Effects of vitamin E supplementation on blood antioxidants levels in patients with Behçet's disease

A systematic review and meta-analysis of neopterin in rheumatic diseases

Introduction

Novel biomarkers of inflammation and oxidative stress might enhance the early recognition, management, and clinical outcomes of patients with rheumatic diseases (RDs). We assessed the available evidence regarding the pathophysiological role of neopterin, the oxidation product of 7,8-dihydroneopterin, a pteridine generated in macrophages activated by interferon-γ, by conducting a systematic review and meta-analysis of studies reporting its concentrations in biological fluids in RD patients and healthy controls.

Methods

We searched electronic databases for relevant articles published between inception and 31 August 2023. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and the Grades of Recommendation, Assessment, Development and Evaluation Working Group system, respectively.

Results

In 37 studies, when compared to healthy controls, RD patients had significantly higher concentrations of neopterin both in plasma or serum (standard mean difference, SMD=1.31, 95% CI 1.01 to 1.61; p<0.001; moderate certainty of evidence) and in the urine (SMD=1.65, 95% CI 0.86 to 2.43, p<0.001; I2 = 94.2%, p<0.001; low certainty of evidence). The results were stable in sensitivity analysis. There were non-significant associations in meta-regression and subgroup analysis between the effect size and age, male to female ratio, year of publication, sample size, RD duration, C-reactive protein, erythrocyte sedimentation rate, specific type of RD, presence of connective tissue disease, analytical method used, or biological matrix investigated (plasma vs. serum). By contrast, the effect size was significantly associated with the geographical area in studies assessing serum or plasma and with the type of RD in studies assessing urine.

Discussion

Pending additional studies that also focus on early forms of disease, our systematic review and meta-analysis supports the proposition that neopterin, a biomarker of inflammation and oxidative stress, can be useful for the identification of RDs. (PROSPERO registration number: CRD42023450209).

Systematic review registration

PROSPERO, identifier CRD42023450209.

Influence of Titanium Alloy Scaffolds on Enzymatic Defense against Oxidative Stress and Bone Marrow Cell Differentiation

Studies have been directed towards the production of new titanium alloys, aiming for the replacement of Ti-6 Aluminium-4 Vanadium (TiAlV) alloy in the future. Many mechanisms related to biocompatibility and chemical characteristics have been studied in the field of implantology, but enzymatic defenses against oxidative stress remain underexplored. Bone marrow stromal cells have been explored as source of cells, which have the potential to differentiate into osteoblasts and therefore could be used as cells-based therapy. The objective of this study was to evaluate the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in porous scaffolds of Ti-6 Aluminium-4 Vanadium (TiAlV), Ti-35 Niobium (TiNb), and Ti-35 Niobium-7 Zirconium-5 Tantalum (TiNbZrTa) on mouse bone marrow stromal cells. Porous titanium alloy scaffolds were prepared by powder metallurgy. After 24 hours, cells plated on the scaffolds were analyzed by scanning electron microscopy (SEM). The antioxidant enzyme activity was measured 72 hours after cell plating. Quantitative real time PCR (qRT-PCR) was performed after 3, 7, and 14 days, and Runx2 (Runt-related transcription factor2) expression was evaluated. The SEM images showed the presence of interconnected pores and growth, adhesion, and cell spreading in the 3 scaffolds. Although differences were noted for SOD and CAT activity for all scaffolds analyzed, no statistical differences were observed (p > 0.05). The osteogenic gene Runx2 presented high expression levels for TiNbZrTa at day 7, compared to the control group (TiAlV day 3). At day 14, all scaffolds had more than 2-fold induction for Runx2 mRNA levels, with statistically significant differences compared to the control group. Even though we were not able to confirm statistically significant differences to justify the replacement of TiAlV regarding antioxidant enzymes, TiNbZrTa was able to induce faster bone formation at early time points, making it a good choice for biomedical and tissue bioengineering applications.

Thiol/disulfide homeostasis in patients with ocular-active and ocular-inactive Behçet disease

PURPOSE

To evaluate thiol/disulfide homeostasis in ocular-active (OA) and ocular-inactive (OI) Behçet disease (BD) patients and compare the data with healthy subjects.

METHODS

Twenty OABD patients, 20 OIBD patients and 20 healthy control subjects were included into the study. The BD ocular attack score 24 (BOS24) scoring system was used to assess the activity of disease in ocular BD patients. Systemic activity was also evaluated using BD current activity form (BDCAF). The native thiol (NT), total thiol (TT) and disulfide levels and NT/TT, disulfide/NT and disulfide/TT ratios were measured via using an innovative and automated method.

RESULTS

BOS24 and BDCAF scores were 13.25 ± 2.32 and 4.18 ± 2.06 in OABD patients and 0.31 ± 0.47 and 2.14 ± 1.98 in OIBD patients, respectively. The NT, TT levels and NT/TT ratio were significantly reduced; in contrast, the disulfide levels, disulfide/NT and disulfide/TT ratios were significantly increased in OABD and OIBD patients compared to the healthy control subjects (p < 0.05). Moreover, while the levels of NT and TT were significantly reduced, the disulfide levels as well as disulfide/NT and disulfide/TT ratios were significantly elevated between OABD and OIBD patients (p < 0.05). However, the ratio of NT/TT did not significantly differ between OABD and OIBD patients (p = 0.449). The multiple regression model including BOS24 and BDCAF score statistically significantly predicted NT level, TT level and disulfide level (p < 0.001 for all).

CONCLUSION

Thiol oxidation in BD patients resulted in a change of the thiol/disulfide balance. Therefore, thiol/disulfide homeostasis in BD patients can be used an innovative oxidative stress marker.

