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Spottiswoode N, Haston JC, Hanners NW, Gruenberg K, Kim A, DeRisi JL, Wilson MR. Challenges and advances in the medical treatment of granulomatous amebic encephalitis. Ther Adv Infect Dis 2024; 11:20499361241228340. [PMID: 38312848 PMCID: PMC10838035 DOI: 10.1177/20499361241228340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 01/09/2024] [Indexed: 02/06/2024] Open
Abstract
Granulomatous amebic encephalitis, caused by the free-living amebae Balamuthia mandrillaris or Acanthamoeba species, is a rare and deadly infectious syndrome with a current mortality rate of >90%. Much work remains to define the optimal treatment for these infections. Here, we provide a comprehensive overview of the supporting evidence behind antimicrobials currently recommended by the Centers for Disease Control and Prevention (CDC) with updated statistics on survival rates and medication usage from the CDC Free-Living Ameba Database. We also discuss promising treatments, especially the emerging therapeutic agent nitroxoline, and provide recommendations for the next steps in this area.
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Affiliation(s)
- Natasha Spottiswoode
- Division of Infectious Diseases, University of California San Francisco, San Francisco, CA, USA
| | - Julia C. Haston
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Natasha W. Hanners
- Division of Pediatric Infectious Diseases, University of Texas Southwestern, Dallas, TX, USA
| | - Katherine Gruenberg
- Department of Clinical Pharmacy, University of California San Francisco School of Pharmacy, San Francisco, CA, USA
| | - Annie Kim
- Department of Clinical Pharmacy, Zuckerberg San Francisco General, San Francisco, CA, USA
| | - Joseph L. DeRisi
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Chan Zuckerberg Biohub SF, San Francisco, CA, USA
| | - Michael R. Wilson
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94143, USA
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Kangussu-Marcolino MM, Ehrenkaufer GM, Chen E, Debnath A, Singh U. Identification of plicamycin, TG02, panobinostat, lestaurtinib, and GDC-0084 as promising compounds for the treatment of central nervous system infections caused by the free-living amebae Naegleria, Acanthamoeba and Balamuthia. Int J Parasitol Drugs Drug Resist 2019; 11:80-94. [PMID: 31707263 PMCID: PMC6849155 DOI: 10.1016/j.ijpddr.2019.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/18/2019] [Accepted: 10/17/2019] [Indexed: 01/11/2023]
Abstract
The free-living amebae Naegleria, Acanthamoeba, and Balamuthia cause rare but life-threatening infections. All three parasites can cause meningoencephalitis. Acanthamoeba can also cause chronic keratitis and both Balamuthia and Acanthamoeba can cause skin and systemic infections. There are minimal drug development pipelines for these pathogens despite a lack of available treatment regimens and high fatality rates. To identify anti-amebic drugs, we screened 159 compounds from a high-value repurposed library against trophozoites of the three amebae. Our efforts identified 38 compounds with activity against at least one ameba. Multiple drugs that bind the ATP-binding pocket of mTOR and PI3K are active, highlighting these compounds as important inhibitors of these parasites. Importantly, 24 active compounds have progressed at least to phase II clinical studies and overall 15 compounds were active against all three amebae. Based on central nervous system (CNS) penetration or exceptional potency against one amebic species, we identified sixteen priority compounds for the treatment of meningoencephalitis caused by these pathogens. The top five compounds are (i) plicamycin, active against all three free-living amebae and previously U.S. Food and Drug Administration (FDA) approved, (ii) TG02, active against all three amebae, (iii and iv) FDA-approved panobinostat and FDA orphan drug lestaurtinib, both highly potent against Naegleria, and (v) GDC-0084, a CNS penetrant mTOR inhibitor, active against at least two of the three amebae. These results set the stage for further investigation of these clinically advanced compounds for treatment of infections caused by the free-living amebae, including treatment of the highly fatal meningoencephalitis.
