应用MR氢谱检测大鼠脑胶质瘤C6细胞放射损伤

目的 应用高分辨率MR氢谱检测大鼠脑胶质瘤细胞系C6的放射损伤并初步探讨其机制。方法 以C6细胞为研究对象,应用MR氢谱检测细胞内多种代谢物浓度;彗星实验检测DNA损伤;流式细胞术检测周期进程及凋亡率;克隆形成实验观察克隆形成率并初步探讨放射损伤作用机制。采用单因素方差分析,Pearson法相关分析。结果 照射剂量由0 Gy增加为1、5、10、15 Gy时,DNA损伤逐渐加重且有剂量依赖性(P=0.000~0.690), G₁期所占百分比显著增加(P=0.026~0.749),凋亡率逐渐上升(P=0.000~0.000),克隆形成率逐渐降低(P=0.000~0.004);同时,代谢物比值Lac/Cr逐渐减少(P=0.000~0.015),与DNA损伤参数(尾长、彗尾中DNA含量、尾矩)呈线性负相关(r=-0.971、-0.998、-0.995),与凋亡率呈线性负相关(r=-0.978)。结论 MR氢谱检测发现C6细胞照射后Lac/Cr比值变化与肿瘤细胞凋亡有明显相关性,MR氢谱具有预测脑胶质瘤放射损伤的潜力。

A study of radiation injury in rat C6 glioma cell line by 1H-nuclear magnetic resonance spectroscopy

Objective To study the radiation injury of rat C6 glioma cell line by high resolution,1 H-nuclear magnetic resonance (1 H NMR) spectroscopy,and to preliminarily investigate its mechanism.Methods Metabolite concentrations in C6 cells were determined by 1 H NMR spectroscopy.Comet assay was used to evaluate DNA damage.Flow cytometry was used to determine the cell cycle and apoptosis rate.Colony-forming assay was used to measure the colony-forming rate and preliminarily investigate the mechanism of radiation injury.The resuhs were analyzed by one-way analysis of variance and Pearson correlation analysis.Results With the increase in radiation dose from 0 Gy to 1,5,10,and 15 Gy,DNA damage was enhanced in a dose-dependent manner (P=0.000-0.690);the percentage of cells in G1 phase increased (P =0.026-0.749);the apoptosis rate significantly increased (all P =0.000);the colony-forming rate significantly declined (P =0.000-0.004);the Lac/Cr ratio significantly decreased (P =0.000-0.015),which had a negative linear correlation with DNA damage parameters (tail length,r=-0.971;％DNA in the tail,r =-0.998;tail moment,r =-0.995) and apoptosis rate (r =0.978).Conclusions 1 H NMR spectroscopy reveals that the change in the Lac/Cr ratio is associated with injury and apoptosis of C6 cells after radiation.1 H NMR spectroscopy has the potential to predict radiation injury of glioma.