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Pradhan S, Hon A, Xia Y, Kalanski S, Safvati N, Lu M, Demer LL, Tintut Y. Effects of LP533401 on vascular and bone calcification in hyperlipidemic mice. Biochem Biophys Res Commun 2024; 710:149854. [PMID: 38581947 DOI: 10.1016/j.bbrc.2024.149854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 03/26/2024] [Accepted: 03/27/2024] [Indexed: 04/08/2024]
Abstract
Peripheral serotonin levels are associated with cardiovascular disease risk. We previously found that serum serotonin levels are higher in hyperlipidemic mice than wild-type mice. Evidence also suggests that serotonin regulates biomineralization, in that serotonin treatment augments TNF-a-induced matrix calcification of aortic valve interstitial cells and that a selective inhibitor of peripheral serotonin, LP533401, rescues bone loss induced by ovariectomy in mice. Thus, in the present study, we examined the effects of LP533401 on both skeletal bone mineral density (BMD) and aortic calcification in both young and older hyperlipidemic mice susceptible to calcific atherosclerosis and bone loss. By serial in vivo microCT imaging, we assessed BMD and aortic calcification of Apoe-/- mice fed an atherogenic (high cholesterol) diet alone or mixed with LP533401. Results show that in the young mice, LP533401 blunted skeletal bone loss in lumbar vertebrae but not in femurs. LP533401 also blunted the initial development of aortic calcification but not its progression. Echocardiographic analysis showed that LP533401 blunted both hyperlipidemia-induced cardiac hypertrophy and left ventricular dysfunction. In the older mice, LP533401 increased the BMD of lumbar vertebrae but not of femurs. The aortic calcification progressed in both controls and LP533401-treated mice, but, at post-treatment, LP533401-treated mice had significantly less aortic calcification than the controls. These findings suggest that LP533401 mitigates adverse effects of hyperlipidemia on skeletal and vascular tissues in site- and stage-dependent manners.
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Affiliation(s)
- Stuti Pradhan
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Andy Hon
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yuxuan Xia
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Sophia Kalanski
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nora Safvati
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Mimi Lu
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Linda L Demer
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, USA; Department of Physiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yin Tintut
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; Department of Physiology, University of California, Los Angeles, Los Angeles, CA, USA; Department of Orthopaedic Surgery, University of California, Los Angeles, Los Angeles, CA, USA.
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Tyagi AM. Mechanism of action of gut microbiota and probiotic Lactobacillus rhamnosus GG on skeletal remodeling in mice. Endocrinol Diabetes Metab 2024; 7:e440. [PMID: 37505196 PMCID: PMC10782069 DOI: 10.1002/edm2.440] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/29/2023] Open
Abstract
INTRODUCTION Gut microbiota (GM) is the collection of small organisms such as bacteria, fungi, bacteriophages and protozoans living in the intestine in symbiotics relation within their host. GM regulates host metabolism by various mechanisms. METHODS This review aims to consolidate current information for physicians on the effect of GM on bone health. For this, an online search of the literature was conducted using the keywords gut microbiota, bone mass, osteoporosis, Lactobacillus and sex steroid. RESULTS AND CONCLUSIONS There is a considerable degree of variation in bone mineral density (BMD) within populations, and it is estimated that a significant component of BMD variability is due to genetics. However, the remaining causes of bone mass variance within populations remain largely unknown. A well-recognized cause of phenotypic variation in bone mass is the composition of the microbiome. Studies have shown that germ-free (GF) mice have higher bone mass compared to conventionally raised (CR) mice. Furthermore, GM dysbiosis, also called dysbacteriosis, is defined as any alteration in the composition of the microbial community that has been colonized in the host intestine and associated with the development of bone diseases. For instance, postmenopausal osteoporosis (PMO) and diabetes. GM can be modulated by several factors such as genetics, age, drugs, food habits and probiotics. Probiotics are defined as viable bacteria that confer health benefits by modulating GM when administered in adequate quantity. Lactobacillus rhamnosus GG (LGG) is a great example of such a probiotic. LGG has been shown to regulate bone mass in healthy mice as well as ovariectomized (OVX) mice via two different mechanisms. This review will focus on the literature regarding the mechanism by which GM and probiotic LGG regulate bone mass in healthy mice as well as in OVX mice, a model of PMO.
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Sun K, Wang Y, Du J, Wang Y, Liu B, Li X, Zhang X, Xu X. Exploring the mechanism of traditional Chinese medicine in regulating gut-derived 5-HT for osteoporosis treatment. Front Endocrinol (Lausanne) 2023; 14:1234683. [PMID: 37916145 PMCID: PMC10616894 DOI: 10.3389/fendo.2023.1234683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 09/25/2023] [Indexed: 11/03/2023] Open
Abstract
Osteoporosis is a systemic bone disease characterized by an imbalance in the relationship between osteoblasts, osteocytes, and osteoclasts. This imbalance in bone metabolism results in the destruction of the bone's microstructure and an increase in bone brittleness, thereby increasing the risk of fractures. Osteoporosis has complex causes, one of which is related to the dysregulation of 5-hydroxytryptamine, a neurotransmitter closely associated with bone tissue metabolism. Dysregulation of 5-HT directly or indirectly promotes the occurrence and development of osteoporosis. This paper aims to discuss the regulation of 5-HT by Traditional Chinese Medicine and its impact on bone metabolism, as well as the underlying mechanism of action. The results of this study demonstrate that Traditional Chinese Medicine has the ability to regulate 5-HT, thereby modulating bone metabolism and improving bone loss. These findings provide valuable insights for future osteoporosis treatment.
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Affiliation(s)
- Kai Sun
- The First Department of Orthopedics and Traumatology, The First Affiliated Hospital of Heilongjiang, University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Yincang Wang
- Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Jiazhe Du
- Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Yujie Wang
- Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Bo Liu
- Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Xiaodong Li
- The First Department of Orthopedics and Traumatology, The Third Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Xiaofeng Zhang
- Teaching and Research Section of Orthopedics and Traumatology, Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
| | - Xilin Xu
- The First Department of Orthopedics and Traumatology, The Third Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, Heilongjiang, China
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Niu YB, Zhang YH, Sun Y, Song XZ, Li ZH, Xie M, Mei QB, Li YH, Chen Q. Asperosaponin VI Protects Against Bone Loss Due to Hindlimb Unloading in Skeletally Growing Mice Through Regulating Microbial Dysbiosis Altering the 5-HT Pathway. Calcif Tissue Int 2023; 112:389-402. [PMID: 36595050 DOI: 10.1007/s00223-022-01057-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/21/2022] [Indexed: 01/04/2023]
Abstract
Osteoporosis is a complex multifactorial disease that can lead to an increased risk of fracture. However, selective and effective osteoporosis drugs are still lacking. We showed that Asperosaponin VI (AVI) has the implications to be further developed as an alternative supplement for the prevention and treatment of bone loss. AVI has been found to have beneficial effects on metabolic diseases such as bone loss, obesity, and atherosclerosis. Our study was designed to determine the effect and mechanism of action of AVI against bone loss through regulating microbial dysbiosis. A hindlimb unloading mouse model was established to determine the effect of AVI on bone microarchitecture, gut microbiota, and serum metabolites. Eighteen female C57BL/6 J mice were divided into three groups: control, hindlimb unloading with vehicle (HLU), and hindlimb unloading treated with AVI (HLU-AVI, 200 mg/kg/day). AVI was administrated orally for 4 weeks. The results demonstrated that AVI improved the bone microstructure by reversing the decrease in bone volume fraction and trabecular number, and the increase in trabecular separation and structure model index of cancellous bone in hindlimb suspension mice. The results of 16sRNA gene sequencing suggested that the therapeutic effect of AVI on bone loss may be achieved through it regulating the gut microbiota, especially certain specific microorganisms. Combined with the analysis of ELISA, immunohistochemistry, and serum metabolome results, it could be speculated that AVI played an important role in adjusting the balance of bone metabolism by influencing specific flora such as Clostridium and its metabolites to regulate the 5-hydroxytryptophan pathway. The study explored the novel mechanism of AVI against osteoporosis, and has implications for the further development of AVI as an alternative supplement for the prevention and treatment of bone loss.
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Affiliation(s)
- Y-B Niu
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China
| | - Y-H Zhang
- State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China
| | - Y Sun
- Key Laboratory of Gastrointestinal Pharmacology of Chinese Materia Medica of the State Administration of Traditional Chinese Medicine, Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, Shaanxi, People's Republic of China
| | - X-Z Song
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China
| | - Z-H Li
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China
| | - M Xie
- Department of Pharmacy, The First Naval Force Hospital of Southern Theatre Command, Zhanjiang, 524005, Guangdong, People's Republic of China
| | - Q-B Mei
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China
| | - Y-H Li
- Department of Pathology, The First Naval Force Hospital of Southern Theatre Command, Zhanjiang, 524005, Guangdong, People's Republic of China.
| | - Q Chen
- State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, Shaanxi, People's Republic of China.
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Tu Y, Kuang X, Zhang L, Xu X. The associations of gut microbiota, endocrine system and bone metabolism. Front Microbiol 2023; 14:1124945. [PMID: 37089533 PMCID: PMC10116073 DOI: 10.3389/fmicb.2023.1124945] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/16/2023] [Indexed: 04/25/2023] Open
Abstract
Gut microbiota is of great importance in human health, and its roles in the maintenance of skeletal homeostasis have long been recognized as the "gut-bone axis." Recent evidence has indicated intercorrelations between gut microbiota, endocrine system and bone metabolism. This review article discussed the complex interactions between gut microbiota and bone metabolism-related hormones, including sex steroids, insulin-like growth factors, 5-hydroxytryptamine, parathyroid hormone, glucagon-like peptides, peptide YY, etc. Although the underlying mechanisms still need further investigation, the regulatory effect of gut microbiota on bone health via interplaying with endocrine system may provide a new paradigm for the better management of musculoskeletal disorders.
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Affiliation(s)
- Ye Tu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xinyi Kuang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ling Zhang
- Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- *Correspondence: Ling Zhang,
| | - Xin Xu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
- Xin Xu,
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6
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Study of the biological relevance of Wnt/β-catenin signaling pathway and β-adrenergic regulation in osteoblastic differentiation of mesenchymal stem cells. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Xu Q, Li D, Chen J, Yang J, Yan J, Xia Y, Zhang F, Wang X, Cao H. Crosstalk between the gut microbiota and postmenopausal osteoporosis: Mechanisms and applications. Int Immunopharmacol 2022; 110:108998. [PMID: 35785728 DOI: 10.1016/j.intimp.2022.108998] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/08/2022] [Accepted: 06/21/2022] [Indexed: 12/14/2022]
Abstract
Postmenopausal osteoporosis (PMO) results from a reduction in bone mass and microarchitectural deterioration in bone tissue due to estrogen deficiency, which may increase the incidence of fragility fractures. The number of people suffering from PMO has increased over the years because of the rapidly aging population worldwide. However, several pharmacological agents for the treatment of PMO have many safety risks and impose a heavy financial burden to patients and society. In recent years, the "gut-bone" axis has been proposed as a new approach in the prevention and treatment of PMO. This paper reviews the relationship between the gut microbiota and PMO, which mainly includes the underlying mechanisms between hormones, immunity, nutrient metabolism, metabolites of the gut microbiota and intestinal permeability, and explores the possible role of the gut microbiota in these processes. Finally, we discuss the therapeutic effects of diet, prebiotics, probiotics, and fecal microbiota transplantation on the gut microbiota.
