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Yu X, Tao J, Wu Y, Chen Y, Li P, Yang F, Tang M, Sammad A, Tao Y, Xu Y, Li YX. Deficiency of ASGR1 Alleviates Diet-Induced Systemic Insulin Resistance via Improved Hepatic Insulin Sensitivity. Diabetes Metab J 2024; 48:802-815. [PMID: 38310881 PMCID: PMC11307118 DOI: 10.4093/dmj.2023.0124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 09/06/2023] [Indexed: 02/06/2024] Open
Abstract
BACKGRUOUND Insulin resistance (IR) is the key pathological basis of many metabolic disorders. Lack of asialoglycoprotein receptor 1 (ASGR1) decreased the serum lipid levels and reduced the risk of coronary artery disease. However, whether ASGR1 also participates in the regulatory network of insulin sensitivity and glucose metabolism remains unknown. METHODS The constructed ASGR1 knockout mice and ASGR1-/- HepG2 cell lines were used to establish the animal model of metabolic syndrome and the IR cell model by high-fat diet (HFD) or drug induction, respectively. Then we evaluated the glucose metabolism and insulin signaling in vivo and in vitro. RESULTS ASGR1 deficiency ameliorated systemic IR in mice fed with HFD, evidenced by improved insulin intolerance, serum insulin, and homeostasis model assessment of IR index, mainly contributed from increased insulin signaling in the liver, but not in muscle or adipose tissues. Meanwhile, the insulin signal transduction was significantly enhanced in ASGR1-/- HepG2 cells. By transcriptome analyses and comparison, those differentially expressed genes between ASGR1 null and wild type were enriched in the insulin signal pathway, particularly in phosphoinositide 3-kinase-AKT signaling. Notably, ASGR1 deficiency significantly reduced hepatic gluconeogenesis and glycogenolysis. CONCLUSION The ASGR1 deficiency was consequentially linked with improved hepatic insulin sensitivity under metabolic stress, hepatic IR was the core factor of systemic IR, and overcoming hepatic IR significantly relieved the systemic IR. It suggests that ASGR1 is a potential intervention target for improving systemic IR in metabolic disorders.
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Affiliation(s)
- Xiaorui Yu
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Jiawang Tao
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yuhang Wu
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yan Chen
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Penghui Li
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fan Yang
- Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China
| | - Miaoxiu Tang
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Abdul Sammad
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yu Tao
- Laboratory of Biomaterials and Translational Medicine Center for Nanomedicine, The Third Affiliated Hospital, Guangzhou, China
| | - Yingying Xu
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, China
- Center for Health Research, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Science, Guangzhou, China
- State Key Laboratory of Respiratory Disease, Guangzhou, China
- China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, China
| | - Yin-Xiong Li
- Center for Health Research, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, China
- Center for Health Research, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Science, Guangzhou, China
- State Key Laboratory of Respiratory Disease, Guangzhou, China
- China-New Zealand Joint Laboratory on Biomedicine and Health, Guangzhou, China
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2
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Fernández-Rojas B, Gómez-Sierra T, Medina-Campos O, Hernández-Juárez J, Hernández-Cruz P, Gallegos-Velasco I, Pérez-Cervera Y, Pedraza-Chaverri J. Antioxidant activity of glucosamine and its effects on ROS production, Nrf2, and O-GlcNAc expression in HMEC-1 cells. Curr Res Toxicol 2023; 5:100128. [PMID: 37808439 PMCID: PMC10558709 DOI: 10.1016/j.crtox.2023.100128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 09/15/2023] [Accepted: 09/20/2023] [Indexed: 10/10/2023] Open
Abstract
Glucosamine (GlcN) is the most used supplement for osteoarthritis treatment. In vitro studies have related GlcN to beneficial and detrimental effects on health. The aim of this study was to evaluate the effects of O-linked-N-acetylglucosaminylation (O-GlcNAc) on GlcN-induced ROS production and Nrf2 expression in human dermal microvascular endothelial cells-1 (HMEC-1) and to evaluate the antioxidant capacity of GlcN compared to well-known antioxidants. For this, we evaluate the antioxidant capacity by in vitro assays. Besides, the GlcN (5-20 mM) effects on cell viability, reactive oxygen species (ROS) production, O-GlcNAc, and nuclear factor erythroid-2-related factor 2 (Nrf2) expression with and without the O-GlcNAc inhibitor OSMI-1 (10 μM) in HMEC-1 were evaluated. GlcN showed high inhibitory concentration (low scavenging activity) against superoxide (O2•─, IC20 = 47.67 mM), 2,2-diphenyl-1-picrylhydrazyl (DPPH•, IC50 = 21.32 mM), and hydroxyl (HO•, IC50 = 14.04 mM) radicals without scavenging activity against hydrogen peroxide (H2O2) and low antioxidant capacity determined by oxygen radical absorbance capacity (ORAC, 0.001 mM Trolox equivalent) and ferric reducing antioxidant power (FRAP, 0.046 mM Trolox equivalent). In cell culture, GlcN (20 mM) reduced cell viability up to 26 % and induced an increase in ROS production (up to 70 %), O-GlcNAc (4-fold-higher vs. control), and Nrf2 expression (56 %), which were prevented by OSMI-1. These data suggest an association between O-GlcNAc, ROS production, and Nrf2 expression in HMEC-1 cells stimulated with GlcN.
