Intiyot Yaowarate, Kinouchi Takemi, Kataoka Keiko, Arimochi Hideki, Kuwahara Tomomi, Vinitketkumnuen Usanee, Ohnishi Yoshinari
Department of Bacteriology, University of Tokushima School of Medicine, Kuramoto-cho, Tokushima 770-8503, Japan.
J Med Invest. 2002 Feb;49(1-2):25-34.
An 80% ethanol extract of Murdannia loriformis, a Thai medicinal plant, was examined for antimutagenic activity and cancer chemopreventive activity. In the Salmonella mutation assay, the extract showed antimutagenicity against 2-amino-3-methylimidazo [4,5-f]quinoline, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, 2-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, 3-amino-1-methyl-5H-pyrido[4,3-b]indole, 2-amino-6-methyldipyrido [1,2-a:3',2'-d] imidazole, 2-aminodipyrido[1,2-a:3',2'-d]imidazole, 2-aminoanthracene, 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide, N-methyl-N'-nitro-N-nitrosoguanidine and methylazoxymethanol acetate and reduced their mutagenicities to 31.4-67.9% at the dose of 10 mg/plate. However, it did not inhibit the mutagenicities of 2-amino-9H-pyrido[2,3-b]indole, 2-amino-3-methyl-9 H-pyrido[2,3-b]indole, benzo[a]pyrene,N-ethyl-N'-nitro-N-nitrosoguanidine and 1-nitropyrene. The extract itself showed no mutagenicity. The chemopreventive activity of M. loriformis was examined using azoxymethane (AOM)-induced aberrant crypt focus (ACF) formation in the colon of F344 rats. The extract at doses of 0.1-1.0 g/kg wt significantly inhibited ACF formation in the initiation stage (21-51%), although it was more effective at a lower dose. In the post-initiation stage, the extract also tended to inhibit ACF formation (12-27%) and significantly decreased the number of larger ACFs that have more than 3 aberrant crypts per focus. The extract inhibited the formation of O6-methylguanine and N7-methylguanine in the colonic mucosa and muscular layers but not or increased in the liver. These results indicate that M. loriformis extract has antimutagenic activity toward various known mutagens and that it inhibits AOM-induced ACF formation both in the initiation and post-initiation stages in the rat colon.
对泰国药用植物阔苞水竹叶（Murdannia loriformis）的80%乙醇提取物进行了抗诱变活性和癌症化学预防活性研究。在沙门氏菌突变试验中，该提取物对2-氨基-3-甲基咪唑[4,5-f]喹啉、2-氨基-3,4-二甲基咪唑[4,5-f]喹啉、2-氨基-3,8-二甲基咪唑[4,5-f]喹喔啉、2-氨基-1-甲基-6-苯基咪唑[4,5-b]吡啶、2-氨基-1,4-二甲基-5H-吡啶并[4,3-b]吲哚、3-氨基-1-甲基-5H-吡啶并[4,3-b]吲哚、2-氨基-6-甲基二吡啶并[1,2-a:3',2'-d]咪唑、2-氨基二吡啶并[1,2-a:3',2'-d]咪唑、2-氨基蒽、2-(2-呋喃基)-3-(5-硝基-2-呋喃基)丙烯酰胺、N-甲基-N'-硝基-N-亚硝基胍和乙酸甲基偶氮甲醇显示出抗诱变活性，并在10 mg/平板的剂量下将它们的诱变性降低至31.4 - 67.9%。然而，它并未抑制2-氨基-9H-吡啶并[2,3-b]吲哚、2-氨基-3-甲基-9H-吡啶并[2,3-b]吲哚、苯并[a]芘、N-乙基-N'-硝基-N-亚硝基胍和1-硝基芘的诱变性。该提取物本身没有诱变性。使用偶氮甲烷（AOM）诱导F344大鼠结肠中异常隐窝灶（ACF）形成来检测阔苞水竹叶的化学预防活性。剂量为0.1 - 1.0 g/kg体重的提取物在起始阶段显著抑制ACF形成（21 - 51%），尽管在较低剂量时更有效。在起始后阶段，该提取物也倾向于抑制ACF形成（12 - 27%），并显著减少每个灶中具有超过3个异常隐窝的较大ACF的数量。该提取物抑制结肠黏膜和肌层中O6-甲基鸟嘌呤和N7-甲基鸟嘌呤的形成，但在肝脏中没有抑制作用或使其增加。这些结果表明，阔苞水竹叶提取物对多种已知诱变剂具有抗诱变活性，并且在大鼠结肠的起始和起始后阶段均抑制AOM诱导的ACF形成。
