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Hansen MS, Madsen K, Price M, Søe K, Omata Y, Zaiss MM, Gorvin CM, Frost M, Rauch A. Transcriptional reprogramming during human osteoclast differentiation identifies regulators of osteoclast activity. Bone Res 2024; 12:5. [PMID: 38263167 PMCID: PMC10806178 DOI: 10.1038/s41413-023-00312-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 11/08/2023] [Accepted: 12/15/2023] [Indexed: 01/25/2024] Open
Abstract
Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis, which is characterized by increased bone resorption and inadequate bone formation. As novel antiosteoporotic therapeutics are needed, understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets. This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation. Osteoclasts were differentiated from CD14+ monocytes from eight female donors. RNA sequencing during differentiation revealed 8 980 differentially expressed genes grouped into eight temporal patterns conserved across donors. These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs. Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks. The donor-specific expression patterns revealed genes at the monocyte stage, such as filamin B (FLNB) and oxidized low-density lipoprotein receptor 1 (OLR1, encoding LOX-1), that are predictive of the resorptive activity of mature osteoclasts. The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation, and these receptors are associated with bone mineral density SNPs, suggesting that they play a pivotal role in osteoclast differentiation and activity. The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1 (C5AR1), somatostatin receptor 2 (SSTR2), and free fatty acid receptor 4 (FFAR4/GPR120). Activating C5AR1 enhanced osteoclast formation, while activating SSTR2 decreased the resorptive activity of mature osteoclasts, and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts. In conclusion, we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity. These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.
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Affiliation(s)
- Morten S Hansen
- Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital, DK-5000, Odense C, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, DK-5000, Odense C, Denmark
- Clinical Cell Biology, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, DK-5000, Odense C, Denmark
| | - Kaja Madsen
- Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital, DK-5000, Odense C, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, DK-5000, Odense C, Denmark
| | - Maria Price
- Institute of Metabolism and Systems Research (IMSR) and Centre for Diabetes, Endocrinology and Metabolism (CEDAM), University of Birmingham, Birmingham, B15 2TT, UK
- Centre for Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Birmingham, B15 2TT, UK
| | - Kent Søe
- Clinical Cell Biology, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, DK-5000, Odense C, Denmark
- Department of Molecular Medicine, University of Southern Denmark, DK-5000, Odense C, Denmark
| | - Yasunori Omata
- Department of Orthopedic Surgery, Faculty of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, D-91054, Erlangen, Germany
| | - Mario M Zaiss
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, D-91054, Erlangen, Germany
- Deutsches Zentrum Immuntherapie (DZI), Friedrich-Alexander-University Erlangen-Nürnberg and Universitätsklinikum Erlangen, D-91054, Erlangen, Germany
| | - Caroline M Gorvin
- Institute of Metabolism and Systems Research (IMSR) and Centre for Diabetes, Endocrinology and Metabolism (CEDAM), University of Birmingham, Birmingham, B15 2TT, UK
- Centre for Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Birmingham, B15 2TT, UK
| | - Morten Frost
- Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital, DK-5000, Odense C, Denmark.
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, DK-5000, Odense C, Denmark.
- Steno Diabetes Center Odense, Odense University Hospital, DK-5000, Odense C, Denmark.
| | - Alexander Rauch
- Molecular Endocrinology Laboratory (KMEB), Department of Endocrinology, Odense University Hospital, DK-5000, Odense C, Denmark.
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, DK-5000, Odense C, Denmark.
- Steno Diabetes Center Odense, Odense University Hospital, DK-5000, Odense C, Denmark.
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Wang Y, Liu H, Zhang Z. Recent Advance in Regulatory Effect of GRP120 on Bone Metabolism. Aging Dis 2023; 14:1714-1727. [PMID: 37196107 PMCID: PMC10529742 DOI: 10.14336/ad.2023.0216] [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: 11/21/2022] [Accepted: 02/16/2023] [Indexed: 05/19/2023] Open
Abstract
The link between fatty acids and bone metabolism is complex and can be direct and indirect. This link has been reported in different types of bone cells and various stages of bone metabolism. G-protein coupled receptor 120 (GPR120), also called free fatty acid receptor 4 (FFAR4), is a member of the recently discovered G protein-coupled receptor family that can interact with both long-chain saturated fatty acids (C14-C18) and long-chain unsaturated fatty acids (C16-C22). Research shows that GPR120 regulates processes in different types of bone cells, directly or indirectly affecting bone metabolism. Our research reviewed the literature on the effects of GPR120 on bone marrow mesenchymal stem cells (BMMSCs), osteoblasts, osteoclasts, and chondrocytes, focusing on the research findings regarding the mechanism by which GPR120 alters specific bone metabolic diseases-osteoporosis and osteoarthritis. The data reviewed here provide a basis for clinical and basic research into the role of GPR120 on bone metabolic diseases.
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Affiliation(s)
| | - Haixia Liu
- Institute of Basic Theory for Chinese Medicine, Chinese Academy of Chinese Medical Sciences, Beijing, China.
| | - Zhiguo Zhang
- Institute of Basic Theory for Chinese Medicine, Chinese Academy of Chinese Medical Sciences, Beijing, China.
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3
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Huang F, Liu X, Fu X, Chen Y, Jiang D, Wang T, Hu R, Zou X, Hu H, Liu C. 3D-Printed Bioactive Scaffold Loaded with GW9508 Promotes Critical-Size Bone Defect Repair by Regulating Intracellular Metabolism. Bioengineering (Basel) 2023; 10:bioengineering10050535. [PMID: 37237605 DOI: 10.3390/bioengineering10050535] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/14/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
The process of bone regeneration is complicated, and it is still a major clinical challenge to regenerate critical-size bone defects caused by severe trauma, infection, and tumor resection. Intracellular metabolism has been found to play an important role in the cell fate decision of skeletal progenitor cells. GW9508, a potent agonist of the free fatty acid receptors GPR40 and GPR120, appears to have a dual effect of inhibiting osteoclastogenesis and promoting osteogenesis by regulating intracellular metabolism. Hence, in this study, GW9508 was loaded on a scaffold based on biomimetic construction principles to facilitate the bone regeneration process. Through 3D printing and ion crosslinking, hybrid inorganic-organic implantation scaffolds were obtained after integrating 3D-printed β-TCP/CaSiO3 scaffolds with a Col/Alg/HA hydrogel. The 3D-printed β-TCP/CaSiO3 scaffolds had an interconnected porous structure that simulated the porous structure and mineral microenvironment of bone, and the hydrogel network shared similar physicochemical properties with the extracellular matrix. The final osteogenic complex was obtained after GW9508 was loaded into the hybrid inorganic-organic scaffold. To investigate the biological effects of the obtained osteogenic complex, in vitro studies and a rat cranial critical-size bone defect model were utilized. Metabolomics analysis was conducted to explore the preliminary mechanism. The results showed that 50 μM GW9508 facilitated osteogenic differentiation by upregulating osteogenic genes, including Alp, Runx2, Osterix, and Spp1 in vitro. The GW9508-loaded osteogenic complex enhanced osteogenic protein secretion and facilitated new bone formation in vivo. Finally, the results from metabolomics analysis suggested that GW9508 promoted stem cell differentiation and bone formation through multiple intracellular metabolism pathways, including purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, and taurine and hypotaurine metabolism. This study provides a new approach to address the challenge of critical-size bone defects.
