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Bråtveit M, Van Parys A, Olsen T, Strand E, Marienborg I, Laupsa-Borge J, Haugsgjerd TR, McCann A, Dhar I, Ueland PM, Dierkes J, Dankel SN, Nygård OK, Lysne V. Association between dietary macronutrient composition and plasma one-carbon metabolites and B-vitamin cofactors in patients with stable angina pectoris. Br J Nutr 2024; 131:1678-1690. [PMID: 38361451 PMCID: PMC11063666 DOI: 10.1017/s0007114524000473] [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: 07/03/2023] [Revised: 01/03/2024] [Accepted: 02/13/2024] [Indexed: 02/17/2024]
Abstract
Elevated plasma concentrations of several one-carbon metabolites are associated with increased CVD risk. Both diet-induced regulation and dietary content of one-carbon metabolites can influence circulating concentrations of these markers. We cross-sectionally analysed 1928 patients with suspected stable angina pectoris (geometric mean age 61), representing elevated CVD risk, to assess associations between dietary macronutrient composition (FFQ) and plasma one-carbon metabolites and related B-vitamin status markers (GC-MS/MS, LC-MS/MS or microbiological assay). Diet-metabolite associations were modelled on the continuous scale, adjusted for age, sex, BMI, smoking, alcohol and total energy intake. Average (geometric mean (95 % prediction interval)) intake was forty-nine (38, 63) energy percent (E%) from carbohydrate, thirty-one (22, 45) E% from fat and seventeen (12, 22) E% from protein. The strongest associations were seen for higher protein intake, i.e. with higher plasma pyridoxal 5'-phosphate (PLP) (% change (95 % CI) 3·1 (2·1, 4·1)), cobalamin (2·9 (2·1, 3·7)), riboflavin (2·4 (1·1, 3·7)) and folate (2·1 (1·2, 3·1)) and lower total homocysteine (tHcy) (-1·4 (-1·9, -0·9)) and methylmalonic acid (MMA) (-1·4 (-2·0, -0·8)). Substitution analyses replacing MUFA or PUFA with SFA demonstrated higher plasma concentrations of riboflavin (5·0 (0·9, 9·3) and 3·3 (1·1, 5·6)), tHcy (2·3 (0·7, 3·8) and 1·3 (0·5, 2·2)) and MMA (2·0 (0·2, 3·9) and 1·7 (0·7, 2·7)) and lower PLP (-2·5 (-5·3, 0·3) and -2·7 (-4·2, -1·2)). In conclusion, a higher protein intake and replacing saturated with MUFA and PUFA were associated with a more favourable metabolic phenotype regarding metabolites associated with CVD risk.
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Affiliation(s)
- Marianne Bråtveit
- Mohn Nutrition Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Anthea Van Parys
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Thomas Olsen
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Elin Strand
- Department of Immunology and Transfusion Medicine, Haukeland University Hospital, Bergen, Norway
| | - Ingvild Marienborg
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Johnny Laupsa-Borge
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
| | | | | | - Indu Dhar
- Mohn Nutrition Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway
- Centre for Nutrition, Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | | | - Jutta Dierkes
- Mohn Nutrition Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway
- Centre for Nutrition, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Laboratory Medicine and Pathology, Haukeland University Hospital, Bergen, Norway
| | - Simon Nitter Dankel
- Mohn Nutrition Research Laboratory, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Ottar Kjell Nygård
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
- Laboratory Medicine and Pathology, Haukeland University Hospital, Bergen, Norway
- Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
| | - Vegard Lysne
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
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2
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Guerrero-Limón G, Zappia J, Muller M. A realistic mixture of ubiquitous persistent organic pollutants affects bone and cartilage development in zebrafish by interaction with nuclear receptor signaling. PLoS One 2024; 19:e0298956. [PMID: 38547142 PMCID: PMC10977810 DOI: 10.1371/journal.pone.0298956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 02/01/2024] [Indexed: 04/02/2024] Open
Abstract
"Persistent organic pollutants (POPs)" have a plethora of deleterious effects on humans and the environment due to their bioaccumulative, persistent, and mimicking properties. Individually, each of these chemicals has been tested and its effects measured, however they are rather found as parts of complex mixtures of which we do not fully grasp the extent of their potential consequences. Here we studied the effects of realistic, environmentally relevant mixtures of 29 POPs on cartilage and bone development using zebrafish as a model species. We observed developmental issues in cartilage, in the form of diverse malformations such as micrognathia, reduced size of the Meckel's and other structures. Also, mineralized bone formation was disrupted, hence impacting the overall development of the larvae at later life stages. Assessment of the transcriptome revealed disruption of nuclear receptor pathways, such as androgen, vitamin D, and retinoic acid, that may explain the mechanisms of action of the compounds within the tested mixtures. In addition, clustering of the compounds using their chemical signatures revealed structural similarities with the model chemicals vitamin D and retinoic acid that can explain the effects and/or enhancing the phenotypes we witnessed. Further mechanistic studies will be required to fully understand this kind of molecular interactions and their repercussions in organisms. Our results contribute to the already existing catalogue of deleterious effects caused by exposure to POPs and help to understand the potential consequences in at risk populations.
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Affiliation(s)
- Gustavo Guerrero-Limón
- Laboratory for Organogenesis and Regeneration, GIGA Institute, University of Liège, Liège, Belgium
| | - Jérémie Zappia
- Bone and Cartilage Research Unit, Arthropôle Liège, Center for Interdisciplinary Research on Medicines (CIRM) Liège, Institute of Pathology, CHU-Sart Tilman, University of Liège, Liège, Belgium
| | - Marc Muller
- Laboratory for Organogenesis and Regeneration, GIGA Institute, University of Liège, Liège, Belgium
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Shao X, Tian Y, Liu J, Yan Z, Ding Y, Hao X, Wang D, Shen L, Luo E, Guo XE, Luo P, Luo W, Cai J, Jing D. Rescuing SERCA2 pump deficiency improves bone mechano-responsiveness in type 2 diabetes by shaping osteocyte calcium dynamics. Nat Commun 2024; 15:890. [PMID: 38291059 PMCID: PMC10828510 DOI: 10.1038/s41467-024-45023-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/12/2024] [Indexed: 02/01/2024] Open
Abstract
Type 2 diabetes (T2D)-related fragility fractures represent an increasingly tough medical challenge, and the current treatment options are limited. Mechanical loading is essential for maintaining bone integrity, although bone mechano-responsiveness in T2D remains poorly characterized. Herein, we report that exogenous cyclic loading-induced improvements in bone architecture and strength are compromised in both genetically spontaneous and experimentally-induced T2D mice. T2D-induced reduction in bone mechano-responsiveness is directly associated with the weakened Ca2+ oscillatory dynamics of osteocytes, although not those of osteoblasts, which is dependent on PPARα-mediated specific reduction in osteocytic SERCA2 pump expression. Treatment with the SERCA2 agonist istaroxime was demonstrated to improve T2D bone mechano-responsiveness by rescuing osteocyte Ca2+ dynamics and the associated regulation of osteoblasts and osteoclasts. Moreover, T2D-induced deterioration of bone mechano-responsiveness is blunted in mice with osteocytic SERCA2 overexpression. Collectively, our study provides mechanistic insights into T2D-mediated deterioration of bone mechano-responsiveness and identifies a promising countermeasure against T2D-associated fragility fractures.
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Affiliation(s)
- Xi Shao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Yulan Tian
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Juan Liu
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Zedong Yan
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Yuanjun Ding
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Xiaoxia Hao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Dan Wang
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Liangliang Shen
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi'an, China
| | - Erping Luo
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - X Edward Guo
- Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Peng Luo
- Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
| | - Wenjing Luo
- The Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Fourth Military Medical University, Xi'an, China.
| | - Jing Cai
- College of Basic Medicine, Shaanxi University of Chinese Medicine, Xianyang, China.
| | - Da Jing
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.
- The Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Fourth Military Medical University, Xi'an, China.
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Huang G, Chen X, Chen Y, Liu W, Chen C, Song W, Zeng G. Causal relationship between type 2 diabetes mellitus and bone mineral density: a Mendelian randomization study in an East Asian population. Osteoporos Int 2023; 34:1719-1727. [PMID: 37306802 PMCID: PMC10511588 DOI: 10.1007/s00198-023-06807-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 05/25/2023] [Indexed: 06/13/2023]
Abstract
It remains unclear whether the relationship between type 2 diabetes mellitus (T2DM) and bone mineral density (BMD) reflects causality in East Asian populations. Herein, a Mendelian randomization study conducted in East Asian population enhances the current clinical cognition that T2DM is not associated with reduction in BMD. PURPOSE A Mendelian randomization (MR) approach was utilized to investigate the relationship between type 2 diabetes mellitus (T2DM) and bone mineral density (BMD) in East Asian populations. METHODS Genome-wide association study summary data from BioBank Japan were used to identify genetic variants strongly related to T2DM risk (36,614 cases and 155,150 controls) and osteoporosis (7788 cases and 204,665 controls). Heel BMD GWAS data of 1260 East Asian people from ieu open gwas project was considered as a second outcome. Inverse variance-weighted (IVW) analysis was mainly applied; MR-Egger and the weighted median were also used to obtain robust estimates. A series of sensitivity analyses including Cochran's Q test, MR-Egger regression, and leave-one-out analysis were used to detect pleiotropy or heterogeneity. RESULTS In the main analysis, IVW estimates indicated that T2DM significantly associated with the risk of osteoporosis (odds ratio = 0.92, 95% CI: 0.86-0.99, p = 0.016) and with higher BMD (OR: 1.25, 95% CI: 1.06-1.46, p = 6.49 × 10-3). Results of comprehensive sensitivity analysis were consistent with the main causality estimate. Horizontal pleiotropy and heterogeneity were absent in our MR study. CONCLUSIONS T2DM is not associated with reduction in BMD in terms of genetic polymorphism in East Asian populations.
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Affiliation(s)
- Guiwu Huang
- Department of Joint Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Sun Yat-Sen University, Guangzhou, China
| | - Xiong Chen
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yanbo Chen
- Department of Orthopedics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yanjiangxi Road, Guangzhou, Guangdong Province, 510120, China
| | - Wenzhou Liu
- Department of Orthopedics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yanjiangxi Road, Guangzhou, Guangdong Province, 510120, China
| | - Chen Chen
- Department of Orthopedics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yanjiangxi Road, Guangzhou, Guangdong Province, 510120, China
| | - Weidong Song
- Department of Orthopedics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yanjiangxi Road, Guangzhou, Guangdong Province, 510120, China.
| | - Gang Zeng
- Department of Orthopedics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, 107 Yanjiangxi Road, Guangzhou, Guangdong Province, 510120, China.
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Murata Y, Kataoka Y, Asaumi Y, Noguchi T. Case report: a potential modulation of coronary atheroma by lowering triglyceride-rich lipoproteins with pemafibrate: insights from serial near-infrared spectroscopy imaging. Cardiovasc Diagn Ther 2023; 13:100-108. [PMID: 36864976 PMCID: PMC9971301 DOI: 10.21037/cdt-22-401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 12/07/2022] [Indexed: 02/07/2023]
Abstract
Background Pemafibrate is a potent selective peroxisome proliferator-activated receptor α modulator. Whether this agent favorable modulates atherosclerosis in vivo remains unknown. This is the first case report to evaluate serial changes of coronary atherosclerosis under pemafirate use in type 2 diabetic patients already taking a high-intensity statin. Case Description A 75-year-old gentleman was hospitalized due to peripheral artery disease, which was treated by endovascular treatment. One year later, non-ST-elevation myocardial infarction (NSTEMI) occurred and severe stenosis at his proximal segment of right coronary artery received primary percutaneous coronary intervention (PCI). Due to his suboptimal control of low-density lipoprotein cholesterol (LDL-C) level with moderate intensity statin, high-intensity one (20 mg atorvastatin) and 10 mg ezetimibe were commenced, which enabled to achieve very low LDL-C level (50 mg/dL). However, he required additional PCI due to progression of left circumflex artery one year after NSTEMI. Despite his optimally controlled LDL-C level (46 mg/dL), near-infrared spectroscopy and intravascular (NIRS/IVUS) imaging after PCI visualized the presence of lipid-rich plaque [maximum 4-mm lipid-core burden index (LCBI4mm) =482] at non-culprit segment in his right coronary artery. Given his continuing residual hypertriglyceridemia (triglyceride =248 mg/dL), 0.2 mg pemafibrate was commenced, which lowered triglyceride to 106 mg/dL. One-year follow-up NIRS/IVUS imaging was conducted to evaluate coronary atheroma. A reduction of attenuated ultrasonic signals was observed, accompanied by plaque calcification. In addition, the amount of yellow signal was lowered, and its MaxLCBI4mm was 358. Since then, this case does not experience any cardiovascular events. His LDL-C and triglyceride-rich lipoprotein levels are favourably controlled. Conclusions A delipidation of coronary atheroma, accompanied by greater plaque calcification was observed after the commencement of pemafibrate. This finding highlights potential anti-atherosclerotic benefit of pemafibrate use in patients receiving a statin.
