title: Quantitative determination of high-temperature requirement protein A1 and its possible associated molecules during induced reparative dentin formation.
abstract: BACKGROUND
  The equilibrium of inhibitors and inducers plays an important role in the mineralization of dentin during dentinogenesis. High-temperature requirement protein A1 (HtrA1) is a novel bone mineralization inhibitor involved in physiological and pathological bone formation. However, the expression of HtrA1 in tooth mineralization is unknown. The purpose of the present study was to investigate the localization and quantity of HtrA1 and its possible related molecules during induced reparative dentin formation.
  
  
  METHODS
  Rats were randomly sacrificed after direct pulp capping on days 0, 7, 14, and 21. Maxillary segments were obtained and routinely prepared for histological analysis, immunohistochemistry, quantum dots-based double immunofluorescence, and CRi's Nuance imaging system (CRI, Woburn, MA)-based quantitative determination.
  
  
  RESULTS
  The square measure values of reparative dentin significantly increased on day 7 and continued to increase until day 21. HtrA1, matrix Gla protein (MGP), nestin, and bone sialoprotein were positively stained and colocalized in the odontoblasts and/or odontoblast-like cells zone and reparative dentin during induced reparative dentin formation. The expressions of HtrA1 and MGP were significantly enhanced after direct pulp capping on day 7 and did not significantly change between days 7, 14, and day 21. Both expressions of HtrA1 and MGP were positively correlated with the square measure values of reparative dentin; however, no correlation was found between the expressions of HtrA1 and MGP.
  
  
  CONCLUSIONS
  HtrA1 could be observed and might possibly be involved in the process of reparative dentin formation associated with MGP.
authors.affiliation: Department of State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, PR China.
authors.forename: Xianyu
authors.initials: X
authors.lastname: Li
authors.forename: Mi
authors.initials: M
authors.lastname: Zhou
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.forename: Ran
authors.initials: R
authors.lastname: Li
authors.forename: Nana
authors.initials: N
authors.lastname: Han
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D017607:Aluminum Compounds; D000818:Animals; D017610:Calcium Compounds; D002135:Calcium-Binding Proteins / Q000032:analysis / Q000378:metabolism; D003782:Dental Pulp / Q000166:cytology / Q000378:metabolism; D003785:Dental Pulp Capping; D003809:Dentin, Secondary / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism*; D004338:Drug Combinations; D016326:Extracellular Matrix Proteins / Q000032:analysis / Q000378:metabolism*; D000074289:High-Temperature Requirement A Serine Peptidase 1; D058574:Integrin-Binding Sialoprotein / Q000032:analysis / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000032:analysis / Q000378:metabolism; D008297:Male; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000378:metabolism; D064231:Nestin; D009804:Odontoblasts / Q000737:chemistry / Q000201:enzymology*; D010087:Oxides; D057872:Pulp Capping and Pulpectomy Agents; D045663:Quantum Dots; D051381:Rats; D017208:Rats, Wistar; D012697:Serine Endopeptidases / Q000032:analysis / Q000378:metabolism*; D012815:Signal Processing, Computer-Assisted; D017640:Silicates; D014074:Tooth Calcification / Q000502:physiology; D000097568:Matrix Gla Protein
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D002135:Calcium-Binding Proteins; D004338:Drug Combinations; D016326:Extracellular Matrix Proteins; D000074289:High-Temperature Requirement A Serine Peptidase 1; D058574:Integrin-Binding Sialoprotein; D007381:Intermediate Filament Proteins; D009419:Nerve Tissue Proteins; D064231:Nestin; D010087:Oxides; D057872:Pulp Capping and Pulpectomy Agents; D012697:Serine Endopeptidases; D017640:Silicates; D000097568:Matrix Gla Protein; C577486:Nes protein, rat; C086631:mineral trioxide aggregate; C575914:HtrA1 protein, rat