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Wu Z, Guo S, Yue H, Huang H, Zhang Z, Chen X, Lan C, Ren L, Hei P, Wang X, Wang N, Li X. Effect of M2-macrophage treated lymphatic endothelial cells on angiogenesis that promoted osteointegration. Exp Cell Res 2024; 439:114096. [PMID: 38768700 DOI: 10.1016/j.yexcr.2024.114096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/16/2024] [Accepted: 05/18/2024] [Indexed: 05/22/2024]
Abstract
Early vascularization plays an essential role during the whole process in bone regeneration because of the function of secreting cytokines, transporting nutrients and metabolic wastes. As the preliminary basis of bone repair, angiogenesis is regulated by immune cells represented by macrophages to a great extent. However, with the discovery of the endolymphatic circulation system inside bone tissue, the role of vascularization became complicated and confusing. Herein, we developed a macrophage/lymphatic endothelial cells (LECs)/human umbilical vein endothelial cells (HUVECs) co-culture system to evaluate the effect of macrophage treated lymphatic endothelial cells on angiogenesis in vitro and in vivo. In this study, we collected the medium from macrophage (CM) for LECs culture. We found that CM2 could promote the expression of LECs markers and migration ability, which indicated the enhanced lymphogenesis. In addition, the medium from LECs was collected for culturing HUVECs. The CM2-treated LECs showed superior angiogenesis property including the migration capacity and expression of angiogenetic markers, which suggested the superior vascularization. Rat femoral condyle defect model was applied to confirm the hypothesis in vivo. Generally, M2-macrophage treated LECs showed prominent angiogenetic potential coupling with osteogenesis.
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Affiliation(s)
- Zhigang Wu
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China; Department of Orthopaedics, The 63750 Hospital of People's Liberation Army, Xi'an, 710043, Shaanxi, China
| | - Shuo Guo
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, 710032, China; Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Haixia Yue
- Physical Education Department, Xi 'an University of Science and Technology, Xi'an, 710054, China
| | - Hai Huang
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China
| | - Ziru Zhang
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China
| | - Xuexue Chen
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China; Graduate School, Xi'an Physical Education University, Xi'an, 710068, China
| | - Chaoyu Lan
- Graduate School, Xi'an Physical Education University, Xi'an, 710068, China
| | - Lu Ren
- Basic Medical Science Academy, Fourth Military Medical University, Xi'an, 710032, China
| | - Peng Hei
- Graduate School, Xi'an Physical Education University, Xi'an, 710068, China
| | - Xinyu Wang
- Graduate School, Xi'an Physical Education University, Xi'an, 710068, China
| | - Ning Wang
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China.
| | - Xiaokang Li
- Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi, 710038, China.
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Du X, Fan R, Kong J. What improvements do general exercise training and traditional Chinese exercises have on knee osteoarthritis? A narrative review based on biological mechanisms and clinical efficacy. Front Med (Lausanne) 2024; 11:1395375. [PMID: 38841568 PMCID: PMC11150680 DOI: 10.3389/fmed.2024.1395375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Accepted: 04/22/2024] [Indexed: 06/07/2024] Open
Abstract
Background Knee osteoarthritis (KOA) is a disease that significantly affects the quality of life of patients, with a complex pathophysiology that includes degeneration of cartilage and subchondral bone, synovitis, and associations with mechanical load, inflammation, metabolic factors, hormonal changes, and aging. Objective This article aims to comprehensively review the biological mechanisms and clinical effects of general exercise training and traditional Chinese exercises (such as Tai Chi and Qigong) on the treatment of KOA, providing references for the development of clinical exercise prescriptions. Methods A systematic search of databases including PubMed, Web of Science, Google Scholar, and China National Knowledge Infrastructure (CNKI) was conducted, reviewing studies including randomized controlled trials (RCTs), observational studies, systematic reviews, and meta-analyses. Keywords included "knee osteoarthritis," "exercise therapy," "physical activity," and "traditional Chinese exercise." Results and conclusion General exercise training positively affects KOA by mechanisms such as promoting blood circulation, improving the metabolism of inflammatory factors, enhancing the expression of anti-inflammatory cytokines, and reducing cartilage cell aging. Traditional Chinese exercises, like Tai Chi and Qigong, benefit the improvement of KOA symptoms and tissue repair by regulating immune function and alleviating joint inflammation. Clinical studies have shown that both types of exercise can improve physical function, quality of life, and pain relief in patients with KOA. Both general exercise training and traditional Chinese exercises are non-pharmacological treatment options for KOA that can effectively improve patients' physiological function and quality of life. Future research should further explore the long-term effects and biological mechanisms of these exercise interventions and develop personalized exercise programs based on the specific needs of patients.
