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Schwartzman JD, McCall M, Ghattas Y, Pugazhendhi AS, Wei F, Ngo C, Ruiz J, Seal S, Coathup MJ. Multifunctional scaffolds for bone repair following age-related biological decline: Promising prospects for smart biomaterial-driven technologies. Biomaterials 2024; 311:122683. [PMID: 38954959 DOI: 10.1016/j.biomaterials.2024.122683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/09/2024] [Accepted: 06/23/2024] [Indexed: 07/04/2024]
Abstract
The repair of large bone defects due to trauma, disease, and infection can be exceptionally challenging in the elderly. Despite best clinical practice, bone regeneration within contemporary, surgically implanted synthetic scaffolds is often problematic, inconsistent, and insufficient where additional osteobiological support is required to restore bone. Emergent smart multifunctional biomaterials may drive important and dynamic cellular crosstalk that directly targets, signals, stimulates, and promotes an innate bone repair response following age-related biological decline and when in the presence of disease or infection. However, their role remains largely undetermined. By highlighting their mechanism/s and mode/s of action, this review spotlights smart technologies that favorably align in their conceivable ability to directly target and enhance bone repair and thus are highly promising for future discovery for use in the elderly. The four degrees of interactive scaffold smartness are presented, with a focus on bioactive, bioresponsive, and the yet-to-be-developed autonomous scaffold activity. Further, cell- and biomolecular-assisted approaches were excluded, allowing for contemporary examination of the capabilities, demands, vision, and future requisites of next-generation biomaterial-induced technologies only. Data strongly supports that smart scaffolds hold significant promise in the promotion of bone repair in patients with a reduced osteobiological response. Importantly, many techniques have yet to be tested in preclinical models of aging. Thus, greater clarity on their proficiency to counteract the many unresolved challenges within the scope of aging bone is highly warranted and is arguably the next frontier in the field. This review demonstrates that the use of multifunctional smart synthetic scaffolds with an engineered strategy to circumvent the biological insufficiencies associated with aging bone is a viable route for achieving next-generation therapeutic success in the elderly population.
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Affiliation(s)
| | - Max McCall
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Yasmine Ghattas
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Abinaya Sindu Pugazhendhi
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Fei Wei
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Christopher Ngo
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA
| | - Jonathan Ruiz
- College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Sudipta Seal
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA; Advanced Materials Processing and Analysis Centre, Nanoscience Technology Center (NSTC), Materials Science and Engineering, College of Medicine, University of Central Florida, USA, Orlando, FL
| | - Melanie J Coathup
- College of Medicine, University of Central Florida, Orlando, FL, USA; Biionix Cluster, University of Central Florida, Orlando, FL, USA.
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Lee SY, Kim SJ, Park KH, Lee G, Oh Y, Ryu JH, Huh YH. Differential but complementary roles of HIF-1α and HIF-2α in the regulation of bone homeostasis. Commun Biol 2024; 7:892. [PMID: 39039245 PMCID: PMC11263705 DOI: 10.1038/s42003-024-06581-z] [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: 10/19/2023] [Accepted: 07/11/2024] [Indexed: 07/24/2024] Open
Abstract
Bone is a highly dynamic tissue undergoing continuous formation and resorption. Here, we investigated differential but complementary roles of hypoxia-inducible factor (HIF)-1α and HIF-2α in regulating bone remodeling. Using RNA-seq analysis, we identified that specific genes involved in regulating osteoblast differentiation were similarly but slightly differently governed by HIF-1α and HIF-2α. We found that increased HIF-1α expression inhibited osteoblast differentiation via inhibiting RUNX2 function by upregulation of Twist2, confirmed using Hif1a conditional knockout (KO) mouse. Ectopic expression of HIF-1α via adenovirus transduction resulted in the increased expression and activity of RANKL, while knockdown of Hif1a expression via siRNA or osteoblast-specific depletion of Hif1a in conditional KO mice had no discernible effect on osteoblast-mediated osteoclast activation. The unexpected outcome was elucidated by the upregulation of HIF-2α upon Hif1a overexpression, providing evidence that Hif2a is a transcriptional target of HIF-1α in regulating RANKL expression, verified through an experiment of HIF-2α knockdown after HIF-1α overexpression. The above results were validated in an ovariectomized- and aging-induced osteoporosis model using Hif1a conditional KO mice. Our findings conclude that HIF-1α plays an important role in regulating bone homeostasis by controlling osteoblast differentiation, and in influencing osteoclast formation through the regulation of RANKL secretion via HIF-2α modulation.
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Affiliation(s)
- Sun Young Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Su-Jin Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Ka Hyon Park
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Gyuseok Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Youngsoo Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Je-Hwang Ryu
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.
- Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 61186, Republic of Korea.
| | - Yun Hyun Huh
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
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Wang LL, Lu ZJ, Luo SK, Li Y, Yang Z, Lu HY. Unveiling the role of hypoxia-inducible factor 2alpha in osteoporosis: Implications for bone health. World J Stem Cells 2024; 16:389-409. [PMID: 38690514 PMCID: PMC11056635 DOI: 10.4252/wjsc.v16.i4.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/12/2024] [Accepted: 02/21/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND Osteoporosis (OP) has become a major public health problem worldwide. Most OP treatments are based on the inhibition of bone resorption, and it is necessary to identify additional treatments aimed at enhancing osteogenesis. In the bone marrow (BM) niche, bone mesenchymal stem cells (BMSCs) are exposed to a hypoxic environment. Recently, a few studies have demonstrated that hypoxia-inducible factor 2alpha (HIF-2α) is involved in BMSC osteogenic differentiation, but the molecular mechanism involved has not been determined. AIM To investigate the effect of HIF-2α on the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells (HSCs) in the BM niche on the progression of OP. METHODS Mice with BMSC-specific HIF-2α knockout (Prx1-Cre;Hif-2αfl/fl mice) were used for in vivo experiments. Bone quantification was performed on mice of two genotypes with three interventions: Bilateral ovariectomy, semilethal irradiation, and dexamethasone treatment. Moreover, the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes. In vitro, the HIF-2α agonist roxadustat and the HIF-2α inhibitor PT2399 were used to investigate the function of HIF-2α in BMSC osteogenic and adipogenic differentiation. Finally, we investigated the effect of HIF-2α on BMSCs via treatment with the mechanistic target of rapamycin (mTOR) agonist MHY1485 and the mTOR inhibitor rapamycin. RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions. In vitro, Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2α agonist roxadustat, and after 7 d of BMSC adipogenic differentiation, the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased; in addition, after 14 d of osteogenic differentiation, BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes. The opposite effects were shown for mouse BMSCs treated with the HIF-2α inhibitor PT2399. The mTOR inhibitor rapamycin was used to confirm that HIF-2α regulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway. Consequently, there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice. CONCLUSION Our study showed that inhibition of HIF-2α decreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche.
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Affiliation(s)
- Ling-Ling Wang
- Department of Gerontology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
| | - Zhan-Jin Lu
- Department of Endocrinology and Metabolism, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
| | - Shun-Kui Luo
- Department of Endocrinology and Metabolism, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
| | - Yun Li
- Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
| | - Zhe Yang
- Department of Endocrinology and Metabolism, Zhuhai People's Hospital (Zhuhai Clinical Medical College of Jinan University, the First Hospital Affiliated with Medical College of Macao University of Science and Technology), Zhuhai 519000, Guangdong Province, China
| | - Hong-Yun Lu
- Department of Endocrinology and Metabolism, Zhuhai People's Hospital (Zhuhai Clinical Medical College of Jinan University, the First Hospital Affiliated with Medical College of Macao University of Science and Technology), Zhuhai 519000, Guangdong Province, China.
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Lavu MS, Eghrari NB, Makineni PS, Kaelber DC, Savage JW, Pelle DW. Low-Density Lipoprotein Cholesterol and Statin Usage Are Associated With Rates of Pseudarthrosis Following Single-Level Posterior Lumbar Interbody Fusion. Spine (Phila Pa 1976) 2024; 49:369-377. [PMID: 38073195 DOI: 10.1097/brs.0000000000004895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 11/29/2023] [Indexed: 02/29/2024]
Abstract
STUDY DESIGN Retrospective cohort study. OBJECTIVE To investigate the relationships of low-density lipoprotein cholesterol and statin usage with pseudarthrosis following single-level posterior or transforaminal lumbar interbody fusion (PLIF/TLIF). SUMMARY OF BACKGROUND DATA Hypercholesterolemia can lead to atherosclerosis of the segmental arteries, which branch into vertebral bone through intervertebral foramina. According to the vascular hypothesis of disc disease, this can lead to ischemia of the lumbar discs and contribute to lumbar degenerative disease. Yet, little has been reported regarding the effects of cholesterol and statins on the outcomes of lumbar fusion surgery. MATERIALS AND METHODS TriNetX, a global federated research network, was retrospectively queried to identify 52,140 PLIF/TLIF patients between 2002 and 2021. Of these patients, 2137 had high cholesterol (≥130 mg/dL) and 906 had low cholesterol (≤55 mg/dL). Perioperatively, 18,275 patients used statins, while 33,415 patients did not. One-to-one propensity score matching for age, sex, race, and comorbidities was conducted to balance the analyzed cohorts. The incidence of pseudarthrosis was then assessed in the matched cohorts within the six-month, one-year, and two-year postoperative periods. RESULTS After propensity score matching, high-cholesterol patients had greater odds of developing pseudarthrosis six months [odds ratio (OR): 1.73, 95% confidence interval (CI): 1.28-2.33], one year (OR: 1.59, 95% confidence interval (CI): 1.20-2.10), and two years (OR: 1.57, 95% CI: 1.20-2.05) following a PLIF/TLIF procedure. Patients with statin usage had significantly lower odds of developing pseudarthrosis six months (OR: 0.74, 95% CI: 0.69-0.79), one year (OR: 0.76, 95% CI: 0.71-0.81), and two years (OR: 0.77, 95% CI: 0.72-0.81) following single-level PLIF/TLIF. CONCLUSIONS The findings suggest that patients with hypercholesterolemia have an increased risk of developing pseudarthrosis following PLIF/TLIF while statin use is associated with a decreased risk. The data presented may underscore an overlooked opportunity for perioperative optimization in lumbar fusion patients, warranting further investigation in this area.
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Affiliation(s)
- Monish S Lavu
- Case Western Reserve University School of Medicine, Cleveland, OH
- Center for Spine Health, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH
| | - Nafis B Eghrari
- Case Western Reserve University School of Medicine, Cleveland, OH
- Center for Spine Health, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH
| | - Pratheek S Makineni
- Case Western Reserve University School of Medicine, Cleveland, OH
- Center for Spine Health, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH
| | - David C Kaelber
- Departments of Internal Medicine, Pediatrics, and Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH
- The Center for Clinical Informatics Research and Education, The MetroHealth System, Cleveland, OH
| | - Jason W Savage
- Center for Spine Health, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH
- Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, OH
| | - Dominic W Pelle
- Center for Spine Health, Neurological Institute, Cleveland Clinic Foundation, Cleveland, OH
- Department of Orthopaedic Surgery, Cleveland Clinic Foundation, Cleveland, OH
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Gao Q, Liu J, Wang M, Liu X, Jiang Y, Su J. Biomaterials regulates BMSCs differentiation via mechanical microenvironment. BIOMATERIALS ADVANCES 2024; 157:213738. [PMID: 38154401 DOI: 10.1016/j.bioadv.2023.213738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 12/11/2023] [Accepted: 12/16/2023] [Indexed: 12/30/2023]
Abstract
Bone mesenchymal stem cells (BMSCs) are crucial for bone tissue regeneration, the mechanical microenvironment of hard tissues, including bone and teeth, significantly affects the osteogenic differentiation of BMSCs. Biomaterials may mimic the microenvironment of the extracellular matrix and provide mechanical signals to regulate BMSCs differentiation via inducing the secretion of various intracellular factors. Biomaterials direct the differentiation of BMSCs via mechanical signals, including tension, compression, shear, hydrostatic pressure, stiffness, elasticity, and viscoelasticity, which can be transmitted to cells through mechanical signalling pathways. Besides, biomaterials with piezoelectric effects regulate BMSCs differentiation via indirect mechanical signals, such as, electronic signals, which are transformed from mechanical stimuli by piezoelectric biomaterials. Mechanical stimulation facilitates achieving vectored stem cell fate regulation, while understanding the underlying mechanisms remains challenging. Herein, this review summarizes the intracellular factors, including translation factors, epigenetic modifications, and miRNA level, as well as the extracellular factor, including direct and indirect mechanical signals, which regulate the osteogenic differentiation of BMSCs. Besides, this review will also give a comprehensive summary about how mechanical stimuli regulate cellular behaviours, as well as how biomaterials promote the osteogenic differentiation of BMSCs via mechanical microenvironments. The cellular behaviours and activated signal pathways will give more implications for the design of biomaterials with superior properties for bone tissue engineering. Moreover, it will also provide inspiration for the construction of bone organoids which is a useful tool for mimicking in vivo bone tissue microenvironments.