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Affiliation(s)
- Qin Xu
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Dan Li
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Jing Chen
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Nursing Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Ju Yang
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Jiai Yan
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Yanping Xia
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Feng Zhang
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Xuesong Wang
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Department of Orthopedics, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Hong Cao
- Nutrition Department, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Clinical Assessment Center of Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China; Department of Endocrinology, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China.
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8
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Cannon Homaei S, Barone H, Kleppe R, Betari N, Reif A, Haavik J. ADHD symptoms in neurometabolic diseases: Underlying mechanisms and clinical implications. Neurosci Biobehav Rev 2021; 132:838-856. [PMID: 34774900 DOI: 10.1016/j.neubiorev.2021.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/09/2021] [Accepted: 11/09/2021] [Indexed: 12/16/2022]
Abstract
Neurometabolic diseases (NMDs) are typically caused by genetic abnormalities affecting enzyme functions, which in turn interfere with normal development and activity of the nervous system. Although the individual disorders are rare, NMDs are collectively relatively common and often lead to lifelong difficulties and high societal costs. Neuropsychiatric manifestations, including ADHD symptoms, are prominent in many NMDs, also when the primary biochemical defect originates in cells and tissues outside the nervous system. ADHD symptoms have been described in phenylketonuria, tyrosinemias, alkaptonuria, succinic semialdehyde dehydrogenase deficiency, X-linked ichthyosis, maple syrup urine disease, and several mitochondrial disorders, but are probably present in many other NMDs and may pose diagnostic and therapeutic challenges. Here we review current literature linking NMDs with ADHD symptoms. We cite emerging evidence that many NMDs converge on common neurochemical mechanisms that interfere with monoamine neurotransmitter synthesis, transport, metabolism, or receptor functions, mechanisms that are also considered central in ADHD pathophysiology and treatment. Finally, we discuss the therapeutic implications of these findings and propose a path forward to increase our understanding of these relationships.
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Affiliation(s)
- Selina Cannon Homaei
- Division of Psychiatry, Haukeland University Hospital, Norway; Department of Biomedicine, University of Bergen, Norway.
| | - Helene Barone
- Regional Resource Center for Autism, ADHD, Tourette Syndrome and Narcolepsy, Western Norway, Division of Psychiatry, Haukeland University Hospital, Norway.
| | - Rune Kleppe
- Division of Psychiatry, Haukeland University Hospital, Norway; Norwegian Centre for Maritime and Diving Medicine, Department of Occupational Medicine, Haukeland University Hospital, Norway.
| | - Nibal Betari
- Department of Biomedicine, University of Bergen, Norway.
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany.
| | - Jan Haavik
- Division of Psychiatry, Haukeland University Hospital, Norway; Department of Biomedicine, University of Bergen, Norway.
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9
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Kunst RF, Langlais AL, Barlow D, Houseknecht KL, Motyl KJ. Housing Temperature Influences Atypical Antipsychotic Drug-Induced Bone Loss in Female C57BL/6J Mice. JBMR Plus 2021; 5:e10541. [PMID: 34693191 PMCID: PMC8520062 DOI: 10.1002/jbm4.10541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/01/2021] [Accepted: 08/13/2021] [Indexed: 12/15/2022] Open
Abstract
Atypical antipsychotic (AA) drugs, such as risperidone, are associated with endocrine and metabolic side effects, including impaired bone mineral density (BMD) acquisition and increased fracture risk. We have previously shown that risperidone causes bone loss through the sympathetic nervous system and that bone loss is associated with elevated markers of thermogenesis in brown and white adipose tissue. Because rodents are normally housed in sub‐thermoneutral conditions, we wanted to test whether increasing housing temperature would protect against bone loss from risperidone. Four weeks of risperidone treatment in female C57BL/6J mice at thermoneutral (28°C) housing attenuated risperidone‐induced trabecular bone loss and led to a low‐turnover bone phenotype, with indices of both bone formation and resorption suppressed in mice with risperidone treatment at thermoneutrality, whereas indices of bone resorption were elevated by risperidone at room temperature. Protection against trabecular bone loss was not absolute, however, and additional evidence of cortical bone loss emerged in risperidone‐treated mice at thermoneutrality. Taken together, these findings suggest thermal challenge may be in part responsible for bone loss with risperidone treatment and that housing temperature should be considered when assessing bone outcomes of treatments that impact thermogenic pathways. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Roni F Kunst
- Center for Molecular Medicine Maine Medical Center Research Institute Scarborough ME USA
| | - Audrie L Langlais
- Center for Molecular Medicine Maine Medical Center Research Institute Scarborough ME USA.,Graduate School of Biomedical Sciences and Engineering, University of Maine Orono ME USA
| | - Deborah Barlow
- College of Osteopathic Medicine, University of New England Biddeford ME USA
| | | | - Katherine J Motyl
- Center for Molecular Medicine Maine Medical Center Research Institute Scarborough ME USA.,Graduate School of Biomedical Sciences and Engineering, University of Maine Orono ME USA.,Tufts University School of Medicine, Tufts University Boston MA USA
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Liu N, Sun S, Wang P, Sun Y, Hu Q, Wang X. The Mechanism of Secretion and Metabolism of Gut-Derived 5-Hydroxytryptamine. Int J Mol Sci 2021; 22:ijms22157931. [PMID: 34360695 PMCID: PMC8347425 DOI: 10.3390/ijms22157931] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 12/17/2022] Open
Abstract
Serotonin, also known as 5-hydroxytryptamine (5-HT), is a metabolite of tryptophan and is reported to modulate the development and neurogenesis of the enteric nervous system, gut motility, secretion, inflammation, sensation, and epithelial development. Approximately 95% of 5-HT in the body is synthesized and secreted by enterochromaffin (EC) cells, the most common type of neuroendocrine cells in the gastrointestinal (GI) tract, through sensing signals from the intestinal lumen and the circulatory system. Gut microbiota, nutrients, and hormones are the main factors that play a vital role in regulating 5-HT secretion by EC cells. Apart from being an important neurotransmitter and a paracrine signaling molecule in the gut, gut-derived 5-HT was also shown to exert other biological functions (in autism and depression) far beyond the gut. Moreover, studies conducted on the regulation of 5-HT in the immune system demonstrated that 5-HT exerts anti-inflammatory and proinflammatory effects on the gut by binding to different receptors under intestinal inflammatory conditions. Understanding the regulatory mechanisms through which 5-HT participates in cell metabolism and physiology can provide potential therapeutic strategies for treating intestinal diseases. Herein, we review recent evidence to recapitulate the mechanisms of synthesis, secretion, regulation, and biofunction of 5-HT to improve the nutrition and health of humans.
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Affiliation(s)
- Ning Liu
- Key Laboratory of Precision Nutrition and Food Quality, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China;
- Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; (P.W.); (Y.S.); (Q.H.)
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100193, China
| | - Shiqiang Sun
- Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, 9713ZG Groningen, The Netherlands;
- Department of Genetics, University Medical Center Groningen, University of Groningen, 9713ZG Groningen, The Netherlands
| | - Pengjie Wang
- Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; (P.W.); (Y.S.); (Q.H.)
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100193, China
| | - Yanan Sun
- Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; (P.W.); (Y.S.); (Q.H.)
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100193, China
| | - Qingjuan Hu
- Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; (P.W.); (Y.S.); (Q.H.)
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100193, China
| | - Xiaoyu Wang
- Key Laboratory of Precision Nutrition and Food Quality, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China;
- Correspondence: ; Tel.: +86-10-6273-8589
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11
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Zhang Q, Song X, Chen X, Jiang R, Peng K, Tang X, Liu Z. Antiosteoporotic effect of hesperidin against ovariectomy-induced osteoporosis in rats via reduction of oxidative stress and inflammation. J Biochem Mol Toxicol 2021; 35:e22832. [PMID: 34028927 DOI: 10.1002/jbt.22832] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 03/03/2021] [Accepted: 05/18/2021] [Indexed: 01/15/2023]
Abstract
Osteoporosis is a serious health problem, especially in geriatric patients. Worldwide, it affects 8.9 million people every year. Oxidative stress and inflammation expand the osteoporosis reaction. Hesperidin supplement helps to decrease inflammation and oxidative stress. In this study, we estimated the antiosteoporotic effect of hesperidin against the ovariectomized (OVX) rat model of osteoporosis. Hesperidin was orally administered at 5, 10, and 20 mg/kg to OVX rats for 10 weeks. Different biochemical parameters, such as alkaline phosphatase (ALP), osteocalcin (OC), phosphorus (P), calcium (Ca), and antioxidant parameters, were also estimated. The three-point bending test, bone mineral density (BMD), and histomorphometric features of the femoral bone were also scrutinized. Hesperidin significantly decreased body weight and increased uterine weight. Hesperidin significantly reduced the ALP, OC, acid phosphatase, and β-isomerized C-terminal telopeptides levels in OVX rats. Hesperidin considerably increased BMD and dose-dependently reduced the pixel density. Hesperidin considerably increased the maximum load, energy, stiffness, maximum stress, and young modulus. Hesperidin significantly (p < 0.001) reduced the levels of thiobarbituric acid reactive substance and increased the level of superoxide dismutase, glutathione, glutathione peroxidase, catalase in OVX-induced rats. Hesperidin significantly diminishes the cytokine levels, such as tumor necrosis factor-α, interleukin-6 (IL-6), and IL-1β, and inflammatory mediators such as nuclear factor-kappa B. It significantly reduced the level of Ca, P, and increased the level of vitamin D in OVX rats. Hesperidin significantly (p < 0.001) reduced the expression of sirtuin 1. Collectively, we can conclude that hesperidin exhibited better protection against osteoporosis by enhancing the bone density and bone mineral content in addition to biomechanical parameters.
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Affiliation(s)
- Qiang Zhang
- Department of Orthopedics, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Xiaoxia Song
- Department of Respiratory Medicine, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Xiaoming Chen
- Department of Orthopedics, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Ruizhong Jiang
- Department of Orthopedics, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Ke Peng
- Department of Spine Surgery, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Xinqiao Tang
- Department of Orthopedics, Xiangtan Central Hospital, Xiangtan, Hunan, China
| | - Zhong Liu
- Department of Orthopedics, Xiangtan Central Hospital, Xiangtan, Hunan, China
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12
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Wang X, Wang M, Cui X, Li Z, Guo S, Gao F, Ma M, Wang Z. Antiosteoporosis effect of geraniin on ovariectomy-induced osteoporosis in experimental rats. J Biochem Mol Toxicol 2021; 35:1-8. [PMID: 33755276 DOI: 10.1002/jbt.22774] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/23/2021] [Accepted: 03/12/2021] [Indexed: 12/27/2022]
Abstract
Osteoporosis is a skeletal condition that is characterized by decreasing bone density and deteriorating bone mass. The plant-based phytoconstituent such as geraniin possesses better therapeutic potentials in biomedical field. In the current experimental study, we planned to scrutinize the therapeutic potential of geraniin against ovariectomy (OVX)-induced osteoporosis in rats and find the possible mechanism. Healthy Sprague Dawley rats were randomized into six groups and subjected to geraniin and alendronate (ALN) treatment for 10 weeks. Body weight, uterus, femur weight, bone biochemical, bone turnover markers, inflammatory cytokine, calcium, phosphorus, vitamin D (Vit D), urine, hormones, and antioxidant level were estimated. Geraniin significantly (p < .001) reduced the level of bone turnover markers including beta-CrossLaps (β-CTx), ALN, osteocalcin (OC), alkaline phosphatase (ALP), and bone Gla protein (BGP); reduced the biomechanical parameters including maximum load, energy, stiffness, maximum stress, and Young's modulus; reduced the level of calcium (Ca) and phosphorus (P); and increased the level of vitamin D (Vit D) as compared with OVX-induced osteoporosis rats. Geraniin increased the level of bone structure parameters, namely bone mineral density, bone mineral content, tissue mineral density, bone volume fraction, and trabecular number; increased the level of osteoprotegerin (OPG) and OPG/RANKL; and reduced the level of receptor activator of nuclear factor kappa-Β ligand (RANKL). Geraniin significantly (p < .001) increased the level of glutathione (GSH) and reduced the level of malonaldehyde (MDA) in the liver, intestine, and bone of OVX-induced osteoporosis rats. Geraniin significantly (p < .001) decreased the level of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) pro-inflammatory cytokines. We also argue that geraniin could be an excellent candidate to treat and control bone-related disease or disorders.
