Context: Elevated oxidative stress plays a key role in diabetes-associated vascular disease. Excessive production of reactive oxygen species via advanced glycation end products (AGEs) activates peroxisome proliferator-activated receptor gamma (PPAR gamma) and the transcription factor nuclear factor-kB (NF-kappa B) in aortic vascular smooth muscle cells (VSMCs). Apocynin, a drug with an antioxidant effect, has also been proposed as a therapeutic agent for atherosclerotic disease.Objectives: This work investigates the effects of apocynin on the PPAR gamma and NF-kappa B protein expression evoked by AGEs in cultured VSMCs from Goto-Kakisaki (GK) rats, a non-obese insulin model of both insulin resistance and type 2 diabetes.Materials and methods: VSMCs, isolated from aortas of GK and non-diabetic rats, were cultured. The expression of proteins was evaluated by Western blot. The blood glucose concentration was measured with a blood glucose test meter. The diabetes of GK rats was controlled by blood glucose and insulin determinations (non-fasting values). The serum insulin concentration was determined by radioimmunoassay.Results: In VSMCs from non-diabetic and GK rats, apocynin (1 and 10 mu m) abolished the protein overexpression of NF-kappa B induced by glycated bovine serum albumin (AGEs-BSA) incubation. However, apocynin (1 and 10 mu M) enhanced the expression of PPAR gamma protein in the presence of AGEs-BSA (100 mu g/mL) in VSMCs from non-diabetic, but not from GK rats.Conclusion: These findings suggest that apocynin decreases the incidence of alterations in VSMCs induced by AGEs through the reduction of NF-kappa B and may represent an attractive therapeutic approach to treat diabetes mellitus.

The present study was designed to examine the effects of EFA deficiency (EFAD) on biochemical, functional, and structural aspects of the kidney in growing and adult rats fed a normal or EFAD diet for 9 wk after weaning. Food and fluid intake (FI), urine volume, and Na+ and K+ excretions were measured weekly from weeks 4 to 8 by placing the rats in individual metabolic cages for 24 h. At week 9, Li+ and a 5% water load, respectively, were administered at 14 and 1.5 h prior to glomerular and proximal tubular function studies, as assessed by 3-h creatinine (CCr) and Li+ (CLi+) clearances. Hematocrit and urine volume; serum and urine [Cr], [Li+], [Na+], and [K+]; and renal FA distribution were also measured. Data [corrected to 100 g/body weight (bw) and presented as means ±SEM] were significant, at P<-0.05. Despite a similar ingestion of solids from weeks 4 to 7 (weeks 7 to 10 of life), the rats on the EFAD diet showed a decreased body weight from week 5. From weeks 4 to 8, Fl and urine volume were similar for both groups, but the Fl increased at week 6 in the EFAD group; 24-h Na+ and K+ excretions were similar at all weeks, except for an increase in the EFAD group for both ions at week 7. In the EFAD group, CCr and CLi+ decreased by 27 and 56.3%, respectively (385.7±33.4 vs. 280±21.1, and 21.0±2.1 vs. 9.2±1.1 μL/min/100 g; n=9 vs. 10), the latter result suggesting increased proximal reabsorption. The 3-h Na+ and K+ excretions were similar, but the Li+ decreased (0.78±0.06×10−2 vs. 0.32±0.03×10−2 μeq/min/100 g) in the EFAD group, giving additional support to the suggestion. Renal structure was normal and similar for both groups, but the EFAD group showed a more prominent proximal tubule brush border, together with heavier periodic acid-Schiff staining in all specimens from weeks 5 to 9. In the EFAD group, FA of the n−9 and n−7 series were higher, but most of the n−6 series were lower as a percentage of total lipids in the medulla and cortex. Medullary levels of 20∶4n−6 were maintained, 22∶4n−6 declined twice, arachidonic acid was maintained, and 20∶5n−3 was lower. The EFAD diet affected glomerular function, proximal tubular structure and function, and FA distribution in the rat kidney.