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Affiliation(s)
- B. Fernández-Rojas
- Laboratorio de Genómica, Proteómica y Glicobiología del Centro de Investigación, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca-Universidad Nacional Autónoma de México, Ex-Hacienda de Aguilera S/N, San Felipe del Agua, C.P. 68020, Oaxaca de Juárez, Oaxaca, México
| | - T. Gómez-Sierra
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, C.P. 04510, CDMX, México
| | - O.N. Medina-Campos
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, C.P. 04510, CDMX, México
| | - J. Hernández-Juárez
- CONAHCYT-Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Oaxaca, Instituto Politécnico Nacional, Calle Hornos 1003, C.P. 71230, Santa Cruz Xoxocotlán, Oaxaca, México
| | - P.A. Hernández-Cruz
- Laboratorio de Genómica, Proteómica y Glicobiología del Centro de Investigación, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca-Universidad Nacional Autónoma de México, Ex-Hacienda de Aguilera S/N, San Felipe del Agua, C.P. 68020, Oaxaca de Juárez, Oaxaca, México
| | - I.B. Gallegos-Velasco
- Laboratorio de Genómica, Proteómica y Glicobiología del Centro de Investigación, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca-Universidad Nacional Autónoma de México, Ex-Hacienda de Aguilera S/N, San Felipe del Agua, C.P. 68020, Oaxaca de Juárez, Oaxaca, México
| | - Y. Pérez-Cervera
- Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Avenida Universidad S/N, C.P. 68120, Oaxaca de Juárez, Oaxaca, México
| | - J. Pedraza-Chaverri
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, C.P. 04510, CDMX, México
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3
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Chen Y, Hu W, Li Q, Zhao S, Zhao D, Zhang S, Wei Z, Yang X, Chen Y, Li X, Liao C, Han J, Miao QR, Duan Y. NGBR is required to ameliorate type 2 diabetes in mice by enhancing insulin sensitivity. J Biol Chem 2021; 296:100624. [PMID: 33812996 PMCID: PMC8111265 DOI: 10.1016/j.jbc.2021.100624] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/11/2021] [Accepted: 03/31/2021] [Indexed: 02/07/2023] Open
Abstract
The reduction of insulin resistance or improvement of insulin sensitivity is the most effective treatment for type 2 diabetes (T2D). We previously reported that Nogo-B receptor (NGBR), encoded by the NUS1 gene, is required for attenuating hepatic lipogenesis by blocking nuclear translocation of liver X receptor alpha, suggesting its important role in regulating hepatic lipid metabolism. Herein, we demonstrate that NGBR expression was decreased in the liver of obesity-associated T2D patients and db/db mice. NGBR knockout in mouse hepatocytes resulted in increased blood glucose, insulin resistance, and beta-cell loss. High-fat diet (HFD)/streptozotocin (STZ)-treated mice presented the T2D phenotype by showing increased nonesterified fatty acid (NEFA) and triglyceride (TG) in the liver and plasma and increased insulin resistance and beta-cell loss. AAV-mediated NGBR overexpression in the liver reduced NEFA and TG in the liver and circulation and improved liver functions. Consequently, HFD/STZ-treated mice with hepatic NGBR overexpression had increased insulin sensitivity and reduced beta-cell loss. Mechanistically, NGBR overexpression restored insulin signaling of AMPKα1-dependent phosphorylation of AKT and GSK3β. NGBR overexpression also reduced expression of endoplasmic reticulum stress-associated genes in the liver and skeletal muscle to improve insulin sensitivity. Together, our results reveal that NGBR is required to ameliorate T2D in mice, providing new insight into the role of hepatic NGBR in insulin sensitivity and T2D treatment.
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Affiliation(s)
- Yi Chen
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China; Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Wenquan Hu
- Children's Research Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, USA; Diabetes and Obesity Research Center, New York University Long Island School of Medicine, Mineola, New York, USA
| | - Qi Li
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Shiwei Zhao
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Dan Zhao
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Shuang Zhang
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Zhuo Wei
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Xiaoxiao Yang
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Yuanli Chen
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Xiaoju Li
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Chenzhong Liao
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Jihong Han
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China; Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Qing Robert Miao
- Children's Research Institute, Medical College of Wisconsin, Milwaukee, Wisconsin, USA; Diabetes and Obesity Research Center, New York University Long Island School of Medicine, Mineola, New York, USA.
| | - Yajun Duan
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China.
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Yan T, Nian T, Li F, He B, Jia Y, Bi K, Wang Z. Salidroside from Rhodiola wallichiana var. cholaensis reverses insulin resistance and stimulates the GLP-1 secretion by alleviating ROS-mediated activation of MAPKs signaling pathway and mitigating apoptosis. J Food Biochem 2020; 44:e13446. [PMID: 32910486 DOI: 10.1111/jfbc.13446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 12/20/2022]
Abstract
The present study was aimed to investigate the mechanisms of salidroside (SAL) from Rhodiola wallichiana var. cholaensis on hypoglycemic and oxidative stress responses. The palmitate (PA)-induced GLUTag cells model and the glucosamine-induced insulin resistance model in HepG2 cells were built. SAL led to the up-regulation of the serum glucagon-like peptide 1 (GLP-1) level by facilitating the SCFAs production, the promotion of GLP-1 synthesis by improving p38 MAPK phosphorylation and regulating insulin resistance. Moreover, the production of reactive oxygen species (ROS) and the expression of MAPKs were down-regulated. Furthermore, SAL was found to be able to inhibit PA-induced apoptosis that down-regulates cleaved caspase-3 and Bax expressions, while up-regulating Bcl-2 expression and up-regulates the Bcl-2/Bax ratio in glucosamine induced insulin resistance model. Besides, SAL can also up-regulate the mTOR/p70S6k signaling pathway in the PA-induced GLUTag cells model. Our data demonstrated that SAL could reverse insulin resistance and stimulates the GLP-1 secretion by alleviating ROS-mediated activation of MAPKs signaling pathway and mitigating apoptosis. PRACTICAL APPLICATIONS: Our data showed that SAL could increase the GLP-1 level by stimulating the SCFAs production and p38 phosphorylation and facilitate the IR and GLP-1 synthesis by alleviating ROS-mediated activation of MAPKs signaling pathway and mitigating apoptosis. Furthermore, the SAL has also stimulated the mTOR/p70S6k signaling pathway in PA-induced GLUTag cells model. The results provided a possibility to employ SAL for diabetes treatment.
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Affiliation(s)
- Tingxu Yan
- Jiangsu Kangyuan Pharmaceutical Co., Ltd, Lianyungang, China.,School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, China
| | - Tingting Nian
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China
| | - Fuyuan Li
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China
| | - Bosai He
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, China
| | - Ying Jia
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, China
| | - Kaishun Bi
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Zhenzhong Wang
- Jiangsu Kangyuan Pharmaceutical Co., Ltd, Lianyungang, China.,State Key Laboratory of New-Tech for Chinese Medicine Pharmaceutical Process, Jiangsu Kanion Pharmaceutical Co. Ltd, Lianyungang, China
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5
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Hill JW, Elias CF. Neuroanatomical Framework of the Metabolic Control of Reproduction. Physiol Rev 2019; 98:2349-2380. [PMID: 30109817 DOI: 10.1152/physrev.00033.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A minimum amount of energy is required for basic physiological processes, such as protein biosynthesis, thermoregulation, locomotion, cardiovascular function, and digestion. However, for reproductive function and survival of the species, extra energy stores are necessary. Production of sex hormones and gametes, pubertal development, pregnancy, lactation, and parental care all require energy reserves. Thus the physiological systems that control energy homeostasis and reproductive function coevolved in mammals to support both individual health and species subsistence. In this review, we aim to gather scientific knowledge produced by laboratories around the world on the role of the brain in integrating metabolism and reproduction. We describe essential neuronal networks, highlighting key nodes and potential downstream targets. Novel animal models and genetic tools have produced substantial advances, but critical gaps remain. In times of soaring worldwide obesity and metabolic dysfunction, understanding the mechanisms by which metabolic stress alters reproductive physiology has become crucial for human health.
