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Frazaei MH, Nouri R, Arefnezhad R, Pour PM, Naseri M, Assar S. A Review of Medicinal Plants and Phytochemicals for the Management of Gout. Curr Rheumatol Rev 2024; 20:223-240. [PMID: 37828678 DOI: 10.2174/0115733971268037230920072503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/08/2023] [Accepted: 08/10/2023] [Indexed: 10/14/2023]
Abstract
Gout, characterized by elevated uric acid levels, is a common inflammatory joint disease associated with pain, joint swelling, and bone erosion. Existing treatments for gout often result in undesirable side effects, highlighting the need for new, safe, and cost-effective anti-gout drugs. Natural products, including medicinal plants and phytochemicals, have gained attention as potential sources of anti-gout compounds. In this review, we examined articles from 2000 to 2020 using PubMed and Google Scholar, focusing on the effectiveness of medicinal plants and phyto-chemicals in managing gout. Our findings identified 14 plants and nine phytochemicals with anti-gout properties. Notably, Teucrium polium, Prunus avium, Smilax riparia, Rhus coriaria, Foenic-ulum vulgare, Allium cepa, Camellia japonica, and Helianthus annuus exhibited the highest xa-thine oxidase inhibitory activity, attributed to their unique natural bioactive compounds such as phenolics, tannins, coumarins, terpenoids, and alkaloids. Herbal plants and their phytochemicals have demonstrated promising effects in reducing serum urate and inhibiting xanthine. This review aims to report recent studies on plants/phytochemicals derived from herbs beneficial in gout and their different mechanisms.
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Affiliation(s)
- Mohammad Hosein Frazaei
- Department of Pharmacology, Medical Technology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Roghayeh Nouri
- Department of Pharmacology, Medical Technology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Reza Arefnezhad
- Anatomical Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Pardis Mohammadi Pour
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Naseri
- Department of Pharmacology, Medical Technology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Shirin Assar
- Clinical Research Development Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran
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2
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Azeez AM, Hadwan MH. Simple assay for quantifying xanthine oxidase activity. Anal Biochem 2023; 673:115192. [PMID: 37225068 DOI: 10.1016/j.ab.2023.115192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 05/13/2023] [Accepted: 05/20/2023] [Indexed: 05/26/2023]
Abstract
This paper reports a sensitive method for assaying xanthine oxidase (XO) enzyme activity. XO produces hydrogen peroxide (H2O2) and superoxide anion radicals (O2•-), promoting the development of oxidative stress-related diseases, and is inhibited by various plant extracts. XO activity is quantified by incubating enzyme samples with an appropriate xanthine concentration as the substrate. The proposed method requires XO activity to be quantified based on H2O2 generation using a 3,3',5,5'-tetramethylbenzidine (TMB)-H2O2 system catalyzed by cupric ions. After a 30-minute incubation at 37 °C, sufficient cupric ion and TMB amounts are added. The assay produces optical signals that can be visually recognized or detected with a UV-visible spectrometer. A direct correlation was found between XO activity and the absorbance at 450 nm of the resulting di-imine (dication) yellow product. The proposed method uses sodium azide to prevent catalase enzyme interference. The new assay's function was confirmed using the TMB-XO assay and a Bland-Altman plot. The resulting correlation coefficient was 0.9976. The innovative assay was relatively precise and comparable to the comparison protocols. In conclusion, the presented method is very efficient at measuring XO activity.
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Affiliation(s)
- Ahlam Majid Azeez
- Chemistry Dept., College of Science, University of Babylon, Iraq Hilla City, Babylon Governorate, p.o. 51002, Iraq.
| | - Mahmoud Hussain Hadwan
- Chemistry Dept., College of Science, University of Babylon, Iraq Hilla City, Babylon Governorate, p.o. 51002, Iraq.
