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Mughal TA, Ali S, Mumtaz S, Summer M, Saleem MZ, Hassan A, Hameed MU. Evaluating the biological (antidiabetic) potential of TEM, FTIR, XRD, and UV-spectra observed berberis lyceum conjugated silver nanoparticles. Microsc Res Tech 2024; 87:1286-1305. [PMID: 38351883 DOI: 10.1002/jemt.24509] [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: 11/22/2023] [Revised: 01/15/2024] [Accepted: 01/21/2024] [Indexed: 04/19/2024]
Abstract
Diabetes is a life-threatening disease that affects different parts of the body including the liver, kidney, and pancreas. The core root of diabetes is mainly linked to oxidative stress produced by reactive oxygen species (ROS). Berberis lyceum Royle (BLR) is the source of natural products. It comprises numerous bioactive compounds having antioxidant activities. In the current investigation, silver nanoparticles from BLR root extract were synthesized, characterized, and assessed for antidiabetic potential. UV spectrophotometry, Transmission electron microscopy (TEM), Fourier transform infra-red spectroscopy (FTIR), and x-ray diffraction (XRD) were applied for the characterization of NPs. It was evident from the morphological studies that the synthesized NPs were spherical and the average size was 11.02 nm. Results revealed that BLR-AgNPs showed higher radical scavenging activity as compared to BLR extract. Moreover, BLR-AgNPs displayed superior in vivo and in vitro antidiabetic activity in comparison to BLR extract. Glucose level (116.5 ± 5.1 mg/dL), liver function test (ALAT: 54.038 ± 6.2 IU/L; ASAT: 104.42 ± 13.9 IU/L; ALP: 192.6 ± 2.4 IU/L; bilirubin: 1.434 ± 0.14 mg/dL; total protein: 5.14 ± 0.24 mg/dL), renal function test (urea: 39.6 ± 0.63 mg/dL; uric acid: 21.4 ± 0.94 mg/dL; creatinine: 0.798 ± 0.03 mg/dL; albumin: 4.14 ± 0.2 mg/dL), lipid profile level (cholesterol: 101.62 ± 3 mg/dL; triglyceride: 110.42 ± 7 mg/dL; HDL-C: 29.7 ± 3 mg/dL; LDL-C: 47.056 ± 1 mg/dL; VLDL-C: 22.0 ± 1.3 mg/dL) and hematology (WBCs: 3.82 ± 0.24 103 /μL; RBCs: 4.78 ± 0.42 106 /μL; Hb: 12.6 ± 1.0 g/dL; Hematocrit: 39.4 ± 3.7%; MCV: 65.8 ± 3 fL; platelets: 312 ± 22.4; neutrophils: 34.8 ± 1.87; eosinophils: 3.08 ± 0.43; monocytes: 3.08 ± 0.28; lymphocytes: 75.6 ± 3.77) confirmed the significant antidiabetic potential of BLR-AgNPs. Histopathological examination authenticated that BLR-AgNPs caused a significant revival in the morphology of the liver, kidney, and pancreas. Hence, findings of the study suggested the BLR-AgNPs as a potent antidiabetic agent and could be an appropriate nanomedicine to prevent diabetes in future. RESEARCH HIGHLIGHTS: Berberis lyceum extract as a reducing, capping, and stabilization agent for the BLR-AgNPs synthesis Evaluation of α-amylase inhibition, antioxidant, and α-glucosidase inhibition potential Thorough characterization using Fourier transform infrared spectroscopy, Transmission electron microscopy, x-ray diffraction, and UV-VIS spectrophotometer, which is 1st of its kind In-vivo antidiabetic activity evaluation through multiple biomarkers.
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Affiliation(s)
- Tafail Akbar Mughal
- Department of Zoology, Women University of Azad Jammu & Kashmir, Bagh, Pakistan
| | - Shaukat Ali
- Medical Toxicology and Biochemistry Laboratory, Department of Zoology, Government College University, Lahore, Pakistan
| | - Shumaila Mumtaz
- Department of Zoology, University of Poonch, Rawalakot, Pakistan
| | - Muhammad Summer
- Medical Toxicology and Biochemistry Laboratory, Department of Zoology, Government College University, Lahore, Pakistan
| | - Muhammad Zubair Saleem
- Fujian Provincial Key Laboratory of Natural Medicine Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, China
| | - Ali Hassan
- Medical Toxicology and Biochemistry Laboratory, Department of Zoology, Government College University, Lahore, Pakistan
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Abd El-Twab SM, Abdul-Hamid M. Curcumin mitigates lithium-induced thyroid dysfunction by modulating antioxidant status, apoptosis and inflammatory cytokines. THE JOURNAL OF BASIC & APPLIED ZOOLOGY 2016; 76:7-19. [DOI: 10.1016/j.jobaz.2016.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Mansur RB, Santos CM, Rizzo LB, Cunha GR, Asevedo E, Noto MN, Pedrini M, Zeni M, Cordeiro Q, McIntyre RS, Brietzke E. Inter-relation between brain-derived neurotrophic factor and antioxidant enzymes in bipolar disorder. Bipolar Disord 2016; 18:433-9. [PMID: 27488494 DOI: 10.1111/bdi.12418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 06/28/2016] [Accepted: 07/01/2016] [Indexed: 12/23/2022]
Abstract
OBJECTIVES Accumulating evidence indicates that oxidative stress and neurotrophins have a bidirectional relationship. In this post hoc, exploratory analysis, we investigated the association between plasma brain-derived neurotrophic factor (BDNF) levels and activities of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD) in individuals with bipolar disorder (BD) and healthy controls. METHODS We measured plasma levels of BDNF and activities of GPx and SOD in individuals with BD (n=59) and healthy controls (n=26). Information related to current and past psychiatric/medical history, as well as to metabolic comorbidities, was also reported. RESULTS There were negative correlations between BDNF, GPx (r=-.449, P≤.001) and GPx/SOD ratio (r=-.503, P<.001), and a positive correlation between BDNF and SOD (r=.254, P=.020). There was a moderating effect of body mass index (BMI) on the association between BDNF and GPx/SOD rate ratio [(RR)=1.002, P=.034]; interactions between impaired glucose metabolism (IGM), GPx (RR=1.016, P=.033), and GPx/SOD ratio (RR=1.026, P=.002) were also observed. These results were significant in models that included age, gender, alcohol, tobacco and medication use. CONCLUSIONS There was a robust and independent correlation between peripheral BDNF and antioxidant enzyme activities in individuals with BD, which was moderated by metabolic comorbidities. These results reinforce the concept that these systems are associated and further extend knowledge of the putative effect of metabolic comorbidities in the pathophysiological substrates of BD.
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Affiliation(s)
- Rodrigo B Mansur
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.,Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada
| | - Camila M Santos
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Lucas B Rizzo
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.,Department of Psychiatry, Clinic for Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Graccielle R Cunha
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Elson Asevedo
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Mariane N Noto
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.,Vila Maria Outpatient Clinic, São Paulo, Brazil
| | - Mariana Pedrini
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Maiara Zeni
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Quirino Cordeiro
- Department of Psychiatry, Irmandade da Santa Casa de Misericórdia de São Paulo (ISCMSP), São Paulo, Brazil
| | - Roger S McIntyre
- Mood Disorders Psychopharmacology Unit (MDPU), University Health Network, University of Toronto, Toronto, Canada
| | - Elisa Brietzke
- Research Group in Behavioral Neuroscience of Bipolar Disorder (GP-TB), Department of Psychiatry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
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Kienhöfer D, Boeltz S, Hoffmann MH. Reactive oxygen homeostasis – the balance for preventing autoimmunity. Lupus 2016; 25:943-54. [DOI: 10.1177/0961203316640919] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Being mainly known for their role in the antimicrobial defense and collateral damage they cause in tissues as agents of oxidative stress, reactive oxygen species were considered “the bad guys” for decades. However, in the last years it was shown that the absence of reactive oxygen species can lead to the development of immune-mediated inflammatory diseases. Animal models of lupus, arthritis and psoriasis revealed reactive oxygen species-deficiency as a potent driver of pathogenesis. On the contrary, in chronic stages oxidative stress can still contribute to progression of inflammation. It seems that a neatly adjusted redox balance is necessary to sustain an immune state that both prevents the development of overt autoimmunity and attenuates chronic stages of disease.
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Affiliation(s)
- D Kienhöfer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Universitätsklinikum Erlangen, Department of Internal Medicine 3—Rheumatology and Immunology, Erlangen, Germany
| | - S Boeltz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Universitätsklinikum Erlangen, Department of Internal Medicine 3—Rheumatology and Immunology, Erlangen, Germany
| | - M H Hoffmann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Universitätsklinikum Erlangen, Department of Internal Medicine 3—Rheumatology and Immunology, Erlangen, Germany
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Oseni OA, Odesanmi OE, Oladele FC. Antioxidative and antidiabetic activities of watermelon (Citrullus lanatus) juice on oxidative stress in alloxan-induced diabetic male Wistar albino rats. Niger Med J 2016; 56:272-7. [PMID: 26759513 PMCID: PMC4697216 DOI: 10.4103/0300-1652.169707] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Background: The nutritional and medicinal importance of watermelon has been emphasized and its diseases preventive and curative power must be evaluated. Hence, this study was designed to evaluate the antioxidative and antidiabetic potentials of watermelon. Materials and Methods: The in vivo assay was carried out on 15 male albino rats which were divided into groups of three stages. In stage I, all animals received normal feeds and water for 1-week after, which five animals were selected and sacrificed for biochemical analyses which form the nondiabetic control, group. The remaining animals were fasted for 24 h before injected intra-peritoneally with a freshly prepared solution of alloxan at a dosage of 35 mg/kg body weight. Five out of the 10 rats were sacrificed as diabetic group while last five animals were fed with water melon juice for a week after, which they were sacrificed to form the treated group animals. In all the groups, body weights, fasting blood sugar, total protein level in the blood, and other biochemical parameters such as reduced glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA) concentration; catalase, and superoxide dismutase (SOD) % inhibition activities were determined. Results: The results of the biochemical analyses showed a significant increase in the concentration of blood glucose level after treatment with alloxan, which indicates that diabetic was induced. Hence, watermelon juice caused increased in weight, hypoglycemia; and increases in GSH, GPx, catalase, and SOD % inhibition activities with reduced MDA concentration after treatments. Conclusion: The watermelon juice resulted in the restoration of impaired conditions of the rats.
