1
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Maluchenko NV, Feofanov AV, Studitsky VM. PARP-1-Associated Pathological Processes: Inhibition by Natural Polyphenols. Int J Mol Sci 2021; 22:11441. [PMID: 34768872 PMCID: PMC8584120 DOI: 10.3390/ijms222111441] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/18/2021] [Accepted: 10/21/2021] [Indexed: 02/06/2023] Open
Abstract
Poly (ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme involved in processes of cell cycle regulation, DNA repair, transcription, and replication. Hyperactivity of PARP-1 induced by changes in cell homeostasis promotes development of chronic pathological processes leading to cell death during various metabolic disorders, cardiovascular and neurodegenerative diseases. In contrast, tumor growth is accompanied by a moderate activation of PARP-1 that supports survival of tumor cells due to enhancement of DNA lesion repair and resistance to therapy by DNA damaging agents. That is why PARP inhibitors (PARPi) are promising agents for the therapy of tumor and metabolic diseases. A PARPi family is rapidly growing partly due to natural polyphenols discovered among plant secondary metabolites. This review describes mechanisms of PARP-1 participation in the development of various pathologies, analyzes multiple PARP-dependent pathways of cell degeneration and death, and discusses representative plant polyphenols, which can inhibit PARP-1 directly or suppress unwanted PARP-dependent cellular processes.
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Affiliation(s)
- Natalya V. Maluchenko
- Biology Faculty, Lomonosov Moscow State University, Lenin Hills 1/12, 119234 Moscow, Russia; (A.V.F.); (V.M.S.)
| | - Alexey V. Feofanov
- Biology Faculty, Lomonosov Moscow State University, Lenin Hills 1/12, 119234 Moscow, Russia; (A.V.F.); (V.M.S.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Mikluko-Maklaya Str., 16/10, 117997 Moscow, Russia
| | - Vasily M. Studitsky
- Biology Faculty, Lomonosov Moscow State University, Lenin Hills 1/12, 119234 Moscow, Russia; (A.V.F.); (V.M.S.)
- Fox Chase Cancer Center, Cottman Avenue 333, Philadelphia, PA 19111, USA
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2
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Therapeutic Strategies and Biomarkers to Modulate PARP Activity for Targeted Cancer Therapy. Cancers (Basel) 2020; 12:cancers12040972. [PMID: 32295316 PMCID: PMC7226473 DOI: 10.3390/cancers12040972] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/31/2020] [Accepted: 04/07/2020] [Indexed: 12/19/2022] Open
Abstract
Poly-(ADP-ribose) polymerase 1 (PARP1) is commonly known for its vital role in DNA damage response and repair. However, its enzymatic activity has been linked to a plethora of physiological and pathophysiological transactions ranging from cellular proliferation, survival and death. For instance, malignancies with BRCA1/2 mutations heavily rely on PARP activity for survival. Thus, the use of PARP inhibitors is a well-established intervention in these types of tumors. However, recent studies indicate that the therapeutic potential of attenuating PARP1 activity in recalcitrant tumors, especially where PARP1 is aberrantly overexpressed and hyperactivated, may extend its therapeutic utility in wider cancer types beyond BRCA-deficiency. Here, we discuss treatment strategies to expand the tumor-selective therapeutic application of PARP inhibitors and novel approaches with predictive biomarkers to perturb NAD+ levels and hyperPARylation that inactivate PARP in recalcitrant tumors. We also provide an overview of genetic alterations that transform non-BRCA mutant cancers to a state of "BRCAness" as potential biomarkers for synthetic lethality with PARP inhibitors. Finally, we discuss a paradigm shift for the use of novel PARP inhibitors outside of cancer treatment, where it has the potential to rescue normal cells from severe oxidative damage during ischemia-reperfusion injury induced by surgery and radiotherapy.
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3
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Chen SH, Yu X. Targeting dePARylation selectively suppresses DNA repair-defective and PARP inhibitor-resistant malignancies. SCIENCE ADVANCES 2019; 5:eaav4340. [PMID: 30989114 PMCID: PMC6457938 DOI: 10.1126/sciadv.aav4340] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 02/20/2019] [Indexed: 05/17/2023]
Abstract
While poly(ADP-ribosyl)ation (PARylation) plays an important role in DNA repair, the role of dePARylation in DNA repair remains elusive. Here, we report that a novel small molecule identified from the NCI database, COH34, specifically inhibits poly(ADP-ribose) glycohydrolase (PARG), the major dePARylation enzyme, with nanomolar potency in vitro and in vivo. COH34 binds to the catalytic domain of PARG, thereby prolonging PARylation at DNA lesions and trapping DNA repair factors. This compound induces lethality in cancer cells with DNA repair defects and exhibits antitumor activity in xenograft mouse cancer models. Moreover, COH34 can sensitize tumor cells with DNA repair defects to other DNA-damaging agents, such as topoisomerase I inhibitors and DNA-alkylating agents, which are widely used in cancer chemotherapy. Notably, COH34 also efficiently kills PARP inhibitor-resistant cancer cells. Together, our study reveals the molecular mechanism of PARG in DNA repair and provides an effective strategy for future cancer therapies.
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4
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O'Sullivan J, Tedim Ferreira M, Gagné JP, Sharma AK, Hendzel MJ, Masson JY, Poirier GG. Emerging roles of eraser enzymes in the dynamic control of protein ADP-ribosylation. Nat Commun 2019; 10:1182. [PMID: 30862789 PMCID: PMC6414514 DOI: 10.1038/s41467-019-08859-x] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 02/02/2019] [Indexed: 12/21/2022] Open
Abstract
Protein ADP-ribosylation is essential for the regulation of several cellular pathways, enabling dynamic responses to diverse pathophysiological conditions. It is modulated through a dynamic interplay between ADP-ribose readers, writers and erasers. While ADP-ribose synthesis has been studied and reviewed extensively, ADP-ribose processing by erasing enzymes has received comparably less attention. However, major progress in the mass spectrometric identification of ADP-ribosylated residues and the biochemical characterization of ADP-ribose erasers has substantially expanded our knowledge of ADP-ribosylation dynamics. Herein, we describe recent insights into the biology of ADP-ribose erasers and discuss the intricately orchestrated cellular processes to switch off ADP-ribose-dependent mechanisms. ADP-ribose erasing enzymes are increasingly recognized as critical regulators of protein ADP-ribosylation dynamics in living systems. Here, the authors review recent advances in the discovery and characterization of ADP-ribose erasers and discuss their role within the cellular ADP-ribosylation machinery.
