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Baxter RC. Signaling Pathways of the Insulin-like Growth Factor Binding Proteins. Endocr Rev 2023; 44:753-778. [PMID: 36974712 PMCID: PMC10502586 DOI: 10.1210/endrev/bnad008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 01/25/2023] [Accepted: 03/15/2023] [Indexed: 03/29/2023]
Abstract
The 6 high-affinity insulin-like growth factor binding proteins (IGFBPs) are multifunctional proteins that modulate cell signaling through multiple pathways. Their canonical function at the cellular level is to impede access of insulin-like growth factor (IGF)-1 and IGF-2 to their principal receptor IGF1R, but IGFBPs can also inhibit, or sometimes enhance, IGF1R signaling either through their own post-translational modifications, such as phosphorylation or limited proteolysis, or by their interactions with other regulatory proteins. Beyond the regulation of IGF1R activity, IGFBPs have been shown to modulate cell survival, migration, metabolism, and other functions through mechanisms that do not appear to involve the IGF-IGF1R system. This is achieved by interacting directly or functionally with integrins, transforming growth factor β family receptors, and other cell-surface proteins as well as intracellular ligands that are intermediates in a wide range of pathways. Within the nucleus, IGFBPs can regulate the diverse range of functions of class II nuclear hormone receptors and have roles in both cell senescence and DNA damage repair by the nonhomologous end-joining pathway, thus potentially modifying the efficacy of certain cancer therapeutics. They also modulate some immune functions and may have a role in autoimmune conditions such as rheumatoid arthritis. IGFBPs have been proposed as attractive therapeutic targets, but their ubiquity in the circulation and at the cellular level raises many challenges. By understanding the diversity of regulatory pathways with which IGFBPs interact, there may still be therapeutic opportunities based on modulation of IGFBP-dependent signaling.
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Affiliation(s)
- Robert C Baxter
- Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital,St Leonards, NSW 2065, Australia
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2
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Thyroid Hormone Receptor Isoforms Alpha and Beta Play Convergent Roles in Muscle Physiology and Metabolic Regulation. Metabolites 2022; 12:metabo12050405. [PMID: 35629909 PMCID: PMC9145723 DOI: 10.3390/metabo12050405] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 11/30/2022] Open
Abstract
Skeletal muscle is a key energy-regulating organ, skilled in rapidly boosting the rate of energy production and substrate consumption following increased workload demand. The alteration of skeletal muscle metabolism is directly associated with numerous pathologies and disorders. Thyroid hormones (THs) and their receptors (TRs, namely, TRα and TRβ) exert pleiotropic functions in almost all cells and tissues. Skeletal muscle is a major THs-target tissue and alterations of THs levels have multiple influences on the latter. However, the biological role of THs and TRs in orchestrating metabolic pathways in skeletal muscle has only recently started to be addressed. The purpose of this paper is to investigate the muscle metabolic response to TRs abrogation, by using two different mouse models of global TRα- and TRβKO. In line with the clinical features of resistance to THs syndromes in humans, characterized by THRs gene mutations, both animal models of TRs deficiency exhibit developmental delay and mitochondrial dysfunctions. Moreover, using transcriptomic and metabolomic approaches, we found that the TRs–THs complex regulates the Fatty Acids (FAs)-binding protein GOT2, affecting FAs oxidation and transport in skeletal muscle. In conclusion, these results underline a new metabolic role of THs in governing muscle lipids distribution and metabolism.
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3
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Ran B, Wei F, Gong J, Xu H. Application and prospect of trabecular bone score in differentiated thyroid cancer patients receiving thyrotropin suppression therapy. Front Endocrinol (Lausanne) 2022; 13:1004962. [PMID: 36313757 PMCID: PMC9596913 DOI: 10.3389/fendo.2022.1004962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Thyroid-stimulating hormone (TSH) suppression therapy is one of the common treatments for most patients with differentiated thyroid cancer (DTC). Unfortunately, its detrimental effects on bone health are receiving increasing attention. It may increase the risk of osteoporosis and osteoporotic fractures. The trabecular bone score (TBS) is a relatively new gray-scale texture measurement parameter that reflects bone microarchitecture and bone strength and has been shown to independently predict fracture risk. We reviewed for the first time the scientific literature on the use of TBS in DTC patients on TSH suppression therapy and aim to analyze and compare the utility of TBS with bone mass strength (BMD) in the management of skeletal health and prediction of fracture risk. We screened a total of seven relevant publications, four of which were for postmenopausal female patients and three for all female patients. Overall, postmenopausal female patients with DTC had lower TBS and a significant reduction in TBS after receiving TSH suppression therapy, but their BMD did not appear to change significantly. In addition, TBS was also found to be an independent predictor of osteoporotic fracture risk in postmenopausal women with DTC receiving TSH suppression therapy. However, due to limitations in the number of studies and study populations, this evidence is not sufficient to fully demonstrate the adverse effects of TSH suppression therapy on patients' TBS or BMD and the efficacy of TBS, and subsequent larger and more case-cohort studies are needed to further investigate the relationship and application of TBS to TSH suppression therapy in terms of skeletal health impairment and fracture risk in DTC patients.
