{"title":"Sustained activation of NF-κB through constitutively active IKKβ leads to senescence bypass in murine dermal fibroblasts.","authors":"Masayuki Harada, Kanae Su-Harada, Takeshi Kimura, Koh Ono, Noboru Ashida","doi":"10.1080/15384101.2024.2325802","DOIUrl":null,"url":null,"abstract":"<p><p>Although the transcription factor nuclear factor κB (NF-κB) plays a central role in the regulation of senescence-associated secretory phenotype (SASP) acquisition, our understanding of the involvement of NF-κB in the induction of cellular senescence is limited. Here, we show that activation of the canonical NF-κB pathway suppresses senescence in murine dermal fibroblasts. IκB kinase β (IKKβ)-depleted dermal fibroblasts showed ineffective NF-κB activation and underwent senescence more rapidly than control cells when cultured under 20% oxygen conditions, as indicated by senescence-associated β-galactosidase (SA-β-gal) staining and <i>p16<sup>INK4a</sup></i> mRNA levels. Conversely, the expression of <u>c</u>onstitutively <u>a</u>ctive IKKβ (IKKβ-CA) was sufficient to drive senescence bypass. Notably, the expression of a degradation-resistant form of inhibitor of κB (IκB), which inhibits NF-κB nuclear translocation, abolished senescence bypass, suggesting that the inhibitory effect of IKKβ-CA on senescence is largely mediated by NF-κB. We also found that IKKβ-CA expression suppressed the derepression of <i>INK4/Arf</i> genes and counteracted the senescence-associated loss of <i>Ezh2</i>, a catalytic subunit of the Polycomb repressive complex 2 (PRC2). Moreover, pharmacological inhibition of Ezh2 abolished IKKβ-CA-induced senescence bypass. We propose that NF-κB plays a suppressive role in the induction of stress-induced senescence through sustaining <i>Ezh2</i> expression.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3000,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11057680/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Electronic Materials","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1080/15384101.2024.2325802","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/3/10 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
Although the transcription factor nuclear factor κB (NF-κB) plays a central role in the regulation of senescence-associated secretory phenotype (SASP) acquisition, our understanding of the involvement of NF-κB in the induction of cellular senescence is limited. Here, we show that activation of the canonical NF-κB pathway suppresses senescence in murine dermal fibroblasts. IκB kinase β (IKKβ)-depleted dermal fibroblasts showed ineffective NF-κB activation and underwent senescence more rapidly than control cells when cultured under 20% oxygen conditions, as indicated by senescence-associated β-galactosidase (SA-β-gal) staining and p16INK4a mRNA levels. Conversely, the expression of constitutively active IKKβ (IKKβ-CA) was sufficient to drive senescence bypass. Notably, the expression of a degradation-resistant form of inhibitor of κB (IκB), which inhibits NF-κB nuclear translocation, abolished senescence bypass, suggesting that the inhibitory effect of IKKβ-CA on senescence is largely mediated by NF-κB. We also found that IKKβ-CA expression suppressed the derepression of INK4/Arf genes and counteracted the senescence-associated loss of Ezh2, a catalytic subunit of the Polycomb repressive complex 2 (PRC2). Moreover, pharmacological inhibition of Ezh2 abolished IKKβ-CA-induced senescence bypass. We propose that NF-κB plays a suppressive role in the induction of stress-induced senescence through sustaining Ezh2 expression.