Adipose tissue is an endocrine organ, secreting various adipokines, either directly or via extracellular vesicles, including exosomes. Exosomes are vesicles of 40–150 nm size that represent a novel concept of biomolecule release. We purified exosomes from isolated primary human preadipocytes differentiated to mature adipocytes. The analyses of these exosomal preparations by LC-MS identified 884 proteins, so called exoadipokines. The comparison of exoadipokines with previously identified human exosome-associated proteins in ExoCarta database show an overlap of 817 proteins, but also revealed 67 proteins not assigned to human exosomes, yet. We further compared all exoadipokines to our previously reported reference secretome of human adipose tissue (http://diabesityprot.org/), finding 212 common proteins, whereas 672 proteins were specific for the exosomal fraction. Bioinformatic analyses revealed that the 212 common proteins can be assigned to all major functions of adipose tissue secreted proteins e.g. molecules involved in fibrotic processes or inflammation. In contrast, the exosome-specific proteins were rather assigned to signaling pathways and membrane-mediated processes. In conclusion, the isolation of exosomes allows to further specify the functionality of adipokines and exoadipokines as part of the adipocyte secretome in signaling and interorgan crosstalk.

脂肪组织是一种内分泌器官，直接或通过细胞外囊泡（包括外泌体）分泌各种脂肪因子。外泌体是40-150 nm大小的囊泡，代表了生物分子释放的新概念。我们从分化为成熟脂肪细胞的原代人原脂肪细胞中纯化了外泌体。通过LC-MS对这些外泌体制剂进行的分析鉴定出了884种蛋白质，即所谓的外泌外表素。将Exoadipokines与先前在ExoCarta数据库中鉴定的人类外泌体相关蛋白进行比较，结果显示817种蛋白质有重叠，但还揭示了67种尚未分配给人类外泌体的蛋白质。我们进一步将所有外泌体辅因子与我们先前报道的人类脂肪组织参考分泌素组（http://diabesityprot.org/）进行了比较，发现了212种常见蛋白质，672种蛋白质对外泌体部分具有特异性。生物信息学分析表明，212种常见蛋白可以分配给脂肪组织分泌蛋白的所有主要功能，例如参与纤维化过程或炎症的分子。相反，外泌体特异性蛋白则被分配到信号传导途径和膜介导的过程中。总之，外泌体的分离使得可以进一步确定脂肪信号素和外脂肪表素作为信号传导和器官间串扰中脂肪细胞分泌组的一部分的功能。外泌体特异性蛋白被分配给信号传导途径和膜介导的过程。总之，外泌体的分离使得可以进一步确定脂肪信号素和外脂肪表素作为信号传导和器官间串扰中脂肪细胞分泌组的一部分的功能。外泌体特异性蛋白被分配给信号传导途径和膜介导的过程。总之，外泌体的分离使得可以进一步确定脂肪信号素和外脂肪因子作为信号传导和器官间串扰中脂肪细胞分泌组的一部分的功能。