邻苯二甲酸二(2-乙基己基)酯对秀丽线虫生殖能力的影响

Effect of di(2-ethylhexyl) phthalate on reproductive capacity of Caenorhabditis elegans

目的:探讨邻苯二甲酸二(2-乙基己基)酯(DEHP)对秀丽线虫生殖能力的影响。方法:设置对照组(K溶液)和DEHP低(0.1mg/L)、中(1.0 mg/L)、高(10.0 mg/L)3个剂量的染毒组,20℃下恒温培养染毒48 h,观察DEHP对秀丽线虫后代数目、世代时间以及瞬时产卵量的影响;利用二脒基苯基吲哚(DAPI)染色,观察并计数线虫有丝分裂区、减数分裂区的生殖细胞数;利用MD701突变株,在荧光显微镜下观察粗线期细胞的凋亡情况。结果:与对照组相比,L4期线虫暴露DEHP 48 h后,秀丽线虫的后代数目在1.0和10.0 mg/L剂量组显著下降(P<0.05),但对世代时间无明显影响(P>0.05)。随着DEHP暴露剂量的增加,线虫的瞬时产卵量下降(P<0.05)。与对照组相比,在DEHP 1.0和10.0 mg/L的暴露剂量下,秀丽线虫总生殖细胞数和有丝分裂区生殖细胞数均显著下降(P<0.01),在10.0 mg/L暴露剂量下减数分裂区生殖细胞显著减少(P<0.01)。随着染毒剂量的升高,粗线期生殖细胞凋亡数明显增加(P<0.01)。结论:DEHP可以导致秀丽线虫有丝分裂区增殖阻滞以及减数分裂区生殖细胞数减少,这种作用可能和DEHP导致秀丽线虫粗线期凋亡数目增多有关。

OBJECTIVE:To investigate the effect of di(2-ethylhexyl)phthalate(DEHP)on the reproductive capacity of nematode Caenorhabditis elegans(C.elegans).METHODS:C.elegans cultures were organized into several groups:control(K solution)and three DEHP exposure groups:low(0.1 mg/L),medium(1.0 mg/L)and high(10.0 mg/L).Reproductive capacities were evaluated based on brood size,generation time and egg-laying rate/h.Dianamidophenylindole(DAPI)staining was used to observe the number of germline cells in the mitotic zone and the meiotic region of nematodes.Using transgenic MD701 nematodes,apoptotic cells in the pachytene zone were observed with the aid of fluorescence microscopy.RESULTS:Compared with control group,brood sizes of C.elegans were significantly decreased in the 1.0 mg/L and 10.0 mg/L exposed groups(P<0.05),but had no significant effect on generation time(P>0.05).With the increase of exposure dose,the egg-laying rates were significantly decreased(P<0.01)and showed a dose-effect relationship.In addition,the total number of germline cells and the number of germline cells in the mitotic region were significantly decreased in the 1.0 mg/L(P<0.01)and 10.0 mg/L(P<0.01)exposed group.The number of germline cells in the meiotic region also showed a downward trend.Compared with the control group,the germline cell numbers in the meiotic region were decreased significantly at 10.0 mg/L exposure concentration group(P<0.01).With the increase of the dose,the germ cells showing apoptosis in the pachytene zone were also significantly increased(P<0.01).CONCLUSION:DEHP caused arrest in mitotic proliferation and reduction in the number of germ cells in the meiotic zone.The observed toxicity was related to the increased number of apoptosis caused by DEHP in the pachytene of C.elegans.