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Affiliation(s)
- Jennifer W Hill
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
| | - Carol F Elias
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
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Zhu D, Wang Y, Du Q, Liu Z, Liu X. Cichoric Acid Reverses Insulin Resistance and Suppresses Inflammatory Responses in the Glucosamine-Induced HepG2 Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:10903-10913. [PMID: 26592089 DOI: 10.1021/acs.jafc.5b04533] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cichoric acid, a caffeic acid derivative found in Echinacea purpurea, basil, and chicory, has been reported to have bioactive effects, such as anti-inflammatory, antioxidant, and preventing insulin resistance. In this study, to explore the effects of CA on regulating insulin resistance and chronic inflammatory responses, the insulin resistance model was constructed by glucosamine in HepG2 cells. CA stimulated glucosamine-mediated glucose uptake by stimulating translocation of the glucose transporter 2. Moreover, the production of reactive oxygen, the expression of COX-2 and iNOS, and the mRNA levels of TNF-α and IL-6 were attenuated. Furthermore, CA was verified to promote glucosamine-mediated glucose uptake and inhibited inflammation through PI3K/Akt, NF-κB, and MAPK signaling pathways in HepG2 cells. These results implied that CA could increase glucose uptake, improve insulin resistance, and attenuate glucosamine-induced inflammation, suggesting that CA is a potential natural nutraceutical with antidiabetic properties and anti-inflammatory effects.
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Affiliation(s)
- Di Zhu
- College of Food Science and Engineering, Northwest A&F University , Yangling 712100, China
| | - Yutang Wang
- College of Food Science and Engineering, Northwest A&F University , Yangling 712100, China
| | - Qingwei Du
- Functional Food Engineering and Technology Research Center of Shaanxi Province , Xi'an 710054, China
| | - Zhigang Liu
- College of Food Science and Engineering, Northwest A&F University , Yangling 712100, China
| | - Xuebo Liu
- College of Food Science and Engineering, Northwest A&F University , Yangling 712100, China
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Wang DF, Yang HJ, Gu JQ, Cao YL, Meng X, Wang XL, Lin YC, Gao M. Suppression of phosphatase and tensin homolog protects insulin-resistant cells from apoptosis. Mol Med Rep 2015; 12:2695-700. [PMID: 25962562 DOI: 10.3892/mmr.2015.3771] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 12/12/2014] [Indexed: 11/06/2022] Open
Abstract
In the present study, a glucosamine-induced model of insulin-resistant skeletal muscle cells was established in order to investigate the effect of inhibition of phosphatase and tensin homolog (PTEN)/5'-adenosine monophosphate-activated protein kinase (AMPK) on these cells. The glucosamine-induced insulin-resistant skeletal muscle cells were produced and the rate of glucose uptake was measured using the glucose oxidase-peroxidase method. The expression levels of PTEN and phosphorylated PTEN (p-PTEN) were assessed using western blotting. Glucose transporter 4 (GLUT4) translocation was detected by immunofluorescence. Cell apoptosis was evaluated using flow cytometry. Following insulin stimulation, the rate of glucose uptake was significantly reduced in the cells with glucosamine-induced insulin-resistance in comparison with those in the control group. The expression and translocation of GLUT4 were reduced in the insulin-resistant muscle cells. By contrast, the expression of PTEN and p-PTEN as well as apoptosis were significantly increased. Following treatment with bisperoxopicolinatooxovanadate (BPV) or metformin in the insulin-resistant skeletal muscle cells, there was an increase in the rate of glucose uptake, an increase in GLUT4 expression and its translocation, a reduction in the expression of PTEN and p-PTEN, and a decrease in cell apoptosis compared with untreated insulin-resistant cells. Glucosamine may be used to produce an effective model of insulin-resistant skeletal muscle cells. Cells with glucosamine-induced insulin-resistance exhibited a reduced expression of GLUT4 and dysfunction in GLUT4 translocation, as well as increased activation of PTEN and increased cell apoptosis. Inhibition of PTEN or its upstream regulator, AMPK, protects glucosamine-induced insulin-resistant skeletal muscle cells from apoptosis.
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Affiliation(s)
- Di-Fei Wang
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Hui-Jing Yang
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Jian-Qiu Gu
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Yan-Li Cao
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Xin Meng
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Xiao-Li Wang
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Yi-Chen Lin
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Ming Gao
- Department of Geriatric Endocrinology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
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8
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Specific insulin/IGF1 hybrid receptor activation assay reveals IGF1 as a more potent ligand than insulin. Sci Rep 2015; 5:7911. [PMID: 25604425 PMCID: PMC4300458 DOI: 10.1038/srep07911] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/19/2014] [Indexed: 12/15/2022] Open
Abstract
This novel method enables specific measurement of the activation of hybrid receptors formed between the Insulin Receptor (IR) and the Insulin-like Growth Factor 1 Receptor (IGF1R). These hybrid receptors are present in tissues and cell lines expressing both IR and IGF1R. It is therefore challenging to separate the homodimer and hybrid receptor activation properties. This ELISA method enabled fast and quantitative measurements of activated hybrid receptors. The hybrid receptor specificity is obtained from a combination of two specific antibodies for IGF1R and for an IR tyrosine phosphorylation site. The specificity was shown by immunoprecipitations and Western blot analysis. IR exists as two splice variants; consequently, two splice variants of hybrid receptors can be expressed. It is reported here that both splice variants of insulin/IGF1 receptor hybrids are activated by IGF1 with >20-fold higher potency than insulin.
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Wolfe A, Divall S, Wu S. The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1). Front Neuroendocrinol 2014; 35:558-72. [PMID: 24929098 PMCID: PMC4175134 DOI: 10.1016/j.yfrne.2014.05.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 04/01/2014] [Accepted: 05/27/2014] [Indexed: 12/27/2022]
Abstract
The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction.
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Affiliation(s)
- Andrew Wolfe
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States.
| | - Sara Divall
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States
| | - Sheng Wu
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States
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10
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Zhou B, Zhang Y, Zhang F, Xia Y, Liu J, Huang R, Wang Y, Hu Y, Wu J, Dai C, Wang H, Tu Y, Peng X, Wang Y, Zhai Q. CLOCK/BMAL1 regulates circadian change of mouse hepatic insulin sensitivity by SIRT1. Hepatology 2014; 59:2196-206. [PMID: 24442997 DOI: 10.1002/hep.26992] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 12/23/2013] [Indexed: 12/27/2022]
Abstract
UNLABELLED The protein deacetylase, sirtuin 1 (SIRT1), involved in regulating hepatic insulin sensitivity, shows circadian oscillation and regulates the circadian clock. Recent studies show that circadian misalignment leads to insulin resistance (IR); however, the underlying mechanisms are largely unknown. Here, we show that CLOCK and brain and muscle ARNT-like protein 1 (BMAL1), two core circadian transcription factors, are correlated with hepatic insulin sensitivity. Knockdown of CLOCK or BMAL1 induces hepatic IR, whereas their ectopic expression attenuates hepatic IR. Moreover, circadian change of insulin sensitivity is impaired in Clock mutant, liver-specific Bmal1 knockout (KO) or Sirt1 KO mice, and CLOCK and BMAL1 are required for hepatic circadian expression of SIRT1. Further studies show that CLOCK/BMAL1 binds to the SIRT1 promoter to enhance its expression and regulates hepatic insulin sensitivity by SIRT1. In addition, constant darkness-induced circadian misalignment in mice decreases hepatic BMAL1 and SIRT1 levels and induces IR, which can be dramatically reversed by resveratrol. CONCLUSION These findings offer new insights for coordination of the circadian clock and metabolism in hepatocytes by circadian regulation of hepatic insulin sensitivity via CLOCK/BMAL1-dependent SIRT1 expression and provide a potential application of resveratrol for combating circadian misalignment-induced metabolic disorders.