Purpose: To determine the association of potential risk factors, including antioxidant enzymes, with the incidence of cataract.Design: Cohort study.Participants: At baseline, the Age-Related Eye Diseases (Pathologies Oculaires Liees a l'Age, POLA) Study included 2584 residents of Sete (southern France) aged 60 years or older. From September 1998 to May 2000, a 3-year follow-up examination was performed on 1947 of the 2436 surviving participants (79.9%).Methods: Cataract classification was based on a standardized lens examination at the slit lamp, according to Lens Opacities Classification System III. Biologic measurements were performed at baseline from fasting blood samples.Main Outcome Measures: At baseline and follow-up, the presence of cataract was defined as: NC or nuclear opalescence (NO) greater than or equal to 4 for nuclear cataract, Cgreater than or equal to4 for cortical cataract, and Pgreater than or equal to2 for posterior cataract (PSC) opacities, using opacity grades corrected for interobserver variability. Incidence rates were assessed separately for right and left eyes and for each type of cataract.Results: In the multivariate model, the incidence of cortical cataract was increased in subjects with high red blood cell superoxide dismutase activity (odds ratio [OR] 4.2 [1.5-12.1], P = 0.007). The incidence of PSC cataract was increased in subjects with a high level of plasma glutathione peroxidase (OR 1.8 [1.0-3.3], P = 0.05). In addition to age, gender, and opacities at baseline, significant risk factors for incident cataract were: long-duration diabetes (OR 5.8, P = 0.001 for cortical cataract) and lifetime heavy smoking (OR 2.9, P = 0.006 for PSC cataract).Conclusions: Consistent with the baseline analysis, the results of this prospective study suggest that antioxidant enzymes might be implicated in the etiology of cataract. (C) 2003 by the American Academy of Ophthalmology.

Using an approach in line with that of a previous report, we assessed the antioxidant activity of several natural, polyphenol- or tocotrienol-rich mixtures: extracts from Elaesis Guineensis oil (A) and Vitis vinifera (B), a Coffea robusta powder (C), and extracts from Olea europea mill wastewaters (D), Solanum melongena (E), and Lycopersicon esculentum (F). The copper- and 2-2'-azobis(2-amidinopropane) hydrochloride (AAPH)-oxidation systems were used in the presence of low-density lipoprotein. For comparison, antioxidant activities of chlorogenic acid and catechin, as archetypes of molecules highly efficient with the copper- and the AAPH-oxidation system, respectively, were assessed. The aim was to establish the occurrence of synergistic antioxidant actions among some of these natural mixtures. On a molar basis, the highest specific antioxidant activities (SAA) were found for B, chlorogenic acid, and C in the copper system, and for A, catechin, and B in the AAPH system. On a mass basis, the highest SAA were found, respectively, for chlorogenic acid, B, and catechin, and for catechin, chlorogenic acid, and B. These results show that large discrepancies take place in the evaluations between the two systems. B and C exhibited a synergistic antioxidant efficiency, in the presence or absence of A, but only with the copper system. This was also true for the two types of A+B+C mixture that were tested. It is thought that this association might provide an ideal combination, incorporating both the radical scavenger and the transition-metal ion chelation properties of B and C.

Malnutrition of children during the first two years of life constitutes a public health concern in Brazil, particularly in the Northeast. Most of the nutrition data are concerned with protein-energy malnutrition and hypovitaminosis A. The purpose of this cross-sectional study was to assess the essential fatty acid (EFA) status, which is crucial in physical and mental development, and that of vitamin E which prevents against the oxidative loss of EFA physiological properties, in 81 full-term newborns. Blood samples were obtained from the residual blood of the umbilical cord (UC) at delivery. Fatty acid composition of UC plasma did not show any sign of EFA deficiency. The levels of docosahexanoic (DHA) and arachidonic acid (AA) appeared to be quite similar to those obtained in European populations. UC plasma vitamin E content was 6.31 +/- 1.99 mumol/L whereas the lipid-normalized vitamin E was 2.36 mumol/mmol of lipids. An interesting point was that newborns with vitamin E inferior to the median value (5.80 mumol/L) revealed significantly lower contents of linoleic acid and DHA in UC than newborns superior to the median value. Together with the absolute or normalized plasma level of vitamin E, this supports the observation that one quarter of the community's newborns is deficient in vitamin E.

