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Shiwaku Y, Okawa H, Suzuki I, Sakai S, Egusa H, Suzuki O. Induced pluripotent stem cell-derived neural stem cells promote bone formation in mice with calvarial defects. Acta Biomater 2024:S1742-7061(24)00506-3. [PMID: 39241820 DOI: 10.1016/j.actbio.2024.08.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 07/27/2024] [Accepted: 08/29/2024] [Indexed: 09/09/2024]
Abstract
Nerve-derived factors have attracted attention in bone regeneration therapy due to their ability to promote bone regeneration and nerve innervation. Mesenchymal stem cells transported to target sites promote osteogenesis. However, there are few reports on the effects of neural stem cells on bone regeneration. Therefore, the aim of this study was to investigate the role of neural stem cells in osteogenesis. Here, embryoid bodies (EB) or primary neurospheres (1NS) were generated using mouse induced pluripotent stem cells (iPS cells), which were then seeded onto gelatin (Gel) sponges. The seeded Gel sponges were then transplanted into mouse calvarial bone defects. We noted that 1NS-seeded Gel promoted bone regeneration and the presence of TRAP-positive cells, whereas the EB-seeded Gel did not. RNA-sequencing of the 1NS-seeded and EB seeded Gels showed an upregulation of the TGF-β signaling pathway in the 1NS-seeded Gel group. Immunostaining confirmed the presence of Id3 positive cells in mice with bone defects treated with the 1NS-seeded Gel. These findings suggest that the transplantation of neural stem cells may contribute to the promotion of bone regeneration. STATEMENT OF SIGNIFICANCE: This study aimed to investigate whether neural stem cells, when seeded in gelatin sponges, promoted bone regeneration. It has been well documented that bone is tightly linked with the nervous systems. Bioscaffolds comprising factors that promote innervation and bone regeneration have been investigated for use in bone therapy. However, there is limited research on the use of neural stem cells for promoting bone formation. To assess this relationship, we conducted both in vivo and in vitro assays to determine whether neural stem cells promoted bone formation. We noted that primary neurospheres-seeded gelatin sponges promoted bone formation significantly in mice with calvarial defects after four weeks. This study provides a novel approach of neural stem cells for bone therapy.
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Affiliation(s)
- Yukari Shiwaku
- Division of Craniofacial Function Engineering (Division of Biomaterials Science and Engineering), Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
| | - Hiroko Okawa
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, 980-8575, Japan
| | - Ikuro Suzuki
- Department of Electronics, Graduate School of Engineering, Tohoku Institute of Technology, Sendai 982-8577, Japan
| | - Susumu Sakai
- Division of Craniofacial Function Engineering (Division of Biomaterials Science and Engineering), Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan
| | - Hiroshi Egusa
- Division of Molecular and Regenerative Prosthodontics, Tohoku University Graduate School of Dentistry, Sendai, 980-8575, Japan
| | - Osamu Suzuki
- Division of Craniofacial Function Engineering (Division of Biomaterials Science and Engineering), Tohoku University Graduate School of Dentistry, Sendai 980-8575, Japan.
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Idelevich A, Sato K, Avihai B, Nagano K, Galien A, Rowe G, Gori F, Baron R. Both NPY-Expressing and CART-Expressing Neurons Increase Energy Expenditure and Trabecular Bone Mass in Response to AP1 Antagonism, But Have Opposite Effects on Bone Resorption. J Bone Miner Res 2020; 35:1107-1118. [PMID: 31995643 DOI: 10.1002/jbmr.3967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 12/26/2019] [Accepted: 01/16/2020] [Indexed: 01/20/2023]
Abstract
Energy metabolism and bone homeostasis share several neuronal regulatory pathways. Within the ventral hypothalamus (VHT), the orexigenic neurons co-express Agouti-related peptide (AgRP) and neuropeptide Y (NPY) and the anorexigenic neurons co-express, α-melanocyte stimulating hormone derived from proopiomelanocortin (POMC), and cocaine and amphetamine-regulated transcript (CART). These neurons regulate both processes, yet their relative contribution is unknown. Previously, using genetically targeted activator protein (AP1) alterations as a tool, we showed in adult mice that AgRP or POMC neurons are capable of inducing whole-body energy catabolism and bone accrual, with different effects on bone resorption. Here, we investigated whether co-residing neurons exert similar regulatory effects. We show that AP1 antagonists targeted to NPY-producing or CART-producing neurons in adult mice stimulate energy expenditure, reduce body weight gain and adiposity and promote trabecular bone formation and mass, yet again via different effects on bone resorption, as measured by serum level of carboxy-terminal collagen type I crosslinks (CTX). In addition, AP1 antagonists promote neurite expansion, increasing neurite number, length, and surface area in primary hypothalamic neuronal cultures. Overall, our data demonstrate that the orexigenic NPY and anorexigenic CART neurons both have the capacity to stimulate energy burning state and increase bone mass. © 2020 American Society for Bone and Mineral Research.
