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Lyu Z, Chan YT, Lu Y, Fung Lam T, Wu X, Wu J, Xu L, Yang W, Zhang C, Lidan Zhong L, Wang N. Osteoprotegerin mediates adipogenesis in obesity. J Adv Res 2024; 62:245-255. [PMID: 38906326 PMCID: PMC11331166 DOI: 10.1016/j.jare.2024.06.018] [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: 02/08/2024] [Revised: 06/03/2024] [Accepted: 06/18/2024] [Indexed: 06/23/2024] Open
Abstract
INTRODUCTION Adipogenesis, the process of white adipose tissue expansion, plays a critical role in the development of obesity. Osteoprotegerin (OPG), known for its role in bone metabolism regulation, emerges as a potential regulator in mediating adipogenesis during obesity onset. OBJECTIVES This study aims to elucidate the involvement of OPG in adipogenesis during the early phases of diet-induced obesity and explore its therapeutic potential in obesity management. METHODS Using a diet-induced obesity model, we investigated OPG expression patterns in adipocytes and explored the mechanisms underlying its involvement in adipogenesis. We also assessed the effects of targeted silencing of OPG and recombinant OPG administration on obesity progression and insulin resistance. Additionally, the impact of electroacupuncture treatment on OPG levels and obesity management was evaluated in both animal models and human participants. RESULTS OPG expression was prominently activated in adipocytes of white adipose tissues during the early phase of diet-induced obesity. Hyperlipidemia induced Cbfa1-dependent OPG transcription, initiating and promoting adipogenesis, leading to cell-size expansion and lipid storage. Intracellular OPG physically bound to RAR and released the PPARɤ/RXR complex, activating adipogenesis-associated gene expression. Targeted silencing of OPG suppressed obesity development, while recombinant OPG administration promoted disease progression and insulin resistance in obese mice. Electroacupuncture treatment suppressed obesity development in an OPG-dependent manner and improved obesity parameters in obese human participants. CONCLUSION OPG emerges as a key regulator in mediating adipogenesis during obesity development. Targeting OPG holds promise for the prevention and treatment of obesity, as evidenced by the efficacy of electroacupuncture treatment in modulating OPG levels and managing obesity-related outcomes.
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Affiliation(s)
- Zipan Lyu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yau-Tuen Chan
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Yuanjun Lu
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Tsz Fung Lam
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Xingyao Wu
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Junyu Wu
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Lin Xu
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Wei Yang
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Cheng Zhang
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Linda Lidan Zhong
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore; School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.
| | - Ning Wang
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
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Xu Z, Huang S, Song Y, Xu C, Yan H, Linkun O, Lv B, Yuan F, Xu B, Wang H, Xi R, Yu JK. Identification of eight genes associated with recurrent patellar dislocation. iScience 2024; 27:109697. [PMID: 38680665 PMCID: PMC11046295 DOI: 10.1016/j.isci.2024.109697] [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: 09/18/2023] [Revised: 02/05/2024] [Accepted: 04/05/2024] [Indexed: 05/01/2024] Open
Abstract
The inheritance of recurrent patellar dislocation (RPD) is known, but the susceptible gene remains unidentified. Here, we performed the first whole exome sequencing (WES) cohort study to identify the susceptible genes. The results showed eight genes were associated with this disease. Notably, the carboxypeptidase D (CPD) gene showed the highest relevance based on its gene function and tissue expression. Single-cell sequencing results indicate that the CPD gene is involved in the pathophysiological process of RPD through granulocytes. Implicated pathways include nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and Wnt/β-catenin signaling, potentially influencing CPD's role in RPD pathogenesis. This study identified the susceptible gene and investigates the potential pathogenesis of RPD, which provided a new prospect for the understanding of RPD. Besides, it would offer the theoretical basis for disease prevention and genetic counseling.
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Affiliation(s)
- Zijie Xu
- Sports Medicine Department, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Beijing, China
- Institute of Sports Medicine, Peking University, Beijing, China
| | - Siyuan Huang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Yifan Song
- Orthopaedic Sports Medicine Center, Beijing Tsinghua Changgung Hospital, Affiliated Hospital of Tsinghua University, Beijing, China
| | - Chao Xu
- The Department of Joint Surgery and Sports Medicine, The Second Affiliated Hospital of Xinjiang Medical University, Urumchi, China
| | - Hongyu Yan
- Department of Pediatric Neurology, Children’s Hospital Affiliated to the Capital Institute of Pediatrics, Peking University, Beijing, China
| | - Ouyang Linkun
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Bo Lv
- Department of Orthopedics, People’s Hospital of Guilin, Guilin, Guangxi, China
| | - Fuzhen Yuan
- Sports Medicine Department, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Beijing, China
- Institute of Sports Medicine, Peking University, Beijing, China
| | - Bingbing Xu
- Sports Medicine Department, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Beijing, China
- Institute of Sports Medicine, Peking University, Beijing, China
| | - Haijun Wang
- Sports Medicine Department, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Beijing, China
- Institute of Sports Medicine, Peking University, Beijing, China
| | - Ruibin Xi
- School of Mathematical Sciences and Center for Statistical Science, Peking University, Beijing, China
| | - Jia-Kuo Yu
- Orthopaedic Sports Medicine Center, Beijing Tsinghua Changgung Hospital, Affiliated Hospital of Tsinghua University, Beijing, China
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Lin J, Huang C, Diao W, Liu H, Lu H, Huang S, Wang J. CPE correlates with poor prognosis in gastric cancer by promoting tumourigenesis. Heliyon 2024; 10:e29901. [PMID: 38694095 PMCID: PMC11058891 DOI: 10.1016/j.heliyon.2024.e29901] [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: 12/04/2023] [Revised: 04/16/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
Aims To investigate the potential functions and mechanisms of tumourigenesis in carboxypeptidase E (CPE) and its prognostic value in gastric cancer, and to develop a predictive model for prognosis based on CPE. Results Transcriptome level variation and the prognostic value of CPE in different types of cancers were investigated using bioinformatics analyses. The association between CPE and clinicopathological characteristics was specifically explored in gastric cancer. Elevated CPE expression was associated with poor survival and recurrence prognosis and was found in cases with a later clinical stage of gastric cancer. The CPE was considered an independent prognostic factor, as assessed using Cox regression analysis. The prognostic value of CPE was further verified through immunohistochemistry and haematoxylin staining. Enrichment analysis provided a preliminary confirmation of the potential functions and mechanisms of CPE. Immune cell infiltration analysis revealed a significant correlation between CPE and macrophage infiltration. Eventually, a prognosis prediction nomogram model based on CPE was developed. Conclusion CPE was identified as an independent biomarker associated with poor prognosis in gastric cancer. This suggests that CPE overexpression promoted epithelial-mesenchymal transition via the activation of the Erk/Wnt pathways, leading to proliferation, invasion, and metastasis. Targeted therapeutic strategies for gastric cancer may benefit from these findings.
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Affiliation(s)
- Jiarui Lin
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
| | - Chengzhi Huang
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
- Department of General Surgery, Guangdong Provincial People's Hospital Ganzhou Hospital (Ganzhou Municipal Hospital), Ganzhou, 341000, China
- School of Medicine, South China University of Technology, Guangzhou, 510006, China
| | - Wenfei Diao
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
- Shantou University Medical College, Shantou, 515000, China
| | - Haoming Liu
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
| | - Hesong Lu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 510080, China
| | - Shengchao Huang
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
| | - Junjiang Wang
- Department of Gastrointestinal Surgery, Department of General Surgery, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510080, China
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4
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Chen D, Wan B, Cheng Y, Luo Y, Bai X, Guo J, Li G, Jin T, Nie J, Liu W, Wang R. Carboxypeptidase E is a prognostic biomarker co-expressed with osteoblastic genes in osteosarcoma. PeerJ 2023; 11:e15814. [PMID: 37663298 PMCID: PMC10474831 DOI: 10.7717/peerj.15814] [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: 03/30/2023] [Accepted: 07/10/2023] [Indexed: 09/05/2023] Open
Abstract
Osteosarcoma (OS) is a rare primary malignant bone tumor in adolescents and children with a poor prognosis. The identification of prognostic genes lags far behind advancements in treatment. In this study, we identified differential genes using mRNA microarray analysis of five paired OS tissues. Hub genes, gene set enrichment analysis, and pathway analysis were performed to gain insight into the pathway alterations of OS. Prognostic genes were screened using the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) dataset, then overlapped with the differential gene dataset. The carboxypeptidase E (CPE) gene, found to be an independent risk factor, was further validated using RT-PCR and Gene Expression Omnibus (GEO) datasets. Additionally, we explored the specific expression of CPE in OS tissues by reanalyzing single-cell genomics. Interestingly, CPE was found to be co-expressed with osteoblast lineage cell clusters that expressed RUNX2, SP7, SPP1, and IBSP marker genes in OS. These results suggest that CPE could serve as a prognostic factor in osteoblastic OS and should be further investigated as a potential therapeutic target.
