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Ishii T, Warabi E, Mann GE. Mechanisms underlying Nrf2 nuclear translocation by non-lethal levels of hydrogen peroxide: p38 MAPK-dependent neutral sphingomyelinase2 membrane trafficking and ceramide/PKCζ/CK2 signaling. Free Radic Biol Med 2022; 191:191-202. [PMID: 36064071 DOI: 10.1016/j.freeradbiomed.2022.08.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 12/14/2022]
Abstract
Hydrogen peroxide is an aerobic metabolite playing a central role in redox signaling and oxidative stress. H2O2 could activate redox sensitive transcription factors, such as Nrf2, AP-1 and NF-κB by different manners. In some cells, treatment with non-lethal levels of H2O2 induces rapid activation of Nrf2, which upregulates expression of a set of genes involved in glutathione (GSH) synthesis and defenses against oxidative damage. It depends on two steps, the rapid translational activation of Nrf2 and facilitation of Nrf2 nuclear translocation. We review the molecular mechanisms by which H2O2 induces nuclear translocation of Nrf2 in cultured cells by highlighting the role of neutral sphingomyelinase 2 (nSMase2), a GSH sensor. H2O2 enters cells through aquaporin channels in the plasma membrane and is rapidly reduced to H2O by GSH peroxidases to consume cellular GSH, resulting in nSMase2 activation to generate ceramide. H2O2 also activates p38 MAP kinase, which enhances transfer of nSMase2 from perinuclear regions to plasma membrane lipid rafts to accelerate ceramide generation. Low levels of ceramide activate PKCζ, which then activates casein kinase 2 (CK2). These protein kinases are able to phosphorylate Nrf2 to stabilize and activate it. Notably, Nrf2 also binds to caveolin-1 (Cav1), which protects Nrf2 from Keap1-mediated degradation and limits Nrf2 nuclear translocation. We propose that Cav1serves as a signaling hub for the control of H2O2-mediated phosphorylation of Nrf2 by kinases, which results in release of Nrf2 from Cav1 to facilitate nuclear translocation. In summary, H2O2 induces GSH depletion which is recovered by Nrf2 activation dependent on p38/nSMase2/ceramide signaling.
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Affiliation(s)
- Tetsuro Ishii
- School of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Eiji Warabi
- School of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Giovanni E Mann
- King's British Heart Foundation Centre of Research Excellence, School of Cardiovascular and Metabolic Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK.
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Simon E, Aswini P, Sameer Kumar VB, Mankadath G. Curcumin and its synthetic analogue dimethoxycurcumin differentially modulates antioxidant status of normal human peripheral blood mononuclear cells. Free Radic Res 2018; 52:583-591. [PMID: 29621898 DOI: 10.1080/10715762.2018.1455002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Curcumin is a polyphenol derived from the herb Curcuma longa, which has been extensively studied in terms of its antitumour, antioxidant, and chemopreventive activity as well as various other effects. In the present work we compared curcumin with its synthetic analogue dimethoxycurcumin (dimc) in terms of its antioxidant enzyme-modulating effects in human peripheral blood mononuclear cells (PBMC). We found that these compounds modulate antioxidant enzymes differentially. Both curcumin and dimethoxycurcumin effected a decrease in lipid peroxidation status in PBMC, however, curcumin had better activity in this regard. An increase in the activity of catalase was seen in the case of curcumin-treated PBMC, whereas dimc increased catalase activity significantly to almost twofold level. Real time-polymerase chain reaction (RT-PCR) analysis revealed significant up-regulation of catalase at mRNA level post treatment with curcumin as well as dimc, however, dimc had better activity in this regard. Glutathione reductase (GR) activity and reduced glutathione levels increased in the case of peripheral blood mononuclear cells (PBMC) treated with curcumin, however, the trend was reversed with dimethoxycurcumin where, both glutathione reductase activity and reduced glutathione levels were significantly reduced. RT-PCR analysis of glutathione reductase mRNA levels showed decrease in mRNA levels post treatment with dimethoxycurcumin (dimc) further corroborating GR enzyme assay results, however, we could not obtain significant result post curcumin treatment. NFkB reporter assay and western blot analysis of nuclear as well as cytosolic fractions of NFkB revealed that curcumin inhibits NFkB activation whereas inhibition was much less with dimc. It has been reported that curcumin and dimc exerts differential cytotoxicity in normal and tumour cells and the reason for this had been attributed to the differential uptake of these compounds by normal cells and tumour cells. Based on our results we propose that differential modulation of antioxidant enzymes via NFkB pathway could be the reason behind differential cytotoxicity of dimc as well as curcumin in normal cells and tumour cells in addition to differential uptake of these compounds as reported previously.
