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de Oliveira G, de Andrade Rodrigues L, Souza da Silva AA, Gouvea LC, Silva RCL, Sasso-Cerri E, Cerri PS. Reduction of osteoclast formation and survival following suppression of cytokines by diacerein in periodontitis. Biomed Pharmacother 2024; 177:117086. [PMID: 39013222 DOI: 10.1016/j.biopha.2024.117086] [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] [Received: 04/23/2024] [Revised: 06/29/2024] [Accepted: 07/01/2024] [Indexed: 07/18/2024] Open
Abstract
Periodontitis causes an increase in several bioactive agents such as interleukins (IL), tumor necrosis factor (TNF)-α and receptor activator of NF-kB ligand (RANKL), which induce the osteoclast formation and activity. Since diacerein exerts anti-TNF-α and anti-IL-1 effects, alleviating bone destruction in osteoarthritis, we investigated whether this drug inhibits the formation and survival of osteoclast in the periodontitis. Rats were distributed into 3 groups: 1) group with periodontitis treated with 100 mg/kg diacerein (PDG), 2) group with periodontitis treated with saline (PSG) and group control (CG) without any treatment. After 7, 15 and 30 days, the maxillae were collected for light and transmission electron microscopy analyses. Gingiva samples were collected to evaluate the mRNA levels for Tnf, Il1b, Tnfsf11 and Tnfrsf11b by RT-qPCR. In PDG, the expression of Tnf and Il1b genes reduced significantly compared to PSG, except for Tnf expression at 7 days. The number of osteoclasts reduced significantly in the PDG in comparison with PSG at 7 and 15 days. In all periods, the IL-6 immunoexpression, RANKL/OPG immunoexpression and mRNA levels of Tnfsf11/Tnfrsf11b ratio were significantly lower in PDG than in PSG. PDG exhibited significantly higher frequency of TUNEL-positive osteoclasts than in PSG and CG at all time points. Osteoclasts with caspase-3-immunolabelled cytoplasm and nuclei with masses of condensed chromatin were observed in PDG, confirming osteoclast apoptosis. Diacerein inhibits osteoclastogenesis by decreasing Tnf and Il1b mRNA levels, resulting in decreased RANKL/OPG ratio, and induces apoptosis in osteoclasts of alveolar process of rat molars with periodontitis.
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Affiliation(s)
- Gabriella de Oliveira
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil
| | - Lucas de Andrade Rodrigues
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil
| | | | - Lays Cristina Gouvea
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil
| | - Renata Cristina Lima Silva
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil
| | - Estela Sasso-Cerri
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil
| | - Paulo Sérgio Cerri
- São Paulo State University (UNESP), School of Dentistry, Laboratory of Histology and Embryology, Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry, Araraquara, SP, Brazil.
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Condi FLDF, Fuchs LFP, Carvalho KC, Baracat EC. Treatment with Raloxifene Induces the Expression of Kisspeptin, Insulin, and Androgen Receptors in Bones of Castrated Adult Female Rats. Rev Bras Ortop 2024; 59:e228-e234. [PMID: 38606141 PMCID: PMC11006519 DOI: 10.1055/s-0044-1779319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 06/26/2023] [Indexed: 04/13/2024] Open
Abstract
Objective To evaluate the effects of estrogen, raloxifene and genistein on the expression of KISS1 (kisspeptin), KISS1R (kisspeptin receptor), AR (androgen receptor) and INSR (insulin receptor) in the bones of ovariectomized rats. Methods Forty-eight adult rats were randomly divided into 6 groups, containing 8 animals each: G1-nonovariectomized control; G2-ovariectomized and treated with conjugated equine estrogens (50 µg/Kg/day); G3-ovariectomized and treated with raloxifene (0.75 mg/kg/day); G4-ovariectomized animal that received soy extract with genistein (300 mg/kg/day); G5-ovariectomized animal that received estrogen and genistein; and G6-ovariectomized animal that received estrogen and raloxifene. Three months after surgery, the castrated animals received the drugs orally daily for 120 days. All animals were sacrificed after this period, by deepening the anesthesia. The left tibia was removed for total RNA extraction and analysis of gene expression of KISS1 , KISS1R , AR and INSR , by quantitative real-time polymerase chain reaction (qRT-PCR). Results KISS1 was not detected in any of the treated groups. KISS1R , INSR and AR showed higher expression in the G3 group ( p < 0.001), while lower levels of transcripts for these genes were observed in G4 and G5. G2 animals showed hypoexpression of the evaluated genes. Conclusion The results indicate that raloxifene, alone or combined with estrogen, was able to induce the expression of genes associated with the recovery of bone tissue homeostasis in ovariectomized rats.
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Affiliation(s)
| | - Luiz Fernando Portugal Fuchs
- Departamento de Ginecologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - Katia Candido Carvalho
- Laboratório de Ginecologia Estrutural e Molecular (LIM 58), Disciplina de Ginecologia, Departamento de Obstetrícia e Ginecologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (HCFMUSP), São Paulo, SP, Brasil
| | - Edmund Chada Baracat
- Laboratório de Ginecologia Estrutural e Molecular (LIM 58), Disciplina de Ginecologia, Departamento de Obstetrícia e Ginecologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (HCFMUSP), São Paulo, SP, Brasil
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The Immunomodulatory and Regenerative Effect of Biodentine™ on Human THP-1 Cells and Dental Pulp Stem Cells: In Vitro Study. BIOMED RESEARCH INTERNATIONAL 2022; 2022:2656784. [PMID: 36093401 PMCID: PMC9462999 DOI: 10.1155/2022/2656784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/09/2022] [Accepted: 08/18/2022] [Indexed: 11/17/2022]
Abstract
Background Pulp tissue affected by deep caries and trauma can be protected by vital pulp therapies in which pulp regeneration success depends on the degree of pulp inflammation and the presence of regenerative signals. Reparative dentinogenesis requires dental pulp stem cell (DPSC) activity which can be stimulated by many bioactive molecules to repair the dentine, mediating a balance between the inflammatory response and the reparative events. Therefore, this study was performed in order to investigate the immune-inflammatory effect of Biodentine capping material on DPSCs and macrophages. Method THP-1, a human monocytic cell line, was differentiated to macrophages, and flow cytometry was used to analyze the expressions of specific macrophage markers. LPS-mediated infection was created for macrophages and DPSCs followed by treatment with Biodentine. CBA array was used to investigate the cytokine secretion followed by qPCR. Migration potential of treated DPSCs was also determined. Results Our results showed that THP-1 cell line was successfully differentiated into macrophages as shown by surface marker expression. CBA array and qPCR results showed that Biodentine-treated DPSCs and macrophages upregulated anti-inflammatory cytokines and downregulated proinflammatory cytokines. Also, Biodentine enhances the migration potential of treated DPSCs. Conclusion Biodentine capping material mediated the polarization of M1 to M2 macrophages suggestive of tissue repair properties of macrophages and enhanced the anti-inflammatory cytokines of DPSCs responsible for dentine-pulp regeneration.
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Ahmadzadeh K, Vanoppen M, Rose CD, Matthys P, Wouters CH. Multinucleated Giant Cells: Current Insights in Phenotype, Biological Activities, and Mechanism of Formation. Front Cell Dev Biol 2022; 10:873226. [PMID: 35478968 PMCID: PMC9035892 DOI: 10.3389/fcell.2022.873226] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/17/2022] [Indexed: 12/21/2022] Open
Abstract
Monocytes and macrophages are innate immune cells with diverse functions ranging from phagocytosis of microorganisms to forming a bridge with the adaptive immune system. A lesser-known attribute of macrophages is their ability to fuse with each other to form multinucleated giant cells. Based on their morphology and functional characteristics, there are in general three types of multinucleated giant cells including osteoclasts, foreign body giant cells and Langhans giant cells. Osteoclasts are bone resorbing cells and under physiological conditions they participate in bone remodeling. However, under pathological conditions such as rheumatoid arthritis and osteoporosis, osteoclasts are responsible for bone destruction and bone loss. Foreign body giant cells and Langhans giant cells appear only under pathological conditions. While foreign body giant cells are found in immune reactions against foreign material, including implants, Langhans giant cells are associated with granulomas in infectious and non-infectious diseases. The functionality and fusion mechanism of osteoclasts are being elucidated, however, our knowledge on the functions of foreign body giant cells and Langhans giant cells is limited. In this review, we describe and compare the phenotypic aspects, biological and functional activities of the three types of multinucleated giant cells. Furthermore, we provide an overview of the multinucleation process and highlight key molecules in the different phases of macrophage fusion.
