Brown D M, Stone V, Findlay P, MacNee W, Donaldson K
School of Life Sciences, Napier University, 10 Colinton Road, Edinburgh EH10 5DT, UK.
Occup Environ Med. 2000 Oct;57(10):685-91. doi: 10.1136/oem.57.10.685.
Particulate air pollution has been shown to cause adverse health effects, and the ultrafine particle component has been implicated. The aim of the present study was to investigate whether an ultrafine particle exerted its effects through transition metals or other soluble factors released from the surface of the particles.
Both in vitro and in vivo models were used to test the imflammogenicity of carbon black (CB) and ultrafine carbon black (UfCB) and the role of transition metals was investigated by treating the particles with desferrioxamine mesylate (desferal), a transition metal chelator. Rats were instilled with particles and the cell population assessed by bronchoalveolar lavage (BAL). Calcium homeostasis in macrophages was assessed with a fluorimetric technique.
UfCB was inflammogenic compared with CB when instilled into Wistar rat lungs, an effect which could not be ameliorated by desferal treatment of the particles. Particle leachates produced no significant inflammation in vivo. In vitro experiments showed that the cytosolic calcium ion concentration in Mono Mac 6 cells was increased significantly after UfCB treatment and treatment of particles with desferal did not alter these effects. Particle leachates had no effect on cytosolic calcium ion concentration. Iron was not detected in leachates of the particles with the desferal assay, however, ng/mg of particles were detectable in citrate leachates with inductively coupled plasma-mass spectrometry (ICP-MS).
The increased inflammogenicity of UfCB compared with CB cannot be explained by soluble transition metals released from or by accumulation of iron at the particle surface. Differences may be accounted for by increased surface area or particle number.
已证明颗粒物空气污染会对健康产生不利影响，其中超细颗粒成分被认为与此有关。本研究的目的是调查超细颗粒是否通过从颗粒表面释放的过渡金属或其他可溶性因子发挥其作用。
使用体外和体内模型来测试炭黑（CB）和超细炭黑（UfCB）的致炎作用，并通过用过渡金属螯合剂甲磺酸去铁胺（去铁敏）处理颗粒来研究过渡金属的作用。给大鼠滴注颗粒，并通过支气管肺泡灌洗（BAL）评估细胞群体。用荧光技术评估巨噬细胞中的钙稳态。
当将UfCB滴注到Wistar大鼠肺中时，与CB相比具有致炎作用，颗粒经去铁敏处理后这种作用无法得到改善。颗粒浸出液在体内未产生明显炎症。体外实验表明，UfCB处理后Mono Mac 6细胞中的胞质钙离子浓度显著增加，用去铁敏处理颗粒并未改变这些作用。颗粒浸出液对胞质钙离子浓度没有影响。用去铁敏测定法在颗粒浸出液中未检测到铁，然而，用感应耦合等离子体质谱法（ICP-MS）在柠檬酸盐浸出液中可检测到每毫克颗粒中含纳克级的铁。
与CB相比，UfCB致炎作用增强不能用从颗粒表面释放的可溶性过渡金属或颗粒表面铁的积累来解释。差异可能是由于表面积增加或颗粒数量增多所致。