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Affiliation(s)
- Fangli Huang
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Xiao Liu
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Xihong Fu
- Precision Medicine Institute, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Yan Chen
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Dong Jiang
- Precision Medicine Institute, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Tingxuan Wang
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Rongcheng Hu
- Precision Medicine Institute, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Xuenong Zou
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Hao Hu
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Chun Liu
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
- Precision Medicine Institute, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
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Ma J, Kitaura H, Ogawa S, Ohori F, Noguchi T, Marahleh A, Nara Y, Pramusita A, Kinjo R, Kanou K, Kishikawa A, Ichimura A, Mizoguchi I. Docosahexaenoic acid inhibits TNF-α-induced osteoclast formation and orthodontic tooth movement through GPR120. Front Immunol 2023; 13:929690. [PMID: 36741381 PMCID: PMC9889988 DOI: 10.3389/fimmu.2022.929690] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 12/30/2022] [Indexed: 01/19/2023] Open
Abstract
Docosahexaenoic acid (DHA) is an omega-3 fatty acid that has a range of positive impacts on human health, including anti-inflammatory effects and inhibition of osteoclast formation via G-protein-coupled receptor 120 (GPR120). Orthodontic force was reported to induce tumor necrosis factor-α (TNF-α) expression, which activates osteoclast differentiation during orthodontic tooth movement (OTM). The aim of this study was to investigate the influence of DHA on TNF-α-induced osteoclast formation and OTM in vivo. We examined osteoclast formation and bone resorption within the calvaria of both wild-type (WT) and GPR120-deficient (GPR120-KO) mice injected with phosphate-buffered saline (PBS), TNF-α, TNF-α and DHA, or DHA. DHA inhibited TNF-α-induced osteoclast formation and bone resorption in WT mice but had no effect in GPR120-KO mice. OTM experiments were performed in mouse strains with or without regular injection of DHA, and the effects of DHA on osteoclast formation in the alveolar bones during OTM were examined. DHA also suppressed OTM in WT but not GPR120-KO mice. Our data showed that DHA suppresses TNF-α-induced osteoclastogenesis and bone resorption via GPR120. TNF-α has considerable significance in OTM, and therefore, DHA may also inhibit TNF-α-induced osteoclast formation and bone resorption in OTM.
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Affiliation(s)
- Jinghan Ma
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Hideki Kitaura
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan,*Correspondence: Hideki Kitaura,
| | - Saika Ogawa
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Fumitoshi Ohori
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Takahiro Noguchi
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Aseel Marahleh
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Yasuhiko Nara
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Adya Pramusita
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Ria Kinjo
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Kayoko Kanou
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Akiko Kishikawa
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
| | - Atsuhiko Ichimura
- Department of Biological Chemistry Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Itaru Mizoguchi
- Division of Orthodontics and Dentofacial Orthopedics, Tohoku University Graduate School of Dentistry, Sendai, Miyagi, Japan
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Kim HJ, Lee DK, Jin X, Che X, Ryu SH, Choi JY. Phospholipase D2 controls bone homeostasis by modulating M-CSF-dependent osteoclastic cell migration and microtubule stability. EXPERIMENTAL & MOLECULAR MEDICINE 2022; 54:1146-1155. [PMID: 35945449 PMCID: PMC9440116 DOI: 10.1038/s12276-022-00820-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 05/17/2022] [Accepted: 06/13/2022] [Indexed: 11/09/2022]
Abstract
Phospholipase D2 (PLD2), a signaling protein, plays a central role in cellular communication and various biological processes. Here, we show that PLD2 contributes to bone homeostasis by regulating bone resorption through osteoclastic cell migration and microtubule-dependent cytoskeletal organization. Pld2-deficient mice exhibited a low bone mass attributed to increased osteoclast function without altered osteoblast activity. While Pld2 deficiency did not affect osteoclast differentiation, its absence promoted the migration of osteoclast lineage cells through a mechanism involving M-CSF-induced activation of the PI3K–Akt–GSK3β signaling pathway. The absence of Pld2 also boosted osteoclast spreading and actin ring formation, resulting in elevated bone resorption. Furthermore, Pld2 deletion increased microtubule acetylation and stability, which were later restored by treatment with a specific inhibitor of Akt, an essential molecule for microtubule stabilization and osteoclast bone resorption activity. Interestingly, PLD2 interacted with the M-CSF receptor (c-Fms) and PI3K, and the association between PLD2 and c-Fms was reduced in response to M-CSF. Altogether, our findings indicate that PLD2 regulates bone homeostasis by modulating osteoclastic cell migration and microtubule stability via the M-CSF-dependent PI3K–Akt–GSK3β axis. A signaling protein that regulates bone resorption may prove a useful target in treating skeletal conditions such as osteoporosis and rheumatoid arthritis. Bone is synthesized by cells called osteoblasts, while osteoclasts trigger bone resorption, keeping the skeleton healthy. Imbalances in this recycling process are common in bone disorders. Je-Young Choi and Hyun-Ju Kim at Kyungpook National University in Daegu, South Korea, and co-workers demonstrated that phospholipase D2 (PLD2), a membrane protein, directly regulates bone resorption in mice. Mice without the Pld2 gene had increased osteoclast activity, resulting in low bone mass. The absence of PLD2 promotes the migration of osteoclasts via a particular signaling pathway. This increased the organization of microtubules, polymers that help form the cytoskeleton. The results suggest that regulating PLD2 activity could form the basis of a future treatment method.
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Affiliation(s)
- Hyun-Ju Kim
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu, 41944, Republic of Korea.
| | - Dong-Kyo Lee
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu, 41944, Republic of Korea
| | - Xian Jin
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu, 41944, Republic of Korea
| | - Xiangguo Che
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu, 41944, Republic of Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Je-Yong Choi
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu, 41944, Republic of Korea.
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Hidaka S, Mouri Y, Akiyama M, Miyasaka N, Nakahama KI. GPR110, a receptor for synaptamide, expressed in osteoclasts negatively regulates osteoclastogenesis. Prostaglandins Leukot Essent Fatty Acids 2022; 182:102457. [PMID: 35690003 DOI: 10.1016/j.plefa.2022.102457] [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: 01/11/2022] [Revised: 05/24/2022] [Accepted: 06/02/2022] [Indexed: 12/29/2022]
Abstract
Bone remodeling is precisely regulated mainly by osteoblasts and osteoclasts. Although some G-protein coupled receptors (GPCRs) were reported to play roles in osteoblast function, little is known about the roles in osteoclasts. In this study, we found, for the first time, that the expression of GPR110 increased during osteoclastogenesis. GPR110 belongs to adhesion GPCR and was the functional receptor of N-docosahexaenoyl ethanolamine (also called synaptamide). Synaptamide suppressed osteoclastogenesis induced by receptor activator of nuclear factor-kappa B ligand. Considering that synaptamide is the endogenous metabolite of DHA, we hypothesized that DHA may inhibit osteoclastogenesis by affecting synaptamide/GPR110 signaling. But GPR110 knockout and subsequent rescue experiments revealed a pivotal role of GPR110 in the attenuation of osteoclastogenesis by synaptamide but not by DHA. These results suggest that synaptamide/GPR110 signaling negatively regulates osteoclastogenesis. Our study suggested that ligands of GPR110, such as synaptamide, might be a useful drug for osteoporotic patients.
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Affiliation(s)
- Shiho Hidaka
- Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan; Department of Obstetrics and Gynecology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Yuki Mouri
- Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Masako Akiyama
- Research Administration Division, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
| | - Naoyuki Miyasaka
- Department of Obstetrics and Gynecology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Ken-Ichi Nakahama
- Department of Cellular Physiological Chemistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
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Sithole C, Pieterse C, Howard K, Kasonga A. GPR120 Inhibits RANKL-Induced Osteoclast Formation and Resorption by Attenuating Reactive Oxygen Species Production in RAW264.7 Murine Macrophages. Int J Mol Sci 2021; 22:ijms221910544. [PMID: 34638884 PMCID: PMC8508775 DOI: 10.3390/ijms221910544] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023] Open
Abstract
Osteoclasts are large, multinucleated cells that are responsible for the resorption of bone. Bone degenerative diseases, such as osteoporosis, are characterized by overactive osteoclasts. Receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL) binding to its receptor on osteoclast precursors will trigger osteoclast formation and resorption. The production of reactive oxygen species (ROS) is known to play a crucial role in RANKL-induced osteoclast formation and resorption. G-protein coupled receptor 120 (GPR120) signalling has been shown to affect osteoclast formation, but the exact mechanisms of action require further investigation. RAW264.7 murine macrophages were seeded into culture plates and exposed to the GPR120 agonist, TUG-891, at varying concentrations (20–100 µM) and RANKL to induce osteoclast formation. TUG-891 was shown to inhibit osteoclast formation and resorption without affecting cell viability in RAW264.7 macrophages. TUG-891 further decreased ROS production when compared to RANKL only cells. Antioxidant proteins, Nrf2, HO-1 and NQO1 were shown to be upregulated while the ROS inducing protein, Nox1, was downregulated by TUG-891. Gene silencing revealed that TUG-891 exerted its effects specifically through GPR120. This study reveals that GPR120 signalling may inhibit osteoclast formation and resorption through inhibition on ROS production.