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Affiliation(s)
- Dafu Chen
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Ben Wan
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
- Department of Oral and Maxillofacial Surgery, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Yuning Cheng
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Yuwen Luo
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Xueshan Bai
- Cranio-Maxillo-Facial Surgery Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jianxun Guo
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Guangping Li
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Tao Jin
- Depatment of Orthopaedic Oncology Surgery, National Center for Orthopaedics, Beijing JiShuiTan Hospital, Capital Medical University, Beijing, China
| | - Jingjun Nie
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
| | - Weifeng Liu
- Depatment of Orthopaedic Oncology Surgery, National Center for Orthopaedics, Beijing JiShuiTan Hospital, Capital Medical University, Beijing, China
| | - Renxian Wang
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
- JST Sarcopenia Research Centre, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China
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5
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Weeks EM, Ulirsch JC, Cheng NY, Trippe BL, Fine RS, Miao J, Patwardhan TA, Kanai M, Nasser J, Fulco CP, Tashman KC, Aguet F, Li T, Ordovas-Montanes J, Smillie CS, Biton M, Shalek AK, Ananthakrishnan AN, Xavier RJ, Regev A, Gupta RM, Lage K, Ardlie KG, Hirschhorn JN, Lander ES, Engreitz JM, Finucane HK. Leveraging polygenic enrichments of gene features to predict genes underlying complex traits and diseases. Nat Genet 2023; 55:1267-1276. [PMID: 37443254 PMCID: PMC10836580 DOI: 10.1038/s41588-023-01443-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 06/09/2023] [Indexed: 07/15/2023]
Abstract
Genome-wide association studies (GWASs) are a valuable tool for understanding the biology of complex human traits and diseases, but associated variants rarely point directly to causal genes. In the present study, we introduce a new method, polygenic priority score (PoPS), that learns trait-relevant gene features, such as cell-type-specific expression, to prioritize genes at GWAS loci. Using a large evaluation set of genes with fine-mapped coding variants, we show that PoPS and the closest gene individually outperform other gene prioritization methods, but observe the best overall performance by combining PoPS with orthogonal methods. Using this combined approach, we prioritize 10,642 unique gene-trait pairs across 113 complex traits and diseases with high precision, finding not only well-established gene-trait relationships but nominating new genes at unresolved loci, such as LGR4 for estimated glomerular filtration rate and CCR7 for deep vein thrombosis. Overall, we demonstrate that PoPS provides a powerful addition to the gene prioritization toolbox.
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Affiliation(s)
- Elle M Weeks
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
| | - Jacob C Ulirsch
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
- Artificial Intelligence Laboratory, Illumina, Inc., San Diego, CA, USA
| | | | - Brian L Trippe
- Program in Computational & Systems Biology, MIT, Cambridge, MA, USA
- Computer Science & Artificial Intelligence Lab, MIT, Cambridge, MA, USA
| | - Rebecca S Fine
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Endocrinology and Center for Basic and Translational Obesity Research, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Vertex Pharmaceuticals Incorporated, Boston, MA, USA
| | - Jenkai Miao
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Endocrinology and Center for Basic and Translational Obesity Research, Boston Children's Hospital, Boston, MA, USA
| | - Tejal A Patwardhan
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Statistics, Harvard University, Cambridge, MA, USA
| | - Masahiro Kanai
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Analytic and Translational Genetics Unit, MGH, Boston, MA, USA
- Program in Bioinformatics and Integrative Genomics, Harvard Medical School, Boston, MA, USA
- Department of Statistical Genetics, Osaka University Graduate School of Medicine, Suita, Japan
| | - Joseph Nasser
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Charles P Fulco
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Bristol Myers Squibb, Cambridge, MA, USA
| | | | | | - Taibo Li
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- MD-PhD Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jose Ordovas-Montanes
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Gastroenterology, Hepatology, and Nutrition, Boston Children's Hospital, Boston, MA, USA
- Program in Immunology, Harvard Medical School, Boston, MA, USA
- Harvard Stem Cell Institute, Cambridge, MA, USA
| | - Christopher S Smillie
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Program in Computational & Systems Biology, MIT, Cambridge, MA, USA
| | - Moshe Biton
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Molecular Biology, MGH, Boston, MA, USA
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Alex K Shalek
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Institute for Medical Engineering and Science, MIT, Cambridge, MA, USA
- Department of Chemistry, MIT, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, MIT, Cambridge, MA, USA
- Ragon Institute of MGH, MMIT, Cambridge, MA, USA
| | - Ashwin N Ananthakrishnan
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, MGH, Boston, MA, USA
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Molecular Biology, MGH, Boston, MA, USA
- Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, MGH, Boston, MA, USA
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Aviv Regev
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, MIT, Cambridge, MA, USA
- Howard Hughes Medical Institute, MIT, Cambridge, MA, USA
- Genentech, San Francisco, CA, USA
| | - Rajat M Gupta
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Cardiovascular Medicine and Genetics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Kasper Lage
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Surgery, MGH, Boston, MA, USA
| | - Kristin G Ardlie
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Joel N Hirschhorn
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Endocrinology and Center for Basic and Translational Obesity Research, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Eric S Lander
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Biology, MIT, Cambridge, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Jesse M Engreitz
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
- BASE Initiative, Betty Irene Moore Children's Heart Center, Lucile Packard Children's Hospital, Stanford University School of Medicine, Stanford, CA, USA
| | - Hilary K Finucane
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Analytic and Translational Genetics Unit, MGH, Boston, MA, USA.
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Fricker LD, Lemos Duarte M, Jeltyi A, Lueptow L, Fakira AK, Tashima AK, Hochgeschwender U, Wetsel WC, Devi LA. Mice heterozygous for a null mutation of Cpe show reduced expression of carboxypeptidase E mRNA and enzyme activity but normal physiology, behavior, and levels of neuropeptides. Brain Res 2022; 1789:147951. [PMID: 35618016 DOI: 10.1016/j.brainres.2022.147951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/18/2022] [Accepted: 05/19/2022] [Indexed: 11/02/2022]
Abstract
Carboxypeptidase E (CPE) is an essential enzyme that contributes to the biosynthesis of the vast majority of neuropeptides and peptide hormones. There are several reports claiming that small decreases in CPE activity cause physiological changes in animals and/or cultured cells, but these studies did not provide evidence that neuropeptide levels were affected by decreased CPE activity. In the present study, we tested if CPE is a rate-limiting enzyme in neuropeptide production using CpeNeo mice, which contain a neomycin cassette within the Cpe gene that eliminates enzyme expression. Homozygous CpeNeo/Neo mice show defects found in Cpefat/fat and/or Cpe global knockout (KO) mice, including greatly decreased levels of most neuropeptides, severely impaired fertility, depressive-like behavior, adult-onset obesity, and anxiety-like behavior. Removal of the neomycin cassette with Flp recombinase under a germline promoter restored expression of CPE activity and resulted in normal behavioral and physiological properties, including levels of neuropeptides. Mice heterozygous for the CpeNeo allele have greatly reduced levels of Cpe mRNA and CPE-like enzymatic activity. Despite the decreased levels of Cpe expression, heterozygous CpeNeo mice are behaviorally and physiologically identical to wild-type mice, with normal levels of most neuropeptides. These results indicate that CPE is not a rate-limiting enzyme in the production of most neuropeptides, casting doubt upon studies claiming small decreases in CPE activity contribute to obesity or other physiological effects.
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Affiliation(s)
- Lloyd D Fricker
- Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461.
| | - Mariana Lemos Duarte
- Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, 10029.
| | - Andrei Jeltyi
- Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, 10029.
| | - Lindsay Lueptow
- Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, 10029.
| | - Amanda K Fakira
- Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, 10029.
| | - Alexandre K Tashima
- Department of Biochemistry, Escola Paulista de Medicina, Federal University of Sao Paulo, Sao Paulo, SP 04023-901, Brazil.
| | | | - William C Wetsel
- Departments of Psychiatry and Behavioral Sciences, Neurobiology, and Cell Biology, Duke University Medical Center, Durham, NC, 27710.
| | - Lakshmi A Devi
- Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, NY, NY, 10029.
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7
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Lindberg I, Fricker LD. Obesity, POMC, and POMC-processing Enzymes: Surprising Results From Animal Models. Endocrinology 2021; 162:6333651. [PMID: 34333593 PMCID: PMC8489426 DOI: 10.1210/endocr/bqab155] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Indexed: 11/19/2022]
Abstract
Peptides derived from proopiomelanocortin (POMC) are well-established neuropeptides and peptide hormones that perform multiple functions, including regulation of body weight. In humans and some animals, these peptides include α- and β-melanocyte-stimulating hormone (MSH). In certain rodent species, no β-MSH is produced from POMC because of a change in the cleavage site. Enzymes that convert POMC into MSH include prohormone convertases (PCs), carboxypeptidases (CPs), and peptidyl-α-amidating monooxygenase (PAM). Humans and mice with inactivating mutations in either PC1/3 or carboxypeptidase E (CPE) are obese, which was assumed to result from defective processing of POMC into MSH. However, recent studies have shown that selective loss of either PC1/3 or CPE in POMC-expressing cells does not cause obesity. These findings suggest that defects in POMC processing cannot alone account for the obesity observed in global PC1/3 or CPE mutants. We propose that obesity in animals lacking PC1/3 or CPE activity depends, at least in part, on deficient processing of peptides in non-POMC-expressing cells either in the brain and/or the periphery. Genetic background may also contribute to the manifestation of obesity.
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Affiliation(s)
- Iris Lindberg
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
- Correspondence: I. Lindberg, PhD, Department of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn St, Baltimore, MD 21201, USA.
| | - Lloyd D Fricker
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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8
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Abood A, Farber CR. Using "-omics" Data to Inform Genome-wide Association Studies (GWASs) in the Osteoporosis Field. Curr Osteoporos Rep 2021; 19:369-380. [PMID: 34125409 PMCID: PMC8767463 DOI: 10.1007/s11914-021-00684-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/22/2021] [Indexed: 01/12/2023]
Abstract
PURPOSE OF REVIEW Osteoporosis constitutes a major societal health problem. Genome-wide association studies (GWASs) have identified over 1100 loci influencing bone mineral density (BMD); however, few of the causal genes have been identified. Here, we review approaches that use "-omics" data and genetic- and systems genetics-based analytical strategies to facilitate causal gene discovery. RECENT FINDINGS The bone field is beginning to adopt approaches that are commonplace in other disease disciplines. The slower progress has been due in part to the lack of large-scale "omics" data on bone and bone cells. This is however changing, and approaches such as eQTL colocalization, transcriptome-wide association studies (TWASs), network, and integrative approaches are beginning to provide significant insight into the genes responsible for BMD GWAS associations. The use of "-omics" data to inform BMD GWASs has increased in recent years, leading to the identification of novel regulators of BMD in humans. The ultimate goal will be to use this information to develop more effective therapies to treat and ultimately prevent osteoporosis.
