Peng Ke-Zheng, Zhang Song-Yan, Zhou Hong-Li
College of Chemical and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin 132022, China; College of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China.
Department of Laboratory, The General Hospital of China National Petroleum Corporation in Jilin, Jilin 132022, China.
J Ethnopharmacol. 2016 Nov 4;192:161-169. doi: 10.1016/j.jep.2016.07.012. Epub 2016 Jul 7.
Maydis stigma (corn silk) has a long history of use as a traditional herbal medicine or functional food in China and many other countries and has been listed in the Chinese Pharmacopea. However, little data about its potential toxicity is available.
In this study, we evaluated the subchronic toxicity and genotoxicity of the flavonoid-rich extract from Maydis stigma (FMS) in mice.
In the subchronic toxicity study, the FMS was administered orally to mice at doses of 2.50, 5.00 and 10.00g/kg/day for 28 consecutive days. At the end of experiment, general clinical signs, mortality, haematological, biochemical and histopathological parameters were examined. The genotoxicity of FMS was also evaluated by the micronucleus assay and the sperm malformation assay.
All animals survived until the scheduled necropsy, and no statistically significant or toxicologically relevant differences were observed in any of the FMS-treatment groups, compared with the control group. The no-observed-adverse-effect level (NOAEL) was determined as 10.00g/kg/day. Based on the results of the micronucleus assay and the sperm malformation assay, no evidence of genotoxicity was found either in somatic cells or germ cells even at an experimental upper limit dose (10.00g/kg/day).
The results of the present studies might support the safe use of FMS as a functional food, food additive and natural remedy.
玉米须在中国和许多其他国家作为传统草药或功能性食品有着悠久的使用历史，并已被列入《中国药典》。然而，关于其潜在毒性的数据却很少。
在本研究中，我们评估了玉米须富含黄酮提取物（FMS）对小鼠的亚慢性毒性和遗传毒性。
在亚慢性毒性研究中，将FMS以2.50、5.00和10.00g/kg/天的剂量连续28天口服给予小鼠。实验结束时，检查一般临床体征、死亡率、血液学、生化和组织病理学参数。还通过微核试验和精子畸形试验评估FMS的遗传毒性。
所有动物均存活至预定的尸检时间，与对照组相比，在任何FMS治疗组中均未观察到统计学上显著或毒理学相关的差异。未观察到有害作用水平（NOAEL）确定为10.00g/kg/天。基于微核试验和精子畸形试验的结果，即使在实验上限剂量（10.00g/kg/天）下，在体细胞或生殖细胞中也未发现遗传毒性的证据。
本研究结果可能支持FMS作为功能性食品、食品添加剂和天然药物的安全使用。
