1
|
Di Giorgio E, Cortolezzis Y, Gualandi N, Agostini F, Rapozzi V, Xodo LE. NRF2 interacts with distal enhancer and inhibits nitric oxide synthase 2 expression in KRAS-driven pancreatic cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119606. [PMID: 37852325 DOI: 10.1016/j.bbamcr.2023.119606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 10/07/2023] [Accepted: 10/10/2023] [Indexed: 10/20/2023]
Abstract
Nitric oxide is a pleiotropic free radical produced by three nitric oxide synthases (NOS1-3), of which inducible NOS2 is involved in tumor initiation and progression. In this study, RNA-seq, ChIP-seq and qRT-PCR experiments combined with bioinformatic analyses showed that NRF2 is a repressor of NOS2 gene by maintaining a distal enhancer located 22 kb downstream of TSS in an inactive state. Deletion of NRF2 leads to activation of the enhancer, which exerts a pioneering function before it is fully activated. Specifically, NRF2 controls the expression of NOS2 in response to intracellular oxidative stress and extracellular oxygen pressure. We found that abrogation of NOS2 expression by siRNAs partially reduced the ability of WT Panc-1 cells to form 3D spheroids, but strongly reduced the formation of 3D spheroids by NRF2-depleted Panc-1 cells. Mechanistically, this effect correlates with the finding that NOS2 and nitric oxide stimulate epithelial-to-mesenchymal transition in NRF2-depleted Panc-1 and MIA PaCa-2 cells. We also found that knockdown of NOS2 leads to blockade of 3D matrigel invasion of NRF2-depleted PDAC cells, demonstrating that a short-circuit in the reciprocal regulation of NOS2 and NRF2 attenuates the malignancy of PDAC cells. In summary, we show for the first time that: (i) NRF2 is a suppressor of NOS2 in pancreatic cancer cells; (ii) NRF2 binds to and inactivates an enhancer located 22 kb downstream of TSS of the NOS2 gene; (iii) activation of NOS2 requires suppression of NRF2; (iv) NOS2 is required for NRF2-depleted Panc-1 cells to maintain their malignancy and invasiveness.
Collapse
Affiliation(s)
- Eros Di Giorgio
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy.
| | - Ylenia Cortolezzis
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy
| | - Nicolò Gualandi
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy
| | - Francesca Agostini
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy
| | - Valentina Rapozzi
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy
| | - Luigi E Xodo
- Department of Medicine, Laboratory of Biochemistry, P.le Kolbe 4, 33100 Udine, Italy.
| |
Collapse
|
2
|
Russell TM, Richardson DR. The good Samaritan glutathione-S-transferase P1: An evolving relationship in nitric oxide metabolism mediated by the direct interactions between multiple effector molecules. Redox Biol 2022; 59:102568. [PMID: 36563536 PMCID: PMC9800640 DOI: 10.1016/j.redox.2022.102568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/22/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022] Open
Abstract
Glutathione-S-transferases (GSTs) are phase II detoxification isozymes that conjugate glutathione (GSH) to xenobiotics and also suppress redox stress. It was suggested that GSTs have evolved not to enhance their GSH affinity, but to better interact with and metabolize cytotoxic nitric oxide (NO). The interactions between NO and GSTs involve their ability to bind and store NO as dinitrosyl-dithiol iron complexes (DNICs) within cells. Additionally, the association of GSTP1 with inducible nitric oxide synthase (iNOS) results in its inhibition. The function of NO in vasodilation together with studies associating GSTM1 or GSTT1 null genotypes with preeclampsia, additionally suggests an intriguing connection between NO and GSTs. Furthermore, suppression of c-Jun N-terminal kinase (JNK) activity occurs upon increased levels of GSTP1 or NO that decreases transcription of JNK target genes such as c-Jun and c-Fos, which inhibit apoptosis. This latter effect is mediated by the direct association of GSTs with MAPK proteins. GSTP1 can also inhibit nuclear factor kappa B (NF-κB) signaling through its interactions with IKKβ and Iκα, resulting in decreased iNOS expression and the stimulation of apoptosis. It can be suggested that the inhibitory activity of GSTP1 within the JNK and NF-κB pathways may be involved in crosstalk between survival and apoptosis pathways and modulating NO-mediated ROS generation. These studies highlight an innovative role of GSTs in NO metabolism through their interaction with multiple effector proteins, with GSTP1 functioning as a "good Samaritan" within each pathway to promote favorable cellular conditions and NO levels.
Collapse
Affiliation(s)
- Tiffany M. Russell
- Department of Pathology and Biological Responses, Nagoya University Graduate School of Medicine, Nagoya, 466-8550, Japan
| | - Des R. Richardson
- Centre for Cancer Cell Biology and Drug Discovery, Griffith Institute for Drug Discovery, Griffith University, Nathan, 4111, Australia,Corresponding author. Centre for Cancer Cell Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, Brisbane, 4111, Queensland, Australia.
| |
Collapse
|
3
|
Tauc M, Cougnon M, Carcy R, Melis N, Hauet T, Pellerin L, Blondeau N, Pisani DF. The eukaryotic initiation factor 5A (eIF5A1), the molecule, mechanisms and recent insights into the pathophysiological roles. Cell Biosci 2021; 11:219. [PMID: 34952646 PMCID: PMC8705083 DOI: 10.1186/s13578-021-00733-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/14/2021] [Indexed: 11/29/2022] Open
Abstract
Since the demonstration of its involvement in cell proliferation, the eukaryotic initiation factor 5A (eIF5A) has been studied principally in relation to the development and progression of cancers in which the isoform A2 is mainly expressed. However, an increasing number of studies report that the isoform A1, which is ubiquitously expressed in normal cells, exhibits novel molecular features that reveal its new relationships between cellular functions and organ homeostasis. At a first glance, eIF5A can be regarded, among other things, as a factor implicated in the initiation of translation. Nevertheless, at least three specificities: (1) its extreme conservation between species, including plants, throughout evolution, (2) its very special and unique post-translational modification through the activating-hypusination process, and finally (3) its close relationship with the polyamine pathway, suggest that the role of eIF5A in living beings remains to be uncovered. In fact, and beyond its involvement in facilitating the translation of proteins containing polyproline residues, eIF5A is implicated in various physiological processes including ischemic tolerance, metabolic adaptation, aging, development, and immune cell differentiation. These newly discovered physiological properties open up huge opportunities in the clinic for pathologies such as, for example, the ones in which the oxygen supply is disrupted. In this latter case, organ transplantation, myocardial infarction or stroke are concerned, and the current literature defines eIF5A as a new drug target with a high level of potential benefit for patients with these diseases or injuries. Moreover, the recent use of genomic and transcriptomic association along with metadata studies also revealed the implication of eIF5A in genetic diseases. Thus, this review provides an overview of eIF5A from its molecular mechanism of action to its physiological roles and the clinical possibilities that have been recently reported in the literature.
