1
|
Living with the enemy: from protein-misfolding pathologies we know, to those we want to know. Ageing Res Rev 2021; 70:101391. [PMID: 34119687 DOI: 10.1016/j.arr.2021.101391] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/19/2021] [Accepted: 06/09/2021] [Indexed: 12/12/2022]
Abstract
Conformational diseases are caused by the aggregation of misfolded proteins. The risk for such pathologies develops years before clinical symptoms appear, and is higher in people with alpha-1 antitrypsin (AAT) polymorphisms. Thousands of people with alpha-1 antitrypsin deficiency (AATD) are underdiagnosed. Enemy-aggregating proteins may reside in these underdiagnosed AATD patients for many years before a pathology for AATD fully develops. In this perspective review, we hypothesize that the AAT protein could exert a new and previously unconsidered biological effect as an endogenous metal ion chelator that plays a significant role in essential metal ion homeostasis. In this respect, AAT polymorphism may cause an imbalance of metal ions, which could be correlated with the aggregation of amylin, tau, amyloid beta, and alpha synuclein proteins in type 2 diabetes mellitus (T2DM), Alzheimer's and Parkinson's diseases, respectively.
Collapse
|
2
|
Huang YF, Kuo MT, Liu YS, Cheng YM, Wu PY, Chou CY. A Dose Escalation Study of Trientine Plus Carboplatin and Pegylated Liposomal Doxorubicin in Women With a First Relapse of Epithelial Ovarian, Tubal, and Peritoneal Cancer Within 12 Months After Platinum-Based Chemotherapy. Front Oncol 2019; 9:437. [PMID: 31179244 PMCID: PMC6544081 DOI: 10.3389/fonc.2019.00437] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 05/07/2019] [Indexed: 12/23/2022] Open
Abstract
Background: Epithelial ovarian cancer (EOC) is the leading cause of gynecological cancer-related deaths worldwide. Preclinical studies found that copper-lowering agents could re-sensitize platinum-resistant cancer cells by enhancing the human copper transporter 1 (hCtr1)-mediated uptake of platinum. In the clinic, re-sensitization of platinum-resistance in relapsed EOC has been discovered by the application of trientine plus platinum (NCT01178112). However, no pharmacokinetic data of trientine has been reported in cancer patients. Purpose: Our study aimed to explore the safety and activity of trientine combined with carboplatin and pegylated liposomal doxorubicin (PLD) in patients with EOC, tubal, and peritoneal cancer who experienced disease progression during platinum-based chemotherapy or showed relapse <12 months after completing first-line chemotherapy. Also, we aimed to demonstrate pharmacokinetic parameters and to discover potential biomarkers in our EOC patients. Methods: In this dose escalation study, 18 Asian patients in six dosing cohorts received fixed doses of carboplatin (AUC 4) and PLD (LipoDox®, TTY Biopharm Co. Ltd., Taipei, Taiwan) (40 mg/m2, day 1 per 4-week cycle), and escalated daily trientine doses (range: 300–1800 mg; initiated 7 days before the 1st combination cycle) according to a 3 + 3 design. Results: No dose-limiting toxicity or treatment-related death was observed. Four patients (22.2%) developed grade 3 drug-related adverse events (AEs), whereas no grade 4 AEs were encountered. Anemia and grade 2 dizziness were the most common hematological toxicity and neurotoxicity, respectively. In a pharmacokinetics comparison with healthy volunteers in the literature, our patients achieved greater absorption after oral trientinem, and more rapid elimination of triethylenetetramine dihydrochloride at high doses. The clinical benefit rate was 33.3 and 50.0% in the platinum-resistant and the partially platinum-sensitive group, respectively. A high baseline serum iron level and low serum copper level might help differentiate subgroups of patients with different clinical responses. Nevertheless, no associations of the clinical response with the levels of serum hCtr1, ceruloplasmin, or copper were observed. Conclusion: Combination therapy with carboplatin, trientine, and PLD was well-tolerated and safe. Our results encourage the development of a future phase II trial. Clinical trial registration:ClinicalTrials.gov # NCT03480750.