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3
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Cicero AFG, Caliceti C, Fogacci F, Giovannini M, Calabria D, Colletti A, Veronesi M, Roda A, Borghi C. Effect of apple polyphenols on vascular oxidative stress and endothelium function: a translational study. Mol Nutr Food Res 2017; 61. [PMID: 28755406 DOI: 10.1002/mnfr.201700373] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 07/01/2017] [Accepted: 07/11/2017] [Indexed: 12/21/2022]
Abstract
SCOPE We aimed examining apple polyphenols' effect on uricemia and endothelial function in a sample of overweight subjects. METHODS AND RESULTS This was a two-phased study. In vitro experiment aimed to evaluate apple polyphenols' ability to lower uric acid in comparison with allopurinol. In vivo study consisted in a randomized, double-blind, parallel placebo-controlled clinical trial involving 62 overweight volunteers with suboptimal values of fasting plasma glucose (100 mg/dL≤FPG≤125 mg/dL), randomized to 300 mg apple polyphenols or placebo for 8 weeks. Apple polyphenols extract inhibited xanthine oxidase activity, with an IC50 = 130 ± 30 ng/mL; reducing uric acid production with an IC50 = 154 ± 28 ng/mL. During the trial, after the first 4 weeks of treatment, FPG decreased in the active treated group (-6.1%, p < 0.05), while no significant changes were observed regarding the other hematochemistry parameters. After 4 more weeks of treatment, active-treated patients had an improvement in FPG compared to baseline (-10.3%, p < 0,001) and the placebo group (p < 0,001). Uric acid (-14.0%, p < 0.05 versus baseline; p < 0.05 versus placebo) and endothelial reactivity (0.24±0.09, p = 0.009 versus baseline; p < 0.05 versus placebo) significantly improved too. CONCLUSION In vivo, apple polyphenols extract has a positive effect on vascular oxidative stress and endothelium function and reduce FPG and uric acid by inhibiting xanthine oxidase, as our In vitro experiment attests.
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Affiliation(s)
- Arrigo F G Cicero
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Cristiana Caliceti
- Department of Chemistry "Giacomo Ciamician", Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA) - Alma Mater Studiorum, University of Bologna, Bologna, Italy.,Istituto Nazionale Biostrutture e Biosistemi (INBB), Roma, Italy
| | - Federica Fogacci
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Marina Giovannini
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Donato Calabria
- Department of Chemistry "Giacomo Ciamician", Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA) - Alma Mater Studiorum, University of Bologna, Bologna, Italy.,Istituto Nazionale Biostrutture e Biosistemi (INBB), Roma, Italy
| | - Alessandro Colletti
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Maddalena Veronesi
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Aldo Roda
- Department of Chemistry "Giacomo Ciamician", Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA) - Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Claudio Borghi
- Atherosclerosis Research Unit, Medicine & Surgery Sciences Dept., Alma Mater Studiorum University of Bologna, Bologna, Italy
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4
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Caliceti C, Calabria D, Roda A. A new sensitive and quantitative chemiluminescent assay to monitor intracellular xanthine oxidase activity for rapid screening of inhibitors in living endothelial cells. Anal Bioanal Chem 2016; 408:8755-8760. [PMID: 27392750 DOI: 10.1007/s00216-016-9763-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/17/2016] [Accepted: 07/01/2016] [Indexed: 10/21/2022]
Abstract
Xanthine oxidase (XO) is an important enzyme, expressed at high levels in the vasculature in endothelial cells, that catalyzes the hydroxylation of hypoxanthine to xanthine and xanthine to uric acid. Excessive production of uric acid results in hyperuricemia linked to gout and cardiovascular diseases. Testing inhibition of XO is important for detection of potentially effective drugs or natural products that could be used to treat diseases caused by increased XO activity. In the present study, for the first time, we developed an in vitro chemiluminescent bioassay to determine XO activity in living endothelial cells and the IC50 value of oxypurinol, the active metabolite of the inhibitor drug allopurinol. Intracellular XO activity was measured in less than 20 min with a luminol/catalyst-based chemiluminescence assay able to measure XO with a limit of 0.4 μU/mL. Oxypurinol addition to 5 × 103 cells (ranging from 5.0 to 0.0 μM) caused a linear decrease in XO activity, with an IC50 of 1.0 ± 0.5 μM. The detection system developed was low-cost, rapid, reproducible, and easily miniaturizable so suitable to be used on small quantities of cells.