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Poreba E, Durzynska J. Nuclear localization and actions of the insulin-like growth factor 1 (IGF-1) system components: Transcriptional regulation and DNA damage response. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2020; 784:108307. [PMID: 32430099 DOI: 10.1016/j.mrrev.2020.108307] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/14/2022]
Abstract
Insulin-like growth factor (IGF) system stimulates growth, proliferation, and regulates differentiation of cells in a tissue-specific manner. It is composed of two insulin-like growth factors (IGF-1 and IGF-2), six insulin-like growth factor-binding proteins (IGFBPs), and two insulin-like growth factor receptors (IGF-1R and IGF-2R). IGF actions take place mostly through the activation of the plasma membrane-bound IGF-Rs by the circulating ligands (IGFs) released from the IGFBPs that stabilize their levels in the serum. This review focuses on the IGF-1 part of the system. The IGF-1 gene, which is expressed mainly in the liver as well as in other tissues, comprises six alternatively spliced exons that code for three protein isoforms (pro-IGF-1A, pro-IGF-1B, and pro-IGF-1C), which are processed to mature IGF-1 and E-peptides. The IGF-1R undergoes autophosphorylation, resulting in a signaling cascade involving numerous cytoplasmic proteins such as AKT and MAPKs, which regulate the expression of target genes. However, a more complex picture of the axis has recently emerged with all its components being translocated to the nuclear compartment. IGF-1R takes part in the regulation of gene expression by forming transcription complexes, modifying the activity of chromatin remodeling proteins, and participating in DNA damage tolerance mechanisms. Four IGFBPs contain a nuclear localization signal (NLS), which targets them to the nucleus, where they regulate gene expression (IGFBP-2, IGFBP-3, IGFBP-5, IGFBP-6) and DNA damage repair (IGFBP-3 and IGFBP-6). Last but not least, the IGF-1B isoform has been reported to be localized in the nuclear compartment. However, no specific molecular actions have been assigned to the nuclear pro-IGF-1B or its derivative EB peptide. Therefore, further studies are needed to shed light on their nuclear activity. These recently uncovered nuclear actions of different components of the IGF-1 axis are relevant in cancer cell biology and are discussed in this review.
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Affiliation(s)
- Elzbieta Poreba
- Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
| | - Julia Durzynska
- Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
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5
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Liso A, Capitanio N, Gerli R, Conese M. From fever to immunity: A new role for IGFBP-6? J Cell Mol Med 2018; 22:4588-4596. [PMID: 30117676 PMCID: PMC6156343 DOI: 10.1111/jcmm.13738] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 05/22/2018] [Indexed: 12/12/2022] Open
Abstract
Fever is a fundamental response to infection and a hallmark of inflammatory disease, which has been conserved and shaped through millions of years of natural selection. Although fever is able to stimulate both innate and adaptive immune responses, the very nature of all the molecular thermosensors, the timing and the detailed mechanisms translating a physical trigger into a fundamental biological response are incompletely understood. Here we discuss the consequence of hyperthermic stress in dendritic cells (DCs), and how the sole physical input is sensed as an alert stimulus triggering a complex transition in a very narrow temporal window. Importantly, we review recent findings demonstrating the significant and specific changes discovered in gene expression and in the metabolic phenotype associated with hyperthermia in DCs. Furthermore, we discuss the results that support a model based on a thermally induced autocrine signalling, which rewires and sets a metabolism checkpoint linked to immune activation of dendritic cells. Importantly, in this context, we highlight the novel regulatory functions discovered for IGFBP‐6 protein: induction of chemotaxis; capacity to increase oxidative burst and degranulation of neutrophils, ability to induce metabolic changes in DCs. Finally, we discuss the role of IGFBP‐6 in autoimmune disease and how novel mechanistic insights could lead to exploit thermal stress‐related mechanisms in the context of cancer therapy.