Collapse
Affiliation(s)
- Yu-Fang Huang
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Macus Tien Kuo
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Yi-Sheng Liu
- Department of Medical Imaging, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Ya-Min Cheng
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Pei-Ying Wu
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Cheng-Yang Chou
- Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| |
Collapse
|
3
|
Fu C, Lizhao J, Luo Z, Wang T, Grapperhaus CA, Ding X, Kang YJ. Active uptake of hydrophilic copper complex Cu(ii)-TETA in primary cultures of neonatal rat cardiomyocytes. Metallomics 2019; 11:565-575. [PMID: 30761393 DOI: 10.1039/c8mt00277k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Myocardial ischemia leads to copper efflux from the heart. The ischemic tissue with a low copper content fails to take up copper from the circulation even under the conditions of serum copper elevation. Cardiac copper repletion thus requires other available forms of this element than those currently known to bind to copper transport proteins. The copper complex of triethylenetetramine (TETA) is a metabolite of TETA, which has the potential to increase cardiac copper content in vivo. In the present study, we synthesized Cu(ii)-TETA, analyzed its crystal structure, and demonstrated the role of this compound in facilitating copper accumulation in primary cultures of neonatal rat cardiomyocytes. The Cu(ii)-TETA compound formed a square pyramidal chloride salt [Cu(TETA)Cl]Cl structure, which dissociates from chloride in aqueous solution to yield the four-coordinate dication Cu(ii)-TETA. Cu(ii)-TETA was accumulated as an intact compound in cardiomyocytes. Analysis from time-dependent copper accumulation in cardiomyocytes defined a different dynamic process in copper uptake between Cu(ii)-TETA and CuCl2 exposure. An additive copper accumulation in cardiomyocytes was found when the cells were exposed to both CuCl2 and Cu(ii)-TETA. Gene silencing of copper transport 1 (CTR1) did not affect cross-membrane transportation of Cu(ii)-TETA, but inhibited copper cellular accumulation from CuCl2. Furthermore, the uptake of Cu(ii)-TETA by cardiomyocytes was ATP-dependent. It is thus concluded that the formation of Cu(ii)-TETA facilitates copper accumulation in cardiomyocytes through an active CTR1-independent transportation process.
Collapse
Affiliation(s)
- Chunyan Fu
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | | | | | | | | | | | | |
Collapse
|
4
|
Liu J, Chen C, Liu Y, Sun X, Ding X, Qiu L, Han P, James Kang Y. Trientine selectively delivers copper to the heart and suppresses pressure overload-induced cardiac hypertrophy in rats. Exp Biol Med (Maywood) 2018; 243:1141-1152. [PMID: 30472883 DOI: 10.1177/1535370218813988] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Dietary copper supplementation reverses pressure overload-induced cardiac hypertrophy by copper replenishment in the heart. A copper-selective chelator, trientine (triethylenetetramine [TETA]), reverses left ventricular hypertrophy associated with diabetes also by copper replenishment in the heart. The present study was undertaken to address the critical issue how TETA delivers copper to the heart. Adult male Sprague-Dawley rats were subjected to transverse aortic constriction (TAC) to induce cardiac hypertrophy. Eight weeks after the TAC surgery, cardiac hypertrophy was developed and copper content in the heart was reduced. TETA was then administrated by gavage in two different dosages (21.9 or 87.6 mg/kg day) for six weeks. The results showed that in the lower dosage, TETA replenished copper contents in the heart, along with a decrease in the copper concentration in the blood and kidney, and an increase in the urine. In the higher dosage, TETA did not replenish copper contents in the heart, but markedly increased copper concentrations in the urine and decreased those in the blood and kidney. Neither lower nor higher TETA dosage altered copper concentrations in other organs. Corresponding to myocardial copper replenishment, the lower dose TETA suppresses cardiac hypertrophy, as judged by a reduction in the left ventricle wall thickness and a decrease in the heart size, and diminished cardiac fibrosis, as reflected by a decrease in collagen I content. TETA in the higher dose not only did not suppress cardiac hypertrophy, but also caused cardiac hypertrophy in sham-operated rats. TETA-mediated myocardial copper restoration is independent of copper transporter-1 or -2 but related to an energy-dependent transportation. This study demonstrates that low-dose TETA functions as a copper chaperone, selectively delivering copper to the copper-deprived heart through an active transportation; in higher doses, TETA simply retains its chelator function, removing copper from the body by urinary excretion. Impact statement Our study reveals that TETA, traditionally regarded as a copper chelator, in lower doses delivers copper selectively to the heart through a mechanism independent of copper transporter-1 or -2. Copper supplementation by a lower dose of TETA suppresses pressure overload-induced cardiac hypertrophy. Since ischemic heart disease and hypertrophic cardiomyopathy are accompanied by myocardial copper loss, this approach of using a lower dose of TETA to supplement copper to the heart would help treat the disease condition of patients with such cardiac events.
Collapse
Affiliation(s)
- Jiaming Liu
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Chen Chen
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yinjie Liu
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xiaorong Sun
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xueqin Ding
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Liying Qiu
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Pengfei Han
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Y James Kang
- Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Memphis Institute of Regenerative Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
5
|
Liu Y, Xiao Y, Liu J, Feng L, Kang YJ. Copper-induced reduction in myocardial fibrosis is associated with increased matrix metalloproteins in a rat model of cardiac hypertrophy. Metallomics 2018; 10:201-208. [PMID: 29302675 DOI: 10.1039/c7mt00165g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AAC induces Cu loss from the heart and depressed MMP-2 in combination with increased TIMPs, leading to increased collagen deposition. TETA replenishes Cu in the heart, increases MMP-2, and decreases TIMP-1 and -2, collectively resulting in reduction in cardiac fibrosis.
