Universiti Teknologi MARA, Faculty of Medicine, Level 20, Tower 1, Science & Technology Complex, 40450 Shah Alam, Selangor, Malaysia.
Exp Eye Res. 2012 Aug;101:82-9. doi: 10.1016/j.exer.2012.05.008. Epub 2012 Jun 2.
Magnesium is one of the most important regulatory cation involved in several biological processes. It is important for maintaining the structural and functional integrity of vital ocular tissues such as lens. Presence of high magnesium content especially in the peripheral part of lens as compared to aqueous and vitreous humor has been observed. Magnesium plays significant role as a cofactor for more than 350 enzymes in the body especially those utilizing ATP. Membrane associated ATPase functions that are crucial in regulating the intracellular ionic environment, are magnesium-dependent. Moreover, the enzymes involved in ATP production and hydrolysis are also magnesium-dependent. Magnesium deficiency by interfering with ATPase functions causes increased intracellular calcium and sodium and decreases intracellular potassium concentration. Furthermore, magnesium deficiency is associated with increased oxidative stress secondary to increased expression of inducible nitric oxide synthase and increased production of nitric oxide. Thus the alterations in lenticular redox status and ionic imbalances form the basis of the association of magnesium deficiency with cataract. In this paper we review the mechanisms involved in magnesium homeostasis and the role of magnesium deficiency in the pathogenesis of cataract.
镁是参与多种生物过程的最重要的调节阳离子之一。它对维持晶状体等重要眼部组织的结构和功能完整性很重要。观察到晶状体的外围部分（与房水和玻璃体相比）含有高镁含量。镁作为 350 多种酶在体内的辅助因子发挥重要作用，特别是那些利用 ATP 的酶。与调节细胞内离子环境有关的膜相关 ATP 酶功能依赖于镁。此外，参与 ATP 生成和水解的酶也依赖于镁。通过干扰 ATP 酶功能导致细胞内钙和钠增加，钾浓度降低，从而导致镁缺乏。此外，由于诱导型一氧化氮合酶表达增加和一氧化氮产生增加，镁缺乏与氧化应激增加有关。因此，晶状体氧化还原状态和离子失衡的改变构成了镁缺乏与白内障之间关联的基础。在本文中，我们综述了镁动态平衡的机制以及镁缺乏在白内障发病机制中的作用。