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Affiliation(s)
- Ben Zhou
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate University of Chinese Academy of Sciences, Shanghai, China
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Yuasa T, Amo K, Ishikura S, Nagaya H, Uchiyama K, Hashida S, Ebina Y. Development of in vitro model of insulin receptor cleavage induced by high glucose in HepG2 cells. Biochem Biophys Res Commun 2014; 445:236-43. [PMID: 24508798 DOI: 10.1016/j.bbrc.2014.01.187] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 01/30/2014] [Indexed: 12/14/2022]
Abstract
Soluble insulin receptor (sIR), the ectodomain of IR, has been detected in human plasma, and its concentration parallels that of blood glucose in patients with diabetes. IR has a pivotal role in glucose homeostasis and diabetes development; therefore, cleavage of IR promoted by hyperglycemia is involved in insulin resistance and glucose toxicity. To elucidate the physiology of sIR, we developed an in vitro model mimicking the changes in sIR levels in plasma from patients with diabetes. Among four human cell lines that expressed IR, spontaneous cleavage of IR occurred only in HepG2 cells. The molecular characteristics of sIR derived from HepG2 cells were similar to those of sIR detected in human plasma. The concentration of sIR in the medium did not differ between basal and high-glucose conditions in the initial 24-h period, but increasing the duration of pre-stimulation (>48 h) led to a significant increase in sIR levels in cells exposed to high glucose. Additionally, glucose-dependent increment of sIR was reversible in this model. These results are consistent with the observation of plasma sIR in patients with diabetes. Using this model, O-linked N-acetylglucosamine modification was determined to be involved in high-glucose-induced IR cleavage. A calcium-dependent protease was shown to cleave IR extracellularly. These findings show that this in vitro model could be useful for determining the molecular mechanism underlying IR cleavage.
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Affiliation(s)
- Tomoyuki Yuasa
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan
| | - Kikuko Amo
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan
| | - Shuhei Ishikura
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan
| | - Hisao Nagaya
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan
| | - Keiji Uchiyama
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan
| | - Seiichi Hashida
- Institute for Health Sciences, Tokushima Bunri University, Tokushima 770-8514, Japan
| | - Yousuke Ebina
- Division of Molecular Genetics, Institute for Enzyme Research, Tokushima University, 3-18-15 Kuramotocho, Tokushima 770-8503, Japan.
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Xiao F, Huang Z, Li H, Yu J, Wang C, Chen S, Meng Q, Cheng Y, Gao X, Li J, Liu Y, Guo F. Leucine deprivation increases hepatic insulin sensitivity via GCN2/mTOR/S6K1 and AMPK pathways. Diabetes 2011; 60:746-56. [PMID: 21282364 PMCID: PMC3046835 DOI: 10.2337/db10-1246] [Citation(s) in RCA: 223] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE We have previously shown that serum insulin levels decrease threefold and blood glucose levels remain normal in mice fed a leucine-deficient diet, suggesting increased insulin sensitivity. The goal of the current study is to investigate this possibility and elucidate the underlying cellular mechanisms. RESEARCH DESIGN AND METHODS Changes in metabolic parameters and expression of genes and proteins involved in regulation of insulin sensitivity were analyzed in mice, human HepG2 cells, and mouse primary hepatocytes under leucine deprivation. RESULTS We show that leucine deprivation improves hepatic insulin sensitivity by sequentially activating general control nonderepressible (GCN)2 and decreasing mammalian target of rapamycin/S6K1 signaling. In addition, we show that activation of AMP-activated protein kinase also contributes to leucine deprivation-increased hepatic insulin sensitivity. Finally, we show that leucine deprivation improves insulin sensitivity under insulin-resistant conditions. CONCLUSIONS This study describes mechanisms underlying increased hepatic insulin sensitivity under leucine deprivation. Furthermore, we demonstrate a novel function for GCN2 in the regulation of insulin sensitivity. These observations provide a rationale for short-term dietary restriction of leucine for the treatment of insulin resistance and associated metabolic diseases.
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Affiliation(s)
- Fei Xiao
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Zhiying Huang
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Houkai Li
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Junjie Yu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Chunxia Wang
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Shanghai Chen
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Qingshu Meng
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Ying Cheng
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Xiang Gao
- Model Animal Research Center, Nanjing University, Nanjing, China
| | - Jia Li
- National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Yong Liu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
| | - Feifan Guo
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, the Graduate School of the Chinese Academy of Sciences, Shanghai, China
- Corresponding author: Feifan Guo,
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13
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Diabetes mellitus impairs the response to intra-arterial chemotherapy in hepatocellular carcinoma. Med Oncol 2010; 28:1080-8. [DOI: 10.1007/s12032-010-9650-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 08/03/2010] [Indexed: 12/15/2022]
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14
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Hashimoto R, Sakai K, Matsumoto H, Iwashita M. Tumor necrosis factor-alpha (TNF-alpha) inhibits insulin-like growth factor-I (IGF-I) activities in human trophoblast cell cultures through IGF-I/insulin hybrid receptors. Endocr J 2010; 57:193-200. [PMID: 20009360 DOI: 10.1507/endocrj.k09e-189] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Tumor necrosis factor-alpha (TNF-alpha) in placenta is believed to be involved in pathogenesis of intrauterine growth restriction. In contrast, insulin-like growth factors (IGFs) are believed to be important for stimulation of fetal and placental growth. IGF-I stimulates metabolic and growth-promoting actions directly through its receptors: IGF-I receptor (IGF-IR), insulin receptor (IR) and IGF-I/insulin hybrid receptor (HR). However, it has not been elucidated which receptor mediates the growth promoting effects in fetal and placental growth. The current studies were undertaken to test whether TNF-alpha affects IGF-I action on placenta using human trophoblast cell cultures, and to test which receptor mediates growth promoting effects of IGF-I in placenta. Primary culture of trophoblast cells, which express IGF-IR, IR, and HR, were exposed to TNF-alpha, and the effects of IGF-I in stimulating trophoblast cell proliferation and migration were determined. Exposure to TNF-alpha attenuated the effects of IGF-I on cell proliferation and migration. To determine which receptors are involved in this inhibitory effect, the ability of IGF-I to stimulate phosphorylation of its receptors was analyzed in the presence of TNF-alpha. TNF-alpha exposure neither attenuated the phosphorylation of IGF-IR homodimer by IGF-I nor changed receptor abundance. In contrast, TNF-alpha reduced the ability of IGF-I to stimulate phosphorylation of HR with reducing amounts of HR. Exposure to TNF-alpha also attenuated phosphorylation of insulin receptor substrate-1 (IRS-1) and the association of IRS-1 with phosphatydilinositol-3 kinase (PI-3 kinase). Taken together, these findings indicate that TNF-alpha induces a loss of sensitivity to stimulation by IGF-I, through reducing amounts of HR and the stimulation of HR tyrosine kinase activity by IGF-I.
