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Ning J, Sala M, Reina J, Kalagiri R, Hunter T, McCullough BS. Histidine Phosphorylation: Protein Kinases and Phosphatases. Int J Mol Sci 2024; 25:7975. [PMID: 39063217 PMCID: PMC11277029 DOI: 10.3390/ijms25147975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 07/09/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Phosphohistidine (pHis) is a reversible protein post-translational modification (PTM) that is currently poorly understood. The P-N bond in pHis is heat and acid-sensitive, making it more challenging to study than the canonical phosphoamino acids pSer, pThr, and pTyr. As advancements in the development of tools to study pHis have been made, the roles of pHis in cells are slowly being revealed. To date, a handful of enzymes responsible for controlling this modification have been identified, including the histidine kinases NME1 and NME2, as well as the phosphohistidine phosphatases PHPT1, LHPP, and PGAM5. These tools have also identified the substrates of these enzymes, granting new insights into previously unknown regulatory mechanisms. Here, we discuss the cellular function of pHis and how it is regulated on known pHis-containing proteins, as well as cellular mechanisms that regulate the activity of the pHis kinases and phosphatases themselves. We further discuss the role of the pHis kinases and phosphatases as potential tumor promoters or suppressors. Finally, we give an overview of various tools and methods currently used to study pHis biology. Given their breadth of functions, unraveling the role of pHis in mammalian systems promises radical new insights into existing and unexplored areas of cell biology.
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Affiliation(s)
- Jia Ning
- Correspondence: (J.N.); (B.S.M.)
| | | | | | | | | | - Brandon S. McCullough
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; (M.S.); (J.R.); (R.K.); (T.H.)
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2
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Bo C, Liu F, Zhang Z, Du Z, Xiu H, Zhang Z, Li M, Zhang C, Jia Q. Simvastatin attenuates silica-induced pulmonary inflammation and fibrosis in rats via the AMPK-NOX pathway. BMC Pulm Med 2024; 24:224. [PMID: 38720270 PMCID: PMC11080310 DOI: 10.1186/s12890-024-03014-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 04/15/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Simvastatin (Sim), a hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been widely used in prevention and treatment of cardiovascular diseases. Studies have suggested that Sim exerts anti-fibrotic effects by interfering fibroblast proliferation and collagen synthesis. This study was to determine whether Sim could alleviate silica-induced pulmonary fibrosis and explore the underlying mechanisms. METHODS The rat model of silicosis was established by the tracheal perfusion method and treated with Sim (5 or 10 mg/kg), AICAR (an AMPK agonist), and apocynin (a NOX inhibitor) for 28 days. Lung tissues were collected for further analyses including pathological histology, inflammatory response, oxidative stress, epithelial mesenchymal transformation (EMT), and the AMPK-NOX pathway. RESULTS Sim significantly reduced silica-induced pulmonary inflammation and fibrosis at 28 days after administration. Sim could reduce the levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α and transforming growth factor-β1 in lung tissues. The expressions of hydroxyproline, α-SMA and vimentin were down-regulated, while E-cad was increased in Sim-treated rats. In addition, NOX4, p22pox, p40phox, p-p47phox/p47phox expressions and ROS levels were all increased, whereas p-AMPK/AMPK was decreased in silica-induced rats. Sim or AICAR treatment could notably reverse the decrease of AMPK activity and increase of NOX activity induced by silica. Apocynin treatment exhibited similar protective effects to Sim, including down-regulating of oxidative stress and inhibition of the EMT process and inflammatory reactions. CONCLUSIONS Sim attenuates silica-induced pulmonary inflammation and fibrosis by downregulating EMT and oxidative stress through the AMPK-NOX pathway.
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Affiliation(s)
- Cunxiang Bo
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Fang Liu
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
- Guangzhou Huaxia Vocational College, Guangzhou, China
| | - Zewen Zhang
- Department of Radiology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Zhongjun Du
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Haidi Xiu
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Zhenling Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Ming Li
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Caiqing Zhang
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
- Pulmonary and Critical Care Medicine, Shandong Province's Second General Hospital (Shandong Province ENT Hospital), Shandong University of Traditional Chinese Medicine, Jinan, Shandong Province, Shandong, China.
| | - Qiang Jia
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China.
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3
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Li SX, Li C, Pang XR, Zhang J, Yu GC, Yeo AJ, Lavin MF, Shao H, Jia Q, Peng C. Metformin Attenuates Silica-Induced Pulmonary Fibrosis by Activating Autophagy via the AMPK-mTOR Signaling Pathway. Front Pharmacol 2021; 12:719589. [PMID: 34434111 PMCID: PMC8381252 DOI: 10.3389/fphar.2021.719589] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022] Open
Abstract
Long-term exposure to crystalline silica particles leads to silicosis characterized by persistent inflammation and progressive fibrosis in the lung. So far, there is no specific treatment to cure the disease other than supportive care. In this study, we examined the effects of metformin, a prescribed drug for type || diabetes on silicosis and explored the possible mechanisms in an established rat silicosis model in vivo, and an in vitro co-cultured model containing human macrophages cells (THP-1) and human bronchial epithelial cells (HBEC). Our results showed that metformin significantly alleviated the inflammation and fibrosis of lung tissues of rats exposed to silica particles. Metformin significantly reduced silica particle-induced inflammatory cytokines including transforming growth factor-β1 (TGF-β1), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in rat lung tissue and HBEC culture supernatant. The protein levels of Vimentin and α-smooth muscle actin (α-SMA) were significantly decreased by metfomin while expression level of E-cadherin (E-Cad) increased. Besides, metformin increased the expression levels of phosphorylated adenosine 5′-monophosphate (AMP)-activated protein kinase (p-AMPK), microtubule-associated protein (MAP) light chain 3B (LC3B) and Beclin1 proteins, and reduced levels of phosphorylated mammalian target of rapamycin (p-mTOR) and p62 proteins in vivo and in vitro. These results suggest that metformin could inhibit silica-induced pulmonary fibrosis by activating autophagy through the AMPK-mTOR pathway.