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Affiliation(s)
- Qianmin Gao
- Institute of Translational Medicine, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; Organoid Research Centre, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; National Centre for Translational Medicine (Shanghai) SHU Branch, NO.333 Nanchen Road, Shanghai University, Shanghai 200444, PR China
| | - Jinlong Liu
- Institute of Translational Medicine, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; Organoid Research Centre, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; National Centre for Translational Medicine (Shanghai) SHU Branch, NO.333 Nanchen Road, Shanghai University, Shanghai 200444, PR China
| | - Mingkai Wang
- Institute of Translational Medicine, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; Organoid Research Centre, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; National Centre for Translational Medicine (Shanghai) SHU Branch, NO.333 Nanchen Road, Shanghai University, Shanghai 200444, PR China
| | - Xiangfei Liu
- Department of Orthopedics, Shanghai Zhongye Hospital, NO. 456 Chunlei Road, Shanghai 200941, PR China.
| | - Yingying Jiang
- Institute of Translational Medicine, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China.
| | - Jiacan Su
- Institute of Translational Medicine, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; Organoid Research Centre, Shanghai University, NO.333 Nanchen Road, Shanghai 200444, PR China; National Centre for Translational Medicine (Shanghai) SHU Branch, NO.333 Nanchen Road, Shanghai University, Shanghai 200444, PR China; Department of Orthopedics, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, NO.1665 Kongjiang Road, Shanghai 200092, PR China.
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Guo W, Hoque J, Garcia CJG, Spiller KV, Leinroth AP, Puviindran V, Potnis CK, Gunn KA, Newman H, Ishikawa K, Fujimoto TN, Neill DW, Delahoussaye AM, Williams NT, Kirsch DG, Hilton MJ, Varghese S, Taniguchi CM, Wu C. Radiation-induced bone loss in mice is ameliorated by inhibition of HIF-2α in skeletal progenitor cells. Sci Transl Med 2023; 15:eabo5217. [PMID: 38019933 PMCID: PMC10804914 DOI: 10.1126/scitranslmed.abo5217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 10/16/2023] [Indexed: 12/01/2023]
Abstract
Radiotherapy remains a common treatment modality for cancer despite skeletal complications. However, there are currently no effective treatments for radiation-induced bone loss, and the consequences of radiotherapy on skeletal progenitor cell (SPC) survival and function remain unclear. After radiation, leptin receptor-expressing cells, which include a population of SPCs, become localized to hypoxic regions of the bone and stabilize the transcription factor hypoxia-inducible factor-2α (HIF-2α), thus suggesting a role for HIF-2α in the skeletal response to radiation. Here, we conditionally knocked out HIF-2α in leptin receptor-expressing cells and their descendants in mice. Radiation therapy in littermate control mice reduced bone mass; however, HIF-2α conditional knockout mice maintained bone mass comparable to nonirradiated control animals. HIF-2α negatively regulated the number of SPCs, bone formation, and bone mineralization. To test whether blocking HIF-2α pharmacologically could reduce bone loss during radiation, we administered a selective HIF-2α inhibitor called PT2399 (a structural analog of which was recently FDA-approved) to wild-type mice before radiation exposure. Pharmacological inhibition of HIF-2α was sufficient to prevent radiation-induced bone loss in a single-limb irradiation mouse model. Given that ~90% of patients who receive a HIF-2α inhibitor develop anemia because of off-target effects, we developed a bone-targeting nanocarrier formulation to deliver the HIF-2α inhibitor to mouse bone, to increase on-target efficacy and reduce off-target toxicities. Nanocarrier-loaded PT2399 prevented radiation-induced bone loss in mice while reducing drug accumulation in the kidney. Targeted inhibition of HIF-2α may represent a therapeutic approach for protecting bone during radiation therapy.
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Affiliation(s)
- Wendi Guo
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine; Durham, NC 27705, USA
| | - Jiaul Hoque
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
| | - Carolina J. Garcia Garcia
- UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
| | - Kassandra V. Spiller
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27705, USA
| | - Abigail P. Leinroth
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Vijitha Puviindran
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
| | - Cahil K. Potnis
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
| | - Kiana A. Gunn
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine; Durham, NC 27705, USA
| | - Hunter Newman
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Mechanical Engineering and Materials Science, Duke University; Durham, NC 27705, USA
| | - Koji Ishikawa
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Orthopaedic Surgery, Showa University School of Medicine, Tokyo, 142-8666, JP
| | - Tara N. Fujimoto
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
| | - Denae W. Neill
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
| | - Abagail M. Delahoussaye
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
| | - Nerissa T. Williams
- Department of Radiation Oncology, Duke University School of Medicine; Durham, NC 27705, USA
| | - David G. Kirsch
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Radiation Oncology, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Biomedical Biophysics, University of Toronto, Toronto, ON, M5S 1A8, CA
- Department of Radiation Oncology, University of Toronto, Toronto, ON, M5T 1O5, CA
- Princess Margarat Cancer Centre, University Health Network, Toronto, ON, M5G 2C1, CA
| | - Matthew J. Hilton
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Cell Biology, Duke University School of Medicine; Durham, NC 27705, USA
| | - Shyni Varghese
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Mechanical Engineering and Materials Science, Duke University; Durham, NC 27705, USA
- Department of Biomedical Engineering, Duke University School of Medicine; Durham, NC 27705, USA
| | - Cullen M. Taniguchi
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
- Department of GI Radiation Oncology, The University of Texas MD Anderson Cancer Center; Houston, TX 77030, USA
| | - Colleen Wu
- Department of Orthopaedic Surgery, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Pharmacology & Cancer Biology, Duke University School of Medicine; Durham, NC 27705, USA
- Department of Radiation Oncology, University of Toronto, Toronto, ON, M5T 1O5, CA
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Imerb N, Thonusin C, Pratchayasakul W, Chanpaisaeng K, Aeimlapa R, Charoenphandhu N, Chattipakorn N, Chattipakorn SC. Hyperbaric oxygen therapy exerts anti-osteoporotic effects in obese and lean D-galactose-induced aged rats. FASEB J 2023; 37:e23262. [PMID: 37855727 DOI: 10.1096/fj.202301197rr] [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: 06/14/2023] [Revised: 09/24/2023] [Accepted: 10/04/2023] [Indexed: 10/20/2023]
Abstract
Obesity accelerates the aging processes, resulting in an aggravation of aging-induced osteoporosis. We investigated the anti-osteoporotic effect of hyperbaric oxygen therapy (HBOT) in obese- and lean-aged rats through measurement of cellular senescence, hypoxia, inflammation, antioxidants, and bone microarchitecture. Obese and lean male Wistar rats were injected with 150 mg/kg/day of D-galactose for 8 weeks to induce aging. Then, all rats were randomly given either sham or HBOT for 14 days. Metabolic parameters were determined. Expression by bone mRNA for cellular senescence, hypoxia, inflammation, antioxidative capacity, and bone remodeling were examined. Micro-computed tomography and atomic absorption spectroscopy were performed to evaluate bone microarchitecture and bone mineral profiles, respectively. We found that HBOT restored the alterations in the mRNA expression level of p16, p21, HIF-1α, TNF-α, IL-6, RANKL, RANK, NFATc1, DC-STAMP, Osx, ALP, and Col1a1 in the bone in obese-and lean- aging rats. In obese-aging rats, HBOT increased the level of expression of Sirt1 and CuZnSOD mRNA and diminished the expression level of HIF-2α and ctsk mRNA to the same levels as the control group. However, HBOT failed to alter catalase and OCN mRNA expression in obese-aged rats. HBOT partially improved the bone microarchitecture in obese-aged rats, but completely restored it in lean-aged rats. Interestingly, HBOT protected against obesity-induced demineralization in obese-aged rats. In summary, HBOT exerts an anti-osteoporotic effect in lean-aged rats and prevents some, but not all the negative effects of obese-aged conditions on bone health. Therefore, HBOT is considered as a potential therapy for aging-induced osteoporosis, regardless of obese status.
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Affiliation(s)
- Napatsorn Imerb
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Chanisa Thonusin
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Wasana Pratchayasakul
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Krittikan Chanpaisaeng
- National Center for Genetic Engineering and Biotechnology (BIOTEC), Pathum Thani, Thailand
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Ratchaneevan Aeimlapa
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Narattaphol Charoenphandhu
- Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand
- The Academy of Science, The Royal Society of Thailand, Bangkok, Thailand
| | - Nipon Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Siriporn C Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
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Wei J, Lin Z, Dai Z, Zhou Z, Bi Y, Zheng R, Hu X, Xu Z, Yuan G, Wang W. Brevilin A inhibits RANKL-induced osteoclast differentiation and bone resorption. In Vitro Cell Dev Biol Anim 2023; 59:420-430. [PMID: 37460875 DOI: 10.1007/s11626-023-00783-1] [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: 03/14/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023]
Abstract
Brevilin A (BA) is the primary component of Centipeda minima, which is widely used in Chinese traditional medicine. The anti-inflammatory and anti-tumor properties of BA have been established; however, its function in bone metabolism is not well understood. This study revealed that concentrations of BA below 1.0 µM did not inhibit the proliferation of bone marrow macrophages but did impede the differentiation and bone resorption activity of osteoclasts. Furthermore, BA suppressed the expression of osteoclast-specific genes Mmp9, Acp5, Dc-stamp, Ctsk, and Atp6v0d2. In addition, mTOR, ERK, and NFATc1 activation in bone marrow macrophages were suppressed by BA. As a whole, BA blocks the mTOR and ERK signaling pathways, which is responsible for the development and activity of osteoclasts, and the resorption of bone.
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Affiliation(s)
- Jinfu Wei
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Zihong Lin
- Department of Shantou Central Hospital, Shantou, 515000, Guangdong, China
| | - Zeyu Dai
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Zibin Zhou
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Yonghao Bi
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Ruiwu Zheng
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Xianghua Hu
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Zhaoxin Xu
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China
| | - Guixin Yuan
- Department of Orthopedics, The Second Affiliated Hospital, Shantou University Medical College, Shantou, 515000, Guangdong, China.
| | - Weidong Wang
- Department of Bone and Soft Tissue Oncology Surgery, Cancer Hospital of Shantou University Medical College, Shantou, 515000, Guangdong, China.
