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Rawat SS, Keshri AK, Arora N, Kaur R, Mishra A, Kumar R, Prasad A. Taenia solium cysticerci's extracellular vesicles Attenuate the AKT/mTORC1 pathway for Alleviating DSS-induced colitis in a murine model. J Extracell Vesicles 2024; 13:e12448. [PMID: 38779712 PMCID: PMC11112404 DOI: 10.1002/jev2.12448] [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: 08/21/2023] [Revised: 03/24/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
The excretory-secretory proteome plays a pivotal role in both intercellular communication during disease progression and immune escape mechanisms of various pathogens including cestode parasites like Taenia solium. The cysticerci of T. solium causes infection in the central nervous system known as neurocysticercosis (NCC), which affects a significant population in developing countries. Extracellular vesicles (EVs) are 30-150-nm-sized particles and constitute a significant part of the secretome. However, the role of EV in NCC pathogenesis remains undetermined. Here, for the first time, we report that EV from T. solium larvae is abundant in metabolites that can negatively regulate PI3K/AKT pathway, efficiently internalized by macrophages to induce AKT and mTOR degradation through auto-lysosomal route with a prominent increase in the ubiquitination of both proteins. This results in less ROS production and diminished bacterial killing capability among EV-treated macrophages. Due to this, both macro-autophagy and caspase-linked apoptosis are upregulated, with a reduction of the autophagy substrate sequestome 1. In summary, we report that T. solium EV from viable cysts attenuates the AKT-mTOR pathway thereby promoting apoptosis in macrophages, and this may exert immunosuppression during an early viable stage of the parasite in NCC, which is primarily asymptomatic. Further investigation on EV-mediated immune suppression revealed that the EV can protect the mice from DSS-induced colitis and improve colon architecture. These findings shed light on the previously unknown role of T. solium EV and the therapeutic role of their immune suppression potential.
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Affiliation(s)
- Suraj Singh Rawat
- School of Biosciences and BioengineeringIndian Institute of Technology MandiMandiHimachal PradeshIndia
| | - Anand Kumar Keshri
- School of Biosciences and BioengineeringIndian Institute of Technology MandiMandiHimachal PradeshIndia
| | - Naina Arora
- School of Biosciences and BioengineeringIndian Institute of Technology MandiMandiHimachal PradeshIndia
| | - Rimanpreet Kaur
- School of Biosciences and BioengineeringIndian Institute of Technology MandiMandiHimachal PradeshIndia
| | - Amit Mishra
- Cellular and Molecular Neurobiology UnitIndian Institute of Technology JodhpurJodhpurRajasthanIndia
| | - Rajiv Kumar
- CSIR‐Institute of Himalayan Bioresource TechnologyPalampurHimachal PradeshIndia
| | - Amit Prasad
- School of Biosciences and BioengineeringIndian Institute of Technology MandiMandiHimachal PradeshIndia
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2
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Chakkour M, Greenberg ML. Insights into the roles of inositol hexakisphosphate kinase 1 (IP6K1) in mammalian cellular processes. J Biol Chem 2024; 300:107116. [PMID: 38403246 PMCID: PMC11065760 DOI: 10.1016/j.jbc.2024.107116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/12/2024] [Accepted: 02/14/2024] [Indexed: 02/27/2024] Open
Abstract
Inositol phosphates and their metabolites play a significant role in several biochemical pathways, gene expression regulation, and phosphate homeostasis. Among the different inositol phosphates, inositol hexakisphosphate (IP6) is a substrate of inositol hexakisphosphate kinases (IP6Ks), which phosphorylate one or more of the IP6 phosphate groups. Pyrophosphorylation of IP6 leads to the formation of inositol pyrophosphates, high-energy signaling molecules that mediate physiological processes through their ability to modify target protein activities, either by directly binding to their target protein or by pyrophosphorylating protein serine residues. 5-diphosphoinositol pentakisphosphate, the most abundant inositol pyrophosphate in mammals, has been extensively studied and found to be significantly involved in a wide range of physiological processes. Three IP6K (IP6K1, IP6K2, and IP6K3) isoforms regulate IP7 synthesis in mammals. Here, we summarize our current understanding of IP6K1's roles in cytoskeletal remodeling, trafficking, cellular migration, metabolism, gene expression, DNA repair, and immunity. We also briefly discuss current gaps in knowledge, highlighting the need for further investigation.
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Affiliation(s)
- Mohamed Chakkour
- Department of Biological Sciences, Wayne State University, Detroit, Michigan, USA
| | - Miriam L Greenberg
- Department of Biological Sciences, Wayne State University, Detroit, Michigan, USA.
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3
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Huang Q, Ru Y, Luo Y, Luo X, Liu D, Ma Y, Zhou X, Linghu M, Xu W, Gao F, Huang Y. Identification of a targeted ACSL4 inhibitor to treat ferroptosis-related diseases. SCIENCE ADVANCES 2024; 10:eadk1200. [PMID: 38552012 PMCID: PMC10980261 DOI: 10.1126/sciadv.adk1200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 02/23/2024] [Indexed: 04/01/2024]
Abstract
Ferroptosis is a form of iron-dependent, lipid peroxidation-driven regulatory cell death that has been implicated in the pathogenesis of multiple diseases, including organ injury, ischemia/reperfusion, and neurodegenerative diseases. However, inhibitors that directly and specifically target ferroptosis are not yet available. Here, we identify the compound AS-252424 (AS) as a potent ferroptosis inhibitor through kinase inhibitor library screening. Our results show that AS effectively inhibits lipid peroxidation and ferroptosis in both human and mouse cells. Mechanistically, AS directly binds to the glutamine 464 of ACSL4 to inhibit its enzymatic activity, resulting in the suppression of lipid peroxidation and ferroptosis. By using nanoparticle-based delivery systems, treatment with AS-loaded nanoparticles effectively alleviate ferroptosis-mediated organ injury in mouse models, including kidney ischemia/reperfusion injury and acute liver injury (ALI). Thus, our results identify that AS is a specific and targeted inhibitor of ACSL4 with remarkable antiferroptosis function, providing a potential therapeutic for ferroptosis-related diseases.
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Affiliation(s)
- Qian Huang
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Yi Ru
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Yingli Luo
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Xianyu Luo
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Didi Liu
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Yinchu Ma
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Xinru Zhou
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Maoyuan Linghu
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Wen Xu
- Neurology Department, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Fei Gao
- Department of Critical Care Medicine, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi People’s Hospital, Wuxi Medical Center, Nanjing Medical University, Wuxi, China
| | - Yi Huang
- Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
- Insitute of Health and Medicine, Hefei Comprehensive National Science Center, Hefei, 230601 China
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4
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Qi J, Shi L, Zhu L, Chen Y, Zhu H, Cheng W, Chen AF, Fu C. Functions, Mechanisms, and therapeutic applications of the inositol pyrophosphates 5PP-InsP 5 and InsP 8 in mammalian cells. J Cardiovasc Transl Res 2024; 17:197-215. [PMID: 37615888 DOI: 10.1007/s12265-023-10427-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 08/14/2023] [Indexed: 08/25/2023]
Abstract
Water-soluble myo-inositol phosphates have long been characterized as second messengers. The signaling properties of these compounds are determined by the number and arrangement of phosphate groups on the myo-inositol backbone. Recently, higher inositol phosphates with pyrophosphate groups were recognized as signaling molecules. 5-Diphosphoinositol 1,2,3,4,6-pentakisphosphate (5PP-InsP5) is the most abundant isoform, constituting more than 90% of intracellular inositol pyrophosphates. 5PP-InsP5 can be further phosphorylated to 1,5-bisdiphosphoinositol 2,3,4,6-tetrakisphosphate (InsP8). These two molecules, 5PP-InsP5 and InsP8, are present in various subcellular compartments, where they participate in regulating diverse cellular processes such as cell death, energy homeostasis, and cytoskeletal dynamics. The synthesis and metabolism of inositol pyrophosphates are subjected to tight regulation, allowing for their highly specific functions. Blocking the 5PP-InsP5/InsP8 signaling pathway by inhibiting the biosynthesis of 5PP-InsP5 demonstrates therapeutic benefits in preclinical studies, and thus holds promise as a therapeutic approach for certain diseases treatment, such as metabolic disorders.
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Affiliation(s)
- Ji Qi
- Institute for Developmental and Regenerative Cardiovascular Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Linhui Shi
- Department of Critical Care Unit, Ningbo Medical Center Li Huili Hospital, Ningbo University, Ningbo, 315040, Zhejiang, China
| | - Limei Zhu
- Department of Trauma Orthopedics, Ningbo No.6 Hospital, Ningbo, 315040, China
| | - Yuanyuan Chen
- Institute for Developmental and Regenerative Cardiovascular Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Hong Zhu
- Department of Obstetrics and Gynecology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Weiwei Cheng
- Department of Nuclear Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Alex F Chen
- Institute for Developmental and Regenerative Cardiovascular Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
| | - Chenglai Fu
- Institute for Developmental and Regenerative Cardiovascular Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
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5
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Gu C, Li X, Zong G, Wang H, Shears SB. IP8: A quantitatively minor inositol pyrophosphate signaling molecule that punches above its weight. Adv Biol Regul 2024; 91:101002. [PMID: 38064879 DOI: 10.1016/j.jbior.2023.101002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 11/27/2023] [Indexed: 02/25/2024]
Abstract
The inositol pyrophosphates (PP-IPs) are specialized members of the wider inositol phosphate signaling family that possess functionally significant diphosphate groups. The PP-IPs exhibit remarkable functionally versatility throughout the eukaryotic kingdoms. However, a quantitatively minor PP-IP - 1,5 bisdiphosphoinositol tetrakisphosphate (1,5-IP8) - has received considerably less attention from the cell signalling community. The main purpose of this review is to summarize recently-published data which have now brought 1,5-IP8 into the spotlight, by expanding insight into the molecular mechanisms by which this polyphosphate regulates many fundamental biological processes.
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Affiliation(s)
- Chunfang Gu
- Inositol signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709 USA
| | - Xingyao Li
- Inositol signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709 USA
| | - Guangning Zong
- Inositol signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709 USA
| | - Huanchen Wang
- Inositol signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709 USA.
| | - Stephen B Shears
- Inositol signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709 USA.