Investigation of pregnancy associated plasma protein-A and neopterin levels in Behçet's patients

Behçet's disease (BD) is an autoimmune disease that affects many organs. We aimed to investigate the relationship between BD and these pregnancy-associated plasma protein A (PAPP-A), neopterin, and high sensitive C-reactive protein (hsCRP) parameters. The study included 57 BD patients and 54 healthy controls. After evaluating the active and inactive disease status of the patients, analyzes were performed. When comparing the patient and control groups, neopterin (111.27 ± 37.49; 76.77 ± 38.27 [nmol/L]; P < .001) and hsCRP (11.81 ± 16.8; 3.62 ± 5.06 [mg/L]; P = .001) parameters were significantly higher in patients. Neopterin (117.68 ± 41.67; 94.85 ± 14.75 [nmol/L]; P = .038) and hsCRP (14.68 ± 18.7; 4.47 ± 7.27 [mg/L]; P = .002) found different in active and inactive patients. The sensitivities of neopterin and hsCRP were also found to be high in BD (respectively 93%, 67%). PAPP-A was especially elevated in skin pathologies (P = .02) and neopterin in joint involvement (P = .03). We think that the use of neopterin and hsCRP can help in diagnosis and follow-up of BD.

The Effect of Dietary Supplementation of Vitamin E, Selenium, Zinc, Folic Acid, and N-3 Polyunsaturated Fatty Acids on Sperm Motility and Membrane Properties in Dogs

Simple Summary

Practitioners look for specific treatments to solve sub-fertility, which nowadays represents a common challenge in canine reproduction. In human, as well as in veterinary medicine, several dietary protocols have been developed to relieve poor sperm concentration and function. They both are constraining factors of breeding programs. Particularly, food supplementation should include micronutrients and anti-oxidants in balanced amounts, exploiting their synergistic actions. Thus, the cumulative effect of vitamin E, selenium, zinc, folic acid, and n-3 polyunsaturated fatty acids (PUFA) on sperm motility and membrane properties was investigated in healthy normospermic dogs. Results of a 90-day-long supplementation period were compared to a control group, not receiving any dietary integration. The positive results obtained in healthy subjects on sperm motility and membrane properties lead us to consider the opportunity to further use the dietary strategy to improve seminal parameters in sub-fertile dogs, too, as reported for other species. Food supplementation and a balanced diet can be pointed out as cheap and safe alternatives within an innovative multimodal approach to improve reproductive performances in healthy dogs.

Abstract

Sub-fertility represents a common challenge in canine reproduction. Different protocols, supplementing daily given quantities of micronutrients, were investigated to improve poor sperm concentration and/or function, which represent breeding major constraining factors in the canine species. Little information is available for dogs concerning the effect of a daily supplementation with a complex of vitamin E, zinc, selenium, folic acid, and n-3 polyunsaturated fatty acids (PUFA) on semen quality. Thus, the present study investigated this effect on semen motility and sperm membrane properties. Serial semen analyses from fourteen healthy normospermic dogs, fed with the same commercial diet, were performed on Days 0 (T0), 30 (T30), 60 (T60), and 90 (T90). Seven dogs were randomly included in the treatment (T) group, receiving a supplementation of vitamin E, zinc, selenium, folic acid, n-3 PUFA; and seven other subjects composed the control (C) group. Total Sperm Count (TSC), Computer-Assisted Sperm Analysis (CASA) indexes, mortality, and functional membrane integrity were assessed. The ANOVA compared results between groups and sampling times (p < 0.05). From T60, the supplementation significantly improved TSC, progressive motility, functional membrane integrity, and decreased mortality. Present results lead us to consider ameliorative effects of a two-month healthy diet supplementation on canine spermatozoa. The positive effects of the described balanced integration of micronutrients on sperm motility and prevention of oxidative stress should be considered, especially when decreased seminal parameters may result from inadequate intake, reduced absorption, increased losses or demand, or to attenuate the impact of age.

Paraoxonase and Arylesterase Levels in Behcet's Disease and Their Relations with the Disease Activity

The aim of this study was to determine the paraoxonase (PON) and arylesterase (ARE) enzyme activity levels in Behcet's disease (BD) and to investigate whether they are associated with the disease activity. Twenty-six patients (study group) with active BD and 28 healthy controls (control group) were included in this study. While the patients who had at least one of the symptoms related to genital ulcer, skin lesions, active uveitis, arthritis, thrombophlebitis, or central nervous system involvement in addition to oral ulcers were considered as the active group, the patients who did not show clinical symptoms in the last one month due to the medical treatment were considered as the inactive group in the clinical evaluation of patients with BD. The PON and ARE levels were found to be significantly lower in the study group than the control group (p < 0.05). The PON levels of the active and inactive groups were 96.23 ± 57.84 and 112.2 ± 65.14, respectively. The ARE levels of the active and inactive groups were 30.49 ± 5.81 and 30.85 ± 6.40, respectively. No significant correlations were found between clinical findings and the activity levels of PON and ARE in the active patient group (p > 0.05). The activities of the antioxidant PON and ARE enzymes are reduced in BD. Therefore, it may be useful to add antioxidant therapy to the conventional treatment of the disease.

Is 4-Hydroxynonenal a Predictive Parameter for the Development of Joint Erosion in Patients With Rheumatoid Arthritis?

Objectives

This study aims to evaluate serum 4-hydroxynonenal (4-HNE) levels and its clinical and radiological significance in patients with rheumatoid arthritis (RA).

