1
|
Guo H, Yang L, Liu J, Chen L, Huang Y, Li J. KLF5 promotes the ossification process of ligamentum flavum by transcriptionally activating CX43. J Orthop Surg Res 2024; 19:244. [PMID: 38622696 PMCID: PMC11020807 DOI: 10.1186/s13018-024-04702-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/25/2024] [Indexed: 04/17/2024] Open
Abstract
BACKGROUND Ossification of ligamentum flavum (OLF) is a prevalent degenerative spinal disease, typically causing severe neurological dysfunction. Kruppel-like factor 5 (KLF5) plays an essential role in the regulation of skeletal development. However, the mechanism KLF5 plays in OLF remains unclear, necessitating further investigative studies. METHODS qRT-PCR, immunofluorescent staining and western blot were used to measure the expression of KLF5. Alkaline Phosphatase (ALP) staining, Alizarin red staining (ARS), and the expression of Runt-related transcription factor 2 (RUNX2), osteopontin (OPN), and osteocalcin (OCN) were used to evaluate the osteogenic differentiation. Luciferase activity assay and ChIP-PCR were performed to investigate the molecular mechanisms. RESULTS KLF5 was significantly upregulated in OLF fibroblasts in contrast to normal ligamentum flavum (LF) fibroblasts. Silencing KLF5 diminished osteogenic markers and mineralized nodules, while its overexpression had the opposite effect, confirming KLF5's role in promoting ossification. Moreover, KLF5 promotes the ossification of LF by activating the transcription of Connexin 43 (CX43), and overexpressing CX43 could reverse the suppressive impact of KLF5 knockdown on OLF fibroblasts' osteogenesis. CONCLUSION KLF5 promotes the OLF by transcriptionally activating CX43. This finding contributes significantly to our understanding of OLF and may provide new therapeutic targets.
Collapse
Affiliation(s)
- Hubing Guo
- The First Department of Orthopaedic Surgery, The First Hospital of Tianshui, Tianshui, Gansu, 741000, China
| | - Lingxia Yang
- Department of Odermatology, The First Hospital of Tianshui, Tianshui, Gansu, 741000, China
| | - Jin Liu
- The First Department of Orthopaedic Surgery, The First Hospital of Tianshui, Tianshui, Gansu, 741000, China
| | - Liqi Chen
- The First Department of Orthopaedic Surgery, The First Hospital of Tianshui, Tianshui, Gansu, 741000, China
| | - Yufeng Huang
- The First Department of Orthopaedic Surgery, The First Hospital of Tianshui, Tianshui, Gansu, 741000, China
| | - Jinsong Li
- Department of Spine Surgery, The Third Xiangya Hospital, Central South University, No.138 Tongzipo Road, Changsha, 410013, Hunan, China.
| |
Collapse
|
2
|
Nishikawa M, Yoshimura M, Naito K, Yamagata T, Goto H, Hara M, Ikuno H, Goto T. The Symptomatic Calcification and Ossification of the Ligamentum Flavum in the Spine: Our Experience and Review of the Literature. J Clin Med 2023; 13:105. [PMID: 38202112 PMCID: PMC10780021 DOI: 10.3390/jcm13010105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/17/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024] Open
Abstract
INTRODUCTION We report our experience regarding the clinical features and pathological findings of the calcification of the ligamentum flavum (CLF) and ossification of the ligamentum flavum (OLF) in the spine. In addition, we reviewed the previous studies on CLF and OLF to enhance the understanding of these conditions. MATERIALS AND METHODS We compared the clinical, radiological, and histopathological features of CLF and OLF. RESULTS In CLF, a computed tomography (CT) scan showed egg-shaped or speck-like calcification in the ligamentum flavum. Magnetic resonance (MR) imaging demonstrated spinal cord compression due to a thickened ligamentum flavum, which appeared as a low-intensity mass. Pathological findings demonstrated fused islands of calcification resembling sand-like calcification. In OLF, CT showed beak-like ossification extending into the intervertebral foramen. MR imaging demonstrated spinal cord compression by a low-intensity mass. Pathological findings revealed laminar ossification of LF with chondrocytes near the calcification and laminar hyaline cartilage. CONCLUSIONS CLF and OLF appear to be distinct entities based on their clinical, neuroradiological, histopathological, and pathogenetic features. We suggest that the causes of CLF include both metabolic and dystrophic factors, while the pathogenesis of OLF is characterized by enchondral ossification induced by a genetic cascade triggered by shearing/tension stress.
Collapse
Affiliation(s)
- Misao Nishikawa
- Department of Neurosurgery, Moriguchi-Ikuno Memorial Hospital, 6-17-33 Satanakamachi, Moriguchi City 570-0002, Osaka, Japan; (T.Y.); (M.H.)
- Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka City 545-8595, Osaka, Japan; (K.N.); (T.G.)
| | - Masaki Yoshimura
- Department of Neuropathology, Yao Tokusyukai General Hospital, 1-17, Wakakusacho, Yao City 581-0011, Osaka, Japan;
| | - Kentaro Naito
- Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka City 545-8595, Osaka, Japan; (K.N.); (T.G.)
| | - Toru Yamagata
- Department of Neurosurgery, Moriguchi-Ikuno Memorial Hospital, 6-17-33 Satanakamachi, Moriguchi City 570-0002, Osaka, Japan; (T.Y.); (M.H.)
| | - Hiroyuki Goto
- Department of Neurosurgery, Osaka Saiseikai Nakatsu Hospital, 2-10-39, Kita-ku, Osaka City 530-0012, Osaka, Japan;
| | - Mitsuhiro Hara
- Department of Neurosurgery, Moriguchi-Ikuno Memorial Hospital, 6-17-33 Satanakamachi, Moriguchi City 570-0002, Osaka, Japan; (T.Y.); (M.H.)
- Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka City 545-8595, Osaka, Japan; (K.N.); (T.G.)
| | - Hiromichi Ikuno
- Department of Radiology, Moriguchi-Ikuno Memorial Hospital, 6-17-33 Satanakamachi, Moriguchi City 570-0002, Osaka, Japan;
| | - Takeo Goto
- Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahimachi, Abeno-ku, Osaka City 545-8595, Osaka, Japan; (K.N.); (T.G.)
| |
Collapse
|
3
|
Tuo Y, Hu L, Gu W, Yuan X, Wu J, Ma D, Luo D, Zhang X, Li X, Yang S, Yuan H. Identification of Bone Morphometric Protein-Related Hub Genes and Construction of a Transcriptional Regulatory Network in Patients With Ossification of the Ligamentum Flavum. Spine (Phila Pa 1976) 2023; 48:E317-E328. [PMID: 37384872 PMCID: PMC10445621 DOI: 10.1097/brs.0000000000004763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/06/2023] [Indexed: 07/01/2023]
Abstract
STUDY DESIGN Basic science laboratory study. OBJECTIVE To identify hub genes related to bone morphogenetic proteins (BMPs) in the ossification of the ligamentum flavum (OLF) and analyze their functional characteristics. SUMMARY OF BACKGROUND DATA The exact etiology and pathologic mechanism of OLF remain unclear. BMPs are pleiotropic osteoinductive proteins that may play a critical role in this condition. MATERIALS AND METHODS The GSE106253 and GSE106256 data sets were downloaded from the Gene Expression Omnibus database. The messenger RNA (mRNA) and long noncoding RNA expression profiles were obtained from GSE106253. The microRNA expression profiles were obtained from GSE106256. Differentially expressed genes were identified between OLF and non-OLF groups and then intersected with BMP-related genes to obtain differentially expressed BMP-related genes. The least absolute shrinkage selection operator and support vector machine recursive feature elimination were used to screen hub genes. Furthermore, a competing endogenous RNA network was constructed to explain the expression regulation of the hub genes in OLF. Finally, the protein and mRNA expression levels of the hub genes were verified using Western blot and real-time polymerase chain reaction, respectively. RESULTS We identified 671 Differentially expressed genes and 32 differentially expressed BMP-related genes. Hub genes ADIPOQ , SCD , SCX , RPS18 , WDR82 , and SPON1 , identified through the least absolute shrinkage selection operator and support vector machine recursive feature elimination analyses, showed high diagnostic values for OLF. Furthermore, the competing endogenous RNA network revealed the regulatory mechanisms of the hub genes. Real-time polymerase chain reaction showed that the mRNA expression of the hub genes was significantly downregulated in the OLF group compared with the non-OLF group. Western blot showed that the protein levels of ADIPOQ, SCD, WDR82 , and SPON1 were significantly downregulated, whereas those of SCX and RPS18 were significantly upregulated in the OLF group compared with the non-OLF group. CONCLUSION This study is the first to identify BMP-related genes in OLF pathogenesis through bioinformatics analysis. ADIPOQ , SCD , SCX , RPS18 , WDR82 , and SPON1 were identified as hub genes for OLF. The identified genes may serve as potential therapeutic targets for treating patients with OLF.