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Affiliation(s)
- Arcangelo Liso
- Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Nazzareno Capitanio
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Roberto Gerli
- Department of Medicine, University of Perugia, Perugia, Italy
| | - Massimo Conese
- Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
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6
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Gouveia CHA, Miranda-Rodrigues M, Martins GM, Neofiti-Papi B. Thyroid Hormone and Skeletal Development. VITAMINS AND HORMONES 2018; 106:383-472. [PMID: 29407443 DOI: 10.1016/bs.vh.2017.06.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Thyroid hormone (TH) is essential for skeletal development from the late fetal life to the onset of puberty. During this large window of actions, TH has key roles in endochondral and intramembranous ossifications and in the longitudinal bone growth. There is evidence that TH acts directly in skeletal cells but also indirectly, specially via the growth hormone/insulin-like growth factor-1 axis, to control the linear skeletal growth and maturation. The presence of receptors, plasma membrane transporters, and activating and inactivating enzymes of TH in skeletal cells suggests that direct actions of TH in these cells are crucial for skeletal development, which has been confirmed by several in vitro and in vivo studies, including mouse genetic studies, and clinical studies in patients with resistance to thyroid hormone due to dominant-negative mutations in TH receptors. This review examines progress made on understanding the mechanisms by which TH regulates the skeletal development.
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Affiliation(s)
- Cecilia H A Gouveia
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil; Experimental Pathophysiology Program, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
| | | | - Gisele M Martins
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil; Experimental Pathophysiology Program, School of Medicine, University of São Paulo, São Paulo, SP, Brazil; Federal University of Espírito Santo, Vitória, ES, Brazil
| | - Bianca Neofiti-Papi
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil; Experimental Pathophysiology Program, School of Medicine, University of São Paulo, São Paulo, SP, Brazil
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7
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Sanada F, Taniyama Y, Muratsu J, Otsu R, Shimizu H, Rakugi H, Morishita R. IGF Binding Protein-5 Induces Cell Senescence. Front Endocrinol (Lausanne) 2018; 9:53. [PMID: 29515523 PMCID: PMC5826077 DOI: 10.3389/fendo.2018.00053] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cellular senescence is the complex process of deterioration that drives the aging of an organism, resulting in the progressive loss of organ function and eventually phenotypic aging. Senescent cells undergo irreversible growth arrest, usually by inducing telomere shortening. Alternatively, senescence may also occur prematurely in response to various stress stimuli, such as oxidative stress, DNA damage, or activated oncogenes. Recently, it has been shown that IGF binding protein-5 (IGFBP-5) with the induction of the tumor suppressor p53 is upregulated during cellular senescence. This mechanism mediates interleukin-6/gp130-induced premature senescence in human fibroblasts, irradiation-induced premature senescence in human endothelial cells (ECs), and replicative senescence in human ECs independent of insulin-like growth factor I (IGF-I) and IGF-II. Additionally, a link between IGFBP-5, hyper-coagulation, and inflammation, which occur with age, has been implicated. Thus, IGFBP-5 seems to play decisive roles in controlling cell senescence and cell inflammation. In this review, we describe the accumulating evidence for this role of IGFBP-5 including our new finding.