Collapse
Affiliation(s)
- Michel Tauc
- LP2M, CNRS, Université Côte d'Azur, Nice, France. .,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France. .,Laboratoire de Physiomédecine Moléculaire, UMR7370, Faculté de Médecine, CNRS, Université Côte d'Azur, 28 Avenue de Valombrose, 06107, Nice Cedex, France.
| | - Marc Cougnon
- LP2M, CNRS, Université Côte d'Azur, Nice, France.,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Romain Carcy
- Service de Réanimation Polyvalente et Service de Réanimation des Urgences Vitales, CHU Nice, Hôpital Pasteur 2, Nice, France
| | - Nicolas Melis
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Thierry Hauet
- INSERM, IRTOMIT, CHU de Poitiers, Université de Poitiers, La Milétrie, Poitiers, France
| | - Luc Pellerin
- INSERM, IRTOMIT, CHU de Poitiers, Université de Poitiers, La Milétrie, Poitiers, France
| | - Nicolas Blondeau
- Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France.,IPMC, CNRS, Université Côte d'Azur, Valbonne, France
| | - Didier F Pisani
- LP2M, CNRS, Université Côte d'Azur, Nice, France.,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| |
Collapse
|
4
|
Takatani T, Shirakawa J, Shibue K, Gupta MK, Kim H, Lu S, Hu J, White MF, Kennedy RT, Kulkarni RN. Insulin receptor substrate 1, but not IRS2, plays a dominant role in regulating pancreatic alpha cell function in mice. J Biol Chem 2021; 296:100646. [PMID: 33839150 PMCID: PMC8131928 DOI: 10.1016/j.jbc.2021.100646] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/24/2021] [Accepted: 04/07/2021] [Indexed: 11/29/2022] Open
Abstract
Dysregulated glucagon secretion deteriorates glycemic control in type 1 and type 2 diabetes. Although insulin is known to regulate glucagon secretion via its cognate receptor (insulin receptor, INSR) in pancreatic alpha cells, the role of downstream proteins and signaling pathways underlying insulin's activities are not fully defined. Using in vivo (knockout) and in vitro (knockdown) studies targeting insulin receptor substrate (IRS) proteins, we compared the relative roles of IRS1 and IRS2 in regulating alpha cell function. Alpha cell-specific IRS1-knockout mice exhibited glucose intolerance and inappropriate glucagon suppression during glucose tolerance tests. In contrast, alpha cell-specific IRS2-knockout animals manifested normal glucose tolerance and suppression of glucagon secretion after glucose administration. Alpha cell lines with stable IRS1 knockdown could not repress glucagon mRNA expression and exhibited a reduction in phosphorylation of AKT Ser/Thr kinase (AKT, at Ser-473 and Thr-308). AlphaIRS1KD cells also displayed suppressed global protein translation, including reduced glucagon expression, impaired cytoplasmic Ca2+ response, and mitochondrial dysfunction. This was supported by the identification of novel IRS1-specific downstream target genes, Trpc3 and Cartpt, that are associated with glucagon regulation in alpha cells. These results provide evidence that IRS1, rather than IRS2, is a dominant regulator of pancreatic alpha cell function.
Collapse
Affiliation(s)
- Tomozumi Takatani
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Jun Shirakawa
- Laboratory of Diabetes and Metabolic Disorders, Institute for Molecular and Cellular Regulation (IMCR), Gunma University, Gunma, Japan
| | - Kimitaka Shibue
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Manoj K Gupta
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Cell Therapy Translational Engine (CTTE), Takeda Pharmaceuticals, Cambridge, Massachusetts, USA
| | - Hyunki Kim
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Shusheng Lu
- Departments of Chemistry and Pharmacology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jiang Hu
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Morris F White
- Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Robert T Kennedy
- Departments of Chemistry and Pharmacology, University of Michigan, Ann Arbor, Michigan, USA
| | - Rohit N Kulkarni
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Harvard Stem Cell Institute, Harvard Medical School, Boston, Massachusetts, USA.
| |
Collapse
|
5
|
Wang C, Chen Z, Nie L, Tang M, Feng X, Su D, Zhang H, Xiong Y, Park JM, Chen J. Extracellular signal-regulated kinases associate with and phosphorylate DHPS to promote cell proliferation. Oncogenesis 2020; 9:85. [PMID: 32989218 PMCID: PMC7522278 DOI: 10.1038/s41389-020-00271-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/30/2020] [Accepted: 09/15/2020] [Indexed: 11/09/2022] Open
Abstract
The ERK1/2 pathway is one of the most commonly dysregulated pathways in human cancers and controls many vital cellular processes. Although many ERK1/2 kinase substrates have been identified, the diversity of ERK1/2 mediated processes suggests the existence of additional targets. Here, we identified Deoxyhypusine synthase (DHPS), an essential hypusination enzyme regulating protein translation, as a major and direct-binding protein of ERK1/2. Further experiments showed that ERK1/2 phosphorylate DHPS at Ser-233 site. The Ser-233 phosphorylation of DHPS by ERK1/2 is important for its function in cell proliferation. Moreover, we found that higher DHPS expression correlated with poor prognosis in lung adenocarcinoma and increased resistance to inhibitors of the ERK1/2 pathway. In summary, our results suggest that ERK1/2-mediated DHPS phosphorylation is an important mechanism that underlies protein translation and that DHPS expression is a potent biomarker of response to therapies targeting ERK1/2-pathway.
Collapse
Affiliation(s)
- Chao Wang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Zhen Chen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Litong Nie
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Mengfan Tang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Xu Feng
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Dan Su
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Huimin Zhang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Yun Xiong
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Jeong-Min Park
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Junjie Chen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
| |
Collapse
|
6
|
Levasseur EM, Yamada K, Piñeros AR, Wu W, Syed F, Orr KS, Anderson-Baucum E, Mastracci TL, Maier B, Mosley AL, Liu Y, Bernal-Mizrachi E, Alonso LC, Scott D, Garcia-Ocaña A, Tersey SA, Mirmira RG. Hypusine biosynthesis in β cells links polyamine metabolism to facultative cellular proliferation to maintain glucose homeostasis. Sci Signal 2019; 12:eaax0715. [PMID: 31796630 PMCID: PMC7202401 DOI: 10.1126/scisignal.aax0715] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Deoxyhypusine synthase (DHPS) uses the polyamine spermidine to catalyze the hypusine modification of the mRNA translation factor eIF5A and promotes oncogenesis through poorly defined mechanisms. Because germline deletion of Dhps is embryonically lethal, its role in normal postnatal cellular function in vivo remains unknown. We generated a mouse model that enabled the inducible, postnatal deletion of Dhps specifically in postnatal islet β cells, which function to maintain glucose homeostasis. Removal of Dhps did not have an effect under normal physiologic conditions. However, upon development of insulin resistance, which induces β cell proliferation, Dhps deletion caused alterations in proteins required for mRNA translation and protein secretion, reduced production of the cell cycle molecule cyclin D2, impaired β cell proliferation, and induced overt diabetes. We found that hypusine biosynthesis was downstream of protein kinase C-ζ and was required for c-Myc-induced proliferation. Our studies reveal a requirement for DHPS in β cells to link polyamines to mRNA translation to effect facultative cellular proliferation and glucose homeostasis.
