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Cottrill E, Lazzari J, Pennington Z, Ehresman J, Schilling A, Dirckx N, Theodore N, Sciubba D, Witham T. Oxysterols as promising small molecules for bone tissue engineering: Systematic review. World J Orthop 2020; 11:328-344. [PMID: 32908817 PMCID: PMC7453739 DOI: 10.5312/wjo.v11.i7.328] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/08/2020] [Accepted: 07/01/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Bone tissue engineering is an area of continued interest within orthopaedic surgery, as it promises to create implantable bone substitute materials that obviate the need for autologous bone graft. Recently, oxysterols – oxygenated derivatives of cholesterol – have been proposed as a novel class of osteoinductive small molecules for bone tissue engineering. Here, we present the first systematic review of the in vivo evidence describing the potential therapeutic utility of oxysterols for bone tissue engineering.
AIM To systematically review the available literature examining the effect of oxysterols on in vivo bone formation.
METHODS We conducted a systematic review of the literature following PRISMA guidelines. Using the PubMed/MEDLINE, Embase, and Web of Science databases, we queried all publications in the English-language literature investigating the effect of oxysterols on in vivo bone formation. Articles were screened for eligibility using PICOS criteria and assessed for potential bias using an expanded version of the SYRCLE Risk of Bias assessment tool. All full-text articles examining the effect of oxysterols on in vivo bone formation were included. Extracted data included: Animal species, surgical/defect model, description of therapeutic and control treatments, and method for assessing bone growth. Primary outcome was fusion rate for spinal fusion models and percent bone regeneration for critical-sized defect models. Data were tabulated and described by both surgical/defect model and oxysterol employed. Additionally, data from all included studies were aggregated to posit the mechanism by which oxysterols may mediate in vivo bone formation.
RESULTS Our search identified 267 unique articles, of which 27 underwent full-text review. Thirteen studies (all preclinical) met our inclusion/exclusion criteria. Of the 13 included studies, 5 employed spinal fusion models, 2 employed critical-sized alveolar defect models, and 6 employed critical-sized calvarial defect models. Based upon SYRCLE criteria, the included studies were found to possess an overall “unclear risk of bias”; 54% of studies reported treatment randomization and 38% reported blinding at any level. Overall, seven unique oxysterols were evaluated: 20(S)-hydroxycholesterol, 22(R)-hydroxycholesterol, 22(S)-hydroxycholesterol, Oxy4/Oxy34, Oxy18, Oxy21/Oxy133, and Oxy49. All had statistically significant in vivo osteoinductive properties, with Oxy4/Oxy34, Oxy21/Oxy133, and Oxy49 showing a dose-dependent effect in some cases. In the eight studies that directly compared oxysterols to rhBMP-2-treated animals, similar rates of bone growth occurred in the two groups. Biochemical investigation of these effects suggests that they may be primarily mediated by direct activation of Smoothened in the Hedgehog signaling pathway.
CONCLUSION Present preclinical evidence suggests oxysterols significantly augment in vivo bone formation. However, clinical trials are necessary to determine which have the greatest therapeutic potential for orthopaedic surgery patients.
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Affiliation(s)
- Ethan Cottrill
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Julianna Lazzari
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Zach Pennington
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Jeff Ehresman
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Andrew Schilling
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Naomi Dirckx
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Nicholas Theodore
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Daniel Sciubba
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Timothy Witham
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
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Zhou S, Huang G, Chen G. Synthesis and biological activities of drugs for the treatment of osteoporosis. Eur J Med Chem 2020; 197:112313. [PMID: 32335412 DOI: 10.1016/j.ejmech.2020.112313] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/06/2020] [Accepted: 04/06/2020] [Indexed: 12/15/2022]
Abstract
Osteoporosis is an asymptomatic progressive disease. With the improvement of people's living standard and the aging of population, osteoporosis and its fracture have become one of the main diseases threatening the aging society. The serious medical and social burden caused by this has aroused wide public concern. Osteoporosis is listed as one of the three major diseases of the elderly. At present, the drugs for osteoporosis include bone resorption inhibitors and bone formation promoters. The purpose of these anti-osteoporosis drugs is to balance osteoblast bone formation and osteoclast bone resorption. With the development of anti-osteoporosis drugs, new anti osteoporosis drugs have been designed and synthesized. There are many kinds of new compounds with anti osteoporosis activity, but most of them are concentrated on the original drugs with anti osteoporosis activity, or the natural products with anti-osteoporosis activity are extracted from the natural products for structural modification to obtain the corresponding derivatives or analogues. These target compounds showed good ALP activity in vitro and in vivo, promoted osteoblast differentiation and mineralization, or had anti TRAP activity, inhibited osteoclast absorption. This work attempts to systematically review the studies on the synthesis and bioactivity of anti-osteoporosis drugs in the past 10 years. The structure-activity relationship was discussed, which provided a reasonable idea for the design and development of new anti-osteoporosis drugs.
