Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México, DF Mexico.
Liver Int. 2011 Oct;31(9):1271-84. doi: 10.1111/j.1478-3231.2011.02542.x. Epub 2011 May 3.
Liver regeneration is a compensatory hyperplasia produced by several stimuli that promotes proliferation in order to provide recovery of the liver mass and architecture. This process involves complex signalling cascades that receive feedback from autocrine and paracrine pathways, recognized by parenchymal as well as non-parenchymal cells. Nowadays the dynamic role of lipids in biological processes is widely recognized; however, a systematic analysis of their importance during liver regeneration is still missing. Therefore, in this review we address the role of lipids including the bioactive ones such as sphingolipids, but with special emphasis on cholesterol. Cholesterol is not only considered as a structural component but also as a relevant lipid involved in the control of the intermediate metabolism of different liver cell types such as hepatocytes, hepatic stellate cells and Kupffer cells. Cholesterol plays a significant role at the level of specific membrane domains, as well as modulating the expression of sterol-dependent proteins. Moreover, several enzymes related to the catabolism of cholesterol and whose activity is down regulated are related to the protection of liver tissue from toxicity during the process of regeneration. This review puts in perspective the necessity to study and understand the basic mechanisms involving lipids during the process of liver regeneration. On the other hand, the knowledge acquired in this area in the past years, can be considered invaluable in order to provide further insights into processes such as general organogenesis and several liver-related pathologies, including steatosis and fibrosis.
肝脏再生是由多种刺激因素引起的代偿性增生，促进增殖以提供肝质量和结构的恢复。这个过程涉及复杂的信号级联反应，会从自分泌和旁分泌途径获得反馈，这些反馈由实质细胞和非实质细胞识别。如今，人们广泛认识到脂质在生物过程中的动态作用；然而，它们在肝脏再生过程中的重要性仍缺乏系统分析。因此，在这篇综述中，我们探讨了脂质的作用，包括生物活性脂质如鞘脂，但特别强调胆固醇。胆固醇不仅被认为是结构成分，而且还是参与控制不同肝实质细胞（如肝细胞、肝星状细胞和枯否细胞）中间代谢的相关脂质。胆固醇在特定膜域水平上发挥重要作用，同时调节固醇依赖性蛋白的表达。此外，与胆固醇分解代谢相关的几种酶的活性受到下调，这些酶与保护肝组织免受再生过程中的毒性有关。这篇综述从需要研究和理解肝脏再生过程中涉及脂质的基本机制的角度出发。另一方面，在过去几年中在这一领域获得的知识，可以被认为是无价的，以便为一般器官发生和几种与肝脏相关的病理过程（包括脂肪变性和纤维化）提供更深入的见解。