Collapse
Affiliation(s)
- Esther M Levasseur
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Kentaro Yamada
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Annie R Piñeros
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Wenting Wu
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Farooq Syed
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Kara S Orr
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | - Teresa L Mastracci
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA
| | - Bernhard Maier
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Amber L Mosley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | - Laura C Alonso
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Donald Scott
- Diabetes, Obesity, and Metabolism Institute and the Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Adolfo Garcia-Ocaña
- Diabetes, Obesity, and Metabolism Institute and the Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sarah A Tersey
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Raghavendra G Mirmira
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| |
Collapse
|
7
|
Jung YK, Park HR, Cho HJ, Jang JA, Lee EJ, Han MS, Kim GW, Han S. Degrading products of chondroitin sulfate can induce hypertrophy-like changes and MMP-13/ADAMTS5 production in chondrocytes. Sci Rep 2019; 9:15846. [PMID: 31676809 PMCID: PMC6825126 DOI: 10.1038/s41598-019-52358-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 10/14/2019] [Indexed: 12/18/2022] Open
Abstract
Chondroitin sulfate (CS) is the most abundant glycosaminoglycan (GAG) in articular cartilage and the loss of CS-GAG occurs early in OA. As a major component of perichondral matrix interacting directly with chondrocytes, the active turnover of CS can affect to break the homeostasis of chondrocytes. Here we employ CS-based 3-dimensional (3D) hydrogel scaffold system to investigate how the degradation products of CS affect the catabolic phenotype of chondrocytes. The breakdown of CS-based ECM by the chondroitinase ABC (ChABC) resulted in a hypertrophy-like morphologic change in chondrocytes, which was accompanied by catabolic phenotypes, including increased MMP-13 and ADAMTS5 expression, nitric oxide (NO) production and oxidative stress. The inhibition of Toll-like receptor 2 (TLR2) or TLR4 with OxPAPC (TLR2 and TLR4 dual inhibitor) and LPS-RS (TLR4-MD2 inhibitor) ameliorated these catabolic phenotypes of chondrocytes by CS-ECM degradation, suggesting a role of CS breakdown products as damage-associated molecular patterns (DAMPs). As downstream signals of TLRs, MAP kinases, NF-kB, NO and STAT3-related signals were responsible for the catabolic phenotypes of chondrocytes associated with ECM degradation. NO in turn reinforced the activation of MAP kinases as well as NFkB signaling pathway. Thus, these results propose that the breakdown product of CS-GAG can recapitulate the catabolic phenotypes of OA.
Collapse
Affiliation(s)
- Youn-Kwan Jung
- Biomedical Research Institute, Gyeongsang National University Hospital, Jinju, Gyeongsangnam-do, Republic of Korea
| | - Hye-Ri Park
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea
| | - Hyun-Jung Cho
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea
| | - Ji-Ae Jang
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea
| | - Eun-Ju Lee
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea
| | - Min-Su Han
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea
| | - Gun-Woo Kim
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea.,Department of Internal medicine, Daegu Fatima Hospital, Daegu, Republic of Korea
| | - Seungwoo Han
- Laboratory for arthritis and bone biology, Fatima Research Institute, Daegu Fatima hospital, Daegu, Republic of Korea. .,Department of Internal medicine, Kyungpook National University Hospital, Daegu, Republic of Korea.
| |
Collapse
|
8
|
Turpaev KT. Translation Factor eIF5A, Modification with Hypusine and Role in Regulation of Gene Expression. eIF5A as a Target for Pharmacological Interventions. BIOCHEMISTRY. BIOKHIMIIA 2018; 83:863-873. [PMID: 30208826 DOI: 10.1134/s0006297918080011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/09/2018] [Indexed: 12/22/2022]
Abstract
Translation factor eIF5A participates in protein synthesis at the stage of polypeptide chain elongation. Two eIF5A isoforms are known that are encoded by related genes whose expression varies significantly in different tissues. The eIF5A1 isoform is a constitutively and ubiquitously expressed gene, while the eIF5A2 isoform is expressed in few normal tissues and is an oncogene by a number of parameters. Unique feature of eIF5A isoforms is that they are the only two proteins that contain amino acid hypusine. Modification with hypusine is critical requirement for eIF5A activity. Another distinctive feature of eIF5A is its involvement in the translation of only a subset of the total population of cell mRNAs. The genes for which mRNAs translation requires eIF5A are the members of certain functional groups and are involved in cell proliferation, apoptosis, inflammatory processes, and regulation of transcription and RNA metabolism. The involvement of eIF5A is necessary for the translation of proteins containing oligoproline fragments and some other structures. Modification of eIF5A by hypusine is implemented by two highly specialized enzymes, deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH), which are not involved in other biochemical reactions. Intracellular activity of these enzymes is closely associated with systems of protein acetylation, polyamine metabolism and other biochemical processes. Inhibition of DHS and DOHH activity provides the possibility of pharmacological control of eIF5A activity and expression of eIF5A-dependent genes.
Collapse
Affiliation(s)
- K T Turpaev
- Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia.
| |
Collapse
|
9
|
Zhou Y, Zhao L, Mei F, Hong Y, Xia H, Zuo T, Ding Y, Wang W. Macrophage migration inhibitory factor antagonist (S,R)3‑(4‑hydroxyphenyl)‑4,5‑dihydro‑5‑isoxazole acetic acid methyl ester attenuates inflammation and lung injury in rats with acute pancreatitis in pregnancy. Mol Med Rep 2018; 17:6576-6584. [PMID: 29512741 PMCID: PMC5928642 DOI: 10.3892/mmr.2018.8672] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 02/14/2018] [Indexed: 12/14/2022] Open
Abstract
Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine involved in many acute and chronic inflammatory diseases. However, its role in acute lung injury associated with acute pancreatitis in pregnancy (APIP) has not yet been elucidated. The present study was undertaken to clarify the effect and potential mechanism of MIF antagonist (S,R)3‑(4‑hydroxyphenyl)‑4,5‑dihydro‑5‑isoxazole acetic acid methyl ester (ISO‑1) in the development of acute lung injury in rats with APIP. Eighteen late‑gestation SD rats were randomly assigned to three groups: Sham operation (SO) group, APIP group, and ISO‑1 group. All the rats were sacrificed 6 h after modeling. The severity of pancreatitis was evaluated by serum amylase (AMY), lipase (LIPA), tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β and IL‑6 and assessing the histopathological score. Lung injury was determined by performing histology and inflammatory cell infiltration investigations. Western blot analysis was used to detect the protein expression of MIF, phosphorylated and total P38 and nuclear factor‑κB (NF‑κB) protein in lungs. The results showed that MIF was upregulated in the lung of APIP rats. Compared with APIP group, the intervention of ISO‑1 alleviated the pathological injury of the pancreas and lungs, decreased serum AMY and LIPA, attenuated serum concentrations of TNF‑α, IL‑1β, and IL‑6, reduced the number of MPO‑positive cells in the lung and inhibited the activation of P38MAPK and NF‑κB. These results suggest that MIF is activated in lung injury induced by APIP. Furhtermore, the present findings indicate that the MIF antagonist ISO‑1 has a protective effect on lung injury and inflammation, which may be associated with deactivating the P38MAPK and NF‑κB signaling pathway.