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Affiliation(s)
- Abdullah Abood
- Center for Public Health Genomics, University of Virginia, 800717, Charlottesville, VA, 22908, USA
- Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Charles R Farber
- Center for Public Health Genomics, University of Virginia, 800717, Charlottesville, VA, 22908, USA.
- Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA.
- Department of Public Health Sciences, University of Virginia, Charlottesville, VA, 22908, USA.
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9
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Ramzy A, Kieffer TJ. Altered islet prohormone processing: A cause or consequence of diabetes? Physiol Rev 2021; 102:155-208. [PMID: 34280055 DOI: 10.1152/physrev.00008.2021] [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] [Indexed: 02/07/2023] Open
Abstract
Peptide hormones are first produced as larger precursor prohormones that require endoproteolytic cleavage to liberate the mature hormones. A structurally conserved but functionally distinct family of nine prohormone convertase enzymes (PCs) are responsible for cleavage of protein precursors of which PC1/3 and PC2 are known to be exclusive to neuroendocrine cells and responsible for prohormone cleavage. Differential expression of PCs within tissues define prohormone processing; whereas glucagon is the major product liberated from proglucagon via PC2 in pancreatic α-cells, proglucagon is preferentially processed by PC1/3 in intestinal L cells to produce glucagon-like peptides 1 and 2 (GLP-1, GLP-2). Beyond our understanding of processing of islet prohormones in healthy islets, there is convincing evidence that proinsulin, proIAPP, and proglucagon processing is altered during prediabetes and diabetes. There is predictive value of elevated circulating proinsulin or proinsulin : C-peptide ratio for progression to type 2 diabetes and elevated proinsulin or proinsulin : C-peptide is predictive for development of type 1 diabetes in at risk groups. After onset of diabetes, patients have elevated circulating proinsulin and proIAPP and proinsulin may be an autoantigen in type 1 diabetes. Further, preclinical studies reveal that α-cells have altered proglucagon processing during diabetes leading to increased GLP-1 production. We conclude that despite strong associative data, current evidence is inconclusive on the potential causal role of impaired prohormone processing in diabetes, and suggest that future work should focus on resolving the question of whether altered prohormone processing is a causal driver or merely a consequence of diabetes pathology.
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Affiliation(s)
- Adam Ramzy
- Laboratory of Molecular and Cellular Medicine, Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Timothy J Kieffer
- Laboratory of Molecular and Cellular Medicine, Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada
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10
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Xiao L, Sharma VK, Toulabi L, Yang X, Lee C, Abebe D, Peltekian A, Arnaoutova I, Lou H, Loh YP. Neurotrophic factor-α1, a novel tropin is critical for the prevention of stress-induced hippocampal CA3 cell death and cognitive dysfunction in mice: comparison to BDNF. Transl Psychiatry 2021; 11:24. [PMID: 33414376 PMCID: PMC7791060 DOI: 10.1038/s41398-020-01112-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 09/15/2020] [Accepted: 10/22/2020] [Indexed: 12/16/2022] Open
Abstract
Stress leads to brain pathology including hippocampal degeneration, cognitive dysfunction, and potential mood disorders. Hippocampal CA3, a most stress-vulnerable region, consists of pyramidal neurons that regulate cognitive functions e.g. learning and memory. These CA3 neurons express high levels of the neuroprotective protein, neurotrophic factor-α1 (NF-α1), also known as carboxypeptidase E (CPE), and receive contacts from granule cell projections that release BDNF which has neuroprotective activity. Whether NF-α1-CPE and/or BDNF are critical in protecting these CA3 neurons against severe stress-induced cell death is unknown. Here we show that social combined with the physical stress of maternal separation, ear tagging, and tail snipping at weaning in 3-week-old mice lacking NF-α1-CPE, led to complete hippocampal CA3 degeneration, despite having BDNF and active phosphorylated TrkB receptor levels similar to WT animals. Mice administered TrkB inhibitor, ANA12 which blocked TrkB phosphorylation showed no degeneration of the CA3 neurons after the weaning stress paradigm. Furthermore, transgenic knock-in mice expressing CPE-E342Q, an enzymatically inactive form, replacing NF-α1-CPE, showed no CA3 degeneration and exhibited normal learning and memory after the weaning stress, unlike NF-α1-CPE-KO mice. Mechanistically, we showed that radio-labeled NF-α1-CPE bound HT22 hippocampal cells in a saturable manner and with high affinity (Kd = 4.37 nM). Subsequently, treatment of the HT22cpe-/- cells with NF-α1-CPE or CPE-E342Q equivalently activated ERK signaling and increased BCL2 expression to protect these neurons against H2O2-or glutamate-induced cytotoxicity. Our findings show that NF-α1-CPE is more critical compared to BDNF in protecting CA3 pyramidal neurons against stress-induced cell death and cognitive dysfunction, independent of its enzymatic activity.
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Affiliation(s)
- Lan Xiao
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Vinay Kumar Sharma
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Leila Toulabi
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Xuyu Yang
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Cheol Lee
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Daniel Abebe
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Areg Peltekian
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Irina Arnaoutova
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Hong Lou
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
| | - Y. Peng Loh
- grid.94365.3d0000 0001 2297 5165Section on Cellular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892 USA
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11
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Neuropeptidomic Analysis of a Genetically Defined Cell Type in Mouse Brain and Pituitary. Cell Chem Biol 2020; 28:105-112.e4. [PMID: 33217339 DOI: 10.1016/j.chembiol.2020.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/09/2020] [Accepted: 11/02/2020] [Indexed: 12/12/2022]
Abstract
Neuropeptides and peptide hormones are important cell-cell signaling molecules that mediate many physiological processes. Unlike classic neurotransmitters, peptides undergo cell-type-specific post-translational modifications that affect their biological activity. To enable the identification of the peptide repertoire of a genetically defined cell type, we generated mice with a conditional disruption of the gene for carboxypeptidase E (Cpe), an essential neuropeptide-processing enzyme. The loss of Cpe leads to accumulation of neuropeptide precursors containing C-terminal basic residues, which serve as tags for affinity purification. The purified peptides are subsequently identified using quantitative peptidomics, thereby revealing the specific forms of neuropeptides in cells with the disrupted Cpe gene. To validate the method, we used mice expressing Cre recombinase under the proopiomelanocortin (Pomc) promoter and analyzed hypothalamic and pituitary extracts, detecting peptides derived from proopiomelanocortin (as expected) and also proSAAS in POMC neurons. This technique enables the analyses of specific forms of peptides in any Cre-expressing cell type.
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12
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Wang K, Mao W, Zhang X, Zhao Y, Fan K, Pan D, Liu H, Li P, Hai R, Du C. Neuroanatomy of melanocortin-4 receptor pathway in the mouse brain. Open Life Sci 2020; 15:580-587. [PMID: 33817246 PMCID: PMC7874588 DOI: 10.1515/biol-2020-0063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/27/2020] [Accepted: 05/01/2020] [Indexed: 12/30/2022] Open
Abstract
Objective Melanocortin-4 receptors (MC4Rs) are key regulators of energy homeostasis and adipose deposition in the central nervous system. Considering that MC4R expression regions and function-related research mainly focus on the paraventricular nucleus (PVN), little is known about their distribution throughout the mouse brain, although its messenger RNA distribution has been analyzed in the rat. Therefore, MC4R protein localization in mouse neurons was the focus of this study. Methods MC4R protein distribution was assessed in mice through immunofluorescence and Western blotting. Results MC4R was differentially expressed throughout the arcuate nucleus (ARC), nucleus of the solitary tract (NTS), raphe pallidus (RPa), medial cerebellar nucleus, intermediolateral nucleus, and brainstem. The highest MC4R protein levels were found in the ARC and ventromedial hypothalamic nucleus, while they were significantly lower in the parabrachial nucleus and NTS. The lowest MC4R protein levels were found in the PVN; there was no difference in the protein levels between the area postrema and RPa. Conclusions These data provide a basic characterization of MC4R-expressing neurons and protein distribution in the mouse brain and may aid further research on its role in energy homeostasis.
