纳米羟基磷灰石颗粒对巨噬细胞DNA的损伤  

Hydroxyapatite nanoparticles induce DNA damage in macrophages

作　　者：孙皎[1] 丁婷婷[1] 

机构地区：[1]上海交通大学医学院附属第九人民医院/上海生物材料研究测试中心,上海市200023

出　　处：《中国组织工程研究与临床康复》2008年第1期15-18,共4页Journal of Clinical Rehabilitative Tissue Engineering Research

基　　金：国家自然科学基金项目(30470479);上海市重点(特色)学科项目(T0202);上海市科委项目(0752nm026)~~

摘　　要：目的:纳米颗粒由于其特殊的尺寸效应,会对细胞内处于纳米尺寸级的RNA、DNA和蛋白质等生物大分子直接产生不良影响,使生物体受到损害。因此,从分子水平上探讨纳米羟基磷灰石颗粒对细胞DNA损伤的相关基因或蛋白的影响具有重要的科学意义。方法:实验于2005-12/2006-12在上海生物材料研究测试中心完成。①实验材料:纳米羟基磷灰石颗粒由中科院上海硅酸盐所提供,粒径大小为30～80nm。300W/40kHz的超声条件下,用含体积分数为0.1小牛血清的RPMI-1640振荡纳米颗粒,制备成终浓度为1g/L的悬浮液,4℃保存1周。②实验方法:选用RT-PCR的技术,通过原代培养大鼠腹腔巨噬细胞,在分子水平上检测纳米羟基磷灰石颗粒对DNA损伤通路中P53、P21、gadd45以及HSP70这些关键蛋白转录水平的影响。结果:通过mRNA水平的检测,发现P53、P21及HSP70的表达均随着纳米羟基磷灰石颗粒浓度的增加而升高,并在100mg/L条件下P53、P21及HSP70有显著性表达(P<0.05),而当纳米羟基磷灰石颗粒达到200mg/L,只有P21的表达反而有所降低,同时各浓度的纳米羟基磷灰石颗粒对gadd45表达无明显影响(P>0.05)。结论:实验证实了100mg/L纳米羟基磷灰石颗粒可以引起DNA的明显损伤。并且当纳米羟基磷灰石颗粒浓度达到200mg/L时,受损的DNA已不易被修复。同时,P53和HSP70可成为评价纳米羟基磷灰石颗粒安全性较为灵敏的指标。AIM： Nanoparticles with its special size effects have bad impacts on RNA, DNA and protein. This article investigates the influence of hydroxyapatite nanoparticles on DNA damage in a molecular level. METHODS： Experiments were pertformed at the Shanghai Biomaterials Research ＆ Testing Center from December 2005 to December 2006. （l^Hydroxyapatite nanopartieles were offered by Shanghai Institute of Ceramic Chinese Academy of Sciences. Diameter of the particles was 30-80 nm. RPMI-1640 nanoparticles containing 0.1 bovine blood serum was used to prepare 1 g/L suspension at 4 ℃ for I week under 300 W/40 kHz ultrasound. （2）Influence of hydroxyapatite nanoparticles on P53, P21, gadd45 and HSP70 of rat peritoneal maerophages in the DNA damage pathway was determined by RT-PCR. RESULTS： The results showed that P53, P21 and HSP70 would express increased with the concentrations of hydroxyapatite nanoparticles. The expression of P53, P21 and HSPT0 had obvious difference at 100 mg/L of hydroxyapatite nanoparticles （P 〈 0.05）, but P21 expressed reduced when concentration of hydroxyapatite nanoparticles was 200 mg/L. Hydroxyapatite nanoparticles had no effects on gadd45 （P 〉 0.05）. CONCLUSION： 100 mg/L hydroxyapatite nanopartieles induces the obvious DNA damage. DNA damage is irreversible when the concentration of these nanoparticles is more than 200 mg/L. Both P53 and HSP70 are sensitive indexes to evaluate hydroxyapatite nanoparticles.

关 键 词：纳米颗粒 羟基磷灰石 DNA损伤 反转录-聚合酶链反应 

分 类 号：R318.08[医药卫生—生物医学工程]