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Heitmann T, Liao G, de León P, Ernst G, Buchler I, Wei H, Shlevkov E, Brown D, Fitzek M, Collier M, Smith DM, Barrow JC. Fragment-Based Screening Identifies New Quinazolinone-Based Inositol Hexakisphosphate Kinase (IP6K) Inhibitors. ACS Med Chem Lett 2023; 14:1760-1766. [PMID: 38116421 PMCID: PMC10726443 DOI: 10.1021/acsmedchemlett.3c00409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 12/21/2023] Open
Abstract
A high-throughput fragment-based screen has been employed to discover a series of quinazolinone inositol hexakisphosphate kinase (IP6K) inhibitors. IP6Ks have been studied for their role in glucose homeostasis, metabolic disease, fatty liver disease, chronic kidney disease, blood coagulation, neurological development, and psychiatric disease. IP6Ks phosphorylate inositol hexakisphosphate (IP6) to form pyrophosphate 5-diphospho-1,2,3,4,6-pentakisphosphate (IP7). Molecular docking studies and investigation of structure-activity relationships around the quinazolinone core resulted in compounds with submicromolar potency and interesting selectivity for IP6K1 versus the closely related IP6K2 and IP6K3 isoforms.
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Affiliation(s)
- Tyler Heitmann
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Gangling Liao
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Pablo de León
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Glen Ernst
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Ingrid Buchler
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Huijun Wei
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
- Department
of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
| | - Evgeny Shlevkov
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Dean Brown
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Boston, Massachusetts 02451, United States
| | - Martina Fitzek
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Alderley Park, Macclesfield SK10 4TG, U.K.
| | - Matthew Collier
- Hit
Discovery, Discovery Sciences, R&D, AstraZeneca, Alderley Park, Macclesfield SK10 4TG, U.K.
| | - David M. Smith
- Emerging
Innovations Unit, Discovery Sciences, R&D, AstraZeneca, Cambridge CB2 0AA, U.K.
| | - James C. Barrow
- Lieber
Institute for Brain Development, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
- Department
of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, United States
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7
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Arora N, Keshri AK, Kaur R, Rawat SS, Kumar R, Mishra A, Prasad A. Taenia solium excretory secretory proteins (ESPs) suppresses TLR4/AKT mediated ROS formation in human macrophages via hsa-miR-125. PLoS Negl Trop Dis 2023; 17:e0011858. [PMID: 38157380 PMCID: PMC10783723 DOI: 10.1371/journal.pntd.0011858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 01/11/2024] [Accepted: 12/12/2023] [Indexed: 01/03/2024] Open
Abstract
BACKGROUND Helminth infections are a global health menace affecting 24% of the world population. They continue to increase global disease burden as their unclear pathology imposes serious challenges to patient management. Neurocysticercosis is classified as neglected tropical disease and is caused by larvae of helminthic cestode Taenia solium. The larvae infect humans and localize in central nervous system and cause NCC; a leading etiological agent of acquired epilepsy in the developing world. The parasite has an intricate antigenic make-up and causes active immune suppression in the residing host. It communicates with the host via its secretome which is complex mixture of proteins also called excretory secretory products (ESPs). Understanding the ESPs interaction with host can identify therapeutic intervention hot spots. In our research, we studied the effect of T. solium ESPs on human macrophages and investigated the post-translation switch involved in its immunopathogenesis. METHODOLOGY T. solium cysts were cultured in vitro to get ESPs and used for treating human macrophages. These macrophages were studied for cellular signaling and miR expression and quantification at transcript and protein level. CONCLUSION We found that T. solium cyst ESPs treatment to human macrophages leads to activation of Th2 immune response. A complex cytokine expression by macrophages was also observed with both Th1 and Th2 cytokines in milieu. But, at the same time ESPs modulated the macrophage function by altering the host miR expression as seen with altered ROS activity, apoptosis and phagocytosis. This leads to activated yet compromised functional macrophages, which provides a niche to support parasite survival. Thus T. solium secretome induces Th2 phenomenon in macrophages which may promote parasite's survival and delay their recognition by host immune system.
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Affiliation(s)
- Naina Arora
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Anand K. Keshri
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Rimanpreet Kaur
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Suraj S. Rawat
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Rajiv Kumar
- Biotechnology Division, CSIR-Institute for Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Amit Prasad
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
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8
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Hostachy S, Wang H, Zong G, Franke K, Riley AM, Schmieder P, Potter BVL, Shears SB, Fiedler D. Fluorination Influences the Bioisostery of Myo-Inositol Pyrophosphate Analogs. Chemistry 2023; 29:e202302426. [PMID: 37773020 PMCID: PMC7615343 DOI: 10.1002/chem.202302426] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/14/2023] [Accepted: 09/28/2023] [Indexed: 09/30/2023]
Abstract
Inositol pyrophosphates (PP-IPs) are densely phosphorylated messenger molecules involved in numerous biological processes. PP-IPs contain one or two pyrophosphate group(s) attached to a phosphorylated myo-inositol ring. 5PP-IP5 is the most abundant PP-IP in human cells. To investigate the function and regulation by PP-IPs in biological contexts, metabolically stable analogs have been developed. Here, we report the synthesis of a new fluorinated phosphoramidite reagent and its application for the synthesis of a difluoromethylene bisphosphonate analog of 5PP-IP5 . Subsequently, the properties of all currently reported analogs were benchmarked using a number of biophysical and biochemical methods, including co-crystallization, ITC, kinase activity assays and chromatography. Together, the results showcase how small structural alterations of the analogs can have notable effects on their properties in a biochemical setting and will guide in the choice of the most suitable analog(s) for future investigations.
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Affiliation(s)
- Sarah Hostachy
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP)Robert-Rössle-Straße 1013125BerlinGermany
| | - Huanchen Wang
- Inositol Signaling GroupNational Institutes of HealthResearch Triangle ParkNorth Carolina27709USA
| | - Guangning Zong
- Inositol Signaling GroupNational Institutes of HealthResearch Triangle ParkNorth Carolina27709USA
| | - Katy Franke
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP)Robert-Rössle-Straße 1013125BerlinGermany
| | - Andrew M. Riley
- Medicinal Chemistry & Drug Discovery Department of PharmacologyUniversity of OxfordOxfordOX1 3QTUK
| | - Peter Schmieder
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP)Robert-Rössle-Straße 1013125BerlinGermany
| | - Barry V. L. Potter
- Medicinal Chemistry & Drug Discovery Department of PharmacologyUniversity of OxfordOxfordOX1 3QTUK
| | - Stephen B. Shears
- Inositol Signaling GroupNational Institutes of HealthResearch Triangle ParkNorth Carolina27709USA
| | - Dorothea Fiedler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP)Robert-Rössle-Straße 1013125BerlinGermany
- Institut für ChemieHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
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9
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Heitmann T, Barrow JC. The Role of Inositol Hexakisphosphate Kinase in the Central Nervous System. Biomolecules 2023; 13:1317. [PMID: 37759717 PMCID: PMC10526494 DOI: 10.3390/biom13091317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/23/2023] [Accepted: 08/26/2023] [Indexed: 09/29/2023] Open
Abstract
Inositol is a unique biological small molecule that can be phosphorylated or even further pyrophosphorylated on each of its six hydroxyl groups. These numerous phosphorylation states of inositol along with the kinases and phosphatases that interconvert them comprise the inositol phosphate signaling pathway. Inositol hexakisphosphate kinases, or IP6Ks, convert the fully mono-phosphorylated inositol to the pyrophosphate 5-IP7 (also denoted IP7). There are three isoforms of IP6K: IP6K1, 2, and 3. Decades of work have established a central role for IP6Ks in cell signaling. Genetic and pharmacologic manipulation of IP6Ks in vivo and in vitro has shown their importance in metabolic disease, chronic kidney disease, insulin signaling, phosphate homeostasis, and numerous other cellular and physiologic processes. In addition to these peripheral processes, a growing body of literature has shown the role of IP6Ks in the central nervous system (CNS). IP6Ks have a key role in synaptic vesicle regulation, Akt/GSK3 signaling, neuronal migration, cell death, autophagy, nuclear translocation, and phosphate homeostasis. IP6Ks' regulation of these cellular processes has functional implications in vivo in behavior and CNS anatomy.
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Affiliation(s)
- Tyler Heitmann
- Department of Pharmacology and Molecular Sciences, School of Medicine, Johns Hopkins University, 725 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
- The Lieber Institute for Brain Development, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
| | - James C. Barrow
- Department of Pharmacology and Molecular Sciences, School of Medicine, Johns Hopkins University, 725 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
- The Lieber Institute for Brain Development, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
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10
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Kobayashi A, Abe SI, Watanabe M, Moritoh Y. Liquid chromatography-mass spectrometry measurements of blood diphosphoinositol pentakisphosphate levels. J Chromatogr A 2022; 1681:463450. [DOI: 10.1016/j.chroma.2022.463450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/10/2022] [Accepted: 08/24/2022] [Indexed: 10/15/2022]
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11
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Li H, Datunashvili M, Reyes RC, Voglmaier SM. Inositol hexakisphosphate kinases differentially regulate trafficking of vesicular glutamate transporters 1 and 2. Front Cell Neurosci 2022; 16:926794. [PMID: 35936490 PMCID: PMC9355605 DOI: 10.3389/fncel.2022.926794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 06/27/2022] [Indexed: 11/16/2022] Open
Abstract
Inositol pyrophosphates have been implicated in cellular signaling and membrane trafficking, including synaptic vesicle (SV) recycling. Inositol hexakisphosphate kinases (IP6Ks) and their product, diphosphoinositol pentakisphosphate (PP-IP5 or IP7), directly and indirectly regulate proteins important in vesicle recycling by the activity-dependent bulk endocytosis pathway (ADBE). In the present study, we show that two isoforms, IP6K1 and IP6K3, are expressed in axons. The role of the kinases in SV recycling are investigated using pharmacologic inhibition, shRNA knockdown, and IP6K1 and IP6K3 knockout mice. Live-cell imaging experiments use optical reporters of SV recycling based on vesicular glutamate transporter isoforms, VGLUT1- and VGLUT2-pHluorins (pH), which recycle differently. VGLUT1-pH recycles by classical AP-2 dependent endocytosis under moderate stimulation conditions, while VGLUT2-pH recycles using AP-1 and AP-3 adaptor proteins as well. Using a short stimulus to release the readily releasable pool (RRP), we show that IP6K1 KO increases exocytosis of both VGLUT1-and VGLUT2-pH, while IP6K3 KO decreases the amount of both transporters in the RRP. In electrophysiological experiments we measure glutamate signaling with short stimuli and under the intense stimulation conditions that trigger bulk endocytosis. IP6K1 KO increases synaptic facilitation and IP6K3 KO decreases facilitation compared to wild type in CA1 hippocampal Schaffer collateral synapses. After intense stimulation, the rate of endocytosis of VGLUT2-pH, but not VGLUT1-pH, is increased by knockout, knockdown, and pharmacologic inhibition of IP6Ks. Thus IP6Ks differentially affect the endocytosis of two SV protein cargos that use different endocytic pathways. However, while IP6K1 KO and IP6K3 KO exert similar effects on endocytosis after stimulation, the isoforms exert different effects on exocytosis earlier in the stimulus and on the early phase of glutamate release. Taken together, the data indicate a role for IP6Ks both in exocytosis early in the stimulation period and in endocytosis, particularly under conditions that may utilize AP-1/3 adaptors.