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Affiliation(s)
- Reiko Hashimoto
- Department of Obstetrics and Gynecology, School of Medicine, Kyorin University, Tokyo, Japan
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15
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TNFalpha activation of PKCdelta, mediated by NFkappaB and ER stress, cross-talks with the insulin signaling cascade. Cell Signal 2009; 22:274-84. [PMID: 19782747 DOI: 10.1016/j.cellsig.2009.09.029] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Accepted: 09/14/2009] [Indexed: 02/06/2023]
Abstract
TNFalpha plays key roles in the regulation of inflammation, cell death, and proliferation and its signaling cascade cross-talks with the insulin signaling cascade. PKCdelta, a novel PKC isoform, is known to participate in proximal TNFalpha signaling events. However, it has remained unclear whether PKCdelta plays a role in distal TNFalpha signaling events. Here we demonstrate that PKCdelta is activated by TNFalpha in a delayed fashion that is temporally associated with JNK activation. To investigate the signaling pathways activating PKCdelta and JNK, we used pharmacological and genetic inhibitors of NFkappaB. We found that inhibition of NFkappaB attenuated PKCdelta and JNK activations. Further analysis revealed that ER stress contributes to TNFalpha-stimulated PKCdelta and JNK activations. To investigate the role of PKCdelta in TNFalpha action, we used 29-mer shRNAs to silence PKCdelta expression. A reduction of ~90% in PKCdelta protein levels reduced TNFalpha-stimulated stress kinase activation, including JNK. Further, PKCdelta was necessary for thapsigargin-stimulated JNK activation. Because thapsigargin is a potent inducer of ER stress, we determined whether PKCdelta was necessary for induction of the UPR. Indeed, a reduction in PKCdelta protein levels reduced thapsigargin-stimulated CHOP induction, a hallmark of the UPR, but not BiP/GRP78 induction, suggesting that PKCdelta does not globally regulate the UPR. Next, the role of PKCdelta in TNFalpha mediated cross-talk with the insulin signaling pathway was investigated in cells expressing human IRS-1 and a 29-mer shRNA to silence PKCdelta expression. We found that a reduction in PKCdelta protein levels reversed the TNFalpha-mediated reduction in insulin-stimulated IRS-1 Tyr phosphorylation, Akt activation, and glycogen synthesis. In addition, TNFalpha-stimulated IRS protein Ser/Thr phosphorylation and degradation were blocked. Our results indicate that: 1) NFkappaB and ER stress contribute in part to PKCdelta activation; 2) PKCdelta plays a key role in the propagation of the TNFalpha signal; and 3) PKCdelta contributes to TNFalpha-induced inhibition of insulin signaling events.
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16
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Breuhahn K, Schirmacher P. Reactivation of the insulin-like growth factor-II signaling pathway in human hepatocellular carcinoma. World J Gastroenterol 2008; 14:1690-8. [PMID: 18350600 PMCID: PMC2695909 DOI: 10.3748/wjg.14.1690] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Constitutive activation of the insulin-like growth factor (IGF)-signaling axis is frequently observed in human hepatocellular carcinoma (HCC). Especially the overexpression of the fetal growth factor IGF-II, IGF-Ireceptor (IGF-IR), and cytoplasmic downstream effectors such as insulin-receptor substrates (IRS) contribute to proliferation, anti-apoptosis, and invasive behavior. This review focuses on the relevant alterations in this signaling pathway and independent in vivo models that support the central role IGF-II signaling during HCC development and progression. Since this pathway has become the center of interest as a target for potential anti-cancer therapy in many types of malignancies, various experimental strategies have been developed, including neutralizing antibodies and selective receptor kinase inhibitors, with respect to the specific and efficient reduction of oncogenic IGF-II/IGF-IR-signaling.
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17
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Gouze JN, Gouze E, Popp MP, Bush ML, Dacanay EA, Kay JD, Levings PP, Patel KR, Saran JPS, Watson RS, Ghivizzani SC. Exogenous glucosamine globally protects chondrocytes from the arthritogenic effects of IL-1beta. Arthritis Res Ther 2007; 8:R173. [PMID: 17109745 PMCID: PMC1794517 DOI: 10.1186/ar2082] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2006] [Revised: 09/19/2006] [Accepted: 11/16/2006] [Indexed: 11/20/2022] Open
Abstract
The effects of exogenous glucosamine on the biology of articular chondrocytes were determined by examining global transcription patterns under normal culture conditions and following challenge with IL-1β. Chondrocytes isolated from the cartilage of rats were cultured in several flasks either alone or in the presence of 20 mM glucosamine. Six hours later, one-half of the cultures of each group were challenged with 10 ng/ml IL-1β. Fourteen hours after this challenge, RNA was extracted from each culture individually and used to probe microarray chips corresponding to the entire rat genome. Glucosamine alone had no observable stimulatory effect on the transcription of primary cartilage matrix genes, such as aggrecan, collagen type II, or genes involved in glycosaminoglycan synthesis; however, glucosamine proved to be a potent, broad-spectrum inhibitor of IL-1β. Of the 2,813 genes whose transcription was altered by IL-1β stimulation (P < 0.0001), glucosamine significantly blocked the response in 2,055 (~73%). Glucosamine fully protected the chondrocytes from IL-1-induced expression of inflammatory cytokines, chemokines, and growth factors as well as proteins involved in prostaglandin E2 and nitric oxide synthesis. It also blocked the IL-1-induced expression of matrix-specific proteases such as MMP-3, MMP-9, MMP-10, MMP-12, and ADAMTS-1. The concentrations of IL-1 and glucosamine used in these assays were supraphysiological and were not representative of the arthritic joint following oral consumption of glucosamine. They suggest, however, that the potential benefit of glucosamine in osteoarthritis is not related to cartilage matrix biosynthesis, but is more probably related to its ability to globally inhibit the deleterious effects of IL-1β signaling. These results suggest that glucosamine, if administered effectively, may indeed have anti-arthritic properties, but primarily as an anti-inflammatory agent.