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Affiliation(s)
- Xingbin Du
- Shandong Huayu University of Technology, Dezhou, China
- Faculty of Education, Qufu Normal University, Qufu, China
| | - Rao Fan
- College of Sports Science, Qufu Normal University, Qufu, China
| | - Jianda Kong
- College of Sports Science, Qufu Normal University, Qufu, China
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Byun KA, Kim HM, Oh S, Batsukh S, Son KH, Byun K. Radiofrequency Treatment Attenuates Age-Related Changes in Dermal-Epidermal Junctions of Animal Skin. Int J Mol Sci 2024; 25:5178. [PMID: 38791217 PMCID: PMC11120932 DOI: 10.3390/ijms25105178] [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: 04/16/2024] [Revised: 05/03/2024] [Accepted: 05/07/2024] [Indexed: 05/26/2024] Open
Abstract
The dermal-epidermal junction (DEJ) is essential for maintaining skin structural integrity and regulating cell survival and proliferation. Thus, DEJ rejuvenation is key for skin revitalization, particularly in age-related DEJ deterioration. Radiofrequency (RF) treatment, known for its ability to enhance collagen fiber production through thermal mechanisms and increase heat shock protein (HSP) expression, has emerged as a promising method for skin rejuvenation. Additionally, RF activates Piezo1, an ion channel implicated in macrophage polarization toward an M2 phenotype and enhanced TGF-β production. This study investigated the impact of RF treatment on HSP47 and HSP90 expression, known stimulators of DEJ protein expression. Furthermore, using in vitro and aged animal skin models, we assessed whether RF-induced Piezo1 activation and the subsequent M2 polarization could counter age-related DEJ changes. The RF treatment of H2O2-induced senescent keratinocytes upregulated the expression of HSP47, HSP90, TGF-β, and DEJ proteins, including collagen XVII. Similarly, the RF treatment of senescent macrophages increased Piezo1 and CD206 (M2 marker) expression. Conditioned media from RF-treated senescent macrophages enhanced the expression of TGF-β and DEJ proteins, such as nidogen and collagen IV, in senescent fibroblasts. In aged animal skin, RF treatment increased the expression of HSP47, HSP90, Piezo1, markers associated with M2 polarization, IL-10, and TGF-β. Additionally, RF treatment enhanced DEJ protein expression. Moreover, RF reduced lamina densa replication, disrupted lesions, promoted hemidesmosome formation, and increased epidermal thickness. Overall, RF treatment effectively enhanced DEJ protein expression and mitigated age-related DEJ structural changes by increasing HSP levels and activating Piezo1.
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Affiliation(s)
- Kyung-A Byun
- Department of Anatomy & Cell Biology, College of Medicine, Gachon University, Incheon 21936, Republic of Korea
- LIBON Inc., Incheon 22006, Republic of Korea
- Functional Cellular Networks Laboratory, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Republic of Korea
| | - Hyoung Moon Kim
- Maylin Anti-Aging Center Ilsan, Goyang 10391, Republic of Korea
| | - Seyeon Oh
- Functional Cellular Networks Laboratory, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Republic of Korea
| | - Sosorburam Batsukh
- Department of Anatomy & Cell Biology, College of Medicine, Gachon University, Incheon 21936, Republic of Korea
- Functional Cellular Networks Laboratory, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Republic of Korea
| | - Kuk Hui Son
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Republic of Korea
| | - Kyunghee Byun
- Department of Anatomy & Cell Biology, College of Medicine, Gachon University, Incheon 21936, Republic of Korea
- Functional Cellular Networks Laboratory, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Republic of Korea
- Department of Health Sciences and Technology, Gachon Advanced Institute for Health & Sciences and Technology (GAIHST), Gachon University, Incheon 21999, Republic of Korea
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Chen Z, Cao Y, Jiang W, Yan Z, Cai G, Ye J, Wang H, Liu L. Porphyromonas gingivalis OMVs promoting endothelial dysfunction via the STING pathway in periodontitis. Oral Dis 2024. [PMID: 38696515 DOI: 10.1111/odi.14969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 04/06/2024] [Accepted: 04/09/2024] [Indexed: 05/04/2024]
Abstract
OBJECTIVE This study aimed to assess the effects of Porphyromonas gingivalis outer membrane vesicles (Pg-OMVs) in chronic periodontitis and explore the underlying mechanism involved. METHODS In vitro, Pg-OMVs were incubated with Ea.hy926 (vessel endothelial cells, ECs) to evaluate their effects on endothelial functions and to investigate the underlying mechanism. The effects of endothelial dysfunction on MG63 osteoblast-like cells were verified using an indirect co-culture method. For in vivo studies, micro-CT was conducted to identify alveolar bone mass. Immunofluorescence staining was conducted to confirm the levels of stimulator of interferon genes (STING) in the blood vessel and the number of Runx2+ cells around the alveolar bone. RESULTS Pg-OMVs were endocytosed by ECs, leading to endothelial dysfunction. The cGAS-STING-TBK1 pathway was activated in ECs, which subsequently inhibited MG63 migration and early osteogenesis differentiation. In vivo, Pg-OMVs promoted alveolar bone resorption, increased STING levels in the blood vessel, and decreased Runx2+ cells around the alveolar bone. CONCLUSIONS Pg-OMVs caused endothelial dysfunction and activated the cGAS-STING-TBK1 signal cascade in ECs, thereby impairing ECs-mediated osteogenesis. Furthermore, Pg-OMVs aggregated alveolar bone loss and altered the blood vessel-mediated osteogenesis with elevated STING.