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Affiliation(s)
- Shu-Xian Li
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Chao Li
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Xin-Ru Pang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Juan Zhang
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Gong-Chang Yu
- Neck-Shoulder and Lumbocrural Pain Hospital of Shandong First Medical University, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Abrey J Yeo
- University of Queensland Centre for Clinical Research (UQCCR), Brisbane, QLD, Australia
| | - Martin F Lavin
- University of Queensland Centre for Clinical Research (UQCCR), Brisbane, QLD, Australia
| | - Hua Shao
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Qiang Jia
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Cheng Peng
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Brisbane, QLD, Australia
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4
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Wang H, Wang Z, Wang Y, Li X, Yang W, Wei S, Shi C, Qiu J, Ni M, Rao J, Cheng F. miRNA-130b-5p promotes hepatic stellate cell activation and the development of liver fibrosis by suppressing SIRT4 expression. J Cell Mol Med 2021; 25:7381-7394. [PMID: 34272822 PMCID: PMC8335697 DOI: 10.1111/jcmm.16766] [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] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/07/2021] [Accepted: 06/15/2021] [Indexed: 12/14/2022] Open
Abstract
Liver fibrosis is a progressive disease accompanied by the deposition of extracellular matrix (ECM). Numerous reports have demonstrated that alterations in the expression of microRNAs (miRNAs) are related to liver disease. However, the effect of individual miRNAs on liver fibrosis has not been studied. Hepatic stellate cells (HSCs), being responsible for producing ECM, exert an important influence on liver fibrosis. Then, microarray analysis of non‐activated and activated HSCs induced by transforming growth factor β1 (TGF‐β1) showed that miR‐130b‐5p expression was strongly up‐regulated during HSC activation. Moreover, the progression of liver fibrosis had a close connection with the expression of miR‐130b‐5p in different liver fibrosis mouse models. Then, we identified that there were specific binding sites between miR‐130b‐5p and the 3′ UTR of Sirtuin 4 (SIRT4) via a luciferase reporter assay. Knockdown of miR‐130b‐5p increased SIRT4 expression and ameliorated liver fibrosis in mice transfected with antagomiR‐130b‐5p oligos. In general, our results suggested that miR‐130b‐5p promoted HSC activation by targeting SIRT4, which participates in the AMPK/TGF‐β/Smad2/3 signalling pathway. Hence, regulating miR‐130b‐5p maybe serve as a crucial therapeutic treatment for hepatic fibrosis.
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Affiliation(s)
- Hao Wang
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Zeng Wang
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Yirui Wang
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Xiangcheng Li
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Wenjie Yang
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Song Wei
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China.,School of Medical, Southeast University, Nanjing, China
| | - Chengyu Shi
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Jiannan Qiu
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Ming Ni
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Jianhua Rao
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
| | - Feng Cheng
- Hepatobiliary/Liver Transplantation Center, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.,Key Laboratory of Liver Transplantation, Chinese Academy of Medical Sciences, Nanjing, China.,Key Laboratory of Living Donor Liver Transplantation, National Health Commission (NHC), Nanjing, China
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Tian S, Yang X, Wang J, Luo J, Guo H. 1,25-(OH) 2D 3 ameliorates renal interstitial fibrosis in UUO rats through the AMPKα/mTOR pathway. J Int Med Res 2021; 49:300060520981360. [PMID: 33530801 PMCID: PMC7871069 DOI: 10.1177/0300060520981360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Objective To investigate the effects of 1,25(OH)2D3 on renal fibrosis associated with the AMP-activated protein kinase (AMPK)α/mechanistic target of rapamycin (mTOR) signalling pathway in a rat model of unilateral ureteral obstruction (UUO). Methods A total of 54 male Sprague Dawley rats were randomly divided into three groups: sham-operation group, UUO group, and UUO plus calcitriol (3 ng/100 g) group. Renal tissue was excised for histological examination by immunohistochemistry and Western blot, and for gene expression analysis using real-time polymerase chain reaction. Results 1,25(OH)2D3 enhanced AMPKα levels, inhibited mTOR levels and slowed the development of interstitial fibrosis in kidney tissue. Compared with the UUO plus calcitriol group, UUO rats demonstrated more severe renal damage characterized by marked tubular atrophy, interstitial fibrosis and significant induction of fibrogenic transforming growth factor-β1 and increased extra-cellular matrix proteins (α-smooth muscle actin and collagen type III), and decreased E-cadherin. Conclusion Treatment with 1,25(OH)2D3 altered the AMPKα/mTOR signalling pathway to suppress excessive fibroblast activation observed in UUO rats. This may serve as a novel mechanism to ameliorate renal dysfunction and fibrotic lesions.
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Affiliation(s)
- Shasha Tian
- Department of Nephrology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Xiaopeng Yang
- Department of Nephrology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Jianwu Wang
- Department of Nephrology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Jing Luo
- Department of Rheumatology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Hui Guo
- Department of Nephrology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China.,Department of Nephrology, Shenzhen Baoan Shiyan People's Hospital, Shenzhen, Guangdong, China
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6
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Adam K, Ning J, Reina J, Hunter T. NME/NM23/NDPK and Histidine Phosphorylation. Int J Mol Sci 2020; 21:E5848. [PMID: 32823988 PMCID: PMC7461546 DOI: 10.3390/ijms21165848] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 12/15/2022] Open
Abstract
The NME (Non-metastatic) family members, also known as NDPKs (nucleoside diphosphate kinases), were originally identified and studied for their nucleoside diphosphate kinase activities. This family of kinases is extremely well conserved through evolution, being found in prokaryotes and eukaryotes, but also diverges enough to create a range of complexity, with homologous members having distinct functions in cells. In addition to nucleoside diphosphate kinase activity, some family members are reported to possess protein-histidine kinase activity, which, because of the lability of phosphohistidine, has been difficult to study due to the experimental challenges and lack of molecular tools. However, over the past few years, new methods to investigate this unstable modification and histidine kinase activity have been reported and scientific interest in this area is growing rapidly. This review presents a global overview of our current knowledge of the NME family and histidine phosphorylation, highlighting the underappreciated protein-histidine kinase activity of NME family members, specifically in human cells. In parallel, information about the structural and functional aspects of the NME family, and the knowns and unknowns of histidine kinase involvement in cell signaling are summarized.
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Affiliation(s)
| | | | | | - Tony Hunter
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; (K.A.); (J.N.); (J.R.)
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7
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Rintz E, Gaffke L, Podlacha M, Brokowska J, Cyske Z, Węgrzyn G, Pierzynowska K. Transcriptomic Changes Related to Cellular Processes with Particular Emphasis on Cell Activation in Lysosomal Storage Diseases from the Group of Mucopolysaccharidoses. Int J Mol Sci 2020; 21:ijms21093194. [PMID: 32366041 PMCID: PMC7246638 DOI: 10.3390/ijms21093194] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/13/2022] Open
Abstract
Although mucopolysaccharidoses (MPS), inherited metabolic diseases from the group of lysosomal storage diseases (LSD), are monogenic disorders, recent studies indicated that their molecular mechanisms are complicated. Storage of glycosaminoglycans (GAGs), arising from a deficiency in one of the enzymes involved in the degradation of these compounds, is the primary cause of each MPS type. However, dysfunctions of various cellular organelles and disturbance of cellular processes have been reported which contribute considerably to pathomechanisms of the disease. Here, we present a complex transcriptomic analysis in which all types and subtypes of MPS were investigated, with special emphasis on genes related to cell activation processes. Complex changes in expression of these genes were found in fibroblasts of all MPS types, with number of transcripts revealing higher or lower levels (relative to control fibroblasts) between 19 and over 50, depending on MPS type. Genes in which expression was significantly affected in most MPS types code for proteins involved in following processes, classified according to Gene Ontology knowledge database: cell activation, cell growth, cell recognition, and cell division. Levels of some transcripts (including CD9, CLU, MME and others) were especially significantly changed (over five times relative to controls). Our results are discussed in the light of molecular pathomechanisms of MPS, indicating that secondary and/or tertiary changes, relative to GAG storage, might significantly modulate cellular dysfunctions and contribute to molecular mechanisms of the disease. This may influence the efficacy of various therapies and suggests why various treatments are not fully effective in improving the complex symptoms of MPS.