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Affiliation(s)
- Anna Idelevich
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Kazusa Sato
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Byron Avihai
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Kenichi Nagano
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Antonin Galien
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Glenn Rowe
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Francesca Gori
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Roland Baron
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
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Idelevich A, Sato K, Nagano K, Rowe G, Gori F, Baron R. ΔFosB Requires Galanin, but not Leptin, to Increase Bone Mass via the Hypothalamus, but both are needed to increase Energy expenditure. J Bone Miner Res 2019; 34:1707-1720. [PMID: 30998833 PMCID: PMC6744351 DOI: 10.1002/jbmr.3741] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 03/22/2019] [Accepted: 04/05/2019] [Indexed: 01/29/2023]
Abstract
Energy metabolism and bone homeostasis share several regulatory pathways. The AP1 transcription factor ΔFosB and leptin both regulate energy metabolism and bone, yet whether their pathways intersect is not known. Transgenic mice overexpressing ΔFosB under the control of the Enolase 2 (ENO2) promoter exhibit high bone mass, high energy expenditure, low fat mass, and low circulating leptin levels. Because leptin is a regulator of bone and ΔFosB acts on leptin-responsive ventral hypothalamic (VHT) neurons to induce bone anabolism, we hypothesized that regulation of leptin may contribute to the central actions of ΔFosB in the VHT. To address this question, we used adeno-associated virus (AAV) expression of ΔFosB in the VHT of leptin-deficient ob/ob mice and genetic crossing of ENO2-ΔFosB with ob/ob mice. In both models, leptin deficiency prevented ΔFosB-triggered reduction in body weight, increase in energy expenditure, increase in glucose utilization, and reduction in pancreatic islet size. In contrast, leptin deficiency failed to prevent ΔFosB-triggered increase in bone mass. Unlike leptin deficiency, galanin deficiency blocked both the metabolic and the bone ΔFosB-induced effects. Overall, our data demonstrate that, while the catabolic energy metabolism effects of ΔFosB require intact leptin and galanin signaling, the bone mass-accruing effects of ΔFosB require galanin but are independent of leptin. © 2019 American Society for Bone and Mineral Research.
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Affiliation(s)
- Anna Idelevich
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Kazusa Sato
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Kenichi Nagano
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Glenn Rowe
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Francesca Gori
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Roland Baron
- Department of Medicine, Harvard Medical School and Endocrine Unit, Massachusetts General Hospital, and Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
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Idelevich A, Baron R. Brain to bone: What is the contribution of the brain to skeletal homeostasis? Bone 2018; 115:31-42. [PMID: 29777919 PMCID: PMC6110971 DOI: 10.1016/j.bone.2018.05.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/15/2018] [Accepted: 05/15/2018] [Indexed: 12/13/2022]
Abstract
The brain, which governs most, if not all, physiological functions in the body, from the complexities of cognition, learning and memory, to the regulation of basal body temperature, heart rate and breathing, has long been known to affect skeletal health. In particular, the hypothalamus - located at the base of the brain in close proximity to the medial eminence, where the blood-brain-barrier is not as tight as in other regions of the brain but rather "leaky", due to fenestrated capillaries - is exposed to a variety of circulating body cues, such as nutrients (glucose, fatty acids, amino acids), and hormones (insulin, glucagon, leptin, adiponectin) [1-3].Information collected from the body via these peripheral cues is integrated by hypothalamic sensing neurons and glial cells [4-7], which express receptors for these nutrients and hormones, transforming these cues into physiological outputs. Interestingly, many of the same molecules, including leptin, adiponectin and insulin, regulate both energy and skeletal homeostasis. Moreover, they act on a common set of hypothalamic nuclei and their residing neurons, activating endocrine and neuronal systems, which ultimately fine-tune the body to new physiological states. This review will focus exclusively on the brain-to-bone pathway, highlighting the most important anatomical sites within the brain, which are known to affect bone, but not covering the input pathways and molecules informing the brain of the energy and bone metabolic status, covered elsewhere [8-10]. The discussion in each section will present side by side the metabolic and bone-related functions of hypothalamic nuclei, in an attempt to answer some of the long-standing questions of whether energy is affected by bone remodeling and homeostasis and vice versa.