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12
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Zhang F, Niu M, Wang L, Liu Y, Shi L, Cao J, Mi W, Ma Y, Liu J. Systemic-Immune-Inflammation Index as a Promising Biomarker for Predicting Perioperative Ischemic Stroke in Older Patients Who Underwent Non-cardiac Surgery. Front Aging Neurosci 2022; 14:865244. [PMID: 35431888 PMCID: PMC9010030 DOI: 10.3389/fnagi.2022.865244] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 03/07/2022] [Indexed: 12/27/2022] Open
Abstract
Objective This study aimed to investigate the clinical prognostic values of the preoperative systemic-immune-inflammation index (SII) in older patients undergoing non-cardiac surgery, using perioperative ischemic stroke as the primary outcome. Methods This retrospective cohort study included older patients who underwent non-cardiac surgery between January 2008 and August 2019. The patients were divided into SII < 583 and SII ≥ 583 group according to the optimal SII cut-off value. The outcome of interest was ischemic stroke within 30 days after surgery. Primary, sensitivity, and subgroup analyses were performed to confirm that preoperative SII qualifies as a promising, independent prognostic indicator. Propensity score matching (PSM) analysis was further applied to address the potential residual confounding effect of covariates to examine the robustness of our results. Results Among the 40,670 included patients with a median age of 70 years (interquartile range: 67, 74), 237 (0.58%) experienced an ischemic stroke within 30 days after surgery. SII ≥ 583 was associated with an increased risk of perioperative ischemic stroke in multivariate regression analysis [odds ratio (OR), 1.843; 95% confidence interval (CI), 1.369-2.480; P < 0.001]. After PSM adjustment, all covariates were well balanced between the two groups. The correlation between the SII and perioperative ischemic stroke remained significantly robust (OR: 2.195; 95% CI: 1.574-3.106; P < 0.001) in the PSM analysis. Conclusion Preoperative SII, which includes neutrophil, platelet, and lymphocyte counts obtained from routine blood analysis, was a potential prognostic biomarker for predicting perioperative ischemic stroke after non-cardiac surgery in elderly older patients. An elevated SII, based on an optimal cut-off value of 583, was an independent risk factor for perioperative ischemic stroke.
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Affiliation(s)
- Faqiang Zhang
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Mu Niu
- Department of Neurology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, Xuzhou, China
| | - Long Wang
- Department of Pain Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yanhong Liu
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Likai Shi
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Jiangbei Cao
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Weidong Mi
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yulong Ma
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China,*Correspondence: Yulong Ma,
| | - Jing Liu
- Anesthesia and Operation Center, The First Medical Center, Chinese PLA General Hospital, Beijing, China,Jing Liu,
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13
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Lee H, Park SJ, Hong S, Lim SW, Kim S. Deletion of IP6K1 in mice accelerates tumor growth by dysregulating the tumor-immune microenvironment. Anim Cells Syst (Seoul) 2022; 26:19-27. [PMID: 35308129 PMCID: PMC8928833 DOI: 10.1080/19768354.2022.2029560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A family of inositol hexakisphosphate kinases (IP6Ks) catalyzes the production of inositol pyrophosphate IP7 (5-diphosphoinositolpentakisphosphate) which is known to modulate various biological events such as cell growth. While targeting IP6K1 in various cancer cells has been well reported to control cancer cell motility and invasiveness, the role of host IP6K1 in tumor progression remains unknown. By using a syngeneic MC38 murine mouse colon carcinoma model, here we examined how host IP6K1 in the tumor microenvironment influences tumor growth. In IP6K1 knockout (KO) mice, the growth of MC38 tumor cells was markedly accelerated and host survival was significantly shortened compared with wild-type (WT). Our flow cytometric analysis revealed that tumors grown in IP6K1 KO mice had lower immune suppressive myeloid cells and M1 polarized macrophages. Notably, infiltration of both antigen-presenting dendritic cells and CD8+ cytotoxic T lymphocytes into the tumor tissues was remarkably abrogated in IP6K1 KO condition. These studies suggest that enhanced tumor growth in IP6K1 KO mice resulted from reduced anti-tumor immunity due to disturbed immune cell actions in the tumor microenvironment. In conclusion, we demonstrate that host IP6K1 acts as a tumor suppressor, most likely by fine-tuning diverse tumor-immune cell interactions, which might have implications for improving the host response against cancer progression.
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Affiliation(s)
- Haein Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seung Ju Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Sehoon Hong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seol-Wa Lim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for the BioCentury, KAIST, Daejeon, Republic of Korea
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14
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Yu S, Cai C, Zhang X, Sheng C, Jiang K. Method for the accurate determination of phytic acid in beverages by liquid chromatography-mass spectrometry after methylation with (trimethylsilyl) diazomethane. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Fan Y, Teng Y, Loison F, Pang A, Kasorn A, Shao X, Zhang C, Ren Q, Yu H, Zheng Y, Cancelas JA, Manis J, Chai L, Park SY, Zhao L, Xu Y, Feng S, Silberstein LE, Ma F, Luo HR. Targeting multiple cell death pathways extends the shelf life and preserves the function of human and mouse neutrophils for transfusion. Sci Transl Med 2021; 13:13/604/eabb1069. [PMID: 34321317 DOI: 10.1126/scitranslmed.abb1069] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/25/2021] [Accepted: 06/03/2021] [Indexed: 12/31/2022]
Abstract
Clinical outcomes from granulocyte transfusion (GTX) are disadvantaged by the short shelf life and compromised function of donor neutrophils. Spontaneous neutrophil death is heterogeneous and mediated by multiple pathways. Leveraging mechanistic knowledge and pharmacological screening, we identified a combined treatment, caspases-lysosomal membrane permeabilization-oxidant-necroptosis inhibition plus granulocyte colony-stimulating factor (CLON-G), which altered neutrophil fate by simultaneously targeting multiple cell death pathways. CLON-G prolonged human and mouse neutrophil half-life in vitro from less than 1 day to greater than 5 days. CLON-G-treated aged neutrophils had equivalent morphology and function to fresh neutrophils, with no impairment to critical effector functions including phagocytosis, bacterial killing, chemotaxis, and reactive oxygen species production. Transfusion with stored CLON-G-treated 3-day-old neutrophils enhanced host defenses, alleviated infection-induced tissue damage, and prolonged survival as effectively as transfusion with fresh neutrophils in a clinically relevant murine GTX model of neutropenia-related bacterial pneumonia and systemic candidiasis. Last, CLON-G treatment prolonged the shelf life and preserved the function of apheresis-collected human GTX products both ex vivo and in vivo in immunodeficient mice. Thus, CLON-G treatment represents an effective and applicable clinical procedure for the storage and application of neutrophils in transfusion medicine, providing a therapeutic strategy for improving GTX efficacy.
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Affiliation(s)
- Yuping Fan
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Yan Teng
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Fabien Loison
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Aiming Pang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Anongnard Kasorn
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Xinqi Shao
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Cunling Zhang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Qian Ren
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Hongbo Yu
- Department of Pathology and Laboratory Medicine, VA Boston Healthcare System, 1400 VFW Parkway, West Roxbury, MA 02132, USA
| | - Yi Zheng
- Experimental Hematology and Cancer Biology Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Jose A Cancelas
- Experimental Hematology and Cancer Biology Research, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.,Hoxworth Blood Center, Cincinnati, OH 45267, USA
| | - John Manis
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Li Chai
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Shin-Young Park
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Li Zhao
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Yuanfu Xu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Sizhou Feng
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Leslie E Silberstein
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA
| | - Fengxia Ma
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, CAMS Key Laboratory for Prevention and Control of Hematological Disease Treatment Related Infection, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China.
| | - Hongbo R Luo
- Joint Program in Transfusion Medicine, Department of Pathology, Harvard Medical School; Division of Blood Bank, Department of Laboratory Medicine, Stem Cell Program, Boston Children's Hospital; and Dana-Farber/Harvard Cancer Center, Boston, MA 02115, USA.
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16
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Badodi S, Pomella N, Zhang X, Rosser G, Whittingham J, Niklison-Chirou MV, Lim YM, Brandner S, Morrison G, Pollard SM, Bennett CD, Clifford SC, Peet A, Basson MA, Marino S. Inositol treatment inhibits medulloblastoma through suppression of epigenetic-driven metabolic adaptation. Nat Commun 2021; 12:2148. [PMID: 33846320 PMCID: PMC8042111 DOI: 10.1038/s41467-021-22379-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 03/12/2021] [Indexed: 12/11/2022] Open
Abstract
Deregulation of chromatin modifiers plays an essential role in the pathogenesis of medulloblastoma, the most common paediatric malignant brain tumour. Here, we identify a BMI1-dependent sensitivity to deregulation of inositol metabolism in a proportion of medulloblastoma. We demonstrate mTOR pathway activation and metabolic adaptation specifically in medulloblastoma of the molecular subgroup G4 characterised by a BMI1High;CHD7Low signature and show this can be counteracted by IP6 treatment. Finally, we demonstrate that IP6 synergises with cisplatin to enhance its cytotoxicity in vitro and extends survival in a pre-clinical BMI1High;CHD7Low xenograft model.
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Affiliation(s)
- Sara Badodi
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Nicola Pomella
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Xinyu Zhang
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Gabriel Rosser
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - John Whittingham
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
| | - Maria Victoria Niklison-Chirou
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
- Centre for Therapeutic Innovation (CTI-Bath), Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - Yau Mun Lim
- UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Sebastian Brandner
- UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Gillian Morrison
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Steven M Pollard
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Women and Children's Hospital, Birmingham, UK
| | - Steven C Clifford
- Newcastle University Centre for Cancer, Wolfson Childhood Cancer Research Centre, Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Andrew Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Women and Children's Hospital, Birmingham, UK
| | - M Albert Basson
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Silvia Marino
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
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17
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Minini M, Senni A, Unfer V, Bizzarri M. The Key Role of IP 6K: A Novel Target for Anticancer Treatments? Molecules 2020; 25:molecules25194401. [PMID: 32992691 PMCID: PMC7583815 DOI: 10.3390/molecules25194401] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/29/2022] Open
Abstract
Inositol and its phosphate metabolites play a pivotal role in several biochemical pathways and gene expression regulation: inositol pyrophosphates (PP-IPs) have been increasingly appreciated as key signaling modulators. Fluctuations in their intracellular levels hugely impact the transfer of phosphates and the phosphorylation status of several target proteins. Pharmacological modulation of the proteins associated with PP-IP activities has proved to be beneficial in various pathological settings. IP7 has been extensively studied and found to play a key role in pathways associated with PP-IP activities. Three inositol hexakisphosphate kinase (IP6K) isoforms regulate IP7 synthesis in mammals. Genomic deletion or enzymic inhibition of IP6K1 has been shown to reduce cell invasiveness and migration capacity, protecting against chemical-induced carcinogenesis. IP6K1 could therefore be a useful target in anticancer treatment. Here, we summarize the current understanding that established IP6K1 and the other IP6K isoforms as possible targets for cancer therapy. However, it will be necessary to determine whether pharmacological inhibition of IP6K is safe enough to begin clinical study. The development of safe and selective inhibitors of IP6K isoforms is required to minimize undesirable effects.
