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Abstract
The pronounced radiosensitivity of renal tissue limits the total radiotherapeutic dose that can be applied safely to treatment volumes that include the kidneys. The incidence of clinical radiation nephropathy has increased with the use of total-body irradiation (TBI) in preparation for bone marrow transplantation and as a consequence of radionuclide therapies. The clinical presentation is azotemia, hypertension, and, disproportionately, severe anemia seen several months to years after irradiation that, if untreated, leads to renal failure. Structural features include mesangiolysis, sclerosis, tubular atrophy, and tubulointerstitial scarring. Similar changes are seen in a variety of experimental animal models. The classic view of radiation nephropathy being inevitable, progressive, and untreatable because of DNA damage-mediated cell loss at division has been replaced by a new paradigm in which radiation-induced injury involves not only direct cell kill but also involves complex and dynamic interactions between glomerular, tubular, and interstitial cells. These serve both as autocrine and as paracrine, if not endocrine, targets of biologic mediators that mediate nephron injury and repair. The renin angiotensin system (RAS) clearly is involved; multiple experimental studies have shown that antagonism of the RAS is beneficial, even when not initiated until weeks after irradiation. Recent findings suggest a similar benefit in clinical radiation nephropathy.
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Affiliation(s)
- Eric P Cohen
- Medical College of Wisconsin, Milwaukee, WI, USA
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52
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Abstract
Free radicals and damage caused by these molecular species are implicated in the pathogenesis of a variety of diseases, including autoimmune. Here we have examined oxidative damage, SOD activity and autoantibodies against SOD in systemic lupus erythematosus (SLE), a multifactorial disease with autoantibody production as an universal feature. We found significantly increased amounts of conjugated dienes in the SLE patients compared to normals (mean value of 0.917 vs 0.627, p = 0.0001) and MDA formation (6.96 vs 4.17 nmoles/microl, p = 0.0006) as well as decreased SOD activity. In addition, we found autoantibodies binding SOD by both ELISA and immunoblot. The presence of anti-SOD antibodies was associated with increased free radical damage in SLE patients. Heat inactivated anti-SOD autoantibodies were able to inhibit the activity of the enzyme. We propose that the inhibition of SOD by autoantibodies is, in part, responsible for the increased free radical damage seen in the disease.
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Affiliation(s)
- Biji T Kurien
- Arthritis and Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA
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53
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Taysi S, Gul M, Sari RA, Akcay F, Bakan N. Serum oxidant/antioxidant status of patients with systemic lupus erythematosus. Clin Chem Lab Med 2003; 40:684-8. [PMID: 12241014 DOI: 10.1515/cclm.2002.117] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The levels of malondialdehyde and ceruloplasmin, and superoxide dismutase activity were higher, while transferrin concentration and the activities of glutathione peroxidase and catalase were lower in serum of patients with systemic lupus erythematosus (n=24) compared with healthy controls (n=20). Disease activity index correlated positively with serum malondialdehyde level (r=0.47, p<0.05), erythrocyte sedimentation rate (r=0.41, p<0.05) and C-reactive protein concentration (r=0.41, p<0.05), while it correlated negatively with serum superoxide dismutase (r=0.42, p<0.05) and glutathione peroxidase (r=-0.44, p<0.05) activities in patients. No such correlations were found in healthy control subjects. It remains to be seen whether correlations found between disease activity score and serum malondialdehyde level, and also activities of serum superoxide dismutase and glutathione peroxidase enzymes observed in the present study may be used to predict prognosis in patients with systemic lupus erythematosus.
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Affiliation(s)
- Seyithan Taysi
- Department of Biochemistry, Faculty of Medicine, Ataturk University, Erzurum, Turkey.
