脑铁沉积、外周铁过载与认知功能障碍研究进展
Brain Iron Deposition, Body Iron Overload and Cognitive Impairment

多项研究发现脑铁沉积与认知功能障碍密切相关，但具体机制尚待明确。临床研究发现外周铁过载患者脑内存在脑铁异常沉积，与患者认知功能下降显著相关。组织病理学研究亦证实外周铁过载患者同时存在脑铁异常沉积。外周给予铁螯合剂可改善患者认知功能减退。综上，外周铁代谢紊乱被认为可能是脑铁沉积的原因之一，为脑铁代谢异常相关疾病的诊疗提供新思路。本文就脑铁沉积、外周铁代谢异常与认知功能损伤的相关性做一综述。

Increasing evidence indicates that brain iron deposition contributes to cognitive impairment, but the mechanism remains unclear. Clinical studies found increased brain iron accumulation significantly correlated with cognitive impairment. Histopathological studies confirmed that patients with body iron overload had increased brain iron accumulation. Several clinical trials showed systemic administration of iron chelation agent could slow the decline rate of cognitive function. Thus, systemic iron dysregulation was assumed as one contributor to brain iron accumulation. Herein, we reviewed the relationship of brain iron deposition, systemic iron status and associated cognitive impairment.

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