Patients and methods

The study included 40 patients (8 males, 32 females; mean age 51.4±11.2 years; range 24 to 72 years) with RA and 30 healthy controls (8 males, 32 females; mean age 53.0±11.7 years; range 24 to 72 years. Serum 4-HNE levels were measured using sandwich enzyme-linked immunosorbent assay method. Patients with disease activity score 28 ≤3.2 and >3.2 were allocated into low and high/moderate disease activity groups, respectively. Additionally, patients were divided into two groups as early RA (disease duration ≤2 years) and established RA (disease duration ≥2 years). Functional disability was evaluated using health assessment questionnaire. Radiographs were scored using the modified Larsen scoring.

Results

Serum 4-HNE levels in patients with RA were significantly higher than controls (p=0.001). Serum 4-HNE levels did not correlate with laboratory or clinical parameters of disease activity including erythrocyte sedimentation rate, C-reactive protein, disease activity score 28, and health assessment questionnaire. Serum 4-HNE levels were higher in patients with established RA than patients with early RA (r=0.487, p=0.001). Besides, modified Larsen score which indicates structural damage correlated significantly with serum 4-HNE levels (p=0.001).

Conclusion

These results indicate that serum 4-HNE levels may be used as an indicator for structural damage such as erosions in the early stage of RA; however, they are not efficient to monitor disease activity.

Therapeutic effects of vitamin E supplementation in 4 dogs with poor semen quality and low superoxide dismutase activity in seminal plasma

Four dogs with poor semen quality, low seminal plasma superoxide dismutase (SOD) activity and low blood plasma testosterone (T) levels were orally administered one vitamin E tablet containing 50 mg α-tocopheryl acetate per dog daily for 4 weeks. The mean values of semen quality were temporarily improved after the start of vitamin E treatment and the values of 4, and 5 weeks after that were significantly different from those before the treatment (P<0.05-0.001). The mean blood plasma T and seminal plasma SOD activity values slightly increased in the 4 dogs after the treatment. The results of the present study indicate that poor semen quality in dogs with low seminal plasma SOD can be improved by vitamin E treatment.

Antistreptolysin O Levels in Patients with Behcet's Disease

OBJECTIVE

Behcet's disease is a multisystem inflammatory disorder, and its etiology has not been defined clearly yet. In this study, we aimed to investigate the antistreptolysin O (ASO) levels of patients with Behcet's disease.

MATERIALS AND METHODS

Thirty patients with Behcet's disease and 30 healthy controls were enrolled in this study. We measured erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and ASO levels in both groups.

RESULTS

There was no statistically significant difference between the two groups with respect to demographic data (p>0.05). The ASO levels of the patients and the controls were 288.4±145.7 and 170.6±142.4 ng/ml, respectively. In the patients with Behcet's disease, ASO (p<0.01) and ESR (p<0.05) values were significantly higher than in the healthy controls. There was no other significant difference in serum CRP levels between the patients and the controls. We could not find any correlation among ASO, CRP, and ESR values.

CONCLUSION

Our results suggest that serum ASO levels may increase in patients with Behcet's disease. Further studies are needed in order to define the relationship between ASO levels and inflammation status in Behcet's disease.

Selenium reduces oxidative stress and calcium entry through TRPV1 channels in the neutrophils of patients with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common inflammatory disease with an uncertain pathogenesis, although one consistent finding is increased neutrophil activity. It has been recently reported that the essential antioxidant element selenium has protective effects on oxidative stress and cytosolic Ca(2+) concentrations in human neutrophil. We aimed to investigate the effects of selenium on oxidative stress and Ca(2+) levels through TRPV1 channels in neutrophils from patients with PCOS. Blood samples were obtained for neutrophil isolation from ten female patients with PCOS and ten healthy female subjects. Neutrophils isolated from PCOS group were investigated in four settings: (1) PCOS, (2) after incubation with TRPV1 channel blocker capsazepine (CPZ), (3) after incubation with selenium (sodium selenite), and (4) with combination (CPZ + selenium) exposure. Intracellular free Ca(2+) concentrations were higher in the patients than those in the controls, although their levels were reduced after CPZ and selenium incubations. The cytosolic Ca(2+) concentrations in neutrophils obtained from PCOS group were further decreased after incubation with CPZ + selenium, as compared with those exposed to neither agent. Lipid peroxidation levels were higher in the PCOS group than those in the control although neutrophil glutathione peroxidase (GSH-Px) and reduced glutathione (GSH) values were decreased. The lipid peroxidation level was lower in the CPZ and selenium groups than that in the PCOS group although GSH and GSH-Px values were higher in the treatment with selenium and CPZ. In conclusion, we observed the importance of Ca(2+) influx into the neutrophils through TRPV1 channels in the pathogenesis of the patients with PCOS. The selenium appeared to provide a protective effect against oxidative stress and Ca(2+) entry through modulation of neutrophil TRPV1 calcium channels.

