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Sun Q, Huang J, Tian J, Lv C, Li Y, Yu S, Liu J, Zhang J. Key Roles of Gli1 and Ihh Signaling in Craniofacial Development. Stem Cells Dev 2024; 33:251-261. [PMID: 38623785 DOI: 10.1089/scd.2024.0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024] Open
Abstract
The Hedgehog (Hh) signaling pathway orchestrates its influence through a dynamic interplay of Hh proteins, the cell surface receptor Ptch1, Smo, and Gli transcription factors, contributing to a myriad of developmental events. Indian Hedgehog (Ihh) and Gli zinc finger transcription factor 1 (Gli1) play crucial roles in developmental regulation within the Hh signaling pathway. Ihh regulates chondrocyte proliferation, differentiation, and bone formation, impacting the development of cranial bones, cartilage, and the temporomandibular joint (TMJ). Losing Ihh results in cranial bone malformation and decreased ossification and affects the formation of cranial base cartilage unions, TMJ condyles, and joint discs. Gli1 is predominantly expressed during early craniofacial development, and Gli1+ cells are identified as the primary mesenchymal stem cells (MSCs) for craniofacial bones, crucial for cell differentiation and morphogenesis. In addition, a complex mutual regulatory mechanism exists between Gli1 and Ihh, ensuring the normal function of the Hh signaling pathway by directly or indirectly regulating each other's expression levels. And the interaction between Ihh and Gli1 significantly impacts the normal development of craniofacial tissues. This review summarizes the pivotal roles of Gli1 and Ihh in the intricate landscape of mammalian craniofacial development and outlines the molecular regulatory mechanisms and intricate interactions governing the growth of bone and cartilage exhibited by Gli1 and Ihh, which provides new insights into potential therapeutic strategies for related diseases or researches of tissue regeneration.
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Affiliation(s)
- Qi Sun
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
- Yunnan Key Laboratory of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Jie Huang
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
- Yunnan Key Laboratory of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Jingjun Tian
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Changhai Lv
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Yanhong Li
- Department of Preventive Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Siyuan Yu
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Juan Liu
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
- Department of Preventive Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
| | - Jun Zhang
- Department of Pediatric Dentistry, School and Hospital of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
- Yunnan Key Laboratory of Stomatology, Kunming Medical University, Kunming, Yunnan, Republic of China
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Kitami M, Kaku M, Thant L, Maeda T. A loss of primary cilia by a reduction in mTOR signaling correlates with age-related deteriorations in condylar cartilage. GeroScience 2024:10.1007/s11357-024-01143-x. [PMID: 38526843 DOI: 10.1007/s11357-024-01143-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/16/2024] [Indexed: 03/27/2024] Open
Abstract
Age-related deterioration of condylar cartilage is an etiological factor in temporomandibular joint-osteoarthritis (TMJ-OA). However, its underlying mechanism remains unknown. Therefore, we examined age-related changes and the relationship between mTOR signaling and primary cilia in condylar cartilage to determine the intrinsic mechanisms of age-related TMJ-OA. Age-related morphological changes were analyzed using micro-computed tomography and safranin O-stained histological samples of the mandibular condyle of C57BL/6J mice (up to 78 weeks old). Immunohistochemistry was used to assess the activity of mTOR signaling, primary cilia frequency, and Golgi size of condylar chondrocytes. Four-week-old mice receiving an 11-week series of intraperitoneal injections of rapamycin, a potent mTOR signaling inhibitor, were used for the histological evaluation of the condylar cartilage. The condylar cartilage demonstrated an age-related reduction in cartilage area, including chondrocyte size, cell density, and cell size distribution. The Golgi size, primary cilia frequency, and mTOR signaling also decreased with age. Rapamycin injections resulted in both diminished cartilage area and cell size, resembling the phenotypes observed in aged mice. Rapamycin-injected mice also exhibited a smaller Golgi size and lower primary cilia frequency in condylar cartilage. We demonstrated that a loss of primary cilia due to a decline in mTOR signaling was correlated with age-related deteriorations in condylar cartilage. Our findings provide new insights into the tissue homeostasis of condylar cartilage, contributing to understanding the etiology of age-related TMJ-OA.
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Affiliation(s)
- Megumi Kitami
- Division of Dental Pharmacology, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.
- Center for Advanced Oral Science, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.
| | - Masaru Kaku
- Division of Bio-Prosthodontics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.
