涎腺放射性损伤机制及其防治的研究进展

对头颈部恶性肿瘤进行放射治疗，不可避免地引起涎腺的放射损伤，严重影响患者生活质量。放射性涎腺损伤的主要临床和功能改变为腺体肿胀，涎液分泌减少，涎液电解质和蛋白质分泌异常等；其主要病理变化是腺泡细胞变性萎缩、导管扩张、间质纤维化以及淋巴细胞浸润等；其机制与p53信号分子通路介导的细胞凋亡、活性氧所致的膜损伤作用、水通道蛋白1和5表达降低、腱糖蛋白一c和胞外基质蛋白表达增加以及血管内皮细胞损伤等因素密切相关；改进放射治疗技术、颌下腺移植转位保护及合理应用细胞保护剂和促涎剂，可以减轻放射性涎腺损伤。本文对涎腺放射损伤的分子机制及其防治进展进行综述。

Mechanism and preventive treatment of irradiated salivary gland injury

Radiation therapy for head and neck cancer inevitably causes radiogenic salivary gland injury,resulting in diminished life quality of the patients.The major clinical and functional changes of irradiated salivary gland damage include swollen glands,dramatically reduced saliva secretion,and abnormal secretion of electrolyte and protein in saliva.The most prominent pathological changes of radiation-induced salivary impairment are pyknotic nuclei,vacuolization of acinar cells,lysis of acinar cells,dilated duct,fibrosis of mesenchyma,and lymphocytic infiltration.The underlying mechanisms might be closely related to factors such as p53 depended apoptosis signaling pathway,reactive oxygen induced membrane injury,decreased expressions of aquaporin-1 and aquaporin-5,increased expressions of tenascin-C and extracellular matrix proteins,and damage of vascular endothelial cells.By improving radiotherapy,performing autologous submandibular gland transplantation,and appropriately utilizing cytoprotectants and sialagogues,salivary gland injury could be effectively alleviated.This review will discuss the molecular mechanisms and the preventive treatments of radiation-induced salivary gland impairment.