Hypericum perforatum modulates apoptosis and calcium mobilization through voltage-gated and TRPM2 calcium channels in neutrophil of patients with Behcet's disease

Behcet's disease (BD) is a chronic, inflammatory, and multisystemic condition although its pathogenesis is uncertain. Main component of St. John's wort (Hypericum perforatum, HP) is hyperforin and induces antiinflammatory and antioxidant properties. We aimed to investigate effects of HP on oxidative stress, apoptosis, and cytosolic-free Ca²⁺ [Ca²⁺](i) concentration in neutrophil of BD patients. Nine new-diagnosed active patients with BD and nine control subjects were included in the study. Disease activity was considered by clinical findings. Neutrophil samples were obtained from the patients and controls. The neutrophils from patients were divided into three subgroups and were incubated with HP, voltage-gated calcium channel (VGCC) blockers, (verapamil+dilitiazem) and non-specific TRPM2 channel blocker (2-aminoethyl diphenylborinate, 2-APB), respectively. The neutrophils were stimulated by fMLP as a Ca²⁺-concentration agonist and oxidative stress former. Caspase-3, caspase-9, apoptosis, lipid peroxidation, and [Ca²⁺](i) values were high in the patient groups, although cell viability, glutathione (GSH), and glutathione peroxidase (GSH-Px) values were low in patient group. However, the [Ca²⁺](i), caspase-3, and caspase-9 values decreased markedly in patient+HP group although GSH and GSH-Px values increased in the group. The [Ca²⁺](i) concentration was also decreased in the patient group by V+D, 2-APB, and HP incubations. In conclusion, we observed the importance of neutrophil Ca²⁺ entry, apoptosis, and oxidative stress through gating VGCC and TRPM2 channels in the neutrophils in the pathogenesis and activation of the patients with BD. HP induced protective effects on oxidative stress by modulating Ca²⁺ influx in BD patients.

Serum prolidase enzyme activity and oxidative status in patients with Behçet's disease

OBJECTIVES

To assess serum prolidase enzyme activity and oxidative stress in patients with Behçet's disease (BD).

METHODS

The study population consisted of BD patients (n = 42) and healthy participants (n = 29). BD patients were classified as active (n = 18) or inactive (n = 24) according to disease activity. Serum prolidase enzyme activity, total antioxidant status (TAS), total oxidative status (TOS), oxidative stress index (OSI), and malondialdehyde (MDA) levels were measured.

RESULTS

In BD patients with active disease, serum prolidase activity was significantly higher compared with the inactive and control participants. Serum prolidase activity was also significantly higher in all BD patients in comparison with controls. Serum prolidase activity was also positively correlated with OSI, C-reactive protein, and active BD. MDA, TOS, and OSI levels were all significantly higher in the BD group when compared with the healthy control participants. Serum TAS levels were significantly lower in BD patients in comparison with healthy controls.

CONCLUSION

High prolidase activity may indicate critical biological activities relevant to pathological events in BD, and this activity may be a biological indicator of disease. Further studies are needed to verify these findings.

Catalase and lipid peroxidation values in serum of Tunisian patients with pemphigus vulgaris and foliaceus

Pemphigus is an autoimmune disorder resulting from the interaction between autoantibodies and desmoglein. Oxidative stress seems to be responsible for the onset/aggravation of many human diseases. Actually, it is considered as one of the several factors for the etiopathogenesis of pemphigus. The present study aims to evaluate the oxidative state in the sera of pemphigus vulgaris and pemphigus foliaceus patients by assessing lipid peroxidation, proteins oxidation, and antioxidant enzyme activity. This study included 36 pemphigus vulgaris and 42 pemphigus foliaceus patients as well as a group of controls consisting of 78 healthy volunteers. Malondialdehyde levels (p < 0.001) and catalase activity (p < 0.001) are higher in both groups of patients than in the control group. The two groups of patients showed a nonsignificant decrease in the thiol groups compared with the healthy one. A nonsignificant difference was shown between pemphigus vulgaris and pemphigus foliaceus patients, except for the catalase which shows an increase in the pemphigus vulgaris group. We have also found significant correlations between serum oxidative stress marker levels and serum anti-desmoglein antibody levels in the two pemphigus groups. These findings underline the implication of oxidative stress in the physiopathology of pemphigus by the increase in the autoantibodies' reactivity.

Isotretinoin treatment induces oxidative toxicity in blood of patients with acne vulgaris: a clinical pilot study

Acne vulgaris is the one of the most common skin diseases. Although isotretinoin (13-cis-retinoic acid) is an effective and well-tolerated medication, it has a wide range of side effects. Because the effects of isotretinoin on oxidant and antioxidant systems have not yet been clarified, we investigated plasma and erythrocyte antioxidant vitamins, lipid peroxidation (LP), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values in patients with acne vulgaris before and after isotretinoin treatment. The study was performed on the blood plasma and erythrocytes of 31 acne vulgaris patients. Blood samples were taken from the patients before treatment and after isotretinoin (oral and 0·5-0·7 mg·kg(-1)) treatment for 2 months. Plasma amtioxidant vitamins, erythrocyte malondialdehyde, GSH and GSH-Px levels were measured. Plasma vitamin E (p < 0·001), lipid peroxidation (LP) and serum high-density lipoprotein cholesterol (p < 0·001) values were significantly lower in the treatment group than in the pre-treatment group, although erythrocyte LP (p < 0·001), GSH (p < 0·01) and GSH-Px (p < 0·001), aspartate aminotransferase (p < 0·05), alanine aminotransferase (p < 0·05), density lipoprotein cholesterol (p < 0·001) and total cholesterol (p < 0·01) levels were significantly higher in the treatment group than in the pre-treatment group. Vitamins A, C and β-carotene concentrations did not change significantly between the two groups. In conclusion, the results of the current study indicate that isotretinoin treatment induces oxidative stress and liver damage by decreasing plasma vitamin E and increasing erythrocytes GSH-Px, GSH and liver enzyme values.

Ocular Behçet disease: current therapeutic approaches

PURPOSE OF REVIEW

To alert physician to timely recognition and current treatment of recurrent hypopyon iridocyclitis or panuveitis in ocular Behçet disease (OBD).

RECENT FINDINGS

Interferon-α, rituximab, intravitreal triamcinolone, and biological response modifiers by tumor necrosis factor inhibitors such as infliximab and adalimumab are being used increasingly for the treatment of severe sight-threatening ocular inflammation including retinal vasculitis and cystoid macular edema (CME).