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Affiliation(s)
- Shiyang Zhou
- Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou, 571158, China
| | - Gangliang Huang
- Active Carbohydrate Research Institute, Chongqing Key Laboratory of Green Synthesis and Application, College of Chemistry, Chongqing Normal University, Chongqing, 401331, China.
| | - Guangying Chen
- Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou, 571158, China.
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3
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Abstract
The 11 existing FDA-approved osteoporosis drug treatments include hormone replacement therapy, 2 SERMs (raloxifene and bazedoxifene), 5 inhibitors of bone-resorbing osteoclasts (4 bisphosphonates and anti-RANKL denosumab), 2 parathyroid hormone analogues (teriparatide and abaloparatide), and 1 WNT signaling enhancer (romosozumab). These therapies are effective and provide multiple options for patients and physicians. As the genomic revolution continues, potential novel targets for future drug development are identified. This review takes a wide perspective to describe potentially rewarding topics to explore, including knowledge of genes and pathways involved in bone cell metabolism, the utility of animal models, targeting drugs to bone, and ongoing advances in drug design and delivery.
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Screening for osteogenic activity in extracts from Irish marine organisms: The potential of Ceramium pallidum. PLoS One 2018; 13:e0207303. [PMID: 30485314 PMCID: PMC6261572 DOI: 10.1371/journal.pone.0207303] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 10/29/2018] [Indexed: 11/19/2022] Open
Abstract
Extracts and compounds derived from marine organisms have reportedly shown some osteogenic potential. As such, these bioactives may aid in the treatment of musculoskeletal conditions such as osteoporosis; helping to address inefficacies with current treatment options. In this study, 72 fractions were tested for their in vitro osteogenic activity using a human foetal osteoblast (hFOB) cell line and bone marrow derived mesenchymal stem cells (MSCs), focusing on their cytotoxic, proliferative and differentiation effects. Extracts dissolved in dimethyl sulfoxide and ethanol showed no significant osteogenic potential. However, two extracts derived from powder residues (left over from original organic extractions) caused a significant promotion of MSC differentiation. Bioactivity from powder residues derived from the epiphytic red algae Ceramium pallidum is described in detail to highlight its treatment potential. In vitro, C. pallidum was shown to promote MSC differentiation and extracellular matrix mineralisation. In vivo, this extract caused a significant increase in opercular bone growth of zebrafish larvae and a significant increase in bone density of regenerated adult caudal fins. Our findings therefore show the importance of continued screening efforts, particularly of novel extract sources, and the presence of bioactive compounds in C. pallidum extract.
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Bone Regenerative Engineering Using a Protein Kinase A-Specific Cyclic AMP Analogue Administered for Short Term. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2018. [DOI: 10.1007/s40883-018-0063-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Zhu Q, Gao J, Tian G, Tang Z, Tan Y. Adrenomedullin promotes the odontogenic differentiation of dental pulp stem cells through CREB/BMP2 signaling pathway. Acta Biochim Biophys Sin (Shanghai) 2017; 49:609-616. [PMID: 28541393 DOI: 10.1093/abbs/gmx053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Indexed: 01/25/2023] Open
Abstract
Adrenomedullin (AM) could promote the proliferation, the odontogenic differentiation and inhibit the apoptosis of dental pulp stem cells (DPSCs). AM in combination with DPSCs may be an effective strategy for pulp repair. However, there was no report on the mechanisms of AM in the odontogenic differentiation of DPSCs. The aim of this study is to investigate the molecular mechanisms through which AM promotes the odontogenic differentiation of DPSCs. Freshly extracted wisdom teeth were obtained from 27 patients. Cells at passage 3 to passage 5 were used in this study. DPSCs were treated with or without 10-7 M AM in Dulbecco's modified Eagle's medium culture, and then the accumulated calcium deposition was analyzed after 21 days by using alizarin red S staining. Odontogenic differentiation markers were determined by western blot analysis and quantitative real-time PCR. Western blot analysis results showed that AM had the capability of promoting the odontogenic differentiation of DPSCs and AM could enhance the phosphorylation of CREB and up-regulate the expression of BMP2. H89 is a CREB inhibitor which can inhibit the odontogenic differentiation of DPSCs through inhibiting the phosphorylation of CREB. Noggin could inhibit the odontogenic differentiation of DPSCs through inhibiting the activity of BMP2. These results indicated that AM could promote the odontogenic differentiation of DPSCs by upregulating the expression of BMP2 through the CREB signaling pathway.