Collapse
Affiliation(s)
- Yu Zhou
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Liang Zhao
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Fangchao Mei
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Yupu Hong
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - He Xia
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Teng Zuo
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Youming Ding
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Weixing Wang
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| |
Collapse
|
10
|
Yoshimatsu G, Kunnathodi F, Saravanan PB, Shahbazov R, Chang C, Darden CM, Zurawski S, Boyuk G, Kanak MA, Levy MF, Naziruddin B, Lawrence MC. Pancreatic β-Cell-Derived IP-10/CXCL10 Isletokine Mediates Early Loss of Graft Function in Islet Cell Transplantation. Diabetes 2017; 66:2857-2867. [PMID: 28855240 PMCID: PMC5652609 DOI: 10.2337/db17-0578] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/22/2017] [Indexed: 01/08/2023]
Abstract
Pancreatic islets produce and secrete cytokines and chemokines in response to inflammatory and metabolic stress. The physiological role of these "isletokines" in health and disease is largely unknown. We observed that islets release multiple inflammatory mediators in patients undergoing islet transplants within hours of infusion. The proinflammatory cytokine interferon-γ-induced protein 10 (IP-10/CXCL10) was among the highest released, and high levels correlated with poor islet transplant outcomes. Transgenic mouse studies confirmed that donor islet-specific expression of IP-10 contributed to islet inflammation and loss of β-cell function in islet grafts. The effects of islet-derived IP-10 could be blocked by treatment of donor islets and recipient mice with anti-IP-10 neutralizing monoclonal antibody. In vitro studies showed induction of the IP-10 gene was mediated by calcineurin-dependent NFAT signaling in pancreatic β-cells in response to oxidative or inflammatory stress. Sustained association of NFAT and p300 histone acetyltransferase with the IP-10 gene required p38 and c-Jun N-terminal kinase mitogen-activated protein kinase (MAPK) activity, which differentially regulated IP-10 expression and subsequent protein release. Overall, these findings elucidate an NFAT-MAPK signaling paradigm for induction of isletokine expression in β-cells and reveal IP-10 as a primary therapeutic target to prevent β-cell-induced inflammatory loss of graft function after islet cell transplantation.
Collapse
Affiliation(s)
| | | | | | - Rauf Shahbazov
- Islet Cell Laboratory, Baylor Research Institute, Dallas, TX
| | - Charles Chang
- Institute of Biomedical Studies, Baylor University, Waco, TX
| | - Carly M Darden
- Institute of Biomedical Studies, Baylor University, Waco, TX
| | | | - Gulbahar Boyuk
- Adacell Medical Research Center, Department of Endocrinology and Metabolism, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Mazhar A Kanak
- Department of Surgery, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Marlon F Levy
- Department of Surgery, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Bashoo Naziruddin
- Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX
| | | |
Collapse
|
11
|
Ma K, Xiao A, Park SH, Glenn L, Jackson L, Barot T, Weaver JR, Taylor-Fishwick DA, Luci DK, Maloney DJ, Mirmira RG, Imai Y, Nadler JL. 12-Lipoxygenase Inhibitor Improves Functions of Cytokine-Treated Human Islets and Type 2 Diabetic Islets. J Clin Endocrinol Metab 2017; 102:2789-2797. [PMID: 28609824 PMCID: PMC5546865 DOI: 10.1210/jc.2017-00267] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/03/2017] [Indexed: 12/21/2022]
Abstract
CONTEXT The 12-lipoxygenase (12-LO) pathway produces proinflammatory metabolites, and its activation is implicated in islet inflammation associated with type 1 and type 2 diabetes (T2D). OBJECTIVES We aimed to test the efficacy of ML355, a highly selective, small molecule inhibitor of 12-LO, for the preservation of islet function. DESIGN Human islets from nondiabetic donors were incubated with a mixture of tumor necrosis factor α , interluekin-1β, and interferon-γ to model islet inflammation. Cytokine-treated islets and human islets from T2D donors were incubated in the presence and absence of ML355. SETTING In vitro study. PARTICIPANTS Human islets from organ donors aged >20 years of both sexes and any race were used. T2D status was defined from either medical history or most recent hemoglobin A1c value >6.5%. INTERVENTION Glucose stimulation. MAIN OUTCOME MEASURES Static and dynamic insulin secretion and oxygen consumption rate (OCR). RESULTS ML355 prevented the reduction of insulin secretion and OCR in cytokine-treated human islets and improved both parameters in human islets from T2D donors. CONCLUSIONS ML355 was efficacious in improving human islet function after cytokine treatment and in T2D islets in vitro. The study suggests that the blockade of the 12-LO pathway may serve as a target for both form of diabetes and provides the basis for further study of this small molecule inhibitor in vivo.
Collapse
Affiliation(s)
- Kaiwen Ma
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - An Xiao
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - So Hyun Park
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Lindsey Glenn
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Laura Jackson
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Tatvam Barot
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Jessica R. Weaver
- Department of Microbiology & Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - David A. Taylor-Fishwick
- Department of Microbiology & Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Diane K. Luci
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - David J. Maloney
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Raghavendra G. Mirmira
- Department of Pediatrics, IU Center for Diabetes and Metabolic Disease, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Departments of Biochemistry and Molecular Biology, Medicine, and Cellular and Integrative Physiology, IU Center for Diabetes and Metabolic Disease, Indiana University School of Medicine, Indianapolis, Indiana 46202
- Indiana Biosciences Research Institute, Indianapolis, Indiana 46202
| | - Yumi Imai
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Department of Internal Medicine, Fraternal Order of Eagles Diabetes Research Center, The University of Iowa Carver College of Medicine, Iowa City, Iowa 52242
| | - Jerry L. Nadler
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| |
Collapse
|
12
|
Takatani T, Shirakawa J, Roe MW, Leech CA, Maier BF, Mirmira RG, Kulkarni RN. IRS1 deficiency protects β-cells against ER stress-induced apoptosis by modulating sXBP-1 stability and protein translation. Sci Rep 2016; 6:28177. [PMID: 27378176 PMCID: PMC4932502 DOI: 10.1038/srep28177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/31/2016] [Indexed: 01/05/2023] Open
Abstract
Endoplasmic reticulum (ER) stress is among several pathological features that underlie β-cell failure in the development of type 1 and type 2 diabetes. Adaptor proteins in the insulin/insulin-like-growth factor-1 signaling pathways, such as insulin receptor substrate-1 (IRS1) and IRS2, differentially impact β-cell survival but the underlying mechanisms remain unclear. Here we report that β-cells deficient in IRS1 (IRS1KO) are resistant, while IRS2 deficiency (IRS2KO) makes them susceptible to ER stress-mediated apoptosis. IRS1KOs exhibited low nuclear accumulation of spliced XBP-1 due to its poor stability, in contrast to elevated accumulation in IRS2KO. The reduced nuclear accumulation in IRS1KO was due to protein instability of Xbp1 secondary to proteasomal degradation. IRS1KO also demonstrated an attenuation in their general translation status in response to ER stress revealed by polyribosomal profiling. Phosphorylation of eEF2 was dramatically increased in IRS1KO enabling the β-cells to adapt to ER stress by blocking translation. Furthermore, significantly high ER calcium (Ca2+) was detected in IRS1KO β-cells even upon induction of ER stress. These observations suggest that IRS1 could be a therapeutic target for β-cell protection against ER stress-mediated cell death by modulating XBP-1 stability, protein synthesis, and Ca2+ storage in the ER.