| | - Lay Thant
- Division of Dental Pharmacology, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
- Center for Advanced Oral Science, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Takeyasu Maeda
- Center for Advanced Oral Science, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
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Masuyama T, Sato I, Ueda Y, Kawata S, Yakura T, Itoh M. Neurotransmission, Vasculogenesis, and Osteogenesis Activities are Altered in the Aging Temporomandibular Joint of the Senescence-Accelerated Prone 8 Mouse Model. J Oral Maxillofac Surg 2024; 82:19-35. [PMID: 37832598 DOI: 10.1016/j.joms.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 10/15/2023]
Abstract
BACKGROUND Alterations in neurotransmission, vasculogenesis, and osteogenesis pathways that may play pivotal roles in age-related changes in the temporomandibular joint (TMJ) are poorly understood. PURPOSE This study aimed to measure the associations between gene and protein profiles in senescence-accelerated prone 8 (SAMP8) mice. STUDY DESIGN The investigators designed and used 3 groups of 2 mouse models: 1) early aging SAMP8 at 24 weeks of age and control SAMR1 at 12 and 24 weeks (each stage n = 12). PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE The independent variable was investigated using 3 mouse models: an early aging mouse model and a control mouse model (12 and 24 weeks). MAIN OUTCOME VARIABLE(S) The primary outcome variables were CGRP, VEGF-A, CD31, LYVE-1, osteocalcin, osteopontin, type I and II collagen, and MMP-2. The secondary outcome variables were histological characteristics. COVARIATES Not applicable. ANALYSES The gene and protein expression profiles of neurotransmitters, vasculogenesis, and osteogenesis were identified by quantitative real-time polymerase chain reaction and dot blot analysis, respectively. The cellular localization of these events was verified by in situ hybridization and immunohistochemistry. Bivariate statistics were computed for each of the outcome variables. Statistical significance was set to a P value < .05. RESULTS The expression of CGRP mRNA in the bony mandibular condyle (BMC) of SAMP8 mice (SAMP8, 3.3 ± 0.39 vs SAMR1, 0.001 ± 0.0001) was high at 24 weeks of age (24 weeks) (P < .001). Higher numbers of cells positive percentage for CGRP (MF, SAMP8, 28.67 ± 1.60 vs SAMR 1, 6.36 ± 1.10; CMC, 27.5 ± 2.12 vs 9.00 ± 1.21; BMC, 31.31 ± 2.81 vs 7.85 ± 1.14) and VEGF-A (MF, 34.43 ± 2.45 vs 14.01 ± 1.28; MD, 32.69 ± 1.86 vs 8.00 ± 0.91; CMC, 36.60 ± 2.05 vs 14.19 ± 1.25 BMC 36.49 vs 12.59 ± 1.41) antibodies were found in the 24 weeks TMJ (P < .01). CONCLUSIONS AND RELEVANCE The neurotransmitter, vasculogenesis, and osteogenesis pathways are associated with TMJ aging in the SAMP8 mouse model. In the future, the SAMP8 mouse model may prove to be a robust model for identifying molecular and biochemical events underlying the effects of feeding, occlusal changes, and tooth loss in the aging TMJ.
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Affiliation(s)
| | - Iwao Sato
- Visiting Professor, Department of Anatomy, Tokyo Medical University, Tokyo, Japan.
| | - Yoko Ueda
- Research, Associate Professor, Department of Anatomy, Tokyo Medical University, Tokyo, Japan
| | - Shinichi Kawata
- Assistant Professor, Department of Anatomy, Tokyo Medical University, Tokyo, Japan
| | - Tomiko Yakura
- Associate Professor, Department of Anatomy, Tokyo Medical University, Tokyo, Japan
| | - Masahiro Itoh
- Chief Professor, Department of Anatomy, Tokyo Medical University, Tokyo, Japan
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El-Qashty R, Elkashty OA, Hany E. Photobiostimulation conjugated with stem cells or their secretome for temporomandibular joint arthritis in a rat model. BMC Oral Health 2023; 23:720. [PMID: 37798702 PMCID: PMC10552280 DOI: 10.1186/s12903-023-03466-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 09/28/2023] [Indexed: 10/07/2023] Open
Abstract
BACKGROUND Temporomandibular joint (TMJ) arthritis is a debilitating, challenging condition and different methods have been implicated for its treatment. This study aimed to test the therapeutic potentials of low-level laser therapy (LLLT) associated with adipose derived stem cells (ADSC) or their derived secretome on a murine model induced arthritis. METHODS Forty eight rats were divided into four groups where group I was the sham control, the rest of animals were subjected to arthritis induction using complete Freund's adjuvant, then divided as follows: group II received phosphate buffered saline (PBS) intraarticular injection and irradiation of 0 j/cm2, group III received ADSCs derived secretome and irradiation of 38 j/cm2, and group IV received ADSCs and irradiation of 38 j/cm2 as well. One and three weeks after treatment, animals were euthanized, and paraffin blocks were processed for histological assessment by hematoxylin and eosin stain with histomorphometrical analysis. Histochemical evaluation of joint proteoglycan content was performed through toluidine blue stain, and immunohistochemical staining by the proinflammatory marker tumor necrosis factor-α (TNF-α) was performed followed by the relevant statistical tests. RESULTS The arthritis group showed histological signs of joint injury including cartilage atrophy, articular disc fibrosis, irregular osteochondral interface, and condylar bone resorption together with high inflammatory reaction and defective proteoglycan content. In contrast, the treated groups III and IV showed much restoration of the joint structure with normal cartilage and disc thickness. The inflammation process was significantly suppressed especially after three weeks as confirmed by the significant reduction in TNF-α positive immunostaining compared to the arthritic group, and the cartilage proteoglycan content also showed significant increase relative to the arthritic group. However, no significant difference between the results of the two treated groups was detected. CONCLUSION LLLT conjugated with ADSCs or ADSCs derived secretome can efficiently enhance the healing of arthritic TMJs. Stem cell secretome can be applied as a safe, potent therapy. However, further investigations are required to unravel its mechanism of action and pave its way as a safe, novel, cell free therapy.