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9
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Pan W, Du J, An L, Xu G, Yuan G, Sheng Y, Sun J, Wang M, Zhao N, Guo X, Li H, Han X. Sika deer velvet antler protein extract modulater bone metabolism and the structure of gut microbiota in ovariectomized mice. Food Sci Nutr 2023; 11:3309-3319. [PMID: 37324858 PMCID: PMC10261755 DOI: 10.1002/fsn3.3316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 02/21/2023] [Accepted: 02/26/2023] [Indexed: 09/20/2023] Open
Abstract
Osteoporosis is a systemic osteopathy characterized by bone metabolism disorders that become more serious with age increases in postmenopausal women. Recent studies have found that antler protein is the main bioactive component of cervus pantotrichum, and it has a positive regulatory effect on bone metabolism and can improve estrogen level. This study aimed to investigate the effect of velvet antler extract (VAE) on the prevention of osteoporosis and the modulation of gut microbiota in ovariectomized (OVX) mice. OVX mice treated with 12 weeks of VAE exhibited higher levels of serum BGP, Ca2+, CT, and HyP (p < .05). Micro-CT scans showed that VAE significantly elevated bone volume fraction (BV/TV), trabecular bone number (Tb.N), trabecular bone thickness (Tb.Th), trabecular bone connection density (Conn.D), decreased trabecular separation (Tb.Sp), and structural modality index (SMI) than untreated OVX mice. The right tibial retinaculum in the VAE group was clearer, with a clearer reticular structure, smaller gaps, a tighter distribution, and a more orderly arrangement. The gut microbiota of the cecal contents was analyzed by 16 s rDNA amplicon sequencing. The data indicated that VAE modulated the species, numbers, and diversity of the gut microbiota in OVX mice. Ovariectomy caused dysbiosis of the intestinal microbiota by increasing the ratio of Firmicutes to Bacteroidetes in mice, but the ratio decreased after treatment with VAE. These results suggest that VAE has a therapeutic effect on OVX mice via modulate bone-related biochemical markers in serum and structure of gut microbiota.
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Affiliation(s)
- Wang Pan
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Juan Du
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Liping An
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Guangyu Xu
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Guangxin Yuan
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Yu Sheng
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Jingbo Sun
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Manli Wang
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Nanxi Zhao
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Xiao Guo
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Hongyu Li
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
| | - Xiao Han
- Department of Pharmaceutical AnalysisBeihua University College of PharmacyJilinChina
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10
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Tsai YL, Wang HP, Wu DW, Huang JC, Wu PY, Chen SC. Low Lung Function Is Associated with Low Baseline Calcaneus Ultrasound T-Score but a Slow Decline in T-Score in a Taiwanese Follow-Up Population with No History of Smoking, Bronchitis, Emphysema, or Asthma. J Pers Med 2023; 13:jpm13050795. [PMID: 37240965 DOI: 10.3390/jpm13050795] [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: 03/23/2023] [Revised: 05/03/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023] Open
Abstract
Osteoporosis is a common disease, and the prevalence is increasing in patients with chronic respiratory diseases, with important implications with regard to fractures, hospitalization, and death. Due to inconsistent data and a lack of large cohort follow-up studies on the association between lung function and osteoporosis, the aim of this study was to investigate this issue. We enrolled and followed for a median of 4 years a total of 9059 participants with no history of smoking, bronchitis, emphysema, or asthma from the Taiwan Biobank. Spirometry data, including forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), were used to assess lung function. Changes in the calcaneus ultrasound T-score (ΔT-score) were calculated as follow-up T-score-baseline T-score. A ΔT-score ≤ -3 (median value of ΔT-score) meant a fast decline in T-score. Multivariable analysis showed that lower values of FEV1 (β, 0.127, p < 0.001), FVC (β, 0.203, p < 0.001), and FEV1/FVC (β, 0.002, p = 0.013) were significantly associated with a low baseline T-score. In addition, after follow-up, higher values of FEV1 (odds ratio (OR), 1.146, p = 0.001), FVC (OR, 1.110, p = 0.042), and FEV1/FVC (OR, 1.004, p = 0.002) were significantly associated with ΔT-score ≤ -3. FEV1/FVC < 70% (OR, 0.838, p < 0.001) was significantly associated with ΔT-score ≤ -3. In conclusion, lower FEV1, FVC, and FEV1/FVC were associated with a low baseline T-score, and higher FEV1, FVC, and FEV1/FVC were associated with a rapid decline in T-score in follow-up. This suggests that lung disease may be associated with bone mineral density in the Taiwanese population with no history of smoking, bronchitis, emphysema, or asthma. Further research is needed to establish causality.
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Affiliation(s)
- Yu-Lin Tsai
- Department of Post Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Hao-Ping Wang
- Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Da-Wei Wu
- Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Jiun-Chi Huang
- Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Pei-Yu Wu
- Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Szu-Chia Chen
- Department of Internal Medicine, Kaohsiung Municipal Siaogang Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Research Center for Precision Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
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11
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Yang J, Li Q, Feng Y, Zeng Y. Iron Deficiency and Iron Deficiency Anemia: Potential Risk Factors in Bone Loss. Int J Mol Sci 2023; 24:ijms24086891. [PMID: 37108056 PMCID: PMC10138976 DOI: 10.3390/ijms24086891] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/01/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
Iron is one of the essential mineral elements for the human body and this nutrient deficiency is a worldwide public health problem. Iron is essential in oxygen transport, participates in many enzyme systems in the body, and is an important trace element in maintaining basic cellular life activities. Iron also plays an important role in collagen synthesis and vitamin D metabolism. Therefore, decrease in intracellular iron can lead to disturbance in the activity and function of osteoblasts and osteoclasts, resulting in imbalance in bone homeostasis and ultimately bone loss. Indeed, iron deficiency, with or without anemia, leads to osteopenia or osteoporosis, which has been revealed by numerous clinical observations and animal studies. This review presents current knowledge on iron metabolism under iron deficiency states and the diagnosis and prevention of iron deficiency and iron deficiency anemia (IDA). With emphasis, studies related to iron deficiency and bone loss are discussed, and the potential mechanisms of iron deficiency leading to bone loss are analyzed. Finally, several measures to promote complete recovery and prevention of iron deficiency are listed to improve quality of life, including bone health.
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Affiliation(s)
- Jiancheng Yang
- Department of Osteoporosis, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Qingmei Li
- Department of Osteoporosis, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Yan Feng
- Department of Osteoporosis, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Yuhong Zeng
- Department of Osteoporosis, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
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12
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Mendoza SV, Genetos DC, Yellowley CE. Hypoxia-Inducible Factor-2α Signaling in the Skeletal System. JBMR Plus 2023; 7:e10733. [PMID: 37065626 PMCID: PMC10097641 DOI: 10.1002/jbm4.10733] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/23/2023] [Accepted: 01/29/2023] [Indexed: 02/13/2023] Open
Abstract
Hypoxia-inducible factors (HIFs) are oxygen-dependent heterodimeric transcription factors that mediate molecular responses to reductions in cellular oxygen (hypoxia). HIF signaling involves stable HIF-β subunits and labile, oxygen-sensitive HIF-α subunits. Under hypoxic conditions, the HIF-α subunit is stabilized, complexes with nucleus-confined HIF-β subunit, and transcriptionally regulates hypoxia-adaptive genes. Transcriptional responses to hypoxia include altered energy metabolism, angiogenesis, erythropoiesis, and cell fate. Three isoforms of HIF-α-HIF-1α, HIF-2α, and HIF-3α-are found in diverse cell types. HIF-1α and HIF-2α serve as transcriptional activators, whereas HIF-3α restricts HIF-1α and HIF-2α. The structure and isoform-specific functions of HIF-1α in mediating molecular responses to hypoxia are well established across a wide range of cell and tissue types. The contributions of HIF-2α to hypoxic adaptation are often unconsidered if not outrightly attributed to HIF-1α. This review establishes what is currently known about the diverse roles of HIF-2α in mediating the hypoxic response in skeletal tissues, with specific focus on development and maintenance of skeletal fitness. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Sarah V Mendoza
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California, DavisDavisCAUSA
| | - Damian C Genetos
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California, DavisDavisCAUSA
| | - Clare E Yellowley
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California, DavisDavisCAUSA
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13
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Mendoza SV, Murugesh DK, Christiansen BA, Genetos ZO, Loots GG, Genetos DC, Yellowley CE. Degradation-Resistant Hypoxia Inducible Factor-2α in Murine Osteocytes Promotes a High Bone Mass Phenotype. JBMR Plus 2023; 7:e10724. [PMID: 37065633 PMCID: PMC10097640 DOI: 10.1002/jbm4.10724] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/22/2022] [Accepted: 01/18/2023] [Indexed: 01/26/2023] Open
Abstract
Molecular oxygen levels vary during development and disease. Adaptations to decreased oxygen bioavailability (hypoxia) are mediated by hypoxia-inducible factor (HIF) transcription factors. HIFs are composed of an oxygen-dependent α subunit (HIF-α), of which there are two transcriptionally active isoforms (HIF-1α and HIF-2α), and a constitutively expressed β subunit (HIFβ). Under normoxic conditions, HIF-α is hydroxylated via prolyl hydroxylase domain (PHD) proteins and targeted for degradation via Von Hippel-Lindau (VHL). Under hypoxic conditions, hydroxylation via PHD is inhibited, allowing for HIF-α stabilization and induction of target transcriptional changes. Our previous studies showed that Vhl deletion in osteocytes (Dmp1-cre; Vhl f/f ) resulted in HIF-α stabilization and generation of a high bone mass (HBM) phenotype. The skeletal impact of HIF-1α accumulation has been well characterized; however, the unique skeletal impacts of HIF-2α remain understudied. Because osteocytes orchestrate skeletal development and homeostasis, we investigated the role of osteocytic HIF-α isoforms in driving HBM phenotypes via osteocyte-specific loss-of-function and gain-of-function HIF-1α and HIF-2α mutations in C57BL/6 female mice. Deletion of Hif1a or Hif2a in osteocytes showed no effect on skeletal microarchitecture. Constitutively stable, degradation-resistant HIF-2α (HIF-2α cDR), but not HIF-1α cDR, generated dramatic increases in bone mass, enhanced osteoclast activity, and expansion of metaphyseal marrow stromal tissue at the expense of hematopoietic tissue. Our studies reveal a novel influence of osteocytic HIF-2α in driving HBM phenotypes that can potentially be harnessed pharmacologically to improve bone mass and reduce fracture risk. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Sarah V. Mendoza
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California DavisDavisCAUSA
| | - Deepa K. Murugesh
- Lawrence Livermore National LaboratoriesPhysical and Life Sciences DirectorateLivermoreCAUSA
| | | | - Zoe O. Genetos
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California DavisDavisCAUSA
| | - Gabriela G. Loots
- Lawrence Livermore National LaboratoriesPhysical and Life Sciences DirectorateLivermoreCAUSA
| | - Damian C. Genetos
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California DavisDavisCAUSA
| | - Clare E. Yellowley
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary MedicineUniversity of California DavisDavisCAUSA
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14
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Xing W, Larkin D, Pourteymoor S, Tambunan W, Gomez GA, Liu EK, Mohan S. Lack of Skeletal Effects in Mice with Targeted Disruptionof Prolyl Hydroxylase Domain 1 ( Phd1) Gene Expressed in Chondrocytes. Life (Basel) 2022; 13:106. [PMID: 36676055 PMCID: PMC9862499 DOI: 10.3390/life13010106] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/16/2022] [Accepted: 12/28/2022] [Indexed: 01/01/2023] Open
Abstract
The critical importance of hypoxia-inducible factor (HIF)s in the regulation of endochondral bone formation is now well established. HIF protein levels are closely regulated by the prolyl hydroxylase domain-containing protein (PHD) mediated ubiquitin-proteasomal degradation pathway. Of the three PHD family members expressed in bone, we previously showed that mice with conditional disruption of the Phd2 gene in chondrocytes led to a massive increase in the trabecular bone mass of the long bones. By contrast, loss of Phd3 expression in chondrocytes had no skeletal effects. To investigate the role of Phd1 expressed in chondrocytes on skeletal development, we conditionally disrupted the Phd1 gene in chondrocytes by crossing Phd1 floxed mice with Collagen 2α1-Cre mice for evaluation of a skeletal phenotype. At 12 weeks of age, neither body weight nor body length was significantly different in the Cre+; Phd1flox/flox conditional knockout (cKO) mice compared to Cre−; Phd1flox/flox wild-type (WT) control mice. Micro-CT measurements revealed significant gender differences in the trabecular bone volume adjusted for tissue volume at the secondary spongiosa of the femur and the tibia for both genotypes, but no genotype differences were found for any of the trabecular bone measurements of either femur or tibia. Similarly, cortical bone parameters were not affected in the Phd1 cKO mice compared to control mice. Histomorphometric analyses revealed no significant differences in bone area, bone formation rate or mineral apposition rate in the secondary spongiosa of femurs between cKO and WT control mice. Loss of Phd1 expression in chondrocytes did not affect the expression of markers of chondrocytes (collage 2, collagen 10) or osteoblasts (alkaline phosphatase, bone sialoprotein) in the bones of cKO mice. Based on these and our published data, we conclude that of the three PHD family members, only Phd2 expressed in chondrocytes regulates endochondral bone formation and development of peak bone mass in mice.