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Affiliation(s)
- Monica M Kangussu-Marcolino
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Grant Building, S-143, 300 Pasteur Drive, Stanford, CA, 94305, USA
| | - Gretchen M Ehrenkaufer
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Grant Building, S-143, 300 Pasteur Drive, Stanford, CA, 94305, USA
| | - Emily Chen
- uHTS Laboratory Rm 101, 11119 N Torrey Pines Rd. Calibr, A Division of the Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Anjan Debnath
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Upinder Singh
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Grant Building, S-143, 300 Pasteur Drive, Stanford, CA, 94305, USA; Department of Microbiology and Immunology, Stanford University, Stanford, CA, 94305, USA.
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Tatematsu N, Waguri-Nagaya Y, Kawaguchi Y, Oguri Y, Ikuta K, Kobayashi M, Nozaki M, Asai K, Aoyama M, Otsuka T. Mithramycin has inhibitory effects on gliostatin and matrix metalloproteinase expression induced by gliostatin in rheumatoid fibroblast-like synoviocytes. Mod Rheumatol 2017; 28:495-505. [PMID: 28741989 DOI: 10.1080/14397595.2017.1350332] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
OBJECTIVES Gliostatin (GLS) has angiogenic and arthritogenic activities and enzymatic activity as thymidine phosphorylase. Aberrant GLS production has been observed in the synovial membranes of patients with rheumatoid arthritis (RA). Matrix metalloproteinases (MMPs) are involved in joint destruction. Promoters of GLS and some MMP genes contain Sp1 binding sites. We examined the inhibitory effect of the Sp1 inhibitor mithramycin on GLS-induced GLS and MMP expression in cultured fibroblast-like synoviocytes (FLSs). METHODS Synovial tissue samples were obtained from patients with RA. FLSs pretreated with mithramycin were cultured with GLS. The mRNA expression levels of GLS and MMP-1, MMP-2, MMP-3, MMP-9, and MMP-13 were determined using reverse transcription polymerase chain reactions. Protein levels were measured using enzyme immunoassay and gelatin zymography. RESULTS GLS upregulated the expression of GLS itself and of MMP-1, MMP-3, MMP-9, and MMP-13, an effect significantly reduced by treatment with mithramycin. GLS and mithramycin had no effect on MMP-2 expression. CONCLUSIONS Mithramycin downregulated the increased expression of GLS and MMP-1, MMP-3, MMP-9, and MMP-13 in FLSs treated with GLS. Because GLS plays a pathological role in RA, blocking GLS stimulation using an agent such as mithramycin may be a novel approach to antirheumatic therapy.
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Affiliation(s)
- Naoe Tatematsu
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Yuko Waguri-Nagaya
- b Department of Joint Surgery for Rheumatic Diseases , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Yohei Kawaguchi
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Yusuke Oguri
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Kenji Ikuta
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Masaaki Kobayashi
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Masahiro Nozaki
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Kiyofumi Asai
- c Department of Molecular Neurobiology , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
| | - Mineyoshi Aoyama
- d Department of Pathobiology , Nagoya City University Graduate School of Pharmaceutical Sciences , Nagoya , Japan
| | - Takanobu Otsuka
- a Department of Orthopaedic Surgery , Nagoya City University Graduate School of Medical Sciences , Nagoya , Japan
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Grohar PJ, Glod J, Peer CJ, Sissung TM, Arnaldez FI, Long L, Figg WD, Whitcomb P, Helman LJ, Widemann BC. A phase I/II trial and pharmacokinetic study of mithramycin in children and adults with refractory Ewing sarcoma and EWS-FLI1 fusion transcript. Cancer Chemother Pharmacol 2017; 80:645-652. [PMID: 28735378 DOI: 10.1007/s00280-017-3382-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 06/30/2017] [Indexed: 12/20/2022]
Abstract
PURPOSE In a preclinical drug screen, mithramycin was identified as a potent inhibitor of the Ewing sarcoma EWS-FLI1 transcription factor. We conducted a phase I/II trial to determine the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), and pharmacokinetics (PK) of mithramycin in children with refractory solid tumors, and the activity in children and adults with refractory Ewing sarcoma. PATIENTS AND METHODS Mithramycin was administered intravenously over 6 h once daily for 7 days for 28 day cycles. Adult patients (phase II) initially received mithramycin at the previously determined recommended dose of 25 µg/kg/dose. The planned starting dose for children (phase I) was 17.5 µg/kg/dose. Plasma samples were obtained for mithramycin PK analysis. RESULTS The first two adult patients experienced reversible grade 4 alanine aminotransferase (ALT)/aspartate aminotransferase (AST) elevation exceeding the MTD. Subsequent adult patients received mithramycin at 17.5 µg/kg/dose, and children at 13 µg/kg/dose with dexamethasone pretreatment. None of the four subsequent adult and two pediatric patients experienced cycle 1 DLT. No clinical responses were observed. The average maximal mithramycin plasma concentration in four patients was 17.8 ± 4.6 ng/mL. This is substantially below the sustained mithramycin concentrations ≥50 nmol/L required to suppress EWS-FLI1 transcriptional activity in preclinical studies. Due to inability to safely achieve the desired mithramycin exposure, the trial was closed to enrollment. CONCLUSIONS Hepatotoxicity precluded the administration of a mithramycin at a dose required to inhibit EWS-FLI1. Evaluation of mithramycin in patients selected for decreased susceptibility to elevated transaminases may allow for improved drug exposure.
