证了上述两项预测。结果显示，糖化血红蛋白水平在1至5岁龄间显著下降，此后则呈轻微上升趋势。即使在控制年龄和扩散效应的影响后，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会以存活率为代价；而糖基化水平最高的个体发生选择性消失，正是造成早期年龄组中糖化血红蛋白水平随年龄增长出现反直觉下降的原因。