Collapse
Affiliation(s)
- Yinjie Liu
- Regenerative Medicine Research Center
- Sichuan University West China Hospital
- Chengdu
- China
| | - Ying Xiao
- Regenerative Medicine Research Center
- Sichuan University West China Hospital
- Chengdu
- China
| | - Jiaming Liu
- Regenerative Medicine Research Center
- Sichuan University West China Hospital
- Chengdu
- China
| | - Li Feng
- Regenerative Medicine Research Center
- Sichuan University West China Hospital
- Chengdu
- China
| | - Y. James Kang
- Regenerative Medicine Research Center
- Sichuan University West China Hospital
- Chengdu
- China
| |
Collapse
|
6
|
Triethylenetetramine modulates polyamine and energy metabolism and inhibits cancer cell proliferation. Biochem J 2016; 473:1433-41. [DOI: 10.1042/bcj20160134] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 03/21/2016] [Indexed: 11/17/2022]
Abstract
Copper chelators show anticancer effects by preventing neo-angiogenesis. In the present study, we show that triethylenetetramine (TETA) is a multi-targeting drug, which modulates several key regulatory proteins of polyamine metabolism that contributes to its anticancer effect.
Collapse
|
7
|
Zhang S, Liu H, Amarsingh GV, Cheung CCH, Hogl S, Narayanan U, Zhang L, McHarg S, Xu J, Gong D, Kennedy J, Barry B, Choong YS, Phillips ARJ, Cooper GJS. Diabetic cardiomyopathy is associated with defective myocellular copper regulation and both defects are rectified by divalent copper chelation. Cardiovasc Diabetol 2014; 13:100. [PMID: 24927960 PMCID: PMC4070334 DOI: 10.1186/1475-2840-13-100] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 05/27/2014] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Heart disease is the leading cause of death in diabetic patients, and defective copper metabolism may play important roles in the pathogenesis of diabetic cardiomyopathy (DCM). The present study sought to determine how myocardial copper status and key copper-proteins might become impaired by diabetes, and how they respond to treatment with the Cu (II)-selective chelator triethylenetetramine (TETA) in DCM. METHODS Experiments were performed in Wistar rats with streptozotocin (STZ)-induced diabetes with or without TETA treatment. Cardiac function was analyzed in isolated-perfused working hearts, and myocardial total copper content measured by particle-induced x-ray emission spectroscopy (PIXE) coupled with Rutherford backscattering spectrometry (RBS). Quantitative expression (mRNA and protein) and/or activity of key proteins that mediate LV-tissue-copper binding and transport, were analyzed by combined RT-qPCR, western blotting, immunofluorescence microscopy, and enzyme activity assays. Statistical analysis was performed using Student's t-tests or ANOVA and p-values of < 0.05 have been considered significant. RESULTS Left-ventricular (LV) copper levels and function were severely depressed in rats following 16-weeks' diabetes, but both were unexpectedly normalized 8-weeks after treatment with TETA was instituted. Localized myocardial copper deficiency was accompanied by decreased expression and increased polymerization of the copper-responsive transition-metal-binding metallothionein proteins (MT1/MT2), consistent with impaired anti-oxidant defences and elevated susceptibility to pro-oxidant stress. Levels of the high-affinity copper transporter-1 (CTR1) were depressed in diabetes, consistent with impaired membrane copper uptake, and were not modified by TETA which, contrastingly, renormalized myocardial copper and increased levels and cell-membrane localization of the low-affinity copper transporter-2 (CTR2). Diabetes also lowered indexes of intracellular (IC) copper delivery via the copper chaperone for superoxide dismutase (CCS) to its target cuproenzyme, superoxide dismutase-1 (SOD1): this pathway was rectified by TETA treatment, which normalized SOD1 activity with consequent bolstering of anti-oxidant defenses. Furthermore, diabetes depressed levels of additional intracellular copper-transporting proteins, including antioxidant-protein-1 (ATOX1) and copper-transporting-ATPase-2 (ATP7B), whereas TETA elevated copper-transporting-ATPase-1 (ATP7A). CONCLUSIONS Myocardial copper deficiency and defective cellular copper transport/trafficking are revealed as key molecular defects underlying LV impairment in diabetes, and TETA-mediated restoration of copper regulation provides a potential new class of therapeutic molecules for DCM.