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Affiliation(s)
- Emmanuel Simon
- a Department of Life Sciences , University of Calicut , Malappuram , India
| | - P Aswini
- b Department of Biochemistry & Molecular Biology , School of the Biological Sciences, Central University of Kerala , Kasaragod , India
| | - V B Sameer Kumar
- b Department of Biochemistry & Molecular Biology , School of the Biological Sciences, Central University of Kerala , Kasaragod , India
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3
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Galvanic zinc–copper microparticles produce electrical stimulation that reduces the inflammatory and immune responses in skin. Arch Dermatol Res 2011; 303:551-62. [DOI: 10.1007/s00403-011-1145-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 02/16/2011] [Accepted: 02/23/2011] [Indexed: 12/23/2022]
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4
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Wang BJ, Guo YL, Chang HY, Sheu HM, Pan MH, Lee YH, Wang YJ. N-acetylcysteine inhibits chromium hypersensitivity in coadjuvant chromium-sensitized albino guinea pigs by suppressing the effects of reactive oxygen species. Exp Dermatol 2011; 19:e191-200. [PMID: 20113346 DOI: 10.1111/j.1600-0625.2009.01045.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Chromium hypersensitivity is an important issue in occupational skin disease. When hexavalent chromium enters the cell, it can be reduced to trivalent chromium, resulting in the formation of reactive oxygen species (ROS). ROS are considered to play an important role in the progression of allergic contact dermatitis. N-acetylcysteine (NAC) could increase glutathione levels in the skin and act as an antioxidant. AIMS We attempted to demonstrate that NAC could inhibit chromium hypersensitivity in a coadjuvant chromium-sensitized albino guinea pig model by counteracting the formation of ROS. METHODS We utilized a coadjuvant chromium-sensitized albino guinea pig model to evaluate both the severity of the skin reaction by intradermal and epicutaneous elicitation tests and the sensitization rate of chromium hypersensitivity in NAC-treated and NAC-untreated albino guinea pigs (GP). Furthermore, three ROS parameters, including H(2)O(2,) malondialdehyde (MDA) levels in the skin and the oxygen radical absorbance capacity (ORAC) in plasma, were analyzed in NAC-treated and NAC-untreated coadjuvant chromium-sensitized albino GP. RESULTS The severity of the skin reaction in the intradermal and epicutaneous elicitation test significantly diminished when the albino GP were treated with a dose of 1200 mg/kg/day of NAC. This dose also significantly decreased the sensitization rate of chromium hypersensitivity. In addition, treatment with 1200 mg/kg/day of NAC significantly reduced the H(2)O(2) and MDA levels in the skin and significantly increased the ORAC in the plasma of albino GP. Therefore, NAC could be a potential chemopreventative agent to prevent the progression of chromium hypersensitivity.
