LncRNA AP000487.1 regulates PRKCB DNA methylation‐mediated TLR4/MyD88/NF‐κB pathway in Nano NiO‐induced collagen formation in BEAS‐2B cells

Abstract

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.