Background:Radiation-induced salivary gland (SG) hypofunction is mediated via microvascular dysfunction and radical oxygen species. N-acetylcysteine amide (NACA) has shown antioxidant properties with low toxicity. We explored NACA’s potential as a radioprotector of SG function.Methods:Bovine aortic endothelial cells (BAECs) were treated with NACA before irradiation with a single 10 Gy dose. Apoptosis was assessed by bis-benzimide staining and quantified via fluorescence microscopy. In vivo, NACA was administered to mice prior to a single 15 Gy head and neck irradiation. Eight weeks post-irradiation, saliva production was measured using pilocarpine stimulation; lysozyme levels were analyzed by ELISA. SGs were collected for immunohistochemistry.Results:BAEC apoptosis was substantially lower in NACA-treated cells vs. radiation-only (10% vs. 23%). In vivo, mice lost significant weight and developed severe hair loss eight weeks post-irradiation—attenuated by NACA pretreatment. Saliva production was reduced by 72% post-radiation, with a corresponding drop in lysozyme. NACA increased salivary flow by 42% and prevented lysozyme reduction. Post-radiation decline in microvessel density was also prevented by NACA.Conclusions:These outcomes suggest NACA may serve as a radioprotector of SG function in patients undergoing radiotherapy for head and neck cancer.
背景：辐射诱导的唾液腺功能减退是通过微血管功能障碍和活性氧介导的。N-乙酰半胱酰胺（NACA）已显示出低毒性的抗氧化特性。本研究探讨了NACA作为唾液腺功能辐射防护剂的潜力。 方法：在单次10 Gy剂量照射前，用NACA处理牛主动脉内皮细胞（BAECs）。通过双苯甲亚胺染色评估细胞凋亡，并通过荧光显微镜进行定量分析。在体内实验中，小鼠在单次15 Gy头颈部照射前接受NACA给药。照射后八周，使用毛果芸香碱刺激测量唾液分泌量；通过酶联免疫吸附法分析溶菌酶水平。收集唾液腺进行免疫组织化学分析。 结果：与仅接受辐射的细胞相比，NACA处理的BAECs细胞凋亡显著降低（10% vs. 23%）。在体内实验中，照射后八周小鼠出现显著体重下降和严重脱毛，而NACA预处理减轻了这些症状。辐射后唾液分泌量减少72%，溶菌酶水平相应下降。NACA使唾液流量增加42%，并防止了溶菌酶减少。辐射后微血管密度的下降同样被NACA所阻止。 结论：这些结果表明，NACA可能作为头颈癌放疗患者唾液腺功能的辐射防护剂。
N-Acetylcysteine Amide Is a Potential Novel Radioprotector of Salivary Gland Function
肿瘤(癌症)患者之家