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Affiliation(s)
- Anna Idelevich
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA
| | - Roland Baron
- Department of Medicine, Harvard Medical School and Endocrine Unit MGH, Division of Bone and Mineral Metabolism, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA.
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Idelevich A, Sato K, Nagano K, Rowe G, Gori F, Baron R. Neuronal hypothalamic regulation of body metabolism and bone density is galanin dependent. J Clin Invest 2018; 128:2626-2641. [PMID: 29596063 DOI: 10.1172/jci99350] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 03/20/2018] [Indexed: 12/13/2022] Open
Abstract
In the brain, the ventral hypothalamus (VHT) regulates energy and bone metabolism. Whether this regulation uses the same or different neuronal circuits is unknown. Alteration of AP1 signaling in the VHT increases energy expenditure, glucose utilization, and bone density, yet the specific neurons responsible for each or all of these phenotypes are not identified. Using neuron-specific, genetically targeted AP1 alterations as a tool in adult mice, we found that agouti-related peptide-expressing (AgRP-expressing) or proopiomelanocortin-expressing (POMC-expressing) neurons, predominantly present in the arcuate nucleus (ARC) within the VHT, stimulate whole-body energy expenditure, glucose utilization, and bone formation and density, although their effects on bone resorption differed. In contrast, AP1 alterations in steroidogenic factor 1-expressing (SF1-expressing) neurons, present in the ventromedial hypothalamus (VMH), increase energy but decrease bone density, suggesting that these effects are independent. Altered AP1 signaling also increased the level of the neuromediator galanin in the hypothalamus. Global galanin deletion (VHT galanin silencing using shRNA) or pharmacological galanin receptor blockade counteracted the observed effects on energy and bone. Thus, AP1 antagonism reveals that AgRP- and POMC-expressing neurons can stimulate body metabolism and increase bone density, with galanin acting as a central downstream effector. The results obtained with SF1-expressing neurons, however, indicate that bone homeostasis is not always dictated by the global energy status, and vice versa.
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Li H, Wei X, Yang J, Dong D, Huang Y, Lan X, Plath M, Lei C, Qi X, Bai Y, Chen H. Developmental transcriptome profiling of bovine muscle tissue reveals an abundant GosB that regulates myoblast proliferation and apoptosis. Oncotarget 2018; 8:32083-32100. [PMID: 28404879 PMCID: PMC5458270 DOI: 10.18632/oncotarget.16644] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 02/28/2017] [Indexed: 01/20/2023] Open
Abstract
The formation of bovine skeletal muscle involves complex developmental and physiological processes that play a vital role in determining the quality of beef; however, the regulatory mechanisms underlying differences in meat quality are largely unknown. We conducted transcriptome analysis of bovine muscle tissues to compare gene expression profiles between embryonic and adult stages. Total RNAs from skeletal muscle of Qinchuan cattle at fetal and adult stages were used to construct libraries for Illumina next-generation sequencing using the Ribo-Zero RNA sequencing (RNA-Seq) method. We found a total of 19,695 genes to be expressed in fetal and adult stages, whereby 3,299 were expressed only in fetal, and 433 only in adult tissues. We characterized the role of a candidate gene (GosB), which was highly (but differentially) expressed in embryonic and adult skeletal muscle tissue. GosB increased the number of myoblasts in the S-phase of the cell cycle, and decreased the proportion of cells in the G0/G1 phase. GosB promoted the proliferation of myoblasts and protected them from apoptosis via regulating Bcl-2 expression and controlling the intracellular calcium concentration. Modulation of GosB expression in muscle tissue may emerge as a potential target in breeding strategies attempting to alter myoblast numbers in cattle.