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54
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Kamireddy R, Kavuri S, Devi S, Vemula H, Chandana D, Harinarayanan S, James R, Rao A. Oxidative stress in pediatric nephrotic syndrome. Clin Chim Acta 2002; 325:147-50. [PMID: 12367779 DOI: 10.1016/s0009-8981(02)00294-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Nephrotic syndrome (NS) is a stressful condition for children where oxidative damage would also influence the response of these patients to therapy. METHODS The present study was conducted in children with nephrotic syndrome during relapse and remission and in 10 age- and sex-matched healthy volunteers. Red cell glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) concentrations as well as plasma ceruloplasmin (CP) and vitamin E concentrations were analyzed in controls and in patients. RESULTS Erythrocyte superoxide dismutase concentrations were significantly increased in both the groups when compared to controls. Erythrocyte glutathione significantly decreased in nephrotic syndrome in remission along with plasma vitamin E concentrations in both the groups. A significant increase in plasma ceruloplasmin was observed in cases in remission. However, no significant change was observed in the concentrations of erythrocyte malondialdehyde. CONCLUSION Thus, antioxidant concentrations change considerably, indicating a compensatory mechanism to cope up with increased pro-oxidant status in such cases.
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Affiliation(s)
- Rajani Kamireddy
- Department of Biochemistry, Kasturba Medical College, Manipal-576 119, Karnataka, India
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55
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Covas MI, Elosua R, Fitó M, Alcántara M, Coca L, Marrugat J. Relationship between physical activity and oxidative stress biomarkers in women. Med Sci Sports Exerc 2002; 34:814-9. [PMID: 11984300 DOI: 10.1097/00005768-200205000-00014] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To examine the relationship between physical activity and levels of plasma lipid peroxides, superoxide dismutase in erythrocytes (SOD), and glutathione peroxidase (GSH-Px) in whole blood activities. METHODS Cross-sectional study in 488 Spanish women. Two categories of leisure time physical activity were defined according to their intensity: low (<or=6 METs) and high (>6 METs). Energy expenditure in household activities was also recorded. Multivariate linear regression analyses were used to adjust for the effect of physical activity on lipid peroxides and SOD and GSH-Px for confounding variables. RESULTS The amount of leisure time physical activity was associated with high activity levels of SOD (P = 0.022) and GSH-Px (P = 0.002). Similar results were obtained when physical activity in household activities was added to total leisure physical activity. Physical activity of low intensity was associated with high SOD activity levels (P = 0.002) and that of high intensity with high GSH-Px activity levels (P = 0.001). CONCLUSION The amount and intensity of leisure physical activity were directly related to both antioxidant enzyme activity levels. The findings of this study suggest a modulatory effect of leisure physical activity intensity on antioxidative balance in the studied female population.
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Affiliation(s)
- Maria-Isabel Covas
- Unitat de Lípids i Epidemiologia Cardiovascular, Institut Municipal de Investigació Mèdica, IMIM, Barcelona, Spain.
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56
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Robbins ME, Zhao W, Davis CS, Toyokuni S, Bonsib SM. Radiation-induced kidney injury: a role for chronic oxidative stress? Micron 2002; 33:133-41. [PMID: 11567882 DOI: 10.1016/s0968-4328(01)00006-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Kidney irradiation clearly leads to a progressive reduction in function associated with concomitant glomerulosclerosis and/or tubulointerstitial fibrosis. However, the particular cell types, mediators and/or mechanisms involved in the development and progression of radiation nephropathy remain ill defined. Angiotensin II (Ang II) plays a major pathogenic role; administration of Ang II blockers markedly abrogates the severity of radiation nephropathy in experimental models. Both ionizing radiation and Ang II signal via generation of reactive oxygen species (ROS). Thus, we hypothesized that localized kidney irradiation might lead to a chronic oxidative stress. In view of the difficulty in measuring ROS in vivo we adopted an indirect immunohistochemical approach in which we used a monoclonal antibody specific for 8-hydroxy-2'-deoxyguanosine (8-OHdG), one of the most commonly used markers of DNA oxidation. The right kidney of 7-8 week-old male Sprague-Dawley rats was removed. Five to 6 weeks later the remaining hypertrophied kidney was irradiated with single doses of 0-20.0 Gy X-rays. Groups of rats, three per dose, were killed at 4, 8, 16 and 24 weeks post-irradiation, their kidneys fixed, and sections stained with the 8-OHdG-specific antibody N45.1. For quantitation of glomerular DNA oxidation with the N45.1 antibody stained sections, 50 glomeruli/animal were counted. The presence of any intensely stained nuclei within the glomerular tuft was scored as positive. Quantitation of tubular DNA oxidation employed a 10 x 10 point ocular grid. Sections were examined at 400 magnification; 250 tubular profiles were counted. All tubules with any nuclear staining were scored as positive.Sham-irradiated kidneys showed little evidence of DNA oxidation over the experimental period. In contrast, localized kidney irradiation led to a marked, dose-independent increase in glomerular and tubular cell nuclear DNA oxidation. This increase was evident at the first time point studied, i.e. 4 weeks after irradiation, and persisted for up to 24 weeks postirradiation. DNA oxidation in the irradiated kidney was only seen in apparently viable glomerular and tubular cells. Thus, while from 16 to 24 weeks post-irradiation structural alterations had progressed to glomerular sclerosis and tubular atrophy, positive staining for 8-OHdG was not observed in severely atrophic tubules. Similarly, fewer positive staining cells were noted in glomeruli undergoing sclerosis, while none were seen in totally sclerotic glomeruli. These data support the hypothesis that renal irradiation is associated with a chronic and persistent oxidative stress.