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Affiliation(s)
- Bour-Jr Wang
- Department of Environmental and Occupational Health, National Cheng Kung University Medical College, Tainan, Taiwan
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5
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Zinellu A, Lepedda A, Sotgia S, Zinellu E, Marongiu G, Usai MF, Gaspa L, De Muro P, Formato M, Deiana L, Carru C. Albumin-bound low molecular weight thiols analysis in plasma and carotid plaques by CE. J Sep Sci 2010; 33:126-31. [PMID: 19950356 DOI: 10.1002/jssc.200900582] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We describe a new method for the quantification of low molecular weight thiols, as homocysteine, cysteine, cysteinylglycine, glutamylcysteine and glutathione bound to human plasma albumin. After albumin isolation and purification by SDS-PAGE, thiols were freed from protein with tri-n-butylphosphine and successively derivatized with 5-iodoacetamidofluorescein. Samples were then injected and quantified in about 18 min by CE with laser induced fluorescence detection. Precision tests indicate a good repeatability of the method both for migration times (RSD<0.63%) and areas (RSD<2.98%). The method allows to measure all five low molecular weight thiols released from just 3 microg of albumin thus improving the other described methods in which only three or four thiols were detected. Due to the elevated sensitivity (LOD of 0.3 pM for all thiols), also low molecular weight thiols bound to albumin filtered in tissues could be quantified.
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Affiliation(s)
- Angelo Zinellu
- Dept. Biomedical Sciences, University of Sassari, Sassari, Italy.
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Zinellu A, Lepedda A, Sotgia S, Zinellu E, Scanu B, Turrini F, Spirito R, Deiana L, Formato M, Carru C. Evaluation of low molecular mass thiols content in carotid atherosclerotic plaques. Clin Biochem 2009; 42:796-801. [PMID: 19233150 DOI: 10.1016/j.clinbiochem.2009.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 02/04/2009] [Accepted: 02/05/2009] [Indexed: 01/02/2023]
Abstract
OBJECTIVES Despite the evidence that both homocysteine and cysteine are important risk factors for vascular disease and atherosclerosis no information are reported about their effective amount in plaque and on the relationship with the other low molecular weight thiols. DESIGN AND METHODS We used capillary electrophoresis to measure thiols in both carotid plaque specimens and plasma samples from 37 patients undergoing carotid endarterectomy. RESULTS Pearson's correlation shows that intraplaque homocysteine, cysteine and cysteinylglycine levels are related to their plasma concentrations. The distribution of intraplaque GSH and Glu-Cys was higher than that of the same thiols in plasma, whereas the other thiols were significantly less prevalent in plaque than in plasma. Intraplaque haemoglobin and GSH levels were correlated, thus suggesting their common origin from erythrocytes lysis. CONCLUSION Data suggest that increased levels of intraplaque glutathione may induce important effects on plaque fate by perturbing the normal LMW thiol redox state.
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Affiliation(s)
- Angelo Zinellu
- Dipartimento di Scienze Biomediche, Università di Sassari, Italy; Istituto Nazionale Biostrutture e Biosistemi, Osilo, Italy.
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7
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Lee MN, Lee SH, Lee MY, Kim YH, Park JH, Ryu JM, Yun SP, Lee YJ, Kim MO, Park K, Han HJ. Effect of dihydrotestosterone on mouse embryonic stem cells exposed to H2O2-induced oxidative stress. J Vet Sci 2008; 9:247-56. [PMID: 18716444 PMCID: PMC2811836 DOI: 10.4142/jvs.2008.9.3.247] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oxidative stresses induced by reactive oxygen species (ROS) have been shown to be involved in several physiological and pathophysiological processes, such as cell proliferation and differentiation. Steroid hormones can protect cells against apoptosis or induce cell proliferation by several mechanisms. Among androgenic hormones, dihydrotestosterone (DHT) is generated by a 5alpha- reduction of testosterone. Unlike testosterone, DHT cannot be aromatized to estradiol, therefore DHT is considered a pure androgenic steroid. This study was conducted to examine the effect of DHT (10(-7) M) on H2O2 (10(-3) M) -induced injuries in mouse embryonic stem (ES) cells. H2O2 induced ROS generation and increased lipid peroxide formation and DNA fragmentation. These effects of H2O2 were inhibited by pretreatment with DHT. H2O2 also increased the phosphorylation of p38 MAPK, SAPK/JNK and nuclear factor kappa B (NF-kappaB), but DHT blocked these effects. Moreover, H2O2 decreased DNA synthesis and the levels of cell cycle regulatory proteins [cyclin D1, cyclin E, cyclin-dependent kinase (CDK) 2, and CDK 4]. These effects of H2O2 were inhibited by pretreatment with DHT. In conclusion, DHT may partially prevent H2O2-induced cell injury through inhibition of ROS and ROS-induced activation of p38 MAPK, SAPK/JNK and NF-kappaB in mouse ES cells.