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8
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McCallum ML, Pru CA, Smith AR, Kelp NC, Foretz M, Viollet B, Du M, Pru JK. A functional role for AMPK in female fertility and endometrial regeneration. Reproduction 2020; 156:501-513. [PMID: 30328345 DOI: 10.1530/rep-18-0372] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022]
Abstract
Adenosine monophosphate-activated protein kinase (AMPK) is a highly conserved heterotrimeric complex that acts as an intracellular energy sensor. Based on recent observations of AMPK expression in all structures of the female reproductive system, we hypothesized that AMPK is functionally required for maintaining fertility in the female. This hypothesis was tested by conditionally ablating the two catalytic alpha subunits of AMPK, Prkaa1 and Prkaa2, using Pgr-cre mice. After confirming the presence of PRKAA1, PRKAA2 and the active phospho-PRKAA1/2 in the gravid uterus by immunohistochemistry, control (Prkaa1/2 fl/fl ) and double conditional knockout mice (Prkaa1/2 d/d ) were placed into a six-month breeding trial. While the first litter size was comparable between Prkaa1/2 fl/fl and Prkaa1/2 d/d female mice (P = 0.8619), the size of all subsequent litters was dramatically reduced in Prkaa1/2 d/d female mice (P = 0.0015). All Prkaa1/2 d/d female mice experienced premature reproductive senescence or dystocia by the fourth parity. This phenotype manifested despite no difference in estrous cycle length, ovarian histology in young and old nulliparous or multiparous animals, mid-gestation serum progesterone levels or uterine expression of Esr1 or Pgr between Prkaa1/2 fl/fl and Prkaa1/2 d/d female mice suggesting that the hypothalamic-pituitary-ovary axis remained unaffected by PRKAA1/2 deficiency. However, an evaluation of uterine histology from multiparous animals identified extensive endometrial fibrosis and disorganized stromal-glandular architecture indicative of endometritis, a condition that causes subfertility or infertility in most mammals. Interestingly, Prkaa1/2 d/d female mice failed to undergo artificial decidualization. Collectively, these findings suggest that AMPK plays an essential role in endometrial regeneration following parturition and tissue remodeling that accompanies decidualization.
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Affiliation(s)
- Melissa L McCallum
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
| | - Cindy A Pru
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
| | - Andrea R Smith
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
| | - Nicole C Kelp
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
| | - Marc Foretz
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Benoit Viollet
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Min Du
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
| | - James K Pru
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, Washington, USA
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Ma Z, Yuan D, Cheng X, Tuo B, Liu X, Li T. Function of ion transporters in maintaining acid-base homeostasis of the mammary gland and the pathophysiological role in breast cancer. Am J Physiol Regul Integr Comp Physiol 2019; 318:R98-R111. [PMID: 31553634 DOI: 10.1152/ajpregu.00202.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The incidence of breast cancer is increasing year by year, and the pathogenesis is still unclear. Studies have shown that the high metabolism of solid tumors leads to an increase in hypoxia, glycolysis, production of lactic acid and carbonic acid, and extracellular acidification; a harsh microenvironment; and ultimately to tumor cell death. Approximately 50% of locally advanced breast cancers exhibit hypoxia and/or local hypoxia, and acid-base regulatory proteins play an important role in regulating milk secretion and maintaining mammary gland physiological function. Therefore, ion transporters have gradually become a hot topic in mammary gland and breast cancer research. This review focuses on the research progress of ion transporters in mammary glands and breast cancer. We hope to provide new targets for the treatment and prognosis of breast cancer.
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Affiliation(s)
- Zhiyuan Ma
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Dumin Yuan
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Xiaoming Cheng
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Xuemei Liu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Taolang Li
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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10
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Tsogbadrakh B, Ryu H, Ju KD, Lee J, Yun S, Yu KS, Kim HJ, Ahn C, Oh KH. AICAR, an AMPK activator, protects against cisplatin-induced acute kidney injury through the JAK/STAT/SOCS pathway. Biochem Biophys Res Commun 2019; 509:680-686. [PMID: 30616891 DOI: 10.1016/j.bbrc.2018.12.159] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 12/23/2018] [Indexed: 12/19/2022]
Abstract
Cisplatin causes acute kidney injury (AKI) through proximal tubular injury. We investigated the protective effect of the adenosine monophosphate protein kinase (AMPK) activator 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) against cisplatin-induced AKI. We investigated whether the AMP-kinase activator AICAR ameliorates cisplatin-induced AKI through the JAK/STAT/SOCS pathway. Male Sprague-Dawley (SD) rats were randomly divided into four groups: control, AICAR, cisplatin, and cisplatin + AICAR. As appropriate to their treatment group, the rats were injected with a single dose of cisplatin (7 mg/kg, i.p.). AICAR was administered to the rats at 100 mg/kg i.p. daily. Blood urea nitrogen (BUN) and serum creatinine were measured. Renal damage was analyzed in sections stained with hematoxylin and eosin (H&E). Renal tissues were also examined by immunohistochemistry and western blot for p-AMPK, Kim-1, cleaved caspase 3, and JAK/STAT/SOCS. For in vitro studies, NRK-52E normal rat kidney cells were treated with cisplatin and/or AICAR. By western blot, we confirmed the expression of p-AMPK and the JAK/STAT/SOCS pathway in NRK-52E cells. AICAR was protective against cisplatin-induced acute tubular injury by up-regulating p-AMPK expression in NRK-52E cells. Protein expression levels of JAK2/STAT1 were markedly ameliorated in NRK-52E cells by AICAR. The protective mechanism of AICAR may be associated with suppression of the JAK2/STAT1 pathway and up-regulation of SOCS1, an inhibitor of the JAK2/STAT1 pathway. The present study demonstrates the protective effects of AICAR against cisplatin-induced AKI and shows a new renoprotective mechanism through the JAK2/STAT1/SOCS1 pathway and apoptosis inhibition. This study suggests that activation of the AMPK activator AICAR might ameliorate cisplatin-induced AKI.