Collapse
Affiliation(s)
- Yifan Tuo
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Lihong Hu
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| | - Wenbo Gu
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Xiaoya Yuan
- St. Anne’s—Belfield School, Charlottesville, VA
| | - Jide Wu
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Da Ma
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Di Luo
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Xiao Zhang
- Clinical College of Ningxia Medical University, Ningxia, China
| | - Xusheng Li
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| | - Shengsen Yang
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| | - Haifeng Yuan
- Department of Spine Surgery, General Hospital of Ningxia Medical University, Ningxia, China
| |
Collapse
|
4
|
Review of Basic Research about Ossification of the Spinal Ligaments Focusing on Animal Models. J Clin Med 2023; 12:jcm12051958. [PMID: 36902744 PMCID: PMC10003841 DOI: 10.3390/jcm12051958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/25/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Ossification of the posterior longitudinal ligament (OPLL) is a heterotopic ossification that may cause spinal cord compression. With the recent development of computed tomography (CT) imaging, it is known that patients with OPLL often have complications related to ossification of other spinal ligaments, and OPLL is now considered part of ossification of the spinal ligaments (OSL). OSL is known to be a multifactorial disease with associated genetic and environmental factors, but its pathophysiology has not been clearly elucidated. To elucidate the pathophysiology of OSL and develop novel therapeutic strategies, clinically relevant and validated animal models are needed. In this review, we focus on animal models that have been reported to date and discuss their pathophysiology and clinical relevance. The purpose of this review is to summarize the usefulness and problems of existing animal models and to help further the development of basic research on OSL.
Collapse
|
5
|
Hwang SH, Chung CK, Kim CH, Yang SH, Choi Y, Yoon J. Value of Additional Instrumented Fusion in the Treatment of Thoracic Ossification of the Ligamentum Flavum. J Korean Neurosurg Soc 2022; 65:719-729. [PMID: 35988925 PMCID: PMC9452387 DOI: 10.3340/jkns.2021.0167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 12/29/2021] [Indexed: 12/03/2022] Open
Abstract
Objective The ossification of the ligamentum flavum (OLF) is one of the major causes of thoracic myelopathy. Surgical decompression with or without instrumented fusion is the mainstay of treatment. However, few studies have reported on the added effect of instrumented fusion. The objective of this study was to compare clinical and radiological outcomes between surgical decompression without instrumented fusion (D-group) and that with instrumented fusion (F-group).
Methods A retrospective review was performed on 28 patients (D-group, n=17; F-group, n=11) with thoracic myelopathy due to OLF. The clinical parameters compared included scores of the Japanese Orthopedic Association (JOA), the Visual analogue scale of the back and leg (VAS-B and VAS-L), and the Korean version of the Oswestry disability index (K-ODI). Radiological parameters included the sagittal vertical axis (SVA), the pelvic tilt (PT), the sacral slope (SS), the thoracic kyphosis angle (TKA), the segmental kyphosis angle (SKA) at the operated level, and the lumbar lordosis angle (LLA; a negative value implying lordosis). These parameters were measured preoperatively, 1 year postoperatively, and 2 years postoperatively, and were compared with a linear mixed model.
Results After surgery, all clinical parameters were significantly improved in both groups, while VAS-L was more improved in the F-group than in the D-group (-3.4±2.5 vs. -1.3±2.2, p=0.008). Radiological outcomes were significantly different in terms of changes in TKA, SKA, and LLA. Changes in TKA, SKA, and LLA were 2.3°±4.7°, -0.1°±1.4°, and -1.3°±5.6° in the F-group, which were significantly lower than 6.8°±6.1°, 3.0°±2.8°, and 2.2°±5.3° in the D-group, respectively (p=0.013, p<0.0001, and p=0.037). Symptomatic recurrence of OLF occurred in one patient of the D-group at postoperative 24 months.
Conclusion Clinical improvement was achieved after decompression surgery for OLF regardless of whether instrumented fusion was added. However, adding instrumented fusion resulted in better outcomes in terms of lessening the progression of local and regional kyphosis and improving leg pain. Decompression with instrumented fusion may be a better surgical option for thoracic OLF.
Collapse
|
6
|
Connexin 43 affects thoracic ossification of ligamentum flavum by regulating the p38 MAPK-RUNX2 signaling pathway. Tissue Cell 2022; 76:101760. [PMID: 35220127 DOI: 10.1016/j.tice.2022.101760] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/24/2022] [Accepted: 02/18/2022] [Indexed: 01/14/2023]
Abstract
This study aimed to investigate the role of connexin 43 (CX43) in thoracic ossification of ligamentum flavum (TOLF) based on the p38 mitogen-activated protein kinase (p38MAPK)-runt-related transcription factor 2 (RUNX2) pathway. Immunohistochemistry was used to detect CX43 expression in TOLF and non-TOLF patients, fibroblasts of TOLF were isolated and induced osteogenic differentiation, and CX43 expression was detected by western blot analysis (WB). In addition, si-CX43 was used to intervene CX43, and SB203580 was used to inhibit the p38MAPK. The expressions of bone differentiation marker protein were detected by WB, and the ossification ability was analyzed by alizarin red staining. The interaction between RUNX2 and CX43 was identified by dual-luciferase reporter assay. Results found that CX43 was highly expressed during TOLF, and si-CX43 could inhibit the expression of alkaline phosphatase (ALP) and osteopontin (OPN), as well as inhibit TOLF and the p38MAPK-RUNX2 pathway. In addition, SB203580 showed a synergistic effect with si-CX43 to further inhibit TOLF and the expression of RUNX2. The dual-luciferase reporter assay confirmed that RUNX2 could bind to the CX43 promoter. In conclusion, CX43 promotes TOLF, which may be mediated by p38MAPK-RUNX2, and RUNX2 binds to the CX43 promoter to form a positive feedback regulatory loop during TOLF.
Collapse
|
7
|
Zhang B, Chen G, Chen X, Yang X, Fan T, Sun C, Chen Z. Integrating Bioinformatic Strategies with Real-World Data to Infer Distinctive Immunocyte Infiltration Landscape and Immunologically Relevant Transcriptome Fingerprints in Ossification of Ligamentum Flavum. J Inflamm Res 2021; 14:3665-3685. [PMID: 34354364 PMCID: PMC8331123 DOI: 10.2147/jir.s318009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 07/08/2021] [Indexed: 12/31/2022] Open
Abstract
Purpose Ossification of the ligamentum flavum (OLF) is a multifactorial disease characterized by an insidious and debilitating process of abnormal bone formation in ligamentum tissues. However, its definite pathogenesis has not been fully elucidated. Potential links between the immune system and various forms of heterotopic ossification have been discussed for many years, whereas no research investigated the immune effects on the initiation and development of OLF. Therefore, we attempt to shed light on this issue. Methods A series of bioinformatic algorithms were integrated to evaluate the immune score and the immunocyte infiltration patterns between OLF and normal samples, screen OLF-related and immune-related differentially expressed genes (OIDEGs), and analyze their biological functions. Correlation analysis inferred OIDEGs-related differentially expressed lncRNAs (OIDELs) and infiltrating immune cells (OIICs) to construct an immunoregulatory network. Results Differential immune score and immune cell infiltration were determined between two groups, and 10 OIDEGs with diverse biological function annotations were identified and verified. A lncRNA-gene-immunocyte regulatory network further revealed 10 OIDEGs, 41 OIDELs and 7 OIICs that were highly correlated. Among them, CD1E and STAT3 were predicted as hub genes whether at the expression level or interaction level. cDCs emerged as having the most prominent differences and the highest degree of connectivity. FO393414.3, AC096734.1, LINC01137 and DLX6-AS1 with the greatest number of OIDEGs were thought to be more likely to participate in immunoregulation of OLF. Conclusion This is the first research to preliminarily elucidate OLF-related immunocyte infiltration landscape and immune-associated transcriptome signatures based on bioinformatic strategies and real-world data, which may provide compelling insights into the pathogenesis and therapeutic targets of OLF.