Collapse
Affiliation(s)
- Tomozumi Takatani
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - Jun Shirakawa
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - Michael W Roe
- Department of Medicine, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, USA
| | - Colin A Leech
- Department of Medicine, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, USA
| | - Bernhard F Maier
- Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Raghavendra G Mirmira
- Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Cellular and Integrative Physiology, Department of Biochemistry and Molecular Biology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Rohit N Kulkarni
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
13
|
Choi SB, Bae GS, Jo IJ, Wang S, Song HJ, Park SJ. Berberine inhibits inflammatory mediators and attenuates acute pancreatitis through deactivation of JNK signaling pathways. Mol Immunol 2016; 74:27-38. [PMID: 27148818 DOI: 10.1016/j.molimm.2016.04.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 04/19/2016] [Accepted: 04/26/2016] [Indexed: 01/14/2023]
Abstract
Acute pancreatitis (AP) is a life-threatening disease. Berberine (BBR), a well-known plant alkaloid, is reported to have anti-inflammatory activity in many diseases. However, the effects of BBR on AP have not been clearly elucidated. Therefore, the present study aimed to investigate the effects of BBR on cerulein-induced AP in mice. AP was induced by either cerulein or l-arginine. In the BBR treated group, BBR was administered intraperitoneally 1h before the first cerulein or l-arginine injection. Blood samples were obtained to determine serum amylase and lipase activities and nitric oxide production. The pancreas and lung were rapidly removed for examination of histologic changes, myeloperoxidase (MPO) activity, and real-time reverse transcription-polymerase chain reaction. Furthermore, the regulating mechanisms of BBR were evaluated. Treatment of mice with BBR reduced pancreatic injury and activities of amylase, lipase, and pancreatitis-associated lung injury, as well as inhibited several inflammatory parameters such as the expression of pro-inflammatory cytokines and inducible nitric oxide synthesis (iNOS). Furthermore, BBR administration significantly inhibited c-Jun N-terminal kinase (JNK) activation in the cerulein-induced AP. Deactivation of JNK resulted in amelioration of pancreatitis and the inhibition of inflammatory mediators. These results suggest that BBR exerts anti-inflammatory effects on AP via JNK deactivation on mild and severe acute pancreatitis model, and could be a beneficial target in the management of AP.
Collapse
Affiliation(s)
- Sun-Bok Choi
- BK21 Plus Team, Professional Graduate School of Oriental Medicine, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea; Department of Herbology, School of Korean Medicine, Wonkwang University, Jeonbuk Iksan 540-749, South Korea
| | - Gi-Sang Bae
- Department of Herbology, School of Korean Medicine, Wonkwang University, Jeonbuk Iksan 540-749, South Korea; Hanbang Body Fluid Research Center, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea
| | - Il-Joo Jo
- Department of Herbology, School of Korean Medicine, Wonkwang University, Jeonbuk Iksan 540-749, South Korea; Hanbang Body Fluid Research Center, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea
| | - Shaofan Wang
- School of Pharmacy, Ningxia Medical University, 1160 Shengli Street, Yinchuan, Ningxia 750004, China
| | - Ho-Joon Song
- BK21 Plus Team, Professional Graduate School of Oriental Medicine, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea; Department of Herbology, School of Korean Medicine, Wonkwang University, Jeonbuk Iksan 540-749, South Korea
| | - Sung-Joo Park
- BK21 Plus Team, Professional Graduate School of Oriental Medicine, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea; Department of Herbology, School of Korean Medicine, Wonkwang University, Jeonbuk Iksan 540-749, South Korea; Hanbang Body Fluid Research Center, Wonkwang University, Jeonbuk, Iksan 540-749, South Korea.
| |
Collapse
|
14
|
Lee WB, Kang JS, Choi WY, Zhang Q, Kim CH, Choi UY, Kim-Ha J, Kim YJ. Mincle-mediated translational regulation is required for strong nitric oxide production and inflammation resolution. Nat Commun 2016; 7:11322. [PMID: 27089465 PMCID: PMC4837483 DOI: 10.1038/ncomms11322] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 03/14/2016] [Indexed: 12/21/2022] Open
Abstract
In response to persistent mycobacteria infection, the host induces a granuloma, which often fails to eradicate bacteria and results in tissue damage. Diverse host receptors are required to control the formation and resolution of granuloma, but little is known concerning their regulatory interactions. Here we show that Mincle, the inducible receptor for mycobacterial cord factor, is the key switch for the transition of macrophages from cytokine expression to high nitric oxide production. In addition to its stimulatory role on TLR-mediated transcription, Mincle enhanced the translation of key genes required for nitric oxide synthesis through p38 and eIF5A hypusination, leading to granuloma resolution. Thus, Mincle has dual functions in the promotion and subsequent resolution of inflammation during anti-mycobacterial defence using both transcriptional and translational controls.
Collapse
Affiliation(s)
- Wook-Bin Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Ji-Seon Kang
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Won Young Choi
- Department of Integrated Omics for Biomedical Science, Graduate School, Yonsei University, Seoul 03722, Republic of Korea
| | - Quanri Zhang
- Department of Integrated Omics for Biomedical Science, Graduate School, Yonsei University, Seoul 03722, Republic of Korea
| | - Chul Han Kim
- Department of Integrated Omics for Biomedical Science, Graduate School, Yonsei University, Seoul 03722, Republic of Korea
| | - Un Yung Choi
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Jeongsil Kim-Ha
- Department of Integrative Bioscience and Biotechnology, College of Life Sciences, Sejong University, Seoul 05006, Republic of Korea
| | - Young-Joon Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
- Department of Integrated Omics for Biomedical Science, Graduate School, Yonsei University, Seoul 03722, Republic of Korea
| |
Collapse
|
15
|
Hassler JR, Scheuner DL, Wang S, Han J, Kodali VK, Li P, Nguyen J, George JS, Davis C, Wu SP, Bai Y, Sartor M, Cavalcoli J, Malhi H, Baudouin G, Zhang Y, Yates III JR, Itkin-Ansari P, Volkmann N, Kaufman RJ. The IRE1α/XBP1s Pathway Is Essential for the Glucose Response and Protection of β Cells. PLoS Biol 2015; 13:e1002277. [PMID: 26469762 PMCID: PMC4607427 DOI: 10.1371/journal.pbio.1002277] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 09/08/2015] [Indexed: 12/11/2022] Open
Abstract
Although glucose uniquely stimulates proinsulin biosynthesis in β cells, surprisingly little is known of the underlying mechanism(s). Here, we demonstrate that glucose activates the unfolded protein response transducer inositol-requiring enzyme 1 alpha (IRE1α) to initiate X-box-binding protein 1 (Xbp1) mRNA splicing in adult primary β cells. Using mRNA sequencing (mRNA-Seq), we show that unconventional Xbp1 mRNA splicing is required to increase and decrease the expression of several hundred mRNAs encoding functions that expand the protein secretory capacity for increased insulin production and protect from oxidative damage, respectively. At 2 wk after tamoxifen-mediated Ire1α deletion, mice develop hyperglycemia and hypoinsulinemia, due to defective β cell function that was exacerbated upon feeding and glucose stimulation. Although previous reports suggest IRE1α degrades insulin mRNAs, Ire1α deletion did not alter insulin mRNA expression either in the presence or absence of glucose stimulation. Instead, β cell failure upon Ire1α deletion was primarily due to reduced proinsulin mRNA translation primarily because of defective glucose-stimulated induction of a dozen genes required for the signal recognition particle (SRP), SRP receptors, the translocon, the signal peptidase complex, and over 100 other genes with many other intracellular functions. In contrast, Ire1α deletion in β cells increased the expression of over 300 mRNAs encoding functions that cause inflammation and oxidative stress, yet only a few of these accumulated during high glucose. Antioxidant treatment significantly reduced glucose intolerance and markers of inflammation and oxidative stress in mice with β cell-specific Ire1α deletion. The results demonstrate that glucose activates IRE1α-mediated Xbp1 splicing to expand the secretory capacity of the β cell for increased proinsulin synthesis and to limit oxidative stress that leads to β cell failure.
