1
|
Durham EL, Grey ZJ, Black L, Howie RN, Barth JL, Lee BS, Cray JJ. Sfrp4 expression in thyroxine treated calvarial cells. Life Sci 2022; 311:121158. [PMID: 36370870 PMCID: PMC9719041 DOI: 10.1016/j.lfs.2022.121158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/24/2022] [Accepted: 11/04/2022] [Indexed: 11/11/2022]
Abstract
AIMS Evidence suggests alterations of thyroid hormone levels can disrupt normal bone development. Most data suggest the major targets of thyroid hormones to be the Htra1/Igf1 pathway. Recent discovery by our group suggests involvement of targets WNT pathway, specifically overexpression of antagonist Sfrp4 in the presence of exogenous thyroid hormone. MAIN METHODS Here we aimed to model these interactions in vitro using primary and isotype cell lines to determine if thyroid hormone drives increased Sfrp4 expression in cells relevant to craniofacial development. Transcriptional profiling, bioinformatics interrogation, protein and function analyses were used. KEY FINDINGS Affymetrix transcriptional profiling found Sfrp4 overexpression in primary cranial suture derived cells stimulated with thyroxine in vitro. Interrogation of the SFRP4 promoter identified multiple putative binding sites for thyroid hormone receptors. Experimentation with several cell lines demonstrated that thyroxine treatment induced Sfrp4 expression, demonstrating that Sfrp4 mRNA and protein levels are not tightly coupled. Transcriptional and protein analyses demonstrate thyroid hormone receptor binding to the proximal promoter of the target gene Sfrp4 in murine calvarial pre-osteoblasts. Functional analysis after thyroxine hormone stimulation for alkaline phosphatase activity shows that pre-osteoblasts increase alkaline phosphatase activity compared to other cell types, suggesting cell type susceptibility. Finally, we added recombinant SFRP4 to pre-osteoblasts in combination with thyroxine treatment and observed a significant decrease in alkaline phosphatase positivity. SIGNIFICANCE Taken together, these results suggest SFRP4 may be a key regulatory molecule that prevents thyroxine driven osteogenesis. These data corroborate clinical findings indicating a potential for SFRP4 as a diagnostic or therapeutic target for hyperostotic craniofacial disorders.
Collapse
Affiliation(s)
- Emily L Durham
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Pediatrics, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Zachary J Grey
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Laurel Black
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - R Nicole Howie
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Jeremy L Barth
- Department of Regenerative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Beth S Lee
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - James J Cray
- Department of Biomedical Education and Anatomy, College of Medicine, The Ohio State University, Columbus, OH, USA; Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA.
| |
Collapse
|
2
|
Xian W, Wu D, Liu B, Hong S, Huo Z, Xiao H, Li Y. Graves' disease and inflammatory bowel disease: A bidirectional Mendelian randomization. J Clin Endocrinol Metab 2022; 108:1075-1083. [PMID: 36459455 PMCID: PMC10099169 DOI: 10.1210/clinem/dgac683] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/17/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022]
Abstract
CONTEXT Both Graves' disease (GD) and inflammatory bowel disease (IBD) are common autoimmune diseases that severely damage patients' quality of life. Previous epidemiological studies have suggested associations between GD and IBD. However, whether a causal relationship exists between these two diseases remains unknown. OBJECTIVE To infer a causal relationship between GD and IBD using bidirectional two-sample Mendelian randomization(MR). METHODS We performed bidirectional two-sample MR to infer a causal relationship between GD and IBD using GWAS summary data obtained from Biobank Japan (BBJ) and the International Inflammatory Bowel Disease Genetic Consortium (IIBDGC). Several methods (random-effect inverse variance weighted, weighted median, MR‒Egger regression, and MR-PRESSO) were used to ensure the robustness of the causal effect. Heterogeneity was measured based on Cochran's Q value. Horizontal pleiotropy was evaluated by MR‒Egger regression and leave-one-out analysis. RESULTS Genetically predicted IBD may increase the risk of GD by 24% (OR 1.24, 95% CI 1.01-1.52, p = 0.041). Crohn's disease (CD) may increase the risk of GD, whereas ulcerative colitis (UC) may prevent patients from developing GD. Conversely, genetically predicted GD may slightly increase the risk of CD, although evidence indicating that the presence of GD increased the risk of UC or IBD was lacking. Outlier-corrected results were consistent with raw causal estimates. CONCLUSIONS Our study revealed a potentially higher comorbidity rate for GD and CD. However, UC might represent a protective factor for GD. The underlying mechanism and potential common pathways await discovery.
Collapse
Affiliation(s)
- Wei Xian
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Dide Wu
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Boyuan Liu
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Shubin Hong
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Zijun Huo
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Haipeng Xiao
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Yanbing Li
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| |
Collapse
|
3
|
Abstract
We report a case of a woman in her 50s with chronic teprotumumab-associated sensorineural hearing loss. The patient presented with chronic thyroid eye disease with proptosis and diplopia despite systemic thyroid control and orbital decompression. She was started on teprotumumab but developed tinnitus after the third dose, followed by frank hearing loss after the fifth dose. Her audiogram showed bilateral mild to moderate-severe hearing loss, which was significantly worse compared with her baseline audiogram obtained prior to treatment. Teprotumumab was immediately stopped, however repeat audiogram 6 weeks later showed no improvement. Given potentially irreversible sensorineural hearing loss, we recommend close monitoring with regular audiometric testing before, during and after teprotumumab therapy and propose potential treatment to reverse its effects in the ear.