SUMMARY

Biological agents offer tremendous potential in the treatment of OBD. Given that OBD predominantly afflicts the younger adults in their most productive years, dermatologist, rheumatologist, internist, or general practitioners supervising patients with oculo-articulo-oromucocutaneous syndromes should be aware of systemic Behçet disease. Early recognition of ocular involvement is important and such patients should strongly be instructed to visit immediately an ophthalmologist, as uveitis management differs from extraocular involvements with high ocular morbidity from sight-threatening complications due to relapsing inflammatory attacks in the posterior segment of the eye. A single infliximab infusion should be considered for the control of acute panuveitis, whereas repeated long-term infliximab infusions were proved to be more effective in reducing the number of episodes in refractory uveoretinitis with faster regression and complete remission of CME.

17β-Estradiol and vitamin E modulates oxidative stress-induced kidney toxicity in diabetic ovariectomized rat

The aim of this study was to investigate the effects of vitamin E (alpha-tocopherol) and 17β-estradiol (E(2)) supplementation on malondialdehyde (MDA), glutathione (GSH), vitamin A, beta carotene, selenium-dependent glutathione peroxidase (GSH-Px), zinc-dependent superoxide dismutase (SOD), and copper/zinc-dependent catalase (CAT) values in the kidney of ovariectomized (OVX) diabetic rats. Forty-two female rats were randomly divided into seven equal groups as follows: group I, control; group II, OVX; group III, OVX+E(2); group IV, OVX+E(2)+alpha-tocopherol; group V, OVX+diabetic; group VI, OVX+diabetic+E(2); and group VII, OVX+diabetic+E(2)+alpha-tocopherol. E(2) (40 μg kg(-1)/day) and alpha-tocopherol (100 μg kg(-1)/day) were given. Bilateral ovariectomy was performed in all groups except group I. After 4 weeks, antioxidant and MDA levels in the kidney for all groups were analyzed. GSH-Px, CAT, SOD, GSH levels, vitamin A, and beta carotene levels were decreased in OVX group compared to those in the control group but MDA level was elevated via ovariectomy. However, E(2) and E(2)+alpha-tocopherol supplementations in OVX group was associated with an increase in the GSH-Px, GSH, CAT and Zn-SOD values, vitamin A, and beta carotene levels but a decrease in MDA levels in kidney. The MDA levels in the kidney of diabetic OVX rats were found higher than those in the control and OVX groups. However, GSH, GSH-Px, CAT, SOD, vitamin A, and beta carotene levels in kidney were lower in OVX diabetic rats. On the other hand, E(2) and E(2)+alpha-tocopherol supplementations to OVX diabetic rats have caused an increase in GSH-Px, CAT and SOD, GSH, vitamin A, and beta carotene levels but a decrease in MDA levels. In conclusion, the E(2) and E(2)+alpha-tocopherol supplementations to diabetic OVX and OVX rats may strengthen the antioxidant defense system by reducing lipid peroxidation, and therefore they may play a role in preventing renal disorders.

Colchicine modulates oxidative stress in serum and neutrophil of patients with Behçet disease through regulation of Ca²⁺ release and antioxidant system

Behçet disease (BD) is a chronic, inflammatory, and multisystemic condition with an uncertain pathogenesis. One of the major immunologic findings in BD pathogenesis is increase in activity of neutrophil. An increase in the cytosolic free Ca²⁺[Ca²⁺](i) concentration that induces Ca²⁺ signaling is an important step that participates in the neutrophil activation and reactive oxygen species production that leads to tissue damage in body cells. We aimed to investigate the effects of colchicine on oxidative stress and Ca²⁺ release in serum and neutrophil of BD patients with active and inactive periods. Twelve Behçet patients (6 active and 6 inactive) and 6 control subject were included in the study. Disease activity was considered by clinical findings. Serum and neutrophil samples were obtained from the patients and control subjects. Neutrophils from patients with active BD were divided into three subgroups and were incubated with colchicine, verapamil + diltiazem, and colchicine + verapamil + diltiazem, respectively. Erythrocyte sedimentation rate, leucocytes counts, serum C-reactive protein, neutrophil, and serum lipid peroxidation and intracellular Ca²⁺ release levels were higher in active and inactive groups than in the control group, although their levels were lower in active group than in inactive group. However, neutrophil Ca²⁺ release levels were decreased in colchicine, verapamil + diltiazem, and colchicine + verapamil + diltiazem groups group compared to active group. Serum glutathione, vitamin A, vitamin E, and β-carotene concentrations were lower in active and inactive groups than in the control group, although serum vitamin E and β-carotene concentrations were higher in the inactive group than in the active group. Neutrophil and serum glutathione peroxidase activity within the three groups did not change. In conclusion, we observed the importance of Ca²⁺ influx into the neutrophils and oxidative stress in the pathogenesis and activation of the patients with BD. Colchicine induced protective effects on oxidative stress by modulating Ca²⁺ influx in BD patients.