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Affiliation(s)
- Jean-Noël Gouze
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Elvire Gouze
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Mick P Popp
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL 32610-0137, USA
| | - Marsha L Bush
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Emil A Dacanay
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Jesse D Kay
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Padraic P Levings
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Kunal R Patel
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Jeet-Paul S Saran
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Rachael S Watson
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
| | - Steven C Ghivizzani
- Department of Orthopaedics and Rehabilitation, Gene Therapy Laboratory, University of Florida, College of Medicine, PO Box 100137, Gainesville, FL 32610-0137, USA
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18
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Chisalita SI, Nitert MD, Arnqvist HJ. Characterisation of receptors for IGF-I and insulin; evidence for hybrid insulin/IGF-I receptor in human coronary artery endothelial cells. Growth Horm IGF Res 2006; 16:258-266. [PMID: 16914341 DOI: 10.1016/j.ghir.2006.06.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Accepted: 06/09/2006] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Coronary artery disease is a prevalent cause of morbidity and mortality in diabetes. Little is known about insulin-like growth factor-I receptors (IGF-IR) and insulin receptors (IR) in human coronary endothelium. Our aim was to characterize IGF-IR and IR in human coronary artery endothelial cells (HCAEC). DESIGN Cultured human coronary artery endothelial cells were used. Gene expression was measured by quantitative real-time RT-PCR analysis and receptor affinity by ligand binding. Receptor protein, phosphorylation of IGF-IR and IR beta-subunit as well as the presence of hybrid insulin receptor/Insulin-like growth factor-I receptor (Hybrid IR/IGF-IR) was analyzed by immunoprecipitation and Western blot. Postreceptor effects of insulin and IGF-I were assed by (3)H-thymidine incorporation. RESULTS The gene expression of IGF-IR was several folds higher than that of IR. and insulin receptor isoform A (IR-A) was 20-fold more expressed than insulin receptor isoform B (IR-B) in HCAEC. The specific binding of (125)I-IGF-I was higher than that of (125)I-insulin. Insulin and the new long acting insulin analog, glargine, interacted with the IGF-IR with over thousand and 100-fold less potency than IGF-I itself, whereas IGF-II had 6 times lower potency than IGF-I. Phosphorylation of the IGF-IR beta-subunit was obtained by concentrations of 10(-10)-10(-8)M IGF-I, 10(-6)M of insulin, inconsistently by 10(-8)M insulin and not at all by 10(-10)-10(-9)M insulin. The IR beta-subunit was phosphorylated by insulin and IGF-I at concentrations of 10(-9)-10(-8)M. When immunoprecipitating with specific monoclonal anti-IR or anti-IGF-IR alpha-subunit antibodies we found bands situated in slightly different positions suggesting the presence of Hybrid IR/IGF-IR. IGF-I, IGF-II and insulin (10(-9)-10(-7)M) had no significant effect on (3)H-thymidine incorporation into DNA. CONCLUSIONS Human coronary endothelial cells express more IGF-IR than IR, mainly IR-A, and also Hybrid IR/IGF-IR. Both IGF-I and insulin phosphorylate their receptors, but only IGF-I seems to phosphorylate Hybrid IR/IGF-IR. Our study provides experimental evidence for a possible role of IGF-IR, IR and Hybrid IR/IGF-IR in human coronary artery endothelial cells.
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Affiliation(s)
- Simona I Chisalita
- Diabetes Research Centre and Division of Cell Biology, Department of Biomedicine and Surgery, Faculty of Health Sciences, Linköping University, S-581 85 Linköping, Sweden
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19
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Scarth JP. Modulation of the growth hormone-insulin-like growth factor (GH-IGF) axis by pharmaceutical, nutraceutical and environmental xenobiotics: an emerging role for xenobiotic-metabolizing enzymes and the transcription factors regulating their expression. A review. Xenobiotica 2006; 36:119-218. [PMID: 16702112 DOI: 10.1080/00498250600621627] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The growth hormone-insulin-like growth factor (GH-IGF) axis has gained considerable focus over recent years. One cause of this increased interest is due to a correlation of age-related decline in plasma GH/IGF levels with age-related degenerative processes, and it has led to the prescribing of GH replacement therapy by some practitioners. On the other hand, however, research has also focused on the pro-carcinogenic effects of high GH-IGF levels, providing strong impetus for finding regimes that reduce its activity. Whereas the effects of GH/IGF activity on the action of xenobiotic-metabolizing enzyme systems is reasonably well appreciated, the effects of xenobiotic exposure on the GH-IGF axis has not received substantial review. Relevant xenobiotics are derived from pharmaceutical, nutraceutical and environmental exposure, and many of the mechanisms involved are highly complex in nature, not easily predictable from existing in vitro tests and do not always predict well from in vivo animal models. After a review of the human and animal in vivo and in vitro literature, a framework for considering the different levels of direct and indirect modulation by xenobiotics is developed herein, and areas that still require further investigation are highlighted, i.e. the actions of common endocrine disruptors such as pesticides and phytoestrogens, as well as the role of xenobiotic-metabolizing enzymes and the transcription factors regulating their expression. It is anticipated that a fuller appreciation of the existing human paradigms for GH-IGF axis modulation gained through this review may help explain some of the variation in levels of plasma IGF-1 and its binding proteins in the population, aid in the prescription of particular dietary regimens to certain individuals such as those with particular medical conditions, guide the direction of long-term drug/nutraceutical safety trials, and stimulate ideas for future research. It also serves to warn athletes that using compounds touted as performance enhancing because they promote short-term GH release could in fact be detrimental to performance in the long-run.
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Affiliation(s)
- J P Scarth
- The Horseracing Forensic Laboratories (HFL), Fordham, UK.
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20
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Breuhahn K, Longerich T, Schirmacher P. Dysregulation of growth factor signaling in human hepatocellular carcinoma. Oncogene 2006; 25:3787-800. [PMID: 16799620 DOI: 10.1038/sj.onc.1209556] [Citation(s) in RCA: 432] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Dysregulation of pleiotropic growth factors, receptors and their downstream signaling pathway components represent a central protumorigenic principle in human hepatocarcinogenesis. Especially the Insulin-like Growth Factor/IGF-1 receptor (IGF/IGF-1R), Hepatocyte Growth Factor (HGF/MET), Wingless (Wnt/beta-catenin/FZD), Transforming Growth Factor alpha/Epidermal Growth Factor receptor (TGFalpha/EGFR) and Transforming Growth Factor beta (TGFbeta/TbetaR) pathways contribute to proliferation, antiapoptosis and invasive behavior of tumor cells. This review focuses on the relevant alterations in these pathways identified in human human hepatocellular carcinomas (HCCs). Resultant functional effects are modulated by multiple cross-talks between the different signaling pathways and additional tumor-relevant factors, such as cyclooxygenase-2 and p53. Several specific strategies are currently under development such as receptor kinase inhibitors, neutralizing antibodies and antagonistic proteins, which may improve the systemic treatment of human HCCs.