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Affiliation(s)
- Bodokhsuren Tsogbadrakh
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul, Republic of Korea
| | - Hyunjin Ryu
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyung Don Ju
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Jinho Lee
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Sohyun Yun
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Kyung-Sang Yu
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul, Republic of Korea
| | - Hyo Jin Kim
- Department of Internal Medicine, Dongkuk University, Kyungju, Republic of Korea
| | - Curie Ahn
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Transplantation Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Kook-Hwan Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
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11
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Involvement of AMP-activated Protein Kinase (AMPK) in Regulation of Cell Membrane Potential in a Gastric Cancer Cell Line. Sci Rep 2018; 8:6028. [PMID: 29662080 PMCID: PMC5902619 DOI: 10.1038/s41598-018-24460-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/12/2018] [Indexed: 12/26/2022] Open
Abstract
Membrane potential (Vmem) is a key bioelectric property of non-excitable cells that plays important roles in regulating cell proliferation. However, the regulation of Vmem itself remains largely unexplored. We found that, under nutrient starvation, during which cell division is inhibited, MKN45 gastric cancer cells were in a hyperpolarized state associated with a high intracellular chloride concentration. AMP-activated protein kinase (AMPK) activity increased, and expression of cystic fibrosis transmembrane conductance regulator (CFTR) decreased, in nutrient-starved cells. Furthermore, the increase in intracellular chloride concentration level and Vmem hyperpolarization in nutrient-starved cells was suppressed by inhibition of AMPK activity. Intracellular chloride concentrations and hyperpolarization increased after over-activation of AMPK using the specific activator AICAR or suppression of CFTR activity using specific inhibitor GlyH-101. Under these conditions, proliferation of MKN45 cells was inhibited. These results reveal that AMPK controls the dynamic change in Vmem by regulating CFTR and influencing the intracellular chloride concentration, which in turn influences cell-cycle progression. These findings offer new insights into the mechanisms underlying cell-cycle arrest regulated by AMPK and CFTR.
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12
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Abstract
Nucleoside diphosphate kinases (NDPKs) are multifunctional proteins encoded by the nme (non-metastatic cells) genes, also called NM23. NDPKs catalyze the transfer of γ-phosphate from nucleoside triphosphates to nucleoside diphosphates by a ping-pong mechanism involving the formation of a high-energy phosphohistidine intermediate. Growing evidence shows that NDPKs, particularly NDPK-B, can additionally act as a protein histidine kinase. Protein kinases and phosphatases that regulate reversible O-phosphorylation of serine, threonine, and tyrosine residues have been studied extensively in many organisms. Interestingly, other phosphoamino acids histidine, lysine, arginine, aspartate, glutamate, and cysteine exist in abundance but remain understudied due to the paucity of suitable methods and antibodies. The N-phosphorylation of histidine by histidine kinases via the two- or multi-component signaling systems is an important mediator in cellular responses in prokaryotes and lower eukaryotes, like yeast, fungi, and plants. However, in vertebrates knowledge of phosphohistidine signaling has lagged far behind and the identity of the protein kinases and protein phosphatases involved is not well established. This article will therefore provide an overview of our current knowledge on protein histidine phosphorylation particularly the role of nm 23 gene products as protein histidine kinases.
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Affiliation(s)
- Paul V Attwood
- School of Molecular Sciences, The University of Western Australia (M310), Crawley, WA, Australia
| | - Richmond Muimo
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, University of Sheffield, Sheffield, UK
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13
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Makwana MV, Muimo R, Jackson RF. Advances in development of new tools for the study of phosphohistidine. J Transl Med 2018; 98:291-303. [PMID: 29200202 DOI: 10.1038/labinvest.2017.126] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 08/27/2017] [Accepted: 09/03/2017] [Indexed: 01/04/2023] Open
Abstract
Protein phosphorylation is an important post-translational modification that is an integral part of cellular function. The O-phosphorylated amino-acid residues, such as phosphoserine (pSer), phosphothreonine (pThr) and phosphotyrosine (pTyr), have dominated the literature while the acid labile N-linked phosphorylated amino acids, such as phosphohistidine (pHis), have largely been historically overlooked because of the acidic conditions routinely used in amino-acid detection and analysis. This review highlights some misinterpretations that have arisen in the existing literature, pinpoints outstanding questions and potential future directions to clarify the role of pHis in mammalian signalling systems. Particular emphasis is placed on pHis isomerization and the hybrid functionality for both pHis and pTyr of the proposed τ-pHis analogue bearing the triazole residue.
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Affiliation(s)
- Mehul V Makwana
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK.,Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield S10 2RX, UK
| | - Richmond Muimo
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield S10 2RX, UK
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14
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The actions of NME1/NDPK-A and NME2/NDPK-B as protein kinases. J Transl Med 2018; 98:283-290. [PMID: 29200201 DOI: 10.1038/labinvest.2017.125] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Revised: 09/28/2017] [Accepted: 10/01/2017] [Indexed: 12/26/2022] Open
Abstract
Nucleoside diphosphate kinases (NDPKs) are multifunctional proteins encoded by the nme (non-metastatic cells) genes, also called NM23. NDPKs catalyze the transfer of γ-phosphate from nucleoside triphosphates to nucleoside diphosphates by a ping-pong mechanism involving the formation of a high-energy phosphohistidine intermediate. Growing evidence shows that NDPKs, particularly NDPK-B, can additionally act as a protein histidine kinase. Protein kinases and phosphatases that regulate reversible O-phosphorylation of serine, threonine, and tyrosine residues have been studied extensively in many organisms. Interestingly, other phosphoamino acids histidine, lysine, arginine, aspartate, glutamate, and cysteine exist in abundance but remain understudied due to the paucity of suitable methods and antibodies. The N-phosphorylation of histidine by histidine kinases via the two- or multi-component signaling systems is an important mediator in cellular responses in prokaryotes and lower eukaryotes, like yeast, fungi, and plants. However, in vertebrates knowledge of phosphohistidine signaling has lagged far behind and the identity of the protein kinases and protein phosphatases involved is not well established. This article will therefore provide an overview of our current knowledge on protein histidine phosphorylation particularly the role of nm 23 gene products as protein histidine kinases.
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15
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Muimo R, Alothaid HM, Mehta A. NM23 proteins: innocent bystanders or local energy boosters for CFTR? J Transl Med 2018; 98:272-282. [PMID: 29251738 DOI: 10.1038/labinvest.2017.121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Revised: 08/25/2017] [Accepted: 09/12/2017] [Indexed: 12/17/2022] Open
Abstract
NM23 proteins NDPK-A and -B bind to the cystic fibrosis (CF) protein CFTR in different ways from kinases such as PKA, CK2 and AMPK or linkers to cell calcium such as calmodulin and annexins. NDPK-A (not -B) interacts with CFTR through reciprocal AMPK binding/control, whereas NDPK-B (not -A) binds directly to CFTR. NDPK-B can activate G proteins without ligand-receptor coupling, so perhaps NDPK-B's binding influences energy supply local to a nucleotide-binding site (NBD1) needed for CFTR to function. Curiously, CFTR (ABC-C7) is a member of the ATP-binding cassette (ABC) protein family that does not obey 'clan rules'; CFTR channels anions and is not a pump, regulates disparate processes, is itself regulated by multiple means and is so pleiotropic that it acts as a hub that orchestrates calcium signaling through its consorts such as calmodulin/annexins. Furthermore, its multiple partners make CFTR dance to different tunes in different cellular and subcellular locations as it recycles from the plasma membrane to endosomes. CFTR function in airway apical membranes is inhibited by smoking which has been dubbed 'acquired CF'. CFTR alone among family members possesses a trap for other proteins that it unfurls as a 'fish-net' and which bears consensus phosphorylation sites for many protein kinases, with PKA being the most canonical. Recently, the site of CFTR's commonest mutation has been proposed as a knock-in mutant that alters allosteric control of kinase CK2 by log orders of activity towards calmodulin and other substrates after CFTR fragmentation. This link from CK2 to calmodulin that binds the R region invokes molecular paths that control lumen formation, which is incomplete in the tracheas of some CF-affected babies. Thus, we are poised to understand the many roles of NDPK-A and -B in CFTR function and, especially lumen formation, which is defective in the gut and lungs of many CF babies.