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Affiliation(s)
- O A Oseni
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, College of Medicine, Ekiti-State University, Ado-Ekiti, Nigeria
| | - O E Odesanmi
- Department of Science Laboratory Technology, Ekiti-State University, Ado-Ekiti, Nigeria
| | - F C Oladele
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, College of Medicine, Ekiti-State University, Ado-Ekiti, Nigeria
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Kong X, Ma MZ, Huang K, Qin L, Zhang HM, Yang Z, Li XY, Su Q. Increased plasma levels of the methylglyoxal in patients with newly diagnosed type 2 diabetes 2. J Diabetes 2014; 6:535-40. [PMID: 24720446 DOI: 10.1111/1753-0407.12160] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 03/09/2014] [Accepted: 04/07/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Methylglyoxal (MG) is a reactive-dicarbonyl that is thought to contribute to the development of diabetes either as a precursor for advanced glycation end products or as a direct toxin. The present study was designed to determine plasma MG level in patients with newly diagnosed type 2 diabetes mellitus (T2DM) and to evaluate the relationship between MG and other parameters, such as oxidative stress and metabolic indices. METHODS Methylglyoxal was measured by high-performance liquid chromatographic/tandem mass spectrometry in plasma from 48 subjects with newly diagnosed T2DM. The relationship between two variables was analyzed using Spearman's correlation analysis. Multiple stepwise linear regression analysis was used to assess the association of plasma MG and other parameters. RESULTS Plasma MG level in patients with newly diagnosed T2DM (65.2 ± 19.2 ng/mL) were significantly higher than that in control individuals (40.1 ± 11.1 ng/mL, P < 0.05). The plasma level of MG was positively correlated with the glycosylated hemoglobin A1c (HbA1c, r = 0.670, P < 0.01) and malondialdehyde (MDA, r = 0.694, P < 0.01). Multiple linear regression analysis revealed that both HbA1c and MDA are significant independent determinants of plasma MG level. CONCLUSIONS These findings suggest that increased plasma MG level is associated with the elevation of HbA1c and MDA in newly diagnosed T2DM patients.
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Affiliation(s)
- Xiang Kong
- Department of Endocrinology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Department of Pharmacology, Wannan Medical College, Wuhu, China
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Sánchez-Gómez FJ, Espinosa-Díez C, Dubey M, Dikshit M, Lamas S. S-glutathionylation: relevance in diabetes and potential role as a biomarker. Biol Chem 2014; 394:1263-80. [PMID: 24002664 DOI: 10.1515/hsz-2013-0150] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 06/10/2013] [Indexed: 02/06/2023]
Abstract
Glutathione is considered the main regulator of redox balance in the cellular milieu due to its capacity for detoxifying deleterious molecules. The oxidative stress induced as a result of a variety of stimuli promotes protein oxidation, usually at cysteine residues, leading to changes in their activity. Mild oxidative stress, which may take place in physiological conditions, induces the reversible oxidation of cysteines to sulfenic acid form, while pathological conditions are associated with higher rates of reactive oxygen species production, inducing the irreversible oxidation of cysteines. Among these, neurodegenerative disorders, cardiovascular diseases and diabetes have been proposed to be pathogenetically linked to this state. In diabetes-associated vascular complications, lower levels of glutathione and increased oxidative stress have been reported. S-glutathionylation has been proposed as a posttranslational modification able to protect proteins from over-oxidizing environments. S-glutathionylation has been identified in proteins involved in diabetic models both in vitro and in vivo. In all of them, S-glutathionylation represents a mechanism that regulates the response to diabetic conditions, and has been described to occur in erythrocytes and neutrophils from diabetic patients. However, additional studies are necessary to discern whether this modification represents a biomarker for the early onset of diabetic vascular complications.
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Sudhahar V, Urao N, Oshikawa J, McKinney RD, Llanos RM, Mercer JF, Ushio-Fukai M, Fukai T. Copper transporter ATP7A protects against endothelial dysfunction in type 1 diabetic mice by regulating extracellular superoxide dismutase. Diabetes 2013; 62:3839-50. [PMID: 23884884 PMCID: PMC3806617 DOI: 10.2337/db12-1228] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Oxidative stress and endothelial dysfunction contribute to vascular complication in diabetes. Extracellular superoxide dismutase (SOD3) is one of the key antioxidant enzymes that obtains copper via copper transporter ATP7A. SOD3 is secreted from vascular smooth muscles cells (VSMCs) and anchors at the endothelial surface. The role of SOD3 and ATP7A in endothelial dysfunction in type 1 diabetes mellitus (T1DM) is entirely unknown. Here we show that the specific activity of SOD3, but not SOD1, is decreased, which is associated with increased O2(•-) production in aortas of streptozotocin-induced and genetically induced Ins2(Akita) T1DM mice. Exogenous copper partially rescued SOD3 activity in isolated T1DM vessels. Functionally, acetylcholine-induced, endothelium-dependent relaxation is impaired in T1DM mesenteric arteries, which is rescued by SOD mimetic tempol or gene transfer of SOD3. Mechanistically, ATP7A expression in T1DM vessels is dramatically decreased whereas other copper transport proteins are not altered. T1DM-induced endothelial dysfunction and decrease of SOD3 activity are rescued in transgenic mice overexpressing ATP7A. Furthermore, SOD3-deficient T1DM mice or ATP7A mutant T1DM mice augment endothelial dysfunction and vascular O2(•-) production versus T1DM mice. These effects are in part due to hypoinsulinemia in T1DM mice, since insulin treatment, but not high glucose, increases ATP7A expression in VSMCs and restores SOD3 activity in the organoid culture of T1DM vessels. In summary, a decrease in ATP7A protein expression contributes to impaired SOD3 activity, resulting in O2(•-) overproduction and endothelial dysfunction in blood vessels of T1DM. Thus, restoring copper transporter function is an essential therapeutic approach for oxidant stress-dependent vascular and metabolic diseases.
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Affiliation(s)
- Varadarajan Sudhahar
- Section of Cardiology, Department of Medicine, and Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
| | - Norifumi Urao
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
| | - Jin Oshikawa
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
| | - Ronald D. McKinney
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
| | - Roxana M. Llanos
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, Australia
| | - Julian F.B. Mercer
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, Australia
| | - Masuko Ushio-Fukai
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
- Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
| | - Tohru Fukai
- Section of Cardiology, Department of Medicine, and Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois
- Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois
- Corresponding author: Tohru Fukai,
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Michael HN, Salib JY, Eskander EF. Bioactivity of Diosmetin Glycosides Isolated from the Epicarp of Date Fruits, Phoenix dactylifera
, on the Biochemical Profile of Alloxan Diabetic Male Rats. Phytother Res 2012; 27:699-704. [DOI: 10.1002/ptr.4777] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 06/03/2012] [Accepted: 06/09/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Helana Naguib Michael
- Chemistry of Tanning Materials Department; National Research Centre; Dokki Cairo Egypt
| | - Josline Yehia Salib
- Chemistry of Tanning Materials Department; National Research Centre; Dokki Cairo Egypt
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Wang X, Tao L, Hai CX. Redox-regulating role of insulin: the essence of insulin effect. Mol Cell Endocrinol 2012; 349:111-27. [PMID: 21878367 DOI: 10.1016/j.mce.2011.08.019] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 08/10/2011] [Accepted: 08/14/2011] [Indexed: 11/18/2022]
Abstract
It is well-known that insulin acts as an important hormone, controlling energy metabolism, cellular proliferation and biosynthesis of functional molecules to maintain a biological homeostasis. Over the past few years, intensive insulin therapy has been believed to be benefit for the outcome of diabetic patients, in which the suppression of oxidative stress plays a role. Moreover, insulin is accepted as a key component of glucose-insulin-potassium, a treatment which has been believed to exert significant cardiovascular protective effect via the reduction of oxidative stress. Furthermore, accumulating evidence has suggested that insulin exerts important redox-regulating actions in various insulin-sensitive target organs, implying the systematic antioxidative role of insulin as a hormone. It is time for us to revisit insulin effects, through summarizing and evaluating the novel functions of insulin and their mechanisms. This review focuses on the antioxidative effect of insulin and highlights insulin-induced regulation of various antioxidant enzymes via insulin signaling pathways and the cross talk between key transcription factors, including nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor κB (NF-κB) which are responsible for the transcription of antioxidant enzymes, leading to reduced generation of reactive oxygen species (ROS) and the enhancement of the elimination of ROS.
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Affiliation(s)
- Xin Wang
- Department of Toxicology, School of Preventive Medicine, The Fourth Military Medical University, Xi'an 710032, China
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Capellini VK, Baldo CF, Celotto AC, Batalhão ME, Cárnio EC, Rodrigues AJ, Evora PRB. Oxidative stress is not associated with vascular dysfunction in a model of alloxan-induced diabetic rats. ACTA ACUST UNITED AC 2011; 54:530-9. [PMID: 20857057 DOI: 10.1590/s0004-27302010000600004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Accepted: 07/06/2010] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To verify if an experimental model of alloxan-diabetic rats promotes oxidative stress, reduces nitric oxide bioavailability and causes vascular dysfunction, and to evaluate the effect of N-acetylcysteine (NAC) on these parameters. METHODS Alloxan-diabetic rats were treated or not with NAC for four weeks. Plasmatic levels of malondialdehyde (MDA) and nitrite/nitrate (NOx), the endothelial and inducible nitric oxide synthase (eNOS and iNOS) immunostaining and the vascular reactivity of aorta were compared among diabetic (D), treated diabetic (TD) and control (C) rats. RESULTS MDA levels increased in D and TD. NOx levels did not differ among groups. Endothelial eNOS immunostaining reduced and adventitial iNOS increased in D and TD. The responsiveness of rings to acetylcholine, sodium nitroprusside, and phenylephrine did not differ among groups. CONCLUSIONS NAC had no effect on the evaluated parameters and this experimental model did not promote vascular dysfunction despite the development of oxidative stress.
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Affiliation(s)
- Verena Kise Capellini
- Departamento de Cirurgia e Anatomia, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Piwkowska A, Rogacka D, Audzeyenka I, Jankowski M, Angielski S. High glucose concentration affects the oxidant-antioxidant balance in cultured mouse podocytes. J Cell Biochem 2011; 112:1661-72. [PMID: 21503956 DOI: 10.1002/jcb.23088] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hyperglycemia is well-recognized and has long-term complications in diabetes mellitus and diabetic nephropathy. In podocytes, the main component of the glomerular barrier, overproduction of reactive oxygen species (ROS) in the presence of high glucose induces dysfunction and increases excretion of albumin in urine. This suggests an impaired antioxidant defense system has a role in the pathogenesis of diabetic nephropathy. We studied expression of NAD(P)H oxidase subunits by Western blotting and immunofluorescence and the activities of the oxidant enzyme, NAD(P)H, and antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT), in mouse podocytes cultured in a high glucose concentration (30 mM). We found long-term (3 and 5 days) exposure of mouse podocytes to high glucose concentrations caused oxidative stress, as evidenced by increased expression of Nox4 and activities of NAD(P)H oxidase (Δ 182%) and SOD (Δ 39%) and decreased activities of GPx (Δ -40%) and CAT (Δ -35%). These biochemical changes were accompanied by a rise in intracellular ROS production and accumulation of hydrogen peroxide in extracellular space. The role of Nox4 in ROS generation was confirmed with Nox4 siRNA. In conclusion, high glucose concentration affects the oxidant-antioxidant balance in mouse podocytes, resulting in enhanced generation of superoxide anions and its attenuated metabolism. These observations suggest free radicals may play an important role in the pathogenesis of diabetic nephropathy.