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Affiliation(s)
- Xiuhui Wang
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Minghui Wang
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Xu Cui
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Zhuokai Li
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Shengyang Guo
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Feng Gao
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Ming Ma
- Department of Orthopaedics, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Zhe Wang
- Department of Orthopaedics, Zhongshan Hospital, Fudan University, Shanghai, China
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13
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Pham HT, Ono M, Hara ES, Nguyen HTT, Dang AT, Do HT, Komori T, Tosa I, Hazehara-Kunitomo Y, Yoshioka Y, Oida Y, Akiyama K, Kuboki T. Tryptophan and Kynurenine Enhances the Stemness and Osteogenic Differentiation of Bone Marrow-Derived Mesenchymal Stromal Cells In Vitro and In Vivo. MATERIALS 2021; 14:ma14010208. [PMID: 33406724 PMCID: PMC7796421 DOI: 10.3390/ma14010208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/17/2020] [Accepted: 12/21/2020] [Indexed: 01/06/2023]
Abstract
Aging tissues present a progressive decline in homeostasis and regenerative capacities, which has been associated with degenerative changes in tissue-specific stem cells and stem cell niches. We hypothesized that amino acids could regulate the stem cell phenotype and differentiation ability of human bone marrow-derived mesenchymal stromal cells (hBMSCs). Thus, we performed a screening of 22 standard amino acids and found that D-tryptophan (10 μM) increased the number of cells positive for the early stem cell marker SSEA-4, and the gene expression levels of OCT-4, NANOG, and SOX-2 in hBMSCs. Comparison between D- and L-tryptophan isomers showed that the latter presents a stronger effect in inducing the mRNA levels of Oct-4 and Nanog, and in increasing the osteogenic differentiation of hBMSCs. On the other hand, L-tryptophan suppressed adipogenesis. The migration and colony-forming ability of hBMSCs were also enhanced by L-tryptophan treatment. In vivo experiments delivering L-tryptophan (50 mg/kg/day) by intraperitoneal injections for three weeks confirmed that L-tryptophan significantly increased the percentage of cells positive for SSEA-4, mRNA levels of Nanog and Oct-4, and the migration and colony-forming ability of mouse BMSCs. L-kynurenine, a major metabolite of L-tryptophan, also induced similar effects of L-tryptophan in enhancing stemness and osteogenic differentiation of BMSCs in vitro and in vivo, possibly indicating the involvement of the kynurenine pathway as the downstream signaling of L-tryptophan. Finally, since BMSCs migrate to the wound healing site to promote bone healing, surgical defects of 1 mm in diameter were created in mouse femur to evaluate bone formation after two weeks of L-tryptophan or L-kynurenine injection. Both L-tryptophan and L-kynurenine accelerated bone healing compared to the PBS-injected control group. In summary, L-tryptophan enhanced the stemness and osteoblastic differentiation of BMSCs and may be used as an essential factor to maintain the stem cell properties and accelerate bone healing and/or prevent bone loss.
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Affiliation(s)
- Hai Thanh Pham
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
- Faculty of Dentistry, Hai Phong University of Medical and Pharmacy, Haiphong 04211, Vietnam
| | - Mitsuaki Ono
- Department of Molecular Biology and Biochemistry, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
- Correspondence: (M.O.); (E.S.H.); Tel.: +81-86-235-7127 (M.O.); +81-86-235-6667 (E.S.H.); Fax: +81-86-222-7768 (M.O.); +81-86-235-6669 (E.S.H.)
| | - Emilio Satoshi Hara
- Department of Biomaterials, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
- Correspondence: (M.O.); (E.S.H.); Tel.: +81-86-235-7127 (M.O.); +81-86-235-6667 (E.S.H.); Fax: +81-86-222-7768 (M.O.); +81-86-235-6669 (E.S.H.)
| | - Ha Thi Thu Nguyen
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
- Faculty of Dentistry, Hai Phong University of Medical and Pharmacy, Haiphong 04211, Vietnam
- Department of Molecular Biology and Biochemistry, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
| | - Anh Tuan Dang
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
- Faculty of Dentistry, Hai Phong University of Medical and Pharmacy, Haiphong 04211, Vietnam
- Department of Molecular Biology and Biochemistry, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
| | - Hang Thuy Do
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
- Faculty of Dentistry, Hai Phong University of Medical and Pharmacy, Haiphong 04211, Vietnam
- Department of Molecular Biology and Biochemistry, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
| | - Taishi Komori
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
| | - Ikue Tosa
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
| | - Yuri Hazehara-Kunitomo
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
- Department of Molecular Biology and Biochemistry, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan
| | - Yuya Yoshioka
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
| | - Yasutaka Oida
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
| | - Kentaro Akiyama
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
| | - Takuo Kuboki
- Department of Oral Rehabilitation and Regenerative Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Okayama 700-8558, Japan; (H.T.P.); (H.T.T.N.); (A.T.D.); (H.T.D.); (T.K.); (I.T.); (Y.H.-K.); (Y.Y.); (Y.O.); (K.A.); (T.K.)
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14
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Mor A, Pawlak K, Kalaska B, Domaniewski T, Sieklucka B, Zieminska M, Cylwik B, Pawlak D. Modulation of the Paracrine Kynurenic System in Bone as a New Regulator of Osteoblastogenesis and Bone Mineral Status in an Animal Model of Chronic Kidney Disease Treated with LP533401. Int J Mol Sci 2020; 21:E5979. [PMID: 32825192 PMCID: PMC7503245 DOI: 10.3390/ijms21175979] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/04/2020] [Accepted: 08/18/2020] [Indexed: 12/21/2022] Open
Abstract
An increase in the peripheral synthesis of serotonin and kynurenine, observed during the chronic kidney disease (CKD) course, is negatively associated with bone health. Serotonin and kynurenine are connected by the common precursor, tryptophan. LP533401 is an inhibitor of peripheral serotonin synthesis. This study aimed to establish if the inhibition of serotonin synthesis by LP533401 may affect the kynurenine pathway activity in bone tissue and its potential consequence with regard to osteogenesis and bone mineral status. Nephrectomized rats were treated with LP533401 at a dose of 30 and 100 mg/kg daily for eight weeks. Tryptophan and kynurenine concentrations were determined, and tryptophan 2,3-dioxygenase (TDO) expression was assessed. We discovered the presence of a TDO-dependent, paracrine kynurenic system in the bone of rats with CKD. Its modulation during LP533401 treatment was associated with impaired bone mineral status. Changes in TDO expression affecting the kynurenine pathway activity were related to the imbalance between peripheral serotonin and 25-hydroxyvitamin D. There were also close associations between the expression of genes participating in osteoblastogenesis and activation of the kynurenine pathway in the bones of LP53301-treated rats. Our results represent the next step in studying the role of tryptophan metabolites in renal osteodystrophy.
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Affiliation(s)
- Adrian Mor
- Department of Pharmacodynamics, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (A.M.); (B.K.); (B.S.)
| | - Krystyna Pawlak
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (K.P.); (T.D.); (M.Z.)
| | - Bartlomiej Kalaska
- Department of Pharmacodynamics, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (A.M.); (B.K.); (B.S.)
| | - Tomasz Domaniewski
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (K.P.); (T.D.); (M.Z.)
| | - Beata Sieklucka
- Department of Pharmacodynamics, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (A.M.); (B.K.); (B.S.)
| | - Marta Zieminska
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (K.P.); (T.D.); (M.Z.)
| | - Bogdan Cylwik
- Department of Paediatric Laboratory Diagnostics, Medical University of Bialystok, Waszyngtona 17, 15-269 Bialystok, Poland;
| | - Dariusz Pawlak
- Department of Pharmacodynamics, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland; (A.M.); (B.K.); (B.S.)
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15
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Discovery and biological characterization of a novel scaffold for potent inhibitors of peripheral serotonin synthesis. Future Med Chem 2020; 12:1461-1474. [DOI: 10.4155/fmc-2020-0127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Aim: Tryptophan hydroxylase 1 (TPH1) catalyzes serotonin synthesis in peripheral tissues. Selective TPH1 inhibitors may be useful for treating disorders related to serotonin dysregulation. Results & methodology: Screening using a thermal shift assay for TPH1 binders yielded Compound 1 (2-(4-methylphenyl)-1,2-benzisothiazol-3(2 H)-one), which showed high potency (50% inhibition at 98 ± 30 nM) and selectivity for inhibiting TPH over related aromatic amino acid hydroxylases in enzyme activity assays. Structure–activity relationships studies revealed several analogs of 1 showing comparable potency. Kinetic studies suggested a noncompetitive mode of action of 1, with regards to tryptophan and tetrahydrobiopterin. Computational docking studies and live cell assays were also performed. Conclusion: This TPH1 inhibitor scaffold may be useful for developing new therapeutics for treating elevated peripheral serotonin.
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16
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Selective serotonin reuptake inhibitors (SSRI) affect murine bone lineage cells. Life Sci 2020; 255:117827. [PMID: 32450170 DOI: 10.1016/j.lfs.2020.117827] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 05/19/2020] [Accepted: 05/19/2020] [Indexed: 11/21/2022]
Abstract
AIMS Data suggest pharmacological treatment of depression with selective serotonin reuptake inhibitors (SSRI) may impair bone health. Our group has previously modeled compromised craniofacial healing after treatment with sertraline, a commonly prescribed SSRI, and hypothesized potential culprits: alterations in bone cells, collagen, and/or inflammation. Here we interrogate bone lineage cell alterations due to sertraline treatment as a potential cause of the noted compromised bone healing. MAIN METHODS Murine pre-osteoblast, pre-osteoclast, osteoblast, and osteoclast cells were treated with clinically relevant concentrations of the SSRI. Studies focused on serotonin pathway targets, cell viability, apoptosis, differentiation, and the osteoblast/osteoclast feedback loop. KEY FINDINGS All cells studied express neurotransmitters (e.g. serotonin transporter, SLC6A4, SSRI target) and G-protein-coupled receptors associated with the serotonin pathway. Osteoclasts presented the greatest native expression of Slc6a4 with all cell types exhibiting decreases in Slc6a4 expression after SSRI treatment. Pre-osteoclasts exhibited alteration to their differentiation pathway after treatment. Pre-osteoblasts and osteoclasts showed reduced apoptosis after treatment but showed no significant differences in functional assays. RANKL OPG mRNA and protein ratios were decreased in the osteoblast lineage. Osteoclast lineage cells treated with sertraline demonstrated diminished TRAP positive cells when pre-exposed to sertraline prior to RANKL-induced differentiation. SIGNIFICANCE These data suggest osteoclasts are a likely target of bone homeostasis disruption due to sertraline treatment, most potently through the osteoblast/clast feedback loop.