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Affiliation(s)
- Cynthia Sithole
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (C.S.); (C.P.)
| | - Carla Pieterse
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (C.S.); (C.P.)
| | - Kayla Howard
- Division of Clinical Pharmacology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 8000, South Africa;
| | - Abe Kasonga
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa; (C.S.); (C.P.)
- Correspondence: ; Tel.: +27-12-319-2433
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Guo D, Zhao M, Xu W, He H, Li B, Hou T. Dietary interventions for better management of osteoporosis: An overview. Crit Rev Food Sci Nutr 2021; 63:125-144. [PMID: 34251926 DOI: 10.1080/10408398.2021.1944975] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Osteoporosis is a public health concern and a cause of bone loss, increased risk of skeletal fracture, and a heavy economic burden. It is common in postmenopausal women and the elderly and is impacted by dietary factors, lifestyle and some secondary factors. Although many drugs are available for the treatment of osteoporosis, these therapies are accompanied by subsequent side effects. Hence, dietary interventions are highly important to prevent osteoporosis. This review was aimed to provide a comprehensive understanding of the roles of dietary nutrients derived from natural foods and of common dietary patterns in the regulation of osteoporosis. Nutrients from daily diets, such as unsaturated fatty acids, proteins, minerals, peptides, phytoestrogens, and prebiotics, can regulate bone metabolism and reverse bone loss. Meanwhile, these nutrients generally existed in food groups and certain dietary patterns also play critical roles in skeletal health. Appropriate dietary interventions (nutrients and dietary patterns) could be primary and effective strategies to prevent and treat osteoporosis across the lifespan for the consumers and food enterprises.
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Affiliation(s)
- Danjun Guo
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China.,College of Food Science & Engineering, Wuhan Polytechnic University, Wuhan, China
| | - Mengge Zhao
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Wei Xu
- College of Food Science & Engineering, Wuhan Polytechnic University, Wuhan, China
| | - Hui He
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Bin Li
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Tao Hou
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
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Regulation of Osteoclast Differentiation and Activity by Lipid Metabolism. Cells 2021; 10:cells10010089. [PMID: 33430327 PMCID: PMC7825801 DOI: 10.3390/cells10010089] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/02/2021] [Accepted: 01/05/2021] [Indexed: 02/07/2023] Open
Abstract
Bone is a dynamic tissue and is constantly being remodeled by bone cells. Metabolic reprogramming plays a critical role in the activation of these bone cells and skeletal metabolism, which fulfills the energy demand for bone remodeling. Among various metabolic pathways, the importance of lipid metabolism in bone cells has long been appreciated. More recent studies also establish the link between bone loss and lipid-altering conditions—such as atherosclerotic vascular disease, hyperlipidemia, and obesity—and uncover the detrimental effect of fat accumulation on skeletal homeostasis and increased risk of fracture. Targeting lipid metabolism with statin, a lipid-lowering drug, has been shown to improve bone density and quality in metabolic bone diseases. However, the molecular mechanisms of lipid-mediated regulation in osteoclasts are not completely understood. Thus, a better understanding of lipid metabolism in osteoclasts can be used to harness bone cell activity to treat pathological bone disorders. This review summarizes the recent developments of the contribution of lipid metabolism to the function and phenotype of osteoclasts.
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Son SE, Kim NJ, Im DS. Development of Free Fatty Acid Receptor 4 (FFA4/GPR120) Agonists in Health Science. Biomol Ther (Seoul) 2021; 29:22-30. [PMID: 33372166 PMCID: PMC7771848 DOI: 10.4062/biomolther.2020.213] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 11/28/2020] [Accepted: 11/30/2020] [Indexed: 12/14/2022] Open
Abstract
Till the 21st century, fatty acids were considered as merely building blocks for triglycerides, phospholipids, or cholesteryl esters. However, the discovery of G protein-coupled receptors (GPCRs) for free fatty acids at the beginning of the 21st century challenged that idea and paved way for a new field of research, merged into the field of receptor pharmacology for intercellular lipid mediators. Among the GPCRs for free fatty acids, free fatty acid receptor 4 (FFA4, also known as GPR120) recognizes long-chain polyunsaturated fatty acids such as DHA and EPA. It is significant in drug discovery because it regulates obesity-induced metaflammation and GLP-1 secretion. Our study reviews information on newly developed FFA4 agonists and their application in pathophysiologic studies and drug discovery. It also offers a potency comparison of the FFA4 agonists in an AP-TGF-α shedding assay.
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Affiliation(s)
- So-Eun Son
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Nam-Jung Kim
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Dong-Soon Im
- Department of Pharmacy, College of Pharmacy, and Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
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Role of Metabolism in Bone Development and Homeostasis. Int J Mol Sci 2020; 21:ijms21238992. [PMID: 33256181 PMCID: PMC7729585 DOI: 10.3390/ijms21238992] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/22/2020] [Accepted: 11/25/2020] [Indexed: 02/07/2023] Open
Abstract
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies.
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12
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Tsuchiya Y, Hayashi M, Nagamatsu K, Ono T, Kamakura M, Iwata T, Nakashima T. The key royal jelly component 10-hydroxy-2-decenoic acid protects against bone loss by inhibiting NF-κB signaling downstream of FFAR4. J Biol Chem 2020; 295:12224-12232. [PMID: 32647011 PMCID: PMC7443481 DOI: 10.1074/jbc.ra120.013821] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/03/2020] [Indexed: 12/11/2022] Open
Abstract
The supplementation of royal jelly (RJ) is known to provide a variety of health benefits, including anti-inflammatory and anti-obesity effects. RJ treatment also reportedly protects against bone loss, but no single factor in RJ has yet been identified as an anti-osteoporosis agent. Here we fractionated RJ and identified 10-hydroxy-2-decenoic acid (10H2DA) as a key component involved in inhibiting osteoclastogenesis based on mass spectrometric analysis. We further demonstrated free fatty acid receptor 4 (FFAR4) as directly interacting with 10H2DA; binding of 10H2DA to FFAR4 on osteoclasts inhibited receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced activation of NF-κB signaling, thereby attenuating the induction of nuclear factor of activated T cells (NFAT) c1, a key transcription factor for osteoclastogenesis. Oral administration of 10H2DA attenuated bone resorption in ovariectomized mice. These results suggest a potential therapeutic approach of targeting osteoclast differentiation by the supplementation of RJ, and specifically 10H2DA, in cases of pathological bone loss such as occur in postmenopausal osteoporosis.
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Affiliation(s)
- Yosuke Tsuchiya
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Mikihito Hayashi
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Japan Agency for Medical Research and Development, Precursory Research for Innovative Medical Care (PRIME), Tokyo, Japan
| | | | - Takehito Ono
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo, Japan
| | - Masaki Kamakura
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, Toyama, Japan
| | - Takanori Iwata
- Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tomoki Nakashima
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo, Japan.