Collapse
Affiliation(s)
- Audrey Chow
- Ophthalmology, California Pacific Medical Center, San Francisco, California, USA
| | - Rona Z Silkiss
- Ophthalmic Plastic, Reconstructive and Orbital Surgery, California Pacific Medical Center, San Francisco, California, USA.,Silkiss Eye Surgery, Oakland, California, USA
| |
Collapse
|
4
|
Shimatsu A, Nakamura A, Takahashi Y, Fujio S, Satoh F, Tahara S, Nishioka H, Takano K, Yamashita M, Arima H, Tominaga A, Tateishi S, Matsushita Y. Preoperative and long-term efficacy and safety of lanreotide autogel in patients with thyrotropin-secreting pituitary adenoma: a multicenter, single-arm, phase 3 study in Japan. Endocr J 2021; 68:791-805. [PMID: 33692246 DOI: 10.1507/endocrj.ej20-0707] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Somatostatin analogs are recommended for pharmacotherapy of TSH-secreting pituitary adenoma (TSHoma). A multicenter clinical trial was conducted to evaluate the efficacy and safety of lanreotide autogel treatment for TSHoma. A total of 13 Japanese patients with TSHoma were enrolled from February to December 2018 and treated with lanreotide autogel 90 mg every 4 weeks, with dose adjustments to 60 mg or 120 mg. Analysis was performed on data from patients receiving preoperative treatment (n = 6) up to 24 weeks and from those receiving primary or postoperative treatment (n = 7) up to 52 weeks. The primary efficacy endpoints were serum concentrations of TSH, free triiodothyronine (FT3), and free thyroxine (FT4). The secondary efficacy endpoints were pituitary tumor size and clinical symptoms. The serum concentrations of TSH, FT3, and FT4 decreased with treatment, and euthyroid status was maintained until final assessment. FT4 at final assessment was within reference ranges in 10/13 patients. The median (interquartile range) percent change in pituitary tumor size from baseline at final assessment was -23.8% (-38.1, -19.8). The clinical symptoms were also improved. The patients receiving preoperative treatment did not develop perioperative thyroid storm. Regarding safety, adverse events were observed in 12/13 patients, but none discontinued treatment. The common adverse events were gastrointestinal disorders (12/13 patients) and administration site reactions (5/13 patients). Lanreotide autogel may be effective for controlling thyroid function and reducing the pituitary tumor size, and is tolerable in patients with TSHoma (Japic Clinical Trials Information; JapicCTI-173772).
Collapse
Affiliation(s)
- Akira Shimatsu
- Clinical Research Institute, National Hospital Organization Kyoto Medical Center, Kyoto 612-8555, Japan
- Advanced Medical Care Center, Kusatsu General Hospital, Kusatsu 525-8585, Japan
| | - Akinobu Nakamura
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo 060-8638, Japan
| | - Yutaka Takahashi
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
- Department of Diabetes and Endocrinology, Nara Medical University, Kashihara 634-8522, Japan
| | - Shingo Fujio
- Department of Neurosurgery, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8520, Japan
| | - Fumitoshi Satoh
- Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Hospital, Sendai 980-8577, Japan
| | - Shigeyuki Tahara
- Department of Neurological Surgery, Nippon Medical School, Tokyo 113-8603, Japan
| | - Hiroshi Nishioka
- Department of Hypothalamic and Pituitary Surgery, Toranomon Hospital, Tokyo 105-8470, Japan
| | - Koji Takano
- Department of Endocrinology, Diabetes & Metabolism, Kitasato University School of Medicine, Sagamihara 252-0374, Japan
| | - Miho Yamashita
- Second Division, Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
- International Center, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
| | - Hiroshi Arima
- Department of Endocrinology and Diabetes, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Atsushi Tominaga
- Department of Neurosurgery, Hiroshima Prefectural Hospital, Hiroshima 734-8530, Japan
| | | | | |
Collapse
|
5
|
Abstract
Several endocrine systems have important effects on bone tissue. Thyroid hormones are essential for normal growth and development. Excess of these hormones will result in clinically significant changes that may require intervention. Glucocorticoids also have a marked effect on bone metabolism by several pathways. Their endogenous or exogenous excess will induce pathological processes that might elevate the risk of fractures. Insulin and the carbohydrate metabolism elicit a physiological effect on bone; however, the lack of insulin (type 1 diabetes) or insulin resistance (type 2 diabetes) have deleterious influence on bone tissue.
Collapse
Affiliation(s)
- Peter Lakatos
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary.
| | - Balazs Szili
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Bence Bakos
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Istvan Takacs
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Zsuzsanna Putz
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary
| | - Ildiko Istenes
- 1st Department of Medicine, Semmelweis University, Budapest, Hungary
| |
Collapse
|
6
|
Tseng FY, Chen YT, Chi YC, Chen PL, Yang WS. Serum levels of insulin-like growth factor 1 are negatively associated with log transformation of thyroid-stimulating hormone in Graves' disease patients with hyperthyroidism or subjects with euthyroidism: A prospective observational study. Medicine (Baltimore) 2019; 98:e14862. [PMID: 30882687 PMCID: PMC6426554 DOI: 10.1097/md.0000000000014862] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Insulin-like growth factor 1 (IGF-1) has a molecular structure similar to that of insulin. As an essential mediator of growth hormone, IGF-1 plays a vital role in growth of children and anabolic effects of adults. We evaluated the serum levels of IGF-1 in patients with hyperthyroidism or euthyroidism.In this study, 30 patients each of Graves' disease with hyperthyroidism (HY group) and euthyroid individuals (EU group) were recruited. The HY patients were treated with antithyroid regimens as clinically indicated. No medications were given to EU patients. The demographic characteristics and anthropometric and laboratory data of both groups at baseline and 6 months were compared. Associations between levels of IGF-1 and free thyroxine (fT4), thyroid-stimulating hormone (TSH), or log transformation of TSH (logTSH) were analyzed.At baseline, the HY patients had significantly higher serum IGF-1 levels than EU patients (median [Q1, Q3]: 305.4 [257.4, 368.1] vs. 236.7 [184.6, 318.8] ng/mL, P = .007). At 6 months, the HY patients still had higher serum levels of IGF-1 than EU patients (299.5 [249.9, 397.9] vs 222.1 [190.2, 305.4] ng/mL, P = .003). At baseline, the serum levels of IGF-1 in the HY and EU patients were positively associated with fT4 (β = 29.02, P = .002) and negatively associated with TSH (β = -31.46, P = .042) and logTSH (β = -29.04, P = .007). The associations between serum levels of IGF-1 with fT4 or TSH became insignificant at 6 months. However, the serum IGF-1 levels had persistent negative associations with logTSH at 6 months (β = -26.65, P = .021). The negative associations between IGF-1 and logTSH at baseline and 6 months remained significant even after adjustment with sex and age (β = -20.22, P = .023 and β = -20.51, P = .024, respectively).The HY patients had higher serum IGF-1 levels than EU patients. The serum IGF-1 concentrations were negatively associated with logTSH in patients with hyperthyroidism or euthyroidism.
