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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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2
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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: 4] [Impact Index Per Article: 4.0] [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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Mukherjee S, Chakraborty M, Haubner J, Ernst G, DePasquale M, Carpenter D, Barrow JC, Chakraborty A. The IP6K Inhibitor LI-2242 Ameliorates Diet-Induced Obesity, Hyperglycemia, and Hepatic Steatosis in Mice by Improving Cell Metabolism and Insulin Signaling. Biomolecules 2023; 13:868. [PMID: 37238737 PMCID: PMC10216446 DOI: 10.3390/biom13050868] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Obesity and nonalcoholic fatty liver disease (NAFLD) are global health concerns, and thus, drugs for the long-term treatment of these diseases are urgently needed. We previously discovered that the inositol pyrophosphate biosynthetic enzyme IP6K1 is a target in diet-induced obesity (DIO), insulin resistance, and NAFLD. Moreover, high-throughput screening (HTS) assays and structure-activity relationship (SAR) studies identified LI-2242 as a potent IP6K inhibitor compound. Here, we tested the efficacy of LI-2242 in DIO WT C57/BL6J mice. LI-2242 (20 mg/kg/BW daily, i.p.) reduced body weight in DIO mice by specifically reducing the accumulation of body fat. It also improved glycemic parameters and reduced hyperinsulinemia. LI-2242-treated mice displayed reduced the weight of various adipose tissue depots and an increased expression of metabolism- and mitochondrial-energy-oxidation-inducing genes in these tissues. LI-2242 also ameliorated hepatic steatosis by reducing the expression of genes that enhance lipid uptake, lipid stabilization, and lipogenesis. Furthermore, LI-2242 enhances the mitochondrial oxygen consumption rate (OCR) and insulin signaling in adipocytes and hepatocytes in vitro. In conclusion, the pharmacologic inhibition of the inositol pyrophosphate pathway by LI-2242 has therapeutic potential in obesity and NAFLD.
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Affiliation(s)
- Sandip Mukherjee
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
| | - Molee Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
| | - Jake Haubner
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
| | - Glen Ernst
- Lieber Institute for Brain Development and Department of Pharmacology, Johns Hopkins University School of Medicine, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
| | - Michael DePasquale
- Lieber Institute for Brain Development and Department of Pharmacology, Johns Hopkins University School of Medicine, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
| | - Danielle Carpenter
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
| | - James C. Barrow
- Lieber Institute for Brain Development and Department of Pharmacology, Johns Hopkins University School of Medicine, 855 North Wolfe Street Suite 300, Baltimore, MD 21205, USA
| | - Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
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Fedeli V, Catizone A, Querqui A, Unfer V, Bizzarri M. The Role of Inositols in the Hyperandrogenic Phenotypes of PCOS: A Re-Reading of Larner’s Results. Int J Mol Sci 2023; 24:ijms24076296. [PMID: 37047265 PMCID: PMC10093919 DOI: 10.3390/ijms24076296] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/22/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023] Open
Abstract
Polycystic ovarian syndrome (PCOS) is the most common endocrinological disorder in women, in which, besides chronic anovulation/oligomenorrhea and ovarian cysts, hyperandrogenism plays a critical role in a large fraction of subjects. Inositol isomers—myo-Inositol and D-Chiro-Inositol—have recently been pharmacologically effective in managing many PCOS symptoms while rescuing ovarian fertility. However, some disappointing clinical results prompted the reconsideration of their specific biological functions. Surprisingly, D-Chiro-Ins stimulates androgen synthesis and decreases the ovarian estrogen pathway; on the contrary, myo-Ins activates FSH response and aromatase activity, finally mitigating ovarian hyperandrogenism. However, when the two isomers are given in association—according to the physiological ratio of 40:1—patients could benefit from myo-Ins enhanced FSH and estrogen responsiveness, while taking advantage of the insulin-sensitizing effects displayed mostly by D-Chiro-Ins. We need not postulate insulin resistance to explain PCOS pathogenesis, given that insulin hypersensitivity is likely a shared feature of PCOS ovaries. Indeed, even in the presence of physiological insulin stimulation, the PCOS ovary synthesizes D-Chiro-Ins four times more than that measured in control theca cells. The increased D-Chiro-Ins within the ovary is detrimental in preserving steroidogenic control, and this failure can easily explain why treatment strategies based upon high D-Chiro-Ins have been recognized as poorly effective. Within this perspective, two factors emerge as major determinants in PCOS: hyperandrogenism and reduced aromatase expression. Therefore, PCOS could no longer be considered a disease only due to increased androgen synthesis without considering the contemporary downregulation of aromatase and FSH receptors. Furthermore, these findings suggest that inositols can be specifically effective only for those PCOS phenotypes featured by hyperandrogenism.
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Ganekal P, Vastrad B, Kavatagimath S, Vastrad C, Kotrashetti S. Bioinformatics and Next-Generation Data Analysis for Identification of Genes and Molecular Pathways Involved in Subjects with Diabetes and Obesity. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:medicina59020309. [PMID: 36837510 PMCID: PMC9967176 DOI: 10.3390/medicina59020309] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/19/2023] [Accepted: 01/29/2023] [Indexed: 02/10/2023]
Abstract
Background and Objectives: A subject with diabetes and obesity is a class of the metabolic disorder. The current investigation aimed to elucidate the potential biomarker and prognostic targets in subjects with diabetes and obesity. Materials and Methods: The next-generation sequencing (NGS) data of GSE132831 was downloaded from Gene Expression Omnibus (GEO) database. Functional enrichment analysis of DEGs was conducted with ToppGene. The protein-protein interactions network, module analysis, target gene-miRNA regulatory network and target gene-TF regulatory network were constructed and analyzed. Furthermore, hub genes were validated by receiver operating characteristic (ROC) analysis. A total of 872 DEGs, including 439 up-regulated genes and 433 down-regulated genes were observed. Results: Second, functional enrichment analysis showed that these DEGs are mainly involved in the axon guidance, neutrophil degranulation, plasma membrane bounded cell projection organization and cell activation. The top ten hub genes (MYH9, FLNA, DCTN1, CLTC, ERBB2, TCF4, VIM, LRRK2, IFI16 and CAV1) could be utilized as potential diagnostic indicators for subjects with diabetes and obesity. The hub genes were validated in subjects with diabetes and obesity. Conclusion: This investigation found effective and reliable molecular biomarkers for diagnosis and prognosis by integrated bioinformatics analysis, suggesting new and key therapeutic targets for subjects with diabetes and obesity.
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Affiliation(s)
- Prashanth Ganekal
- Department of General Medicine, Basaveshwara Medical College, Chitradurga 577501, Karnataka, India
| | - Basavaraj Vastrad
- Department of Pharmaceutical Chemistry, K.L.E. College of Pharmacy, Gadag 582101, Karnataka, India
| | - Satish Kavatagimath
- Department of Pharmacognosy, K.L.E. College of Pharmacy, Belagavi 590010, Karnataka, India
| | - Chanabasayya Vastrad
- Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad 580001, Karnataka, India
- Correspondence: ; Tel.: +91-9480073398
| | - Shivakumar Kotrashetti
- Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad 580001, Karnataka, India
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Ito M, Fujii N, Kohara S, Hori S, Tanaka M, Wittwer C, Kikuchi K, Iijima T, Kakimoto Y, Hirabayashi K, Kurotaki D, Jessen HJ, Saiardi A, Nagata E. Inositol pyrophosphate profiling reveals regulatory roles of IP6K2-dependent enhanced IP 7 metabolism in the enteric nervous system. J Biol Chem 2023; 299:102928. [PMID: 36681123 PMCID: PMC9957762 DOI: 10.1016/j.jbc.2023.102928] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/06/2023] [Accepted: 01/07/2023] [Indexed: 01/20/2023] Open
Abstract
Inositol pyrophosphates regulate diverse physiological processes; to better understand their functional roles, assessing their tissue-specific distribution is important. Here, we profiled inositol pyrophosphate levels in mammalian organs using an originally designed liquid chromatography-mass spectrometry (LC-MS) protocol and discovered that the gastrointestinal tract (GIT) contained the highest levels of diphosphoinositol pentakisphosphate (IP7) and its precursor inositol hexakisphosphate (IP6). Although their absolute levels in the GIT are diet dependent, elevated IP7 metabolism still exists under dietary regimens devoid of exogenous IP7. Of the major GIT cells, enteric neurons selectively express the IP7-synthesizing enzyme IP6K2. We found that IP6K2-knockout mice exhibited significantly impaired IP7 metabolism in the various organs including the proximal GIT. In addition, our LC-MS analysis displayed that genetic ablation of IP6K2 significantly impaired IP7 metabolism in the gut and duodenal muscularis externa containing myenteric plexus. Whole transcriptome analysis of duodenal muscularis externa further suggested that IP6K2 inhibition significantly altered expression levels of the gene sets associated with mature neurons, neural progenitor/stem cells, and glial cells, as well as of certain genes modulating neuronal differentiation and functioning, implying critical roles of the IP6K2-IP7 axis in developmental and functional regulation of the enteric nervous system. These results collectively reveal an unexpected role of mammalian IP7-a highly active IP6K2-IP7 pathway is conducive to the enteric nervous system.