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Affiliation(s)
- Kourosh Ahmadzadeh
- Laboratory of Immunobiology, Department Microbiology and Immunology, Rega Institute, KU Leuven – University of Leuven, Leuven, Belgium
- *Correspondence: Kourosh Ahmadzadeh, ; Carine Helena Wouters,
| | - Margot Vanoppen
- Laboratory of Immunobiology, Department Microbiology and Immunology, Rega Institute, KU Leuven – University of Leuven, Leuven, Belgium
| | - Carlos D. Rose
- Division of Pediatric Rheumatology Nemours Children’s Hospital, Thomas Jefferson University, Philadelphia, PA, United States
| | - Patrick Matthys
- Laboratory of Immunobiology, Department Microbiology and Immunology, Rega Institute, KU Leuven – University of Leuven, Leuven, Belgium
| | - Carine Helena Wouters
- Laboratory of Immunobiology, Department Microbiology and Immunology, Rega Institute, KU Leuven – University of Leuven, Leuven, Belgium
- Division Pediatric Rheumatology, UZ Leuven, Leuven, Belgium
- European Reference Network for Rare Immunodeficiency, Autoinflammatory and Autoimmune Diseases (RITA) at University Hospital Leuven, Leuven, Belgium
- *Correspondence: Kourosh Ahmadzadeh, ; Carine Helena Wouters,
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da Silva Sasso GR, Florencio-Silva R, Sasso-Cerri E, Gil CD, de Jesus Simões M, Cerri PS. Spatio-temporal immunolocalization of VEGF-A, Runx2, and osterix during the early steps of intramembranous ossification of the alveolar process in rat embryos. Dev Biol 2021; 478:133-143. [PMID: 34245724 DOI: 10.1016/j.ydbio.2021.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/10/2021] [Accepted: 07/03/2021] [Indexed: 12/14/2022]
Abstract
Vascular endothelial growth factor A (VEGF-A) is expressed by several cell types and is a crucial factor for angiogenic-osteogenic coupling. However, the immunolocalization of VEGF-A during the early stages of the alveolar process formation remains underexplored. Thus, we analyzed the spatio-temporal immunolocalization of VEGF-A and its relationship with Runt-related transcription factor 2 (Runx2) and osterix (Osx) during the early steps of intramembranous ossification of the alveolar process in rat embryos. Embryo heads (E) of 16, 18 and 20-day-old rats were processed for paraffin embedding. Histomorphometry and immunohistochemistry to detect VEGF-A, Runx2, and Osx (osteoblast differentiation markers) were performed. The volume density of bone tissue including bone cells and blood vessels increased significantly in E18 and E20. Cells showing high VEGF-A immunoreactivity were initially observed within a perivascular niche in the ectomesenchyme; afterwards, these cells were diffusely located near bone formation sites. Runx2-and Osx-immunopositive cells were observed in corresponded regions of cells showing strong VEGF-A immunoreactivity. Although these immunostained cells were observed in all specimens, this immunolocalization pattern was more evident in E16 specimens and gradually decreased in E18 and E20 specimens. Double immunofluorescence labelling showed intracellular co-localization of Osx and VEGF-A in cells surrounding the developing alveolar process, indicating a crucial role of VEGF-A in osteoblast differentiation. Our results showed VEGF-A immunoexpression in osteoblasts and its precursors during the maxillary alveolar process formation of rat embryos. Moreover, the VEGF-A-positive cells located within a perivascular niche at the early stages of the alveolar process development suggest a crosstalk between endothelium and ectomesenchymal cells, reinforcing the angiogenic-osteogenic coupling in this process.
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Affiliation(s)
- Gisela Rodrigues da Silva Sasso
- Universidade Federal de São Paulo - UNIFESP, Escola Paulista de Medicina - EPM, Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, São Paulo, SP, Brazil; Universidade Federal de São Paulo - UNIFESP, Escola Paulista de Medicina - EPM, Departamento de Ginecologia, São Paulo, SP, Brazil
| | - Rinaldo Florencio-Silva
- Universidade Federal de São Paulo - UNIFESP, Escola Paulista de Medicina - EPM, Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, São Paulo, SP, Brazil
| | - Estela Sasso-Cerri
- São Paulo State University (UNESP), School of Dentistry, Araraquara - Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry - Laboratory of Histology and Embryology, Araraquara, SP, Brazil
| | - Cristiane Damas Gil
- Universidade Federal de São Paulo - UNIFESP, Escola Paulista de Medicina - EPM, Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, São Paulo, SP, Brazil
| | - Manuel de Jesus Simões
- Universidade Federal de São Paulo - UNIFESP, Escola Paulista de Medicina - EPM, Departamento de Morfologia e Genética, Disciplina de Histologia e Biologia Estrutural, São Paulo, SP, Brazil
| | - Paulo Sérgio Cerri
- São Paulo State University (UNESP), School of Dentistry, Araraquara - Department of Morphology, Genetics, Orthodontics and Pediatric Dentistry - Laboratory of Histology and Embryology, Araraquara, SP, Brazil.
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Biodentine and MTA modulate immunoinflammatory response favoring bone formation in sealing of furcation perforations in rat molars. Clin Oral Investig 2018; 23:1237-1252. [DOI: 10.1007/s00784-018-2550-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/27/2018] [Indexed: 12/12/2022]
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Saas P, Bonnefoy F, Toussirot E, Perruche S. Harnessing Apoptotic Cell Clearance to Treat Autoimmune Arthritis. Front Immunol 2017; 8:1191. [PMID: 29062314 PMCID: PMC5640883 DOI: 10.3389/fimmu.2017.01191] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 09/08/2017] [Indexed: 12/14/2022] Open
Abstract
Early-stage apoptotic cells possess immunomodulatory properties. Proper apoptotic cell clearance during homeostasis has been shown to limit subsequent immune responses. Based on these observations, early-stage apoptotic cell infusion has been used to prevent unwanted inflammatory responses in different experimental models of autoimmune diseases or transplantation. Moreover, this approach has been shown to be feasible without any toxicity in patients undergoing allogeneic hematopoietic cell transplantation to prevent graft-versus-host disease. However, whether early-stage apoptotic cell infusion can be used to treat ongoing inflammatory disorders has not been reported extensively. Recently, we have provided evidence that early-stage apoptotic cell infusion is able to control, at least transiently, ongoing collagen-induced arthritis. This beneficial therapeutic effect is associated with the modulation of antigen-presenting cell functions mainly of macrophages and plasmacytoid dendritic cells, as well as the induction of collagen-specific regulatory CD4+ T cells (Treg). Furthermore, the efficacy of this approach is not altered by the association with two standard treatments of rheumatoid arthritis (RA), methotrexate and tumor necrosis factor (TNF) inhibition. Here, in the light of these observations and recent data of the literature, we discuss the mechanisms of early-stage apoptotic cell infusion and how this therapeutic approach can be transposed to patients with RA.