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Affiliation(s)
- Mi Na Lee
- Department of Urology, Chonnam National University Medical School, Gwangju 501-746, Korea
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Kwon D, Choi K, Choi C, Benveniste EN. Hydrogen peroxide enhances TRAIL-induced cell death through up-regulation of DR5 in human astrocytic cells. Biochem Biophys Res Commun 2008; 372:870-4. [PMID: 18534188 DOI: 10.1016/j.bbrc.2008.05.148] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Accepted: 05/24/2008] [Indexed: 12/01/2022]
Abstract
The central nervous system (CNS) is particularly vulnerable to reactive oxygen species (ROS), which have been implicated in the pathogenesis of various neurological disorders. The TNF superfamily of cytokines, especially tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), induces caspase-dependent cell death and is also implicated in various neurodegenerative diseases. In this study, we investigated the relationship between ROS and TRAIL-induced cell death. Exposure to hydrogen peroxide (H(2)O(2)) (100 microM) sensitized human astrocytic cells to TRAIL-induced cell death (up to 7-fold induction). To delineate the molecular mechanisms responsible for H(2)O(2)-induced sensitization, we examined expression of various genes (Caspase-8, Fas, FasL, DR4, DR5, DcR1, DcR2, TRAIL, TNFRp55) related to TRAIL-induced cell death. Treatment with H(2)O(2) significantly increased DR5 mRNA and protein expression in a time- and dose-dependent manner. H(2)O(2)-mediated cell death was blocked upon treatment with DR5:Fc protein, a TRAIL-specific antagonistic protein. These findings collectively suggest that oxidative stress sensitizes human astroglial cells to TRAIL-induced cell death through up-regulation of DR5 expression.
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Affiliation(s)
- Daeho Kwon
- Medical Research Center for Environmental Toxico-Genomics and Proteomics, Korea University College of Medicine, Anam dong-5ga 126-1, Seongbuk-gu, Seoul 136-705, Republic of Korea.
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Sharma SD, Meeran SM, Katiyar SK. Dietary grape seed proanthocyanidins inhibit UVB-induced oxidative stress and activation of mitogen-activated protein kinases and nuclear factor-κB signaling in in vivo SKH-1 hairless mice. Mol Cancer Ther 2007; 6:995-1005. [PMID: 17363493 DOI: 10.1158/1535-7163.mct-06-0661] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have shown previously that dietary grape seed proanthocyanidins (GSP) inhibit UVB-induced photocarcinogenesis in mice. As UVB-induced oxidative stress and oxidative stress-mediated signaling has been implicated in photocarcinogenesis, this study was designed to investigate the effect of dietary GSPs on UVB-induced oxidative stress in in vivo SKH-1 hairless mice. Here, we report that provision of dietary GSPs (0.2 and 0.5%, w/w) to mice exposed to either acute UVB irradiation (120 mJ/cm(2)) or chronic irradiation of UVB inhibited depletion of glutathione peroxidase, catalase, and glutathione, and inhibited UVB-induced H(2)O(2), lipid peroxidation, protein oxidation, and nitric oxide in mouse skin. As UV-induced oxidative stress mediates activation of mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-kappaB) signaling pathways, we determined the effect of dietary GSPs on these pathways. We observed that dietary GSPs inhibited UVB-induced phosphorylation of extracellular signal-regulated kinase 1/2, c-Jun-NH(2)-kinase, and p38 proteins of MAPK family, which seems to be mediated through reactivation of MAPK phosphatases. GSPs inhibited UVB-induced activation of NF-kappaB/p65 through inhibition of degradation of IkappaBalpha and activation of IkappaB kinase alpha (IKKalpha). As NF-kappaB-targeted genes play critical roles in inflammation and cellular proliferation, we assessed the effect of GSPs on proteins encoded by these genes. Dietary GSPs resulted in inhibition of the expression of proliferating cell nuclear antigen, cyclin D1, inducible nitric oxide synthase, and cyclooxygenase-2 in the skin. Collectively, our data show that GSPs have the ability to protect the skin from the adverse effects of UVB radiation via modulation of the MAPK and NF-kappaB signaling pathways and provide a molecular basis for the photoprotective effects of GSPs in an in vivo animal model.