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Affiliation(s)
- Richmond Muimo
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, University of Sheffield, Sheffield, UK
| | - Hani Mm Alothaid
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, University of Sheffield, Sheffield, UK
| | - Anil Mehta
- Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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16
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Jiang S, Li T, Yang Z, Yi W, Di S, Sun Y, Wang D, Yang Y. AMPK orchestrates an elaborate cascade protecting tissue from fibrosis and aging. Ageing Res Rev 2017; 38:18-27. [PMID: 28709692 DOI: 10.1016/j.arr.2017.07.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 07/07/2017] [Accepted: 07/10/2017] [Indexed: 01/10/2023]
Abstract
Fibrosis is a common process characterized by excessive extracellular matrix (ECM) accumulation after inflammatory injury, which is also a crucial cause of aging. The process of fibrosis is involved in the pathogenesis of most diseases of the heart, liver, kidney, lung, and other organs/tissues. However, there are no effective therapies for this pathological alteration. Annually, fibrosis represents a huge financial burden for the USA and the world. 5'-AMP-activated protein kinase (AMPK) is a pivotal energy sensor that alleviates or delays the process of fibrogenesis. In this review, we first present basic background information on AMPK and fibrogenesis and describe the protective roles of AMPK in three fibrogenic phases. Second, we analyze the protective action of AMPK during fibrosis in myocardial, hepatic, renal, pulmonary, and other organs/tissues. Third, we present a comprehensive discussion of AMPK during fibrosis and draw a conclusion. This review highlights recent advances, vital for basic research and clinical drug design, in the regulation of AMPK during fibrosis.
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Affiliation(s)
- Shuai Jiang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education. Faculty of Life Sciences, Northwest University, 229 Taibai North Road, Xi'an 710069, China; Department of Aerospace Medicine, The Fourth Military Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Tian Li
- Department of Biomedical Engineering, The Fourth Military Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Zhi Yang
- Department of Biomedical Engineering, The Fourth Military Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Wei Yi
- Department of Cardiovascular Surgery, Xijing Hospital, The Fourth Military Medical University, 127 Changle West Road, Xi'an 710032, China
| | - Shouyin Di
- Department of Thoracic Surgery, Tangdu Hospital, The Fourth Military Medical University, 1 Xinsi Road, Xi'an 710038, China
| | - Yang Sun
- Department of Geriatrics, Xijing Hospital, The Fourth Military Medical University, 127 Changle West Road, Xi'an 710032, China
| | - Dongjin Wang
- Department of Thoracic and Cardiovascular Surgery, Affiliated Drum Tower Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing 210008, Jiangsu, China
| | - Yang Yang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education. Faculty of Life Sciences, Northwest University, 229 Taibai North Road, Xi'an 710069, China; Department of Biomedical Engineering, The Fourth Military Medical University, 169 Changle West Road, Xi'an 710032, China.
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17
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Liang Z, Li T, Jiang S, Xu J, Di W, Yang Z, Hu W, Yang Y. AMPK: a novel target for treating hepatic fibrosis. Oncotarget 2017; 8:62780-62792. [PMID: 28977988 PMCID: PMC5617548 DOI: 10.18632/oncotarget.19376] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 07/08/2017] [Indexed: 12/19/2022] Open
Abstract
Fibrosis is a common process of excessive extracellular matrix (ECM) accumulation following inflammatory injury. Fibrosis is involved in the pathogenesis of almost all liver diseases for which there is no effective treatment. 5'-AMP-activated protein kinase (AMPK) is a cellular energy sensor that can ameliorate the process of hepatic fibrogenesis. Given the existing evidence, we first introduce the basic background of AMPK and hepatic fibrosis and the actions of AMPK in hepatic fibrosis. Second, we discuss the three phases of hepatic fibrosis and potential drugs that target AMPK. Third, we analyze possible anti-fibrosis mechanisms and other benefits of AMPK on the liver. Finally, we summarize and briefly explain the current objections to targeting AMPK. This review may aid clinical and basic research on AMPK, which may be a novel drug candidate for hepatic fibrosis.
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Affiliation(s)
- Zhenxing Liang
- Department of Cardiothoracic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Tian Li
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Xi'an 710069, China.,Department of Biomedical Engineering, The Fourth Military Medical University, Xi'an 710032, China
| | - Shuai Jiang
- Department of Aerospace Medicine, The Fourth Military Medical University, Xi'an 710032, China
| | - Jing Xu
- Department of Cardiothoracic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Wencheng Di
- Department of Cardiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Zhi Yang
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi'an 710032, China
| | - Wei Hu
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi'an 710032, China
| | - Yang Yang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Xi'an 710069, China.,Department of Biomedical Engineering, The Fourth Military Medical University, Xi'an 710032, China
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18
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Wujak M, Hetmann A, Porowińska D, Roszek K. Gene Expression and Activity Profiling Reveal a Significant Contribution of Exo-Phosphotransferases to the Extracellular Nucleotides Metabolism in HUVEC Endothelial Cells. J Cell Biochem 2017; 118:1341-1348. [PMID: 27859553 DOI: 10.1002/jcb.25791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/10/2016] [Indexed: 01/22/2023]
Abstract
Purinergic signaling maintains local tissue homeostasis in blood vessels via the regulation of vascular tone, blood platelet aggregation, cell proliferation, and differentiation as well as inflammatory responses. Extracellular purines are important signaling molecules in the vasculature, and both purine-hydrolysing as well as -phosphorylating enzymes are considered to selectively govern extracellular nucleotide/nucleoside metabolism. Recent studies have provided some evidence for the existence of these enzymes in a soluble form in human blood and their secretion into the extracellular space under physiological and pathological conditions. However, the comprehensive analysis of endothelium-derived enzymes involved in purine metabolic pathways has received no attention so far. In the presented study, in vitro cultured human umbilical vein endothelial cells (HUVEC) are shown to be an abundant source of exo-nucleotidases comprising 5'-nucleotidase (exo-5'-NT), and nucleoside triphosphate diphosphohydrolases (exo-NTPDase) as well as phosphotransferases, represented by nucleoside diphosphate kinase (exo-NDPK) and adenylate kinase (exo-AK). An attempt is also made to demonstrate that, in contrast to the metabolic pattern determined on the endothelial cell surface, exo-phosphorylating activities markedly predominate over exo-hydrolytic ones. We present for the first time the expression profiles of genes encoding isoenzymes belonging to distinct nucleotide kinase and nucleotidase families. The genes encoding NDPK1, NDPK2, AK1, and AK2 phosphotransferases have been shown to be expressed at the highest level in HUVEC cells. The data indicate the coexistence of secreted and cell-associated factors of endothelial origin mediating ATP-consuming and ATP-generating pathways with the predominance of exo-phosphotransferases activity. The described enzymes contribute to the regulation of purinergic signal duration and extent in the venous vasculature. J. Cell. Biochem. 118: 1341-1348, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Magdalena Wujak