Collapse
Affiliation(s)
- Baoliang Zhang
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Guanghui Chen
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Xi Chen
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Xiaoxi Yang
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Tianqi Fan
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Chuiguo Sun
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| | - Zhongqiang Chen
- Peking University Third Hospital, Department of Orthopaedics, Beijing, 100191, People's Republic of China.,Engineering Research Center of Bone and Joint Precision Medicine, Beijing, 100191, People's Republic of China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, 100191, People's Republic of China
| |
Collapse
|
8
|
Gao R, Shi C, Yang C, Zhao Y, Chen X, Zhou X. Cyclic stretch promotes the ossification of ligamentum flavum by modulating the Indian hedgehog signaling pathway. Mol Med Rep 2020; 22:1119-1128. [PMID: 32626952 PMCID: PMC7339599 DOI: 10.3892/mmr.2020.11200] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 01/29/2020] [Indexed: 11/06/2022] Open
Abstract
The Indian hedgehog (IHH) signaling pathway is an important pathway for bone growth and development. The aim of the present study was to examine the role of the IHH signaling pathway in the development of the ossification of ligamentum flavum (OLF) at the cellular and tissue levels. The expression levels and localization of the osteogenic genes Runt-related transcription factor 2 (RUNX2), Osterix, alkaline phosphatase (ALP), osteocalcin (OCN) and IHH were evaluated in OLF tissues by reverse transcription-quantitative PCR (RT-qPCR) and immunohistochemistry. Non-ossified ligamentum flavum (LF) sections were used as control samples. The tissue explant method was used to obtain cultured LF cells. In addition, OLF cells were subjected to cyclic stretch application for 0, 6, 12 or 24 h. The expression levels of osteogenic genes, and the IHH signaling pathway genes IHH, Smoothened (SMO), GLI family zinc finger 1 (GLI1), GLI2 and GLI3 were evaluated with RT-qPCR and western blotting. Osteogenic differentiation was further evaluated by assessing ALP activity and staining. Moreover, the effect of cyclopamine (Cpn), an IHH signaling inhibitor, on osteogenic differentiation was examined. The RT-qPCR and immunohistochemical results indicated that the mRNA and protein expression levels of RUNX2, Osterix, ALP, OCN and IHH were significantly higher in the OLF group compared with the LF group. Furthermore, application of cyclic stretch to OLF cells resulted in greater ALP activity, and significant increases in mRNA and protein expression levels of RUNX2, Osterix, ALP and OCN in a time-d00ependent manner. Cyclic stretch application also led to significant increases in IHH signaling pathway genes, including IHH, SMO, GLI1 and GLI2, while no significant effect was found on GLI3 expression level. In addition, it was found that Cpn significantly reversed the effect of cyclic stretch on the ALP activity, and the expression levels of RUNX2, Osterix, ALP, OCN, GLI1 and GLI2. Collectively, the present results suggested that the IHH signaling pathway may mediate the effect of cyclic stretch on the OLF cells.
Collapse
Affiliation(s)
- Rui Gao
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P.R. China
| | - Changgui Shi
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P.R. China
| | - Chengwei Yang
- Department of Orthopedics, Lanzhou General Hospital of PLA, Lanzhou, Gansu 730050, P.R. China
| | - Yin Zhao
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P.R. China
| | - Xiongsheng Chen
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P.R. China
| | - Xuhui Zhou
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, P.R. China
| |
Collapse
|
9
|
Ramos-Mucci L, Javaheri B, van 't Hof R, Bou-Gharios G, Pitsillides AA, Comerford E, Poulet B. Meniscal and ligament modifications in spontaneous and post-traumatic mouse models of osteoarthritis. Arthritis Res Ther 2020; 22:171. [PMID: 32678020 PMCID: PMC7364489 DOI: 10.1186/s13075-020-02261-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 07/06/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Osteoarthritis (OA) is a whole joint disease that affects all joint tissues, with changes in the articular cartilage (AC), subchondral bone and synovium. Pathologies in menisci and ligaments, however, are rarely analysed, although both are known to play vital roles in the mechanical stability of the joint. The aim of our study was to describe the pathological changes in menisci and ligament during disease development in murine spontaneous and post-traumatic surgically induced OA and to quantify tissue mineralisation in the joint space using micro-computed tomography (μCT) imaging during OA progression. METHODS Knees of Str/ort mice (spontaneous OA model; 26-40 weeks) and C57CBA F1 mice following destabilisation of medial meniscus (DMM) surgery (post-traumatic OA model; 8 weeks after DMM), were used to assess histological meniscal and ligament pathologies. Joint space mineralised tissue volume was quantified by μCT. RESULTS Meniscal pathological changes in Str/ort mouse knees were associated with articular cartilage lesion severity. These meniscal changes included ossification, hyperplasia, cell hypertrophy, collagen type II deposition and Sox9 expression in the fibrous region near the attachment to the knee joint capsule. Anterior cruciate ligaments exhibited extracellular matrix changes and chondrogenesis particularly at the tibial attachment site, and ossification was seen in collateral ligaments. Similar changes were confirmed in the post-traumatic DMM model. μCT analysis showed increased joint space mineralised tissue volume with OA progression in both the post-traumatic and spontaneous OA models. CONCLUSIONS Modifications in meniscal and ligament mineralisation and chondrogenesis are seen with overt AC degeneration in murine OA. Although the aetiology and the consequences of such changes remain unknown, they will influence stability and load transmission of the joint and may therefore contribute to OA progression. In addition, these changes may have important roles in movement restriction and pain, which represent major human clinical symptoms of OA. Description of such soft tissue changes, in addition to AC degradation, should be an important aspect of future studies in mouse models in order to furnish a more complete understanding of OA pathogenesis.
Collapse
Affiliation(s)
- Lorenzo Ramos-Mucci
- Institute of Lifecourse and Medical Sciences, University of Liverpool, 6 West Derby street, L7 8TX, Liverpool, UK
| | - Behzad Javaheri
- Comparative Biomedical Sciences, The Royal Veterinary College, Royal College Street, London, NW1 0TU, UK
| | - Rob van 't Hof
- Institute of Lifecourse and Medical Sciences, University of Liverpool, 6 West Derby street, L7 8TX, Liverpool, UK
| | - George Bou-Gharios
- Institute of Lifecourse and Medical Sciences, University of Liverpool, 6 West Derby street, L7 8TX, Liverpool, UK
| | - Andrew A Pitsillides
- Comparative Biomedical Sciences, The Royal Veterinary College, Royal College Street, London, NW1 0TU, UK
| | - Eithne Comerford
- Institute of Lifecourse and Medical Sciences, University of Liverpool, 6 West Derby street, L7 8TX, Liverpool, UK
- Institute of Veterinary Science, Leahurst Campus, University of Liverpool, Chester High Rd, Neston, CH64 7TE, UK
| | - Blandine Poulet
- Institute of Lifecourse and Medical Sciences, University of Liverpool, 6 West Derby street, L7 8TX, Liverpool, UK.
| |
Collapse
|
10
|
Jezek J, Sepitka J, Daniel M, Kujal P, Blankova A, Waldauf P, Krbec M, Dousa P, Skala-Rosenbaum J, Samal F, Jirasek T. The role of vascularization on changes in ligamentum flavum mechanical properties and development of hypertrophy in patients with lumbar spinal stenosis. Spine J 2020; 20:1125-1133. [PMID: 32179155 DOI: 10.1016/j.spinee.2020.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND CONTEXT Ligamentum flavum (LF) induced lumbar spinal stenosis (LSS) is conditioned not only by its "gathering" but especially by hypertrophy. Previous studies have examined the pathophysiology and biochemical changes that cause the hypertrophy. Some studies have described a link between chronic LF inflammation and neovascularization but others have reported highly hypovascular LF tissue in LSS patients. Currently, there is no practical application for our knowledge of the pathophysiology of the LF hypertrophy. Considerations for future treatment include influencing this hypertrophy at the level of tissue mediators, which may slow the development of LSS. To our knowledge, there is no study of micromechanical properties of native LF to date. PURPOSE (1) To clarify the changes in vascularization, chondroid metaplasia, and the presence of inflammatory cell infiltration in LF associated with LSS. (2) To quantify changes in the micromechanical properties associated with LF degenerative processes. STUDY DESIGN/SETTING Vascular density analysis of degenerated and healthy human LF combined with measurement of micromechanical properties. METHODS The study involved 35 patients who underwent surgery between November 1, 2015 and October 1, 2016. The LSS group consisted of 20 patients and the control group consisted of 15 patients. LF samples were obtained during the operation and were used for histopathological and nanoindentation examinations. Sample vascularization was examined as microvascular density (Lv), which was morphometrically evaluated using semiautomatic detection in conjunction with NIS-Elements AR image analysis software. Samples were also histologically examined for the presence of chondroid metaplasia and inflammation. Mechanical properties of native LF samples were analyzed using the Hysitron TI 950 TriboIndenter nanomechanical testing system. RESULTS Vascular density was significantly lower in the LSS group. However, after excluding the effect of age, the difference was not significant. There was high association between Lv and age. With each increasing year of age, Lv decreased by 11.5 mm2. Vascular density decreased up to the age of 50. Over the age of 50, changes were no longer significant and Lv appeared to stabilize. No correlation was observed between Lv and the presence of inflammation or metaplasia; however, LSS patients had a significantly increased incidence of chondroid metaplasia and inflammatory signs. The mechanical properties of control group samples showed significantly higher stiffness than those samples obtained from the LSS group. CONCLUSION This study showed that Lv changes were not dependent on LSS but were age-dependent. Vascular density was found to decrease up to the age of 50. A significantly higher incidence of chondroid metaplasia and inflammation was observed in LSS patients. The mechanical property values measured by nanoindentation showed high microstructural heterogeneity of the tested ligaments. Our results showed that healthy ligaments were significantly stiffer than LSS ligaments. CLINICAL SIGNIFICANCE Prevention of the loss of LF vascularization during aging may influence stiffness of LF which in turn may slow down the LF degenerative processes and delay onset of LSS.
