低剂量氢醌诱导hPARP-1蛋白正常及缺陷细胞适应性反应研究

目的观察人胚胎肺成纤维细胞（HLF）正常及缺陷细胞在低剂量氢醌（hydroquinone，HQ）处理后能否诱导适应性反应，探讨PARP-1蛋白缺陷与正常细胞诱导适应性反应与微核形成及细胞周期变化的关系，进一步阐明适应性反应形成机制。方法用低剂量HQ预处理细胞后，观察细胞和DNA对大剂量HQ攻击的适应性反应，从微核率及核异常率、细胞周期等方面测定细胞变化情况。结果在细胞整体活力水平，0．001～0．050μmol／L HQ预处理可以提高细胞对攻击剂量80．0μmol／L的耐受性；HLF、转染绿色荧光蛋白真核表达载体的HLF（HLFC）和转染hPARP-1基因反义RNA真核表达载体的HLF（HLFP）细胞经HQ低剂量预处理及大剂量攻击后，各剂量组不同程度出现含微核和核异常细胞，G1、G2、S期细胞数分布均不相同。与同种细胞仅大剂量攻击比较，0—0．050μmol／L HQ预处理的HLF，HLFC及HLFP细胞微核率及核异常率差异均有统计学意义（P〈0．05）。HQ预处理的HLF和HLFC细胞均出现G2期阻滞；HLFP细胞表现为G2期阻滞，1．000、2．000μmnol／L出现G1期阻滞。结论在低剂量HQ作用下，hPARP-1蛋白缺陷细胞和正常细胞一样有适应性反应，但低于正常细胞，说明hPARP-1蛋白在细胞适应性反应方面起重要作用，适应性反应与细胞周期调控等有关。

Low concentration of hydropuinone-induced adaptive response in h-PARP-1 protein normal and deficient cells

OBJECTIVE: To investigate whether or not adaptive response of hPARP-1 protein normal and deficient cells is induced by low dose of hydroquinone (HQ), and to analyze the relationship between the adaptive response and micronuclei formation, and cell cycle alteration in human embryo lung fibroblasts (HLF), so as to elucidate the mechanism of adaptivie response. METHODS: HLF, HLFC and HLFP cells pretreated with low concentration were retreated by high concentration of HQ. Cellular viability, the rate of micronuclei and abnormal nuclei, cell cycle and DNA strand break were determined. RESULTS: The tolerance to 80.0 micromol/L concentration of HQ was enhanced when HLF, HLFC and HLFP cells were pretreated with HQ from 0.001 - 0.050 micromol/L. There were varying degrees of micronuclei and abnormal nuclei in three cells pretreated with low concentration of HQ and then retreated with high concentration of HQ; the cell numbers of G1, G2, S phase in cell cycle were obviously different. When compared with only high attack dose, the micronuclei rate and abnormal nuclei rate of HLF, HLFC and HLFP decreased by pretreatment with HQ at high concentration (P < 0.05), meanwhile increased by pretreatment with HQ at low concentration (P < 0.05). HLF, HLFC and HLFP showed blockage in G2 phase when pretreated with HQ at 0 approximately 0.05 micromol/L, but HLFP showed blockage in G1 phase, and in S phase at 1.0 and 2.0 micromol/L. CONCLUSION: The level of adaptive response of hPARP-1 protein deficient cells was lower than normal cell, suggesting that hPARP-1 protein may play an important role in the adaptive response of cells, which may be related with the regulation of cell cycle.