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Song Q, Yong HM, Yang LL, Liang YQ, Liu ZX, Niu DS, Bai ZG. Lycium barbarum polysaccharide protects against osteonecrosis of femoral head via regulating Runx2 expression. Injury 2022; 53:1361-1367. [PMID: 35082056 DOI: 10.1016/j.injury.2021.12.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/23/2021] [Accepted: 12/30/2021] [Indexed: 02/02/2023]
Abstract
BACKGROUND Osteonecrosis of femoral head (ONFH) is a pathological state caused by lack of blood supply in femoral head. This study aimed to explore the function of Lycium barbarum polysaccharide (LBP), an antioxidant agent extracted from L. barbarum, on ONFH. METHODS Osteonecrosis rat model was generated using lipopolysaccharide (LPS) and methylprednisolone followed by examination of body weight, blood glucose, morphology, and BMSC osteoblast differentiation. The effect and underlying mechanism of LBP on the proliferation, apoptosis, and osteoblast differentiation of BMSC were determined with or without LPS or hypoxia treatment using CCK-8. Alizarin Red S staining, flow cytometry, and western blot, respectively. RESULT LBP could protect against glucocorticoid-induced ONFH in rats, resulting in improved sparse trabecular bone, empty lacunae and bone cell coagulation. Moreover, LBP promoted the proliferation and osteoblast differentiation of bone mesenchymal-derived stem cells (BMSCs) in a dose-dependent manner. Furthermore, LBP enhanced osteoblast differentiation of BMSCs under hypoxia condition. Mechanistically, we found that LBP treatment enhanced Runx2 and ALP expression in BMSCs. LBP restored the expression of Runx2 and ALP under hypoxia, suggesting that LBP might be involved in regulating Runx2/ALP expression and contributed to osteoblast differentiation. Knockdown of Runx2 significantly inhibited BMSCs proliferation, while LBP treatment did not rescue the osteoblast differentiation ability of BMSCs with Runx2 knockdown. CONCLUSION Our findings suggested that LBP protects against ONFH via regulating Runx2 expression, which could be utilized to treat patients suffering ONFH.
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Affiliation(s)
- Qiang Song
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Hai-Ming Yong
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Lv-Lin Yang
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Yu-Qi Liang
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Ze-Xin Liu
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Dong-Sheng Niu
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China
| | - Zhi-Gang Bai
- People's Hospital of Ningxia Hui Autonomous Region, No.301 Zhengyuan North Street, Yinchuan, Ningxia 750021, China.
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Kim WJ, Shin HL, Kim BS, Kim HJ, Ryoo HM. RUNX2-modifying enzymes: therapeutic targets for bone diseases. Exp Mol Med 2020; 52:1178-1184. [PMID: 32788656 PMCID: PMC8080656 DOI: 10.1038/s12276-020-0471-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 01/01/2023] Open
Abstract
RUNX2 is a master transcription factor of osteoblast differentiation. RUNX2 expression in the bone and osteogenic front of a suture is crucial for cranial suture closure and membranous bone morphogenesis. In this manner, the regulation of RUNX2 is precisely controlled by multiple posttranslational modifications (PTMs) mediated by the stepwise recruitment of multiple enzymes. Genetic defects in RUNX2 itself or in its PTM regulatory pathways result in craniofacial malformations. Haploinsufficiency in RUNX2 causes cleidocranial dysplasia (CCD), which is characterized by open fontanelle and hypoplastic clavicles. In contrast, gain-of-function mutations in FGFRs, which are known upstream stimulating signals of RUNX2 activity, cause craniosynostosis (CS) characterized by premature suture obliteration. The identification of these PTM cascades could suggest suitable drug targets for RUNX2 regulation. In this review, we will focus on the mechanism of RUNX2 regulation mediated by PTMs, such as phosphorylation, prolyl isomerization, acetylation, and ubiquitination, and we will summarize the therapeutics associated with each PTM enzyme for the treatment of congenital cranial suture anomalies.