Collapse
Affiliation(s)
- Jakub Jezek
- Department of Orthopedics and Traumatology, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Srobarova 50, Praha 10, 100 34 Prague, Czech Republic.
| | - Josef Sepitka
- Division of Biomechanics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Czech Republic
| | - Matej Daniel
- Division of Biomechanics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Czech Republic
| | - Petr Kujal
- Department of Pathology, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic
| | - Alzbeta Blankova
- Department of Forensic Medicine, Regional Hospital Liberec, Czech Republic
| | - Petr Waldauf
- Department of Anesthesiology and Intensive Care Medicine, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic
| | - Martin Krbec
- Department of Orthopedics and Traumatology, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Srobarova 50, Praha 10, 100 34 Prague, Czech Republic
| | - Pavel Dousa
- Department of Orthopedics and Traumatology, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Srobarova 50, Praha 10, 100 34 Prague, Czech Republic
| | - Jiri Skala-Rosenbaum
- Department of Orthopedics and Traumatology, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Srobarova 50, Praha 10, 100 34 Prague, Czech Republic
| | - Filip Samal
- Department of Neurosurgery, Third Medical Faculty of Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic
| | - Tomas Jirasek
- Centrum Patos, Regional Hospital Liberec, Czech Republic
| |
Collapse
|
11
|
Pulik Ł, Mierzejewski B, Ciemerych MA, Brzóska E, Łęgosz P. The Survey of Cells Responsible for Heterotopic Ossification Development in Skeletal Muscles-Human and Mouse Models. Cells 2020; 9:cells9061324. [PMID: 32466405 PMCID: PMC7349686 DOI: 10.3390/cells9061324] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/16/2020] [Accepted: 05/21/2020] [Indexed: 12/18/2022] Open
Abstract
Heterotopic ossification (HO) manifests as bone development in the skeletal muscles and surrounding soft tissues. It can be caused by injury, surgery, or may have a genetic background. In each case, its development might differ, and depending on the age, sex, and patient's conditions, it could lead to a more or a less severe outcome. In the case of the injury or surgery provoked ossification development, it could be, to some extent, prevented by treatments. As far as genetic disorders are concerned, such prevention approaches are highly limited. Many lines of evidence point to the inflammatory process and abnormalities in the bone morphogenetic factor signaling pathway as the molecular and cellular backgrounds for HO development. However, the clear targets allowing the design of treatments preventing or lowering HO have not been identified yet. In this review, we summarize current knowledge on HO types, its symptoms, and possible ways of prevention and treatment. We also describe the molecules and cells in which abnormal function could lead to HO development. We emphasize the studies involving animal models of HO as being of great importance for understanding and future designing of the tools to counteract this pathology.
Collapse
Affiliation(s)
- Łukasz Pulik
- Department of Orthopaedics and Traumatology, Medical University of Warsaw, Lindley 4 St, 02-005 Warsaw, Poland;
| | - Bartosz Mierzejewski
- Department of Cytology, Faculty of Biology, University of Warsaw, Miecznikowa 1 St, 02-096 Warsaw, Poland; (B.M.); (M.A.C.)
| | - Maria A. Ciemerych
- Department of Cytology, Faculty of Biology, University of Warsaw, Miecznikowa 1 St, 02-096 Warsaw, Poland; (B.M.); (M.A.C.)
| | - Edyta Brzóska
- Department of Cytology, Faculty of Biology, University of Warsaw, Miecznikowa 1 St, 02-096 Warsaw, Poland; (B.M.); (M.A.C.)
- Correspondence: (E.B.); (P.Ł.); Tel.: +48-22-5542-203 (E.B.); +48-22-5021-514 (P.Ł.)
| | - Paweł Łęgosz
- Department of Orthopaedics and Traumatology, Medical University of Warsaw, Lindley 4 St, 02-005 Warsaw, Poland;
- Correspondence: (E.B.); (P.Ł.); Tel.: +48-22-5542-203 (E.B.); +48-22-5021-514 (P.Ł.)
| |
Collapse
|
12
|
Kim JM, Yang YS, Park KH, Ge X, Xu R, Li N, Song M, Chun H, Bok S, Charles JF, Filhol-Cochet O, Boldyreff B, Dinter T, Yu PB, Kon N, Gu W, Takarada T, Greenblatt MB, Shim JH. A RUNX2 stabilization pathway mediates physiologic and pathologic bone formation. Nat Commun 2020; 11:2289. [PMID: 32385263 PMCID: PMC7210266 DOI: 10.1038/s41467-020-16038-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 04/10/2020] [Indexed: 12/21/2022] Open
Abstract
The osteoblast differentiation capacity of skeletal stem cells (SSCs) must be tightly regulated, as inadequate bone formation results in low bone mass and skeletal fragility, and over-exuberant osteogenesis results in heterotopic ossification (HO) of soft tissues. RUNX2 is essential for tuning this balance, but the mechanisms of posttranslational control of RUNX2 remain to be fully elucidated. Here, we identify that a CK2/HAUSP pathway is a key regulator of RUNX2 stability, as Casein kinase 2 (CK2) phosphorylates RUNX2, recruiting the deubiquitinase herpesvirus-associated ubiquitin-specific protease (HAUSP), which stabilizes RUNX2 by diverting it away from ubiquitin-dependent proteasomal degradation. This pathway is important for both the commitment of SSCs to osteoprogenitors and their subsequent maturation. This CK2/HAUSP/RUNX2 pathway is also necessary for HO, as its inhibition blocked HO in multiple models. Collectively, active deubiquitination of RUNX2 is required for bone formation and this CK2/HAUSP deubiquitination pathway offers therapeutic opportunities for disorders of inappropriate mineralization.
Collapse
Affiliation(s)
- Jung-Min Kim
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Yeon-Suk Yang
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Kwang Hwan Park
- Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Xianpeng Ge
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ren Xu
- State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian, China
| | - Na Li
- State Key Laboratory of Cellular Stress Biology, Xiamen University, Fujian, China
| | - Minkyung Song
- Department of integrative biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Hyunho Chun
- Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Seoyeon Bok
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA
| | - Julia F Charles
- Department of Orthopedics and Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Odile Filhol-Cochet
- INSERM U1036, pour le Vivant/Biologie du Cancer et de l'Infection, Commissariat à l'Énergie Atomique et aux Énerigies Alternatives Grenoble, Grenoble, France
| | | | - Teresa Dinter
- Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Paul B Yu
- Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ning Kon
- Institute of Cancer Genetics, College of Physicians and Surgeons of Columbia University, New York, NY, USA
| | - Wei Gu
- Institute of Cancer Genetics, College of Physicians and Surgeons of Columbia University, New York, NY, USA
- Department of Pathology and Cell Biology, College of Physicians and Surgeons of Columbia University, New York, NY, USA
| | - Takeshi Takarada
- Department of Regenerative Science, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Matthew B Greenblatt
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA.
| | - Jae-Hyuck Shim
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
- Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, MA, USA.