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Affiliation(s)
- Agnieszka Piwkowska
- Mossakowski Medical Research Center Polish Academy of Sciences, Laboratory of Molecular and Cellular Nephrology, Gdańsk, Poland.
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Makni M, Sefi M, Garoui EM, Fetoui H, Boudawara T, Zeghal N. Dietary polyunsaturated fatty acid prevents hyperlipidemia and hepatic oxidant status in pregnant diabetic rats and their macrosomic offspring. J Diabetes Complications 2011; 25:267-74. [PMID: 21458299 DOI: 10.1016/j.jdiacomp.2011.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Accepted: 02/15/2011] [Indexed: 02/02/2023]
Abstract
A considerable amount of clinical and experimental evidence now exists and suggests the involvement of fatty acids and free radical-mediated oxidative processes in the pathogenesis of diabetic complications. Fetuses from diabetic mothers are at increased risk of developing neonatal macrosomia and oxidative stress. We investigated the modulation of antioxidant status and liver biochemical parameters in normal and diabetic pregnant rats and their offspring. Animals were randomly allocated into three groups of six rats each: a control group, a diabetic group and diabetic rats fed with flax and sesame seeds mixture group. The time course of changes in lipid metabolism and antioxidant status by dietary rich in ω3- and ω6-polyunsaturated fatty acids in alloxan-induced diabetic pregnant rats and their macrosomic offspring was studied. Glucose and insulin levels were also assessed in order to characterize the diabetic state of dams and their offspring. The diabetic rats presented a significant increase in glycemia, plasma and liver lipid parameters compared with those of control group. In addition, liver malonaldialdehyde levels significantly increased. Antioxidant enzyme activities such as catalase and superoxide dismutase and reduced glutathione levels significantly decreased in the liver of diabetic rats when compared with controls. Diet supplemented with flax and sesame seeds mixture in pregnant diabetic rats ameliorated lipid parameters, antioxidant enzyme activities, level of reduced glutathione and significantly decreased malonaldialdehyde levels. These ameliorations were also observed in pups whose pregnant diabetic mothers were fed seeds mixture. Our results suggested that flax and sesame seeds mixture supplemented to diet of pregnant diabetic rats might be helpful in preventing diabetic complications in adult dams and their offspring.
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Affiliation(s)
- Mohamed Makni
- Animal Physiology Laboratory, Faculty of Sciences, BP1171, 3000 Sfax. University of Sfax, Tunisia
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Eliza J, Daisy P, Ignacimuthu S. Antioxidant activity of costunolide and eremanthin isolated from Costus speciosus (Koen ex. Retz) Sm. Chem Biol Interact 2010; 188:467-72. [DOI: 10.1016/j.cbi.2010.08.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Revised: 08/05/2010] [Accepted: 08/09/2010] [Indexed: 02/02/2023]
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Abstract
Vascular disease in hypertension and diabetes is associated with increased oxidants. The oxidants arise from NADPH oxidase, xanthine oxidase, and mitochondria. Superoxide anion and hydrogen peroxide are produced by both leukocytes and vascular cells. Nitric oxide is produced in excess by inducible nitric oxide synthase, and the potent oxidant, peroxynitrite, is formed from superoxide and nitric oxide. The damage to proteins caused by oxidants is selective, affecting specific oxidant-sensitive amino acid residues. With some important vascular proteins, for example, endothelial nitric oxide synthase, prostacycline synthase, and superoxide dismutase, oxidation of a single susceptible amino acid inactivates the enzyme. The beneficial effects of antioxidants, at least in animal models of hypertension and diabetes, can in part be ascribed to protection of these and other proteins. Mutant proteins lacking their reactive constituent can recapitulate some disease phenotypes suggesting a pathogenic role of the oxidation. Thus, many of the shared functional abnormalities of hypertensive and diabetic blood vessels may be caused by oxidants. Although studies using antioxidants have failed in patients, the successful treatment of vascular disease with HMG-CoA reductase inhibitors, thromboxane A2 antagonists, and polyphenols may depend on their anti-inflammatory effects and ability to decrease production of damaging oxidants.
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Duzguner V, Kaya S. Effect of zinc on the lipid peroxidation and the antioxidant defense systems of the alloxan-induced diabetic rabbits. Free Radic Biol Med 2007; 42:1481-6. [PMID: 17448894 DOI: 10.1016/j.freeradbiomed.2007.02.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 01/17/2007] [Accepted: 02/01/2007] [Indexed: 10/23/2022]
Abstract
The effects of oral zinc supplementation on lipid peroxidation and the antioxidant defense system of alloxan (80-90 mg/kg)-induced diabetic rabbits were examined. Forty-five New Zealand male rabbits, 1 year old, weighing approximately 2.5 kg, were allocated randomly and equally as control, diabetic, and zinc-supplemented diabetic groups. After diabetes was induced, zinc-supplemented diabetic rabbits had 150 mg/L of zinc as zinc sulfate (ZnSO(4)) in their drinking tap water for 3 months. The feed and water consumption was higher in diabetic groups than (P<0.01) healthy rabbits. The body weight was lower in diabetic rabbits compared to control. The blood glucose levels were higher in diabetic groups than controls. The elevated plasma malondialdehyde (MDA) levels were determined in the diabetic group (P<0.01). The glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), and ceruloplasmin levels in the diabetic group were decreased by the effect of diabetes but there was no difference between zinc-supplemented diabetic and control rabbits. Serum zinc concentrations were lower in diabetic rabbits but iron (Fe) and copper (Cu) levels in sera were not different among the groups. As a result, it was concluded that daily zinc supplementation could reduce the harmful effects of oxidative stress in diabetics.
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Affiliation(s)
- Vesile Duzguner
- Department of Biochemistry, Institute of Health Sciences, Mustafa Kemal University, 31034 Hatay, Turkey
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Li S, Li X, Li YL, Shao CH, Bidasee KR, Rozanski GJ. Insulin regulation of glutathione and contractile phenotype in diabetic rat ventricular myocytes. Am J Physiol Heart Circ Physiol 2006; 292:H1619-29. [PMID: 17056675 DOI: 10.1152/ajpheart.00140.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Cardiovascular complications of diabetes mellitus involve oxidative stress and profound changes in reduced glutathione (GSH), an essential tripeptide that controls many redox-sensitive cell functions. This study examined regulation of GSH by insulin to identify mechanisms controlling cardiac redox state and to define the functional impact of GSH depletion. GSH was measured by fluorescence microscopy in ventricular myocytes isolated from Sprague-Dawley rats made diabetic by streptozotocin, and video and confocal microscopy were used to measure mechanical properties and Ca(2+) transients, respectively. Spectrophotometric assays of tissue extracts were also done to measure the activities of enzymes that control GSH levels. Four weeks after injection of streptozotocin, mean GSH concentration ([GSH]) in isolated diabetic rat myocytes was approximately 36% less than in control, correlating with decreased activities of two major enzymes regulating GSH levels: glutathione reductase and gamma-glutamylcysteine synthetase. Treatment of diabetic rat myocytes with insulin normalized [GSH] after a delay of 3-4 h. A more rapid but transient upregulation of [GSH] occurred in myocytes treated with dichloroacetate, an activator of pyruvate dehydrogenase. Inhibitor experiments indicated that insulin normalized [GSH] via the pentose pathway and gamma-glutamylcysteine synthetase, although the basal activity of glucose-6-phosphate dehydrogenase was not different between diabetic and control hearts. Diabetic rat myocytes were characterized by significant mechanical dysfunction that correlated with diminished and prolonged Ca(2+) transients. This phenotype was reversed by in vitro treatment with insulin and also by exogenous GSH or N-acetylcysteine, a precursor of GSH. Our data suggest that insulin regulates GSH through pathways involving de novo GSH synthesis and reduction of its oxidized form. It is proposed that a key function of glucose metabolism in heart is to supply reducing equivalents required to maintain adequate GSH levels for the redox control of Ca(2+) handling proteins and contraction.
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Affiliation(s)
- Shumin Li
- Dept of Cellular and Integrative Physiology, Univ of Nebraska College of Medicine, 985850 Nebraska Medical Center, Omaha, NE 68198-5850, USA
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19
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Beisswenger PJ, Drummond KS, Nelson RG, Howell SK, Szwergold BS, Mauer M. Susceptibility to diabetic nephropathy is related to dicarbonyl and oxidative stress. Diabetes 2005; 54:3274-81. [PMID: 16249455 DOI: 10.2337/diabetes.54.11.3274] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Dicarbonyl and oxidative stress may play important roles in the development of diabetes complications, and their response to hyperglycemia could determine individual susceptibility to diabetic nephropathy. This study examines the relationship of methylglyoxal, 3-deoxyglucosone (3DG), and oxidative stress levels to diabetic nephropathy risk in three populations with diabetes. All subjects in the Overt Nephropathy Progressor/Nonprogressor (ONPN) cohort (n = 14), the Natural History of Diabetic Nephropathy study (NHS) cohort (n = 110), and the Pima Indian cohort (n = 45) were evaluated for clinical nephropathy, while renal structural measures of fractional mesangial volume [Vv(Mes/glom)] and glomerular basement membrane (GBM) width were determined by electron microscopy morphometry in the NHS and Pima Indian cohorts. Methylglyoxal and 3DG levels reflected dicarbonyl stress, while reduced glutathione (GSH) and urine 8-isoprostane (8-IP) measured oxidative stress. Cross-sectional measures of methylglyoxal production by red blood cells incubated in 30 mmol/l glucose were increased in nephropathy progressors relative to nonprogressors in the ONPN (P = 0.027) and also reflected 5-year GBM thickening in the NHS cohort (P = 0.04). As nephropathy progressed in the NHS cohort, in vivo levels of methylglyoxal (P = 0.036), 3DG (P = 0.004), and oxidative stress (8-IP, P = 0.007 and GSH, P = 0.005) were seen, while increased methylglyoxal levels occurred as nephropathy progressed (P = 0.0016) in the type 2 Pima Indian cohort. Decreased glyceraldehyde-3-phosphate dehydrogenase activity also correlated with increased methylglyoxal levels (P = 0.003) in the NHS cohort. In conclusion, progression of diabetic nephropathy is significantly related to elevated dicarbonyl stress and possibly related to oxidative stress in three separate populations, suggesting that these factors play a role in determining individual susceptibility.
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Affiliation(s)
- Paul J Beisswenger
- Department of Medicine, Diabetes, Endocrinology and Metabolism, Dartmouth Medical School and Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA.
