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Zhang Q, Lee CL, Yang T, Li J, Zeng Q, Liu X, Liu Z, Ruan D, Li Z, Kan AS, Cheung KW, Mak AS, Ng VW, Zhao H, Fan X, Duan YG, Zhong L, Chen M, Du M, Li RH, Liu P, Ng EH, Yeung WS, Gao Y, Yao Y, Chiu PC. Adrenomedullin has a pivotal role in trophoblast differentiation: A promising nanotechnology-based therapeutic target for early-onset preeclampsia. SCIENCE ADVANCES 2023; 9:eadi4777. [PMID: 37922358 PMCID: PMC10624351 DOI: 10.1126/sciadv.adi4777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 10/03/2023] [Indexed: 11/05/2023]
Abstract
Early-onset preeclampsia (EOPE) is a severe pregnancy complication associated with defective trophoblast differentiation and functions at implantation, but manifestation of its phenotypes is in late pregnancy. There is no reliable method for early prediction and treatment of EOPE. Adrenomedullin (ADM) is an abundant placental peptide in early pregnancy. Integrated single-cell sequencing and spatial transcriptomics confirm a high ADM expression in the human villous cytotrophoblast and syncytiotrophoblast. The levels of ADM in chorionic villi and serum were lower in first-trimester pregnant women who later developed EOPE than those with normotensive pregnancy. ADM stimulates differentiation of trophoblast stem cells and trophoblast organoids in vitro. In pregnant mice, placenta-specific ADM suppression led to EOPE-like phenotypes. The EOPE-like phenotypes in a mouse PE model were reduced by a placenta-specific nanoparticle-based forced expression of ADM. Our study reveals the roles of trophoblastic ADM in placental development, EOPE pathogenesis, and its potential clinical uses.
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Affiliation(s)
- Qingqing Zhang
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Cheuk-Lun Lee
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Tingyu Yang
- BGI-Shenzhen, Shenzhen 518083, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianlin Li
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Qunxiong Zeng
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Xiaofeng Liu
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Zhongzhen Liu
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Engineering Laboratory for Birth Defects Screening, Shenzhen, China
| | - Degong Ruan
- Stem Cell and Regenerative Medicine Consortium, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Zhuoxuan Li
- Stem Cell and Regenerative Medicine Consortium, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Anita S. Y. Kan
- Department of Obstetrics and Gynaecology, Queen Mary Hospital, Hong Kong, China
| | - Ka-Wang Cheung
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Annisa S. L. Mak
- Department of Obstetrics and Gynaecology, Queen Elizabeth Hospital, Hong Kong, China
| | - Vivian W. Y. Ng
- Department of Obstetrics and Gynaecology, Queen Mary Hospital, Hong Kong, China
| | - Huashan Zhao
- Center for Energy Metabolism and Reproduction, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Xiujun Fan
- Center for Energy Metabolism and Reproduction, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yong-Gang Duan
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Liuying Zhong
- Department of Obstetrics and Gynaecology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Min Chen
- Department of Prenatal Diagnosis and Fetal Medicine, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Meirong Du
- NHC Key Lab of Reproduction Regulation (Shanghai Institute of Planned Parenthood Research), Hospital of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, China
| | - Raymond H. W. Li
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Pengtao Liu
- Stem Cell and Regenerative Medicine Consortium, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Ernest H. Y. Ng
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - William S. B. Yeung
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Ya Gao
- BGI-Shenzhen, Shenzhen 518083, China
- Shenzhen Engineering Laboratory for Birth Defects Screening, Shenzhen, China
| | - Yuanqing Yao
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Philip C. N. Chiu
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Shenzhen Key Laboratory of Fertility Regulation, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
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Dou W, Xie J, Chen J, Zhou J, Xu Z, Wang Z, Zhu Q. Overexpression of adrenomedullin (ADM) alleviates the senescence of human dental pulp stem cells by regulating the miR-152/CCNA2 pathway. Cell Cycle 2023; 22:565-579. [PMID: 36310381 PMCID: PMC9928452 DOI: 10.1080/15384101.2022.2135621] [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] [Indexed: 11/03/2022] Open
Abstract
The limitation of human dental pulp stem cells (DPSCs), which have potential application value in regenerative medicine, is that they are prone to age in vitro. Studies have shown adrenomedullin (ADM) is believed to promote the proliferation of human DPSCs, but whether it can also affect aging remains to be investigated. A lentivirus vector was used to construct human DPSCs overexpressing ADM. Senescence tests were carried out on cells of the 7th and 15th passage. Transcriptome analysis was conducted to analyze microRNA expression regulation changes after human DPSCs overexpressed ADM. H2O2 induced the aging model of human DPSCs, and we examined the mechanism of recovery of aging through transfection experiments with miR-152 mimic, pCDH-CCNA2, and CCNA2 siRNA. Overexpression of ADM significantly upregulated the G2/M phase ratio of human DPSCs in natural passage culture (P = 0.001) and inhibited the expression of p53 (P = 0.014), P21 WAF1 (P = 0.015), and P16 INK4A (P = 0.001). Decreased ROS accumulation was observed in human DPSCs during long-term natural passage (P = 0.022). Transcriptome analysis showed that miR-152 was significantly upregulated during human DPSC senescence (P = 0.001) and could induce cell senescence by directly targeting CCNA2. Transfection with miR-152 mimic significantly reversed the inhibitory effect of ADM overexpression on p53 (P = 0.006), P21 WAF1 (P = 0.012), and P16 INK4A (P = 0.01) proteins in human DPSCs (H2O2-induced). In contrast, pCDH-CCNA2 weakened the effect of the miR-152 mimic, thus promoting cell proliferation and antiaging. ADM-overexpressing human DPSCs promote cell cycle progression and resist cellular senescence through CCNA2 expression promotion by inhibiting miR-152.