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Affiliation(s)
- Fumihiro Sanada
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- *Correspondence: Fumihiro Sanada, ; Ryuichi Morishita,
| | - Yoshiaki Taniyama
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Jun Muratsu
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Rei Otsu
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Hideo Shimizu
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Hiromi Rakugi
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Ryuichi Morishita
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- *Correspondence: Fumihiro Sanada, ; Ryuichi Morishita,
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8
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Beattie J, Al-Khafaji H, Noer PR, Alkharobi HE, Alhodhodi A, Meade J, El-Gendy R, Oxvig C. Insulin- like Growth Factor-Binding Protein Action in Bone Tissue: A Key Role for Pregnancy- Associated Plasma Protein-A. Front Endocrinol (Lausanne) 2018; 9:31. [PMID: 29503631 PMCID: PMC5820303 DOI: 10.3389/fendo.2018.00031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 01/23/2018] [Indexed: 11/13/2022] Open
Abstract
The insulin-like growth factor (IGF) axis is required for the differentiation, development, and maintenance of bone tissue. Accordingly, dysregulation of this axis is associated with various skeletal pathologies including growth abnormalities and compromised bone structure. It is becoming increasingly apparent that the action of the IGF axis must be viewed holistically taking into account not just the actions of the growth factors and receptors, but also the influence of soluble high affinity IGF binding proteins (IGFBPs).There is a recognition that IGFBPs exert IGF-dependent and IGF-independent effects in bone and other tissues and that an understanding of the mechanisms of action of IGFBPs and their regulation in the pericellular environment impact critically on tissue physiology. In this respect, a group of IGFBP proteinases (which may be considered as ancillary members of the IGF axis) play a crucial role in regulating IGFBP function. In this model, cleavage of IGFBPs by specific proteinases into fragments with lower affinity for growth factor(s) regulates the partition of IGFs between IGFBPs and cell surface IGF receptors. In this review, we examine the importance of IGFBP function in bone tissue with special emphasis on the role of pregnancy associated plasma protein-A (PAPP-A). We examine the function of PAPP-A primarily as an IGFBP-4 proteinase and present evidence that PAPP-A induced cleavage of IGFBP-4 is potentially a key regulatory step in bone metabolism. We also highlight some recent findings with regard to IGFBP-2 and IGFBP-5 (also PAPP-A substrates) function in bone tissue and briefly discuss the actions of the other three IGFBPs (-1, -3, and -6) in this tissue. Although our main focus will be in bone we will allude to IGFBP activity in other cells and tissues where appropriate.
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Affiliation(s)
- James Beattie
- Division of Oral Biology, Leeds School of Dentistry, Level 7 Wellcome Trust Brenner Building, University of Leeds, St James University Hospital, Leeds, United Kingdom
- *Correspondence: James Beattie,
| | - Hasanain Al-Khafaji
- Division of Oral Biology, Leeds School of Dentistry, Level 7 Wellcome Trust Brenner Building, University of Leeds, St James University Hospital, Leeds, United Kingdom
| | - Pernille R. Noer
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Hanaa Esa Alkharobi
- Department of Oral Biology, Dental College, King AbdulAziz University, Jeddah, Saudi Arabia
| | - Aishah Alhodhodi
- Division of Oral Biology, Leeds School of Dentistry, Level 7 Wellcome Trust Brenner Building, University of Leeds, St James University Hospital, Leeds, United Kingdom
| | - Josephine Meade
- Division of Oral Biology, Leeds School of Dentistry, Level 7 Wellcome Trust Brenner Building, University of Leeds, St James University Hospital, Leeds, United Kingdom
| | - Reem El-Gendy
- Division of Oral Biology, Leeds School of Dentistry, Level 7 Wellcome Trust Brenner Building, University of Leeds, St James University Hospital, Leeds, United Kingdom
- Department of Oral Pathology, Faculty of Dentistry, Suez Canal University, Ismailia, Egypt
| | - Claus Oxvig
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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Chen L, Xiang B, Wang X, Xiang C. Exosomes derived from human menstrual blood-derived stem cells alleviate fulminant hepatic failure. Stem Cell Res Ther 2017; 8:9. [PMID: 28115012 PMCID: PMC5260032 DOI: 10.1186/s13287-016-0453-6] [Citation(s) in RCA: 142] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 11/28/2016] [Accepted: 12/07/2016] [Indexed: 02/08/2023] Open
Abstract
Background Human menstrual blood-derived stem cells (MenSCs) are a novel source of MSCs that provide the advantage of being easy to collect and isolate. Exosomes contain some mRNAs and adhesion molecules that can potentially impact cellular and animal physiology. This study aimed to investigate the therapeutic potential of MenSC-derived exosomes (MenSC-Ex) on AML12 cells (in vitro) and D-GalN/LPS-induced FHF mice (in vivo). Methods Transmission electron microscopy and Western blot were used to identify MenSC-Ex. Antibody array was used to examine cytokine levels on MenSC-Ex. MenSC-Ex were treated in D-GalN/LPS-induced AML12 in vitro. Cell proliferation and apoptosis were measured. MenSC-Ex were injected into the tail veins of mice 24 h before treatment with D-GalN/LPS. Blood and liver tissues served as physiological and biochemical indexes. The number of liver mononuclear cells (MNCs) and the amount of the active apoptotic protein caspase-3 were determined to elaborate the mechanism of hepatoprotective activity. Results Human menstrual blood-derived stem cell-derived exosomes (MenSC-Ex) are bi-lipid membrane vesicles that have a round, ball-like shape with a diameter of approximately 30–100 nm. Cytokine arrays have shown that MenSC-Ex expressed cytokines, including ICAM-1, angiopoietin-2, Axl, angiogenin, IGFBP-6, osteoprotegerin, IL-6, and IL-8. MenSC-Ex markedly improved liver function, enhanced survival rates, and inhibited liver cell apoptosis at 6 h after transplantation. MenSC-Ex migrated to sites of injury and to AML12 cells (a mouse hepatocyte cell line), respectively. Moreover, MenSC-Ex reduced the number of liver mononuclear cells (MNCs) and the amount of the active apoptotic protein caspase-3 in injured livers. Conclusions In conclusion, our results provide preliminary evidence for the anti-apoptotic capacity of MenSC-Ex in FHF and suggest that MenSC-Ex may be an alternative therapeutic approach to treat FHF. Electronic supplementary material The online version of this article (doi:10.1186/s13287-016-0453-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lu Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Bingyu Xiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Xiaojun Wang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Charlie Xiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Zhejiang University, Hangzhou, 310003, China.