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Affiliation(s)
- Mirko Minini
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Department of Surgery ‘P. Valdoni’, Sapienza University of Rome, 00161 Rome, Italy
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.M.); (M.B.)
| | - Alice Senni
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Department of Surgery ‘P. Valdoni’, Sapienza University of Rome, 00161 Rome, Italy
| | - Vittorio Unfer
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
| | - Mariano Bizzarri
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy;
- Systems Biology Group Lab, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.M.); (M.B.)
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18
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Inositol Pyrophosphates: Signaling Molecules with Pleiotropic Actions in Mammals. Molecules 2020; 25:molecules25092208. [PMID: 32397291 PMCID: PMC7249018 DOI: 10.3390/molecules25092208] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/01/2020] [Accepted: 05/07/2020] [Indexed: 02/07/2023] Open
Abstract
Inositol pyrophosphates (PP-IPs) such as 5-diphosphoinositol pentakisphosphate (5-IP7) are inositol metabolites containing high-energy phosphoanhydride bonds. Biosynthesis of PP-IPs is mediated by IP6 kinases (IP6Ks) and PPIP5 kinases (PPIP5Ks), which transfer phosphate to inositol hexakisphosphate (IP6). Pleiotropic actions of PP-IPs are involved in many key biological processes, including growth, vesicular remodeling, and energy homeostasis. PP-IPs function to regulate their target proteins through allosteric interactions or protein pyrophosphorylation. This review summarizes the current understanding of how PP-IPs control mammalian cellular signaling networks in physiology and disease.
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19
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Mukherjee S, Haubner J, Chakraborty A. Targeting the Inositol Pyrophosphate Biosynthetic Enzymes in Metabolic Diseases. Molecules 2020; 25:molecules25061403. [PMID: 32204420 PMCID: PMC7144392 DOI: 10.3390/molecules25061403] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/12/2022] Open
Abstract
In mammals, a family of three inositol hexakisphosphate kinases (IP6Ks) synthesizes the inositol pyrophosphate 5-IP7 from IP6. Genetic deletion of Ip6k1 protects mice from high fat diet induced obesity, insulin resistance and fatty liver. IP6K1 generated 5-IP7 promotes insulin secretion from pancreatic β-cells, whereas it reduces insulin signaling in metabolic tissues by inhibiting the protein kinase Akt. Thus, IP6K1 promotes high fat diet induced hyperinsulinemia and insulin resistance in mice while its deletion has the opposite effects. IP6K1 also promotes fat accumulation in the adipose tissue by inhibiting the protein kinase AMPK mediated energy expenditure. Genetic deletion of Ip6k3 protects mice from age induced fat accumulation and insulin resistance. Accordingly, the pan IP6K inhibitor TNP [N2-(m-trifluorobenzyl), N6-(p-nitrobenzyl)purine] ameliorates obesity, insulin resistance and fatty liver in diet induced obese mice by improving Akt and AMPK mediated insulin sensitivity and energy expenditure. TNP also protects mice from bone loss, myocardial infarction and ischemia reperfusion injury. Thus, the IP6K pathway is a potential target in obesity and other metabolic diseases. Here, we summarize the studies that established IP6Ks as a potential target in metabolic diseases. Further studies will reveal whether inhibition of this pathway has similar pleiotropic benefits on metabolic health of humans.
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20
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Ganguli S, Shah A, Hamid A, Singh A, Palakurti R, Bhandari R. A high energy phosphate jump - From pyrophospho-inositol to pyrophospho-serine. Adv Biol Regul 2020; 75:100662. [PMID: 31668836 DOI: 10.1016/j.jbior.2019.100662] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 09/26/2019] [Accepted: 09/30/2019] [Indexed: 06/10/2023]
Abstract
Inositol pyrophosphates (PP-IPs) are a class of energy rich metabolites present in all eukaryotic cells. The hydroxyl groups on these water soluble derivatives of inositol are substituted with diphosphate and monophosphate moieties. Since the discovery of PP-IPs in the early 1990s, enormous progress has been made in uncovering pleiotropic roles for these small molecules in cellular physiology. PP-IPs exert their effect on proteins in two ways - allosteric regulation by direct binding, or post-translational regulation by serine pyrophosphorylation, a modification unique to PP-IPs. Serine pyrophosphorylation is achieved by Mg2+-dependent, but enzyme independent transfer of a β-phosphate from a PP-IP to a pre-phosphorylated serine residue located in an acidic motif, within an intrinsically disordered protein sequence. This distinctive post-translational modification has been shown to regulate diverse cellular processes, including rRNA synthesis, glycolysis, and vesicle transport. However, our understanding of the molecular details of this phosphotransfer from pyrophospho-inositol to generate pyrophospho-serine, is still nascent. This review discusses our current knowledge of protein pyrophosphorylation, and recent advances in understanding the mechanism of this important yet overlooked post-translational modification.
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Affiliation(s)
- Shubhra Ganguli
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Akruti Shah
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India; Manipal Academy of Higher Education, Manipal, 576104, India
| | - Aisha Hamid
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Arpita Singh
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Ravichand Palakurti
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500039, India.
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21
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Hou Q, Liu F, Chakraborty A, Jia Y, Prasad A, Yu H, Zhao L, Ye K, Snyder SH, Xu Y, Luo HR. Inhibition of IP6K1 suppresses neutrophil-mediated pulmonary damage in bacterial pneumonia. Sci Transl Med 2019; 10:10/435/eaal4045. [PMID: 29618559 DOI: 10.1126/scitranslmed.aal4045] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 11/16/2017] [Accepted: 02/12/2018] [Indexed: 01/07/2023]
Abstract
The significance of developing host-modulating personalized therapies to counteract the growing threat of antimicrobial resistance is well-recognized because such resistance cannot be overcome using microbe-centered strategies alone. Immune host defenses must be finely controlled during infection to balance pathogen clearance with unwanted inflammation-induced tissue damage. Thus, an ideal antimicrobial treatment would enhance bactericidal activity while preventing neutrophilic inflammation, which can induce tissue damage. We report that disrupting the inositol hexakisphosphate kinase 1 (Ip6k1) gene or pharmacologically inhibiting IP6K1 activity using the specific inhibitor TNP [N2-(m-(trifluoromethyl)benzyl) N6-(p-nitrobenzyl)purine] efficiently and effectively enhanced host bacterial killing but reduced pulmonary neutrophil accumulation, minimizing the lung damage caused by both Gram-positive and Gram-negative bacterial pneumonia. IP6K1-mediated inorganic polyphosphate (polyP) production by platelets was essential for infection-induced neutrophil-platelet aggregate (NPA) formation and facilitated neutrophil accumulation in alveolar spaces during bacterial pneumonia. IP6K1 inhibition reduced serum polyP levels, which regulated NPAs by triggering the bradykinin pathway and bradykinin-mediated neutrophil activation. Thus, we identified a mechanism that enhances host defenses while simultaneously suppressing neutrophil-mediated pulmonary damage in bacterial pneumonia. IP6K1 is, therefore, a legitimate therapeutic target for such disease.
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Affiliation(s)
- Qingming Hou
- Department of Pathology, Harvard Medical School, Dana-Farber/Harvard Cancer Center; Department of Laboratory Medicine, Children's Hospital Boston, Karp Family Research Building, Room 10214, Boston, MA 02115, USA
| | - Fei Liu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
| | - Anutosh Chakraborty
- Departments of Neuroscience, Pharmacology and Molecular Sciences, and Psychiatry, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yonghui Jia
- Department of Pathology, Harvard Medical School, Dana-Farber/Harvard Cancer Center; Department of Laboratory Medicine, Children's Hospital Boston, Karp Family Research Building, Room 10214, Boston, MA 02115, USA
| | - Amit Prasad
- Department of Pathology, Harvard Medical School, Dana-Farber/Harvard Cancer Center; Department of Laboratory Medicine, Children's Hospital Boston, Karp Family Research Building, Room 10214, Boston, MA 02115, USA
| | - Hongbo Yu
- Veterans Affairs Boston Healthcare System, Department of Pathology and Laboratory Medicine, 1400 Veterans of Foreign Wars Parkway, West Roxbury, MA 02132, USA
| | - Li Zhao
- Department of Pathology, Harvard Medical School, Dana-Farber/Harvard Cancer Center; Department of Laboratory Medicine, Children's Hospital Boston, Karp Family Research Building, Room 10214, Boston, MA 02115, USA
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Solomon H Snyder
- Departments of Neuroscience, Pharmacology and Molecular Sciences, and Psychiatry, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yuanfu Xu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China.
| | - Hongbo R Luo
- Department of Pathology, Harvard Medical School, Dana-Farber/Harvard Cancer Center; Department of Laboratory Medicine, Children's Hospital Boston, Karp Family Research Building, Room 10214, Boston, MA 02115, USA.
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Kim J, Darè E, Rajasekaran SS, Ryu SH, Berggren PO, Barker CJ. Inositol pyrophosphates and Akt/PKB: Is the pancreatic β-cell the exception to the rule? Cell Signal 2019; 58:131-136. [DOI: 10.1016/j.cellsig.2019.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 01/30/2019] [Accepted: 02/07/2019] [Indexed: 12/14/2022]
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23
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A novel fluorescent nanosensor based on small-sized conjugated polyelectrolyte dots for ultrasensitive detection of phytic acid. Talanta 2019; 202:214-220. [PMID: 31171173 DOI: 10.1016/j.talanta.2019.04.078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/21/2019] [Accepted: 04/28/2019] [Indexed: 11/23/2022]
Abstract
A novel nanosensor is developed for selective and highly sensitive detection of phytic acid (PA) based on small-sized conjugated polyelectrolyte dots (Pdots) fabricated from a new conjugated polymer (P1) by a modified reprecipitation method. P1 featuring a π-delocalized backbone bearing meta-substituted pyridyl groups can be endowed with enhanced flexibility and hence is beneficial for the synthesis of ultrasmall Pdots (i.e. Pdot-1, ∼3.8 nm in average diameter) as well as for the binding of Fe3+, thus leading to the obvious fluorescence quenching of Pdot-1 (∼444 nm) in the presence of Fe3+ via an electron transfer (ET) process. In addition, phytic acid with six phosphate groups exhibits strong chelating ability. When phytic acid is added, phytic acid readily binds to Fe3+ and the fluorescence of Pdot-1 around 444 nm can be recovered, rendering the supersensitive and selective sensing of PA. Under the optimum conditions, this ultra-small Pdot-based nanoprobe favors the fluorescent determination of PA with the detection limit as low as 10 nM. Particularly, Pdot-1 with bright blue fluorescence exhibits low cytotoxicity. Furthermore, the small-sized and biocompatible Pdot-1 can be applied to the sensitive fluorescence assay for PA in cell extracts and the efficient imaging of PA in live cells.