Collapse
Affiliation(s)
- Justin R. Hassler
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Donalyn L. Scheuner
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
- Lilly Research Laboratories, Eli Lilly & Company, Lilly Corporate Center, Indianapolis, Indiana, United States of America
| | - Shiyu Wang
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Jaeseok Han
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Vamsi K. Kodali
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Philip Li
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Julie Nguyen
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Jenny S. George
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Cory Davis
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Shengyang P. Wu
- Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Yongsheng Bai
- NCIBI Department of Bioinformatics, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
- Department of Biology, Indiana State University, Terre Haute, Indiana, United States of America
| | - Maureen Sartor
- NCIBI Department of Bioinformatics, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - James Cavalcoli
- NCIBI Department of Bioinformatics, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Harmeet Malhi
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
| | - Gregory Baudouin
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Yaoyang Zhang
- Department of Chemical Physiology and Cell Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - John R. Yates III
- Department of Chemical Physiology and Cell Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Pamela Itkin-Ansari
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Niels Volkmann
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
| | - Randal J. Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, United States of America
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, Michigan, United States of America
- * E-mail:
| |
Collapse
|
16
|
Divakaruni AS, Paradyse A, Ferrick DA, Murphy AN, Jastroch M. Analysis and interpretation of microplate-based oxygen consumption and pH data. Methods Enzymol 2015; 547:309-54. [PMID: 25416364 DOI: 10.1016/b978-0-12-801415-8.00016-3] [Citation(s) in RCA: 323] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Breakthrough technologies to measure cellular oxygen consumption and proton efflux are reigniting the study of cellular energetics by increasing the scope and pace with which discoveries are made. As we learn the variation in metabolism between cell types is large, it is helpful to continually provide additional perspectives and update our roadmap for data interpretation. In that spirit, this chapter provides the following for those conducting microplate-based oxygen consumption experiments: (i) a description of the standard parameters for measuring respiration in intact cells, (ii) a framework for data analysis and normalization, and (iii) examples of measuring respiration in permeabilized cells to follow up results observed with intact cells. Additionally, rate-based measurements of extracellular pH are increasingly used as a qualitative indicator of glycolytic flux. As a resource to help interpret these measurements, this chapter also provides a detailed accounting of proton production during glucose oxidation in the context of plate-based assays.
Collapse
Affiliation(s)
- Ajit S Divakaruni
- Department of Pharmacology, University of California, San Diego, California, USA.
| | - Alexander Paradyse
- Department of Pharmacology, University of California, San Diego, California, USA
| | | | - Anne N Murphy
- Department of Pharmacology, University of California, San Diego, California, USA
| | - Martin Jastroch
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| |
Collapse
|
17
|
Oleson BJ, McGraw JA, Broniowska KA, Annamalai M, Chen J, Bushkofsky JR, Davis DB, Corbett JA, Mathews CE. Distinct differences in the responses of the human pancreatic β-cell line EndoC-βH1 and human islets to proinflammatory cytokines. Am J Physiol Regul Integr Comp Physiol 2015; 309:R525-34. [PMID: 26084699 DOI: 10.1152/ajpregu.00544.2014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 06/15/2015] [Indexed: 11/22/2022]
Abstract
While insulinoma cells have been developed and proven to be extremely useful in studies focused on mechanisms controlling β-cell function and viability, translating findings to human β-cells has proven difficult because of the limited access to human islets and the absence of suitable insulinoma cell lines of human origin. Recently, a human β-cell line, EndoC-βH1, has been derived from human fetal pancreatic buds. The purpose of this study was to determine whether human EndoC-βH1 cells respond to cytokines in a fashion comparable to human islets. Unlike most rodent-derived insulinoma cell lines that respond to cytokines in a manner consistent with rodent islets, EndoC-βH1 cells fail to respond to a combination of cytokines (IL-1, IFN-γ, and TNF) in a manner consistent with human islets. Nitric oxide, produced following inducible nitric oxide synthase (iNOS) expression, is a major mediator of cytokine-induced human islet cell damage. We show that EndoC-βH1 cells fail to express iNOS or produce nitric oxide in response to this combination of cytokines. Inhibitors of iNOS prevent cytokine-induced loss of human islet cell viability; however, they do not prevent cytokine-induced EndoC-βH1 cell death. Stressed human islets or human islets expressing heat shock protein 70 (HSP70) are resistant to cytokines, and, much like stressed human islets, EndoC-βH1 cells express HSP70 under basal conditions. Elevated basal expression of HSP70 in EndoC-βH1 cells is consistent with the lack of iNOS expression in response to cytokine treatment. While expressing HSP70, EndoC-βH1 cells fail to respond to endoplasmic reticulum stress activators, such as thapsigargin. These findings indicate that EndoC-βH1 cells do not faithfully recapitulate the response of human islets to cytokines. Therefore, caution should be exercised when making conclusions regarding the actions of cytokines on human islets when using this human-derived insulinoma cell line.
Collapse
Affiliation(s)
- Bryndon J Oleson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Jennifer A McGraw
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin
| | | | - Mani Annamalai
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Jing Chen
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| | - Justin R Bushkofsky
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin, Madison, Wisconsin; and
| | - Dawn B Davis
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Wisconsin, Madison, Wisconsin; and William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin
| | - John A Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin;
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida
| |
Collapse
|
18
|
Pepin E, Higa A, Schuster-Klein C, Bernard C, Sulpice T, Guardiola B, Chevet E, Alquier T. Deletion of apoptosis signal-regulating kinase 1 (ASK1) protects pancreatic beta-cells from stress-induced death but not from glucose homeostasis alterations under pro-inflammatory conditions. PLoS One 2014; 9:e112714. [PMID: 25383781 PMCID: PMC4226582 DOI: 10.1371/journal.pone.0112714] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 10/14/2014] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Type 2 diabetes is characterized by pancreatic beta-cell dysfunction and is associated with low-grade inflammation. Recent observations suggest that apoptosis signal-regulating kinase 1 (ASK1) is involved in beta-cell death in response to different stressors. In this study, we tested whether ASK1 deficiency protects beta-cells from glucolipotoxic conditions and cytokines treatment or from glucose homeostasis alteration induced by endotoxemia. METHODOLOGY/PRINCIPAL FINDINGS Insulin secretion was neither affected upon shRNA-mediated downregulation of ASK1 in MIN6 cells nor in islets from ASK1-deficient mice. ASK1 silencing in MIN6 cells and deletion in islets did not prevent the deleterious effect of glucolipotoxic conditions or cytokines on insulin secretion. However, it protected MIN6 cells from death induced by ER stress or palmitate and islets from short term caspase activation in response to cytokines. Moreover, endotoxemia induced by LPS infusion increased insulin secretion during hyperglycemic clamps but the response was similar in wild-type and ASK1-deficient mice. Finally, insulin sensitivity in the presence of LPS was not affected by ASK1-deficiency. CONCLUSIONS/SIGNIFICANCE Our study demonstrates that ASK1 is not involved in beta-cell function and dysfunction but controls stress-induced beta-cell death.