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Affiliation(s)
- Julia O'Sullivan
- Genome Stability Laboratory, Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, HDQ Pavilion, Oncology Division, Québec, G1R 2J6, Canada.,Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, G1V 0A6, Canada
| | - Maria Tedim Ferreira
- Genome Stability Laboratory, Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, HDQ Pavilion, Oncology Division, Québec, G1R 2J6, Canada.,Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, G1V 0A6, Canada.,Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, CHUL Pavilion, Oncology division, Québec, G1V 4G2, Canada
| | - Jean-Philippe Gagné
- Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, G1V 0A6, Canada.,Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, CHUL Pavilion, Oncology division, Québec, G1V 4G2, Canada
| | - Ajit K Sharma
- Department of Oncology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, T6G 1Z2, Canada
| | - Michael J Hendzel
- Department of Oncology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, T6G 1Z2, Canada.,Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, T6G 2H7, Canada
| | - Jean-Yves Masson
- Genome Stability Laboratory, Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, HDQ Pavilion, Oncology Division, Québec, G1R 2J6, Canada.,Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, G1V 0A6, Canada.,Centre de Recherche sur le Cancer de l'Université Laval, Québec, G1R 3S3, Canada
| | - Guy G Poirier
- Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, G1V 0A6, Canada. .,Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, CHUL Pavilion, Oncology division, Québec, G1V 4G2, Canada. .,Centre de Recherche sur le Cancer de l'Université Laval, Québec, G1R 3S3, Canada.
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5
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Mashimo M, Bu X, Aoyama K, Kato J, Ishiwata-Endo H, Stevens LA, Kasamatsu A, Wolfe LA, Toro C, Adams D, Markello T, Gahl WA, Moss J. PARP1 inhibition alleviates injury in ARH3-deficient mice and human cells. JCI Insight 2019; 4:124519. [PMID: 30830864 DOI: 10.1172/jci.insight.124519] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 01/11/2019] [Indexed: 12/11/2022] Open
Abstract
Poly(ADP-ribosyl)ation refers to the covalent attachment of ADP-ribose to protein, generating branched, long chains of ADP-ribose moieties, known as poly(ADP-ribose) (PAR). Poly(ADP-ribose) polymerase 1 (PARP1) is the main polymerase and acceptor of PAR in response to DNA damage. Excessive intracellular PAR accumulation due to PARP1 activation leads cell death in a pathway known as parthanatos. PAR degradation is mainly controlled by poly(ADP-ribose) glycohydrolase (PARG) and ADP-ribose-acceptor hydrolase 3 (ARH3). Our previous results demonstrated that ARH3 confers protection against hydrogen peroxide (H2O2) exposure, by lowering cytosolic and nuclear PAR levels and preventing apoptosis-inducing factor (AIF) nuclear translocation. We identified a family with an ARH3 gene mutation that resulted in a truncated, inactive protein. The 8-year-old proband exhibited a progressive neurodegeneration phenotype. In addition, parthanatos was observed in neurons of the patient's deceased sibling, and an older sibling exhibited a mild behavioral phenotype. Consistent with the previous findings, the patient's fibroblasts and ARH3-deficient mice were more sensitive, respectively, to H2O2 stress and cerebral ischemia/reperfusion-induced PAR accumulation and cell death. Further, PARP1 inhibition alleviated cell death and injury resulting from oxidative stress and ischemia/reperfusion. PARP1 inhibitors may attenuate the progression of neurodegeneration in affected patients with ARH3 deficiency.
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Affiliation(s)
- Masato Mashimo
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
| | - Xiangning Bu
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
| | - Kazumasa Aoyama
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
| | - Jiro Kato
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
| | | | - Linda A Stevens
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
| | | | - Lynne A Wolfe
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, and
| | - Camilo Toro
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, and
| | - David Adams
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, and.,Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, Maryland, USA
| | - Thomas Markello
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, and
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, and.,Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, Maryland, USA
| | - Joel Moss
- Pulmonary Branch, National Heart, Lung, and Blood Institute (NHLBI)
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6
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Chowdhury P, Nagesh PKB, Hatami E, Wagh S, Dan N, Tripathi MK, Khan S, Hafeez BB, Meibohm B, Chauhan SC, Jaggi M, Yallapu MM. Tannic acid-inspired paclitaxel nanoparticles for enhanced anticancer effects in breast cancer cells. J Colloid Interface Sci 2019; 535:133-148. [PMID: 30292104 PMCID: PMC6992213 DOI: 10.1016/j.jcis.2018.09.072] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/20/2018] [Accepted: 09/21/2018] [Indexed: 12/21/2022]
Abstract
Paclitaxel (PTX) is a gold standard chemotherapeutic agent for breast, ovarian, pancreatic and non-small cell lung carcinoma. However, in clinical use PTX can have adverse side effects or inadequate pharmacodynamic parameters, limiting its use. Nanotechnology is often employed to reduce the therapeutic dosage required for effective therapy, while also minimizing the systemic side effects of chemotherapy drugs. However, there is no nanoformulation of paclitaxel with chemosensitization motifs built in. With this objective, we screened eleven pharmaceutical excipients to develop an alternative paclitaxel nanoformulation using a self-assembly method. Based on the screening results, we observed tannic acid possesses unique properties to produce a paclitaxel nanoparticle formulation, i.e., tannic acid-paclitaxel nanoparticles. This stable TAP nanoformulation, referred to as TAP nanoparticles (TAP NPs), showed a spherical shape of ~ 102 nm and negative zeta potential of ~ -8.85. The presence of PTX in TAP NPs was confirmed by Fourier Transform Infrared (FTIR) spectra, thermogravimetric analyzer (TGA), and X-ray diffraction (XRD). Encapsulation efficiency of PTX in TAP NPs was determined to be ≥96%. Intracellular drug uptake of plain drug PTX on breast cancer cells (MDA-MB-231) shows more or less constant drug levels in 2 to 6 h, suggesting drug efflux by the P-gp transporters, over TAP NPs, in which PTX uptake was more than 95.52 ± 11.01% in 6 h, as analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Various biological assays such as proliferation, clonogenic formation, invasion, and migration confirm superior anticancer effects of TAP NPs over plain PTX at all tested concentrations. P-gp expression, beta-tubulin stabilization, Western blot, and microarray analysis further confirm the improved therapeutic potential of TAP NPs. These results suggest that the TAP nanoformulation provides an important reference for developing a therapeutic nanoformulation affording pronounced, enhanced effects in breast cancer therapy.
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Affiliation(s)
- Pallabita Chowdhury
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Prashanth K B Nagesh
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Elham Hatami
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Santosh Wagh
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Nirnoy Dan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Manish K Tripathi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Sheema Khan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Bilal B Hafeez
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Bernd Meibohm
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Subhash C Chauhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Meena Jaggi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Murali M Yallapu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA.