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Affiliation(s)
- Mike E Robbins
- Free Radical and Radiation Biology Program, Department of Radiology, The University of Iowa, B-180 ML, Iowa City, IA 52242, USA.
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57
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Suwannaroj S, Lagoo A, Keisler D, McMurray RW. Antioxidants suppress mortality in the female NZB x NZW F1 mouse model of systemic lupus erythematosus (SLE). Lupus 2001; 10:258-65. [PMID: 11341102 DOI: 10.1191/096120301680416940] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Inflammation produces reactive oxygen intermediates (ROI) that cause vascular damage and activate T lymphocytes. Conversely, antioxidants not only protect tissue from oxidative damage but also suppress immune reactivity. The objective of this study was to examine immunomodulatory effects of the non-enzymatic antioxidants, N-acetylcysteine (NAC) and cysteamine (CYST), on autoimmune disease, glomerulonephritis, and mortality in the female B/W mouse model of human systemic lupus erythematosus (SLE). The development of murine lupus was assessed during the lifespan of female B/W mice given NAC or CYST. Morbidity and mortality were assessed daily. At 6 week intervals mice were examined for weight change, albuminuria, serum BUN, antibodies to DNA, and IgG immunoglobulin levels. Serum prolactin, estrogen and progesterone were measured at 18 weeks of age. In a parallel study, NAC- and CYST-treated and control B/W mice were examined at 24 weeks of age for interval renal histopathology, lymphocyte adhesion molecule expression, and antibody titers and in vitro cytokine production in response to immunization with DNP-KLH. CYST significantly suppressed development of albuminuria and azotemia at 36 and 42 weeks of age compared to control and NAC-treated mice. NAC significantly suppressed anti-DNA antibody levels at 24 weeks. In contrast CYST significantly increased anti-DNA antibody levels at 18 weeks of age (P < 0.001 CYST vs control and NAC-treated mice). Kidneys of CYST-treated mice also had accelerated inflammatory histologic changes despite their lower incidence of albuminuria and azotemia. Mean (+/- s.e.m.) survival of control mice was 33 +/- 2 weeks compared to 38 +/- 2 weeks in NAC-treated mice (P < 0.05 vs control), and 48 +/- 2 weeks in the CYST-treated group (P < 0.01 vs control mice). The antioxidants, NAC and CYST, significantly improved mortality in the female B/W mouse model of SLE. NAC suppressed autoantibody formation and modestly prolonged survival. CYST, despite its augmentation of anti-DNA levels and renal inflammatory changes, inhibited the development of renal insufficiency and markedly improved survival. These findings suggest that ROIs play a role in the pathogenesis of lupus nephritis and that antioxidants reduce the damage causing renal insufficiency. Antioxidants may be a beneficial adjunctive therapy in the treatment of human SLE.