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Affiliation(s)
- Masatoshi Ito
- Support Center for Medical Research and Education, Tokai University, Isehara, Japan.
| | - Natsuko Fujii
- Department of Neurology, Tokai University School of Medicine, Isehara, Japan
| | - Saori Kohara
- Department of Neurology, Tokai University School of Medicine, Isehara, Japan
| | - Shuho Hori
- Support Center for Medical Research and Education, Tokai University, Isehara, Japan
| | - Masayuki Tanaka
- Support Center for Medical Research and Education, Tokai University, Isehara, Japan
| | | | - Kenta Kikuchi
- Laboratory of Chromatin Organization in Immune Cell Development, International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takatoshi Iijima
- Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Japan
| | - Yu Kakimoto
- Department of Forensic Medicine, Tokai University School of Medicine, Isehara, Japan
| | - Kenichi Hirabayashi
- Department of Pathology, Tokai University School of Medicine, Isehara, Japan
| | - Daisuke Kurotaki
- Laboratory of Chromatin Organization in Immune Cell Development, International Research Center for Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Henning J Jessen
- Institute of Organic Chemistry, University of Freiburg, Freiburg, Germany
| | - Adolfo Saiardi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Eiichiro Nagata
- Department of Neurology, Tokai University School of Medicine, Isehara, Japan.
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Yang S, Jin S, Xian H, Zhao Z, Wang L, Wu Y, Zhou L, Li M, Cui J. Metabolic enzyme UAP1 mediates IRF3 pyrophosphorylation to facilitate innate immune response. Mol Cell 2023; 83:298-313.e8. [PMID: 36603579 DOI: 10.1016/j.molcel.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/25/2022] [Accepted: 12/09/2022] [Indexed: 01/06/2023]
Abstract
Post-translational modifications (PTMs) of proteins are crucial to guarantee the proper biological functions in immune responses. Although protein phosphorylation has been extensively studied, our current knowledge of protein pyrophosphorylation, which occurs based on phosphorylation, is very limited. Protein pyrophosphorylation is originally considered to be a non-enzymatic process, and its function in immune signaling is unknown. Here, we identify a metabolic enzyme, UDP-N-acetylglucosamine pyrophosphorylase 1 (UAP1), as a pyrophosphorylase for protein serine pyrophosphorylation, by catalyzing the pyrophosphorylation of interferon regulatory factor 3 (IRF3) at serine (Ser) 386 to promote robust type I interferon (IFN) responses. Uap1 deficiency significantly impairs the activation of both DNA- and RNA-viruse-induced type I IFN pathways, and the Uap1-deficient mice are highly susceptible to lethal viral infection. Our findings demonstrate the function of protein pyrophosphorylation in the regulation of antiviral responses and provide insights into the crosstalk between metabolism and innate immunity.
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Affiliation(s)
- Shuai Yang
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Shouheng Jin
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Huifang Xian
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Department of Gastroenterology, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Zhiyao Zhao
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Department of Gastroenterology, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Liqiu Wang
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yaoxing Wu
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Liang Zhou
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Mengqiu Li
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jun Cui
- Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
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TNP Analogues Inhibit the Virulence Promoting IP3-4 Kinase Arg1 in the Fungal Pathogen Cryptococcus neoformans. Biomolecules 2022; 12:biom12101526. [PMID: 36291735 PMCID: PMC9599641 DOI: 10.3390/biom12101526] [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] [Received: 09/26/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/29/2022] Open
Abstract
New antifungals with unique modes of action are urgently needed to treat the increasing global burden of invasive fungal infections. The fungal inositol polyphosphate kinase (IPK) pathway, comprised of IPKs that convert IP3 to IP8, provides a promising new target due to its impact on multiple, critical cellular functions and, unlike in mammalian cells, its lack of redundancy. Nearly all IPKs in the fungal pathway are essential for virulence, with IP3-4 kinase (IP3-4K) the most critical. The dibenzylaminopurine compound, N2-(m-trifluorobenzylamino)-N6-(p-nitrobenzylamino)purine (TNP), is a commercially available inhibitor of mammalian IPKs. The ability of TNP to be adapted as an inhibitor of fungal IP3-4K has not been investigated. We purified IP3-4K from the human pathogens, Cryptococcus neoformans and Candida albicans, and optimised enzyme and surface plasmon resonance (SPR) assays to determine the half inhibitory concentration (IC50) and binding affinity (KD), respectively, of TNP and 38 analogues. A novel chemical route was developed to efficiently prepare TNP analogues. TNP and its analogues demonstrated inhibition of recombinant IP3-4K from C. neoformans (CnArg1) at low µM IC50s, but not IP3-4K from C. albicans (CaIpk2) and many analogues exhibited selectivity for CnArg1 over the human equivalent, HsIPMK. Our results provide a foundation for improving potency and selectivity of the TNP series for fungal IP3-4K.
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Boregowda SV, Nanjappa MK, Booker CN, Strivelli J, Supper VM, Cooke PS, Phinney DG. Pharmacological Inhibition of Inositol Hexakisphosphate Kinase 1 Protects Mice against Obesity-Induced Bone Loss. BIOLOGY 2022; 11:biology11091257. [PMID: 36138736 PMCID: PMC9495776 DOI: 10.3390/biology11091257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022]
Abstract
Obesity and type II diabetes mellitus (T2DM) are prominent risk factors for secondary osteoporosis due to the negative impacts of hyperglycemia and excessive body fat on bone metabolism. While the armamentarium of anti-diabetic drugs is expanding, their negative or unknown impacts on bone metabolism limits effectiveness. The inactivation of inositol hexakisphosphate kinase 1 (IP6K1) protects mice from high-fat-diet (HFD)-induced obesity (DIO) and insulin resistance by enhancing thermogenic energy expenditure, but the role of this kinase and the consequences of its inhibition on bone metabolism are unknown. To determine if IP6K1 inhibition in obese mice affords protection against obesity-induced metabolic derangements and bone loss, we maintained 2-month-old mice on a normal chow control diet or HFD under thermal neutral conditions for 100 d. Beginning on day 40, HFD-fed mice were divided into two groups and administered daily injections of vehicle or the pan-IP6K inhibitor TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl) purine]. HFD-fed mice developed obesity, hyperglycemia, hyperlipidemia, and secondary osteoporosis, while TNP administration protected mice against HFD-induced metabolic and lipid derangements and preserved bone mass, mineral density, and trabecular microarchitecture, which correlated with reduced serum leptin levels, reduced marrow adiposity, and preservation of marrow resident skeletal stem/progenitor cells (SSPCs). TNP also exhibited hypotensive activity, an unrealized benefit of the drug, and its prolonged administration had no adverse impacts on spermatogenesis. Together, these data indicate that the inhibition of IP6K1 using selective inhibitors, such as TNP, may provide an effective strategy to manage obesity and T2DM due to its bone sparing effects.
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Affiliation(s)
- Siddaraju V. Boregowda
- Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | | | - Cori N. Booker
- Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Jacqueline Strivelli
- Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Valentina M. Supper
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32610, USA
| | - Paul S. Cooke
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Donald G. Phinney
- Department of Molecular Medicine, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
- Correspondence:
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Daryadel A, Haykir B, Küng CJ, Bugarski M, Bettoni C, Schnitzbauer U, Hernando N, Hall AM, Wagner CA. Acute adaptation of renal phosphate transporters in the murine kidney to oral phosphate intake requires multiple signals. Acta Physiol (Oxf) 2022; 235:e13815. [PMID: 35334154 DOI: 10.1111/apha.13815] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 12/01/2022]
Abstract
AIMS Dietary inorganic phosphate (Pi) modulates renal Pi reabsorption by regulating the expression of the NaPi-IIa and NaPi-IIc Pi transporters. Here, we aimed to clarify the role of several Pi-regulatory mechanisms including parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23) and inositol hexakisphosphate kinases (IP6-kinases) in the acute regulation of NaPi-IIa and NaPi-IIc. METHODS Wildtype (WT) and PTH-deficient mice (PTH-KO) with/without inhibition of FGF23 signalling were gavaged with Pi/saline and examined at 1, 4 and 12 h. RESULTS Pi-gavage elevated plasma Pi and decreased plasma Ca2+ in both genotypes after 1 h Within 1 h, Pi-gavage decreased NaPi-IIa abundance in WT and PTH-KO mice. NaPi-IIc was downregulated 1 h post-administration in WT and after 4 h in PTH-KO. PTH increased after 1 h in WT animals. After 4 h Pi-gavage, FGF23 increased in both genotypes being higher in the KO group. PTHrp and dopamine were not altered by Pi-gavage. Blocking FGF23 signalling blunted PTH upregulation in WT mice and reduced NaPi-IIa downregulation in PTH-KO mice 4 h after Pi-gavage. Inhibition of IP6-kinases had no effect. CONCLUSIONS (1) Acute downregulation of renal Pi transporters in response to Pi intake occurs also in the absence of PTH and FGF23 signalling, (2) when FGF23 signalling is blocked, a partial contribution of PTH is revealed, (3) IP6 kinases, intracellular Pi-sensors in yeast and bacteria, are not involved, and (4) Acute Pi does not alter PTHrp and dopamine. Thus, signals other than PTH, PTHrp, FGF23 and dopamine contribute to renal adaption.