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Affiliation(s)
- Hui Li
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xuefeng Wei
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jiameng Yang
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Dong Dong
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Yongzhen Huang
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xianyong Lan
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Martin Plath
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Chuzhao Lei
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xinglei Qi
- Bureau of Animal Husbandry of Biyang County, Biyang, Henan 463700, China
| | - Yueyu Bai
- Animal Health Supervision of Henan Province, Bureau of Animal Husbandry of Henan province, Zhengzhou, Henan 450008, China
| | - Hong Chen
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
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GosB Inhibits Triacylglycerol Synthesis and Promotes Cell Survival in Mouse Mammary Epithelial Cells. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7394869. [PMID: 29181403 PMCID: PMC5664265 DOI: 10.1155/2017/7394869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/26/2017] [Accepted: 09/07/2017] [Indexed: 11/18/2022]
Abstract
It has been demonstrated that the activator protein related transcription factor Finkel-Biskis-Jinkins murine osteosarcoma B (GosB) is involved in preadipocyte differentiation and triacylglycerol synthesis. However, the role of GosB in regulating the synthesis of milk fatty acid in mouse mammary glands remains unclear. This research uncovered potentially new roles of GosB in suppressing milk fatty acid synthesis. Results revealed that GosB had the highest expression in lung tissue and showed a higher expression level during nonlactation than during lactation. GosB inhibited the expression of fatty acid synthase (FASN), stearoyl-CoA desaturase (SCD), fatty acid binding protein 4 (FABP4), diacylglycerol acyltransferase 1 (DGAT1), perilipin 2 (PLIN2), perilipin 3 (PLIN3), and C/EBPα in mouse mammary gland epithelial cells (MEC). In addition, GosB reduced cellular triglyceride content and the accumulation of lipid droplets; in particular, GosB enhanced saturated fatty acid concentration (C16:0 and C18:0). The PPARγ agonist, rosiglitazone (ROSI), promoted apoptosis and inhibited cell proliferation. GosB increased the expression of Bcl-2 and protected MEC from ROSI-induced apoptosis. Furthermore, MECs were protected from apoptosis through the GosB regulation of intracellular calcium concentrations. These findings suggest that GosB may regulate mammary epithelial cells milk fat synthesis and apoptosis via PPARγ in mouse mammary glands.
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Hypothalamic ΔFosB prevents age-related metabolic decline and functions via SNS. Aging (Albany NY) 2017; 9:353-369. [PMID: 28121620 PMCID: PMC5361668 DOI: 10.18632/aging.101157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 01/15/2017] [Indexed: 12/31/2022]
Abstract
The ventral hypothalamus (VHT) integrates several physiological cues to maintain glucose homeostasis and energy balance. Aging is associated with increased glucose intolerance but the underlying mechanisms responsible for age-related metabolic decline, including neuronal signaling in the VHT, remain elusive. We have shown that mice with VHT-targeted overexpression of ∆FosB, a splice variant of the AP1 transcription factor FosB, exhibit increased energy expenditure, leading to decreased adiposity. Here, we show that VHT-targeted overexpression of ∆FosB also improves glucose tolerance, increases insulin sensitivity in target organs and thereby suppresses insulin secretion. These effects are also observed by the overexpression of dominant negative JunD, demonstrating that they occur via AP1 antagonism within the VHT. Furthermore, the improved glucose tolerance and insulin sensitivity persisted in aged animals overexpressing ∆FosB in the VHT. These beneficial effects on glucose metabolism were abolished by peripheral sympathectomy and α-adrenergic, but not β-adrenergic, blockade. Taken together, our results show that antagonizing AP1 transcription activity in the VHT leads to a marked improvement in whole body glucose homeostasis via activation of the SNS, conferring protection against age-related impairment in glucose metabolism. These findings may open novel avenues for therapeutic intervention in diabetes and age-related glucose intolerance.
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Wei X, Li H, Zhao G, Yang J, Li L, Huang Y, Lan X, Ma Y, Hu L, Zheng H, Chen H. ΔFosB regulates rosiglitazone-induced milk fat synthesis and cell survival. J Cell Physiol 2017; 233:9284-9298. [PMID: 29154466 DOI: 10.1002/jcp.26218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 10/09/2017] [Indexed: 02/06/2023]
Abstract
Rosiglitazone induces adipogenesis in adipocyte and regulates cell survival and differentiation in number of cell types. However, whether PPARγ regulates the synthesis of milk fat and cell survival in goat mammary gland remains unknown. Rosiglitazone strongly enhanced cellular triacylglycerol content and accumulation of lipid droplet in goat mammary epithelial cells (GMEC). Furthermore, ΔFosB decreased the expression of PPARγ at both mRNA and protein levels, and rosiglitazone-induced milk fat synthesis was abolished by ΔFosB overexpression. ΔFosB reduced milk fat synthesis and enhanced saturated fatty acid concentration. Rosiglitazone increased the number of GMEC in G0/G1 phase and inhibited cell proliferation, and these effects were improved by overexpression of ΔFosB. ΔFosB was found to promote the expression of Bcl-2 and suppress the expression of Bax, and protected GMEC from apoptosis induced by rosiglitazone. Intracellular calcium trafficking assay revealed that rosiglitazone markedly increased intracellular calcium concentration. ΔFosB protected GMEC from apoptosis induced by intracellular Ca2+ overload. ΔFosB increased MMP-9 gelatinolytic activity. SB-3CT, an MMP-9 inhibitor, suppressed the expression of Bcl-2, and increased intracellular calcium levels, and this effect was abolished by ΔFosB overexpression. SB-3CT induced GMEC apoptosis and this effect was inhibited by ΔFosB overexpression. These findings suggest that ΔFosB regulates rosiglitazone-induced milk fat synthesis and cell survival. Therefore, ΔFosB may be an important checkpoint to control milk fat synthesis and cell apoptosis.