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13
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Kim HJ, Lee DK, Jin X, Che X, Choi JY. Oleoylethanolamide Exhibits GPR119-Dependent Inhibition of Osteoclast Function and GPR119-Independent Promotion of Osteoclast Apoptosis. Mol Cells 2020; 43:340-349. [PMID: 32050752 PMCID: PMC7191045 DOI: 10.14348/molcells.2020.2260] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 12/20/2022] Open
Abstract
Oleoylethanolamide (OEA), a bioactive lipid in bone, is known as an endogenous ligand for G protein-coupled receptor 119 (GPR119). Here, we explored the effects of OEA on osteoclast differentiation, function, and survival. While OEA inhibits osteoclast resorptive function by disrupting actin cytoskeleton, it does not affect receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. OEA attenuates osteoclast spreading, blocks actin ring formation, and eventually impairs bone resorption. Mechanistically, OEA inhibits Rac activation in response to macrophage colony-stimulating factor (M-CSF), but not RANKL. Furthermore, the OEA-mediated cytoskeletal disorganization is abrogated by GPR119 knockdown using small hairpin RNA (shRNA), indicating that GPR119 is pivotal for osteoclast cytoskeletal organization. In addition, OEA induces apoptosis in both control and GPR119 shRNAtransduced osteoclasts, suggesting that GPR119 is not required for osteoclast apoptosis. Collectively, our findings reveal that OEA has inhibitory effects on osteoclast function and survival of mature osteoclasts via GPR119-dependent and GPR119-independent pathways, respectively.
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Affiliation(s)
- Hyun-Ju Kim
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 PLUS KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Dong-Kyo Lee
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 PLUS KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Xian Jin
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 PLUS KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Xiangguo Che
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 PLUS KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Je-Yong Choi
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, BK21 PLUS KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 41944, Korea
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14
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Barón-Mendoza I, González-Arenas A. Relationship between the effect of polyunsaturated fatty acids (PUFAs) on brain plasticity and the improvement on cognition and behavior in individuals with autism spectrum disorder. Nutr Neurosci 2020; 25:387-410. [PMID: 32338174 DOI: 10.1080/1028415x.2020.1755793] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Objective: This work aimed to compile information about the neuronal processes in which polyunsaturated fatty acids (PUFAs) could modulate brain plasticity, in order to analyze the role of nutritional intervention with the ω-3 and ω-6 fatty acids as a therapeutic strategy for the Autism Spectrum Disorder (ASD)-related signs and symptoms.Methods: We reviewed different articles reporting the effect of PUFAS on neurite elongation, membrane expansion, cytoskeleton rearrangement and neurotransmission, considering the ASD-related abnormalities in these processes.Results: In accordance to the reviewed studies, it is clear that ASD is one of the neurological conditions associated with an impairment in neuronal plasticity; therefore, PUFAs-rich diet improvements on cognition and behavioral deficits in individuals with autism, could be involved with the regulation of neuronal processes implicated in the atypical brain plasticity related with this neurodevelopmental disorder.Discussion: The behavioral and cognitive improvement observed in individuals with ASD after PUFAs treatment might underlie, at least in part, in the ability of ω-3 and ω-6 fatty acids to induce neurite outgrowth, probably, through the dynamic regulation of the neuronal cytoskeleton along with the expansion of neuronal membranes. Furthermore, it might also be associated with an enhancement of the efficacy of synaptic transmission and the modulation of neurotransmitters release.
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Affiliation(s)
- Isabel Barón-Mendoza
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, CDMX, México
| | - Aliesha González-Arenas
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, CDMX, México
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15
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Zhang Y, Wang Z, Xie X, Wang S, Wang Y, Quan G, Wang H, Sun WC. Tatarinan T, an α-asarone-derived lignin, attenuates osteoclastogenesis induced by RANKL via the inhibition of NFATc1/c-Fos expression. Cell Biol Int 2019; 43:1471-1482. [PMID: 31286602 DOI: 10.1002/cbin.11197] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 07/05/2019] [Indexed: 01/24/2023]
Abstract
We have previously reported that the lignin-like compounds, Tatarinan O (TO) and Tatarinan N (TN), extracted from the roots of Acorus tatarinowii Schott, inhibit receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis. In the present study, the potential function of the α-asarone-derived lignins, Tatarinan T (TT) and Tatarinan A (TA), to regulate RANKL-induced osteoclastogenesis was investigated, and it was found that only early treatment with TT may inhibit RANKL-triggered formation of osteoclasts and resorption. The results revealed repressed expression levels of several osteoclast marker genes, including ATPase H+ -transporting V0 subunit d2 (Atp6v0d2), αvβ3 integrin, and osteoclast-associated receptor (OSCAR), following TT treatment during osteoclastogenesis. Moreover, TT reduced the expression levels of the core transcription elements, nuclear factor of activated T-cells cytoplasmic 1 (NFATc1) and c-Fos. However, western blotting analysis showed that TT treatment did not alter nuclear factor-κΒ (NF-κB) activation or mitogen-activated protein kinase (MAPK) or Syk/Btk/phospholipase Cγ2 (PLCγ2) phosphorylation. Taken together, these results suggest the potential of TT in the treatment of diseases of increased bone resorption.
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Affiliation(s)
- Yuxin Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, The Second Hospital of Jilin University, Changchun, 130041, China.,School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China.,Key Laboratory of Molecular Enzymology & Engineering, Ministry of Education, College of Life Science, Jilin University, Changchun, 130021, China
| | - Zhi Wang
- Key Laboratory of Molecular Enzymology & Engineering, Ministry of Education, College of Life Science, Jilin University, Changchun, 130021, China
| | - Xiaona Xie
- The First Hospital of Jilin University, Changchun, 130021, China
| | - Shaoming Wang
- Department of Endocrinology, Changchun People's Hospital, Changchun, 130001, China
| | - Yingjian Wang
- Department of Gynaecology and Obstetrics, China-Japan Union Hospital, Jilin University, Changchun, 130031, China
| | - Guihua Quan
- Key Laboratory of Zoonosis Research, Ministry of Education, The Second Hospital of Jilin University, Changchun, 130041, China
| | - Hongbing Wang
- School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Wan-Chun Sun
- Key Laboratory of Zoonosis Research, Ministry of Education, The Second Hospital of Jilin University, Changchun, 130041, China
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16
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Quach D, Parameswaran N, McCabe L, Britton RA. Characterizing how probiotic Lactobacillus reuteri 6475 and lactobacillic acid mediate suppression of osteoclast differentiation. Bone Rep 2019; 11:100227. [PMID: 31763377 PMCID: PMC6864341 DOI: 10.1016/j.bonr.2019.100227] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 10/07/2019] [Accepted: 10/16/2019] [Indexed: 12/18/2022] Open
Abstract
Osteoporosis is a disease that impacts over 200 million people worldwide. The probiotic bacterium Lactobacillus reuteri (L. reuteri) has been shown to prevent bone loss during estrogen deficiency. Lactobacillic acid is important for L. reuteri-induced suppression of in vitro osteoclastogenesis. Osteoclastogenesis was inhibited by L. reuteri and lactobacillic acid via GPR120 signaling.
Osteoporosis is a disease that impacts over 200 million people worldwide. Taking into consideration the side effects stemming from medications used to treat this illness, investigators have increased their efforts to develop novel therapeutics for osteoporosis. In a previous study, we demonstrated that ovariectomy-induced bone loss in mice was prevented by treatment with the probiotic bacterium Lactobacillus reuteri 6475 (L. reuteri), an effect that correlated with reduced osteoclastogenesis in the bone marrow of L. reuteri treated mice. We also demonstrated that L. reuteri directly inhibited osteoclastogenesis in vitro. To better understand how L. reuteri impacts osteoclast formation, we used additional in vitro analyses to identify that conditioned supernatant from L. reuteri inhibited osteoclastogenesis at the intermediate stage of fused polykaryons. To elucidate the effect of L. reuteri treatment on host cell physiology, we performed RNAseq at multiple time points during in vitro osteoclastogenesis and established that L. reuteri downregulated several KEGG pathways including osteoclast differentiation as well as TNF-α, NF-κB, and MAP kinase signaling. These results were consistent with Western Blot data demonstrating that NF-κB and p38 activation were decreased by L. reuteri treatment. We further identified that lactobacillic acid (LA), a cyclopropane fatty acid produced by L. reuteri, contributed significantly to the suppression of osteoclastogenesis. Additionally, we demonstrated that L. reuteri is signaling through the long chain fatty acid receptor, GPR120, to impact osteoclastogenesis. Overall, these studies provide both bacterial and host mechanisms by which L. reuteri impacts osteoclastogenesis and suggest that long chain fatty acid receptors could be targets for preventing osteoclastogenesis.