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Affiliation(s)
- Qiang Zhu
- Department of Stomatology, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China
| | - Jianyong Gao
- Department of Stomatology, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China
| | - Gang Tian
- Department of Stomatology, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China
| | - Zhen Tang
- Department of Stomatology, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China
| | - Yinghui Tan
- Department of Stomatology, Xinqiao Hospital, the Third Military Medical University, Chongqing 400037, China
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Kumar P, Kushwaha P, Ahmad N, Maurya SW, Dev K, Khedgikar V, Siddiqui IR, Trivedi R, Maurya R. Design and synthesis of dalbergin analogues and evaluation of anti-osteoporotic activity. Bioorg Med Chem Lett 2017; 27:1765-1775. [DOI: 10.1016/j.bmcl.2017.02.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 02/08/2017] [Accepted: 02/24/2017] [Indexed: 01/13/2023]
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8
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Amrollahi P, Shah B, Seifi A, Tayebi L. Recent advancements in regenerative dentistry: A review. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 69:1383-90. [PMID: 27612840 DOI: 10.1016/j.msec.2016.08.045] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 08/04/2016] [Accepted: 08/18/2016] [Indexed: 12/20/2022]
Abstract
Although human mouth benefits from remarkable mechanical properties, it is very susceptible to traumatic damages, exposure to microbial attacks, and congenital maladies. Since the human dentition plays a crucial role in mastication, phonation and esthetics, finding promising and more efficient strategies to reestablish its functionality in the event of disruption has been important. Dating back to antiquity, conventional dentistry has been offering evacuation, restoration, and replacement of the diseased dental tissue. However, due to the limited ability and short lifespan of traditional restorative solutions, scientists have taken advantage of current advancements in medicine to create better solutions for the oral health field and have coined it "regenerative dentistry." This new field takes advantage of the recent innovations in stem cell research, cellular and molecular biology, tissue engineering, and materials science etc. In this review, the recently known resources and approaches used for regeneration of dental and oral tissues were evaluated using the databases of Scopus and Web of Science. Scientists have used a wide range of biomaterials and scaffolds (artificial and natural), genes (with viral and non-viral vectors), stem cells (isolated from deciduous teeth, dental pulp, periodontal ligament, adipose tissue, salivary glands, and dental follicle) and growth factors (used for stimulating cell differentiation) in order to apply tissue engineering approaches to dentistry. Although they have been successful in preclinical and clinical partial regeneration of dental tissues, whole-tooth engineering still seems to be far-fetched, unless certain shortcomings are addressed.
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Affiliation(s)
- Pouya Amrollahi
- Helmerich Advanced Technology Research Center, School of Material Science and Engineering, Oklahoma State University, Tulsa, OK 74106, USA
| | - Brinda Shah
- Marquette University School of Dentistry, Milwaukee, WI 53201, USA
| | - Amir Seifi
- Marquette University School of Dentistry, Milwaukee, WI 53201, USA
| | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI 53201, USA; Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK.
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9
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de Matos MBC, Puga AM, Alvarez-Lorenzo C, Concheiro A, Braga MEM, de Sousa HC. Osteogenic poly(ε-caprolactone)/poloxamine homogeneous blends prepared by supercritical foaming. Int J Pharm 2014; 479:11-22. [PMID: 25541145 DOI: 10.1016/j.ijpharm.2014.12.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 12/17/2014] [Accepted: 12/19/2014] [Indexed: 11/16/2022]
Abstract
Homogeneous poly(ε-caprolactone) (PCL) and poloxamines (PLXs) porous blends were prepared using a supercritical carbon dioxide-assisted foaming/mixing (SFM) approach aiming to obtain cytocompatible implantable materials presenting tunable morphologies, bioerosion rates, bioactive molecules release and osteogenic features. Pure PCL, pure PLXs (T908 and T1107 varieties) and three distinct PCL:PLX 75:25, 50:50, 25:75% w/w blends, with and without the osteogenic and angiogenic bioactive molecule simvastatin were processed at constant pressure of 20 MPa and temperature of 40 °C or 43 °C, for T1107 and T908, respectively. Obtained porous blends were characterized applying a wide range of techniques and in vitro methods. Calorimetric analysis showed that hydrophilic T908 and T1107 PLXs are miscible with PCL for all tested compositions. Prepared PCL:PLX porous blends rapidly lost mass when immersed into phosphate buffer pH 7.4 due to PLXs dissolution and then went through slow and almost constant erosion rates for the subsequent weeks due to PCL slow hydrolytic degradation, which explains the rapid initial release of simvastatin and its subsequent sustained release for longer periods of time. PCL and PCL:PLX 75:25% w/w porous blends, containing or not simvastatin, showed a high cytocompatibility with SAOS-2 cells. In addition, prepared biomaterials promoted mesenchymal stem cells proliferation and their differentiation into osteoblasts. Overall, obtained results showed novel possibilities of addressing local treatment of small bone defects/fractures using highly porous PCL:PLX homogeneous blends.
