Overexpression of interleukin 6 () has been proposed to contribute to pulmonary fibrosis and other fibrotic diseases. However， the regulatory mechanisms and the role of in fibrosis remain poorly understood. Epigenetics refers to alterations of gene expression without changes in the DNA sequence. Alternation of chromatin accessibility by histone acetylation acts as a critical epigenetic mechanism to regulate various gene transcriptions. The goal of this study was to determine the impact of in paraquat (PQ)-induced pulmonary fibrosis and to explore whether the epigenetic regulations may play a role in transcriptional regulation of . In PQ-treated lungs and macrophages， we found that the mRNA and protein exp... More
Overexpression of interleukin 6 () has been proposed to contribute to pulmonary fibrosis and other fibrotic diseases. However， the regulatory mechanisms and the role of in fibrosis remain poorly understood. Epigenetics refers to alterations of gene expression without changes in the DNA sequence. Alternation of chromatin accessibility by histone acetylation acts as a critical epigenetic mechanism to regulate various gene transcriptions. The goal of this study was to determine the impact of in paraquat (PQ)-induced pulmonary fibrosis and to explore whether the epigenetic regulations may play a role in transcriptional regulation of . In PQ-treated lungs and macrophages， we found that the mRNA and protein expression of was robustly increased in a time-dependent and a dose-dependent manner. Our data demonstrated that PQ-induced expression in macrophages plays a central role in pulmonary fibrosis through enhanced epithelial-to-mesenchymal transition (EMT). expression and its role to enhance PQ-induced pulmonary fibrosis were increased by histone deacetylase (HDAC) inhibition and prevented by histone acetyltransferase (HAT) inhibition. In addition， the ability of CRISPR-ON transcription activation system (CRISPR-ON) to promote transcription of was enhanced by HDAC inhibitor and blocked by HAT inhibitor. Chromatin immunoprecipitation experiments revealed that HDAC inhibitor increased histones activation marks H3K4me3 and H3K9ac at promoter regions. In conclusion， functioning through EMT in PQ-induced pulmonary fibrosis was regulated dynamically by HDAC and HAT both and epigenetically regulating chromatin accessibility.