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Affiliation(s)
- C Caliceti
- Department of Chemistry "Giacomo Ciamician", Alma Mater Studiorum - University of Bologna, Bologna, Italy. .,Istituto Nazionale Biostrutture e Biosistemi (INBB), Rome, Italy. .,Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Alma Mater Studiorum - University of Bologna, Bologna, Italy.
| | - D Calabria
- Department of Chemistry "Giacomo Ciamician", Alma Mater Studiorum - University of Bologna, Bologna, Italy.,Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - A Roda
- Department of Chemistry "Giacomo Ciamician", Alma Mater Studiorum - University of Bologna, Bologna, Italy.,Istituto Nazionale Biostrutture e Biosistemi (INBB), Rome, Italy.,Centro Interdipartimentale di Ricerca Industriale Energia e Ambiente (CIRI EA), Alma Mater Studiorum - University of Bologna, Bologna, Italy
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5
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Vyas P, Kalidindi S, Chibrikova L, Igamberdiev AU, Weber JT. Chemical analysis and effect of blueberry and lingonberry fruits and leaves against glutamate-mediated excitotoxicity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:7769-76. [PMID: 23875756 DOI: 10.1021/jf401158a] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Phenolic compounds are a large class of phytochemicals that are widespread in the plant kingdom and known to have antioxidant capacities. This study aimed to determine the antioxidant capacities as well as the content of total soluble phenolics, anthocyanins, tannins, and flavonoids in the fruits and leaves of blueberries and lingonberries growing in Newfoundland. This study also determined the potential neuroprotective effect of extracts from fruits and leaves against glutamate-mediated excitotoxicity, which is believed to contribute to disorders such as stroke and neurodegenerative diseases. Lingonberry and blueberry plants were found to be rich sources of phenolic compounds. Total antioxidant capacities in terms of radical scavenging activity and reducing power were much higher in leaves of both plants as compared to their fruits. These results were in correlation with phenolic contents including total flavonoids, anthocyanins, and tannins. Brain-derived cell cultures from rats were prepared and grown for about 2 weeks. Cell cultures were treated with glutamate (100 μM) for 24 h, and the effect of extracts was determined on cells subjected to this excitotoxicity. Glutamate treatment caused approximately 23% cell loss when measured after 24 h of exposure. Whereas lingonberry fruit extract did not provide protection from glutamate toxicity, blueberry fruit extracts were extremely protective. Leaf extracts of both lingonberry and blueberry showed a significant neuroprotective effect. The greater protective effect of leaf extracts was in correlation with the levels of phenolics and antioxidant capacity. These findings suggest that berries or their components may contribute to protecting the brain from various pathologies.
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Affiliation(s)
- Poorva Vyas
- Department of Biology and ‡School of Pharmacy, Memorial University of Newfoundland , St. John's, Newfoundland, Canada A1B 3V6
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6
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Li Z, Guan R, Liu H. A Sensitive Reversed-Phase High-Performance Liquid Chromatography Method for the Quantitative Determination of Milk Xanthine Oxidase Activity. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojmc.2013.31004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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7
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Mehta A, Prabhakar M, Kumar P, Deshmukh R, Sharma PL. Excitotoxicity: bridge to various triggers in neurodegenerative disorders. Eur J Pharmacol 2012; 698:6-18. [PMID: 23123057 DOI: 10.1016/j.ejphar.2012.10.032] [Citation(s) in RCA: 438] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 09/26/2012] [Accepted: 10/06/2012] [Indexed: 12/13/2022]
Abstract
Glutamate is one of the most prominent neurotransmitter in the body, present in over 50% of nervous tissue and plays an important role in neuronal excitation. This neuronal excitation is short-lived and is followed by depression. Multiple abnormal triggers such as energy deficiency, oxidative stress, mitochondrial dysfunction, calcium overload, etc can lead to aberration in neuronal excitation process. Such an aberration, serves as a common pool or bridge between abnormal triggers and deleterious signaling processes with which central neurons cannot cope up, leading to death. Excitotoxicity is the pathological process by which nerve cells are damaged and killed by excessive stimulation by neurotransmitters such as glutamate and similar substances. Such excitotoxic neuronal death has been implicated in spinal cord injury, stroke, traumatic brain injury, hearing loss and in neurodegenerative diseases of the central nervous system such as stroke, epilepsy, multiple sclerosis, Alzheimer disease, Amyltropic lateral sclerosis, Parkinson's disease, Huntington disease and alcohol withdrawal. This review mainly emphasizes the triggering events which sustain neuronal excitation, role of calcium, mitochondrial dysfunction, ROS, NO, chloride homeostasis and eicosanoids pathways. Further, a brief introduction about the recent research occurring in the treatment of various neurodegenerative diseases, including a summary of the presumed physiologic mechanisms behind the pharmacology of these disorders.