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Affiliation(s)
- Arezoo Daryadel
- Institute of Physiology University of Zürich Zürich Switzerland
- National Center of Competence in Research Kidney.CH Zürich Switzerland
| | - Betül Haykir
- Institute of Physiology University of Zürich Zürich Switzerland
| | | | - Milica Bugarski
- National Center of Competence in Research Kidney.CH Zürich Switzerland
- Institute of Anatomy University of Zürich Zürich Switzerland
| | - Carla Bettoni
- Institute of Physiology University of Zürich Zürich Switzerland
| | | | - Nati Hernando
- Institute of Physiology University of Zürich Zürich Switzerland
| | - Andrew M. Hall
- National Center of Competence in Research Kidney.CH Zürich Switzerland
- Institute of Anatomy University of Zürich Zürich Switzerland
| | - Carsten A. Wagner
- Institute of Physiology University of Zürich Zürich Switzerland
- National Center of Competence in Research Kidney.CH Zürich Switzerland
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Zhou Y, Mukherjee S, Huang D, Chakraborty M, Gu C, Zong G, Stashko MA, Pearce KH, Shears SB, Chakraborty A, Wang H, Wang X. Development of Novel IP6K Inhibitors for the Treatment of Obesity and Obesity-Induced Metabolic Dysfunctions. J Med Chem 2022; 65:6869-6887. [PMID: 35467861 PMCID: PMC9383042 DOI: 10.1021/acs.jmedchem.2c00220] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Obesity and obesity-induced metabolic dysfunctions are significant risk factors for nonalcoholic fatty liver disease and cardiovascular diseases. Thus, obesity is an economic and social burden in developed countries. Blocking the synthesis of inositol pyrophosphates by inositol hexakisphosphate kinase (IP6K) has been identified as a potential therapeutic strategy for obesity and related diseases. We have developed a novel and potent IP6K inhibitor 20 (UNC7467) (IC50 values: IP6K1 8.9 nM; IP6K2 4.9 nM; IP6K3 1320 nM). Inositol phosphate profiling of the HCT116 colon cancer cell line demonstrates that 20 reduced levels of inositol pyrophosphates by 66-81%, without significantly perturbing levels of other inositol phosphates. Furthermore, intraperitoneal injection of 20 in diet-induced obese mice improved glycemic profiles, ameliorated hepatic steatosis, and reduced weight gain without altering food intake. Thus, inhibitor 20 can be used as an in vivo probe for IP6K-related research. Moreover, it may have therapeutic relevance in treating obesity and related diseases.
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Affiliation(s)
- Yubai Zhou
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Sandip Mukherjee
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, M370, Schwitalla Hall, 1402 South Grand Boulevard, Saint Louis, Missouri 63104, United States
| | - Daowei Huang
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Molee Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, M370, Schwitalla Hall, 1402 South Grand Boulevard, Saint Louis, Missouri 63104, United States
| | - Chunfang Gu
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, United States
| | - Guangning Zong
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, United States
| | - Michael A Stashko
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Kenneth H Pearce
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Stephen B Shears
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, United States
| | - Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, M370, Schwitalla Hall, 1402 South Grand Boulevard, Saint Louis, Missouri 63104, United States
| | - Huanchen Wang
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, United States
| | - Xiaodong Wang
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.,Lineberger Comprehensive Cancer Center, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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12
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Whole Body Ip6k1 Deletion Protects Mice from Age-Induced Weight Gain, Insulin Resistance and Metabolic Dysfunction. Int J Mol Sci 2022; 23:ijms23042059. [PMID: 35216174 PMCID: PMC8878859 DOI: 10.3390/ijms23042059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/05/2022] [Accepted: 02/10/2022] [Indexed: 12/21/2022] Open
Abstract
(1) Background: We previously demonstrated that disruption of IP6K1 improves metabolism, protecting mice from high-fat diet-induced obesity, insulin resistance, and non-alcoholic fatty liver disease and steatohepatitis. Age-induced metabolic dysfunction is a major risk factor for metabolic diseases. The involvement of IP6K1 in this process is unknown. (2) Methods: Here, we compared body and fat mass, insulin sensitivity, energy expenditure and serum-, adipose tissue- and liver-metabolic parameters of chow-fed, aged, wild type (aWT) and whole body Ip6k1 knockout (aKO) mice. (3) Results: IP6K1 was upregulated in the adipose tissue and liver of aWT mice compared to young WT mice. Moreover, Ip6k1 deletion blocked age-induced increase in body- and fat-weight and insulin resistance in mice. aKO mice oxidized carbohydrates more efficiently. The knockouts displayed reduced levels of serum insulin, triglycerides, and non-esterified fatty acids. Ip6k1 deletion partly protected age-induced decline of the thermogenic uncoupling protein UCP1 in inguinal white adipose tissue. Targets inhibited by IP6K1 activity such as the insulin sensitivity- and energy expenditure-inducing protein kinases, protein kinase B (PKB/Akt) and AMP-activated protein kinase (AMPK), were activated in the adipose tissue and liver of aKO mice. (4) Conclusions: Ip6k1 deletion maintains healthy metabolism in aging and thus, targeting this kinase may delay the development of age-induced metabolic dysfunction.
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13
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Lee S, Park BB, Kwon H, Kim V, Jeon JS, Lee R, Subedi M, Lim T, Ha H, An D, Kim J, Kim D, Kim SK, Kim S, Byun Y. TNP and its analogs: Modulation of IP6K and CYP3A4 inhibition. J Enzyme Inhib Med Chem 2021; 37:269-279. [PMID: 34894957 PMCID: PMC8667942 DOI: 10.1080/14756366.2021.2000404] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Inositol hexakisphosphate kinase (IP6K) is an important mammalian enzyme involved in various biological processes such as insulin signalling and blood clotting. Recent analyses on drug metabolism and pharmacokinetic properties on TNP (N2-(m-trifluorobenzyl), N6-(p-nitrobenzyl)purine), a pan-IP6K inhibitor, have suggested that it may inhibit cytochrome P450 (CYP450) enzymes and induce unwanted drug-drug interactions in the liver. In this study, we confirmed that TNP inhibits CYP3A4 in type I binding mode more selectively than the other CYP450 isoforms. In an effort to find novel purine-based IP6K inhibitors with minimal CYP3A4 inhibition, we designed and synthesised 15 TNP analogs. Structure-activity relationship and biochemical studies, including ADP-Glo kinase assay and quantification of cell-based IP7 production, showed that compound 9 dramatically reduced CYP3A4 inhibition while retaining IP6K-inhibitory activity. Compound 9 can be a tool molecule for structural optimisation of purine-based IP6K inhibitors.
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Affiliation(s)
- Seulgi Lee
- Department of Biological Sciences, KAIST, Daejeon, South Korea
| | | | - Hongmok Kwon
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Vitchan Kim
- Department of Biological Sciences, Konkuk University, Seoul, South Korea
| | - Jang Su Jeon
- College of Pharmacy, Chungnam National University, Daejeon, South Korea
| | - Rowoon Lee
- Department of Biological Sciences, Konkuk University, Seoul, South Korea
| | - Milan Subedi
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Taehyeong Lim
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Hyunsoo Ha
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Dongju An
- Department of Biological Sciences, KAIST, Daejeon, South Korea
| | - Jaehoon Kim
- Department of Biological Sciences, KAIST, Daejeon, South Korea
| | - Donghak Kim
- Department of Biological Sciences, Konkuk University, Seoul, South Korea
| | - Sang Kyum Kim
- College of Pharmacy, Chungnam National University, Daejeon, South Korea
| | - Seyun Kim
- Department of Biological Sciences, KAIST, Daejeon, South Korea.,KAIST Institute for the BioCentury, KAIST, Daejeon, South Korea
| | - Youngjoo Byun
- Department of Biological Sciences, KAIST, Daejeon, South Korea.,Biomedical Research Center, Korea University Guro Hospital, Seoul, South Korea
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14
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Mukherjee S, Chakraborty M, Ulmasov B, McCommis K, Zhang J, Carpenter D, Msengi EN, Haubner J, Guo C, Pike DP, Ghoshal S, Ford DA, Neuschwander-Tetri BA, Chakraborty A. Pleiotropic actions of IP6K1 mediate hepatic metabolic dysfunction to promote nonalcoholic fatty liver disease and steatohepatitis. Mol Metab 2021; 54:101364. [PMID: 34757046 PMCID: PMC8609165 DOI: 10.1016/j.molmet.2021.101364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/11/2021] [Accepted: 10/23/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE Obesity and insulin resistance greatly increase the risk of nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH). We have previously discovered that whole-body and adipocyte-specific Ip6k1deletion protects mice from high-fat-diet-induced obesity and insulin resistance due to improved adipocyte thermogenesis and insulin signaling. Here, we aimed to determine the impact of hepatocyte-specific and whole-body Ip6k1 deletion (HKO and Ip6k1-KO or KO) on liver metabolism and NAFLD/NASH. METHODS Body weight and composition; energy expenditure; glycemic profiles; and serum and liver metabolic, inflammatory, fibrotic and toxicity parameters were assessed in mice fed Western and high-fructose diet (HFrD) (WD: 40% kcal fat, 1.25% cholesterol, no added choline and HFrD: 60% kcal fructose). Mitochondrial oxidative capacity was evaluated in isolated hepatocytes. RNA-Seq was performed in liver samples. Livers from human NASH patients were analyzed by immunoblotting and mass spectrometry. RESULTS HKO mice displayed increased hepatocyte mitochondrial oxidative capacity and improved insulin sensitivity but were not resistant to body weight gain. Improved hepatocyte metabolism partially protected HKO mice from NAFLD/NASH. In contrast, enhanced whole-body metabolism and reduced body fat accumulation significantly protected whole-body Ip6k1-KO mice from NAFLD/NASH. Mitochondrial oxidative pathways were upregulated, whereas gluconeogenic and fibrogenic pathways were downregulated in Ip6k1-KO livers. Furthermore, IP6K1 was upregulated in human NASH livers and interacted with the enzyme O-GlcNAcase that reduces protein O-GlcNAcylation. Protein O-GlcNAcylation was found to be reduced in Ip6k1-KO and HKO mouse livers. CONCLUSION Pleiotropic actions of IP6K1 in the liver and other metabolic tissues mediate hepatic metabolic dysfunction and NAFLD/NASH, and thus IP6K1 deletion may be a potential treatment target for this disease.