Collapse
Affiliation(s)
- Fen-Yu Tseng
- Department of Internal Medicine, National Taiwan University Hospital
| | - Yen-Ting Chen
- Graduate Institute of Clinical Medicine, College of Medicine
| | - Yu-Chiao Chi
- Graduate Institute of Clinical Medicine, College of Medicine
| | - Pei-Lung Chen
- Department of Internal Medicine, National Taiwan University Hospital
- Department of Medical Genetics, National Taiwan University Hospital
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wei-Shiung Yang
- Department of Internal Medicine, National Taiwan University Hospital
- Graduate Institute of Clinical Medicine, College of Medicine
| |
Collapse
|
7
|
Witkowska-Sędek E, Borowiec A, Majcher A, Sobol M, Rumińska M, Pyrżak B. Thyroid function in children with growth hormone deficiency during long-term growth hormone replacement therapy. Cent Eur J Immunol 2018; 43:255-61. [PMID: 30588169 DOI: 10.5114/ceji.2018.80043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/04/2018] [Indexed: 11/17/2022] Open
Abstract
Aim of the study The aim of this study was to investigate the effects of growth hormone (GH) therapy on thyroid function in a group of euthyroid children with isolated idiopathic growth hormone deficiency (GHD). Material and methods The study was retrospective and included 117 children treated with GH for 1-4 years. Anthropometric measurements and serum concentrations of insulin-like growth factor-1 (IGF-1), thyroid-stimulating hormone (TSH), and free thyroxine (fT4) were analysed at baseline and during GH therapy. Results TSH levels did not change significantly after the initiation of GH treatment, while fT4 levels decreased after the second year of GH treatment (p < 0.01) and remained lower than baseline until the end of observation (p < 0.01, after both the third and fourth year of therapy) in the whole group. Analysis according to baseline pubertal status revealed significant changes in TSH and fT4 levels during GH treatment, but only in the prepubertal children. Multiple regression analysis confirmed that mean GH doses administered in the first two years of GH therapy were independently (R = 0.218, p < 0.05) associated with changes in fT4 levels in this period (∆fT42 years – baseline), even when taking into account changes in height SDS and bone age. Conclusions FT4 levels decreased during GH replacement therapy, while TSH levels appeared to be unaffected by GH therapy. Prepubertal children seem to be more predisposed to thyroid function alterations during such therapy in comparison to pubertal children. Changes in fT4 levels during GH replacement therapy are related to GH doses.
Collapse
|
8
|
Martins GM, Teixeira MBCG, Silva MV, Neofiti-Papi B, Miranda-Rodrigues M, Brum PC, Gouveia CHA. Global Disruption of α2A Adrenoceptor Barely Affects Bone Tissue but Minimizes the Detrimental Effects of Thyrotoxicosis on Cortical Bone. Front Endocrinol (Lausanne) 2018; 9:486. [PMID: 30233491 PMCID: PMC6127616 DOI: 10.3389/fendo.2018.00486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 08/06/2018] [Indexed: 01/02/2023] Open
Abstract
Evidence shows that sympathetic nervous system (SNS) activation inhibits bone formation and activates bone resorption leading to bone loss. Because thyroid hormone (TH) interacts with the SNS to control several physiological processes, we raised the hypothesis that this interaction also controls bone remodeling. We have previously shown that mice with double-gene inactivation of α2A- and -adrenoceptors (α2A/2C-AR-/-) present high bone mass (HBM) phenotype and resistance to thyrotoxicosis-induced osteopenia, which supports a TH-SNS interaction to control bone mass and suggests that it involves α2-AR signaling. Accordingly, we detected expression of α2A-AR, α2B-AR and α2C-AR in the skeleton, and that triiodothyronine (T3) modulates α2C-AR mRNA expression in the bone. Later, we found that mice with single-gene inactivation of α2C-AR (α2C-AR-/-) present low bone mass in the femur and HBM in the vertebra, but that both skeletal sites are resistant to TH-induce osteopenia, showing that the SNS actions occur in a skeletal site-dependent manner, and that thyrotoxicosis depends on α2C-AR signaling to promote bone loss. To further dissect the specific roles of α2-AR subtypes, in this study, we evaluated the skeletal phenotype of mice with single-gene inactivation of α2A-AR (α2A-AR-/-), and the effect of daily treatment with a supraphysiological dose of T3, for 4 or 12 weeks, on bone microarchitecture and bone resistance to fracture. Micro-computed tomographic (μCT) analysis revealed normal trabecular and cortical bone structure in the femur and vertebra of euthyroid α2A-AR-/- mice. Thyrotoxicosis was more detrimental to femoral trabecular bone in α2A-AR-/- than in WT mice, whereas this bone compartment had been previously shown to present resistance to thyrotoxicosis in α2C-AR-/- mice. Altogether these findings reveal that TH excess depends on α2C-AR signaling to negatively affect femoral trabecular bone. In contrast, thyrotoxicosis was more deleterious to femoral and vertebral cortical bone in WT than in α2A-AR-/- mice, suggesting that α2A-AR signaling contributes to TH actions on cortical bone. These findings further support a TH-SNS interaction to control bone physiology, and suggest that α2A-AR and α2C-AR signaling pathways have key roles in the mechanisms through which thyrotoxicosis promotes its detrimental effects on bone remodeling, structure and resistance to fracture.
Collapse
Affiliation(s)
- Gisele M. Martins
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Department of Morphology, Federal University of Espírito Santo, Vitória, Brazil
| | | | - Marcos V. Silva
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Department of Morphology, Federal University of Sergipe, Aracaju, Brazil
| | - Bianca Neofiti-Papi
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- School of Medicine, University of São Paulo, São Paulo, Brazil
| | - Manuela Miranda-Rodrigues
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- University of Western Ontario, London, ON, Canada
| | - Patricia C. Brum
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Cecilia H. A. Gouveia
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- School of Medicine, University of São Paulo, São Paulo, Brazil
- *Correspondence: Cecilia H. A. Gouveia
| |
Collapse
|
9
|
Papageorgiou M, Elliott-Sale KJ, Parsons A, Tang JCY, Greeves JP, Fraser WD, Sale C. Effects of reduced energy availability on bone metabolism in women and men. Bone 2017; 105:191-199. [PMID: 28847532 DOI: 10.1016/j.bone.2017.08.019] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 06/22/2017] [Accepted: 08/19/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND The short-term effects of low energy availability (EA) on bone metabolism in physically active women and men are currently unknown. PURPOSE We evaluated the effects of low EA on bone turnover markers (BTMs) in a cohort of women and a cohort of men, and compared effects between sexes. METHODS These studies were performed using a randomised, counterbalanced, crossover design. Eleven eumenorrheic women and eleven men completed two 5-day protocols of controlled (CON; 45kcal·kgLBM-1·d-1) and restricted (RES; 15kcal·kgLBM-1·d-1) EAs. Participants ran daily on a treadmill at 70% of their peak aerobic capacity (VO2 peak) resulting in an exercise energy expenditure of 15kcal·kgLBM-1·d-1 and consumed diets providing 60 and 30kcal·kgLBM-1·d-1. Blood was analysed for BTMs [β-carboxyl-terminal cross-linked telopeptide of type I collagen (β-CTX) and amino-terminal propeptide of type 1 procollagen (P1NP)], markers of calcium metabolism [parathyroid hormone (PTH), albumin-adjusted calcium (ACa), magnesium (Mg) and phosphate (PO4)] and regulatory hormones [sclerostin, insulin-like growth factor 1 (IGF-1), triiodothyronine (T3), insulin, leptin, glucagon-like-peptide-2 (GLP-2)]. RESULTS In women, β-CTX AUC was significantly higher (P=0.03) and P1NP AUC was significantly lower (P=0.01) in RES compared to CON. In men, neither β-CTX (P=0.46) nor P1NP (P=0.12) AUCs were significantly different between CON and RES. There were no significant differences between sexes for any BTM AUCs (all P values>0.05). Insulin and leptin AUCs were significantly lower following RES in women only (for both P=0.01). There were no differences in any AUCs of regulatory hormones or markers of calcium metabolism between men and women following RES (all P values>0.05). CONCLUSIONS When comparing within groups, five days of low EA (15kcal·kgLBM-1·d-1) decreased bone formation and increased bone resorption in women, but not in men, and no sex specific differences were detected.