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10
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Bach LA. Current ideas on the biology of IGFBP-6: More than an IGF-II inhibitor? Growth Horm IGF Res 2016; 30-31:81-86. [PMID: 27681092 DOI: 10.1016/j.ghir.2016.09.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 09/15/2016] [Accepted: 09/22/2016] [Indexed: 12/22/2022]
Abstract
IGFBP-6 binds IGF-II with higher affinity than IGF-I and it is a relatively specific inhibitor of IGF-II actions. More recently, IGFBP-6 has also been reported to have IGF-independent effects on cell proliferation, survival, differentiation and migration. IGFBP-6 binds to several ligands in the extracellular space, cytoplasm and nucleus. These interactions, together with activation of distinct intracellular signaling pathways, may contribute to its IGF-independent actions; for example, IGF-independent migration induced by IGFBP-6 involves interaction with prohibitin-2 and activation of MAP kinase pathways. A major challenge for the future is delineating the relative roles of the IGF-dependent and -independent actions of IGFBP-6, which may lead to the development of therapeutic approaches for diseases including cancer.
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Affiliation(s)
- Leon A Bach
- Department of Medicine (Alfred), Monash University, Prahran 3181, Australia; Department of Endocrinology and Diabetes, Alfred Hospital, Melbourne 3004, Australia.
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11
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Abstract
The skeleton is an exquisitely sensitive and archetypal T3-target tissue that demonstrates the critical role for thyroid hormones during development, linear growth, and adult bone turnover and maintenance. Thyrotoxicosis is an established cause of secondary osteoporosis, and abnormal thyroid hormone signaling has recently been identified as a novel risk factor for osteoarthritis. Skeletal phenotypes in genetically modified mice have faithfully reproduced genetic disorders in humans, revealing the complex physiological relationship between centrally regulated thyroid status and the peripheral actions of thyroid hormones. Studies in mutant mice also established the paradigm that T3 exerts anabolic actions during growth and catabolic effects on adult bone. Thus, the skeleton represents an ideal physiological system in which to characterize thyroid hormone transport, metabolism, and action during development and adulthood and in response to injury. Future analysis of T3 action in individual skeletal cell lineages will provide new insights into cell-specific molecular mechanisms and may ultimately identify novel therapeutic targets for chronic degenerative diseases such as osteoporosis and osteoarthritis. This review provides a comprehensive analysis of the current state of the art.
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Affiliation(s)
- J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, United Kingdom
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, United Kingdom
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12
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Milanesi A, Lee JW, Kim NH, Liu YY, Yang A, Sedrakyan S, Kahng A, Cervantes V, Tripuraneni N, Cheng SY, Perin L, Brent GA. Thyroid Hormone Receptor α Plays an Essential Role in Male Skeletal Muscle Myoblast Proliferation, Differentiation, and Response to Injury. Endocrinology 2016; 157:4-15. [PMID: 26451739 PMCID: PMC4701883 DOI: 10.1210/en.2015-1443] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Thyroid hormone plays an essential role in myogenesis, the process required for skeletal muscle development and repair, although the mechanisms have not been established. Skeletal muscle develops from the fusion of precursor myoblasts into myofibers. We have used the C2C12 skeletal muscle myoblast cell line, primary myoblasts, and mouse models of resistance to thyroid hormone (RTH) α and β, to determine the role of thyroid hormone in the regulation of myoblast differentiation. T3, which activates thyroid hormone receptor (TR) α and β, increased myoblast differentiation whereas GC1, a selective TRβ agonist, was minimally effective. Genetic approaches confirmed that TRα plays an important role in normal myoblast proliferation and differentiation and acts through the Wnt/β-catenin signaling pathway. Myoblasts with TRα knockdown, or derived from RTH-TRα PV (a frame-shift mutation) mice, displayed reduced proliferation and myogenic differentiation. Moreover, skeletal muscle from the TRα1PV mutant mouse had impaired in vivo regeneration after injury. RTH-TRβ PV mutant mouse model skeletal muscle and derived primary myoblasts did not have altered proliferation, myogenic differentiation, or response to injury when compared with control. In conclusion, TRα plays an essential role in myoblast homeostasis and provides a potential therapeutic target to enhance skeletal muscle regeneration.