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Affiliation(s)
- Som D Sharma
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Boulevard, Birmingham, AL 35294, USA
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Katiyar SK, Meeran SM. Obesity increases the risk of UV radiation-induced oxidative stress and activation of MAPK and NF-kappaB signaling. Free Radic Biol Med 2007; 42:299-310. [PMID: 17189835 PMCID: PMC1805635 DOI: 10.1016/j.freeradbiomed.2006.10.049] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2006] [Revised: 10/17/2006] [Accepted: 10/25/2006] [Indexed: 10/24/2022]
Abstract
Obesity has been implicated in several diseases, including cancer; however, the relationship of obesity and susceptibility to ultraviolet (UV) radiation-caused skin diseases has not been investigated. As UV-induced oxidative stress has been implicated in several skin diseases, we assessed the role of obesity on UVB-induced oxidative stress in genetically obese Lep(ob)/Lep(ob) (leptin-deficient) mice. Here, we report that chronic exposure to UVB (120 mJ/cm(2)) resulted in greater oxidative stress in the skin of obese mice in terms of higher levels of H(2)O(2) and NO production, photo-oxidative damage of lipids and proteins, and greater depletion of antioxidant defense enzymes, like glutathione, glutathione peroxidase, and catalase. As UV-induced oxidative stress mediates activation of MAPK and NF-kappaB signaling pathways, we determined the effects of UVB on these pathways in obese mice. Exposure of obese mice to UVB resulted in phosphorylation of ERK1/2, JNK, and p38 proteins of the MAPK family. Compared to wild-type mice, the obese mice exhibited higher levels of phosphorylation of these proteins, greater activation of NF-kappaB/p65, and higher levels of circulating proinflammatory cytokines, including TNF-alpha, IL-1beta and IL-6, on UVB irradiation. Taking these results together, our study suggests for the first time that obesity in mice is associated with greater susceptibility to UVB-induced oxidative stress and therefore may be a risk factor for skin diseases associated with UVB-induced oxidative stress.
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Affiliation(s)
- Santosh K Katiyar
- Department of Dermatology, University of Alabama at Birmingham, P.O. Box 202, Volker Hall 557, 1670 University Boulevard, Birmingham, AL 35294, USA.
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Swennen ELR, Dagnelie PC, Bast A. ATP inhibits hydroxyl radical formation and the inflammatory response of stimulated whole blood even under circumstances of severe oxidative stress. Free Radic Res 2006; 40:53-8. [PMID: 16298759 DOI: 10.1080/10715760500364298] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We recently reported that Adenosine-5'-triphosphate (ATP) is able to inhibit the inflammatory reaction in stimulated whole blood. Many diseases, in which inflammatory reactions are involved, are associated with oxidative stress. In the present study, we therefore, investigated the effect of ATP on cytokine release in stimulated whole blood under conditions of oxidative stress, as simulated by pre-incubation of blood with hydrogen peroxide (H(2)O(2)). In the presence of H(2)O(2), ATP at concentrations of 100 and 300 microM inhibited Tumour Necrosis factor-alpha (TNF-alpha) release and stimulated IL-10 release in LPS-PHA stimulated whole blood. Moreover, electron spin resonance (ESR) measurements showed that ATP and its breakdown product Adenosine-5'-diphosphate (ADP) attenuated spin trap-hydroxyl radical adduct formation in the Fenton reaction. Our results demonstrate that even in circumstances of severe oxidative stress, ATP has marked anti-inflammatory properties in stimulated whole blood. Moreover, the inhibition of the hydroxyl radical ESR signal indicates a direct attenuation of oxidative stress by ATP.