Vitamins C and E treatment combined with exercise modulates oxidative stress markers in blood of patients with fibromyalgia: a controlled clinical pilot study

We aimed to investigate effects of vitamins C and E (VCE) supplementation with exercise (EX) on antioxidant vitamin and lipid peroxidation (LP) levels in blood of patients with fibromyalgia (FM). A controlled study was performed on blood samples from 32 female FM patients and 30 age-matched controls. The patients were divided into three groups namely EX (n = 10), VCE (n = 11), and EX plus VCE (n = 11) after taking basal blood samples. After 12 weeks of EX and VCE supplementation, blood samples were taken once more from the patients. LP levels in plasma and erythrocytes were higher in the patients at baseline than those in controls, whereas LP levels were lower in the VCE and EX groups at the end of 12 weeks than those at baseline. Plasma concentrations of vitamins A and E and reduced glutathione were lower in the patients than those in controls and their concentrations were increased by VCE and EX. Glutathione peroxidase activity in erythrocytes was increased by VCE supplementation, with or without EX. Concentrations of β-carotene in the groups did not change with treatment. Despite the measured effects on anti-oxidative mechanisms, FM symptoms were not improved by the treatments. In conclusion, VCE with EX may protect against FM-induced oxidative stress by up-regulation of an antioxidant redox system in the plasma and erythrocytes of patients with FM. Such protective effects of VCE in the patients seemed to be greater in combination with EX than EX alone.

The effects of 17beta-estradiol and vitamin E treatments on oxidative stress and antioxidant levels in brain cortex of diabetic ovariectomized rats

We investigated the effects of 17beta-estradiol (E 2 ) and vitamin E on lipid peroxidation and antioxidant levels in brain cortex of diabetic ovariectomized (OVX) rats. Forty-two rats were equally divided into seven groups: Control; OVX; OVX+E 2 ; OVX+E 2 +vitamin E; OVX+diabetic; OVX+diabetic+E 2 and OVX+diabetic+E 2 +vitamin E. Then, E 2 (40 microg kg -1 /day) and vitamin E (100 mg kg -1 /day) were given. Glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), vitamin A and beta-carotene in brain were decreased (p<0.05) when compared with control in OVX but MDA in brain and glucose in plasma were elevated (p<0.05). The antioxidant levels in brain (p<0.05) increased although MDA (p<0.05) in brain and glucose (p<0.05, p<0.01) in plasma decreased in OVX after E 2 and E 2 +vitamin E supplementation. The activities of GSH-Px (p<0.001, p<0.01), CAT (p<005, p<0.001) and SOD (p<0.001) and the levels of GSH (p<0.001), vitamin A (p<0.05) and beta-carotene (p<0.001, p<0.05) were lower in the brain of OVX diabetic rats, while MDA in the brain and glucose in the plasma were higher (p<0.001). The antioxidant enzymes (p<0.05, p<0.01), GSH, vitamin A and beta-carotene (p<0.01, p<0.001) in brain increased while MDA in brain and glucose in plasma decreased (p<0.01, p<0.001) in diabetic OVX after treatments. Finally, the E 2 and E 2 +vitamin E supplementation to diabetic OVX and OVX rats may strengthen the antioxidant system by reducing lipid peroxidation.

Protective effects of selenium and vitamin E combination on experimental colitis in blood plasma and colon of rats

Ulcerative colitis increases oxidative damage accompanied by production of free oxygen radicals. Selenium (Se) and vitamin E are two natural antioxidants. The present study was undertaken to investigate the possible protective role of Se and vitamin E combination in experimental colitis induced by acetic acid (AA) in rats. This study was carried out on three groups, namely the first (control), the second (experimental colitis group, 2 ml 5% acetic acid), and the third groups (2 ml 5% acetic acid, vitamin E (100 mg/kg body weight (bw)) plus Se (0.2 mg/kg bw)). The activities of catalase (CAT), prolidase (PRS), myeloperoxidase (MPO), total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), total thiol (T-SH) were determined in plasma and colon samples. Macroscopic and microscopic damages in colon were increased by AA treatment (p < 0.01 and p < 0.01, respectively), whereas they were decreased by selenium and vitamin E treatment (p < 0.05 and p < 0.01, respectively). The activities of CAT and PRS in the plasma and colon were significantly affected (p < 0.05 and p < 0.01) by treatment of AA, Se, and vitamin E. MPO activity in colon was increased (p < 0.01) by AA treatment and decreased (p < 0.05) by Se and vitamin E administration. The values of TOS and OSI in plasma were increased (p < 0.5) by AA. The TAC and T-SH in colon were decreased (p < 0.05) by AA and increased (p < 0.05) by Se and vitamin E. Based upon these results, Se and vitamin E may play an important role in preventive indication of the oxidative damage associated by acetic acid caused inflammation.

Vitamin levels in Behçet's disease

OBJECTIVE

To determine the role of oxidative stress and the antioxidant defense mechanism in the etiopathogenesis of active and inactive Behçets disease. In line with this objective, the present study aimed to examine the levels of nitric oxide (NO) and malondialdehyde (MDA), which are the end products of oxidant stress, and vitamins, which are non-enzymatic antioxidants, for the diagnosis and particularly the follow-up of Behçet's disease.

MATERIALS AND METHODS

The study group consisted of a total of 60 individuals: 40 of whom were Behçet's disease patients and 20 were healthy individuals. Of the 40 Behçet's patients, 29 had the active and 11 had the inactive (stable) form of the disease.

RESULTS

Although plasma MDA and NO (its stable form nitrite) levels in the total patient group were statistically significantly higher than those in the control group (p<0.06), there was no statistically significant difference as such between inactive Behçet's patients and the control group (p>0.05). Vitamin E, C, B1, B2 and flavin mononucleotide (FMN) values were significantly lower in the patient group in comparison with the control group (p<0.05). There was no statistically significant difference in other vitamin values.

DISCUSSION

It is contemplated that measurement of such oxidative stress factors as MDA and NO and an accompanying evaluation of the antioxidant defense system can be significant in the diagnosis and treatment follow-up of Behçet's disease.

Is there any relationship between serum and urine neopterin and serum interferon-gamma levels in the activity of Behcet's disease?