Collapse
Affiliation(s)
| | - Arisa Higa
- Inserm U1053, Team Endoplasmic Reticulum Stress and Cancer, Université de Bordeaux, Bordeaux, France, 33076
| | | | | | - Thierry Sulpice
- Betagenex Inc, Laval, QC, Canada, H7V5B7
- Physiogenex SAS, Labège, France, 31670
| | | | - Eric Chevet
- Inserm U1053, Team Endoplasmic Reticulum Stress and Cancer, Université de Bordeaux, Bordeaux, France, 33076
| | - Thierry Alquier
- Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), and Departments of Medicine, Biochemistry and Cell Biology and Pathology, Université de Montréal, Montréal, QC, Canada, H3T 1J4
- * E-mail:
| |
Collapse
|
19
|
Hatanaka M, Maier B, Sims EK, Templin AT, Kulkarni RN, Evans-Molina C, Mirmira RG. Palmitate induces mRNA translation and increases ER protein load in islet β-cells via activation of the mammalian target of rapamycin pathway. Diabetes 2014; 63:3404-15. [PMID: 24834975 PMCID: PMC4171659 DOI: 10.2337/db14-0105] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Saturated free fatty acids (FFAs) have complex effects on the islet β-cell, acutely promoting adaptive hyperplasia but chronically impairing insulin release. The acute effects of FFAs remain incompletely defined. To elucidate these early molecular events, we incubated mouse β-cells and islets with palmitate and then studied mRNA translation by polyribosomal profiling and analyzed signaling pathways by immunoblot analysis. We found that palmitate acutely increases polyribosome occupancy of total RNA, consistent with an increase in mRNA translation. This effect on translation was attributable to activation of mammalian target of rapamycin (mTOR) pathways via L-type Ca(2+) channels but was independent of insulin signaling. Longer incubations led to depletion of polyribosome-associated RNA, consistent with activation of the unfolded protein response (UPR). Pharmacologic inhibition of mTOR suppressed both the acute effects of palmitate on mRNA translation and the chronic effects on the UPR. Islets from mice fed a high-fat diet for 7 days showed increases in polyribosome-associated RNA and phosphorylation of S6K, both consistent with activation of mTOR. Our results suggest that palmitate acutely activates mRNA translation and that this increase in protein load contributes to the later UPR.
Collapse
Affiliation(s)
- Masayuki Hatanaka
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN
| | - Bernhard Maier
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN
| | - Emily K Sims
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN
| | - Andrew T Templin
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
| | - Rohit N Kulkarni
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA
| | - Carmella Evans-Molina
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN Department of Medicine, Indiana University School of Medicine, Indianapolis, IN Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Raghavendra G Mirmira
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN Department of Medicine, Indiana University School of Medicine, Indianapolis, IN Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| |
Collapse
|
20
|
12-lipoxygenase promotes obesity-induced oxidative stress in pancreatic islets. Mol Cell Biol 2014; 34:3735-45. [PMID: 25071151 DOI: 10.1128/mcb.00157-14] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
High-fat diets lead to obesity, inflammation, and dysglycemia. 12-Lipoxygenase (12-LO) is activated by high-fat diets and catalyzes the oxygenation of cellular arachidonic acid to form proinflammatory intermediates. We hypothesized that 12-LO in the pancreatic islet is sufficient to cause dysglycemia in the setting of high-fat feeding. To test this, we generated pancreas-specific 12-LO knockout mice and studied their metabolic and molecular adaptations to high-fat diets. Whereas knockout mice and control littermates displayed identical weight gain, body fat distribution, and macrophage infiltration into fat, knockout mice exhibited greater adaptive islet hyperplasia, improved insulin secretion, and complete protection from dysglycemia. At the molecular level, 12-LO deletion resulted in increases in islet antioxidant enzymes Sod1 and Gpx1 in response to high-fat feeding. The absence or inhibition of 12-LO led to increases in nuclear Nrf2, a transcription factor responsible for activation of genes encoding antioxidant enzymes. Our data reveal a novel pathway in which islet 12-LO suppresses antioxidant enzymes and prevents the adaptive islet responses in the setting of high-fat diets.
Collapse
|
21
|
Tersey SA, Colvin SC, Maier B, Mirmira RG. Protective effects of polyamine depletion in mouse models of type 1 diabetes: implications for therapy. Amino Acids 2014; 46:633-42. [PMID: 23846959 PMCID: PMC3888834 DOI: 10.1007/s00726-013-1560-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 07/03/2013] [Indexed: 01/08/2023]
Abstract
The underlying pathophysiology of type 1 diabetes involves autoimmune-mediated islet inflammation, leading to dysfunction and death of insulin-secreting islet β cells. Recent studies have shown that polyamines, which are essential for mRNA translation, cellular replication, and the formation of the hypusine modification of eIF5A may play an important role in the progression of cellular inflammation. To test a role for polyamines in type 1 diabetes pathogenesis, we administered the ornithine decarboxylase inhibitor difluoromethylornithine to two mouse models--the low-dose streptozotocin model and the NOD model--to deplete intracellular polyamines, and administered streptozotocin to a third model, which was haploinsufficient for the gene encoding the hypusination enzyme deoxyhypusine synthase. Subsequent development of diabetes and/or glucose intolerance was monitored. In the low-dose streptozotocin mouse model, continuous difluoromethylornithine administration dose-dependently reduced the incidence of hyperglycemia and led to the preservation of β cell area, whereas in the NOD mouse model of autoimmune diabetes difluoromethylornithine reduced diabetes incidence by 50%, preserved β cell area and insulin secretion, led to reductions in both islet inflammation and potentially diabetogenic Th17 cells in pancreatic lymph nodes. Difluoromethylornithine treatment reduced hypusinated eIF5A levels in both immune cells and islets. Animals haploinsufficient for the gene encoding deoxyhypusine synthase were partially protected from hyperglycemia induced by streptozotocin. Collectively, these studies suggest that interventions that interfere with polyamine biosynthesis and/or eIF5A hypusination may represent viable approaches in the treatment of diabetes.
Collapse
MESH Headings
- Animals
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/drug therapy
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Type 1/chemically induced
- Diabetes Mellitus, Type 1/drug therapy
- Diabetes Mellitus, Type 1/metabolism
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Eflornithine/administration & dosage
- Female
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred NOD
- Mice, Knockout
- Oxidoreductases Acting on CH-NH Group Donors/deficiency
- Oxidoreductases Acting on CH-NH Group Donors/metabolism
- Peptide Initiation Factors/metabolism
- Polyamines/metabolism
- RNA-Binding Proteins/metabolism
- Streptozocin/administration & dosage
- Eukaryotic Translation Initiation Factor 5A
Collapse
Affiliation(s)
- Sarah A. Tersey
- Department of Pediatrics and the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Stephanie C. Colvin
- Department of Pediatrics and the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Bernhard Maier
- Department of Pediatrics and the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Raghavendra G. Mirmira
- Department of Pediatrics and the Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Departments of Medicine, Cellular and Integrative Physiology, and Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| |
Collapse
|
22
|
Petrella E, Pignatti L, Neri I, Facchinetti F. The l-arginine/nitric oxide pathway is impaired in overweight/obese pregnant women. Pregnancy Hypertens 2014; 4:150-5. [PMID: 26104420 DOI: 10.1016/j.preghy.2014.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/17/2014] [Accepted: 01/17/2014] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To evaluate the l-arginine/NO system and its role in insulin signaling and endothelial function during the pregnancy of women of different BMI categories. STUDY DESIGN Twelve women with BMI⩾25 were compared with 10 normal-weight women in a fasting condition after the infusion of l-arginine (20g in 3h) and after the evaluation of the flow-mediated vasodilation (FMD) of the brachial artery between the 9th-12th and 24th-27th weeks. Blood samples for insulin and nitrite/nitrate (NOx) were collected at baseline and after 1, 2 and 3h after initiating the infusion. RESULTS In both trimesters, the baseline NOx levels were similar among groups. In the 1st trimester of the lean women, there was a NOx increase in response to l-Arg (AUC: 1328; 3, 3173), which had increased by the 2nd trimester (AUC: 3884; 1905, 7686); in overweight/obese women, no responses to l-Arg were found in the 1st or 2nd trimesters. In the 1st trimester, the insulin levels were significantly reduced in both groups after l-Arg infusion. Although the insulin levels in all BMI categories were higher in the 2nd trimester, such levels during weeks 24-27 were suppressed only in normal-weight women after l-Arg infusion. The FMD was higher during both trimesters in the lean controls and was impaired in the overweight/obese subjects. CONCLUSIONS NO availability is impaired in overweight/obese women during pregnancy, which affects endothelial functioning and interferes with insulin regulation. These mechanisms could be involved in the development of hypertensive disorders and glucose intolerance in this population.