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Affiliation(s)
- Darin Quach
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | | | - Laura McCabe
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Robert A. Britton
- Baylor College of Medicine, Department of Molecular Virology and Microbiology, Alkek Center for Metagenomics and Microbiome Research, Houston, TX, USA
- Corresponding author.
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17
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Urso K, Caetano-Lopes J, Lee PY, Yan J, Henke K, Sury M, Liu H, Zgoda M, Jacome-Galarza C, Nigrovic PA, Duryea J, Harris MP, Charles JF. A role for G protein-coupled receptor 137b in bone remodeling in mouse and zebrafish. Bone 2019; 127:104-113. [PMID: 31173907 PMCID: PMC6708790 DOI: 10.1016/j.bone.2019.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/02/2019] [Accepted: 06/03/2019] [Indexed: 12/11/2022]
Abstract
G protein-coupled receptor 137b (GPR137b) is an orphan seven-pass transmembrane receptor of unknown function. In mouse, Gpr137b is highly expressed in osteoclasts in vivo and is upregulated during in vitro differentiation. To elucidate the role that GPR137b plays in osteoclasts, we tested the effect of GPR137b deficiency on osteoclast maturation and resorbing activity. We used CRISPR/Cas9 gene editing in mouse-derived ER-Hoxb8 immortalized myeloid progenitors to generate GPR137b-deficient osteoclast precursors. Decreasing Gpr137b in these precursors led to increased osteoclast differentiation and bone resorption activity. To explore the role of GPR137b during skeletal development, we generated zebrafish deficient for the ortholog gpr137ba. Gpr137ba-deficient zebrafish are viable and fertile and do not display overt morphological defects as adults. However, analysis of osteoclast function in gpr137ba-/- mutants demonstrated increased bone resorption. Micro-computed tomography evaluation of vertebral bone mass and morphology demonstrated that gpr137ba-deficiency altered the angle of the neural arch, a skeletal site with high osteoclast activity. Vital staining of gpr137ba-/- fish with calcein and alizarin red indicated that bone formation in the mutants is also increased, suggesting high bone turnover. These results identify GPR137b as a conserved negative regulator of osteoclast activity essential for normal resorption and patterning of the skeleton. Further, these data suggest that coordination of osteoclast and osteoblast activity is a conserved process among vertebrates and may have similar regulation.
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Affiliation(s)
- K Urso
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - J Caetano-Lopes
- Department of Orthopedic Research, Boston Children's Hospital, Boston, MA, USA; Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - P Y Lee
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Division of Immunology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - J Yan
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - K Henke
- Department of Orthopedic Research, Boston Children's Hospital, Boston, MA, USA; Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - M Sury
- Department of Orthopedic Research, Boston Children's Hospital, Boston, MA, USA; Department of Genetics, Harvard Medical School, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - H Liu
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - M Zgoda
- Department of Orthopedics, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - C Jacome-Galarza
- Department of Orthopedics, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - P A Nigrovic
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Division of Immunology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - J Duryea
- Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - M P Harris
- Department of Orthopedic Research, Boston Children's Hospital, Boston, MA, USA; Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - J F Charles
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Orthopedics, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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18
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Kimura I, Ichimura A, Ohue-Kitano R, Igarashi M. Free Fatty Acid Receptors in Health and Disease. Physiol Rev 2019; 100:171-210. [PMID: 31487233 DOI: 10.1152/physrev.00041.2018] [Citation(s) in RCA: 444] [Impact Index Per Article: 88.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Fatty acids are metabolized and synthesized as energy substrates during biological responses. Long- and medium-chain fatty acids derived mainly from dietary triglycerides, and short-chain fatty acids (SCFAs) produced by gut microbial fermentation of the otherwise indigestible dietary fiber, constitute the major sources of free fatty acids (FFAs) in the metabolic network. Recently, increasing evidence indicates that FFAs serve not only as energy sources but also as natural ligands for a group of orphan G protein-coupled receptors (GPCRs) termed free fatty acid receptors (FFARs), essentially intertwining metabolism and immunity in multiple ways, such as via inflammation regulation and secretion of peptide hormones. To date, several FFARs that are activated by the FFAs of various chain lengths have been identified and characterized. In particular, FFAR1 (GPR40) and FFAR4 (GPR120) are activated by long-chain saturated and unsaturated fatty acids, while FFAR3 (GPR41) and FFAR2 (GPR43) are activated by SCFAs, mainly acetate, butyrate, and propionate. In this review, we discuss the recent reports on the key physiological functions of the FFAR-mediated signaling transduction pathways in the regulation of metabolism and immune responses. We also attempt to reveal future research opportunities for developing therapeutics for metabolic and immune disorders.
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Affiliation(s)
- Ikuo Kimura
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Atsuhiko Ichimura
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Ryuji Ohue-Kitano
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
| | - Miki Igarashi
- Department of Applied Biological Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo, Japan; and Department of Biochemistry, Kyoto University Graduate School of Pharmaceutical Science, Sakyo, Kyoto, Japan
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19
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The role of GPCRs in bone diseases and dysfunctions. Bone Res 2019; 7:19. [PMID: 31646011 PMCID: PMC6804689 DOI: 10.1038/s41413-019-0059-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 05/22/2019] [Accepted: 05/27/2019] [Indexed: 12/13/2022] Open
Abstract
The superfamily of G protein-coupled receptors (GPCRs) contains immense structural and functional diversity and mediates a myriad of biological processes upon activation by various extracellular signals. Critical roles of GPCRs have been established in bone development, remodeling, and disease. Multiple human GPCR mutations impair bone development or metabolism, resulting in osteopathologies. Here we summarize the disease phenotypes and dysfunctions caused by GPCR gene mutations in humans as well as by deletion in animals. To date, 92 receptors (5 glutamate family, 67 rhodopsin family, 5 adhesion, 4 frizzled/taste2 family, 5 secretin family, and 6 other 7TM receptors) have been associated with bone diseases and dysfunctions (36 in humans and 72 in animals). By analyzing data from these 92 GPCRs, we found that mutation or deletion of different individual GPCRs could induce similar bone diseases or dysfunctions, and the same individual GPCR mutation or deletion could induce different bone diseases or dysfunctions in different populations or animal models. Data from human diseases or dysfunctions identified 19 genes whose mutation was associated with human BMD: 9 genes each for human height and osteoporosis; 4 genes each for human osteoarthritis (OA) and fracture risk; and 2 genes each for adolescent idiopathic scoliosis (AIS), periodontitis, osteosarcoma growth, and tooth development. Reports from gene knockout animals found 40 GPCRs whose deficiency reduced bone mass, while deficiency of 22 GPCRs increased bone mass and BMD; deficiency of 8 GPCRs reduced body length, while 5 mice had reduced femur size upon GPCR deletion. Furthermore, deficiency in 6 GPCRs induced osteoporosis; 4 induced osteoarthritis; 3 delayed fracture healing; 3 reduced arthritis severity; and reduced bone strength, increased bone strength, and increased cortical thickness were each observed in 2 GPCR-deficiency models. The ever-expanding number of GPCR mutation-associated diseases warrants accelerated molecular analysis, population studies, and investigation of phenotype correlation with SNPs to elucidate GPCR function in human diseases.
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20
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Kasonga AE, Kruger MC, Coetzee M. Free fatty acid receptor 4-β-arrestin 2 pathway mediates the effects of different classes of unsaturated fatty acids in osteoclasts and osteoblasts. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:281-289. [DOI: 10.1016/j.bbalip.2018.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 12/12/2018] [Accepted: 12/16/2018] [Indexed: 01/28/2023]
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21
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Harasymowicz NS, Dicks A, Wu CL, Guilak F. Physiologic and pathologic effects of dietary free fatty acids on cells of the joint. Ann N Y Acad Sci 2019; 1440:36-53. [PMID: 30648276 DOI: 10.1111/nyas.13999] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/08/2018] [Accepted: 12/14/2018] [Indexed: 12/14/2022]
Abstract
Fatty acids (FAs) are potent organic compounds that not only can be used as an energy source during nutrient deprivation but are also involved in several essential signaling cascades in cells. Therefore, a balanced intake of different dietary FAs is critical for the maintenance of cellular functions and tissue homeostasis. A diet with an imbalanced fat composition creates a risk for developing metabolic syndrome and various musculoskeletal diseases, including osteoarthritis (OA). In this review, we summarize the current state of knowledge and mechanistic insights regarding the role of dietary FAs, such as saturated FAs, omega-6 polyunsaturated FAs (PUFAs), and omega-3 PUFAs on joint inflammation and OA pathogeneses. In particular, we review how different types of dietary FAs and their derivatives distinctly affect a variety of cells within the joint, including chondrocytes, osteoblasts, osteoclasts, and synoviocytes. Understanding the molecular mechanisms underlying the effects of FAs on metabolic behavior, anabolic, and catabolic processes, as well as the inflammatory response of joint cells, may help identify therapeutic targets for the prevention of metabolic joint diseases.