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Affiliation(s)
- Maria B C de Matos
- CIEPQPF, Chemical Engineering Department, FCTUC, University of Coimbra, Rua Sílvio Lima, Pólo II-Pinhal de Marrocos, 3030-790 Coimbra, Portugal
| | - Ana M Puga
- Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain; Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Carmen Alvarez-Lorenzo
- Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain.
| | - Angel Concheiro
- Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Mara E M Braga
- CIEPQPF, Chemical Engineering Department, FCTUC, University of Coimbra, Rua Sílvio Lima, Pólo II-Pinhal de Marrocos, 3030-790 Coimbra, Portugal.
| | - Hermínio C de Sousa
- CIEPQPF, Chemical Engineering Department, FCTUC, University of Coimbra, Rua Sílvio Lima, Pólo II-Pinhal de Marrocos, 3030-790 Coimbra, Portugal.
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Khan MF, Dev K, Lahiri S, Dixit M, Trivedi R, Singh D, Maurya R. Osteogenic activity of natural diterpenoids isolated from Cupressus sempervirens fruits in calvarial derived osteoblast cells via differentiation and mineralization. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:1794-1800. [PMID: 25481392 DOI: 10.1016/j.phymed.2014.09.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 08/21/2014] [Accepted: 09/13/2014] [Indexed: 06/04/2023]
Abstract
The aim of the present study was to investigate the antiosteoporotic activity of four structurally related diterpenoids: sugiol (1), trans-communic acid (2), 15-acetoxy imbricatolic acid (3) and imbricatolic acid (4). Their osteogenic effect was evaluated by using validated models including alkaline phosphatase (ALP) assay, mineralization assay and expression of osteogenic genes-bone morphogenetic protein-2 (BMP-2) and osteoblast transcription factor (RUNX2) - in primary calvarial cultures harvested from neonatal mice. Among them, compound 1 at a dose of 1.0 mg/kg body weight exhibited significant osteoprotective effects and did not show uterine estrogenicity at the same dose. Additionally, compound 1 treatment led to improved biomechanical properties as exhibited by increased power, energy and stiffness in femoral bones compared to untreated Ovx animals. Since osteoporotic compression fracture correlates with the mechanical characteristics of trabecular bone, so that it could effectively reduce the risk of this type of fracture by improving trabecular micro architecture in postmenopausal women. Therefore, our findings proposed that diterpenoids may be useful new chemical agents in the treatment of diseases associated with bone loss.
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Affiliation(s)
- Mohammad Faheem Khan
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Kapil Dev
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Shibani Lahiri
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Manisha Dixit
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Ritu Trivedi
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Divya Singh
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Rakesh Maurya
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031, India.
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11
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Patil S, Paul S. A comprehensive review on the role of various materials in the osteogenic differentiation of mesenchymal stem cells with a special focus on the association of heat shock proteins and nanoparticles. Cells Tissues Organs 2014; 199:81-102. [PMID: 25401759 DOI: 10.1159/000362226] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2014] [Indexed: 11/19/2022] Open
Abstract
Mesenchymal stem cells (MSCs) have important roles in the area of regenerative medicine and clinical applications due to their pluripotent nature. Osteogenic differentiation of MSCs has been studied extensively using various stimulants to develop models of bone repair. There are several factors that enhance the differentiation of MSCs into bone tissues. This review focuses on the effects of various inducers on the osteoblast differentiation of MSCs at different stages of cellular development. We discuss the various growth factors, hormones, vitamins, cytokines, chemical stimulants, and mechanical forces applied in bioreactors that play an essential role in the proliferation, differentiation, and matrix mineralization of stem cells during osteogenesis. Various nanoparticles have also been used recently for the same purpose and the results are promising. Moreover, we review the role of various stresses, including thermal stress, and the subsequent involvement of heat shock proteins as inducers of the proliferation and differentiation of osteoblasts. We also report how various proteasome inhibitors have been shown to induce proliferation and osteogenic differentiation of MSCs in a number of cases. In this communication, the role of peptide-based scaffolds in osteoblast proliferation and differentiation is also reviewed. Based on the reviewed information, this article proposes novel possibilities for the enhancement of proliferation, differentiation, and migration of osteoblasts from MSCs. © 2014 S. Karger AG, Basel.
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Affiliation(s)
- Supriya Patil
- Structural Biology and Nanomedicine Laboratory, Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Rourkela, India
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12
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Chen S, Ryan DA, Dwyer MA, Cashman JR. Synergistic effect of Wnt modulatory small molecules and an osteoinductive ceramic on C2C12 cell osteogenic differentiation. Bone 2014; 67:109-21. [PMID: 24998670 DOI: 10.1016/j.bone.2014.06.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 06/15/2014] [Accepted: 06/25/2014] [Indexed: 01/25/2023]
Abstract
Although osteoinductive ceramics can induce osteoblast differentiation in vitro and bone regeneration in vivo, their effects rely solely on the limited number of endogenous stem cells. More recently, ceramic carriers seeded with culture-expanded stem cells have been reported as implants capable of in vivo bone formation. However, effective and safe signaling agents that promote cell differentiation to the osteogenic lineage are still needed. In the present report, two osteogenic small-molecules THQ-1a and PP-9 were identified by testing a series of compounds for Runx2 and BMP2 expression in C2C12 cells. Compounds THQ-1a and PP-9 modulated Wnt signaling and enhanced the expression of molecular markers of osteoblast differentiation. To probe the utility of these compounds for use with ceramic cell implants, the effect of THQ-1a and PP-9 on C2C12 cell osteogenic differentiation was investigated in the presence of a tricalcium phosphate (TCP) ceramic. The effect of THQ-1a and PP-9 on markers such as Osteocalcin and Collagen I was significantly increased in the presence of TCP ceramic. Additionally, THQ-1a or PP-9 in the presence of TCP ceramic gave a synergistic increase in alkaline phosphatase activity in the differentiation of C2C12 cells. Taken together, the results suggest an approach to directing cell lineage commitment for bone regeneration by the application of small-molecule osteogenic agents to cells in the presence of osteoinductive ceramics.