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Affiliation(s)
- Weirong Xing
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
- Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
| | - Destiney Larkin
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
| | - Sheila Pourteymoor
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
| | - William Tambunan
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
| | - Gustavo A. Gomez
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
| | - Elaine K. Liu
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA
- Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
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15
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Srivastava RK, Sapra L, Mishra PK. Osteometabolism: Metabolic Alterations in Bone Pathologies. Cells 2022; 11:3943. [PMID: 36497201 PMCID: PMC9735555 DOI: 10.3390/cells11233943] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/20/2022] [Accepted: 11/24/2022] [Indexed: 12/12/2022] Open
Abstract
Renewing interest in the study of intermediate metabolism and cellular bioenergetics is brought on by the global increase in the prevalence of metabolic illnesses. Understanding of the mechanisms that integrate energy metabolism in the entire organism has significantly improved with the application of contemporary biochemical tools for quantifying the fuel substrate metabolism with cutting-edge mouse genetic procedures. Several unexpected findings in genetically altered mice have prompted research into the direction of intermediate metabolism of skeletal cells. These findings point to the possibility of novel endocrine connections through which bone cells can convey their energy status to other metabolic control centers. Understanding the expanded function of skeleton system has in turn inspired new lines of research aimed at characterizing the energy needs and bioenergetic characteristics of these bone cells. Bone-forming osteoblast and bone-resorbing osteoclast cells require a constant and large supply of energy substrates such as glucose, fatty acids, glutamine, etc., for their differentiation and functional activity. According to latest research, important developmental signaling pathways in bone cells are connected to bioenergetic programs, which may accommodate variations in energy requirements during their life cycle. The present review article provides a unique perspective of the past and present research in the metabolic characteristics of bone cells along with mechanisms governing energy substrate utilization and bioenergetics. In addition, we discussed the therapeutic inventions which are currently being utilized for the treatment and management of bone-related diseases such as osteoporosis, rheumatoid arthritis (RA), osteogenesis imperfecta (OIM), etc., by modulating the energetics of bone cells. We further emphasized on the role of GUT-associated metabolites (GAMs) such as short-chain fatty acids (SCFAs), medium-chain fatty acids (MCFAs), indole derivates, bile acids, etc., in regulating the energetics of bone cells and their plausible role in maintaining bone health. Emphasis is importantly placed on highlighting knowledge gaps in this novel field of skeletal biology, i.e., "Osteometabolism" (proposed by our group) that need to be further explored to characterize the physiological importance of skeletal cell bioenergetics in the context of human health and bone related metabolic diseases.
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Affiliation(s)
- Rupesh K. Srivastava
- Translational Immunology, Osteoimmunology & Immunoporosis Lab (TIOIL), Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India
| | - Leena Sapra
- Translational Immunology, Osteoimmunology & Immunoporosis Lab (TIOIL), Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India
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16
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Zuo H, Zheng T, Wu K, Yang T, Wang L, Nima Q, Bai H, Dong K, Fan Z, Huang S, Luo R, Wu J, Zhou J, Xu H, Zhang Y, Feng S, Zeng P, Xiao X, Guo B, Wei Y, Pei X, Zhao X. High-altitude exposure decreases bone mineral density and its relationship with gut microbiota: Results from the China multi-ethnic cohort (CMEC) study. ENVIRONMENTAL RESEARCH 2022; 215:114206. [PMID: 36058270 DOI: 10.1016/j.envres.2022.114206] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 08/12/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Geographic altitude is a potent environmental factor for human microbiota and bone mineral density. However, little evidence exists in population-based studies with altitude diversity ranges across more than 3000 m. This study assessed the associations between a wide range of altitudes and bone mineral density, as well as the potential mediating role of microbiota in this relationship. METHODS A total of 99,556 participants from the China Multi-Ethnic Cohort (CMEC) study were enrolled. The altitude of each participant was extracted from global Shuttle Radar Topography Mission (SRTM) 4 data. Bone mineral density was measured by calcaneus quantitative ultrasound index (QUI). Stool samples were collected for 16S rRNA gene sequencing (n = 1384). The metabolites of gut microbiota, seven kinds of short-chain fatty acids (SCFAs), were detected by gas chromatography-mass spectrometry (GC-MS, n = 128). After screening, 73,974 participants were selected for the "altitude-QUI" analysis and they were placed into the low-altitude (LA) and high-altitude (HA) groups. Additionally, a subgroup (n = 1384) was further selected for the "altitude-microbiota-QUI" analysis. Multivariate linear regression models and mediation analyses were conducted among participants. RESULTS A significant negative association between high-altitude and QUI was obtained (mean difference = -0.373 standard deviation [SD], 95% confidence interval [CI]: -0.389, -0.358, n = 73,974). The same negative association was also observed in the population with microbiota data (mean difference = -0.185 SD, 95%CI: -0.360, -0.010, n = 1384), and a significant mediating effect of Catenibacteriumon on the association between altitude and QUI (proportion mediated = 25.2%, P = 0.038) was also noticed. Additionally, the acetic acid, butyric acid, and total amount of seven SCFAs of the low-altitude group were significantly higher than that of the high-altitude group (P < 0.05). CONCLUSION High-altitude exposure may decrease bone mineral density in adults, thus increasing the risk of osteoporosis. The modulation of gut microbiota may be a potential strategy for alleviating the decrease of bone mineral density.
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Affiliation(s)
- Haojiang Zuo
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Tianli Zheng
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Kunpeng Wu
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Tingting Yang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, China.
| | - Lingyao Wang
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Qucuo Nima
- Tibet Center for Disease Control and Prevention, Lhasa City, Tibet Autonomous Region, 850000, China.
| | - Hua Bai
- College of Public Health, Kunming Medical University, Kunming, 650500, China.
| | - Ke Dong
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Ziwei Fan
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Shourui Huang
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Ruocheng Luo
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Jialong Wu
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Junmin Zhou
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Huan Xu
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Yingcong Zhang
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Shiyu Feng
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Peibin Zeng
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Xiong Xiao
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Bing Guo
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
| | - Yonglan Wei
- Chengdu Center for Disease Control and Prevention, Chengdu, Sichuan, 610041, China.
| | - Xiaofang Pei
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China; Food Safety Monitoring and Risk Assessment Key Laboratory of Sichuan Province, 610041, Chengdu, China.
| | - Xing Zhao
- West China School of Public Health and West China Fourth Hospital, Sichuan University, 610041, Chengdu, China.
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17
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Johnston SN, Madhu V, Shapiro IM, Risbud MV. Conditional Deletion of HIF-2α in Mouse Nucleus Pulposus Reduces Fibrosis and Provides Mild and Transient Protection From Age-Dependent Structural Changes in Intervertebral Disc. J Bone Miner Res 2022; 37:2512-2530. [PMID: 36117450 PMCID: PMC9772060 DOI: 10.1002/jbmr.4707] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/05/2022] [Accepted: 07/29/2022] [Indexed: 01/19/2023]
Abstract
Hypoxia-inducible factors (HIFs) are critical to the development and homeostasis of hypoxic tissues. Although HIF-2α, one of the main HIF-α isoforms, is expressed in nucleus pulposus (NP) cells, its functions remain unknown. We deleted HIF-2α in the NP tissue using a notochord-specific FoxA2Cre allele to study HIF-2α function in the adult intervertebral disc. Unlike observations in HIF-1αcKO mice, fate mapping studies using Rosa26-mTmG reporter showed that HIF-2α loss in NP did not negatively impact cell survival or affect compartment development. Rather, loss of HIF-2α resulted in slightly better attributes of NP morphology in 14-month-old HIF-2αcKO mice as evident from lower scores of degeneration. These 14-month-old HIF-2αcKO mice also exhibited significant reduction in NP tissue fibrosis and lower collagen turnover in the annulus fibrosis (AF) compartment. Imaging-Fourier transform-infrared (FTIR) analyses showed decreased collagen and protein content in the NP and maintained chondroitin sulfate levels in 14-month-old HIF-2αcKO . Mechanistically, global transcriptomic analysis showed enrichment of differentially expressed genes with Gene Ontology (GO) terms related to metabolic processes and cell development, molecular functions concerned with histone and protein binding, and associated pathways, including oxidative stress. Noteworthy, these morphological differences were not apparent in 24-month-old HIF-2αcKO , indicating that aging is the dominant factor in governing disc health. Together these data suggest that loss of HIF-2α in the NP compartment is not detrimental to the intervertebral disc development but rather mitigates NP tissue fibrosis and offers mild but transient protection from age-dependent early degenerative changes. © 2022 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Shira N. Johnston
- Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Vedavathi Madhu
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Irving M. Shapiro
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
| | - Makarand V. Risbud
- Graduate Program in Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA USA
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA USA
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18
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Babu LK, Ghosh D. Looking at Mountains: Role of Sustained Hypoxia in Regulating Bone Mineral Homeostasis in Relation to Wnt Pathway and Estrogen. Clin Rev Bone Miner Metab 2022. [DOI: 10.1007/s12018-022-09283-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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19
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Analysis of Bone Histomorphometry in Rat and Guinea Pig Animal Models Subject to Hypoxia. Int J Mol Sci 2022; 23:ijms232112742. [DOI: 10.3390/ijms232112742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/19/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022] Open
Abstract
Hypoxia may be associated with alterations in bone remodeling, but the published results are contradictory. The aim of this study was to characterize the bone morphometry changes subject to hypoxia for a better understanding of the bone response to hypoxia and its possible clinical consequences on the bone metabolism. This study analyzed the bone morphometry parameters by micro-computed tomography (μCT) in rat and guinea pig normobaric hypoxia models. Adult male and female Wistar rats were exposed to chronic hypoxia for 7 and 15 days. Additionally, adult male guinea pigs were exposed to chronic hypoxia for 15 days. The results showed that rats exposed to chronic constant and intermittent hypoxic conditions had a worse trabecular and cortical bone health than control rats (under a normoxic condition). Rats under chronic constant hypoxia were associated with a more deteriorated cortical tibia thickness, trabecular femur and tibia bone volume over the total volume (BV/TV), tibia trabecular number (Tb.N), and trabecular femur and tibia bone mineral density (BMD). In the case of chronic intermittent hypoxia, rats subjected to intermittent hypoxia had a lower cortical femur tissue mineral density (TMD), lower trabecular tibia BV/TV, and lower trabecular thickness (Tb.Th) of the tibia and lower tibia Tb.N. The results also showed that obese rats under a hypoxic condition had worse values for the femur and tibia BV/TV, tibia trabecular separation (Tb.Sp), femur and tibia Tb.N, and BMD for the femur and tibia than normoweight rats under a hypoxic condition. In conclusion, hypoxia and obesity may modify bone remodeling, and thus bone microarchitecture, and they might lead to reductions in the bone strength and therefore increase the risk of fragility fracture.