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Affiliation(s)
- Kun Wang
- Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050000, China
| | - Wei Mao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xiaoyu Zhang
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China
| | - Yufei Zhao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
| | - Kuikui Fan
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
| | - Deng Pan
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
| | - Haodong Liu
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
| | - Penghui Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
| | - Rihan Hai
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China
| | - Chenguang Du
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.,Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China.,Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot 010018, China
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13
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Chougule A, Kolli V, Baroi S, Ebraheim N, Czernik PJ, Loh YP, Lecka-Czernik B. Nonenzymatic and Trophic Activities of Carboxypeptidase E Regulate Bone Mass and Bioenergetics of Skeletal Stem Cells in Mice. JBMR Plus 2020; 4:e10392. [PMID: 32995694 PMCID: PMC7507073 DOI: 10.1002/jbm4.10392] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/24/2020] [Accepted: 06/30/2020] [Indexed: 12/20/2022] Open
Abstract
Bone and energy metabolism are integrated by common regulatory mechanisms. Carboxypeptidase E (CPE), also known as obesity susceptibility protein or neurotrophic factor‐α1, is recognized for its function in processing prohormones, including proinsulin and pro‐opiomelanocortin polypeptide. Independent of its enzymatic activity, CPE may also act as a secreted factor with divergent roles in neuroprotection and cancer growth; however, its role in the regulation of bone mass and skeletal cell differentiation is unknown. Male mice with global deficiency in CPE are characterized with profound visceral obesity, low bone mass in both appendicular and axial skeleton, and high volume of marrow fat. Interestingly, although metabolic deficit of CPE KO mice develops early in life, bone deficit develops in older age, suggesting that CPE bone‐specific activities differ from its enzymatic activities. Indeed, mutated CPE knockin (mCPE KI) mice ectopically expressing CPE‐E342Q, a mutated protein lacking enzymatic activity, develop the same obese phenotype and accumulate the same volume of marrow fat as CPE KO mice, but their bone mass is normal. In addition, differentiation of marrow hematopoietic cells toward tartrate‐resistant acid phosphatase‐positive multinucleated osteoclasts is highly increased in CPE KO mice, but normal in mCPE KI mice. Moreover, in murine skeletal stem cells, nonenzymatic trophic CPE has activated ERK signaling, increased cell proliferation and increased mitochondrial activity. Treatment of preosteoblastic cells with intact or mutated recombinant CPE led to a transient accumulation of small lipid droplets, increased oxidative phosphorylation, and increased cellular dependence on fatty acids as fuel for energy production. In human marrow aspirates, CPE expression increases up to 30‐fold in osteogenic conditions. These findings suggest that nonenzymatic and trophic activities of CPE regulate bone mass, whereas marrow adiposity is controlled by CPE enzymatic activity. Thus, CPE can be positioned as a factor regulating simultaneously bone and energy metabolism through a combination of shared and distinct mechanisms. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2020 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)
- Amit Chougule
- Department of Orthopaedic Surgery University of Toledo, College of Medicine and Life Sciences Toledo OH USA.,Center for Diabetes and Endocrine Research University of Toledo, College of Medicine and Life Sciences Toledo OH USA
| | - Vipula Kolli
- Section on Cellular Neurobiology Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health Bethesda MD USA
| | - Sudipta Baroi
- Department of Orthopaedic Surgery University of Toledo, College of Medicine and Life Sciences Toledo OH USA.,Center for Diabetes and Endocrine Research University of Toledo, College of Medicine and Life Sciences Toledo OH USA
| | - Nabil Ebraheim
- Department of Orthopaedic Surgery University of Toledo, College of Medicine and Life Sciences Toledo OH USA
| | - Piotr J Czernik
- Department of Physiology and Pharmacology University of Toledo, College of Medicine and Life Sciences Toledo OH USA
| | - Y Peng Loh
- Section on Cellular Neurobiology Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health Bethesda MD USA
| | - Beata Lecka-Czernik
- Department of Orthopaedic Surgery University of Toledo, College of Medicine and Life Sciences Toledo OH USA.,Department of Physiology and Pharmacology University of Toledo, College of Medicine and Life Sciences Toledo OH USA.,Center for Diabetes and Endocrine Research University of Toledo, College of Medicine and Life Sciences Toledo OH USA
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14
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Mullin BH, Tickner J, Zhu K, Kenny J, Mullin S, Brown SJ, Dudbridge F, Pavlos NJ, Mocarski ES, Walsh JP, Xu J, Wilson SG. Characterisation of genetic regulatory effects for osteoporosis risk variants in human osteoclasts. Genome Biol 2020; 21:80. [PMID: 32216834 PMCID: PMC7098081 DOI: 10.1186/s13059-020-01997-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 03/11/2020] [Indexed: 12/15/2022] Open
Abstract
Background Osteoporosis is a complex disease with a strong genetic contribution. A recently published genome-wide association study (GWAS) for estimated bone mineral density (eBMD) identified 1103 independent genome-wide significant association signals. Most of these variants are non-coding, suggesting that regulatory effects may drive many of the associations. To identify genes with a role in osteoporosis, we integrate the eBMD GWAS association results with those from our previous osteoclast expression quantitative trait locus (eQTL) dataset. Results We identify sixty-nine significant cis-eQTL effects for eBMD GWAS variants after correction for multiple testing. We detect co-localisation of eBMD GWAS and osteoclast eQTL association signals for 21 of the 69 loci, implicating a number of genes including CCR5, ZBTB38, CPE, GNA12, RIPK3, IQGAP1 and FLCN. Summary-data-based Mendelian Randomisation analysis of the eBMD GWAS and osteoclast eQTL datasets identifies significant associations for 53 genes, with TULP4 presenting as a strong candidate for pleiotropic effects on eBMD and gene expression in osteoclasts. By performing analysis using the GARFIELD software, we demonstrate significant enrichment of osteoporosis risk variants among high-confidence osteoclast eQTL across multiple GWAS P value thresholds. Mice lacking one of the genes of interest, the apoptosis/necroptosis gene RIPK3, show disturbed bone micro-architecture and increased osteoclast number, highlighting a new biological pathway relevant to osteoporosis. Conclusion We utilise a unique osteoclast eQTL dataset to identify a number of potential effector genes for osteoporosis risk variants, which will help focus functional studies in this area.
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Affiliation(s)
- Benjamin H Mullin
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia. .,School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.
| | - Jennifer Tickner
- School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Kun Zhu
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.,School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Jacob Kenny
- School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Shelby Mullin
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.,School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Suzanne J Brown
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia
| | - Frank Dudbridge
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - Nathan J Pavlos
- School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Edward S Mocarski
- Department of Microbiology and Immunology, Emory Vaccine Center, School of Medicine, Emory University, Atlanta, GA, USA
| | - John P Walsh
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.,Medical School, The University of Western Australia, Crawley, WA, Australia
| | - Jiake Xu
- School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Scott G Wilson
- Department of Endocrinology & Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA, Australia.,School of Biomedical Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Department of Twin Research & Genetic Epidemiology, King's College London, London, UK
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15
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Suleiman JB, Mohamed M, Bakar ABA. A systematic review on different models of inducing obesity in animals: Advantages and limitations. J Adv Vet Anim Res 2020; 7:103-114. [PMID: 32219116 PMCID: PMC7096124 DOI: 10.5455/javar.2020.g399] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 12/20/2022] Open
Abstract
Several animals have been in the limelight of basic research associated with metabolic diseases like obesity. Obesity can be considered as a significant public health concern in the world. It raises the chances for a variety of disease conditions that includes diabetes, hypertension, liver disease, and cancers, which, in turn, decreases the overall lifespan of adult men and women. The World Health Organization has considered obesity as a global epidemic. Researchers have made several attempts to classify human obesity, but none have been successful. Animal obesity can be classified based on their etiology; however, till now, no animal model of obesity can replicate models of the human condition, they have only provided clues into the causes, aftermaths, and preventive remedy to human adiposity. Over the years, there are varieties of animal models used to induce obesity. Some of them include monogenic, polygenic, surgical, seasonal, and other models of obesity. Apart from the advantages of these models, most of them are accompanied by limitations. The primary purpose of this review is, therefore, to highlight the several models with their advantages and limitations. By knowing the benefits and limitations of animal models of obesity, researchers may be at liberty to select the appropriate one for the study of obesity.
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Affiliation(s)
- Joseph Bagi Suleiman
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Malaysia
| | - Mahaneem Mohamed
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Malaysia
| | - Ainul Bahiyah Abu Bakar
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Malaysia
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16
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Harno E, Gali Ramamoorthy T, Coll AP, White A. POMC: The Physiological Power of Hormone Processing. Physiol Rev 2019; 98:2381-2430. [PMID: 30156493 DOI: 10.1152/physrev.00024.2017] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Pro-opiomelanocortin (POMC) is the archetypal polypeptide precursor of hormones and neuropeptides. In this review, we examine the variability in the individual peptides produced in different tissues and the impact of the simultaneous presence of their precursors or fragments. We also discuss the problems inherent in accurately measuring which of the precursors and their derived peptides are present in biological samples. We address how not being able to measure all the combinations of precursors and fragments quantitatively has affected our understanding of the pathophysiology associated with POMC processing. To understand how different ratios of peptides arise, we describe the role of the pro-hormone convertases (PCs) and their tissue specificities and consider the cellular processing pathways which enable regulated secretion of different peptides that play crucial roles in integrating a range of vital physiological functions. In the pituitary, correct processing of POMC peptides is essential to maintain the hypothalamic-pituitary-adrenal axis, and this processing can be disrupted in POMC-expressing tumors. In hypothalamic neurons expressing POMC, abnormalities in processing critically impact on the regulation of appetite, energy homeostasis, and body composition. More work is needed to understand whether expression of the POMC gene in a tissue equates to release of bioactive peptides. We suggest that this comprehensive view of POMC processing, with a focus on gaining a better understanding of the combination of peptides produced and their relative bioactivity, is a necessity for all involved in studying this fascinating physiological regulatory phenomenon.
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Affiliation(s)
- Erika Harno
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Thanuja Gali Ramamoorthy
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Anthony P Coll
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
| | - Anne White
- Division of Diabetes, Endocrinology and Gastrointestinal Sciences, Faculty of Biology, Medicine and Health, University of Manchester , Manchester , United Kingdom ; and MRC Metabolic Diseases Unit, Wellcome Trust-MRC Institute of Metabolic Science , Cambridge , United Kingdom
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17
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Ji L, Wu HT, Qin XY, Lan R. Dissecting carboxypeptidase E: properties, functions and pathophysiological roles in disease. Endocr Connect 2017; 6:R18-R38. [PMID: 28348001 PMCID: PMC5434747 DOI: 10.1530/ec-17-0020] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 03/27/2017] [Indexed: 01/02/2023]
Abstract
Since discovery in 1982, carboxypeptidase E (CPE) has been shown to be involved in the biosynthesis of a wide range of neuropeptides and peptide hormones in endocrine tissues, and in the nervous system. This protein is produced from pro-CPE and exists in soluble and membrane forms. Membrane CPE mediates the targeting of prohormones to the regulated secretory pathway, while soluble CPE acts as an exopeptidase and cleaves C-terminal basic residues from peptide intermediates to generate bioactive peptides. CPE also participates in protein internalization, vesicle transport and regulation of signaling pathways. Therefore, in two types of CPE mutant mice, Cpefat/Cpefat and Cpe knockout, loss of normal CPE leads to a lot of disorders, including diabetes, hyperproinsulinemia, low bone mineral density and deficits in learning and memory. In addition, the potential roles of CPE and ΔN-CPE, an N-terminal truncated form, in tumorigenesis and diagnosis were also addressed. Herein, we focus on dissecting the pathophysiological roles of CPE in the endocrine and nervous systems, and related diseases.