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Gumieniczek A. Effects of repaglinide on oxidative stress in tissues of diabetic rabbits. Diabetes Res Clin Pract 2005; 68:89-95. [PMID: 15860235 DOI: 10.1016/j.diabres.2004.09.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Revised: 09/02/2004] [Accepted: 09/06/2004] [Indexed: 01/09/2023]
Abstract
In this study, the antioxidative properties of repaglinide were examined in tissues of alloxan-induced diabetic rabbits. Glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R) and protein carbonyl groups (PCG) were measured after 4 and 8 weeks treatment with repaglinide (0.3 mg/kg daily). In liver, diabetic versus control values (mean +/- S.E.M., p<0.05) for GSH-Px were 181.0 +/- 5.4 mU/mg protein versus 203.1 +/- 1.9 mU/mg protein and 187.4 +/- 6.6 mU/mg protein versus 240.9 +/- 18.8 mU/mg protein. The respective values for GSH were 33.7 +/- 0.4 nmol/mg protein versus 49.0 +/- 1.6 nmol/mg protein and 37.7 +/- 1.0 nmol/mg protein versus 41.2 +/- 0.7 nmol/mg protein. In diabetic kidney, GSSG-R activity (20.6 +/- 1.6 mU/mg protein versus 32.4 +/- 1.5 mU/mg protein and 23.6 +/- 0.6 mU/mg protein versus 36.3 +/- 0.3 mU/mg protein) and GSH level (16.6 +/- 0.5 nmol/mg protein versus 23.2 +/- 0.9 nmol/mg protein and 17.9 +/- 0.5 nmol/mg protein versus 23.2 +/- 0.6 nmol/mg protein) were reduced compared to control. PCG level was elevated in diabetic liver (0.58 +/- 0.02 nmol/mg protein versus 0.16 +/- 0.03 nmol/mg protein at 4 weeks and 0.64 +/- 0.04 nmol/mg protein versus 0.16 +/- 0.03 nmol/mg protein at 8 weeks) and in diabetic kidney (0.32 +/- 0.03 nmol/mg protein versus 0.11 +/- 0.02 nmol/mg protein and 0.35 +/- 0.03 nmol/mg protein versus 0.16 +/- 0.03 nmol/mg protein). Repaglinide did not affect the glucose level but reduced to some extent the oxidative stress enhanced by chronic hyperglycemia. In diabetic kidney, it restored to control values GSSG-R activity (45.4 +/- 2.0 mU/mg protein at 4 weeks and 41.1 +/- 0.07 mU/mg protein at 8 weeks), GSH level (27.0 +/- 0.8 and 26.8 +/- 0.9 nmol/mg protein), and partly PCG level (0.17 +/- 0.02 nmol/mg protein at 8 weeks). The treatment partly affected GSH-Px activity (262.7 +/- 17.6 mU/mg protein) and GSH level (40.4 +/- 1.4 nmol/mg protein) in diabetic liver. This study shows that repaglinide produces measurable antioxidative effects at therapeutic dose.
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Affiliation(s)
- Anna Gumieniczek
- Department of Medicinal Chemistry, Medical University of Lublin, Chodzki Street 6, 20-093 Lublin, Poland.
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Gumieniczek A. Effects of pioglitazone on hyperglycemia-induced alterations in antioxidative system in tissues of alloxan-treated diabetic animals. ACTA ACUST UNITED AC 2005; 56:321-6. [PMID: 15816361 DOI: 10.1016/j.etp.2004.12.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hyperglycemia not only generates reactive oxygen species but also attenuates antioxidant mechanisms creating a state of oxidative stress. Oxidative stress is thought to play a crucial role in pathogenesis of chronic diabetic complications. Pioglitazone is a new oral antidiabetic agent, a potent inhibitor of glycation and potent antioxidant. In the present study, normoglycemic and alloxan-induced diabetic rabbits were treated with pioglitazone (1 mg/kg daily) for 4 and 8 weeks. At the end, glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R), glutathione (GSH) and protein carbonyl groups (PCG) were evaluated in homogenates of liver and kidney. Chronic hyperglycemia caused a marked increase in oxidative processes and some changes in activity of antioxidants. In liver, diabetic vs. control values (mean+/-S.E.M; P<0.05) for GSH-Px were 181.0+/-5.4 vs. 203.1+/-1.9 and 187.4+/-6.6 vs. 240.9+/-18.8mU/mg protein. Pioglitazone treatment for 8 weeks affected GSH-Px activity in diabetic liver (261.5+/-7.3 mU/mg protein). In diabetic kidney, GSSG-R activity (20.6+/-1.6 vs. 32.4+/-1.5 and 23.6+/-0.6 vs. 36.3+/-0.3 mU/mg protein) and GSH level (16.6+/-0.5 vs. 23.2+/-0.9 and 17.9+/-0.5 vs. 23.2+/-0.6 nmol/mg protein) were diminished, while PCG level (0.32+/-0.03 vs. 0.11+/-0.02 and 0.35+/-0.03 vs. 0.16+/-0.03 nmol/mg protein) was elevated. In diabetic kidney, pioglitazone restored to control values GSSG-R activity (34.4+/-1.4 and 30.6+/-0.1 mU/mg protein) as well as GSH (25.5+/-1.2 and 21.6+/-0.5 nmol/mg protein) and PCG (0.16+/-0.01 and 0.19+/-0.02 nmol/mg protein) levels. The present study showed that pioglitazone reduced to some extent the oxidative stress enhanced by chronic hyperglycemia.
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Affiliation(s)
- Anna Gumieniczek
- Department of Medicinal Chemistry, Faculty of Pharmacy, Medical University of Lublin, 20-093 Lublin, Poland.
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Weidig P, McMaster D, Bayraktutan U. High glucose mediates pro-oxidant and antioxidant enzyme activities in coronary endothelial cells. Diabetes Obes Metab 2004; 6:432-41. [PMID: 15479219 DOI: 10.1111/j.1462-8902.2004.00364.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM Excess levels of free radicals such as nitric oxide (NO) and superoxide anion (O(2)(-)) are associated with the pathogenesis of endothelial cell dysfunction in diabetes mellitus. This study was designed to investigate the underlying causes of oxidative stress in coronary microvascular endothelial cells (CMECs) exposed to hyperglycaemia. METHODS CMECs were cultured under normal (5.5 mmol/l) or high glucose (22 mmol/l) concentrations for 7 days. The activity and expression (protein level) of endothelial NO synthase (eNOS), inducible NOS (iNOS), NAD(p)H oxidase and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were investigated by specific activity assays and Western analyses, respectively, while the effects of hyperglycaemia on nitrite and O(2)(-) generation were investigated by Griess reaction and cytochrome C reduction assay, respectively. RESULTS Hyperglycaemia did not alter eNOS or iNOS protein expressions and overall nitrite generation, an index of NO production. However, it significantly reduced the levels of intracellular antioxidant glutathione by 50% (p < 0.05) and increased the protein expressions and activities of p22-phox, a membrane-bound component of pro-oxidant NAD(p)H oxidase and antioxidant enzymes (p < 0.05). Free radical scavengers, namely, Tiron and mercaptopropionylglycine (MPG) (0.1-1 micromol/l) reduced hyperglycaemia-induced antioxidant enzyme activity and increased glutathione and nitrite generation to the levels observed in CMEC cultured in normoglycaemic medium (p < 0.01). The differences in enzyme activity and expressions were independent of the increased osmolarity generated by high glucose levels as investigated by using equimolar concentrations of mannitol in parallel experiments. CONCLUSIONS These results suggest that hyperglycaemia-induced oxidative stress may arise in CMEC as a result of enhanced pro-oxidant enzyme activity and diminished generation of antioxidant glutathione. By increasing the antioxidant enzyme capacity, CMEC may protect themselves against free radical-induced cell damage in diabetic conditions.
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Affiliation(s)
- P Weidig
- Department of Medicine, Institute of Clinical Science Block B, Queen's University Belfast, Belfast BT12 6BJ, UK
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Ulker S, McMaster D, McKeown PP, Bayraktutan U. Antioxidant vitamins C and E ameliorate hyperglycaemia-induced oxidative stress in coronary endothelial cells. Diabetes Obes Metab 2004; 6:442-51. [PMID: 15479220 DOI: 10.1111/j.1462-8902.2004.00443.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Vitamins C and E have protective features in many disease states associated with enhanced oxidative stress. The aim of this study was to investigate whether vitamin(s) C and/or E modulate hyperglycaemia-induced oxidative stress by regulating enzymatic activities of prooxidant, i.e. NAD(P)H oxidase and/or antioxidant enzymes, namely endothelial nitric oxide synthase (eNOS), superoxide dismutase, catalase and glutathione peroxidase, using coronary microvascular endothelial cells (CMEC). METHODS CMEC were cultured under normal (5.5 mM) or high glucose (22 mM) concentrations for 7 days. The enzyme activities were determined by specific assays. The levels of O(2) (-) and nitrite were measured by cytochrome c reduction and Griess assays respectively. RESULTS Hyperglycaemia did not alter eNOS activity or overall nitrite generation, an index of NO production. However, it increased NAD(P)H oxidase and antioxidant enzyme activities (p < 0.05). Specific inhibitors of NAD(P)H oxidase, i.e. phenylarsine oxide (0.1-3 microm) and 4-(2-aminoethyl)benzenesulfonyl fluoride (5-100 microm) and vitamins C and E (0.1-1 microm) significantly reduced prooxidant and antioxidant enzyme activities in CMEC exposed to hyperglycaemia (p < 0.01). The differences in enzyme activities were independent of increases in osmolarity generated by high glucose levels as investigated by using equimolar concentrations of mannitol in parallel experiments. CONCLUSIONS Vitamins C and E may protect CMEC against hyperglycaemia-induced oxidative stress by concomitantly regulating prooxidant and antioxidant enzyme activities.
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Affiliation(s)
- S Ulker
- Department of Medicine, Institute of Clinical Science Block B, Queen's University Belfast, Belfast BT12 6BJ, UK
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Shukla N, Thompson CS, Angelini GD, Mikhailidis DP, Jeremy JY. Low micromolar concentrations of copper augment the impairment of endothelium-dependent relaxation of aortae from diabetic rabbits. Metabolism 2004; 53:1315-21. [PMID: 15375788 DOI: 10.1016/j.metabol.2004.05.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Both diabetes mellitus (DM) and elevated plasma copper concentrations are risk factors for cardiovascular disease (CVD). DM is associated with impaired endothelial nitric oxide (NO) and with excess superoxide (O2*-) formation. Copper is also elevated in DM and is also associated with the generation of O2*-. To explore possible interactions between DM and copper, the effect of exogenous copper (CuCl2) on endothelium-dependent relaxation and cyclic guanosine monophosphate (GMP) formation was investigated in aortae from diabetic rabbits. Rabbits were rendered diabetic by intravenous injection of alloxan. Six months after induction of DM, the aortae were excised, cut into rings, and mounted in an organ bath for isometric measurement of acetylcholine (Ach)-evoked relaxation in rings precontracted with phenylephrine (PE). In parallel studies, cyclic (c)GMP formation by aortic rings following stimulation with Ach, calcium ionophore A23187 (A23187) and sodium nitroprusside (SNP) was assessed using radioimmunoassay. The effect of copper on these parameters was then studied using the same methods. Ach-evoked relaxation and Ach- and A23187-evoked cGMP formation were significantly impaired in aortae from diabetic rabbits compared to controls, effects that were reversed with superoxide dismutase (SOD) and catalase (CAT). In contrast, there were no significant differences in SNP-stimulated relaxation or cGMP formation in aortae from diabetic rabbits compared to controls. Copper (1 to 10 micromol/L) promoted a further significant inhibition of Ach-stimulated relaxation in aortae from diabetic but not control rabbits. This reduction by copper was again reversed by SOD and CAT. We conclude that copper augments the reduction of NO bioavailability, which is already impaired in aortae from diabetic rabbits due to excess production of O2*- and H2O2. These results indicate that patients with DM may be susceptible to copper-mediated vasculopathy at much lower concentrations than those that promote vasculopathy in nondiabetic patients.