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Affiliation(s)
- Rana El-Qashty
- Oral Biology Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Osama A Elkashty
- Oral Pathology Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Eman Hany
- Oral Biology Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
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Zhao Y, An Y, Zhou L, Wu F, Wu G, Wang J, Chen L. Animal Models of Temporomandibular Joint Osteoarthritis: Classification and Selection. Front Physiol 2022; 13:859517. [PMID: 35574432 PMCID: PMC9095932 DOI: 10.3389/fphys.2022.859517] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/04/2022] [Indexed: 01/11/2023] Open
Abstract
Temporomandibular joint osteoarthritis (TMJOA) is a common degenerative joint disease that can cause severe pain and dysfunction. It has a serious impact on the quality of lives of patients. Since mechanism underlying the pathogenesis of TMJOA is not fully understood, the development of effective tools for early diagnosis and disease-modifying therapies has been hindered. Animal models play a key role in understanding the pathological process of diseases and evaluating new therapeutic interventions. Although some similarities in disease processes between animals and humans are known, no one animal model is sufficient for studying all characteristics of TMJOA, as each model has different translatability to human clinical conditions. For the past 4 decades, TMJOA animal models have been studied by numerous researchers and can be broadly divided into induced, naturally occurring, and genetically modified models. The induced models can be divided into invasive models (intra-articular injection and surgical induction) or non-invasive models (mechanical loading, high-fat diet, and sleep deprivation). Different types of animal models simulate different pathological expressions of TMJOA and have their unique characteristics. Currently, mice, rats, and rabbits are commonly used in the study of TMJOA. This review sought to provide a general description of current experimental models of TMJOA and assist researchers in selecting the most appropriate models for different kinds of research.
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Affiliation(s)
- Yuqing Zhao
- Department of Orthodontics, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
- School of Stomatology, Heilongjiang Key Lab of Oral Biomedicine Materials and Clinical Application & Experimental Center for Stomatology Engineering, Jiamusi University, Jiamusi, China
| | - Yanxin An
- Department of General Surgery, The First Affiliated Hospital of Xi’an Medical University, Xi’an, China
| | - Libo Zhou
- School of Basic Medicine, Heilongjiang Key Lab of Oral Biomedicine Materials and Clinical Application & Experimental Center for Stomatology Engineering, Jiamusi University, Jiamusi, China
| | - Fan Wu
- School of Stomatology, Heilongjiang Key Lab of Oral Biomedicine Materials and Clinical Application & Experimental Center for Stomatology Engineering, Jiamusi University, Jiamusi, China
| | - Gaoyi Wu
- School of Stomatology, Heilongjiang Key Lab of Oral Biomedicine Materials and Clinical Application & Experimental Center for Stomatology Engineering, Jiamusi University, Jiamusi, China
| | - Jing Wang
- Department of Oral Implants, School of Stomatology, National Clinical Research Center for Oral Diseases & State Key Laboratory of Military Stomatology & Shaanxi Key Laboratory of Stomatology, The Fourth Military Medical University, Xi’an, China
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an, China
| | - Lei Chen
- Department of Orthodontics, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan, China
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Mao D, Wu M, Wei J, Zhou X, Yang L, Chen F. MicroRNA-101a-3p could be involved in the pathogenesis of temporomandibular joint osteoarthritis by mediating UBE2D1 and FZD4. J Oral Pathol Med 2020; 50:236-243. [PMID: 33187014 DOI: 10.1111/jop.13131] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 09/04/2020] [Accepted: 09/20/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disease that gradually affects the articular cartilage, synovium, and bone structure. To date, the molecular mechanism of TMJOA pathogenesis remains unclear. The aim of this study was to explore the biological function of the micro-ribonucleic acid 101a-3p (miR-101a-3p) and its role in TMJOA. METHODS We detected the effect of interleukin-1β (IL-1β) on chondrocyte proliferation using Cell Counting Kit-8 (CCK-8) technology. Using quantitative polymerase chain reaction (qPCR), we detected transcription levels of miR-101a-3p in a rat model with TMJOA and inflamed chondrocytes, as well as in a group of normal rats. The effect of miR-101a-3p on apoptosis was examined in vitro using flow cytometry (FCM). We then analyzed the target of miR-101a-3p via bioinformatics and confirmed it using a luciferase reporter assay (LRA). RESULTS We showed that IL-1β could inhibit proliferation of chondrocytes. We found that miR-101a-3p levels were significantly lower in the rat inflammation model with TMJOA and inflamed chondrocytes than in the normal group. Additionally, miR-101a-3p substantially promoted apoptosis of chondrocytes, and both bioinformatic analyses and LRA found that this miRNA targeted the genes ubiquitin-conjugating enzyme 2D1 (UBE2D1) and Frizzled class receptor 4 (FZD4). CONCLUSION Our results suggested that miR-101a-3p was involved in the pathogenesis of TMJOA and that its mechanism was probably interaction with its target genes UBE2D1 and FZD4.