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Affiliation(s)
- Yu Murata
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Yu Kataoka
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Yasuhide Asaumi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Teruo Noguchi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan
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Chen Y, Jiang Z, Keohane A, Hu Y. In vitro and in vivo study of the pathogenic role of PPARα in experimental periodontitis. J Appl Oral Sci 2022; 30:e20220076. [PMID: 35830121 PMCID: PMC9275397 DOI: 10.1590/1678-7757-2022-0076] [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: 02/24/2022] [Revised: 05/20/2022] [Accepted: 05/23/2022] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE The purpose of this study is to investigate the pathogenic role of PPARα in periodontal antigen treated gingival cells in vitro and in experimental periodontitis in vivo . METHODOLOGY Gingival fibroblasts, gingival epithelial cells and splenocytes were isolated from C57BL/6J wild type (WT) mice and treated with fixed P. gingivalis at for 48 hours. The mRNA levels of PPARs, TNFα, IL-1β and IL-10 were detected by Real-time quantitative PCR. Silk ligatures after being soaked in the P.gingivalis suspension were tied around both maxillary second molars of WT mice or PPARα knock-out (KO) mice for two weeks. PPARα agonist fenofibrate and vehicle control were injected into the different side of the palatal gingiva on days 3, 6, and 9. At day 14, bone resorption and gingival mRNA expression levels of PPARs, TNFα, IL-1β and IL-10 were measured by micro-computed tomography and RT-qPCR respectively. RESULTS P. gingivalis treatment downregulated the expression of PPARα, but not PPARβ or PPARγ, and increased the expression of TNF-α and IL-1β in Gingival fibroblasts, gingival epithelial cells and splenocytes from WT mice. Gingival mRNA levels of PPARα were significantly decreased in experimental periodontitis in WT mice. The bone loss of PPARα KO mice in experimental periodontitis was significantly higher than WT mice and was not reduced by fenofibrate treatment. Gingival TNFα protein expressions were significantly increased by P. gingivalis associated ligation and decreased by fenofibrate treatment in WT mice but not in PPARα KO mice. CONCLUSION This study suggests that PPARα plays an essential role in periodontitis.
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Affiliation(s)
- Ying Chen
- The Forsyth Institute, Department of Immunology and Infectious Diseases, Cambridge, United States
| | - Zheqing Jiang
- The Forsyth Institute, Department of Immunology and Infectious Diseases, Cambridge, United States
| | - Ana Keohane
- Boston University Henry M. Goldman School of Dental Medicine, Department of General Dentistry, Boston, United States
| | - Yang Hu
- The Forsyth Institute, Department of Immunology and Infectious Diseases, Cambridge, United States
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7
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Chen Y, Hu Y. Therapeutic potential of PPARα agonist in ligature-induced experimental periodontitis. J Appl Oral Sci 2022; 30:e20210648. [PMID: 35293424 PMCID: PMC8957283 DOI: 10.1590/1678-7757-2021-0648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/31/2022] [Indexed: 02/18/2023] Open
Abstract
Inflammation-related immune responses and bone metabolism lead to extensive tooth loss in periodontitis.
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8
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Kuiper JR, Braun JM, Calafat AM, Lanphear BP, Cecil KM, Chen A, Xu Y, Yolton K, Kalkwarf HJ, Buckley JP. Associations of pregnancy phthalate concentrations and their mixture with early adolescent bone mineral content and density: The Health Outcomes and Measures of the Environment (HOME) study. Bone 2022; 154:116251. [PMID: 34740813 PMCID: PMC8671261 DOI: 10.1016/j.bone.2021.116251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/22/2021] [Accepted: 10/29/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND The developing fetus may be particularly susceptibility to environmental osteotoxicants, but studies of pregnancy phthalate exposures and childhood bone health are scarce. OBJECTIVES To examine relations of pregnancy phthalate exposure biomarkers with early adolescent bone mineral density (BMD) and bone mineral content (BMC) in a prospective birth cohort. METHODS We used data from 223 pregnant mothers and their children enrolled in a Cincinnati, OH area cohort from 2003 to 2006. We quantified monoethyl phthalate (MEP), monoisobutyl phthalate, monobutyl phthalate, monobenzyl phthalate, mono-(3-carboxypropyl) phthalate (MCPP), and four metabolites of di-2-ethylhexyl phthalate in maternal urine collected at 16 and 26 weeks gestation, and calculated the average of creatinine-standardized concentrations. Using dual x-ray absorptiometry measures at age 12 years, we calculated BMD and BMC Z-scores for six skeletal sites. In overall and sex-stratified models, we estimated covariate-adjusted associations per 2-fold increase in phthalate biomarker concentrations using linear regression, and estimated joint effects of the phthalate biomarkers mixture using Bayesian kernel machine regression (BKMR) and quantile g-computation. RESULTS In single phthalate models, several biomarkers were positively associated with BMC and BMD. For example, each doubling of MEP and MCPP, 1/3rd distal radius BMD Z-score increased by 0.09 (95% CI: 0.01, 0.17) and 0.16 (95% CI: 0.01, 0.31), respectively. For phthalate mixtures, associations were generally U-shaped among males and positive-linear among females, using both statistical methods. Mixture associations were strongest with forearm sites: in BKMR models, increasing all biomarkers from the 50th to 90th percentile was associated with a 0.64 (95% CI: 0.01, 1.28) greater 1/3rd distal radius BMD Z-score in males, and a 0.49 (95% CI: -0.13, 1.10) greater ultradistal radius BMD Z-score in females. DISCUSSION In this study, phthalate exposures during gestation were associated with increased BMD Z-scores in early adolescence, though further research is needed to determine implications for long-term skeletal health.
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Affiliation(s)
- Jordan R Kuiper
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Joseph M Braun
- Department of Epidemiology, Brown University, Providence, RI, USA
| | - Antonia M Calafat
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Bruce P Lanphear
- Faculty of Health Sciences, Simon Fraser University, Vancouver, BC, Canada
| | - Kim M Cecil
- Department of Radiology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA; Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Aimin Chen
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA, USA
| | - Yingying Xu
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kimberly Yolton
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Heidi J Kalkwarf
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jessie P Buckley
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
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Role of K + and Ca 2+-Permeable Channels in Osteoblast Functions. Int J Mol Sci 2021; 22:ijms221910459. [PMID: 34638799 PMCID: PMC8509041 DOI: 10.3390/ijms221910459] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 09/23/2021] [Accepted: 09/24/2021] [Indexed: 12/20/2022] Open
Abstract
Bone-forming cells or osteoblasts play an important role in bone modeling and remodeling processes. Osteoblast differentiation or osteoblastogenesis is orchestrated by multiple intracellular signaling pathways (e.g., bone morphogenetic proteins (BMP) and Wnt signaling pathways) and is modulated by the extracellular environment (e.g., parathyroid hormone (PTH), vitamin D, transforming growth factor β (TGF-β), and integrins). The regulation of bone homeostasis depends on the proper differentiation and function of osteoblast lineage cells from osteogenic precursors to osteocytes. Intracellular Ca2+ signaling relies on the control of numerous processes in osteoblast lineage cells, including cell growth, differentiation, migration, and gene expression. In addition, hyperpolarization via the activation of K+ channels indirectly promotes Ca2+ signaling in osteoblast lineage cells. An improved understanding of the fundamental physiological and pathophysiological processes in bone homeostasis requires detailed investigations of osteoblast lineage cells. This review summarizes the current knowledge on the functional impacts of K+ channels and Ca2+-permeable channels, which critically regulate Ca2+ signaling in osteoblast lineage cells to maintain bone homeostasis.
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10
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Gholami A, Dabbaghmanesh MH, Ghasemi Y, Talezadeh P, Koohpeyma F, Montazeri-Najafabady N. Probiotics ameliorate pioglitazone-associated bone loss in diabetic rats. Diabetol Metab Syndr 2020. [DOI: 10.1186/s13098-020-00587-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Abstract
Background
Pioglitazone, as a PPAR gamma agonist, is used for the management of type 2 diabetes mellitus. Nevertheless, evidence showed that the therapeutic modulation of PPAR gamma activity using pioglitazone might be linked with bone mass reduction and fracture risk in type 2 diabetes mellitus patients. The objective of the current research was to inspect the preventive role of some types of probiotic strains, including (Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus casei, Bifidobacterium longum, and Bacillus coagulans) against pioglitazone-induced bone loss.
Methods
Streptozotocin (60 mg/kg) was administered for diabetes induction. Diabetic rats were fed orally with pioglitazone (300 mg/kg) and probiotics (1 × 109 CFU/ml/day) alone and in combination for four weeks. Dual-energy X-ray absorptiometry (DXA) was used to assess BMD, BMC, and area of the femur, spine, and tibia at the end of the experiment. Serum glucose, serum calcium (Ca), alkaline phosphatase (ALP), phosphorus (P), Blood urea nitrogen (BUN), creatinine, and urine calcium were also analyzed.
Results
Administration of pioglitazone and probiotics alone and, in combination, significantly reduced elevated blood glucose. Pioglitazone treatment significantly increased urinary calcium and BUN and decreased ALP and creatinine. Co-treatment of probiotics with pioglitazone significantly decreased urinary calcium, creatinine, and ALP. Pioglitazone showed detrimental effects on femur-BMD, whereas treatment with probiotics remarkably ameliorated these effects. Among the tested probiotics, Bifidobacterium longum displayed the best protective effects on pioglitazone-induced bone loss in diabetic rats.
Conclusion
This study suggests probiotic supplementation in diabetic patients on pioglitazone regime could be considering as an excellent strategy to ameliorate bone loss induced by pioglitazone.
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11
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Ewendt F, Hirche F, Feger M, Föller M. Peroxisome proliferator-activated receptor α (PPARα)-dependent regulation of fibroblast growth factor 23 (FGF23). Pflugers Arch 2020; 472:503-511. [PMID: 32189072 DOI: 10.1007/s00424-020-02363-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/04/2020] [Accepted: 03/05/2020] [Indexed: 10/24/2022]
Abstract
Bone cells secrete fibroblast growth factor 23 (FGF23), a hormone that inhibits the synthesis of active vitamin D (1,25(OH)2D3) and induces phosphate excretion in the kidney. In addition, it exerts paracrine effects on other cells including hepatocytes, cardiomyocytes, and immune cells. The production of FGF23 is controlled by different factors including parathyroid hormone, 1,25(OH)2D3, alimentary phosphate, insulin, inflammation, and AMP-dependent kinase (AMPK) regulation of store-operated Ca2+ entry (SOCE). Peroxisome proliferator-activated receptor α (PPARα) is a transcription factor with anti-inflammatory properties regulating lipid metabolism. Fibrates, PPARα agonists, are used in the treatment of dyslipidemia and activate AMPK. Here, we tested whether PPARα is a regulator of FGF23. Fgf23 gene expression was analyzed in UMR106 rat osteoblast-like cells by qRT-PCR, AMPK phosphorylation by Western blotting, and SOCE assessed by fluorescence optics. PPARα agonists fenofibrate and WY-14643 suppressed, whereas PPARα antagonist GW6471 and siRNA-mediated knockdown of PPARα induced Fgf23 gene expression. Fenofibrate induced AMPK activity in UMR106 cells and lowered SOCE. AMPK inhibitor compound C abrogated the PPARα effect on FGF23 in large part. Silencing of Orai-1 resulted in failure of PPARα to significantly influence Fgf23 expression. Taken together, PPARα is a potent regulator of FGF23. PPARα agonists down-regulate FGF23 formation at least in part through AMPK-mediated suppression of SOCE.
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Affiliation(s)
- Franz Ewendt
- Institute of Agricultural and Nutritional Science, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Frank Hirche
- Institute of Agricultural and Nutritional Science, Martin Luther University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Martina Feger
- Department of Physiology, University of Hohenheim, Garbenstraße 30, 70599, Stuttgart, Germany
| | - Michael Föller
- Department of Physiology, University of Hohenheim, Garbenstraße 30, 70599, Stuttgart, Germany.
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12
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Lysne V, Bjørndal B, Grinna ML, Midttun Ø, Ueland PM, Berge RK, Dierkes J, Nygård O, Strand E. Short-term treatment with a peroxisome proliferator-activated receptor α agonist influences plasma one-carbon metabolites and B-vitamin status in rats. PLoS One 2019; 14:e0226069. [PMID: 31805132 PMCID: PMC6894826 DOI: 10.1371/journal.pone.0226069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/18/2019] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Peroxisome proliferator-activated receptors (PPARs) have been suggested to be involved in the regulation of one-carbon metabolism. Previously we have reported effects on plasma concentrations of metabolites along these pathways as well as markers of B-vitamin status in rats following treatment with a pan-PPAR agonist. Here we aimed to investigate the effect on these metabolites after specific activation of the PPARα and PPARγ subtypes. METHODS For a period of 12 days, Male Wistar rats (n = 20) were randomly allocated to receive treatment with the PPARα agonist WY-14.643 (n = 6), the PPARγ agonist rosiglitazone (n = 6) or placebo (n = 8). The animals were sacrificed under fasting conditions, and plasma concentration of metabolites were determined. Group differences were assessed by one-way ANOVA, and planned comparisons were performed for both active treatment groups towards the control group. RESULTS Treatment with a PPARα agonist was associated with increased plasma concentrations of most biomarkers, with the most pronounced differences observed for betaine, dimethylglycine, glycine, nicotinamide, methylnicotinamide, pyridoxal and methylmalonic acid. Lower levels were observed for flavin mononucleotide. Fewer associations were observed after treatment with a PPARγ agonist, and the most notable was increased plasma serine. CONCLUSION Treatment with a PPARα agonist influenced plasma concentration of one-carbon metabolites and markers of B-vitamin status. This confirms previous findings, suggesting specific involvement of PPARα in the regulation of these metabolic pathways as well as the status of closely related B-vitamins.