BACKGROUND

Behcet's disease (BD) is a chronic, inflammatory, multisystem vasculitic disorder. There is no reliable laboratory marker that indicates disease activity. Neopterin is an immunological marker of cellular immune activation, which is secreted by monocytes/macrophages as a result of interferon-gamma (IFN-gamma) secretion by activated T lymphocytes.

OBJECTIVE

We aimed to investigate serum and urine neopterin levels in BD patients.

METHODS

Forty-five patients who were diagnosed according to the criteria of the International Study Group for BD and 45 age- and sex-matched healthy controls were enrolled in the study. Disease activity was considered by clinical findings. Serum and urine neopterin levels and serum IFN-gamma levels were measured.

RESULTS

The mean values of serum and urine neopterin levels were 12.68 +/- 4.87 nmol/L and 167.53 +/- 148.73 micromol/mol creatinine, respectively, in BD patients (P = 0.000 and P = 0.008, respectively), which were statistically significantly different from the control group. However, there was no significant statistical difference between serum and urine neopterin levels of the clinically active and inactive patients. It was also found that the mean value of serum IFN-gamma levels was higher in healthy controls than in BD patients (P = 0.000).

CONCLUSIONS

We conclude that serum and urinary neopterin measurement can not be used as a reliable laboratory marker as the BD patients' serum and urinary neopterin levels do not increase in the active stage even though these levels increase when compared to healthy controls.

Caffeic acid phenethyl ester modulates methotrexate-induced oxidative stress in testes of rat

The aim of this study was to investigate the possible protective role of caffeic acid phenethyl ester on testicular toxicity of methotrexate in rats. Nineteen male rats were divided into three groups as follows: group I, control; group II, methotrexate-treated; group III, methotrexate + caffeic acid phenethyl ester-treated. In the second day of experiment, a single dose of methotrexate was intraperitoneally administered to groups II and III, although a daily single dose of caffeic acid phenethyl ester was intraperitoneally administered to group III for 7 days. At the end of the experiment, the testes of the animals were removed and weighed. In the tissue, the level of lipid peroxidation as malondialdehyde and activities of superoxide dismutase were higher in the methotrexate group than in the control group. Lipid peroxidation levels and superoxide dismutase activities were decreased in caffeic acid phenethyl ester + methotrexate group compared with methotrexate group. The activities of catalase in the methotrexate group decreased insignificantly although its activities were significantly increased by caffeic acid phenethyl ester administration. The activity of glutathione peroxidase did not change in the groups. There was significant difference in body weight between control and methotrexate-induced groups. In conclusion, the administration of methotrexate causes elevation of oxidative stress although treatment with caffeic acid phenethyl ester has protective effects on the oxidative stress in testes.

Oxidative stress: correlation with Behçet's disease duration, activity and severity

OBJECTIVE

To study the oxidant/antioxidant status in Behçet's disease (BD) patients and the potential link between antioxidant enzymatic defences impairment and the disease duration, activity and severity.

METHODS

40 BD patients (27 males, 13 females; mean age: 38.8 years) were prospectively enrolled in the study and compared to a sex and age matched control group. Plasma malondialdehyde (MDA), the reduced glutathione (GSH)/oxidised glutathione (GSSG) ratio, erythrocyte superoxide dismutase, catalase and glutathione peroxidase (GSH-PX) were analysed in both groups. A correlation analysis was performed between these parameters and disease duration, activity and severity. Activity and severity of BD were assessed meaning two respective clinical scores.

RESULTS

When compared to controls MDA was increased and GSH/GSSG reduced in BD patients (respectively p<0.005). Superoxide dismutase (SOD) was significantly lower while catalase was significantly higher in BD than in controls. Correlation analysis showed that SOD activity was significantly and negatively correlated to disease duration and activity but not to severity. Other oxidant/antioxidant markers were not significantly linked to neither disease duration nor activity and severity.

CONCLUSION

Our study confirm the existence of an oxidative stress (OS) state in BD as shown by the increase of MDA and the diminution of GSH/GSSG ratio which can be used as another index of OS. Despite this OS state, the activity of antioxidant enzymes and especially of SOD is impaired and negatively correlated to the disease duration and activity. We think that a rational strengthening of antioxidant defences should be part of an optimal treatment strategy.

Traitements actuels et perspectives thérapeutiques dans la maladie de Behçet

Behçet disease is a multisystem inflammatory disorder, the cause of which remains unclear. Vasculitis is its predominant histopathological feature. It remains a source of significant morbidity in affected patients, many of whom become blind. Treatment of its various manifestations remains controversial today because of the paucity of randomized controlled trials and the absence of standardized outcome measures for this disease. The preferred treatment modalities combine different drugs, including topical therapies as well as systemic corticosteroids, NSAIDs, colchicine, and immunosuppressive and cytotoxic agents. The principal objectives are always relief of symptoms, control of inflammatory eye disease, suppression of systemic inflammation and vasculitis and prevention of recurrences and thus of irreversible damage. Although the prognosis of various manifestations of Behçet disease has improved, many patients still have refractory disease that requires treatment with combinations of various immunosuppressants, cytotoxic agents, and corticosteroids, which may lead to serious infections or secondary malignancy. Recent improvements in our understanding of the pathogenic mechanisms of Behçet disease, especially its molecular basis, have led to a new generation of potential treatments with improved side-effect profiles and more specific immune targeting. These include new immunosuppressants, biologic medicines, tolerizing agents and immunoablation techniques. Until randomized controlled studies with these agents are conducted, however, no final judgment about their usefulness is possible.