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Affiliation(s)
- Philippe Saas
- INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Fédération Hospitalo-Universitaire INCREASE, LabEx LipSTIC, Université Bourgogne Franche-Comté, Besançon, France.,INSERM CIC-1431, University Hospital of Besançon, Clinical Investigation Center in Biotherapy, Fédération Hospitalo-Universitaire INCREASE, LabEx LipSTIC, Besançon, France
| | - Francis Bonnefoy
- INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Fédération Hospitalo-Universitaire INCREASE, LabEx LipSTIC, Université Bourgogne Franche-Comté, Besançon, France
| | - Eric Toussirot
- INSERM CIC-1431, University Hospital of Besançon, Clinical Investigation Center in Biotherapy, Fédération Hospitalo-Universitaire INCREASE, LabEx LipSTIC, Besançon, France.,Department of Rheumatology, University Hospital of Besançon, Besançon, France.,Department of Therapeutics, Université Bourgogne Franche-Comté, UPRES EA 4266, Pathogenic Agents and Inflammation, Besancon, France
| | - Sylvain Perruche
- INSERM, EFS BFC, UMR1098, Interactions Hôte-Greffon-Tumeur/Ingénierie Cellulaire et Génique, Fédération Hospitalo-Universitaire INCREASE, LabEx LipSTIC, Université Bourgogne Franche-Comté, Besançon, France
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Hou T, Liu Y, Kolba N, Guo D, He H. Desalted Duck Egg White Peptides Promote Calcium Uptake and Modulate Bone Formation in the Retinoic Acid-Induced Bone Loss Rat and Caco-2 Cell Model. Nutrients 2017; 9:nu9050490. [PMID: 28498349 PMCID: PMC5452220 DOI: 10.3390/nu9050490] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/27/2017] [Accepted: 05/10/2017] [Indexed: 02/03/2023] Open
Abstract
Desalted duck egg white peptides (DPs) have been proven to promote calcium uptake in Caco-2 cells and rats treated with a calcium-deficient diet. The retinoic acid-induced bone loss model was used to evaluate the effect of DPs on calcium absorption and bone formation. Three-month-old Wistar female rats were treated with 0.9% saline, DPs (800 mg/kg), or alendronate (5 mg/kg) for three weeks immediately after retinoic acid treatment (80 mg/kg) once daily for two weeks. The model group was significantly higher in serum bone alkaline phosphatase than the other three groups (p < 0.05), but lower in calcium absorption rate, serum osteocalcin, bone weight index, bone calcium content, bone mineral density, and bone max load. After treatment with DPs or alendronate, the absorption rate increased and some serum and bone indices recovered. The morphology results indicated bone tissue form were ameliorated and numbers of osteoclasts decreased after supplementation with DPs or alendronate. The in vitro study showed that the transient receptor potential vanilloid 6 (TRPV6) calcium channel was the main transport pathway of both DPs and Val-Ser-Glu-Glu peptitde (VSEE), which was identified from DPs. Our results indicated that DPs could be a promising alternative to current therapeutic agents for bone loss because of the promotion of calcium uptake and regulation of bone formation.
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Affiliation(s)
- Tao Hou
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
- Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
| | - Yanshuang Liu
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
- Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
| | - Nikolai Kolba
- USDA-ARS, Robert W. Holley Center for Agriculture and Health, Cornell University, Ithaca, NY 14850, USA.
| | - Danjun Guo
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
- Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
| | - Hui He
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
- Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
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de Oliveira PA, de Pizzol-Júnior JP, Longhini R, Sasso-Cerri E, Cerri PS. Cimetidine Reduces Interleukin-6, Matrix Metalloproteinases-1 and -9 Immunoexpression in the Gingival Mucosa of Rat Molars With Induced Periodontal Disease. J Periodontol 2016; 88:100-111. [PMID: 27587368 DOI: 10.1902/jop.2016.160132] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Histamine seems to act, via H2 receptor, on inflammatory processes by stimulating interleukin (IL)-6 and matrix metalloproteinase (MMP) release. As cimetidine is an H2 receptor antagonist, the authors hypothesize that this antiulcer drug reduces IL-6, MMP-1, and MMP-9 immunoexpression in gingiva with induced periodontal disease (PD). To confirm a possible modulatory role of IL-6 on MMPs, the relationship between IL-6/MMP-1 and IL-6/MMP-9 immunoexpression was evaluated. METHODS Forty-six male rats were distributed into the cimetidine group (CimG: received daily intraperitoneal injections of 100 mg/kg of body weight of cimetidine) or the saline group (SG). PD was induced by cotton ligature around the maxillary left first molars (PDSG and PDCimG). The right molars were used as controls (SG and CimG). After 7, 15, 30, and 50 days, maxillary fragments were processed for paraffin embedding or for transmission electron microscopy. Tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts in the alveolar process surface and number of IL-6, MMP-1, and MMP-9-immunolabeled cells in the gingival mucosa were quantified. Statistical analyses were performed (P ≤0.05). RESULTS In PDSG and PDCimG, gingival mucosa exhibited few collagen fibers among numerous inflammatory cells. In PDCimG, the number of TRAP-positive osteoclasts and IL-6, MMP-1, and MMP-9-immunolabeled cells was significantly lower than in PDSG at all periods. A positive correlation between IL-6/MMP-1 and IL-6/MMP-9 was detected in PDSG and PDCimG. CONCLUSION Cimetidine decreases bone loss through reduction of osteoclast number and induces reduction of IL-6, MMP-1, and MMP-9 immunoexpression, reinforcing the idea that the beneficial effect of cimetidine in PD may be due to reduction of IL-6 immunolabeling in the inflamed gingival mucosa.
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Affiliation(s)
| | - José Paulo de Pizzol-Júnior
- Department of Morphology and Genetics, Federal University of São Paulo, São Paulo, Brazil.,Department of Morphology, Dental School, Laboratory of Histology and Embryology, University Estadual Paulista, Araraquara, São Paulo, Brazil
| | - Renata Longhini
- Department of Morphology and Genetics, Federal University of São Paulo, São Paulo, Brazil
| | - Estela Sasso-Cerri
- Department of Morphology, Dental School, Laboratory of Histology and Embryology, University Estadual Paulista, Araraquara, São Paulo, Brazil
| | - Paulo Sérgio Cerri
- Department of Morphology, Dental School, Laboratory of Histology and Embryology, University Estadual Paulista, Araraquara, São Paulo, Brazil
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Mello ASDS, dos Santos PL, Marquesi A, Queiroz TP, Margonar R, de Souza Faloni AP. Some aspects of bone remodeling around dental implants. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.piro.2015.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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de Pizzol Júnior JP, Sasso-Cerri E, Cerri PS. Apoptosis and reduced microvascular density of the lamina propria during tooth eruption in rats. J Anat 2015; 227:487-96. [PMID: 26228092 DOI: 10.1111/joa.12359] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2015] [Indexed: 12/12/2022] Open
Abstract
During tooth eruption, structural and functional changes must occur in the lamina propria to establish the eruptive pathway. In this study, we evaluate the structural changes that occur during lamina propria degradation and focus these efforts on apoptosis and microvascular density. Fragments of maxilla containing the first molars from 9-, 11-, 13- and 16-day-old rats were fixed, decalcified and embedded in paraffin. The immunohistochemical detection of vascular endothelial growth factor (VEGF), caspase-3 and MAC387 (macrophage marker), and the TUNEL method were applied to the histological molar sections. The numerical density of TUNEL-positive cells and VEGF-positive blood vessel profiles were also obtained. Data were statistically evaluated using a one-way anova with the post-hoc Kruskal-Wallis or Tukey test and a significance level of P ≤ 0.05. Fragments of maxilla were embedded in Araldite for analysis under transmission electron microscopy (TEM). TUNEL-positive structures, fibroblasts with strongly basophilic nuclei and macrophages were observed in the lamina propria at all ages. Using TEM, we identified processes of fibroblasts or macrophages surrounding partially apoptotic cells. We found a high number of apoptotic cells in 11-, 13- and 16-day-old rats. We observed VEGF-positive blood vessel profiles at all ages, but a significant decrease in the numerical density was found in 13- and 16-day-old rats compared with 9-day-old rats. Therefore, the establishment of the eruptive pathway during the mucosal penetration stage depends on cell death by apoptosis, the phagocytic activity of fibroblasts and macrophages, and a decrease in the microvasculature due to vascular cell death. These data point to the importance of vascular rearrangement and vascular neoformation during tooth eruption and the development of oral mucosa.