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Affiliation(s)
- Els L R Swennen
- Department of Epidemiology, NUTRIM, Maastricht University, P.O. Box 616 6200 MD, The Netherlands.
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12
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Mantena SK, Katiyar SK. Grape seed proanthocyanidins inhibit UV-radiation-induced oxidative stress and activation of MAPK and NF-kappaB signaling in human epidermal keratinocytes. Free Radic Biol Med 2006; 40:1603-14. [PMID: 16632120 DOI: 10.1016/j.freeradbiomed.2005.12.032] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 12/14/2005] [Accepted: 12/23/2005] [Indexed: 11/20/2022]
Abstract
Solar ultraviolet (UV) radiation-induced oxidative stress has been implicated in various skin diseases. Here, we report the photoprotective effect of grape seed proanthocyanidins (GSPs) on UV-induced oxidative stress and activation of mitogen-activated protein kinase (MAPK) and NF-kappaB signaling pathways using normal human epidermal keratinocytes (NHEK). Treatment of NHEK with GSPs inhibited UVB-induced hydrogen peroxide (H2O2), lipid peroxidation, protein oxidation, and DNA damage in NHEK and scavenged hydroxyl radicals and superoxide anions in a cell-free system. GSPs also inhibited UVB-induced depletion of antioxidant defense components, such as glutathione peroxidase, catalase, superoxide dismutase, and glutathione. As UV-induced oxidative stress mediates activation of MAPK and NF-kappaB signaling pathways, we determined the effects of GSPs on these pathways. Treatment of NHEK with GSPs inhibited UVB-induced phosphorylation of ERK1/2, JNK, and p38 proteins of the MAPK family at the various time points studied. As UV-induced H2O2 plays a major role in activation of MAPK proteins, NHEK were treated with H2O2 with or without GSPs and other known antioxidants, viz. (-)-epigallocatechin-3-gallate, silymarin, ascorbic acid, and N-acetylcysteine. It was observed that H2O2-induced phosphorylation of ERK1/2, JNK, and p38 was decreased by these antioxidants. Under identical conditions, GSPs also inhibited UVB-induced activation of NF-kappaB/p65, which was mediated through inhibition of degradation and activation of IkappaBalpha and IKKalpha, respectively. Together, these results suggest that GSPs could be useful in the attenuation of UV-radiation-induced oxidative stress-mediated skin diseases in human skin.
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Affiliation(s)
- Sudheer K Mantena
- Department of Dermatology, University of Alabama at Birmingham, Volker Hall 557, 1670 University Boulevard, P.O. Box 202, Birmingham, AL 35294, USA
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Carru C, Zinellu A, Sotgia S, Chessa R, Piredda F, Antonietta Casu M, Deiana L, Porcu P. Carotid narrowing degree and plasma thiol levels in carotid endarterectomy patients. Clin Chem Lab Med 2005; 43:1015-9. [PMID: 16197291 DOI: 10.1515/cclm.2005.178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe aim of this work was to study the association between plasma thiol levels and percentage carotid narrowing in a group of 68 patients who underwent a carotid endarterectomy, pertained as a risk factor for vascular and cardiovascular disease. Total plasma thiols were measured by capillary electrophoresis laser-induced fluorescence. The mean values of the hematological parameters studied were within normal limits and 25% of the patients were hyperhomocysteinemic (homocysteine >15μmol/L). Pearson's correlation between carotid narrowing degree and the most common risk factors for atherosclerosis showed a positive relationship only between carotid narrowing degree and cysteine levels (r=0.252; p<0.05). Stepwise multiple linear regression with carotid narrowing degree as the dependent variable, and cysteine, homocysteine, age, triglyceride and low-density lipoprotein-cholesterol as independent variables confirmed that cysteine was significantly associated with these variables. By regrouping the population according to cysteine and homocysteine concentration percentiles, we found positive correlation between these parameters and median values of carotid narrowing degree. Our study provides experimental evidence to confirm that plasma homocysteine and cysteine are involved in carotid narrowing after carotid endarterectomy intervention, suggesting that cysteine may be involved in the deleterious molecular mechanisms active in carotid stenosis.