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Affiliation(s)
- Lin Ji
- Department of Cell Biology & Medical GeneticsSchool of Medicine, Shenzhen University, Shenzhen, China
| | - Huan-Tong Wu
- Beijing Engineering Research Center of Food Environment and HealthCollege of Life & Environmental Sciences, Minzu University of China, Beijing, China
| | - Xiao-Yan Qin
- Beijing Engineering Research Center of Food Environment and HealthCollege of Life & Environmental Sciences, Minzu University of China, Beijing, China
| | - Rongfeng Lan
- Department of Cell Biology & Medical GeneticsSchool of Medicine, Shenzhen University, Shenzhen, China
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18
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Fan S, Li X, Li L, Wang L, Du Z, Yang Y, Zhao J, Li Y. Silencing of carboxypeptidase E inhibits cell proliferation, tumorigenicity, and metastasis of osteosarcoma cells. Onco Targets Ther 2016; 9:2795-803. [PMID: 27274275 PMCID: PMC4869623 DOI: 10.2147/ott.s98991] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Carboxypeptidase E (CPE), a prohormone processing enzyme, has been implicated in the progression of multiple malignancies. However, the biological role and molecular mechanisms of CPE in osteosarcoma remain elusive. In this study, we assessed the effects of CPE on cell proliferation, tumorigenicity, migration, and invasion in osteosarcoma. Our results showed that silencing of CPE significantly inhibited cell proliferation, caused cell cycle arrest at G0/G1 phase, decreased the expression levels of cell cycle protein, cyclin D1, and inhibited tumorigenicity in vivo. Additionally, CPE downregulation repressed the migratory and invasive capacities of osteosarcoma cells in vitro. Furthermore, overexpression of CPE-ΔN (a splice variant of CPE) enhanced the cell growth, migration, and invasion of osteosarcoma cells. It is possible that both CPE forms are involved in the tumorigenesis and development of osteosarcoma, and therefore CPE may provide a promising biological target for osteosarcoma therapy.
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Affiliation(s)
- Shuli Fan
- Department of Geriatrics, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Xu Li
- Department of Sports Medicine and Joint Surgery, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Leiming Li
- Department of Sports Medicine and Joint Surgery, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Liguo Wang
- Department of Sports Medicine and Joint Surgery, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Zhangzhen Du
- Department of Sports Medicine and Joint Surgery, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yan Yang
- Department of Sports Medicine and Joint Surgery, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China
| | - Jiansong Zhao
- Department of Orthopaedic Surgery, Shengjing Hospital of China Medical University, Shenyang, People's Republic of China
| | - Yan Li
- Department of Orthopaedic Surgery, Shengjing Hospital of China Medical University, Shenyang, People's Republic of China
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Cawley NX, Li Z, Loh YP. 60 YEARS OF POMC: Biosynthesis, trafficking, and secretion of pro-opiomelanocortin-derived peptides. J Mol Endocrinol 2016; 56:T77-97. [PMID: 26880796 PMCID: PMC4899099 DOI: 10.1530/jme-15-0323] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 02/15/2016] [Indexed: 12/15/2022]
Abstract
Pro-opiomelanocortin (POMC) is a prohormone that encodes multiple smaller peptide hormones within its structure. These peptide hormones can be generated by cleavage of POMC at basic residue cleavage sites by prohormone-converting enzymes in the regulated secretory pathway (RSP) of POMC-synthesizing endocrine cells and neurons. The peptides are stored inside the cells in dense-core secretory granules until released in a stimulus-dependent manner. The complexity of the regulation of the biosynthesis, trafficking, and secretion of POMC and its peptides reflects an impressive level of control over many factors involved in the ultimate role of POMC-expressing cells, that is, to produce a range of different biologically active peptide hormones ready for action when signaled by the body. From the discovery of POMC as the precursor to adrenocorticotropic hormone (ACTH) and β-lipotropin in the late 1970s to our current knowledge, the understanding of POMC physiology remains a monumental body of work that has provided insight into many aspects of molecular endocrinology. In this article, we describe the intracellular trafficking of POMC in endocrine cells, its sorting into dense-core secretory granules and transport of these granules to the RSP. Additionally, we review the enzymes involved in the maturation of POMC to its various peptides and the mechanisms involved in the differential processing of POMC in different cell types. Finally, we highlight studies pertaining to the regulation of ACTH secretion in the anterior and intermediate pituitary and POMC neurons of the hypothalamus.
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Affiliation(s)
- Niamh X Cawley
- Section on Cellular NeurobiologyEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Zhaojin Li
- Section on Cellular NeurobiologyEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Y Peng Loh
- Section on Cellular NeurobiologyEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
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Shi J, Lee S, Uyeda M, Tanjaya J, Kim JK, Pan HC, Reese P, Stodieck L, Lin A, Ting K, Kwak JH, Soo C. Guidelines for Dual Energy X-Ray Absorptiometry Analysis of Trabecular Bone-Rich Regions in Mice: Improved Precision, Accuracy, and Sensitivity for Assessing Longitudinal Bone Changes. Tissue Eng Part C Methods 2016; 22:451-63. [PMID: 26956416 DOI: 10.1089/ten.tec.2015.0383] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Trabecular bone is frequently studied in osteoporosis research because changes in trabecular bone are the most common cause of osteoporotic fractures. Dual energy X-ray absorptiometry (DXA) analysis specific to trabecular bone-rich regions is crucial to longitudinal osteoporosis research. The purpose of this study is to define a novel method for accurately analyzing trabecular bone-rich regions in mice via DXA. This method will be utilized to analyze scans obtained from the International Space Station in an upcoming study of microgravity-induced bone loss. Thirty 12-week-old BALB/c mice were studied. The novel method was developed by preanalyzing trabecular bone-rich sites in the distal femur, proximal tibia, and lumbar vertebrae via high-resolution X-ray imaging followed by DXA and micro-computed tomography (micro-CT) analyses. The key DXA steps described by the novel method were (1) proper mouse positioning, (2) region of interest (ROI) sizing, and (3) ROI positioning. The precision of the new method was assessed by reliability tests and a 14-week longitudinal study. The bone mineral content (BMC) data from DXA was then compared to the BMC data from micro-CT to assess accuracy. Bone mineral density (BMD) intra-class correlation coefficients of the new method ranging from 0.743 to 0.945 and Levene's test showing that there was significantly lower variances of data generated by new method both verified its consistency. By new method, a Bland-Altman plot displayed good agreement between DXA BMC and micro-CT BMC for all sites and they were strongly correlated at the distal femur and proximal tibia (r=0.846, p<0.01; r=0.879, p<0.01, respectively). The results suggest that the novel method for site-specific analysis of trabecular bone-rich regions in mice via DXA yields more precise, accurate, and repeatable BMD measurements than the conventional method.
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Affiliation(s)
- Jiayu Shi
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Soonchul Lee
- 2 Department of Orthopedic Surgery, CHA Bundang Medical Center, CHA University , School of Medicine, Gyeonggi-do, Republic of Korea.,3 Department of Orthopedic Surgery and the Orthopedic Hospital Research Center, University of California , Los Angeles, Los Angeles, California
| | - Michael Uyeda
- 3 Department of Orthopedic Surgery and the Orthopedic Hospital Research Center, University of California , Los Angeles, Los Angeles, California.,4 Division of Plastic and Reconstructive Surgery, Department of Surgery, David Geffen School of Medicine, University of California , Los Angeles, Los Angeles, California
| | - Justine Tanjaya
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Jong Kil Kim
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Hsin Chuan Pan
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Patricia Reese
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Louis Stodieck
- 5 Aerospace Engineering Sciences, University of Colorado , Boulder, Colorado
| | - Andy Lin
- 6 Institute for Digital Research and Education Statistical Consulting Group, University of California , Los Angeles, Los Angeles, California
| | - Kang Ting
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California.,3 Department of Orthopedic Surgery and the Orthopedic Hospital Research Center, University of California , Los Angeles, Los Angeles, California
| | - Jin Hee Kwak
- 1 Division of Growth and Development and Section of Orthodontics, School of Dentistry, University of California , Los Angeles, Los Angeles, California
| | - Chia Soo
- 3 Department of Orthopedic Surgery and the Orthopedic Hospital Research Center, University of California , Los Angeles, Los Angeles, California.,4 Division of Plastic and Reconstructive Surgery, Department of Surgery, David Geffen School of Medicine, University of California , Los Angeles, Los Angeles, California
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CPE overexpression is correlated with pelvic lymph node metastasis and poor prognosis in patients with early-stage cervical cancer. Arch Gynecol Obstet 2015; 294:333-42. [PMID: 26695643 DOI: 10.1007/s00404-015-3985-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/07/2015] [Indexed: 12/16/2022]
Abstract
PURPOSE Elevated carboxypeptidase E (CPE) levels play crucial roles in tumorigenesis and metastasis. This study investigated the expression and clinicopathological significance of CPE in early-stage cervical cancer. METHODS Elevated carboxypeptidase E expression was analyzed using quantitative polymerase chain reaction and western blotting in normal cervical tissue, cervical cancer cell lines, and in cervical cancer tissues and adjacent noncancerous tissues (ANTs) from the same patient. Immunohistochemistry (IHC) was used to examine CPE expression in tissue samples from 112 patients with early-stage cervical cancer (FIGO stages Ia2-IIa2), 60 patients with cervical intraepithelial neoplasia, and 19 patients with normal cervical tissues (NCTs). Associations between CPE expression and prognostic and diagnostic factors were evaluated statistically. RESULTS CPE expression was significantly higher in cervical cancer cell lines and tissues than in normal tissues and ANTs. Semi-quantitative analysis of IHC indicated that CPE gradually increased from CIN I to cervical cancer, but was absent in NCTs. CPE expression was seen in 40.2 % (45/112) of the cervical cancer samples. CPE expression was significantly associated with FIGO stage (P = 0.003), tumor size (P = 0.012), stromal invasion (P < 0.001), lymphovascular space invasion (P = 0.016), parametrial infiltration (P = 0.027), vaginal involvement (P = 0.007), postoperative adjuvant therapy (P = 0.024), recurrence (P < 0.001), survival (P < 0.001), and pelvic lymph node metastasis (PLNM) (P < 0.001), and it was significantly higher in tissues from patients with PLNM than without PLNM. Logistic regression analysis identified high-level CPE expression as an independent risk factor for PLNM (P = 0.001). Patients with higher CPE expression had shorter overall survival duration than patients with lower CPE expression. Univariate and multivariate Cox-regression analyses suggested that high-level CPE expression is an independent prognostic factor for overall survival in early-stage cervical cancer. CONCLUSIONS High-level CPE expression was associated with a poor prognosis in early-stage cervical cancer. CPE may serve as a biomarker for predicting PLNM and survival in these patients.