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Affiliation(s)
- Wenxue Dou
- Department of Stomatology, The First Affiliated Hospital of Naval Medical University: Changhai Hospital, Shanghai, China
| | - Jiaye Xie
- Department of Stomatology, Tongren Hospital Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jianan Chen
- Department of Stomatology, The First Affiliated Hospital of Naval Medical University: Changhai Hospital, Shanghai, China
| | - Jiajun Zhou
- Department of Stomatology, Eastern Hepatobiliary Surgery Hospital, Shanghai, China
| | - Zunyue Xu
- Department of Stomatology, Shanghai Songjiang District Central Hospital, Shanghai, China
| | - Zheng Wang
- Department of Stomatology, Tongren Hospital Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Qiang Zhu
- Department of Stomatology, The First Affiliated Hospital of Naval Medical University: Changhai Hospital, Shanghai, China,CONTACT Qiang Zhu Department of Stomatology, The First Affiliated Hospital of Naval Medical University: Changhai Hospital, Shanghai200433, China
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Puri S, Kenyon BM, Hamrah P. Immunomodulatory Role of Neuropeptides in the Cornea. Biomedicines 2022; 10:1985. [PMID: 36009532 PMCID: PMC9406019 DOI: 10.3390/biomedicines10081985] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 12/21/2022] Open
Abstract
The transparency of the cornea along with its dense sensory innervation and resident leukocyte populations make it an ideal tissue to study interactions between the nervous and immune systems. The cornea is the most densely innervated tissue of the body and possesses both immune and vascular privilege, in part due to its unique repertoire of resident immune cells. Corneal nerves produce various neuropeptides that have a wide range of functions on immune cells. As research in this area expands, further insights are made into the role of neuropeptides and their immunomodulatory functions in the healthy and diseased cornea. Much remains to be known regarding the details of neuropeptide signaling and how it contributes to pathophysiology, which is likely due to complex interactions among neuropeptides, receptor isoform-specific signaling events, and the inflammatory microenvironment in disease. However, progress in this area has led to an increase in studies that have begun modulating neuropeptide activity for the treatment of corneal diseases with promising results, necessitating the need for a comprehensive review of the literature. This review focuses on the role of neuropeptides in maintaining the homeostasis of the ocular surface, alterations in disease settings, and the possible therapeutic potential of targeting these systems.
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Affiliation(s)
- Sudan Puri
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Brendan M. Kenyon
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
- Departments of Immunology and Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
- Cornea Service, Tufts New England Eye Center, Boston, MA 02111, USA
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Martínez-Herrero S, Martínez A. Adrenomedullin: Not Just Another Gastrointestinal Peptide. Biomolecules 2022; 12:biom12020156. [PMID: 35204657 PMCID: PMC8961556 DOI: 10.3390/biom12020156] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/14/2022] [Accepted: 01/15/2022] [Indexed: 12/11/2022] Open
Abstract
Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are two bioactive peptides derived from the same precursor with several biological functions including vasodilation, angiogenesis, or anti-inflammation, among others. AM and PAMP are widely expressed throughout the gastrointestinal (GI) tract where they behave as GI hormones, regulating numerous physiological processes such as gastric emptying, gastric acid release, insulin secretion, bowel movements, or intestinal barrier function. Furthermore, it has been recently demonstrated that AM/PAMP have an impact on gut microbiome composition, inhibiting the growth of bacteria related with disease and increasing the number of beneficial bacteria such as Lactobacillus or Bifidobacterium. Due to their wide functions in the GI tract, AM and PAMP are involved in several digestive pathologies such as peptic ulcer, diabetes, colon cancer, or inflammatory bowel disease (IBD). AM is a key protective factor in IBD onset and development, as it regulates cytokine production in the intestinal mucosa, improves vascular and lymphatic regeneration and function and mucosal epithelial repair, and promotes a beneficial gut microbiome composition. AM and PAMP are relevant GI hormones that can be targeted to develop novel therapeutic agents for IBD, other GI disorders, or microbiome-related pathologies.