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7
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Multi-targeted Effect of Nicotinamide Mononucleotide on Brain Bioenergetic Metabolism. Neurochem Res 2019; 44:2280-2287. [PMID: 30661231 DOI: 10.1007/s11064-019-02729-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/11/2019] [Indexed: 01/04/2023]
Abstract
Dysfunctions in NAD+ metabolism are associated with neurodegenerative diseases, acute brain injury, diabetes, and aging. Loss of NAD+ levels results in impairment of mitochondria function, which leads to failure of essential metabolic processes. Strategies to replenish depleted NAD+ pools can offer significant improvements of pathologic states. NAD+ levels are maintained by two opposing enzymatic reactions, one is the consumption of NAD+ while the other is the re-synthesis of NAD+. Inhibition of NAD+ degrading enzymes, poly-ADP-ribose polymerase 1 (PARP1) and ectoenzyme CD38, following brain ischemic insult can provide neuroprotection. Preservation of NAD+ pools by administration of NAD+ precursors, such as nicotinamide (Nam) or nicotinamide mononucleotide (NMN), also offers neuroprotection. However, NMN treatment demonstrates to be a promising candidate as a therapeutic approach due to its multi-targeted effect acting as PARP1 and CD38 inhibitor, sirtuins activator, mitochondrial fission inhibitor, and NAD+ supplement. Many neurodegenerative diseases or acute brain injury activate several cellular death pathways requiring a treatment strategy that will target these mechanisms. Since NMN demonstrated the ability to exert its effect on several cellular metabolic pathways involved in brain pathophysiology it seems to be one of the most promising candidates to be used for successful neuroprotection.
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8
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Waszkowycz B, Smith KM, McGonagle AE, Jordan AM, Acton B, Fairweather EE, Griffiths LA, Hamilton NM, Hamilton NS, Hitchin JR, Hutton CP, James DI, Jones CD, Jones S, Mould DP, Small HF, Stowell AIJ, Tucker JA, Waddell ID, Ogilvie DJ. Cell-Active Small Molecule Inhibitors of the DNA-Damage Repair Enzyme Poly(ADP-ribose) Glycohydrolase (PARG): Discovery and Optimization of Orally Bioavailable Quinazolinedione Sulfonamides. J Med Chem 2018; 61:10767-10792. [PMID: 30403352 DOI: 10.1021/acs.jmedchem.8b01407] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
DNA damage repair enzymes are promising targets in the development of new therapeutic agents for a wide range of cancers and potentially other diseases. The enzyme poly(ADP-ribose) glycohydrolase (PARG) plays a pivotal role in the regulation of DNA repair mechanisms; however, the lack of potent drug-like inhibitors for use in cellular and in vivo models has limited the investigation of its potential as a novel therapeutic target. Using the crystal structure of human PARG in complex with the weakly active and cytotoxic anthraquinone 8a, novel quinazolinedione sulfonamides PARG inhibitors have been identified by means of structure-based virtual screening and library design. 1-Oxetan-3-ylmethyl derivatives 33d and 35d were selected for preliminary investigations in vivo. X-ray crystal structures help rationalize the observed structure-activity relationships of these novel inhibitors.
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Affiliation(s)
- Bohdan Waszkowycz
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Kate M Smith
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Alison E McGonagle
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Allan M Jordan
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Ben Acton
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Emma E Fairweather
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Louise A Griffiths
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Niall M Hamilton
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Nicola S Hamilton
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - James R Hitchin
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Colin P Hutton
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Dominic I James
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Clifford D Jones
- Oncology Innovative Medicines Unit , AstraZeneca , Alderley Park , Macclesfield Cheshire SK10 4TG , U.K
| | - Stuart Jones
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Daniel P Mould
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Helen F Small
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Alexandra I J Stowell
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Julie A Tucker
- Structure and Biophysics, Discovery Sciences , AstraZeneca , Alderley Park , Macclesfield , Cheshire SK10 4TG , U.K
| | - Ian D Waddell
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
| | - Donald J Ogilvie
- Cancer Research UK Manchester Institute , The University of Manchester , Alderley Park , Maccelsfield SK10 4TG , U.K
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9
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Comprehensive analysis of telomerase inhibition by gallotannin. Oncotarget 2018; 9:18712-18719. [PMID: 29721155 PMCID: PMC5922349 DOI: 10.18632/oncotarget.24642] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 02/24/2018] [Indexed: 11/25/2022] Open
Abstract
Gallotannin (or tannic acid) is a naturally occurring compound that inhibits cell growth and activity of different DNA-polymerases, including telomerase. The purpose of the present study was to gain insight into the mechanism of telomerase inhibition by gallotannin. We determined that gallotannin inhibits telomerase in vitro with an half maximal inhibitory concentrations value of 130 nM, but it does not affect telomerase complex assembly and component levels in vivo. The inhibitory activity of gallotannin against telomerase provides an additional explanation for the anti-cancer activities of this compound.
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10
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Biochemical and genetic analysis of a unique poly(ADP-ribosyl) glycohydrolase (PARG) of the pathogenic fungus Fusarium oxysporum f. sp. lycopersici. Antonie Van Leeuwenhoek 2018; 111:285-295. [DOI: 10.1007/s10482-017-0951-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 09/20/2017] [Indexed: 10/18/2022]
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11
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Rotin LE, Gronda M, MacLean N, Hurren R, Wang X, Lin FH, Wrana J, Datti A, Barber DL, Minden MD, Slassi M, Schimmer AD. Ibrutinib synergizes with poly(ADP-ribose) glycohydrolase inhibitors to induce cell death in AML cells via a BTK-independent mechanism. Oncotarget 2016; 7:2765-79. [PMID: 26624983 PMCID: PMC4823070 DOI: 10.18632/oncotarget.6409] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/16/2015] [Indexed: 12/15/2022] Open
Abstract
Targeting Bruton's tyrosine kinase (BTK) with the small molecule BTK inhibitor ibrutinib has significantly improved patient outcomes in several B-cell malignancies, with minimal toxicity. Given the reported expression and constitutive activation of BTK in acute myeloid leukemia (AML) cells, there has been recent interest in investigating the anti-AML activity of ibrutinib. We noted that ibrutinib had limited single-agent toxicity in a panel of AML cell lines and primary AML samples, and therefore sought to identify ibrutinib-sensitizing drugs. Using a high-throughput combination chemical screen, we identified that the poly(ADP-ribose) glycohydrolase (PARG) inhibitor ethacridine lactate synergized with ibrutinib in TEX and OCI-AML2 leukemia cell lines. The combination of ibrutinib and ethacridine induced a synergistic increase in reactive oxygen species that was functionally important to explain the observed cell death. Interestingly, synergistic cytotoxicity of ibrutinib and ethacridine was independent of the inhibitory effect of ibrutinib against BTK, as knockdown of BTK did not sensitize TEX and OCI-AML2 cells to ethacridine treatment. Thus, our findings indicate that ibrutinib may have a BTK-independent role in AML and that PARG inhibitors may have utility as part of a combination therapy for this disease.