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Affiliation(s)
| | - Estela Sasso-Cerri
- Dental School - Laboratory of Histology and Embryology, UNESP - São Paulo State University, Araraquara, SP, Brazil
| | - Paulo Sérgio Cerri
- Dental School - Laboratory of Histology and Embryology, UNESP - São Paulo State University, Araraquara, SP, Brazil
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Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells. BIOMED RESEARCH INTERNATIONAL 2015; 2015:421746. [PMID: 26247020 PMCID: PMC4515490 DOI: 10.1155/2015/421746] [Citation(s) in RCA: 911] [Impact Index Per Article: 101.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 04/30/2015] [Accepted: 05/04/2015] [Indexed: 02/06/2023]
Abstract
Bone tissue is continuously remodeled through the concerted actions of bone cells, which include bone resorption by osteoclasts and bone formation by osteoblasts, whereas osteocytes act as mechanosensors and orchestrators of the bone remodeling process. This process is under the control of local (e.g., growth factors and cytokines) and systemic (e.g., calcitonin and estrogens) factors that all together contribute for bone homeostasis. An imbalance between bone resorption and formation can result in bone diseases including osteoporosis. Recently, it has been recognized that, during bone remodeling, there are an intricate communication among bone cells. For instance, the coupling from bone resorption to bone formation is achieved by interaction between osteoclasts and osteoblasts. Moreover, osteocytes produce factors that influence osteoblast and osteoclast activities, whereas osteocyte apoptosis is followed by osteoclastic bone resorption. The increasing knowledge about the structure and functions of bone cells contributed to a better understanding of bone biology. It has been suggested that there is a complex communication between bone cells and other organs, indicating the dynamic nature of bone tissue. In this review, we discuss the current data about the structure and functions of bone cells and the factors that influence bone remodeling.
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Chen H, Senda T, Kubo KY. The osteocyte plays multiple roles in bone remodeling and mineral homeostasis. Med Mol Morphol 2015; 48:61-8. [PMID: 25791218 DOI: 10.1007/s00795-015-0099-y] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 03/04/2015] [Indexed: 12/17/2022]
Abstract
Osteocytes are the most abundant cells in bone and are the major orchestrators of bone remodeling and mineral homeostasis. They possess a specialized cellular morphology and a unique molecular feature. Osteocytes are a stellate shape with numerous long, slender dendritic processes. The osteocyte cell body resides in the bone matrix of the lacuna and the dendritic processes extend within the canaliculi to adjacent osteocytes and other cells on the bone surface. Osteocytes form extensive intercellular network to sense and respond to environmental mechanical stimulus by the lacunar-canalicular system and gap junction. Osteocytes are long-lived bone cells. They can undergo apoptosis, which may have specific regulatory effects on osteoclastic bone resorption. Osteocytes can secrete several molecules, including sclerostin, receptor activator of nuclear factor κB ligand and fibroblast growth factor 23 to regulate osteoblastic bone formation, osteoclastic bone resorption and mineral homeostasis. A deeper understanding of the complex mechanisms that mediate the control of osteoblast and osteoclast function by osteocytes may identify new osteocyte-derived molecules as potential pharmacological targets for treating osteoporosis and other skeletal diseases.
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Affiliation(s)
- Huayue Chen
- Department of Anatomy, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan,
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14
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Longhini R, Aparecida de Oliveira P, Sasso-Cerri E, Cerri PS. Cimetidine Reduces Alveolar Bone Loss in Induced Periodontitis in Rat Molars. J Periodontol 2014; 85:1115-25. [DOI: 10.1902/jop.2013.130453] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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15
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Lee DE, Kim JH, Choi SH, Cha JH, Bak EJ, Yoo YJ. Periodontitis mainly increases osteoclast formation via enhancing the differentiation of quiescent osteoclast precursors into osteoclasts. J Periodontal Res 2014; 50:256-64. [DOI: 10.1111/jre.12203] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2014] [Indexed: 12/25/2022]
Affiliation(s)
- D.-E. Lee
- Department of Oral Biology; College of Dentistry; Yonsei University; Seoul South Korea
- Department of Applied Life Science; The Graduate School; Yonsei University; Seoul South Korea
- Brain Korea 21 Plus Project; College of Dentistry; Yonsei University; Seoul South Korea
| | - J.-H. Kim
- Department of Oral Biology; College of Dentistry; Yonsei University; Seoul South Korea
| | - S.-H. Choi
- Department of Periodontology; Research Institute for Periodontal Regeneration; College of Dentistry; Yonsei University; Seoul South Korea
| | - J.-H. Cha
- Department of Oral Biology; College of Dentistry; Yonsei University; Seoul South Korea
- Department of Applied Life Science; The Graduate School; Yonsei University; Seoul South Korea
- Brain Korea 21 Plus Project; College of Dentistry; Yonsei University; Seoul South Korea
- Oral Cancer Research Institute; College of Dentistry; Yonsei University; Seoul South Korea
| | - E.-J. Bak
- Oral Cancer Research Institute; College of Dentistry; Yonsei University; Seoul South Korea
| | - Y.-J. Yoo
- Department of Oral Biology; College of Dentistry; Yonsei University; Seoul South Korea
- Department of Applied Life Science; The Graduate School; Yonsei University; Seoul South Korea
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16
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Oh KC, Moon HS, Lee JH, Park YB, Kim JH. Effects of alendronate on the peri-implant bone in rats. Oral Dis 2014; 21:248-56. [PMID: 24824878 DOI: 10.1111/odi.12258] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 04/26/2014] [Accepted: 04/28/2014] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The purpose of this study was to determine the effects of alendronate on the peri-implant bone in rat maxillae with the aid of micro-computed tomographic, histologic, and biochemical analyses. MATERIALS AND METHODS Thirty-six male Sprague-Dawley rats were used. After extraction of the maxillary first molars, each rat was given periodic subcutaneous injections of either alendronate (alendronate group) or saline (control group). Customized implants were placed bilaterally 4 weeks after these injections. The rats were sacrificed at either 4, 8, or 12 weeks after implantation (4-, 8-, and 12-week groups, respectively; n = 6 rats per group). Microcomputed tomographic and histologic analyses were conducted for all rats. Biochemical analyses were performed at four time points for the 12-week groups. RESULTS There were no significant differences between the groups on microcomputed tomographic and histologic analyses. All of the measured biochemical parameters tended to decrease over time, with significant differences among some time points within each group. The serum osteocalcin level was significantly lower in the 12-week alendronate group than in the control group (P < 0.05). CONCLUSIONS Three approaches were utilized in evaluating the effects of alendronate. It appears serum osteocalcin levels may serve as an adjuvant marker for this purpose, although further studies are required to confirm this.
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Affiliation(s)
- K C Oh
- Department of Prosthodontics, Yonsei University College of Dentistry, Seoul, Korea
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17
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Abstract
Studies from the 1950s and 1960s already recognize the fact that osteocytes, although long living cells, die, as evidenced by accumulation of osteocytic lacunae devoid of cells. More recently, it was demonstrated that these cells die by apoptosis. The rate of osteocyte apoptosis is regulated by the age of the bone, as well as by systemic hormones, local growth factors, cytokines, pharmacological agents, and mechanical forces. Apoptotic osteocytes, in turn, recruit osteoclasts to initiate targeted bone resorption. This results in the removal of "dead" bone and may improve the mechanical properties of the skeleton. However, the molecular regulators of osteocyte survival and targeted bone remodeling are not completely known. In this review, the current knowledge on the molecular mechanism that lead to osteocyte death or survival, and the signals that mediate targeted bone resorption is discussed.
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Affiliation(s)
- Lilian I Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS-5035, Indianapolis, IN, USA,
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18
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Schaffler MB, Cheung WY, Majeska R, Kennedy O. Osteocytes: master orchestrators of bone. Calcif Tissue Int 2014; 94:5-24. [PMID: 24042263 PMCID: PMC3947191 DOI: 10.1007/s00223-013-9790-y] [Citation(s) in RCA: 305] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 08/22/2013] [Indexed: 12/12/2022]
Abstract
Osteocytes comprise the overwhelming majority of cells in bone and are its only true "permanent" resident cell population. In recent years, conceptual and technological advances on many fronts have helped to clarify the role osteocytes play in skeletal metabolism and the mechanisms they use to perform them. The osteocyte is now recognized as a major orchestrator of skeletal activity, capable of sensing and integrating mechanical and chemical signals from their environment to regulate both bone formation and resorption. Recent studies have established that the mechanisms osteocytes use to sense stimuli and regulate effector cells (e.g., osteoblasts and osteoclasts) are directly coupled to the environment they inhabit-entombed within the mineralized matrix of bone and connected to each other in multicellular networks. Communication within these networks is both direct (via cell-cell contacts at gap junctions) and indirect (via paracrine signaling by secreted signals). Moreover, the movement of paracrine signals is dependent on the movement of both solutes and fluid through the space immediately surrounding the osteocytes (i.e., the lacunar-canalicular system). Finally, recent studies have also shown that the regulatory capabilities of osteocytes extend beyond bone to include a role in the endocrine control of systemic phosphate metabolism. This review will discuss how a highly productive combination of experimental and theoretical approaches has managed to unearth these unique features of osteocytes and bring to light novel insights into the regulatory mechanisms operating in bone.