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Affiliation(s)
- Vegard Lysne
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
- * E-mail:
| | - Bodil Bjørndal
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | | | | | - Per Magne Ueland
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Bevital A/S, Bergen, Norway
| | - Rolf Kristian Berge
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
| | - Jutta Dierkes
- Centre for Nutrition, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Mohn Nutrition Research Laboratory, Centre for Nutrition, University of Bergen, Bergen, Norway
- Laboratory Medicine and Pathology, Haukeland University Hospital, Bergen, Norway
| | - Ottar Nygård
- Centre for Nutrition, Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
- Mohn Nutrition Research Laboratory, Centre for Nutrition, University of Bergen, Bergen, Norway
| | - Elin Strand
- Department of Clinical Science, University of Bergen, Bergen, Norway
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13
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Pinchbeck JL, Moxon JV, Rowbotham SE, Bourke M, Lazzaroni S, Morton SK, Matthews EO, Hendy K, Jones RE, Bourke B, Jaeggi R, Favot D, Quigley F, Jenkins JS, Reid CM, Velu R, Golledge J. Randomized Placebo-Controlled Trial Assessing the Effect of 24-Week Fenofibrate Therapy on Circulating Markers of Abdominal Aortic Aneurysm: Outcomes From the FAME -2 Trial. J Am Heart Assoc 2019; 7:e009866. [PMID: 30371299 PMCID: PMC6404864 DOI: 10.1161/jaha.118.009866] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Background There is no drug therapy for abdominal aortic aneurysm (AAA). FAME‐2 (Fenofibrate in the Management of Abdominal Aortic Aneurysm 2) was a placebo‐controlled randomized trial designed to assess whether administration of 145 mg of fenofibrate/d for 24 weeks favorably modified circulating markers of AAA. Methods and Results Patients with AAAs measuring 35 to 49 mm and no contraindication were randomized to fenofibrate or identical placebo. The primary outcome measures were the differences in serum osteopontin and kallistatin concentrations between groups. Secondary analyses compared changes in the circulating concentration of AAA‐associated proteins, and AAA growth, between groups using multivariable linear mixed‐effects modeling. A total of 140 patients were randomized to receive fenofibrate (n=70) or placebo (n=70). By the end of the study 3 (2.1%) patients were lost to follow‐up and 18 (12.9%) patients had ceased trial medication. A total of 85% of randomized patients took ≥80% of allocated tablets and were deemed to have complied with the medication regimen. Patients’ allocated fenofibrate had expected reductions in serum triglycerides and estimated glomerular filtration rate, and increases in serum homocysteine. No differences in serum osteopontin, kallistatin, or AAA growth were observed between groups. Conclusions Administering 145 mg/d of fenofibrate for 24 weeks did not significantly reduce serum concentrations of osteopontin and kallistatin concentrations, or rates of AAA growth in this trial. The findings do not support the likely benefit of fenofibrate as a treatment for patients with small AAAs. Clinical Trial Registration URL: http://www.anzctr.org.au. Unique identifier: ACTRN12613001039774.
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Affiliation(s)
- Jenna L Pinchbeck
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Joseph V Moxon
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,2 The Australian Institute of Tropical Health and Medicine James Cook University Townsville Queensland Australia
| | - Sophie E Rowbotham
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,3 Department of Vascular Surgery The Royal Brisbane and Women's Hospital Herston Queensland Australia.,4 School of Medicine The University of Queensland Herston Queensland Australia
| | - Michael Bourke
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,5 Gosford Vascular Services Gosford New South Wales Australia
| | - Sharon Lazzaroni
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Susan K Morton
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Evan O Matthews
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Kerolos Hendy
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Rhondda E Jones
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,2 The Australian Institute of Tropical Health and Medicine James Cook University Townsville Queensland Australia
| | - Bernie Bourke
- 5 Gosford Vascular Services Gosford New South Wales Australia
| | - Rene Jaeggi
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia
| | - Danella Favot
- 3 Department of Vascular Surgery The Royal Brisbane and Women's Hospital Herston Queensland Australia
| | - Frank Quigley
- 6 Department of Vascular and Endovascular Surgery Mater Hospital Townsville Queensland Australia
| | - Jason S Jenkins
- 3 Department of Vascular Surgery The Royal Brisbane and Women's Hospital Herston Queensland Australia
| | - Christopher M Reid
- 7 School of Public Health and Preventative Medicine Monash University Melbourne Victoria Australia.,8 School of Public Health Curtin University Perth Western Australia Australia
| | - Ramesh Velu
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,9 Department of Vascular and Endovascular Surgery The Townsville Hospital Townsville Queensland Australia
| | - Jonathan Golledge
- 1 The Queensland Research Centre for Peripheral Vascular Disease College of Medicine and Dentistry James Cook University Townsville Queensland Australia.,2 The Australian Institute of Tropical Health and Medicine James Cook University Townsville Queensland Australia.,6 Department of Vascular and Endovascular Surgery Mater Hospital Townsville Queensland Australia.,9 Department of Vascular and Endovascular Surgery The Townsville Hospital Townsville Queensland Australia
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14
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Lotz EM, Berger MB, Schwartz Z, Boyan BD. Regulation of osteoclasts by osteoblast lineage cells depends on titanium implant surface properties. Acta Biomater 2018; 68:296-307. [PMID: 29292169 PMCID: PMC5803380 DOI: 10.1016/j.actbio.2017.12.039] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/29/2017] [Accepted: 12/22/2017] [Indexed: 01/16/2023]
Abstract
A critical stage during osseointegration of a titanium (Ti) implant is primary bone remodeling, which involves cross talk among osteoclast precursors, osteoclasts, mesenchymal stem cells (MSCs), and osteoblasts. This phase couples the processes of bone formation and resorption. During remodeling, osteoclasts produce factors capable of regulating MSC migration and osteogenesis. Furthermore, they degrade primary bone, creating a foundation with a specific chemistry, stiffness, and morphology for osteoblasts to synthesize and calcify their matrix. MSCs and osteoblasts receiving cues from the implant surface produce factors capable of regulating osteoclasts in order to promote net new bone formation. The purpose of this study was to determine the effects Ti implant surfaces have on bone remodeling. Human MSCs and normal human osteoblasts (NHOsts) were cultured separately on 15 mm grade 2 smooth PT, hydrophobic-microrough SLA, hydrophilic-microrough Ti (mSLA) (Institut Straumann AG, Basel, Switzerland), or tissue culture polystyrene (TCPS). After 7d, conditioned media from surface cultures were used to treat human osteoclasts for 2d. Activity was measured by fluorescence of released collagen followed by mRNA quantification. This study demonstrates that MSC and NHOst cultures are able to suppress osteoclast activity in a surface dependent manner and osteoclast mRNA levels are selectively regulated by surface treatments. The substrate-dependent regulatory effect was mitigated when MSCs were silenced for integrin subunits and when conditioned media were denatured. These results indicate that MSCs and NHOsts regulate at least two aspects of remodeling: reduced fusion of new osteoclasts and reduced activity of existing osteoclasts. STATEMENT OF SIGNIFICANCE In this study, we developed a novel in vitro model to study how microstructured and hydrophilic titanium implants impact bone remodeling for dental and orthopaedic applications. Our approach intersects biomaterials and systems physiology, revealing for the first time that implant surface properties are capable of regulating the communication among the cells involved in remodeling of primary bone during osseointegration. We believe that the basic research presented in our manuscript will provide important knowledge in our understanding of factors that impact implant success. Furthermore, it provides a solid foundation for the development of materials that enable rapid osseointegration and earlier loading times for implants in bone that has been compromised by trauma or disease.
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Affiliation(s)
- Ethan M Lotz
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Michael B Berger
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Zvi Schwartz
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA; Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Barbara D Boyan
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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15
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Haugen S, He J, Sundaresan A, Stunes AK, Aasarød KM, Tiainen H, Syversen U, Skallerud B, Reseland JE. Adiponectin Reduces Bone Stiffness: Verified in a Three-Dimensional Artificial Human Bone Model In Vitro. Front Endocrinol (Lausanne) 2018; 9:236. [PMID: 29867768 PMCID: PMC5960720 DOI: 10.3389/fendo.2018.00236] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/25/2018] [Indexed: 01/31/2023] Open
Abstract
Primary human osteoblasts and osteoclasts incubated in a rotating coculture system without any scaffolding material, form bone-like tissue that may be used to evaluate effects of various compounds on mechanical strength. Circulating adiponectin has been found to be negatively associated with BMD and strength and was therefore assessed in this system. Osteospheres of human osteoblasts and osteoclasts were generated with and without adiponectin. The osteospheres were scanned using micro-computed tomography, the mechanical properties were tested by flat punch compression using nanoindentation equipment, and the cellular morphology characterized by microscopy. The association between autologously produced adiponectin and biomechanical properties was further evaluated by quantitation of adiponectin levels using quantitative polymerase chain reaction (qPCR) and immunoassays, and identification of stiffness by bending test of rat femurs. The molecular mechanisms were examined in vitro using human bone cells. Mechanical testing revealed that adiponectin induced a more compliant osteosphere compared with control. The osteospheres had a round, lobulated appearance with morphologically different areas; inner regions containing few cells embedded in a bone-like material surrounded by an external area with a higher cell quantity. The expression of adiponectin was found to correlate positively to ultimate bending moment and ultimate energy absorption and deflection, on the other hand, it correlated negatively to bending stiffness, indicating autocrine and/or paracrine effects of adiponectin in bone. Adiponectin enhanced proliferation and expression of collagen, leptin, and tumor necrosis factor-alpha in osteoblasts and stimulated proliferation, but not the functional activity of osteoclasts. Our results indicate that both administration of adiponectin during osteosphere production and in situ elevated levels of adiponectin in rat femurs, reduced stiffness of the bone tissues. An increase in undifferentiated cells and extracellular matrix proteins, such as collagen, may explain the reduced bone stiffness seen in the osteospheres treated with adiponectin.
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Affiliation(s)
- Sigrid Haugen
- Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, Oslo, Norway
| | - Jianying He
- Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Alamelu Sundaresan
- Department of Biology, Texas Southern University, Houston, TX, United States
| | - Astrid Kamilla Stunes
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- St. Olav’s University Hospital, Trondheim, Norway
| | - Kristin Matre Aasarød
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- St. Olav’s University Hospital, Trondheim, Norway
| | - Hanna Tiainen
- Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, Oslo, Norway
| | - Unni Syversen
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Endocrinology, St. Olav’s University Hospital, Trondheim, Norway
| | - Bjørn Skallerud
- Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Janne Elin Reseland
- Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, Oslo, Norway
- *Correspondence: Janne Elin Reseland,
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16
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Adil M, Mansoori MN, Singh D, Kandhare AD, Sharma M. Pioglitazone-induced bone loss in diabetic rats and its amelioration by berberine: A portrait of molecular crosstalk. Biomed Pharmacother 2017; 94:1010-1019. [DOI: 10.1016/j.biopha.2017.08.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/30/2017] [Accepted: 08/01/2017] [Indexed: 12/24/2022] Open
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17
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Davidson MA, Mattison DR, Azoulay L, Krewski D. Thiazolidinedione drugs in the treatment of type 2 diabetes mellitus: past, present and future. Crit Rev Toxicol 2017; 48:52-108. [PMID: 28816105 DOI: 10.1080/10408444.2017.1351420] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Thiazolidinedione (TZD) drugs used in the treatment of type 2 diabetes mellitus (T2DM) have proven effective in improving insulin sensitivity, hyperglycemia, and lipid metabolism. Though well tolerated by some patients, their mechanism of action as ligands of peroxisome proliferator-activated receptors (PPARs) results in the activation of several pathways in addition to those responsible for glycemic control and lipid homeostasis. These pathways, which include those related to inflammation, bone formation, and cell proliferation, may lead to adverse health outcomes. As treatment with TZDs has been associated with adverse hepatic, cardiovascular, osteological, and carcinogenic events in some studies, the role of TZDs in the treatment of T2DM continues to be debated. At the same time, new therapeutic roles for TZDs are being investigated, with new forms and isoforms currently in the pre-clinical phase for use in the prevention and treatment of some cancers, inflammatory diseases, and other conditions. The aims of this review are to provide an overview of the mechanism(s) of action of TZDs, a review of their safety for use in the treatment of T2DM, and a perspective on their current and future therapeutic roles.
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Affiliation(s)
- Melissa A Davidson
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada
| | - Donald R Mattison
- b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada
| | - Laurent Azoulay
- d Center for Clinical Epidemiology , Lady Davis Research Institute, Jewish General Hospital , Montreal , Canada.,e Department of Oncology , McGill University , Montreal , Canada
| | - Daniel Krewski
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada.,f Faculty of Medicine , University of Ottawa , Ottawa , Canada
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18
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Gong K, Qu B, Wang C, Zhou J, Liao D, Zheng W, Pan X. Peroxisome Proliferator-Activated Receptor α Facilitates Osteogenic Differentiation in MC3T3-E1 Cells via the Sirtuin 1-Dependent Signaling Pathway. Mol Cells 2017; 40:393-400. [PMID: 28614912 PMCID: PMC5523015 DOI: 10.14348/molcells.2017.0018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/20/2017] [Accepted: 05/03/2017] [Indexed: 11/27/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by lack of insulin and high glucose levels. T2DM can cause bone loss and fracture, thus leading to diabetic osteoporosis. Promoting osteogenic differentiation of osteoblasts may effectively treat diabetic osteoporosis. We previously reported that Sirtuin 1 (Sirt1), a NAD+-dependent deacetylase, promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor (PPAR) γ. We also found that miR-132 regulates osteogenic differentiation by downregulating Sirt1 in a PPARβ/δ-dependent manner. The ligand-activated transcription factor, PPARα, is another isotype of the peroxisome proliferator-activated receptor family that helps maintain bone homeostasis and promot bone formation. Whether the regulatory role of PPARα in osteogenic differentiation is mediated via Sirt1 remains unclear. In the present study, we aimed to determine this role and the underlying mechanism by using high glucose (HG) and free fatty acids (FFA) to mimic T2DM in MC3T3-E1 cells. The results showed that HG-FFA significantly inhibited expression of PPARα, Sirt1 and osteogenic differentiation, but these effects were markedly reversed by PPARα overexpression. Moreover, siSirt1 attenuated the positive effects of PPARα on osteogenic differentiation, suggesting that PPARα promotes osteogenic differentiation in a Sirt1-dependent manner. Luciferase activity assay confirmed interactions between PPARα and Sirt1. These findings indicate that PPARα promotes osteogenic differentiation via the Sirt1-dependent signaling pathway.