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Affiliation(s)
- N Shukla
- Bristol Heart Institute, University of Bristol, UK
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Damasceno DC, Volpato GT, Calderon IDMP, Aguilar R, Rudge MVC. Effect of Bauhinia forficata extract in diabetic pregnant rats: maternal repercussions. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2004; 11:196-201. [PMID: 15070172 DOI: 10.1078/0944-7113-00348] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Bauhinia forficata, commonly known as "paw-of-cow", is widely used in Brazil folk medicine for the treatment of Diabetes mellitus. The purposes of present study were to determine the repercussions of diabetes on the defense system against oxidative stress in pregnant female rats and to characterize the influence of the treatment with Bauhinia forficata extract on the antioxidant system, glycemic control, hepatic glycogen, cholesterol, triglycerides, total proteins and lipids. Virgin female Wistar rats were injected with 40 mg/kg streptozotocin (STZ) before mating. Oral administration of an aqueous extract of Bauhinia forficata leaves was given to non-diabetic and diabetic pregnant rats in 3 doses: 500 mg/kg from 0 to 4th day of pregnancy, 600 mg/kg from 5th to 14th day and 1000 mg/kg from 15th to 20th day. All the females were killed on the day 21 of pregnancy. A maternal blood sample was collected by venous puncture and the maternal liver was removed for biochemical measurement. The diabetic pregnant rats presented hyperglycemia, hyperlipemia, hypertriglyceridemia, hypercholesterolemia, hyperuricemia, decreased determinations of reduced glutathione (GSH) and superoxide dismutase (SOD). Treatment with B. forficata extract did not interfere in the albumin, total protein and lipid, triglyceride, cholesterol and SOD determinations. Increased hepatic glycogen, decreased uric acid concentration and increased GSH activity was observed. This last fact suggests that the plant may have some action on antioxidant defense system. However, the demonstration of the active component present in B. forficata responsible for its antioxidant effect and the increase in hepatic glycogen deserve further investigation.
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Affiliation(s)
- D C Damasceno
- Discipline of Human Embryology, School of Medicine of Marilia, São Paulo State, Brazil.
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Gumieniczek A. Effect of the new thiazolidinedione-pioglitazone on the development of oxidative stress in liver and kidney of diabetic rabbits. Life Sci 2004; 74:553-62. [PMID: 14623026 DOI: 10.1016/j.lfs.2003.03.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Impaired homeostasis under diabetic conditions is connected with the increased production of free radicals and deficiency of antioxidative systems. The aim of this study was to analyze the effect of new oral antidiabetic drug-pioglitazone on activity of antioxidant factors and lipid peroxidation in vivo. The liver and kidney of alloxan-induced diabetic rabbits were examined after 4 and 8 weeks of treatment. After 4 weeks of diabetes the superoxide dismutase (Cu,Zn-SOD) activity in the liver was diminished while the catalase (CAT) activity and the level of ascorbic acid (AA) were elevated in comparison with the control group. Pioglitazone treatment during 4 weeks decreased the catalase activity in relation to the control diabetic animals. After 8 weeks of diabetes the CAT activity in the liver was elevated in comparison with the control group. Pioglitazone treatment during 8 weeks decreased the CAT activity and the level of lipid peroxidation products (LPO), and increased the Cu,Zn-SOD activity in relation to control diabetic animals. After 4 weeks of diabetes in the kidney the Cu,Zn-SOD activity and the level of ascorbic acid (AA) were diminished while the CAT activity and the LPO level were elevated in comparison with the control group. Pioglitazone treatment during 4 weeks increased the AA and decreased the LPO levels in relation to non-treated diabetic animals. After 8 weeks of disease the Cu,Zn-SOD activity in the kidney was diminished in comparison with the control group. Pioglitazone during 8 weeks decreased the LPO level in relation to non-treated diabetic animals. This study shows that diabetic animals undergo an important oxidative stress, which is partially corrected by pioglitazone treatment.
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Affiliation(s)
- Anna Gumieniczek
- Department of Medicinal Chemistry, Faculty of Pharmacy, Medical University of Lublin, Chodźki Str 6, 20-093 Lublin, Poland.
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Abstract
Endothelins are widely distributed in the body and perform several vascular and nonvascular functions. Experimental data indicate abnormalities of the endothelin system in several organs affected in chronic diabetic complications. In support of this notion, it has been shown that endothelin-receptor antagonists prevent structural and functional abnormalities in target organs of diabetic complications in animal models. Alterations of plasma endothelin levels have also been demonstrated in human diabetes. This review discusses the role of endothelins in the pathogenesis of chronic diabetic complications. The current experimental evidence suggests that endothelin-receptor antagonism may potentially be an adjuvant therapeutic tool in the treatment of chronic diabetic complications.
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Affiliation(s)
- Zia Ali Khan
- Department of Pathology, University of Western Ontario, London, ON N6A 5C1, Canada
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Limaye PV, Raghuram N, Sivakami S. Oxidative stress and gene expression of antioxidant enzymes in the renal cortex of streptozotocin-induced diabetic rats. Mol Cell Biochem 2003; 243:147-52. [PMID: 12619900 DOI: 10.1023/a:1021620414979] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The present study was aimed at addressing the effect of hyperglycemia on antioxidant enzymes. The expression of catalase, superoxide dismutase and glutathione peroxidase, the three primary scavenger enzymes involved in detoxifying reactive oxygen species has been evaluated in the renal cortex of rats after 6 weeks of streptozotocin-induced diabetes. Lipid peroxidation and protein oxidation in the renal cortical homogenate were first performed to confirm a state of oxidative stress. The enzyme assays showed significant and varied alterations in catalase, superoxide dismutase and glutathione peroxidase activities. An opposing response of catalase and glutathione peroxidase activities to diabetes was observed. RT-PCR analysis was used to ascertain whether steady-state transcription levels were altered. While an increase in glutathione peroxidase and Cu-Zn superoxide dismutase mRNA parallels the increase in the activities of the enzymes, an increase in catalase gene expression in contrast to a decrease in enzyme activity suggests a role for post-translational modification in altering the activity of this enzyme.
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Affiliation(s)
- Pallavi V Limaye
- Department of Life Sciences, University of Mumbai, Santacruz (E), Mumbai, India
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29
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Damasceno DC, Volpato GT, de Mattos Paranhos Calderon I, Cunha Rudge MV. Oxidative stress and diabetes in pregnant rats. Anim Reprod Sci 2002; 72:235-44. [PMID: 12137985 DOI: 10.1016/s0378-4320(02)00094-5] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A considerable amount of clinical and experimental evidence now exists suggesting the involvement of free radical-mediated oxidative processes in the pathogenesis of diabetic complications. If the diabetic state is associated with a generalized increase in oxidative stress, it might well be reflected in the alterations in embryonic and fetal development during pregnancy. In the present study, incidence of the malformed fetuses, biochemical parameters and antioxidant system activity of streptozotocin (STZ)-induced diabetic pregnant rats was investigated and the results obtained were compared with those of the control group (non-diabetic). Virgin female Wistar rats were injected with 40 mg/kg streptozotocin (STZ) before mating. All the females were killed on Day 21 of pregnancy and the fetuses were analyzed. A maternal blood sample was collected by venous puncture and the maternal liver was removed for biochemical measurement. The diabetic dams presented hyperglycemia, hyperlipemia, hypertriglyceridemia, hypercholesterolemia, hyperuricemia, decreased reduced glutathione (GSH), hepatic glycogen and superoxide dismutase (SOD) determinations. There was an increased incidence of skeletal and visceral malformation in fetuses from diabetic rats. Our findings suggest that oxidative stress occurs in the diabetic pregnant state, which might promote maternal homeostasis alterations. These diabetic complications might be a contributory factor to conceptus damage causing embryonic death (abortion/miscarriage) or the appearance of malformations in the fetuses of diabetic dams. Antioxidant treatment of women with diabetes may be important in future attempts to prevent congenital malformations.
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30
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Mîinea C, Kuruvilla R, Merrikh H, Eichberg J. Altered arachidonic acid biosynthesis and antioxidant protection mechanisms in Schwann cells grown in elevated glucose. J Neurochem 2002; 81:1253-62. [PMID: 12068073 DOI: 10.1046/j.1471-4159.2002.00912.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In cultured Schwann cells, elevated glucose induces alterations in arachidonic acid metabolism that cause a decrease in the content of glycerophospholipid arachidonoyl-containing molecular species (ACMS). This could result from decreased de novo arachidonic acid biosynthesis, or increased arachidonic acid release from phospholipids. Incorporation of radioactive 8,11,14-eicosatrienoic acid into ACMS was lower for cells grown in 30 mm versus 5 mm glucose, consistent with a decrease in delta5 desaturase activity. However, neither basal arachidonic acid release from prelabeled cells nor stimulated generation of arachidonic acid in the presence of the reacylation inhibitor, thimerosal, the phosphotyrosine phosphatase inhibitor, bipyridyl peroxovanadium, or both together, were altered by varying the glucose concentrations, indicating that arachidonic acid turnover did not contribute to ACMS depletion. Free cytosolic NAD+ /NADH decreased, whereas NADP+ /NADPH remained unchanged for cells grown in elevated glucose, implying that decreased desaturase activity is a result of metabolic changes other than cofactor availability. Schwann cells in elevated glucose were susceptible to oxidative stress, as shown by increased malondialdehyde, depleted glutathione levels, and reduced cytosolic superoxide dismutase activity. Glutathione-altering compounds had no effect on ACMS levels, in contrast to N -acetylcysteine and alpha-lipoic acid, which partly corrected ACMS depletion in phosphatidylcholine. These findings suggest that in the Schwann cell cultures, a high glucose level elicits oxidative stress and weakens antioxidant protection mechanisms which could decrease arachidonic acid biosynthesis and that this deficit can be partly corrected by treatment with exogenous antioxidants.