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Martínez-Herrero S, Martínez A. Adrenomedullin regulates intestinal physiology and pathophysiology. Domest Anim Endocrinol 2016; 56 Suppl:S66-83. [PMID: 27345325 DOI: 10.1016/j.domaniend.2016.02.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 02/08/2023]
Abstract
Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are 2 biologically active peptides produced by the same gene, ADM, with ubiquitous distribution and many physiological functions. Adrenomedullin is composed of 52 amino acids, has an internal molecular ring composed by 6 amino acids and a disulfide bond, and shares structural similarities with calcitonin gene-related peptide, amylin, and intermedin. The AM receptor consists of a 7-transmembrane domain protein called calcitonin receptor-like receptor in combination with a single transmembrane domain protein known as receptor activity-modifying protein. Using morphologic techniques, it has been shown that AM and PAMP are expressed throughout the gastrointestinal tract, being specially abundant in the neuroendocrine cells of the gastrointestinal mucosa; in the enterochromaffin-like and chief cells of the gastric fundus; and in the submucosa of the duodenum, ileum, and colon. This wide distribution in the gastrointestinal tract suggests that AM and PAMP may act as gut hormones regulating many physiological and pathologic conditions. To date, it has been proven that AM and PAMP act as autocrine/paracrine growth factors in the gastrointestinal epithelium, play key roles in the protection of gastric mucosa from various kinds of injury, and accelerate healing in diseases such as gastric ulcer and inflammatory bowel diseases. In addition, both peptides are potent inhibitors of gastric acid secretion and gastric emptying; they regulate the active transport of sugars in the intestine, regulate water and ion transport in the colon, modulate colonic bowel movements and small-intestine motility, improve endothelial barrier function, and stabilize circulatory function during gastrointestinal inflammation. Furthermore, AM and PAMP are antimicrobial peptides, and they contribute to the mucosal host defense system by regulating gut microbiota. To get a formal demonstration of the effects that endogenous AM and PAMP may have in gut microbiota, we developed an inducible knockout of the ADM gene. Using this model, we have shown, for the first time, that lack of AM/PAMP leads to changes in gut microbiota composition in mice. Further studies are needed to investigate whether this lack of AM/PAMP may have an impact in the development and/or progression of intestinal diseases through their effect on microbiota composition.
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Affiliation(s)
- S Martínez-Herrero
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, La Rioja 26006, Spain
| | - A Martínez
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, La Rioja 26006, Spain.
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Larráyoz IM, Martínez-Herrero S, García-Sanmartín J, Ochoa-Callejero L, Martínez A. Adrenomedullin and tumour microenvironment. J Transl Med 2014; 12:339. [PMID: 25475159 PMCID: PMC4272513 DOI: 10.1186/s12967-014-0339-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 11/21/2014] [Indexed: 01/03/2023] Open
Abstract
Adrenomedullin (AM) is a regulatory peptide whose involvement in tumour progression is becoming more relevant with recent studies. AM is produced and secreted by the tumour cells but also by numerous stromal cells including macrophages, mast cells, endothelial cells, and vascular smooth muscle cells. Most cancer patients present high levels of circulating AM and in some cases these higher levels correlate with a worst prognosis. In some cases it has been shown that the high AM levels return to normal following surgical removal of the tumour, thus indicating the tumour as the source of this excessive production of AM. Expression of this peptide is a good investment for the tumour cell since AM acts as an autocrine/paracrine growth factor, prevents apoptosis-mediated cell death, increases tumour cell motility and metastasis, induces angiogenesis, and blocks immunosurveillance by inhibiting the immune system. In addition, AM expression gets rapidly activated by hypoxia through a HIF-1α mediated mechanism, thus characterizing AM as a major survival factor for tumour cells. Accordingly, a number of studies have shown that inhibition of this peptide or its receptors results in a significant reduction in tumour progression. In conclusion, AM is a great target for drug development and new drugs interfering with this system are being developed.
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Affiliation(s)
- Ignacio M Larráyoz
- Oncology Area, Center for Biomedical Research of La Rioja CIBIR, C/Piqueras 98, Logroño, 26006, Spain.
| | - Sonia Martínez-Herrero
- Oncology Area, Center for Biomedical Research of La Rioja CIBIR, C/Piqueras 98, Logroño, 26006, Spain.
| | - Josune García-Sanmartín
- Oncology Area, Center for Biomedical Research of La Rioja CIBIR, C/Piqueras 98, Logroño, 26006, Spain.
| | - Laura Ochoa-Callejero
- Oncology Area, Center for Biomedical Research of La Rioja CIBIR, C/Piqueras 98, Logroño, 26006, Spain.
| | - Alfredo Martínez
- Oncology Area, Center for Biomedical Research of La Rioja CIBIR, C/Piqueras 98, Logroño, 26006, Spain.