Collapse
Affiliation(s)
- Maria Papageorgiou
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, UK.
| | - Kirsty J Elliott-Sale
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, UK.
| | - Alan Parsons
- School of Health and Social Care, University of Derby, Derby, UK.
| | - Johnathan C Y Tang
- Norwich Medical School, University of East Anglia, UK; Norfolk and Norwich University Hospital, Norfolk, UK.
| | | | - William D Fraser
- Norwich Medical School, University of East Anglia, UK; Norfolk and Norwich University Hospital, Norfolk, UK.
| | - Craig Sale
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, UK.
| |
Collapse
|
10
|
Abstract
The growth hormone/insulin-like growth factor (GH/IGF) axis is critically important for the regulation of bone formation, and deficiencies in this system have been shown to contribute to the development of osteoporosis and other diseases of low bone mass. The GH/IGF axis is regulated by a complex set of hormonal and local factors which can act to regulate this system at the level of the ligands, receptors, IGF binding proteins (IGFBPs), or IGFBP proteases. A combination of in vitro studies, transgenic animal models, and clinical human investigations has provided ample evidence of the importance of the endocrine and local actions of both GH and IGF-I, the two major components of the GH/IGF axis, in skeletal growth and maintenance. GH- and IGF-based therapies provide a useful avenue of approach for the prevention and treatment of diseases such as osteoporosis.
Collapse
Affiliation(s)
- Richard C Lindsey
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA; Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA; Department of Biochemistry, Loma Linda University, Loma Linda, CA 92354, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA; Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA; Department of Biochemistry, Loma Linda University, Loma Linda, CA 92354, USA.
| |
Collapse
|
11
|
Fonseca TL, Teixeira MBCG, Miranda-Rodrigues M, Silva MV, Martins GM, Costa CC, Arita DY, Perez JD, Casarini DE, Brum PC, Gouveia CHA. Thyroid hormone interacts with the sympathetic nervous system to modulate bone mass and structure in young adult mice. Am J Physiol Endocrinol Metab 2014; 307:E408-18. [PMID: 25005498 DOI: 10.1152/ajpendo.00643.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate whether thyroid hormone (TH) interacts with the sympathetic nervous system (SNS) to modulate bone mass and structure, we studied the effects of daily T3 treatment in a supraphysiological dose for 12 wk on the bone of young adult mice with chronic sympathetic hyperactivity owing to double-gene disruption of adrenoceptors that negatively regulate norepinephrine release, α(2A)-AR, and α(2C)-AR (α(2A/2C)-AR(-/-) mice). As expected, T3 treatment caused a generalized decrease in the areal bone mineral density (aBMD) of WT mice (determined by DEXA), followed by deleterious effects on the trabecular and cortical bone microstructural parameters (determined by μCT) of the femur and vertebra and on the biomechanical properties (maximum load, ultimate load, and stiffness) of the femur. Surprisingly, α(2A/2C)-AR(-/-) mice were resistant to most of these T3-induced negative effects. Interestingly, the mRNA expression of osteoprotegerin, a protein that limits osteoclast activity, was upregulated and downregulated by T3 in the bone of α(2A/2C)-AR(-/-) and WT mice, respectively. β1-AR mRNA expression and IGF-I serum levels, which exert bone anabolic effects, were increased by T3 treatment only in α(2A/2C)-AR(-/-) mice. As expected, T3 inhibited the cell growth of calvaria-derived osteoblasts isolated from WT mice, but this effect was abolished or reverted in cells isolated from KO mice. Collectively, these findings support the hypothesis of a TH-SNS interaction to control bone mass and structure of young adult mice and suggests that this interaction may involve α2-AR signaling. Finally, the present findings offer new insights into the mechanisms through which TH regulates bone mass, structure, and physiology.
Collapse
Affiliation(s)
- Tatiana L Fonseca
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Marilia B C G Teixeira
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Marcos V Silva
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gisele M Martins
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Cristiane C Costa
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Danielle Y Arita
- Department of Internal Medicine, Renal Division, Federal University of São Paulo School of Medicine, São Paulo, Brazil; and
| | - Juliana D Perez
- Department of Internal Medicine, Renal Division, Federal University of São Paulo School of Medicine, São Paulo, Brazil; and
| | - Dulce E Casarini
- Department of Internal Medicine, Renal Division, Federal University of São Paulo School of Medicine, São Paulo, Brazil; and
| | - Patricia C Brum
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Cecilia H A Gouveia
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil;
| |
Collapse
|
12
|
Christy AL, D'Souza V, Babu RP, Takodara S, Manjrekar P, Hegde A, Rukmini MS. Utility of C-terminal Telopeptide in Evaluating Levothyroxine Replacement Therapy-Induced Bone Loss. Biomark Insights 2014; 9:1-6. [PMID: 24634578 PMCID: PMC3948734 DOI: 10.4137/bmi.s13965] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Levothyroxine (LT4) therapy has shown to have effects on bone metabolism though its deleterious effect on bone remodeling is debatable. This study was aimed at assessing the diagnostic utility of the bone remodeling marker C-terminal telopeptide (CTx) in detecting early bone loss. MATERIALS AND METHODS In this case-control study, 84 premenopausal women of 30-45 years of age were selected. Out of them, 28 were recently diagnosed of hypothyroidism (not on LT4), 28 were on LT4 replacement therapy (100-200 μg/day) for more than five years, and 28 had euthyroid. Plasma CTx levels were estimated. Bone mineral density (BMD) was measured by quantitative ultrasound (QUS) method. Pearson's coefficient of correlation and ANOVA were used for statistical analysis. RESULTS CTx was most elevated in LT4-treated group (0.497 ± 0.209 ng/mL). It showed a significant negative correlation with T-score and Z-score of BMD values. In the treatment group of more than 150 μg/day, CTx showed significantly negative correlation with TSH (r = -0.462, P = 0.047). CONCLUSION LT4 therapy induces bone loss in hypothyroid patients. CTx levels can measure such bone loss along with BMD. Regular monitoring of CTx with adjustment in LT4 doses may help delay osteoporosis induced by prolonged LT4 replacement therapy.