Collapse
Affiliation(s)
- Shaoping Zhang
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Hong Liu
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Greeshma V Amarsingh
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Carlos C H Cheung
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Sebastian Hogl
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Umayal Narayanan
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Lin Zhang
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Selina McHarg
- Centre for Advanced Discovery and Experimental Therapeutics, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, and the Centre for Diabetes and Endocrinology, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9WL, UK
| | - Jingshu Xu
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Deming Gong
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - John Kennedy
- National Isotope Centre, GNS Science, Gracefield, Wellington, New Zealand
| | - Bernard Barry
- National Isotope Centre, GNS Science, Gracefield, Wellington, New Zealand
| | - Yee Soon Choong
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Anthony R J Phillips
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, Auckland, New Zealand
| | - Garth J S Cooper
- The School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, Auckland, New Zealand
- Centre for Advanced Discovery and Experimental Therapeutics, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, and the Centre for Diabetes and Endocrinology, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9WL, UK
- Department of Pharmacology, Medical Sciences Division, University of Oxford, Oxford, UK
| |
Collapse
|
8
|
Torosantucci R, Weinbuch D, Klem R, Jiskoot W. Triethylenetetramine prevents insulin aggregation and fragmentation during copper catalyzed oxidation. Eur J Pharm Biopharm 2013; 84:464-71. [DOI: 10.1016/j.ejpb.2013.01.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/18/2013] [Accepted: 01/21/2013] [Indexed: 12/22/2022]
|
9
|
Lu J, Pontré B, Pickup S, Choong SY, Li M, Xu H, Gamble GD, Phillips ARJ, Cowan BR, Young AA, Cooper GJS. Treatment with a copper-selective chelator causes substantive improvement in cardiac function of diabetic rats with left-ventricular impairment. Cardiovasc Diabetol 2013; 12:28. [PMID: 23368770 PMCID: PMC3602174 DOI: 10.1186/1475-2840-12-28] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 01/14/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Defective copper regulation is implicated as a causative mechanism of organ damage in diabetes. Treatment with trientine, a divalent-copper-selective chelator, improves arterial and renal structure/function in diabetes, wherein it also ameliorates left-ventricular (LV) hypertrophy. However, direct in vivo evidence that trientine can improve cardiac function in heart failure has hitherto been lacking. METHODS To determine whether trientine treatment could improve in vivo outcome, we measured cardiac function in groups of trientine-treated diabetic (TETA-DIA), non-drug-treated diabetic (DIA) and sham-treated control (SHAM) rats, by using in vivo high-field cardiac magnetic-resonance imaging (cMRI) and an ex vivo isolated-perfused working heart method. Forty age-matched animals underwent a cMRI scan after which 12 were randomized to the SHAM group and 28 underwent streptozotocin-injection; of these, 25 developed stable diabetes, and 12 were then randomized to receive no treatment for 16 weeks (DIA) and the other 13 to undergo 8-weeks' untreated diabetes followed by 8-weeks' drug treatment (TETA-DIA). Animals were studied again by cMRI at 8 and 16 weeks following disease induction, and finally by measurement of ex vivo cardiac function. RESULTS After eight weeks diabetes, rats (DIA/TETA-DIA) had developed significant impairment of LV function, as judged by impairment of ejection fraction (LVEF), cardiac output (CO), and LV mass (LVM)/body-mass (all P < 0.001), as well as other functional indexes. LVEF, CO (both P < 0.001) and the other indexes deteriorated further at 16 weeks in DIA, whereas trientine (TETA-DIA) improved cardiac function by elevating LVEF and CO (both P < 0.001), and also partially reversed the increase in LVM/body-mass (P < 0.05). In ex vivo hearts from DIA, the CO response to increasing preload pressure was deficient compared with SHAM (P < 0.001) whereas the preload-CO relationship was significantly improved in TETA-DIA animals (P < 0.001). CONCLUSIONS Trientine treatment significantly improved cardiac function in diabetic rats with substantive LV impairment. These results implicate impaired copper regulation in the pathogenesis of impaired cardiac function caused by diabetic cardiomyopathy, and support ongoing studies of trientine treatment in patients with heart failure.