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Affiliation(s)
- Kai Gong
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Bo Qu
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Cairu Wang
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Jingsong Zhou
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Dongfa Liao
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Wei Zheng
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
| | - Xianming Pan
- Department of Orthopaedics, Chengdu Military General Hospital, No. 270 Rongdu Road, Chengdu, Sichuan 610083,
China
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19
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Lindsey RC, Mohan S. Thyroid hormone acting via TRβ induces expression of browning genes in mouse bone marrow adipose tissue. Endocrine 2017; 56:109-120. [PMID: 28229360 PMCID: PMC8745377 DOI: 10.1007/s12020-017-1265-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 02/10/2017] [Indexed: 12/17/2022]
Abstract
PURPOSE Mutant hypothyroid mouse models have recently shown that thyroid hormone is critical for skeletal development during an important prepubertal growth period. Additionally, thyroid hormone negatively regulates total body fat, consistent with the well-established effects of thyroid hormone on energy and fat metabolism. Since bone marrow mesenchymal stromal cells differentiate into both adipocytes and osteoblasts and a relationship between bone marrow adipogenesis and osteogenesis has been predicted, we hypothesized thyroid hormone deficiency during the postnatal growth period increases marrow adiposity in mice. METHODS Marrow adiposity in TH-deficient (Tshr -/-) mice treated with T3/T4, TH receptor β-specific agonist GC-1, or vehicle control was evaluated via dual-energy X-ray absorptiometry and osmium micro-computed tomography. To further examine the mechanism for thyroid hormone regulation of marrow adiposity, we used real-time RT-PCR to measure the effects of thyroid hormone on adipocyte differentiation markers in primary mouse bone marrow mesenchymal stromal cells and two mouse cell lines in vitro and in Tshr -/- mice in vivo. RESULTS Marrow adiposity increased >20% (P < 0.01) in Tshr -/- mice at 3 weeks of age, and treatment with T3/T4 when serum thyroid hormone normally increases (day 5-14) rescued this phenotype. Furthermore, GC-1 rescued this phenotype equally well, suggesting this thyroid hormone effect is in part mediated via TRβ signaling. Treatment of bone marrow mesenchymal stromal or ST2 cells with T3 or GC-1 significantly increased expression of several brown/beige fat markers. Moreover, injection of T3/T4 increased browning-specific markers in white fat of Tshr -/- mice. CONCLUSIONS These data suggest that thyroid hormone regulation of marrow adiposity is mediated at least in part via activation of TRβ signaling.
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Affiliation(s)
- Richard C Lindsey
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Center for Health Disparities and Molecular Medicine, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA.
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
- Center for Health Disparities and Molecular Medicine, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
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20
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Lin CH, Wu JB, Jian JY, Shih CC. (-)-Epicatechin-3-O-β-D-allopyranoside from Davallia formosana prevents diabetes and dyslipidemia in streptozotocin-induced diabetic mice. PLoS One 2017; 12:e0173984. [PMID: 28333970 PMCID: PMC5363832 DOI: 10.1371/journal.pone.0173984] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 03/01/2017] [Indexed: 12/20/2022] Open
Abstract
The objective of this study was to evaluate the effects and molecular mechanism of (-)-epicatechin-3-O-β-D-allopyranoside from Davallia formosana (BB) (also known as Gu-Sui-Bu) on type 1 diabetes mellitus and dyslipidemia in streptozotocin (STZ)-induced diabetic mice. This plant was demonstrated to display antioxidant activities and possess polyphenol contents. Diabetic mice were randomly divided into six groups and were given daily oral gavage doses of either BB (at three dosage levels), metformin (Metf) (at 0.3 g/kg body weight), fenofibrate (Feno) (at 0.25 g/kg body weight) or vehicle (distilled water) and a group of control (CON) mice were gavaged with vehicle over a period of 4 weeks. Treatment with BB led to reduced levels of blood glucose, HbA1C, triglycerides and leptin and to increased levels of insulin and adiponectin compared with the vehicle-treated STZ group. The diabetic islets showed retraction from their classic round-shaped as compared with the control islets. The BB-treated groups (at middle and high dosages) showed improvement in islets size and number of Langerhans islet cells. The membrane levels of skeletal muscular glucose transporter 4 (GLUT4) were significantly higher in BB-treated mice. This resulted in a net glucose lowering effect among BB-treated mice. Moreover, BB enhanced the expression of skeletal muscle phospho-AMPK in treated mice. BB-treated mice increased expression of fatty acid oxidation enzymes, including peroxisome proliferator-activated receptor α (PPARα) and mRNA levels of carnitine palmitoyl transferase Ia (CPT1a). These mice also expressed lower levels of lipogenic genes such as fatty acid synthase (FAS), as well as lower mRNA levels of sterol regulatory element binding protein 1c (SREBP1c) and liver adipocyte fatty acid binding protein 2 (aP2). This resulted in a reduction in plasma triglyceride levels. BB-treated mice also expressed lower levels of PPARγ and FAS protein. This led to reduced adipogenesis, fatty acid synthesis and lipid accumulation within adipose tissue, and consequently, to lower triglyceride levels in liver, blood, and adipose tissue. Moreover, BB treatment not only displayed the activation Akt in liver tissue and skeletal muscle, but also in C2C12 myotube to cause an increase in phosphorylation of Akt in the absence of insulin. These results demonstrated that BB act as an activator of AMPK and /or regulation of insulin pathway (Akt), and the antioxidant activity within the pancreas. Therefore, BB treatment ameliorated the diabetic and dyslipidemic state in STZ-induced diabetic mice.
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Affiliation(s)
- Cheng-Hsiu Lin
- Department of Internal Medicine, Fengyuan Hospital, Ministry of Health and Welfare, Fengyuan District, Taichung City, Taiwan
| | - Jin-Bin Wu
- Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung City, Taiwan
| | - Jia-Ying Jian
- Graduate Institute of Biotechnology and Biomedical Engineering, College of Health Science, Central Taiwan University of Science and Technology, Taichung City, Taiwan
| | - Chun-Ching Shih
- Graduate Institute of Biotechnology and Biomedical Engineering, College of Health Science, Central Taiwan University of Science and Technology, Taichung City, Taiwan
- * E-mail:
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21
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Stechschulte LA, Czernik PJ, Rotter ZC, Tausif FN, Corzo CA, Marciano DP, Asteian A, Zheng J, Bruning JB, Kamenecka TM, Rosen CJ, Griffin PR, Lecka-Czernik B. PPARG Post-translational Modifications Regulate Bone Formation and Bone Resorption. EBioMedicine 2016; 10:174-84. [PMID: 27422345 PMCID: PMC5006645 DOI: 10.1016/j.ebiom.2016.06.040] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 11/24/2022] Open
Abstract
The peroxisome proliferator-activated receptor gamma (PPARγ) regulates osteoblast and osteoclast differentiation, and is the molecular target of thiazolidinediones (TZDs), insulin sensitizers that enhance glucose utilization and adipocyte differentiation. However, clinical use of TZDs has been limited by side effects including a higher risk of fractures and bone loss. Here we demonstrate that the same post-translational modifications at S112 and S273, which influence PPARγ pro-adipocytic and insulin sensitizing activities, also determine PPARγ osteoblastic (pS112) and osteoclastic (pS273) activities. Treatment of either hyperglycemic or normoglycemic animals with SR10171, an inverse agonist that blocks pS273 but not pS112, increased trabecular and cortical bone while normalizing metabolic parameters. Additionally, SR10171 treatment modulated osteocyte, osteoblast, and osteoclast activities, and decreased marrow adiposity. These data demonstrate that regulation of bone mass and energy metabolism shares similar mechanisms suggesting that one pharmacologic agent could be developed to treat both diabetes and metabolic bone disease. PPARγ S273 regulates osteoclast differentiation and insulin sensitivity PPARγ S112 regulates osteoblast and adipocyte differentiation PPARγ and PPARα regulate osteocyte activities of bone formation and turnover SR10171, a PPARγ inverse agonist and PPARα weak agonist, is anabolic for bone
Diabetes is a condition with compromised energy balance and is associated with bone fractures. Some treatment options for diabetes sensitize the patient to insulin via targeting the transcription factor PPARγ. PPARγ is also key regulator of bone formation and bone resorption. Anti-diabetic drugs TZDs target PPARγ protein and this leads to bone loss and increase in fractures in postmenopausal women. Bone mass and energy metabolism share similar regulating pathways, and here we demonstrate a new class of insulin sensitizers that is a selective modulator of PPARγ activity; resulting in a pharmacologic agent that can be beneficial for both diabetes and metabolic bone disease.
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Affiliation(s)
- L A Stechschulte
- Dept. Orthopaedic Surgery, University of Toledo Health Science Campus, Toledo, OH 43614, United States; Center for Diabetes and Endocrine Research, University of Toledo Health Science Campus, Toledo, OH 43614, United States
| | - P J Czernik
- Dept. Orthopaedic Surgery, University of Toledo Health Science Campus, Toledo, OH 43614, United States
| | - Z C Rotter
- Dept. Orthopaedic Surgery, University of Toledo Health Science Campus, Toledo, OH 43614, United States
| | - F N Tausif
- Dept. Orthopaedic Surgery, University of Toledo Health Science Campus, Toledo, OH 43614, United States
| | - C A Corzo
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States
| | - D P Marciano
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States
| | - A Asteian
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States
| | - J Zheng
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States
| | - J B Bruning
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - T M Kamenecka
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States
| | - C J Rosen
- Maine Medical Center Research Institute, Scarborough, ME 04074, United States
| | - P R Griffin
- Dept. Molecular Therapeutics, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, United States.
| | - B Lecka-Czernik
- Dept. Orthopaedic Surgery, University of Toledo Health Science Campus, Toledo, OH 43614, United States; Center for Diabetes and Endocrine Research, University of Toledo Health Science Campus, Toledo, OH 43614, United States; Dept. Physiology and Pharmacology, University of Toledo Health Science Campus, Toledo, OH 43614, United States.
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22
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Lysne V, Strand E, Svingen GFT, Bjørndal B, Pedersen ER, Midttun Ø, Olsen T, Ueland PM, Berge RK, Nygård O. Peroxisome Proliferator-Activated Receptor Activation is Associated with Altered Plasma One-Carbon Metabolites and B-Vitamin Status in Rats. Nutrients 2016; 8:nu8010026. [PMID: 26742069 PMCID: PMC4728640 DOI: 10.3390/nu8010026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/18/2015] [Accepted: 12/28/2015] [Indexed: 12/16/2022] Open
Abstract
Plasma concentrations of metabolites along the choline oxidation pathway have been linked to increased risk of major lifestyle diseases, and peroxisome proliferator-activated receptors (PPARs) have been suggested to be involved in the regulation of key enzymes along this pathway. In this study, we investigated the effect of PPAR activation on circulating and urinary one-carbon metabolites as well as markers of B-vitamin status. Male Wistar rats (n = 20) received for 50 weeks either a high-fat control diet or a high-fat diet with tetradecylthioacetic acid (TTA), a modified fatty acid and pan-PPAR agonist with high affinity towards PPARα. Hepatic gene expression of PPARα, PPARβ/δ and the enzymes involved in the choline oxidation pathway were analyzed and concentrations of metabolites were analyzed in plasma and urine. TTA treatment altered most biomarkers, and the largest effect sizes were observed for plasma concentrations of dimethylglycine, nicotinamide, methylnicotinamide, methylmalonic acid and pyridoxal, which were all higher in the TTA group (all p < 0.01). Hepatic Pparα mRNA was increased after TTA treatment, but genes of the choline oxidation pathway were not affected. Long-term TTA treatment was associated with pronounced alterations on the plasma and urinary concentrations of metabolites related to one-carbon metabolism and B-vitamin status in rats.
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Affiliation(s)
- Vegard Lysne
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
| | - Elin Strand
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
| | - Gard F T Svingen
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
- Department of Heart Disease, Haukeland University Hospital, 5021 Bergen, Norway.
| | - Bodil Bjørndal
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
| | - Eva R Pedersen
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
- Department of Heart Disease, Haukeland University Hospital, 5021 Bergen, Norway.
| | | | - Thomas Olsen
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
| | - Per M Ueland
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
- Laboratory of Clinical Biochemistry, Haukeland University Hospital, 5021 Bergen, Norway.
| | - Rolf K Berge
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
- Department of Heart Disease, Haukeland University Hospital, 5021 Bergen, Norway.
| | - Ottar Nygård
- Department of Clinical Science, University of Bergen, 5020 Bergen, Norway.
- Department of Heart Disease, Haukeland University Hospital, 5021 Bergen, Norway.
- KG Jebsen Centre for Diabetes Research, University of Bergen, 5009 Bergen, Norway.
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23
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Qian G, Fan W, Ahlemeyer B, Karnati S, Baumgart-Vogt E. Peroxisomes in Different Skeletal Cell Types during Intramembranous and Endochondral Ossification and Their Regulation during Osteoblast Differentiation by Distinct Peroxisome Proliferator-Activated Receptors. PLoS One 2015; 10:e0143439. [PMID: 26630504 PMCID: PMC4668026 DOI: 10.1371/journal.pone.0143439] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 11/04/2015] [Indexed: 01/10/2023] Open
Abstract
Ossification defects leading to craniofacial dysmorphism or rhizomelia are typical phenotypes in patients and corresponding knockout mouse models with distinct peroxisomal disorders. Despite these obvious skeletal pathologies, to date no careful analysis exists on the distribution and function of peroxisomes in skeletal tissues and their alterations during ossification. Therefore, we analyzed the peroxisomal compartment in different cell types of mouse cartilage and bone as well as in primary cultures of calvarial osteoblasts. The peroxisome number and metabolism strongly increased in chondrocytes during endochondral ossification from the reserve to the hypertrophic zone, whereas in bone, metabolically active osteoblasts contained a higher numerical abundance of this organelle than osteocytes. The high abundance of peroxisomes in these skeletal cell types is reflected by high levels of Pex11β gene expression. During culture, calvarial pre-osteoblasts differentiated into secretory osteoblasts accompanied by peroxisome proliferation and increased levels of peroxisomal genes and proteins. Since many peroxisomal genes contain a PPAR-responsive element, we analyzed the gene expression of PPARɑ/ß/ɣ in calvarial osteoblasts and MC3T3-E1 cells, revealing higher levels for PPARß than for PPARɑ and PPARɣ. Treatment with different PPAR agonists and antagonists not only changed the peroxisomal compartment and associated gene expression, but also induced complex alterations of the gene expression patterns of the other PPAR family members. Studies in M3CT3-E1 cells showed that the PPARß agonist GW0742 activated the PPRE-mediated luciferase expression and up-regulated peroxisomal gene transcription (Pex11, Pex13, Pex14, Acox1 and Cat), whereas the PPARß antagonist GSK0660 led to repression of the PPRE and a decrease of the corresponding mRNA levels. In the same way, treatment of calvarial osteoblasts with GW0742 increased in peroxisome number and related gene expression and accelerated osteoblast differentiation. Taken together, our results suggest that PPARß regulates the numerical abundance and metabolic function of peroxisomes via Pex11ß in parallel to osteoblast differentiation.