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Alsters SIM, Goldstone AP, Buxton JL, Zekavati A, Sosinsky A, Yiorkas AM, Holder S, Klaber RE, Bridges N, van Haelst MM, le Roux CW, Walley AJ, Walters RG, Mueller M, Blakemore AIF. Truncating Homozygous Mutation of Carboxypeptidase E (CPE) in a Morbidly Obese Female with Type 2 Diabetes Mellitus, Intellectual Disability and Hypogonadotrophic Hypogonadism. PLoS One 2015; 10:e0131417. [PMID: 26120850 PMCID: PMC4485893 DOI: 10.1371/journal.pone.0131417] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 06/02/2015] [Indexed: 01/25/2023] Open
Abstract
Carboxypeptidase E is a peptide processing enzyme, involved in cleaving numerous peptide precursors, including neuropeptides and hormones involved in appetite control and glucose metabolism. Exome sequencing of a morbidly obese female from a consanguineous family revealed homozygosity for a truncating mutation of the CPE gene (c.76_98del; p.E26RfsX68). Analysis detected no CPE expression in whole blood-derived RNA from the proband, consistent with nonsense-mediated decay. The morbid obesity, intellectual disability, abnormal glucose homeostasis and hypogonadotrophic hypogonadism seen in this individual recapitulates phenotypes in the previously described fat/fat and Cpe knockout mouse models, evidencing the importance of this peptide/hormone-processing enzyme in regulating body weight, metabolism, and brain and reproductive function in humans.
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Affiliation(s)
- Suzanne I. M. Alsters
- Section of Investigative Medicine, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Anthony P. Goldstone
- Imperial Centre for Endocrinology, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom
- Centre for Neuropsychopharmacology and Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Department of Medicine, Imperial College London, Hammersmith Hospital, London, United Kingdom
- Metabolic and Molecular Imaging Group, MRC Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, London, United Kingdom
- * E-mail: (AG); (AB)
| | - Jessica L. Buxton
- Section of Investigative Medicine, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
- Centre for Cardiovascular Genetics, UCL Institute of Cardiovascular Science, London, United Kingdom
| | - Anna Zekavati
- NIHR Imperial BRC Genomics Facility, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Alona Sosinsky
- NIHR Imperial BRC Genomics Facility, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Andrianos M. Yiorkas
- Section of Investigative Medicine, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
| | - Susan Holder
- NW Thames Regional Genetics Service, Kennedy Galton Centre, North West London Hospitals NHS Trust, Northwick Park Hospital, Harrow, United Kingdom
| | - Robert E. Klaber
- Department of Paediatrics, Imperial College Healthcare NHS Trust, St Mary's Hospital, London, United Kingdom
| | - Nicola Bridges
- Department of Paediatric Endocrinology, Chelsea and Westminster Hospital, London, United Kingdom
| | - Mieke M. van Haelst
- Department of Medical Genetics, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Carel W. le Roux
- Section of Investigative Medicine, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
- Diabetes Complications Research Centre, Conway Institute, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Andrew J. Walley
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Robin G. Walters
- Clinical Trial Service Unit and Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Michael Mueller
- NIHR Imperial BRC Genomics Facility, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Alexandra I. F. Blakemore
- Section of Investigative Medicine, Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Imperial College London, London, United Kingdom
- * E-mail: (AG); (AB)
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Zou J, Xiong X, Lai B, Sun M, Tu X, Gao X. Glucose metabolic abnormality is associated with defective mineral homeostasis in skeletal disorder mouse model. SCIENCE CHINA-LIFE SCIENCES 2015; 58:359-67. [DOI: 10.1007/s11427-015-4827-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 12/31/2014] [Indexed: 12/17/2022]
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Liu A, Shao C, Jin G, Liu R, Hao J, Shao Z, Liu Q, Hu X. Downregulation of CPE regulates cell proliferation and chemosensitivity in pancreatic cancer. Tumour Biol 2014; 35:12459-65. [PMID: 25374060 DOI: 10.1007/s13277-014-2564-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 08/26/2014] [Indexed: 01/03/2023] Open
Abstract
Pancreatic cancer (PC) is one of the most common cancers worldwide and a leading cause of cancer-related death. Discovering novel targets is a key for its therapy. Carboxypeptidase E (CPE), a subtype of the pro-protein convertases, has been shown to be upregulated in many types of cancer, yet its function in PC remains elusive. The expressions of CPE in PC cell lines and cancer patients were investigated by Western blot and qRT-PCR. In PC cell line BX-pc-3, CPE was downregulated and its effect on cancer cell proliferation, migration, cisplatin chemosensitivity, and in vivo tumor growth was analyzed by Western blot, proliferation assay, invasion assay, and in vivo transplantation, respectively. The expression of nuclear factor-kappaB (NF-κB), a possible downstream target of CPE was examined by Western blot upon CPE regulation in PC cells, and the effects of inhibiting NF-κB on PC cell invasion and proliferation were examined. CPE was significantly upregulated in PC cell lines and tumor tissues. Proliferation and invasion assays indicated that downregulation of CPE inhibited cancer cell growth and migration and increased chemosensitivity to cisplatin. Inoculation of small interfering RNA (siRNA) transfected BX-pc-3 cells into null mice demonstrated that downregulation of CPE prevented tumor growth in vivo. NF-κB was directly regulated by CPE in pancreatic cancer, and siRNA-mediated inhibition of NF-κB exerted similar anti-tumor effect as downregulating CPE. Taken together, our results demonstrate that CPE plays an important role in pancreatic cancer. Inhibition of CPE may serve as a potential target for PC therapeutics.
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Affiliation(s)
- Anan Liu
- Department of Pancreatic Surgery, Changhai Hospital of Second Military Medical University, Shanghai, 200433, China
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Kim HJ, Hong J, Yoon HJ, Yoon YR, Kim SY. Carboxypeptidase E is a novel modulator of RANKL-induced osteoclast differentiation. Mol Cells 2014; 37:685-90. [PMID: 25220258 PMCID: PMC4179137 DOI: 10.14348/molcells.2014.0179] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 07/29/2014] [Accepted: 07/30/2014] [Indexed: 12/03/2022] Open
Abstract
Osteoclasts are large polykaryons that have the unique capacity to degrade bone and are generated by the differentiation of myeloid lineage progenitors. To identify the genes involved in osteoclast development, we performed microarray analysis, and we found that carboxypeptidase E (CPE), a prohormone processing enzyme, was highly upregulated in osteoclasts compared with their precursors, bone marrow-derived macrophages (BMMs). Here, we demonstrate a novel role for CPE in receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation. The overexpression of CPE in BMMs increases the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear osteoclasts and the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are key regulators in osteoclastogenesis. Furthermore, employing CPE knockout mice, we show that CPE deficiency attenuates osteoclast formation. Together, our data suggest that CPE might be an important modulator of RANKL-induced osteoclast differentiation.
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Affiliation(s)
- Hyun-Ju Kim
- Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, School of Medicine, Kyungpook National University, Daegu 700-422, Korea
- Skeletal Diseases Genome Research Center, Kyungpook National University Hospital, Daegu 700-412, Korea
| | - JungMin Hong
- Skeletal Diseases Genome Research Center, Kyungpook National University Hospital, Daegu 700-412, Korea
| | - Hye-Jin Yoon
- Skeletal Diseases Genome Research Center, Kyungpook National University Hospital, Daegu 700-412, Korea
| | - Young-Ran Yoon
- Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, School of Medicine, Kyungpook National University, Daegu 700-422, Korea
| | - Shin-Yoon Kim
- Skeletal Diseases Genome Research Center, Kyungpook National University Hospital, Daegu 700-412, Korea
- Department of Orthopedic Surgery, School of Medicine, Kyungpook National University, Daegu 700-422, Korea
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Dahm PH, Richards JB, Karmouty-Quintana H, Cromar KR, Sur S, Price RE, Malik F, Spencer CY, Barreno RX, Hashmi SS, Blackburn MR, Haque IU, Johnston RA. Effect of antigen sensitization and challenge on oscillatory mechanics of the lung and pulmonary inflammation in obese carboxypeptidase E-deficient mice. Am J Physiol Regul Integr Comp Physiol 2014; 307:R621-33. [PMID: 25009214 DOI: 10.1152/ajpregu.00205.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Atopic, obese asthmatics exhibit airway obstruction with variable degrees of eosinophilic airway inflammation. We previously reported that mice obese as a result of a genetic deficiency in either leptin (ob/ob mice) or the long isoform of the leptin receptor (db/db mice) exhibit enhanced airway obstruction in the presence of decreased numbers of bronchoalveolar lavage fluid (BALF) eosinophils compared with lean, wild-type mice following antigen (ovalbumin; OVA) sensitization and challenge. To determine whether the genetic modality of obesity induction influences the development of OVA-induced airway obstruction and OVA-induced pulmonary inflammation, we examined indices of these sequelae in mice obese as a result of a genetic deficiency in carboxypeptidase E, an enzyme that processes prohormones and proneuropeptides involved in satiety and energy expenditure (Cpe(fat) mice). Accordingly, Cpe(fat) and lean, wild-type (C57BL/6) mice were sensitized to OVA and then challenged with either aerosolized PBS or OVA. Compared with genotype-matched, OVA-sensitized and PBS-challenged mice, OVA sensitization and challenge elicited airway obstruction and increased BALF eosinophils, macrophages, neutrophils, IL-4, IL-13, IL-18, and chemerin. However, OVA challenge enhanced airway obstruction and pulmonary inflammation in Cpe(fat) compared with wild-type mice. These results demonstrate that OVA sensitization and challenge enhance airway obstruction in obese mice regardless of the genetic basis of obesity, whereas the degree of OVA-induced pulmonary inflammation is dependent on the genetic modality of obesity induction. These results have important implications for animal models of asthma, as modeling the pulmonary phenotypes for subpopulations of atopic, obese asthmatics critically depends on selecting the appropriate mouse model.