Collapse
Affiliation(s)
- Jun Lu
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Nurchi VM, Crisponi G, Crespo-Alonso M, Lachowicz JI, Szewczuk Z, Cooper GJS. Complex formation equilibria of Cu(II) and Zn(II) with triethylenetetramine and its mono- and di-acetyl metabolites. Dalton Trans 2012. [PMID: 23202417 DOI: 10.1039/c2dt32252h] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triethylenetetramine (TETA) dihydrochloride, or trientine, is a therapeutic molecule that has long been used as a copper-chelating agent for the second-line treatment of patients with Wilson's disease. More recently, it has also been employed as an experimental therapeutic molecule in diabetes where it improves cardiac structure in patients with diabetic cardiomyopathy and left-ventricular hypertrophy. TETA is metabolized by acetylation, which leads to the formation of two main metabolites in humans and other mammals, monoacetyl-TETA (MAT) and diacetyl-TETA (DAT). These metabolites have been identified in the plasma and urine of healthy and diabetic subjects treated with TETA, and could themselves play a role in TETA-mediated copper chelation and restoration of physiological copper regulation in diabetes. In this regard, a potentiometric and spectrophotometric study of Cu(II)-complex formation equilibria of TETA, MAT and DAT is presented here, to provide a comprehensive evaluation of the stoichiometries of the complexes formed and of their relative stability constants. A potentiometric study has also been conducted on the corresponding Zn(II) complexes, to evaluate any possible interference with TETA-mediated Cu(II) binding by this second physiological transition-metal ion, which is present in similar concentrations in human plasma and which also binds to TETA. An ESI-MS study of these systems has both confirmed the complex formation mechanisms established from the potentiometric and spectrophotometric results, and in addition provided direct information on the stoichiometry of the complexes formed in solution. These data when taken together show that the 1 : 1 complexes formed with Cu(II) and Zn(II) have different degrees of protonation. The stability of the Cu(II) and Zn(II) complexes with the three ligands, evaluated by the parameters pCu and pZn, decreases with the introduction of the acetyl groups. Nevertheless the stability of Cu(II) complexes with MAT is sufficiently high to enable its participation in copper scavenging from the patient. A speciation study of the behavior of TETA and MAT with Cu(II) in the presence of Zn(II) at peri-physiological plasma concentrations is also presented. While Zn(II) did not hinder copper binding, the possibility is raised that prolonged TETA treatment could possibly alter the homeostatic regulation of this essential metal ion. The lack of reliable literature stability constants concerning the Cu(II) and Zn(II) interaction with the major transport proteins in plasma is also briefly considered.
Collapse
Affiliation(s)
- Valeria M Nurchi
- Dipartimento di Scienze Chimiche e Geologiche, Cittadella Universitaria, 09042 Monserrato-Cagliari, Italy.
| | | | | | | | | | | |
Collapse
|
11
|
Hyvönen MT, Weisell J, Khomutov AR, Alhonen L, Vepsäläinen J, Keinänen TA. Metabolism of Triethylenetetramine and 1,12-Diamino-3,6,9-Triazadodecane by the Spermidine/Spermine-N1-Acetyltransferase and Thialysine Acetyltransferase. Drug Metab Dispos 2012; 41:30-2. [DOI: 10.1124/dmd.112.047274] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
12
|
Cooper GJS. Therapeutic potential of copper chelation with triethylenetetramine in managing diabetes mellitus and Alzheimer's disease. Drugs 2011; 71:1281-320. [PMID: 21770477 DOI: 10.2165/11591370-000000000-00000] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This article reviews recent evidence, much of which has been generated by my group's research programme, which has identified for the first time a previously unknown copper-overload state that is central to the pathogenesis of diabetic organ damage. This state causes tissue damage in the blood vessels, heart, kidneys, retina and nerves through copper-mediated oxidative stress. This author now considers this copper-overload state to provide an important new target for therapeutic intervention, the objective of which is to prevent or reverse the diabetic complications. Triethylenetetramine (TETA) has recently been identified as the first in a new class of anti-diabetic molecules through the original work reviewed here, thus providing a new use for this molecule, which was previously approved by the US FDA in 1985 as a second-line treatment for Wilson's disease. TETA acts as a highly selective divalent copper (Cu(II)) chelator that prevents or reverses diabetic copper overload, thereby suppressing oxidative stress. TETA treatment of diabetic animals and patients has identified and quantified the interlinked defects in copper metabolism that characterize this systemic copper overload state. Copper overload in diabetes mellitus differs from that in Wilson's disease through differences in their respective causative molecular mechanisms, and resulting differences in tissue localization and behaviour of the excess copper. Elevated pathogenetic tissue binding of copper occurs in diabetes. It may well be mediated by advanced-glycation endproduct (AGE) modification of susceptible amino-acid residues in long-lived fibrous proteins, for example, connective tissue collagens in locations such as blood vessel walls. These AGE modifications can act as localized, fixed endogenous chelators that increase the chelatable-copper content of organs such as the heart and kidneys by binding excessive amounts of