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Affiliation(s)
- Sandip Mukherjee
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Molee Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Barbara Ulmasov
- Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Kyle McCommis
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Jinsong Zhang
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Danielle Carpenter
- Department of Pathology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Eliwaza Naomi Msengi
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Jake Haubner
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Chun Guo
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Daniel P Pike
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Sarbani Ghoshal
- Department of Biological Sc. and Geology, QCC-CUNY, Bayside, NY, USA
| | - David A Ford
- Department of Biochemistry, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Brent A Neuschwander-Tetri
- Division of Gastroenterology and Hepatology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA
| | - Anutosh Chakraborty
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, Saint Louis, MO, 63104, USA.
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15
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Kröber T, Bartsch SM, Fiedler D. Pharmacological tools to investigate inositol polyphosphate kinases - Enzymes of increasing therapeutic relevance. Adv Biol Regul 2021; 83:100836. [PMID: 34802993 DOI: 10.1016/j.jbior.2021.100836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 10/27/2021] [Accepted: 10/28/2021] [Indexed: 01/01/2023]
Abstract
Inositol poly- and pyrophosphates (InsPs and PP-InsPs) are a group of central eukaryotic metabolites and signaling molecules. Due to the diverse cellular functions and widespread diseases InsPs and PP-InsPs are associated with, pharmacological targeting of the kinases involved in their biosynthesis has become a significant research interest in the last decade. In particular, the development of inhibitors for inositol hexakisphosphate kinases (IP6Ks) has leaped forward, while other inositol phosphate kinases have received scant attention. This review summarizes the efforts undertaken so far for discovering potent and selective inhibitors for this diverse group of small molecule kinases. The benefits of pharmacological inhibition are highlighted, given the multiple kinase-independent functions of inositol phosphate kinases. The distinct structural families of InsP and PP-InsP kinases are presented, and we discuss how compound availability for different inositol phosphate kinase families varies drastically. Lead compound discovery and optimization for the inositol kinases would benefit from detailed structural information on the ATP-binding sites of these kinases, as well as reliable biochemical and cellular read-outs to monitor inositol phosphate kinase activity in complex settings. Efforts to further tune well-established inhibitors, while simultaneously reviving tool compound development for the more neglected kinases from this family are indisputably worthwhile, considering the large potential therapeutic benefits.
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Affiliation(s)
- Tim Kröber
- Leibniz Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125, Berlin, Germany; Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Straße 2, 12489, Berlin, Germany.
| | - Simon M Bartsch
- Leibniz Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125, Berlin, Germany; Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Straße 2, 12489, Berlin, Germany.
| | - Dorothea Fiedler
- Leibniz Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125, Berlin, Germany; Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Straße 2, 12489, Berlin, Germany.
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16
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Pessoa Rodrigues C, Chatterjee A, Wiese M, Stehle T, Szymanski W, Shvedunova M, Akhtar A. Histone H4 lysine 16 acetylation controls central carbon metabolism and diet-induced obesity in mice. Nat Commun 2021; 12:6212. [PMID: 34707105 PMCID: PMC8551339 DOI: 10.1038/s41467-021-26277-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 09/21/2021] [Indexed: 12/26/2022] Open
Abstract
Noncommunicable diseases (NCDs) account for over 70% of deaths world-wide. Previous work has linked NCDs such as type 2 diabetes (T2D) to disruption of chromatin regulators. However, the exact molecular origins of these chronic conditions remain elusive. Here, we identify the H4 lysine 16 acetyltransferase MOF as a critical regulator of central carbon metabolism. High-throughput metabolomics unveil a systemic amino acid and carbohydrate imbalance in Mof deficient mice, manifesting in T2D predisposition. Oral glucose tolerance testing (OGTT) reveals defects in glucose assimilation and insulin secretion in these animals. Furthermore, Mof deficient mice are resistant to diet-induced fat gain due to defects in glucose uptake in adipose tissue. MOF-mediated H4K16ac deposition controls expression of the master regulator of glucose metabolism, Pparg and the entire downstream transcriptional network. Glucose uptake and lipid storage can be reconstituted in MOF-depleted adipocytes in vitro by ectopic Glut4 expression, PPARγ agonist thiazolidinedione (TZD) treatment or SIRT1 inhibition. Hence, chronic imbalance in H4K16ac promotes a destabilisation of metabolism triggering the development of a metabolic disorder, and its maintenance provides an unprecedented regulatory epigenetic mechanism controlling diet-induced obesity.
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Affiliation(s)
- Cecilia Pessoa Rodrigues
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, 79104, Freiburg, Germany
- International Max Planck Research School for Molecular and Cellular Biology (IMPRS-MCB), Freiburg, Germany
| | - Aindrila Chatterjee
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
- European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Meike Wiese
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | - Thomas Stehle
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | - Witold Szymanski
- Proteomics Facility, Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Maria Shvedunova
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | - Asifa Akhtar
- Department of Chromatin Regulation, Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany.
- Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, 79104, Freiburg, Germany.
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17
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Moritoh Y, Abe SI, Akiyama H, Kobayashi A, Koyama R, Hara R, Kasai S, Watanabe M. The enzymatic activity of inositol hexakisphosphate kinase controls circulating phosphate in mammals. Nat Commun 2021; 12:4847. [PMID: 34381031 PMCID: PMC8358040 DOI: 10.1038/s41467-021-24934-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 07/15/2021] [Indexed: 12/20/2022] Open
Abstract
Circulating phosphate levels are tightly controlled within a narrow range in mammals. By using a novel small-molecule inhibitor, we show that the enzymatic activity of inositol hexakisphosphate kinases (IP6K) is essential for phosphate regulation in vivo. IP6K inhibition suppressed XPR1, a phosphate exporter, thereby decreasing cellular phosphate export, which resulted in increased intracellular ATP levels. The in vivo inhibition of IP6K decreased plasma phosphate levels without inhibiting gut intake or kidney reuptake of phosphate, demonstrating a pivotal role of IP6K-regulated cellular phosphate export on circulating phosphate levels. IP6K inhibition-induced decrease in intracellular inositol pyrophosphate, an enzymatic product of IP6K, was correlated with phosphate changes. Chronic IP6K inhibition alleviated hyperphosphataemia, increased kidney ATP, and improved kidney functions in chronic kidney disease rats. Our results demonstrate that the enzymatic activity of IP6K regulates circulating phosphate and intracellular ATP and suggest that IP6K inhibition is a potential novel treatment strategy against hyperphosphataemia. Inositol hexakisphosphate kinase (IP6K) is involved in diverse cellular signalling pathways, but the physiological roles of IP6K in vivo remain unknown in mammals. Here, the authors show that the enzymatic activity of IP6K is essential for phosphate regulation in vivo.
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Affiliation(s)
| | - Shin-Ichi Abe
- Research Division, SCOHIA PHARMA Inc, Kanagawa, Japan
| | | | | | | | - Ryoma Hara
- Research Division, SCOHIA PHARMA Inc, Kanagawa, Japan
| | - Shizuo Kasai
- Research Division, SCOHIA PHARMA Inc, Kanagawa, Japan
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18
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Liao G, Ye W, Heitmann T, Ernst G, DePasquale M, Xu L, Wormald M, Hu X, Ferrer M, Harmel RK, Fiedler D, Barrow J, Wei H. Identification of Small-Molecule Inhibitors of Human Inositol Hexakisphosphate Kinases by High-Throughput Screening. ACS Pharmacol Transl Sci 2021; 4:780-789. [PMID: 33860201 DOI: 10.1021/acsptsci.0c00218] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Indexed: 01/15/2023]
Abstract
Inositol hexakisphosphate kinases (IP6Ks) catalyze pyrophosphorylation of inositol hexakisphosphate (IP6) into inositol 5-diphospho-1,2,3,4,6-pentakisphosphate (IP7), which is involved in numerous areas of cell physiology including glucose homeostasis, blood coagulation, and neurological development. Inhibition of IP6Ks may be effective for the treatment of Type II diabetes, obesity, metabolic complications, thrombosis, and psychiatric disorders. We performed a high-throughput screen (HTS) of 158 410 compounds for IP6K1 inhibitors using a previously developed ADP-Glo Max assay. Of these, 1206 compounds were found to inhibit IP6K1 kinase activity by more than 25%, representing a 0.8% hit rate. Structural clustering analysis of HTS-active compounds, which were confirmed in the dose-response testing using the same kinase assay, revealed diverse clusters that were feasible for future structure-activity relationship (SAR) optimization to potent IP6K inhibitors. Medicinal chemistry SAR efforts in three chemical series identified potent IP6K1 inhibitors which were further validated in an orthogonal LC-MS IP7 analysis. The effects of IP6K1 inhibitors on cellular IP7 levels were further confirmed and were found to correlate with cellular IP6K1 binding measured by a high-throughput cellular thermal shift assay (CETSA).