- Department of Biochemistry, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, 1 Lwowska St, 87-100, Toruń, Poland
| | - Anna Hetmann
- Department of Biochemistry, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, 1 Lwowska St, 87-100, Toruń, Poland
| | - Dorota Porowińska
- Department of Biochemistry, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, 1 Lwowska St, 87-100, Toruń, Poland
| | - Katarzyna Roszek
- Department of Biochemistry, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, 1 Lwowska St, 87-100, Toruń, Poland
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19
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Role of Interaction and Nucleoside Diphosphate Kinase B in Regulation of the Cystic Fibrosis Transmembrane Conductance Regulator Function by cAMP-Dependent Protein Kinase A. PLoS One 2016; 11:e0149097. [PMID: 26950439 PMCID: PMC4780765 DOI: 10.1371/journal.pone.0149097] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 01/27/2016] [Indexed: 02/05/2023] Open
Abstract
Cystic fibrosis results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-dependent protein kinase A (PKA) and ATP-regulated chloride channel. Here, we demonstrate that nucleoside diphosphate kinase B (NDPK-B, NM23-H2) forms a functional complex with CFTR. In airway epithelia forskolin/IBMX significantly increases NDPK-B co-localisation with CFTR whereas PKA inhibitors attenuate complex formation. Furthermore, an NDPK-B derived peptide (but not its NDPK-A equivalent) disrupts the NDPK-B/CFTR complex in vitro (19-mers comprising amino acids 36–54 from NDPK-B or NDPK-A). Overlay (Far-Western) and Surface Plasmon Resonance (SPR) analysis both demonstrate that NDPK-B binds CFTR within its first nucleotide binding domain (NBD1, CFTR amino acids 351–727). Analysis of chloride currents reflective of CFTR or outwardly rectifying chloride channels (ORCC, DIDS-sensitive) showed that the 19-mer NDPK-B peptide (but not its NDPK-A equivalent) reduced both chloride conductances. Additionally, the NDPK-B (but not NDPK-A) peptide also attenuated acetylcholine-induced intestinal short circuit currents. In silico analysis of the NBD1/NDPK-B complex reveals an extended interaction surface between the two proteins. This binding zone is also target of the 19-mer NDPK-B peptide, thus confirming its capability to disrupt NDPK-B/CFTR complex. We propose that NDPK-B forms part of the complex that controls chloride currents in epithelia.
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20
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Takács-Vellai K, Vellai T, Farkas Z, Mehta A. Nucleoside diphosphate kinases (NDPKs) in animal development. Cell Mol Life Sci 2015. [PMID: 25537302 DOI: 10.07/s00018-014-1803-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In textbooks of biochemistry, nucleoside diphosphate conversion to a triphosphate by nucleoside diphosphate 'kinases' (NDPKs, also named NME or NM23 proteins) merits a few lines of text. Yet this essential metabolic function, mediated by a multimeric phosphotransferase protein, has effects that lie beyond a simple housekeeping role. NDPKs attracted more attention when NM23-H1 was identified as the first metastasis suppressor gene. In this review, we examine these NDPK enzymes from a developmental perspective because of the tractable phenotypes found in simple animal models that point to common themes. The data suggest that NDPK enzymes control the availability of surface receptors to regulate cell-sensing cues during cell migration. NDPKs regulate different forms of membrane enclosure that engulf dying cells during development. We suggest that NDPK enzymes have been essential for the regulated uptake of objects such as bacteria or micronutrients, and this evolutionarily conserved endocytic function contributes to their activity towards the regulation of metastasis.
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Affiliation(s)
- Krisztina Takács-Vellai
- Department of Biological Anthropology, Eötvös Loránd University, Pázmány Péter stny. 1/C, 1117, Budapest, Hungary,
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21
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Takács-Vellai K, Vellai T, Farkas Z, Mehta A. Nucleoside diphosphate kinases (NDPKs) in animal development. Cell Mol Life Sci 2015; 72:1447-62. [PMID: 25537302 PMCID: PMC11113130 DOI: 10.1007/s00018-014-1803-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 12/04/2014] [Accepted: 12/08/2014] [Indexed: 12/25/2022]
Abstract
In textbooks of biochemistry, nucleoside diphosphate conversion to a triphosphate by nucleoside diphosphate 'kinases' (NDPKs, also named NME or NM23 proteins) merits a few lines of text. Yet this essential metabolic function, mediated by a multimeric phosphotransferase protein, has effects that lie beyond a simple housekeeping role. NDPKs attracted more attention when NM23-H1 was identified as the first metastasis suppressor gene. In this review, we examine these NDPK enzymes from a developmental perspective because of the tractable phenotypes found in simple animal models that point to common themes. The data suggest that NDPK enzymes control the availability of surface receptors to regulate cell-sensing cues during cell migration. NDPKs regulate different forms of membrane enclosure that engulf dying cells during development. We suggest that NDPK enzymes have been essential for the regulated uptake of objects such as bacteria or micronutrients, and this evolutionarily conserved endocytic function contributes to their activity towards the regulation of metastasis.
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Affiliation(s)
- Krisztina Takács-Vellai
- Department of Biological Anthropology, Eötvös Loránd University, Pázmány Péter stny. 1/C, 1117, Budapest, Hungary,
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22
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The ubiquitin E3 ligase SCF-FBXO24 recognizes deacetylated nucleoside diphosphate kinase A to enhance its degradation. Mol Cell Biol 2015; 35:1001-13. [PMID: 25582197 DOI: 10.1128/mcb.01185-14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Skp-Cul-F box (SCF) ubiquitin E3 ligase machinery recognizes predominantly phosphodegrons or, less commonly, an (I/L)Q molecular signature within substrates to facilitate their recruitment in mediating protein ubiquitination and degradation. Here, we examined the molecular signals that determine the turnover of the multifunctional enzyme nucleoside diphosphate kinase A (NDPK-A) that controls cell proliferation. NDPK-A protein exhibits a half-life of ∼6 h in HeLa cells and is targeted for ubiquitylation through actions of the F-box protein FBXO24. SCF-FBXO24 polyubiquitinates NDPK-A at K85, and two NH(2)-terminal residues, L55 and K56, were identified as important molecular sites for FBXO24 interaction. Importantly, K56 acetylation impairs its interaction with FBXO24, and replacing K56 with Q56, an acetylation mimic, reduces NDPK-A FBXO24 binding capacity. The acetyltransferase GCN5 catalyzes K56 acetylation within NDPK-A, thereby stabilizing NDPK-A, whereas GCN5 depletion in cells accelerates NDPK-A degradation. Cellular expression of an NDPK-A acetylation mimic or FBXO24 silencing increases NDPK-A life span which, in turn, impairs cell migration and wound healing. We propose that lysine acetylation when presented in the appropriate context may be recognized by some F-box proteins as a unique inhibitory molecular signal for their recruitment to restrict substrate degradation.