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Affiliation(s)
- Guofeng Qian
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus-Liebig-University, Aulweg 123, 35385 Giessen, Germany
| | - Wei Fan
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus-Liebig-University, Aulweg 123, 35385 Giessen, Germany
| | - Barbara Ahlemeyer
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus-Liebig-University, Aulweg 123, 35385 Giessen, Germany
| | - Srikanth Karnati
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus-Liebig-University, Aulweg 123, 35385 Giessen, Germany
| | - Eveline Baumgart-Vogt
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus-Liebig-University, Aulweg 123, 35385 Giessen, Germany
- * E-mail:
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24
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Carson JA, Hardee JP, VanderVeen BN. The emerging role of skeletal muscle oxidative metabolism as a biological target and cellular regulator of cancer-induced muscle wasting. Semin Cell Dev Biol 2015; 54:53-67. [PMID: 26593326 DOI: 10.1016/j.semcdb.2015.11.005] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/12/2015] [Indexed: 12/17/2022]
Abstract
While skeletal muscle mass is an established primary outcome related to understanding cancer cachexia mechanisms, considerable gaps exist in our understanding of muscle biochemical and functional properties that have recognized roles in systemic health. Skeletal muscle quality is a classification beyond mass, and is aligned with muscle's metabolic capacity and substrate utilization flexibility. This supplies an additional role for the mitochondria in cancer-induced muscle wasting. While the historical assessment of mitochondria content and function during cancer-induced muscle loss was closely aligned with energy flux and wasting susceptibility, this understanding has expanded to link mitochondria dysfunction to cellular processes regulating myofiber wasting. The primary objective of this article is to highlight muscle mitochondria and oxidative metabolism as a biological target of cancer cachexia and also as a cellular regulator of cancer-induced muscle wasting. Initially, we examine the role of muscle metabolic phenotype and mitochondria content in cancer-induced wasting susceptibility. We then assess the evidence for cancer-induced regulation of skeletal muscle mitochondrial biogenesis, dynamics, mitophagy, and oxidative stress. In addition, we discuss environments associated with cancer cachexia that can impact the regulation of skeletal muscle oxidative metabolism. The article also examines the role of cytokine-mediated regulation of mitochondria function, followed by the potential role of cancer-induced hypogonadism. Lastly, a role for decreased muscle use in cancer-induced mitochondrial dysfunction is reviewed.
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Affiliation(s)
- James A Carson
- Integrative Muscle Biology Laboratory, Department of Exercise Science, University of South Carolina, 921 Assembly St., Columbia, SC, 29208, USA.
| | - Justin P Hardee
- Integrative Muscle Biology Laboratory, Department of Exercise Science, University of South Carolina, 921 Assembly St., Columbia, SC, 29208, USA
| | - Brandon N VanderVeen
- Integrative Muscle Biology Laboratory, Department of Exercise Science, University of South Carolina, 921 Assembly St., Columbia, SC, 29208, USA
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25
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Smith SY, Samadfam R, Chouinard L, Awori M, Bénardeau A, Bauss F, Guldberg RE, Sebokova E, Wright MB. Effects of pioglitazone and fenofibrate co-administration on bone biomechanics and histomorphometry in ovariectomized rats. J Bone Miner Metab 2015; 33:625-41. [PMID: 25534548 DOI: 10.1007/s00774-014-0632-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 09/02/2014] [Indexed: 01/31/2023]
Abstract
Pioglitazone, the peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist is an effective therapy for type 2 diabetes, but has been associated with increased risk for bone fracture. Preclinical studies suggest that PPAR-α agonists (e.g., fenofibrate) increase bone mineral density/content, although clinical data on bone effects of fibrates are lacking. We investigated the effects of pioglitazone (10 mg/kg/day) and fenofibrate (25 mg/kg/day) on bone strength and bone histomorphometric parameters in osteopenic ovariectomized (OVX) rats. An additional group of rats received a combination of pioglitazone + fenofibrate to mimic the effects of a dual PPAR-α/γ agonist. The study consisted of a 13-week treatment phase followed by a 6-week treatment-free recovery period. Pioglitazone significantly reduced biomechanical strength at the lumbar spine and femoral neck compared with rats administered fenofibrate. Co-treatment with pioglitazone + fenofibrate had no significant effect on bone strength in comparison with OVX vehicle controls. Histomorphometric analysis of the proximal tibia revealed that pioglitazone suppressed bone formation and increased bone resorption at both cancellous and cortical bone sites relative to OVX vehicle controls. In contrast, fenofibrate did not affect bone resorption and only slightly suppressed bone formation. Discontinuation of pioglitazone treatment, both in the monotherapy and in the combination therapy arms, resulted in restoration of bone formation and resorption rates, demonstrating reversibility of effects. The above data support the concept that dual activation of PPAR-γ and PPAR-α attenuates the negative effects of PPAR-γ agonism on bone strength.
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Affiliation(s)
| | | | | | | | - Agnes Bénardeau
- DTA Cardiovascular and Metabolism, pRED Pharma Research and Early Development, F. Hoffmann-La Roche AG, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Frieder Bauss
- Discovery Oncology, Pharmaceutical Research and Early Development (pRED), Roche Diagnostics GmbH, Penzberg, Germany
| | | | - Elena Sebokova
- DTA Cardiovascular and Metabolism, pRED Pharma Research and Early Development, F. Hoffmann-La Roche AG, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Matthew B Wright
- DTA Cardiovascular and Metabolism, pRED Pharma Research and Early Development, F. Hoffmann-La Roche AG, Grenzacherstrasse 124, 4070, Basel, Switzerland.
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26
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Carson JA, Manolagas SC. Effects of sex steroids on bones and muscles: Similarities, parallels, and putative interactions in health and disease. Bone 2015; 80:67-78. [PMID: 26453497 PMCID: PMC4600533 DOI: 10.1016/j.bone.2015.04.015] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/23/2015] [Accepted: 04/07/2015] [Indexed: 12/31/2022]
Abstract
Estrogens and androgens influence the growth and maintenance of bones and muscles and are responsible for their sexual dimorphism. A decline in their circulating levels leads to loss of mass and functional integrity in both tissues. In the article, we highlight the similarities of the molecular and cellular mechanisms of action of sex steroids in the two tissues; the commonality of a critical role of mechanical forces on tissue mass and function; emerging evidence for an interplay between mechanical forces and hormonal and growth factor signals in both bones and muscles; as well as the current state of evidence for or against a cross-talk between muscles and bone. In addition, we review evidence for the parallels in the development of osteoporosis and sarcopenia with advancing age and the potential common mechanisms responsible for the age-dependent involution of these two tissues. Lastly, we discuss the striking difference in the availability of several drug therapies for the prevention and treatment of osteoporosis, as compared to none for sarcopenia. This article is part of a Special Issue entitled "Muscle Bone Interactions".
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Affiliation(s)
- James A Carson
- Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208 USA
| | - Stavros C Manolagas
- Division of Endocrinology and Metabolism, Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences and the Central Arkansas Veterans Healthcare System, Little Rock, AR, USA.
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27
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Palermo A, D'Onofrio L, Eastell R, Schwartz AV, Pozzilli P, Napoli N. Oral anti-diabetic drugs and fracture risk, cut to the bone: safe or dangerous? A narrative review. Osteoporos Int 2015; 26:2073-89. [PMID: 25910746 DOI: 10.1007/s00198-015-3123-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/24/2015] [Indexed: 12/16/2022]
Abstract
Fracture risk is higher in older adults with type 2 diabetes and may be influenced by treatments for diabetes. Oral anti-diabetic drugs have different effects on bone metabolism. The purpose of this review is to describe the effects of these drugs on bone metabolism and fracture risk. Osteoporosis is a progressive skeletal disorder that is characterized by compromised bone strength and increased risk of fracture. This condition has become an important global health problem, affecting approximately 200 million people worldwide. Another chronic and highly prevalent condition is diabetes mellitus, which affects more than 380 million people; both type 1 and type 2 diabetes are risk factors for fracture. Type 2 diabetes, in particular, is associated with impaired bone strength, although it is characterized by normal or elevated bone mineral density. Several therapeutic strategies are available to achieve the best outcomes in the management of diabetes mellitus but these have different effects on bone metabolism. The purpose of this narrative review is to describe the effects of oral hypoglycemic agents (metformin, sulfonylureas, thiazolidinediones, meglitinides, dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists and sodium-dependent glucose transporter 2 inhibitors) on bone metabolism and on the risk of developing fragility fractures in patients with type 2 diabetes. Both diabetes and osteoporosis represent a significant burden in terms of healthcare costs and quality of life. It is very important to choose therapies for diabetes that ensure good metabolic control whilst preserving skeletal health.
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Affiliation(s)
- A Palermo
- Department of Endocrinology and Diabetes, University Campus Bio-Medico of Rome, Via Alvaro del Portillo, 21-00128, Rome, Italy
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28
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Styner M, Pagnotti GM, Galior K, Wu X, Thompson WR, Uzer G, Sen B, Xie Z, Horowitz MC, Styner MA, Rubin C, Rubin J. Exercise Regulation of Marrow Fat in the Setting of PPARγ Agonist Treatment in Female C57BL/6 Mice. Endocrinology 2015; 156:2753-61. [PMID: 26052898 PMCID: PMC4511140 DOI: 10.1210/en.2015-1213] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The contribution of marrow adipose tissue (MAT) to skeletal fragility is poorly understood. Peroxisome proliferator-activated receptor (PPAR)γ agonists, associated with increased fractures in diabetic patients, increase MAT. Here, we asked whether exercise could limit the MAT accrual and increase bone formation in the setting of PPARγ agonist treatment. Eight-week-old female C57BL/6 mice were treated with 20-mg/kg · d rosiglitazone (Rosi) and compared with control (CTL) animals. Exercise groups ran 12 km/d when provided access to running wheels (CTL exercise [CTL-E], Rosi-E). After 6 weeks, femoral MAT (volume of lipid binder osmium) and tibial bone morphology were assessed by microcomputer tomography. Rosi was associated with 40% higher femur MAT volume compared with CTL (P < .0001). Exercise suppressed MAT volume by half in CTL-E mice compared with CTL (P < .01) and 19% in Rosi-E compared with Rosi (P < .0001). Rosi treatment increased fat markers perilipin and fatty acid synthase mRNA by 4-fold (P < .01). Exercise was associated with increased uncoupling protein 1 mRNA expression in both CTL-E and Rosi-E groups (P < .05), suggestive of increased brown fat. Rosi increased cortical porosity (P < .0001) but did not significantly impact trabecular or cortical bone quantity. Importantly, exercise induction of trabecular bone volume was not prevented by Rosi (CTL-E 21% > CTL, P < .05; Rosi-E 26% > Rosi, P < .01). In summary, despite the Rosi induction of MAT extending well into the femoral diaphysis, exercise was able to significantly suppress MAT volume and induce bone formation. Our results suggest that the impact of PPARγ agonists on bone and marrow health can be partially mitigated by exercise.
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Affiliation(s)
- Maya Styner
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Gabriel M Pagnotti
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Kornelia Galior
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Xin Wu
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - William R Thompson
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Gunes Uzer
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Buer Sen
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Zhihui Xie
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Mark C Horowitz
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Martin A Styner
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Clinton Rubin
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
| | - Janet Rubin
- Department of Medicine (M.S., K.G., X.W., G.U., B.S., Z.X., J.R.), University of North Carolina, Chapel Hill, North Carolina; Department of Physical Therapy (W.R.T.), Indiana University, Indianapolis, Indiana; Department of Computer Science (M.A.S.), University of North Carolina, Chapel Hill, North Carolina; Department of Psychiatry (M.A.S.), Image Analysis, University of North Carolina, Chapel Hill, North Carolina; Department of Biomedical Engineering (G.M.P., C.R.), Stony Brook University, Stony Brook, New York; and Department of Orthopedics and Rehabilitation (M.C.H.), Yale University, New Haven, Connecticut
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29
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Abstract
Obesity and osteoporosis are two of the most common chronic disorders of the 21st century. Both are accompanied by significant morbidity. The only place in the mammalian organism where bone and fat lie adjacent to each other is in the bone marrow. Marrow adipose tissue is a dynamic depot that probably exists as both constitutive and regulated compartments. Adipocytes secrete cytokines and adipokines that either stimulate or inhibit adjacent osteoblasts. The relationship of marrow adipose tissue to other fat depots is complex and might play very distinct parts in modulation of metabolic homoeostasis, haemopoiesis, and osteogenesis. Understanding of the relationship between bone and fat cells that arise from the same progenitor within the bone marrow niche provides insight into the pathophysiology of age-related osteoporosis, diabetes, and obesity.