catalytically active Cu(II) in specific vascular beds, thereby focusing the related copper-mediated oxidative stress in susceptible tissues. In this review, summarized evidence from our clinical studies in healthy volunteers and diabetic patients with left-ventricular hypertrophy, and from nonclinical models of diabetic cardiac, arterial, renal and neural disease is used to construct descriptions of the mechanisms by which TETA treatment prevents injury and regenerates damaged organs. Our recent phase II proof-of-principle studies in patients with type 2 diabetes and in nonclinical models of diabetes have helped to define the pathogenetic defects in copper regulation, and have shown that they are reversible by TETA. The drug tightly binds and extracts excess systemic Cu(II) into the urine whilst neutralizing its catalytic activity, but does not cause systemic copper deficiency, even after prolonged use. Its physicochemical properties, which are pivotal for its safety and efficacy, clearly differentiate it from all other clinically available transition metal chelators, including D-penicillamine, ammonium tetrathiomolybdate and clioquinol. The studies reviewed here show that TETA treatment is generally effective in preventing or reversing diabetic organ damage, and support its ongoing development as a new medicine for diabetes. Trientine (TETA dihydrochloride) has been used since the mid-1980s as a second-line treatment for Wilson's disease, and our recent clinical studies have reinforced the impression that it is likely to be safe for long-term use in patients with diabetes and related metabolic disorders. There is substantive evidence to support the view that diabetes shares many pathogenetic mechanisms with Alzheimer's disease and vascular dementia. Indeed, the close epidemiological and molecular linkages between them point to Alzheimer's disease/vascular dementia as a further therapeutic target where experimental pharmacotherapy with TETA could well find further clinical application.
Collapse
Affiliation(s)
- Garth J S Cooper
- Centre for Advanced Discovery and Experimental Therapeutics, NIHR Manchester Biomedical Research Centre, Central Manchester University Hospitals NHS Foundation Trust, UK.
| |
Collapse
|
13
|
Cerrada-Gimenez M, Weisell J, Hyvönen MT, Park MH, Alhonen L, Vepsäläinen J, Keinänen TA. Complex N-acetylation of triethylenetetramine. Drug Metab Dispos 2011; 39:2242-9. [PMID: 21878558 DOI: 10.1124/dmd.111.041798] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Triethylenetetramine (TETA) is an efficient copper chelator that has versatile clinical potential. We have recently shown that spermidine/spermine-N(1)-acetyltransferase (SSAT1), the key polyamine catabolic enzyme, acetylates TETA in vitro. Here, we studied the metabolism of TETA in three different mouse lines: syngenic, SSAT1-overexpressing, and SSAT1-deficient (SSAT1-KO) mice. The mice were sacrificed at 1, 2, or 4 h after TETA injection (300 mg/kg i.p.). We found only N(1)-acetyltriethylenetetramine (N(1)AcTETA) and/or TETA in the liver, kidney, and plasma samples. As expected, SSAT1-overexpressing mice acetylated TETA at an accelerated rate compared with syngenic and SSAT1-KO mice. It is noteworthy that SSAT1-KO mice metabolized TETA as syngenic mice did, probably by thialysine acetyltransferase, which had a K(m) value of 2.5 ± 0.3 mM and a k(cat) value of 1.3 s(-1) for TETA when tested in vitro with the human recombinant enzyme. Thus, the present results suggest that there are at least two N-acetylases potentially metabolizing TETA. However, their physiological significance for TETA acetylation requires further studies. Furthermore, we detected chemical intramolecular N-acetyl migration from the N(1) to N(3) position of N(1)AcTETA and N(1),N(8)-diacetyltriethylenetetramine in an acidified high-performance liquid chromatography sample matrix. The complex metabolism of TETA together with the intramolecular N-acetyl migration may explain the huge individual variations in the acetylation rate of TETA reported earlier.
Collapse
Affiliation(s)
- Marc Cerrada-Gimenez
- Department of Medicine, Biocenter Kuopio, University of Eastern Finland, Kuopio, Finland
| | | | | | | | | | | | | |
Collapse
|
14
|
Abstract
Triethylenetetramine (TETA), a Cu(II)-selective chelator, is commonly used for the treatment of Wilson's disease. Recently, it has been shown that TETA can be used in the treatment of cancer because it possesses telomerase inhibiting and anti-angiogenesis properties. Although TETA has been used in the treatment of Wilson's disease for decades, a comprehensive review on TETA pharmacology does not exist. TETA is poorly absorbed with a bioavailability of 8 to 30%. It is widely distributed in tissues with relatively high concentrations measured in liver, heart, and kidney. It is mainly metabolized via acetylation, and two major acetylated metabolites exist in human serum and urine. It is mainly excreted in urine as the unchanged parent drug and two acetylated metabolites. It has a relatively short half-life (2 to 4 hours) in humans. The most recent discoveries in TETA pharmacology show that the major pharmacokinetic parameters are not associated with the acetylation phenotype of N-acetyltransferase 2, the traditionally regarded drug acetylation enzyme, and the TETA-metabolizing enzyme is actually spermidine/spermine acetyltransferase. This review also covers the current preclinical and clinical application of TETA. A much needed overview and up-to-date information on TETA pharmacology is provided for clinicians or cancer researchers who intend to embark on cancer clinical trials using TETA or its close structural analogs.