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Affiliation(s)
- Dan Mao
- Department of Prosthetics, The Affiliated Stomatology Hospital of Zunyi Medical University, Zunyi Medical University, Zunyi, China
| | - Mingsong Wu
- Key Laboratory of Oral Disease Research in General Colleges and Universities of Guizhou Province, Zunyi Medical University, Zunyi, China
| | - Jiying Wei
- Department of Prosthetics, The Affiliated Stomatology Hospital of Zunyi Medical University, Zunyi Medical University, Zunyi, China
| | - Xiangwen Zhou
- Department of Prosthetics, The Affiliated Stomatology Hospital of Zunyi Medical University, Zunyi Medical University, Zunyi, China
| | - Lan Yang
- Department of Prosthetics, The Affiliated Stomatology Hospital of Zunyi Medical University, Zunyi Medical University, Zunyi, China
| | - Fang Chen
- Department of Prosthetics, The Affiliated Stomatology Hospital of Zunyi Medical University, Zunyi Medical University, Zunyi, China
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The Roles of Indian Hedgehog Signaling in TMJ Formation. Int J Mol Sci 2019; 20:ijms20246300. [PMID: 31847127 PMCID: PMC6941023 DOI: 10.3390/ijms20246300] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/10/2019] [Indexed: 01/15/2023] Open
Abstract
The temporomandibular joint (TMJ) is an intricate structure composed of the mandibular condyle, articular disc, and glenoid fossa in the temporal bone. Apical condylar cartilage is classified as a secondary cartilage, is fibrocartilaginous in nature, and is structurally distinct from growth plate and articular cartilage in long bones. Condylar cartilage is organized in distinct cellular layers that include a superficial layer that produces lubricants, a polymorphic/progenitor layer that contains stem/progenitor cells, and underlying layers of flattened and hypertrophic chondrocytes. Uniquely, progenitor cells reside near the articular surface, proliferate, undergo chondrogenesis, and mature into hypertrophic chondrocytes. During the past decades, there has been a growing interest in the molecular mechanisms by which the TMJ develops and acquires its unique structural and functional features. Indian hedgehog (Ihh), which regulates skeletal development including synovial joint formation, also plays pivotal roles in TMJ development and postnatal maintenance. This review provides a description of the many important recent advances in Hedgehog (Hh) signaling in TMJ biology. These include studies that used conventional approaches and those that analyzed the phenotype of tissue-specific mouse mutants lacking Ihh or associated molecules. The recent advances in understanding the molecular mechanism regulating TMJ development are impressive and these findings will have major implications for future translational medicine tools to repair and regenerate TMJ congenital anomalies and acquired diseases, such as degenerative damage in TMJ osteoarthritic conditions.
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Wang D, Yang H, Zhang M, Zhang H, Lu L, Zhang J, Wan X, Wang M. Insulin-like growth factor-1 engaged in the mandibular condylar cartilage degeneration induced by experimental unilateral anterior crossbite. Arch Oral Biol 2019; 98:17-25. [DOI: 10.1016/j.archoralbio.2018.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 11/01/2018] [Accepted: 11/01/2018] [Indexed: 02/06/2023]
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Manocha S, Farokhnia N, Khosropanah S, Bertol JW, Santiago J, Fakhouri WD. Systematic review of hormonal and genetic factors involved in the nonsyndromic disorders of the lower jaw. Dev Dyn 2019; 248:162-172. [PMID: 30576023 DOI: 10.1002/dvdy.8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 11/30/2018] [Accepted: 12/14/2018] [Indexed: 12/14/2022] Open
Abstract
Mandibular disorders are among the most common birth defects in humans, yet the etiological factors are largely unknown. Most of the neonates affected by mandibular abnormalities have a sequence of secondary anomalies, including airway obstruction and feeding problems, that reduce the quality of life. In the event of lacking corrective surgeries, patients with mandibular congenital disorders suffer from additional lifelong problems such as sleep apnea and temporomandibular disorders, among others. The goal of this systematic review is to gather evidence on hormonal and genetic factors that are involved in signaling pathways and interactions that are potentially associated with the nonsyndromic mandibular disorders. We found that members of FGF and BMP pathways, including FGF8/10, FGFR2/3, BMP2/4/7, BMPR1A, ACVR1, and ACVR2A/B, have a prominent number of gene-gene interactions among all identified genes in this review. Gene ontology of the 154 genes showed that the functional gene sets are involved in all aspects of cellular processes and organogenesis. Some of the genes identified by the genome-wide association studies of common mandibular disorders are involved in skeletal formation and growth retardation based on animal models, suggesting a potential direct role as genetic risk factors in the common complex jaw disorders. Developmental Dynamics 248:162-172, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Srishti Manocha
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Nadia Farokhnia
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Sepideh Khosropanah
- Ostrow School of Dentistry, University of Southern California, California, Los Angeles
| | - Jessica W Bertol