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Affiliation(s)
- Gangling Liao
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Wenjuan Ye
- National Center for Advancing Translational Sciences, Rockville 20850, Maryland, United States
| | - Tyler Heitmann
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Glen Ernst
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Michael DePasquale
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Laiyi Xu
- Department of Chemistry, McGill University, Montreal, Quebec H3A 0G4, Canada
| | - Michael Wormald
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Xin Hu
- National Center for Advancing Translational Sciences, Rockville 20850, Maryland, United States
| | - Marc Ferrer
- National Center for Advancing Translational Sciences, Rockville 20850, Maryland, United States
| | - Robert K Harmel
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Dorothea Fiedler
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - James Barrow
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
| | - Huijun Wei
- Lieber Institute for Brain Development, Baltimore, Maryland 21205, United States
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19
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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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20
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Lee S, Beon J, Kim MG, Kim S. Inositol polyphosphate multikinase in adipocytes is dispensable for regulating energy metabolism and whole body metabolic homeostasis. Am J Physiol Endocrinol Metab 2020; 319:E401-E409. [PMID: 32634320 DOI: 10.1152/ajpendo.00030.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Adipose tissue plays a central role in regulating whole body energy and glucose homeostasis at both organ and systemic levels. Inositol polyphosphates, such as 5-diphosphoinositol pentakisphosphate, reportedly control adipocyte functions and energy expenditure. However, the physiological roles of the inositol polyphosphate (IP) pathway in the adipose tissue are not yet fully defined. The aim of the present study was to test the hypothesis that inositol polyphosphate multikinase (IPMK), a key enzyme in the IP metabolism, plays a critical role in adipose tissue biology and obesity. We generated adipocyte-specific IPMK knockout (Ipmk AKO) mice and evaluated metabolic phenotypes by measuring fat accumulation, glucose homeostasis, and insulin sensitivity in adult mice fed either a regular-chow diet or high-fat diet (HFD). Despite substantial reduction of IPMK, Ipmk AKO mice exhibited normal glucose tolerance and insulin sensitivity and did not show changes in fat accumulation in response to HFD-feeding. In addition, loss of IPMK had no major impact on thermogenic processes in response to cold exposure. Collectively, these findings suggest that adipocyte IPMK is dispensable for normal adipose tissue and its physiological functions in whole body metabolism, suggesting the complex roles that inositol polyphosphate metabolism has in the regulation of adipose tissue.
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Affiliation(s)
- Seulgi Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Jiyoon Beon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Min-Gyu Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
- KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Korea
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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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Yu D, Wang Y, Yu C, Song M, Zhou Q, Liu S. High-throughput serum metabolomics analysis of gouty arthritis rat treated by total saponins of Rhizoma Dioscoreae Makino by UPLC-Q/TOF-MS. Biomed Chromatogr 2020; 34:e4867. [PMID: 32330320 DOI: 10.1002/bmc.4867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 04/04/2020] [Accepted: 04/20/2020] [Indexed: 12/27/2022]
Abstract
Rhizoma Dioscoreae Makino (RDM) is effective in treating gouty arthritis (GA) and hyperuricacidemia, especially in promoting uric acid excretion and reducing the inflammatory reaction. Bioactive constituents in RDM are mainly steroidal saponins such as dioscin, trillin, protodioscin and protogracillin. However, the mechanism of its anti-GA action is still unclear, owing to the complex pathological and physiological characteristics of GA, and integration of RDM with multiple components, multiple targets and multiple pathways. Herein, a GA rat model was induced with monosodium urate (MSU), and RDM reduced inflammation of rat synovium tissue. Through metabolomics analysis, 35 potential biomarkers with significant changes involved in the pathogenesis of GA induced by MSU were identified, and perturbations were restored after RDM treatment. The most correlated pathways involved in d-galactose, d-mannose, d-glucose, myoinositol, Phosphatidylcholine (PC) (16:0/16:0), LysoPC (15:0), phosphatidic acid (PA) [18:1(9Z)/18:1(11Z)] and glutathione induced by MSU were galactose metabolism, inositol phosphate metabolism, glycerophospholipid metabolism and glutathione metabolism, and the derivations of all those biomarkers could be regulated by RDM treatment. RDM has a therapeutic effect on GA by intervening in changes in endogenous metabolisms and the related metabolic pathways.
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Affiliation(s)
- Donghua Yu
- Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Yu Wang
- Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Chunmiao Yu
- College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Mingyang Song
- Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Qi Zhou
- Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Shumin Liu
- Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin, China
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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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Barclay RD, Beals JW, Drnevich J, Imai BS, Yau PM, Ulanov AV, Tillin NA, Villegas-Montes M, Paluska SA, Watt PW, De Lisio M, Burd NA, Mackenzie RW. Ingestion of lean meat elevates muscle inositol hexakisphosphate kinase 1 protein content independent of a distinct post-prandial circulating proteome in young adults with obesity. Metabolism 2020; 102:153996. [PMID: 31678069 PMCID: PMC7268923 DOI: 10.1016/j.metabol.2019.153996] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/25/2019] [Accepted: 10/06/2019] [Indexed: 01/05/2023]
Abstract
BACKGROUND We have recently shown that a novel signalling kinase, inositol hexakisphosphate kinase 1 (IP6K1), is implicated in whole-body insulin resistance via its inhibitory action on Akt. Insulin and insulin like growth factor 1 (IGF-1) share many intracellular processes with both known to play a key role in glucose and protein metabolism in skeletal muscle. AIMS We aimed to compare IGF/IP6K1/Akt signalling and the plasma proteomic signature in individuals with a range of BMIs after ingestion of lean meat. METHODS Ten lean [Body mass index (BMI) (in kg/m2): 22.7 ± 0.4; Homeostatic model assessment of insulin resistance (HOMAIR): 1.36 ± 0.17], 10 overweight (BMI: 27.1 ± 0.5; HOMAIR: 1.25 ± 0.11), and 10 obese (BMI: 35.9 ± 1.3; HOMAIR: 5.82 ± 0.81) adults received primed continuous L-[ring-13C6]phenylalanine infusions. Blood and muscle biopsy samples were collected at 0 min (post-absorptive), 120 min and 300 min relative to the ingestion of 170 g pork loin (36 g protein and 5 g fat) to examine skeletal muscle protein signalling, plasma proteomic signatures, and whole-body phenylalanine disappearance rates (Rd). RESULTS Phenylalanine Rd was not different in obese compared to lean individuals at all time points and was not responsive to a pork ingestion (basal, P = 0.056; 120 & 300 min, P > 0.05). IP6K1 was elevated in obese individuals at 120 min post-prandial vs basal (P < 0.05). There were no acute differences plasma proteomic profiles between groups in the post-prandial state (P > 0.05). CONCLUSIONS These data demonstrate, for the first time that muscle IP6K1 protein content is elevated after lean meat ingestion in obese adults, suggesting that IP6K1 may be contributing to the dysregulation of nutrient uptake in skeletal muscle. In addition, proteomic analysis showed no differences in proteomic signatures between obese, overweight or lean individuals.
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Affiliation(s)
- Richie D Barclay
- Department of Life Sciences, University of Roehampton, London, UK
| | - Joseph W Beals
- Division of Nutritional Sciences, University of Illinois, Urbana, IL, United States
| | - Jenny Drnevich
- High-Performance Biological Computing, Roy J. Carver Biotechnology Center, University of Illinois, Urbana, IL, United States
| | - Brian S Imai
- Protein Sciences Facility, Roy J. Carver Biotechnology Center, University of Illinois, Urbana, IL, United States
| | - Peter M Yau
- Metabolomics Facility, Roy J. Carver Biotechnology Center, University of Illinois, Urbana, IL, United States
| | - Alexander V Ulanov
- Department of Kinesiology and Community Health, University of Illinois, Urbana, IL, United States
| | - Neale A Tillin
- Department of Life Sciences, University of Roehampton, London, UK
| | | | - Scott A Paluska
- Department of Family Medicine, University of Illinois, Urbana, IL, United States
| | - Peter W Watt
- University of Brighton, Welkin Laboratories, Eastbourne, UK
| | - Michael De Lisio
- School of Human Kinetics, Brain and Mind Institute, Center on Neuromuscular Disease, Regenerative Medicine Program, University of Ottawa, Ottawa, ON, Canada
| | - Nicholas A Burd
- Division of Nutritional Sciences, University of Illinois, Urbana, IL, United States; Department of Kinesiology and Community Health, University of Illinois, Urbana, IL, United States
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25
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Verma V, Prakash O, Malik S, Rani K. Phytochemical screening and bioactive potential of pod seed extracts of Leucaena leucocephala linn. Pharmacognosy Res 2020. [DOI: 10.4103/pr.pr_49_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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26
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Abstract
The multitudinous inositol phosphate family elicits a wide range of molecular effects that regulate countless biological responses. In this review, I provide a methodological viewpoint of the manner in which key advances in the field of inositol phosphate research were made. I also note some of the considerable challenges that still lie ahead.
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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, NC, USA.