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20
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Qin Q, Liu Y, Yang Z, Aimaijiang M, Ma R, Yang Y, Zhang Y, Zhou Y. Hypoxia-Inducible Factors Signaling in Osteogenesis and Skeletal Repair. Int J Mol Sci 2022; 23:ijms231911201. [PMID: 36232501 PMCID: PMC9569554 DOI: 10.3390/ijms231911201] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/10/2022] [Accepted: 09/14/2022] [Indexed: 11/23/2022] Open
Abstract
Sufficient oxygen is required to maintain normal cellular and physiological function, such as a creature’s development, breeding, and homeostasis. Lately, some researchers have reported that both pathological hypoxia and environmental hypoxia might affect bone health. Adaptation to hypoxia is a pivotal cellular event in normal cell development and differentiation and in pathological settings such as ischemia. As central mediators of homeostasis, hypoxia-inducible transcription factors (HIFs) can allow cells to survive in a low-oxygen environment and are essential for the regulation of osteogenesis and skeletal repair. From this perspective, we summarized the role of HIF-1 and HIF-2 in signaling pathways implicated in bone development and skeletal repair and outlined the molecular mechanism of regulation of downstream growth factors and protein molecules such as VEGF, EPO, and so on. All of these present an opportunity for developing therapies for bone regeneration.
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21
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Ford CA, Hurford IM, Fulbright LE, Curry JM, Peek CT, Spoonmore TJ, Cruz Victorio V, Johnson JR, Peck SH, Cassat JE. Loss of Vhl alters trabecular bone loss during S. aureus osteomyelitis in a cell-specific manner. Front Cell Infect Microbiol 2022; 12:985467. [PMID: 36204648 PMCID: PMC9530664 DOI: 10.3389/fcimb.2022.985467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 08/29/2022] [Indexed: 01/07/2023] Open
Abstract
Osteomyelitis, or bone infection, is a major complication of accidental trauma or surgical procedures involving the musculoskeletal system. Staphylococcus aureus is the most frequently isolated pathogen in osteomyelitis and triggers significant bone loss. Hypoxia-inducible factor (HIF) signaling has been implicated in antibacterial immune responses as well as bone development and repair. In this study, the impact of bone cell HIF signaling on antibacterial responses and pathologic changes in bone architecture was explored using genetic models with knockout of either Hif1a or a negative regulator of HIF-1α, Vhl. Deletion of Hif1a in osteoblast-lineage cells via Osx-Cre (Hif1aΔOB ) had no impact on bacterial clearance or pathologic changes in bone architecture in a model of post-traumatic osteomyelitis. Knockout of Vhl in osteoblast-lineage cells via Osx-Cre (VhlΔOB ) caused expected increases in trabecular bone volume per total volume (BV/TV) at baseline and, intriguingly, did not exhibit an infection-mediated decline in trabecular BV/TV, unlike control mice. Despite this phenotype, bacterial burdens were not affected by loss of Vhl. In vitro studies demonstrated that transcriptional regulation of the osteoclastogenic cytokine receptor activator of NF-κB ligand (RANKL) and its inhibitor osteoprotegerin (OPG) is altered in osteoblast-lineage cells with knockout of Vhl. After observing no impact on bacterial clearance with osteoblast-lineage conditional knockouts, a LysM-Cre model was used to generate Hif1aΔMyeloid and VhlΔMyeloid mouse models to explore the impact of myeloid cell HIF signaling. In both Hif1aΔMyeloid and VhlΔMyeloid models, bacterial clearance was not impacted. Moreover, minimal impacts on bone architecture were observed. Thus, skeletal HIF signaling was not found to impact bacterial clearance in our mouse model of post-traumatic osteomyelitis, but Vhl deletion in the osteoblast lineage was found to limit infection-mediated trabecular bone loss, possibly via altered regulation of RANKL-OPG gene transcription.
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Affiliation(s)
- Caleb A. Ford
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
| | - Ian M. Hurford
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Laura E. Fulbright
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Jacob M. Curry
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Christopher T. Peek
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Thomas J. Spoonmore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, United States
| | - Virginia Cruz Victorio
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Joshua R. Johnson
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Sun H. Peck
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States
| | - James E. Cassat
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, TN, United States
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22
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Abstract
The regulatory mechanism of hypoxia-inducible factor-1α (HIF-1α) is complex. HIF-1α may inhibit or promote apoptosis in osteoblasts under different physiological conditions, and induce bone regeneration and repair injury in coordination with angiogenesis. The relationship between H2O2 and HIFs is complex, and this study aimed to explore the role of HIF-1α in H2O2-induced apoptosis. Dimethyloxallyl glycine (DMOG) and 2-Methoxyestradiol (2ME) were used to stabilize and inhibit HIFs, respectively. Cell viability was assessed with CCK8. Apoptosis and ROS levels were detected by flow cytometry, and HIF mRNA expression was assessed by reverse transcription-polymerase chain reaction (RT-PCR). Western blot was performed to detect HIF-1α, HIF-2α, Bax, Bak, Bcl-2, Bcl-XL, caspase-9, and PCNA protein amounts. Our data suggest that both HIF-1α and HIF-2α play a protective role in oxidative stress. HIF-1α reduces H2O2-induced apoptosis by upregulating Bcl-2 and Bcl-XL, downregulating Bax, Bak, and caspase-9, stabilizing intracellular ROS levels, and promoting the repair of H2O2-induced DNA damage to reduce apoptosis.
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Affiliation(s)
- Xiaohui Wang
- Department of Hematology, The First Affiliated Hospital of Guangxi Medical University, Nanning, PR China
| | - Lili Wei
- General Geriatrics Division, The First Affiliated Hospital of Guangxi Medical University, Nanning, PR China
| | - Qiaochuan Li
- Department of Hematology, The First Affiliated Hospital of Guangxi Medical University, Nanning, PR China
| | - Yongrong Lai
- Department of Hematology, The First Affiliated Hospital of Guangxi Medical University, Nanning, PR China
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23
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Usategui-Martín R, Rigual R, Ruiz-Mambrilla M, Fernández-Gómez JM, Dueñas A, Pérez-Castrillón JL. Molecular Mechanisms Involved in Hypoxia-Induced Alterations in Bone Remodeling. Int J Mol Sci 2022; 23:ijms23063233. [PMID: 35328654 PMCID: PMC8953213 DOI: 10.3390/ijms23063233] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/11/2022] [Accepted: 03/15/2022] [Indexed: 12/31/2022] Open
Abstract
Bone is crucial for the support of muscles and the protection of vital organs, and as a reservoir of calcium and phosphorus. Bone is one of the most metabolically active tissues and is continuously renewed to adapt to the changes required for healthy functioning. To maintain normal cellular and physiological bone functions sufficient oxygen is required, as evidence has shown that hypoxia may influence bone health. In this scenario, this review aimed to analyze the molecular mechanisms involved in hypoxia-induced bone remodeling alterations and their possible clinical consequences. Hypoxia has been associated with reduced bone formation and reduced osteoblast matrix mineralization due to the hypoxia environment inhibiting osteoblast differentiation. A hypoxic environment is involved with increased osteoclastogenesis and increased bone resorptive capacity of the osteoclasts. Clinical studies, although with contradictory results, have shown that hypoxia can modify bone remodeling.
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Affiliation(s)
- Ricardo Usategui-Martín
- Department of Cell Biology, Histology and Pharmacology, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
- IOBA, University of Valladolid, 47011 Valladolid, Spain
- Correspondence: (R.U.-M.); (J.L.P.-C.)
| | - Ricardo Rigual
- Department of Biochemistry, Molecular Biology and Physiology, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
- IBGM, University of Valladolid, 47003 Valladolid, Spain
| | - Marta Ruiz-Mambrilla
- Department of Surgery, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
| | - José-María Fernández-Gómez
- Department of Cell Biology, Histology and Pharmacology, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
| | - Antonio Dueñas
- Department of Medicine, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
- Department of Toxicology, Río Hortega University Hospital, 47012 Valladolid, Spain
| | - José Luis Pérez-Castrillón
- Department of Medicine, Faculty of Medicine, University of Valladolid, 47003 Valladolid, Spain;
- Department of Internal Medicine, Río Hortega University Hospital, 47012 Valladolid, Spain
- Correspondence: (R.U.-M.); (J.L.P.-C.)
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24
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Brent MB, Emmanuel T, Simonsen U, Brüel A, Thomsen JS. Hypobaric hypoxia deteriorates bone mass and strength in mice. Bone 2022; 154:116203. [PMID: 34536630 DOI: 10.1016/j.bone.2021.116203] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/30/2021] [Accepted: 09/13/2021] [Indexed: 12/20/2022]
Abstract
Mountaineers at high altitude are at increased risk of acute mountain sickness as well as high altitude pulmonary and cerebral edema. A densitometric study in mountaineers has suggested that expeditions at high altitude decrease bone mineral density. Surprisingly, the in vivo skeletal effects of hypobaric hypoxia are largely unknown, and have not been studied using advanced contemporary methods to assess bone microstructure. Eighty-four 22-week-old female mice were divided into seven groups with 12 mice in each group: 1. Baseline; 2. Normobaric, 4 weeks; 3. Hypobaric hypoxia, 4 weeks; 4. Normobaric, 8 weeks; 5. Hypobaric hypoxia, 8 weeks; 6. Normobaric, 12 weeks; and 7. Hypobaric hypoxia, 12 weeks. Hypobaric hypoxia mice were housed in hypobaric chambers at an ambient pressure of 500 mbar (5500 m altitude), while normobaric mice were housed at sea level atmospheric pressure for 4, 8, or 12 weeks, respectively. Hypobaric hypoxia had a profound impact on femoral cortical bone and L4 trabecular bone, while the effect on femoral trabecular bone was less pronounced. Hypobaric hypoxia reduced the bone strength of the femoral mid-diaphysis and L4 at all time-points. At femoral cortical bone, hypobaric hypoxia reduced bone formation through fewer mineralizing surfaces and lower bone formation rate after 2 weeks. In addition, bone strength decreased, and C-terminal telopeptide of type I collagen (CTX-I) increased independently of the duration of exposure to simulated high altitude. At L4, hypobaric hypoxia resulted in a substantial reduction in bone volume fraction, trabecular thickness, and trabecular number after 4 weeks of exposure. Hypobaric hypoxia reduced bone strength and femoral bone mass, while femoral trabecular bone was much less affected, indicating the skeletal response to hypobaric hypoxia differ between cortical and trabecular bone. These findings provide initial preclinical support for future clinical studies in mountaineers to assess bone status and bone strength after exposure to prolonged high altitude exposure.