Collapse
Affiliation(s)
- Elisabetta Petrella
- Mother-Infant Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Lucrezia Pignatti
- Mother-Infant Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Isabella Neri
- Mother-Infant Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Fabio Facchinetti
- Mother-Infant Department, University of Modena and Reggio Emilia, Modena, Italy.
| |
Collapse
|
23
|
Colvin SC, Maier B, Morris DL, Tersey SA, Mirmira RG. Deoxyhypusine synthase promotes differentiation and proliferation of T helper type 1 (Th1) cells in autoimmune diabetes. J Biol Chem 2013; 288:36226-35. [PMID: 24196968 DOI: 10.1074/jbc.m113.473942] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In type 1 diabetes, cytokines arising from immune cells cause islet β cell dysfunction even before overt hyperglycemia. Deoxyhypusine synthase catalyzes the crucial hypusine modification of the factor eIF5A, which promotes the translation of a subset of mRNAs involved in cytokine responses. Here, we tested the hypothesis that deoxyhypusine synthase and, secondarily, hypusinated eIF5A contribute to the pathogenesis of type 1 diabetes using the non-obese diabetic (NOD) mouse model. Pre-diabetic NOD mice that received injections of the deoxyhypusine inhibitor N1-guanyl-1,7-diaminoheptane (GC7) demonstrated significantly improved glucose tolerance, more robust insulin secretion, and reduced insulitis compared with control animals. Analysis of tissues from treated mice revealed selective reductions in diabetogenic T helper type 1 (Th1) cells in the pancreatic lymph nodes, a primary site of antigen presentation. Isolated mouse CD90.2(+) splenocytes stimulated in vitro with anti-CD3/anti-CD28 and IL-2 to mimic autoimmune T cell activation exhibited proliferation and differentiation of CD4(+) T cell subsets (Th1, Th17, and Treg), but those treated with the deoxyhypusine synthase inhibitor GC7 showed a dose-dependent block in T cell proliferation with selective reduction in Th1 cells, similar to that observed in NOD mice. Inhibition of deoxyhypusine synthase blocked post-transcriptional expression of CD25, the high affinity IL-2 receptor α chain. Our results suggest a previously unrecognized role for deoxyhypusine synthase in promoting T cell proliferation and differentiation via regulation of CD25. Inhibition of deoxyhypusine synthase may provide a strategy for reducing diabetogenic Th1 cells and preserving β cell function in type 1 diabetes.
Collapse
Affiliation(s)
- Stephanie C Colvin
- From the Department of Pediatrics and the Herman B. Wells Center for Pediatric Research and
| | | | | | | | | |
Collapse
|
24
|
Burke SJ, Updegraff BL, Bellich RM, Goff MR, Lu D, Minkin SC, Karlstad MD, Collier JJ. Regulation of iNOS gene transcription by IL-1β and IFN-γ requires a coactivator exchange mechanism. Mol Endocrinol 2013; 27:1724-42. [PMID: 24014650 DOI: 10.1210/me.2013-1159] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The proinflammatory cytokines IL-1β and IFN-γ decrease functional islet β-cell mass in part through the increased expression of specific genes, such as inducible nitric oxide synthase (iNOS). Dysregulated iNOS protein accumulation leads to overproduction of nitric oxide, which induces DNA damage, impairs β-cell function, and ultimately diminishes cellular viability. However, the transcriptional mechanisms underlying cytokine-mediated expression of the iNOS gene are not completely understood. Herein, we demonstrated that individual mutations within the proximal and distal nuclear factor-κB sites impaired cytokine-mediated transcriptional activation. Surprisingly, mutating IFN-γ-activated site (GAS) elements in the iNOS gene promoter, which are classically responsive to IFN-γ, modulated transcriptional sensitivity to IL-1β. Transcriptional sensitivity to IL-1β was increased by generation of a consensus GAS element and decreased correspondingly with 1 or 2 nucleotide divergences from the consensus sequence. The nuclear factor-κB subunits p65 and p50 bound to the κB response elements in an IL-1β-dependent manner. IL-1β also promoted binding of serine-phosphorylated signal transducer and activator of transcription-1 (STAT1) (Ser727) but not tyrosine-phosphorylated STAT1 (Tyr701) to GAS elements. However, phosphorylation at Tyr701 was required for IFN-γ to potentiate the IL-1β response. Furthermore, coactivator p300 and coactivator arginine methyltransferase were recruited to the iNOS gene promoter with concomitant displacement of the coactivator CREB-binding protein in cells exposed to IL-1β. Moreover, these coordinated changes in factor recruitment were associated with alterations in acetylation, methylation, and phosphorylation of histone proteins. We conclude that p65 and STAT1 cooperate to control iNOS gene transcription in response to proinflammatory cytokines by a coactivator exchange mechanism. This increase in transcription is also associated with signal-specific chromatin remodeling that leads to RNA polymerase II recruitment and phosphorylation.
Collapse
Affiliation(s)
- Susan J Burke
- Department of Nutrition, University of Tennessee, 1215 Cumberland Avenue, 229 JHB, Knoxville, Tennessee 37996-1920.
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Nishiki Y, Farb TB, Friedrich J, Bokvist K, Mirmira RG, Maier B. Characterization of a novel polyclonal anti-hypusine antibody. SPRINGERPLUS 2013; 2:421. [PMID: 24024105 PMCID: PMC3765601 DOI: 10.1186/2193-1801-2-421] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 08/26/2013] [Indexed: 12/26/2022]
Abstract
The translation factor eIF5A is the only protein known to contain the amino acid hypusine, which is formed posttranslationally. Hypusinated eIF5A is necessary for cellular proliferation and responses to extracellular stressors, and has been proposed as a target for pharmacologic therapy. Here, we provide the first comprehensive characterization of a novel polyclonal antibody (IU-88) that specifically recognizes the hypusinated eIF5A. IU-88 will be useful for the investigation of eIF5A biology and for the development of assays recognizing hypusinated eIF5A.
Collapse
Affiliation(s)
- Yurika Nishiki
- Departments of Medicine, Cellular and Integrative Physiology, and Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | | | | | | | | | | |
Collapse
|