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Francois-Moutal L, Marcillat O, Granjon T. Structural comparison of highly similar nucleoside-diphosphate kinases: Molecular explanation of distinct membrane-binding behavior. Biochimie 2014; 105:110-8. [DOI: 10.1016/j.biochi.2014.06.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 06/30/2014] [Indexed: 02/06/2023]
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24
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Mohd Mokhtar H, Giribabu N, Kassim N, Muniandy S, Salleh N. Testosterone decreases fluid and chloride secretions in the uterus of adult female rats via down-regulating cystic fibrosis transmembrane regulator (CFTR) expression and functional activity. J Steroid Biochem Mol Biol 2014; 144 Pt B:361-72. [PMID: 25125390 DOI: 10.1016/j.jsbmb.2014.08.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 07/14/2014] [Accepted: 08/07/2014] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Estrogen is known to stimulate uterine fluid and Cl(-) secretion via CFTR. This study investigated testosterone effect on these changes in a rat model. METHODS Ovariectomized adult female rats received estrogen for five days or estrogen for three days followed by two days peanut oil or testosterone either alone or in the presence of flutamide or finasteride. At the end of treatment, uteri were perfused with perfusate containing CFTRinh-172. The rate of fluid and Cl(-) secretion were determined. Dose-dependent effect of testosterone and effect of forskolin on fluid secretion rate were measured. Animals were sacrificed and uteri were removed for CFTR protein and mRNA expression analyses, histology and cAMP measurement. Morphology of uterus, levels of expression of CFTR protein and mRNA and distribution of CFTR protein were observed. RESULTS Estrogen causes increase while testosterone causes decrease in uterine fluid and Cl(-) secretions. The effects of estrogen but not testosterone were antagonized by CFTRinh-172. Luminal fluid volume and apical expression of CFTR in the luminal epithelia were highest under estrogen and lowest under testosterone influences. Similar changes were observed in CFTR protein and mRNA expressions. Uterine cAMP level was highest under estrogen and lowest under testosterone influence. Forskolin increases fluid secretion rate in estrogen but not in testosterone-treated animals. Testosterone effects were dose-dependent and were antagonized by flutamide however, not finasteride. CONCLUSIONS Testosterone inhibition of estrogen-induced uterine fluid and Cl(-) secretion occurs via inhibition of CFTR expression and functional activities. These changes could explain the adverse effects of testosterone on fertility.
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Affiliation(s)
- Helmy Mohd Mokhtar
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Nelli Giribabu
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Normadiah Kassim
- Department of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Sekaran Muniandy
- Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Naguib Salleh
- Department of Physiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
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25
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Ward JBJ, Keely SJ, Keely SJ. Oxygen in the regulation of intestinal epithelial transport. J Physiol 2014; 592:2473-89. [PMID: 24710059 DOI: 10.1113/jphysiol.2013.270249] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The transport of fluid, nutrients and electrolytes to and from the intestinal lumen is a primary function of epithelial cells. Normally, the intestine absorbs approximately 9 l of fluid and 1 kg of nutrients daily, driven by epithelial transport processes that consume large amounts of cellular energy and O2. The epithelium exists at the interface of the richly vascularised mucosa, and the anoxic luminal environment and this steep O2 gradient play a key role in determining the expression pattern of proteins involved in fluid, nutrient and electrolyte transport. However, the dynamic nature of the splanchnic circulation necessitates that the epithelium can evoke co-ordinated responses to fluctuations in O2 availability, which occur either as a part of the normal digestive process or as a consequence of several pathophysiological conditions. While it is known that hypoxia-responsive signals, such as reactive oxygen species, AMP-activated kinase, hypoxia-inducible factors, and prolyl hydroxylases are all important in regulating epithelial responses to altered O2 supply, our understanding of the molecular mechanisms involved is still limited. Here, we aim to review the current literature regarding the role that O2 plays in regulating intestinal transport processes and to highlight areas of research that still need to be addressed.
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Affiliation(s)
- Joseph B J Ward
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Simon J Keely
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle NSW, Australia
| | - Stephen J Keely
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
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Kunzelmann K, Mehta A. CFTR: a hub for kinases and crosstalk of cAMP and Ca2+. FEBS J 2013; 280:4417-29. [PMID: 23895508 DOI: 10.1111/febs.12457] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/29/2013] [Accepted: 07/02/2013] [Indexed: 12/17/2022]
Abstract
Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR). The resulting disease is pleiotropic consistent with the idea that CFTR acts as a node within a network of signalling proteins. CFTR is not only a regulator of multiple transport proteins and controlled by numerous kinases but also participates in many signalling pathways that are disrupted after expression of its commonest mutant (F508del-CFTR). It operates in membrane compartments creating a scaffold for cytoskeletal elements, surface receptors, kinases and phosphodiesterases. CFTR is exposed to membrane-local second messengers such that a CFTR-interacting, low cellular energy sensor kinase (AMP- and ADP-activated kinase, AMPK) signals through a high energy phosphohistidine protein kinase (nucleoside diphosphate kinase, NDPK). CFTR also translocates a Ca(2+)-dependent adenylate cyclase to its proximity so that a rigid separation between cAMP-dependent and Ca(2+)-dependent regulation of Cl(-) transport becomes obsolete. In the presence of wild-type CFTR, parallel activation of CFTR and outwardly rectifying anoctamin 6 Cl(-) channels is observed, while the Ca(2+)-activated anoctamin 1 Cl(-) channel is inhibited. In contrast, in CF cells, CFTR is missing/mislocalized and the outwardly rectifying chloride channel is attenuated while Ca(2+)-dependent Cl(-) secretion (anoctamin 1) appears upregulated. Additionally, we consider the idea that F508del-CFTR when trapped in the endoplasmic reticulum augments IP3-mediated Ca(2+) release by providing a shunt pathway for Cl(-). CFTR and the IP3 receptor share the characteristic that they both assemble their partner proteins to increase the plasticity of their hub responses. In CF, the CFTR hub fails to form at the plasma membrane, with widespread detrimental consequences for cell signalling.
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Zhang JT, Jiang XH, Xie C, Cheng H, Da Dong J, Wang Y, Fok KL, Zhang XH, Sun TT, Tsang LL, Chen H, Sun XJ, Chung YW, Cai ZM, Jiang WG, Chan HC. Downregulation of CFTR promotes epithelial-to-mesenchymal transition and is associated with poor prognosis of breast cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2961-2969. [PMID: 23916755 DOI: 10.1016/j.bbamcr.2013.07.021] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 07/22/2013] [Accepted: 07/24/2013] [Indexed: 01/12/2023]
Abstract
The epithelial-to-mesenchymal transition (EMT), a process involving the breakdown of cell-cell junctions and loss of epithelial polarity, is closely related to cancer development and metastatic progression. While the cystic fibrosis transmembrane conductance regulator (CFTR), a Cl(-) and HCO3(-) conducting anion channel expressed in a wide variety of epithelial cells, has been implicated in the regulation of epithelial polarity, the exact role of CFTR in the pathogenesis of cancer and its possible involvement in EMT process have not been elucidated. Here we report that interfering with CFTR function either by its specific inhibitor or lentiviral miRNA-mediated knockdown mimics TGF-β1-induced EMT and enhances cell migration and invasion in MCF-7. Ectopic overexpression of CFTR in a highly metastatic MDA-231 breast cancer cell line downregulates EMT markers and suppresses cell invasion and migration in vitro, as well as metastasis in vivo. The EMT-suppressing effect of CFTR is found to be associated with its ability to inhibit NFκB targeting urokinase-type plasminogen activator (uPA), known to be involved in the regulation of EMT. More importantly, CFTR expression is found significantly downregulated in primary human breast cancer samples, and is closely associated with poor prognosis in different cohorts of breast cancer patients. Taken together, the present study has demonstrated a previously undefined role of CFTR as an EMT suppressor and its potential as a prognostic indicator in breast cancer.