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Martínez-Herrero S, Larráyoz IM, Ochoa-Callejero L, García-Sanmartín J, Martínez A. Adrenomedullin as a growth and cell fate regulatory factor for adult neural stem cells. Stem Cells Int 2012; 2012:804717. [PMID: 23049570 PMCID: PMC3462413 DOI: 10.1155/2012/804717] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 08/16/2012] [Accepted: 08/21/2012] [Indexed: 01/10/2023] Open
Abstract
The use of stem cells as a strategy for tissue repair and regeneration is one of the biomedical research areas that has attracted more interest in the past few years. Despite the classic belief that the central nervous system (CNS) was immutable, now it is well known that cell turnover occurs in the mature CNS. Postnatal neurogenesis is subjected to tight regulation by many growth factors, cell signals, and transcription factors. An emerging molecule involved in this process is adrenomedullin (AM). AM, a 52-amino acid peptide which exerts a plethora of physiological functions, acts as a growth and cell fate regulatory factor for adult neural stem and progenitor cells. AM regulates the proliferation rate and the differentiation into neurons, astrocytes, and oligodendrocytes of stem/progenitor cells, probably through the PI3K/Akt pathway. The active peptides derived from the AM gene are able to regulate the cytoskeleton dynamics, which is extremely important for mature neural cell morphogenesis. In addition, a defective cytoskeleton may impair cell cycle and migration, so AM may contribute to neural stem cell growth regulation by allowing cells to pass through mitosis. Regulation of AM levels may contribute to program stem cells for their use in medical therapies.
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Affiliation(s)
| | - Ignacio M. Larráyoz
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain
| | - Laura Ochoa-Callejero
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain
| | | | - Alfredo Martínez
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain
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Wong PF, O WS, Tang F. An ontogenic study of adrenomedullin gene expression in the rat lung, adrenal, kidney, and heart. Endocrine 2012; 41:256-65. [PMID: 22042486 DOI: 10.1007/s12020-011-9552-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 10/13/2011] [Indexed: 10/15/2022]
Abstract
In this study, the gene expression of adrenomedullin (Adm) in the peripheral tissues which include lung, adrenal, kidney, and heart during development was investigated in the rat. The preproadrenomedullin (preproAdm) mRNA and mRNAs of its related receptor components, calcitonin receptor-like receptor (Crlr), and receptor activity-modifying proteins (Ramp1, 2 and 3) of the lung, adrenal, kidney, and heart were measured by real-time RT-PCR and the ADM peptide measured by radioimmunoassay in 1-, 7-, 21-day-old rats and the adult rats. From day 1 to 21, preproAdm mRNA levels increased with age in the lung, the kidney, and the heart but decreased with age in the adrenal. ADM levels, however, increased with age in the lung but decreased with age in the kidney, the adrenal, and the heart. The preproAdm levels in the lung, in the kidney, and in the adrenal all increased in the adult rat. ADM peptide levels, however, decreased in the adult rat. Crlr and Ramp2 gene expression increased with age in the lung, in the kidney, and in the heart but decreased with age in the adrenal in the prepubertal rats. The results indicate that the levels of preproAdm mRNA, ADM peptide and its receptor component mRNAs in different tissues followed different patterns of changes during development.
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Affiliation(s)
- P F Wong
- Department of Physiology, LKS Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
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Adrenomedullin is expressed during rodent dental tissue development and promotes cell growth and mineralization. Biol Cell 2010; 102:145-57. [PMID: 19828015 DOI: 10.1042/bc20090122] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION ADM (adrenomedullin) has pleiotropic effects, including regulation of inflammation, infection, angiogenesis, mineralized-tissue formation and development. Recently, we demonstrated up-regulation of the ADM transcript in diseased pulpal tissue while the protein is sequestered within the dentine extracellular matrix during dentinogenesis. The present study aimed to characterize ADM localization during rodent dental tissue development and determine its potential effects on dental cells. Finally, we sought to profile ADM transcript levels in adult organs and tissues to compare its expression in teeth relative to other tissues. RESULTS Immunohistochemical analysis of developmental rat oral tissues indicated that, at E16 (embryonic day 16), ADM was present in dental epithelium and, by E18, ADM localized to the dental papilla and inner and outer dental epithelia. By E20, ADM was detected in secretory odontoblasts and ameloblasts and exhibited a similar expression profile to that of the key dentinogenesis signalling molecule, TGF-beta1 (transforming growth factor-beta1). Cell growth analysis in the dental MDPC-23, OD-21 and control 3T3 cell lines exposed to ADM (range 10(-15)-10(-7) M) together with EDTA-extracted DMPs (dentine matrix proteins) (range 0.00001-1000 mg/ml) containing comparable concentrations of ADM demonstrated that ADM stimulated a biphasic response in dental cell growth, comparable with that of DMPs, with peak stimulation observed at approximately 10(-11) M. For mineralization analysis, cell lines were exposed to combinations of 50 microg/ml ascorbic acid, 10 mM beta-G (beta-glycerophosphate), 10(-8) M DEX (dexamethasone) and ADM (range 10(-15)-10(-7) M). The results demonstrated that ADM could substitute for DEX to stimulate mineralization. Postnatally, multiple tissue expression profiling indicated abundant ADM levels in tongue and pulpal tissues. CONCLUSIONS During oral and dental tissue development ADM initially localizes to epithelial tissue, whereas during later stages it is present in mineralized secreting cells, including odontoblasts. ADM may regulate proliferation and mineralization processes during development, whereas, in adulthood, it may be important for maintaining dental tissue homoeostasis.
