1. Induction of circadian gene expression in human subcutaneous adipose-derived stem cells.
- Author
-
Wu X, Zvonic S, Floyd ZE, Kilroy G, Goh BC, Hernandez TL, Eckel RH, Mynatt RL, and Gimble JM
- Subjects
- ARNTL Transcription Factors, Adipocytes drug effects, Adipocytes pathology, Adipogenesis genetics, Adult, Basic Helix-Loop-Helix Transcription Factors genetics, Basic Helix-Loop-Helix Transcription Factors metabolism, Cell Cycle Proteins genetics, Cell Cycle Proteins metabolism, Cell Differentiation drug effects, Cells, Cultured, Cryptochromes, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Dexamethasone pharmacology, Female, Flavoproteins genetics, Flavoproteins metabolism, Gene Expression Regulation drug effects, Glycogen Synthase Kinase 3 antagonists & inhibitors, Humans, Lithium Chloride pharmacology, Middle Aged, Nuclear Proteins metabolism, Nuclear Receptor Subfamily 1, Group D, Member 1, Period Circadian Proteins, Receptors, Cytoplasmic and Nuclear genetics, Receptors, Cytoplasmic and Nuclear metabolism, Repressor Proteins genetics, Repressor Proteins metabolism, Rosiglitazone, Stem Cells drug effects, Stem Cells pathology, Thiazolidinediones pharmacology, Transcription Factors metabolism, Adipocytes metabolism, Circadian Rhythm genetics, Gene Expression Regulation physiology, Nuclear Proteins genetics, Stem Cells metabolism, Transcription Factors genetics
- Abstract
Objective: Genes encoding the circadian transcriptional apparatus exhibit robust oscillatory expression in murine adipose tissues. This study tests the hypothesis that human subcutaneous adipose-derived stem cells (ASCs) provide an in vitro model in which to monitor the activity of the core circadian transcriptional apparatus., Research Methods and Procedures: Primary cultures of undifferentiated or adipocyte-differentiated ASCs were treated with dexamethasone, rosiglitazone, or 30% fetal bovine serum. The response of undifferentiated ASCs to dexamethasone was further evaluated in the presence of lithium chloride. Lithium inhibits glycogen synthase kinase 3, a key component of the circadian apparatus. Total RNA was harvested at 4-hour intervals over 48 hours and examined by real-time reverse transcription polymerase chain reaction (RT-PCR)., Results: Adipocyte-differentiated cells responded more rapidly to treatments than their donor-matched undifferentiated controls; however, the period of the circadian gene oscillation was longer in the adipocyte-differentiated cells. Dexamethasone generated circadian gene expression patterns with mean periods of 25.4 and 26.7 hours in undifferentiated and adipocyte-differentiated ASCs, respectively. Both rosiglitazone and serum shock generated a significantly longer period in adipocyte-differentiated ASCs relative to undifferentiated ASCs. The Bmal1 profile was phase-shifted by approximately 8 to 12 hours relative to Per1, Per3, and Cry2, consistent with their expression in vivo. Lithium chloride inhibited adipogenesis and significantly lengthened the period of Per3 and Rev-erbalpha gene expression profiles by >5 hours in dexamethasone-activated undifferentiated ASCs., Discussion: These results support the initial hypothesis and validate ASCs as an in vitro model for the analysis of circadian biology in human adipose tissue.
- Published
- 2007
- Full Text
- View/download PDF