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Affiliation(s)
- Ciriaco Carru
- Department of Biomedical Sciences, Chair of Clinical Biochemistry, University of Sassari, Sassari, Italy
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Afaq F, Adhami VM, Ahmad N, Mukhtar H. Inhibition of ultraviolet B-mediated activation of nuclear factor kappaB in normal human epidermal keratinocytes by green tea Constituent (-)-epigallocatechin-3-gallate. Oncogene 2003; 22:1035-44. [PMID: 12592390 DOI: 10.1038/sj.onc.1206206] [Citation(s) in RCA: 159] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, possesses significant anti-inflammatory and cancer chemopreventive properties. Studies have shown the photochemopreventive effects of green tea and EGCG in cell culture, animal models, and human skin. The molecular mechanism(s) of photochemopreventive effects of EGCG are incompletely understood. We recently showed that EGCG treatment of the normal human epidermal keratinocytes (NHEK) inhibits ultraviolet (UV)B-mediated activation of the mitogen-activated protein kinase (MAPK) pathway. In this study, we evaluated the effect of EGCG on UVB-mediated modulation of the nuclear factor kappa B (NF-kappaB) pathway, which is known to play a critical role in a variety of physiological functions and is involved in inflammation and development of cancer. Immunoblot analysis demonstrated that the treatment of NHEK with EGCG (10-40 microM) for 24 h resulted in a significant inhibition of UVB (40 mJ/cm(2))-mediated degradation and phosphorylation of IkappaBalpha and activation of IKKalpha, in a dose-dependent manner. UVB-mediated degradation and phosphorylation of IkappaBalpha and activation of IKKalpha was also observed in a time-dependent protocol (15 and 30 min, 1, 2, 3, 6, 12 h post-UVB exposure). Employing immunoblot analysis, enzyme-linked immunosorbent assay, and gel shift assay, we demonstrate that EGCG treatment of the cells resulted in a significant dose- and time-dependent inhibition of UVB-mediated activation and nuclear translocation of a NF-kappaB/p65. Our data suggest that EGCG protects against the adverse effects of UV radiation via modulations in NF-kappaB pathway, and provide a molecular basis for the photochemopreventive effect of EGCG.
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Affiliation(s)
- Farrukh Afaq
- Department of Dermatology, University of Wisconsin, Madison, WI 53706, USA
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Haddad JJ, Fahlman CS. Redox- and oxidant-mediated regulation of interleukin-10: an anti-inflammatory, antioxidant cytokine? Biochem Biophys Res Commun 2002; 297:163-76. [PMID: 12237098 DOI: 10.1016/s0006-291x(02)02094-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Reduction-oxidation (redox) state constitutes such a potential signaling mechanism for the regulation of an inflammatory signal associated with oxidative stress. Interleukin (IL)-10 has recently emerged as an anti-inflammatory cytokine with antioxidant properties. Interestingly, redox- and oxidant-mediated pathways positively and/or negatively regulate the expression, distribution, and functional properties of IL-10, thus, allowing the evolution of what is known as an anti-inflammatory redox-oxidant revolving axis. This axis is directly involved in regulating phosphorylation mechanisms, which eventually control gene expression and the biosynthesis of oxidative stress-related cofactors, such as reactive species and inflammatory cytokines. The association between IL-10, an anti-inflammatory antioxidant, with redox- and oxidant-related pathways governing the regulation of inflammatory and closely dependent processes is thereafter discussed.
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Affiliation(s)
- John J Haddad
- Severinghaus-Radiometer Research Laboratories, Molecular Neuroscience Research Division, Department of Anesthesia and Perioperative Care, University of California at San Francisco, School of Medicine, 94143-0542, USA.
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