Collapse
Affiliation(s)
- Alap L Christy
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - Vivian D'Souza
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - Ruby P Babu
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - Sohil Takodara
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - Poornima Manjrekar
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - Anupama Hegde
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| | - M S Rukmini
- Department of Biochemistry, Kasturba Medical College, Manipal University, Mangalore, India
| |
Collapse
|
13
|
Abstract
The importance of the insulin-like growth factor (IGF)-I axis in the regulation of bone size and bone mineral density, two important determinants of bone strength, has been well established from clinical studies involving patients with growth hormone deficiency and IGF-I gene disruption. Data from transgenic animal studies involving disruption and overexpression of components of the IGF-I axis also provide support for a key role for IGF-I in bone metabolism. IGF-I actions in bone are subject to regulation by systemic hormones, local growth factors, as well as mechanical stress. In this review we describe findings from various genetic mouse models that pertain to the role of endocrine and local sources of IGF-I in the regulation of skeletal growth.
Collapse
Affiliation(s)
- Subburaman Mohan
- Musculoskeletal Disease Center, Research Service (151), Jerry L Pettis VA Medical Center, 11201 Benton Street, Loma Linda, CA, 92357, USA.
| | | |
Collapse
|
14
|
Song D, Wang R, Zhong Y, Li W, Li H, Dong F. Locally produced insulin-like growth factor-1 by orbital fibroblasts as implicative pathogenic factor rather than systemically circulated IGF-1 for patients with thyroid-associated ophthalmopathy. Graefes Arch Clin Exp Ophthalmol 2011; 250:433-40. [DOI: 10.1007/s00417-011-1876-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 11/02/2011] [Accepted: 11/15/2011] [Indexed: 11/27/2022] Open
|
15
|
Linares GR, Xing W, Burghardt H, Baumgartner B, Chen ST, Ricart W, Fernández-Real JM, Zorzano A, Mohan S. Role of diabetes- and obesity-related protein in the regulation of osteoblast differentiation. Am J Physiol Endocrinol Metab 2011; 301:E40-8. [PMID: 21467300 PMCID: PMC3129842 DOI: 10.1152/ajpendo.00065.2011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Although thyroid hormone (TH) is known to exert important effects on the skeleton, the nuclear factors constituting the TH receptor coactivator complex and the molecular pathways by which TH mediates its effects on target gene expression in osteoblasts remain poorly understood. A recent study demonstrated that the actions of TH on myoblast differentiation are dependent on diabetes- and obesity-related protein (DOR). However, the role of DOR in osteoblast differentiation is unknown. We found DOR expression increased during in vitro differentiation of bone marrow stromal cells into osteoblasts and also in MC3T3-E1 cells treated with TH. However, DOR expression decreased during cellular proliferation. To determine whether DOR acts as a modulator of TH action during osteoblast differentiation, we examined whether overexpression or knockdown of DOR in MC3T3-E1 cells affects the ability of TH to induce osteoblast differentiation by evaluating alkaline phosphatase (ALP) activity. ALP activity was markedly increased in DOR-overexpressing cells treated with TH. In contrast, loss of DOR dramatically reduced TH stimulation of ALP activity in MC3T3-E1 cells and primary calvaria osteoblasts transduced with lentiviral DOR shRNA. Consistent with reduced ALP activity, mRNA levels of osteocalcin, ALP, and Runx2 were decreased significantly in DOR shRNA cells. In addition, a common single nucleotide polymorphism (SNP), DOR1 found on the promoter of human DOR gene, was associated with circulating osteocalcin levels in nondiabetic subjects. Based on these data, we conclude that DOR plays an important role in TH-mediated osteoblast differentiation, and a DOR SNP associates with plasma osteocalcin in men.
Collapse
Affiliation(s)
- Gabriel R Linares
- Musculoskeletal Disease Center, Jerry L. Pettis Memorial Veterans Affairs Medical Center, Loma Linda, California 92357, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Abstract
Alterations in the hypothalamo-pituitary-thyroid axis have been reported following growth hormone (GH) administration in both adults and children with and without growth hormone deficiency. Reductions in serum free thyroxine (T4), increased tri-iodothyronine (T3) with or without a reduction in serum thyroid-stimulating hormone secretion have been reported following GH replacement, but there are wide inconsistencies in the literature about these perturbations. The clinical significance of these changes in thyroid function remains uncertain. Some authors report the changes are transient and revert to normal after a few months or longer. However, in adult hypopituitary patients, GH replacement has been reported to unmask central hypothyroidism biochemically in 36-47% of apparently euthyroid patients, necessitating thyroxine replacement and resulting in an attenuation of the benefit of GH replacement on quality of life in those who became biochemically hypothyroid after GH replacement. The group at highest risk are those with organic pituitary disease or multiple pituitary hormone deficiencies. It is therefore prudent to monitor thyroid function in hypopituitary patients starting GH therapy to identify those who will develop clinical and biochemical features of central hypothyroidism, thus facilitating optimal and timely replacement.