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Affiliation(s)
| | - Clifford J Rosen
- Maine Medical Center Research Institute, Scarborough, ME 04074, USA
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30
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Mosti MP, Stunes AK, Ericsson M, Pullisaar H, Reseland JE, Shabestari M, Eriksen EF, Syversen U. Effects of the peroxisome proliferator-activated receptor (PPAR)-δ agonist GW501516 on bone and muscle in ovariectomized rats. Endocrinology 2014; 155:2178-89. [PMID: 24708238 DOI: 10.1210/en.2013-1166] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Estrogen deficiency promotes bone loss and skeletal muscle dysfunction. Peroxisome proliferator-activated receptors (PPARs) have 3 subtypes (α, δ, and γ). PPARγ agonists induce bone loss, whereas PPARα agonists increase bone mass. Although PPARδ agonists are known to influence skeletal muscle metabolism, the skeletal effects are unsettled. This study investigated the musculoskeletal effects of the PPARδ agonist GW501516 in ovariectomized (OVX) rats. Female Sprague Dawley rats, 12 weeks of age, were allocated to a sham-operated group and 3 OVX groups; high-dose GW501516 (OVX-GW5), low-dose GW501516 (OVX-GW1), and a control group (OVX-CTR), respectively (n = 12 per group). Animals received GW501516 or vehicle (methylcellulose) daily for 4 months by gavage. Bone mineral density (BMD) was assessed by dual x-ray absorptiometry at the femur, spine, and whole body. Bone microarchitecture at the proximal tibia was assessed by microcomputed tomography, and dynamic histomorphometry was performed. Quadriceps muscle morphology and the relative expression of mitochondrial proteins were analyzed. Bone metabolism markers and metabolic markers were measured in plasma. After 4 months, the OVX-GW5 group displayed lower femoral BMD than OVX-CTR. Trabecular separation was higher in the GW-treated groups, compared with OVX-CTR. The OVX-GW5 group also exhibited lower cortical area fraction and a higher structure model index than OVX-CTR. These effects coincided with impaired bone formation in both GW groups. The OVX-GW5 group displayed elevated triglyceride levels and reduced adiponectin levels, whereas no effects on muscle morphology or mitochondrial gene expression appeared. In summary, the PPARδ agonist GW501516 negatively affected bone properties in OVX rats, whereas no effects were detected in skeletal muscle.
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Affiliation(s)
- M P Mosti
- Department of Cancer Research and Molecular Medicine (M.P.M., A.K.S., U.S.), Norwegian University of Science and Technology, N-7491 Trondheim, Norway; Department of Medical Biosciences, Physiological Chemistry (M.E.), Umeå University, SE-901 85 Umeå, Sweden; Department of Biomaterials (H.P., J.E.R., M.S.), Institute for Clinical Dentistry, University of Oslo, 0317 Oslo, Norway; Department of Endocrinology (E.F.E.), Oslo University Hospital, 0424 Oslo, Norway; and Department of Endocrinology (U.S.), St Olav's University Hospital HF, 7030 Trondheim, Norway
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31
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Peroxisome proliferator-activated receptor γ ligands retard cultured vascular smooth muscle cells calcification induced by high glucose. Cell Biochem Biophys 2014; 66:421-9. [PMID: 23274912 DOI: 10.1007/s12013-012-9490-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) and its ligands have profound effects on glucose homeostasis, cardiovascular diseases, and bone metabolism. To explore the pathophysiological roles of PPARγ in diabetes with concomitant vascular calcification, we investigated changes in PPARγ expression and the effect of the PPARγ ligands troglitazone and rosiglitazone on vascular smooth muscle cell (VSMC) calcification induced by high glucose (HG, 25 mmol/L). Compared with low glucose, HG-induced VSMC calcification, and PPARγ mRNA, protein level was decreased. Troglitazone and rosiglitazone treatment markedly attenuated the VSMC calcification, whereas PPARγ antagonist GW9662 abolished the effect of rosiglitazone on calcification. Pretreatment of VSMCs with rosiglitazone, but not troglitazone, restored the loss of lineage marker expression: the protein levels of α-actin and SM-22α were increased 52 % (P < 0.05) and 53.1% (P < 0.01), respectively, as compared with HG alone. Troglitazone and rosiglitazone reversed the change in bone-related protein expression induced by HG: decreased the mRNA levels of osteocalcin, bone morphogenetic protein 2 (BMP2), and core binding factor α 1 (Cbfα-1) by 26.9% (P > 0.05), 50.0 % (P < 0.01), and 24.4% (P < 0.05), and 48.4% (P < 0.05), 41.4% (P < 0.01) and 56.2% (P < 0.05), respectively, and increased that of matrix Gla protein (MGP) 84.2% (P < 0.01) and 70.0%, respectively (P < 0.05), as compared with HG alone. GW9662 abolished the effect of rosiglitazone on Cbfα-1 and MGP expression. PPARγ ligands can inhibit VSMCs calcification induced by high glucose.
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32
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Gallagher EJ, Sun H, Kornhauser C, Tobin-Hess A, Epstein S, Yakar S, LeRoith D. The effect of dipeptidyl peptidase-IV inhibition on bone in a mouse model of type 2 diabetes. Diabetes Metab Res Rev 2014; 30:191-200. [PMID: 24023014 PMCID: PMC5496098 DOI: 10.1002/dmrr.2466] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 09/05/2013] [Indexed: 02/05/2023]
Abstract
BACKGROUND Individuals with type 2 diabetes (T2D) are at greater risk of bone fractures than those without diabetes. Certain oral diabetic medications may further increase the risk of fracture. Dipeptidyl peptidase-IV (DPP-IV) inhibitors are incretin-based therapies that are being increasingly used for the management of T2D. It has been hypothesized that these agents may reduce fracture risk in those with T2D. In this study, we used a mouse model of T2D to examine the effects of the DPP-IV inhibitor, MK-0626, on bone. METHODS Male wild type (WT) and diabetic muscle-lysine-arginine (MKR) mice were treated with MK-0626, pioglitazone, alendronate or vehicle. The effects of treatment with MK-0626 on bone microarchitecture and turnover were compared with treatment with pioglitazone, alendronate and vehicle. Osteoblast differentiation was determined by alkaline phosphatase staining of bone marrow cells from WT and MKR mice after treatment with pioglitazone, MK-0626 or phosphate buffered saline. RESULTS We found that MK-0626 had neutral effects on cortical and trabecular bone in diabetic mice. Pioglitazone had detrimental effects on the trabecular bone of WT but not of diabetic mice. Alendronate caused improvements in cortical and trabecular bone architecture in diabetic and WT mice. MK-0626 did not alter osteoblast differentiation, but pioglitazone impaired osteoblast differentiation in vitro. CONCLUSIONS Overall, the DPP-IV inhibitor, MK-0626, had no adverse effects on bone in an animal model of T2D or directly on osteoblasts in culture. These findings are reassuring as DPP-IV inhibitors are being widely used to treat patients with T2D who are already at an increased risk of fractures.
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Affiliation(s)
- Emily Jane Gallagher
- Division of Endocrinology, Diabetes and Bone Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
| | - Hui Sun
- David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, USA
| | - Caroline Kornhauser
- Division of Endocrinology, Diabetes and Bone Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
| | - Aviva Tobin-Hess
- Division of Endocrinology, Diabetes and Bone Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
| | - Sol Epstein
- Department of Medicine and Geriatrics, Mount Sinai School of Medicine, New York, NY, USA
| | - Shoshana Yakar
- David B. Kriser Dental Center, Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, USA
| | - Derek LeRoith
- Division of Endocrinology, Diabetes and Bone Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
- Correspondence to: Derek LeRoith, Division of Endocrinology, Metabolism, and Bone Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA.
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Patel JJ, Butters OR, Arnett TR. PPAR agonists stimulate adipogenesis at the expense of osteoblast differentiation while inhibiting osteoclast formation and activity. Cell Biochem Funct 2014; 32:368-77. [PMID: 24615887 DOI: 10.1002/cbf.3025] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/08/2013] [Accepted: 12/22/2013] [Indexed: 12/13/2022]
Abstract
Drugs used in the treatment of type 2 diabetes and cardiovascular disease, specifically peroxisome proliferator-activated receptor (PPAR) agonists, have been reported to affect bone cell function and fracture risk. In this study, we assessed the direct effects of PPAR-γ agonists (rosiglitazone and troglitazone), used in the treatment of diabetes, and a PPAR-α agonist (fenofibrate), used to treat hyperlipidaemia, on the function of primary osteoblasts and osteoclasts. Formation of 'trabecular' bone structures by rat calvarial osteoblasts was reduced by up to 85% in cultures treated with rosiglitazone and by 45% in troglitazone-treated or fenofibrate-treated cultures; at the same time, lipid droplet formation was increased by 40-70%. The expression of key osteogenic markers was similarly downregulated in cultures treated with PPAR agonists, whereas adipogenesis markers were upregulated. Formation of osteoclasts in cultures derived from mouse marrow diminished with fenofibrate treatment, whereas both glitazones reduced resorptive activity without affecting osteoclast number. Metformin, although not a PPAR agonist, is also commonly used in the treatment of type 2 diabetes. Here, metformin was found to have no effect on bone cell function. Taken together, these data suggest that PPAR-γ agonists may enhance bone loss via increased adipogenesis at the expense of osteoblast formation. In contrast, PPAR-α agonists may prevent bone loss. Given that the prevalence of diabetes and cardiovascular disease is expected to rise significantly, greater attention may need to be paid to the effects of PPAR agonists on bone homeostasis.
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Affiliation(s)
- Jessal J Patel
- Department of Cell and Developmental Biology, University College London, London, UK
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34
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Hah YS, Joo HH, Kang YH, Park BW, Hwang SC, Kim JW, Sung IY, Rho GJ, Woo DK, Byun JH. Cultured human periosteal-derived cells have inducible adipogenic activity and can also differentiate into osteoblasts in a perioxisome proliferator-activated receptor-mediated fashion. Int J Med Sci 2014; 11:1116-28. [PMID: 25170294 PMCID: PMC4147637 DOI: 10.7150/ijms.9611] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 08/06/2014] [Indexed: 01/09/2023] Open
Abstract
We investigated the adipogenic activity of cultured human periosteal-derived cells and studied perioxisome proliferator-activated receptor (PPAR) ligand-mediated differentiation of cultured human periosteal-derived cells into osteoblasts. Periosteal-derived cells expressed adipogenic markers, including CCAAT/enhancer binding protein α (C/EBP- α), C/EBP-δ, aP2, leptin, LPL, and PPARγ. Lipid vesicles were formed in the cytoplasm of periosteal-derived cells. Thus, periosteal-derived cells have potential adipogenic activity. The PPARα and PPARγ agonists, WY14643 and pioglitazone, respectively, did not modulate alkaline phosphatase (ALP) activity in periosteal-derived cells during induced osteoblastic differentiation, however, the PPARα and PPARγ antagonists, GW6471 and T0070907, respectively, both decreased ALP activity in these cells. WY14643 did not affect, whereas pioglitazone enhanced, alizarin red-positive mineralization and calcium content in the periosteal-derived cells. GW6471 and T0070907 both decreased mineralization and calcium content. By RT-PCR, pioglitazone significantly increased ALP expression in periosteal-derived cells between culture day 3 and 2 weeks. Pioglitazone increased Runx2 expression after 3 days, which declined thereafter, but did not alter osteocalcin expression. Both of GW6471 and T0070907 decreased ALP mRNA expression. These results suggest that pioglitazone enhances osteoblastic differentiation of periosteal-derived cells by increasing Runx2 and ALP mRNA expression, and increasing mineralization. GW6471 and T0070907 inhibit osteoblastic differentiation of the periosteal-derived cells by decreasing ALP expression and mineralization in the periosteal-derived cells. In conclusion, although further study will be needed to clarify the mechanisms of PPAR-regulated osteogenesis, our results suggest that PPARγ agonist stimulates osteoblastic differentiation of cultured human periosteal-derived cells and PPARα and PPARγ antagonists inhibit osteoblastic differentiation in these cells.
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Affiliation(s)
- Young-Sool Hah
- 1. Clinical Research Institute of Gyeongsang National University Hospital, Jinju, Republic of Korea
| | - Hyun-Ho Joo
- 2. Department of Oral and Maxillofacial Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Young-Hoon Kang
- 2. Department of Oral and Maxillofacial Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Bong-Wook Park
- 2. Department of Oral and Maxillofacial Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Sun-Chul Hwang
- 3. Department of Orthopaedic Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Jong-Woo Kim
- 4. Department of Thoracic and Cardiovascular Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Iel-Yong Sung
- 5. Department of Oral and Maxillofacial Surgery, College of Medicine, Ulsan University, Ulsan, Republic of Korea
| | - Gyu-Jin Rho
- 6. OBS/Theriogenology and Biotechnology, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Dong Kyun Woo
- 7. College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - June-Ho Byun
- 2. Department of Oral and Maxillofacial Surgery, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
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35
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Koufany M, Chappard D, Netter P, Bastien C, Weryha G, Jouzeau JY, Moulin D. The Peroxisome Proliferator-Activated Receptor γ Agonist Pioglitazone Preserves Bone Microarchitecture in Experimental Arthritis by Reducing the Interleukin-17-Dependent Osteoclastogenic Pathway. ACTA ACUST UNITED AC 2013; 65:3084-95. [DOI: 10.1002/art.38130] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 08/08/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Meriem Koufany
- UMR-7365, CNRS, Université de Lorraine; Vandoeuvre-lès-Nancy France
| | - Daniel Chappard
- IRIS-IBS Institut de Biologie en Santé and Centre Hospitalier Universitaire d'Angers; Angers France
| | - Patrick Netter
- UMR-7365, CNRS, Université de Lorraine; Vandoeuvre-lès-Nancy France
- Centre Hospitalier Régional et Universitaire; Nancy France
| | - Claire Bastien
- Centre Hospitalier Régional et Universitaire; Vandoeuvre-lès-Nancy France
| | - Georges Weryha
- Centre Hospitalier Régional et Universitaire; Vandoeuvre-lès-Nancy France
| | - Jean-Yves Jouzeau
- UMR-7365, CNRS, Université de Lorraine; Vandoeuvre-lès-Nancy France
- Centre Hospitalier Régional et Universitaire; Nancy France
| | - David Moulin
- UMR-7365, CNRS, Université de Lorraine; Vandoeuvre-lès-Nancy France
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36
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Marder W, Khalatbari S, Myles JD, Hench R, Lustig S, Yalavarthi S, Parameswaran A, Brook RD, Kaplan MJ. The peroxisome proliferator activated receptor-γ pioglitazone improves vascular function and decreases disease activity in patients with rheumatoid arthritis. J Am Heart Assoc 2013; 2:e000441. [PMID: 24252844 PMCID: PMC3886758 DOI: 10.1161/jaha.113.000441] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Background Rheumatoid arthritis (RA) is associated with heightened mortality due to atherosclerotic cardiovascular disease (CVD). Inflammatory pathways in RA negatively affect vascular physiology and promote metabolic disturbances that contribute to CVD. We hypothesized that the peroxisome proliferator activated receptor‐γ (PPAR‐γ) pioglitazone could promote potent vasculoprotective and anti‐inflammatory effects in RA. Methods and Results One hundred forty‐three non‐diabetic adult RA patients (76.2% female, age 55.2±12.1 [mean±SD]) on stable RA standard of care treatment were enrolled in a randomized, double‐blind placebo controlled crossover trial of 45 mg daily pioglitazone versus placebo, with a 3‐month duration/arm and a 2‐month washout period. Pulse wave velocity of the aorta (PWV), brachial artery flow mediated dilatation (FMD), nitroglycerin mediated dilatation (NMD), microvascular endothelial function (reactive hyperemia index [RHI]), and circulating biomarkers of inflammation, insulin resistance, and atherosclerosis risk all were quantified. RA disease activity was assessed with the 28‐Joint Count Disease Activity Score (DAS‐28) C‐reactive protein (CRP) and the Short Form (36) Health Survey quality of life questionnaire. When added to standard of care RA treatment, pioglitazone significantly decreased pulse wave velocity (ie, aortic stiffness) (P=0.01), while FMD and RHI remained unchanged when compared to treatment with placebo. Further, pioglitazone significantly reduced RA disease activity (P=0.02) and CRP levels (P=0.001), while improving lipid profiles. The drug was well tolerated. Conclusions Addition of pioglitazone to RA standard of care significantly improves aortic elasticity and decreases inflammation and disease activity with minimal safety issues. The clinical implications of these findings remain to be established. Clinical Trial Registration URL: ClinicalTrials.gov Unique Identifier: NCT00554853.