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Affiliation(s)
- Mitchell B. Schaffler
- University: City College of New York, Department: Biomedical Engineering, Phone: 212-650-5070, Fax: 212-650-6727
| | - Wing-Yee Cheung
- University: City College of New York, Department: Biomedical Engineering
| | - Robert Majeska
- University: City College of New York, Department: Biomedical Engineering
| | - Oran Kennedy
- University: New York University, Department: Orthopaedic Surgery
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19
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Enzymatically Synthesized Inorganic Polymers as Morphogenetically Active Bone Scaffolds. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 313:27-77. [DOI: 10.1016/b978-0-12-800177-6.00002-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Wang X, Schröder HC, Feng Q, Draenert F, Müller WEG. The deep-sea natural products, biogenic polyphosphate (Bio-PolyP) and biogenic silica (Bio-Silica), as biomimetic scaffolds for bone tissue engineering: fabrication of a morphogenetically-active polymer. Mar Drugs 2013; 11:718-46. [PMID: 23528950 PMCID: PMC3705367 DOI: 10.3390/md11030718] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/04/2013] [Accepted: 02/06/2013] [Indexed: 12/12/2022] Open
Abstract
Bone defects in human, caused by fractures/nonunions or trauma, gain increasing impact and have become a medical challenge in the present-day aging population. Frequently, those fractures require surgical intervention which ideally relies on autografts or suboptimally on allografts. Therefore, it is pressing and likewise challenging to develop bone substitution materials to heal bone defects. During the differentiation of osteoblasts from their mesenchymal progenitor/stem cells and of osteoclasts from their hemopoietic precursor cells, a lineage-specific release of growth factors and a trans-lineage homeostatic cross-talk via signaling molecules take place. Hence, the major hurdle is to fabricate a template that is functioning in a way mimicking the morphogenetic, inductive role(s) of the native extracellular matrix. In the last few years, two naturally occurring polymers that are produced by deep-sea sponges, the biogenic polyphosphate (bio-polyP) and biogenic silica (bio-silica) have also been identified as promoting morphogenetic on both osteoblasts and osteoclasts. These polymers elicit cytokines that affect bone mineralization (hydroxyapatite formation). In this manner, bio-silica and bio-polyP cause an increased release of BMP-2, the key mediator activating the anabolic arm of the hydroxyapatite forming cells, and of RANKL. In addition, bio-polyP inhibits the progression of the pre-osteoclasts to functionally active osteoclasts. Based on these findings, new bioinspired strategies for the fabrication of bone biomimetic templates have been developed applying 3D-printing techniques. Finally, a strategy is outlined by which these two morphogenetically active polymers might be used to develop a novel functionally active polymer.
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Affiliation(s)
- Xiaohong Wang
- ERC Advanced Investigator Grant Research Group at Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany; E-Mail:
- National Research Center for Geoanalysis, Chinese Academy of Geological Sciences, 26 Baiwanzhuang Dajie, 100037 Beijing, China
| | - Heinz C. Schröder
- ERC Advanced Investigator Grant Research Group at Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany; E-Mail:
| | - Qingling Feng
- Department of Materials Science and Engineering, Tsinghua University, 100084 Beijing, China; E-Mail:
| | - Florian Draenert
- Department and Clinic for Oral and Maxillofacial Surgery, Baldingerstraße, D-35033 Marburg, Germany; E-Mail:
| | - Werner E. G. Müller
- ERC Advanced Investigator Grant Research Group at Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany; E-Mail:
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21
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Inorganic polyphosphates: biologically active biopolymers for biomedical applications. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2013; 54:261-94. [PMID: 24420717 DOI: 10.1007/978-3-642-41004-8_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Inorganic polyphosphate (polyP) is a widely occurring but only rarely investigated biopolymer which exists in both prokaryotic and eukaryotic organisms. Only in the last few years, this polymer has been identified to cause morphogenetic activity on cells involved in human bone formation. The calcium complex of polyP was found to display a dual effect on bone-forming osteoblasts and bone-resorbing osteoclasts. Exposure of these cells to polyP (Ca(2+) complex) elicits the expression of cytokines that promote the mineralization process by osteoblasts and suppress the differentiation of osteoclast precursor cells to the functionally active mature osteoclasts dissolving bone minerals. The effect of polyP on bone formation is associated with an increased release of the bone morphogenetic protein 2 (BMP-2), a key mediator that activates the anabolic processes leading to bone formation. In addition, polyP has been shown to act as a hemostatic regulator that displays various effects on blood coagulation and fibrinolysis and might play an important role in platelet-dependent proinflammatory and procoagulant disorders.
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22
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Vasconcelos ACU, de Azambuja Berti-Couto S, Figueiredo MA, Salum FG, Lopes TG, Cherubini K. Laboratory methods and biomarkers in the evaluation of bisphosphonate effects on body tissues: a literature review. J Oral Pathol Med 2012; 42:577-86. [PMID: 23278676 DOI: 10.1111/jop.12031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2012] [Indexed: 01/06/2023]
Affiliation(s)
- Ana Carolina Uchoa Vasconcelos
- Postgraduate Program; Dental College; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
| | - Soraya de Azambuja Berti-Couto
- Postgraduate Program; Dental College; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
| | - Maria Antonia Figueiredo
- Postgraduate Program; Dental College; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
| | - Fernanda Gonçalves Salum
- Postgraduate Program; Dental College; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
| | - Tiago Giuliani Lopes
- Department of Pathology; School of Medicine; Hospital São Lucas; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
| | - Karen Cherubini
- Postgraduate Program; Dental College; Pontifical Catholic University of Rio Grande do Sul - PUCRS; Porto Alegre RS Brazil
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23
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Longhini R, de Oliveira PA, de Souza Faloni AP, Sasso-Cerri E, Cerri PS. Increased apoptosis in osteoclasts and decreased RANKL immunoexpression in periodontium of cimetidine-treated rats. J Anat 2012. [PMID: 23198931 DOI: 10.1111/joa.12011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
It has been demonstrated that histamine interferes with the recruitment, formation and activity of osteoclasts via H(1)- and H(2)-receptors. Cimetidine is a H(2)-receptor antagonist used for treatment of gastric ulcers that seems to prevent bone resorption. In this study, a possible cimetidine interference was investigated in the number of alveolar bone osteoclasts. The incidence of osteoclast apoptosis and immunoexpression of RANKL (receptor activator of nuclear factor κB ligand) was also evaluated. Adult male rats were treated with 100 mg kg(-1) of cimetidine for 50 days (CimG); the sham group (SG) received saline. Maxillary fragments containing the first molars and alveolar bone were fixed, decalcified and embedded in paraffin. The sections were stained by H&E or submitted to tartrate-resistant acid phosphatase (TRAP) method. TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) method and immunohistochemical reactions for detecting caspase-3 and RANKL were performed. The number of TRAP-positive osteoclasts, the frequency of apoptotic osteoclasts and the numerical density of RANKL-positive cells were obtained. Osteoclast death by apoptosis was confirmed by transmission electron microscopy (TEM). In CimG, TRAP-positive osteoclasts with TUNEL-positive nuclei and caspase-3-immunolabeled osteoclasts were found. A significant reduction in the number of TRAP-positive osteoclasts and a high frequency of apoptotic osteoclasts were observed in CimG. Under TEM, detached osteoclasts from the bone surface showed typical features of apoptosis. Moreover, a significant reduction in the numerical density of RANKL-positive cells was observed in CimG. The significant reduction in the number of osteoclasts may be due to cimetidine-induced osteoclast apoptosis. However, RANKL immunoexpression reduction also suggests a possible interference of cimetidine treatment in the osteoclastogenesis.