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Affiliation(s)
- Patrick J Grohar
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
- Department of Pediatrics, Van Andel Research Institute, Helen DeVos Children's Hospital, Michigan State University, East Lansing, USA
| | - John Glod
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
| | - Cody J Peer
- Clinical Pharmacology Program, National Cancer Institute, Bethesda, MD, USA
| | - Tristan M Sissung
- Department of Pediatrics, Van Andel Research Institute, Helen DeVos Children's Hospital, Michigan State University, East Lansing, USA
| | - Fernanda I Arnaldez
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Lauren Long
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - William D Figg
- Clinical Pharmacology Program, National Cancer Institute, Bethesda, MD, USA
| | - Patricia Whitcomb
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Lee J Helman
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Brigitte C Widemann
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
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Roth J, Peer CJ, Widemann B, Cole DE, Ershler R, Helman L, Schrump D, Figg WD. Quantitative determination of mithramycin in human plasma by a novel, sensitive ultra-HPLC-MS/MS method for clinical pharmacokinetic application. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 970:95-101. [PMID: 25247492 PMCID: PMC4188709 DOI: 10.1016/j.jchromb.2014.08.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 08/15/2014] [Accepted: 08/17/2014] [Indexed: 12/17/2022]
Abstract
Mithramycin is a neoplastic antibiotic synthesized by various Streptomyces bacteria. It is under investigation as a chemotherapeutic treatment for a wide variety of cancers. Ongoing and forthcoming clinical trials will require pharmacokinetic analysis of mithramycin in humans, both to see if target concentrations are achieved and to optimize dosing and correlate outcomes (response/toxicity) with pharmacokinetics. Two published methods for mithramycin quantitation exist, but both are immunoassays that lack current bioanalytical standards of selectivity and sensitivity. To provide an upgraded and more widely applicable assay, a UPLC-MS/MS method for quantitation of mithramycin in human plasma was developed. Solid-phase extraction allowed for excellent recoveries (>90%) necessary for high throughput analyses on sensitive instrumentation. However, a ∼55% reduction in analyte signal was observed as a result of plasma matrix effects. Mithramycin and the internal standard chromomycin were separated on a Waters Acquity BEH C18 column (2.1×50 mm, 1.7 μm) and detected using electrospray ionization operated in the negative mode at mass transitions m/z 1083.5→268.9 and 1181.5→269.0, respectively, on an AB Sciex QTrap 5500. The assay range was 0.5-500 ng/mL and proved to be linear (r(2)>0.996), accurate (≤10% deviation), and precise (CV<15%). Mithramycin was stable in plasma at room temperature for 24 h, as well as through three freeze-thaw cycles. This method was subsequently used to quantitate mithramycin plasma concentrations from patients enrolled on two clinical trials at the NCI.
