title: Histone demethylase UTX counteracts glucocorticoid deregulation of osteogenesis by modulating histone-dependent and -independent pathways.
abstract: Excess glucocorticoid administration impairs osteogenic activities, which raises the risk of osteoporotic disorders. Epigenetic methylation of DNA and histone regulates the lineage commitment of progenitor cells. This study was undertaken to delineate the actions of histone lysine demethylase 6a (UTX) with regard to the glucocorticoid impediment of osteogenic differentiation. Osteogenic progenitor cells responded to supraphysiological glucocorticoid by elevating CpG dinucleotide methylation proximal to transcription start sites within Runx2 and osterix promoters and Wnt inhibitor Dickkopf-1 (Dkk1) expression concomitant with low UTX expression. 5'-Aza-deoxycystidine demethylation of Runx2 and osterix promoters abolished the glucocorticoid inhibition of mineralized matrix accumulation. Gain of UTX function attenuated the glucocorticoid-induced loss of osteogenic differentiation, whereas UTX silencing escalated adipogenic gene expression and adipocyte formation. UTX sustained osteogenic gene transcription through maintaining its occupancy to Runx2 and osterix promoters. It also mitigated the trimethylation of histone 3 at lysine 27 (H3K27me3), which reduced H3K27me3 enrichment to Dkk1 promoter and thereby lowered Dkk1 transcription. Modulation of β-catenin and Dkk1 actions restored UTX signaling in glucocorticoid-stressed cells. In vivo, UTX inhibition by exogenous methylprednisolone and GSK-J4 administration, an effect that disturbed H3K27me3, β-catenin, Dkk1, Runx2, and osterix levels, exacerbated trabecular microarchitecture loss and marrow adiposity. Taken together, glucocorticoid reduction of UTX function hindered osteogenic differentiation. Epigenetic hypomethylation of osteogenic transcription factor promoters and H3K27 contributed to the UXT alleviation of Dkk1 transcription and osteogenesis in glucocorticoid-stressed osteogenic progenitor cells. Control of UTX action has an epigenetic perspective of curtailing glucocorticoid impairment of osteogenic differentiation and bone mass.
  
  
  
  UTX attenuates glucocorticoid deregulation of osteogenesis and adipogenesis. UTX reduces Runx2 promoter methylation and H3K27me3 enrichment in the Dkk1 promoter. β-catenin and Dkk1 modulate the glucocorticoid inhibition of UTX signaling. UTX inhibition exacerbates bone mass, trabecular microstructure and fatty marrow. UTX signaling is indispensable in fending off glucocorticoid-impaired osteogenesis.
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Graduate Institute of Clinical Medical Sciences, Chang Gung University College of Medicine, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Feng-Sheng
authors.initials: FS
authors.lastname: Wang
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Wei-Shiung
authors.initials: WS
authors.lastname: Lian
authors.affiliation: Department of Orthopedic Surgery, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Mel S
authors.initials: MS
authors.lastname: Lee
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Wen-Tsan
authors.initials: WT
authors.lastname: Weng
authors.affiliation: Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Ying-Hsien
authors.initials: YH
authors.lastname: Huang
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Yu-Shan
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Yi-Chih
authors.initials: YC
authors.lastname: Sun
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.|Core Laboratory for Phenomics and Diagonistics, Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan.
authors.forename: Shing-Long
authors.initials: SL
authors.lastname: Wu
authors.affiliation: Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan. stemcorelab@cgmh.org.tw.
authors.forename: Pei-Chin
authors.initials: PC
authors.lastname: Chuang
authors.affiliation: Graduate Institute of Clinical Medical Sciences, Chang Gung University College of Medicine, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan. kojy@cgmh.org.tw.|Department of Orthopedic Surgery, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niao-Sung District, Kaohsiung, 83303, Taiwan. kojy@cgmh.org.tw.
authors.forename: Jih-Yang
authors.initials: JY
authors.lastname: Ko
mesh_terms: D000818:Animals; D001374:Azacitidine / Q000031:analogs & derivatives / Q000378:metabolism; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics; D019175:DNA Methylation / Q000187:drug effects / Q000235:genetics; D000077209:Decitabine; D005938:Glucocorticoids / Q000494:pharmacology*; D056466:Histone Demethylases / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000187:drug effects / Q000378:metabolism*; D015151:Immunoblotting; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D008745:Methylation / Q000187:drug effects; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D000076182:Sp7 Transcription Factor / Q000235:genetics; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; C501127:Dkk1 protein, mouse; D005938:Glucocorticoids; D006657:Histones; D036341:Intercellular Signaling Peptides and Proteins; D000076182:Sp7 Transcription Factor; D051176:beta Catenin; D000077209:Decitabine; D056466:Histone Demethylases; C111778:Utx protein, mouse; D001374:Azacitidine
keywords: Dkk1; Glucocorticoid; Methylation; Osteogenesis; UTX