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Affiliation(s)
- Jie Ting Zhang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Xiao Hua Jiang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong; Key Laboratory for Regenerative Medicine, Ji Nan University-The Chinese University of Hong Kong, Ministry of Education of The People's Republic of China, China
| | - Chen Xie
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Hong Cheng
- Department of Pathology, State Key Laboratory of Cancer Biology, Xijing Hospital and School of Basic Medicine, Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Jian Da Dong
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Yan Wang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Kin Lam Fok
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Xiao Hu Zhang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Ting Ting Sun
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Lai Ling Tsang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Hao Chen
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong; Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Xiao Juan Sun
- Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Yiu Wa Chung
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Zhi Ming Cai
- Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Wen Guo Jiang
- Metastasis and Angiogenesis Research Group, Department of Surgery, Cardiff University School of Medicine, Cardiff, UK.
| | - Hsiao Chang Chan
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong; Key Laboratory for Regenerative Medicine, Ji Nan University-The Chinese University of Hong Kong, Ministry of Education of The People's Republic of China, China; Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Chengdu, China.
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Rogers AC, Huetter L, Hoekstra N, Collins D, Collaco A, Baird AW, Winter DC, Ameen N, Geibel JP, Kopic S. Activation of AMPK inhibits cholera toxin stimulated chloride secretion in human and murine intestine. PLoS One 2013; 8:e69050. [PMID: 23935921 PMCID: PMC3728293 DOI: 10.1371/journal.pone.0069050] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 06/03/2013] [Indexed: 02/07/2023] Open
Abstract
Increased intestinal chloride secretion through chloride channels, such as the cystic fibrosis transmembrane conductance regulator (CFTR), is one of the major molecular mechanisms underlying enterotoxigenic diarrhea. It has been demonstrated in the past that the intracellular energy sensing kinase, the AMP-activated protein kinase (AMPK), can inhibit CFTR opening. We hypothesized that pharmacological activation of AMPK can abrogate the increased chloride flux through CFTR occurring during cholera toxin (CTX) mediated diarrhea. Chloride efflux was measured in isolated rat colonic crypts using real-time fluorescence imaging. AICAR and metformin were used to activate AMPK in the presence of the secretagogues CTX or forskolin (FSK). In order to substantiate our findings on the whole tissue level, short-circuit current (SCC) was monitored in human and murine colonic mucosa using Ussing chambers. Furthermore, fluid accumulation was measured in excised intestinal loops. CTX and forskolin (FSK) significantly increased chloride efflux in isolated colonic crypts. The increase in chloride efflux could be offset by using the AMPK activators AICAR and metformin. In human and mouse mucosal sheets, CTX and FSK increased SCC. AICAR and metformin inhibited the secretagogue induced rise in SCC, thereby confirming the findings made in isolated crypts. Moreover, AICAR decreased CTX stimulated fluid accumulation in excised intestinal segments. The present study suggests that pharmacological activation of AMPK effectively reduces CTX mediated increases in intestinal chloride secretion, which is a key factor for intestinal water accumulation. AMPK activators may therefore represent a supplemental treatment strategy for acute diarrheal illness.
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Affiliation(s)
- Ailín C. Rogers
- University College Dublin and St. Vincent's University Hospital, Dublin, Ireland
| | - Lisa Huetter
- Institute of Physiology and Pathophysiology, Paracelsus Medical University, Salzburg, Austria
- Department of Surgery, Yale University, School of Medicine, New Haven, Connecticut, United States of America
| | - Nadia Hoekstra
- Department of Pediatrics, Yale University, School of Medicine, New Haven, Connecticut, United States of America
| | - Danielle Collins
- University College Dublin and St. Vincent's University Hospital, Dublin, Ireland
| | - Anne Collaco
- Department of Pediatrics, Yale University, School of Medicine, New Haven, Connecticut, United States of America
| | - Alan W. Baird
- University College Dublin and St. Vincent's University Hospital, Dublin, Ireland
| | - Desmond C. Winter
- University College Dublin and St. Vincent's University Hospital, Dublin, Ireland
| | - Nadia Ameen
- Department of Pediatrics, Yale University, School of Medicine, New Haven, Connecticut, United States of America
- Department of Cellular and Molecular Physiology, Yale University, School of Medicine, New Haven, Connecticut, United States of America
| | - John P. Geibel
- Department of Surgery, Yale University, School of Medicine, New Haven, Connecticut, United States of America
- Department of Cellular and Molecular Physiology, Yale University, School of Medicine, New Haven, Connecticut, United States of America
| | - Sascha Kopic
- Department of Surgery, Yale University, School of Medicine, New Haven, Connecticut, United States of America
- Department of Cellular and Molecular Physiology, Yale University, School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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29
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Bozoky Z, Krzeminski M, Chong PA, Forman-Kay JD. Structural changes of CFTR R region upon phosphorylation: a plastic platform for intramolecular and intermolecular interactions. FEBS J 2013; 280:4407-16. [PMID: 23826884 PMCID: PMC4160016 DOI: 10.1111/febs.12422] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 06/24/2013] [Accepted: 07/02/2013] [Indexed: 11/29/2022]
Abstract
Chloride channel gating and trafficking of the cystic fibrosis transmembrane conductance regulator (CFTR) are regulated by phosphorylation. Intrinsically disordered segments of the protein are responsible for phospho‐regulation, particularly the regulatory (R) region that is a target for several kinases and phosphatases. The R region remains disordered following phosphorylation, with different phosphorylation states sampling various conformations. Recent studies have demonstrated the crucial role that intramolecular and intermolecular interactions of the R region play in CFTR regulation. Different partners compete for the same binding segment, with the R region containing multiple overlapping binding elements. The non‐phosphorylated R region interacts with the nucleotide binding domains and inhibits channel activity by blocking heterodimerization. Phosphorylation shifts the equilibrium such that the R region is excluded from the dimer interface, facilitating gating and processing by stimulating R region interactions with other domains and proteins. The dynamic conformational sampling and transient binding of the R region to multiple partners enables complex control of CFTR channel activity and trafficking.
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Affiliation(s)
- Zoltan Bozoky
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario, Canada
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