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Affiliation(s)
- Lianne E Rotin
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Marcela Gronda
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Neil MacLean
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Rose Hurren
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - XiaoMing Wang
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Feng-Hsu Lin
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Jeff Wrana
- Samuel Lunenfeld Research Institute, Toronto, Ontario, Canada
| | - Alessandro Datti
- Samuel Lunenfeld Research Institute, Toronto, Ontario, Canada.,Department of Agricultural, Food, and Environmental Sciences, University of Perugia, Perugia, Italy
| | - Dwayne L Barber
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada
| | - Mark D Minden
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | | | - Aaron D Schimmer
- Princess Margaret Cancer Centre, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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12
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Stowell AIJ, James DI, Waddell ID, Bennett N, Truman C, Hardern IM, Ogilvie DJ. A high-throughput screening-compatible homogeneous time-resolved fluorescence assay measuring the glycohydrolase activity of human poly(ADP-ribose) glycohydrolase. Anal Biochem 2016; 503:58-64. [PMID: 27036617 DOI: 10.1016/j.ab.2016.03.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/17/2016] [Accepted: 03/21/2016] [Indexed: 11/30/2022]
Abstract
Poly(ADP-ribose) (PAR) polymers are transient post-translational modifications, and their formation is catalyzed by poly(ADP-ribose) polymerase (PARP) enzymes. A number of PARP inhibitors are in advanced clinical development for BRCA-mutated breast cancer, and olaparib has recently been approved for BRCA-mutant ovarian cancer; however, there has already been evidence of developed resistance mechanisms. Poly(ADP-ribose) glycohydrolase (PARG) catalyzes the hydrolysis of the endo- and exo-glycosidic bonds within the PAR polymers. As an alternative strategy, PARG is a potentially attractive therapeutic target. There is only one PARG gene, compared with 17 known PARP family members, and therefore a PARG inhibitor may have wider application with fewer compensatory mechanisms. Prior to the initiation of this project, there were no known existing cell-permeable small molecule PARG inhibitors for use as tool compounds to assess these hypotheses and no suitable high-throughput screening (HTS)-compatible biochemical assays available to identify start points for a drug discovery project. The development of this newly described high-throughput homogeneous time-resolved fluorescence (HTRF) assay has allowed HTS to proceed and, from this, the identification and advancement of multiple validated series of tool compounds for PARG inhibition.
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Affiliation(s)
- Alexandra I J Stowell
- Cancer Research UK Manchester Institute Drug Discovery Unit, University of Manchester, Manchester M20 4BX, UK.
| | - Dominic I James
- Cancer Research UK Manchester Institute Drug Discovery Unit, University of Manchester, Manchester M20 4BX, UK
| | - Ian D Waddell
- Cancer Research UK Manchester Institute Drug Discovery Unit, University of Manchester, Manchester M20 4BX, UK
| | - Neil Bennett
- Discovery Sciences, AstraZeneca, Alderley Park, Cheshire SK10 4TG, UK
| | - Caroline Truman
- Discovery Sciences, AstraZeneca, Alderley Park, Cheshire SK10 4TG, UK
| | - Ian M Hardern
- Discovery Sciences, AstraZeneca, Alderley Park, Cheshire SK10 4TG, UK
| | - Donald J Ogilvie
- Cancer Research UK Manchester Institute Drug Discovery Unit, University of Manchester, Manchester M20 4BX, UK
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13
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James DI, Durant S, Eckersley K, Fairweather E, Griffiths LA, Hamilton N, Kelly P, O'Connor M, Shea K, Waddell ID, Ogilvie DJ. An assay to measure poly(ADP ribose) glycohydrolase (PARG) activity in cells. F1000Res 2016; 5:736. [PMID: 27610220 PMCID: PMC4995692 DOI: 10.12688/f1000research.8463.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/18/2016] [Indexed: 01/06/2023] Open
Abstract
After a DNA damage signal multiple polymers of ADP ribose attached to poly(ADP) ribose (PAR) polymerases (PARPs) are broken down by the enzyme poly(ADP) ribose glycohydrolase (PARG). Inhibition of PARG leads to a failure of DNA repair and small molecule inhibition of PARG has been a goal for many years. To determine whether biochemical inhibitors of PARG are active in cells we have designed an immunofluorescence assay to detect nuclear PAR after DNA damage. This 384-well assay is suitable for medium throughput high-content screening and can detect cell-permeable inhibitors of PARG from nM to µM potency. In addition, the assay has been shown to work in murine cells and in a variety of human cancer cells. Furthermore, the assay is suitable for detecting the DNA damage response induced by treatment with temozolomide and methylmethane sulfonate (MMS). Lastly, the assay has been shown to be robust over a period of several years.
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Affiliation(s)
- Dominic I. James
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Stephen Durant
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Kay Eckersley
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Emma Fairweather
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Louise A. Griffiths
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Nicola Hamilton
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Paul Kelly
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Mark O'Connor
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Kerry Shea
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Ian D. Waddell
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Donald J. Ogilvie
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
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James DI, Durant S, Eckersley K, Fairweather E, Griffiths LA, Hamilton N, Kelly P, O'Connor M, Shea K, Waddell ID, Ogilvie DJ. An assay to measure poly(ADP ribose) glycohydrolase (PARG) activity in cells. F1000Res 2016; 5:736. [PMID: 27610220 PMCID: PMC4995692 DOI: 10.12688/f1000research.8463.2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/13/2016] [Indexed: 12/23/2022] Open
Abstract
After a DNA damage signal multiple polymers of ADP ribose attached to poly(ADP) ribose (PAR) polymerases (PARPs) are broken down by the enzyme poly(ADP) ribose glycohydrolase (PARG). Inhibition of PARG leads to a failure of DNA repair and small molecule inhibition of PARG has been a goal for many years. To determine whether biochemical inhibitors of PARG are active in cells we have designed an immunofluorescence assay to detect nuclear PAR after DNA damage. This 384-well assay is suitable for medium throughput high-content screening and can detect cell-permeable inhibitors of PARG from nM to µM potency. In addition, the assay has been shown to work in murine cells and in a variety of human cancer cells. Furthermore, the assay is suitable for detecting the DNA damage response induced by treatment with temozolomide and methylmethane sulfonate (MMS). Lastly, the assay has been shown to be robust over a period of several years.