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Affiliation(s)
- Mikkel Bo Brent
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
| | - Thomas Emmanuel
- Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Ulf Simonsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Annemarie Brüel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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25
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Woźniczka M, Błaszczak-Świątkiewicz K. New Generation of Meso and Antiprogestins (SPRMs) into the Osteoporosis Approach. Molecules 2021; 26:6491. [PMID: 34770897 PMCID: PMC8588216 DOI: 10.3390/molecules26216491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 10/04/2021] [Accepted: 10/19/2021] [Indexed: 01/09/2023] Open
Abstract
Receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) play key roles in bone metabolism and the immune system. The RANK/RANKL complex has also been shown to be critical in the formation of mammary epithelia cells. The female hormones estradiol and progesterone closely control the action of RANKL with RANK. Blood concentration of these sex hormones in the postmenopausal period leads to an increase in RANK/RANKL signaling and are a major cause of women's osteoporosis, characterized by altered bone mineralization. Knowledge of the biochemical relationships between hormones and RANK/RANKL signaling provides the opportunity to design novel therapeutic agents to inhibit bone loss, based on the anti-RANKL treatment and inhibition of its interaction with the RANK receptor. The new generation of both anti- and mesoprogestins that inhibit the NF-κB-cyclin D1 axis and blocks the binding of RANKL to RANK can be considered as a potential source of new RANK receptor ligands with anti-RANKL function, which may provide a new perspective into osteoporosis treatment itself as well as limit the osteoporosis rise during breast cancer metastasis to the bone.
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Affiliation(s)
| | - Katarzyna Błaszczak-Świątkiewicz
- Department of Physical and Biocoordination Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Lodz, Poland;
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26
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Che X, Park NR, Jin X, Jung YK, Han MS, Park CY, Chun JS, Kim SG, Jin J, Kim HJ, Lian JB, Stein JL, Stein GS, Choi JY. Hypoxia-inducible factor 2α is a novel inhibitor of chondrocyte maturation. J Cell Physiol 2021; 236:6963-6973. [PMID: 33748969 PMCID: PMC8662706 DOI: 10.1002/jcp.30356] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/19/2022]
Abstract
Hypoxic environment is essential for chondrocyte maturation and longitudinal bone growth. Although hypoxia-inducible factor 1 alpha (Hif-1α) has been known as a key player for chondrocyte survival and function, the function of Hif-2α in cartilage is mechanistically and clinically relevant but remains unknown. Here we demonstrated that Hif-2α was a novel inhibitor of chondrocyte maturation through downregulation of Runx2 stability. Mechanistically, Hif-2α binding to Runx2 inhibited chondrocyte maturation by Runx2 degradation through disrupting Runx2/Cbfβ complex formation. The Hif-2α-mediated-Runx2 degradation could be rescued by Cbfβ transfection due to the increase of Runx2/Cbfβ complex formation. Consistently, mesenchymal cells derived from Hif-2α heterozygous mice were more rapidly differentiated into hypertrophic chondrocytes than those of wild-type mice in a micromass culture system. Collectively, these findings demonstrate that Hif-2α is a novel inhibitor for chondrocyte maturation by disrupting Runx2/Cbfβ complex formation and consequential regulatory activity.
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Affiliation(s)
- Xiangguo Che
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Na-Rae Park
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Xian Jin
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Youn-Kwan Jung
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Min-Su Han
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Clara Yongjoo Park
- Department of Food and Nutrition, Human Ecology Research Institute, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jang-Soo Chun
- Cell Dynamics Research Center, School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Seong-Gon Kim
- Department of Oral and Maxillofacial Surgery, College of Dentistry, Gangneung-Wonju National University, Gangneung, 25457, Republic of Korea
| | - Jingchun Jin
- Department of Immunology of Yanbian University Hospital, 133000, Yanji, Jilin Province, China
| | - Hyun-Ju Kim
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
| | - Jane B. Lian
- Department of Biochemistry and University of Vermont Cancer Center, University of Vermont College of Medicine, Brulington, VT 05405, U.S.A
| | - Janet L. Stein
- Department of Biochemistry and University of Vermont Cancer Center, University of Vermont College of Medicine, Brulington, VT 05405, U.S.A
| | - Gary S. Stein
- Department of Biochemistry and University of Vermont Cancer Center, University of Vermont College of Medicine, Brulington, VT 05405, U.S.A
| | - Je-Yong Choi
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Korea Mouse Phenotyping Center, School of Medicine, Kyungpook National University, Daegu 41944 Korea
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27
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Abstract
Intermuscular bones (IBs) are slender linear bones embedded in muscle, which ossify from tendons through a process of intramembranous ossification, and only exist in basal teleosts. IBs are essential for fish swimming, but they present a choking risk during human consumption, especially in children, which can lead to commercial risks that have a negative impact on the aquaculture of these fish. In this review, we discuss the morphogenesis and functions of IBs, including their underlying molecular mechanisms, as well as the advantages and disadvantages of different methods for IB studies and techniques for breeding and generating IB-free fish lines. This review reveals that the many key genes involved in tendon development, osteoblast differentiation, and bone formation, e.g., scxa, msxC, sost, twist, bmps, and osterix, also play roles in IB development. Thus, this paper provides useful information for the breeding of new fish strains without IBs via genome editing and artificial selection.
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Affiliation(s)
- Bo Li
- Cave Fish Development and Evolution Research Group, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.,College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Yuan-Wei Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.,Yunnan Key Laboratory of Plateau Fish Breeding, Yunnan Engineering Research Center for Plateau-Lake Health and Restoration, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Xiao Liu
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Li Ma
- Cave Fish Development and Evolution Research Group, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China. E-mail:
| | - Jun-Xing Yang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.,Yunnan Key Laboratory of Plateau Fish Breeding, Yunnan Engineering Research Center for Plateau-Lake Health and Restoration, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China. E-mail:
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28
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Xue C, Pan W, Lu X, Guo J, Xu G, Sheng Y, Yuan G, Zhao N, Sun J, Guo X, Wang M, Li H, Du P, An L, Han X. Effects of compound deer bone extract on osteoporosis model mice and intestinal microflora. J Food Biochem 2021; 45:e13740. [PMID: 33904182 DOI: 10.1111/jfbc.13740] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 04/01/2021] [Accepted: 04/05/2021] [Indexed: 12/26/2022]
Abstract
The preventive and therapeutic mechanisms of CDBE on osteoporosis were studied by observing the serum bone-related biochemical indicators, bone trabecular micro-structure and intestinal flora in ovariectomized osteoporosis model mice, in order to provide a scientific theoretical basis for the further study on the effect of CDBE on osteoporosis, and the prevention and treatment of osteoporosis with clinical traditional Chinese medicines. The components in CDBE were detected by UHPLC-MS. A mouse osteoporosis model was established by the bilateral ovariectomy in female ICR mice. The biochemical indicators related to osteoporosis were detected, the right proximal tibia was scanned by Micro-CT, the intestinal microflora in the colon contents were examined, and the changes of microflora were taken as the main target to evaluate the effect of CDBE on the intestinal microflora in the model mice. A total of 16 compounds were obtained by the combined application of UHPLC-MS. CDBE could significantly increase the contents of E2, Ca2+ , CT, HyP, OCN, FOXP3, P1NP and CTX-II, in the model mice. CDBE could significantly improve the trabecular micro-structure, Tb.N, Tb.Sp, SMI and Conn.D. CDBE could make the intestinal flora of osteoporosis model mice tend to healthy mice in species and quantity. CDBE can improve the symptoms of postmenopausal osteoporosis in mice, with a positive effect on the intestinal flora of postmenopausal mice. Its mechanism of regulating the symptoms of osteoporosis may be related to the regulation of bone-related biochemical indicators in the serum of mice. PRACTICAL APPLICATIONS: This research has a positive impact on the development of functional food with anti-osteoporosis in the future.
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Affiliation(s)
- Chuang Xue
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Wang Pan
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Xuechun Lu
- Department of Hematology, General Hospital of the Chinese People's Liberation Army, Beijing, China
| | - Jingru Guo
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Guangyu Xu
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Yu Sheng
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Guangxin Yuan
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Nanxi Zhao
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Jingbo Sun
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Xiao Guo
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Manli Wang
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Hongyu Li
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Peige Du
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Liping An
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
| | - Xiao Han
- Department of Pharmaceutical Analysis, College of Pharmacy, Beihua University, Jilin, China
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Lee SY, Park KH, Lee G, Kim SJ, Song WH, Kwon SH, Koh JT, Huh YH, Ryu JH. Hypoxia-inducible factor-2α mediates senescence-associated intrinsic mechanisms of age-related bone loss. Exp Mol Med 2021; 53:591-604. [PMID: 33811248 PMCID: PMC8102580 DOI: 10.1038/s12276-021-00594-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 02/01/2023] Open
Abstract
Aging is associated with cellular senescence followed by bone loss leading to bone fragility in humans. However, the regulators associated with cellular senescence in aged bones need to be identified. Hypoxia-inducible factor (HIF)-2α regulates bone remodeling via the differentiation of osteoblasts and osteoclasts. Here, we report that HIF-2α expression was highly upregulated in aged bones. HIF-2α depletion in male mice reversed age-induced bone loss, as evidenced by an increase in the number of osteoblasts and a decrease in the number of osteoclasts. In an in vitro model of doxorubicin-mediated senescence, the expression of Hif-2α and p21, a senescence marker gene, was enhanced, and osteoblastic differentiation of primary mouse calvarial preosteoblast cells was inhibited. Inhibition of senescence-induced upregulation of HIF-2α expression during matrix maturation, but not during the proliferation stage of osteoblast differentiation, reversed the age-related decrease in Runx2 and Ocn expression. However, HIF-2α knockdown did not affect p21 expression or senescence progression, indicating that HIF-2α expression upregulation in senescent osteoblasts may be a result of aging rather than a cause of cellular senescence. Osteoclasts are known to induce a senescent phenotype during in vitro osteoclastogenesis. Consistent with increased HIF-2α expression, the expression of p16 and p21 was upregulated during osteoclastogenesis of bone marrow macrophages. ChIP following overexpression or knockdown of HIF-2α using adenovirus revealed that p16 and p21 are direct targets of HIF-2α in osteoclasts. Osteoblast-specific (Hif-2αfl/fl;Col1a1-Cre) or osteoclast-specific (Hif-2αfl/fl;Ctsk-Cre) conditional knockout of HIF-2α in male mice reversed age-related bone loss. Collectively, our results suggest that HIF-2α acts as a senescence-related intrinsic factor in age-related dysfunction of bone homeostasis.
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Affiliation(s)
- Sun Young Lee
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Ka Hyon Park
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Gyuseok Lee
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Su-Jin Kim
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea ,grid.14005.300000 0001 0356 9399Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Won-Hyun Song
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea ,grid.14005.300000 0001 0356 9399Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Seung-Hee Kwon
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea ,grid.14005.300000 0001 0356 9399Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Jeong-Tae Koh
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea ,grid.14005.300000 0001 0356 9399Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
| | - Yun Hyun Huh
- grid.61221.360000 0001 1033 9831School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005 Republic of Korea
| | - Je-Hwang Ryu
- grid.14005.300000 0001 0356 9399Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea ,grid.14005.300000 0001 0356 9399Hard-tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju, 61186 Republic of Korea
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Meng X, Wielockx B, Rauner M, Bozec A. Hypoxia-Inducible Factors Regulate Osteoclasts in Health and Disease. Front Cell Dev Biol 2021; 9:658893. [PMID: 33816509 PMCID: PMC8014084 DOI: 10.3389/fcell.2021.658893] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 02/18/2021] [Indexed: 12/14/2022] Open
Abstract
Hypoxia-inducible factors (HIFs) have become key transcriptional regulators of metabolism, angiogenesis, erythropoiesis, proliferation, inflammation and metastases. HIFs are tightly regulated by the tissue microenvironment. Under the influence of the hypoxic milieu, HIF proteins allow the tissue to adapt its response. This is especially critical for bone, as it constitutes a highly hypoxic environment. As such, bone structure and turnover are strongly influenced by the modulation of oxygen availability and HIFs. Both, bone forming osteoblasts and bone resorbing osteoclasts are targeted by HIFs and modulators of oxygen tension. Experimental and clinical data have delineated the importance of HIF responses in different osteoclast-mediated pathologies. This review will focus on the influence of HIF expression on the regulation of osteoclasts in homeostasis as well as during inflammatory and malignant bone diseases.