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Affiliation(s)
- S Suwannaroj
- Division of Rheumatology, Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
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58
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Morcos M, Borcea V, Isermann B, Gehrke S, Ehret T, Henkels M, Schiekofer S, Hofmann M, Amiral J, Tritschler H, Ziegler R, Wahl P, Nawroth PP. Effect of alpha-lipoic acid on the progression of endothelial cell damage and albuminuria in patients with diabetes mellitus: an exploratory study. Diabetes Res Clin Pract 2001; 52:175-83. [PMID: 11323087 DOI: 10.1016/s0168-8227(01)00223-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Oxidative stress plays a central role in the pathogenesis and progression of late microangiopathic complications (diabetic nephropathy) in diabetes mellitus. Previous studies suggested that treatment of diabetic patients with the antioxidant alpha-lipoic acid reduce oxidative stress and urinary albumin excretion. In this prospective, open and non-randomized study, the effect of alpha-lipoic acid on the progression of endothelial cell damage and the course of diabetic nephropathy, as assessed by measurement of plasma thrombomodulin and urinary albumin concentration (UAC), was evaluated in 84 patients with diabetes mellitus over 18 months. Forty-nine patients (34 with Type 1 diabetes, 15 with Type 2 diabetes) had no antioxidant treatment and served as a control group. Thirty-five patients (20 with Type 1 diabetes, 15 with Type 2 diabetes) were treated with 600 mg alpha-lipoic acid per day. Only patients with an urinary albumin concentration <200 mg/l were included into the study. After 18 months of follow up, the plasma thrombomodulin level increased from 35.9+/-9.5 to 39.7+/-9.9 ng/ml (P<0.05) in the control group. In the alpha-lipoic acid treated group the plasma thrombomodulin level decreased from 37.5+/-16.2 to 30.9+/-14.5 ng/ml (P<0.01). The UAC increased in patients without alpha-lipoic acid treatment from 21.2+/-29.5 to 36.9+/-60.6 ng/l (P<0.05), but was unchanged with alpha-lipoic acid. It is postulated that the significant decrease in plasma thrombomodulin and failure of UAC to increase observed in the alpha-lipoic acid treated group is due to antioxidative effects of alpha-lipoic acid, and if so that oxidative stress plays a central role in the pathogenesis of diabetic nephropathy. Furthermore, progression of the disease might be inhibited by antioxidant drugs. A placebo-controlled study is needed.
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Affiliation(s)
- M Morcos
- Department of Internal Medicine I, University of Heidelberg, Bergheimerstr. 58, 69115 Heidelberg, Germany.
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59
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Abstract
Virtually all renal diseases progress to terminal renal failure relatively independently of the initial disease. Arresting the rate of the deterioration of kidney failure has a great impact on reducing the number of patients reaching the stage of expensive renal replacement therapy. Understanding the mechanisms of the progression of kidney disease has greatly been improved during recent years. The nature of the progressive renal damage with various etiologies includes various well-known factors where hemodynamics, renin-angiotensin system (RAS) and progressive proteinuria play the central roles. Proteinuria has to be shown as an independent risk factor for renal disease progression. Also, disturbances in lipid metabolism as well as the later structural lesions contribute to the progression. Various modalities have been used for the prevention of progressive renal disease, e.g. low-protein diet, antihypertensive therapy, antifibrotic therapy. Many recent experimental and clinical studies have shown that besides the systemic blood pressure lowering effect, RAS blocking agents provide renal protective effects via direct, hemodynamic, and indirect, non-hemodynamic, pathways: (1) lowering intraglomerular capillary hydraulic pressure, and increasing the glomerular ultrafiltration coefficient; (2) lowering proteinuria; (3) lowering hyperlipidemia; (4) diminishing kidney growth; (5) diminishing infiltration of macrophages; (6) downregulation of proinflammatory cytokines. Therefore, RAS blocking agents are widely prescribed not only for antihypertensive but also for renoprotective purposes in diabetic and non-diabetic nephropathies.
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Affiliation(s)
- M Ots
- Department of Internal Medicine, University of Tartu, 6 Puusepa Str., 51014, Tartu, Estonia.