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24
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Trump LR, Nayak RC, Singh AK, Emberesh S, Wellendorf AM, Lutzko CM, Cancelas JA. Neutrophils Derived from Genetically Modified Human Induced Pluripotent Stem Cells Circulate and Phagocytose Bacteria In Vivo. Stem Cells Transl Med 2019; 8:557-567. [PMID: 30793529 PMCID: PMC6525559 DOI: 10.1002/sctm.18-0255] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 01/08/2019] [Indexed: 01/01/2023] Open
Abstract
Bacterial and fungal infections are a major cause of morbidity and mortality in neutropenic patients. Donor‐derived neutrophil transfusions have been used for prophylaxis or treatment for infection in neutropenic patients. However, the short half‐life and the limited availability of large numbers of donor‐derived neutrophils for transfusion remain a significant hurdle in the implementation of neutrophil transfusion therapy. Here, we investigate the in vitro and in vivo activity of neutrophils generated from human induced pluripotent stem cells (iPSC), a potentially unlimited resource to produce neutrophils for transfusion. Phenotypic analysis of iPSC‐derived neutrophils reveal reactive oxygen species production at similar or slightly higher than normal peripheral blood neutrophils, but have an ∼50%–70% reduced Escherichia coli phagocytosis and phorbol 12‐myristate 13‐acetate induced formation of neutrophil extracellular traps (NET). Signaling of granulocytic precursors identified impaired AKT activation, but not ERK or STAT3, in agonist‐stimulated iPSC‐derived neutrophils. Expression of a constitutively activated AKT in iPSC‐derived neutrophils restores most phagocytic activity and NET formation. In a model of bacterial induced peritonitis in immunodeficient mice, iPSC‐derived neutrophils, with or without corrected AKT activation, migrate similarly to the peritoneal fluid as peripheral blood neutrophils, whereas the expression of activated AKT significantly improves their phagocytic activity in vivo. stem cells translational medicine2019;8:557–567
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Affiliation(s)
- Lisa R Trump
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Ramesh C Nayak
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Abhishek K Singh
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Hoxworth Blood Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Sana Emberesh
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Ashley M Wellendorf
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Carolyn M Lutzko
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Hoxworth Blood Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Jose A Cancelas
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Hoxworth Blood Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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25
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Fu X, Halim A, Tian B, Luo Q, Song G. MT1-MMP downregulation via the PI3K/Akt signaling pathway is required for the mechanical stretching-inhibited invasion of bone-marrow-derived mesenchymal stem cells. J Cell Physiol 2019; 234:14133-14144. [PMID: 30659604 DOI: 10.1002/jcp.28105] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/07/2018] [Indexed: 12/21/2022]
Abstract
Mobilization from the bone marrow and the migration of bone-marrow-derived mesenchymal stem cells (BMSCs) through the peripheral circulation to injured tissue sites are regulated by multiple mechanical and chemical factors. We previously demonstrated that mechanical stretching promotes the migration but inhibits the invasion of BMSCs. However, the involved mechanisms, especially the mechanism of stretching-inhibited BMSC invasion, have not been thoroughly elucidated to date. In this study, we found that mechanical stretching with a 10% amplitude at a 1-Hz frequency for 8 hr significantly reduces BMSC invasion and downregulates the expression of membrane type-1 matrix metalloproteinases (MT1-MMP) at both the messenger RNA and protein levels. The overexpression of MT1-MMP restores mechanical stretching-reduced BMSC invasion. Moreover, phosphatidylinositol 3-kinase (PI3K)-dependent Akt phosphorylation in BMSCs was found to be inactivated by mechanical stretching. Pharmacological inhibitors of PI3K/Akt signaling (LY294002 or A443654) reduced the expression of MT1-MMP and impaired BMSC invasion. In addition, the upregulation of Akt phosphorylation by a pharmacological activator (SC79) increased MT1-MMP expression and suppressed mechanical stretching-reduced BMSC invasion. Taken together, our results suggest that mechanical stretching inhibits BMSC invasion by downregulating MT1-MMP expression by suppressing the PI3K/Akt signaling pathway.
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Affiliation(s)
- Xiaorong Fu
- Department of Bioengineering, College of Bioengineering, Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing, China
| | - Alexander Halim
- Department of Bioengineering, College of Bioengineering, Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing, China
| | - Boren Tian
- Department of Bioengineering, College of Bioengineering, Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing, China
| | - Qing Luo
- Department of Bioengineering, College of Bioengineering, Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing, China
| | - Guanbin Song
- Department of Bioengineering, College of Bioengineering, Chongqing University, Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing, China
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26
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Elich M, Sauer K. Regulation of Hematopoietic Cell Development and Function Through Phosphoinositides. Front Immunol 2018; 9:931. [PMID: 29780388 PMCID: PMC5945867 DOI: 10.3389/fimmu.2018.00931] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/16/2018] [Indexed: 01/01/2023] Open
Abstract
One of the most paramount receptor-induced signal transduction mechanisms in hematopoietic cells is production of the lipid second messenger phosphatidylinositol(3,4,5)trisphosphate (PIP3) by class I phosphoinositide 3 kinases (PI3K). Defective PIP3 signaling impairs almost every aspect of hematopoiesis, including T cell development and function. Limiting PIP3 signaling is particularly important, because excessive PIP3 function in lymphocytes can transform them and cause blood cancers. Here, we review the key functions of PIP3 and related phosphoinositides in hematopoietic cells, with a special focus on those mechanisms dampening PIP3 production, turnover, or function. Recent studies have shown that beyond “canonical” turnover by the PIP3 phosphatases and tumor suppressors phosphatase and tensin homolog (PTEN) and SH2 domain-containing inositol-5-phosphatase-1 (SHIP-1/2), PIP3 function in hematopoietic cells can also be dampened through antagonism with the soluble PIP3 analogs inositol(1,3,4,5)tetrakisphosphate (IP4) and inositol-heptakisphosphate (IP7). Other evidence suggests that IP4 can promote PIP3 function in thymocytes. Moreover, IP4 or the kinases producing it limit store-operated Ca2+ entry through Orai channels in B cells, T cells, and neutrophils to control cell survival and function. We discuss current models for how soluble inositol phosphates can have such diverse functions and can govern as distinct processes as hematopoietic stem cell homeostasis, neutrophil macrophage and NK cell function, and development and function of B cells and T cells. Finally, we will review the pathological consequences of dysregulated IP4 activity in immune cells and highlight contributions of impaired inositol phosphate functions in disorders such as Kawasaki disease, common variable immunodeficiency, or blood cancer.
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Affiliation(s)
- Mila Elich
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA, United States
| | - Karsten Sauer
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States.,Oncology R&D, Pfizer Worldwide R&D, San Diego, CA, United States
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27
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Chakraborty A. The inositol pyrophosphate pathway in health and diseases. Biol Rev Camb Philos Soc 2018; 93:1203-1227. [PMID: 29282838 PMCID: PMC6383672 DOI: 10.1111/brv.12392] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 11/28/2017] [Accepted: 12/05/2017] [Indexed: 12/11/2022]
Abstract
Inositol pyrophosphates (IPPs) are present in organisms ranging from plants, slime moulds and fungi to mammals. Distinct classes of kinases generate different forms of energetic diphosphate-containing IPPs from inositol phosphates (IPs). Conversely, polyphosphate phosphohydrolase enzymes dephosphorylate IPPs to regenerate the respective IPs. IPPs and/or their metabolizing enzymes regulate various cell biological processes by modulating many proteins via diverse mechanisms. In the last decade, extensive research has been conducted in mammalian systems, particularly in knockout mouse models of relevant enzymes. Results obtained from these studies suggest impacts of the IPP pathway on organ development, especially of brain and testis. Conversely, deletion of specific enzymes in the pathway protects mice from various diseases such as diet-induced obesity (DIO), type-2 diabetes (T2D), fatty liver, bacterial infection, thromboembolism, cancer metastasis and aging. Furthermore, pharmacological inhibition of the same class of enzymes in mice validates the therapeutic importance of this pathway in cardio-metabolic diseases. This review critically analyses these findings and summarizes the significance of the IPP pathway in mammalian health and diseases. It also evaluates benefits and risks of targeting this pathway in disease therapies. Finally, future directions of mammalian IPP research are discussed.
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Affiliation(s)
- Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, U.S.A
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28
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Brown NW, Marmelstein AM, Fiedler D. Chemical tools for interrogating inositol pyrophosphate structure and function. Chem Soc Rev 2018; 45:6311-6326. [PMID: 27462803 DOI: 10.1039/c6cs00193a] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The inositol pyrophosphates (PP-InsPs) are a unique group of intracellular messengers that represent some of the most highly phosphorylated molecules in nature. Genetic perturbation of the PP-InsP biosynthetic network indicates a central role for these metabolites in maintaining cellular energy homeostasis and in controlling signal transduction networks. However, despite their discovery over two decades ago, elucidating their physiologically relevant isomers, the biochemical pathways connecting these molecules to their associated phenotypes, and their modes of signal transduction has often been stymied by technical challenges. Many of the advances in understanding these molecules to date have been facilitated by the total synthesis of the various PP-InsP isomers and by the development of new methods that are capable of identifying their downstream signalling partners. Chemical tools have also been developed to distinguish between the proposed PP-InsP signal transduction mechanisms: protein binding, and a covalent modification of proteins termed protein pyrophosphorylation. In this article, we review these recent developments, discuss how they have helped to illuminate PP-InsP structure and function, and highlight opportunities for future discovery.
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Affiliation(s)
- Nathaniel W Brown
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
| | - Alan M Marmelstein
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
| | - Dorothea Fiedler
- Princeton University, Frick Chemistry Laboratory, Washington Road, Princeton, NJ 08544, USA and Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str 10, 13125 Berlin, Berlin, Germany.