Collapse
Affiliation(s)
- Lucy Ann Behan
- Academic Department of Endocrinology, Beaumont Hospital, Dublin, Ireland
| | | | | |
Collapse
|
17
|
Abstract
PURPOSE Thyroxine (T4) plays a role in neuroretinal maturation, but little is known regarding its role in retinal vascularization. The neonatal rat retina is incompletely vascularized at birth, providing a model for the human premature infant retina and for retinopathy of prematurity (ROP). We hypothesized that T4 supplementation would accelerate vascular development of normal neonatal rat retina. METHODS Two hundred twenty Sprague-Dawley rats were raised in litters of 10 in room air and received either 0.05 microg/g, 0.5 microg/g, or 1.0 microg/g of intraperitoneal T4 or saline control beginning on day 1 of life for 3 days, 7 days, or 3 days followed by 4 days recovery. Rats were sacrificed on either day 4 or day 8 of life. Left eyes were fixed, retinae dissected and ADPase-stained. Flat mounted retinae were digitized and total retinal areas and retinal vascular density were evaluated in a masked manner. Serum T4, thyroid stimulating hormone (TSH), and insulin-like growth factor-1 (IGF-1) were measured at each time point. RESULTS Retinal vascular density was reduced in animals receiving daily 1 microg/g T4 compared with saline controls after 3 days of T4 (16.8 +/- 1.4 vessels/mm vs. 18.3 +/- 1.3 vessels/mm, p = 0.04) and 7 days of T4 (14.4 +/- 1.3 vessels/mm vs. 16.8 +/- 1.1 vessels/mm, p < 0.0006). However, retinal vascular density returned to normal after 3 days of treatment and 4 days of recovery. Vascularized retinal area was reduced in animals receiving 1 microg/g T4 for 3 days followed by 4 days recovery compared with saline controls (85 +/- 6% vs. 92 +/- 3%, p = 0.002). At lower doses of T4 (0.05 microg/g and 0.5 microg/g for 3 or 7 days) and at 1 microg/g T4 for 7 days, there was no effect on vascularized retinal area. Serum T4 levels were increased, with corresponding TSH suppression, after T4 treatment for 3 or 7 days. Serum IGF-1 levels were unaffected by T4 supplementation. CONCLUSIONS Systemic T4 supplementation at 1 microg/g per day was detrimental to retinal vascular development in neonatal animals. If these effects are paralleled in human neonates, T4 supplementation might increase, rather than decrease, the risk of developing ROP. Further work on the role of T4 in the pathogenesis of ROP is warranted.
Collapse
Affiliation(s)
- Lejla Mutapcic
- Mayo Medical School, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
| | | | | | | | | |
Collapse
|
18
|
Akin F, Yaylali GF, Turgut S, Kaptanoglu B. Growth hormone/insulin-like growth factor axis in patients with subclinical thyroid dysfunction. Growth Horm IGF Res 2009; 19:252-255. [PMID: 19111490 DOI: 10.1016/j.ghir.2008.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Revised: 11/18/2008] [Accepted: 11/19/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Our aim was to evaluate serum concentrations of GH, IGF-I, and insulin-like growth factor-binding protein-3 (IGFBP-3) in patients with subclinical thyroid dysfunction before and after normalization of thyroid function. DESIGN AND METHODS The study included 51 patients (mean age 42.2+/-1.8 years) with subclinical hypothyroidism and 30 patients (mean age 44.3+/-2.4 years) with subclinical hyperthyroidism. A group of 37 euthyroid healthy subjects were studied as controls. Serum concentrations of TSH, FT4, FT3, GH, insulin, IGF-I, and IGFBP-3 were measured in all patients before starting therapy and after normalization of thyroid function. The dosage of levothyroxine (LT4) and antithyroid drugs was adjusted in attempt to keep the serum-free thyroxine (FT4) and thyrotropin (TSH) concentrations within the normal range. MAIN OUTCOME Baseline growth hormone levels were similar with hypothyroid group and hyperthyroid group in relation to euthyroid control subjects. Fasting serum IGF-I levels were significantly lower in the subclinical hypothyroid group compared with the control group. On the other hand, IGF-I levels of subclinical hyperthyroid patients and control group were similar. After normalization of thyroid function tests, IGF-I concentrations were increased in subclinical hypothyroid subjects, but unchanged in subclinical hyperthyroid subjects. Patients with subclinical hyperthyroidism showed slightly lower mean serum IGFBP-3 concentrations than those found in control group, but the difference was not statistically significant. Serum GH and IGFBP-3 levels were unaltered by treatment. CONCLUSIONS In this study, it was shown that GH-IGF axis was not affected in patients with subclinical hyperthyroidism, while it was affected in patients with subclinical hypothyroidism. That is, investigation of the axis in subclinical hyperthyroidism would not bring any extra advantages, but LT4 replacement therapy could prevent abnormalities related to GH-IGF axis in patients with subclinical hypothyroidism.
Collapse
Affiliation(s)
- Fulya Akin
- University of Pamukkale, Faculty of Medicine, Department of Endocrinology and Metabolism, Denizli, Turkey.
| | | | | | | |
Collapse
|
19
|
Abstract
Common diseases result from the complex relationship between genetic and environmental factors. The aim of this review is to provide perspective for a conceptual framework aimed at studying the interplay of gender-specific genetic and environmental factors in the etiology of complex disease, using osteoporosis as an example. In recent years, gender differences in the heritability of the osteoporosis-related phenotypes have been reported and sex-specific quantitative-trait loci were discovered by linkage studies in humans and mice. Results of numerous allelic association studies also differed by gender. In most cases, it was not clear whether or not this phenomenon should be attributed to the effect of sex-chromosomes, sex hormones, or other intrinsic or extrinsic differences between the genders, such as the level of bioavailable estrogen and of physical activity. We conclude that there is need to consider gender-specific genetic and environmental factors in the planning of future association studies on the etiology of osteoporosis and other complex diseases prevalent in the general population.
Collapse
Affiliation(s)
- D Karasik
- Hebrew SeniorLife/IFAR and Harvard Medical School, Boston, MA 02131, USA.
| | | |
Collapse
|
20
|
Abstract
Hyperthyroidism is the most common endocrine disorder of cats, and hypothyroidism is the most common endocrine disorder of dogs. Little is known regarding the effects of hyperthyroidism, hypothyroidism, or treatment of these disorders on calcium metabolism in the dog or cat, however, especially any potential effects on bone. With better diagnostic tools, better treatments, and increased longevity of pets, the clinical impact of thyroid disorders on calcium metabolism and bone may be uncovered.
Collapse
Affiliation(s)
- Patricia A Schenck
- Diagnostic Center for Population and Animal Health, Department of Pathobiology and Diagnostic Investigation, Endocrine Diagnostic Section, Michigan State University, 4125 Beaumont Road, Lansing, MI 48910, USA.
| |
Collapse
|
21
|
Abstract
This article provides a summary of the numerous interactions between the thyroid gland and the skeleton, in the normal state, in disorders of thyroid function and as a result of thyroid malignancy. It recaps the current understanding of bone growth and development in the endochondral growth plate and the normal mechanisms of mature bone remodeling. The actions of thyroid hormones on these processes are described, and the clinical impact of thyroid disorders and their treatments on the bone are summarized. Finally, our current understanding of the physiology of bone metastases from thyroid cancer is covered.