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Affiliation(s)
- Natalia S Harasymowicz
- Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri.,Shriners Hospitals for Children-St. Louis, St. Louis, Missouri
| | - Amanda Dicks
- Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri.,Shriners Hospitals for Children-St. Louis, St. Louis, Missouri.,Department of Biomedical Engineering, Washington University, St. Louis, Missouri
| | - Chia-Lung Wu
- Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri.,Shriners Hospitals for Children-St. Louis, St. Louis, Missouri
| | - Farshid Guilak
- Department of Orthopaedic Surgery, Washington University, St. Louis, Missouri.,Shriners Hospitals for Children-St. Louis, St. Louis, Missouri.,Department of Biomedical Engineering, Washington University, St. Louis, Missouri
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22
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Kishikawa A, Kitaura H, Kimura K, Ogawa S, Qi J, Shen WR, Ohori F, Noguchi T, Marahleh A, Nara Y, Ichimura A, Mizoguchi I. Docosahexaenoic Acid Inhibits Inflammation-Induced Osteoclast Formation and Bone Resorption in vivo Through GPR120 by Inhibiting TNF-α Production in Macrophages and Directly Inhibiting Osteoclast Formation. Front Endocrinol (Lausanne) 2019; 10:157. [PMID: 30949128 PMCID: PMC6436080 DOI: 10.3389/fendo.2019.00157] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 02/22/2019] [Indexed: 02/04/2023] Open
Abstract
Docosahexaenoic acid (DHA) is an n-3 fatty acid that is an important structural component of the cell membrane. DHA exerts potent anti-inflammatory effects through G protein-coupled receptor 120 (GPR120), which is a functional receptor for n-3 fatty acids. DHA also regulates osteoclast formation and function. However, no studies have investigated the effect of DHA on inflammation-induced osteoclast formation in vivo. In the present study, we investigated whether DHA influences osteoclast formation, bone resorption and the expression of osteoclast-associated cytokines during lipopolysaccharide (LPS)-induced inflammation in vivo, and then we elucidated the underlying mechanisms by using in vitro experiments. In vitro experiments revealed both receptor activator of NF-kB ligand (RANKL)- and tumor necrosis factor-α (TNF-α)-induced osteoclast formation was inhibited by DHA. Supracalvarial administration of LPS with or without DHA was carried out for 5 days and then the number of osteoclasts, ratio of bone resorption pits and the level of type I collagen C-terminal cross-linked telopeptide were measured. All measurements were significantly lower in LPS+DHA-co-administered mice than LPS-administered mice. However, this DHA-induced inhibition was not observed in LPS-, DHA-, and selective GPR120 antagonist AH7614-co-administered mice. Furthermore, the expression of RANKL and TNF-α mRNAs was lower in the LPS+DHA-co-administered group than in the LPS-administered group in vivo. TNF-α mRNA levels were decreased in macrophages co-treated with LPS+DHA compared with cells treated with LPS in vitro. In contrast, RANKL mRNA expression levels from osteoblasts co-treated with DHA and LPS in vitro were equal to that in cells treated with LPS alone. Finally, the inhibitory effects of DHA on osteoclast formation in vitro were not observed by using osteoclast precursors from GPR120-deficient mice, and inhibition of LPS-induced osteoclast formation and bone resorption by DHA in vivo was not observed in GPR120-deficient mice. These results suggest that DHA inhibits LPS-induced osteoclast formation and bone resorption in vivo via GPR120 by inhibiting LPS-induced TNF-α production in macrophages along with direct inhibition of osteoclast formation.
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Affiliation(s)
- Akiko Kishikawa
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Hideki Kitaura
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
- *Correspondence: Hideki Kitaura
| | - Keisuke Kimura
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Saika Ogawa
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Jiawei Qi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Wei-Ren Shen
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Fumitoshi Ohori
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Takahiro Noguchi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Aseel Marahleh
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Yasuhiko Nara
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Atsuhiko Ichimura
- Department of Biological Chemistry Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
- Keihanshin Consortium for Fostering the Next Generation of Global Leaders in Research, Kyoto, Japan
| | - Itaru Mizoguchi
- Division of Orthodontics and Dentofacial Orthopedics, Department of Translational Medicine, Tohoku University Graduate School of Dentistry, Sendai, Japan
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Kim H, Yoon H, Park J, Che X, Jin X, Choi J. G protein‐coupled receptor 119 is involved in RANKL‐induced osteoclast differentiation and fusion. J Cell Physiol 2018; 234:11490-11499. [DOI: 10.1002/jcp.27805] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 11/01/2018] [Indexed: 01/08/2023]
Affiliation(s)
- Hyun‐Ju Kim
- Department of Biochemistry and Cell Biology Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Korea
| | - Hye‐Jin Yoon
- Department of Biochemistry and Cell Biology Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Korea
| | - Ji‐Wan Park
- Department of Biomedical Science School of Medicine, Kyungpook National University Daegu Korea
| | - Xiangguo Che
- Department of Biochemistry and Cell Biology Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Korea
| | - Xian Jin
- Department of Biochemistry and Cell Biology Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Korea
| | - Je‐Yong Choi
- Department of Biochemistry and Cell Biology Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Korea
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24
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Kim H, Kim BK, Ohk B, Yoon H, Kang WY, Cho S, Seong SJ, Lee HW, Yoon Y. Estrogen‐related receptor γ negatively regulates osteoclastogenesis and protects against inflammatory bone loss. J Cell Physiol 2018; 234:1659-1670. [DOI: 10.1002/jcp.27035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/25/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Hyun‐Ju Kim
- Department of Molecular Medicine Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Republic of Korea
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Bo Kyung Kim
- Department of Molecular Medicine Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Republic of Korea
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Boram Ohk
- Department of Molecular Medicine Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Republic of Korea
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Hye‐Jin Yoon
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Woo Youl Kang
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Seungil Cho
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Sook Jin Seong
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Hae Won Lee
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
| | - Young‐Ran Yoon
- Department of Molecular Medicine Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University Daegu Republic of Korea
- Clinical Trial Center, Kyungpook National University Hospital Daegu Republic of Korea
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25
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Chen Y, Zhang D, Ho KW, Lin S, Suen WCW, Zhang H, Zha Z, Li G, Leung PS. GPR120 is an important inflammatory regulator in the development of osteoarthritis. Arthritis Res Ther 2018; 20:163. [PMID: 30075737 PMCID: PMC6091098 DOI: 10.1186/s13075-018-1660-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 07/04/2018] [Indexed: 12/28/2022] Open
Abstract
Background The aim of this study was to investigate the regulatory role of G-protein coupled receptor 120 (GPR120) in the development and progression of osteoarthritis (OA). Methods GPR120 knockout (KO) and wild-type (WT) mice were used to create an animal model of OA by means of anterior cruciate ligament transection (ACLT) surgery. The severity of OA was staged and evaluated by histological examination, microcomputed tomography scan and enzyme-linked immunosorbent assay (ELISA). The anti-inflammatory effects of the GPR120 agonist docosahexaenoic acid (DHA) on human chondrocytes were further evaluated by specific inflammatory markers. In addition, the healing progression of a skin defect model was determined with histological assays. Results The GPR120-KO mice displayed an accelerated development of OA after ACLT. The secondary inflammation, cartilage degeneration, and subchondral bone aberrant changes were significantly elevated in the early phase of OA in KO mice relative to those in WT mice. In addition, we found that GPR120 levels were downregulated in OA patients compared with control subjects, whereas GPR120 activation with DHA exhibited anti-inflammatory effects in primary human chondrocytes in vitro. Moreover, results from the skin defect model showed that GPR120 agonism with DHA enhanced wound repair in mice, as shown by the downregulation of the number of CD68+ cells. Conclusions Our study suggests that GPR120 is an important inflammatory mediator during the development of OA, and that it is a potential marker for the diagnosis of high-risk patients with OA. Electronic supplementary material The online version of this article (10.1186/s13075-018-1660-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yuanfeng Chen
- Institute of Orthopedic Diseases and Center for Joint Surgery and Sports Medicine, the First Affiliated Hospital, Jinan University, Guangzhou, People's Republic of China.,Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, People's Republic of China
| | - Dan Zhang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, People's Republic of China
| | - Ki Wai Ho
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China
| | - Sien Lin
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, People's Republic of China
| | - Wade Chun-Wai Suen
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China.,Department of Haematology, University of Cambridge, Cambridge, CB2 0PT, UK
| | - Huantian Zhang
- Institute of Orthopedic Diseases and Center for Joint Surgery and Sports Medicine, the First Affiliated Hospital, Jinan University, Guangzhou, People's Republic of China
| | - Zhengang Zha
- Institute of Orthopedic Diseases and Center for Joint Surgery and Sports Medicine, the First Affiliated Hospital, Jinan University, Guangzhou, People's Republic of China
| | - Gang Li
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, People's Republic of China. .,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, People's Republic of China.