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Affiliation(s)
- Sigeng Chen
- The Human BioMolecular Research Institute, San Diego, CA 92121, USA
| | - Daniel A Ryan
- The Human BioMolecular Research Institute, San Diego, CA 92121, USA.
| | - Mary A Dwyer
- The Human BioMolecular Research Institute, San Diego, CA 92121, USA
| | - John R Cashman
- The Human BioMolecular Research Institute, San Diego, CA 92121, USA
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13
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Delivery of small molecules for bone regenerative engineering: preclinical studies and potential clinical applications. Drug Discov Today 2014; 19:794-800. [PMID: 24508820 DOI: 10.1016/j.drudis.2014.01.012] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 01/01/2014] [Accepted: 01/31/2014] [Indexed: 12/20/2022]
Abstract
Stimulation of bone regeneration using growth factors is a promising approach for musculoskeletal regenerative engineering. However, common limitations with protein growth factors, such as high manufacturing costs, protein instability, contamination issues, and unwanted immunogenic responses of the host reduce potential clinical applications. New strategies for bone regeneration that involve inexpensive and stable small molecules can obviate these problems and have a significant impact on the treatment of skeletal injury and diseases. Over the past decade, a large number of small molecules with the potential of regenerating skeletal tissue have been reported in the literature. Here, we review this literature, paying specific attention to the prospects for small molecule-based bone-regenerative engineering. We also review the preclinical study of small molecules associated with bone regeneration.
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Lo KWH, Kan HM, Laurencin CT. Short-term administration of small molecule phenamil induced a protracted osteogenic effect on osteoblast-like MC3T3-E1 cells. J Tissue Eng Regen Med 2013; 10:518-26. [PMID: 23913855 DOI: 10.1002/term.1786] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 04/13/2013] [Accepted: 05/27/2013] [Indexed: 12/26/2022]
Abstract
Sustained administration (21-day treatment) of the small molecule phenamil has been proposed as an alternative osteogenic factor when used in conjunction with a biodegradable scaffold for in vitro osteogenesis. While promising, the major issue associated with small molecules is non-specific cytotoxicity. The aim of this study was to minimize the side-effects from small-molecule drugs by reducing the frequency of administration. Toward this goal, we investigated whether a shorter phenamil treatment is sufficient to induce in vitro osteogenesis. We compared the effects of short-term (12 h) and continuous treatments of phenamil on osteoblastic differentiation and mineralization. Alkaline phosphatase (ALP) and osteopontin (OPN) activity were used as markers for osteoblastic differentiation. Measurement of the calcium content of the extracellular matrix was used as the hallmark for in vitro bone formation after 21 days of culture. Our findings revealed that both short and continuous phenamil treatment triggers osteoblastic differentiation and mineralization of MC3T3-E1 cells on a biodegradable polymeric scaffold composed of polylactic-co-glycolic acid (PLAGA) at the same time points. In addition, in order to fabricate a phenamil-loaded PLAGA scaffold, the small molecule phenamil was physically absorbed onto the surface of scaffolds and the bioactivity of the loaded scaffolds was evaluated. Furthermore, biochemical analysis indicated that short phenamil treatment of cells was accompanied by upregulation in protein expression of integrin α5, p125(FAK) and phosphorylation of CREB. These effects may contribute to the downstream signalling cascade necessary for osteogenesis, and such responses may account for our observed protracted osteogenic differentiation in vitro. Copyright © 2013 John Wiley & Sons, Ltd.