| |
Collapse
|
13
|
Sugita D, Nakajima H, Kokubo Y, Takeura N, Yayama T, Matsumine A. Cyclic tensile strain facilitates ossification of the cervical posterior longitudinal ligament via increased Indian hedgehog signaling. Sci Rep 2020; 10:7231. [PMID: 32350355 PMCID: PMC7190672 DOI: 10.1038/s41598-020-64304-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 04/15/2020] [Indexed: 11/29/2022] Open
Abstract
The pathomechanisms of initiation and progression of ossification of the posterior longitudinal ligament (OPLL) are unclear. Indian hedgehog (Ihh) and related signaling molecules are key factors in normal enchondral ossification. The purpose of this study is to investigate the contribution of mechanical strain to OPLL and the relationship of Ihh with OPLL. Sections of the posterior longitudinal ligament (PLL) were obtained from 49 patients with OPLL and from 7 patients without OPLL. Cultured PLL cells were subjected to 24 hours of cyclic tensile strain. To identify differentially expressed genes associated with cyclic tensile strain, microarray analysis was performed. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified upregulation of various genes, particularly of the Hedgehog signaling pathway; Ihh and related genes had increased expression compared with controls after 24-hour cyclic tensile strain. In immunoblotting analysis, Ihh, Runx2, Sox9, Gli2, Gli3, and smoothened (SMO) had significantly increased expression after 6- or 12-hour cyclic tensile strain. OPLL samples were strongly immunopositive for Ihh, Sox9, Runx2, Gli2, Gli3, and SMO in the ossification front of OPLL. These results suggest that cyclic tensile strain induces abnormal activation of Ihh and related signaling molecules, and this might be important in the ossification process in OPLL.
Collapse
Affiliation(s)
- Daisuke Sugita
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Hideaki Nakajima
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan.
| | - Yasuo Kokubo
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Naoto Takeura
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Takafumi Yayama
- Department of Orthopaedic Surgery, Shiga University of Medical Science, Setatsukiwachou, Otsu, Shiga, 520-2192, Japan
| | - Akihiko Matsumine
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences University of Fukui, 23-3 Matsuoka Shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| |
Collapse
|
14
|
Han Y, Hong Y, Li L, Li T, Zhang Z, Wang J, Xia H, Tang Y, Shi Z, Han X, Chen T, Liu Q, Zhang M, Zhang K, Hong W, Xue Y. A Transcriptome-Level Study Identifies Changing Expression Profiles for Ossification of the Ligamentum Flavum of the Spine. MOLECULAR THERAPY-NUCLEIC ACIDS 2018; 12:872-883. [PMID: 30161026 PMCID: PMC6120750 DOI: 10.1016/j.omtn.2018.07.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 07/10/2018] [Accepted: 07/31/2018] [Indexed: 01/09/2023]
Abstract
Ossification of the ligamentum flavum (OLF) is a common spinal disorder that causes myelopathy and radiculopathy. Non-coding RNAs (ncRNAs) are involved in numerous pathological processes; however, very few ncRNAs have been identified to be correlated with OLF. Here we compared the expression of lncRNA, mRNA, circRNA, and microRNA in OLF tissues from OLF patients and healthy volunteers through mRNA, lncRNA, and circRNA microarrays and microRNA sequencing. A total of 2,054 mRNAs, 2,567 lncRNAs, 627 circRNAs, and 28 microRNAs (miRNAs) were altered during the process of OLF. qPCR confirmed the differential expression of selected mRNAs and ncRNAs. An lncRNA-mRNA co-expression network, miRNA-mRNA target prediction network, and competing endogenous RNA (ceRNA) network of circRNA-miRNA-mRNA were constructed based on a correlation analysis of the differentially expressed RNA transcripts. Subsequently, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses for the differentially expressed mRNAs and the predicted miRNAs target genes were performed. In addition, a deregulated miRNA-19b-3p-based miRNA-circRNA-lncRNA-mRNA network was confirmed, by gain-of-function and loss-of-function experiments, to function in the process of ossification. Taken together, this study provides a systematic perspective on the potential function of ncRNAs in the pathogenesis of OLF.
Collapse
Affiliation(s)
- Yawei Han
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Yuheng Hong
- School of Medical Imaging, Tianjin Medical University, Tianjin, China
| | - Liandong Li
- Department of Orthopaedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Tengshuai Li
- Department of Orthopaedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Zhen Zhang
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Jingzhao Wang
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Han Xia
- Department of Orthopaedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Yutao Tang
- Department of Orthopaedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Zhemin Shi
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Xiaohui Han
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Ting Chen
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Qi Liu
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Mengxia Zhang
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Kun Zhang
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Wei Hong
- Department of Histology and Embryology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China.
| | - Yuan Xue
- Department of Orthopaedics, Tianjin Medical University General Hospital, Tianjin, China.
| |
Collapse
|
15
|
Overexpression of miR-182 inhibits ossification of ligamentum flavum cells by targeting NAMPT. Exp Cell Res 2018; 367:119-131. [DOI: 10.1016/j.yexcr.2018.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 03/05/2018] [Accepted: 03/06/2018] [Indexed: 12/31/2022]
|
16
|
Yayama T, Mori K, Okumura N, Nishizawa K, Kumagai K, Nakamura A, Imai S. Wnt signaling pathway correlates with ossification of the spinal ligament: A microRNA array and immunohistochemical study. J Orthop Sci 2018; 23:26-31. [PMID: 29102319 DOI: 10.1016/j.jos.2017.09.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 09/17/2017] [Accepted: 10/01/2017] [Indexed: 01/07/2023]
Abstract
BACKGROUND Ossification of the posterior longitudinal ligament or the ligamentum flavum parallels endochondral ossification. Cell differentiation at the ossification front is known to be important during this process, although the factors regulating its initiation and progression are still unclear. The purpose of this study was to identify factors important for the regulation of chondrocyte/osteoblast differentiation during spinal ossification. METHODS Ligamentum flavum tissue was isolated from 25 patients who underwent decompressive surgery for cervical ossification of the posterior longitudinal ligament. Tissue sections were used for in vitro culture to obtain primary cells through migration methods. To identify microRNAs associated with ossification of the posterior longitudinal ligament, cultured cells were prepared from the ligamentous tissue (n = 4; continuous type) or from control ligamentous samples harvested from patients with cervical spondylosis without spinal ossification, and analyzed using a microRNA array. The ligamentous sections were also examined by immunohistochemistry for the expression of candidate microRNA target genes. RESULTS The microRNA array identified 177 factors; 12 of which were expressed at significantly different levels in patients with ossification of the posterior longitudinal ligament compared to those in control patients. The hsa-miR-487b-3p was down-regulated in patients with ossification of the posterior longitudinal ligament, which met the false discovery rate of <0.05. This microRNA was predicted to regulate the expression of genes involved in Wnt signaling. Furthermore, immunohistochemistry of Wnt signaling proteins, including Wnt 3a, LRP5/6, and beta-catenin, revealed positive expression in mesenchymal cells and/or premature chondrocytes at the ossification front. CONCLUSION Our results suggested that down-regulation of miR-487b-3p plays an important role in the initiation of Wnt signaling during the ossification process. Wnt signaling may regulate both chondrocyte and osteoblast differentiation and the specification of endochondral ossification in the pathogenesis of ossification of the posterior longitudinal ligament or the ligamentum flavum.
Collapse
Affiliation(s)
- Takafumi Yayama
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan.
| | - Kanji Mori
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| | - Noriaki Okumura
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| | - Kazuya Nishizawa
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| | - Kosuke Kumagai
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| | - Akira Nakamura
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| | - Shinji Imai
- Department of Orthopedic Surgery, Shiga University of Medical Science, Setatsukinowa, Otsu, Shiga 520-2192, Japan
| |
Collapse
|
17
|
Ning S, Chen Z, Fan D, Sun C, Zhang C, Zeng Y, Li W, Hou X, Qu X, Ma Y, Yu H. Genetic differences in osteogenic differentiation potency in the thoracic ossification of the ligamentum flavum under cyclic mechanical stress. Int J Mol Med 2016; 39:135-143. [PMID: 28004120 PMCID: PMC5179181 DOI: 10.3892/ijmm.2016.2803] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 11/02/2016] [Indexed: 11/05/2022] Open
Abstract
Mechanical stress and genetic factors play important roles in the occurrence of thoracic ossification of ligament flavum (TOLF), which can occur at one, two, or multiple levels of the spine. It is unclear whether single- and multiple-level TOLF differ in terms of osteogenic differentiation potency and osteogenesis-related gene expression under cyclic mechanical stress. This was addressed in the present study using patients with non‑TOLF and single‑ and multiple‑level TOLF (n=8 per group). Primary ligament cells were cultured and osteogenesis was induced by application of cyclic mechanical stress. Osteogenic differentiation was assessed by evaluating alkaline phosphatase (ALP) activity and the mRNA and protein expression of osteogenesis‑related genes, including ALP, bone morphogenetic protein 2 (BMP2), Runt‑related transcription factor‑2 (Runx‑2), osterix, osteopontin (OPN) and osteocalcin. The application of cyclic mechanical stress resulted in higher ALP activity in the multiple‑level than in the single‑level TOLF group, whereas no changes were observed in the non‑TOLF group. The ALP, BMP2, OPN and osterix mRNA levels were higher in the multiple‑level as compared to the single‑level TOLF group, and the levels of all osteogenesis-related genes, apart from Runx2, were higher in the multiple‑level as compared to the non‑TOLF group. The osterix and ALP protein levels were higher in the multiple‑level TOLF group than in the other 2 groups, and were increased with the longer duration of stress. These results highlight the differences in osteogenic differentiation potency between single‑ and multiple‑level TOLF that may be related to the different pathogenesis and genetic background.