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Affiliation(s)
- Xuefeng Wei
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China.,College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Hui Li
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China.,College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Guangwei Zhao
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Jiameng Yang
- College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Lihui Li
- College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Yongzhen Huang
- College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Xianyong Lan
- College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Yun Ma
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Linyong Hu
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, China
| | - Huiling Zheng
- College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
| | - Hong Chen
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China.,College of Life Sciences, Xinyang Normal University, Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang, Henan, China
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Zhu X, Zhou Y, Tao R, Zhao J, Chen J, Liu C, Xu Z, Bao G, Zhang J, Chen M, Shen J, Cheng C, Zhang D. Upregulation of PTP1B After Rat Spinal Cord Injury. Inflammation 2016; 38:1891-902. [PMID: 25894283 DOI: 10.1007/s10753-015-0169-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Protein tyrosine phosphatase 1B (PTP1B), a member of the protein tyrosine phosphatase family, attaches to the endoplasmic reticulum (ER) via its C-terminal tail. Previous studies have reported that PTP1B participates in various signal transduction pathways in many human diseases, including diabetes, cancers, osteoporosis, and obesity. It also plays an important role in the ER stress. ER stress induced by spinal cord injury (SCI) was reported to result in cell apoptosis. Till now, the role of PTP1B in the injury of the central nervous system remains unknown. In the present study, we built an adult rat SCI model to investigate the potential role of PTP1B in SCI. Western blot analysis detected a notable alteration of PTP1B expression after SCI. Immunohistochemistry indicated that PTP1B expressed at a low level in the normal spinal cord and greatly increased after SCI. Double immunofluorescence staining revealed that PTP1B immunoreactivity was predominantly increased in neurons following SCI. In addition, SCI resulted in a significant alteration in the level of active caspase-3, caspase-12, and 153/C/EBP homologous transcription factor protein, which were correlated with the upregulation of PTP1B. Co-localization of PTP1B/active caspase-3 was also detected in neurons. Taken together, our findings elucidated the PTP1B expression in the SCI for the first time. These results suggested that PTP1B might be deeply involved in the injury response and probably played an important role in the neuro-pathological process of SCI.
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Affiliation(s)
- Xinhui Zhu
- Department of Osteology, The Second Affiliated Hospital, Nantong University, Nantong, 226001, People's Republic of China
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Abstract
There are well-established associations between diabetes and fracture risk and yet the mechanism underlying these associations are controversial. Guided by a series of mouse studies, a specific form of the bone protein, osteocalcin, was proposed to be the mechanistic link between these two chronic diseases. Translation to humans initially appeared elusive in part because serum concentrations of osteocalcin are a biomarker of bone turnover and not necessarily specific to the biology of this protein. The suitability of the mouse model for the study of osteocalcin as a therapeutic target also appears ambiguous. With greater discrimination of the different forms of osteocalcin present in circulation and inclusion of multiple measures of bone turnover, evidence currently does not support osteocalcin as a protein critical to the diabetes and fracture association in humans.