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Affiliation(s)
- K Breuhahn
- Institute of Pathology, University of Heidelberg, Heidelberg, Germany
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21
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Raile K, Klammt J, Schneider A, Keller A, Laue S, Smith R, Pfäffle R, Kratzsch J, Keller E, Kiess W. Clinical and functional characteristics of the human Arg59Ter insulin-like growth factor i receptor (IGF1R) mutation: implications for a gene dosage effect of the human IGF1R. J Clin Endocrinol Metab 2006; 91:2264-71. [PMID: 16569742 DOI: 10.1210/jc.2005-2146] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Signaling via the IGF-I receptor (IGF-IR) is crucial for normal prenatal and postnatal growth. The heterozygous IGF-IR mutation Arg59Ter resulted in reduced IGF-IR expression and represents haploinsufficiency of the human IGF1R gene. OBJECTIVE We studied clinical and in vitro aspects of a human IGF1R gene dosage effect. We provide detailed clinical data on the two half-brothers and their mother with the Arg59Ter mutation. Arg59Ter and control fibroblasts were examined for functionality of IGF-I and insulin-stimulated receptor phosphorylation and signal transduction. RESULTS The two brothers presented with primary microcephaly, mild mental retardation, and intrauterine as well as postnatal growth deficits. After GH therapy (30 microg/kg.d) for 24 months, the growth deficit in the propositus decreased by +1.0 sd. There was no clinical evidence for impaired glucose tolerance or hypoglycemia in all Arg59Ter subjects. In vitro, IGF-IR-deficient Arg59Ter cells expressed less IGF-IR and unchanged insulin receptor (IR) protein. Receptor autophosphorylation and phosphorylation of downstream protein kinase B/Akt exhibited resistance to IGF-I but showed an augmented response to insulin in Arg59Ter cells. Decreased IGF-IR content was accompanied by a reduction of IGF-IR/IR receptor hybrids, and therefore, increased levels of IR/IR homodimers probably explain increased insulin-stimulated receptor autophosphorylation and Akt phosphorylation. CONCLUSIONS In vivo and in vitro IGF-I resistance in Arg59Ter subjects and fibroblasts indicates a human IGF1R gene dosage effect involving not only the IGF-IR, but also IGF-IR/IR hybrids. The abundance of both the IGF-IR protein and IGF-IR/IR hybrid receptors may have an impact on human growth, organ function, and glucose metabolism.
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Affiliation(s)
- K Raile
- Pediatric Endocrinology and Diabetes, Charité-Universitätsmedizin Berlin, Augustenburgerplatz 1, D-13353 Berlin, Germany.
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Mooradian AD, Haas MJ, Wong NCW. The effect of select nutrients on serum high-density lipoprotein cholesterol and apolipoprotein A-I levels. Endocr Rev 2006; 27:2-16. [PMID: 16243964 DOI: 10.1210/er.2005-0013] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol (HDLc). Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). The low plasma concentrations of HDL could be the result of increased fractional clearance and reduced expression of apo A-I. To this end, nutrients play an important role in modulating the fractional clearance rate, as well as the rate of apo A-I gene expression. Because medical nutrition therapy constitutes the cornerstone of management of dyslipidemias, it is essential to understand the mechanisms underlying the changes in HDL level in response to alterations in dietary intake. In this review, we will discuss the effect of select nutrients on serum HDLc and apo A-I levels. Specifically, we will review the literature on the effect of carbohydrates, fatty acids, and ketones, as well as some of the nutrient-related metabolites, such as glucosamine and the prostanoids, on apo A-I gene expression. Because there are multiple mechanisms involved in the regulation of serum HDLc levels, changes in gene transcription do not necessarily correlate with clinical observations on serum levels of HDLc.
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Affiliation(s)
- Arshag D Mooradian
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, St. Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, Missouri 63104, USA.
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Chisalita SI, Arnqvist HJ. Expression and function of receptors for insulin-like growth factor-I and insulin in human coronary artery smooth muscle cells. Diabetologia 2005; 48:2155-61. [PMID: 16094530 DOI: 10.1007/s00125-005-1890-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Accepted: 04/28/2005] [Indexed: 01/28/2023]
Abstract
AIMS/HYPOTHESIS Hyperinsulinaemia and insulin resistance, as well as low IGF-I, have been implicated in the pathogenesis of cardiovascular disease. Little is known about direct effects of IGF-I and insulin on human coronary artery smooth muscle cells (HCASMCs). Our aim was to characterise the expression and function of IGF-I receptor (IGF-IR) and insulin receptor (IR) in HCASMCs. MATERIALS AND METHODS Cultured HCASMCs were used. mRNA expression was measured by quantitative real-time RT-PCR analysis. Receptor proteins, phosphorylation of beta-subunits and the presence of hybrid IR/IGF-IR were analysed by immunoprecipitation and western blotting. DNA synthesis and glucose metabolism were assessed using [3H]thymidine incorporation and D-[U-14C]glucose accumulation respectively. RESULTS The mRNA expression of IGF-IR was approximately eight-fold higher than that of IR in HCASMCs. The presence of IGF-IR and IR could be demonstrated by immunoprecipitation and western blot analysis. Phosphorylation of the IGF-IR beta-subunit was obtained by IGF-I at 10(-10)-10(-8) mol/l and insulin at 10(-8) mol/l. Insulin and IGF-I at 10(-10)-10(-9) mol/l phosphorylated the IR beta-subunit. When immunoprecipitated with monoclonal anti-IR alpha-subunit or IGF-IR alpha-subunit antibodies, we found bands in slightly different positions, suggesting the presence of hybrid IR/IGF-IR. IGF-I at 10(-9)-10(-8) mol/l significantly stimulated [3H]thymidine incorporation and at a concentration of 10(-9)-10(-7) mol/l also D-[U-14C]glucose accumulation in HCASMCs. Insulin at 10(-9)-10(-7) mol/l had no effect on DNA synthesis, but increased glucose accumulation at 10(-7) mol/l. CONCLUSIONS/INTERPRETATION Our study provides experimental evidence that IGF-IR and possibly hybrid IR/IGF-IR play a role in HCASMCs.