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Affiliation(s)
- Ankita Mehta
- Neuropharmacology Division, ISF College of Pharmacy, Ferozpur Road, Ghal Kalan, Moga 142 001, Punjab, India
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8
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Atlante A, Bobba A, Paventi G, Pizzuto R, Passarella S. Genistein and daidzein prevent low potassium-dependent apoptosis of cerebellar granule cells. Biochem Pharmacol 2009; 79:758-67. [PMID: 19822130 DOI: 10.1016/j.bcp.2009.10.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2009] [Revised: 09/29/2009] [Accepted: 10/06/2009] [Indexed: 01/14/2023]
Abstract
We have investigated the ability of certain dietary flavonoids, known to exert beneficial effects on the central nervous system, to affect neuronal apoptosis. We used cerebellar granule cells undergoing apoptosis due to potassium deprivation in a serum-free medium in either the absence or presence of the flavonoids genistein and daidzein, which are present in soy, and of catechin and epicatechin, which are present in cocoa. These compounds were used in a blood dietary concentration range. We found that genistein and daidzein, but not catechin and epicatechin, prevented apoptosis, with cell survival measured 24h after the induction of apoptosis being higher than that of the same cells incubated in flavonoid free medium (80% and 40%, respectively); there was no effect in control cells. A detailed investigation of the effect of these compounds on certain mitochondrial events that occur in cells en route to apoptosis showed that genistein and daidzein prevented the impairment of glucose oxidation and mitochondrial coupling, reduced cytochrome c release, and prevented both impairment of the adenine nucleotide translocator and opening of the mitochondrial permeability transition pore. Interestingly, genistein and daidzein were found to reduce the levels of reactive oxygen species, which are elevated in cerebellar granule cell apoptosis. These findings strongly suggest that the prevention of apoptosis depends mainly on the antioxidant properties of genistein and daidzein. This could lead to the development of a flavonoid-based therapy in neuropathies.
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Affiliation(s)
- Anna Atlante
- Istituto di Biomembrane e Bioenergetica, CNR, Via G. Amendola 165/A, 70126 Bari, Italy
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9
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Kaminsky Y, Kosenko E. Brain purine metabolism and xanthine dehydrogenase/oxidase conversion in hyperammonemia are under control of NMDA receptors and nitric oxide. Brain Res 2009; 1294:193-201. [PMID: 19646976 DOI: 10.1016/j.brainres.2009.07.082] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Revised: 07/17/2009] [Accepted: 07/18/2009] [Indexed: 10/20/2022]
Abstract
In hyperammonemia, a decrease in brain ATP can be a result of adenine nucleotide catabolism. Xanthine dehydrogenase (XD) and xanthine oxidase (XO) are the end steps in the purine catabolic pathway and directly involved in depletion of the adenylate pool in the cell. Besides, XD can easily be converted to XO to produce reactive oxygen species in the cell. In this study, the effects of acute ammonia intoxication in vivo on brain adenine nucleotide pool and xanthine and hypoxanthine, the end degradation products of adenine nucleotides, during the conversion of XD to XO were studied. Injection of rats with ammonium acetate was shown to lead to the dramatic decrease in the ATP level, adenine nucleotide pool size and adenylate energy charge and to the great increase in hypoxanthine and xanthine 11 min after the lethal dose indicating rapid degradation of adenylates. Conversion of XD to XO in hyperammonemic rat brain was evidenced by elevated XO/XD activity ratio. Injection of MK-801, a NMDA receptor blocker, prevented ammonia-induced catabolism of adenine nucleotides and conversion of XD to XO suggesting that in vivo these processes are mediated by activation of NMDA receptors. The in vitro dose-dependent effects of sodium nitroprusside, a NO donor, on XD and XO activities are indicative of the direct modification of the enzymes by nitric oxide. This is the first report evidencing the increase in brain xanthine and hypoxanthine levels and adenine nucleotide breakdown in acute ammonia intoxication and NMDA receptor-mediated prevention of these alterations.