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Affiliation(s)
- Dominic I. James
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Stephen Durant
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Kay Eckersley
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Emma Fairweather
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Louise A. Griffiths
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Nicola Hamilton
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Paul Kelly
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Mark O'Connor
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Kerry Shea
- Oncology iMED, AstraZeneca Pharmaceuticals, Macclesfield, UK
| | - Ian D. Waddell
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - Donald J. Ogilvie
- Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
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Zeng Y, Dou D, Zhang Y, Zhang L, Sun Y. Rare Sugars and Antioxidants inItea virginica, Itea oblonga Hand.-Mazz.,andItea yunnanensis FranchLeaves. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2014. [DOI: 10.1080/10942912.2014.917099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Poly(ADP-ribosyl) glycohydrolase prevents the accumulation of unusual replication structures during unperturbed S phase. Mol Cell Biol 2014; 35:856-65. [PMID: 25535335 DOI: 10.1128/mcb.01077-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Poly(ADP-ribosyl)ation (PAR) has been implicated in various aspects of the cellular response to DNA damage and genome stability. Although 17 human poly(ADP-ribose) polymerase (PARP) genes have been identified, a single poly(ADP-ribosyl) glycohydrolase (PARG) mediates PAR degradation. Here we investigated the role of PARG in the replication of human chromosomes. We show that PARG depletion affects cell proliferation and DNA synthesis, leading to replication-coupled H2AX phosphorylation. Furthermore, PARG depletion or inhibition per se slows down individual replication forks similarly to mild chemotherapeutic treatment. Electron microscopic analysis of replication intermediates reveals marked accumulation of reversed forks and single-stranded DNA (ssDNA) gaps in unperturbed PARG-defective cells. Intriguingly, while we found no physical evidence for chromosomal breakage, PARG-defective cells displayed both ataxia-telangiectasia-mutated (ATM) and ataxia-Rad3-related (ATR) activation, as well as chromatin recruitment of standard double-strand-break-repair factors, such as 53BP1 and RAD51. Overall, these data prove PAR degradation to be essential to promote resumption of replication at endogenous and exogenous lesions, preventing idle recruitment of repair factors to remodeled replication forks. Furthermore, they suggest that fork remodeling and restarting are surprisingly frequent in unperturbed cells and provide a molecular rationale to explore PARG inhibition in cancer chemotherapy.
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17
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Islam R, Koizumi F, Kodera Y, Inoue K, Okawara T, Masutani M. Design and synthesis of phenolic hydrazide hydrazones as potent poly(ADP-ribose) glycohydrolase (PARG) inhibitors. Bioorg Med Chem Lett 2014; 24:3802-6. [DOI: 10.1016/j.bmcl.2014.06.065] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 06/18/2014] [Accepted: 06/21/2014] [Indexed: 10/25/2022]
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18
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Felici R, Lapucci A, Ramazzotti M, Chiarugi A. Insight into molecular and functional properties of NMNAT3 reveals new hints of NAD homeostasis within human mitochondria. PLoS One 2013; 8:e76938. [PMID: 24155910 PMCID: PMC3796565 DOI: 10.1371/journal.pone.0076938] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 08/30/2013] [Indexed: 11/23/2022] Open
Abstract
Among the enzymes involved in NAD homeostasis, nicotinamide mononucleotide adenylyltransferases (NMNAT1-3) are central to intracellular NAD formation. Although NMNAT3 is postulated to be a mitochondrial enzyme contributing to NAD-dependent organelle functioning, information on endogenous proteins is lacking. We report that in human cells a single gene nmnat3 localized on chromosome 3 codes for two mRNA splice variants NMNATv1 and FKSG76, whereas the previously reported NMNAT3v2 transcript is not present. However, NMNAT3v1 and FKSG76 proteins are not detectable, consistent with the finding that an upstream ORF in their mRNAs negatively regulates translation. NMNAT3v1 transfection demonstrates that the protein is cytosolic and inactive, whereas FKSG76 is mitochondrial but operates NAD cleavage rather than synthesis. In keeping with the lack of NMNAT3, we show that extracellular NAD, but not its metabolic precursors, sustains mitochondrial NAD pool in an ATP-independent manner. Data of the present study modify the scenario of the origin of mitochondrial NAD by showing that, in human cells, NMNAT3 is absent in mitochondria, and, akin to plants and yeast, cytosolic NAD maintains the mitochondrial NAD pool.
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Affiliation(s)
- Roberta Felici
- Department of Health Sciences, University of Florence, Florence, Italy
- * E-mail:
| | - Andrea Lapucci
- Department of Health Sciences, University of Florence, Florence, Italy
| | - Matteo Ramazzotti
- Department of Health Sciences, University of Florence, Florence, Italy
| | - Alberto Chiarugi
- Department of Health Sciences, University of Florence, Florence, Italy
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19
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Vilchez Larrea SC, Schlesinger M, Kevorkian ML, Flawiá MM, Alonso GD, Fernández Villamil SH. Host cell poly(ADP-ribose) glycohydrolase is crucial for Trypanosoma cruzi infection cycle. PLoS One 2013; 8:e67356. [PMID: 23776710 PMCID: PMC3680488 DOI: 10.1371/journal.pone.0067356] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 05/16/2013] [Indexed: 12/21/2022] Open
Abstract
Trypanosoma cruzi, etiological agent of Chagas’ disease, has a complex life cycle which involves the invasion of mammalian host cells, differentiation and intracellular replication. Here we report the first insights into the biological role of a poly(ADP-ribose) glycohydrolase in a trypanosomatid (TcPARG). In silico analysis of the TcPARG gene pointed out the conservation of key residues involved in the catalytic process and, by Western blot, we demonstrated that it is expressed in a life stage-dependant manner. Indirect immunofluorescence assays and electron microscopy using an anti-TcPARG antibody showed that this enzyme is localized in the nucleus independently of the presence of DNA damage or cell cycle stage. The addition of poly(ADP-ribose) glycohydrolase inhibitors ADP-HPD (adenosine diphosphate (hydroxymethyl) pyrrolidinediol) or DEA (6,9-diamino-2-ethoxyacridine lactate monohydrate) to the culture media, both at a 1 µM concentration, reduced in vitro epimastigote growth by 35% and 37% respectively, when compared to control cultures. We also showed that ADP-HPD 1 µM can lead to an alteration in the progression of the cell cycle in hydroxyurea synchronized cultures of T. cruzi epimastigotes. Outstandingly, here we demonstrate that the lack of poly(ADP-ribose) glycohydrolase activity in Vero and A549 host cells, achieved by chemical inhibition or iRNA, produces the reduction of the percentage of infected cells as well as the number of amastigotes per cell and trypomastigotes released, leading to a nearly complete abrogation of the infection process. We conclude that both, T. cruzi and the host, poly(ADP-ribose) glycohydrolase activities are important players in the life cycle of Trypanosoma cruzi, emerging as a promising therapeutic target for the treatment of Chagas’ disease.