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17
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Al Saedi A, Sharma S, Summers MA, Nurgali K, Duque G. The multiple faces of tryptophan in bone biology. Exp Gerontol 2020; 129:110778. [DOI: 10.1016/j.exger.2019.110778] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 11/03/2019] [Accepted: 11/05/2019] [Indexed: 12/11/2022]
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18
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Ogbechi J, Clanchy FI, Huang YS, Topping LM, Stone TW, Williams RO. IDO activation, inflammation and musculoskeletal disease. Exp Gerontol 2019; 131:110820. [PMID: 31884118 DOI: 10.1016/j.exger.2019.110820] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 12/11/2022]
Abstract
The IDO/kynurenine pathway is now established as a major regulator of immune system function. The initial enzyme, indoleamine 2,3-dioxygenase (IDO1) is induced by IFNγ, while tryptophan-2,3-dioxygenase (TDO) is induced by corticosteroids. The pathway is therefore positioned to mediate the effects of systemic inflammation or stress-induced steroids on tissue function and its expression increases with age. Disorders of the musculoskeletal system are a common feature of ageing and many of these conditions are characterized by an inflammatory state. In inflammatory arthritis and related disorders, kynurenine protects against the development of disease, while inhibition or deletion of IDO1 increases its severity. The long-term regulation of autoimmune disorders may be influenced by the epigenetic modulation of kynurenine pathway genes, with recent data suggesting that methylation of IDO may be involved. Osteoporosis is also associated with abnormalities of the kynurenine pathway, reflected in an inversion of the ratio between blood levels of the metabolites anthranilic acid and 3-hydroxy-anthranilic acid. This review discusses evidence to date on the role of the IDO/kynurenine pathway and the highly prevalent age-related disorders of osteoporosis and rheumatoid arthritis and identifies key areas that require further research.
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Affiliation(s)
- Joy Ogbechi
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK
| | - Felix I Clanchy
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK
| | - Yi-Shu Huang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK
| | - Louise M Topping
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK
| | - Trevor W Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK
| | - Richard O Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK.
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19
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Parveen B, Parveen A, Vohora D. Biomarkers of Osteoporosis: An Update. Endocr Metab Immune Disord Drug Targets 2019; 19:895-912. [DOI: 10.2174/1871530319666190204165207] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/16/2018] [Accepted: 01/19/2019] [Indexed: 02/06/2023]
Abstract
Background:
Osteoporosis, characterized by compromised bone quality and strength is
associated with bone fragility and fracture risk. Biomarkers are crucial for the diagnosis or prognosis
of a disease as well as elucidating the mechanism of drug action and improve decision making.
Objective:
An exhaustive description of traditional markers including bone mineral density, vitamin D,
alkaline phosphatase, along with potential markers such as microarchitectural determination, trabecular
bone score, osteocalcin, etc. is provided in the current piece of work. This review provides insight into
novel pathways such as the Wnt signaling pathway, neuro-osseous control, adipogenic hormonal imbalance,
gut-bone axis, genetic markers and the role of inflammation that has been recently implicated
in osteoporosis.
Methods:
We extensively reviewed articles from the following databases: PubMed, Medline and Science
direct. The primary search was conducted using a combination of the following keywords: osteoporosis,
bone, biomarkers, bone turnover markers, diagnosis, density, architecture, genetics, inflammation.
Conclusion:
Early diagnosis and intervention delay the development of disease and improve treatment
outcome. Therefore, probing for novel biomarkers that are able to recognize people at high risk for
developing osteoporosis is an effective way to improve the quality of life of patients and to understand
the pathomechanism of the disease in a better way.
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Affiliation(s)
- Bushra Parveen
- Department of Pharmacology, Pharmaceutical Medicine, School of Pharmaceutical Education and Research, Jamia Hamdard, New-Delhi-10062, India
| | - Abida Parveen
- Department of Clinical Research, School of Interdisciplinary Sciences, Jamia Hamdard, New-Delhi-10062, India
| | - Divya Vohora
- Department of Pharmacology, Pharmaceutical Medicine, School of Pharmaceutical Education and Research, Jamia Hamdard, New-Delhi-10062, India
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20
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Kelly RR, McDonald LT, Jensen NR, Sidles SJ, LaRue AC. Impacts of Psychological Stress on Osteoporosis: Clinical Implications and Treatment Interactions. Front Psychiatry 2019; 10:200. [PMID: 31024360 PMCID: PMC6465575 DOI: 10.3389/fpsyt.2019.00200] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/20/2019] [Indexed: 02/06/2023] Open
Abstract
The significant biochemical and physiological effects of psychological stress are beginning to be recognized as exacerbating common diseases, including osteoporosis. This review discusses the current evidence for psychological stress-associated mental health disorders as risk factors for osteoporosis, the mechanisms that may link these conditions, and potential implications for treatment. Traditional, alternative, and adjunctive therapies are discussed. This review is not intended to provide therapeutic recommendations, but, rather, the goal of this review is to delineate potential interactions of psychological stress and osteoporosis and to highlight potential multi-system implications of pharmacological interventions. Review of the current literature identifies several potentially overlapping mechanistic pathways that may be of interest (e.g., glucocorticoid signaling, insulin-like growth factor signaling, serotonin signaling) for further basic and clinical research. Current literature also supports the potential for cross-effects of therapeutics for osteoporosis and mental health disorders. While studies examining a direct link between osteoporosis and chronic psychological stress are limited, the studies reviewed herein suggest that a multi-factorial, personalized approach should be considered for improved patient outcomes in populations experiencing psychological stress, particularly those at high-risk for development of osteoporosis.
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Affiliation(s)
- Ryan R Kelly
- Research Services, Ralph H. Johnson VA Medical Center, Charleston, SC, United States.,Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Lindsay T McDonald
- Research Services, Ralph H. Johnson VA Medical Center, Charleston, SC, United States.,Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Nathaniel R Jensen
- Research Services, Ralph H. Johnson VA Medical Center, Charleston, SC, United States.,Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Sara J Sidles
- Research Services, Ralph H. Johnson VA Medical Center, Charleston, SC, United States.,Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Amanda C LaRue
- Research Services, Ralph H. Johnson VA Medical Center, Charleston, SC, United States.,Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
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21
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Wadhwa R, Kumar M, Paudel YN, Iqbal R, Kothari P, Trivedi R, Vohora D. Effect of escitalopram and carbidopa on bone markers in Wistar rats: a preliminary experimental study. J Bone Miner Metab 2019; 37:36-42. [PMID: 29380075 DOI: 10.1007/s00774-018-0908-1] [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: 03/08/2017] [Accepted: 01/16/2018] [Indexed: 10/18/2022]
Abstract
In view of the opposite effects of gut and brain serotonin in bone, the key role of Wnt β/catenin pathway in osteoblastic proliferation and the controversial bony effects of selective serotonin reuptake inhibitors antidepressants, the present study investigated the effects of escitalopram alone and in combination with carbidopa (to block gut-derived serotonin) on markers of bone turnover and Wnt signaling and micro-CT in male Wistar rats. Escitalopram (2.0 mg/kg, p.o.) and carbidopa (10 mg/kg, p.o.) were administered daily for 40 days following which indicators of reduced (dickkopf-1, sclerostin), and increased (alkaline phosphatase) bone formation and bone resorption markers (receptor activator of nuclear factor κB ligand, tartrate-resistant acid phosphatase 5b) were determined. Our results indicated that escitalopram adversely affected bone as indicated by reduced bone formation and enhanced bone resorption. Further, the effects of escitalopram on bone formation were possibly mediated through gut serotonin while the mechanisms responsible for effects on resorption seem unrelated to gut serotonin. The promising effects of carbidopa on bone formation, as observed in our study, open up exciting possibilities for this drug requiring further investigations.
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Affiliation(s)
- Ravisha Wadhwa
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Manoj Kumar
- Pharmaceutical Medicine, Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Yam Nath Paudel
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Ramsha Iqbal
- Pharmaceutical Medicine, Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Priyanka Kothari
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Ritu Trivedi
- Endocrinology Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Divya Vohora
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India.
- Pharmaceutical Medicine, Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India.
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22
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Pawlak D, Znorko B, Kalaska B, Domaniewski T, Zawadzki R, Lipowicz P, Doroszko M, Łebkowska U, Grabowski P, Pawlak K. LP533401 restores bone health in 5/6 nephrectomized rats by a decrease of gut-derived serotonin and regulation of serum phosphate through the inhibition of phosphate co-transporters expression in the kidneys. Bone 2018; 113:124-136. [PMID: 29792935 DOI: 10.1016/j.bone.2018.05.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 04/28/2018] [Accepted: 05/20/2018] [Indexed: 11/17/2022]
Abstract
LP533401 is an orally bioavailable small molecule that inhibits tryptophan hydroxylase-1, an enzyme responsible for the synthesis of gut-derived serotonin (GDS). Recently, we showed that increased GDS in rats with chronic kidney disease (CKD) affected bone strength and metabolism. We tested the hypothesis that treatment with LP533401 could reverse CKD-induced bone loss in uremia. Sixteen weeks after 5/6 nephrectomy, rats were randomized into untreated (CKD), treated with vehicle (VEH) and LP533401 at a dose of 30 or 100 mg/kg daily for 8 weeks. Treatment with LP533401 decreased serotonin turnover and restored bone mineral status, microarchitecture, and strength in CKD rats to the values observed in the controls. In parallel with the reduction of serotonin, serum phosphate levels also decreased, particularly in the LP533401, 100 mg/kg group. The mechanism underlying this phenomenon resulted from decreased expression of the renal VDR/FGF1R/Klotho/Npt2a/Npt2c axis, leading to elevated phosphate excretion in the kidneys. The elevated urinary phosphate excretion resulted in improved bone mineral status and strength in LP533401-treated rats. Unexpectedly, the standard VEH used in this model was able to reduce renal VDR/FGF1R/Klotho/Npt2a expression, leading to a compensatory increase in Npt2c mRNA levels, secondary disturbances in phosphate-regulated hormones and partial improvement in the mineral status of the trabecular bone. The decrease of serotonin synthesis together with the simultaneous reduction of renal Npt2a and Npt2c expression in rats treated with LP533401, 100 mg/kg led to an increase in 1,25(OH)2D3 levels; this mechanism seems to be particularly beneficial in relation to the mineral status of cortical bone.