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Affiliation(s)
- Jeffrey Roth
- Clinical Pharmacology Program, National Cancer Institute, Bethesda, MD, United States
| | - Cody J Peer
- Clinical Pharmacology Program, National Cancer Institute, Bethesda, MD, United States
| | - Brigitte Widemann
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, United States
| | - Diane E Cole
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, United States
| | - Rachel Ershler
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, United States
| | - Lee Helman
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, United States
| | - David Schrump
- Thoracic Oncology Branch, National Cancer Institute, Bethesda, MD, United States
| | - William D Figg
- Clinical Pharmacology Program, National Cancer Institute, Bethesda, MD, United States.
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Ikuta K, Waguri-Nagaya Y, Kikuchi K, Yamagami T, Nozaki M, Aoyama M, Asai K, Otsuka T. The Sp1 transcription factor is essential for the expression of gliostatin/thymidine phosphorylase in rheumatoid fibroblast-like synoviocytes. Arthritis Res Ther 2012; 14:R87. [PMID: 22534375 PMCID: PMC3446461 DOI: 10.1186/ar3811] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 04/01/2012] [Accepted: 04/25/2012] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Gliostatin/thymidine phosphorylase (GLS/TP) has angiogenic and arthritogenic activities, and aberrant GLS production has been observed in the active synovial membranes of rheumatoid arthritis (RA) patients. The human GLS gene promoter contains at least seven consensus binding sites for the DNA binding protein Sp1. Here we examined whether Sp1 is necessary for GLS production in RA. We also studied the effects of the Sp1 inhibitor mithramycin on GLS production in RA fibroblast-like synoviocytes (FLSs). METHODS FLSs from RA patients were treated with specific inhibitors. The gene and protein expression of GLS were studied using the quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and an enzyme immunoassay. Intracellular signalling pathway activation was determined by western blotting analysis, a luciferase assay, a chromatin immunoprecipitation (ChIP) assay and a small interfering RNA (siRNA) transfection. RESULTS The luciferase and ChIP assays showed that Sp1 binding sites in the GLS promoter were essential for GLS messenger RNA (mRNA) expression. GLS production was suppressed in FLSs by siRNA against Sp1 transfection. Mithramycin decreased GLS promoter activity, mRNA and protein expression in FLSs. Tumour necrosis factor-α (TNF-α) significantly increased GLS expression in RA FLSs; this effect was reduced by pre-treatment with cycloheximide and mithramycin. CONCLUSIONS Pretreatment of mithramycin and Sp1 silencing resulted in a significant suppression of GLS production in TNF-α-stimulated FLSs compared to controls. GLS gene expression enhanced by TNF-α was partly mediated through Sp1. As physiological concentrations of mithramycin can regulate GLS production in RA, mithramycin is a promising candidate for anti-rheumatic therapy.
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Affiliation(s)
- Kenji Ikuta
- Department of Orthopedic Surgery, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, MuzuhoMizuho-ku, Nagoya, 467-8601, Japan
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Barceló F, Ortiz-Lombardía M, Martorell M, Oliver M, Méndez C, Salas JA, Portugal J. DNA binding characteristics of mithramycin and chromomycin analogues obtained by combinatorial biosynthesis. Biochemistry 2010; 49:10543-52. [PMID: 21067184 DOI: 10.1021/bi101398s] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The antitumor antibiotics mithramycin A and chromomycin A(3) bind reversibly to the minor groove of G/C-rich regions in DNA in the presence of dications such as Mg(2+), and their antiproliferative activity has been associated with their ability to block the binding of certain transcription factors to gene promoters. Despite their biological activity, their use as anticancer agents is limited by severe side effects. Therefore, in our pursuit of new structurally related molecules showing both lower toxicity and higher biological activity, we have examined the binding to DNA of six analogues that we have obtained by combinatorial biosynthetic procedures in the producing organisms. All these molecules bear a variety of changes in the side chain attached to C-3 of the chromophore. The spectroscopic characterization of their binding to DNA followed by the evaluation of binding parameters and associated thermodynamics revealed differences in their binding affinity. DNA binding was entropically driven, dominated by the hydrophobic transfer of every compound from solution into the minor groove of DNA. Among the analogues, mithramycin SDK and chromomycin SDK possessed the higher DNA binding affinities.
