Iancu T C
Department of Pediatrics, Carmel Hospital, Haifa, Israel.
Pediatr Pathol. 1990;10(1-2):281-96. doi: 10.3109/15513819009067114.
The morphologic aspects of iron overload have been studied in human subjects, mammals, and birds with spontaneous overload, in a variety of experimental animals, and also in cell cultures. Reviewed here are the contributions of electron microscopy to the understanding of the iron-loading process, as reported during the last 12 years. The electron-density of ferrihydrite cores located within the protein shell of the ferritin molecule enabled its identification within either cytosol or lysosomes (siderosomes) of iron-exposed cells. The process of (holo)ferritin assembly, its transfer into siderosomes, and its degradation to hemosiderin can be followed in various cells. Siderosomes display cell-line-specific ultrastructural features, and different cell types show varying iron-segregating capacity. The study of experimental animals and cultured cells show that an iron-rich milieu may be damaging, probably through iron-catalyzed lipid peroxidation. Recent ultrastructural studies stress the value of describing initial alterations as opposed to the irrelevant end-stage findings. Further efforts should be directed toward elucidating the origin of iron in neonatal hemochromatosis, the role of iron in infection and neoplasia, and the nature and role of brain iron.
人们已经在患有自发性铁过载的人类受试者、哺乳动物和鸟类、各种实验动物以及细胞培养物中研究了铁过载的形态学方面。本文回顾了过去12年期间报道的电子显微镜在理解铁负载过程中的贡献。位于铁蛋白分子蛋白质壳内的水铁矿核心的电子密度使其能够在铁暴露细胞的胞质溶胶或溶酶体（铁体）中被识别。（全）铁蛋白组装过程、其向铁体的转移以及其降解为含铁血黄素的过程可以在各种细胞中追踪。铁体显示出细胞系特异性的超微结构特征，并且不同细胞类型表现出不同的铁分离能力。对实验动物和培养细胞的研究表明，富含铁的环境可能具有损害作用，可能是通过铁催化的脂质过氧化作用。最近的超微结构研究强调了描述初始改变而非无关的终末期发现的价值。应进一步努力阐明新生儿血色素沉着症中铁的来源、铁在感染和肿瘤形成中的作用以及脑铁的性质和作用。