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Affiliation(s)
- Woo-Jin Kim
- Basic Research Lab for "Epigenetic Regeneration of Aged Skeleto-Muscular System (ERASMUS)", Department of Molecular Genetics and Dental Pharmacology, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Hye-Lim Shin
- Basic Research Lab for "Epigenetic Regeneration of Aged Skeleto-Muscular System (ERASMUS)", Department of Molecular Genetics and Dental Pharmacology, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Bong-Soo Kim
- Basic Research Lab for "Epigenetic Regeneration of Aged Skeleto-Muscular System (ERASMUS)", Department of Molecular Genetics and Dental Pharmacology, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Hyun-Jung Kim
- Basic Research Lab for "Epigenetic Regeneration of Aged Skeleto-Muscular System (ERASMUS)", Department of Molecular Genetics and Dental Pharmacology, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Hyun-Mo Ryoo
- Basic Research Lab for "Epigenetic Regeneration of Aged Skeleto-Muscular System (ERASMUS)", Department of Molecular Genetics and Dental Pharmacology, School of Dentistry, Dental Research Institute, Seoul National University, Seoul, South Korea.
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Hurley MM, Adams DJ, Wang L, Jiang X, Burt PM, Du E, Xiao L. Accelerated fracture healing in transgenic mice overexpressing an anabolic isoform of fibroblast growth factor 2. J Cell Biochem 2016; 117:599-611. [DOI: 10.1002/jcb.25308] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 08/04/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Marja M. Hurley
- Department of Medicine; University of Connecticut School of Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Douglas J. Adams
- Department of Orthopaedic Surgery; University of Connecticut School of Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Liping Wang
- Department of Craniofacial Sciences; University of Connecticut School of Dental Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Xi Jiang
- Department of Craniofacial Sciences; University of Connecticut School of Dental Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Patience Meo Burt
- Department of Medicine; University of Connecticut School of Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Erxia Du
- Department of Medicine; University of Connecticut School of Medicine, UCONN Health; Farmington Connecticut 06030-052
| | - Liping Xiao
- Department of Medicine; University of Connecticut School of Medicine, UCONN Health; Farmington Connecticut 06030-052
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Continuous infusion of angiotensin II modulates hypertrophic differentiation and apoptosis of chondrocytes in cartilage formation in a fracture model mouse. Hypertens Res 2015; 38:382-93. [PMID: 25693858 DOI: 10.1038/hr.2015.18] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 12/08/2014] [Accepted: 12/15/2014] [Indexed: 12/16/2022]
Abstract
Although components of the renin-angiotensin system (RAS) are reported to be expressed in cultured chondrocytes and cartilage, little is known about the precise function of Angiotensin II (Ang II) in chondrocytes. In this study, we employed a rib fracture model mouse to investigate the effect of Ang II on chondrocytes. Ang II type 1 receptor (AT1R) was expressed in chondrocytes in the growth plate of mouse tibia. Continuous infusion of Ang II to rib-fractured mice resulted in a significant increase in the volume of cartilage, suggesting Ang II-induced hypertrophic differentiation of chondrocytes. It was also confirmed by a significant increase in the mRNA expression of Sox9 and runt-related transcription factor 2 (Runx2), which are genes related to chondrocyte differentiation, and type X collagen, matrix metalloproteinase (MMP)-13 and Indian hedgehog (Ihh), which are hypertrophic chondrocyte-specific molecular markers. Chondrocyte hypertrophy with upregulation of these genes was attenuated by administration of olmesartan, an AT1R blocker, but not by hydralazine. Moreover, Ang II infusion significantly suppressed apoptosis of chondrocytes, accompanied by significant induction of mRNA expression of bcl-2 and bcl-xL. Olmesartan, but not hydralazine, significantly attenuated the reduction of apoptotic cells and the increase in anti-apoptotic genes induced by Ang II infusion. Overall, the present study demonstrated that Ang II promoted hypertrophic differentiation of chondrocytes and reduced apoptosis of hypertrophic chondrocytes independently of high blood pressure. The present data indicate the role of Ang II in cartilage, and might provide a new concept for treatment of cartilage diseases.