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Affiliation(s)
- Francisca Barceló
- Departament de Biologia Fundamental i Ciencies de la Salut, Universitat de les Illes Balears, Palma de Mallorca, Spain
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Fibach E, Bianchi N, Borgatti M, Prus E, Gambari R. Mithramycin induces fetal hemoglobin production in normal and thalassemic human erythroid precursor cells. Blood 2003; 102:1276-81. [PMID: 12738678 DOI: 10.1182/blood-2002-10-3096] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We report in this paper that the DNA-binding drug mithramycin is a potent inducer of gamma-globin mRNA accumulation and fetal hemoglobin (HbF) production in erythroid cells from healthy human subjects and beta-thalassemia patients. Erythroid precursors derived from peripheral blood were grown in 2-phase liquid culture. In this procedure, early erythroid progenitors proliferate and differentiate during phase 1 (in the absence of erythropoietin) into late progenitors. In phase 2, in the presence of erythropoietin, the latter cells continue their proliferation and mature into Hb-containing orthochromatic normoblasts. Compounds were added on days 4 to 5 of phase 2 (when cells started to synthesize Hb), and cells were harvested on day 12. Accumulation of mRNAs for gamma-globin, beta-globin, alpha-globin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and beta-actin were measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR); induction of HbF was analyzed by high-performance liquid chromatography (HPLC) and, at cellular level, by flow cytometry. We demonstrated that mithramycin was able to up-regulate preferentially gamma-globin mRNA production and to increase HbF accumulation, the percentage of HbF-containing cells, and their HbF content. Mithramycin was more effective than hydroxyurea, being, in addition, not cytotoxic. This was shown by the lack of cytotoxicity on erythroid and myeloid in vitro primary cell cultures treated with mithramycin at concentrations effective for HbF induction. These results are of potential clinical significance because an increase of HbF alleviates the symptoms underlying beta-thalassemia and sickle cell anemia. The results of this report suggest that mithramycin and its analogs warrant further evaluation as potential therapeutic drugs.
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Affiliation(s)
- Eitan Fibach
- Department of Hematology, Hadassah University Hospital, Jerusalem, Israel
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Fishbein I, Brauner R, Chorny M, Gao J, Chen X, Laks H, Golomb G. Local delivery of mithramycin restores vascular reactivity and inhibits neointimal formation in injured arteries and vascular grafts. J Control Release 2001; 77:167-81. [PMID: 11733085 DOI: 10.1016/s0168-3659(01)00472-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Arterial restenosis is responsible for the high failure rates of vascular reconstruction procedures. Local sustained drug delivery has shown promise in the prevention of restenosis. The drug release rate from mithramycin-loaded EVA matrices (0.1%) was evaluated, and their antirestenotic effect was studied in the rat carotid model and rabbit model of vascular grafts. The modulation of c-myc expression by mithramycin treatment was examined by immunohistochemistry in the rat carotid model. The proliferative response of injured rat arteries was studied by bromdeoxyuridine (BrdU) immunostaining. The impact of mithramycin treatment on vasomotor responses of the venous segments grafted into arterial circulation was studied ex vivo using vasoreactive compounds. Mithramycin was released exponentially from EVA matrices in PBS. Matrices co-formulated with PEG-4600 revealed enhanced release kinetics. The perivascular implantation of drug-loaded EVA-PEG matrices led to 50% reduction of neointimal formation, and reduced the c-myc expression and BrdU labeling in comparison to control implants. Decreased sensitivity of mithramycin-treated grafts to serotonin-induced vasoconstriction was observed. Local perivascular mithramycin treatment limits the functional alteration caused by the grafting of venous segments in high-pressure arterial environment, and potently inhibits stenosis secondary to grafting and angioplasty injury. The antirestenotic effect is associated with reduced c-myc expression and with subsequent decrease in SMC proliferation.
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Affiliation(s)
- I Fishbein
- Department of Pharmaceutics, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, POB 12065, 91120, Jerusalem, Israel
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