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29
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Cordeiro CD, Saiardi A, Docampo R. The inositol pyrophosphate synthesis pathway in Trypanosoma brucei is linked to polyphosphate synthesis in acidocalcisomes. Mol Microbiol 2017; 106:319-333. [PMID: 28792096 DOI: 10.1111/mmi.13766] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2017] [Indexed: 12/19/2022]
Abstract
Inositol pyrophosphates are novel signaling molecules possessing high-energy pyrophosphate bonds and involved in a number of biological functions. Here, we report the correct identification and characterization of the kinases involved in the inositol pyrophosphate biosynthetic pathway in Trypanosoma brucei: inositol polyphosphate multikinase (TbIPMK), inositol pentakisphosphate 2-kinase (TbIP5K) and inositol hexakisphosphate kinase (TbIP6K). TbIP5K and TbIP6K were not identifiable by sequence alone and their activities were validated by enzymatic assays with the recombinant proteins or by their complementation of yeast mutants. We also analyzed T. brucei extracts for the presence of inositol phosphates using polyacrylamide gel electrophoresis and high-performance liquid chromatography. Interestingly, we could detect inositol phosphate (IP), inositol 4,5-bisphosphate (IP2 ), inositol 1,4,5-trisphosphate (IP3 ), and inositol hexakisphosphate (IP6 ) in T. brucei different stages. Bloodstream forms unable to produce inositol pyrophosphates, due to downregulation of TbIPMK expression by conditional knockout, have reduced levels of polyphosphate and altered acidocalcisomes. Our study links the inositol pyrophosphate pathway to the synthesis of polyphosphate in acidocalcisomes, and may lead to better understanding of these organisms and provide new targets for drug discovery.
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Affiliation(s)
- Ciro D Cordeiro
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Adolfo Saiardi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, WC1E 6BT, Gower Street, London, UK
| | - Roberto Docampo
- Department of Cellular Biology, and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
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30
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Shears SB. Intimate connections: Inositol pyrophosphates at the interface of metabolic regulation and cell signaling. J Cell Physiol 2017; 233:1897-1912. [PMID: 28542902 DOI: 10.1002/jcp.26017] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 05/18/2017] [Indexed: 12/11/2022]
Abstract
Inositol pyrophosphates are small, diffusible signaling molecules that possess the most concentrated three-dimensional array of phosphate groups in Nature; up to eight phosphates are crammed around a six-carbon inositol ring. This review discusses the physico-chemical properties of these unique molecules, and their mechanisms of action. Also provided is information on the enzymes that regulate the levels and hence the signaling properties of these molecules. This review pursues the idea that many of the biological effects of inositol pyrophosphates can be rationalized by their actions at the interface of cell signaling and metabolism that is essential to cellular and organismal homeostasis.
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Affiliation(s)
- Stephen B Shears
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina
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31
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Liu Z, Yago T, Zhang N, Panicker SR, Wang Y, Yao L, Mehta-D'souza P, Xia L, Zhu C, McEver RP. L-selectin mechanochemistry restricts neutrophil priming in vivo. Nat Commun 2017; 8:15196. [PMID: 28497779 PMCID: PMC5437312 DOI: 10.1038/ncomms15196] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 03/09/2017] [Indexed: 01/02/2023] Open
Abstract
Circulating neutrophils must avoid premature activation to prevent tissue injury. The leukocyte adhesion receptor L-selectin forms bonds with P-selectin glycoprotein ligand-1 (PSGL-1) on other leukocytes and with peripheral node addressin (PNAd) on high endothelial venules. Mechanical forces can strengthen (catch) or weaken (slip) bonds between biological molecules. How these mechanochemical processes influence function in vivo is unexplored. Here we show that mice expressing an L-selectin mutant (N138G) have altered catch bonds and prolonged bond lifetimes at low forces. Basal lymphocyte homing and neutrophil recruitment to inflamed sites are normal. However, circulating neutrophils form unstable aggregates and are unexpectedly primed to respond robustly to inflammatory mediators. Priming requires signals transduced through L-selectin N138G after it engages PSGL-1 or PNAd. Priming enhances bacterial clearance but increases inflammatory injury and enlarges venous thrombi. Thus, L-selectin mechanochemistry limits premature activation of neutrophils. Our results highlight the importance of probing how mechanochemistry functions in vivo. Neutrophil adhesion is tightly regulated to enforce protective immunity, but it is unclear how mechanochemical processes such as catch bonds and slip bonds modulate neutrophils in vivo. Here the authors show that a point mutation in the adhesion molecule L-selectin alters mechanochemical regulation to affect neutrophil functions in mice.
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Affiliation(s)
- Zhenghui Liu
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
| | - Tadayuki Yago
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
| | - Nan Zhang
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
| | - Sumith R Panicker
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
| | - Ying Wang
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
| | - Longbiao Yao
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
| | - Padmaja Mehta-D'souza
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
| | - Lijun Xia
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
| | - Cheng Zhu
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.,Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.,Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Rodger P McEver
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA.,Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
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32
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Dutta AK, Captain I, Jessen HJ. New Synthetic Methods for Phosphate Labeling. Top Curr Chem (Cham) 2017; 375:51. [DOI: 10.1007/s41061-017-0135-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 03/27/2017] [Indexed: 12/12/2022]
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33
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Shah A, Ganguli S, Sen J, Bhandari R. Inositol Pyrophosphates: Energetic, Omnipresent and Versatile Signalling Molecules. J Indian Inst Sci 2017; 97:23-40. [PMID: 32214696 PMCID: PMC7081659 DOI: 10.1007/s41745-016-0011-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 11/16/2016] [Indexed: 12/21/2022]
Abstract
Inositol pyrophosphates (PP-IPs) are a class of energy-rich signalling molecules found in all eukaryotic cells. These are derivatives of inositol that contain one or more diphosphate (or pyrophosphate) groups in addition to monophosphates. The more abundant and best studied PP-IPs are diphosphoinositol pentakisphosphate (IP7) and bis-diphosphoinositol tetrakisphosphate (IP8). These molecules can influence protein function by two mechanisms: binding and pyrophosphorylation. The former involves the specific interaction of a particular inositol pyrophosphate with a binding site on a protein, while the latter is a unique attribute of inositol pyrophosphates, wherein the β-phosphate moiety is transferred from a PP-IP to a pre-phosphorylated serine residue in a protein to generate pyrophosphoserine. Both these events can result in changes in the target protein’s activity, localisation or its interaction with other partners. As a consequence of their ubiquitous presence in all eukaryotic organisms and all cell types examined till date, and their ability to modify protein function, PP-IPs have been found to participate in a wide range of metabolic, developmental, and signalling pathways. This review highlights
many of the known functions of PP-IPs in the context of their temporal and spatial distribution in eukaryotic cells.
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Affiliation(s)
- Akruti Shah
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Shubhra Ganguli
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Jayraj Sen
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
- Graduate Studies, Manipal University, Manipal, Karnataka India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana India
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Abstract
To help define the molecular basis of cellular signalling cascades, and their biological functions, there is considerable value in utilizing a high-quality chemical 'probe' that has a well-defined interaction with a specific cellular protein. Such reagents include inhibitors of protein kinases and small molecule kinases, as well as mimics or antagonists of intracellular signals. The purpose of this review is to consider recent progress and promising future directions for the development of novel molecules that can interrogate and manipulate the cellular actions of inositol pyrophosphates (PP-IPs)--a specialized, 'energetic' group of cell-signalling molecules in which multiple phosphate and diphosphate groups are crammed around a cyclohexane polyol scaffold.
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35
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Shears SB, Baughman BM, Gu C, Nair VS, Wang H. The significance of the 1-kinase/1-phosphatase activities of the PPIP5K family. Adv Biol Regul 2016; 63:98-106. [PMID: 27776974 DOI: 10.1016/j.jbior.2016.10.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 10/13/2016] [Accepted: 10/15/2016] [Indexed: 01/29/2023]
Abstract
The inositol pyrophosphates (diphosphoinositol polyphosphates), which include 1-InsP7, 5-InsP7, and InsP8, are highly 'energetic' signaling molecules that play important roles in many cellular processes, particularly with regards to phosphate and bioenergetic homeostasis. Two classes of kinases synthesize the PP-InsPs: IP6Ks and PPIP5Ks. The significance of the IP6Ks - and their 5-InsP7 product - has been widely reported. However, relatively little is known about the biological significance of the PPIP5Ks. The purpose of this review is to provide an update on developments in our understanding of key features of the PPIP5Ks, which we believe strengthens the hypothesis that their catalytic activities serve important cellular functions. Central to this discussion is the recent discovery that the PPIP5K is a rare example of a single protein that catalyzes a kinase/phosphatase futile cycle.
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Affiliation(s)
- Stephen B Shears
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA.
| | - Brandi M Baughman
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Chunfang Gu
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Vasudha S Nair
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Huanchen Wang
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 101 T.W. Alexander Drive, Research Triangle Park, NC, 27709, USA
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36
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Zhu Q, Ghoshal S, Rodrigues A, Gao S, Asterian A, Kamenecka TM, Barrow JC, Chakraborty A. Adipocyte-specific deletion of Ip6k1 reduces diet-induced obesity by enhancing AMPK-mediated thermogenesis. J Clin Invest 2016; 126:4273-4288. [PMID: 27701146 DOI: 10.1172/jci85510] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 08/29/2016] [Indexed: 12/15/2022] Open
Abstract
Enhancing energy expenditure (EE) is an attractive strategy to combat obesity and diabetes. Global deletion of Ip6k1 protects mice from diet-induced obesity (DIO) and insulin resistance, but the tissue-specific mechanism by which IP6K1 regulates body weight is unknown. Here, we have demonstrated that IP6K1 regulates fat accumulation by modulating AMPK-mediated adipocyte energy metabolism. Cold exposure led to downregulation of Ip6k1 in murine inguinal and retroperitoneal white adipose tissue (IWAT and RWAT) depots. Adipocyte-specific deletion of Ip6k1 (AdKO) enhanced thermogenic EE, which protected mice from high-fat diet-induced weight gain at ambient temperature (23°C), but not at thermoneutral temperature (30°C). AdKO-induced increases in thermogenesis also protected mice from cold-induced decreases in body temperature. UCP1, PGC1α, and other markers of browning and thermogenesis were elevated in IWAT and RWAT of AdKO mice. Cold-induced activation of sympathetic signaling was unaltered, whereas AMPK was enhanced, in AdKO IWAT. Moreover, beige adipocytes from AdKO IWAT displayed enhanced browning, which was diminished by AMPK depletion. Furthermore, we determined that IP6 and IP6K1 differentially regulate upstream kinase-mediated AMPK stimulatory phosphorylation in vitro. Finally, treating mildly obese mice with the IP6K inhibitor TNP enhanced thermogenesis and inhibited progression of DIO. Thus, IP6K1 regulates energy metabolism via a mechanism that could potentially be targeted in obesity.
