Huang Li, Estrada Rosendo, Yappert Marta C, Borchman Douglas
Department of Ophthalmology and Visual Science, University of Louisville, University of Louisville, Louisville, KY 40202, USA.
Free Radic Biol Med. 2006 Nov 1;41(9):1425-32. doi: 10.1016/j.freeradbiomed.2006.07.022. Epub 2006 Aug 4.
Lipid compositional changes in lens epithelial cells (HLE B-3) grown in a hyperoxic atmosphere were studied to determine if oxidation could cause changes in the amount and type of phospholipid similar to those found in vivo with age and cataract. The phosphatidylcholines in HLE B-3 cells were 8 times more unsaturated than the sphingomyelins. Cell viability was the same for cells grown for up to 48 h in a normoxic or hyperoxic atmosphere. Lipid oxidation was about three times higher after growth in a hyperoxic atmosphere compared with cells grown in a normoxic atmosphere. The lack of change in the relative amount of sphingomyelin and the decrease in phosphatidylcholine coupled with the increase in lysophosphatidylcholine support the idea that similar mechanisms may be responsible for the lipid compositional changes in both lens epithelial and fiber cells. It is postulated that lipases eliminate oxidized unsaturated glycerolipids, leaving a membrane increasingly composed of more ordered and more saturated sphingolipids. Oxidative stress leads to changes in membrane composition that are consistent with those seen with age in human epithelial cells. Oxidation-induced epithelial phospholipid change is an area of research that has gone virtually unexplored in the human lens and could be relevant to all cell types and may be important to lens clarity.
研究了在高氧环境中生长的晶状体上皮细胞（HLE B-3）的脂质组成变化，以确定氧化是否会导致磷脂的数量和类型发生变化，类似于在体内随年龄增长和白内障出现时所发现的变化。HLE B-3细胞中的磷脂酰胆碱的不饱和程度比鞘磷脂高8倍。在常氧或高氧环境中培养长达48小时的细胞，其细胞活力相同。与在常氧环境中生长的细胞相比，在高氧环境中生长后脂质氧化大约高3倍。鞘磷脂相对含量没有变化，磷脂酰胆碱减少，同时溶血磷脂酰胆碱增加，这支持了类似机制可能导致晶状体上皮细胞和纤维细胞脂质组成变化的观点。据推测，脂肪酶会消除氧化的不饱和甘油脂，使膜越来越多地由更有序、更饱和的鞘脂组成。氧化应激导致膜组成的变化与人类上皮细胞随年龄增长所见的变化一致。氧化诱导的上皮磷脂变化是一个在人类晶状体中几乎未被探索的研究领域，可能与所有细胞类型相关，并且可能对晶状体透明度很重要。