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Affiliation(s)
- Zhenwei Chen
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Ye Cao
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Wenxiu Jiang
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Zixin Yan
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Guanhui Cai
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Junjie Ye
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
| | - Hua Wang
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
- Department of Orthodontics, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, China
| | - Luwei Liu
- Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, China
- State Key Laboratory Cultivation Base of Research, Prevention and Treatment for Oral Diseases (Nanjing Medical University), Nanjing, China
- Department of Orthodontics, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, China
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Zhang Y, Zou W, Dou W, Luo H, Ouyang X. Pleiotropic physiological functions of Piezo1 in human body and its effect on malignant behavior of tumors. Front Physiol 2024; 15:1377329. [PMID: 38690080 PMCID: PMC11058998 DOI: 10.3389/fphys.2024.1377329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024] Open
Abstract
Mechanosensitive ion channel protein 1 (Piezo1) is a large homotrimeric membrane protein. Piezo1 has various effects and plays an important and irreplaceable role in the maintenance of human life activities and homeostasis of the internal environment. In addition, recent studies have shown that Piezo1 plays a vital role in tumorigenesis, progression, malignancy and clinical prognosis. Piezo1 is involved in regulating the malignant behaviors of a variety of tumors, including cellular metabolic reprogramming, unlimited proliferation, inhibition of apoptosis, maintenance of stemness, angiogenesis, invasion and metastasis. Moreover, Piezo1 regulates tumor progression by affecting the recruitment, activation, and differentiation of multiple immune cells. Therefore, Piezo1 has excellent potential as an anti-tumor target. The article reviews the diverse physiological functions of Piezo1 in the human body and its major cellular pathways during disease development, and describes in detail the specific mechanisms by which Piezo1 affects the malignant behavior of tumors and its recent progress as a new target for tumor therapy, providing new perspectives for exploring more potential effects on physiological functions and its application in tumor therapy.
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Affiliation(s)
- Yihan Zhang
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Jiangxi Medical College, Nanchang University, Nanchang, China
- The Second Clinical Medicine School, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Wen Zou
- The Second Clinical Medicine School, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Wenlei Dou
- The Second Clinical Medicine School, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Hongliang Luo
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Xi Ouyang
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Jiangxi Medical College, Nanchang University, Nanchang, China
- The Second Clinical Medicine School, Jiangxi Medical College, Nanchang University, Nanchang, China
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Liu Z, Luo X, Xu R. Interaction between immuno-stem dual lineages in jaw bone formation and injury repair. Front Cell Dev Biol 2024; 12:1359295. [PMID: 38510177 PMCID: PMC10950953 DOI: 10.3389/fcell.2024.1359295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/26/2024] [Indexed: 03/22/2024] Open
Abstract
The jawbone, a unique structure in the human body, undergoes faster remodeling than other bones due to the presence of stem cells and its distinct immune microenvironment. Long-term exposure of jawbones to an oral environment rich in microbes results in a complex immune balance, as shown by the higher proportion of activated macrophage in the jaw. Stem cells derived from the jawbone have a higher propensity to differentiate into osteoblasts than those derived from other bones. The unique immune microenvironment of the jaw also promotes osteogenic differentiation of jaw stem cells. Here, we summarize the various types of stem cells and immune cells involved in jawbone reconstruction. We describe the mechanism relationship between immune cells and stem cells, including through the production of inflammatory bodies, secretion of cytokines, activation of signaling pathways, etc. In addition, we also comb out cellular interaction of immune cells and stem cells within the jaw under jaw development, homeostasis maintenance and pathological conditions. This review aims to eclucidate the uniqueness of jawbone in the context of stem cell within immune microenvironment, hopefully advancing clinical regeneration of the jawbone.
