甲醛和甲醇染毒对小鼠和离体培养细胞毒性的比较研究

发布时间：2018-02-25 08:43

本文关键词： 甲醛甲醇联合染毒氧化损伤　出处：《华中师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：甲醛(Formaldehyde,FA)是常见的室内空气污染物。室内甲醛污染可对神经系统、生殖系统、免疫系统等产生毒性。2014年,美国国家研究理事会明确指出甲醛污染可以导致人类患白血病,但是关于甲醛致白血病的机理尚不清楚。为了解甲醛致白血病的机理,本文从甲醛分子结构出发,以小鼠和离体培养细胞为研究对象,探究甲醛毒性机制,为研究甲醛致白血病的分子机理提供科学依据。本研究首先选用72只SPF级雄性昆明鼠为受试动物,随机分为六组,采用灌胃的方式暴露染毒。第一组为生理盐水对照组,第二组为甲醛40mg/kg组,第三组为甲醇40 mg/kg,第四组为甲醛10 mg/kg+甲醇30 mg/kg,第五组为甲醛20 mg/kg+甲醇20 mg/kg,第六组为甲醛30 mg/kg+甲醇10 mg/kg,连续灌胃七天。染毒结束后,将小鼠麻醉,心脏取血后处死,取小鼠的肝脏,血液,骨髓细胞,分别检测小鼠的氧化应激水平(活性氧、丙二醛、谷胱甘肽含量)、甲醛含量、甲醛脱氢酶的相对表达量。结果显示:与对照组相比,实验组的氧化损伤显著增加;与甲醛10 mg/kg+甲醇30 mg/kg组相比,甲醛30 mg/kg+甲醇10 mg/kg组小鼠肝脏ROS的含量出现显著下降(p0.05),肝脏MDA存在极显著下降(p0.01),肝脏GSH存在极显著升高(p0.01),因此在联合染毒组中,随着甲醛浓度的增加,甲醇浓度的减少,氧化损伤水平有上升的趋势;实验用 AHMT(4-amino-3-hydrazine-5-mercaP to-1,2,4-triazole)法测定甲醛的含量,与空白组相比,血液和骨髓中甲醛含量均无显著差异性;采用RT-PCR法,检测血液和骨髓中甲醛脱氢酶相对表达量,与空白组相比,各染毒组中甲醛脱氢酶的相对表达量显著增加;甲醛40 mg/kg染毒组与甲醇40 mg/kg染毒组甲醛脱氢酶的表达量有显著差异(p0.01);与FA30 mg/kg+MeOH 10 mg/kg相比,FA 10 mg/kg+MeOH 30 mg/kg组中甲醛脱氢酶的表达量极显著上升(p0.01),联合染毒组中甲醛脱氢酶的含量随着甲醛的增加、甲醇的减少而表现出上升的趋势。本研究表明,N_2a细胞经不同浓度的甲醛和甲醇染毒12h后,单独染毒组中:低浓度的甲醛/甲醇促进细胞的生长,高浓度的甲醛/甲醇抑制细胞的生长,细胞内ROS含量与甲醛/甲醇的浓度呈线性相关,与空白组相比,细胞内甲醛和甲醇含量显著升高,24h修复后都恢复到正常水平。联合染毒组中:随着甲醛浓度的增加,细胞活力下降,ROS含量增加,细胞内甲醛含量增加,修复后会到正常水平。与甲醛175μmol/L组相比,甲醇175μmol/L组中FDH相对表达量极显著下降,联合染毒组中随着甲醛浓度的增加,细胞内FDH的表达量增加。研究表明,甲醛和甲醇的毒性不一致,甲醛毒性机制可能存在其它方式。
[Abstract]:Formaldehyde is a common indoor air pollutant. Indoor formaldehyde pollution can cause toxicity to nervous system, reproductive system, immune system and so on. In 2014, the National Research Council of the United States clearly pointed out that formaldehyde pollution can lead to human leukemia. However, the mechanism of formaldehyde-induced leukemia is not clear. In order to understand the mechanism of formaldehyde-induced leukemia, this paper studies the mechanism of formaldehyde toxicity from the molecular structure of formaldehyde, taking mice and cultured cells in vitro as research objects. In order to provide scientific basis for studying the molecular mechanism of formaldehyde-induced leukemia, 72 male Kunming mice of SPF grade were randomly divided into six groups. The second group was formaldehyde 40 mg / kg group, the third group was methanol 40 mg / kg, the 4th group was formaldehyde 10 mg/kg methanol 30 mg / kg, 5th group was formaldehyde 20 mg/kg methanol 20 mg / kg, 6th group was formaldehyde 30 mg/kg methanol 10 mg / kg. The liver, blood and bone marrow cells of the mice were taken and the oxidative stress levels (reactive oxygen species, malondialdehyde, glutathione content, formaldehyde content) were measured. The relative expression of formaldehyde dehydrogenase. The results showed that the oxidative damage was significantly increased in the experimental group compared with the control group, and compared with the formaldehyde 10 mg/kg methanol 30 mg/kg group. In the 30 mg/kg methanol 10 mg/kg group, the content of ROS in liver, MDA in liver and GSH in liver were significantly decreased, respectively. Therefore, the concentration of methanol decreased with the increase of formaldehyde concentration in the combined exposure group. The content of formaldehyde in blood and bone marrow was not significantly different from that in blank group, and the relative expression of formaldehyde dehydrogenase in blood and bone marrow was detected by RT-PCR method. Compared with the blank group, the relative expression of formaldehyde dehydrogenase in each exposed group was significantly increased. There was significant difference in the expression of formaldehyde dehydrogenase between the 40 mg/kg group and the methanol 40 mg/kg group, the expression of formaldehyde dehydrogenase in the FA10 mg/kg MeOH 30 mg/kg group was significantly higher than that in the FA30 mg/kg MeOH 10 mg/kg group, and the formaldehyde dehydrogenase level in the combined group was significantly higher than that in the FA30 mg/kg MeOH 10 mg/kg MeOH 30 mg/kg group, while in the combined treatment group the formaldehyde dehydrogenase expression level was significantly higher than that in the FA30 mg/kg MeOH 10 mg/kg group. The content of hydrogenase increases with the increase of formaldehyde, The decrease of methanol showed an increasing trend. This study showed that the cells were exposed to different concentrations of formaldehyde and methanol for 12 h, and the low concentration of formaldehyde / methanol promoted the growth of the cells. High concentration of formaldehyde / methanol inhibited the growth of cells. The content of ROS in the cells was linearly correlated with the concentration of formaldehyde / methanol, compared with the blank group. The contents of formaldehyde and methanol in the cells increased significantly and recovered to normal level after 24 hours of repair. In the combined exposure group, with the increase of formaldehyde concentration, the cell viability decreased and the content of Ros increased, while the content of formaldehyde in the cells increased. Compared with formaldehyde 175 渭 mol/L group, the relative expression of FDH in methanol 175 渭 mol/L group was significantly decreased, while in combined exposure group, the expression of FDH in cells increased with the increase of formaldehyde concentration. The toxicity of formaldehyde is not consistent with that of methanol, and the mechanism of formaldehyde toxicity may exist in other ways.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R114

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