钙离子与天疱疮发病机制的研究进展

Role of calcium ions in the pathogenesis of pemphigus

Ca＋＋具有维持桥粒芯糖蛋白构象和加强黏附等功能，细胞钙离子紊乱是天疱疮发病机制中的重要环节。目前较为公认的天疱疮发病机制为多种自身抗体针对角质形成细胞相关抗原，激活相关信号通路，引起细胞内Ca＋＋浓度升高，活化蛋白激酶C，引起黏附分子磷酸化，黏附分子内化，角蛋白回缩，细胞骨架崩溃和桥粒解离；细胞内Ca＋＋浓度升高还可启动线粒体途径细胞凋亡/胀亡途径，caspases可以降解角蛋白，导致角蛋白回缩，直接介导桥粒结构相关蛋白结构和功能失调，影响原有的细胞骨架结构，致使棘层松解和细胞凋亡，该过程称为“松解凋亡”。

Calcium ion （Ca＋＋） can maintain the conformation of desmoglein and enhance desmosomal adhesion, and intracellular calcium ion abnormalities play an important role in the pathogenesis of pemphigus. Currently, it is acknowledged that the pathogenesis of pemphigus is associated with a variety of autoantibodies against keratinocyte-associated antigens, which can activate related signaling pathways, and lead to increases in intracellular calcium ion concentration, followed by activation of protein kinase C, phosphorylation and internalization of adhesion molecules, retraction of keratin, collapse of cytoskeleton and desmosome dissociation. Increases in intracellular calcium ion concentration can also initiate mitochondrial pathway-mediated apoptosis or oncosis. During this pathway, caspases can degrade keratin and cause keratin retraction on the one hand, as well as directly induce abnormalities in the structure and function of desmosomal proteins, and impact on original cytoskeleton structures on the other hand, finally leading to acantholysis and apoptosis, which is called “apoptolysis”.