Domer Adi, Misraje Tyler R, Xing Dianna, Arango B Gabriela, Selleghin-Veiga Giovanna, Corl Ammon, Bowie Rauri C K, McGuire Jimmy A, Sweazea Karen L, Vázquez-Medina José Pablo, Dudley Robert
Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, USA.
Evolutionary Genomics Laboratory, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, State University of Campinas, Campinas, Brazil.
Sci Adv. 2025 Sep 5;11(36):eadv2794. doi: 10.1126/sciadv.adv2794.
Being naturally hyperglycemic and insulin insensitive, birds maintain plasma glucose levels twice as high as mammals of similar size. Recent evidence suggests that perturbation of myo-inositol (MI) plays a role in mammalian hyperglycemic regulation. Using an integrative approach, we identify a fundamental role of MI in avian metabolism. We show that MI transporters are highly conserved across birds and that dietary MI reduces fat accumulation in Anna's hummingbirds. MI consumption by hummingbirds varies with seasonal changes in body mass, consistent with a regulatory role. Furthermore, MI enhances fatty acid oxidation in avian cells, via effects on pyruvate-dehydrogenase complexes, indicating a role in mitochondrial fuel selection. Our findings underscore the importance of MI in avian metabolism, offering insights into their evolutionary adaptations in the context of insulin insensitivity.
鸟类天生血糖高且对胰岛素不敏感，其血浆葡萄糖水平维持在与它们体型相似的哺乳动物的两倍。最近的证据表明，肌醇（MI）的扰动在哺乳动物高血糖调节中起作用。我们采用综合方法，确定了MI在鸟类新陈代谢中的基本作用。我们发现MI转运蛋白在鸟类中高度保守，并且饮食中的MI可减少安娜氏蜂鸟的脂肪积累。蜂鸟对MI的消耗随体重的季节性变化而变化，这与调节作用一致。此外，MI通过对丙酮酸脱氢酶复合物的作用增强鸟类细胞中的脂肪酸氧化，表明其在线粒体燃料选择中起作用。我们的研究结果强调了MI在鸟类新陈代谢中的重要性，为它们在胰岛素不敏感背景下的进化适应提供了见解。