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Affiliation(s)
- Xianyi Meng
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nurnberg (FAU) and Universitatsklinikum Erlangen, Erlangen, Germany
| | - Ben Wielockx
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Martina Rauner
- Department of Medicine 3 - Division of Molecular Bone Biology, Medical Faculty of the Technische Universität Dresden, Dresden, Germany
| | - Aline Bozec
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nurnberg (FAU) and Universitatsklinikum Erlangen, Erlangen, Germany
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Nishida D, Arai A, Zhao L, Yang M, Nakamichi Y, Horibe K, Hosoya A, Kobayashi Y, Udagawa N, Mizoguchi T. RANKL/OPG ratio regulates odontoclastogenesis in damaged dental pulp. Sci Rep 2021; 11:4575. [PMID: 33633362 PMCID: PMC7907144 DOI: 10.1038/s41598-021-84354-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 02/16/2021] [Indexed: 01/31/2023] Open
Abstract
Bone-resorbing osteoclasts are regulated by the relative ratio of the differentiation factor, receptor activator NF-kappa B ligand (RANKL) and its decoy receptor, osteoprotegerin (OPG). Dental tissue-localized-resorbing cells called odontoclasts have regulatory factors considered as identical to those of osteoclasts; however, it is still unclear whether the RANKL/OPG ratio is a key factor for odontoclast regulation in dental pulp. Here, we showed that odontoclast regulators, macrophage colony-stimulating factor-1, RANKL, and OPG were detectable in mouse pulp of molars, but OPG was dominantly expressed. High OPG expression was expected to have a negative regulatory effect on odontoclastogenesis; however, odontoclasts were not detected in the dental pulp of OPG-deficient (KO) mice. In contrast, damage induced odontoclast-like cells were seen in wild-type pulp tissues, with their number significantly increased in OPG-KO mice. Relative ratio of RANKL/OPG in the damaged pulp was significantly higher than in undamaged control pulp. Pulp damages enhanced hypoxia inducible factor-1α and -2α, reported to increase RANKL or decrease OPG. These results reveal that the relative ratio of RANKL/OPG is significant to pulpal odontoclastogenesis, and that OPG expression is not required for maintenance of pulp homeostasis, but protects pulp from odontoclastogenesis caused by damages.
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Affiliation(s)
- Daisuke Nishida
- grid.265070.60000 0001 1092 3624Oral Health Science Center, Tokyo Dental College, Tokyo, 101-0061 Japan
| | - Atsushi Arai
- grid.411611.20000 0004 0372 3845Department of Orthodontics, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Lijuan Zhao
- grid.411611.20000 0004 0372 3845Institute for Oral Science, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Mengyu Yang
- grid.411611.20000 0004 0372 3845Institute for Oral Science, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Yuko Nakamichi
- grid.411611.20000 0004 0372 3845Institute for Oral Science, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Kanji Horibe
- grid.411611.20000 0004 0372 3845Department of Oral Histology, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Akihiro Hosoya
- grid.412021.40000 0004 1769 5590Department of Histology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, 061-0293 Japan
| | - Yasuhiro Kobayashi
- grid.411611.20000 0004 0372 3845Institute for Oral Science, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Nobuyuki Udagawa
- grid.411611.20000 0004 0372 3845Department of Oral Biochemistry, Matsumoto Dental University, Nagano, 399-0781 Japan
| | - Toshihide Mizoguchi
- grid.265070.60000 0001 1092 3624Oral Health Science Center, Tokyo Dental College, Tokyo, 101-0061 Japan ,grid.411611.20000 0004 0372 3845Department of Oral Biochemistry, Matsumoto Dental University, Nagano, 399-0781 Japan
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32
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Distinct roles for the hypoxia-inducible transcription factors HIF-1α and HIF-2α in human osteoclast formation and function. Sci Rep 2020; 10:21072. [PMID: 33273561 PMCID: PMC7713367 DOI: 10.1038/s41598-020-78003-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/19/2020] [Indexed: 01/04/2023] Open
Abstract
Bone homeostasis is maintained by a balance between osteoblast-mediated bone formation and osteoclast-driven bone resorption. Hypoxia modulates this relationship partially via direct and indirect effects of the hypoxia-inducible factor-1 alpha (HIF-1α) transcription factor on osteoclast formation and bone resorption. Little data is available on the role(s) of the HIF-2α isoform of HIF in osteoclast biology. Here we describe induction of HIF-1α and HIF-2α during the differentiation of human CD14+ monocytes into osteoclasts. Knockdown of HIF-1α did not affect osteoclast differentiation but prevented the increase in bone resorption that occurs under hypoxic conditions. HIF-2α knockdown did not affect bone resorption but moderately inhibited osteoclast formation. Growth of osteoclasts in 3D gels reversed the effect of HIF-2α knockdown; HIF-2α siRNA increasing osteoclast formation in 3D. Glycolysis is the main HIF-regulated pathway that drives bone resorption. HIF knockdown only affected glucose uptake and bone resorption in hypoxic conditions. Inhibition of glycolysis with 2-deoxy-d-glucose (2-DG) reduced osteoclast formation and activity under both basal and hypoxic conditions, emphasising the importance of glycolytic metabolism in osteoclast biology. In summary, HIF-1α and HIF-2α play different but overlapping roles in osteoclast biology, highlighting the importance of the HIF pathway as a potential therapeutic target in osteolytic disease.
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33
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Todd VM, Johnson RW. Hypoxia in bone metastasis and osteolysis. Cancer Lett 2020; 489:144-154. [PMID: 32561416 PMCID: PMC7429356 DOI: 10.1016/j.canlet.2020.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/15/2020] [Accepted: 06/01/2020] [Indexed: 12/19/2022]
Abstract
Hypoxia is a common feature in tumors, driving pathways that promote epithelial-to-mesenchymal transition, invasion, and metastasis. Clinically, high levels of hypoxia-inducible factor (HIF) expression and stabilization at the primary site in many cancer types is associated with poor patient outcomes. Experimental evidence suggests that HIF signaling in the primary tumor promotes their dissemination to the bone, as well as the release of factors such as LOX that act distantly on the bone to stimulate osteolysis and form a pre-metastatic niche. Additionally, the bone itself is a generally hypoxic organ, fueling the activation of HIF signaling in bone resident cells, promoting tumor cell homing to the bone as well as osteoclastogenesis. The hypoxic microenvironment of the bone also stimulates the vicious cycle of tumor-induced bone destruction, further fueling tumor cell growth and osteolysis. Furthermore, hypoxia appears to regulate key tumor dormancy factors. Thus, hypoxia acts both on the tumor cells as well as the metastatic site to promote tumor cell metastasis.
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Affiliation(s)
- Vera M Todd
- Graduate Program in Cancer Biology, Vanderbilt University, Nashville, TN, USA; Vanderbilt Center for Bone Biology, Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rachelle W Johnson
- Graduate Program in Cancer Biology, Vanderbilt University, Nashville, TN, USA; Vanderbilt Center for Bone Biology, Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA.
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34
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Nguyen VT, Nardini M, Ruggiu A, Cancedda R, Descalzi F, Mastrogiacomo M. Platelet Lysate Induces in Human Osteoblasts Resumption of Cell Proliferation and Activation of Pathways Relevant for Revascularization and Regeneration of Damaged Bone. Int J Mol Sci 2020; 21:ijms21145123. [PMID: 32698534 PMCID: PMC7403959 DOI: 10.3390/ijms21145123] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/13/2020] [Accepted: 07/16/2020] [Indexed: 12/17/2022] Open
Abstract
To understand the regenerative effect of platelet-released molecules in bone repair one should investigate the cascade of events involving the resident osteoblast population during the reconstructive process. Here the in vitro response of human osteoblasts to a platelet lysate (PL) stimulus is reported. Quiescent or very slow dividing osteoblasts showed a burst of proliferation after PL stimulation and returned to a none or very slow dividing condition when the PL was removed. PL stimulated osteoblasts maintained a differentiation capability in vitro and in vivo when tested in absence of PL. Since angiogenesis plays a crucial role in the bone healing process, we investigated in PL stimulated osteoblasts the activation of hypoxia-inducible factor 1-alpha (HIF-1α) and signal transducer and activator of transcription 3 (STAT3) pathways, involved in both angiogenesis and bone regeneration. We observed phosphorylation of STAT3 and a strong induction, nuclear translocation and DNA binding of HIF-1α. In agreement with the induction of HIF-1α an enhanced secretion of vascular endothelial growth factor (VEGF) occurred. The double effect of the PL on quiescent osteoblasts, i.e., resumption of proliferation and activation of pathways promoting both angiogenesis and bone formation, provides a rationale to the application of PL as therapeutic agent in post-traumatic bone repair.
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Affiliation(s)
- Van Thi Nguyen
- Department of Experimental Medicine (DIMES), University of Genova, 16132 Genova, Italy; (V.T.N.); (A.R.); (F.D.)
| | - Marta Nardini
- Department of Internal Medicine (DIMI), University of Genova, 16132 Genova, Italy;
- Biotherapy Unit, Ospedale Policlinico San Martino, 16132 Genova, Italy
| | - Alessandra Ruggiu
- Department of Experimental Medicine (DIMES), University of Genova, 16132 Genova, Italy; (V.T.N.); (A.R.); (F.D.)
| | | | - Fiorella Descalzi
- Department of Experimental Medicine (DIMES), University of Genova, 16132 Genova, Italy; (V.T.N.); (A.R.); (F.D.)