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Affiliation(s)
- Anna Milanesi
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Jang-Won Lee
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Nam-Ho Kim
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Yan-Yun Liu
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - An Yang
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Sargis Sedrakyan
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Andrew Kahng
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Vanessa Cervantes
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Nikita Tripuraneni
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Sheue-yann Cheng
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Laura Perin
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
| | - Gregory A Brent
- Department of Medicine (A.M., Y.-Y.L., A.Y., G.A.B.), Veterans Affairs Greater Los Angeles Healthcare System, and Departments of Medicine and Physiology, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California 90073; Department of Neurosurgery (J.-W.L., N.-H.K., A.K., V.C.), Cedars-Sinai Medical Center, Los Angeles, California 90048; Department of Urology (S.S., N.T., L.P.), Children's Hospital Los Angeles, University of Southern California, Los Angeles, California 90027; and National Cancer Institute (S.C.), Bethesda, Maryland 20892
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13
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Menni C, Kiddle SJ, Mangino M, Viñuela A, Psatha M, Steves C, Sattlecker M, Buil A, Newhouse S, Nelson S, Williams S, Voyle N, Soininen H, Kloszewska I, Mecocci P, Tsolaki M, Vellas B, Lovestone S, Spector TD, Dobson R, Valdes AM. Circulating Proteomic Signatures of Chronological Age. J Gerontol A Biol Sci Med Sci 2015; 70:809-16. [PMID: 25123647 PMCID: PMC4469006 DOI: 10.1093/gerona/glu121] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 06/24/2014] [Indexed: 11/17/2022] Open
Abstract
To elucidate the proteomic features of aging in plasma, the subproteome targeted by the SOMAscan assay was profiled in blood samples from 202 females from the TwinsUK cohort. Findings were replicated in 677 independent individuals from the AddNeuroMed, Alzheimer's Research UK, and Dementia Case Registry cohorts. Results were further validated using RNAseq data from whole blood in TwinsUK and the most significant proteins were tested for association with aging-related phenotypes after adjustment for age. Eleven proteins were associated with chronological age and were replicated at protein level in an independent population. These were further investigated at gene expression level in 384 females from the TwinsUK cohort. The two most strongly associated proteins were chordin-like protein 1 (meta-analysis β [SE] = 0.013 [0.001], p = 3.66 × 10(-46)) and pleiotrophin (0.012 [0.005], p = 3.88 × 10(-41)). Chordin-like protein 1 was also significantly correlated with birthweight (0.06 [0.02], p = 0.005) and with the individual Framingham 10-years cardiovascular risk scores in TwinsUK (0.71 [0.18], p = 9.9 × 10(-5)). Pleiotrophin is a secreted growth factor with a plethora of functions in multiple tissues and known to be a marker for cardiovascular risk and osteoporosis. Our study highlights the importance of proteomics to identify some molecular mechanisms involved in human health and aging.