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Affiliation(s)
- S I Chisalita
- Division of Cell Biology, Department of Biomedicine and Surgery, Faculty of Health Sciences, Linköping University, S-58185 Linköping, Sweden
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Authier F, Kouach M, Briand G. Endosomal proteolysis of insulin-like growth factor-I at its C-terminal D-domain by cathepsin B. FEBS Lett 2005; 579:4309-16. [PMID: 16051222 DOI: 10.1016/j.febslet.2005.06.066] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 06/13/2005] [Accepted: 06/28/2005] [Indexed: 11/21/2022]
Abstract
IGF-I is degraded within the endosomal apparatus as a consequence of receptor-mediated endocytosis. However, the nature of the responsible protease and the position of the cleavage sites in the IGF-I molecule remain undefined. In vitro proteolysis of IGF-I using an endosomal lysate required an acidic pH and was sensitive to CA074, an inhibitor of the cathepsin B enzyme. By nondenaturing immunoprecipitation, the acidic IGF-I-degrading activity was attributed to the luminal species of endosomal cathepsin B with apparent molecular masses of 32- and 28-kDa. The cathepsin B precursor, procathepsin B, was processed in vitro within isolated endosomes at pH 5 or at 7 in the presence of ATP, the substrate of the vacuolar H(+)-ATPase. The rate of IGF-I hydrolysis using an endosomal lysate or pure cathepsin B was found to be optimal at pH 5-6 and moderate at pH 4 and 7. Competition studies revealed that EGF and IGF-I share a common binding site on the cathepsin B enzyme, with native IGF-I displaying the lowest affinity for the protease (IC50 approximately 1.5 microM). Hydrolysates of IGF-I generated at low pH by endosomal IGF-I-degrading activity and analyzed by reverse-phase HPLC and mass spectrometry revealed cleavage sites at Lys68-Ser69, Ala67-Lys68, Pro66-Ala67 and Lys65-Pro66 within the C-terminal D-domain of IGF-I. Treatment of human HepG2 hepatoma cells with the cathepsin B proinhibitor CA074-Me reduced, in vivo, the intracellular degradation of internalized [125I]IGF-I and, in vitro, the degradation of exogenous [125I]IGF-I incubated with the cell-lysates at pH 5. Inhibitors of cathepsin B and pro-cathepsin B processing, which abolish endosomal proteolysis of IGF-I and alter tumor cell growth and IGF-I receptor signalling, merit investigation as antimetastatic drugs.
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Affiliation(s)
- François Authier
- Institut National de la Santé et de la Recherche Médicale U510, Faculté de Pharmacie, Paris XI, 5 Rue Jean Baptiste Clement, 92296 Châtenay-Malabry, France.
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Anderson JW, Nicolosi RJ, Borzelleca JF. Glucosamine effects in humans: a review of effects on glucose metabolism, side effects, safety considerations and efficacy. Food Chem Toxicol 2005; 43:187-201. [PMID: 15621331 DOI: 10.1016/j.fct.2004.11.006] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 11/09/2004] [Indexed: 11/22/2022]
Abstract
Glucosamine is widely used to relieve symptoms from osteoarthritis. Its safety and effects on glucose metabolism are critically evaluated in this review. The LD50 of oral glucosamine in animals is approximately 8000 mg/kg with no adverse effects at 2700 mg/kg for 12 months. Because altered glucose metabolism can be associated with parenteral administration of large doses of glucosamine in animals and with high concentrations in in vitro studies, we critically evaluated the clinical importance of these effects. Oral administration of large doses of glucosamine in animals has no documented effects on glucose metabolism. In vitro studies demonstrating effects of glucosamine on glucose metabolism have used concentrations that are 100-200 times higher than tissue levels expected with oral glucosamine administration in humans. We reviewed clinical trial data for 3063 human subjects. Fasting plasma glucose values decreased slightly for subjects after oral glucosamine for approximately 66 weeks. There were no adverse effects of oral glucosamine administration on blood, urine or fecal parameters. Side effects were significantly less common with glucosamine than placebo or non-steroidal anti-inflammatory drugs (NSAID). In contrast to NSAID, no serious or fatal side effects have been reported for glucosamine. Our critical evaluation indicates that glucosamine is safe under current conditions of use and does not affect glucose metabolism.
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Affiliation(s)
- J W Anderson
- Department of Internal Medicine, University of Kentucky, 1030 South Broadway, Suite 5, Lexington KY 40504-2681, USA.
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Haas MJ, Wong NCW, Mooradian AD. Effect of glucosamine on apolipoprotein AI mRNA stabilization and expression in HepG2 cells. Metabolism 2004; 53:766-71. [PMID: 15164326 DOI: 10.1016/j.metabol.2003.11.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Previously published studies suggest that an alteration in hexosamine flux induces a state of insulin resistance in muscle, liver, and other cell types. Glucosamine also alters the expression of several genes through an effect on transcription factors such as Sp1. Since the anti-atherogenic protein apolipoprotein AI (apoAI) is positively regulated by insulin, at least partly through its effect on Sp1, we investigated the effect of glucosamine on apoAI gene expression in the hepatocyte cell line, HepG2. By 24 hours of treatment with 0.1, 1, or 3 mmol/L glucosamine, the amount of apoAI protein secreted into the culture media increased 1.8-fold, 5.5-fold, and 2.3-fold, respectively. The decline in apoAI secretion at the highest glucosamine levels may be due to toxicity since the percentage of cells able to exclude trypan blue was lower in this group than in control cells (98.5% +/- 1.5% in control cells v 89.2% +/- 2.1% in cells treated with 3 mmol/L glucosamine, P <.01). ApoAI mRNA levels increased 2.4-fold in hepatocytes treated with 1 mmol/L glucosamine for 24 hours (1,158.1 +/- 78.8 v 482.2 +/- 24.3 arbitrary integrator units [AIU], P <.02), suggesting that the increase in apoAI protein secretion was due, at least partly, to an increase in apoAI mRNA levels. However, glucosamine had no effect on apoAI gene transcription rate as measured by nuclear runoff analysis (3,155 +/- 46.0 in control cells v 3,181 +/- 30.0 AIU in glucosamine-treated cells). Similarly, apoAI promoter activity measured in HepG2 cell transfected with an apoAI reporter plasmid containing the full-length apoAI promoter including an insulin-responsive Sp1 binding site did not change with glucosamine addition. In this assay, the chloramphenicol acetyltransferase (CAT) activity was 12.4% +/- 3.1%, 10.1% +/- 2.4%, 9.8% +/- 2.0%, 9.7% +/- 2.2%, and 11.9% +/- 2.9% in cells treated with 0, 0.03, 0.1, 0.3, and 1 mmol/L glucosamine, respectively. The apoAI mRNA turnover studies showed that 1 mmol/L glucosamine treatment of HepG2 cells was associated with increased apoAI mRNA half-life, from 7.6 to 16.6 hours. These findings suggest that increases in apoAI gene expression by glucosamine occur primarily through stabilizing apoAI mRNA.
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Affiliation(s)
- Michael J Haas
- Division of Endocrinology, Diabetes and Metabolism, Saint Louis University School of Medicine, St Louis, MO, USA
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