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Affiliation(s)
- Cristinel Mîinea
- Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204, USA
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31
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Abstract
1. Modulation of K+ channel activities by cellular oxidative stress has emerged as a significant determinant of vasomotor function in multiple disease states. 2. Evidence from in vitro and in vivo studies suggest that superoxide (O2-) and hydrogen peroxide (H2O2) enhance BKCa channel activity in rat and cat cerebral arterioles; however, activity is decreased by peroxynitrite (ONOO-) in rat cerebral arteries. The mechanisms of changes in BKCa channel properties are not fully understood and may involve oxidation of cysteine residues that are located in the cell membranes. 3. Studies further suggest that O2- increases KATP channel activity in guinea-pig cardiac myocytes, but decreases opening in cerebral vasculature. Both H2O2 and ONOO- enhance KATP channel activity in the myocardium and in coronary, renal, mesenteric and cerebral vascular beds. Alteration of KATP channels by free radicals may be due to oxidation of SH groups or changes in the cytosolic concentration of ATP. 4. It does appear that O2- produced by either reaction of xanthine and xanthine oxidase or elevated levels of glucose reduces Kv channel activity and the impairments can be partially restored by free radical scavengers, superoxide dismutase and catalase. 5. Thus, redox modulation of potassium channel activity is an important mechanism regulating cell vascular smooth muscle membrane potential.
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Affiliation(s)
- Yanping Liu
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
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32
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Nagashima T, Oikawa S, Hirayama Y, Tokita Y, Sekikawa A, Ishigaki Y, Yamada R, Miyazawa T. Increase of serum phosphatidylcholine hydroperoxide dependent on glycemic control in type 2 diabetic patients. Diabetes Res Clin Pract 2002; 56:19-25. [PMID: 11879717 DOI: 10.1016/s0168-8227(01)00353-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In order to clarify the relationship between serum phosphatidylcholine hydroperoxide (PCOOH) levels and blood glucose control in type 2 diabetes patients (DM), DM (n = 61) and normal control (n = 11) were enrolled. High-density lipoprotein (HDL) was separated from serum by the addition of sodium phosphotungstate and magnesium chloride, and the precipitated fraction was prepared as non-HDL. Phospholipids were extracted from whole serum, non-HDL and HDL to estimate PCOOH level with chemiluminescence high performance liquid chromatography (CL-HPLC). PCOOH level (nmol/l, mean +/- S.D.) was higher in DM than in control (33.1 +/- 9.5 vs. 23.0 +/- 8.2 for serum; P < 0.01, 17.0 +/- 5.5 vs. 10.6 +/- 3.8 for non-HDL; P < 0.01, and 16.1 +/- 6.3 vs. 12.3 +/- 5.5 for HDL; not significant, respectively). DM was divided into five groups according to hemoglobin A(1c) (HbA(1c)) levels (%): (1) less than 6, (2) 6-6.4, (3) 6.5-6.9 (4) 7.0-7.4, and (5) over than 7.5. Increase of PCOOH levels was dependent on HbA(1c). We concluded that (1) serum and non-HDL PCOOH increased in DM, (2) the level was strongly correlated with diabetic control, and (3) approximately a half amount of serum PCOOH was present in HDL of both control and DM.
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Affiliation(s)
- Tazuko Nagashima
- CL Research Laboratory, Tohoku Electronic Industrial Co., Ltd., Sendai, Japan
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33
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Catherwood MA, Powell LA, Anderson P, McMaster D, Sharpe PC, Trimble ER. Glucose-induced oxidative stress in mesangial cells. Kidney Int 2002; 61:599-608. [PMID: 11849402 DOI: 10.1046/j.1523-1755.2002.00168.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Hyperglycemia is a well-recognized pathogenic factor of long-term complications in diabetes mellitus. Hyperglycemia not only generates reactive oxygen species but also attenuates antioxidant mechanisms creating a state of oxidative stress. METHODS Porcine mesangial cells were cultured in high glucose (HG) for ten days to investigate the effects on the antioxidant defenses of the cell. RESULTS Mesangial cells cultured in HG conditions had significantly reduced levels of glutathione (GSH) compared with those grown in normal glucose (NG). The reduced GSH levels were accompanied by decreased gene expression of both subunits of gamma-glutamylcysteine synthetase (gamma-GCS), the rate-limiting enzyme in de novo synthesis of GSH. Elevated levels of intracellular malondialdehyde (MDA) were found in cells exposed to HG conditions. HG also caused elevated mRNA levels of the antioxidant enzymes CuZn superoxide dismutase (SOD) and MnSOD. These changes were accompanied by increased mRNA levels of extracellular matrix proteins (ECM), fibronectin (FN) and collagen IV (CIV). Addition of antioxidants to high glucose caused a significant reversal of FN and CIV gene expression; alpha-lipoic acid also up-regulated gamma-GCS gene expression and restored intracellular GSH and MDA levels. CONCLUSIONS The results demonstrate the existence of glucose-induced oxidative stress in mesangial cells as evidenced by elevated MDA and decreased GSH levels. The decreased levels of GSH are as a result of decreased mRNA expression of gamma-GCS within the cell. Antioxidants caused a significant reversal of FN and CIV gene expression, suggesting an etiological link between oxidative stress and increased ECM protein synthesis.
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Affiliation(s)
- Mark A Catherwood
- Department of Clinical Biochemistry, Queen's University of Belfast, Royal Group of Hospitals, Belfast, United Kingdom.
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34
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Schnackenberg CG. Physiological and pathophysiological roles of oxygen radicals in the renal microvasculature. Am J Physiol Regul Integr Comp Physiol 2002; 282:R335-42. [PMID: 11792641 DOI: 10.1152/ajpregu.00605.2001] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The renal microvasculature is an important component in the regulation of kidney function. Recent studies suggest that oxygen radicals can contribute to the modulation of renal cortical and medullary microvascular function under normal conditions as well as in pathophysiological conditions such as diabetes mellitus and hypertension. This review focuses on studies that indicate oxygen radicals can cause renal vasoconstriction, mediate the vasoconstriction of other agonists, and modulate nitric oxide-dependent actions in the normal kidney. Hypertension and diabetes mellitus are associated with oxidative stress. Recent investigations suggest that oxygen radicals may contribute to the enhanced renal vascular tone, increased sensitivity to vasoconstrictors, impaired endothelium-dependent vasodilation, and enhanced tubuloglomerular feedback found in these pathophysiological conditions.
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35
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Gumieniczek A, Hopkała H, Wójtowicz Z, Nieradko M. Differences in antioxidant status in skeletal muscle tissue in experimental diabetes. Clin Chim Acta 2001; 314:39-45. [PMID: 11718677 DOI: 10.1016/s0009-8981(01)00680-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND It has been suggested that oxidative stress may play an important role in pathogenesis of diabetic complications. The present study was designed to evaluate the oxidative stress-related parameters in alloxan (A)-induced long-term diabetes in rabbits. METHODS After 3, 6 and 12 weeks of diabetes, activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R) and concentrations of ascorbic acid (AA) and free sulfhydryl compounds (SH) were measured in skeletal muscle of diabetic rabbits and the normal control subjects. The products of lipid peroxidation (MDA) were also estimated. RESULTS In our tests, the muscle SOD activity, SH and AA concentrations were significantly reduced. CAT activity increased significantly at all time intervals. GSH-Px activity decreased after 3 weeks and then remained at the control level. GSSG-R activity decreased progressively at 3rd and 6th week and then significantly increased. MDA level increased initially, dropped below baseline after 6 weeks and then remained at the level of the control group. CONCLUSIONS The changes observed in the present experiment suggest a significant imbalance in antioxidative system in the skeletal muscle of rabbits with alloxan-induced diabetes. Such study may lead to therapeutic approaches for limiting the damage from oxidation reactions and preventing the diabetic complications.
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Affiliation(s)
- A Gumieniczek
- Department of Medicinal Chemistry, Medical University of Lublin, Chodzki Str. 6, 20-093 Lublin, Poland.
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36
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Powell LA, Nally SM, McMaster D, Catherwood MA, Trimble ER. Restoration of glutathione levels in vascular smooth muscle cells exposed to high glucose conditions. Free Radic Biol Med 2001; 31:1149-55. [PMID: 11705692 DOI: 10.1016/s0891-5849(01)00648-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Hyperglycemia-induced oxidative stress may play a key role in the pathogenesis of diabetic vascular disease. The purpose of this study was to determine the effects of glucose on levels of glutathione (a major intracellular antioxidant), the expression of gamma-glutamylcysteine synthetase (the rate-limiting enzyme in glutathione de novo synthesis), and DNA damage in human vascular smooth muscle cells in vitro. High glucose conditions and buthionine sulphoximine, an inhibitor of gamma-glutamylcysteine synthetase, reduced intracellular glutathione levels in vascular smooth muscle cells. This reduction was accompanied by a decrease in the mRNA expression of both subunits of gamma-glutamylcysteine synthetase as well as an increase in DNA damage. In high glucose conditions, incubation of the vascular smooth muscle cells with alpha-lipoic acid and L-cystine restored glutathione levels. We suggest that the decrease in GSH levels seen in high glucose conditions is mediated by the availability of cysteine (rate-limiting substrate in de novo glutathione synthesis) and the gene expression of the gamma-glutamylcysteine synthetase enzyme. Glutathione depletion is associated with an increase in DNA damage, which can be reduced when glutathione levels are restored.
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Affiliation(s)
- L A Powell
- Department of Clinical Biochemistry, The Royal Group of Hospitals, Belfast, UK.
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37
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Gökkusu C, Palanduz S, Ademoğlu E, Tamer S. Oxidant and antioxidant systems in niddm patients: influence of vitamin E supplementation. Endocr Res 2001; 27:377-86. [PMID: 11678585 DOI: 10.1081/erc-100106015] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Free radical-mediated oxidative stress has been implicated in adverse tissue changes in a number of diseases. In view of the role of oxidative processes in non-insulin dependent diabetes mellitus (NIDDM), in this study, we investigated the oxidant and antioxidant status of plasma in patients with NIDDM and the effect of vitamin E (800 lU/day) supplementation on oxidative stress, antioxidant defense system, fructosamine levels and insulin action. Thirty controls and 40 NIDDM patients were studied. In controls and patients, plasma lipids, vitamin E, lipid peroxide, total thiols (t-SH), superoxide peroxidase (SOD) and glutathione peroxidase (GPx) were measured in the basal state and after vitamin E (800 IU/d) supplementation for a month. All lipids and lipid fractions in plasma were significantly decreased, whereas the HDL-C level was changed in diabetic patients supplemented with vitamin E when compared with baseline values. Vitamin E administration also significantly reduced fasting glucose and fructosamine levels, whereas increased significantly reduced fasting glucose and fructosamine levels, whereas increased significantly plasma C-peptide and insulin levels (p < 0.01, p < 0.001, respectively). Following vitamin E supplementation, TBARs levels were found to be significantly lower (p < 0.001) than the baseline value NIDDM patients are. On the other hand, activities of GPx and SOD were significantly higher (p < 0.001) than baseline values. A similar trend was observed for total thiols contents, but in this case, the increase was not significant. In conclusion, this study demonstrates that vitamin E improved beta-cell function and increased plasma insulin and C-peptide levels, possibly by inducing the antioxidant capacity of the organism and/or reducing the peripheral resistance in NIDDM. Long-term studies are needed to demonstrate the beneficial effects of vitamin E on treatment/prevention of NIDDM.