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Li Y, Jiang C, Wang X, Zhang Y, Shibahara S, Takahashi K. Adrenomedullin is a novel adipokine: adrenomedullin in adipocytes and adipose tissues. Peptides 2007; 28:1129-43. [PMID: 17433499 DOI: 10.1016/j.peptides.2007.03.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 03/01/2007] [Accepted: 03/01/2007] [Indexed: 01/23/2023]
Abstract
Adrenomedullin (AM) is a multifunctional regulatory peptide that is produced and secreted by various types of cells. The production and the secretion of AM have been demonstrated in cultured adipocytes and adipose tissues. Inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and lipopolysaccharide are strong stimulators for AM expression in adipocytes. Furthermore, AM expression in the adipose tissue is increased in obesity, and plasma concentrations of AM are increased in obese subjects. One possible (patho)physiological role of AM secreted by adipose tissue may be actions against complications of the metabolic syndrome characterized by obesity, type 2 diabetic mellitus and hypertension, via its antioxidant and potent vasodilator effects. These findings indicate that AM is a new member of the adipokine family.
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Affiliation(s)
- Yin Li
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing 100083, PR China
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Eşrefoglu M, Gül M, Dogru MI, Dogru A, Yürekli M. Adrenomedullin fails to reduce cadmium-induced oxidative damage in rat liver. ACTA ACUST UNITED AC 2007; 58:367-74. [PMID: 17267195 DOI: 10.1016/j.etp.2006.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2006] [Accepted: 11/11/2006] [Indexed: 11/21/2022]
Abstract
Recent studies have demonstrated that chronic cadmium administration induces oxidative stress. In the present study, we investigated the possible therapeutic effect of adrenomedullin, a potent antioxidant, in cadmium-induced morphological, ultrastructural and biochemical alterations. Two groups of rats were exposed to 100 ppm of CdCl(2) in drinking water for four weeks. One of these groups received 3000 ng/kg body weight of adrenomedullin (AdM) intraperitoneally during the last week. Hepatic oxidative stress markers were evaluated by changes in the amount of lipid peroxides and changes in the antioxidant enzyme activities, superoxide dismutase (SOD) and glutathione peroxidase (GPx) and glutathione reductase (GSH) levels. Hepatic damage score was significantly higher in Cd-administered rats than those of controls (p<0.005). Cd-induced ultrastructural changes in hepatocytes included focal parenchymal cell necrosis, dilatation of rough endoplasmic reticulum, proliferation of lysosomes and mitochondrial degeneration. Hepatic damage was accompanied by significant increase in tissue MDA level (p<0.05) and significant decrease in tissue GSH level (p<0.05), and SOD and GPx activities (p>0.05, p>0.005, respectively). Adrenomedullin failed to restore the light and electron microscopic, and biochemical changes. We conclude that although we administered a high dose of adrenomedullin, it failed to reduce cadmium-induced hepatic damage probably because of the irreversibility of Cd-induced hepatic injury.
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Affiliation(s)
- Mukaddes Eşrefoglu
- Department of Histology and Embryology, Medical Faculty, Inonu University, Malatya 44280, Turkey.
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Caron K, Hagaman J, Nishikimi T, Kim HS, Smithies O. Adrenomedullin gene expression differences in mice do not affect blood pressure but modulate hypertension-induced pathology in males. Proc Natl Acad Sci U S A 2007; 104:3420-5. [PMID: 17360661 PMCID: PMC1802008 DOI: 10.1073/pnas.0611365104] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Adrenomedullin (AM) is a potent vasodilator peptide in plasma at picomolar levels. Polymorphisms in the human AM gene have been associated with genetic predisposition to diabetic nephropathy and proteinuria with essential hypertension, and numerous studies have demonstrated that endogenous AM plays a role in protecting the heart and kidneys from fibrosis resulting from cardiovascular disease. Elevated plasma levels of AM are associated with pregnancy and sepsis and with cardiovascular stress and hypertension. However, there are no reports of the effects of genetic differences in the expression of the endogenous AM gene and of gender on blood pressure in these circumstances or on the pathological changes accompanying hypertension. To address these questions, we have generated mice having genetically controlled levels of AM mRNA ranging from approximately 50% to approximately 140% of wild-type levels. These modest changes in AM gene expression have no effect on basal blood pressure. Although pregnancy and sepsis increase plasma AM levels, genetically reducing AM production does not affect the transient hypotension that occurs during normal pregnancy or that is induced by treatment with lipopolysaccharide. Nor does the reduction of AM affect chronic hypertension caused by a renin transgene. However, 50% normal expression of AM enhances cardiac hypertrophy and renal damage in male, but not female, mice with a renin transgene. These observations suggest that the effect of gender on the role of AM in counteracting cardiovascular damage in humans merits careful evaluation.