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Affiliation(s)
- Renata Longhini
- Federal University of São Paulo, Department of Morphology and Genetics, Brazil
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24
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Harre U, Keppeler H, Ipseiz N, Derer A, Poller K, Aigner M, Schett G, Herrmann M, Lauber K. Moonlighting osteoclasts as undertakers of apoptotic cells. Autoimmunity 2012; 45:612-9. [DOI: 10.3109/08916934.2012.719950] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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25
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Bio-silica and bio-polyphosphate: applications in biomedicine (bone formation). Curr Opin Biotechnol 2012; 23:570-8. [PMID: 22366413 DOI: 10.1016/j.copbio.2012.01.018] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Revised: 01/18/2012] [Accepted: 01/31/2012] [Indexed: 12/31/2022]
Abstract
Bio-silica represents the main mineral component of the sponge skeletal elements (siliceous spicules), while bio-polyphosphate (bio-polyP), a multifunctional polymer existing in microorganisms and animals acts, among others, as reinforcement for pores in cell membranes. These natural inorganic bio-polymers, which can be readily prepared, either by recombinant enzymes (bio-silica and bio-polyP) or chemically (polyP), are promising materials/substances for the amelioration and/or treatment of human bone diseases and dysfunctions. It has been demonstrated that bio-silica causes in vitro a differential effect on the expression of the genes OPG and RANKL, encoding two mediators that control the tuned interaction of the anabolic (osteoblasts) and catabolic (osteoclasts) pathways in human bone cells. Since bio-silica and bio-polyP also induce the expression of the key mediator BMP2 which directs the differentiation of bone-forming progenitor cells to mature osteoblasts and in parallel inhibits the function of osteoclasts, they are promising candidates for treatment of osteoporosis.
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26
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Faloni APDS, Sasso-Cerri E, Rocha FRG, Katchburian E, Cerri PS. Structural and functional changes in the alveolar bone osteoclasts of estrogen-treated rats. J Anat 2011; 220:77-85. [PMID: 22092353 DOI: 10.1111/j.1469-7580.2011.01449.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
This study investigated structural and functional features of apoptotic alveolar bone osteoclasts in estrogen-treated rats. For this purpose, 15 female rats 22 days old were divided into three groups: Estrogen (EG), Sham (SG) and Control (CG). The rats of EG received daily intramuscular injection of estrogen for 7 days. The SG received only the oil vehicle. Maxillary fragments containing alveolar bone were removed and processed for light and transmission electron microscopy. Area (OcA) and number of nuclei (OcN) and bone resorption surface per TRAP-positive osteoclasts (BS/OC) were obtained. Vimentin, caspase-3 and MMP-9 immunoreactions, TUNEL/TRAP and MMP-9/TUNEL combined reactions were performed. In EG, the OcA, OcN and BS/Oc were reduced. Moreover, osteoclasts showed cytoplasm immunolabelled by caspase-3 and a different pattern of vimentin expression in comparison with CG and SG. MMP-9 expression was not affected by estrogen and the TUNEL-positive osteoclasts were MMP-9-immunolabelled. In EG, ultrastructural images showed that apoptotic osteoclasts did not exhibit ruffled borders or clear zones and were shedding mononucleated portions. TRAP-positive structures containing irregular and dense chromatin were partially surrounded by fibroblast-like cells. In conclusion, the reduction in the BS/Oc may be due to reduction in OcA and OcN; these effects seem to be related to vimentin disarrangement rather than to an interference of estrogen with osteoclast MMP-9 expression. Osteoclast apoptosis involves caspase-3 activity and vimentin degradation; these cells release portions containing one apoptotic nucleus and, subsequently, undergo fragmentation, giving rise to apoptotic bodies.
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Fonseca H, Moreira-Gonçalves D, Esteves JLS, Viriato N, Vaz M, Mota MP, Duarte JA. Voluntary exercise has long-term in vivo protective effects on osteocyte viability and bone strength following ovariectomy. Calcif Tissue Int 2011; 88:443-54. [PMID: 21416225 DOI: 10.1007/s00223-011-9476-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 02/25/2011] [Indexed: 12/12/2022]
Abstract
Osteocytes are recognized as having a pivotal role in bone tissue homeostasis, and stimuli that increase osteocyte death result in decreased bone tissue quality. Previous in vitro studies have shown that mechanical stimulation prevents osteocyte death; however, in vivo evidence of this protective effect is limited. The aim of this study was to investigate if mechanical stimulation provided by voluntary exercise reduces osteocyte death caused by estrogen deficiency. Thirty-two female Wistar rats (5 months old) were either sacrificed as baseline controls (BSL, n = 7), ovariectomized or sham-operated and housed in cages with a voluntary running wheel (OVXEX, n = 7; SHAMEX, n = 6), or ovariectomized or sham-operated and housed in standard cages of equivalent size (OVXSED, n = 6; SHAMSED, n = 6) and sacrificed at age 14 months. Histomorphometric analysis of femur mid-diaphysis cortical bone revealed a significantly higher osteocyte number (N.Ot) and lower empty lacunae number (N.Lc) in both the OVXEX and SHAMEX groups compared to their SED counterparts. Intracortical porosity (Po.Ar) was also lower in both EX groups compared to their SED counterparts and significantly correlated with N.Lc (r = 0.616; P < 0.001). Three-point bending testing showed a significantly higher Young's modulus and ultimate stress in OVXEX compared to OVXSED and significant correlations between N.Lc and both yield stress (r = -0.376, P < 0.05) and ultimate stress (r = -0.369, P < 0.05) and between intracortical porosity and bone ultimate stress (r = -0.451, P < 0.05). Our results show that voluntary exercise prevented osteocyte death and that this protective effect was associated with increases in femur ultimate stress, which could be partially explained by decreases in Po.Ar.
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Phosphatidylserine-Containing Liposomes: Potential Pharmacological Interventions Against Inflammatory and Immune Diseases Through the Production of Prostaglandin E2 After Uptake by Myeloid Derived Phagocytes. Arch Immunol Ther Exp (Warsz) 2011; 59:195-201. [DOI: 10.1007/s00005-011-0123-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 11/05/2010] [Indexed: 10/18/2022]
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da Silva GF, Guerreiro-Tanomaru JM, Sasso-Cerri E, Tanomaru-Filho M, Cerri PS. Histological and histomorphometrical evaluation of furcation perforations filled with MTA, CPM and ZOE. Int Endod J 2010; 44:100-10. [DOI: 10.1111/j.1365-2591.2010.01803.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cerri PS, Pereira-Júnior JA, Biselli NB, Sasso-Cerri E. Mast cells and MMP-9 in the lamina propria during eruption of rat molars: quantitative and immunohistochemical evaluation. J Anat 2010; 217:116-25. [PMID: 20557403 DOI: 10.1111/j.1469-7580.2010.01249.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
During the active tooth eruption process, structural changes in the lamina propria are necessary to provide extracellular matrix remodelling and for the establishment of the eruptive pathway. A large number of resident cells, recruited cells and proteases have been demonstrated in the eruptive process, but the participation of MMP-9 and mast cells has not yet been demonstrated. In this study, we set out to evaluate the intensity of MMP-9 immunoexpression, the frequency of mast cells and the correlation between the incidence of mast cells and bone resorption in different phases of tooth eruption. Fragments of maxilla containing first molars, obtained from 9-, 11-, 13- and 16-day-old rats, were fixed in 4% formaldehyde, decalcified and embedded in paraffin. Sagittal sections were stained with Masson's trichrome or submitted to the tartrate-resistant acid phosphatase method for quantification of osteoclasts. Sections stained by 1% toluidine blue were used for quantification of metachromatic mast cells mm(-2) of lamina propria. The expression of MMP-9 in the lamina propria was evaluated by immunohistochemistry. In the 9-day-old rats, the lamina propria contained few mast cells and occasional osteoclasts were found in the bone surface overlying the occlusal portion of the tooth germs. Otherwise, a significant increase in the number of mast cells was observed in the intra-osseous phase of tooth eruption (11-day-old rats), period in which numerous TRAP-positive osteoclasts were found in the bone surface. MMP-9 immunolabelling was detected in fibroblasts, mast cells and macrophage-like cells of the lamina propria in all ages studied. However, an enhanced immunolabelling was evident in the advanced phase of tooth eruption (16-day-old rats). During the intra-osseous phase, the parallel between the high frequency of both mast cells and osteoclasts suggests that mast cells could exert a paracrine function on the osteoclasts and then stimulate bone resorption. The immunoexpression of MMP-9 in different cells of lamina propria, including mast cells, indicates that this enzyme participates in the degradation of ECM, mainly during late phase of mucosal penetration. Thus mast cells and MMP-9 are involved in the complex process of degradation of the eruptive pathway extracellular matrix.
