Choi Yun Ju, Kim Ji Eun, Lee Su Jin, Gong Jeong Eun, Jin You Jeong, Seo Sungbaek, Lee Jae Ho, Hwang Dae Youn
Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute/Laboratory Animals Resources Center, Pusan National University, Miryang, South Korea.
Lab Anim Res. 2021 Nov 22;37(1):31. doi: 10.1186/s42826-021-00109-w.
The oral administration of polystyrene-microplastics (PS-MPs) causes chronic constipation of ICR mice, but there are no reports on their effects on the inflammatory response in the colon. To determine if the oral administration of MPs causes inflammation in the colon, the changes in the apoptosis-associated speck like protein containing a caspase recruitment domain (ASC)-inflammasome pathway, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway, and inflammatory cytokine expression were evaluated in the mid colon of ICR mice treated with 0.5 μm size PS-MPs for two weeks.
The thicknesses of the mucosa, muscle, flat luminal surface, and crypt layer were decreased significantly (p < 0.01) in the mid colon of the MPs treated group compared to the Vehicle treated group. On the other hand, a remarkable increase in the expression levels of NOD-like receptor pyrin domain-containing protein (NLRP) 3, ASC, and Cleaved Caspase (Cas)-1 protein was observed in the MPs treated group. In addition, similar increasing pattern in the levels of p-NF-κB and phospho-inhibitory subunit of NF-κB (p-IkB) α protein was detected. Four inflammatory cytokines, including NF-κB, interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β, showed an increased expression level after the MPs treatment.
Therefore, the present study suggests that PS-MPs can be a novel cause of an inflammatory response in the mid colon of ICR mice.
口服聚苯乙烯微塑料（PS-MPs）会导致ICR小鼠慢性便秘，但尚无关于其对结肠炎症反应影响的报道。为了确定口服微塑料是否会引发结肠炎症，我们评估了用0.5μm大小的PS-MPs处理两周的ICR小鼠结肠中部凋亡相关斑点样含半胱天冬酶募集结构域（ASC）炎性小体途径、活化B细胞核因子κB轻链增强子（NF-κB）信号通路以及炎性细胞因子表达的变化。
与载体处理组相比，微塑料处理组小鼠结肠中部的黏膜、肌肉、平坦管腔表面和隐窝层厚度显著降低（p < 0.01）。另一方面，在微塑料处理组中观察到含核苷酸结合寡聚化结构域样受体吡咯结构域蛋白（NLRP）3、ASC和裂解型半胱天冬酶（Cas）-1蛋白的表达水平显著增加。此外，还检测到p-NF-κB和NF-κB磷酸化抑制亚基（p-IκB）α蛋白水平呈现类似的增加模式。微塑料处理后，包括NF-κB、白细胞介素（IL）-6、肿瘤坏死因子（TNF）-α和IL-1β在内的四种炎性细胞因子表达水平升高。
因此，本研究表明PS-MPs可能是ICR小鼠结肠中部炎症反应的一个新诱因。