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Affiliation(s)
- Kathleen Caron
- Department of Cell and Molecular Physiology and Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599, USA.
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Gibbons C, Dackor R, Dunworth W, Fritz-Six K, Caron KM. Receptor activity-modifying proteins: RAMPing up adrenomedullin signaling. Mol Endocrinol 2006; 21:783-96. [PMID: 17053041 DOI: 10.1210/me.2006-0156] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Adrenomedullin (AM) is a 52-amino-acid multifunctional peptide that circulates in the plasma in the low picomolar range and can exert a multitude of biological effects through an autocrine/paracrine mode of action. The mechanism by which AM transduces its signal represents a novel and pharmacologically tractable paradigm in G protein-coupled receptor signaling. Since its discovery in 1993, the study of AM has emerged into a new field of research with nearly 1800 publications that rivals the renown of other common factors like angiopoetin (1015 publications) and ghrelin (1550 publications). Despite the tremendous strides made in recent years toward unveiling the biochemical and cellular functions of AM, we are still lagging in our understanding of the essential roles of AM in normal and disease physiology. As discussed in this current review, a concerted effort to combine information from clinical, genomic, biochemical, and genetic mouse model sources can provide a focused view to help define the physiological functions of AM. Specifically, we find that certain conditions, such as pregnancy, cardiovascular disease, and sepsis, are associated with robust and dynamic changes in the expression of AM and AM receptor proteins, which together represent an elegant mechanism for altering the physiological responsiveness or function of AM. Thus, the modulation of AM signaling may be further exploited for therapeutic strategies in the management and treatment of human disease.
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Affiliation(s)
- Carrie Gibbons
- Department of Cell and Molecular Physiology, CB # 7545, 6340B MBRB, 103 Mason Farm Road, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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Kim JY, Yim JH, Cho JH, Kim JH, Ko JH, Kim SM, Park S, Park JH. Adrenomedullin regulates cellular glutathione content via modulation of gamma-glutamate-cysteine ligase catalytic subunit expression. Endocrinology 2006; 147:1357-64. [PMID: 16322067 DOI: 10.1210/en.2005-0895] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adrenomedullin (AM) participates in a wide range of physiological and pathological processes including vasorelaxation, angiogenesis, cancer promotion, and apoptosis. Recently, it has been reported that AM protects a variety of cells against oxidative stress induced by stressors such as hypoxia, ischemia/reperfusion, and hydrogen peroxide through the phosphatidylinositol 3-kinase (PI3K)-dependent pathway. However, the molecular mechanisms underlying the pathway of cell survival against hypoxic injury are largely unknown. In an effort to investigate the survival mechanism against hypoxic injury, we studied the effects of AM on cellular levels of reactive oxygen species, well-known mediators of cell death after oxidative stress, and the mechanism involved in the regulation of reactive oxygen species levels. Here, we show that AM increases gamma-glutamate-cysteine ligase (gamma-GCL) activity under both hypoxic and normoxic conditions, resulting in an up-regulation of cellular glutathione levels to more than 2-fold higher than basal expression. In addition, we demonstrate that AM induces concentration-dependent expression of the catalytic subunit of gamma-GCL (gamma-GCLC) at the mRNA and protein levels through the activation of the gamma-GCLC promoter fragment sequence from -597 to -320. However, when treated with the PI3K inhibitors, the effects of AM on gamma-GCLC expression were completely abrogated, suggesting that a PI3K pathway linked AM with the transcriptional activation of the gamma-GCLC promoter. Taken together, our data suggests that AM participates in the regulation of cellular redox status via glutathione synthesis. These results may explain, in part, the mechanism by which AM protects cells against oxidative stress.
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Affiliation(s)
- Jee-Youn Kim
- Department of Pathology, College of Medicine, Kyung Hee University, Seoul 130-701, Korea
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Czyzyk TA, Ning Y, Hsu MS, Peng B, Mains RE, Eipper BA, Pintar JE. Deletion of peptide amidation enzymatic activity leads to edema and embryonic lethality in the mouse. Dev Biol 2005; 287:301-13. [PMID: 16225857 DOI: 10.1016/j.ydbio.2005.09.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2004] [Revised: 08/04/2005] [Accepted: 09/06/2005] [Indexed: 11/25/2022]
Abstract
Peptidylglycine alpha-amidating monooxygenase (PAM) catalyzes the COOH-terminal amidation of peptide hormones. We previously had found high expression of PAM in several regions of the developing rodent. To determine the function of PAM during mouse embryogenesis, we produced a null mutant of the PAM gene. Homozygous mutants die in utero between e14.5 and e15.5 with severe edema that is likely due to cardiovascular deficits. These defects include thinning of the aorta and carotid arteries and are very similar to those of the recently characterized adrenomedullin (AM) gene KO despite the presence of elevated immunoreactive AM in PAM KO embryos. No peptide amidation activity was detected in PAM mutant embryos, and there was no moderation of the AM-like phenotype that could be expected if any alternative peptide amidation mechanism exists in the mouse. Despite the proposed contribution of amidated peptides to neuronal cell proliferation, no alteration in neuroblast proliferation was observed in homozygous mutant embryos prior to lethality. Mice heterozygous for the mutant PAM allele develop normally and express wildtype levels of several amidated peptides despite having one half the wildtype levels of PAM activity and PAM protein. Nonetheless, both an increase in adiposity and a mild glucose intolerance developed in aged (>10 months) heterozygous mice compared to littermate controls. Ablation of PAM thus demonstrates an essential function for this gene during mouse development, while alterations in PAM activity in the adult may underlie more subtle physiologic effects.