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60
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Seo MS, Kim JK, Lim Y, Kang SW, Cho YJ, Lee WK, Kim HJ, Cho KK, Lee KH, Rhee SG. Rapid degradation of PrxI and PrxII induced by silica in Rat2 cells. Biochem Biophys Res Commun 1999; 265:541-4. [PMID: 10558905 DOI: 10.1006/bbrc.1999.1709] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Peroxidases of the peroxiredoxin (Prx) family catalyze the reduction of H(2)O(2) and lipid peroxides. The effects of H(2)O(2), 12-O-tetradecanoylphorbol 13-acetate (TPA), and silica on the abundance of two cytosolic isoforms of Prx (PrxI and PrxII) were examined in Rat2 cells. TPA induces the production of reactive oxygen species (ROS) in various mammalian cell types, and silica induces the production of ROS in Rat2 cells. Whereas H(2)O(2) and TPA did not affect the concentration of PrxI or Prx II, silica triggered a rapid degradation of both Prx enzymes. Silica also induced degradation of the NF-kappaB inhibitor IkappaB-alpha. N-Acetylcysteine and diphenyleneiodonium, both of which inhibit the accumulation of intracellular ROS, each blocked silica-induced degradation of IkappaB-alpha but had no effect on that of the Prx enzymes, suggesting that ROS do not contribute to Prx proteolysis. The silica-induced degradation of Prx enzymes was also insensitive to the proteasome inhibitors MG132 and lactacystin, whereas IkappaB-alpha proteolysis was completely blocked by these inhibitors. Experiments with the Ca(2+) ionophore A23187 indicated that a Ca(2+)-dependent protease such as calpain might contribute substantially to silica-induced degradation of PrxII, but only moderately to that of PrxI. These results indicate that silica increases cellular oxidative stress not only by inducing ROS production, but also by triggering the degradation of Prx enzymes that are responsible for elimination of cellular ROS. Such aggravated oxidative stress might be important in the initial pathogenesis of silica-associated pulmonary diseases.
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Affiliation(s)
- M S Seo
- College of Medicine, The Catholic University of Korea, Seoul, 137-701, Korea
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61
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Andersson A, Lindgren A, Arnadottir M, Prytz H, Hultberg B. Thiols as a Measure of Plasma Redox Status in Healthy Subjects and in Patients with Renal or Liver Failure. Clin Chem 1999. [DOI: 10.1093/clinchem/45.7.1084] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
| | | | | | - Hanne Prytz
- Internal Medicine, University Hospital, S-221 85 Lund, Sweden
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62
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Lipman RD, Bronson RT, Wu D, Smith DE, Prior R, Cao G, Han SN, Martin KR, Meydani SN, Meydani M. Disease incidence and longevity are unaltered by dietary antioxidant supplementation initiated during middle age in C57BL/6 mice. Mech Ageing Dev 1998; 103:269-84. [PMID: 9723903 DOI: 10.1016/s0047-6374(98)00048-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ability of augmented antioxidant consumption to alter disease incidence, lesion burden and/or longevity was studied in adult male C57BL/6 mice. Mice were fed modified AIN76 diet or modified AIN76 supplemented with vitamin E, glutathione (GSH), vitamin E and GSH, melatonin or strawberry extract starting at 18 months of age. All the mice in this study were heavier than reference populations of male C57BL/6 mice fed NIH-07 or NIH-31, which were maintained without a mid-life change in diet. Fatty liver, focal kidney atrophy and proteinacious casts in the renal tubules were observed more frequently in this study population than in the reference populations. Lesion burden and incidence of specific lesions observed amongst the various groups in this study did not differ. There were no differences observed for longevity of any of the study groups. The longevity observed in this study was similar to that previously reported for male C57BL/6 mice. Thus, diet supplementation with antioxidants initiated during middle age did not appear to affect age-associated lesions patterns, lesion burden or longevity for ad libitum fed male C57BL/6 mice.