Collapse
Affiliation(s)
- Shanglong Ning
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Zhongqiang Chen
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Dongwei Fan
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Chuiguo Sun
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Chi Zhang
- Bone Research Laboratory, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yan Zeng
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Weishi Li
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Xiaofei Hou
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Xiaochen Qu
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Yunlong Ma
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Huilei Yu
- Department of Orthopedics, Peking University Third Hospital, Beijing 100191, P.R. China
| |
Collapse
|
18
|
Shi L, Cai G, Shi J, Guo Y, Chen D, Chen D, Yang H. Ossification of the posterior ligament is mediated by osterix via inhibition of the β-catenin signaling pathway. Exp Cell Res 2016; 349:53-59. [PMID: 27693496 DOI: 10.1016/j.yexcr.2016.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 09/26/2016] [Accepted: 09/28/2016] [Indexed: 11/29/2022]
Abstract
Ossification of the posterior longitudinal ligament (OPLL) involves ectopic calcification of the spinal ligament preferentially at the cervical spine. OPLL is associated with different diseases and occurs by endochondral ossification, which is associated with the activity of different transcription factors. However, the pathogenesis of OPLL remains unclear. Here, we investigated the role of osterix (Osx), a transcription factor that functions downstream of Runx2 and is an important regulator of osteogenesis, in the process of OPLL in a dexamethasone (Dex)-induced model of spinal ligament ossification. Our results showed that Osx is upregulated in patients with OPLL and during the ossification of ligament cells in parallel with the upregulation of osteogenic markers including osteocalcin (OCN), alkaline phosphatase (ALP) and collagen-1 (Col-1). Dex-induced ossification of ligament cells was associated with the downregulation and inactivation of β-catenin, and these effects were offset by Osx knockdown. Activation of β-catenin signaling abolished the effect of Dex on ossification and the upregulation of osteogenic markers. Taken together, our results suggest that OPLL is mediated by Osx via a mechanism involving the Wnt/β-catenin signaling pathway, providing a basis for further research to identify potential targets for the treatment of OPLL.
Collapse
Affiliation(s)
- Lei Shi
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China
| | - Guodong Cai
- Department of Orthopedics, Affiliated Hospital of Taishan Medical University, 706 Taishan Street, Tai'an 271000, Shangdong Province, China
| | - Jiangang Shi
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China
| | - Yongfei Guo
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China
| | - Dechun Chen
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China
| | - Deyu Chen
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China
| | - Haisong Yang
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, No. 415, Fengyang Road, Shanghai 200003, China.
| |
Collapse
|
19
|
miR-203 inhibits the traumatic heterotopic ossification by targeting Runx2. Cell Death Dis 2016; 7:e2436. [PMID: 27787524 PMCID: PMC5133990 DOI: 10.1038/cddis.2016.325] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/09/2016] [Accepted: 09/13/2016] [Indexed: 12/25/2022]
Abstract
Emerging evidence has indicated that dysregulated microRNAs (miRNAs) have an important role in bone formation. However, the pathophysiological role of miRNAs in traumatic heterotopic ossification (HO) remains to be elucidated. Using gene expression profile analyses and subsequent confirmation with real-time PCR assays, we identified the decreased expression of miRNA-203 (miR-203) and increased expression of Runx2 as responses to the development of traumatic HO. We found that miR-203 expression was markedly higher in primary and recurrent HO tissues than in normal bones. The upregulation of miR-203 significantly decreased the level of Runx2 expression, whereas miR-203 downregulation increased Runx2 expression. Mutation of the putative miR-203-binding sites in Runx2 mRNA abolished miR-203-mediated repression of Runx2 3'-untranslated region luciferase reporter activity, indicating that Runx2 is an important target of miR-203 in osteoblasts. We also found that miR-203 is negatively correlated with osteoblast differentiation. Furthermore, in vitro osteoblast activity and matrix mineralization were promoted by antagomir-203 and decreased by agomir-203. We showed that miR-203 suppresses osteoblast activity by inhibiting the β-catenin and extracellular signal-regulated kinase pathways. Moreover, using a tenotomy mouse HO model, we found an inhibitory role of miR-203 in regulating HO in vivo; pretreatment with antagomiR-203 increased the development of HO. These data suggest that miR-203 has a crucial role in suppressing HO by directly targeting Runx2 and that the therapeutic overexpression of miR-203 may be a potential strategy for treating traumatic HO.
Collapse
|
20
|
Qu X, Chen Z, Fan D, Sun C, Zeng Y. MiR-132-3p Regulates the Osteogenic Differentiation of Thoracic Ligamentum Flavum Cells by Inhibiting Multiple Osteogenesis-Related Genes. Int J Mol Sci 2016; 17:ijms17081370. [PMID: 27556448 PMCID: PMC5000765 DOI: 10.3390/ijms17081370] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/08/2016] [Accepted: 08/16/2016] [Indexed: 12/29/2022] Open
Abstract
Ossification of the ligamentum flavum (OLF) is a disorder of heterotopic ossification of spinal ligaments and is the main cause of thoracic spinal canal stenosis. Previous studies suggested that miR-132-3p negatively regulates osteoblast differentiation. However, whether miR-132-3p is involved in the process of OLF has not been investigated. In this study, we investigated the effect of miR-132-3p and its target genes forkhead box O1 (FOXO1), growth differentiation factor 5 (GDF5) and SRY-box 6 (SOX6) on the osteogenic differentiation of ligamentum flavum (LF) cells. We demonstrated that miR-132-3p was down-regulated during the osteogenic differentiation of LF cells and negatively regulated the osteoblast differentiation. Further, miR-132-3p targeted FOXO1, GDF5 and SOX6 and down-regulated the protein expression of these genes. Meanwhile, FOXO1, GDF5 and SOX6 were up-regulated after osteogenic differentiation and the down-regulation of endogenous FOXO1, GDF5 or SOX6 suppressed the osteogenic differentiation of LF cells. In addition, we also found FOXO1, GDF5 and SOX6 expression in the ossification front of OLF samples. Overall, these results suggest that miR-132-3p inhibits the osteogenic differentiation of LF cells by targeting FOXO1, GDF5 and SOX6.
Collapse
Affiliation(s)
- Xiaochen Qu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Zhongqiang Chen
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Dongwei Fan
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Chuiguo Sun
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Yan Zeng
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| |
Collapse
|
21
|
Qu X, Chen Z, Fan D, Sun C, Zeng Y, Hou X, Ning S. Notch signaling pathways in human thoracic ossification of the ligamentum flavum. J Orthop Res 2016; 34:1481-91. [PMID: 27208800 DOI: 10.1002/jor.23303] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 05/19/2016] [Indexed: 02/04/2023]
Abstract
This study investigated the pathological process of Notch signaling in the osteogenesis of ligamentum flavum tissues and cells, and the associated regulatory mechanisms. Notch receptors, ligands, and target genes were identified by quantitative polymerase chain reaction (qPCR) in ligamentum flavum cells and immunohistochemistry in ligamentum flavum sections from ossification of the ligamentum flavum (OLF) patients and controls. The temporospatial expression patterns of JAG1/Notch2/HES1 in human ligamentum flavum cells during osteogenic differentiation were determined by qPCR. Lentiviral vectors for Notch2 overexpression and knockdown were constructed and transfected into ligamentum flavum cells before osteogenic differentiation to examine the function of Notch signaling pathways in the osteogenic differentiation of ligamentum flavum cells. Alkaline phosphatase, Runx2, Osterix, osteocalcin, and osteopontin mRNA levels, alkaline phosphatase activity, and Alizarin Red staining were used as indicators of osteogenic differentiation. JAG1/Notch2/HES1 mRNA levels were up-regulated in ligamentum flavum cells from OLF patients, which increased during osteogenic differentiation. Immunohistochemical analysis suggested positive Notch2 expression at the ossification front. Down-regulation of Notch2 expression decelerated osteogenic differentiation of ligamentum flavum cells, and Notch2 overexpression promoted osteogenic differentiation of ligamentum flavum cells. Expression of Runx2 and Osterix increased in a manner similar to that of Notch2 during osteogenic differentiation of ligamentum flavum cells, and Notch2 knockdown and overexpression influenced their expression levels. Notch signaling plays an important role in OLF, and Notch may affect the osteogenic differentiation of ligamentum flavum cells via interactions with Runx2 and Osterix.© 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1481-1491, 2016.