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Affiliation(s)
- Dariusz Pawlak
- Department of Pharmacodynamics, Medical University of Bialystok, Bialystok, Poland
| | - Beata Znorko
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Bialystok, Poland
| | - Bartlomiej Kalaska
- Department of Pharmacodynamics, Medical University of Bialystok, Bialystok, Poland
| | - Tomasz Domaniewski
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Bialystok, Poland
| | - Radosław Zawadzki
- Department of Radiology, Medical University of Bialystok, Bialystok, Poland
| | - Paweł Lipowicz
- Institute of Biocybernetics and Biomedical Engineering, Faculty of Mechanical Engineering, Bialystok University of Technology, Bialystok, Poland
| | - Michał Doroszko
- Department of Mechanics and Applied Computer Science, Faculty of Mechanical Engineering, Bialystok University of Technology, Bialystok, Poland
| | - Urszula Łebkowska
- Department of Radiology, Medical University of Bialystok, Bialystok, Poland
| | - Piotr Grabowski
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Bialystok, Poland
| | - Krystyna Pawlak
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Bialystok, Poland.
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23
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Lavoie B, Roberts JA, Haag MM, Spohn SN, Margolis KG, Sharkey KA, Lian JB, Mawe GM. Gut-derived serotonin contributes to bone deficits in colitis. Pharmacol Res 2018; 140:75-84. [PMID: 30030171 PMCID: PMC6336528 DOI: 10.1016/j.phrs.2018.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/14/2018] [Accepted: 07/16/2018] [Indexed: 02/07/2023]
Abstract
Osteoporosis and bone fractures occur at higher frequency in patients with inflammatory bowel disease (IBD), and decreased bone mass is observed in animal models of colitis. Another consistent feature of colitis is increased serotonin (5-HT) availability in the intestinal mucosa. Since gut-derived 5-HT can decrease bone mass, via activation of 5-HT1B receptors on pre-osteoblasts, we tested the hypothesis that 5-HT contributes to bone loss in colitis. Colitis was chronically induced in mice by adding dextran sodium sulfate (DSS) to their drinking water for 21 days. At day 21, circulating 5-HT levels were elevated in DSS-inflamed mice. Micro-computed tomography of femurs showed a decrease in trabecular bone volume fraction, formation, and surface area, due largely to decreased trabecular numbers in DSS-treated mice. The colitis-induced loss of trabecular bone was significantly suppressed in mice treated with the 5-HT synthesis inhibitor, p-chloro-DL-phenylalanine (PCPA; 300 mg/kg/day IP daily), and in mice treated with the 5-HT1B receptor antagonist GR55562 (1 mg/Kg/day SC daily). The 5-HT reuptake transporter (SERT) is critical for moving 5-HT from the interstitial space into enterocytes and from serum into platelets. Mice lacking SERT exhibited significant deficits in trabecular bone mass that are similar to those observed in DSS-inflamed mice, and these deficits were not extensively worsened by DSS-induced colitis in the SERT-/- mice. Taken together, findings from both the DSS and SERT-/- mouse models support a contributing role for 5-HT as a significant factor in bone loss induced by colitis.
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Affiliation(s)
- B Lavoie
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, USA.
| | - J A Roberts
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, USA
| | - M M Haag
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, USA
| | - S N Spohn
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, USA
| | - K G Margolis
- Department of Pediatrics, Columbia University, New York, NY, USA
| | - K A Sharkey
- Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - J B Lian
- Department of Biochemistry, The University of Vermont, Burlington, VT, USA
| | - G M Mawe
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, USA
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24
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Lavoie B, Lian JB, Mawe GM. Regulation of Bone Metabolism by Serotonin. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1033:35-46. [PMID: 29101650 DOI: 10.1007/978-3-319-66653-2_3] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The processes of bone growth and turnover are tightly regulated by the actions of various signaling molecules, including hormones, growth factors, and cytokines. Imbalances in these processes can lead to skeletal disorders such as osteoporosis or high bone mass disease. It is becoming increasingly clear that serotonin can act through a number of mechanisms, and at different locations in the body, to influence the balance between bone formation and resorption. Its actions on bone metabolism can vary, based on its site of synthesis (central or peripheral) as well as the cells and subtypes of receptors that are activated. Within the central nervous system, serotonergic neurons act via the hypothalamus to suppress sympathetic input to the bone. Since sympathetic input inhibits bone formation, brain serotonin has a net positive effect on bone growth. Gut-derived serotonin is thought to inhibit bone growth by attenuating osteoblast proliferation via activation of receptors on pre-osteoblasts. There is also evidence that serotonin can be synthesized within the bone and act to modulate bone metabolism. Osteoblasts, osteoclasts, and osteocytes all have the machinery to synthesize serotonin, and they also express the serotonin-reuptake transporter (SERT). Understanding the roles of serotonin in the tightly balanced system of bone modeling and remodeling is a clinically relevant goal. This knowledge can clarify bone-related side effects of drugs that affect serotonin signaling, including serotonin-specific reuptake inhibitors (SSRIs) and receptor agonists and antagonists, and it can potentially lead to therapeutic approaches for alleviating bone pathologies.
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Affiliation(s)
- Brigitte Lavoie
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, 05405, USA. .,The University of Vermont, D406 Given Building, Burlington, VT, 05405, USA.
| | - Jane B Lian
- Department of Biochemistry, The University of Vermont, Burlington, VT, 05405, USA
| | - Gary M Mawe
- Department of Neurological Sciences, The University of Vermont, Burlington, VT, 05405, USA
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25
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Matthes S, Bader M. Peripheral Serotonin Synthesis as a New Drug Target. Trends Pharmacol Sci 2018; 39:560-572. [PMID: 29628275 DOI: 10.1016/j.tips.2018.03.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/19/2022]
Abstract
The first step in serotonin (5-HT) biosynthesis is catalyzed by tryptophan hydroxylase (TPH). There are two independent sources of the monoamine that have distinct functions: first, the TPH1-expressing enterochromaffin cells (ECs) of the gut; second, TPH2-expressing serotonergic neurons. TPH1-deficient mice revealed that peripheral 5-HT plays important roles in platelet function and in inflammatory and fibrotic diseases of gut, pancreas, lung, and liver. Therefore, TPH inhibitors were developed which cannot pass the blood-brain barrier to specifically block peripheral 5-HT synthesis. They showed therapeutic efficacy in several rodent disease models, and telotristat ethyl is the first TPH inhibitor to be approved for the treatment of carcinoid syndrome. We review this development and discuss further therapeutic options for these compounds.
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Affiliation(s)
- Susann Matthes
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Berlin Institute of Health (BIH), Anna-Louisa-Karsch-Straße 2, 10178 Berlin, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany.
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26
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Marie PJ, Cohen-Solal M. The Expanding Life and Functions of Osteogenic Cells: From Simple Bone-Making Cells to Multifunctional Cells and Beyond. J Bone Miner Res 2018; 33:199-210. [PMID: 29206311 DOI: 10.1002/jbmr.3356] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/27/2017] [Accepted: 11/29/2017] [Indexed: 12/20/2022]
Abstract
During the last three decades, important progress in bone cell biology and in human and mouse genetics led to major advances in our understanding of the life and functions of cells of the osteoblast lineage. Previously unrecognized sources of osteogenic cells have been identified. Novel cellular and molecular mechanisms controlling osteoblast differentiation and senescence have been determined. New mechanisms of communications between osteogenic cells, osteocytes, osteoclasts, and chondrocytes, as well as novel links between osteogenic cells and blood vessels have been identified. Additionally, cells of the osteoblast lineage were shown to be important components of the hematopoietic niche and to be implicated in hematologic dysfunctions and malignancy. Lastly, unexpected interactions were found between osteogenic cells and several soft tissues, including the central nervous system, gut, muscle, fat, and testis through the release of paracrine factors, making osteogenic cells multifunctional regulatory cells, in addition to their bone-making function. These discoveries considerably enlarged our vision of the life and functions of osteogenic cells, which may lead to the development of novel therapeutics with immediate applications in bone disorders. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Pierre J Marie
- Inserm UMR-1132, Paris, France.,University Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Martine Cohen-Solal
- Inserm UMR-1132, Paris, France.,University Paris Diderot, Sorbonne Paris Cité, Paris, France
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27
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Yang T, Williams BO. Low-Density Lipoprotein Receptor-Related Proteins in Skeletal Development and Disease. Physiol Rev 2017; 97:1211-1228. [PMID: 28615463 DOI: 10.1152/physrev.00013.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 03/07/2017] [Accepted: 03/15/2017] [Indexed: 02/06/2023] Open
Abstract
The identification of the low-density lipoprotein receptor (LDLR) provided a foundation for subsequent studies in lipoprotein metabolism, receptor-mediated endocytosis, and many other fundamental biological functions. The importance of the LDLR led to numerous studies that identified homologous molecules and ultimately resulted in the description of the LDL-receptor superfamily, a group of proteins that contain domains also found in the LDLR. Subsequent studies have revealed that members of the LDLR-related protein family play roles in regulating many aspects of signal transduction. This review is focused on the roles of selected members of this protein family in skeletal development and disease. We present background on the identification of this subgroup of receptors, discuss the phenotypes associated with alterations in their function in human patients and mouse models, and describe the current efforts to therapeutically target these proteins to treat human skeletal disease.
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Affiliation(s)
- Tao Yang
- Program in Skeletal Disease and Tumor Microenvironment, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan
| | - Bart O Williams
- Program in Skeletal Disease and Tumor Microenvironment, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan
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28
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Abstract
The gut microbiota (GM) is an important regulator of body homeostasis, including intestinal and extra-intestinal effects. This review focuses on the GM-bone axis, which we define as the effect of the gut-associated microbial community or the molecules they synthesize, on bone health. While research in this field is limited, findings from preclinical studies support that gut microbes positively impact bone mineral density and strength parameters. Moreover, administration of beneficial bacteria (probiotics) in preclinical models has demonstrated higher bone mineralization and greater bone strength. The preferential bacterial genus that has shown these beneficial effects in bone is Lactobacillus and thus lactobacilli are among the best candidates for future clinical intervention trials. However, their effectiveness is dependent on stage of development, as early life constitutes an important time for impacting bone health, perhaps via modulation of the GM. In addition, sex-specific difference also impacts the efficacy of the probiotics. Although auspicious, many questions regarding the GM-bone axis require consideration of potential mechanisms; sex-specific efficacy; effective dose of probiotics; and timing and duration of treatment.
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Affiliation(s)
- Christopher R Villa
- a Department of Nutritional Sciences , University of Toronto , Toronto , Ontario , Canada
| | - Wendy E Ward
- a Department of Nutritional Sciences , University of Toronto , Toronto , Ontario , Canada.,b Department of Kinesiology , Brock University , St. Catharines , Ontario , Canada
| | - Elena M Comelli
- a Department of Nutritional Sciences , University of Toronto , Toronto , Ontario , Canada
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29
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Waløen K, Kleppe R, Martinez A, Haavik J. Tyrosine and tryptophan hydroxylases as therapeutic targets in human disease. Expert Opin Ther Targets 2016; 21:167-180. [PMID: 27973928 DOI: 10.1080/14728222.2017.1272581] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The ancient and ubiquitous monoamine signalling molecules serotonin, dopamine, norepinephrine, and epinephrine are involved in multiple physiological functions. The aromatic amino acid hydroxylases tyrosine hydroxylase (TH), tryptophan hydroxylase 1 (TPH1), and tryptophan hydroxylase 2 (TPH2) catalyse the rate-limiting steps in the biosynthesis of these monoamines. Genetic variants of TH, TPH1, and TPH2 genes are associated with neuropsychiatric disorders. The interest in these enzymes as therapeutic targets is increasing as new roles of these monoamines have been discovered, not only in brain function and disease, but also in development, cardiovascular function, energy and bone homeostasis, gastrointestinal motility, hemostasis, and liver function. Areas covered: Physiological roles of TH, TPH1, and TPH2. Enzyme structures, catalytic and regulatory mechanisms, animal models, and associated diseases. Interactions with inhibitors, pharmacological chaperones, and regulatory proteins relevant for drug development. Expert opinion: Established inhibitors of these enzymes mainly target their amino acid substrate binding site, while tetrahydrobiopterin analogues, iron chelators, and allosteric ligands are less studied. New insights into monoamine biology and 3D-structural information and new computational/experimental tools have triggered the development of a new generation of more selective inhibitors and pharmacological chaperones. The enzyme complexes with their regulatory 14-3-3 proteins are also emerging as therapeutic targets.