We estimated the frequencies of phenotype (isoelectric focusing; IEF) vs. genotype (PCR/Hhal) discordance in a sample of an aged population (> 65 years). Both phenotype and genotype techniques have been used in the study of apolipoprotein E (apoE) polymorphism in 125 elderly subjects. The discordance between phenotype and genotype was unresolved in 11 (8.8%) of the 125 unrelated subjects studied. We observed a significant association between the presence of the E4 allele and both Alzheimer's disease (chi2 = 13, p < 0.001) and increased cholesterol concentration (Mann Whitney, p < 0.03). These relationships were not affected by the techniques used. Our results indicate that transcriptional modulation and post-transductional modifications in normal ageing and in aged-related diseases may explain in part discrepancies between gene analysis and protein characterisation.

The effect of N-ethyl-maleimide (NEM) on Δ5-and Δ6-desaturase activities and the incorporation of substrates and products into different microsomal lipid classes and phospholipid (PL) subclasses were studied in human fetal liver microsomes, obtained after legally approved therapeutic abortion. Desaturase activities were measured by a radiochemical method using reversed-phase high-performance liquid chromatography (HPLC). After nonphospholipid (NPL) and PL separation on silica cartridges, the radioactivity in different lipids of the NPL group was assessed by two-dimensional thin-layer chromatography, and their fatty acid (FA) composition by gas-liquid chromatography. The PL subclasses were separated, and the distribution of radioactivity between products and substrates was determined in PL subclasses. NEM inhibited the Δ5- and Δ6-desaturase activities in the n−6 series of FA but not the Δ6-desaturase activity in the n−3 series, which suggests the existence of two distinct Δ6-desaturases, one for the n−6 series and another for the n−3 series. Whether NEM was present or absent, most of the radioactivity was recovered in the free FA form (about 80%). The desaturation products, obtained in the presence or absence of NEM, were preferentially incorporated into PL, suggesting a channeling of the newly synthesized FA toward microsomal PL. The comparison of the distribution of substrates and products incorporated into the different PL classes showed that most of the labeled FA were incorporated into phosphatidylcholine and to a lesser degree into phosphatidylethanolamine.

LipidsVolume 34, Issue S1Part3 p. S293-S293 Lipid Peroxidation Vitamin E inhibition of O2·− production in the promonocyte cell line THP-1 is essentially due toRRR-δ-tocopherol Laurence Brillant, Laurence Brillant Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this authorClaude Louis Léger, Claude Louis Léger Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this authorBernard Descomps, Bernard Descomps Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this author Laurence Brillant, Laurence Brillant Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this authorClaude Louis Léger, Claude Louis Léger Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this authorBernard Descomps, Bernard Descomps Laboratoire de Biologie et Biochimie des Lipides, UPRES-EA 2033 Institut de Biologie, Université Montpellier I, Montpellier, 34060 FranceSearch for more papers by this author First published: 01 January 1999 https://doi.org/10.1007/BF02562322Citations: 4 To whom correspondence should be addressed. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume34, IssueS1Part3January 1999Pages S293-S293 RelatedInformation

Objective: To evaluate the polyunsaturated fatty acid (PUFA) status in non-institutionalised elderly women and to detect a possible essential fatty acid bioconversion defect. Design and subjects: The fatty acid composition of total plasma lipids, plasma triglycerides (TG), cholesterol esters (CE), phospholipids (PL), and erythrocytes was determined by capillary column gas-liquid chromatography in a sample of 200 non-institutionalised healthy elderly women over 75 years of age. The data were compared with those of a control group of 50 young female volunteers aged 20–48 y. Results: In elderly women, the n-6 series precursor, linoleic acid (18:2 n-6), was lower in TG and CE (P=0.029 and 0.014, respectively). In CE, this fatty acid was highly correlated with vegetable and vegetal fat intakes (P<0.0001), suggesting a lower dietary supply than in controls. Higher percentages of 16:1 n-7 were found in all the plasma lipid fractions in elderly women, especially in CE (P<0.0001). The ratios 20:4 n-6/20:3 n-6 and 22:6 n-3/20:5 n-3 were significantly lower in PL from elderly women (P<0.005 and P<0.002, respectively), raising the question of the efficiency of the terminal steps of 20:4 n-6 and 22:6 n-3 biosynthesis. Dietary investigations in elderly women indicated that a high dietary protein intake via meat probably contributed to the supply of 20:4 n-6 and thus maintained the status of this fatty acid, despite the suspected altered biosynthesis. Conclusion: The PUFA status in the elderly women group could be more fragile and dependent on exogenous supply of long-chain PUFAs than previously suspected.