Collapse
Affiliation(s)
- Jun Lu
- School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, New Zealand.
| |
Collapse
|
15
|
Crisponi G, Nurchi VM, Fanni D, Gerosa C, Nemolato S, Faa G. Copper-related diseases: From chemistry to molecular pathology. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2009.12.018] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
16
|
Lu J, Poppitt SD, Othman AA, Sunderland T, Ruggiero K, Willett MS, Diamond LE, Garcia WD, Roesch BG, Cooper GJS. Pharmacokinetics, pharmacodynamics, and metabolism of triethylenetetramine in healthy human participants: an open-label trial. J Clin Pharmacol 2010; 50:647-58. [PMID: 20145262 DOI: 10.1177/0091270009349379] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The selective Cu(II)-chelator, triethylenetetramine (TETA), is undergoing clinical trials for the treatment of heart failure in patients with diabetes. Recently, the authors showed that 2 acetylated metabolites, N(1)-acetyltriethylenetetramine (MAT) and N(1),N(10)-diacetyltriethylenetetramine (DAT), are formed in humans following oral TETA administration. Thus, it became necessary to determine whether the N-acetyltransferase (NAT) 2 phenotype has any effects on the pharmacological properties and safety profile of TETA. Twelve fast and 12 slow NAT2-phenotype healthy participants were recruited. After oral drug administration, the authors collected plasma and urine samples, measured plasma concentrations of TETA and its 2 metabolites along with concomitant urinary copper concentrations, and performed safety tests. They present, for the first time, the complete 24-hour pharmacokinetic profiles of TETA, MAT, and DAT in humans. There was no evidence for clear-cut differences in pharmacokinetic profiles between fast and slow acetylators. Pharmacodynamic analysis showed no significant differences in cupruresis between the 2 NAT2 phenotypes. Safety results were consistent with TETA being well tolerated, and no significant differences in safety profiles were observed between the 2 phenotypes. Based on these data, NAT2 phenotype does not affect TETA's pharmacokinetic, pharmacodynamic, or safety profiles. TETA may be acetylated via an alternative mechanism, such as that catalyzed by spermidine/spermine N(1)-acetyltranferase.
Collapse
Affiliation(s)
- Jun Lu
- School of Biological Sciences, Faculty of Science, University of Auckland, Auckland 1142, New Zealand
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Novel isosteric charge-deficient spermine analogue--1,12-diamino-3,6,9-triazadodecane: synthesis, pK(a) measurement and biological activity. Amino Acids 2009; 38:501-7. [PMID: 19953281 DOI: 10.1007/s00726-009-0409-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 10/20/2009] [Indexed: 12/30/2022]
Abstract
Ionic interactions are essential for the biological functions of the polyamines spermidine and spermine in mammalian physiology. Here, we describe a simple gram scale method to prepare 1,12-diamino-3,6,9-triazadodecane (SpmTrien), an isosteric charge-deficient spermine analogue. The protonation sites of SpmTrien were determined at pH range of 2.2-11.0 using two-dimensional (1)H-(15)N NMR spectroscopy, which proved to be more feasible than conventional methods. The macroscopic pK(a) values of SpmTrien (3.3, 6.3, 8.5, 9.5 and 10.3) are significantly lower than those of 1,12-diamino-4,9-diazadodecane (spermine). The effects of SpmTrien and its parent molecule, 1,8-diamino-3,6-diazaoctane (Trien), on cell growth and polyamine metabolism were investigated in DU145 prostate carcinoma cells. SpmTrien downregulated the biosynthetic enzymes ornithine decarboxylase (ODC) and S-adenosyl-L: -methionine decarboxylase and decreased intracellular polyamine levels, whereas the effects of Trien alone were minor. Interestingly, both SpmTrien and Trien were able to partially overcome growth arrest induced by an ODC inhibitor, alpha-difluoromethylornithine, indicating that they are able to mimic some functions of the natural polyamines. Thus, SpmTrien is a novel tool to influence polyamine interaction sites at the molecular level and offers a new means to study the contribution of the protonation of spermine amino group(s) in the regulation of polyamine-dependent biological processes.