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27
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Barclay RD, Burd NA, Tyler C, Tillin NA, Mackenzie RW. The Role of the IGF-1 Signaling Cascade in Muscle Protein Synthesis and Anabolic Resistance in Aging Skeletal Muscle. Front Nutr 2019; 6:146. [PMID: 31552262 PMCID: PMC6746962 DOI: 10.3389/fnut.2019.00146] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 08/23/2019] [Indexed: 12/14/2022] Open
Abstract
Sarcopenia is defined as the combined loss of skeletal muscle strength, function, and/or mass with aging. This degenerative loss of muscle mass is associated with poor quality of life and early mortality humans. The loss of muscle mass occurs due to acute changes in daily muscle net protein balance (NPB). It is generally believed a poor NPB occurs due to reduced muscle protein synthetic responses to exercise, dietary amino acid availability, or an insensitivity of insulin to suppress breakdown. Hence, aging muscles appear to be resistant to the anabolic action of exercise and protein (amino acids or hormonal) when compared to their younger counterparts. The mechanisms that underpin anabolic resistance to anabolic stimuli (protein and resistance exercise) are multifactorial and may be partly driven by poor lifestyle choices (increased sedentary time and reduced dietary protein intake) as well as an inherent dysregulated mechanism in old muscles irrespective of the environmental stimuli. The insulin like growth factor 1 (IGF-1), Akt /Protein Kinase B and mechanistic target of rapamycin (mTOR) pathway is the primary driver between mechanical contraction and protein synthesis and may be a site of dysregulation between old and younger people. Therefore, our review aims to describe and summarize the differences seen in older muscle in this pathway in response to resistance exercise (RE) and describe approaches that researchers have sought out to maximize the response in muscle. Furthermore, this review will present the hypothesis that inositol hexakisphosphate kinase 1 (IP6K1) may be implicated in IGF-1 signaling and thus sarcopenia, based on recent evidence that IGF-1 and insulin share some intracellular bound signaling events and that IP6K1 has been implicated in skeletal muscle insulin resistance.
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Affiliation(s)
- Richie D Barclay
- Department of Life Sciences, University of Roehampton, London, United Kingdom
| | - Nicholas A Burd
- Division of Nutritional Sciences, Department of Kinesiology and Community Health, University of Illinois, Urbana, IL, United States
| | - Christopher Tyler
- Department of Life Sciences, University of Roehampton, London, United Kingdom
| | - Neale A Tillin
- Department of Life Sciences, University of Roehampton, London, United Kingdom
| | - Richard W Mackenzie
- Department of Life Sciences, University of Roehampton, London, United Kingdom
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Wormald MM, Ernst G, Wei H, Barrow JC. Synthesis and characterization of novel isoform-selective IP6K1 inhibitors. Bioorg Med Chem Lett 2019; 29:126628. [PMID: 31445853 DOI: 10.1016/j.bmcl.2019.126628] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/15/2019] [Accepted: 08/17/2019] [Indexed: 11/25/2022]
Abstract
Inositol hexakisphosphate kinases (IP6Ks) have been increasingly studied as therapeutically interesting enzymes. IP6K isoform specific knock-outs have been used to successfully explore inositol pyrophosphate physiology and related pathologies. A pan-IP6K inhibitor, N2-(m-trifluorobenzyl)-N6-(p-nitrobenzyl) purine (TNP), has been used to confirm phenotypes observed in genetic knock-out experiments; however, it suffers by having modest potency and poor solubility making it difficult to handle for in vitro applications in the absence of DMSO. Moreover, TNP's pan-IP6K inhibitory profile does not inform which IP6K isoform is responsible for which phenotypes. In this report we describe a series of purine-based isoform specific IP6K1 inhibitors. The lead compound was identified after multiple rounds of SAR and has been found to selectively inhibit IP6K1 over IP6K2 or IP6K3 using biochemical and biophysical approaches. It also boasts increased solubility and IP6K1 potency over TNP. These new compounds are useful tools for additional assay development and exploration of IP6K1 specific biology.
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Affiliation(s)
- Michael M Wormald
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - Glen Ernst
- Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - Huijun Wei
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA; Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA
| | - James C Barrow
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA; Lieber Institute for Brain Development, 855 North Wolfe Street, Baltimore, MD 21205, USA.
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29
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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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Gu C, Stashko MA, Puhl-Rubio AC, Chakraborty M, Chakraborty A, Frye SV, Pearce KH, Wang X, Shears SB, Wang H. Inhibition of Inositol Polyphosphate Kinases by Quercetin and Related Flavonoids: A Structure-Activity Analysis. J Med Chem 2019; 62:1443-1454. [PMID: 30624931 DOI: 10.1021/acs.jmedchem.8b01593] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Dietary flavonoids inhibit certain protein kinases and phospholipid kinases by competing for their ATP-binding sites. These nucleotide pockets have structural elements that are well-conserved in two human small-molecule kinases, inositol hexakisphosphate kinase (IP6K) and inositol polyphosphate multikinase (IPMK), which synthesize multifunctional inositol phosphate cell signals. Herein, we demonstrate that both kinases are inhibited by quercetin and 16 related flavonoids; IP6K is the preferred target. Relative inhibitory activities were rationalized by X-ray analysis of kinase/flavonoid crystal structures; this detailed structure-activity analysis revealed hydrophobic and polar ligand/protein interactions, the degree of flexibility of key amino acid side chains, and the importance of water molecules. The seven most potent IP6K inhibitors were incubated with intact HCT116 cells at concentrations of 2.5 μM; diosmetin was the most selective and effective IP6K inhibitor (>70% reduction in activity). Our data can instruct on pharmacophore properties to assist the future development of inositol phosphate kinase inhibitors. Finally, we propose that dietary flavonoids may inhibit IP6K activity in cells that line the gastrointestinal tract.
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Affiliation(s)
- Chunfang Gu
- Inositol Signaling Group, Signal Transduction Laboratory , National Institute of Environmental Health Sciences , Research Triangle Park , North Carolina 27709 , United States
| | - Michael A Stashko
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Ana C Puhl-Rubio
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Molee Chakraborty
- Department of Pharmacology and Physiology , Saint Louis University School of Medicine , M370, Schwitalla Hall, 1402 South Grand Boulevard , Saint Louis , Missouri 63104 , United States
| | - Anutosh Chakraborty
- Department of Pharmacology and Physiology , Saint Louis University School of Medicine , M370, Schwitalla Hall, 1402 South Grand Boulevard , Saint Louis , Missouri 63104 , United States
| | - Stephen V Frye
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Kenneth H Pearce
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Xiaodong Wang
- Center for Integrative Chemical Biology and Drug Discovery, Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Stephen B Shears
- Inositol Signaling Group, Signal Transduction Laboratory , National Institute of Environmental Health Sciences , Research Triangle Park , North Carolina 27709 , United States
| | - Huanchen Wang
- Inositol Signaling Group, Signal Transduction Laboratory , National Institute of Environmental Health Sciences , Research Triangle Park , North Carolina 27709 , United States
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31
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Shears SB, Wang H. Inositol phosphate kinases: Expanding the biological significance of the universal core of the protein kinase fold. Adv Biol Regul 2019; 71:118-127. [PMID: 30392847 PMCID: PMC9364425 DOI: 10.1016/j.jbior.2018.10.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/23/2018] [Accepted: 10/26/2018] [Indexed: 05/06/2023]
Abstract
The protein kinase family is characterized by substantial conservation of architectural elements that are required for both ATP binding and phosphotransferase activity. Many of these structural features have also been identified in homologous enzymes that phosphorylate a variety of alternative, non-protein substrates. A comparative structural analysis of these different kinase sub-classes is a portal to a greater understanding of reaction mechanisms, enzyme regulation, inhibitor-development strategies, and superfamily-level evolutionary relationships. To serve such advances, we review structural elements of the protein kinase fold that are conserved in the subfamily of inositol phosphate kinases (InsPKs) that share a PxxxDxKxG catalytic signature: inositol 1,4,5-trisphosphate kinase (IP3K), inositol hexakisphosphate kinase (IP6K), and inositol polyphosphate multikinase (IPMK). We describe conservation of the fundamental two-lobe kinase architecture: an N-lobe constructed upon an anti-parallel β-strand scaffold, which is coupled to a largely helical C-lobe by a single, adenine-binding hinge. This equivalency also includes a G-loop that embraces the β/γ-phosphates of ATP, a transition-state stabilizing residue (Lys/His), and a Mg-positioning aspartate residue within a catalytic triad. Furthermore, we expand this list of conserved structural features to include some not previously identified in InsPKs: a 'gatekeeper' residue in the N-lobe, and an 'αF'-like helix in the C-lobe that anchors two structurally-stabilizing, hydrophobic spines, formed from non-consecutive residues that span the two lobes. We describe how this wide-ranging structural homology can be exploited to develop lead inhibitors of IP6K and IPMK, by using strategies similar to those that have generated ATP-competing inhibitors of protein-kinases. We provide several examples to illustrate how such an approach could benefit human health.
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Affiliation(s)
- Stephen B Shears
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
| | - Huanchen Wang
- Inositol Signaling Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
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32
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Puhl-Rubio AC, Stashko MA, Wang H, Hardy PB, Tyagi V, Li B, Wang X, Kireev D, Jessen HJ, Frye SV, Shears SB, Pearce KH. Use of Protein Kinase-Focused Compound Libraries for the Discovery of New Inositol Phosphate Kinase Inhibitors. SLAS DISCOVERY 2018; 23:982-988. [PMID: 29842835 DOI: 10.1177/2472555218775323] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Inositol hexakisphosphate kinases (IP6Ks) regulate a myriad of cellular processes, not only through their catalytic activity (which synthesizes InsP7, a multifunctional inositol pyrophosphate signaling molecule) but also through protein-protein interactions. To further study the enzymatic function and distinguish between these different mechanisms, specific inhibitors that target IP6K catalytic activity are required. Only one IP6K inhibitor is commonly used: N2-( m-(trifluoromethyl)benzyl) N6-( p-nitrobenzyl)purine (TNP). TNP is, however, compromised by weak potency, inability to distinguish between IP6K isoenzymes, off-target activities, and poor pharmacokinetic properties. Herein, we describe a new inhibitor discovery strategy, based on the high degree of structural conservation of the nucleotide-binding sites of IP6Ks and protein kinases; we screened for novel IP6K2 inhibitors using a focused set of compounds with features known, or computationally predicted, to target nucleotide binding by protein kinases. We developed a time-resolved fluorescence resonance energy transfer (TR-FRET) assay of adenosine diphosphate (ADP) formation from adenosine triphosphate (ATP). Novel hit compounds for IP6K2 were identified and validated with dose-response curves and an orthogonal assay. None of these inhibitors affected another inositol pyrophosphate kinase, PPIP5K. Our screening strategy offers multiple IP6K2 inhibitors for future development and optimization. This approach will be applicable to inhibitor discovery campaigns for other inositol phosphate kinases.