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Affiliation(s)
- Kai Waløen
- a Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders , University of Bergen , Bergen , Norway
| | - Rune Kleppe
- b Computational Biology Unit, Department of Informatics , University of Bergen , Bergen , Norway
| | - Aurora Martinez
- a Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders , University of Bergen , Bergen , Norway
| | - Jan Haavik
- a Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders , University of Bergen , Bergen , Norway
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30
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Wei QS, Chen ZQ, Tan X, Kang LC, Jiang XB, Liang J, He W, Deng WM. Serum serotonin concentration associated with bone mineral density in Chinese postmenopausal women. Scand J Clin Lab Invest 2016; 77:40-44. [PMID: 27826984 DOI: 10.1080/00365513.2016.1247983] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Recent studies have shown that circulating serotonin plays a potential role in bone metabolism. However, conflicting results have been reported for the relationship between serum serotonin concentrations and bone mineral density (BMD). We investigated whether the serum serotonin concentrations related to BMD in Chinese postmenopausal women. Serum serotonin and bone turnover concentrations of 117 premenopausal women and 262 asymptomatic postmenopausal women were analyzed by enzyme-linked immunosorbent assay. BMD at the lumbar spine and femoral neck was measured by dual energy X-ray absorptiometry. The relationship between serotonin and BMD was investigated. The postmenopausal women had lower mean serum serotonin concentrations compared to the premenopausal women. Serotonin concentrations were negatively associated with age, weight, BMI, fat mass, and β-CTX concentrations in postmenopausal women. No significant correlations were found between serotonin and these parameters in premenopausal women. In postmenopausal women, age- and BMI-adjusted serotonin concentrations were positively correlated with BMD of the lumbar spine and femoral neck. Multiple regression analyses showed serum serotonin and β-CTX were the predictors for lumbar spine BMD. Only serum serotonin was the determinant for femoral neck BMD. In conclusion, lower serum serotonin concentrations are linked to low lumbar spine and femoral neck BMD in postmenopausal women.
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Affiliation(s)
- Qiu-Shi Wei
- a Department of Orthopaedics Surgery , The First Affiliated Hospital of Guangzhou University of Chinese Medicine , Guangzhou , P. R. China.,b Key Laboratory of Orthopaedics & Traumatology , Guangzhou University of Chinese Medicine , Guangzhou , P. R. China
| | - Zhen-Qiu Chen
- a Department of Orthopaedics Surgery , The First Affiliated Hospital of Guangzhou University of Chinese Medicine , Guangzhou , P. R. China
| | - Xin Tan
- c Department of Six Internal Medicine , General Hospital of Guangzhou Military Command of PLA , Guangzhou , P. R. China
| | - Lu-Chen Kang
- c Department of Six Internal Medicine , General Hospital of Guangzhou Military Command of PLA , Guangzhou , P. R. China
| | - Xiao-Bing Jiang
- a Department of Orthopaedics Surgery , The First Affiliated Hospital of Guangzhou University of Chinese Medicine , Guangzhou , P. R. China
| | - Jiang Liang
- d Department of Rheumatology , The Second Affiliated Hospital of Guiyang University of Chinese Medicine , Guizhou , P. R. China
| | - Wei He
- a Department of Orthopaedics Surgery , The First Affiliated Hospital of Guangzhou University of Chinese Medicine , Guangzhou , P. R. China.,b Key Laboratory of Orthopaedics & Traumatology , Guangzhou University of Chinese Medicine , Guangzhou , P. R. China
| | - Wei-Min Deng
- c Department of Six Internal Medicine , General Hospital of Guangzhou Military Command of PLA , Guangzhou , P. R. China
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31
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Lima GMG, Corazza BJM, Moraes RM, de Oliveira FE, de Oliveira LD, Franco GCN, Perrien DS, Elefteriou F, Anbinder AL. The effect of an inhibitor of gut serotonin (LP533401) during the induction of periodontal disease. J Periodontal Res 2016; 51:661-8. [PMID: 26740292 DOI: 10.1111/jre.12346] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVE LP533401 is an inhibitor of tryptophan hydroxylase 1, which regulates serotonin production in the gut. Previous work indicates that LP533401 has an anabolic effect in bone. Thus, we hypothesized that inhibition of gut serotonin production may modulate the host response in periodontal disease. In this study, we aimed to analyze the effects of LP533401 in a rat periodontitis model to evaluate the role of gut serotonin in periodontitis pathophysiology. MATERIAL AND METHODS Twenty-four rats were divided into three groups: treated group (T: ligature-induced periodontal disease and LP533401, 25 mg/kg/d) by gavage; ligature group (L: ligature-induced periodontal disease only); and control group (C: without ligature-induced periodontal disease). After 28 d, radiographic alveolar bone support was measured on digital radiographs, and alveolar bone volume fraction, tissue mineral density and trabeculae characteristics were quantified by microcomputed tomography in the right hemi-mandible. Left hemi-mandibles were decalcified and alveolar bone loss, attachment loss and area of collagen in the gingiva were histologically analyzed. RESULTS Significant difference between the L and C groups was found, confirming that periodontal disease was induced. We observed no difference between the T and L groups regarding alveolar bone destruction and area of collagen. CONCLUSION LP533401 (25 mg/kg/d) for 28 d does not prevent bone loss and does not modulate host response in a rat model of induced periodontal disease.
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Affiliation(s)
- G M G Lima
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
| | - B J M Corazza
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
| | - R M Moraes
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
| | - F E de Oliveira
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
| | - L D de Oliveira
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
| | - G C N Franco
- Department of General Biology, State University of Ponta Grossa - UEPG, Ponta Grossa, Paraná, Brazil
| | - D S Perrien
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Orthopedic Surgery & Rehabilitation and Vanderbilt University Institute of Imaging Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
| | - F Elefteriou
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, USA.,Departments of Medicine, Pharmacology and Cancer Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - A L Anbinder
- Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos, Univ Estadual Paulista - UNESP, São José dos Campos, SP, Brazil
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32
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Fu HJ, Zhao Y, Zhou YR, Bao BH, Du Y, Li JX. Ursolic acid derivatives as bone anabolic agents targeted to tryptophan hydroxylase 1 (Tph-1). Eur J Pharm Sci 2015; 76:33-47. [PMID: 25930119 DOI: 10.1016/j.ejps.2015.04.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 04/15/2015] [Accepted: 04/26/2015] [Indexed: 01/28/2023]
Abstract
Tryptophan hydroxylase 1 (Tph-1) initiates the biosynthesis of peripheral serotonin. As peripheral serotonin suppresses bone formation, inhibitor of Tph-1 provides a useful tool to discover anabolic agents for osteoporosis. In the present study, series of ursolic acid (UA) derivatives were synthesized, and their inhibitory activity on serotonin biosynthesis and cytotoxicity were evaluated. Among the derivatives, 8d with potent inhibitory activity on serotonin was applied for further research. The data revealed that 8d significantly inhibited protein and mRNA expressions of Tph-1, and an SPR study indicated that 8d directly interacted to Tph-1 with a binding affinity of KD=15.09μM. Oral administration of 8d significantly prevented bone loss via suppressing serotonin biosynthesis without estrogenic side-effects in ovariectomized (OVX) rats.
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Affiliation(s)
- Hai-Jian Fu
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China
| | - Yang Zhao
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China
| | - Yu-Ren Zhou
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China
| | - Bei-Hua Bao
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China
| | - Yun Du
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China
| | - Jian-Xin Li
- State Key Lab of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, PR China.
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33
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El-Merahbi R, Löffler M, Mayer A, Sumara G. The roles of peripheral serotonin in metabolic homeostasis. FEBS Lett 2015; 589:1728-34. [PMID: 26070423 DOI: 10.1016/j.febslet.2015.05.054] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 05/26/2015] [Accepted: 05/30/2015] [Indexed: 11/30/2022]
Abstract
Metabolic homeostasis in the organism is assured both by the nervous system and by hormones. Among a plethora of hormones regulating metabolism, serotonin presents a number of unique features. Unlike classical hormones serotonin is produced in different anatomical locations. In brain it acts as a neurotransmitter and in the periphery it can act as a hormone, auto- and/or paracrine factor, or intracellular signaling molecule. Serotonin does not cross the blood-brain barrier; therefore the two major pools of this bioamine remain separated. Although 95% of serotonin is produced in the periphery, its functions have been ignored until recently. Here we review the impact of the peripheral serotonin on the regulation of function of the organs involved in glucose and lipid homeostasis.
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Affiliation(s)
- Rabih El-Merahbi
- Rudolf Virchow Center for Experimental Biomedicine University of Würzburg, Josef-Schneider-Str. 2, Haus D15, D-97080 Würzburg, Germany
| | - Mona Löffler
- Rudolf Virchow Center for Experimental Biomedicine University of Würzburg, Josef-Schneider-Str. 2, Haus D15, D-97080 Würzburg, Germany
| | - Alexander Mayer
- Rudolf Virchow Center for Experimental Biomedicine University of Würzburg, Josef-Schneider-Str. 2, Haus D15, D-97080 Würzburg, Germany
| | - Grzegorz Sumara
- Rudolf Virchow Center for Experimental Biomedicine University of Würzburg, Josef-Schneider-Str. 2, Haus D15, D-97080 Würzburg, Germany.
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Kartner N, Manolson MF. Novel techniques in the development of osteoporosis drug therapy: the osteoclast ruffled-border vacuolar H(+)-ATPase as an emerging target. Expert Opin Drug Discov 2014; 9:505-22. [PMID: 24749538 DOI: 10.1517/17460441.2014.902155] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Bone loss occurs in many diseases, including osteoporosis, rheumatoid arthritis and periodontal disease. For osteoporosis alone, it is estimated that 75 million people are afflicted worldwide, with high risks of fractures and increased morbidity and mortality. The demand for treatment consumes an ever-increasing share of healthcare resources. Successive generations of antiresorptive bisphosphonate drugs have reduced side effects, minimized frequency of dosing, and increased efficacy in halting osteoporotic bone loss, but their shortcomings have remained significant to the extent that a monoclonal antibody antiresorptive has recently taken a significant market share. Yet this latter, paradigm-shifting approach has its own drawbacks. AREAS COVERED This review summarizes recent literature on bone-remodeling cell and molecular biology and the background for existing approaches and emerging therapeutics and targets for treating osteoporosis. The authors discuss vacuolar H(+)-ATPase (V-ATPase) molecular biology and the recent advances in targeting the osteoclast ruffled-border V-ATPase (ORV) for the development of novel antiresorptive drugs. They also cover examples from the V-ATPase-targeted drug discovery literature, including conventional molecular biology methods, in silico drug discovery, and gene therapy in more detail as proofs of concept. EXPERT OPINION Existing therapeutic options for osteoporosis have limitations and inherent drawbacks. Thus, the search for novel approaches to osteoporosis drug discovery remains relevant. Targeting the ORV may be one of the more selective means of regulating bone resorption. Furthermore, this approach may be effective without removing active osteoclasts from the finely balanced osteoclast-osteoblast coupling required for normal bone remodeling.
