慢性低剂量钴暴露对人大脑类器官的神经毒性研究

doi:10.3969/j.issn.1004-616x.2025.05.001

摘要/Abstract

摘要： 目的：研究慢性钴暴露对人大脑类器官的神经毒性作用，为评估重金属钴的潜在健康风险提供实验依据。方法：将分化第28天的人诱导多能干细胞(iPSC)源性大脑类器官随机分为对照组和5、10、20 μmol/L CoCl₂暴露组，持续染毒28 d。于第56天收取人大脑类器官样本，采用免疫荧光染色法表征人大脑类器官分化状态(SOX2/TBR2/CTIP2/TUJ1/NeuN/SYN1)、缺氧诱导因子-1α(HIF-1α)的表达水平、细胞缺氧状态(Hypoxyprobe)、增殖与凋亡水平(Ki-67/TUNEL)以及星形胶质细胞损伤情况(GFAP)。结果：第56天的人大脑皮质类器官维持较高增殖活性，神经祖细胞自组织形成脑室区样结构，与中间祖细胞和皮质深层神经元共同形成与人类大脑相似的层状结构。与对照组相比，慢性钴暴露上调HIF-1α蛋白表达(P<0.01)，缺氧细胞增多；TUNEL阳性凋亡细胞增加(P<0.01)，且富集于中间祖细胞和神经元的分布区域；明场动态监测显示10、20 μmol/L钴暴露组脑室区结构进行性消失；对星形胶质细胞的表征发现，慢性钴暴露组GFAP荧光信号明显减弱。结论：慢性钴暴露通过稳定HIF-1α诱导细胞假性缺氧，导致神经细胞凋亡增加、脑室区结构崩塌和星形胶质细胞损伤。

关键词: 钴, 人大脑类器官, 缺氧诱导因子-1α, 神经毒性

Abstract: OBJECTIVE：To investigate neurotoxic effects of chronic cobalt exposure on human cerebral organoids and to provide experimental evidence for assessing potential health risks of heavy metal cobalt. METHODS：Human iPSC-derived cerebral organoids at day 28 of differentiation were randomly divided into the control group， 5， 10， and 20 μmol/L CoCl₂ exposure groups， with continuous exposure for 28 days. Samples of human cerebral organoids were collected on day 56. Immunofluorescence staining was used to systematically characterize the differentiation status (SOX2/TBR2/CTIP2/TUJ1/NeuN/SYN1)，expression of hypoxia-inducible factor-1α，cellular hypoxia status (Hypoxyprobe)，proliferation and apoptosis levels (Ki-67/TUNEL)， and astrocyte damage (GFAP) of human cerebral organoids.RESULTS： Day56 organoids maintained high proliferative activity. Neural progenitor cells self-organized into ventricular zone-like structures， forming physiological lamellar architectures with intermediate progenitors and deep-layer cortical neurons. Chronic cobalt exposure significantly upregulated HIF-1α protein expression (P<0.01) and increased hypoxic cells versus controls. TUNEL-positive apoptotic cells showed dose-dependent elevation (P<0.01)，predominantly localized in intermediate progenitor/neuron interface regions. Bright-field monitoring revealed progressive disintegration of ventricular zone structures in medium/high-dose groups. GFAP fluorescence intensity was markedly attenuated in exposure groups， indicating astrocyte impairment. CONCLUSION： Chronic cobalt exposure stabilizes HIF-1α to induce pseudohypoxia， leading to three neurotoxic outcomes： increased neuronal apoptosis，ventricular zone collapse，and astrocyte damage.

Key words: cobalt, human cerebral organoids, HIF-1α, neurotoxicity

中图分类号:

R3
R994.6

郭新华, 黄琰, 陈琪琪, 鲁诗雅, 曾品利, 王志秋, 李灏, 卜迁. 慢性低剂量钴暴露对人大脑类器官的神经毒性研究[J]. 癌变·畸变·突变, 2025, 37(5): 345-352.

GUO Xinhua, HUANG Yan, CHEN Qiqi, LU Shiya, ZENG Pinli, WANG Zhiqiu, LI Hao, BU Qian. Neurotoxicity of chronic low-dose cobalt exposure in human cerebral organoids[J]. Carcinogenesis, Teratogenesis & Mutagenesis, 2025, 37(5): 345-352.

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