微塑料暴露对小鼠学习记忆的影响及其作用机制

姜新泽; 刘强; 孙旭; 侯姜姗; 马瑞; 程梅; 吴玉龙

doi:10.16098/j.issn.0529-1356.2024.05.004

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解剖学报 ›› 2024, Vol. 55 ›› Issue (5) : 541-546. DOI: 10.16098/j.issn.0529-1356.2024.05.004

神经生物学

微塑料暴露对小鼠学习记忆的影响及其作用机制

姜新泽¹ 刘强² 孙旭³ 侯姜姗¹ 马瑞³ 程梅^3* 吴玉龙^1*

作者信息 +

Effects of microplastics exposure on learning and memory in mice and its mechanism

JIANG Xin-ze¹ LIU Qiang² SUN Xu³ HOU Jiang-shan¹ MA Rui³ CHENG Mei^3* WU Yu-long^1* #br#

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文章历史 +

摘要

目的探讨微塑料（MPs）暴露对小鼠学习记忆的影响，观察MPs暴露对脑源性神经营养因子（BDNF）/酪氨酸激酶受体B（TrkB）/N-甲基-D-天冬氨酸受体2B亚基（NR2B）信号通路蛋白表达和神经发生的影响，探索MPs暴露对小鼠学习记忆影响的作用机制。方法 40只雄性C57BL/6小鼠随机分为对照组（Ctrl）和微塑料暴露组（MPs），MPs组小鼠以微塑料200 μl ［0.3 mg/(kg·d）］连续30 d灌胃。Morris水迷宫实验检测小鼠学习记忆能力；Western blotting检测小鼠海马BDNF、TrkB和NR2B蛋白水平；免疫荧光染色观察小鼠海马区双皮质素（DCX）和神经元核抗原（NeuN）阳性细胞数量，评估海马神经发生。结果与对照组小鼠相比，MPs暴露组小鼠学习记忆能力显著降低（P<0.01），海马BDNF、TrkB和NR2B表达也显著低于对照组（P<0.05）。MPs组小鼠海马DCX和NeuN阳性细胞数量显著低于对照组（P<0.01）。结论 MPs暴露引起的学习记忆损伤可能与抑制BDNF/TrkB/NR2B信号通路，减少海马神经发生有关。

Abstract

Objective To investigate the effect of microplastic (MPs) exposure on learning and memory in mice, and its mechanism by observing the protein expression of brain-derived neurotrophic factor (BDNF) /tyrosine receptor kinase B (TrkB) /N-methyl-D-aspartate receptor subtype 2B (NR2B) signaling pathway and neurogenesis. Methods Forty male C57BL/6 mice were randomly divided into control group (Ctrl) and microplastics exposure group (MPs). Mice in MPs group were treated with 0.3 mg/(kg·d) microplastics, administered by gavage at a volume of 200 μl for 30 consecutive days. Morris water maze test was used to evaluate the spatial learning and memory ability of mice. Western blotting was used to detect the protein levels of BDNF, TrkB and NR2B in hippocampus of mice. Immunofluorescent staining was used to observe the number of doublecortin (DCX) and neuronal nuclei antigen (NeuN) positive cells in the hippocampus of mice to evaluate hippocampal neurogenesis. Results Compared with the control group, the ability of learning and memory decreased significantly in MPs group mice (P<0.01). The expression levels of BDNF, TrkB and NR2B in the hippocampus of MPs group mice were significantly lower than those of control group (P<0.05). The number of DCX and NeuN positive cells in the hippocampus of MPs group was significantly lower than that of control group (P<0.01). Conclusion MPs exposure induces learning and memory impairment which may be related to inhibiting BDNF/TrkB/NR2B signaling pathway and reducing hippocampal neurogenesis.

导出引用

姜新泽刘强孙旭侯姜姗马瑞程梅吴玉龙. 微塑料暴露对小鼠学习记忆的影响及其作用机制[J]. 解剖学报. 2024, 55(5): 541-546 https://doi.org/10.16098/j.issn.0529-1356.2024.05.004

JIANG Xin-ze LIU Qiang SUN Xu HOU Jiang-shan MA Rui CHENG Mei WU Yulong. Effects of microplastics exposure on learning and memory in mice and its mechanism[J]. Acta Anatomica Sinica. 2024, 55(5): 541-546 https://doi.org/10.16098/j.issn.0529-1356.2024.05.004

中图分类号： R74

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