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Joel Santiago
- Pró-Reitoria de Pesquisa e Pós-graduação (PRPPG), Universidade do Sagrado Coração, Jardim Brasil, Bauru, Sao Paulo, Brazil
| | - Walid D Fakhouri
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas.,Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center, Houston, Texas
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Kurio N, Saunders C, Bechtold TE, Salhab I, Nah HD, Sinha S, Billings PC, Pacifici M, Koyama E. Roles of Ihh signaling in chondroprogenitor function in postnatal condylar cartilage. Matrix Biol 2018; 67:15-31. [PMID: 29447948 DOI: 10.1016/j.matbio.2018.02.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/09/2018] [Accepted: 02/10/2018] [Indexed: 12/14/2022]
Abstract
Condylar articular cartilage in mouse temporomandibular joint develops from progenitor cells near the articulating surface that proliferate, undergo chondrogenesis and mature into hypertrophic chondrocytes. However, it remains unclear how these processes are regulated, particularly postnatally. Here we focused on the apical polymorphic layer rich in progenitors and asked whether the phenotype and fate of the cells require signaling by Indian hedgehog (Ihh) previously studied in developing long bones. In condyles in newborn mice, the apical polymorphic/progenitor cell layer was ~10 cell layer-thick and expressed the articular matrix marker Tenascin-C (Tn-C), and the underlying thick cell layer expressed Tn-C as well as the chondrogenic master regulator Sox9. By 1 month, condylar cartilage had gained its full width, but became thinner along its main longitudinal axis and displayed hypertrophic chondrocytes. By 3 months, articular cartilage consisted of a 2-3 cell layer-thick zone of superficial cells and chondroprogenitors expressing both Tn-C and Sox9 and a bottom zone of chondrocytes displaying vertical matrix septa. EdU cell tracing in juvenile mice revealed that conversion of chondroprogenitors into chondrocytes and hypertrophic chondrocytes required about 48 and 72 h, respectively. Notably, EdU injection in 3 month-old mice labeled both progenitors and maturing chondrocytes by 96 h. Conditional ablation of Ihh in juvenile/early adult mice compromised chondroprogenitor organization and function and led to reduced chondroprogenitor and chondrocyte proliferation. The phenotype of mutant condyles worsened over time as indicated by apoptotic chondrocyte incidence, ectopic chondrocyte hypertrophy, chondrocyte column derangement and subchondral bone deterioration. In micromass cultures of condylar apical cells, hedgehog (Hh) treatment stimulated chondrogenesis and alkaline phosphatase (APase) activity, while treatment with HhAntag inhibited both. Our findings indicate that the chondroprogenitor layer is continuously engaged in condylar growth postnatally and its organization and functioning depend on hedgehog signaling.
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Affiliation(s)
- Naito Kurio
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Oral and Maxillofacial Surgery, Okayama University Graduate School, 2-5-1, Okayama, Japan
| | - Cheri Saunders
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Till E Bechtold
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Orofacial Orthopaedics, Center of Dentistry and Oral Medicine, University Hospital Tuebingen, D-72076 Tuebingen, Germany
| | - Imad Salhab
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Hyun-Duck Nah
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Sayantani Sinha
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Paul C Billings
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Maurizio Pacifici
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Eiki Koyama
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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Mesenchymal Stem Cells for Cartilage Regeneration of TMJ Osteoarthritis. Stem Cells Int 2017; 2017:5979741. [PMID: 29123550 PMCID: PMC5662817 DOI: 10.1155/2017/5979741] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 09/06/2017] [Indexed: 02/05/2023] Open
Abstract
Temporomandibular joint osteoarthritis (TMJ OA) is a degenerative disease, characterized by progressive cartilage degradation, subchondral bone remodeling, synovitis, and chronic pain. Due to the limited self-healing capacity in condylar cartilage, traditional clinical treatments have limited symptom-modifying and structure-modifying effects to restore impaired cartilage as well as other TMJ tissues. In recent years, stem cell-based therapy has raised much attention as an alternative approach towards tissue repair and regeneration. Mesenchymal stem cells (MSCs), derived from the bone marrow, synovium, and even umbilical cord, play a role as seed cells for the cartilage regeneration of TMJ OA. MSCs possess multilineage differentiation potential, including chondrogenic differentiation as well as osteogenic differentiation. In addition, the trophic modulations of MSCs exert anti-inflammatory and immunomodulatory effects under aberrant conditions. Furthermore, MSCs combined with appropriate scaffolds can form cartilaginous or even osseous compartments to repair damaged tissue and impaired function of TMJ. In this review, we will briefly discuss the pathogenesis of cartilage degeneration in TMJ OA and emphasize the potential sources of MSCs and novel approaches for the cartilage regeneration of TMJ OA, particularly focusing on the MSC-based therapy and tissue engineering.