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Moritoh Y, Oka M, Yasuhara Y, Hozumi H, Iwachidow K, Fuse H, Tozawa R. Inositol Hexakisphosphate Kinase 3 Regulates Metabolism and Lifespan in Mice. Sci Rep 2016; 6:32072. [PMID: 27577108 PMCID: PMC5006000 DOI: 10.1038/srep32072] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 08/02/2016] [Indexed: 12/26/2022] Open
Abstract
Inositol hexakisphosphate kinase 3 (IP6K3) generates inositol pyrophosphates, which regulate diverse cellular functions. However, little is known about its own physiological role. Here, we show the roles of IP6K3 in metabolic regulation. We detected high levels of both mouse and human IP6K3 mRNA in myotubes and muscle tissues. In human myotubes, IP6K3 was upregulated by dexamethasone treatment, which is known to inhibit glucose metabolism. Furthermore, Ip6k3 expression was elevated under diabetic, fasting, and disuse conditions in mouse skeletal muscles. Ip6k3(-/-) mice demonstrated lower blood glucose, reduced circulating insulin, deceased fat mass, lower body weight, increased plasma lactate, enhanced glucose tolerance, lower glucose during an insulin tolerance test, and reduced muscle Pdk4 expression under normal diet conditions. Notably, Ip6k3 deletion extended animal lifespan with concomitant reduced phosphorylation of S6 ribosomal protein in the heart. In contrast, Ip6k3(-/-) mice showed unchanged skeletal muscle mass and no resistance to the effects of high fat diet. The current observations suggest novel roles of IP6K3 in cellular regulation, which impact metabolic control and lifespan.
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Affiliation(s)
- Yusuke Moritoh
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Masahiro Oka
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Yoshitaka Yasuhara
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hiroyuki Hozumi
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Kimihiko Iwachidow
- Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hiromitsu Fuse
- Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Ryuichi Tozawa
- Cardiovascular and Metabolic Drug Discovery Unit, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
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Ghoshal S, Zhu Q, Asteian A, Lin H, Xu H, Ernst G, Barrow JC, Xu B, Cameron MD, Kamenecka TM, Chakraborty A. TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine] ameliorates diet induced obesity and insulin resistance via inhibition of the IP6K1 pathway. Mol Metab 2016; 5:903-917. [PMID: 27689003 PMCID: PMC5034689 DOI: 10.1016/j.molmet.2016.08.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 08/10/2016] [Accepted: 08/15/2016] [Indexed: 12/30/2022] Open
Abstract
Objective Obesity and type 2 diabetes (T2D) lead to various life-threatening diseases such as coronary heart disease, stroke, osteoarthritis, asthma, and neurodegeneration. Therefore, extensive research is ongoing to identify novel pathways that can be targeted in obesity/T2D. Deletion of the inositol pyrophosphate (5-IP7) biosynthetic enzyme, inositol hexakisphosphate kinase-1 (IP6K1), protects mice from high fat diet (HFD) induced obesity (DIO) and insulin resistance. Yet, whether this pathway is a valid pharmacologic target in obesity/T2D is not known. Here, we demonstrate that TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine], a pan-IP6K inhibitor, has strong anti-obesity and anti-diabetic effects in DIO mice. Methods Q-NMR, GTT, ITT, food intake, energy expenditure, QRT-PCR, ELISA, histology, and immunoblot studies were conducted in short (2.5-week)- and long (10-week)-term TNP treated DIO C57/BL6 WT and IP6K1-KO mice, under various diet and temperature conditions. Results TNP, when injected at the onset of HFD-feeding, decelerates initiation of DIO and insulin resistance. Moreover, TNP facilitates weight loss and restores metabolic parameters, when given to DIO mice. However, TNP does not reduce weight gain in HFD-fed IP6K1-KO mice. TNP specifically enhances insulin sensitivity in DIO mice via Akt activation. TNP decelerates weight gain primarily by enhancing thermogenic energy expenditure in the adipose tissue. Accordingly, TNP's effect on body weight is partly abolished whereas its impact on glucose homeostasis is preserved at thermoneutral temperature. Conclusion Pharmacologic inhibition of the inositol pyrophosphate pathway has strong therapeutic potential in obesity, T2D, and other metabolic diseases. Pharmacologic inhibition of IP6K by TNP, at the onset of high fat feeding, decelerates initiation of DIO and insulin resistance in mice. TNP, when treated to DIO mice, promotes weight loss and restores metabolic homeostasis. TNP does not reduce high fat diet induced weight gain in IP6K1-KO mice. TNP promotes insulin sensitivity by stimulating Akt activity, whereas it reduces body weight primarily by enhancing thermogenic energy expenditure. Long-term TNP treatment does not display deleterious side effects.
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Key Words
- 5-IP7, diphosphoinositol pentakisphosphate
- ALT, alanine aminotransferase
- AST, aspartate transaminase
- AUC, area under curve
- Akt
- BAT, brown adipose tissue
- CD, chow-diet
- CPT1a, carnitine palmitoyltransferase I
- Cidea, cell death activator-A
- DIO, diet-induced obesity
- Diabetes
- EE, energy expenditure
- EWAT, epididymal adipose tissue
- Energy expenditure
- GSK3, glycogen synthase kinase
- GTT, glucose tolerance test
- H&E, hematoxylin and eosin
- HFD, high-fat diet
- HPLC, high performance liquid chromatography
- IP6K
- IP6K, Inositol hexakisphosphate kinase
- IP6K1-KO, IP6K1 knockout
- ITT, insulin tolerance test
- IWAT, inguinal adipose tissue
- Inositol pyrophosphate
- Obesity
- PCR, polymerase chain reaction
- PGC1α, PPAR coactivator 1 alpha
- PKA, protein kinase A
- PPARγ, peroxisome proliferator-activated receptor gamma
- PRDM16, PR domain containing 16
- Pro-TNP, TNP treatment for protection against DIO
- Q-NMR, quantitative nuclear magnetic resonance
- QRT-PCR, quantitative reverse transcription polymerase chain reaction
- RER, Respiratory exchange ratio
- RWAT, retroperitoneal adipose tissue
- Rev-TNP, long-term TNP treatment for reversal of DIO
- RevT-TNP, Long-term TNP treatment for reversal of DIO at thermoneutral temperature
- S473, serine 473
- S9, serine 9
- SREV-TNP, short-term TNP treatment for reversal of DIO
- T2D, type-2 diabetes
- T308, threonine 308
- TNP, [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine]
- UCP-1/3, uncoupling protein 1/3
- VO2, volume of oxygen consumption
- WAT, white adipose tissue
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Affiliation(s)
- Sarbani Ghoshal
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Qingzhang Zhu
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Alice Asteian
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Hua Lin
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Haifei Xu
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Glen Ernst
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, MD 21205, USA
| | - James C Barrow
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, MD 21205, USA
| | - Baoji Xu
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Michael D Cameron
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Theodore M Kamenecka
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Anutosh Chakraborty
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL 33458, USA.
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Inositol hexakisphosphate kinase-1 interacts with perilipin1 to modulate lipolysis. Int J Biochem Cell Biol 2016; 78:149-155. [PMID: 27373682 DOI: 10.1016/j.biocel.2016.06.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 05/20/2016] [Accepted: 06/28/2016] [Indexed: 12/21/2022]
Abstract
Lipolysis leads to the breakdown of stored triglycerides (TAG) to release free fatty acids (FFA) and glycerol which is utilized by energy expenditure pathways to generate energy. Therefore, a decrease in lipolysis augments fat accumulation in adipocytes which promotes weight gain. Conversely, if lipolysis is not complemented by energy expenditure, it leads to FFA induced insulin resistance and type-2 diabetes. Thus, lipolysis is under stringent physiological regulation, although the precise mechanism of the regulation is not known. Deletion of inositol hexakisphosphate kinase-1 (IP6K1), the major inositol pyrophosphate biosynthetic enzyme, protects mice from high fat diet (HFD) induced obesity and insulin resistance. IP6K1-KO mice are lean due to enhanced energy expenditure. Therefore, IP6K1 is a target in obesity and type-2 diabetes. However, the mechanism/s by which IP6K1 regulates adipose tissue lipid metabolism is yet to be understood. Here, we demonstrate that IP6K1-KO mice display enhanced basal lipolysis. IP6K1 modulates lipolysis via its interaction with the lipolytic regulator protein perilipin1 (PLIN1). Furthermore, phosphorylation of IP6K1 at a PKC/PKA motif modulates its interaction with PLIN1 and lipolysis. Thus, IP6K1 is a novel regulator of PLIN1 mediated lipolysis.
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Thota SG, Bhandari R. The emerging roles of inositol pyrophosphates in eukaryotic cell physiology. J Biosci 2016; 40:593-605. [PMID: 26333405 DOI: 10.1007/s12038-015-9549-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Inositol pyrophosphates are water soluble derivatives of inositol that contain pyrophosphate or diphosphate moieties in addition to monophosphates. The best characterised inositol pyrophosphates, are IP7 (diphosphoinositol pentakisphosphate or PP-IP5), and IP8 (bisdiphosphoinositol tetrakisphosphate or (PP)2-IP4). These energy-rich small molecules are present in all eukaryotic cells, from yeast to mammals, and are involved in a wide range of cellular functions including apoptosis, vesicle trafficking, DNA repair, osmoregulation, phosphate homeostasis, insulin sensitivity, immune signalling, cell cycle regulation, and ribosome synthesis. Identified more than 20 years ago, there is still only a rudimentary understanding of the mechanisms by which inositol pyrophosphates participate in these myriad pathways governing cell physiology and homeostasis. The unique stereochemical and bioenergetic properties these molecules possess as a consequence of the presence of one or two pyrophosphate moieties in the vicinity of densely packed monophosphates are likely to form the molecular basis for their participation in multiple signalling and metabolic pathways. The aim of this review is to provide first time researchers in this area with an introduction to inositol pyrophosphates and a comprehensive overview on their cellular functions.
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Affiliation(s)
- Swarna Gowri Thota
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500 001, India
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41
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Erneux C, Ghosh S, Koenig S. Inositol(1,4,5)P3 3-kinase isoenzymes: Catalytic properties and importance of targeting to F-actin to understand function. Adv Biol Regul 2016; 60:135-143. [PMID: 26446452 DOI: 10.1016/j.jbior.2015.09.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 09/10/2015] [Accepted: 09/10/2015] [Indexed: 06/05/2023]
Abstract
Inositol(1,4,5)trisphosphate (Ins(1,4,5)P3) 3-kinases (Itpks) catalyze the phosphorylation of inositol(1,4,5)trisphosphate into inositol(1,3,4,5)tetrakisphosphate (Ins(1,3,4,5)P4). Three isoenzymes Itpka/b and c have been identified in human, rat and mouse. They share a catalytic domain relatively well conserved at the C-terminal end and a quite isoenzyme specific regulatory domain at the N-terminal end of the protein. Activity determined in cell homogenates with Ins(1,4,5)P3 and ATP as substrate is generally very low compared to Ins(1,4,5)P3 5-phosphatase, except in a few tissues such as brain, testis, thymus or intestine. Activity is very much Ca(2+) sensitive and increased in the presence of Ca(2+)/calmodulin (CaM) as compared to EGTA alone. When challenged after receptor activation, activity could be further activated several fold, e.g. in rat brain cortical slices stimulated by carbachol or in human astrocytoma cells stimulated by purinergic agonists. Two of the three isoenzymes show an unexpected cytoskeletal localization for Itpka/b or at the leading edge for Itpkb. This is explained by the presence of an F-actin binding site at the N-terminal part of the two isoenzymes. This interaction confers to Itpka the properties of an F-actin bundling protein with two major consequences: i) it can reorganize the cytoskeletal network, particularly in dendritic spines, and ii) can provide an opportunity for Ins(1,3,4,5)P4 to act very locally as second messenger.