| | - Po Sing Leung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, People's Republic of China.
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26
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ANGPTL2 deletion inhibits osteoclast generation by modulating NF-κB/MAPKs/Cyclin pathways. Biochem Biophys Res Commun 2018; 503:1471-1477. [PMID: 30031603 DOI: 10.1016/j.bbrc.2018.07.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 07/12/2018] [Indexed: 02/05/2023]
Abstract
Osteoclasts are multinucleated cells essential for bone-resorption. Successful repair of bone defciencies still remains a great challenge worldwide. The signaling factor angiopoietin-like protein 2 (ANGPTL2), one of eight ANGPTL proteins, functions in maintenance of tissue homeostasis partly through regulating inflammation. In the study, ANGPTL2 expression was promoted during osteoclast development and that suppressing ANGPTL2 alleviated osteoclast production regulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL). The results suggested that ANGPTL2 knockdown inhibited M-CSF-caused proliferation of osteoclast precursor cells. Further, ANGPTL2 silence reduced nuclear factor of activated T cell c 1 (NFATC1) and NFATC4 expressions in M-CSF-treated cells, along with decreased Runx2, OPN and Colla1. Moreover, silencing ANGPTL2 down-regulated M-CSF-promoted expressions of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and chemoattractant protein-1 (CCL-2). Consistently, ANGPTL2 knockdown reduced M-CSF-enhanced activation of IKKα, IκBα and nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) (p38 MAPK, ERK1/2 MAPK and JNK MAPK). Additionally, knockdown of ANGPTL2 inhibited the induction of Cyclin D1, Cyclin D2 and Cyclin E1 due to M-CSF exposure. In vivo, we confirmed that ANGPTL2 knockout (KO) mice were protected against osteoporosis induced by ovariectomy (OVX), as proved by the improved bone loss and bone mineral density (BMD). Decreased expression of NFATCs was also observed in OVX-induced mice in the absence of ANGPTL2. Elevated release of pro-inflammatory cytokines was abrogated by ANGPTL2 knockout in femoral heads of mice with OVX operation, accompanied with a significant reduction of phosphorylated NF-κB and MAPKs signaling pathways. And down-regulated expression of Cyclin D1, Cyclin D2 and Cyclin E1 was observed in OVX-operated mice with ANGPTL2 knockout. Therefore, our study indicated that ANGPTL2 played an essential role in osteoclast generation through regulating the proliferation and inflammation of osteoclast lineage cells, providing new insights into the therapeutic strategy to alleviate bone loss.
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27
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Senatorov IS, Moniri NH. The role of free-fatty acid receptor-4 (FFA4) in human cancers and cancer cell lines. Biochem Pharmacol 2018; 150:170-180. [PMID: 29452095 DOI: 10.1016/j.bcp.2018.02.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 02/12/2018] [Indexed: 12/12/2022]
Abstract
A dietary influence on cancer progression has been evident for many decades, and dietary fatty acids, particularly long chain mono- and polyunsaturated fatty acids, have been shown to play significant roles in influencing growth of a variety of human cancers. The discovery of the family of cell-surface free-fatty acid receptors, which include the long-chain fatty acid receptors FFA1 and FFA4, suggest that many of the effects of dietary fats could be receptor-mediated. FFA4 is ubiquitously expressed and has recently been shown to modulate a variety of important anti-inflammatory and metabolic processes. Since FFA4 is currently an attractive drug target for treatment of metabolic disorders such as diabetes and obesity, understanding its role in cancer progression is critical towards the drug discovery process. In this research update, the current body of knowledge on the role of this receptor in regulating cancer cell proliferation, migration, and invasion, as well as in vivo tumorigenesis is reviewed.
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Affiliation(s)
- Ilya S Senatorov
- Department of Pharmaceutical Sciences, College of Pharmacy, Mercer University Health Sciences Center, Mercer University, Atlanta, GA 30341, United States
| | - Nader H Moniri
- Department of Pharmaceutical Sciences, College of Pharmacy, Mercer University Health Sciences Center, Mercer University, Atlanta, GA 30341, United States.
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28
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Yeo CE, Kang WY, Seong SJ, Cho S, Lee HW, Yoon YR, Kim HJ. Neuromedin B and its receptor silencing suppresses osteoclast generation by modulating precursor proliferation via M-CSF/c-Fms/D-type cyclins. Exp Cell Res 2017; 359:112-119. [PMID: 28780306 DOI: 10.1016/j.yexcr.2017.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 01/16/2023]
Abstract
Neuromedin B (NMB), a mammalian bombesin-like peptide, regulates diverse physiological processes, such as energy metabolism, memory and fear behavior, and cellular growth, through its cognate receptor, NMBR. In this study, we report that NMB expression was upregulated during osteoclast development and that silencing NMB or NMBR attenuated osteoclast generation mediated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL). We found that knockdown of NMB or NMBR using a small hairpin RNA suppressed M-CSF-induced proliferation of osteoclast precursor cells without altering osteoclast differentiation. Interestingly, NMB or NMBR knockdown reduced the expression of the M-CSF receptor, c-Fms, which is an important modulator of osteoclast development. Consequently, NMB or NMBR silencing inhibited M-CSF/c-Fms-mediated downstream signaling pathways like activation of ERK and Akt and induction of D-type cyclins, cyclin D1 and D2. Moreover, knockdown of NMB or NMBR accelerated apoptosis in osteoclast lineage cells by inducing caspase-3, caspase-9, and Bim expression. In summary, our study demonstrates that the NMB/NMBR axis plays a pivotal role in osteoclast generation by modulating the proliferation and survival of osteoclast lineage cells.
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Affiliation(s)
- Chae-Eun Yeo
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Woo Youl Kang
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Sook Jin Seong
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Seungil Cho
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Hae Won Lee
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Young-Ran Yoon
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea.
| | - Hyun-Ju Kim
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea.