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Affiliation(s)
- Paulo Sérgio Cerri
- Department of Morphology, Laboratory of Histology and Embryology, Dental School, UNESP - Univ. Estadual Paulista, Araraquara, São Paulo, Brazil.
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31
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Wu Z, Ma HM, Kukita T, Nakanishi Y, Nakanishi H. Phosphatidylserine-containing liposomes inhibit the differentiation of osteoclasts and trabecular bone loss. THE JOURNAL OF IMMUNOLOGY 2010; 184:3191-201. [PMID: 20176740 DOI: 10.4049/jimmunol.0803609] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Liposomes containing phosphatidylserine (PS) are engulfed by phagocytes including macrophages, microglia, and dendritic cells. PS liposomes (PSLs) mimic the effects of apoptotic cells on these phagocytes to induce the secretion of anti-inflammatory molecules and to inhibit the maturation of dendritic cells. However, the effects of PSLs on osteoclasts, which are also differentiated from the common myeloid precursors, remain to be determined. This study investigated the effects of PSLs on the osteoclastogenesis. In the rat bone marrow culture system, osteoclast precursors phagocytosed PSLs to secrete TGF-beta1 and PGE(2), which in turn inhibited osteoclastogenesis through the downregulation of receptor activator for NF-kappaB ligand, receptor activator of NF-kappaB, ICAM-1, and CD44. Consistent with these in vitro observations, i.m. injection of PSLs significantly increased the plasma level of TGF-beta1 and PGE(2) and decreased the expression of receptor activator for NF-kappaB ligand, receptor activator of NF-kappaB, and ICAM-1 in the skeletal tissues of ankle joints of rats with adjuvant arthritis (AA). A quantitative analysis using microcomputed tomography revealed that PSLs as well as TGF-beta1 together with PGE(2) significantly inhibited AA-induced trabecular bone loss. These observations strongly suggest that PSLs generate TGF-beta1 and PGE(2) release, leading to inhibit osteoclastogenesis and AA-induced trabecular bone loss. Because PS is a component of the cell membrane, PSLs therefore can be a potentially effective pharmacological intervention against abnormal bone loss, such as osteoporosis without deleterious side effects.
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Affiliation(s)
- Zhou Wu
- Department of Aging Science and Pharmacology, Faculty of Dental Sciences, Kyushu University, Fukuoka, Japan.
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Faloni APS, Sasso-Cerri E, Katchburian E, Cerri PS. Decrease in the number and apoptosis of alveolar bone osteoclasts in estrogen-treated rats. J Periodontal Res 2007; 42:193-201. [PMID: 17451538 DOI: 10.1111/j.1600-0765.2006.00932.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND OBJECTIVE Bone is a mineralized tissue that is under the influence of several systemic, local and environmental factors. Among systemic factors, estrogen is a hormone well known for its inhibitory function on bone resorption. As alveolar bone of young rats undergoes continuous and intense remodeling to accommodate the growing and erupting tooth, it is a suitable in vivo model for using to study the possible action of estrogen on bone. Thus, in an attempt to investigate the possibility that estrogen may induce the death of osteoclasts, we examined the alveolar bone of estrogen-treated rats. MATERIAL AND METHODS Fifteen, 22-d-old female rats were divided into estrogen, sham and control groups. The estrogen group received estrogen and the sham group received corn oil used as the dilution vehicle. After 8 d, fragments containing alveolar bone were removed and processed for light microscopy and transmission electron microscopy. Sections were stained with hematoxylin and eosin and tartrate-resistant acid phosphatase (TRAP)-an osteoclast marker. Quantitative analysis of the number of TRAP-positive osteoclasts per mm of bone surface was carried out. For detecting apoptosis, sections were analyzed by the Terminal deoxynucleotidyl transferase-mediated dUTP Nick-End Labeling (TUNEL) method; TUNEL/TRAP combined methods were also used. RESULTS The number of TRAP-positive osteoclasts per mm of bone surface was significantly reduced in the estrogen group compared with the sham and control groups. TRAP-positive osteoclasts exhibiting TUNEL-positive nuclei were observed only in the estrogen group. In addition, in the estrogen group the ultrastructural images revealed shrunken osteoclasts exhibiting nuclei with conspicuous and tortuous masses of condensed chromatin, typical of apoptosis. CONCLUSION Our results reinforce the idea that estrogen inhibits bone resorption by promoting a reduction in the number of osteoclasts, thus indicating that this reduction may be, at least in part, a consequence of osteoclast apoptosis.
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Affiliation(s)
- A P S Faloni
- Department of Morphology, School of Medicine, Federal University of São Paulo (UNIFESP/EPM), São Paulo, SP, Brazil
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Martin RB. Targeted bone remodeling involves BMU steering as well as activation. Bone 2007; 40:1574-80. [PMID: 17398173 DOI: 10.1016/j.bone.2007.02.023] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 12/26/2006] [Accepted: 02/22/2007] [Indexed: 01/15/2023]
Abstract
Microdamage removal is an important function of bone remodeling. Experiments have repeatedly shown that remodeling of cortical bone by Basic Multicellular Units (BMUs) is initiated in response to microdamage, and this has become known as "targeted remodeling". This paper considers the possibility that microdamage is not only able to activate new BMUs, but may also attract or "steer" existing BMUs as they continue to tunnel through the bone matrix. An initial analysis of the relationship of between mean microcrack length and BMU resorption space density in cortical bone indicates that BMUs have an effective area about 40 times greater than their actual cross-section. Interpreting this as evidence that the osteoclasts in a tunneling BMU are able to sense and steer toward microdamage, a model is developed for "BMU steering" based on the hypothesis that osteoclasts are guided not only in the principal stress direction, as proposed by Burger et al. (Burger, E.H., Klein-Nulend, J., Smit, T.H. Strain-derived canalicular fluid flow regulates osteoclast activity in a remodelling osteon-a proposal. J. Biomech 36 (2003) 1453-1459), but also toward microdamage, depending on its proximity.
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Affiliation(s)
- R B Martin
- Ellison Musculoskeletal Research Center, U.C. Davis Medical Center, Sacramento, CA 95817, USA.
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Effects of hind limb unloading and reloading on nitric oxide synthase expression and apoptosis of osteocytes and chondrocytes. Bone 2006; 39:807-14. [PMID: 16765658 DOI: 10.1016/j.bone.2006.04.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 04/05/2006] [Indexed: 02/07/2023]
Abstract
In rat bone, the absence of mechanical load results in a reduction in bone formation, inhibition of longitudinal growth, and a decrease in the number of osteoblasts and osteoprogenitors in cancellous bone. Unloading has also been linked to an increase in apoptosis of osteocytes and chondrocytes through production of nitric oxide (NO) and increased expression of NO synthases (NOS). Reloading results in recovery of bone volume within 14 days, although osteoblast and osteoclast numbers remain below control values, suggesting decreased bone turnover. This study was designed to evaluate the effects of hind limb unloading and subsequent reloading on apoptosis, NOS expression, and histomorphometric parameters in trabecular and cortical bone, articular cartilage, and growth plate cartilage of the proximal tibia of the hind limbs. Compared to ambulatory controls, 2 weeks of unloading resulted in a 66% increase in the percentage of apoptotic osteocytes in the trabecular metaphysis, a 14% increase in osteoclast number and a 48% decrease in bone volume. The percentage of eNOS- or iNOS-positive osteocytes was unchanged. Upon reloading, the percentage of apoptotic osteocytes and bone volume returned to baseline whereas the percentage of iNOS-positive osteocytes increased by 50% and osteoclast number decreased by 30% compared to ambulatory controls. More striking changes were observed in articular and growth plate cartilage. Unloading resulted in a 230% increase in apoptotic chondrocytes, a 400% increase in iNOS-positive chondrocytes, and a 17% reduction in width in articular cartilage. Reloading for 2 weeks resulted in partial recovery. Chondrocytes in the proliferative and hypertrophic zones of the growth plate responded similarly to those in the articular cartilage. In summary, we observed that 14 days of unloading increased apoptosis of osteocytes and chondrocytes. This was associated with an increase in the proportion of iNOS-positive chondrocytes whereas the proportion of iNOS-positive osteocytes remained unchanged. Reloading for 14 days restored osteocyte apoptosis to control levels but the percentage of iNOS- and eNOS-positive osteocytes increased in reloaded bone compared to controls. This was associated with a decrease in osteoclast number. In cartilage, reloading for 2 weeks did not result in a return to baseline in any of the parameters measured, suggesting that the effects of unloading on articular cartilage and the growth plate last longer than those in bone and may have prolonged effects on joint biomechanics and longitudinal bone growth.