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Affiliation(s)
- Yury Kaminsky
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Russia.
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10
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Trnka J, Blaikie FH, Logan A, Smith RAJ, Murphy MP. Antioxidant properties of MitoTEMPOL and its hydroxylamine. Free Radic Res 2009; 43:4-12. [PMID: 19058062 PMCID: PMC2645131 DOI: 10.1080/10715760802582183] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Piperidine nitroxides such as TEMPOL have been widely used as antioxidants in vitro and in vivo. MitoTEMPOL is a mitochondria-targeted derivative of TEMPOL designed to protect mitochondria from the oxidative damage that they accumulate, but once there is rapidly reduced to its hydroxylamine, MitoTEMPOL-H. As little is known about the antioxidant efficacy of hydroxylamines, this study has assessed the antioxidant activity of both MitoTEMPOL and MitoTEMPOL-H. The hydroxylamine was more effective at preventing lipid-peroxidation than MitoTEMPOL and decreased oxidative damage to mitochondrial DNA caused by menadione. In contrast to MitoTEMPOL, MitoTEMPOL-H has no superoxide dismutase activity and its antioxidant actions are likely to be mediated by hydrogen atom donation. Therefore, even though MitoTEMPOL is rapidly reduced to MitoTEMPOL-H in cells, it remains an effective antioxidant. Furthermore, as TEMPOL is also reduced to a hydroxylamine in vivo, many of its antioxidant effects may also be mediated by its hydroxylamine.
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Affiliation(s)
- Jan Trnka
- MRC Dunn Human Nutrition Unit, Cambridge, UK
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11
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Dou D, Zheng X, Qin X, Qi H, Liu L, Raj JU, Gao Y. Role of cGMP-dependent protein kinase in development of tolerance to nitroglycerine in porcine coronary arteries. Br J Pharmacol 2007; 153:497-507. [PMID: 18037907 DOI: 10.1038/sj.bjp.0707600] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE The cGMP-dependent protein kinase (PKG) is a key enzyme for nitrovasodilator-induced vasodilation. The present study was to determine its role in nitrate tolerance. EXPERIMENTAL APPROACH isolated porcine coronary arteries were incubated for 24 h with nitroglycerin (NTG) and their relaxant responses were determined. PKG activity was assayed by measuring the incorporation of (32)P into BPDEtide. PKG protein was determined by Western blotting and PKG mRNA by real-time PCR. KEY RESULTS A 24 h incubation with NTG attenuated relaxation of coronary arteries to NTG, which was associated with decreased PKG activity. The nitrate tolerance induced with NTG at 10(-7) M was affected by a scavenger of reactive oxygen species and the tolerance induced with NTG at 10(-6) and 10(-5) M showed cross-tolerance to DETA NONOate and 8-Br-cGMP (a cell permeable cGMP analogue). PKG protein and mRNA were down-regulated by a 24 h incubation with NTG at 10(-5) M but not at 10(-7) M. Acute exposure to exogenous superoxide inhibited PKG activity stimulated by NTG at 10(-7) M but not at 10(-5) M. Superoxide had no effect on PKG activity stimulated with exogenous cGMP. CONCLUSIONS AND IMPLICATIONS Nitrate tolerance induced by NTG at low concentrations may result from an increased production of reactive oxygen species acting on sites upstream of PKG. The tolerance induced by NTG at higher concentrations may be in part due to suppression of PKG expression resulting from sustained activation of the enzyme. These distinct mechanisms of nitrate tolerance may be of clinical significance.