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Affiliation(s)
- Traci A Czyzyk
- Department of Neuroscience and Cell Biology, CABM Rm 326, UMDNJ-Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA
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Ribatti D, Nico B, Spinazzi R, Vacca A, Nussdorfer GG. The role of adrenomedullin in angiogenesis. Peptides 2005; 26:1670-5. [PMID: 16112409 DOI: 10.1016/j.peptides.2005.02.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2004] [Revised: 02/12/2005] [Accepted: 02/15/2005] [Indexed: 01/14/2023]
Abstract
Adrenomedullin (AM) is a 52 amino acid peptide originally isolated from human pheochromocytoma. It was initially demonstrated to have profound effects in vascular cell biology, since AM protects endothelial cells from apoptosis, promotes angiogenesis and affects vascular tone and permeability. This review article summarizes the literature data concerning the relationship between AM and angiogenesis and describes the relationship between vascular endothelial growth factor, hypoxia and AM and tumor angiogenesis. Finally, the role of AM as a potential target of antiangiogenic therapy is discussed.
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Affiliation(s)
- Domenico Ribatti
- Department of Human Anatomy and Histology, Piazza Giulio Cesare, 11, Policlinico, I-70124 Bari, Italy.
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Frede S, Freitag P, Otto T, Heilmaier C, Fandrey J. The Proinflammatory Cytokine Interleukin 1β and Hypoxia Cooperatively Induce the Expression of Adrenomedullin in Ovarian Carcinoma Cells through Hypoxia Inducible Factor 1 Activation. Cancer Res 2005; 65:4690-7. [PMID: 15930287 DOI: 10.1158/0008-5472.can-04-3877] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adrenomedullin (ADM) is a potent hypotensive peptide produced by macrophages and endothelial cells during ischemia and sepsis. The molecular mechanisms that control ADM gene expression in tumor cells are still poorly defined. It is known, however, that hypoxia potently increases ADM expression by activation of the transcription factor complex hypoxia inducible factor 1 (HIF-1). Proinflammatory cytokines produced by tumor invading macrophages likewise activate expression of ADM. Herein, we show that apart from hypoxia, the proinflammatory cytokine interleukin 1beta (IL-1beta) induced the expression of ADM mRNA through activation of HIF-1 under normoxic conditions and enhanced the hypoxia-induced expression in the human ovarian carcinoma cell line OVCAR-3. IL-1beta significantly increased accumulation and nuclear translocation of HIF-1alpha under normoxic conditions and amplified hypoxic HIF-1 activation. IL-1beta treatment affected neither HIF-1alpha mRNA levels nor the hydroxylation status of HIF-1alpha and, thus, stability of the protein. Instead cycloheximide effectively prevented the increase in HIF-1alpha protein, indicating a stimulatory effect of IL-1beta on HIF-1alpha translation. Finally, treatment of HIF-1alpha with short interfering RNA revealed a significant role for HIF-1 in the IL-1beta-dependent stimulation of ADM expression.
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Affiliation(s)
- Stilla Frede
- Institut für Physiologie, Universität Duisburg-Essen, Essen, Germany
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Penchalaneni J, Wimalawansa SJ, Yallampalli C. Adrenomedullin antagonist treatment during early gestation in rats causes fetoplacental growth restriction through apoptosis. Biol Reprod 2004; 71:1475-83. [PMID: 15229133 DOI: 10.1095/biolreprod.104.032086] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Adrenomedullin (AM), a potent vasorelaxant peptide, has been shown to function as an angiogenic and growth factor. The present study investigated whether antagonism of endogenous AM in rats during early gestation results in diminished placental and fetal growth and whether this occurs through induction of apoptosis. Rats on Gestational Day 8 were implanted s.c. with osmotic minipumps delivering 125 and 250 microg rat(-1) day(-1) of AM(22-52) and were killed on Gestational Day 15. In AM(22-52)-treated rats, both placental and fetal weights were dose-dependently inhibited, with 50% reduction in the group receiving 250 microg rat(-1) day(-1). In these animals, fetal resorption sites were also increased. Apoptosis was demonstrated in placenta and uterus by the TUNEL method. Apoptotic changes were more apparent in trophoblast cells in the labyrinth zone of placenta and uterine decidua of AM(22-52)-treated rats when compared with vehicle-control rats. Immunoreactivity to active caspase-3 protein was abundant in the placenta and uterus of the AM(22-52)-treated group. Western blot analysis demonstrated that in homogenates of both the placenta and uterus of AM(22-52)-treated rats, levels of active caspase-9 and -3 as well as of Poly ADP ribose polymerase were significantly increased, whereas levels of Bcl-2 protein decreased, compared with controls. However, no significant treatment-associated changes were observed in Bid, Fas, Fas ligand, p53, and caspase-8 and -10 proteins in either placenta or uterus. Bad protein was undetectable in either tissue. In mitochondrial fractions from both placenta and uterus, the levels of Bax increased with decreases in cytochrome c on AM(22-52) treatment. Conversely, in the cytosol, Bax levels decreased with increases in cytochrome c, demonstrating translocation of Bax from cytosol to mitochondria and release of cytochrome c from mitochondria with AM(22-52) treatment. In conclusion, these findings show that antagonism of AM in rats during early pregnancy caused fetoplacental growth restriction through the activation of mitochondrial apoptotic pathways.