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Affiliation(s)
- Sarah L Booth
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA, 02111, USA,
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Rowe GC, Vialou V, Sato K, Saito H, Yin M, Green TA, Lotinun S, Kveiborg M, Horne WC, Nestler EJ, Baron R. Energy expenditure and bone formation share a common sensitivity to AP-1 transcription in the hypothalamus. J Bone Miner Res 2012; 27:1649-58. [PMID: 22461201 PMCID: PMC3399943 DOI: 10.1002/jbmr.1618] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The regulation of bone and fat homeostasis and its relationship to energy expenditure has recently been the focus of increased attention because of its potential relevance to osteoporosis, obesity, and diabetes. Although central effectors within the hypothalamus have been shown to contribute to the regulation of both energy balance and bone homeostasis, little is known of the underlying mechanisms, including the possible involvement of transcriptional factors within the hypothalamus. Transgenic mice overexpressing ΔFosB, a splice variant of the AP-1 transcription factor FosB with mixed agonist-antagonistic properties, have increased energy expenditure and bone mass. Because these mice express ΔFosB in bone, fat, and hypothalamus, we sought to determine 1) whether overexpression of ΔFosB within the hypothalamus was sufficient to regulate energy expenditure and whether it would also regulate bone mass, and 2) whether these effects were the result of antagonism to AP-1. Our results show that stereotactic injection of an adeno-associated virus vector to restrict overexpression of ΔFosB to the ventral hypothalamus of wild-type mice induced a profound increase in both energy expenditure and bone formation and bone mass. This effect was phenocopied, at an even stronger level, by overexpression of a dominant-negative DNJunD, a pure AP-1 antagonist. Taken together, these results suggest that downregulation of AP-1 activity in the hypothalamus profoundly increases energy expenditure and bone formation, leading to both a decrease in adipose mass and an increase in bone mass. These findings may have physiological implications because ΔFosB is expressed and regulated in the hypothalamus.
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Affiliation(s)
- Glenn C Rowe
- Department of Medicine, Harvard Medical School, Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
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Wrann CD, Eguchi J, Bozec A, Xu Z, Mikkelsen T, Gimble J, Nave H, Wagner EF, Ong SE, Rosen ED. FOSL2 promotes leptin gene expression in human and mouse adipocytes. J Clin Invest 2012; 122:1010-21. [PMID: 22326952 DOI: 10.1172/jci58431] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 01/04/2012] [Indexed: 12/16/2022] Open
Abstract
The adipocyte-derived hormone leptin is a critical regulator of many physiological functions, ranging from satiety to immunity. Surprisingly, very little is known about the transcriptional pathways that regulate adipocyte-specific expression of leptin. Here, we report studies in which we pursued a strategy integrating BAC transgenic reporter mice, reporter assays, and chromatin state mapping to locate an adipocyte-specific cis-element upstream of the leptin (LEP) gene in human fat cells. Quantitative proteomics with affinity enrichment of protein-DNA complexes identified the transcription factor FOS-like antigen 2 (FOSL2) as binding specifically to the identified region, a result that was confirmed by ChIP. Knockdown of FOSL2 in human adipocytes decreased LEP expression, and overexpression of Fosl2 increased Lep expression in mouse adipocytes. Moreover, the elevated LEP expression observed in obesity correlated well with increased FOSL2 levels in mice and humans, and adipocyte-specific genetic deletion of Fosl2 in mice reduced Lep expression. Taken together, these data identify FOSL2 as a critical regulator of leptin expression in adipocytes.
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Affiliation(s)
- Christiane D Wrann
- Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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14
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Tamboli RA, Hajri T, Jiang A, Marks-Shulman PA, Williams DB, Clements RH, Melvin W, Bowen BP, Shyr Y, Abumrad NN, Flynn CR. Reduction in inflammatory gene expression in skeletal muscle from Roux-en-Y gastric bypass patients randomized to omentectomy. PLoS One 2011; 6:e28577. [PMID: 22194858 PMCID: PMC3241684 DOI: 10.1371/journal.pone.0028577] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Accepted: 11/10/2011] [Indexed: 12/19/2022] Open
Abstract
Objectives To examine the effects of Roux-en-Y gastric bypass (RYGB) surgery with and without laparoscopic removal of omental fat (omentectomy) on the temporal gene expression profiles of skeletal muscle. Design Previously reported were the whole-body metabolic effects of a randomized, single-blinded study in patients receiving RYGB surgery stratified to receive or not receive omentectomy. In this follow up study we report on changes in skeletal muscle gene expression in a subset of 21 patients, for whom biopsies were collected preoperatively and at either 6 months or 12 months postoperatively. Methodology/Principal Findings RNA isolated from skeletal muscle biopsies of 21 subjects (8 without omentectomy and 13 with omentectomy) taken before RYGB or at 6 and 12 months postoperatively were subjected to gene expression profiling via Exon 1.0 S/T Array and Taqman Low Density Array. Robust Multichip Analysis and gene enrichment data analysis revealed 84 genes with at least a 4-fold expression difference after surgery. At 6 and 12 months the RYGB with omentectomy group displayed a greater reduction in the expression of genes associated with skeletal muscle inflammation (ANKRD1, CDR1, CH25H, CXCL2, CX3CR1, IL8, LBP, NFIL3, SELE, SOCS3, TNFAIP3, and ZFP36) relative to the RYGB non-omentectomy group. Expressions of IL6 and CCL2 were decreased at all postoperative time points. There was differential expression of genes driving protein turnover (IGFN1, FBXW10) in both groups over time and increased expression of PAAF1 in the non-omentectomy group at 12 months. Evidence for the activation of skeletal muscle satellite cells was inferred from the up-regulation of HOXC10. The elevated post-operative expression of 22 small nucleolar RNAs and the decreased expression of the transcription factors JUNB, FOS, FOSB, ATF3 MYC, EGR1 as well as the orphan nuclear receptors NR4A1, NR4A2, NR4A3 suggest dramatic reorganizations at both the cellular and genetic levels. Conclusions/Significance These data indicate that RYGB reduces skeletal muscle inflammation, and removal of omental fat further amplifies this response. Trial Registration ClinicalTrials.gov NCT00212160