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Affiliation(s)
- C Gökkusu
- Department of Biochemistry, Istanbul Faculty of Medicine, University of Istanbul, Capa, Turkey.
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38
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Zanetti M, Sato J, Katusic ZS, O'Brien T. Gene transfer of superoxide dismutase isoforms reverses endothelial dysfunction in diabetic rabbit aorta. Am J Physiol Heart Circ Physiol 2001; 280:H2516-23. [PMID: 11356606 DOI: 10.1152/ajpheart.2001.280.6.h2516] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Increased production of oxygen free radicals is an important mechanism of endothelial dysfunction in diabetes mellitus. Our goal was to test whether adenovirus (Ad)-mediated gene transfer of copper/zinc (CuZn) or manganese superoxide dismutase (Mn SOD) improves relaxation of diabetic vessels. The aortas from 9 alloxan-induced diabetic mellitus (DM) and 16 control rabbits were used. Control and DM rings were transduced ex vivo with Ad vectors encoding Mn SOD (AdMn SOD), CuZn SOD (AdCuZn SOD), β-galactosidase (Adβgal), or diluents. In the absence of gene transfer, SOD activity was significantly increased in DM aortas. Transgene expression in DM AdCuZn SOD and DM AdMn SOD-transduced vessels was confirmed by Western blot analysis and by increased SOD activity (DM AdCuZn SOD, 76.2 ± 9.3; DM AdMn SOD, 65.2 ± 4.8; P < 0.05 vs. DM Adβgal; 50.9 ± 4.4 U/mg protein). Superoxide production was increased in DM Adβgal-transduced aorta and relaxations to acetylcholine were impaired in these vessels. Gene transfer of CuZn SOD and Mn SOD corrected both of these defects. Thus Ad-mediated gene transfer CuZn and Mn SOD to the diabetic aorta improves endothelium-dependent relaxation.
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MESH Headings
- Acetylcholine/pharmacology
- Adenoviridae/genetics
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiopathology
- Blotting, Western
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/physiopathology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Enzyme Activation/drug effects
- Enzyme Activation/genetics
- Gene Expression
- Gene Transfer Techniques
- Genes, Reporter
- In Vitro Techniques
- Isoenzymes/administration & dosage
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Male
- Nitric Oxide Donors/pharmacology
- Rabbits
- Superoxide Dismutase/administration & dosage
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Superoxides/metabolism
- Transduction, Genetic
- Transgenes
- Vasodilation/drug effects
- Vasodilator Agents/pharmacology
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Affiliation(s)
- M Zanetti
- Department of Endocrinology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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39
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Beisswenger PJ, Howell SK, O'Dell RM, Wood ME, Touchette AD, Szwergold BS. alpha-Dicarbonyls increase in the postprandial period and reflect the degree of hyperglycemia. Diabetes Care 2001; 24:726-32. [PMID: 11315838 DOI: 10.2337/diacare.24.4.726] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Chronic hyperglycemia is known to increase tissue glycation and diabetic complications, but controversy exists regarding the independent role of increased postprandial glucose excursions. To address this question, we have studied the effect of postprandial glycemic excursions (PPGEs) on levels of methylglyoxal (MG) and 3-deoxyglucosone (3-DG), two highly reactive precursors of advanced glycation end products (AGEs). RESEARCH DESIGN AND METHODS We performed 4-month crossover studies on 21 subjects with type 1 diabetes and compared the effect of premeal insulin lispro or regular insulin on PPGEs and MG/3-DG excursions. PPGE was determined after standard test meal (STMs) and by frequent postprandial glucose monitoring. HbA1c and postprandial MG and D-lactate were measured by HPLC, whereas 3-DG was determined by gas chromatography/mass spectroscopy. RESULTS Treatment with insulin lispro resulted in a highly significant reduction in PPGEs relative to the regular insulin-treated group (P = 0.0005). However, HbA1c levels were similar in the two groups, and no relationship was observed between HbA1c and PPGE (P = 0.93). Significant postprandial increases in MG, 3-DG, and D-lactate occurred after the STM. Excursions of MG and 3-DG were highly correlated with levels of PPGE (R = 0.55, P = 0.0002 and R = 0.61, P = 0.0004; respectively), whereas a significant inverse relationship was seen between PPGE and D-lactate excursions (R = 0.40, P = 0.01). Conversely, no correlation was observed between HbAlc and postprandial MG, 3-DG, or D-lactate levels. CONCLUSIONS Increased production of MG and 3-DG occur with greater PPGE, whereas HbA1c does not reflect these differences. Reduced PPGE also leads to increased production of D-lactate, indicating a role for increased detoxification in reducing MG levels. The higher postprandial levels of MG and 3-DG observed with greater PPGE may provide a partial explanation for the adverse effects of glycemic lability and support the value of agents that reduce glucose excursions.
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Affiliation(s)
- P J Beisswenger
- Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA.
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40
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Doi K, Sawada F, Toda G, Yamachika S, Seto S, Urata Y, Ihara Y, Sakata N, Taniguchi N, Kondo T, Yano K. Alteration of antioxidants during the progression of heart disease in streptozotocin-induced diabetic rats. Free Radic Res 2001; 34:251-61. [PMID: 11264900 DOI: 10.1080/10715760100300231] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Involvement of oxidative stress is implicated in the progression of complication of diabetes mellitus. With respect to heart diseases, we have studied role of oxidative stress/antioxidants using rats treated with streptozotocin to induce diabetes (DM). Hemodynamic and echocardiographic measurements showed thickening of the wall and an increase in the internal dimension of the left ventricle (LV) in DM rats at 8th week. Decrease in diastolic posterior wall velocity and rate of LV pressure change, and increase in LV end diastolic pressures also proved cardiac dysfunction. These changes were further developed in DM rats after 12 weeks. Utilizing rat hearts at 8th and 12th weeks, the following estimations were performed. There was a decrease in the activity of Mn-superoxide dismutase (SOD), suggesting abnormal mitochondrial metabolism of reactive oxygen species. The level of glutathione (GSH) decreased concomitant with a decrease in the expression of gamma-glutamylcysteine synthetase (gamma-GCS). The expression of transforming growth factor-beta1 (TGF-beta1), known as a growth factor and a suppressor of GSH synthesis, elevated in DM rat hearts. Immunohistochemical estimation showed an increase in type IV collagen in DM hearts. Collectively, it was suggested a linkage between mitochondrial damage to generate reactive oxygen species and inactivation of Mn-SOD and elevation of the expression of TGF-beta1 to lead suppression of GSH synthesis and induction of fibrous change for the consequent cardiac dysfunction in DM.
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Affiliation(s)
- K Doi
- Third Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki 852-8501, Japan
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41
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Chakrabarti S, Cukiernik M, Mukherjee S, Chen S. Therapeutic potential of endothelin receptor antagonists in diabetes. Expert Opin Investig Drugs 2000; 9:2873-88. [PMID: 11093358 DOI: 10.1517/13543784.9.12.2873] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Endothelins (ETs) are widely distributed in the body and perform several vascular and non-vascular functions. Experimental evidence indicates that abnormalities of the ET system occur in several organs affected in chronic diabetic complications. Furthermore, ET antagonists were found to prevent structural and functional changes in the target organs of chronic diabetic complications in animal models. Abnormalities of plasma ET levels have also been demonstrated in human diabetes. This review discusses the role of ET in the pathogenesis of chronic diabetic complications. The current experimental evidence suggests that ET antagonism may potentially represent an adjuvant therapeutic tool in the treatment of chronic diabetic complications.
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Affiliation(s)
- S Chakrabarti
- Department of Pathology, DSB 4011, The University of Western Ontario, London, Ontario, Canada.
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42
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Chakrabarti S, Cukiernik M, Hileeto D, Evans T, Chen S. Role of vasoactive factors in the pathogenesis of early changes in diabetic retinopathy. Diabetes Metab Res Rev 2000; 16:393-407. [PMID: 11114100 DOI: 10.1002/1520-7560(0000)9999:9999<::aid-dmrr157>3.0.co;2-g] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Several interactive and mutually perpetuating abnormal biochemical pathways, such as protein kinase C (PKC) activation, augmented polyol pathway, and non-enzymatic glycation, may be activated as a result of sustained hyperglycemia in diabetes. These abnormal pathways may in turn influence several vasoactive factors, which are probably instrumental in the production of functional and morphological changes in the retina in diabetes. The vasoactive factors such as endothelins, nitric oxide, vascular endothelial growth factors, etc., are of importance in mediating functional and structural alterations in early diabetic retinopathy. Intricate and interactive regulatory mechanism(s) among these factors may control ultimate availability of these molecules to produce biologically significant effects. A better understanding of these factors and their interactions would aid the development of adjuvant therapies for the treatment of diabetic retinopathy.
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Affiliation(s)
- S Chakrabarti
- Department of Pathology, University of Western Ontario, London, Ontario, Canada.
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43
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Keegan A, Jack AM, Cotter MA, Cameron NE. Effects of aldose reductase inhibition on responses of the corpus cavernosum and mesenteric vascular bed of diabetic rats. J Cardiovasc Pharmacol 2000; 35:606-13. [PMID: 10774792 DOI: 10.1097/00005344-200004000-00014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We examined the effects of 2 months of streptozotocin-induced diabetes mellitus in rats on relaxation and contraction of corpus cavernosum and the mesenteric vascular bed in vitro. A further diabetic group was treated from diabetes induction with 10 mg/kg/day of the aldose reductase inhibitor, WAY121509. For corpus cavernosum, maximal acetylcholine-induced relaxation was 35.5% reduced (p < 0.001) by diabetes, and this deficit was completely prevented by WAY121509 treatment. Neither diabetes nor treatment affected contractile responses to field stimulation of noradrenergic nerves; however, nonadrenergic noncholinergic nerve relaxation responses were 32.9% decreased by diabetes and WAY 121509 attenuated this by 84% (p < 0.001). For the mesenteric vascular bed, diabetes depressed maximal endothelium-dependent vasodilation to acetylcholine by 25.2% (p < 0.001), and this was partially (50.6%; p < 0.01) prevented by WAY121509. Nitric oxide synthase blockade revealed endothelium-derived hyperpolarising factor-mediated vasodilation to acetylcholine that was 73.5% (p < 0.001) depressed by diabetes; WAY121509 provided partial (43.4%; p < 0.001) protection. Neither diabetes nor treatment affected endothelium-independent vasorelaxation to the nitric oxide donor, sodium nitroprusside, in corpus cavernosum or mesenteric vessels. Thus the data show protective effects of WAY121509 on nitric oxide-mediated cavernosal vasorelaxation responses and on mesenteric endothelium-derived hyperpolarising factor responses. Together these findings could account for the beneficial effects of aldose reductase inhibition on diabetic complications in experimental models.
