title: A new preadipocyte cell line, AP-18, established from adult mouse adipose tissue.
abstract: Establishing preadipocyte cell lines from mature adipose tissues could help lead to a better understanding of adipogenesis. We have established a unique preadipocyte cell line, AP-18, derived from the subepidermal layer of ear skin from an adult C3H/HeM mouse. AP-18 cells exhibit fibroblast-like morphology, slow growth, and contact inhibition. The doubling time of AP-18 cells is 50-60 h, which is about 2-fold longer than that of well-known 3T3-L1 cells derived from mouse embryos. A small population of AP-18 cells spontaneously differentiates into adipocytes by 8 days after confluence, as judged by the accumulation of triglyceride droplets. Treatment of confluent AP-18 preadipocytes with adipogenic agents, containing dexamethasone, 3-methyl-1-isobutylxanthine, and insulin, increased triglyceride contents about 5-fold compared to the contents in untreated cells. We also analyzed mRNA expression profiles for key transcription factors involved in adipocyte differentiation, peroxisome proliferator-activated receptor (PPAR)gamma and the CCAAT/enhancer binding protein (C/EBP) family, and for differentiation markers, aP2, adipocyte-specific fatty acid-binding protein and adipsin, adipocyte-specific serine protease. AP-18 preadipocytes express mRNAs for C/EBPbeta, C/EBPalpha, PPARgamma, and aP2 before differentiation, but not adipsin mRNA. Expression of aP2 mRNA was increased in fully differentiated AP-18 cells. Likewise, expression of adipsin mRNA was increased after induced differentiation of AP-18 cells and reached the highest level in fully differentiated adipocytes. Thus, differentiation of AP-18 cells is associated with the increased expression of aP2 and adipsin mRNAs. The newly established AP-18 cell line provides a useful model for investigating adipocyte differentiation and adipogenesis.
authors.affiliation: Division of Advanced Surgical Science and Technology, Graduate School of Medicine Tohoku University, Sendai. dovaline@mail.tains.tohoku.ac.jp
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Doi
authors.forename: Nakui
authors.initials: N
authors.lastname: Masaki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Komatsu
authors.forename: Keisei
authors.initials: K
authors.lastname: Fujimori
authors.forename: Susumu
authors.initials: S
authors.lastname: Satomi
mesh_terms: D016475:3T3 Cells; D017667:Adipocytes / Q000166:cytology* / Q000187:drug effects; D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D015415:Biomarkers; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D051379:Mice; D008858:Microscopy, Phase-Contrast; D047495:PPAR gamma / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D040521:Subcutaneous Tissue
chemical_list: D015415:Biomarkers; D007328:Insulin; D047495:PPAR gamma; D012333:RNA, Messenger; D003907:Dexamethasone