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Affiliation(s)
- Josthna Penchalaneni
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, 301 University Blvd., Galveston, Texas 77555, USA
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Zudaire E, Cuttitta F, Martínez A. Regulation of pancreatic physiology by adrenomedullin and its binding protein. REGULATORY PEPTIDES 2003; 112:121-30. [PMID: 12667633 DOI: 10.1016/s0167-0115(03)00030-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Adrenomedullin (AM) is a 52 amino acid, multifunctional hormone. It is expressed in many tissues of the human body including the pancreas, where it is mainly localized to the periphery of the islets of Langerhans and specifically to the pancreatic polypeptide-expressing cells. The AM receptor, a complex formed by calcitonin receptor-like receptor (CRLR) and receptor activity-modifying proteins (RAMPs), and the recently discovered AM-binding protein, complement factor H (fH), are expressed in the insulin-producing beta-cells. The colocalization of these key elements of the AM system in the endocrine portion of the pancreas implicates AM in the control of both normal and altered pancreatic physiologies. AM inhibits insulin secretion both in vitro (isolated rat islets) and in vivo (oral glucose tolerance test in rats) in a dose-dependent manner. The addition of fH to isolated rat islets produces a further reduction of insulin secretion in the presence of AM. Furthermore, AM is elevated in plasma from patients with pancreatic dysfunctions such as type 1 or type 2 diabetes and insulinoma. Using a diabetic model in rats, we have shown that AM increases circulating glucose levels whereas a blocking monoclonal antibody against AM has the opposite effect and improves postprandial recovery. Such experimental evidence implicates AM as a fundamental factor in maintaining insulin homeostasis and normoglycemia, and suggests the implication of AM as a possible causal agent in diabetes. Further investigation focused on the development of blocking agents for AM could result in new treatments for pancreatic AM-related disorders.
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Affiliation(s)
- E Zudaire
- Department of Cell and Cancer Biology, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, Building 10, Room 13N262, Bethesda, MD 20892, USA
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Belloni AS, Trejter M, Malendowicz LK, Nussdorfer GG. Adrenomedullin stimulates proliferation and inhibits apoptosis of immature rat thymocytes cultured in vitro. Peptides 2003; 24:295-300. [PMID: 12668215 DOI: 10.1016/s0196-9781(03)00038-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Adrenomedullin (AM) is a hypotensive peptide, which derives from the proteolytic cleavage of pro(p)AM, and acts through two subtypes of receptors, named L1-receptor (L1-R) and calcitonin receptor-like receptor (CRLR). CRLR functions as either a calcitonin gene-related peptide (CGRP) receptor or a selective AM receptor depending on which member of a family of receptor-activity-modifying proteins (RAMPs) is expressed: RAMP1 generates CGRP receptors, while RAMP2 and RAMP3 produce AM receptors. Reverse transcription (RT)-polymerase chain reaction (PCR) consistently allowed the detection of pAM and peptidyl-glycine alpha-amidating monooxygenase (the enzyme converting immature AM to the mature peptide) mRNAs in the thymus cortex of immature (10-day-old) rats. Accordingly, radioimmune assay (RIA) measured low but sizeable AM concentrations in this tissue. RT-PCR also demonstrated the presence of the specific mRNAs of L1-R, CRLR and RAMPs. AM (from 10(-9) to 10(-7)M) increased proliferation index and lowered apoptotic index of cultured immature rat thymocytes, and the effects were annulled by the AM receptor antagonist AM(22-52). In conclusion, our study demonstrated that (1) immature rat thymus cortex expresses AM and the AM receptors L1-R and CRLR/RAMP; and (2) AM, acting via AM(22-52)-sensitive receptors, exerts a potent growth promoting effect on immature rat thymus, by enhancing proliferation and lowering apoptotic death of thymocytes. Taken together, these findings could suggest that AM may play a role in the development of immunity.
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Affiliation(s)
- Anna S Belloni
- Department of Human Anatomy and Physiology, Section of Anatomy, University of Padua, Via Gabelli 65, I-35121, Padua, Italy
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