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Affiliation(s)
- Paul H Dahm
- Division of Critical Care Medicine, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
| | - Jeremy B Richards
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Harry Karmouty-Quintana
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas
| | - Kevin R Cromar
- Department of Environmental Medicine, New York University School of Medicine, Tuxedo, New York
| | - Sanjiv Sur
- Division of Allergy and Immunology, Department of Internal Medicine, The University of Texas Medical Branch at Galveston School of Medicine, Galveston, Texas
| | - Roger E Price
- Comparative Pathology Laboratory, Center for Comparative Medicine, Baylor College of Medicine, Houston, Texas
| | - Farhan Malik
- Division of Critical Care Medicine, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
| | - Chantal Y Spencer
- Pediatric Pulmonary Section, Department of Pediatrics, Baylor College of Medicine, Houston, Texas; and
| | - Ramon X Barreno
- Division of Critical Care Medicine, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
| | - Syed S Hashmi
- Pediatric Research Center, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
| | - Michael R Blackburn
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, Texas
| | - Ikram U Haque
- Division of Critical Care Medicine, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
| | - Richard A Johnston
- Division of Critical Care Medicine, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas; Pediatric Research Center, Department of Pediatrics, The University of Texas Medical School at Houston, Houston, Texas
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Weight gain in risperidone therapy: investigation of peripheral hypothalamic neurohormone levels in psychotic patients. J Clin Psychopharmacol 2013; 33:608-13. [PMID: 23807284 DOI: 10.1097/jcp.0b013e318297980e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The use of antipsychotic drugs has started a new era in the treatment of psychotic disorders. Nevertheless, they cause complications in the long-term treatment, which is mainly weight gain. In this study, we investigated circulating levels of hypothalamic neuropeptides, which are related to appetite regulation, neuropeptide Y (NPY), α-melanocyte-stimulating hormone (α-MSH), cocaine- and amphetamine-regulated transcript (CART), and leptin, in first-attack psychotic patients who were treated with an atypical antipsychotic drug, risperidone, for 4 weeks. We used a case-control association design to compare the neuropeptides in the control group versus before and after treatment of the patient group. Samples were obtained from psychotic patients who were admitted to the Psychiatry Outpatient Clinics, Gulhane School of Medicine, Ankara, Turkey. When compared with the control group, NPY and α-MSH plasma levels of psychotic patients were severely reduced, and the CART levels were substantially increased when they were first diagnosed (before treatment). However, the patients' body mass index and circulating leptin levels were markedly high after the treatment. Circulating levels of those neurohormones were not significantly changed between before and after treatment of the patients. These data demonstrate that peripheral α-MSH and NPY, although reflecting only secretion from peripheral organs, nevertheless, may provide an insight into the patients sympathetic tone and also suggest change of their appetite regulation. α-Melanocyte-stimulating hormone, NPY, and CART plasma levels may be used as a predictor of weight gain in the early treatment of the patients along with the leptin levels.
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Zhang JH, Zhou D, You J, Tang BS, Li PY, Tang SS. Differential processing of neuropeptide proprotein in human breast adenocarcinoma. J Endocrinol Invest 2013; 36:745-52. [PMID: 23580127 DOI: 10.3275/8935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND The processing of proprotein convertase (PC)-mediated neuropeptide plays a very important role in carcinogenesis and tumor proliferation. AIM To investigate proneuropeptide processing mechanism in tumorigenesis and tumor proliferation. MATERIALS AND METHODS The expression and processing profiles of PC1, carboxypeptidase E (CPE), PC2, GHRH, or neuropeptide Y (NPY) gene and protein level were investigated between 42 human breast tumor tissues and 21 tumor-adjacent normal tissues. RESULTS Gene analyses indicated that the proPC1, CPE, or preproNPY gene had higher expression in the breast tumor tissues, whereas the proPC2 or preproGHRH gene showed lower expression in the tissues. Protein analyses showed that the proPC1, PC1, CPE, GHRH, and preproNPY proteins were upregulated in the tumor tissues, whereas the proPC2, PC2, preproGHRH, and NPY proteins were down-regulated in them. The tissue results were highly corroborated with the serum data from the tumor patients and healthy women. CONCLUSIONS The higher PC1 and CPE expressions as well as the transformation of more proGHRH into active GHRH peptide suggest stronger PC1/CPE-mediated neuropeptide processing in the tumor, whereas the lower PC2 expression as well as the transformation of less proNPY into active NPY peptide suggests a weak PC2-mediated processing in it. The alterations of the convertase expressions and processing show that there is a differential proprotein processing system in the tumor, which leads to the abnormal distributions of species, ratio, and concentration of (pro)peptide(s) in the microenvironment of cells. The latter may contribute to cancer progression.
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Affiliation(s)
- J H Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Courses, Guangdong Pharmaceutical University, Guangzhou, China
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Liang XH, Li LL, Wu GG, Xie YC, Zhang GX, Chen W, Yang HF, Liu QL, Li WH, He WG, Huang YN, Zeng XC. Upregulation of CPE promotes cell proliferation and tumorigenicity in colorectal cancer. BMC Cancer 2013; 13:412. [PMID: 24006921 PMCID: PMC3844403 DOI: 10.1186/1471-2407-13-412] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 08/30/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Colorectal cancer (CRC) is one of the most common cancers worldwide and a leading cause of cancer related death. Although the mortality rate of CRC is decreasing, finding novel targets for its therapy remains urgent. Carboxypeptidase E (CPE), a member of the pro-protein convertases, which are involved in the maturation of protein precursors, has recently been reported as elevated in many types of cancer. However, its role and mechanisms in tumor progression are poorly understood. METHODS In the present study, we investigated expression of CPE in CRC cell lines and tumor tissues using Western blot and real-time qRT-PCR. Plasmids for overexpression and depletion of CPE were constructed and analyzed by Western blot, MTT and colony formation assays and bromodeoxyuridine incorporation assays. The relative expression of p21, p27, and cyclin D1 were analyzed by Real-time qRT-PCR in the indicated cells. RESULTS Our study showed that CPE was significantly upregulated in CRC cell lines and tumor tissues. MTT and colony formation assays indicated that overexpression of CPE enhanced cell growth rates. BrdU incorporation and flow-cytometry assays showed that ectopic expression of CPE increased the S-phase fraction cells. Soft agar assay proved enhanced tumorigenicity activity in CPE over-expressing CRC cells. Further studies of the molecular mechanisms of CPE indicated that is promoted cell proliferation and tumorigenicity through downregulation of p21 and p27, and upregulation of cyclin D1. CONCLUSIONS Taken together, these data suggest that CPE plays an important role in cell cycle regulation and tumorigenicity, and may serve as a potential target for CRC therapeutics.
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Affiliation(s)
- Xing-Hua Liang
- Department of General Surgery, Zengcheng People's Hospital, (BoJi-Affiliated Hospital of Sun Yat-Sen University), Zengcheng 511300, China.
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He JY, Zheng XF, Jiang SD, Chen XD, Jiang LS. Sympathetic neuron can promote osteoblast differentiation through BMP signaling pathway. Cell Signal 2013; 25:1372-8. [DOI: 10.1016/j.cellsig.2013.02.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 02/09/2013] [Indexed: 12/30/2022]
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Abstract
Peptide hormones with a C-terminal amide regulate numerous physiological processes and are associated with many disease states. Consequently, the key enzymes involved in their production, peptidylglycine α-amidating monooxygenase and carboxypeptidase E, have been studied intensively. This review surveys what is known about the enzymes themselves and their cofactors, as well as their substrates and competitive and mechanism-based inhibitors.
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Böhm M, Grässel S. Role of proopiomelanocortin-derived peptides and their receptors in the osteoarticular system: from basic to translational research. Endocr Rev 2012; 33:623-51. [PMID: 22736674 PMCID: PMC3410228 DOI: 10.1210/er.2011-1016] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Proopiomelanocortin (POMC)-derived peptides such as melanocortins and β-endorphin (β-ED) exert their pleiotropic effects via binding to melanocortin receptors (MCR) and opioid receptors (OR). There is now compelling evidence for the existence of a functional POMC system within the osteoarticular system. Accordingly, distinct cell types of the synovial tissue and bone have been identified to generate POMC-derived peptides like β-ED, ACTH, or α-MSH. MCR subtypes, especially MC1R, MC2R (the ACTH receptor), MC3R, and MC4R, but also the μ-OR and δ-OR, have been detected in various cells of the synovium, cartilage, and bone. The respective ligands of these POMC-derived peptide receptors mediate an increasing number of newly recognized biological effects in the osteoarticular system. These include bone mineralization and longitudinal growth, cell proliferation and differentiation, extracellular matrix synthesis, osteoprotection, and immunomodulation. Importantly, bone formation is also regulated by the central melanocortin system via a complex hormonal interplay with other organs and tissues involved in energy metabolism. Among the POMC-derived peptides examined in cell culture systems from osteoarticular tissue and in animal models of experimentally induced arthritis, α-MSH, ACTH, and MC3R-specific agonists appear to have the most promising antiinflammatory actions. The effects of these melanocortin peptides may be exploited in future for the treatment of patients with inflammatory and degenerative joint diseases.