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Matziolis D, Tuischer J, Matziolis G, Kasper G, Duda G, Perka C. Osteogenic predifferentiation of human bone marrow-derived stem cells by short-term mechanical stimulation. Open Orthop J 2011; 5:1-6. [PMID: 21270950 PMCID: PMC3027083 DOI: 10.2174/1874325001105010001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 07/08/2010] [Accepted: 07/19/2010] [Indexed: 11/22/2022] Open
Abstract
It is commonly accepted that bone marrow-derived stem cells (BMSCs) have to be expanded in vitro, but a prolonged time in culture decreases their multilineage potential. Mechanical and biological stimuli have been used to improve their osteogenic potential. While long-term stimulation has been shown to improve osteogenic differentiation, it remains to be seen whether short-term stimulation is also sufficient. We investigated the influence of 24 hours' cyclic loading (0.05Hz, 4kPa) on gene expression of human BMSCs in three-dimensional fibrin-DMEM constructs (n=7) in a compression bioreactor using DNA-array technology. Expression of the following genes showed a significant increase after mechanical stimulation: 2.6-fold osteopontin (OPN) and integrin-β1 (ITGB1), 2.2-fold transforming growth factor-β-receptor 1 (TGF-β-R1) and 2.4-fold SMAD5 expression, compared to controls without mechanical stimulation (p<0.05 each). Platelet-derived growth factor-α (PDGF-α ) and annexin-V were also significantly overexpressed, the mechanical stimulation resulting in a 1.8-fold and 1.6-fold expression (p<0.05). Cells were identified as osteoblast precursors with a high proliferative capacity. Given the identical in-vitro environment for both groups, the increase in gene expression has been interpreted as a direct influence of cyclic mechanical stimulation on osteogenic differentiation. It may be postulated that short-term mechanical stimulation results in an improved osseous integration of tissue engineered grafts in bone defect healing.
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Kita K, Kimura T, Nakamura N, Yoshikawa H, Nakano T. PI3K/Akt signaling as a key regulatory pathway for chondrocyte terminal differentiation. Genes Cells 2008; 13:839-50. [DOI: 10.1111/j.1365-2443.2008.01209.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gordeladze JO, Noël D, Bony C, Apparailly F, Louis-Plence P, Jorgensen C. Transient down-regulation of cbfa1/Runx2 by RNA interference in murine C3H10T1/2 mesenchymal stromal cells delays in vitro and in vivo osteogenesis, but does not overtly affect chondrogenesis. Exp Cell Res 2008; 314:1495-506. [PMID: 18313048 DOI: 10.1016/j.yexcr.2007.12.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 12/06/2007] [Accepted: 12/15/2007] [Indexed: 11/16/2022]
Abstract
In order to ensure that MSCs designed for in vivo cartilage repair do not untowardly differentiate into osteoblasts and mineralize in situ, we tested whether siRNA-induced suppression of cbfa1/Runx2 affected the osteogenic and chondrogenic differentiation potential of the murine cell line C3H10T1/2. Anti-cbfa1/Runx2 siRNA decreased the levels of cbfa1/Runx2 mRNA and protein by 65-80%, and also markedly reduced the expression of osteoblast-related genes such as Dlx5, osterix, collagen type I, alkaline phosphatase (AP), osteocalcin, SPARC/osteonectin and osteopontin, leading to a temporal expression of AP enzyme activity and mineralization potential delayed by at least some 7-9 days. Furthermore, siRNA-transfected cells, grown under chondrogenic conditions did not display biologically significant changes in the expression of aggrecan, collagen type II or type X, or histology when grown in micropellets or monolayer cultures. Finally, when cells were propagated in osteogenic medium and injected into the tibial muscles of SCID mice, no overtly mineralized bone tissue emerged. These experiments indicate that a major transient reduction of cbfa1/Runx2 expression in MSCs is sufficient to delay osteoblastic differentiation, both in vitro and in vivo, while chondrogenesis seemed to be sustained.
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Affiliation(s)
- Jan O Gordeladze
- Institute of Basal Medical Sciences, Department of Biochemistry, University of Oslo, Norway.