Collapse
Affiliation(s)
- Xiaochen Qu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Zhongqiang Chen
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Dongwei Fan
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Chuiguo Sun
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Yan Zeng
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Xiaofei Hou
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Shanglong Ning
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| |
Collapse
|
22
|
Cerda IA, Casal GA, Martinez RD, Ibiricu LM. Histological evidence for a supraspinous ligament in sauropod dinosaurs. ROYAL SOCIETY OPEN SCIENCE 2015; 2:150369. [PMID: 26587248 PMCID: PMC4632520 DOI: 10.1098/rsos.150369] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/29/2015] [Indexed: 06/05/2023]
Abstract
Supraspinous ossified rods have been reported in the sacra of some derived sauropod dinosaurs. Although different hypotheses have been proposed to explain the origin of this structure, histological evidence has never been provided to support or reject any of them. In order to establish its origin, we analyse and characterize the microstructure of the supraspinous rod of two sauropod dinosaurs from the Upper Cretaceous of Argentina. The supraspinous ossified rod is almost entirely formed by dense Haversian bone. Remains of primary bone consist entirely of an avascular tissue composed of two types of fibre-like structures, which are coarse and longitudinally (parallel to the main axis of the element) oriented. These structures are differentiated on the basis of their optical properties under polarized light. Very thin fibrous strands are also observed in some regions. These small fibres are all oriented parallel to one another but perpendicular to the element main axis. Histological features of the primary bone tissue indicate that the sacral supraspinous rod corresponds to an ossified supraspinous ligament. The formation of this structure appears to have been a non-pathological metaplastic ossification, possibly induced by the continuous tensile forces applied to the element.
Collapse
Affiliation(s)
- Ignacio A Cerda
- CONICET-Instituto de Investigación en Paleobiología y Geología , Universidad Nacional de Río Negro , Museo Carlos Ameghino, Belgrano 1700, Paraje Pichi Ruca (predio Marabunta) 8300, Cipolletti, Río Negro, Argentina
| | - Gabriel A Casal
- Laboratorio de Paleovertebrados , Universidad Nacional de la Patagonia San Juan Bosco , Ruta Prov. N° 1, Km 4, Comodoro Rivadavia (C.P. 9000), Chubut, Argentina
| | - Rubén D Martinez
- Laboratorio de Paleovertebrados , Universidad Nacional de la Patagonia San Juan Bosco , Ruta Prov. N° 1, Km 4, Comodoro Rivadavia (C.P. 9000), Chubut, Argentina
| | - Lucio M Ibiricu
- CONICET-Centro Nacional Patagónico , Blvd. Alte. Brown 2915, Puerto Madryn, Argentina
| |
Collapse
|
23
|
Clinical characteristics and surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum: a retrospective analysis of 85 cases. Spinal Cord 2015; 54:188-96. [PMID: 26238315 DOI: 10.1038/sc.2015.139] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN A retrospective comparative study. OBJECTIVES To describe the clinical features and radiological findings, to assess the safety and effectiveness of posterior decompressive laminectomy and resection of the ossification of the ligamentum flavum (OLF), and to determine which presurgical and surgical variables were most closely related to postsurgical prognosis of thoracic myelopathy (TM) caused by OLF in China. METHODS Eighty-five patients with the diagnosis of TM caused by OLF received surgical treatment from July 1998 to May 2012. Clinical data were collected from medical and operative records. Correlations between the surgical outcome and various factors were also analyzed. RESULTS All cases were followed up for a mean of 49.2 months (range, 24-190 months) postoperatively. The mean Japanese Orthopaedic Association score was 3.8 points preoperatively and 8.2 points at the final follow-up, yielding a mean recovery rate of 63.0%. Postoperative complications included transient neurological deficits (9 cases), persistent neurological deficits (4 cases), dural tears (17 cases), cerebrospinal fluid leakage (9 cases), wound dehiscence (2 cases) and wound infection (3 cases). The OLF level (middle thoracic), preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were important predictors of surgical outcome. CONCLUSIONS Biomechanical and anatomical factors may have a key role in thoracic OLF progression. Posterior decompressive laminectomy and resection of the OLF can be considered an effective, reliable and safe alternative procedure. The OLF level, preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were confirmed and significantly correlated with the surgical outcome.
Collapse
|
24
|
Hou XF, Fan DW, Sun CG, Chen ZQ. Recombinant human bone morphogenetic protein-2-induced ossification of the ligamentum flavum in rats and the associated global modification of histone H3. J Neurosurg Spine 2014; 21:334-41. [PMID: 24949905 DOI: 10.3171/2014.4.spine13319] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECT The primary object of this investigation was to study recombinant human bone morphogenetic protein-2 (rhBMP-2)-induced ossification of the ligamentum flavum and associated histone H3 modification in a rat model. In an additional set of studies the authors investigated spinal cord and behavioral changes in the same model. METHODS The authors report on 2 separate sets of studies. A total of 90 rats were used for the 2 sets of studies (45 each); in each study, a lyophilized rhBMP-2 and collagen mixture (20 μg rhBMP-2 and 200 μl collagen) was implanted in the lumbar extradural space in 18 rats; another 18 animals were used for a sham-operation control group and underwent implantation of lyophilized collagen without rhBMP-2 at the same level; an additional 9 animals were used as untreated controls. Lumbar spinal samples were harvested from the rhBMP-2 groups and the shamoperation control groups at 1 week, 3 weeks, and 9 weeks after the operation. Samples were also obtained from untreated controls at the same time points. All samples were scanned using micro-CT and then made into paraffinembedded sections. The sections from the first set of 45 rats were stained using elastica van Gieson and toluidine blue, and the expression of histone modifications (H3K9ac, H3K18ac, H3K4me3, and H3K36me3) and osteogenic transcription factors (osterix, Runx2) was detected by immunohistochemistry. In the second set of studies, hindlimb motor function was assessed at 1 week, 3 weeks, and 9 weeks after surgery. After behavioral evaluation, samples were harvested, scanned using micro-CT, and then made into paraffin-embedded sections. The sections were stained using Luxol fast blue. The expression of NeuN was also detected using immunohistochemistry. RESULTS Ossification was seen in the rhBMP-2 group from 1 week after insertion, and the volume of ossified mass increased at 3 and 9 weeks. There was no ossification seen in the sham-surgery and normal controls. The pathological changes of ossification involved ligament degeneration, cartilage formation, and, finally, bone replacement. Spinal cord evaluation showed a significant decrease in white matter content and number of neurons at 9 weeks after operation in the rhBMP-2-treated group (compared with findings in the sham-surgery and control groups as well as findings at the earlier time points in the rhBMP-2 group). Using immunohistochemical staining, histone modifications (H3K9ac, H3K18ac, H3K4me3, and H3K36me3) and osteogenic transcription factors (osterix, Runx2) all were found to be expressed in the fibrocartilage area of the rat ossified ligamentum flavum samples (rhBMP2 group). CONCLUSIONS This rhBMP-2-induced OLF is a typical endochondral ossification, which is similar to clinical OLF. The compressed spinal cord around the ossification site showed signs of a chronic degenerative process. Histone H3 modifications (H3K9ac, H3K18ac, H3K4me3, and H3K36me3) may play an important role in OLF.