Vitamin E (α-tocopherol), one of the most important natural antioxidants, is assumed to be beneficial in the prevention of cardiovascular diseases. α-Tocopherol exhibits acyl-peroxyl-radical scavenger properties and exerts cell-mediated actions in the hemovascular compartment, such as inhibition of superoxide anion (O⨪2) production by leukocytes. The aim of this study was to examine the mechanism underlying the inhibitory effect of α-tocopherol on O⨪2 production by human monocytes. In activated monocytes O⨪2 is produced by the NADPH-oxidase enzyme complex. The oxidase activation elicited by phorbol myristate acetate (PMA) requires membrane translocation of several cytosolic factors. We found that in human PMA-stimulated adherent monocytes, α-tocopherol (but not β-tocopherol) inhibited O⨪2production in intact cells but had no effect on a membrane preparation containing activated NADPH-oxidase, suggesting that α-tocopherol impairs the assembly process of the enzyme complex. We showed that translocation and phosphorylation of the cytosolic factor p47 phox were reduced in monocytes preincubated with α-tocopherol. We verified that the tryptic phosphopeptide map of monocyte p47 phox was similar to that of neutrophil p47 phox , indicating that several serine residues were phosphorylated. Peptides whose phosphorylation is dependent on protein kinase C (PKC) were phosphorylated to a lesser degree when p47 phox was immunoprecipitated from α-tocopherol-treated monocytes. In vitro, the activity of PKC from monocytes was inhibited by α-tocopherol in a specific manner compared with that of β-tocopherol or Trolox®. Membrane translocation of PKC was not affected. These results show that α-tocopherol inhibits O⨪2production by human adherent monocytes by impairing the assembly of the NADPH-oxidase and suggest that the inhibition of phosphorylation and translocation of the cytosolic factor p47 phox results from a decrease in PKC activity.

It is commonly accepted that oxidized low-density lipoprotein (ox-LDL) plays an important role in coronary heart disease (CHD) and etiologically related atherogenesis. Consumption of wine may contribute to the low risk of CHD in the Mediterranean population. These findings raise the question of the in vivo antioxidant role of wine phenolic compounds after a prolonged supplementation period in healthy human volunteers. We found that subjects, receiving 2 g/d of an alcohol-free red wine-extracted phenolic compound (RWPC) mixture for 14 d (which was equivalent to about 1 L/d of the red wine), exhibited an increase in the plasma antioxidative capacity and in LDL vitamin E by blood sampling under fasting conditions. The fact that the LDL Cu2+-oxidizability was not decreased can be explained by both the lack of phenolic compound affinity for the lipoprotein particle, highlighted by LDL dialysis, and the insufficient increase in LDL vitamin E, as shown by the relationship between vitamin E content and oxidation resistance of LDL evidenced by literature data. These results support that RWPC could play a coantioxidant role, similar to that of vitamin C, possibly accounting for their LDL vitamin E sparing effect and their beneficial role in lowering CHD risks.

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.

Vitamin E (α-tocopherol) is a potent peroxyl radical scavenger. According to the oxidative theory of atherosclerosis, it prevents oxidation of low-density lipoprotein (LDL) and thereby lowers the risk of cardiovascular disease. It also mediates cell actions, and specifically decreases monocyte superoxide anion-production (O2--production), which is involved in LDL oxidation. We investigated whether α-tocopherol-containing LDL decreases this production in a manner dependent on the LDL α-tocopherol content (the α-tocopherol/apoB molar ratio) in human, phorbol ester-stimulated, adherent monocytes. We found that O2--production was inhibited by native LDL (n-LDL) in a manner highly sensitive to the increasing α-tocopherol content (range 4.5–8). In addition: (1) inhibition was greater when α-tocopherol was associated to acetylated LDL (ac-LDL), the maximal percentage of inhibition being 80% as opposed to 35% for n-LDL; (2) the α-tocopherol overloading of either form of LDL did not produce further inhibition; (3) the free form of α-tocopherol produced lower inhibition compared with the lipoprotein-associated forms; (4) inhibition was not related to the cell content of α-tocopherol. We propose that the cell targeting of α-tocopherol is crucial to the inhibition of monocyte O2−-production, and thus that the role of normal LDL-α-tocopherol contents (range 6–8) in the prevention of atherogenic processes needs to be reexamined.