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Affiliation(s)
- Robyn A. Tamboli
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Tahar Hajri
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Aixiang Jiang
- Department of Cancer Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Pamela A. Marks-Shulman
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - D. Brandon Williams
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Ronald H. Clements
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Willie Melvin
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Benjamin P. Bowen
- Department of GTL Bioenergy and Structural Biology, Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Yu Shyr
- Department of Cancer Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Naji N. Abumrad
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Charles Robb Flynn
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- * E-mail:
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15
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Vialou V, Cui H, Perello M, Mahgoub M, Yu HG, Rush AJ, Pranav H, Jung S, Yangisawa M, Zigman JM, Elmquist JK, Nestler EJ, Lutter M. A role for ΔFosB in calorie restriction-induced metabolic changes. Biol Psychiatry 2011; 70:204-7. [PMID: 21215388 PMCID: PMC3125466 DOI: 10.1016/j.biopsych.2010.11.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 11/03/2010] [Accepted: 11/15/2010] [Indexed: 10/18/2022]
Abstract
BACKGROUND Calorie restriction (CR) induces long-term changes in motivation to eat highly palatable food and, in body weight regulation, through an unknown mechanism. METHODS After a period of CR and refeeding, mice were assessed by behavioral and metabolic studies and for levels of the transcription factor ΔFosB. The ΔFosB levels were then increased specifically in nucleus accumbens (NAc) with viral-mediated gene transfer, and behavioral and metabolic studies were conducted. RESULTS We show that accumulation of ΔFosB in the NAc shell after CR in mice corresponds to a period of increased motivation for high fat reward and reduced energy expenditure. Furthermore, ΔFosB overexpression in this region increases instrumental responding for a high fat reward via an orexin-dependent mechanism while also decreasing energy expenditure and promoting adiposity. CONCLUSIONS These results suggest that ΔFosB signaling in NAc mediates adaptive responses to CR.
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Affiliation(s)
- Vincent Vialou
- Fishberg Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029-6574
| | - Huxing Cui
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Mario Perello
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Melissa Mahgoub
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Hana G. Yu
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Augustus J. Rush
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Heena Pranav
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Saendy Jung
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Masashi Yangisawa
- Department of Molecular Genetics and the Howard Hughes Medical Institute, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Jeffrey M. Zigman
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Joel K. Elmquist
- Department of Internal Medicine, Division of Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, 75390
| | - Eric J. Nestler
- Fishberg Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029-6574
| | - Michael Lutter
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, 75390,To whom correspondence should be addressed. Phone: 214-645-2564. Fax: 214-645-2786.
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16
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Luther J, Driessler F, Megges M, Hess A, Herbort B, Mandic V, Zaiss MM, Reichardt A, Zech C, Tuckermann JP, Calkhoven CF, Wagner EF, Schett G, David JP. Elevated Fra-1 expression causes severe lipodystrophy. J Cell Sci 2011; 124:1465-76. [PMID: 21486951 DOI: 10.1242/jcs.079855] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A shift from osteoblastogenesis to adipogenesis is one of the underlying mechanisms of decreased bone mass and increased fat during aging. We now uncover a new role for the transcription factor Fra-1 in suppressing adipogenesis. Indeed, Fra1 (Fosl1) transgenic (Fra1tg) mice, which developed progressive osteosclerosis as a result of accelerated osteoblast differentiation, also developed a severe general lipodystrophy. The residual fat of these mice appeared immature and expressed lower levels of adipogenic markers, including the fatty acid transporter Cd36 and the CCAAT/enhancer binding protein Cebpa. Consequently accumulation of triglycerides and free fatty acids were detected in the serum of fasting Fra1tg mice. Fra-1 acts cell autonomously because the adipogenic differentiation of Fra1 transgenic primary osteoblasts was drastically reduced, and overexpression of Fra-1 in an adipogenic cell line blocked their differentiation into adipocytes. Strikingly, Cebpa was downregulated in the Fra-1-overexpressing cells and Fra-1 could bind to the Cebpa promoter and directly suppress its activity. Thus, our data add to the known common systemic control of fat and bone mass, a new cell-autonomous level of control of cell fate decision by which the osteogenic transcription factor Fra-1 opposes adipocyte differentiation by inhibiting C/EBPα.