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Affiliation(s)
- A Keegan
- Department of Biomedical Sciences, University of Aberdeen, Scotland
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44
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45
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Urata Y, Honma S, Goto S, Todoroki S, Iida T, Cho S, Honma K, Kondo T. Melatonin induces gamma-glutamylcysteine synthetase mediated by activator protein-1 in human vascular endothelial cells. Free Radic Biol Med 1999; 27:838-47. [PMID: 10515588 DOI: 10.1016/s0891-5849(99)00131-8] [Citation(s) in RCA: 258] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In the present study, we show that melatonin induces the expression of gamma-glutamylcysteine synthetase (gamma-GCS), the rate-limiting enzyme of glutathione (GSH) synthesis, in ECV304 human vascular endothelial cells. One micromolar melatonin induced the expression of gamma-GCS mRNA followed by an increase in the concentration of GSH with a peak at 24 h. An electrophoretic mobility shift assay showed that melatonin stimulates the DNA-binding activity of activator protein-1 (AP-1) as well as retinoid Z receptor/retinoid receptor-related orphan receptor alpha (RZR/RORalpha). ECV304 cells transiently transfected with a plasmid containing the gamma-GCS promoter-luciferase construct showed increased luciferase activity when treated with melatonin. The melatonin-dependent luciferase activity was found in the gamma-GCS promoter containing AP-1 site. The luciferase activity mediated by AP-1 was repressed in the promoter containing RZR/RORalpha site. In addition, cell cycle analysis showed that melatonin increases the number of cells in the G0/G1 phase; however, treatment of the cells with buthionine sulfoximine, a specific inhibitor of gamma-GCS, abolished the effect of melatonin on the cell cycle, suggesting induction of cell arrest by melatonin requires GSH. As conclusion, induction of GSH synthesis by melatonin protects cells against oxidative stress and regulates cell proliferation.
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MESH Headings
- Buthionine Sulfoximine/pharmacology
- Cell Cycle/drug effects
- Cell Line
- DNA-Binding Proteins/analysis
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation, Enzymologic/drug effects
- Genes, Reporter
- Glutamate-Cysteine Ligase/genetics
- Glutamate-Cysteine Ligase/metabolism
- Glutathione/biosynthesis
- Glutathione/metabolism
- Humans
- Melatonin/pharmacology
- Nuclear Receptor Subfamily 1, Group F, Member 1
- Oxidative Stress/drug effects
- Promoter Regions, Genetic
- RNA, Messenger/metabolism
- Receptors, Cell Surface
- Receptors, Cytoplasmic and Nuclear
- Receptors, Melatonin
- Receptors, Retinoic Acid
- Trans-Activators
- Transcription Factor AP-1/metabolism
- Transfection
- tert-Butylhydroperoxide/pharmacology
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Affiliation(s)
- Y Urata
- Department of Biochemistry and Molecular Biology in Disease, Atomic Bomb Disease Institute, Nagasaki University School of Medicine, Japan
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Szaleczky E, Prechl J, Fehér J, Somogyi A. Alterations in enzymatic antioxidant defence in diabetes mellitus--a rational approach. Postgrad Med J 1999; 75:13-7. [PMID: 10396580 PMCID: PMC1741099 DOI: 10.1136/pgmj.75.879.13] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Defence against the reactive oxidants produced during aerobic metabolism is a complex process and is provided by a system of enzymes and antioxidant compounds capable of preventing excess radical production, neutralising free radicals and repairing the damage caused by them. Regulation of the antioxidant system must provide sufficient, properly located, antioxidant compounds and enzymes. Damage to this system has been proved to play a role in various disorders. Long-term complications of diabetes mellitus are supposed to be partially mediated by oxidative stress. The authors summarise experimental and clinical investigations in this field and analyse the possible importance of the changes in the antioxidant system in the development of diabetic vascular complications.
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Affiliation(s)
- E Szaleczky
- 2nd Department of Medicine, Semmelweis University of Medicine, Budapest, Hungary
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Kijima H, Tsuchida T, Kondo H, Iida T, Oshika Y, Nakamura M, Scanlon KJ, Kondo T, Tamaoki N. Hammerhead ribozymes against gamma-glutamylcysteine synthetase mRNA down-regulate intracellular glutathione concentration of mouse islet cells. Biochem Biophys Res Commun 1998; 247:697-703. [PMID: 9647756 DOI: 10.1006/bbrc.1998.8878] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
gamma-Glutamylcysteine synthetase (gamma-GCS) is a key enzyme in glutathione synthesis and is thought to play a significant role in intracellular detoxification systems. To specifically suppress gamma-GCS gene expression, we constructed two different hammerhead ribozymes against gamma-GCS mRNA transcripts. Two cleavage sites were targeted as follows: site 1 for anti-gamma-GCS ribozyme (H), a GUU triplet located from +348 to +350 of the gamma-GCS heavy chain, and site 2 for anti-gamma-GCS ribozyme (L), a GUU triplet located from +235 to +237 of the gamma-GCS light chain. The anti-gamma-GCS ribozymes effectively cleaved gamma-GCS mRNA in a cell-free system. When transfected into a Min-6 mouse islet cell line, these anti-gamma-GCS ribozymes not only suppressed gamma-GCS gene expression, but also reduced intracellular glutathione concentration. These results suggest that the ribozyme-mediated down-regulation of gamma-GCS gene expression may be useful for analyzing the glutathione-associated cellular defense systems of pancreatic islet cells.
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Affiliation(s)
- H Kijima
- Department of Pathology, Tokai University School of Medicine, Isehara, Japan.
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48
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Fujiwara Y, Nishihara H, Nakakoshi T, Hasegawa T, Tagami S, Kawakami Y. Elevation of plasma lipid peroxides in non-insulin dependent diabetics with multiple lacunar infarcts. J Atheroscler Thromb 1998; 4:90-5. [PMID: 9638520 DOI: 10.5551/jat1994.4.90] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Our purpose was to determine whether lipid peroxides are elevated in the plasma of patients with non-insulin dependent diabetes with multiple lacunar infarcts as detected by magnetic resonance imaging (MRI), and to confirm whether peroxide levels correlate with glycemic controls and blood lipid levels. The level of lipid peroxide (measured as thiobarbituric acid reactive substances (TBARS)) was measured in 23 healthy controls and 28 diabetics showing normal MRI findings and 22 diabetics with multiple lacunar infarcts. These groups were age-matched. In patients with multiple lacunar infarcts, systolic blood pressure, diastolic blood pressure and TBARS levels were significantly higher than in diabetics without such infarcts (p < 0.05). When the diabetic patients were divided into two groups according to the presence or absence of hypertriglyceridemia or hyperglycemia, in both groups plasma TBARS levels in patients with multiple lacunar infarcts were significantly higher than in patients without such infarcts. Multivariate analysis showed systolic blood pressure and plasma TBARS levels to be independent predictors of multiple lacunar infarcts. Among diabetics, total plasma TBARS levels were positively correlated with fasting blood glucose, HbA1c and triglyceride levels, but not with total cholesterol levels and age. In conclusion plasma lipid peroxides were elevated in diabetics with multiple lacunar lesions, and are related to the metabolic imbalance of plasma glucose and lipids.
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Affiliation(s)
- Y Fujiwara
- Department of Internal Medicine, Bibai Rosai Hospital, Hokkaido, Japan
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Iwanaga M, Mori K, Iida T, Urata Y, Matsuo T, Yasunaga A, Shibata S, Kondo T. Nuclear factor kappa B dependent induction of gamma glutamylcysteine synthetase by ionizing radiation in T98G human glioblastoma cells. Free Radic Biol Med 1998; 24:1256-68. [PMID: 9626582 DOI: 10.1016/s0891-5849(97)00443-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Glioblastoma is one of the most malignant of all neoplasms, and often shows resistance to chemotherapy and radiation therapy. Ionizing radiation activates transcriptional factors, such as nuclear factor kappa-B (NF-kappa B). Previously we found that glutathione (GSH) synthesis is induced by cytokines mediated by NF-kappa B (Urata et al. J. Biol. Chem., 1996). Here, we present direct evidence that NF-kappa B activated by ionizing radiation induces the expression of gamma-glutamylcysteine synthetase (gamma-GCS), the rate limiting enzyme of GSH synthesis, using T98G human glioblastoma cells. T98G cells have approximately 14-times the level of intracellular GSH of NB9 cells, radiation-sensitive neuroblastoma cells. In T98G cells, 30-Gy of ionizing radiation was required for the activation of NF-kappa B on an electrophoretic mobility shift assay and the induction of gamma-GCS mRNA on Northern blots and a nuclear run-on assay. However, when T98G cells were treated with buthionine sulfoximine, 3-Gy of ionizing radiation stimulated the DNA-binding activity of NF-kappa B and the expression of gamma-GCS. We constructed chimeric genes containing various regions of gamma-GCS promoter gene and the coding region for Luciferase. T98G cells transiently transfected with a plasmid containing the gamma-GCS promoter-luciferase construct showed increased luciferase activity when treated with ionizing radiation. The luciferase activity stimulated by ionizing radiation was found in the gamma-GCS promoter containing the NF-kappa B binding site, whereas not in that containing its mutated site. These results suggest that GSH synthesis is upregulated by ionizing radiation mediated by NF-kappa B and a high concentration of GSH in T98G cells causes downregulation of the NF-kappa B-DNA binding activity in response to ionizing radiation. The irresponsiveness of the intracellular signal transduction cascade to irradiation may be a factor in the resistance of T98G cells to radiation therapy.
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Affiliation(s)
- M Iwanaga
- Department of Neurosurgery, Nagasaki University School of Medicine, Japan
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50
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Mehta A, Singh S, Ganguly NK. Role of reactive oxygen species in Salmonella typhimurium-induced enterocyte damage. Scand J Gastroenterol 1998; 33:406-14. [PMID: 9605263 DOI: 10.1080/00365529850171044] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Reactive oxygen species (ROS) are potent mediators of inflammatory cell-mediated tissue destruction and may be of pathophysiologic importance in Salmonella typhimurium-induced tissue damage. METHODS In this study the ligated rat ileal loops were injected with Salmonella live culture or toxin. The ROS generation was detected by measuring the mucosal myeloperoxidase (MPO) activity; the enterocyte xanthine oxidase (XO) activity, and the chemiluminescence response of gut macrophages. The enterocyte damage was estimated by measuring the extent of lipid peroxidation and cell viability. RESULTS Treatment with Salmonella live culture or toxin resulted in an increase in the mucosal MPO activity, the enterocyte XO activity, and the chemiluminescence response of macrophages. Treated loop enterocytes had an increased extent of lipid peroxidation and decreased cell viability. Cell viability was also decreased when the enterocytes were co-cultured with macrophages isolated from the treated loops. Lipid peroxidation decreased, and cell viability increased in the presence of superoxide dismutase (SOD) or catalase. CONCLUSIONS The S. typhimurium-mediated intestinal infection is accompanied by an increased generation of ROS, which may induce the lipid peroxidation of the enterocyte membrane, thereby leading to a loss of cell viability.
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Affiliation(s)
- A Mehta
- Dept. of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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