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Affiliation(s)
- Kevin W-H Lo
- Institute for Regenerative Engineering, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,The Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,Department of Medicine, Division of Endocrinology, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,Department of Biomedical Engineering, University of Connecticut, School of Engineering, Storrs, CT, USA
| | - Ho Man Kan
- Department of Orthopedic Surgery, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,Institute for Regenerative Engineering, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,The Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA
| | - Cato T Laurencin
- Department of Orthopedic Surgery, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,Institute for Regenerative Engineering, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,The Raymond and Beverly Sackler Center for Biomedical, Biological, Physical and Engineering Sciences, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA.,Department of Chemical, Materials and Biomolecular Engineering, University of Connecticut, School of Engineering, Storrs, CT, USA.,Department of Biomedical Engineering, University of Connecticut, School of Engineering, Storrs, CT, USA
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Lo KWH, Ashe KM, Kan HM, Laurencin CT. The role of small molecules in musculoskeletal regeneration. Regen Med 2013; 7:535-49. [PMID: 22817627 DOI: 10.2217/rme.12.33] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The uses of bone morphogenetic proteins and parathyroid hormone therapeutics are fraught with several fundamental problems, such as cost, protein stability, immunogenicity, contamination and supraphysiological dosage. These downsides may effectively limit their more universal use. Therefore, there is a clear need for alternative forms of biofactors to obviate the drawbacks of protein-based inductive factors for bone repair and regeneration. Our group has studied small molecules with the capacity to regulate osteoblast differentiation and mineralization because their inherent physical properties minimize limitations observed in protein growth factors. For instance, in general, small molecule inducers are usually more stable, highly soluble, nonimmunogenic, more affordable and require lower dosages. Small molecules with the ability to induce osteoblastic differentiation may represent the next generation of bone regenerative medicine. This review describes efforts to develop small molecule-based biofactors for induction, paying specific attention to their novel roles in bone regeneration.
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Affiliation(s)
- Kevin W-H Lo
- Institute for Regenerative Engineering, University of Connecticut Health Center, School of Medicine, Farmington, CT 06030, USA
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16
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Lo KWH, Ulery BD, Kan HM, Ashe KM, Laurencin CT. Evaluating the feasibility of utilizing the small molecule phenamil as a novel biofactor for bone regenerative engineering. J Tissue Eng Regen Med 2012; 8:728-36. [PMID: 22815259 DOI: 10.1002/term.1573] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 05/17/2012] [Accepted: 06/12/2012] [Indexed: 01/30/2023]
Abstract
Osteoblast cell adhesion and differentiation on biomaterials are important achievements necessary for implants to be useful in bone regenerative engineering. Recombinant bone morphogenetic proteins (BMPs) have been shown to be important for these processes; however, there are many challenges associated with the widespread use of these proteins. A recent report demonstrated that the small molecule phenamil, a diuretic derivative, was able to induce osteoblast differentiation and mineralization in vitro via the canonical BMP signalling cascade (Park et al., 2009). In this study, the feasibility of using phenamil as a novel biofactor in conjunction with a biodegradable poly(lactide-co-glycolide acid) (PLAGA) polymeric scaffold for engineering bone tissue was evaluated. The in vitro cellular behaviour of osteoblast-like MC3T3-E1 cells cultured on PLAGA scaffolds in the presence of phenamil at 10 μM were characterized with regard to initial cell adhesion, proliferation, alkaline phosphatase (ALP) activity and matrix mineralization. The results demonstrate that phenamil supported cell proliferation, promoted ALP activity and facilitated matrix mineralization of osteoblast-like MC3T3-E1 cells. Moreover, in this study, we found that phenamil promoted integrin-mediated cell adhesion on PLAGA scaffolds. It was also shown that phenamil encapsulated within porous, microsphere PLAGA scaffolds retained its osteogenic activity upon release. Based on these findings, the small molecule phenamil has the potential to serve as a novel biofactor for the repair and regeneration of bone tissues.
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Affiliation(s)
- Kevin W-H Lo
- Institute for Regenerative Engineering, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA; Department of Medicine, Division of Endocrinology, University of Connecticut Health Center, School of Medicine, Farmington, CT, USA
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Law MC, Wong KC, Pang WY, Wong MS, Chan TH. Chemical synthesis and biological study of 4β-carboxymethyl-epiafzelechin acid, an osteoprotective compound from the rhizomes of Drynaria fortunei. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20082a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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18
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Dao TT, Lee KY, Jeong HM, Nguyen PH, Tran TL, Thuong PT, Nguyen BT, Oh WK. ent-Kaurane diterpenoids from Croton tonkinensis stimulate osteoblast differentiation. JOURNAL OF NATURAL PRODUCTS 2011; 74:2526-2531. [PMID: 22085418 DOI: 10.1021/np200667f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Four new ent-kaurane diterpenoids (1-4) were isolated from the leaves of Croton tonkinensis by bioactivity-guided fractionation using an in vitro osteoblast differentiation assay. Their structures were identified as ent-11β-acetoxykaur-16-en-18-ol (1), ent-11α-hydroxy-18-acetoxykaur-16-ene (2), ent-14β-hydroxy-18-acetoxykaur-16-ene (3), and ent-7α-hydroxy-18-acetoxykaur-16-ene (4). Compounds 1-4 significantly increased alkaline phosphatase activity and osteoblastic gene promoter activity. Compounds 1-3 also increased the levels of ALP and collagen type I alpha mRNA in C2C12 cells in a dose-dependent manner. These results suggest that ent-kaurane diterpenoids from C. tonkinensis have a direct stimulatory effect on osteoblast differentiation and may be potential therapeutic molecules against bone diseases such as osteoporosis.