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Boughner JC. Implications of Vertebrate Craniodental Evo-Devo for Human Oral Health. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2017; 328:321-333. [PMID: 28251806 DOI: 10.1002/jez.b.22734] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 12/21/2016] [Accepted: 01/30/2017] [Indexed: 12/12/2022]
Abstract
Highly processed diets eaten by postindustrial modern human populations coincide with higher frequencies of third molar impaction, malocclusion, and temporomandibular joint disorders that affect millions of people worldwide each year. Current treatments address symptoms, not causes, because the multifactorial etiologies of these three concerns mask which factors incline certain people to malocclusion, impaction, and/or joint issues. Deep scientific curiosity about the origins of jaws and dentitions continues to yield rich insights about the developmental genetic mechanisms that underpin healthy craniodental morphogenesis and integration. Mounting evidence from evolution and development (Evo-Devo) studies suggests that function is another mechanism important to healthy craniodental integration and fit. Starting as early as weaning, softer diets and thus lower bite forces appear to relax or disrupt integration of oral tissues, alter development and growth, and catalyze impaction, malocclusion, and jaw joint disorders. How developing oral tissues respond to bite forces remains poorly understood, but biomechanical feedback seems to alter balances of local bone resorption and deposition at the tooth-bone interface as well as affect tempos and amounts of facial outgrowth. Also, behavioral changes in jaw function and parafunction contribute to degeneration and pain in joint articular cartilages and masticatory muscles. The developmental genetic contribution to craniodental misfits and disorders is undeniable but still unclear; however, at present, human diet and jaw function remain important and much more actionable clinical targets. New Evo-Devo studies are needed to explain how function interfaces with craniodental phenotypic plasticity, variation, and evolvability to yield a spectrum of healthy and mismatched dentitions and jaws.
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Affiliation(s)
- Julia C Boughner
- Department of Anatomy and Cell Biology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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13
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Bechtold TE, Saunders C, Decker RS, Um HB, Cottingham N, Salhab I, Kurio N, Billings PC, Pacifici M, Nah HD, Koyama E. Osteophyte formation and matrix mineralization in a TMJ osteoarthritis mouse model are associated with ectopic hedgehog signaling. Matrix Biol 2016; 52-54:339-354. [PMID: 26945615 DOI: 10.1016/j.matbio.2016.03.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/01/2016] [Accepted: 03/01/2016] [Indexed: 12/28/2022]
Abstract
The temporomandibular joint (TMJ) is a diarthrodial joint that relies on lubricants for frictionless movement and long-term function. It remains unclear what temporal and causal relationships may exist between compromised lubrication and onset and progression of TMJ disease. Here we report that Proteoglycan 4 (Prg4)-null TMJs exhibit irreversible osteoarthritis-like changes over time and are linked to formation of ectopic mineralized tissues and osteophytes in articular disc, mandibular condyle and glenoid fossa. In the presumptive layer of mutant glenoid fossa's articulating surface, numerous chondrogenic cells and/or chondrocytes emerged ectopically within the type I collagen-expressing cell population, underwent endochondral bone formation accompanied by enhanced Ihh expression, became entrapped into temporal bone mineralized matrix, and thereby elicited excessive chondroid bone formation. As the osteophytes grew, the roof of the glenoid fossa/eminence became significantly thicker and flatter, resulting in loss of its characteristic concave shape for accommodation of condyle and disc. Concurrently, the condyles became flatter and larger and exhibited ectopic bone along their neck, likely supporting the enlarged condylar heads. Articular discs lost their concave configuration, and ectopic cartilage developed and articulated with osteophytes. In glenoid fossa cells in culture, hedgehog signaling stimulated chondrocyte maturation and mineralization including alkaline phosphatase, while treatment with hedgehog inhibitor HhAntag prevented such maturation process. In sum, our data indicate that Prg4 is needed for TMJ integrity and long-term postnatal function. In its absence, progenitor cells near presumptive articular layer and disc undergo ectopic chondrogenesis and generate ectopic cartilage, possibly driven by aberrant activation of Hh signaling. The data suggest also that the Prg4-null mice represent a useful model to study TMJ osteoarthritis-like degeneration and clarify its pathogenesis.
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Affiliation(s)
- Till E Bechtold
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Orthodontics and Orofacial Orthopaedics, Center of Dentistry, Oral Medicine and Maxillofacial Surgery, University Hospital Tuebingen, D-72076 Tuebingen, Germany
| | - Cheri Saunders
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Rebekah S Decker
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Hyo-Bin Um
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Naiga Cottingham
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Imad Salhab
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Naito Kurio
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Paul C Billings
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Maurizio Pacifici
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Hyun-Duck Nah
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Eiki Koyama
- Division of Orthopaedic Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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14
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Liang W, Li X, Gao B, Gan H, Lin X, Liao L, Li C. Observing the development of the temporomandibular joint in embryonic and post-natal mice using various staining methods. Exp Ther Med 2015; 11:481-489. [PMID: 26893634 PMCID: PMC4734204 DOI: 10.3892/etm.2015.2937] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 11/25/2015] [Indexed: 12/22/2022] Open
Abstract
The temporomandibular joint (TMJ) is a specialized synovial joint that is essential for the movement and function of the mammalian jaw. The TMJ develops from two mesenchymal condensations, and is composed of the glenoid fossa that originates from the otic capsule by intramembranous ossification, the mandibular condyle of the temporal bone and a fibrocartilagenous articular disc derived from a secondary cartilaginous joint by endochondral ossification. However, the development of the TMJ remains unclear. In the present study, the formation and development of the mouse TMJ was investigated between embryonic day 13.5 and post-natal day 180 in order to elucidate the morphological and molecular alterations that occur during this period. TMJ formation appeared to proceed in three stages: Initiation or blastema stage; growth and cavitation stage; and the maturation or completion stage. In order to investigate the activity of certain transcription factors on TMJ formation and development, the expression of extracellular matrix (ECM), sex determining region Y-box 9, runt-related transcription factor 2, Indian hedgehog homolog, Osterix, collagen I, collagen II, aggrecan, total matrix metalloproteinase (MMP), MMP-9 and MMP-13 were detected in the TMJ using in situ and/or immunohistochemistry. The results indicate that the transcription factors, ECM and MMP serve critical functions in the formation and development of the mouse TMJ. In summary, the development of the mouse TMJ was investigated, and the molecular regulation of mouse TMJ formation was partially characterized. The results of the present study may aid the systematic understanding of the physiological processes underlying TMJ formation and development in mice.
