Emerit I, Arutyunyan R, Oganesian N, Levy A, Cernjavsky L, Sarkisian T, Pogossian A, Asrian K
Department of Genetics, Institut Biomédical des Cordeliers, Université Paris VI, France.
Free Radic Biol Med. 1995 Jun;18(6):985-91. doi: 10.1016/0891-5849(94)00220-e.
Clastogenic factors (CFs) were first described in the blood of persons irradiated accidentally or for therapeutic reasons. Work of our laboratory has shown that they occur also under other circumstances, which are characterized by oxidative stress, and that CF-induced chromosome damage is regularly prevented by superoxide dismutase (SOD). Recently we found CFs in a high percentage of salvage personnel of the Chernobyl reactor accident. These liquidators represent a high-risk population and might benefit from cancer chemoprevention by antioxidants. SOD would have to be injected and is not appropriate for long-term prophylactic treatment. In the present study, we therefore evaluated the anticlastogenic effect of the Ginkgo biloba extract EGb 761, which is known for its superoxide scavenging properties. EGb 761 was tested on CF-treated blood cultures of healthy donors. After establishing the optimal protective EGb concentration, using CFs produced by irradiation of whole blood from healthy volunteers, the extract was tested on cultures exposed to CFs from plasma of persons irradiated as liquidators. The anticlastogenic effect could be confirmed for a final concentration of 100 micrograms/ml. In 12 consecutive experiments, CFs induced an average of 18.00 +/- 4.41 aberrations/100 cells. This was reduced to 7.33 +/- 3.08 in the parallel cultures receiving 100 micrograms/ml EGb 761 (p < .001). SOD was anticlastogenic in the same system at concentrations of 30 cytochrome C units/ml (approximately 10 micrograms/ml). Preliminary results obtained in a small series of liquidators showed regression or complete disappearance of CFs in the plasma after 2 months of treatment with EGb 761 (3 x 40 mg/d).
致断裂因子（CFs）最早在因意外或治疗原因接受辐射的人员血液中被发现。我们实验室的研究表明，在以氧化应激为特征的其他情况下也会出现CFs，并且超氧化物歧化酶（SOD）能够有效预防CFs诱导的染色体损伤。最近，我们在切尔诺贝利反应堆事故的大量救援人员中发现了CFs。这些清理人员属于高危人群，可能会从抗氧化剂的癌症化学预防中受益。然而，SOD必须通过注射给药，且不适用于长期预防性治疗。因此，在本研究中，我们评估了银杏叶提取物EGb 761的抗致断裂作用，该提取物以其超氧化物清除特性而闻名。EGb 761在健康供体经CF处理的血液培养物上进行了测试。在用健康志愿者全血辐照产生的CFs确定最佳保护EGb浓度后，该提取物在暴露于清理人员血浆中CFs的培养物上进行了测试。最终浓度为100微克/毫升时，抗致断裂作用得到证实。在连续12次实验中，CFs平均诱导18.00±4.41个畸变/100个细胞。在接受100微克/毫升EGb 761的平行培养物中，这一数字降至7.33±3.08（p<0.001）。在同一系统中，浓度为30个细胞色素C单位/毫升（约10微克/毫升）的SOD具有抗致断裂作用。在一小部分清理人员中获得的初步结果显示，用EGb 761（3×40毫克/天）治疗2个月后，血浆中的CFs减少或完全消失。