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Affiliation(s)
- Markus Böhm
- Laboratory for Neuroendocrinology of the Skin and Interdisciplinary Endocrinology, Department of Dermatology, University of Münster, Von Esmarch-Strasse 58, D-48149 Münster, Germany.
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Braun TP, Orwoll B, Zhu X, Levasseur PR, Szumowski M, Nguyen MLT, Bouxsein ML, Klein RF, Marks DL. Regulation of lean mass, bone mass, and exercise tolerance by the central melanocortin system. PLoS One 2012; 7:e42183. [PMID: 22848742 PMCID: PMC3407101 DOI: 10.1371/journal.pone.0042183] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 07/02/2012] [Indexed: 12/31/2022] Open
Abstract
Signaling via the type 4-melanocortin receptor (MC4R) is an important determinant of body weight in mice and humans, where loss of function mutations lead to significant obesity. Humans with mutations in the MC4R experience an increase in lean mass. However, the simultaneous accrual of fat mass in such individuals may contribute to this effect via mechanical loading. We therefore examined the relationship of fat mass and lean mass in mice lacking the type-4 melanocortin receptor (MC4RKO). We demonstrate that MC4RKO mice display increased lean body mass. Further, this is not dependent on changes in adipose mass, as MC4RKO mice possess more lean body mass than diet-induced obese (DIO) wild type mice with equivalent fat mass. To examine potential sources of the increased lean mass in MC4RKO mice, bone mass and strength were examined in MC4RKO mice. Both parameters increase with age in MC4RKO mice, which likely contributes to increases in lean body mass. We functionally characterized the increased lean mass in MC4RKO mice by examining their capacity for treadmill running. MC4R deficiency results in a decrease in exercise performance. No changes in the ratio of oxidative to glycolytic fibers were seen, however MC4RKO mice demonstrate a significantly reduced heart rate, which may underlie their impaired exercise performance. The reduced exercise capacity we report in the MC4RKO mouse has potential clinical ramifications, as efforts to control body weight in humans with melanocortin deficiency may be ineffective due to poor tolerance for physical activity.
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Affiliation(s)
- Theodore P. Braun
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
- MD/PhD Program, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Benjamin Orwoll
- Department of Pediatrics, Loma Linda University, Loma Linda, California, United States of America
| | - Xinxia Zhu
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Peter R. Levasseur
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Marek Szumowski
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - My Linh T. Nguyen
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Mary L. Bouxsein
- Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Robert F. Klein
- Bone and Mineral Unit, Division of Endocrinology, Diabetes and Clinical Nutrition, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Daniel L. Marks
- Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, Oregon, United States of America
- * E-mail:
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Gene expression profile in bone of diabetes-prone BB/OK rats fed a high-fat diet. GENES AND NUTRITION 2012; 8:99-104. [PMID: 22639302 DOI: 10.1007/s12263-012-0299-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 05/02/2012] [Indexed: 12/13/2022]
Abstract
A high-fat diet (HFD) has been recognized as a risk factor for diseases such as dyslipidemia, atherosclerosis, obesity, and osteoporosis. However, studies analyzing gene expression after HFD in bone are rare. That prompted us to analyze the expression of selected genes in bone of 4-week-old diabetes-prone B(io)B(reeding) rats. Two breeding pairs were fed a HFD (+10 % tallow) or were fed a normal diet (ND; Ssniff R-Z) before mating and afterward during pregnancy. After the birth of progeny, parents continued to be given HFD or ND until the progeny was weaned (3 weeks). Thereafter, offspring were weaned and were fed the same food as their parents up to an age of 4 weeks. Body weight was measured at an age of 4 weeks, and subsequently 13 HFD rats and 13 ND rats were killed and the tibial bone was harvested to analyze the expression of 53 genes in bone. All rats fed HFD were significantly heavier than rats fed ND after 3 and 4 weeks. The diet also influenced the expression of genes in bone. There were significant differences in 20 out of 53 genes studied between rats fed HFD compared with rats fed ND. Four out of 20 had a lower and 17 out of 20 genes a higher expression in HFD rats, but differences in gene expression showed obvious differences between males and females. There were only two genes that were similarly different between males and females: Bmp4 and Atf4. Two genes, Foxg1 and Npy, were inversely expressed in males and females. It seems that the gene expression is differently regulated by diet during pregnancy and later in life between males and females. Nevertheless, it cannot be excluded that HFD also acts as an epigenetic factor in the development of offspring in utero.
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Cawley NX, Wetsel WC, Murthy SRK, Park JJ, Pacak K, Loh YP. New roles of carboxypeptidase E in endocrine and neural function and cancer. Endocr Rev 2012; 33:216-53. [PMID: 22402194 PMCID: PMC3365851 DOI: 10.1210/er.2011-1039] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 01/18/2012] [Indexed: 01/14/2023]
Abstract
Carboxypeptidase E (CPE) or carboxypeptidase H was first discovered in 1982 as an enkephalin-convertase that cleaved a C-terminal basic residue from enkephalin precursors to generate enkephalin. Since then, CPE has been shown to be a multifunctional protein that subserves many essential nonenzymatic roles in the endocrine and nervous systems. Here, we review the phylogeny, structure, and function of CPE in hormone and neuropeptide sorting and vesicle transport for secretion, alternative splicing of the CPE transcript, and single nucleotide polymorphisms in humans. With this and the analysis of mutant and knockout mice, the data collectively support important roles for CPE in the modulation of metabolic and glucose homeostasis, bone remodeling, obesity, fertility, neuroprotection, stress, sexual behavior, mood and emotional responses, learning, and memory. Recently, a splice variant form of CPE has been found to be an inducer of tumor growth and metastasis and a prognostic biomarker for metastasis in endocrine and nonendocrine tumors.
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Affiliation(s)
- Niamh X Cawley
- Section on Cellular Neurobiology, Program on Developmental Neuroscience, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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Lee TK, Murthy SRK, Cawley NX, Dhanvantari S, Hewitt SM, Lou H, Lau T, Ma S, Huynh T, Wesley RA, Ng IO, Pacak K, Poon RT, Loh YP. An N-terminal truncated carboxypeptidase E splice isoform induces tumor growth and is a biomarker for predicting future metastasis in human cancers. J Clin Invest 2011; 121:880-92. [PMID: 21285511 DOI: 10.1172/jci40433] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 12/01/2010] [Indexed: 11/17/2022] Open
Abstract
Metastasis is a major cause of mortality in cancer patients. However, the mechanisms governing the metastatic process remain elusive, and few accurate biomarkers exist for predicting whether metastasis will occur, something that would be invaluable for guiding therapy. We report here that the carboxypeptidase E gene (CPE) is alternatively spliced in human tumors to yield an N-terminal truncated protein (CPE-ΔN) that drives metastasis. mRNA encoding CPE-ΔN was found to be elevated in human metastatic colon, breast, and hepatocellular carcinoma (HCC) cell lines. In HCC cells, cytosolic CPE-ΔN was translocated to the nucleus and interacted with histone deacetylase 1/2 to upregulate expression of the gene encoding neural precursor cell expressed, developmentally downregulated gene 9 (Nedd9)--which has been shown to promote melanoma metastasis. Nedd9 upregulation resulted in enhanced in vitro proliferation and invasion. Quantification of mRNA encoding CPE-ΔN in HCC patient samples predicted intrahepatic metastasis with high sensitivity and specificity, independent of cancer stage. Similarly, high CPE-ΔN mRNA copy numbers in resected pheochromocytomas/paragangliomas (PHEOs/PGLs), rare neuroendocrine tumors, accurately predicted future metastasis or recurrence. Thus, CPE-ΔN induces tumor metastasis and should be investigated as a potentially powerful biomarker for predicting future metastasis and recurrence in HCC and PHEO/PGL patients.
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Affiliation(s)
- Terence K Lee
- Department of Surgery, University of Hong Kong, Pokfulam, Hong Kong, China
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Carboxypeptidase E: elevated expression correlated with tumor growth and metastasis in pheochromocytomas and other cancers. Cell Mol Neurobiol 2011; 30:1377-81. [PMID: 21061162 DOI: 10.1007/s10571-010-9592-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 09/02/2010] [Indexed: 12/20/2022]
Abstract
Expression of carboxypeptidase E (CPE), a prohormone processing enzyme in different cancer types, was analyzed from data in the GEO profile database (http://www.ncbi.nlm.nih.gov/geo/) and experimentally in pheochromocytomas. Analysis of microarray data demonstrated that significantly elevated levels of CPE mRNA was found in many metastatic non-endocrine cancers: cervical, colon rectal, renal cancers, Ewing sarcomas (bone cancer), and various types of astrocytomas and oligodendrogliomas, whereas expression of CPE mRNA was virtually absent in their respective counterpart normal tissues. Moreover, there was higher CPE mRNA expression in cells from the metastatic tumor compared to those from the primary tumor in colorectal cancer. Elevated CPE mRNA expression was found in neuroendocrine tumors in lung and pituitary adenomas, although the significance is unclear since endocrine and neuroendocrine cells normally express CPE. However, studies of neuroendocrine tumors, pheochromocytomas, revealed expression of not only wild-type CPE, but a variant which was correlated with tumor behavior. Extremely high CPE mRNA copy numbers of the variant were found in very large or invasive tumors, both of which usually indicate poor prognosis. Thus, collectively the data suggest that CPE may play a role in promoting tumor growth and invasion. CPE could potentially serve as a diagnostic and prognostic biomarker for metastasis in different cancer types.
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