| | - Maddalena Mastrogiacomo
- Department of Internal Medicine (DIMI), University of Genova, 16132 Genova, Italy;
- Biotherapy Unit, Ospedale Policlinico San Martino, 16132 Genova, Italy
- Center for Biomedical Research (CEBR), University of Genova, 16132 Genova, Italy
- Correspondence: ; Tel.: +39-010-555-8203
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Hulley PA, Papadimitriou-Olivgeri I, Knowles HJ. Osteoblast-Osteoclast Coculture Amplifies Inhibitory Effects of FG-4592 on Human Osteoclastogenesis and Reduces Bone Resorption. JBMR Plus 2020; 4:e10370. [PMID: 32666021 PMCID: PMC7340438 DOI: 10.1002/jbm4.10370] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/31/2020] [Accepted: 04/19/2020] [Indexed: 12/13/2022] Open
Abstract
The link between bone and blood vessels is regulated by hypoxia and the hypoxia‐inducible transcription factor, HIF, which drives both osteogenesis and angiogenesis. The recent clinical approval of PHD enzyme inhibitors, which stabilize HIF protein, introduces the potential for a new clinical strategy to treat osteolytic conditions such as osteoporosis, osteonecrosis, and skeletal fracture and nonunion. However, bone‐resorbing osteoclasts also play a central role in bone remodeling and pathological osteolysis, and HIF promotes osteoclast activation and bone loss in vitro. It is therefore likely that the result of PHD enzyme inhibition in vivo would be mediated by a balance between increased bone formation and increased bone resorption. It is essential that we improve our understanding of the effects of HIF on osteoclast formation and function and consider the potential contribution of inhibitory interactions with other musculoskeletal cells. The PHD enzyme inhibitor FG‐4592 stabilized HIF protein and stimulated osteoclast‐mediated bone resorption, but inhibited differentiation of human CD14+ monocytes into osteoclasts. Formation of osteoclasts in a more physiologically relevant 3D collagen gel did not affect the sensitivity of osteoclastogenesis to FG‐4592, but increased sensitivity to reduced concentrations of RANKL. Coculture with osteoblasts amplified inhibition of osteoclastogenesis by FG‐4592, whether the osteoblasts were proliferating, differentiating, or in the presence of exogenous M‐CSF and RANKL. Osteoblast coculture dampened the ability of high concentrations of FG‐4592 to increase bone resorption. These data provide support for the therapeutic use of PHD enzyme inhibitors to improve bone formation and/or reduce bone loss for the treatment of osteolytic pathologies and indicate that FG‐4592 might act in vivo to inhibit the formation and activity of the osteoclasts that drive osteolysis. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Philippa A Hulley
- Nuffield Department of Orthopaedics Rheumatology & Musculoskeletal Sciences University of Oxford Oxford UK
| | - Ioanna Papadimitriou-Olivgeri
- Nuffield Department of Orthopaedics Rheumatology & Musculoskeletal Sciences University of Oxford Oxford UK.,Department of Anatomy Histology & Embryology University of Patras Patras Greece
| | - Helen J Knowles
- Nuffield Department of Orthopaedics Rheumatology & Musculoskeletal Sciences University of Oxford Oxford UK
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Hannah SS, McFadden S, McNeilly A, McClean C. "Take My Bone Away?" Hypoxia and bone: A narrative review. J Cell Physiol 2020; 236:721-740. [PMID: 32643217 DOI: 10.1002/jcp.29921] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022]
Abstract
To maintain normal cellular and physiological function, sufficient oxygen is required. Recently, evidence has suggested that hypoxia, either pathological or environmental, may influence bone health. It appears that bone cells are distinctly responsive to hypoxic stimuli; for better or worse, this is still yet to be elucidated. Hypoxia has been shown to offer potentially therapeutic effects for bone by inducing an osteogenic-angiogenic response, although, others have noted excessive osteoclastic bone resorption instead. Much evidence suggests that the hypoxic-inducible pathway is integral in mediating the changes in bone metabolism. Furthermore, many factors associated with hypoxia including changes in energy metabolism, acid-base balance and the increased generation of reactive oxygen species, are known to influence bone metabolism. This review aims to examine some of the putative mechanisms responsible for hypoxic-induced alterations of bone metabolism, with regard to osteoclasts and osteoblasts, both positive and negative.
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Affiliation(s)
- Scott S Hannah
- Sport and Exercise Sciences Research Institute, Ulster University, Newtownabbey, Antrim, UK
| | - Sonyia McFadden
- Institute of Nursing and Health Research, Ulster University, Newtownabbey, Antrim, UK
| | - Andrea McNeilly
- Sport and Exercise Sciences Research Institute, Ulster University, Newtownabbey, Antrim, UK
| | - Conor McClean
- Sport and Exercise Sciences Research Institute, Ulster University, Newtownabbey, Antrim, UK
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Sperry MM, Yu YH, Kartha S, Ghimire P, Welch RL, Winkelstein BA, Granquist EJ. Intra-articular etanercept attenuates pain and hypoxia from TMJ loading in the rat. J Orthop Res 2020; 38:1316-1326. [PMID: 31903618 PMCID: PMC9118642 DOI: 10.1002/jor.24581] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 12/28/2019] [Indexed: 02/04/2023]
Abstract
Mechanical overloading of the temporomandibular joint (TMJ) and biochemical changes, like inflammation and hypoxia, contribute to cartilage degeneration and pain associated with osteoarthritis (OA). Yet, how overloading contributes to early dysregulation of chondrocytes is not understood, limiting the development of diagnostics and treatments for TMJ OA. Hypoxia-inducible factors (HIF)-1α/2α in chondrocytes were evaluated at Days 8 and 15 in a rat TMJ pain model induced by jaw loading (1 h/day for 7 days) using immunohistochemistry and compared between cases that induce persistent (3.5 N), acute (2 N), or no (0 N) sensitivity. Hypoxia was measured on Day 8 by immunolabeling of the tracer EF5 and 18 F-EF5 PET imaging. To assess the role of tumor necrosis factor (TNF) in painful TMJ loading, intra-articular etanercept was given before loading. Orofacial sensitivity was evaluated during and after loading. Facial grimace, TNF-α, HIF-2α, and hypoxia levels in the TMJ were measured after loading. HIF-2α was elevated (P = .03) after 3.5 N loading at Day 8, but HIF-1α was unchanged. EF5 uptake increased on Day 8 in the 3.5 N group (P < .048) by tissue assay and 18 F-EF5 PET. At Day 8, both HIF-2α (P = .01) and EF5 uptake (P = .005) were correlated with loading magnitude. Etanercept attenuated sensitivity (P < .01) and the facial grimace on Day 7 (P = .01). It also reduced (P < .01) HIF-2α and EF5 uptake on Day 8; but TNF-α levels were not different from controls at that time. Findings suggest that TMJ loading that induces persistent sensitivity upregulates the catabolic factor HIF-2α and reduces oxygen levels in the cartilage, which may be TNF-driven.
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Affiliation(s)
| | - Ya-Hsin Yu
- Department of Endodontics, University of Pennsylvania School of Dental Medicine
| | - Sonia Kartha
- Department of Bioengineering, University of Pennsylvania
| | | | | | - Beth A. Winkelstein
- Department of Bioengineering, University of Pennsylvania
- Department of Neurosurgery, University of Pennsylvania
| | - Eric J. Granquist
- Oral & Maxillofacial Surgery, University of Pennsylvania School of Medicine
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Rosenblum JS, Cappadona AJ, Argersinger DP, Pang Y, Wang H, Nazari MA, Munasinghe JP, Donahue DR, Jha A, Smirniotopoulos JG, Miettinen MM, Knutsen RH, Kozel BA, Zhuang Z, Pacak K, Heiss JD. Neuraxial dysraphism in EPAS1-associated syndrome due to improper mesenchymal transition. NEUROLOGY-GENETICS 2020; 6:e414. [PMID: 32337341 PMCID: PMC7164966 DOI: 10.1212/nxg.0000000000000414] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 02/06/2020] [Indexed: 01/25/2023]
Abstract
Objective To investigate the effect of somatic, postzygotic, gain-of-function mutation of Endothelial Per-Arnt-Sim (PAS) domain protein 1 (EPAS1) encoding hypoxia-inducible factor-2α (HIF-2α) on posterior fossa development and spinal dysraphism in EPAS1 gain-of-function syndrome, which consists of multiple paragangliomas, somatostatinoma, and polycythemia. Methods Patients referred to our institution for evaluation of new, recurrent, and/or metastatic paragangliomas/pheochromocytoma were confirmed for EPAS1 gain-of-function syndrome by identification of the EPAS1 gain-of-function mutation in resected tumors and/or circulating leukocytes. The posterior fossa, its contents, and the spine were evaluated retrospectively on available MRI and CT images of the head and neck performed for tumor staging and restaging. The transgenic mouse model underwent Microfil vascular perfusion and subsequent intact ex vivo 14T MRI and micro-CT as well as gross dissection, histology, and immunohistochemistry to assess the role of EPAS1 in identified malformations. Results All 8 patients with EPAS1 gain-of-function syndrome demonstrated incidental posterior fossa malformations—one Dandy-Walker variant and 7 Chiari malformations without syringomyelia. These findings were not associated with a small posterior fossa; rather, the posterior fossa volume exceeded that of its neural contents. Seven of 8 patients demonstrated spinal dysraphism; 4 of 8 demonstrated abnormal vertebral segmentation. The mouse model similarly demonstrated features of neuraxial dysraphism, including cervical myelomeningocele and spinal dysraphism, and cerebellar tonsil displacement through the foramen magnum. Histology and immunohistochemistry demonstrated incomplete mesenchymal transition in the mutant but not the control mouse. Conclusions This study characterized posterior fossa and spinal malformations seen in EPAS1 gain-of-function syndrome and suggests that gain-of-function mutation in HIF-2α results in improper mesenchymal transition.
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Affiliation(s)
- Jared S Rosenblum
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Anthony J Cappadona
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Davis P Argersinger
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Ying Pang
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Herui Wang
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Matthew A Nazari
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Jeeva P Munasinghe
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Danielle R Donahue
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Abhishek Jha
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - James G Smirniotopoulos
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Markku M Miettinen
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Russell H Knutsen
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Beth A Kozel
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Zhengping Zhuang
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - Karel Pacak
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
| | - John D Heiss
- National Institutes of Health (J.S.R., A.J.C., H.W., Z.Z.), National Cancer Institute Neuro-Oncology Branch; National Institutes of Health (D.P.A., J.D.H.), National Institute of Neurological Disorders and Stroke, Surgical Neurology Branch; National Institutes of Health (Y.P., A.J., K.P.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Section on Medical Neuroendocrinology; Georgetown Hospital (M.A.N.), Internal Medicine and Pediatrics, Washington DC; National Institutes of Health (J.P.M., D.R.D.), National Institute of Neurological Disorders and Stroke, Mouse Imaging Facility, Bethesda, MD; George Washington University (J.G.S.), Radiology, Washington DC; National Library of Medicine (J.G.S.), MedPix®; National Institutes of Health (M.M.M.), Center for Cancer Research, National Cancer Institute, Laboratory of Pathology; and National Institutes of Health (R.H.K., B.A.K.), National Heart Lung and Blood Institute, Translational Vascular Medicine Branch, Bethesda, MD
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Rosenblum JS, Maggio D, Pang Y, Nazari MA, Gonzales MK, Lechan RM, Smirniotopoulos JG, Zhuang Z, Pacak K, Heiss JD. Chiari Malformation Type 1 in EPAS1-Associated Syndrome. Int J Mol Sci 2019; 20:ijms20112819. [PMID: 31185588 PMCID: PMC6600383 DOI: 10.3390/ijms20112819] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 06/02/2019] [Accepted: 06/03/2019] [Indexed: 11/29/2022] Open
Abstract
A syndrome of multiple paragangliomas/pheochromocytomas, somatostatinoma, and polycythemia due to somatic mosaic gain-of-function mutation of EPAS1, encoding HIF-2α, was previously described. HIF-2α has been implicated in endochondral and intramembranous ossification. Abnormal bone growth of the skull base may lead to Chiari malformation type I. We report two cases of EPAS1 gain-of-function mutation syndrome with Chiari malformation and developmental skull base anomalies. Patients were referred to the Section on Medical Endocrinology, Eunice Kennedy Shriver NICHD, NIH for evaluation of recurrent and metastatic paragangliomas or pheochromocytoma. The syndrome was confirmed genetically by identification of the functional EPAS1 gain-of-function mutation in the resected tumors and circulating leukocytes. Both patients were confirmed for characteristics of EPAS1 gain-of-function mutation syndrome by complete blood count (CBC), plasma biochemistry, and computed tomography (CT) of the abdomen and pelvis. Chiari malformation type I and abnormal bony development of the posterior fossa was found on MRI and CT of the head. The present study implicates EPAS1 mutations in abnormal posterior fossa development resulting in Chiari malformation type I.
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Affiliation(s)
- Jared S Rosenblum
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Dominic Maggio
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Ying Pang
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Matthew A Nazari
- Department of Internal Medicine and Pediatrics, Georgetown University Medical Center, Washington, DC 20007, USA.
| | - Melissa K Gonzales
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Ronald M Lechan
- Division of Endocrinology, Diabetes & Metabolism, Tufts Medical Center, Boston, MA 02111, USA.
| | - James G Smirniotopoulos
- Radiology, George Washington University, Washington, DC 20052, USA.
- MedPix® National Library of Medicine, 8600 Rockville Pike Bethesda, MD 20894, USA.
| | - Zhengping Zhuang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Karel Pacak
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - John D Heiss
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
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