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Affiliation(s)
- Cristina Menni
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Steven J Kiddle
- Institute of Psychiatry, King's College London. Medical Research Council Social, Genetic and Developmental Psychiatry Centre, King's College London
| | - Massimo Mangino
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Ana Viñuela
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Maria Psatha
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Claire Steves
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Martina Sattlecker
- Institute of Psychiatry, King's College London. National Institute for Health Research Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London
| | - Alfonso Buil
- Department of Genetic Medicine and Development, University of Geneva Medical School, Switzerland
| | - Stephen Newhouse
- Institute of Psychiatry, King's College London. National Institute for Health Research Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London
| | | | | | - Nicola Voyle
- Institute of Psychiatry, King's College London. Medical Research Council Social, Genetic and Developmental Psychiatry Centre, King's College London
| | - Hilkka Soininen
- Department of Neurology, University of Eastern Finland and Kuopio University Hospital, Finland
| | | | - Patrizia Mecocci
- Institute of Gerontology and Geriatrics, University of Perugia, Italy
| | - Magda Tsolaki
- Department of Neurology III, Aristotle University, Thessaloniki, Greece
| | - Bruno Vellas
- Institut national de la sante et de la recherche medicale University of Toulouse, France
| | | | - Tim D Spector
- Department of Twin Research and Genetic Epidemiology, King's College London
| | - Richard Dobson
- Institute of Psychiatry, King's College London. National Institute for Health Research Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London
| | - Ana M Valdes
- Department of Twin Research and Genetic Epidemiology, King's College London. Academic Rheumatology, University of Nottingham
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14
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Bach LA. Recent insights into the actions of IGFBP-6. J Cell Commun Signal 2015; 9:189-200. [PMID: 25808083 DOI: 10.1007/s12079-015-0288-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 03/16/2015] [Indexed: 12/28/2022] Open
Abstract
IGFBP-6 is an O-linked glycoprotein that preferentially binds IGF-II over IGF-I. It is a relatively selective inhibitor of IGF-II actions including proliferation, survival and differentiation of a wide range of cells. IGFBP-6 has recently been shown to have a number of IGF-independent actions, including promotion of apoptosis in some cells and inhibition of angiogenesis. IGFBP-6 also induces migration of tumour cells including rhabdomyosarcomas by an IGF-independent mechanism. This chemotactic effect is mediated by MAP kinases. IGFBP-6 binds to prohibitin-2 on the cell surface and the latter is required for IGFBP-6-induced migration by a mechanism that is independent of MAP kinases. IGFBP-6 may enter the nucleus and modulate cell survival and differentiation. IGFBP-6 expression is decreased in a number of cancer cells and it has been postulated to act as a tumour suppressor. IGFBP-6 expression is increased in a smaller number of cancers, which may reflect a compensatory mechanism to control IGF-II actions or IGF-independent actions. The relative balance of IGF-dependent and IGF-independent actions of IGFBP-6 in vivo together with the related question regarding the roles of IGFBP-6 binding to IGF and non-IGF ligands are keys to understanding the physiological role of this protein.
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Affiliation(s)
- Leon A Bach
- Department of Medicine (Alfred), Monash University, Prahran, 3181, Australia,
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15
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Abstract
The six members of the family of insulin-like growth factor (IGF) binding proteins (IGFBPs) were originally characterized as passive reservoirs of circulating IGFs, but they are now understood to have many actions beyond their endocrine role in IGF transport. IGFBPs also function in the pericellular and intracellular compartments to regulate cell growth and survival - they interact with many proteins, in addition to their canonical ligands IGF-I and IGF-II. Intranuclear roles of IGFBPs in transcriptional regulation, induction of apoptosis and DNA damage repair point to their intimate involvement in tumour development, progression and resistance to treatment. Tissue or circulating IGFBPs might also be useful as prognostic biomarkers.
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Affiliation(s)
- Robert C Baxter
- Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales 2065, Australia
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16
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Zhao HM, Sheng MJ, Yu J. Expression of IGFBP-6 in a proliferative vitreoretinopathy rat model and its effects on retinal pigment epithelial cell proliferation and migration. Int J Ophthalmol 2014; 7:27-33. [PMID: 24634859 DOI: 10.3980/j.issn.2222-3959.2014.01.05] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 09/27/2013] [Indexed: 12/17/2022] Open
Abstract
AIM To investigate the expression of insulin-like growth factor binding protein-6 (IGFBP-6) in a proliferative vitreoretinopathy (PVR) model and its effects on proliferation and migration in retinal pigment epithelial (RPE) cells. METHODS A PVR Wistar rat model was established by the intravitreal injection of RPE-J cells combined with platelet-rich plasma (PRP). The expression levels of IGFBP-6 were tested by ELISA. ARPE-19 cell proliferation was evaluated by the MTS method, and cell migration was evaluated by wound healing assays. RESULTS The success rate of the PVR model was 89.3% (25/28). IGFBP-6 was expressed at higher levels in the vitreous, serum and retina of rats experiencing advanced PVR (grade 3) than in the control group (vitreous: 152.80±15.08ng/mL vs 105.44±24.81ng/mL, P>0.05; serum: 93.48±9.27ng/mL vs 80.59±5.20ng/mL, P<0.05; retina: 3.02±0.38ng/mg vs 2.05±0.53ng/mg, P<0.05). In vitro, IGFBP-6 (500ng/mL) inhibited the IGF-II (50ng/mL) induced ARPE-19 cell proliferation (OD value at 24h: from 1.38±0.05 to 1.30±0.02; 48h: from 1.44±0.06 to 1.35±0.05). However, it did not affect basal or VEGF-, TGF-β- and PDGF-induced cell proliferation. IGFBP-6 (500ng/mL) reduced the IGF-II (50ng/mL)-induced would healing rate [24h: from (43.91±3.85)% to (29.76±2.49)%; 48 h: from (66.09±1.67)% to (59.88±3.43)%]. CONCLUSION Concentrations of IGFBP-6 increased in the vitreous, serum, and retinas only in advanced PVR in vivo. IGFBP-6 also inhibited IGF-II-induced cell proliferation in a not dose or time dependent manner and migration. IGFBP-6 participates in the development of PVR and might play a protective role in PVR.
