Fraker P J, King L E, Laakko T, Vollmer T L
Department of Biochemistry, Michigan State University, East Lansing, MI 48824, USA.
J Nutr. 2000 May;130(5S Suppl):1399S-406S. doi: 10.1093/jn/130.5.1399S.
The results of more than three decades of work indicate that zinc deficiency rapidly diminishes antibody- and cell-mediated responses in both humans and animals. The moderate deficiencies in zinc noted in sickle cell anemia, renal disease, chronic gastrointestinal disorders and acrodermatitis enteropathica; subjects with human immunodeficiency virus; children with diarrhea; and elderly persons can greatly alter host defense systems, leading to increases in opportunistic infections and mortality rates. Conversely, short periods of zinc supplementation substantially improve immune defense in individuals with these diseases. Mouse models demonstrate that 30 d of suboptimal intake of zinc can lead to 30-80% losses in defense capacity. Collectively, the data clearly demonstrate that immune integrity is tightly linked to zinc status. Lymphopenia and thymic atrophy, which were the early hallmarks of zinc deficiency, are now known to be due to high losses of precursor T and B cells in the bone marrow. This ultimately leads to lymphopenia or a failure to replenish the lymphocytic system. Glucocorticoid-mediated apoptosis induced by zinc deficiency causes down-regulation of lymphopoiesis. Indeed, zinc itself can modulate death processes in precursor lymphocytes. Finally, there is substantial evidence that zinc supplementation may well reduce the impact of many of the aforementioned diseases by preventing the dismantling of the immune system. The latter represents an important area for research.
三十多年的研究结果表明，锌缺乏会迅速削弱人类和动物体内抗体介导和细胞介导的免疫反应。镰状细胞贫血、肾脏疾病、慢性胃肠疾病和肠病性肢端皮炎患者；感染人类免疫缺陷病毒的人群；腹泻儿童；以及老年人中存在的中度锌缺乏，会极大地改变宿主防御系统，导致机会性感染增加和死亡率上升。相反，短期补充锌能显著改善患有这些疾病的个体的免疫防御能力。小鼠模型表明，30天摄入不足的锌可导致防御能力损失30%-80%。总体而言，这些数据清楚地表明免疫完整性与锌状态密切相关。淋巴细胞减少和胸腺萎缩是锌缺乏的早期特征，现在已知这是由于骨髓中前体T细胞和B细胞大量损失所致。这最终导致淋巴细胞减少或淋巴细胞系统无法补充。锌缺乏诱导的糖皮质激素介导的细胞凋亡导致淋巴细胞生成下调。事实上，锌本身可以调节前体淋巴细胞的死亡过程。最后，有大量证据表明，补充锌很可能通过防止免疫系统的破坏来减轻上述许多疾病的影响。后者是一个重要的研究领域。