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Cerri PS, Katchburian E. Apoptosis in the epithelial cells of the rests of Malassez of the periodontium of rat molars. J Periodontal Res 2005; 40:365-72. [PMID: 16105088 DOI: 10.1111/j.1600-0765.2005.00810.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVES Epithelial rests of Malassez are clusters of cells derived from Hertwig's root sheath that remain in the periodontal ligament throughout life. Although it is known that the cells of Malassez proliferate, there are no studies showing that they undergo programmed cell death, i.e. apoptosis. In most tissues, proliferation is balanced by apoptosis. Thus we examined regions of the periodontium of young and adult rat molars in the hope of detecting apoptosis. METHODS Wistar rats aged 29, 45 and 120 days were killed with chloral hydrate (600 mg/kg). Fragments containing maxillary molars were removed and fixed in formaldehyde, decalcified, and embedded in paraffin and glycol methacrylate. Sections were stained with hematoxylin/eosin and the Terminal deoxynucleotidyl transferase-mediated dUTP Nick End Labeling (TUNEL) method for detection of apoptosis. Specimens were also fixed in glutaraldehyde-formaldehyde, decalcified and processed for transmission electron microscopy. RESULTS Epithelial rests of Malassez containing round/ovoid basophilic dense bodies and TUNEL-positive structures were found in all specimens examined. Ultrastructural examination revealed that some cells of Malassez contained masses of condensed peripheral chromatin and a shrunken cytoplasm exhibiting intact organelles--images typical of apoptosis. Moreover, round/ovoid electron-opaque structures appeared to be in the process of being engulfed by neighboring epithelial cells of Malassez. CONCLUSIONS Our results demonstrate that epithelial cells of Malassez's rests undergo apoptosis in the developing and adult periodontium. Apoptosis may, together with proliferation, be part of the mechanism of turnover/remodelling of the cells of Malassez.
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Affiliation(s)
- P S Cerri
- Department of Morphology, Dental School, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil.
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Abstract
Cell death has been subdivided into the categories apoptosis (Type I), autophagic cell death (Type II), and necrosis (Type III). The boundary between Type I and II has never been completely clear and perhaps does not exist due to intrinsic factors among different cell types and the crosstalk among organelles within each type. Apoptosis can begin with autophagy, autophagy can end with apoptosis, and blockage of caspase activity can cause a cell to default to Type II cell death from Type I. Furthermore, autophagy is a normal physiological process active in both homeostasis (organelle turnover) and atrophy. "Autophagic cell death" may be interpreted as the process of autophagy that, unlike other situations, does not terminate before the cell collapses. Since switching among the alternative pathways to death is relatively common, interpretations based on knockouts or inhibitors, and therapies directed at controlling apoptosis must include these considerations.
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Affiliation(s)
- Richard A Lockshin
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Jamaica, NY 11439, USA.
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Reaction between Osteoclasts and Osteocytes When They Encounter Each Other at the Bone Resorption Surface during Bone Modeling. J Oral Biosci 2005. [DOI: 10.1016/s1349-0079(05)80026-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Cerri PS. Osteoblasts engulf apoptotic bodies during alveolar bone formation in the rat maxilla. ACTA ACUST UNITED AC 2005; 286:833-40. [PMID: 16047382 DOI: 10.1002/ar.a.20220] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
During bone formation, as in other tissues and organs, intense cellular proliferation and differentiation are usually observed. It has been described that programmed cell death, i.e., apoptosis, takes place in the control of the cellular population by removing of the excessive and damaged cells. Although it is generally accepted that apoptotic bodies are engulfed by professional phagocytes, the neighboring cells can also take part in the removal of apoptotic bodies. In the present study, regions of initial alveolar bone formation of rat molars were examined with the aim to verify whether osteoblasts are capable of engulfing apoptotic bodies, such as professional phagocytes. Rats aged 11-19 days were sacrificed and the maxillary fragments containing the first molar were removed and immersed in the fixative solution. The specimens fixed in glutaraldehyde-formaldehyde were processed for light microscopy and transmission electron microscopy. For the detection of apoptosis, the specimens were fixed in formaldehyde, embedded in paraffin, and submitted to the TUNEL method. The results revealed round/ovoid structures containing dense bodies on the bone surface in close contact to osteoblasts and in conspicuous osteoblast vacuoles. These round/ovoid structures showed also positivity to the TUNEL method, indicating that bone cells on the bone surface are undergoing apoptosis. Ultrathin sections showed images of apoptotic bodies being engulfed by osteoblasts. Occasionally, the osteoblasts exhibited large vacuoles containing blocks of condensed chromatin and remnants of organelles. Thus, these images suggest that osteoblasts are able to engulf and degrade apoptotic bodies.
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Affiliation(s)
- Paulo Sérgio Cerri
- Department of Morphology, Laboratory of Histology and Embryology, Dental School, São Paulo State University, Araraquara, São Paulo, Brazil.
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Mastro AM, Gay CV, Welch DR, Donahue HJ, Jewell J, Mercer R, DiGirolamo D, Chislock EM, Guttridge K. Breast cancer cells induce osteoblast apoptosis: a possible contributor to bone degradation. J Cell Biochem 2004; 91:265-76. [PMID: 14743387 DOI: 10.1002/jcb.10746] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Breast cancer cells exhibit a predilection for metastasis to bone. There, the metastases usually bring about bone loss with accompanying pain and loss of function. One way that breast cancer cells disrupt the normal pattern of bone remodeling is by activating osteoclasts, the bone degrading cells. Nevertheless, targeting the osteoclasts does not cure the disease or result in bone repair. These observations indicate that osteoblast function also may be compromised. The objective of this study was to investigate the interaction of metastatic breast cancer cells with osteoblasts. Human metastatic breast cancer cells, MDA-MB-435 or MDA-MB-231, or their conditioned media were co-cultured with a human osteoblast line hFOB1.19. The breast cancer cells caused an increase in the prevalence of apoptotic osteoblasts. Apoptotic osteoblasts detected by the TUNEL assay or by caspase activity increased approximately two to fivefold. This increase was not seen with non-metastatic MDA-MB-468 cells. In an investigation of the mechanism, it was determined that the hFOB1.19 cells expressed fas and that fas was functional. Likewise the hFOB1.19 cells were susceptible to TNF-alpha, but this cytokine was not detected in the conditioned medium of the breast cancer cells. This study indicates that osteoblasts are the target of breast cancer cell-induced apoptosis, but fas/fas-ligand and TNF-alpha, two common initiators of cell death, are probably not involved in this aspect of the metastases/bone cell axis. There are several mechanisms that remain to be explored in order to determine how breast cancer cells bring about osteoblast apoptosis. Even though the specific initiator of apoptosis remains to be identified, the results of this study suggest that the mechanism is likely to be novel.
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Affiliation(s)
- Andrea M Mastro
- Department of Biochemistry and Molecular Cell Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.
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Abstract
Many cells die with apoptotic morphology and with documented activation of an effector caspase, but there are also many exceptions. Cells frequently display activation of other proteases, including granzymes, lysosomal cathepsins, matrix metalloproteinases, and proteasomal proteases, and others display morphologies that are not fully consistent with classical apoptosis. In some experimental situations, evidence of caspase-dependent death is indirect, demonstrating that the cell can activate caspases rather than that it does. In other situations, such as involution of mammary or prostate tissue, many cells display autophagic or other morphology different from apoptosis, and there is considerable evidence for the activation of a lysosomal system. Prior to total collapse and necrosis, cells that are in trouble can activate numerous physiological pathways toward self-destruction. Intrinsic or extrinsic routes to effector caspase activation are frequently the most rapid and efficient. If neither of these routes is immediately available, owing to mutation, genetic manipulation, inhibitor, or the biology of the cell, other routes may be followed, leading to variant forms of cell death that may display one or more characteristics of apoptosis. Experimental and therapeutic procedures must account for this possibility.
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Affiliation(s)
- Richard A Lockshin
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, USA.
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