Collapse
Affiliation(s)
- Jason A Wexler
- Division of Endocrinology, MedStar Diabetes and Research Institute, Washington Hospital Center, 110 Irving Street, NW, Room 2A38A, Washington, DC 20010, USA.
| | | |
Collapse
|
22
|
Kindblom JM, Gevers EF, Skrtic SM, Lindberg MK, Göthe S, Törnell J, Vennström B, Ohlsson C. Increased adipogenesis in bone marrow but decreased bone mineral density in mice devoid of thyroid hormone receptors. Bone 2005; 36:607-16. [PMID: 15780976 DOI: 10.1016/j.bone.2005.01.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 12/06/2004] [Accepted: 01/11/2005] [Indexed: 01/02/2023]
Abstract
Mice deficient for all known thyroid hormone receptors, TRalpha1-/-beta-/- mice, display a clear skeletal phenotype characterized by growth retardation, delayed maturation of long bones and decreased trabecular and total bone mineral density (BMD; -14.6 +/- 2.8%, -14.4 +/- 1.5%). The aim of the present study was to investigate the molecular mechanisms behind the skeletal phenotype in TRalpha1-/-beta-/- mice. Global gene expression analysis was performed on total vertebrae from wild-type (WT) and TRalpha1-/-beta-/- mice using DNA microarray and the results were verified by real-time PCR. The mRNA levels of six genes (AdipoQ, Adipsin, Fat-Specific Protein 27 (FSP 27), lipoprotein lipase (LPL), retinol-binding protein (RBP) and phosphoenolpyruvate carboxykinase (PEPCK)) expressed by mature adipocytes were increased in TRalpha1-/-beta-/- compared with WT mice. An increased amount of fat (225% over WT) due to an increased number but unchanged mean size of adipocytes in the bone marrow of TRalpha1-/-beta-/- mice was revealed. Interestingly, the mRNA levels of the key regulator of osteoclastogenesis, receptor activator of NF-varkappab ligand (RANKL), were dramatically decreased in TRalpha1-/-beta-/- mice. In conclusion, TRalpha1-/-beta-/- mice demonstrated increased expression of adipocyte specific genes and an increased amount of bone marrow fat. Thus, these mice have increased adipogenesis in bone marrow associated with decreased trabecular bone mineral density (BMD). One may speculate that these effects either could be caused by an imbalance in the differentiation of the osteoblast and the adipocyte lineages at the expense of osteoblastogenesis, or by independent effects on the regulation of both osteoblastogenesis and adipogenesis.
Collapse
Affiliation(s)
- Jenny M Kindblom
- Center for Bone Research at the Sahlgrenska Academy, RCEM, Department of Internal Medicine, The Sahlgrenska Academy at Gothenburg University, Sweden.
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Zimmermann-Belsing T, Juul A, Juul Holst J, Feldt-Rasmussen U. The insulin-like growth axis in patients with autoimmune thyrotoxicosis: effect of antithyroid drug treatment. Growth Horm IGF Res 2004; 14:235-244. [PMID: 15125885 DOI: 10.1016/j.ghir.2003.12.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Revised: 12/31/2003] [Accepted: 12/31/2003] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Hyperthyroidism is associated with altered growth hormone (GH) secretion. Many patients with thyroid dysfunction experience several poorly described complications such as symptoms and signs also seen in patients with growth hormone deficiency (GHD). We have therefore prospectively evaluated a possible relationship between the thyroid function, body composition, leptin levels and insulin-like growth factor (IGF) related peptides in patients with Graves' disease. DESIGN, PATIENTS, AND MEASUREMENTS: In a prospective group of 24 fasting female patients with Graves' disease (mean age (CI 95%): 40 years (33-47)), we measured serum thyroxine, triiodothyronine, thyrotropine (TSH), TSH receptor antibodies, anti-thyroid peroxidase, leptin, body composition, body mass index (BMI) and IGF-related peptides at diagnosis and after 12 months of treatment with thiamazol (ATD). RESULTS In thyrotoxic patients IGF-I plus IGF-II correlated positively with IGFBP-3 at baseline (r = 0.90, p < 0.1 x 10(16)) and after 12 months follow-up (r = 0.87, p < 0.1 x 10(-16)). In the thyrotoxic state total IGF-I, IGF-II, IGF binding protein 3 (IGFBP-3) and acid-labile subunit (ALS) but not free IGF-I decreased significantly from 223 microg/L (189-260) (mean (CI 95%), 877 microg/L (801-953), 4165 microg/L (3772-4577) and 22 mg/L (18-26)) to 198 microg/L (172-226), 788 microg/L (711-865), 3431 microg/L (3135-3741) and 19 mg/L (16-26) (p <0.006), respectively, after 12 months of ATD despite an increase in BMI from 22 (21-23) to 23 kg/m(2) (22-25) (p < 0.0004) but no significant changes in leptin. CONCLUSIONS The complex IGF systems seemed intact in thyrotoxic patients but change in body composition and the regulation of leptin and insulin secretion during treatment of autoimmune thyroid disease influence IGF-related peptides leaving the patient in a state somewhat similar to partial GHD, but the mechanism behind these alterations remains unclear.
Collapse
Affiliation(s)
- T Zimmermann-Belsing
- Department of Endocrinology, PE-2131, University Hospital, Rigshospitalet, Blegdamsvej 9, Copenhagen DK-2100, Denmark.
| | | | | | | |
Collapse
|
24
|
Freitas FRS, Moriscot AS, Jorgetti V, Soares AG, Passarelli M, Scanlan TS, Brent GA, Bianco AC, Gouveia CHA. Spared bone mass in rats treated with thyroid hormone receptor TR beta-selective compound GC-1. Am J Physiol Endocrinol Metab 2003; 285:E1135-41. [PMID: 12965872 DOI: 10.1152/ajpendo.00506.2002] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Thyrotoxicosis is frequently associated with increased bone turnover and decreased bone mass. To investigate the role of thyroid hormone receptor-beta (TR beta) in mediating the osteopenic effects of triiodothyronine (T3), female adult rats were treated daily (64 days) with GC-1 (1.5 microg/100 g body wt), a TR beta-selective thyromimetic compound. Bone mass was studied by dual-energy X-ray absorptiometry of several skeletal sites and histomorphometry of distal femur, and the results were compared with T3-treated (3 microg/100 g body wt) or control animals. As expected, treatment with T3 significantly reduced bone mineral density (BMD) in the lumbar vertebrae (L2-L5), femur, and tibia by 10-15%. In contrast, GC-1 treatment did not affect the BMD in any of the skeletal sites studied. The efficacy of GC-1 treatment was verified by a reduction in serum TSH (-52% vs. control, P < 0.05) and cholesterol (-21% vs. control, P < 0.05). The histomorphometric analysis of the distal femur indicated that T3 but not GC-1 treatment reduced the trabecular volume, thickness, and number. We conclude that chronic, selective activation of the TR beta isoform does not result in bone loss typical of T3-induced thyrotoxicosis, suggesting that the TR beta isoform is not critical in this process. In addition, our findings suggest that the development of TR-selective T3 analogs that spare bone mass represents a significant improvement toward long-term TSH-suppressive therapy.