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Affiliation(s)
- D Dou
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
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12
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Cooper N, Khosravan R, Erdmann C, Fiene J, Lee JW. Quantification of uric acid, xanthine and hypoxanthine in human serum by HPLC for pharmacodynamic studies. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 837:1-10. [PMID: 16631418 DOI: 10.1016/j.jchromb.2006.02.060] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2005] [Revised: 02/27/2006] [Accepted: 02/28/2006] [Indexed: 11/20/2022]
Abstract
A simple HPLC method was developed and validated for the determination of uric acid (UA), xanthine (X) and hypoxanthine (HX) concentrations in human serum to support pharmacodynamic (PD) studies of a novel xanthine oxidase inhibitor during its clinical development. Serum proteins were removed by ultrafiltration. The hydrophilic analytes and the I.S. were eluted by 100% aqueous phosphate buffer mobile phase. The hydrophobic matrix components (late peaks) were eluted with a step gradient of a higher organic mobile phase. Validation on linearity, sensitivity, precision, accuracy, stability, and robustness of the method for PD biomarkers (UA, X, and HX) was carried out in a similar manner to that for pharmacokinetic (PK) data where applicable. Issues of selectivity for endogenous biomarker analytes and individual concentration variations were addressed during method validation. Standards were prepared in analyte-free phosphate buffer. Quality control samples were prepared in control serum from individuals not dosed with the xanthine oxidase inhibitor. The method was simple and robust with good accuracy and precision for the measurement of serum UA, X, and HX concentrations.
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13
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Abstract
Three routes have been identified triggering neuronal death under physiological and pathological conditions. Excess activation of ionotropic glutamate receptors cause influx and accumulation of Ca2+ and Na+ that result in rapid swelling and subsequent neuronal death within a few hours. The second route is caused by oxidative stress due to accumulation of reactive oxygen and nitrogen species. Apoptosis or programmed cell death that often occurs during developmental process has been coined as additional route to pathological neuronal death in the mature nervous system. Evidence is being accumulated that excitotoxicity, oxidative stress, and apoptosis propagate through distinctive and mutually exclusive signal transduction pathway and contribute to neuronal loss following hypoxic-ischemic brain injury. Thus, the therapeutic intervention of hypoxic-ischemic neuronal injury should be aimed to prevent excitotoxicity, oxidative stress, and apoptosis in a concerted way.
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Affiliation(s)
- Seok Joon Won
- Center for the Interventional Therapy of Stroke and Alzheimers Disease, Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchondong, Paldalgu, Suwon, Kyungkido 442-749, South Korea
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14
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Abe Y, Hashimoto Y, Tomita Y, Terashita K, Aiso S, Tajima H, Niikura T, Matsuoka M, Nishimoto I. Cytotoxic mechanisms by M239V presenilin 2, a little-analyzed Alzheimer's disease-causative mutant. J Neurosci Res 2004; 77:583-95. [PMID: 15264228 DOI: 10.1002/jnr.20163] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Although neurotoxic functions are well characterized in familial Alzheimer's disease (FAD)-linked N141I mutant of presenilin (PS)2, little has been known about M239V-PS2, another established FAD-causative mutant. We found that expression of M239V-PS2 caused neuronal cytotoxicity. M239V-PS2 exerted three forms of cytotoxicity: one was sensitive to both an antioxidant glutathione-ethyl-ester (GEE) and a caspase inhibitor Ac-DEVD-CHO (DEVD); the second was sensitive to GEE but resistant to DEVD; and the third was resistant to both. The GEE/DEVD-sensitive cytotoxicity by M239V-PS2 was likely through NADPH oxidase and the GEE-sensitive/DEVD-resistant cytotoxicity through xanthine oxidase (XO). Both mechanisms by M239V-PS2 were suppressed by pertussis toxin (PTX) and were mediated by Galpha(o), but not by Galpha(i). Although Abeta1-43 itself induced no cytotoxicity, Abeta1-43 potentiated all three components of M239V-PS2 cytotoxicity. As these cytotoxic mechanisms by M239V-PS2 are fully shared with N141I-PS2, they are most likely implicated in the pathomechanism of FAD by PS2 mutations. Notably, cytotoxicity by M239V-PS2 could be inhibited by the combination of two clinically usable inhibitors of superoxide-generating enzymes, apocynin and oxypurinol.