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Bustamante M, Nogués X, Agueda L, Jurado S, Wesselius A, Cáceres E, Carreras R, Ciria M, Mellibovsky L, Balcells S, Díez-Pérez A, Grinberg D. Promoter 2 -1025 T/C polymorphism in the RUNX2 gene is associated with femoral neck bmd in Spanish postmenopausal women. Calcif Tissue Int 2007; 81:327-32. [PMID: 17878995 DOI: 10.1007/s00223-007-9069-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2007] [Accepted: 07/27/2007] [Indexed: 11/25/2022]
Abstract
Stimulation of bone formation is a key therapeutic target in osteoporosis. Runx2 is a runt domain transcription factor essential to osteoblast differentiation, bone remodeling, and fracture healing. Runx2 knockout mice exhibit a complete lack of ossification, while overexpression of this gene in transgenic mice results in an osteoporotic phenotype. Thus, RUNX2 is a good candidate for the genetic determination of osteoporosis. In this association study, the effects of the -330 G/T polymorphism in promoter 1 and the -1025 T/C polymorphism (rs7771980) in promoter 2 of RUNX2 were tested in relation to lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) in a cohort of 821 Spanish postmenopausal women. The minor allele frequencies for the two polymorphisms were 0.15 and 0.07, respectively. The two polymorphisms, located more than 90 kb apart, were not in linkage disequilibrium (D' = 0.27, r (2) = 0.028). In an ANCOVA test adjusting by weight, height, age, and years since menopause, the -330 G/T polymorphism was not associated with any of the phenotypes analyzed, while we found the -1025 T/C polymorphism to be associated with FN BMD (p = 0.001). In particular, individuals carrying the TC genotype had higher mean adjusted FN BMD values than those bearing the TT genotype. Our results highlight the importance of this RUNX2 promoter 2 polymorphism in FN BMD determination.
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Affiliation(s)
- Mariona Bustamante
- Department of Genetics, University of Barcelona, Av Diagonal, 645, E-08028, Barcelona, Spain
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Tsiridis E, Giannoudis PV. Transcriptomics and proteomics: advancing the understanding of genetic basis of fracture healing. Injury 2006; 37 Suppl 1:S13-9. [PMID: 16616752 DOI: 10.1016/j.injury.2006.02.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fracture healing is a complex physiological post-natal process, which involves the coordination of several different cell types. Exploring the orchestration of events and the simultaneous activation of osteogenesis and chondrogenesis that recapitulates mammalian embryological skeletal development seems to be not only sophisticated but also challenging. A large number of genes involved in the above process are known, but many more remain to be discovered. The functional characterisation of these genes promises to elucidate the repair process as well as skeletal abnormalities and aging. We here review the current knowledge on early and late gene expression during fracture healing, the genes so far associated with osteoblast and osteoclast differentiation, the BMP antagonists, and the Wnts signalling pathway.
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Affiliation(s)
- Eleftherios Tsiridis
- Trauma & Orthopaedic Surgery, School of Medicine, University of Leeds, and St. James's University Hospital, Beckett Street, Leeds LS9 7TF, UK
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Abe T, Nomura S, Nakagawa R, Fujimoto M, Kawase I, Naka T. Osteoblast differentiation is impaired in SOCS-1-deficient mice. J Bone Miner Metab 2006; 24:283-90. [PMID: 16816922 DOI: 10.1007/s00774-006-0685-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Accepted: 02/08/2006] [Indexed: 01/22/2023]
Abstract
The suppressor of cytokine signaling-1 (SOCS-1) is a cytokine-inducible intracellular molecule that inhibits excessive activation of the JAK-STAT-mediated signal cascade initiated by various stimuli. The smaller size of SOCS-1 knockout (KO) mice suggests the presence of skeletal abnormality caused by the disruption of the regulatory system in JAK-STAT signaling. In addition to macroscopic examination, peripheral quantitative computed tomography (pQCT), bone histomorphometrical analysis, and in situ hybridization were used to examine the skeletal properties of SOCS-1 KO mice. Moreover, differentiation of primary cultured osteoblasts was investigated. Distinct phosphorylation of STAT1 was detected in the SOCS-1 KO calvarial cells but was hardly detectable in wild-type (WT) mice. Undercalcified areas in the skulls and sternum, as well as comparatively thinner calcified areas of cortical bone, were found in SOCS-1 KO mice. pQCT analysis showed a marked decrease in salt content, whereas the mineralization activity of primary cultured calvarial cells strongly suggested significant impairment in osteoblasts of SOCS-1 KO mice. In situ hybridization analysis demonstrated that these mice expressed the early markers [type I collagen (COL-1) and osteonectin (ON)] and the mid-marker [osteopontin (OP)] at levels comparable with those seen in WT mice. However, a dramatic decrease was observed in the expression level of the late marker [osteocalcin (OC)] of osteoblasts. Our findings thus demonstrate that SOCS-1 regulates osteoblast differentiation in the later stage.