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Affiliation(s)
- Salomé C. Vilchez Larrea
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - Mariana Schlesinger
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - María L. Kevorkian
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - Mirtha M. Flawiá
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Guillermo D. Alonso
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Silvia H. Fernández Villamil
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres”, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
- * E-mail:
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20
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Feng X, Koh DW. Roles of poly(ADP-ribose) glycohydrolase in DNA damage and apoptosis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 304:227-81. [PMID: 23809438 DOI: 10.1016/b978-0-12-407696-9.00005-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Poly(ADP-ribose) glycohydrolase (PARG) is the primary enzyme that catalyzes the hydrolysis of poly(ADP-ribose) (PAR), an essential biopolymer that is synthesized by poly(ADP-ribose) polymerases (PARPs) in the cell. By regulating the hydrolytic arm of poly(ADP-ribosyl)ation, PARG participates in a number of biological processes, including the repair of DNA damage, chromatin dynamics, transcriptional regulation, and cell death. Collectively, the research investigating the roles of PARG in the cell has identified the importance of PARG and its value as a therapeutic target. However, the biological role of PARG remains less understood than the role of PAR synthesis by the PARPs. Further complicating the study of PARG is the existence of multiple PARG isoforms in the cell, the lack of optimal PARG inhibitors, and the lack of viable PARG-null animals. This review will present our current knowledge of PARG, with a focus on its roles in DNA-damage repair and cell death.
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Affiliation(s)
- Xiaoxing Feng
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, Washington, USA
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21
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The Sound of Silence: RNAi in Poly (ADP-Ribose) Research. Genes (Basel) 2012; 3:779-805. [PMID: 24705085 PMCID: PMC3899979 DOI: 10.3390/genes3040779] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 11/05/2012] [Accepted: 11/06/2012] [Indexed: 02/07/2023] Open
Abstract
Poly(ADP-ribosyl)-ation is a nonprotein posttranslational modification of proteins and plays an integral part in cell physiology and pathology. The metabolism of poly(ADP-ribose) (PAR) is regulated by its synthesis by poly(ADP-ribose) polymerases (PARPs) and on the catabolic side by poly(ADP-ribose) glycohydrolase (PARG). PARPs convert NAD+ molecules into PAR chains that interact covalently or noncovalently with target proteins and thereby modify their structure and functions. PAR synthesis is activated when PARP1 and PARP2 bind to DNA breaks and these two enzymes account for almost all PAR formation after genotoxic stress. PARG cleaves PAR molecules into free PAR and finally ADP-ribose (ADPR) moieties, both acting as messengers in cellular stress signaling. In this review, we discuss the potential of RNAi to manipulate the levels of PARPs and PARG, and consequently those of PAR and ADPR, and compare the results with those obtained after genetic or chemical disruption.
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22
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Pan J, Fauzee NJS, Wang YL, Sheng YT, Tang Y, Wang JQ, Wu WQ, Yan JX, Xu J. Effect of silencing PARG in human colon carcinoma LoVo cells on the ability of HUVEC migration and proliferation. Cancer Gene Ther 2012; 19:715-22. [PMID: 22918473 DOI: 10.1038/cgt.2012.48] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Our aim was to investigate the influence of silencing poly-(ADP-ribose)glycohydrolase (PARG) in human colon carcinoma LoVo cells on the ability of human umbilical vein endothelial cell (HUVEC) migration, proliferation and its possible mechanisms. PARG mRNA expression was detected by reverse transcriptase (RT) and real-time-PCR. PARG, poly-(ADP-ribose)polymerase (PARP), p38, p-p38, extracellular signal-regulated kinase (ERK), p-ERK, nuclear factor (NF)-κB, phosphorylated IκBα (p-IκBα), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b-FGF), intercellular cell adhesion molecule (ICAM)-1 and matrix metalloproteinases (MMP)-9 expressions were detected by western blot. The influence of PARG-short hairpin (sh)RNA on the ability of HUVEC migration and proliferation were observed by transwell migration and Counting Kit-8 (CCK-8) assay. Both RT-PCR and western blot results showed that the expression of PARG in PARG-shRNA cells was decreased and expressions of PARP, p38, p-p38, ERK, p-ERK, NF-κB, p-IκBα, VEGF, b-FGF, ICAM-1 and MMP-9 in those cells were lower than that in the untransfected and control-shRNA groups (P<0.05). Migration assay showed that migratory inhibition rate for HUVEC was decreased (55.23%) in cocultured PARG-shRNA cells; moreover, CCK-8 assay showed that the proliferation of HUVECs cultured with the supernatant of PARG-shRNA cells was also comparatively lower. Hence, concluding that PARG silencing could inhibit the ability of HUVEC migration and proliferation by downregulating the activity of NF-κB in LoVo cells that in turn decreases angiogenic factors such as VEGF, b-FGF, ICAM-1, MMP-9, as well as phosphorylation of p38 and ERK.
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Affiliation(s)
- J Pan
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, China
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23
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Fathers C, Drayton RM, Solovieva S, Bryant HE. Inhibition of poly(ADP-ribose) glycohydrolase (PARG) specifically kills BRCA2-deficient tumor cells. Cell Cycle 2012; 11:990-7. [PMID: 22333589 DOI: 10.4161/cc.11.5.19482] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Poly(ADP-ribose) glycohydrolase (PARG), removes poly(ADP-ribose) subunits from proteins that have previously been modified by poly(ADP-ribose) polymerse. This ensures that modification is transient, and it is suggested that removal of poly(ADP-ribose) is essential for some types of DNA repair. Here we show increased γH2AX foci formation and increased homologous recombination when PARG is inhibited. These effects are reduced when replication is inhibited, suggesting that in the absence of PARG activity, replication forks collapse, and homologous recombination is induced for repair. Consistent with this, we show that cells deficient in the homologous recombination protein BRCA2 are sensitive to PARG depletion or inhibition. These data raise the exciting possibility that PARG inhibitors may be used to specifically kill BRCA2 and other homologous recombination-deficient tumors.
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Affiliation(s)
- Catherine Fathers
- The Institute for Cancer Studies, Department of Oncology, Faculty of Medicine Dentistry and Health Sciences, University of Sheffield, Sheffield, UK
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24
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Briggs AG, Bent AF. Poly(ADP-ribosyl)ation in plants. TRENDS IN PLANT SCIENCE 2011; 16:372-80. [PMID: 21482174 DOI: 10.1016/j.tplants.2011.03.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Revised: 03/07/2011] [Accepted: 03/09/2011] [Indexed: 05/03/2023]
Abstract
Poly(ADP-ribose) polymerases (PARPs) and poly(ADP-ribose) glycohydrolases (PARGs) are the main enzymes responsible for the post-translational modification known as poly(ADP-ribosyl)ation. These enzymes play important roles in genotoxic stress tolerance and DNA repair, programmed cell death, transcription, and cell cycle control in animals. Similar impacts are being discovered in plants, as well as roles in plant-specific processes. In particular, we review recent work that has revealed significant roles for poly(ADP-ribosyl)ation in plant responses to biotic and abiotic stress, as well as roles for ADP-ribose pyrophosphatases (a subset of the nucleoside diphosphate linked to some moiety-X or NUDX hydrolases). Future challenges include identification of poly(ADP-ribosyl)ation targets and interacting proteins, improved use of inhibitors and plant mutants, and field-based studies with economically valuable plant species.
