激素性白内障的发病机制研究

Pathogenesis of steroid-induced cataract

糖皮质激素在许多生理过程中发挥重要作用,并被广泛应用于临床,在器官移植、战伤和免疫性疾病等救治过程中使用剂量更大。流行病学资料已证实长期全身、局部应用及吸入糖皮质激素治疗均可引起以晶状体后囊混浊为特征的激素性白内障。激素性白内障的发病机制复杂。主要形成了氧化损伤学说、蛋白加和物学说、激素通过受体途径而发挥作用的受体学说、离子转运障碍学说、晶状体结构蛋白和酶功能损害学说、细胞黏附分子异常学说。激素不仅可能直接攻击晶状体蛋白质,而且也可能通过受体、细胞调控、黏附调节等间接发挥作用。最近研究已证实晶状体上皮细胞中存在糖皮质激素受体,这将有助于阐明激素性白内障发生机制,为药物预防和治疗白内障提供新思路。

Glucocorticoids play an important role in many physiological processes and are widely used in medical practice, especially in treatment of diseases such as organ transplantation, military trauma and immunological diseases. Epidemiological studies have well documented that prolonged use of glucocorticoids with systemic, topical or inhaled steroid therapy can lead to the formation of a steroid-induced posterior subcapsular cataract. Although the mechanism of steroid-induced cataract is complex, several hypotheses have been proposed, such as oxidative damage, protein adduct formation, receptor mediated effects, ion transport obstacle, damage of lens structural protein or enzyme function and abnormal cell adhesion. Glucocorticoids can bind lens protein directly or act through its receptor, cell regulation, adhesion regulation indirectly. More recently, the presence of the receptor was definitely identified in human lens epithelia. This may lead to a better understanding of the mechanism of glucocorticoid action in the pathogenesis of a steroid-induced cataract, and provide a new thought for treatment and prevention.·