2,2,4,7-Tetramethyl-1,2,3,4-tetrahydroquinoline (THQ) is a new synthetic compound with potential antioxidant activity. In this study, cytotoxic, genotoxic and antioxidant activities of THQ were studied on human lymphocytes with the use of the trypan blue exclusion assay, the TUNEL method, the comet assay and the micronucleus test. The activities of THQ were compared with those of a structurally similar compound-ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline, EQ), which is used in animal feeds as a preservative. Cytotoxic effects of THQ were observed after 1-h treatment at the concentration of 500 microM and after 24-h treatments at the concentrations of 250-500 microM. Although the micronucleus test did not reveal a genotoxic effect of THQ, in the comet assay the statistically significant increase in DNA damage was observed as compared with the control. On the other hand, the protection of human lymphocytes against DNA damage induced by hydrogen peroxide suggests an antioxidant activity of THQ. The comparative analysis of THQ and EQ activities performed in these studies revealed that THQ was less cytotoxic and less genotoxic than EQ. Slightly lower antioxidant activity of THQ was also shown in the comet assay when it was used at the lower studied doses (1-5 microM), but for the highest one (10 microM) its efficiency was similar to that of EQ. In the micronucleus assay THQ was more effective than EQ in protecting the cultured lymphocytes from clastogenicity of H2O2. We believe that THQ is worthy of further detailed studies on its antioxidant properties to confirm its usefulness as a preservative.

中文翻译：

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2,2,4,7-四甲基-1,2,3,4-四氢喹啉和乙氧基喹对人淋巴细胞的细胞毒性，遗传毒性和抗氧化作用的比较分析。

2,2,4,7-四甲基-1,2,3,4-四氢喹啉（THQ）是一种具有潜在抗氧化活性的新型合成化合物。在这项研究中，使用台盼蓝排除试验，TUNEL方法，彗星试验和微核试验研究了THQ对人淋巴细胞的细胞毒性，遗传毒性和抗氧化活性。将THQ的活性与结构相似的化合物-乙氧基喹（1,2-二氢-6-乙氧基-2,2,4-三甲基喹啉，EQ）进行了比较，该化合物在动物饲料中用作防腐剂。在浓度为500 microM的条件下处理1小时后，在浓度为250-500 microM的条件下处理24小时后，观察到THQ的细胞毒性作用。尽管微核试验未显示THQ的遗传毒性作用，在彗星试验中，与对照相比，观察到DNA损伤的统计学显着增加。另一方面，保护人类淋巴细胞免于过氧化氢引起的DNA损伤表明THQ具有抗氧化活性。在这些研究中进行的THQ和EQ活性的比较分析表明，THQ的细胞毒性和遗传毒性均低于EQ。当以较低的研究剂量（1-5 microM）使用THQ时，在彗星试验中也显示出较低的THQ抗氧化活性，但对于最高的抗氧化活性（10 microM），其效率与EQ相似。在微核试验中，THQ在保护培养的淋巴细胞免受H2O2的致死性方面比EQ更有效。