title: RIP140 down-regulation alleviates acute lung injury via the inhibition of LPS-induced PPARγ promoter methylation.
abstract: Seriously inflammatory response of the lungs can induce acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) which are serious public health threats due to their high patient morbidity and mortality. While RIP140 is known to modulate proinflammatory cytokine production during an inflammatory response, its role in ALI/ARDS is unclear. In this study, we examined RIP140 and PPARγ protein expression in RAW 264.7 cells and lung tissue following LPS-induced ALI. RIP140 shRNA adenoviral knockdown significantly elevated PPARγ expression, inhibited TNF-α, IL-1β, and IL-6 production in vivo and in vitro. Conversely, treatment with a PPARγ antagonist (GW9662) reversed these outcomes. Furthermore, co-IP showed that endogenous and exogenous RIP140 interacted with DNMT3b in RAW 264.7 cells. Bisulfite conversion, pyrosequencing and activity assays demonstrated that PPARγ promoter methylation levels were increased and that PPARγ transcriptional activity was inhibited following LPS treatment in macrophages. Nevertheless, RIP140 knockdown reduced PPARγ promoter methylation levels and restored its transcriptional activity. These results indicate that RIP140 knockdown can inhibit the production of inflammation mediators and remit ALI via the repression of DNMT3b mediated PPARγ promoter methylation.
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China.
authors.forename: Chuanjiang
authors.initials: C
authors.lastname: Lei
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China.
authors.forename: Bingfeng
authors.initials: B
authors.lastname: He
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China.
authors.forename: Guansong
authors.initials: G
authors.lastname: Wang
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, 40037, China. Electronic address: wjc5577@126.com.
authors.forename: Jianchun
authors.initials: J
authors.lastname: Wang
mesh_terms: D055371:Acute Lung Injury / Q000235:genetics* / Q000503:physiopathology; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics*; D000813:Anilides / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D019175:DNA Methylation; D015536:Down-Regulation; D005786:Gene Expression Regulation / Q000235:genetics; D055785:Gene Knockdown Techniques; D018836:Inflammation Mediators / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity; D008264:Macrophages / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009687:Nuclear Proteins / Q000235:genetics*; D000078723:Nuclear Receptor Interacting Protein 1; D047495:PPAR gamma / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: C457499:2-chloro-5-nitrobenzanilide; D048868:Adaptor Proteins, Signal Transducing; D000813:Anilides; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D015850:Interleukin-6; D008070:Lipopolysaccharides; D009687:Nuclear Proteins; D000078723:Nuclear Receptor Interacting Protein 1; D047495:PPAR gamma; D014409:Tumor Necrosis Factor-alpha
keywords: Acute lung injury; Inflammation; Methylation; PPARγ; RIP140