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Affiliation(s)
- Yoichiro Abe
- Department of Pharmacology, KEIO University School of Medicine, Tokyo, Japan
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15
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Hashimoto Y, Niikura T, Ito Y, Kita Y, Terashita K, Nishimoto I. Neurotoxic mechanisms by Alzheimer's disease-linked N141I mutant presenilin 2. J Pharmacol Exp Ther 2002; 300:736-45. [PMID: 11861776 DOI: 10.1124/jpet.300.3.736] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although it has been established that oxidative stress mediates cytotoxicity by familial Alzheimer's disease (FAD)-linked mutants of presenilin (PS)1 and that pertussis toxin inhibits cytotoxicity by FAD-linked N141I-PS2, it has not been determined whether oxidative stress is involved in cytotoxicity by N141I-PS2 or which pertussis toxin-sensitive proteins mediate the cytotoxicity. Here we report that low expression of N141I-PS2 caused neuronal cell death, whereas low expression of wild-type PS2 did not. Cytotoxicities by low and high expression of N141I-PS2 occurred through dissimilar mechanisms: the former cytotoxicity was blocked by a cell-permeable caspase inhibitor, and the latter was not. Since both mechanisms were sensitive to a cell-permeable antioxidant, we examined potential sources of reactive oxygen species in each mechanism, and found that the caspase inhibitor-sensitive neurotoxicity by N141I-PS2 was likely through NADPH oxidase and the caspase inhibitor-resistant neurotoxicity by N141I-PS2 through xanthine oxidase. Pertussis toxin greatly suppressed both toxic mechanisms by N141I-PS2, and only Galpha(o), a neuron-enriched pertussis toxin-sensitive G protein, was involved in both mechanisms. We therefore conclude that N141I-PS2 is capable of triggering multiple neurotoxic mechanisms, which can be inhibited by the combination of clinically usable inhibitors of NADPH oxidase and xanthine oxidase. This study thus provides a novel insight into the therapeutic intervention of PS2 mutant-associated FAD.
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Affiliation(s)
- Yuichi Hashimoto
- Department of Pharmacology and Neurosciences, KEIO University School of Medicine, Shinanomachi, Shinjuku-ku, Tokyo Japan
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Atlante A, Calissano P, Bobba A, Giannattasio S, Marra E, Passarella S. Glutamate neurotoxicity, oxidative stress and mitochondria. FEBS Lett 2001; 497:1-5. [PMID: 11376653 DOI: 10.1016/s0014-5793(01)02437-1] [Citation(s) in RCA: 252] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The excitatory neurotransmitter glutamate plays a major role in determining certain neurological disorders. This situation, referred to as 'glutamate neurotoxicity' (GNT), is characterized by an increasing damage of cell components, including mitochondria, leading to cell death. In the death process, reactive oxygen species (ROS) are generated. The present study describes the state of art in the field of GNT with a special emphasis on the oxidative stress and mitochondria. In particular, we report how ROS are generated and how they affect mitochondrial function in GNT. The relationship between ROS generation and cytochrome c release is described in detail, with the released cytochrome c playing a role in the cell defense mechanism against neurotoxicity.
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Affiliation(s)
- A Atlante
- Centro di sui Mitocondri e Metabolismo Energetico, CNR, Via G. Amendola 165lA, 70126 Bari, Italy
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