Collapse
Affiliation(s)
- Fatima R S Freitas
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, 05508-900, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Mikosch P, Obermayer-Pietsch B, Jost R, Jauk B, Gallowitsch HJ, Kresnik E, Leb G, Lind P. Bone metabolism in patients with differentiated thyroid carcinoma receiving suppressive levothyroxine treatment. Thyroid 2003; 13:347-56. [PMID: 12804103 DOI: 10.1089/105072503321669839] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIM Patients with differentiated thyroid carcinoma (DTC) must receive suppressive levothyroxine (LT(4)) therapy for the rest of their lives. The literature, however, presents conflicting results on how this affects bone metabolism. The aim of this study was to assess the influence of the estrogen status and LT(4) therapy, in particular LT(4) dosage in micrograms per kilograms (microg/kg), on bone metabolism in female patients with DTC. MATERIAL AND METHODS Three markers of bone metabolism (C-terminal telopeptide of type I collagen in serum [SCTx]; N-terminal telopeptide of type I collagen in urine [U-NTx]; and osteocalcin [OC]) were investigated in four groups: group REF (healthy premenopausal female controls), group DTC-ES (premenopausal women with DTC and normal estrogen levels), group DTC-ED (postmenopausal women with DTC and estrogen deficiency), and group DTC-HRT (postmenopausal women with DTC undergoing hormone replacement therapy [HRT]). All patients with DTC were on a well-adjusted suppressive LT(4) therapy with TSH levels 0.1 mU/L or less. RESULTS In group DTC-ES bone turnover was comparable to group REF, whereas in group DTC-ED, all three markers were significantly increased as compared to groups REF and DTC-ES. In group DTC-HRT, the HRT normalized U-NTx and OC. However, in this group S-CTx was not completely normalized by HRT in all patients, although also significantly lowered compared to group DTC-ED. The analysis of LT(4 )dosage per kilogram showed that premenopausal DTC-patients had increased markers of bone metabolism if LT(4) dosage exceeded 2.6 microg/kg. Estrogen-deficient patients with DTC, however, had a much lower critical LT(4) dosage, above which increased markers of bone metabolism were seen. CONCLUSION A well-adjusted suppressive LT(4) therapy of less than 2.6 microg/kg and normal estrogen levels do not seem to increase bone metabolism in estrogen-sufficient patients with DTC. The normalization of an estrogen deficiency by HRT or other antiresorptive therapies and minimal suppressive dosages of LT(4) are attempts to optimize the care of patients with DTC. In postmenopausal patients with DTC and patients with DTC who require LT(4) dosages in excess of 2.6 microg/kg, the information provided by markers of bone metabolism may help to prevent bone damage.
Collapse
Affiliation(s)
- P Mikosch
- Department of Nuclear Medicine and Special Endocrinology, Klagenfurt State Hospital, Austria.
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Iglesias P, Bayón C, Méndez J, Gancedo PG, Grande C, Diez JJ. Serum insulin-like growth factor type 1, insulin-like growth factor-binding protein-1, and insulin-like growth factor-binding protein-3 concentrations in patients with thyroid dysfunction. Thyroid 2001; 11:1043-8. [PMID: 11762714 DOI: 10.1089/105072501753271734] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Thyroid hormones play a role in the regulation of insulin-like growth factor type 1 (IGF-1) and insulin-like growth factor-binding protein-3 (IGFBP-3) expression, and both IGF-1 and IGFBPs have been shown to be related to the function and growth of the thyroid. Our aim was to evaluate serum concentrations of IGF-1, IGFBP-1, and IGFBP-3 in patients with thyroid dysfunction before and after normalization of thyroid function. The study was performed in 86 patients with thyroid dysfunction (43 hyperthyroid and 43 hypothyroid patients) and 17 euthyroid subjects. Serum growth hormone (GH), insulin, IGF-1, IGFBP-1, and IGFBP-3 were measured in all patients before and after normalizing serum thyroid hormone concentrations. Hyperthyroid patients showed IGF-1 (198.8 +/- 17.0 microg/L) and IGFBP-3 levels (4.2 +/- 0.2 mg/L) similar to those found in the control group (217.9 +/- 20.3 microg/L and 4.2 +/- 0.3 mg/L, respectively). After therapy these levels significantly decreased to 156.6 + 11.1 microg/L (p < 0.01) and 3.3 +/- 0.1 mg/L (p < 0.001), respectively. IGFBP-1 concentrations were clearly higher than those found in controls (22.7+/- 2.6 vs. 5.7 +/- 1.5 microg/L, p < 0.001) and exhibited a significant reduction after therapy for thyroid hyperfunction (11.0 +/- 1.7 microg/L, p < 0.001). Patients with hypothyroidism showed serum concentrations of IGF-1 (161.5 +/- 13.1 microg/L, p < 0.05) and IGFBP-3 (3.2 +/- 0.3 microg/L, p < 0.05) significantly lower than those found in healthy volunteers. However, replacement therapy with levothyroxine did not induce any significant modification of these concentrations (152.6 +/- 10.6 microg/L and 3.2 +/- 0.2 mg/L, respectively). Similarly, patients with thyroid hypofunction exhibited raised levels of IGFBP-1 (15.5 +/- 0.9 microg/L, p < 0.05 vs. control group) that were significantly decreased after therapy (8.8 +/- 1.4 microg/L, p < 0.01). The results of the present study show that thyroid status affects GH/IGF axis. Hypothyroidism is associated with significant reductions of IGF-1 and IGFBP-3, and IGFBP-1 is elevated in both hypothyroidism and hyperthyroidism.
Collapse
Affiliation(s)
- P Iglesias
- Department of Endocrinology, Hospital General de Segovia, Madrid, Spain.
| | | | | | | | | | | |
Collapse
|