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Affiliation(s)
- Hong-Mei Zhao
- Department of Ophthalmology, the Tenth People's Hospital of Tongji University, Shanghai 200072, China
| | - Min-Jie Sheng
- Department of Ophthalmology, the Tenth People's Hospital of Tongji University, Shanghai 200072, China
| | - Jing Yu
- Department of Ophthalmology, the Tenth People's Hospital of Tongji University, Shanghai 200072, China
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17
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Vieira FA, Thorne MAS, Stueber K, Darias M, Reinhardt R, Clark MS, Gisbert E, Power DM. Comparative analysis of a teleost skeleton transcriptome provides insight into its regulation. Gen Comp Endocrinol 2013; 191:45-58. [PMID: 23770218 DOI: 10.1016/j.ygcen.2013.05.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 05/24/2013] [Accepted: 05/29/2013] [Indexed: 12/16/2022]
Abstract
An articulated endoskeleton that is calcified is a unifying innovation of the vertebrates, however the molecular basis of the structural divergence between terrestrial and aquatic vertebrates, such as teleost fish, has not been determined. In the present study long-read next generation sequencing (NGS, Roche 454 platform) was used to characterize acellular perichondral bone (vertebrae) and chondroid bone (gill arch) in the gilthead sea bream (Sparus auratus). A total of 15.97 and 14.53Mb were produced, respectively from vertebrae and gill arch cDNA libraries and yielded 32,374 and 28,371 contigs (consensus sequences) respectively. 10,455 contigs from vertebrae and 10,625 contigs from gill arches were annotated with gene ontology terms. Comparative analysis of the global transcriptome revealed 4249 unique transcripts in vertebrae, 4201 unique transcripts in the gill arches and 3700 common transcripts. Several core gene networks were conserved between the gilthead sea bream and mammalian skeleton. Transcripts for putative endocrine factors were identified in acellular gilthead sea bream bone suggesting that in common with mammalian bone it can act as an endocrine tissue. The acellular bone of the vertebra, in contrast to current opinion based on histological analysis, was responsive to a short fast and significant (p<0.05) down-regulation of several transcripts identified by NGS, osteonectin, osteocalcin, cathepsin K and IGFI occurred. In gill arches fasting caused a significant (p<0.05) down-regulation of osteocalcin and up-regulation of MMP9.
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18
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Abstract
The IGF (insulin-like growth factor) system is essential for physiological growth and it is also implicated in a number of diseases including cancer. IGF activity is modulated by a family of high-affinity IGF-binding proteins, and IGFBP-6 is distinctive because of its marked binding preference for IGF-II over IGF-I. A principal role for IGFBP-6 is inhibition of IGF-II actions, but recent studies have indicated that IGFBP-6 also has IGF-independent effects, including inhibition of angiogenesis and promotion of cancer cell migration. The present review briefly summarizes the IGF system in physiology and disease before focusing on recent studies on the regulation and actions of IGFBP-6, and its potential roles in cancer cells. Given the widespread interest in IGF inhibition in cancer therapeutics, increasing our understanding of the mechanisms underlying the actions of the IGF ligands, receptors and binding proteins, including IGFBP-6, will enhance our ability to develop optimal treatments that can be targeted to the most appropriate patients.
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