Velauthapillai Nivethan, Barfett Joe, Jaffer Hussein, Mikulis David, Murphy Kieran
Department of Medical Imaging, Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, ON M5T 2S8, Canada.
Department of Medical Imaging, Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, ON M5T 2S8, Canada.
J Vasc Interv Radiol. 2017 Mar;28(3):406-411. doi: 10.1016/j.jvir.2016.10.022. Epub 2016 Dec 26.
To evaluate efficacy of oral antioxidant treatment given to patients before radiologic procedures in reducing x-ray-induced DNA damage.
In a single-center prospective controlled trial, antioxidant treatment with 2 g ascorbate, 1.2 g N-acetylcysteine, 600 mg lipoic acid, and 30 mg beta carotene was given to 5 consecutive participants before undergoing clinically indicated technetium-99m methylene diphosphonate (Tc MDP) bone scans for cancer staging. These participants were compared with 5 participants without antioxidant treatment. DNA damage was visualized in peripheral blood mononuclear cells (PBMCs) before and after bone scans using three-dimensional microscopy and fluorescently labeled gamma-H2AX protein. Wilcoxon rank sum test was used to determine whether there was a statistically significant difference in the radiation received between the control and antioxidant groups, the number of foci/cell before and after bone scan within groups, and foci/cell after bone scan between groups.
There was a significantly higher number of gamma-H2AX foci/cell after ionization radiation in the control group compared with the antioxidant group (P = .009). There was no statistically significant difference in number of gamma-H2AX foci/cell before or after exposure in the antioxidant group; the number of gamma-H2AX foci/cell was statistically significantly higher (P = .009) in the control group after exposure to Tc MDP.
In patients undergoing Tc MDP bone scans, treatment with oral antioxidants before scanning significantly prevented DNA damage in PBMCs. Antioxidants may provide an effective means to protect patients and health care professionals from radiation-induced DNA damage during imaging studies.
评估在放射检查前给予患者口服抗氧化剂治疗对减少X射线诱导的DNA损伤的疗效。
在一项单中心前瞻性对照试验中，对连续5名即将接受临床指示的锝-99m亚甲基二膦酸盐（Tc MDP）骨扫描以进行癌症分期的参与者，给予含2 g抗坏血酸、1.2 g N-乙酰半胱氨酸、600 mg硫辛酸和30 mgβ-胡萝卜素的抗氧化剂治疗。将这些参与者与5名未接受抗氧化剂治疗的参与者进行比较。在骨扫描前后，使用三维显微镜和荧光标记的γ-H2AX蛋白观察外周血单个核细胞（PBMC）中的DNA损伤情况。采用Wilcoxon秩和检验来确定对照组和抗氧化剂组之间接受的辐射是否存在统计学显著差异、组内骨扫描前后每细胞的病灶数以及组间骨扫描后每细胞的病灶数。
与抗氧化剂组相比，对照组在电离辐射后每细胞的γ-H2AX病灶数显著更高（P = 0.009）。抗氧化剂组在暴露前后每细胞的γ-H2AX病灶数无统计学显著差异；在暴露于Tc MDP后，对照组每细胞的γ-H2AX病灶数在统计学上显著更高（P = 0.009）。
在接受Tc MDP骨扫描的患者中，扫描前口服抗氧化剂治疗可显著预防PBMC中的DNA损伤。抗氧化剂可能为保护患者和医护人员在成像研究期间免受辐射诱导的DNA损伤提供一种有效手段。