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Affiliation(s)
- Wendy Marder
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI
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37
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Lamontagne J, Jalbert-Arsenault É, Pepin É, Peyot ML, Ruderman NB, Nolan CJ, Joly E, Madiraju SM, Poitout V, Prentki M. Pioglitazone acutely reduces energy metabolism and insulin secretion in rats. Diabetes 2013; 62:2122-9. [PMID: 23378607 PMCID: PMC3661607 DOI: 10.2337/db12-0428] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Our objective was to determine if the insulin-sensitizing drug pioglitazone acutely reduces insulin secretion and causes metabolic deceleration in vivo independently of change in insulin sensitivity. We assessed glucose homeostasis by hyperinsulinemic-euglycemic and hyperglycemic clamp studies and energy expenditure by indirect calorimetry and biotelemetry in male Wistar and obese hyperinsulinemic Zucker diabetic fatty (ZDF) rats 45 min after a single oral dose of pioglitazone (30 mg/kg). In vivo insulin secretion during clamped hyperglycemia was reduced in both Wistar and ZDF rats after pioglitazone administration. Insulin clearance was slightly increased in Wistar but not in ZDF rats. Insulin sensitivity in Wistar rats assessed by the hyperinsulinemic-euglycemic clamp was minimally affected by pioglitazone at this early time point. Pioglitazone also reduced energy expenditure in Wistar rats without altering respiratory exchange ratio or core body temperature. Glucose-induced insulin secretion (GIIS) and oxygen consumption were reduced by pioglitazone in isolated islets and INS832/13 cells. In conclusion, pioglitazone acutely induces whole-body metabolic slowing down and reduces GIIS, the latter being largely independent of the insulin-sensitizing action of the drug. The results suggest that pioglitazone has direct metabolic deceleration effects on the β-cell that may contribute to its capacity to lower insulinemia and antidiabetic action.
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Affiliation(s)
- Julien Lamontagne
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
- Department of Biochemistry, Université de Montréal, Montreal, Quebec, Canada
| | - Élise Jalbert-Arsenault
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Émilie Pepin
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
- Program of Molecular Biology, Université de Montréal, Montreal, Quebec, Canada
| | - Marie-Line Peyot
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
| | - Neil B. Ruderman
- Departments of Medicine and Physiology and Biophysics, Boston University School of Medicine and Diabetes Unit, Section of Endocrinology, Boston University School of Medicine and Boston Medical Center, Boston, Massachusetts
| | | | - Erik Joly
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
| | - S.R. Murthy Madiraju
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
| | - Vincent Poitout
- Montreal Diabetes Research Center at the CRCHUM and Departments of Medicine, Biochemistry and Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Marc Prentki
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Université de Montréal, Montreal, Quebec, Canada
- Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
- Department of Biochemistry, Université de Montréal, Montreal, Quebec, Canada
- Corresponding author: Marc Prentki,
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38
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Schwartz AV, Vittinghoff E, Margolis KL, Scibora LM, Palermo L, Ambrosius WT, Hue TF, Ensrud KE. Intensive glycemic control and thiazolidinedione use: effects on cortical and trabecular bone at the radius and tibia. Calcif Tissue Int 2013; 92:477-86. [PMID: 23377193 PMCID: PMC3640571 DOI: 10.1007/s00223-013-9703-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 01/13/2013] [Indexed: 01/17/2023]
Abstract
Factors that contribute to bone fragility in type 2 diabetes are not well understood. We assessed the effects of intensive glycemic control, thiazolidinediones (TZDs), and A1C levels on bone geometry and strength at the radius and tibia. In a substudy of the Action to Control Cardiovascular Risk in Diabetes trial, peripheral quantitative computed tomographic (pQCT) scans of the radius and tibia were obtained 2 years after randomization on 73 participants (intensive n = 35, standard n = 38). TZD use and A1C levels were measured every 4 months during the trial. Effects of intervention assignment, TZD use, and A1C on pQCT parameters were assessed in linear regression models. Intensive, compared with standard, glycemic control was associated with 1.3 % lower cortical volumetric BMD at the tibia in men (p = 0.02) but not with other pQCT parameters. In women, but not men, each additional year of TZD use was associated with an 11 % lower polar strength strain index (SSIp) at the radius (p = 0.04) and tibia (p = 0.002) in models adjusted for A1C levels. In women, each additional 1 % increase in A1C was associated with an 18 % lower SSIp at the ultradistal radius (p = 0.04) in models adjusted for TZD use. There was no consistent evidence of an effect of intensive, compared with standard, glycemic control on bone strength at the radius or tibia. In women, TZD use may reduce bone strength at these sites. Higher A1C may also be associated with lower bone strength at the radius, but not tibia, in women.
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Affiliation(s)
- Ann V Schwartz
- University of California, 185 Berry St., Suite 5700, San Francisco, CA 94107, USA.
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Imai Y, Youn MY, Inoue K, Takada I, Kouzmenko A, Kato S. Nuclear receptors in bone physiology and diseases. Physiol Rev 2013; 93:481-523. [PMID: 23589826 PMCID: PMC3768103 DOI: 10.1152/physrev.00008.2012] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
During the last decade, our view on the skeleton as a mere solid physical support structure has been transformed, as bone emerged as a dynamic, constantly remodeling tissue with systemic regulatory functions including those of an endocrine organ. Reflecting this remarkable functional complexity, distinct classes of humoral and intracellular regulatory factors have been shown to control vital processes in the bone. Among these regulators, nuclear receptors (NRs) play fundamental roles in bone development, growth, and maintenance. NRs are DNA-binding transcription factors that act as intracellular transducers of the respective ligand signaling pathways through modulation of expression of specific sets of cognate target genes. Aberrant NR signaling caused by receptor or ligand deficiency may profoundly affect bone health and compromise skeletal functions. Ligand dependency of NR action underlies a major strategy of therapeutic intervention to correct aberrant NR signaling, and significant efforts have been made to design novel synthetic NR ligands with enhanced beneficial properties and reduced potential negative side effects. As an example, estrogen deficiency causes bone loss and leads to development of osteoporosis, the most prevalent skeletal disorder in postmenopausal women. Since administration of natural estrogens for the treatment of osteoporosis often associates with undesirable side effects, several synthetic estrogen receptor ligands have been developed with higher therapeutic efficacy and specificity. This review presents current progress in our understanding of the roles of various nuclear receptor-mediated signaling pathways in bone physiology and disease, and in development of advanced NR ligands for treatment of common skeletal disorders.
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Affiliation(s)
- Yuuki Imai
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan.
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Bonnelye E, Aubin JE. An energetic orphan in an endocrine tissue: a revised perspective of the function of estrogen receptor-related receptor alpha in bone and cartilage. J Bone Miner Res 2013; 28:225-33. [PMID: 23212690 DOI: 10.1002/jbmr.1836] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 11/09/2012] [Accepted: 11/14/2012] [Indexed: 01/07/2023]
Abstract
Estrogen receptor-related receptor alpha (ERRα) is an orphan nuclear receptor with sequence homology to the estrogen receptors, ERα/β, but it does not bind estrogen. ERRα not only plays a functional role in osteoblasts but also in osteoclasts and chondrocytes. In addition, the ERRs, including ERRα, can be activated by coactivators such as peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC1α and β) and are implicated in adipogenesis, fatty acid oxidation, and oxidative stress defense, suggesting that ERRα-through its activity in bone resorption and adipogenesis--may regulate the insulin and leptin pathways and contribute to aging-related changes in bone and cartilage. In this review, we discuss data on ERRα and its cellular and molecular modes of action, which have broad implications for considering the potential role of this orphan receptor in cartilage and bone endocrine function, on whole-organism physiology, and in the bone aging process.
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Abstract
Peroxisome proliferator-activated receptors (PPARs) are members of the steroid hormone receptor superfamily, discovered in 1990. To date, three PPAR subtypes have been identified; PPARα, PPAR β/δ, and PPARγ. These receptors share a high degree of homology but differ in tissue distribution and ligand specificity. PPARs have been implicated in the etiology as well as treatment of several important diseases and pathological conditions such as diabetes, inflammation, senescence-related diseases, regulation of fertility, and various types of cancer. Consequently, significant efforts to discover novel PPAR roles and delineate molecular mechanisms involved in their activation and repression as well as develop safer and more effective PPAR modulators, as therapeutic agents to treat a myriad of diseases and conditions, are underway. This volume of Methods in Molecular Biology contains details of experimental protocols used in researching these receptors.
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Affiliation(s)
- Jihan Youssef
- University of Missouri-Kansas City, Kansas City, MO, USA
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Bortolini M, Wright MB, Bopst M, Balas B. Examining the safety of PPAR agonists - current trends and future prospects. Expert Opin Drug Saf 2012; 12:65-79. [PMID: 23134541 DOI: 10.1517/14740338.2013.741585] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION The peroxisome proliferator-activated receptor (PPAR)-α and -γ agonists, fibrates and glitazones, are effective treatments for dyslipidemia and type 2 diabetes mellitus, respectively, but exhibit class-related, as well as compound-specific safety characteristics. AREAS COVERED This article reviews the profiles of PPAR-α, PPAR-γ, and dual PPAR-α/γ agonists with regard to class-related and compound-specific efficacy and adverse effects. We explore how learnings from first-generation drugs are being applied to develop safer PPAR-targeted therapies. EXPERT OPINION The finding that rosiglitazone may increase risk for cardiovascular events has led to regulatory guidelines requiring demonstration of cardiovascular safety in appropriate outcome trials for new type 2 diabetes mellitus drugs. The emerging data on the possibly increased risk of bladder cancer with pioglitazone may prompt the need for post-approval safety studies for new drugs. Since PPAR-α and -γ affect key cardiometabolic risk factors (diabetic dyslipidemia, insulin resistance, hyperglycemia, and inflammation) in a complementary fashion, combining their benefits has emerged as a particularly attractive option. New PPAR-targeted therapies that balance the relative potency and/or activity toward PPAR-α and -γ have shown promise in retaining efficacy while reducing potential side effects.
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Affiliation(s)
- Michele Bortolini
- Cardiometabolic Franchise Safety Science Leader, F. Hoffmann-La Roche, Ltd, PDS-Safety Risk Management, 663/2028, CH4070 Basel, Switzerland.
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Treatment with pharmacological PPARα agonists stimulates the ubiquitin proteasome pathway and myofibrillar protein breakdown in skeletal muscle of rodents. Biochim Biophys Acta Gen Subj 2012; 1830:2105-17. [PMID: 23041501 DOI: 10.1016/j.bbagen.2012.09.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 09/28/2012] [Accepted: 09/28/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND Treatment of hyperlipidemic patients with fibrates, agonists of peroxisome proliferator-activated receptor α (PPARα), provokes muscle atrophy as a side effect. The molecular mechanism underlying this phenomenon is still unknown. We tested the hypothesis that activation of PPARα leads to an up-regulation of the ubiquitin proteasome system (UPS) which plays a major role in protein degradation in muscle. METHODS Rats, wild-type and PPARα-deficient mice (PPARα(-/-)) were treated with synthetic PPARα agonists (clofibrate, WY-14,643) to study their effect on the UPS and myofibrillar protein breakdown in muscle. RESULTS In rats and wild-type mice but not PPARα(-/-) mice, clofibrate or WY-14,643 caused increases in mRNA and protein levels of the ubiquitin ligases atrogin-1 and MuRF1 in muscle. Wild-type mice treated with WY-14,643 had a greater 3-methylhistidine release from incubated muscle and lesser muscle weights. In addition, wild-type mice but not PPARα(-/-) mice treated with WY-14,643 had higher amounts of ubiquitin-protein conjugates, a decreased activity of PI3K/Akt1 signalling, and an increased activity of FoxO1 transcription factor in muscle. Reporter gene and gel shift experiments revealed that the atrogin-1 and MuRF1 promoter do not contain functional PPARα DNA-binding sites. CONCLUSIONS These findings indicate that fibrates stimulate ubiquitination of proteins in skeletal muscle which in turn stimulates protein degradation. Up-regulation of ubiquitin ligases is probably not mediated by PPARα-dependent gene transcription but by PPARα-dependent inhibition of the PI3K/Akt1 signalling pathway leading to activation of FoxO1. GENERAL SIGNIFICANCE PPARα plays a role in the regulation of the ubiquitin proteasome system.