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Affiliation(s)
- Christophe Erneux
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Bldg C, 808 Route de Lennik, 1070 Brussels, Belgium.
| | - Somadri Ghosh
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Bldg C, 808 Route de Lennik, 1070 Brussels, Belgium
| | - Sandra Koenig
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Campus Erasme, Bldg C, 808 Route de Lennik, 1070 Brussels, Belgium
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Extracellular Acidification Acts as a Key Modulator of Neutrophil Apoptosis and Functions. PLoS One 2015; 10:e0137221. [PMID: 26340269 PMCID: PMC4560393 DOI: 10.1371/journal.pone.0137221] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 08/14/2015] [Indexed: 11/19/2022] Open
Abstract
In human pathological conditions, the acidification of local environment is a frequent feature, such as tumor and inflammation. As the pH of microenvironment alters, the functions of immune cells are about to change. It makes the extracellular acidification a key modulator of innate immunity. Here we detected the impact of extracellular acidification on neutrophil apoptosis and functions, including cell death, respiratory burst, migration and phagocytosis. As a result, we found that under the acid environment, neutrophil apoptosis delayed, respiratory burst inhibited, polarization augmented, chemotaxis differed, endocytosis enhanced and bacteria killing suppressed. These findings suggested that extracellular acidification acts as a key regulator of neutrophil apoptosis and functions.
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Riley AM, Wang H, Shears SB, L. Potter BV. Synthetic tools for studying the chemical biology of InsP8. Chem Commun (Camb) 2015; 51:12605-8. [PMID: 26153667 PMCID: PMC4643724 DOI: 10.1039/c5cc05017k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 07/03/2015] [Indexed: 12/28/2022]
Abstract
To synthesise stabilised mimics of InsP8, the most phosphorylated inositol phosphate signalling molecule in Nature, we replaced its two diphosphate (PP) groups with either phosphonoacetate (PA) or methylenebisphosphonate (PCP) groups. Utility of the PA and PCP analogues was verified by structural and biochemical analyses of their interactions with enzymes of InsP8 metabolism.
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Affiliation(s)
- Andrew M. Riley
- Wolfson Laboratory of Medicinal Chemistry , Department of Pharmacy and Pharmacology , University of Bath , Claverton Down , Bath , BA2 7AY , UK
| | - Huanchen Wang
- Inositol Signaling Group , Laboratory of Signal Transduction , National Institute of Environmental Health Sciences , National Institutes of Health , Research Triangle Park , North Carolina , USA
| | - Stephen B. Shears
- Inositol Signaling Group , Laboratory of Signal Transduction , National Institute of Environmental Health Sciences , National Institutes of Health , Research Triangle Park , North Carolina , USA
| | - Barry V. L. Potter
- Wolfson Laboratory of Medicinal Chemistry , Department of Pharmacy and Pharmacology , University of Bath , Claverton Down , Bath , BA2 7AY , UK
- Department of Pharmacology , University of Oxford , Mansfield Road , Oxford , OX1 3QT , UK . ; Fax: +44-1865-271853 ; Tel: +44-1865-271945
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44
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Wang X, Hills LB, Huang YH. Lipid and Protein Co-Regulation of PI3K Effectors Akt and Itk in Lymphocytes. Front Immunol 2015; 6:117. [PMID: 25821452 PMCID: PMC4358224 DOI: 10.3389/fimmu.2015.00117] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/02/2015] [Indexed: 12/21/2022] Open
Abstract
The phosphoinositide 3-kinase (PI 3-kinase, PI3K) pathway transduces signals critical for lymphocyte function. PI3K generates the phospholipid PIP3 at the plasma membrane to recruit proteins that contain pleckstrin homology (PH) domains – a conserved domain found in hundreds of mammalian proteins. PH domain–PIP3 interactions allow for rapid signal propagation and confer a spatial component to these signals. The kinases Akt and Itk are key PI3K effectors that bind PIP3 via their PH domains and mediate vital processes – such as survival, activation, and differentiation – in lymphocytes. Here, we review the roles and regulation of PI3K signaling in lymphocytes with a specific emphasis on Akt and Itk. We also discuss these and other PH domain-containing proteins as they relate more broadly to immune cell function. Finally, we highlight the emerging view of PH domains as multifunctional protein domains that often bind both lipid and protein substrates to exert their effects.
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Affiliation(s)
- Xinxin Wang
- California Institute for Biomedical Research , La Jolla, CA , USA
| | - Leonard Benjamin Hills
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA
| | - Yina Hsing Huang
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA ; Department of Pathology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA
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Williams SP, Gillaspy GE, Perera IY. Biosynthesis and possible functions of inositol pyrophosphates in plants. FRONTIERS IN PLANT SCIENCE 2015; 6:67. [PMID: 25729385 PMCID: PMC4325660 DOI: 10.3389/fpls.2015.00067] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/26/2015] [Indexed: 05/24/2023]
Abstract
Inositol phosphates (InsPs) are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5) bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e., PPx) attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration of cellular metabolism and stress signaling in non-plant eukaryotes. Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid). Even though plants produce huge amounts of precursor InsP6 in seeds, almost no attention has been paid to whether PPx-InsPs exist in plants, and if so, what roles these molecules play. Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom. This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.
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Affiliation(s)
- Sarah P. Williams
- Biochemistry, Virginia Polytechnic and State UniversityBlacksburg, VA, USA
| | - Glenda E. Gillaspy
- Biochemistry, Virginia Polytechnic and State UniversityBlacksburg, VA, USA
| | - Imara Y. Perera
- Plant and Microbial Biology, North Carolina State UniversityRaleigh, NC, USA
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46
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Conway JH, Fiedler D. An Affinity Reagent for the Recognition of Pyrophosphorylated Peptides. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201411232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Conway JH, Fiedler D. An affinity reagent for the recognition of pyrophosphorylated peptides. Angew Chem Int Ed Engl 2015; 54:3941-5. [PMID: 25651128 DOI: 10.1002/anie.201411232] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Indexed: 11/05/2022]
Abstract
A resin-bound dinuclear zinc(II) complex for the selective capture of pyrophosphopeptides is reported. The metal complex binds diphosphate esters over other anionic groups, such as monophosphate esters, sulfate esters, and carboxylic acids, with high specificity. Immobilization of the compound provided a reagent capable of binding and retaining nanomolar quantities of pyrophosphopeptide in the presence of cell lysate. The high affinity and specificity of the reagent makes it an attractive tool for the study of in vivo pyrophosphorylation.
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Affiliation(s)
- John H Conway
- Department of Chemistry, Princeton University, Washington Rd, Princeton, NJ 08544 (USA)
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48
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Yates LM, Fiedler D. Establishing the Stability and Reversibility of Protein Pyrophosphorylation with Synthetic Peptides. Chembiochem 2015; 16:415-23. [DOI: 10.1002/cbic.201402589] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Indexed: 12/24/2022]
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Abstract
Neutrophils play critical roles in innate immunity and host defense. However, excessive neutrophil accumulation or hyper-responsiveness of neutrophils can be detrimental to the host system. Thus, the response of neutrophils to inflammatory stimuli needs to be tightly controlled. Many cellular processes in neutrophils are mediated by localized formation of an inositol phospholipid, phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3), at the plasma membrane. The PtdIns(3,4,5)P3 signaling pathway is negatively regulated by lipid phosphatases and inositol phosphates, which consequently play a critical role in controlling neutrophil function and would be expected to act as ideal therapeutic targets for enhancing or suppressing innate immune responses. Here, we comprehensively review current understanding about the action of lipid phosphatases and inositol phosphates in the control of neutrophil function in infection and inflammation.
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Affiliation(s)
- Hongbo R Luo
- Department of Pathology, Harvard Medical School, Boston, MA, USA Department of Lab Medicine, Children's Hospital Boston, Dana-Farber/Harvard Cancer Center, Boston, MA, USA
| | - Subhanjan Mondal
- Department of Pathology, Harvard Medical School, Boston, MA, USA Department of Lab Medicine, Children's Hospital Boston, Dana-Farber/Harvard Cancer Center, Boston, MA, USA Promega Corporation, Madison, WI, USA
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50
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PI3K signalling in inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:882-97. [PMID: 25514767 DOI: 10.1016/j.bbalip.2014.12.006] [Citation(s) in RCA: 341] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/24/2014] [Accepted: 12/09/2014] [Indexed: 12/13/2022]
Abstract
PI3Ks regulate several key events in the inflammatory response to damage and infection. There are four Class I PI3K isoforms (PI3Kα,β,γ,δ), three Class II PI3K isoforms (PI3KC2α, C2β, C2γ) and a single Class III PI3K. The four Class I isoforms synthesise the phospholipid 'PIP3'. PIP3 is a 'second messenger' used by many different cell surface receptors to control cell movement, growth, survival and differentiation. These four isoforms have overlapping functions but each is adapted to receive efficient stimulation by particular receptor sub-types. PI3Kγ is highly expressed in leukocytes and plays a particularly important role in chemokine-mediated recruitment and activation of innate immune cells at sites of inflammation. PI3Kδ is also highly expressed in leukocytes and plays a key role in antigen receptor and cytokine-mediated B and T cell development, differentiation and function. Class III PI3K synthesises the phospholipid PI3P, which regulates endosome-lysosome trafficking and the induction of autophagy, pathways involved in pathogen killing, antigen processing and immune cell survival. Much less is known about the function of Class II PI3Ks, but emerging evidence indicates they can synthesise PI3P and PI34P2 and are involved in the regulation of endocytosis. The creation of genetically-modified mice with altered PI3K signalling, together with the development of isoform-selective, small-molecule PI3K inhibitors, has allowed the evaluation of the individual roles of Class I PI3K isoforms in several mouse models of chronic inflammation. Selective inhibition of PI3Kδ, γ or β has each been shown to reduce the severity of inflammation in one or more models of autoimmune disease, respiratory disease or allergic inflammation, with dual γ/δ or β/δ inhibition generally proving more effective. The inhibition of Class I PI3Ks may therefore offer a therapeutic opportunity to treat non-resolving inflammatory pathologies in humans. This article is part of a Special Issue entitled Phosphoinositides.
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