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Affiliation(s)
- Julia Luther
- Department of Internal Medicine 3, University of Erlangen-Nuremberg, D91054 Erlangen, Germany
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17
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Hesse E, Saito H, Kiviranta R, Correa D, Yamana K, Neff L, Toben D, Duda G, Atfi A, Geoffroy V, Horne WC, Baron R. Zfp521 controls bone mass by HDAC3-dependent attenuation of Runx2 activity. ACTA ACUST UNITED AC 2010; 191:1271-83. [PMID: 21173110 PMCID: PMC3010073 DOI: 10.1083/jcb.201009107] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Runx2 is indispensable for osteoblast lineage commitment and early differentiation but also blocks osteoblast maturation, thereby causing bone loss in Runx2 transgenic mice. Zinc finger protein 521 (Zfp521) antagonizes Runx2 in vivo. Eliminating one Zfp521 allele mitigates the cleidocranial dysplasia-like phenotype of newborn Runx2(+/-) mice, whereas overexpressing Zfp521 exacerbates it. Overexpressing Zfp521 also reverses the severe osteopenia of adult Runx2 transgenic mice. Zfp521 binds to both Runx2 and histone deacetylase 3 (HDAC3), promotes their association, and antagonizes Runx2 transcriptional activity in an HDAC3-dependent manner. Mutating the Zfp521 zinc finger domains 6 and 26 reduces the binding of Zfp521 to Runx2 and inhibition of Runx2 activity. These data provide evidence that Zfp521 antagonizes Runx2 in vivo and thereby regulates two stages of osteoblast development, early during mesenchymal cell lineage commitment and later during osteoblast maturation. Thus, the balance and molecular interplay between Zfp521 and Runx2 contribute to the control of osteoblast differentiation, skeletal development, and bone homeostasis.
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Affiliation(s)
- Eric Hesse
- Department of Medicine, Harvard Medical School, Harvard School of Dental Medicine, Harvard University, Boston, MA 02115, USA
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18
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Nishikawa K, Nakashima T, Takeda S, Isogai M, Hamada M, Kimura A, Kodama T, Yamaguchi A, Owen MJ, Takahashi S, Takayanagi H. Maf promotes osteoblast differentiation in mice by mediating the age-related switch in mesenchymal cell differentiation. J Clin Invest 2010; 120:3455-65. [PMID: 20877012 DOI: 10.1172/jci42528] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 07/14/2010] [Indexed: 12/13/2022] Open
Abstract
Aging leads to the disruption of the homeostatic balance of multiple biological systems. In bone marrow multipotent mesenchymal cells undergo differentiation into various anchorage-dependent cell types, including osteoblasts and adipocytes. With age as well as with treatment of antidiabetic drugs such as thiazolidinediones, mesenchymal cells favor differentiation into adipocytes, resulting in an increased number of adipocytes and a decreased number of osteoblasts, causing osteoporosis. The mechanism behind this differentiation switch is unknown. Here we show an age-related decrease in the expression of Maf in mouse mesenchymal cells, which regulated mesenchymal cell bifurcation into osteoblasts and adipocytes by cooperating with the osteogenic transcription factor Runx2 and inhibiting the expression of the adipogenic transcription factor Pparg. The crucial role of Maf in both osteogenesis and adipogenesis was underscored by in vivo observations of delayed bone formation in perinatal Maf(-/-) mice and an accelerated formation of fatty marrow associated with bone loss in aged Maf(+/-) mice. This study identifies a transcriptional mechanism for an age-related switch in cell fate determination and may provide a molecular basis for novel therapeutic strategies against age-related bone diseases.
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Affiliation(s)
- Keizo Nishikawa
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
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