title: Suppression of discoidin domain receptor 1 expression enhances the chondrogenesis of adipose-derived stem cells.
abstract: Effectively directing the chondrogenesis of adipose-derived stem cells (ADSCs) to engineer articular cartilage represents an important challenge in ADSC-based articular cartilage tissue engineering. The discoidin domain receptor 1 (DDR1) has been shown to affect cartilage homeostasis; however, little is known about the roles of DDR1 in ADSC chondrogenesis. In this study, we used the three-dimensional culture pellet culture model system with chondrogenic induction to investigate the roles of DDR1 in the chondrogenic differentiation of human ADSCs (hADSCs). Real-time polymerase chain reaction and Western blot were used to detect the expression of DDRs and chondrogenic genes. Sulfated glycosaminoglycan (sGAG) was detected by Alcian blue and dimethylmethylene blue (DMMB) assays. Terminal deoxy-nucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining was used to assess cell death. During the chondrogenesis of hADSCs, the expression of DDR1 but not DDR2 was significantly elevated. The depletion of DDR1 expression in hADSCs using short hairpin RNA increased the expression of chondrogenic genes (SOX-9, collagen type II, and aggrecan) and cartilaginous matrix deposition (collagen type II and sGAG) and only slightly increased cell death (2-8%). DDR1 overexpression in hADSCs decreased the expression of chondrogenic genes (SOX-9, collagen type II, and aggrecan) and sGAG and enhanced hADSC survival. Moreover, DDR1-depleted hADSCs showed decreased expression of the terminal differentiation genes runt-related transcription factor 2 (Runx2) and matrix metalloproteinase 13 (MMP-13). These results suggest that DDR1 suppression may enhance ADSC chondrogenesis by enhancing the expression of chondrogenic genes and cartilaginous matrix deposition. We proposed that the suppression of DDR1 in ADSCs may be a candidate strategy of genetic modification to optimize ADSC-based articular cartilage tissue engineering.
authors: Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Orthopaedic Research Center, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors: Shun-Cheng
authors: SC
authors: Wu
authors: Department of Family Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan;
authors: Hsu-Feng
authors: HF
authors: Hsiao
authors: Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Orthopaedic Research Center, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors: Mei-Ling
authors: ML
authors: Ho
authors: Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors: Yung-Li
authors: YL
authors: Hung
authors: Orthopaedic Research Center, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthopedics, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthopedics, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors: Je-Ken
authors: JK
authors: Chang
authors: Orthopaedic Research Center, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthopedic Surgery, University of Virginia, Charlottesville, Virginia; Medical Device Innovation Center, National Cheng-Kung University, Tainan, Taiwan; and Skeleton-Joint Research Center, National Cheng-Kung University, Tainan, Taiwan.
authors: Gwo-Jaw
authors: GJ
authors: Wang
authors: Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Physiology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Orthopaedic Research Center, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; czwang@kmu.edu.tw.
authors: Chau-Zen
authors: CZ
authors: Wang
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D002470:Cell Survival; D002478:Cells, Cultured; D019902:Chondrocytes / Q000378:metabolism*; D020219:Chondrogenesis; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D000070819:Discoidin Domain Receptor 1; D005786:Gene Expression Regulation; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D053509:Matrix Metalloproteinase 13 / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D055758:SOX9 Transcription Factor / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013234:Stem Cells / Q000378:metabolism*; D050151:Subcutaneous Fat / Q000166:cytology / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection
chemical_list: C508319:ACAN protein, human; D053674:Aggrecans; D024043:Collagen Type II; D050659:Core Binding Factor Alpha 1 Subunit; D006025:Glycosaminoglycans; D012333:RNA, Messenger; C493709:RUNX2 protein, human; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; C092030:DDR1 protein, human; D000070819:Discoidin Domain Receptor 1; D020794:Receptor Protein-Tyrosine Kinases; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13
keywords: ADSCs; DDR1; adipose-derived stem cells; articular cartilage tissue engineering; chondrogenesis; discoidin domain receptor 1