Collapse
Affiliation(s)
- Xiao-Fei Hou
- Department of Orthopedics, Peking University Third Hospital, Beijing, China
| | | | | | | |
Collapse
|
25
|
Indian hedgehog signaling promotes chondrocyte differentiation in enchondral ossification in human cervical ossification of the posterior longitudinal ligament. Spine (Phila Pa 1976) 2013; 38:E1388-96. [PMID: 23883825 DOI: 10.1097/brs.0b013e3182a40489] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Histological, immunohistochemical, and immunoblot analyses of the expression of Indian hedgehog (Ihh) signaling in human cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVE To examine the hypothesis that Ihh signaling in correlation with Sox9 and parathyroid-related peptide hormone (PTHrP) facilitates chondrocyte differentiation in enchondral ossification process in human cervical OPLL. SUMMARY OF BACKGROUND DATA In enchondral ossification, certain transcriptional factors regulate cell differentiation. OPLL is characterized by overexpression of these factors and disturbance of the normal cell differentiation process. Ihh signaling is essential for enchondral ossification, especially in chondrocyte hypertrophy. METHODS Samples of ossified ligaments were harvested from 45 patients who underwent anterior cervical decompressive surgery for symptomatic OPLL, and 6 control samples from patients with cervical spondylotic myelopathy/radiculopathy without OPLL. The harvested sections were stained with hematoxylin-eosin and toluidine blue, examined by transmission electron microscopy, and immunohistochemically stained for Ihh, PTHrP, Sox9, type X, XI collagen, and alkaline phosphatase. Immunoblot analysis was performed in cultured cells derived from the posterior longitudinal ligaments in the vicinity of the ossified plaque and examined for the expression of these factors. RESULTS The ossification front in OPLL contained chondrocytes at various differentiation stages, including proliferating chondrocytes in fibrocartilaginous area, hypertrophic chondrocytes around the calcification front, and apoptotic chondrocytes near the ossified area. Immunoreactivity for Ihh and Sox9 was evident in proliferating chondrocytes and was strongly positive for PTHrP in hypertrophic chondrocytes. Mesenchymal cells with blood vessel formation were positive for Ihh, PTHrP, and Sox9. Cultured cells from OPLL tissues expressed significantly higher levels of Ihh, PTHrP, and Sox9 than those in non-OPLL cells. CONCLUSION Our results indicated that overexpression of Ihh signaling promotes abnormal chondrocyte differentiation in enchondral ossification and enhances bone formation in OPLL.
Collapse
|
26
|
Ren L, Hu H, Sun X, Li F, Zhou JJ, Wang YM. The roles of inflammatory cytokines in the pathogenesis of ossification of ligamentum flavum. Am J Transl Res 2013; 5:582-585. [PMID: 24093055 PMCID: PMC3786265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 09/04/2013] [Indexed: 06/02/2023]
Abstract
Ossification of Ligamentum Flavum (OLF) is associated with serious neurologic symptoms including thoracic myelopathy and spinal stenosis. The pathogenesis of thoracic OLF is mainly due to the localized mechanical stress on the ligament induced enchondral ossification. However, despite numerous epidemiological and basic science studies, the mechanism of this process remains unclear. Studies have suggested that inflammatory cytokines, such as IL-6, TNF-α, seem to play a crucial role in OLF. In this review, we summarise the mechanistic information on the roles of inflammation cytokines in OLF and discuss about several therapeutic methods for OLF. Further studies on the role of cytokines in OLF should provide important insights into the designation of therapeutic strategies in preventing human spinal stenosis caused by OLF.
Collapse
Affiliation(s)
- Liang Ren
- Department of Orthopaedics, Shijiazhuang No. 3 HospitalChina
| | - Hongtao Hu
- Department of Orthopaedics, Shijiazhuang No. 3 HospitalChina
| | - Xianze Sun
- Department of Orthopaedics, Shijiazhuang No. 3 HospitalChina
| | - Feng Li
- Department of Orthopaedics, Shijiazhuang No. 3 HospitalChina
| | - Jimmy Jianheng Zhou
- Centre for Kidney Research, Children’s Hospital at WestmeadSydney, NSW 2145, Australia
| | - Yuan Min Wang
- Centre for Kidney Research, Children’s Hospital at WestmeadSydney, NSW 2145, Australia
| |
Collapse
|
27
|
Toledo JA, Isseldyk FV, Re M, Garrote M. Ossification of the ligamentum flavum as cause of thoracic cord compression: Case report of a Latin American man and review of the literature. Surg Neurol Int 2013; 4:119. [PMID: 24083054 PMCID: PMC3784953 DOI: 10.4103/2152-7806.118489] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 07/17/2013] [Indexed: 11/28/2022] Open
Abstract
Background: Ossification of the ligamentum flavum is a widely described pathology in eastern Asia. Cases have been reported in northern Africa, the Middle-East, India, the Caribbean, Europe, and North America, but no cases from Latin America have been published in the literature. It affects mostly elderly men, with a possible association with obesity and type 2 diabetes. Case Description: A 38-year-old previously healthy Latin American male presented to the emergency room department with severe functional disability and a 3/5 paraparesis. Blood reports showed no abnormalities. Computed tomography and magnetic resonance imaging showed a ligamentum flavum ossification with myelopathy. The patient underwent a T3-T9 laminotomy. At hospital discharge, the patient remained with a 3/5 paraparesis, mild hypoesthesia in both lower limbs and bladder incontinence. Rectal sphincter was continent. At 6 months, he was able to walk with a cane, with no sphincter or sensory alterations. Conclusions: Ligamentum flavum ossification is rare. To our understanding, this is the first case reported in the Latin American population.
Collapse
Affiliation(s)
- Javier A Toledo
- Department of Neurosurgery, Hospital Clemente Álvarez, Rosario, Santa Fe, Argentina
| | | | | | | |
Collapse
|
28
|
Chin S, Furukawa KI, Ono A, Asari T, Harada Y, Wada K, Tanaka T, Inaba W, Mizukami H, Motomura S, Yagihashi S, Ishibashi Y. Immunohistochemical localization of mesenchymal stem cells in ossified human spinal ligaments. Biochem Biophys Res Commun 2013; 436:698-704. [PMID: 23770420 DOI: 10.1016/j.bbrc.2013.06.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 06/06/2013] [Indexed: 02/07/2023]
Abstract
Mesenchymal stem cells (MSCs) have been isolated from various tissues and used for elucidating the pathogenesis of numerous diseases. In our previous in vitro study, we showed the existence of MSCs in human spinal ligaments and hypothesized that these MSCs contributed to the pathogenesis of ossification of spinal ligaments. The purpose of this study was to use immunohistochemical techniques to analyze the localization of MSCs in ossified human spinal ligaments in situ. Ossified (OLF) or non-ossified ligamentum flavum (non-OLF) samples from the thoracic vertebra were obtained from patients who had undergone posterior spinal surgery. Serial sections were prepared from paraffin-embedded samples, and double immunofluorescence staining was performed using antibodies against markers for MSCs (CD73, CD90 and CD105), endothelial cells (CD31), pericytes (α-smooth muscle actin), and chondrocytes (S100). Immunolocalization of MSCs was observed in the perivascular area and collagenous matrix in spinal ligaments. Markers for MSCs and pericytes were co-expressed in the perivascular area. Compared with non-OLF, OLF had a large amount of neovascularization in the fragmented ligament matrix, and a high accumulation of MSCs around blood vessels. The prevalence of MSCs in OLF within collagenous matrix was significantly higher than that in non-OLF. Chondrocytes near the ossification front in OLF also presented expression of MSC markers. MSCs may contribute to the ectopic ossification process of OLF through endochondral ossification.
Collapse
Affiliation(s)
- Shunfu Chin
- Department of Pharmacology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Ossified ligamentum flavum causing spinal cord compression in a patient with acromegaly. J Clin Neurosci 2013; 20:1599-603. [PMID: 23706185 DOI: 10.1016/j.jocn.2012.10.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 10/07/2012] [Indexed: 11/23/2022]
Abstract
Acromegaly is a relatively rare neuroendocrine disorder associated with diffuse hypertrophy of bony and soft tissues due to growth hormone hypersecretion from a pituitary adenoma. Acromegaly can also cause numerous pathological changes in the spine, including degenerative osteoarticular disease, axial arthropathy, spinal stenosis, vertebral fracture and diffuse idiopathic skeletal hyperostosis (Forestier's disease). Ossified ligamentum flavum (OLF) is a rare disorder that often presents as thoracic spinal stenosis, but to our knowledge has never been described in patients with acromegaly. Previously, no link has been established between these two entities. We present, to our knowledge, the first reported case of OLF in a patient with acromegaly who presented with thoracic spinal cord compression. OLF is a potential spinal manifestation of acromegaly and should be considered in the differential diagnosis of spinal stenosis or spinal cord compression in the context of growth hormone hypersecretion.
Collapse
|