title: Declined Expression of Histone Deacetylase 6 Contributes to Periodontal Ligament Stem Cell Aging.
abstract: Identification of regulators for aging-associated stem cell (SC) dysfunctions is a critical topic in SC biology and SC-based therapies. Periodontal ligament stem cell (PDLSC), a kind of dental mesenchymal SC with dental regeneration potential, ages with functional deterioration in both in vivo and ex vivo expansion. However, little is known about regulators for PDLSC aging.
  
  
  
  Expression changes of a potential regulator for PDLSC aging, histone deacetylase 6 (HDAC6), were evaluated within various models. Senescence-associated phenotypic and functional alternations of PDLSC in loss-of-function models for HDAC6 were examined using HDAC6-specific pharmacologic inhibitors or RNA interference-based knockdown. Involvement of p27Kip1in HDAC6-associated aging was demonstrated by its acetylation and stability changes along with overexpression or functional inhibition of HDAC6.
  
  
  
  Expression of HDAC6 decreased significantly in replicative senescence and induced SC aging models. Loss-of-function experiments suggested that pharmacologic inhibition of deacetylase activity of HDAC6 accelerated PDLSC senescence and impaired its SC activities, which showed reduced osteogenic differentiation and diminished migration capacities. Examination of markers for proliferative exhaustion of SCs revealed that protein level of p27Kip1was specifically elevated after HDAC6 inhibition. HDAC6 physically interacted with p27Kip1and could deacetylate p27Kip1. Importantly, acetylation of p27Kip1was negatively regulated by HDAC6, which correlated with alteration of p27Kip1protein levels.
  
  
  
  Data suggest that HDAC6 plays an important role in PDLSC aging, which is dependent, at least partially, on regulation of p27Kip1acetylation.
authors: Department of Orthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors: Qian
authors: Q
authors: Li
authors: Department of Orthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors: Yushi
authors: Y
authors: Ma
authors: Department of Orthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors: Yunyan
authors: Y
authors: Zhu
authors: Department of Orthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors: Ting
authors: T
authors: Zhang
authors: Department of Orthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
authors: Yanheng
authors: Y
authors: Zhou
mesh_terms: D000293:Adolescent; D000328:Adult; D016922:Cellular Senescence; D005260:Female; D000073864:Histone Deacetylase 6 / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010513:Periodontal Ligament / Q000166:cytology*; D010641:Phenotype; D013234:Stem Cells / Q000201:enzymology*
chemical_list: D000073864:Histone Deacetylase 6
keywords: Acetylation; aging; cyclin-dependent kinase inhibitor p27; histone deacetylases; periodontal ligament; proteins; stem cells