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Affiliation(s)
- Norbert Kartner
- University of Toronto , 124 Edward Street, Toronto, Ontario M5G 1G6 , Canada
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Selective serotonin reuptake inhibitor exposure alters osteoblast gene expression and craniofacial development in mice. ACTA ACUST UNITED AC 2014; 100:912-23. [DOI: 10.1002/bdra.23323] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zhong Z, Ethen NJ, Williams BO. WNT signaling in bone development and homeostasis. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2014; 3:489-500. [PMID: 25270716 DOI: 10.1002/wdev.159] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Revised: 08/16/2014] [Accepted: 08/25/2014] [Indexed: 01/29/2023]
Abstract
The balance between bone formation and bone resorption controls postnatal bone homeostasis. Research over the last decade has provided a vast amount of evidence that WNT signaling plays a pivotal role in regulating this balance. Therefore, understanding how the WNT signaling pathway regulates skeletal development and homeostasis is of great value for human skeletal health and disease.
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Affiliation(s)
- Zhendong Zhong
- Center for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA
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Abstract
The bone marrow niche is thought to act as a permissive microenvironment required for emergence or progression of hematologic cancers. We hypothesized that osteoblasts, components of the niche involved in hematopoietic stem cell (HSC) function, influence the fate of leukemic blasts. We show that osteoblast numbers decrease by 55% in myelodysplasia and acute myeloid leukemia patients. Further, genetic depletion of osteoblasts in mouse models of acute leukemia increased circulating blasts and tumor engraftment in the marrow and spleen leading to higher tumor burden and shorter survival. Myelopoiesis increased and was coupled with a reduction in B lymphopoiesis and compromised erythropoiesis, suggesting that hematopoietic lineage/progression was altered. Treatment of mice with acute myeloid or lymphoblastic leukemia with a pharmacologic inhibitor of the synthesis of duodenal serotonin, a hormone suppressing osteoblast numbers, inhibited loss of osteoblasts. Maintenance of the osteoblast pool restored normal marrow function, reduced tumor burden, and prolonged survival. Leukemia prevention was attributable to maintenance of osteoblast numbers because inhibition of serotonin receptors alone in leukemic blasts did not affect leukemia progression. These results suggest that osteoblasts play a fundamental role in propagating leukemia in the marrow and may be a therapeutic target to induce hostility of the niche to leukemia blasts.
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Gupta S, Ahsan I, Mahfooz N, Abdelhamid N, Ramanathan M, Weinstock-Guttman B. Osteoporosis and multiple sclerosis: risk factors, pathophysiology, and therapeutic interventions. CNS Drugs 2014; 28:731-42. [PMID: 24871932 DOI: 10.1007/s40263-014-0173-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory-demyelinating disease of the nervous system. There has been mounting evidence showing that MS is associated with increased risk of osteoporosis and fractures. The development of osteoporosis in MS patients can be related to the cumulative effects of various factors. This review summarizes the common risk factors and physiologic pathways that play a role in development of osteoporosis in MS patients. Physical inactivity and reduced mechanical load on the bones (offsetting gravity) is likely the major contributing factor for osteoporosis in MS. Additional possible factors leading to reduced bone mass are low vitamin D levels, and use of medications such as glucocorticoids and anticonvulsants. The role of the inflammatory processes related to the underlying disease is considered in the context of the complex bone metabolism. The known effect of different MS disease-modifying therapies on bone health is limited. An algorithm for diagnosis and management of osteoporosis in MS is proposed.
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Affiliation(s)
- Sahil Gupta
- Department of Neurology, State University of New York, Buffalo, NY, USA
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Abstract
Fat and bone have a complicated relationship. Although obesity has been associated with low fracture risk, there is increasing evidence that some of the factors that are released by peripheral fat into the circulation may also have a deleterious effect on bone mass, thus, predisposing to fractures. More importantly, the local interaction between fat and bone within the bone marrow seems to play a significant role in the pathogenesis of age-related bone loss and osteoporosis. This "local interaction" occurs inside the bone marrow and is associated with the autocrine and paracrine release of fatty acids and adipokines, which affect the cells in their vicinity including the osteoblasts, reducing their function and survival. In this review, we explore the particularities of the fat and bone cell interactions within the bone marrow, their significance in the pathogenesis of osteoporosis, and the potential therapeutic applications that regulating marrow fat may have in the near future as a novel pharmacologic treatment for osteoporosis.
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Affiliation(s)
- Sandra Bermeo
- Ageing Bone Research Program, Sydney Medical School Nepean, The University of Sydney, Level 5, South Block, Nepean Hospital, Penrith, NSW., Australia, 2750
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Lee GS, Simpson C, Sun BH, Yao C, Foer D, Sullivan B, Matthes S, Alenina N, Belsky J, Bader M, Insogna KL. Measurement of plasma, serum, and platelet serotonin in individuals with high bone mass and mutations in LRP5. J Bone Miner Res 2014; 29:976-81. [PMID: 24038240 PMCID: PMC3935983 DOI: 10.1002/jbmr.2086] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 08/12/2013] [Accepted: 08/17/2013] [Indexed: 11/08/2022]
Abstract
It has recently been suggested that the low-density lipoprotein receptor-related protein 5 (LRP5) regulates bone mass by suppressing secretion of serotonin from duodenal enterochromaffin cells. In mice with targeted expression of a high bone mass-causing (HBM-causing) LRP5 mutation and in humans with HBM LRP5 mutations, circulating serotonin levels have been reported to be lower than in controls whereas individuals with loss-of-function mutations in LRP5 have high blood serotonin. In contrast, others have reported that conditionally activating a knock-in allele of an HBM-causing LRP5 mutation in several tissues, or genetic deletion of LRP5 in mice has no effect on serum serotonin levels. To further explore the possible association between HBM-causing LRP5 mutations and circulating serotonin, levels of the hormone were measured in the platelet poor plasma (PPP), serum, and platelet pellet (PP) of 16 affected individuals from 2 kindreds with HBM-causing LRP5 mutations (G171V and N198S) and 16 age-matched controls. When analyzed by HPLC, there were no differences in levels of serotonin in PPP and PP between affected individuals and age-matched controls. Similarly, when analyzed by ELISA, there were no differences in PPP or PP between these two groups. By ELISA, serum levels of serotonin were higher in the affected individuals when compared to age-matched controls. A subgroup analysis of only the G171V subjects (n=14) demonstrated that there were no differences in PPP and PP serotonin between affected individuals and controls when analyzed by HPLC. PP serotonin was lower in the affected individuals when measured by ELISA but serum serotonin levels were not different. We conclude that there is no change in PPP serotonin in individuals with HBM-causing mutations in LRP5.
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Affiliation(s)
- Grace S Lee
- Yale University School of Medicine, New Haven, CT, USA
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Schwarz P, Jørgensen NR, Abrahamsen B. Status of drug development for the prevention and treatment of osteoporosis. Expert Opin Drug Discov 2014; 9:245-53. [DOI: 10.1517/17460441.2014.884067] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Peter Schwarz
- Copenhagen University Hospital, Research Centre of Ageing and Osteoporosis, Department of Medicine, Glostrup, Denmark
- University of Copenhagen, Faculty of Health Sciences, Glostrup, Denmark
- Copenhagen University Hospital, Departments of Medicine, 2600 Glostrup, Denmark
| | - Niklas Rye Jørgensen
- Copenhagen University Hospital, Research Centre of Ageing and Osteoporosis, Department of Diagnostics, Glostrup, Denmark
- University of Copenhagen, Faculty of Health Sciences, Glostrup, Denmark
| | - Bo Abrahamsen
- Copenhagen University Hospital, Research Centre of Ageing and Osteoporosis, Department of Medicine, Glostrup, Denmark
- University of Southern Denmark, Glostrup, Denmark
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Shim JW, Dodge TR, Hammond MA, Wallace JM, Zhou FC, Yokota H. Physical weight loading induces expression of tryptophan hydroxylase 2 in the brain stem. PLoS One 2014; 9:e85095. [PMID: 24416346 PMCID: PMC3885668 DOI: 10.1371/journal.pone.0085095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 11/22/2013] [Indexed: 12/25/2022] Open
Abstract
Sustaining brain serotonin is essential in mental health. Physical activities can attenuate mental problems by enhancing serotonin signaling. However, such activity is not always possible in disabled individuals or patients with dementia. Knee loading, a form of physical activity, has been found to mimic effects of voluntary exercise. Focusing on serotonergic signaling, we addressed a question: Does local mechanical loading to the skeleton elevate expression of tryptophan hydroxylase 2 (tph2) that is a rate-limiting enzyme for brain serotonin? A 5 min knee loading was applied to mice using 1 N force at 5 Hz for 1,500 cycles. A 5-min treadmill running was used as an exercise (positive) control, and a 90-min tail suspension was used as a stress (negative) control. Expression of tph2 was determined 30 min – 2 h in three brain regions ––frontal cortex (FC), ventromedial hypothalamus (VMH), and brain stem (BS). We demonstrated for the first time that knee loading and treadmill exercise upregulated the mRNA level of tph2 in the BS, while tail suspension downregulated it. The protein level of tph2 in the BS was also upregulated by knee loading and downregulated by tail suspension. Furthermore, the downregulation of tph2 mRNA by tail suspension can be partially suppressed by pre-application of knee loading. The expression of tph2 in the FC and VMH was not significantly altered with knee loading. In this study we provided evidence that peripheral mechanical loading can activate central tph2 expression, suggesting that physical cues may mediate tph2-cathalyzed serotonergic signaling in the brain.