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Affiliation(s)
- Trong-Tuan Dao
- BK21 Project Team, College of Pharmacy, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
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Yu L, van der Valk M, Cao J, Han CYE, Juan T, Bass MB, Deshpande C, Damore MA, Stanton R, Babij P. Sclerostin expression is induced by BMPs in human Saos-2 osteosarcoma cells but not via direct effects on the sclerostin gene promoter or ECR5 element. Bone 2011; 49:1131-40. [PMID: 21890009 DOI: 10.1016/j.bone.2011.08.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 08/09/2011] [Accepted: 08/14/2011] [Indexed: 12/15/2022]
Abstract
Sclerostin is a secreted inhibitor of Wnt signaling and plays an essential role in the regulation of bone mass. The expression of sclerostin is largely restricted to osteocytes although its mode of transcriptional regulation is not well understood. We observed regulated expression of sclerostin mRNA and protein that was directly correlated with the mineralization response in cultured human Saos-2 osteosarcoma cells and rat primary calvarial cells. Sclerostin mRNA and protein levels were increased following treatment of cells with BMP2, BMP4 and BMP7. Analysis of deletion mutants from the -7.4 kb upstream region of the human sclerostin promoter did not reveal any specific regions that were responsive to BMPs, Wnt3a, PTH, TGFβ1 or Activin A in Saos-2 cells. The downstream ECR5 element did not show enhancer activity in Saos-2 cells and also was not affected when Saos-2 cells were treated with BMPs or PTH. Genome-wide microarray analysis of Saos-2 cells treated with BMP2 showed significant changes in expression of several transcription factors with putative consensus DNA binding sites in the region of the sclerostin promoter. However, whereas most factors tested showed either a range of inhibitory activity (DLX family, MSX2, HEY1, SMAD6/7) or lack of activity on the sclerostin promoter including SMAD9, only MEF2B showed a positive effect on both the promoter and ECR5 element. These results suggest that the dramatic induction of sclerostin gene expression by BMPs in Saos-2 cells occurs indirectly and is associated with late stage differentiation of osteoblasts and the mineralization process.
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MESH Headings
- Activins/pharmacology
- Adaptor Proteins, Signal Transducing
- Animals
- Bone Morphogenetic Proteins/genetics
- Bone Morphogenetic Proteins/metabolism
- Bone Morphogenetic Proteins/pharmacology
- Calcification, Physiologic/drug effects
- Calcification, Physiologic/genetics
- Cell Line, Tumor
- Enhancer Elements, Genetic/genetics
- Gene Expression Regulation, Neoplastic/drug effects
- Genetic Markers/genetics
- Humans
- Osteoblasts/drug effects
- Osteoblasts/metabolism
- Osteogenesis/drug effects
- Osteogenesis/genetics
- Osteosarcoma/genetics
- Osteosarcoma/pathology
- Parathyroid Hormone/pharmacology
- Promoter Regions, Genetic/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transforming Growth Factor beta1/pharmacology
- Wnt3A Protein/pharmacology
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Affiliation(s)
- Longchuan Yu
- Department of Metabolic Disorders, One Amgen Center Drive, Thousand Oaks, CA 91320, USA.
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20
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Zhang R, Edwards JR, Ko SY, Dong S, Liu H, Oyajobi BO, Papasian C, Deng HW, Zhao M. Transcriptional regulation of BMP2 expression by the PTH-CREB signaling pathway in osteoblasts. PLoS One 2011; 6:e20780. [PMID: 21695256 PMCID: PMC3111437 DOI: 10.1371/journal.pone.0020780] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Accepted: 05/09/2011] [Indexed: 11/18/2022] Open
Abstract
Intermittent application of parathyroid hormone (PTH) has well established anabolic effects on bone mass in rodents and humans. Although transcriptional mechanisms responsible for these effects are not fully understood, it is recognized that transcriptional factor cAMP response element binding protein (CREB) mediates PTH signaling in osteoblasts, and that there is a communication between the PTH-CREB pathway and the BMP2 signaling pathway, which is important for osteoblast differentiation and bone formations. These findings, in conjunction with putative cAMP response elements (CREs) in the BMP2 promoter, led us to hypothesize that the PTH-CREB pathway could be a positive regulator of BMP2 transcription in osteoblasts. To test this hypothesis, we first demonstrated that PTH signaling activated CREB by phosphorylation in osteoblasts, and that both PTH and CREB were capable of promoting osteoblastic differentiation of primary mouse osteoblast cells and multiple rodent osteoblast cell lines. Importantly, we found that the PTH-CREB signaling pathway functioned as an effective activator of BMP2 expression, as pharmacologic and genetic modulation of PTH-CREB activity significantly affected BMP2 expression levels in these cells. Lastly, through multiple promoter assays, including promoter reporter deletion, mutation, chromatin immunoprecipitation (ChIP), and electrophoretic mobility shift assay (EMSA), we identified a specific CRE in the BMP2 promoter which is responsible for CREB transactivation of the BMP2 gene in osteoblasts. Together, these results demonstrate that the anabolic function of PTH signaling in bone is mediated, at least in part, by CREB transactivation of BMP2 expression in osteoblasts.