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Affiliation(s)
- Ana C Puhl-Rubio
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Michael A Stashko
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Huanchen Wang
- 2 Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - P Brian Hardy
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Vikas Tyagi
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA.,4 School of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology (TIET), Patiala, Punjab, India
| | - Bing Li
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Xiaodong Wang
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Dmitri Kireev
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Henning J Jessen
- 3 Institute of Organic Chemistry, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Stephen V Frye
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Stephen B Shears
- 2 Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Kenneth H Pearce
- 1 Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
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Fu C, Rojas T, Chin AC, Cheng W, Bernstein IA, Albacarys LK, Wright WW, Snyder SH. Multiple aspects of male germ cell development and interactions with Sertoli cells require inositol hexakisphosphate kinase-1. Sci Rep 2018; 8:7039. [PMID: 29728588 PMCID: PMC5935691 DOI: 10.1038/s41598-018-25468-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 04/19/2018] [Indexed: 12/30/2022] Open
Abstract
Inositol hexakisphosphate kinase-1 (IP6K1) is required for male fertility, but the underlying mechanisms have been elusive. Here, we report that IP6K1 is required for multiple aspects of male germ cell development. This development requires selective interactions between germ cells and Sertoli cells, namely apical ectoplasmic specialization. Spermiation (sperm release) requires tubulobulbar complexes. We found that the apical ectoplasmic specialization and tubulobulbar complexes were poorly formed or disrupted in IP6K1 KOs. Deletion of IP6K1 elicited several aberrations, including: 1, sloughing off of round germ cells; 2, disorientation and malformation of elongating/elongated spermatids; 3, degeneration of acrosomes; 4, defects in germ-Sertoli cell interactions and 5, failure of spermiation. Eventually the sperm cells were not released but phagocytosed by Sertoli cells leading to an absence of sperm in the epididymis.
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Affiliation(s)
- Chenglai Fu
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, 300070, China. .,The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| | - Tomas Rojas
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Alfred C Chin
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Weiwei Cheng
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Isaac A Bernstein
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Lauren K Albacarys
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - William W Wright
- Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Solomon H Snyder
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA. .,Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA. .,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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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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Naufahu J, Elliott B, Markiv A, Dunning-Foreman P, McGrady M, Howard D, Watt P, Mackenzie RWA. High-Intensity Exercise Decreases IP6K1 Muscle Content and Improves Insulin Sensitivity (SI2*) in Glucose-Intolerant Individuals. J Clin Endocrinol Metab 2018; 103:1479-1490. [PMID: 29300979 DOI: 10.1210/jc.2017-02019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/20/2017] [Indexed: 12/13/2022]
Abstract
CONTEXT Insulin resistance (IR) in skeletal muscle contributes to whole body hyperglycemia and the secondary complications associated with type 2 diabetes. Inositol hexakisphosphate kinase-1 (IP6K1) may inhibit insulin-stimulated glucose transport in this tissue type. OBJECTIVE Muscle and plasma IP6K1 were correlated with two-compartment models of glucose control in insulin-resistant hyperinsulinemic individuals. Muscle IP6K1 was also compared after two different exercise trials. DESIGN Nine prediabetic [hemoglobin A1c; 6.1% (0.2%)] patients were recruited to take part in a resting control, a continuous exercise (90% of lactate threshold), and a high-intensity exercise trial (6 30-second sprints). Muscle biopsies were drawn before and after each 60-minute trial. A labeled ([6,62H2]glucose) intravenous glucose tolerance test was performed immediately after the second muscle sample. RESULTS Fasting muscle IP6K1 content did not correlate with insulin sensitivity (SI2*) (P = 0.961). High-intensity exercise reduced IP6K1 muscle protein and messenger RNA expression (P = 0.001). There was no effect on protein IP6K1 content after continuous exercise. Akt308 phosphorylation of was significantly greater after high-intensity exercise. Intermittent exercise reduced hepatic glucose production after the same trial. The same intervention also increased SI2*, and this effect was significantly greater compared with the effect of continuous exercise improvements. Our in vitro experiment demonstrated that the chemical inhibition of IP6K1 increased insulin signaling in C2C12 myotubes. CONCLUSIONS The in vivo and in vitro approaches used in the current study suggest that a decrease in muscle IP6K1 may be linked to whole body increases in SI2*. In addition, high-intensity exercise reduces hepatic glucose production in insulin-resistant individuals.
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Affiliation(s)
- Jane Naufahu
- Faculty of Science and Technology, Department of Life Sciences, University of Westminster, London, United Kingdom
| | - Bradley Elliott
- Faculty of Science and Technology, Department of Life Sciences, University of Westminster, London, United Kingdom
| | - Anatoliy Markiv
- Biosciences Education, King's College London, London, United Kingdom
| | - Petra Dunning-Foreman
- Faculty of Science and Technology, Department of Life Sciences, University of Westminster, London, United Kingdom
| | - Maggie McGrady
- Faculty of Science and Technology, Department of Life Sciences, University of Westminster, London, United Kingdom
| | - David Howard
- Department of Oncology, Charing Cross Hospital, Imperial NHS Trust Hospitals, London, United Kingdom
| | - Peter Watt
- Centre for Sport and Exercise Science and Medicine (SESAME), University of Brighton, Eastbourne, United Kingdom
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Rajasekaran SS, Kim J, Gaboardi GC, Gromada J, Shears SB, Dos Santos KT, Nolasco EL, Ferreira SDS, Illies C, Köhler M, Gu C, Ryu SH, Martins JO, Darè E, Barker CJ, Berggren PO. Inositol hexakisphosphate kinase 1 is a metabolic sensor in pancreatic β-cells. Cell Signal 2018. [PMID: 29522819 PMCID: PMC5899964 DOI: 10.1016/j.cellsig.2018.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Diphosphoinositol pentakisphosphate (IP7) is critical for the exocytotic capacity of the pancreatic β-cell, but its regulation by the primary instigator of β-cell exocytosis, glucose, is unknown. The high Km for ATP of the IP7-generating enzymes, the inositol hexakisphosphate kinases (IP6K1 and 2) suggests that these enzymes might serve as metabolic sensors in insulin secreting β-cells and act as translators of disrupted metabolism in diabetes. We investigated this hypothesis and now show that glucose stimulation, which increases the ATP/ADP ratio, leads to an early rise in IP7 concentration in β-cells. RNAi mediated knock down of the IP6K1 isoform inhibits both glucose-mediated increase in IP7 and first phase insulin secretion, demonstrating that IP6K1 integrates glucose metabolism and insulin exocytosis. In diabetic mouse islets the deranged ATP/ADP levels under both basal and glucose-stimulated conditions are mirrored in both disrupted IP7 generation and insulin release. Thus the unique metabolic sensing properties of IP6K1 guarantees appropriate concentrations of IP7 and thereby both correct basal insulin secretion and intact first phase insulin release. In addition, our data suggest that a specific cell signaling defect, namely, inappropriate IP7 generation may be an essential convergence point integrating multiple metabolic defects into the commonly observed phenotype in diabetes. Glucose increases IP7 levels transiently through IP6K1 in pancreatic β-cells. IP6K1 decodes glucose-driven increases in ATP/ADP ratio into 1st phase insulin release. IP7 production and insulin release mirror perturbed metabolism in diabetic islets. IP6K1 acts as a β-cell metabolic sensor under normal and pathological conditions.
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Affiliation(s)
- Subu Surendran Rajasekaran
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Jaeyoon Kim
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Gian-Carlo Gaboardi
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | | | - Stephen B Shears
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239,111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Karen Tiago Dos Santos
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Eduardo Lima Nolasco
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Sabrina de Souza Ferreira
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Christopher Illies
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Martin Köhler
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Chunfang Gu
- Signal Transduction Laboratory/Inositol Signaling Group, NIEHS, Building 101, Room F239,111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Joilson O Martins
- Laboratory of Immunoendocrinology, Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elisabetta Darè
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
| | - Christopher J Barker
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
| | - Per-Olof Berggren
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
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Wormald M, Liao G, Kimos M, Barrow J, Wei H. Development of a homogenous high-throughput assay for inositol hexakisphosphate kinase 1 activity. PLoS One 2017; 12:e0188852. [PMID: 29186181 PMCID: PMC5706701 DOI: 10.1371/journal.pone.0188852] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 11/14/2017] [Indexed: 11/18/2022] Open
Abstract
Inositol pyrophosphates have been implicated in a wide range of cellular processes. Inositol hexakisphosphate kinase 1 catalyzes the pyrophosphorylation of inositol hexakisphosphate into inositol 5-diphospho-1,2,3,4,6-pentakisphosphate which is important in numerous areas of cell physiology such as DNA repair and glucose homeostasis. Furthermore, inositol 5-diphospho-1,2,3,4,6-pentakisphosphate is implicated in the pathology of diabetes and other human diseases. As such there is a demonstrated need in the field for a robust chemical probe to better understand the role of inositol hexakisphosphate kinase 1 and inositol pyrophosphate in physiology and disease. To aid in this effort we developed a homogenous coupled bioluminescence assay for measuring inositol hexakisphosphate kinase 1 activity in a 384-well format (Z’ = 0.62±0.05). Using this assay we were able to confirm the activity of a known inositol hexakisphosphate kinase 1 inhibitor N2-(m-trifluorobenzyl), N6-(p-nitrobenzyl)purine. We also screened the Sigma library of pharmacologically active compounds at 10μM concentration and found 24 hits. Two of the most potent compounds were found to have an IC50 less than 5μM. The use of this high-throughput assay will accelerate the field towards the discovery of a potent inositol hexakisphosphate kinase 1 inhibitor.