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Samadfam R, Awori M, Bénardeau A, Bauss F, Sebokova E, Wright M, Smith SY. Combination treatment with pioglitazone and fenofibrate attenuates pioglitazone-mediated acceleration of bone loss in ovariectomized rats. J Endocrinol 2012; 212:179-86. [PMID: 22062085 DOI: 10.1530/joe-11-0356] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peroxisome proliferator-activated receptor (PPAR) γ agonists, such as pioglitazone (Pio), improve glycemia and lipid profile but are associated with bone loss and fracture risk. Data regarding bone effects of PPARα agonists (including fenofibrate (Feno)) are limited, although animal studies suggest that Feno may increase bone mass. This study investigated the effects of a 13-week oral combination treatment with Pio (10 mg/kg per day)+Feno (25 mg/kg per day) on body composition and bone mass parameters compared with Pio or Feno alone in adult ovariectomized (OVX) rats, with a 4-week bone depletion period, followed by a 6-week treatment-free period. Treatment of OVX rats with Pio+Feno resulted in ∼50% lower fat mass gain compared with Pio treatment alone. Combination treatment with Pio+Feno partially prevented Pio-induced loss of bone mineral content (∼45%) and bone mineral density (BMD; ∼60%) at the lumbar spine. Similar effects of treatments were observed at the femur, most notably at sites rich in trabecular bone. At the proximal tibial metaphysis, concomitant treatment with Pio+Feno prevented Pio exacerbation of ovariectomy-induced loss of trabecular bone, resulting in BMD values in the Pio+Feno group comparable to OVX controls. Discontinuation of Pio or Feno treatment of OVX rats was associated with partial reversal of effects on bone loss or bone mass gain, respectively, while values in the Pio+Feno group remained comparable to OVX controls. These data suggest that concurrent/dual agonism of PPARγ and PPARα may reduce the negative effects of PPARγ agonism on bone mass.
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Affiliation(s)
- Rana Samadfam
- Charles River Laboratories, 22022 Transcanadienne, Senneville, Montréal, Québec, Canada H9X 3R3
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Skeletal effects of the saturated 3-thia Fatty Acid tetradecylthioacetic Acid in rats. PPAR Res 2011; 2011:436358. [PMID: 22190907 PMCID: PMC3236357 DOI: 10.1155/2011/436358] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 09/06/2011] [Indexed: 01/23/2023] Open
Abstract
This study explores the skeletal effects of the peroxisome proliferator activated receptor (PPAR)pan agonist tetradecylthioacetic acid (TTA). Rats, without (Study I) and with ovariectomy (OVX) or sham operation (Study II), were given TTA or vehicle daily for 4 months. Bone markers in plasma, whole body and femoral bone mineral density and content (BMD and BMC), and body composition were examined. Histomorphometric and biomechanical analyses (Study I) and biomechanical and μCT analyses (Study II) of the femur were performed. Normal rats fed TTA had higher femoral BMD and increased total and cortical area in femur compared to controls. The ovariectomized groups had decreased BMD and impaired microarchitecture parameters compared to SHAM. However, the TTA OVX group maintained femoral BMC, trabecular thickness in the femoral head, and cortical volume in the femoral metaphysis as SHAM. TTA might increase BMD and exert a light preventive effect on estrogen-related bone loss in rats.
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Abstract
Thiazolidinediones are widely used effective drugs for the management of hyperglycaemia in Type 2 diabetes and may provide additional metabolic benefits. Any advantages of these agents need to be considered in the context of any potential risk from adverse events. Recent evidence from several sources, including large-scale randomized controlled trials and observational studies, suggests that long-term use of thiazolidinediones is associated with bone loss and an increased risk of fractures in women with Type 2 diabetes. As patients with Type 2 diabetes are already at high risk for fractures, the clinical relevance of this reported association with thiazolidinedione therapy deserves careful consideration. Generally, the fracture risk with thiazolidinediones appears similar in magnitude to that associated with several other widely used drug classes, although there are unanswered questions regarding susceptibility factors, differential effects on bone sites and potential management approaches. This article provides a comprehensive overview of the evidence for an increase in fracture risk with thiazolidinediones and places it in the context of recent analyses of fracture risk with other commonly used drug classes. The potential clinical implications of any association are also discussed.
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Affiliation(s)
- D J Betteridge
- Department of Medicine, Royal Free and University College Medical School, London, UK.
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Yanik SC, Baker AH, Mann KK, Schlezinger JJ. Organotins are potent activators of PPARγ and adipocyte differentiation in bone marrow multipotent mesenchymal stromal cells. Toxicol Sci 2011; 122:476-88. [PMID: 21622945 DOI: 10.1093/toxsci/kfr140] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Adipocyte differentiation in bone marrow is potentially deleterious to both bone integrity and lymphopoiesis. Here, we examine the hypothesis that organotins, common environmental contaminants that are dual ligands for peroxisome proliferator-activated receptor (PPAR) γ and its heterodimerization partner retinoid X receptor (RXR), are potent activators of bone marrow adipogenesis. A C57Bl/6-derived bone marrow multipotent mesenchymal stromal cell (MSC) line, BMS2, was treated with rosiglitazone, a PPARγ agonist, bexarotene, an RXR agonist, or a series of organotins. Rosiglitazone and bexarotene potently activated adipocyte differentiation; however, bexarotene had a maximal efficacy of only 20% of that induced by rosiglitazone. Organotins (tributyltin [TBT], triphenyltin, and dibutyltin) also stimulated adipocyte differentiation (EC₅₀ of 10-20 nM) but with submaximal, structure-dependent efficacy. In coexposures, both bexarotene and TBT enhanced rosiglitazone-induced adipogenesis. To investigate the contribution of PPARγ to TBT-induced adipogenesis, we examined expression of PPARγ2, as well as its transcriptional target FABP4. TBT-induced PPARγ2 and FABP4 protein expression with an efficacy intermediate between rosiglitazone and bexarotene, similar to lipid accumulation. A PPARγ antagonist and PPARγ-specific small hairpin RNA suppressed TBT-induced differentiation, although to a lesser extent than rosiglitazone-induced differentiation, suggesting that TBT may engage alternate pathways. TBT and bexarotene, but not rosiglitazone, also induced the expression of TGM2 (an RXR target) and ABCA1 (a liver X receptor target). The results show that an environmental contaminant, acting with the same potency as a therapeutic drug, induces PPARγ-dependent adipocyte differentiation in bone marrow MSCs. Activation of multiple nuclear receptor pathways by organotins may have significant implications for bone physiology.
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Affiliation(s)
- Susan C Yanik
- Department of Environmental Health, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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Stunes AK, Westbroek I, Gustafsson BI, Fossmark R, Waarsing JH, Eriksen EF, Petzold C, Reseland JE, Syversen U. The peroxisome proliferator-activated receptor (PPAR) alpha agonist fenofibrate maintains bone mass, while the PPAR gamma agonist pioglitazone exaggerates bone loss, in ovariectomized rats. BMC Endocr Disord 2011; 11:11. [PMID: 21615901 PMCID: PMC3127763 DOI: 10.1186/1472-6823-11-11] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Accepted: 05/26/2011] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Activation of peroxisome proliferator-activated receptor (PPAR)gamma is associated with bone loss and increased fracture risk, while PPARalpha activation seems to have positive skeletal effects. To further explore these effects we have examined the effect of the PPARalpha agonists fenofibrate and Wyeth 14643, and the PPARgamma agonist pioglitazone, on bone mineral density (BMD), bone architecture and biomechanical strength in ovariectomized rats. METHODS Fifty-five female Sprague-Dawley rats were assigned to five groups. One group was sham-operated and given vehicle (methylcellulose), the other groups were ovariectomized and given vehicle, fenofibrate, Wyeth 14643 and pioglitazone, respectively, daily for four months. Whole body and femoral BMD were measured by dual X-ray absorptiometry (DXA), and biomechanical testing of femurs, and micro-computed tomography (microCT) of the femoral shaft and head, were performed. RESULTS Whole body and femoral BMD were significantly higher in sham controls and ovariectomized animals given fenofibrate, compared to ovariectomized controls. Ovariectomized rats given Wyeth 14643, maintained whole body BMD at sham levels, while rats on pioglitazone had lower whole body and femoral BMD, impaired bone quality and less mechanical strength compared to sham and ovariectomized controls. In contrast, cortical volume, trabecular bone volume and thickness, and endocortical volume were maintained at sham levels in rats given fenofibrate. CONCLUSIONS The PPARalpha agonist fenofibrate, and to a lesser extent the PPARaplha agonist Wyeth 14643, maintained BMD and bone architecture at sham levels, while the PPARgamma agonist pioglitazone exaggerated bone loss and negatively affected bone architecture, in ovariectomized rats.
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Affiliation(s)
- Astrid K Stunes
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, Norway
| | - Irene Westbroek
- Internal Medicine and Orthopaedics, Erasmus MC, Rotterdam, the Netherlands
| | - Björn I Gustafsson
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, Norway
- Department of Gastroenterology, St Olav's University Hospital HF, Trondheim, Norway
| | - Reidar Fossmark
- Department of Gastroenterology, St Olav's University Hospital HF, Trondheim, Norway
| | - Jan H Waarsing
- Internal Medicine and Orthopaedics, Erasmus MC, Rotterdam, the Netherlands
| | - Erik F Eriksen
- Hormone Laboratory, Aker University Hospital, Oslo, Norway
| | - Christiane Petzold
- Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, Oslo, Norway
| | - Janne E Reseland
- Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, Oslo, Norway
| | - Unni Syversen
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, Norway
- Department of Endocrinology, St Olav's University Hospital HF, Trondheim, Norway
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Castillero E, Nieto-Bona MP, Fernández-Galaz C, Martín AI, López-Menduiña M, Granado M, Villanúa MA, López-Calderón A. Fenofibrate, a PPAR{alpha} agonist, decreases atrogenes and myostatin expression and improves arthritis-induced skeletal muscle atrophy. Am J Physiol Endocrinol Metab 2011; 300:E790-9. [PMID: 21304067 DOI: 10.1152/ajpendo.00590.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Arthritis is a chronic inflammatory illness that induces cachexia, which has a direct impact on morbidity and mortality. Fenofibrate, a selective PPARα activator prescribed to treat human dyslipidemia, has been reported to decrease inflammation in rheumatoid arthritis patients. The aim of this study was to elucidate whether fenofibrate is able to ameliorate skeletal muscle wasting in adjuvant-induced arthritis, an experimental model of rheumatoid arthritis. On day 4 after adjuvant injection, control and arthritic rats were treated with 300 mg/kg fenofibrate until day 15, when all rats were euthanized. Fenofibrate decreased external signs of arthritis and liver TNFα and blocked arthritis-induced decreased in PPARα expression in the gastrocnemius muscle. Arthritis decreased gastrocnemius weight, which results from a decrease in cross-section area and myofiber size, whereas fenofibrate administration to arthritic rats attenuated the decrease in both gastrocnemius weight and fast myofiber size. Fenofibrate treatment prevented arthritis-induced increase in atrogin-1 and MuRF1 expression in the gastrocnemius. Neither arthritis nor fenofibrate administration modify Akt-FoxO3 signaling. Myostatin expression was not modified by arthritis, but fenofibrate decreased myostatin expression in the gastrocnemius of arthritic rats. Arthritis increased muscle expression of MyoD, PCNA, and myogenin in the rats treated with vehicle but not in those treated with fenofibrate. The results indicate that, in experimental arthritis, fenofibrate decreases skeletal muscle atrophy through inhibition of the ubiquitin-proteasome system and myostatin.
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Affiliation(s)
- Estíbaliz Castillero
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense, Madrid, Spain 28040.
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Zhong X, Xiu LL, Wei GH, Liu YY, Su L, Cao XP, Li YB, Xiao HP. Bezafibrate enhances proliferation and differentiation of osteoblastic MC3T3-E1 cells via AMPK and eNOS activation. Acta Pharmacol Sin 2011; 32:591-600. [PMID: 21499286 DOI: 10.1038/aps.2011.15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To investigate the effects of bezafibrate on the proliferation and differentiation of osteoblastic MC3T3-E1 cells, and to determine the signaling pathway underlying the effects. METHODS MC3T3-E1 cells, a mouse osteoblastic cell line, were used. Cell viability and proliferation were examined using MTT assay and colorimetric BrdU incorporation assay, respectively. NO production was evaluated using the Griess reagent. The mRNA expression of ALP, collagen I, osteocalcin, BMP-2, and Runx-2 was measured using real-time PCR. Western blot analysis was used to detect the expression of AMPK and eNOS proteins. RESULTS Bezafibrate increased the viability and proliferation of MC3T3-E1 cells in a dose- and time-dependent manner. Bezafibrate (100 μmol/L) significantly enhanced osteoblastic mineralization and expression of the differentiation markers ALP, collagen I and osteocalcin. Bezafibrate (100 μmol/L) increased phosphorylation of AMPK and eNOS, which led to an increase of NO production by 4.08-fold, and upregulating BMP-2 and Runx-2 mRNA expression. These effects could be blocked by AMPK inhibitor compound C (5 μmol/L), or the PPARβ inhibitor GSK0660 (0.5 μmol/L), but not by the PPARα inhibitor MK886 (10 μmol/L). Furthermore, GSK0660, compound C, or N(G)-nitro-L-arginine methyl ester hydrochloride (L-NAME, 1 mmol/L) could reverse the stimulatory effects of bezafibrate (100 μmol/L) on osteoblast proliferation and differentiation, whereas MK886 only inhibited bezafibrate-induced osteoblast proliferation. CONCLUSION Bezafibrate stimulates proliferation and differentiation of MC3T3-E1 cells, mainly via a PPARβ-dependent mechanism. The drug might be beneficial for osteoporosis by promoting bone formation.
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