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Affiliation(s)
- Amy G Briggs
- Program in Cellular and Molecular Biology, University of Wisconsin - Madison, WI, USA
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25
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Tikoo K, Sane MS, Gupta C. Tannic acid ameliorates doxorubicin-induced cardiotoxicity and potentiates its anti-cancer activity: Potential role of tannins in cancer chemotherapy. Toxicol Appl Pharmacol 2011; 251:191-200. [DOI: 10.1016/j.taap.2010.12.012] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Revised: 12/17/2010] [Accepted: 12/20/2010] [Indexed: 11/27/2022]
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26
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Blenn C, Wyrsch P, Althaus FR. The ups and downs of tannins as inhibitors of poly(ADP-ribose)glycohydrolase. Molecules 2011; 16:1854-77. [PMID: 21343889 PMCID: PMC6259645 DOI: 10.3390/molecules16021854] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 02/17/2011] [Indexed: 01/21/2023] Open
Abstract
DNA damage to cells activates nuclear poly(ADP-ribose)polymerases (PARPs) and the poly(ADP-ribose) (PAR) synthesized is rapidly cleaved into ADP-ribose (ADPR) by PAR glycohydrolase (PARG) action. Naturally appearing tannin-like molecules have been implicated in specific inhibition of the PARG enzyme. This review deals with the in vitro and in vivo effects of tannins on PAR metabolism and their downstream actions in DNA damage signaling.
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Affiliation(s)
- Christian Blenn
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
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27
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Poly(ADP-ribose)glycohydrolase is an upstream regulator of Ca2+ fluxes in oxidative cell death. Cell Mol Life Sci 2010; 68:1455-66. [PMID: 20878536 PMCID: PMC3064896 DOI: 10.1007/s00018-010-0533-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 08/18/2010] [Accepted: 09/07/2010] [Indexed: 12/17/2022]
Abstract
Oxidative DNA damage to cells activates poly(ADP-ribose)polymerase-1 (PARP-1) and the poly(ADP-ribose) formed is rapidly degraded to ADP-ribose by poly(ADP-ribose)glycohydrolase (PARG). Here we show that PARP-1 and PARG control extracellular Ca2+ fluxes through melastatin-like transient receptor potential 2 channels (TRPM2) in a cell death signaling pathway. TRPM2 activation accounts for essentially the entire Ca2+ influx into the cytosol, activating caspases and causing the translocation of apoptosis inducing factor (AIF) from the inner mitochondrial membrane to the nucleus followed by cell death. Abrogation of PARP-1 or PARG function disrupts these signals and reduces cell death. ADP-ribose-loading of cells induces Ca2+ fluxes in the absence of oxidative damage, suggesting that ADP-ribose is the key metabolite of the PARP-1/PARG system regulating TRPM2. We conclude that PARP-1/PARG control a cell death signal pathway that operates between five different cell compartments and communicates via three types of chemical messengers: a nucleotide, a cation, and proteins.
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Giansanti V, Donà F, Tillhon M, Scovassi AI. PARP inhibitors: new tools to protect from inflammation. Biochem Pharmacol 2010; 80:1869-77. [PMID: 20417190 DOI: 10.1016/j.bcp.2010.04.022] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 04/12/2010] [Accepted: 04/13/2010] [Indexed: 10/19/2022]
Abstract
Poly(ADP-ribosylation) consists in the conversion of β-NAD(+) into ADP-ribose, which is then bound to acceptor proteins and further used to form polymers of variable length and structure. The correct turnover of poly(ADP-ribose) is ensured by the concerted action of poly(ADP-ribose) polymerase (PARP) and poly(ADP-ribose) glycohydrolase (PARG) enzymes, which are responsible for polymer synthesis and degradation, respectively. Despite the positive role of poly(ADP-ribosylation) in sensing and repairing DNA damage, generated also by ROS, PARP over-activation could allow NAD depletion and consequent necrosis, thus leading to an inflammatory condition in many diseases. In this respect, inhibition of PARP enzymes could exert a protective role towards a number of pathological conditions; i.e. the combined treatment of tumors with PARP inhibitors/anticancer agents proved to have a beneficial effect in cancer therapy. Thus, pharmacological inactivation of poly(ADP-ribosylation) could represent a novel therapeutic strategy to limit cellular injury and to attenuate the inflammatory processes that characterize many disorders.
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Affiliation(s)
- Vincenzo Giansanti
- Istituto di Genetica Molecolare CNR, Via Abbiategrasso 207, I-27100 Pavia, Italy
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Fauzee NJS, Pan J, Wang YL. PARP and PARG inhibitors--new therapeutic targets in cancer treatment. Pathol Oncol Res 2010; 16:469-78. [PMID: 20383759 DOI: 10.1007/s12253-010-9266-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 03/29/2010] [Indexed: 02/06/2023]
Abstract
Today, the number of cancer patients throughout the world is increasing alarmingly and as per the World Health Organisation (WHO) data and statistics the prediction for the year 2020 will be 15 million new cases as compared to only 10 million cases in year 2000 leaving us dumbfounded. A lot of effort has been put in by researchers and scientists over decades to find drugs helpful in the treatment of cancers for the benefit of patients--the latest being the Poly ADP-ribose polymerase (PARP) and the Poly ADP-ribose glycohydrolase (PARG) inhibitors. This review highlights their mechanism of action under the rationale of their use and current development in the field of cancer.
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Affiliation(s)
- Nilufer Jasmine Selimah Fauzee
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, China
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Formentini L, Macchiarulo A, Cipriani G, Camaioni E, Rapizzi E, Pellicciari R, Moroni F, Chiarugi A. Poly(ADP-ribose) catabolism triggers AMP-dependent mitochondrial energy failure. J Biol Chem 2009; 284:17668-76. [PMID: 19411252 PMCID: PMC2719406 DOI: 10.1074/jbc.m109.002931] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 04/24/2009] [Indexed: 11/06/2022] Open
Abstract
Upon massive DNA damage, hyperactivation of the nuclear enzyme poly(ADP-ribose) polymerase (PARP)-1 causes severe depletion of intracellular NAD and ATP pools as well as mitochondrial dysfunction. Thus far, the molecular mechanisms contributing to PARP-1-dependent impairment of mitochondrial functioning have not been identified. We found that degradation of the PARP-1 product poly(ADP-ribose) through the concerted actions of poly(ADP-ribose) glycohydrolase and NUDIX (nucleoside diphosphate-X) hydrolases leads to accumulation of AMP. The latter, in turn, inhibits the ADP/ATP translocator, prompting mitochondrial energy failure. For the first time, our findings identify NUDIX hydrolases as key enzymes involved in energy derangement during PARP-1 hyperactivity. Also, these data disclose unanticipated AMP-dependent impairment of mitochondrial exchange of adenine nucleotides, which can be of relevance to organelle functioning and disease pathogenesis.