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Affiliation(s)
- R D Lipman
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
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63
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Abstract
Ferrochelatase catalyzes the chelation of ferrous iron and protoporphyrin to form heme. It is expressed as a housekeeping gene in all cells, but is upregulated during erythropoiesis. Ferrochelatase activity is deficient in the inherited disease protoporphyria as a result of heterogeneous mutations. Although human ferrochelatase is transcribed from a single promoter in both nonerythroid and erythroid cells, previous studies using transient transfection assays failed to demonstrate erythroid-specific increased expression from 4.0 kb of the human ferrochelatase promoter containing the erythroidcis-elements, GATA and NF-E2. The present study analyzes the in vivo regulation of the ferrochelatase gene to provide insights into the mechanism of its erythroid-specific enhancement. Transgenic (TG) mouse lines were generated in which the luciferase reporter gene was driven by either a 150-bp ferrochelatase minimal promoter (−0.15 TG) or by a 4.0 kb extended 5′ upstream region (−4.0 TG). Expression of the −4.0 TG transgene was generally consistent with the endogenous gene during embryonic development and in nonerythroid and erythroid tissues as demonstrated by Northern blotting and mRNA in situ hybridization. The −4.0 TG was expressed at a higher level than the −0.15 TG in nonerythroid and erythroid tissues, including during extramedullary erythropoiesis induced by n-acetylphenylhydrazine injection. The enhanced erythroid expression of the −4.0 TG correlates with the appearance of a DNase I hypersensitive site in the 5′ flanking region of the transgene. Therefore, in the context of chromosomal integration, the 5′ flanking region of the ferrochelatase gene is necessary and sufficient to confer high levels of transgene expression in erythroid tissue.
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64
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Cristol JP, Vela C, Maggi MF, Descomps B, Mourad G. Oxidative stress and lipid abnormalities in renal transplant recipients with or without chronic rejection. Transplantation 1998; 65:1322-8. [PMID: 9625013 DOI: 10.1097/00007890-199805270-00007] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The histological picture of chronic rejection with endothelial lesions and vascular hyperplasia resembles the early arteriosclerotic lesions. As increasing evidence suggests a role for oxidative stress in arteriosclerosis, we examined whether chronic rejection in renal transplant recipients was associated with increased oxidative stress markers. METHODS We investigated lipid metabolism and oxidative stress in 77 renal transplant recipients. Group I patients (n=34; 48+/-2 years old, 12 women, 22 men) had no clinical or histological signs of chronic rejection, whereas group II patients (n=43; 47+/-3 years old, 15 women, 28 men) had histologically proven chronic rejection. All patients were treated with cyclosporine and steroids. Lipid metabolism was evaluated by determining total cholesterol, triglycerides, high-density lipoprotein cholesterol, apolipoproteins AI and B, and lipoprotein (a). Oxidative stress was evaluated by determining: (i) the end product of lipid peroxidation, malonyldialdehyde (MDA), and erythrocyte polyunsaturated fatty acids; (ii) the nonenzymatic antioxidant system: erythrocyte alpha-tocopherol and glutathione; and (iii) the enzymatic antioxidant system: erythrocyte superoxide dismutase and plasma glutathione peroxidase. Results were compared with those of a control group (38 healthy volunteers). RESULTS Compared with controls, renal transplant recipients had significantly increased total cholesterol, triglyceride, and apolipoprotein B levels; they also had, in association with these lipid abnormalities, a significant increase in MDA and a significant decrease in erythrocyte polyunsaturated fatty acids, as well as a significant decrease in enzymatic and nonenzymatic antioxidant defense mechanisms. In contrast to lipid disturbances, where no difference was observed between groups I and II, markers of oxidative stress were significantly higher in group II compared with group I (MDA: 1.87+/-0.43 and 1.62+/-0.31 nmol/ml, respectively, P<0.05). The red blood cell antioxidative defense mechanisms were significantly decreased in group II compared with controls (erythrocyte alpha-tocopherol: 0.61+/-0.38 and 1.08+/-0.31 mg/L, respectively, P<0.01; superoxide dismutase: 1.08+/-0.2 and 1.32+/-0.31 U/mg Hb, respectively, P<0.01). CONCLUSION Our data show that oxidative stress with a decrease in antioxidant defenses is associated with kidney transplantation. In addition, oxidative stress markers are particularly increased in transplant recipients with chronic rejection, which suggests that oxidative stress may participate in the development and/or progression of vascular lesions observed in these patients.
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Affiliation(s)
- J P Cristol
- Biochemistry Department, University Hospital Lapeyronie, Montpellier, France
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