聚碳酸酯、聚乙烯微塑料对小鼠小肠结构与屏障基因的影响

Effects of polycarbonate and polyethylene microplastics on intestinal structure and barrier genes in mice

中文关键词:  微塑料  聚碳酸酯  聚乙烯  小鼠  小肠结构  肠道屏障基因

英文关键词:microplastic  polycarbonate  polyethylene  mice  intestine structure  intestinal barrier gene

中文摘要:

      目的 探究食源性微塑料聚碳酸酯(polycarbonate, PC)、聚乙烯(polythylene, PE)对小鼠小肠结构、肠道屏障基因表达的影响。方法 4周龄的小鼠分为正常饮食组(对照组), 高浓度PE (30 g/kg鼠粮)添加组(HPE组), 高浓度PC (30 g/kg鼠粮)添加组(HPC组), 低浓度PE (3 g/kg鼠粮)添加组(LPE组), 低浓度PC (3 g/kg鼠粮)添加组(LPC组), 饲喂4周。剖检, 采集小鼠十二指肠、空肠、回肠制作石蜡切片, 观察微塑料对小肠显微结构的影响。定量聚合酶链反应法测定小鼠各肠段屏障基因相对表达量。结果 相比于对照组, 实验组的小鼠普遍绒毛高度降低、表面积减小, 隐窝深度增加, 绒毛高度与隐窝深度的比值变小, 结果呈剂量依赖的关系。与PC组相比, PE组对小肠的显微结构影响更显著。PC、PE会使小鼠十二指肠、回肠屏障基因Claudin-1、Claudin-2、Claudin-7的表达量大部分下调, 而小鼠空肠屏障基因Claudin-1、Claudin-2、Claudin-7、Claudin-15、Zone occludens 1 (ZO-1)的表达量大部分上调。PC、PE微塑料使十二指肠、空肠、回肠屏障基因Occludin表达量大部分都上调。结论 PC、PE损伤了小鼠小肠显微结构, 改变了肠道屏障基因的表达, 调节肠道屏障功能。

英文摘要:

      Objective To investigate the effects of foodborne microplastics polycarbonate (PC) and polyethylene (PE) on intestinal structure barrier gene expression in mice. Methods The 4-week-old mice were divided into normal diet group (control group), high concentration PE (30 g/kg chow) microplastic diet group (HPE group), high concentration PC (30 g/kg chow) microplastic diet group (HPC group), low concentration PE (3 g/kg chow) microplastic diet group (LPE group) and low concentration PE (3 g/kg chow) microplastic diet group (LPC group). After 4 weeks, duodenum, jejunum and ileum segments of mice in each group were collected for paraffin section to observe the effects of microplastics on the intestinal microstructure of mice. The relative expression of intestinal barrier gene in mice was determined by quantitative polymerase chain reaction. Results Compared with the control group, the villus height and surface area of the experimental group decreased, the crypt depth increased, and the ratio of villus height to crypt depth decreased, and the results showed a dose-dependent relationship. Compared with PC group, PE group had more significant effect on the microstructure of small intestine. PC and PE could reduce the expression levels of duodenal and ileum barrier genes Claudin-1, Claudin-2 and Claudin-7 in mice. However, the expression of jejunum barrier genes Claudin-1, Claudin-2, Claudin-7, Claudin-15 and Zone occludens 1 (ZO-1) were mostly up-regulated. Most of the Occludin expression of duodenum, jejunum and ileum barrier gene was up-regulated by PC and PE microplastics. Conclusion PC and PE microplastics can change the microstructure of small intestine and the expression of intestinal barrier gene in mice, and regulate the function of intestinal barrier.