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Affiliation(s)
- Laura Formentini
- From the Department of Preclinical and Clinical Pharmacology, University of Florence, 50139 Firenze
| | - Antonio Macchiarulo
- the Department of Medicinal Chemistry and Drug Technology, University of Perugia, 06100 Perugia, and
| | - Giulia Cipriani
- From the Department of Preclinical and Clinical Pharmacology, University of Florence, 50139 Firenze
| | - Emidio Camaioni
- the Department of Medicinal Chemistry and Drug Technology, University of Perugia, 06100 Perugia, and
| | - Elena Rapizzi
- the Department of Biochemical Sciences, University of Florence, 50139 Firenze, Italy
| | - Roberto Pellicciari
- the Department of Medicinal Chemistry and Drug Technology, University of Perugia, 06100 Perugia, and
| | - Flavio Moroni
- From the Department of Preclinical and Clinical Pharmacology, University of Florence, 50139 Firenze
| | - Alberto Chiarugi
- From the Department of Preclinical and Clinical Pharmacology, University of Florence, 50139 Firenze
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A specific isoform of poly(ADP-ribose) glycohydrolase is targeted to the mitochondrial matrix by a N-terminal mitochondrial targeting sequence. Exp Cell Res 2009; 315:3477-85. [PMID: 19389396 DOI: 10.1016/j.yexcr.2009.04.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 03/30/2009] [Accepted: 04/07/2009] [Indexed: 01/24/2023]
Abstract
Poly(ADP-ribose) polymerases (PARPs) convert NAD to polymers of ADP-ribose that are converted to free ADP-ribose by poly(ADP-ribose) glycohydrolase (PARG). The activation of the nuclear enzyme PARP-1 following genotoxic stress has been linked to release of apoptosis inducing factor from the mitochondria, but the mechanisms by which signals are transmitted between nuclear and mitochondrial compartments are not well understood. The study reported here has examined the relationship between PARG and mitochondria in HeLa cells. Endogenous PARG associated with the mitochondrial fraction migrated in the range of 60 kDa. Transient transfection of cells with PARG expression constructs with amino acids encoded by exon 4 at the N-terminus was targeted to the mitochondria as demonstrated by subcellular fractionation and immunofluorescence microscopy of whole cells. Deletion and missense mutants allowed identification of a canonical N-terminal mitochondrial targeting sequence consisting of the first 16 amino acids encoded by PARG exon 4. Sub-mitochondrial localization experiments indicate that this mitochondrial PARG isoform is targeted to the mitochondrial matrix. The identification of a PARG isoform as a component of the mitochondrial matrix raises several interesting possibilities concerning mechanisms of nuclear-mitochondrial cross talk involved in regulation of cell death pathways.
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32
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Burns DM, Ying W, Kauppinen TM, Zhu K, Swanson RA. Selective down-regulation of nuclear poly(ADP-ribose) glycohydrolase. PLoS One 2009; 4:e4896. [PMID: 19319190 PMCID: PMC2655720 DOI: 10.1371/journal.pone.0004896] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 02/18/2009] [Indexed: 11/18/2022] Open
Abstract
Background The formation of ADP-ribose polymers on target proteins by poly(ADP-ribose) polymerases serves a variety of cell signaling functions. In addition, extensive activation of poly(ADP-ribose) polymerase-1 (PARP-1) is a dominant cause of cell death in ischemia-reperfusion, trauma, and other conditions. Poly(ADP-ribose) glycohydrolase (PARG) degrades the ADP-ribose polymers formed on acceptor proteins by PARP-1 and other PARP family members. PARG exists as multiple isoforms with differing subcellular localizations, but the functional significance of these isoforms is uncertain. Methods / Principal Findings Primary mouse astrocytes were treated with an antisense phosphorodiamidate morpholino oligonucleotide (PMO) targeted to exon 1 of full-length PARG to suppress expression of this nuclear-specific PARG isoform. The antisense-treated cells showed down-regulation of both nuclear PARG immunoreactivity and nuclear PARG enzymatic activity, without significant alteration in cytoplasmic PARG activity. When treated with the genotoxic agent MNNG to induced PARP-1 activation, the antisense-treated cells showed a delayed rate of nuclear PAR degradation, reduced nuclear condensation, and reduced cell death. Conclusions/Significance These results support a preferentially nuclear localization for full-length PARG, and suggest a key role for this isoform in the PARP-1 cell death pathway.
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Affiliation(s)
- David M. Burns
- Department of Neurology, University of California at San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Weihai Ying
- Department of Neurology, University of California at San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Tiina M. Kauppinen
- Department of Neurology, University of California at San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Keqing Zhu
- Department of Neurology, University of California at San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Raymond A. Swanson
- Department of Neurology, University of California at San Francisco and Veterans Affairs Medical Center, San Francisco, California, United States of America
- * E-mail:
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Detection and pharmacological modulation of nicotinamide mononucleotide (NMN) in vitro and in vivo. Biochem Pharmacol 2009; 77:1612-20. [PMID: 19426698 DOI: 10.1016/j.bcp.2009.02.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 02/18/2009] [Accepted: 02/19/2009] [Indexed: 11/22/2022]
Abstract
The emerging key role of NAD-consuming enzymes in cell biology has renewed the interest in NAD resynthesis through the rescue pathways. The first step of the nicotinamide-dependent NAD-rescue pathway is operated by nicotinamide phosphoribosyl transferase (NaPRT) forming nicotinamide mononucleotide (NMN). Because of the difficulties in measuring NMN, numerous open questions exist about the pathophysiological relevance of NaPRT and NMN itself. Here, we describe a new method of fluorimetric NMN detection upon derivatization of its alkylpyridinium group with acetophenone. By adopting this method, we analyzed the kinetics of nicotinamide-dependent NAD recycling in HeLa and U937 cells. Measurement of NMN contents in subcellular fractions revealed that the nucleotide is highly enriched in mitochondria, suggesting intramitochondrial NAD synthesis. NMN increases in cells undergoing hyperactivation of the NAD-consuming enzyme poly(ADP-ribose) polymerase (PARP)-1, or exposed to gallotannin, a putative inhibitor of NMN-adenylyl transferases. Evidence that the inhibitor of NAD resynthesis FK866 selectively inhibits NaPRT having no effect on NMNAT activity is also provided. Importantly, NMN reduces NAD and ATP depletion in cells undergoing PARP-1 hyperactivation, significantly delaying cell death. Finally, we show that a single injection of FK866 in the mouse induces long-lasting (up to 16 h) but mild (approximately 20%) reduction of NMN contents in different organs, suggesting slow rate of basal NAD consumption in vivo. Data provide new information on the biochemistry and pharmacology of NAD biosynthesis, allowing a better understanding of pyridine nucleotide metabolism.
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