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Affiliation(s)
- Wenna Liang
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Xihai Li
- Academy of Integrative Medicine, Institute of Bone Diseases, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Bizhen Gao
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Huijuan Gan
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Xuejuan Lin
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Linghong Liao
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
| | - Candong Li
- College of Traditional Chinese Medicine, Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian 350122, P.R. China
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15
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Hinton RJ, Jing J, Feng JQ. Genetic Influences on Temporomandibular Joint Development and Growth. Curr Top Dev Biol 2015; 115:85-109. [PMID: 26589922 DOI: 10.1016/bs.ctdb.2015.07.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The temporomandibular joint (TMJ) is a small synovial joint at which the mandible articulates with the skull during movements involved in speaking and mastication. However, the secondary cartilage lining its joint surfaces is indicative of a very different developmental history than limb cartilages. This review summarizes our current knowledge of genes that regulate the formation of primary components of the TMJ, as well as genes that regulate postnatal growth of the TMJ. Although the TMJ is regulated by some of the same genes that are important in limb joints, others appear unique to the TMJ or have different actions. Runx2, Sox9, and members of the TGF-β/BMP family are critical drivers of chondrogenesis during condylar cartilage morphogenesis, and Indian hedgehog (Ihh) is important for formation of the articular disc and cavitation. Osterix (Osx) is a critical regulator of endochondral bone formation during postnatal TMJ growth.
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Affiliation(s)
- Robert J Hinton
- Department of Biomedical Sciences, Texas A&M Baylor College of Dentistry, Dallas, Texas, USA.
| | - Junjun Jing
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Sichuan, PR China
| | - Jian Q Feng
- Department of Biomedical Sciences, Texas A&M Baylor College of Dentistry, Dallas, Texas, USA
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16
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Suzuki A, Iwata J. Mouse genetic models for temporomandibular joint development and disorders. Oral Dis 2015; 22:33-8. [PMID: 26096083 DOI: 10.1111/odi.12353] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 06/04/2015] [Indexed: 01/22/2023]
Abstract
The temporomandibular joint (TMJ) is a synovial joint essential for hinge and sliding movements of the mammalian jaw. Temporomandibular joint disorders (TMD) are dysregulations of the muscles or the TMJ in structure, function, and physiology, and result in pain, limited mandibular mobility, and TMJ noise and clicking. Although approximately 40-70% adults in the USA have at least one sign of TMD, the etiology of TMD remains largely unknown. Here, we highlight recent advances in our understanding of TMD in mouse models.
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Affiliation(s)
- A Suzuki
- Department of Diagnostic & Biomedical Sciences, School of Dentistry, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA.,Center for Craniofacial Research, UTHealth, Houston, TX, USA
| | - J Iwata
- Department of Diagnostic & Biomedical Sciences, School of Dentistry, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA.,Center for Craniofacial Research, UTHealth, Houston, TX, USA
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17
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Sangani D, Suzuki A, VonVille H, Hixson JE, Iwata J. Gene Mutations Associated with Temporomandibular Joint Disorders: A Systematic Review. ACTA ACUST UNITED AC 2015; 2. [PMID: 27695703 PMCID: PMC5045035 DOI: 10.4236/oalib.1101583] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Background The temporomandibular joint (TMJ) is a bilateral synovial joint between the mandible and the temporal bone of the skull. TMJ disorders (TMDs) are a set of complicated and poorly understood clinical conditions, in which TMDs are associated with a number of symptoms including pain and limited jaw movement. The increasing scientific evidence suggests that genetic factors play a significant role in the pathology of TMDs. However, the underlying mechanism of TMDs remains largely unknown. Objective The study aimed to determine the associated genes to TMDs in humans and animals. Methods The literature search was conducted through databases including Medline (Ovid), EMBASE (Ovid), and PubMed (NLM) by using scientific terms for TMDs and genetics in March 2015. Additional studies were identified by searching bibliographies of highly relevant articles and Scopus (Elsevier). Results Our systematic analyses identified 31 articles through literature searches. A total of 112 genes were identified to be significantly and specifically associated with TMDs. Conclusion Our systematic review provides a list of accurate genes associated with TMDs and suggests a genetic contribution to the pathology of TMDs.