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29
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Park J, Yoon H, Kang WY, Cho S, Seong SJ, Lee HW, Yoon Y, Kim H. G protein‐coupled receptor 84 controls osteoclastogenesis through inhibition of NF‐κB and MAPK signaling pathways. J Cell Physiol 2017; 233:1481-1489. [DOI: 10.1002/jcp.26035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/01/2017] [Indexed: 01/20/2023]
Affiliation(s)
- Ji‐Wan Park
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Hye‐Jin Yoon
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Woo Youl Kang
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Seungil Cho
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Sook Jin Seong
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Hae Won Lee
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Young‐Ran Yoon
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
| | - Hyun‐Ju Kim
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of MedicineKyungpook National University and HospitalDaeguRepublic of Korea
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30
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Hansen SVF, Ulven T. Pharmacological Tool Compounds for the Free Fatty Acid Receptor 4 (FFA4/GPR120). Handb Exp Pharmacol 2017; 236:33-56. [PMID: 27807695 DOI: 10.1007/164_2016_60] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The free fatty acid receptor 4 (FFA4), also known as GPR120, is a G protein-coupled receptor that is activated by long-chain fatty acids and that has been associated with regulation of appetite, release of insulin controlling hormones, insulin sensitization, anti-inflammatory and potentially anti-obesity activity, and is progressively appearing as an attractive potential target for the treatment of metabolic dysfunctions such as obesity, type 2 diabetes and inflammatory disorders. Ongoing investigations of the pharmacological functions of FFA4 and validation of its potential as a therapeutic target depend critically on the appropriateness and quality of the available pharmacological probes or tool compounds. After a brief summary of the pharmacological functions of FFA4 and some general considerations on desirable properties for these pharmacological tool compounds, the individual compounds that have been or are currently being used as tools for probing the function of FFA4 in various in vitro and in vivo settings will be discussed and evaluated.
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Affiliation(s)
- Steffen V F Hansen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Trond Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.
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31
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Milligan G, Shimpukade B, Ulven T, Hudson BD. Complex Pharmacology of Free Fatty Acid Receptors. Chem Rev 2016; 117:67-110. [PMID: 27299848 DOI: 10.1021/acs.chemrev.6b00056] [Citation(s) in RCA: 185] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) are historically the most successful family of drug targets. In recent times it has become clear that the pharmacology of these receptors is far more complex than previously imagined. Understanding of the pharmacological regulation of GPCRs now extends beyond simple competitive agonism or antagonism by ligands interacting with the orthosteric binding site of the receptor to incorporate concepts of allosteric agonism, allosteric modulation, signaling bias, constitutive activity, and inverse agonism. Herein, we consider how evolving concepts of GPCR pharmacology have shaped understanding of the complex pharmacology of receptors that recognize and are activated by nonesterified or "free" fatty acids (FFAs). The FFA family of receptors is a recently deorphanized set of GPCRs, the members of which are now receiving substantial interest as novel targets for the treatment of metabolic and inflammatory diseases. Further understanding of the complex pharmacology of these receptors will be critical to unlocking their ultimate therapeutic potential.
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Affiliation(s)
- Graeme Milligan
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow , Glasgow G12 8QQ, Scotland, United Kingdom
| | - Bharat Shimpukade
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark
| | - Trond Ulven
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark
| | - Brian D Hudson
- Centre for Translational Pharmacology, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow , Glasgow G12 8QQ, Scotland, United Kingdom
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32
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Kim HJ, Kang WY, Seong SJ, Kim SY, Lim MS, Yoon YR. Follistatin-like 1 promotes osteoclast formation via RANKL-mediated NF-κB activation and M-CSF-induced precursor proliferation. Cell Signal 2016; 28:1137-1144. [PMID: 27234130 DOI: 10.1016/j.cellsig.2016.05.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/19/2016] [Accepted: 05/22/2016] [Indexed: 12/25/2022]
Abstract
Follistatin-like 1 (FSTL1) functions as a pivotal modulator of inflammation and is implicated in many inflammatory diseases such as rheumatoid arthritis. Here, we report that FSTL1 is strongly upregulated and secreted during osteoclast differentiation of bone marrow-derived macrophages (BMMs) and that FSTL1 positively regulates osteoclast formation induced by RANKL and M-CSF. The overexpression of FSTL1 or treatment with recombinant FSTL1 (rFSTL1) in BMMs enhances the formation of multinuclear osteoclasts and the induction of c-Fos and NFATc1, transcription factors important for osteoclastogenesis. Conversely, knockdown of FSTL1 using a small hairpin RNA suppresses osteoclast formation and the expression of these transcription factors. While FSTL1 does not affect RANKL-stimulated activation of p38 MAPK, phosphorylation of IκBα, JNK, and ERK were increased by overexpression or addition of rFSTL1. Furthermore, rFSTL1 increased RANKL-induced NF-κB transcriptional activity in a dose-dependent manner. In addition to its role in osteoclastogenesis, FSTL1 promotes proliferation of osteoclast precursors by increasing M-CSF-induced ERK activation, which in turn leads to accelerated osteoclast formation. Together, our findings demonstrate that FSTL1 is a secreted osteoclastogenic factor that plays a critical role in osteoclast formation via the NF-κB and MAPKs signaling pathways.
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Affiliation(s)
- Hyun-Ju Kim
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea; Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 41944, Republic of Korea.
| | - Woo Youl Kang
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Sook Jin Seong
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea
| | - Shin-Yoon Kim
- Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 41944, Republic of Korea
| | - Mi-Sun Lim
- College of Pharmacy, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Young-Ran Yoon
- Department of Biomedical Science, Cell and Matrix Research Institute, BK21 Plus KNU Biomedical Convergence Program, Clinical Trial Center, School of Medicine, Kyungpook National University and Hospital, Daegu 41944, Republic of Korea.
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The Alternative Faces of Macrophage Generate Osteoclasts. BIOMED RESEARCH INTERNATIONAL 2016; 2016:9089610. [PMID: 26977415 PMCID: PMC4761668 DOI: 10.1155/2016/9089610] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/14/2016] [Accepted: 01/18/2016] [Indexed: 01/08/2023]
Abstract
The understanding of how osteoclasts are generated and whether they can be altered by inflammatory stimuli is a topic of particular interest for osteoclastogenesis. It is known that the monocyte/macrophage lineage gives rise to osteoclasts (OCs) by the action of macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-kB ligand (RANKL), which induce cell differentiation through their receptors, c-fms and RANK, respectively. The multinucleated giant cells (MGCs) generated by the engagement of RANK/RANKL are typical OCs. Nevertheless, very few studies have addressed the question of which subset of macrophages generates OCs. Indeed, two main subsets of macrophages are postulated, the inflammatory or classically activated type (M1) and the anti-inflammatory or alternatively activated type (M2). It has been proposed that macrophages can be polarized in vitro towards a predominantly M1 or M2 phenotype with the addition of granulocyte macrophage- (GM-) CSF or M-CSF, respectively. Various inflammatory stimuli known to induce macrophage polarization, such as LPS or TNF-α, can alter the type of MGC obtained from RANKL-induced differentiation. This review aims to highlight the role of immune-related stimuli and factors in inducing macrophages towards the osteoclastogenesis choice.
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Moniri NH. Free-fatty acid receptor-4 (GPR120): Cellular and molecular function and its role in metabolic disorders. Biochem Pharmacol 2016; 110-111:1-15. [PMID: 26827942 DOI: 10.1016/j.bcp.2016.01.021] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/26/2016] [Indexed: 12/12/2022]
Abstract
Over the last decade, a subfamily of G protein-coupled receptors that are agonized by endogenous and dietary free-fatty acids (FFA) has been discovered. These free-fatty acid receptors include FFA2 and FFA3, which are agonized by short-chained FFA, as well as FFA1 and FFA4, which are agonized by medium-to-long chained FFA. Ligands for FFA1 and FFA4 comprise the family of long chain polyunsaturated omega-3 fatty acids including α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), suggesting that many of the long-known beneficial effects of these fats may be receptor mediated. In this regard, FFA4 has gathered considerable interest due to its role in ameliorating inflammation, promoting insulin sensitization, and regulating energy metabolism in response to FFA ligands. The goal of this review is to summarize the body of evidence in regard to FFA4 signal transduction, its mechanisms of regulation, and its functional role in a variety of tissues. In addition, recent endeavors toward discovery of small molecules that modulate FFA4 activity are also presented.
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Affiliation(s)
- Nader H Moniri
- Department of Pharmaceutical Sciences, College of Pharmacy, Mercer University Health Sciences Center, Mercer University, Atlanta, GA 30341, United States.
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