PDF(Pubmed)
Abstract：
Glucose is a central metabolic compound used as an energy source across all animal taxa. There is high interspecific variation in glucose concentration between taxa, the origin and the consequence of which remain largely unknown. Nutrition may affect glucose concentrations because carbohydrate content of different food sources may determine the importance of metabolic pathways in the organism. Birds sustain high glucose concentrations that may entail the risks of oxidative damage. We collected glucose concentration and life-history data from 202 bird species from 171 scientific publications, classified them into seven trophic guilds and analysed the data with a phylogenetically controlled model. We show that glucose concentration is negatively associated with body weight and is significantly associated with trophic guilds with a moderate phylogenetic signal. After controlling for allometry, glucose concentrations were highest in carnivorous birds, which rely on high rates of gluconeogenesis to maintain their glycaemia, and lowest in frugivorous/nectarivorous species, which take in carbohydrates directly. However, trophic guilds with different glucose concentrations did not differ in lifespan. These results link nutritional ecology to physiology and suggest that at the macroevolutionary scale, species requiring constantly elevated glucose concentrations may have additional adaptations to avoid the risks associated with high glycaemia.
摘要：
葡萄糖是在所有动物类群中用作能量来源的中心代谢化合物。分类群之间的葡萄糖浓度有很高的种间差异，其起源和后果在很大程度上仍然未知。营养可能会影响葡萄糖浓度，因为不同食物来源的碳水化合物含量可能决定生物体中代谢途径的重要性。鸟类维持高葡萄糖浓度，这可能带来氧化损伤的风险。我们从171种科学出版物中收集了202种鸟类的葡萄糖浓度和生活史数据，将它们分为七个营养协会，并用系统发育控制模型分析数据。我们表明，葡萄糖浓度与体重呈负相关，并且与具有中等系统发育信号的营养协会显着相关。控制异速测后，食肉鸟类的葡萄糖浓度最高，它们依靠高糖异生率来维持血糖，最低的是食果/蜜食物种，直接摄入碳水化合物。然而,不同葡萄糖浓度的营养行会的寿命没有差异。这些结果将营养生态学与生理学联系起来，并表明在宏观进化尺度上，需要不断升高葡萄糖浓度的物种可能会有额外的适应措施，以避免与高血糖相关的风险。
