Zheng Jinfa, Wang Jinyu, Li Kun, Qin Xin, Li Sheng, Chang Xuhong, Sun Yingbiao
Department of Toxicology, School of Public Health, Lanzhou University, Lanzhou, China.
Institute of Anthropotomy and Histoembryology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China.
Environ Toxicol. 2023 Nov;38(11):2783-2796. doi: 10.1002/tox.23918. Epub 2023 Aug 1.
Nickel oxide nanoparticles (Nano NiO) have been shown to cause pulmonary fibrosis; But, the underlying epigenetic mechanisms remain poorly understood. In this study, we aimed to investigate the role of lncRNA AP000487.1 in regulating PRKCB DNA methylation and the Toll-like receptor 4 (TLR4)/ Myeloid differentiation primary response 88 (MyD88)/ Nuclear factor kappa-B (NF-κB) pathway in Nano NiO-induced collagen formation. We found that lncRNA AP000487.1 was able to bind to the promoter region of the PRKCB gene by Chromosomal RNA pull-down experiments (Ch-RNA pull-down). Moreover, Nano NiO exposure led to down-regulation of lncRNA AP000487.1 expression and PRKCB DNA methylation, resulting in up-regulation of PRKCB expression, activation of the TLR4/MyD88/NF-κB pathway, and increased collagen formation in BEAS-2B cells. Conversely, overexpression of lncRNA AP000487.1 restored PRKCB expression, reduced its hypomethylation and attenuated TLR4/MyD88/NF-κB pathway activation and collagen formation. Furthermore, treatment with the DNA methylation inhibitor, decitabine, alleviated Nano NiO-induced PRKCB2 expression, TLR4/MyD88/NF-κB pathway activation, and collagen formation. Additionally, using PRKCB2 overexpression plasmid, PRKCB2 siRNA, and PRKCB2 protein inhibitor LY317615 influenced NF-κB pathway activity and collagen formation. Finally, TLR4 inhibitor (TAK-242) restrained Nano NiO-induced MyD88/NF-κB pathway activation and excessive collagen formation. In summary, we demonstrated that the down-regulated lncRNA AP000487.1 could cause PRKCB hypomethylation and increased expression, resulting in NF-κB pathway activation and collagen formation in Nano NiO-induced BEAS-2B cells. This is the first study to reveal the role of lncRNA AP000487.1 in regulating collagen formation in Nano NiO-exposed BEAS-2B cells. Our study identified that lncRNA AP000487.1/PRKCB hypomethylation/NF-κB pathway was a regulatory axis of BEAS-2B cells collagen excessive formation. Our findings indicate that lncRNA AP000487.1 and PRKCB DNA methylation may function as biomarkers or potential targets in response to Nano NiO exposure.
氧化镍纳米颗粒（纳米NiO）已被证明可导致肺纤维化；但是，其潜在的表观遗传机制仍知之甚少。在本研究中，我们旨在探讨长链非编码RNA AP000487.1在调节PRKCB DNA甲基化以及Toll样受体4（TLR4）/髓样分化初级反应88（MyD88）/核因子κB（NF-κB）通路在纳米NiO诱导的胶原蛋白形成中的作用。我们通过染色体RNA下拉实验（Ch-RNA下拉）发现长链非编码RNA AP000487.1能够与PRKCB基因的启动子区域结合。此外，暴露于纳米NiO导致长链非编码RNA AP000487.1表达下调以及PRKCB DNA甲基化，从而导致PRKCB表达上调、TLR4/MyD88/NF-κB通路激活以及BEAS-2B细胞中胶原蛋白形成增加。相反，长链非编码RNA AP000487.1的过表达恢复了PRKCB表达，减少了其低甲基化，并减弱了TLR4/MyD88/NF-κB通路激活和胶原蛋白形成。此外，用DNA甲基化抑制剂地西他滨处理可减轻纳米NiO诱导的PRKCB2表达、TLR4/MyD88/NF-κB通路激活和胶原蛋白形成。此外，使用PRKCB2过表达质粒、PRKCB2 siRNA和PRKCB2蛋白抑制剂LY317615影响了NF-κB通路活性和胶原蛋白形成。最后，TLR4抑制剂（TAK-242）抑制了纳米NiO诱导的MyD88/NF-κB通路激活和过度的胶原蛋白形成。总之，我们证明了下调的长链非编码RNA AP000487.1可导致PRKCB低甲基化和表达增加，从而导致纳米NiO诱导的BEAS-2B细胞中NF-κB通路激活和胶原蛋白形成。这是第一项揭示长链非编码RNA AP000487.1在调节暴露于纳米NiO的BEAS-2B细胞中胶原蛋白形成作用的研究。我们的研究确定长链非编码RNA AP000487.1/PRKCB低甲基化/NF-κB通路是BEAS-2B细胞胶原蛋白过度形成的调节轴。我们的研究结果表明，长链非编码RNA AP000487.1和PRKCB DNA甲基化可能作为应对纳米NiO暴露的生物标志物或潜在靶点。