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Affiliation(s)
- Dhruvee Sangani
- Department of Epidemiology, Human Genetics & Environmental Sciences, The University of Texas School of Public Health, Houston, TX, USA; Department of Diagnostic & Biomedical Sciences, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX, USA
| | - Akiko Suzuki
- Department of Diagnostic & Biomedical Sciences, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX, USA; Center for Craniofacial Research, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX, USA
| | - Helena VonVille
- The University of Texas School of Public Health Library, Houston, TX, USA
| | - James E Hixson
- Department of Epidemiology, Human Genetics & Environmental Sciences, The University of Texas School of Public Health, Houston, TX, USA
| | - Junichi Iwata
- Department of Diagnostic & Biomedical Sciences, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX, USA; Center for Craniofacial Research, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX, USA; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA
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18
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Wang XD, Zhang JN, Gan YH, Zhou YH. Current understanding of pathogenesis and treatment of TMJ osteoarthritis. J Dent Res 2015; 94:666-73. [PMID: 25744069 DOI: 10.1177/0022034515574770] [Citation(s) in RCA: 276] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Osteoarthritis is a common disease that can cause severe pain and dysfunction in any joint, including the temporomandibular joint (TMJ). TMJ osteoarthritis (TMJOA) is an important subtype in the classification of temporomandibular disorders. TMJOA pathology is characterized by progressive cartilage degradation, subchondral bone remodeling, and chronic inflammation in the synovial tissue. However, the exact pathogenesis and process of TMJOA remain to be understood. An increasing number of studies have recently focused on inflammation and remodeling of subchondral bone during the early stage of TMJOA, which may elucidate the possible mechanism of initiation and progression of TMJOA. The treatment strategy for TMJOA aims at relieving pain, preventing the progression of cartilage and subchondral bone destruction, and restoring joint function. Conservative therapy with nonsteroidal anti-inflammatory drugs, splint, and physical therapy, such as low-energy laser and arthrocentesis, are the most common treatments for TMJOA. These therapies are effective in most cases in relieving the signs and symptoms, but their long-term therapeutic effect on the pathologic articular structure is unsatisfactory. A treatment that can reverse the damage of TMJOA remains unavailable to date. Treatments that prevent the progression of cartilage degradation and subchondral bone damage should be explored, and regeneration for the TMJ may provide the ideal long-term solution. This review summarizes the current understanding of mechanisms underlying the pathogenesis and treatment of TMJOA.
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Affiliation(s)
- X D Wang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China
| | - J N Zhang
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China
| | - Y H Gan
- Center for Temporomandibular Disorders and Orofacial Pain, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China Central Laboratory, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China
| | - Y H Zhou
- Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China Center for Craniofacial Stem Cell Research and Regeneration, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China
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Koyama E, Saunders C, Salhab I, Decker RS, Chen I, Um H, Pacifici M, Nah HD. Lubricin is Required for the Structural Integrity and Post-natal Maintenance of TMJ. J Dent Res 2014; 93:663-70. [PMID: 24834922 DOI: 10.1177/0022034514535807] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 04/24/2014] [Indexed: 01/12/2023] Open
Abstract
The Proteoglycan 4 (Prg4) product lubricin plays essential roles in boundary lubrication and movement in limb synovial joints, but its roles in temporomandibular joint (TMJ) are unclear. Thus, we characterized the TMJ phenotype in wild-type and Prg4(-/-) mouse littermates over age. As early as 2 weeks of age, mutant mice exhibited hyperplasia in the glenoid fossa articular cartilage, articular disc, and synovial membrane. By 1 month of age, there were fewer condylar superficial tenascin-C/Col1-positive cells and more numerous apoptotic condylar apical cells, while chondroprogenitors displayed higher mitotic activity, and Sox9-, Col2-, and ColX-expressing chondrocyte zones were significantly expanded. Mutant subchondral bone contained numerous Catepsin K-expressing osteoclasts at the chondro-osseous junction, increased invasive marrow cavities, and suboptimal subchondral bone. Mutant glenoid fossa, disc, synovial cells, and condyles displayed higher Hyaluronan synthase 2 expression. Mutant discs also lost their characteristic concave shape, exhibited ectopic chondrocyte differentiation, and occasionally adhered to condylar surfaces. A fibrinoid substance of unclear origin often covered the condylar surface. By 6 months of age, mutant condyles displayed osteoarthritic degradation with apical/mid-zone separation. In sum, lubricin exerts multiple essential direct and indirect roles to preserve TMJ structural and cellular integrity over post-natal life.
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Affiliation(s)
| | | | - I Salhab
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19107, USA
| | | | - I Chen
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19107, USA
| | - H Um
- Division of Orthopaedic Surgery
| | | | - H D Nah
- Division of Plastic and Reconstructive Surgery, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19107, USA
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