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Affiliation(s)
- Rongrong Zhang
- Department of Biostatistics and Bioinformatics, Tulane University, New Orleans, Louisiana, United States of America
| | - James R. Edwards
- Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Seon-Yle Ko
- School of Dentistry, Dankook University, Cheonan, Choongnam, Korea
| | - Shanshan Dong
- Department of Biostatistics and Bioinformatics, Tulane University, New Orleans, Louisiana, United States of America
| | - Hongbin Liu
- Department of Biostatistics and Bioinformatics, Tulane University, New Orleans, Louisiana, United States of America
| | - Babatunde O. Oyajobi
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Christopher Papasian
- Department of Basic Medical Sciences, University of Missouri – Kansas City, Kansas City, Missouri, United States of America
| | - Hong-Wen Deng
- Department of Biostatistics and Bioinformatics, Tulane University, New Orleans, Louisiana, United States of America
| | - Ming Zhao
- Department of Biostatistics and Bioinformatics, Tulane University, New Orleans, Louisiana, United States of America
- Department of Cellular and Molecular Biology, Tulane University, New Orleans, Louisiana, United States of America
- * E-mail:
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21
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Lo KWH, Kan HM, Ashe KM, Laurencin CT. The small molecule PKA-specific cyclic AMP analogue as an inducer of osteoblast-like cells differentiation and mineralization. J Tissue Eng Regen Med 2011; 6:40-8. [PMID: 21312339 DOI: 10.1002/term.395] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 11/11/2010] [Indexed: 12/21/2022]
Abstract
Osteoblastic differentiation is an important landmark for bone formation, bone repair and regeneration; however, it is a very complex process controlled by different signalling mechanisms. Several groups have reported that the cyclic adenosine monophosphate (cAMP) signalling system is responsible for regulating osteoblast cell differentiation. Nonetheless, to date, the principle role of the cAMP molecules related to this process remains controversial. Moreover, the underlying cAMP-dependent signalling cascade governing the osteoblastic differentiation has not been clarified. In this study we investigated the roles of the cAMP-dependent protein kinase A (PKA) signalling in proliferation, differentiation and mineralization of osteoblast-like MC3T3-E1 cells, using the PKA-specific small molecule cAMP analogue, 6-Bnz-cAMP, at 100 µM. Alkaline phosphatase (ALP) activity, runt transcription factor 2 (Runx2), osteopontin (OPN) and osteocalcin (OCN) protein expressions were used as osteoblast-specific markers to demonstrate osteoblastic differentiation. Further, calcium measurement of the extracellular matrix was employed as the hallmark of matrix mineralization or calcification. We report here that activation of PKA by the small molecule 6-Bnz-cAMP induces osteoblastic differentiation and matrix mineralization of osteoblast-like MC3T3-E1 cells. Moreover, 6-Bnz-cAMP does not induce cytotoxicity to the cells, as revealed by our cell proliferation studies. Therefore, based on these findings, we propose that the PKA-specific small molecule 6-Bnz-cAMP may serve as a novel bone-inducing growth factor for repairing and regenerating bone tissues during bone-regenerative engineering.
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Affiliation(s)
- Kevin W-H Lo
- Department of Orthopaedic Surgery, Institute for Regenerative Engineering, University of Connecticut Health Center, Farmington, CT, USA
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22
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Allen JG, Fotsch C, Babij P. Emerging Targets in Osteoporosis Disease Modification. J Med Chem 2010; 53:4332-53. [PMID: 20218623 DOI: 10.1021/jm9018756] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- John G. Allen
- Chemistry Research and Discovery, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, California 91320
| | - Christopher Fotsch
- Chemistry Research and Discovery, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, California 91320
| | - Philip Babij
- Metabolic Disorders, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, California 91320
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Egusa H, Saeki M, Doi M, Fukuyasu S, Matsumoto T, Kamisaki Y, Yatani H. A Small-molecule Approach to Bone Regenerative Medicine in Dentistry. J Oral Biosci 2010. [DOI: 10.1016/s1349-0079(10)80039-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Allen JG, Lee MR, Han CYE, Scherrer J, Flynn S, Boucher C, Zhao H, O’Connor AB, Roveto P, Bauer D, Graceffa R, Richards WG, Babij P. Identification of small molecule inhibitors of proline-rich tyrosine kinase 2 (Pyk2) with osteogenic activity in osteoblast cells. Bioorg Med Chem Lett 2009; 19:4924-8. [DOI: 10.1016/j.bmcl.2009.07.084] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 07/15/2009] [Accepted: 07/17/2009] [Indexed: 11/17/2022]
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