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Affiliation(s)
- Joon W. Shim
- Department of Biomedical Engineering, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana, United States of America
- * E-mail: (JWS) (JS); (HY) (HY)
| | - Todd R. Dodge
- Department of Biomedical Engineering, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana, United States of America
| | - Max A. Hammond
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, United States of America
| | - Joseph M. Wallace
- Department of Biomedical Engineering, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana, United States of America
- Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Feng C. Zhou
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Hiroki Yokota
- Department of Biomedical Engineering, Indiana University - Purdue University Indianapolis, Indianapolis, Indiana, United States of America
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail: (JWS) (JS); (HY) (HY)
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Galli C, Macaluso G, Passeri G. Serotonin: a novel bone mass controller may have implications for alveolar bone. J Negat Results Biomed 2013; 12:12. [PMID: 23964727 PMCID: PMC3766083 DOI: 10.1186/1477-5751-12-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 04/23/2013] [Indexed: 12/21/2022] Open
Abstract
As recent studies highlight the importance of alternative mechanisms in the control of bone turnover, new therapeutic approaches can be envisaged for bone diseases and periodontitis-induced bone loss. Recently, it has been shown that Fluoxetine and Venlafaxine, serotonin re-uptake inhibitors commonly used as antidepressants, can positively or negatively affect bone loss in rat models of induced periodontitis. Serotonin is a neurotransmitter that can be found within specific nuclei of the central nervous system, but can also be produced in the gut and be sequestered inside platelet granules. Although it is known to be mainly involved in the control of mood, sleep, and intestinal physiology, recent evidence has pointed at far reaching effects on bone metabolism, as a mediator of the effects of Lrp5, a membrane receptor commonly associated with Wnt canonical signaling and osteoblast differentiation. Deletion of Lrp5 in mice lead to increased expression of Tryptophan Hydroxylase 1, the gut isoform of the enzyme required for serotonin synthesis, thus increasing serum levels of serotonin. Serotonin, in turn, could bind to HTR1B receptors on osteoblasts and stop their proliferation by activating PKA and CREB. Although different groups have reported controversial results on the existence of an Lrp5-serotonin axis and the action of serotonin in bone remodeling, there is convincing evidence that serotonin modulators such as SSRIs can affect bone turnover. Consequently, the effects of this drug family on periodontal physiology should be thoroughly explored.
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Affiliation(s)
- Carlo Galli
- Dep, Biomedicine, Biotechnology and Translational Sciences, University of Parma, Via Gramsci 14, Parma 43126, Italy.
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Walsh JS, Newell-Price JD, DeBono M, Adaway J, Keevil B, Eastell R. Circulating serotonin and bone density, structure, and turnover in carcinoid syndrome. J Clin Endocrinol Metab 2013; 98:2902-7. [PMID: 23633214 PMCID: PMC3701278 DOI: 10.1210/jc.2012-4174] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Gut-derived serotonin has been proposed as a regulator of bone formation, and inhibition of gut serotonin synthesis increases bone formation in rodents. Carcinoid neuroendocrine tumors can produce very high levels of circulating serotonin and so offer a model of serotonin excess in humans. OBJECTIVES The objective of the study was to determine whether patients with carcinoid syndrome have lower bone formation markers, lower bone density, or poor bone structure compared with healthy controls. DESIGN We conducted a cross-sectional study of 25 patients with carcinoid syndrome and 25 healthy controls, individually matched to carcinoid patients by gender, age, height, and body mass index. OUTCOME MEASURES We measured circulating serotonin in blood and plasma and 5-hydroxyindoleacetic acid (5HIAA) in plasma and urine. We measured lumbar spine and hip bone mineral density by dual-energy x-ray absorptiometry, the distal radius and tibia with high-resolution peripheral quantitative computed tomography, and bone turnover with serum osteocalcin, amino-terminal propeptide of type I procollagen (PINP) and C-terminal telopeptide of type I collagen (CTX). RESULTS All measures of serotonin and 5HIAA were higher in carcinoid patients than in controls. No measures of bone density or bone structure differed significantly between cases and controls. Osteocalcin was higher in the cases than controls (26.0 vs 21.1 ng/mL, P = .02). PINP and CTX did not differ between cases and controls. In patients with carcinoid syndrome, plasma 5HIAA was positively correlated with osteocalcin. In controls, whole-blood serotonin was positively correlated with osteocalcin, PINP, and CTX (R values = 0.40-0.47, all P < .05.). CONCLUSIONS High circulating serotonin in carcinoid syndrome is not associated with clinically significant lower bone density, poorer bone structure, or lower bone formation markers.
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Affiliation(s)
- Jennifer S Walsh
- Academic Unit of Bone Metabolism, University of Sheffield and Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield S5 7AU, United Kingdom.
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Molecular dynamics simulation of tryptophan hydroxylase-1: binding modes and free energy analysis to phenylalanine derivative inhibitors. Int J Mol Sci 2013; 14:9947-62. [PMID: 23665899 PMCID: PMC3676822 DOI: 10.3390/ijms14059947] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 04/27/2013] [Accepted: 05/06/2013] [Indexed: 02/05/2023] Open
Abstract
Serotonin is a neurotransmitter that modulates many central and peripheral functions. Tryptophan hydroxylase-1 (TPH1) is a key enzyme of serotonin synthesis. In the current study, the interaction mechanism of phenylalanine derivative TPH1 inhibitors was investigated using molecular dynamics (MD) simulations, free energy calculations, free energy decomposition analysis and computational alanine scanning. The predicted binding free energies of these complexes are consistent with the experimental data. The analysis of the individual energy terms indicates that although the van der Waals and electrostatics interaction contributions are important in distinguishing the binding affinities of these inhibitors, the electrostatic contribution plays a more crucial role in that. Moreover, it is observed that different configurations of the naphthalene substituent could form different binding patterns with protein, yet lead to similar inhibitory potency. The combination of different molecular modeling techniques is an efficient way to interpret the interaction mechanism of inhibitors and our work could provide valuable information for the TPH1 inhibitor design in the future.
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Ortuño MJ, Ducy P. How understanding gut serotonin secretion could potentially lead to new treatments for osteoporosis. Expert Rev Endocrinol Metab 2013; 8:93-95. [PMID: 30736168 DOI: 10.1586/eem.12.80] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- María José Ortuño
- a Department of Genetics & Development. Columbia University Medical Center, New York, NY 10032, USA.
| | - Patricia Ducy
- b Department of Pathology & Cell Biology, Columbia University Medical Center, New York, NY 10032, USA
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Abstract
Skeletal health is dependent on the balance between bone resorption and formation during bone remodeling. Multiple signaling pathways play essential roles in the maintenance of skeletal integrity by positively or negatively regulating bone cells. During the last years, significant advances have been made in our understanding of the essential signaling pathways that regulate bone cell commitment, differentiation and survival. New signaling anabolic pathways triggered by parathyroid hormone, local growth factors, Wnt signaling, and calcium sensing receptor have been identified. Novel signals induced by interactions between bone cells-matrix (integrins), osteoblasts/osteocytes (cadherins, connexins), and osteoblasts/osteoclast (ephrins, Wnt-RhoA, semaphorins) have been discovered. Recent studies revealed the key pathways (MAPK, PI3K/Akt) that critically control bone cells and skeletal mass. This review summarizes the most recent knowledge on the major signaling pathways that control bone cells, and their potential impact on the development of therapeutic strategies to improve human bone health.
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Affiliation(s)
- Pierre J Marie
- Laboratory of osteoblast biology and pathology, INSERM, UMR-606, University Paris Diderot, Sorbonne Paris Cité, Hopital Lariboisiere, 2 rue Ambroise Pare, 75475 Paris cedex 10, France.
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Sjögren K, Engdahl C, Henning P, Lerner UH, Tremaroli V, Lagerquist MK, Bäckhed F, Ohlsson C. The gut microbiota regulates bone mass in mice. J Bone Miner Res 2012; 27:1357-67. [PMID: 22407806 PMCID: PMC3415623 DOI: 10.1002/jbmr.1588] [Citation(s) in RCA: 496] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The gut microbiota modulates host metabolism and development of immune status. Here we show that the gut microbiota is also a major regulator of bone mass in mice. Germ-free (GF) mice exhibit increased bone mass associated with reduced number of osteoclasts per bone surface compared with conventionally raised (CONV-R) mice. Colonization of GF mice with a normal gut microbiota normalizes bone mass. Furthermore, GF mice have decreased frequency of CD4(+) T cells and CD11b(+) /GR 1 osteoclast precursor cells in bone marrow, which could be normalized by colonization. GF mice exhibited reduced expression of inflammatory cytokines in bone and bone marrow compared with CONV-R mice. In summary, the gut microbiota regulates bone mass in mice, and we provide evidence for a mechanism involving altered immune status in bone and thereby affected osteoclast-mediated bone resorption. Further studies are required to evaluate the gut microbiota as a novel therapeutic target for osteoporosis.
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Affiliation(s)
- Klara Sjögren
- Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
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Chen GL, Miller GM. Advances in tryptophan hydroxylase-2 gene expression regulation: new insights into serotonin-stress interaction and clinical implications. Am J Med Genet B Neuropsychiatr Genet 2012; 159B:152-71. [PMID: 22241550 PMCID: PMC3587664 DOI: 10.1002/ajmg.b.32023] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Serotonin (5-HT) modulates the stress response by interacting with the hormonal hypothalamic-pituitary-adrenal (HPA) axis and neuronal sympathetic nervous system (SNS). Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in 5-HT biosynthesis, and the recent identification of a second, neuron-specific TPH isoform (TPH2) opened up a new area of research. While TPH2 genetic variance has been linked to numerous behavioral traits and disorders, findings on TPH2 gene expression have not only reinforced, but also provided new insights into, the long-recognized but not yet fully understood 5-HT-stress interaction. In this review, we summarize advances in TPH2 expression regulation and its relevance to the stress response and clinical implications. Particularly, based on findings on rhesus monkey TPH2 genetics and other relevant literature, we propose that: (i) upon activation of adrenal cortisol secretion, the cortisol surge induces TPH2 expression and de novo 5-HT synthesis; (ii) the induced 5-HT in turn inhibits cortisol secretion by modulating the adrenal sensitivity to ACTH via the suprachiasmatic nuclei (SCN)-SNS-adrenal system, such that it contributes to the feedback inhibition of cortisol production; (iii) basal TPH2 expression or 5-HT synthesis, as well as early-life experience, influence basal cortisol primarily via the hormonal HPA axis; and (iv) 5'- and 3'-regulatory polymorphisms of TPH2 may differentially influence the stress response, presumably due to their differential roles in gene expression regulation. Our increasing knowledge of TPH2 expression regulation not only helps us better understand the 5-HT-stress interaction and the pathophysiology of neuropsychiatric disorders, but also provides new strategies for the treatment of stress-associated diseases.
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Affiliation(s)
- Guo-Lin Chen
- Harvard Medical School, New England Primate Research Center, Division of Neuroscience, Southborough, MA 01772-9102, USA.
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Zhang W, Drake MT. Potential role for therapies targeting DKK1, LRP5, and serotonin in the treatment of osteoporosis. Curr Osteoporos Rep 2012; 10:93-100. [PMID: 22210558 DOI: 10.1007/s11914-011-0086-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Osteoporosis is a common disorder in which diminished bone mass leads to progressive microarchitectural skeletal deterioration and increased fracture risk. Our understanding of both normal and pathologic bone biology continues to evolve, and with it our grasp of the highly coordinated relationships between primary bone cells (osteoblasts, osteoclasts, and osteocytes) and the complex molecular signals bone cells use to integrate signals derived from other organ systems, including the immune, hematopoietic, gastrointestinal, and central nervous systems. It is now clear that the Wnt signaling pathway is central to regulation of both skeletal modeling and remodeling. Herein, we discuss components of the Wnt signaling pathway (DKK1, an endogenous soluble inhibitor of Wnt signaling) and LRP5 (a plasma membrane-localized Wnt co-receptor) as potential future targets for osteoporosis therapy. Finally, we discuss the current controversial role for serotonin in skeletal metabolism, and the potential role of future therapies targeting serotonin for osteoporosis treatment.
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Affiliation(s)
- Wei Zhang
- Division of Endocrinology, Department of Medicine, College of Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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