Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital-The Norwegian Radium Hospital, 0379 Oslo, Norway; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, 0379 Oslo, Norway.
Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital-The Norwegian Radium Hospital, 0379 Oslo, Norway; Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, 0379 Oslo, Norway; Department of Molecular Biosciences, University of Oslo, 0316 Oslo, Norway.
Prog Lipid Res. 2017 Apr;66:30-41. doi: 10.1016/j.plipres.2017.03.001. Epub 2017 Mar 23.
Lipids are essential components of exosomal membranes, and it is well-known that specific lipids are enriched in exosomes compared to their parent cells. In this review we discuss current knowledge about the lipid composition of exosomes. We compare published data for different lipid classes in exosomes, and what is known about their lipid species, i.e. lipid molecules with different fatty acyl groups. Moreover, we elaborate on the hypothesis about hand-shaking between the very-long-chain sphingolipids in the outer leaflet and PS 18:0/18:1 in the inner leaflet, and we propose this to be an important mechanism in membrane biology, not only for exosomes. The similarity between the lipid composition of exosomes, HIV particles, and detergent resistant membranes, used as lipid rafts models, is also discussed. Furthermore, we summarize knowledge about the role of specific lipids and lipid metabolizing enzymes on the formation and release of exosomes. Finally, the use of exosomal lipids as biomarkers and how the lipid composition of exosomes may be of importance for researchers aiming to use exosomes as drug delivery vehicles is discussed. In conclusion, we have summarized what is presently known about lipids in exosomes and identified issues that should be taken into consideration in future studies.
脂质是外泌体膜的必需成分，众所周知，与亲代细胞相比，外泌体中特定的脂质更为丰富。在这篇综述中，我们讨论了关于外泌体脂质组成的现有知识。我们比较了不同外泌体中不同脂质类别的已发表数据，以及它们的脂质种类（即具有不同脂肪酸酰基的脂质分子）的已知信息。此外，我们详细阐述了关于非常长链鞘氨醇在外侧叶和 PS 18:0/18:1 在内侧叶之间“握手”的假说，并提出这是膜生物学中的一个重要机制，不仅对于外泌体而言。还讨论了外泌体、HIV 颗粒和用作脂筏模型的去污剂抗性膜之间的脂质组成的相似性。此外，我们总结了关于特定脂质和脂质代谢酶在形成和释放外泌体中的作用的知识。最后，讨论了外泌体脂质作为生物标志物的用途，以及外泌体的脂质组成对于希望将外泌体用作药物递送载体的研究人员的重要性。总之，我们总结了目前已知的关于外泌体脂质的知识，并确定了在未来研究中应考虑的问题。
