Razzaboni B L, Bolsaitis P
Energy Laboratory, Massachusetts Institute of Technology, Cambridge 02139.
Environ Health Perspect. 1990 Jul;87:337-41. doi: 10.1289/ehp.9087337.
The formation of reactive oxygen species resulting from the interaction of silica dust particles with red blood cell membranes was investigated; particularly, the effect of surface hydroxyl (silanol) group concentration on the rate of formation of such reactive oxygen species was investigated. The rate of formation was measured indirectly through the effect of catalase, a hemoprotein peroxidase, on silica-induced hemolysis. It was found that the addition of exogenous catalase to erythrocytes markedly reduces the hemolysis caused by silica particles. Furthermore, the amount of catalase required for deactivation of silica per unit area of particle surface is lower for fumed silica particles and calcined crystalline particles than for uncalcined, crystalline silica, suggesting a correlation between the concentration of OH groups at the silica particle surface and its potential for generation of H2O2. The addition of albumin, a copper chelator, also decreases hemolysis. These results suggest that the hemolysis caused by silica particles is at least partly related to the formation of H2O2 at the particle surface and its subsequent reaction with Cu+ ions. The relationship between the concentration of surface silanol groups on the silica surface and the amount of catalase required to decrease hemolysis may also provide a method for testing potential fibrogenicity of respirable dusts.
研究了二氧化硅粉尘颗粒与红细胞膜相互作用产生活性氧物种的过程；特别地，研究了表面羟基（硅醇）基团浓度对这类活性氧物种形成速率的影响。通过过氧化氢酶（一种血红素蛋白过氧化物酶）对二氧化硅诱导的溶血作用的影响来间接测量形成速率。发现向红细胞中添加外源性过氧化氢酶可显著降低二氧化硅颗粒引起的溶血。此外，对于气相二氧化硅颗粒和煅烧结晶颗粒，使单位颗粒表面积的二氧化硅失活所需的过氧化氢酶量低于未煅烧的结晶二氧化硅，这表明二氧化硅颗粒表面的OH基团浓度与其产生H2O2的可能性之间存在相关性。添加白蛋白（一种铜螯合剂）也可减少溶血。这些结果表明，二氧化硅颗粒引起的溶血至少部分与颗粒表面H2O2的形成及其随后与Cu+离子的反应有关。二氧化硅表面硅醇基团浓度与降低溶血所需过氧化氢酶量之间的关系也可能提供一种测试可吸入粉尘潜在致纤维化性的方法。