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Affiliation(s)
- Michael Wormald
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, Maryland, United States of America
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, Maryland, United States of America
| | - Gangling Liao
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, Maryland, United States of America
| | - Martha Kimos
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, Maryland, United States of America
| | - James Barrow
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, Maryland, United States of America
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, Maryland, United States of America
| | - Huijun Wei
- Drug Discovery Division, Lieber Institute for Brain Development, Baltimore, Maryland, United States of America
- * E-mail:
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Malla AB, Bhandari R. IP6K1 is essential for chromatoid body formation and temporal regulation of Tnp2 and Prm2 expression in mouse spermatids. J Cell Sci 2017; 130:2854-2866. [PMID: 28743739 DOI: 10.1242/jcs.204966] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 07/13/2017] [Indexed: 12/25/2022] Open
Abstract
Inositol hexakisphosphate kinases (IP6Ks) are enzymes that synthesise the inositol pyrophosphate 5-diphosphoinositol pentakisphosphate (5-IP7), which is known to regulate several physiological processes. Deletion of IP6K1, but not other IP6K isoforms, causes sterility in male mice. Here, we present a detailed investigation of the specific function of IP6K1 in spermatogenesis. Within the mouse testis, IP6K1 is expressed at high levels in late stage pachytene spermatocytes and in round spermatids. We found IP6K1 to be a novel component of the chromatoid body, a cytoplasmic granule found in round spermatids that is composed of RNA and RNA-binding proteins, and noted that this structure is absent in Ip6k1-/- round spermatids. Furthermore, juvenile spermatids from Ip6k1-/- mice display premature expression of the transition protein TNP2 and the protamine PRM2 due to translational derepression. The aberrant localisation of these key sperm-specific chromatin components, together with the persistence of somatic histones, results in abnormal spermatid elongation, failure to complete spermatid differentiation and azoospermia in these mice. Our study thus identifies IP6K1 as an indispensable factor in the temporal regulation of male germ cell differentiation.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Aushaq Bashir Malla
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana 500001, India.,Graduate Studies, Manipal University, Manipal, Karnataka 576104, India
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana 500001, India
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Boregowda SV, Ghoshal S, Booker CN, Krishnappa V, Chakraborty A, Phinney DG. IP6K1 Reduces Mesenchymal Stem/Stromal Cell Fitness and Potentiates High Fat Diet-Induced Skeletal Involution. Stem Cells 2017; 35:1973-1983. [PMID: 28577302 PMCID: PMC5533188 DOI: 10.1002/stem.2645] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/27/2017] [Accepted: 05/12/2017] [Indexed: 12/12/2022]
Abstract
Mesenchymal stem/stromal cells (MSCs) are the predominant source of bone and adipose tissue in adult bone marrow and play a critical role in skeletal homeostasis. Age‐induced changes in bone marrow favor adipogenesis over osteogenesis leading to skeletal involution and increased marrow adiposity so pathways that prevent MSC aging are potential therapeutic targets for treating age‐related bone diseases. Here, we show that inositol hexakisphosphate kinase 1 (Ip6k1) deletion in mice increases MSC yields from marrow and enhances cell growth and survival ex vivo. In response to the appropriate stimuli, Ip6k1−/− versus Ip6k1+/+ MSCs also exhibit enhanced osteogenesis and hematopoiesis‐supporting activity and reduced adipogenic differentiation. Mechanistic‐based studies revealed that Ip6k1−/− MSCs express higher MDM2 and lower p53 protein levels resulting in lower intrinsic mitochondrial reactive oxygen species (ROS) levels as compared to Ip6k1+/+ MSCs, but both populations upregulate mitochondrial ROS to similar extents in response to oxygen‐induced stress. Finally, we show that mice fed a high fat diet exhibit reduced trabecular bone volume, and that pharmacological inhibition of IP6K1 using a pan‐IP6K inhibitor largely reversed this phenotype while increasing MSC yields from bone marrow. Together, these findings reveal an important role for IP6K1 in regulating MSC fitness and differentiation fate. Unlike therapeutic interventions that target peroxisome proliferator‐activated receptor gamma and leptin receptor activity, which yield detrimental side effects including increased fracture risk and altered feeding behavior, respectively, inhibition of IP6K1 maintains insulin sensitivity and prevents obesity while preserving bone integrity. Therefore, IP6K1 inhibitors may represent more effective insulin sensitizers due to their bone sparing properties. Stem Cells2017;35:1973–1983
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Affiliation(s)
- Siddaraju V Boregowda
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
| | - Sarbani Ghoshal
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
| | - Cori N Booker
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
| | - Veena Krishnappa
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
| | - Anutosh Chakraborty
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
| | - Donald G Phinney
- Department of Molecular Medicine, The Scripps Research Institute-Scripps Florida, Jupiter, Florida, USA
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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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Neuronal migration is mediated by inositol hexakisphosphate kinase 1 via α-actinin and focal adhesion kinase. Proc Natl Acad Sci U S A 2017; 114:2036-2041. [PMID: 28154132 DOI: 10.1073/pnas.1700165114] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Inositol hexakisphosphate kinase 1 (IP6K1), which generates 5-diphosphoinositol pentakisphosphate (5-IP7), physiologically mediates numerous functions. We report that IP6K1 deletion leads to brain malformation and abnormalities of neuronal migration. IP6K1 physiologically associates with α-actinin and localizes to focal adhesions. IP6K1 deletion disrupts α-actinin's intracellular localization and function. The IP6K1 deleted cells display substantial decreases of stress fiber formation and impaired cell migration and spreading. Regulation of α-actinin by IP6K1 requires its kinase activity. Deletion of IP6K1 abolishes α-actinin tyrosine phosphorylation, which is known to be regulated by focal adhesion kinase (FAK). FAK phosphorylation is substantially decreased in IP6K1 deleted cells. 5-IP7, a product of IP6K1, promotes FAK autophosphorylation. Pharmacologic inhibition of IP6K by TNP [N2-(m-Trifluorobenzyl), N6-(p-nitrobenzyl)purine] recapitulates the phenotype of IP6K1 deletion. These findings establish that IP6K1 physiologically regulates neuronal migration by binding to α-actinin and influencing phosphorylation of both FAK and α-actinin through its product 5-IP7.
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Zhu Q, Ghoshal S, Tyagi R, Chakraborty A. Global IP6K1 deletion enhances temperature modulated energy expenditure which reduces carbohydrate and fat induced weight gain. Mol Metab 2016; 6:73-85. [PMID: 28123939 PMCID: PMC5220553 DOI: 10.1016/j.molmet.2016.11.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/15/2016] [Accepted: 11/23/2016] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVE IP6 kinases (IP6Ks) regulate cell metabolism and survival. Mice with global (IP6K1-KO) or adipocyte-specific (AdKO) deletion of IP6K1 are protected from diet induced obesity (DIO) at ambient (23 °C) temperature. AdKO mice are lean primarily due to increased AMPK mediated thermogenic energy expenditure (EE). Thus, at thermoneutral (30 °C) temperature, high fat diet (HFD)-fed AdKO mice expend energy and gain body weight, similar to control mice. IP6K1 is ubiquitously expressed; thus, it is critical to determine to what extent the lean phenotype of global IP6K1-KO mice depends on environmental temperature. Furthermore, it is not known whether IP6K1 regulates AMPK mediated EE in cells, which do not express UCP1. METHODS Q-NMR, GTT, food intake, EE, QRT-PCR, histology, mitochondrial oxygen consumption rate (OCR), fatty acid metabolism assays, and immunoblot studies were conducted in IP6K1-KO and WT mice or cells. RESULTS Global IP6K1 deletion mediated enhancement in EE is impaired albeit not abolished at 30 °C. As a result, IP6K1-KO mice are protected from DIO, insulin resistance, and fatty liver even at 30 °C. Like AdKO, IP6K1-KO mice display enhanced adipose tissue browning. However, unlike AdKO mice, thermoneutrality only partly abolishes browning in IP6K1-KO mice. Cold (5 °C) exposure enhances carbohydrate expenditure, whereas 23 °C and 30 °C promote fat oxidation in HFD-KO mice. Furthermore, IP6K1 deletion diminishes cellular fat accumulation via activation of the AMPK signaling pathway. CONCLUSIONS Global deletion of IP6K1 ameliorates obesity and insulin resistance irrespective of the environmental temperature conditions, which strengthens its validity as an anti-obesity target.
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Affiliation(s)
- Qingzhang Zhu
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Sarbani Ghoshal
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL, 33458, USA
| | - Richa Tyagi
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Anutosh Chakraborty
- Department of Metabolism and Aging, The Scripps Research Institute, Jupiter, FL, 33458, USA.
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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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