Collapse
|
18
|
Cho HY, Blum RA, Sunderland T, Cooper GJS, Jusko WJ. Pharmacokinetic and pharmacodynamic modeling of a copper-selective chelator (TETA) in healthy adults. J Clin Pharmacol 2009; 49:916-28. [PMID: 19602718 DOI: 10.1177/0091270009337939] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The population pharmacokinetics (PK) and pharmacodynamics (PD) of triethylenetetramine (TETA) dihydrochloride (trientine, GC811007) administered orally as 100-, 300-, 600-, or 1800-mg twice-daily doses were assessed in healthy adult male and female volunteers. This study was a randomized, double-blind, placebo-controlled, group-sequential, dose-escalating design. Forty participants, 10 per dose level (8 receiving TETA, 2 receiving placebo), received twice-daily doses for 14 consecutive days. A 2-compartment model for the PK and a linear direct effect model for drug-induced copper excretion (PD) were employed. The population PK/PD model was applied using the NONMEM software. Covariates tested were glomerular filtration rate (GFR), body weight, and gender. Multiple daily doses of TETA were safe and generally well tolerated. The linear 2-compartment model with first-order absorption well characterized the serum concentration data. Although its role was small, GFR had a statistically significant (P < .05) influence on systemic clearance (CL/F). The augmentation of copper excretion was well described by a direct linear model in which the slope was related to GFR and gender (P < .001). The intersubject coefficient of variation was 22.2% for slope (SL) and 82.5% for intercept (ER0). TETA has consistent single/multiple-dose pharmacokinetics and dose-proportional and serum concentration-proportional effects on enhancing copper excretion.
Collapse
Affiliation(s)
- Hea-Young Cho
- 565 Hochstetter Hall, Department of Pharmaceutical Sciences, State University of New York at Buffalo, Buffalo, NY 14260, USA
| | | | | | | | | |
Collapse
|
19
|
The metal chelators, trientine and citrate, inhibit the development of cardiac pathology in the Zucker diabetic rat. EXPERIMENTAL DIABETES RESEARCH 2009; 2009:696378. [PMID: 19390595 PMCID: PMC2669293 DOI: 10.1155/2009/696378] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 01/26/2009] [Accepted: 02/17/2009] [Indexed: 01/04/2023]
Abstract
PURPOSE The objective of this study was to determine the efficacy of dietary supplementation with the metal chelators, trientine or citric acid, in preventing the development of cardiomyopathy in the Zucker diabetic rat. HYPOTHESIS We hypothesized that dietary chelators would attenuate metal-catalyzed oxidative stress and damage in tissues and protect against pathological changes in ventricular structure and function in type II diabetes. METHODS Animals (10 weeks old) included lean control (LC, fa/+), untreated Zucker diabetic fatty (ZDF, fa/fa), and ZDF rats treated with either trientine (triethylenetetramine) or citrate at 20 mg/d in drinking water, starting when rats were frankly diabetic. Cardiac functional assessment was determined using a Millar pressure/volume catheter placed in the left ventricle at 32 weeks of age. RESULTS End diastolic volume for the ZDF animals increased by 36% indicating LV dilatation (P < .05) and was accompanied by a 30% increase in the end diastolic pressure (P <or= .05). Both trientine and citric acid prevented the increases in EDV and EDP (P < .05). Ejection fraction and myocardial relaxation were also significantly improved with chelator treatment. CONCLUSION Dietary supplementation with trientine and citric acid significantly prevented structural and functional changes in the diabetic heart, supporting the merits of mild chelators for prevention of cardiovascular disease in diabetes.
Collapse
|
20
|
Masad A, Hayes L, Tabner BJ, Turnbull S, Cooper LJ, Fullwood NJ, German MJ, Kametani F, El-Agnaf OMA, Allsop D. Copper-mediated formation of hydrogen peroxide from the amylin peptide: a novel mechanism for degeneration of islet cells in type-2 diabetes mellitus? FEBS Lett 2007; 581:3489-93. [PMID: 17617411 DOI: 10.1016/j.febslet.2007.06.061] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 06/24/2007] [Indexed: 10/23/2022]
Abstract
Amyloid deposits derived from the amylin peptide accumulate within pancreatic islet beta-cells in most cases of type-2 diabetes mellitus (T2Dm). Human amylin 'oligomers' are toxic to these cells. Using two different experimental techniques, we found that H(2)O(2) was generated during the aggregation of human amylin into amyloid fibrils. This process was greatly stimulated by Cu(II) ions, and human amylin was retained on a copper affinity column. In contrast, rodent amylin, which is not toxic, failed to generate any H(2)O(2) and did not interact with copper. We conclude that the formation of H(2)O(2) from amylin could contribute to the progressive degeneration of islet cells in T2Dm.
Collapse
Affiliation(s)
- Atef Masad
- Biomedical Sciences Unit, Department of Biological Sciences, Lancaster University, Lancaster, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|