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Affiliation(s)
- Tatsuo Abe
- Department of Molecular Medicine, Graduate School of Osaka University Medical School, Suita, Japan
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Kanno T, Takahashi T, Ariyoshi W, Tsujisawa T, Haga M, Nishihara T. Tensile mechanical strain up-regulates Runx2 and osteogenic factor expression in human periosteal cells: implications for distraction osteogenesis. J Oral Maxillofac Surg 2005; 63:499-504. [PMID: 15789322 DOI: 10.1016/j.joms.2004.07.023] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE Distraction osteogenesis is now accepted as a standard treatment in oral and maxillofacial reconstructive surgery. In the process of bone regeneration with the application of strain, the periosteum might be very involved in osteogenesis. This study examined the effect of mechanical strain on periosteal cells and the implications for distraction osteogenesis. MATERIALS AND METHODS Periosteal cells were obtained from mandibular periosteum that was excised while extracting impacted wisdom teeth. Mechanical strain was applied using a specially designed apparatus with flexible silicon bottom chambers. The levels of mRNA of the osteoblast differentiation factor Runx2 (Cbfa1/AML3/Peb alpha A) and osteogenic factors were analyzed at different times using the reverse transcription-polymerase chain reaction method to evaluate the effect of the strain. RESULTS The periosteal cells expressed the osteogenic phenotype. The strain had a shaping effect on the cells. The application of tensile strain strongly activated the expression of osteogenic and angiogenic growth factors, and up-regulated the expression of Runx2, an osteoblast-specific transcription factor. CONCLUSION Tensile strain may initiate the differentiation of periosteal cells into osteogenic cells, inducing the expression of Runx2 in the process of bone regeneration. Therefore, the periosteum is profoundly involved in bone formation and regeneration, especially in distraction osteogenesis.
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Affiliation(s)
- Takahiro Kanno
- Department of Oral and Maxillofacial Surery, Kyushu Dental College, Fukuoka 803-8580, Japan.
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Fujita T, Azuma Y, Fukuyama R, Hattori Y, Yoshida C, Koida M, Ogita K, Komori T. Runx2 induces osteoblast and chondrocyte differentiation and enhances their migration by coupling with PI3K-Akt signaling. ACTA ACUST UNITED AC 2004; 166:85-95. [PMID: 15226309 PMCID: PMC2172136 DOI: 10.1083/jcb.200401138] [Citation(s) in RCA: 342] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Runx2 and phosphatidylinositol 3-kinase (PI3K)–Akt signaling play important roles in osteoblast and chondrocyte differentiation. We investigated the relationship between Runx2 and PI3K-Akt signaling. Forced expression of Runx2 enhanced osteoblastic differentiation of C3H10T1/2 and MC3T3-E1 cells and enhanced chondrogenic differentiation of ATDC5 cells, whereas these effects were blocked by treatment with IGF-I antibody or LY294002 or adenoviral introduction of dominant-negative (dn)–Akt. Forced expression of Runx2 or dn-Runx2 enhanced or inhibited cell migration, respectively, whereas the enhancement by Runx2 was abolished by treatment with LY294002 or adenoviral introduction of dn-Akt. Runx2 up-regulated PI3K subunits (p85 and p110β) and Akt, and their expression patterns were similar to that of Runx2 in growth plates. Treatment with LY294002 or introduction of dn-Akt severely diminished DNA binding of Runx2 and Runx2-dependent transcription, whereas forced expression of myrAkt enhanced them. These findings demonstrate that Runx2 and PI3K-Akt signaling are mutually dependent on each other in the regulation of osteoblast and chondrocyte differentiation and their migration.
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Affiliation(s)
- Takashi Fujita
- Department of Pharmacology, Setsunan University, Hirakata, Japan
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