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Affiliation(s)
| | | | - Ruoshi Xu
- State Key Laboratory of Oral Diseases and National Center for Stomatology and National Clinical Research Center for Oral Diseases and Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Du Y, Xu B, Li Q, Peng C, Yang K. The role of mechanically sensitive ion channel Piezo1 in bone remodeling. Front Bioeng Biotechnol 2024; 12:1342149. [PMID: 38390363 PMCID: PMC10882629 DOI: 10.3389/fbioe.2024.1342149] [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: 11/21/2023] [Accepted: 01/16/2024] [Indexed: 02/24/2024] Open
Abstract
Piezo1 (2010) was identified as a mechanically activated cation channel capable of sensing various physical forces, such as tension, osmotic pressure, and shear force. Piezo1 mediates mechanosensory transduction in different organs and tissues, including its role in maintaining bone homeostasis. This review aimed to summarize the function and possible mechanism of Piezo1 in the mechanical receptor cells in bone tissue. We found that it is a potential therapeutic target for the treatment of bone diseases.
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Affiliation(s)
- Yugui Du
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - Bowen Xu
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - Quiying Li
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - Chuhan Peng
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - Kai Yang
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
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Xiong J, Xiao R, Zhao J, Zhao Q, Luo M, Li F, Zhang W, Wu M. Matrix stiffness affects tumor-associated macrophage functional polarization and its potential in tumor therapy. J Transl Med 2024; 22:85. [PMID: 38246995 PMCID: PMC10800063 DOI: 10.1186/s12967-023-04810-3] [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: 11/08/2023] [Accepted: 12/17/2023] [Indexed: 01/23/2024] Open
Abstract
The extracellular matrix (ECM) plays critical roles in cytoskeletal support, biomechanical transduction and biochemical signal transformation. Tumor-associated macrophage (TAM) function is regulated by matrix stiffness in solid tumors and is often associated with poor prognosis. ECM stiffness-induced mechanical cues can activate cell membrane mechanoreceptors and corresponding mechanotransducers in the cytoplasm, modulating the phenotype of TAMs. Currently, tuning TAM polarization through matrix stiffness-induced mechanical stimulation has received increasing attention, whereas its effect on TAM fate has rarely been summarized. A better understanding of the relationship between matrix stiffness and macrophage function will contribute to the development of new strategies for cancer therapy. In this review, we first introduced the overall relationship between macrophage polarization and matrix stiffness, analyzed the changes in mechanoreceptors and mechanotransducers mediated by matrix stiffness on macrophage function and tumor progression, and finally summarized the effects of targeting ECM stiffness on tumor prognosis to provide insight into this new field.
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Affiliation(s)
- Jiaqiang Xiong
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Rourou Xiao
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Jiahui Zhao
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Qiuyan Zhao
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Manwen Luo
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Feng Li
- Department of Medical Genetics, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China.
- Hubei Provincial Key Laboratory of Allergy and Immunology, Wuhan, 430071, China.
| | - Wei Zhang
- Department of Obstetrics and Gynecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China.
| | - Meng Wu
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430032, China.
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Hu K, Shang Z, Yang X, Zhang Y, Cao L. Macrophage Polarization and the Regulation of Bone Immunity in Bone Homeostasis. J Inflamm Res 2023; 16:3563-3580. [PMID: 37636272 PMCID: PMC10460180 DOI: 10.2147/jir.s423819] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/15/2023] [Indexed: 08/29/2023] Open
Abstract
Bone homeostasis is a dynamic equilibrium state of bone formation and absorption, ensuring skeletal development and repair. Bone immunity encompasses all aspects of the intersection between the skeletal and immune systems, including various signaling pathways, cytokines, and the crosstalk between immune cells and bone cells under both homeostatic and pathological conditions. Therefore, as key cell types in bone immunity, macrophages can polarize into classical pro-inflammatory M1 macrophages and alternative anti-inflammatory M2 macrophages under the influence of the body environment, participating in the regulation of bone metabolism and playing various roles in bone homeostasis. M1 macrophages can not only act as precursors of osteoclasts (OCs), differentiate into mature OCs, but also secrete pro-inflammatory cytokines to promote bone resorption; while M2 macrophages secrete osteogenic factors, stimulating the differentiation and mineralization of osteoblast precursors and mesenchymal stem cells (MSCs), and subsequently increase bone formation. Once the polarization of macrophages is imbalanced, the resulting immune dysregulation will cause inflammatory stimulation, and release a large amount of inflammatory factors affecting bone metabolism, leading to pathological conditions such as osteoporosis (OP), rheumatoid arthritis (RA), and steroid-induced femoral head necrosis (SANFH). In this review, we introduce the signaling pathways and related factors of macrophage polarization, as well as their relationships with immune factors, OB, OC, and MSC. We also discuss the roles of macrophage polarization and bone immunity in various diseases of bone homeostasis imbalance, as well as the factors regulating them, which may help to develop new methods for treating bone metabolic disorders.
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Affiliation(s)
- Kangyi Hu
- Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou, People’s Republic of China
| | - Zhengya Shang
- Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou, People’s Republic of China
| | - Xiaorui Yang
- Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou, People’s Republic of China
| | - Yongjie Zhang
- Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou, People’s Republic of China
| | - Linzhong Cao
- Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou, People’s Republic of China
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