Oxidative stress in patients with Behcet's disease: I correlation with severity and clinical parameters

The study was designed to investigate the possible correlation between some oxidative stress parameters in Behcet's disease and the clinical manifestations of the disease as well as the possible correlation with the disease severity. Seventy-six patients diagnosed according to the International Study Group criteria for Behcet's disease were included in the study. Sixty patients had mild-to-moderate disease and 16 patients had severe disease. Sixty matched control subjects were also included. After a full history and examination from each subject, 10 mL blood was drawn from each for analysis. Serum malondialdehyde, glutathione, ceruloplasmin, copper and zinc levels were determined. Patients with Behcet's disease showed increased levels of serum malondialdehyde and copper while glutathione and zinc levels were decreased. Comparison between these parameters in patients with mild-to-moderate disease with those with severe disease showed only that serum zinc levels were lower in severe Behcet's disease. Serum malondialdehyde levels were found to be significantly positively correlated with oral ulcer size, duration and frequency. Glutathione levels were found to be inversely correlated with the clinical manifestation index and all oral ulcer parameters. Zinc levels were found to be inversely correlated with the clinical manifestation index and pathergy test positivity grades. Copper levels were found to be positively correlated with oral ulcer number. Although the parameters of oxidative stress did not show correlation with disease severity, they were correlated with the disease manifestations. This points out the importance of oxidative stress in Behcet's disease.

Protective Effects of Lamotrigine, Aripiprazole and Escitalopram on Depression-induced Oxidative Stress in Rat Brain

We investigated the effects of lamotrigine, aripiprazole and escitalopram administration and experimental depression on lipid peroxidation (LP) and antioxidant levels in cortex of the brain in rats. Forty male wistar rats were randomly divided into five groups. First group was used as control although second group was depression-induced group. Aripiprazole, lamotrigine and escitalopram per day were orally supplemented to chronic mild stress (CMS) depression-induced rats constituting the third, fourth and fifth groups for 28 days, respectively. Depression resulted in significant decrease in the glutathione peroxidase (GSH-Px) activity, reduced glutathione and vitamin C of cortex of the brain although their levels and beta-carotene concentrations were increased by the three drugs administrations to the animals of CMS induced depression group. The LP levels in the cortex of the brain and plasma of depression group were elevated although their levels were decreased by the administrations. The increases of antioxidant values in lamotrigine group were higher according to aripiprazole and escitalopram supplemented groups. Vitamin A level did not change in the five groups. In conclusion, the experimental depression is associated with elevated oxidative stress although treatment with lamotrigine has most protective effects on the oxidative stress within three medicines.

Venlafaxine Modulates Depression-Induced Oxidative Stress in Brain and Medulla of Rat

Venlafaxine is an approved antidepressant that is an inhibitor of both serotonin and norepinephrine transporters. Medical treatment with oral venlafaxine can be beneficial to depression due to reducing free radical production in the brain and medulla of depression-induced rats because oxidative stress may a play role in some depression. We investigated the effect of venlafaxine administration and experimental depression on lipid peroxidation and antioxidant levels in cortex brain, medulla and erythrocytes of rats. Thirty male wistar rats were used and were randomly divided into three groups. Venlafaxine (20 mg/kg) was orally supplemented to depression-induced rats constituting the first group for four week. Second group was depression-induced group although third group was used as control. Depressions in the first and second groups were induced on day zero of the study by chronic mild stress. Brain, medulla and erythrocytes samples were taken from all animals on day 28. Depression resulted in significant decrease in the glutathione peroxidase (GSH-Px) activity and vitamin C concentrations of cortex brain, glutathione (GSH) value of medulla although their levels were increased by venlafaxine administration to the animals of depression group. The lipid peroxidation levels in the three tissues and nitric oxide value in cortex brain elevated although their levels were decreased by venlafaxine administration. There were no significant changes in cortex brain vitamin A, erythrocytes vitamin C, GSH-Px and GSH, medulla vitamin A, GSH and GSH-Px values. In conclusion, cortex brain within the three tissues was most affected by oxidative stress although there was the beneficial effect of venlafaxine in the brain of depression-induced rats on investigated antioxidant defenses in the rat model. The treatment of depression by venlafaxine may also play a role in preventing oxidative stress.

Oxidative status of DBA/1J mice with type II collagen-induced arthritis

The present study was undertaken to compare the oxidant statuses of mice with collagen-induced arthritis (CIA) and those of healthy mice. For this purpose, serum oxidant products and arthritic profiles were measured in DBA/1J mice with CIA. In addition, the levels of oxidation products and the activities of antioxidant enzymes were determined in liver, heart, spleen, kidney, lung and brain. The induction of arthritis significantly increased anti-collagen antibody, rheumatoid factor, interleukin (IL)-1beta, IL-6, protein carbonyl (PCO), advanced glycation end-products (AGE), malondialdehyde (MDA) and low density lipoprotein (LDL)-cholesterol levels in serum (P < 0.05). CIA in DBA/1J mice was associated with significantly lower activities of superoxide dismutase, glutathione peroxidase and glutathione reductase in spleen but higher levels of oxidation products in spleen, kidney and liver than healthy normal mice (P < 0.05). However, lower concentrations of oxidized protein and higher activities of antioxidant enzymes were observed in CIA mouse lung and brain than in healthy normal mice. Dexamethasone treated CIA mice had decreased arthritis-related indices and showed: reduced PCO and AGE in spleen and brain, and increased PCO and AGE in heart, kidney and lung; increased MDA in heart, spleen, lung and brain; reduced SOD and GR activities in lung and brain; increased GPx activity in spleen and brain; and increased GR activity heart and spleen. These data suggest that mice with CIA were more susceptible to oxidative damage in the spleen and liver under the chronic inflammatory conditions.

Assessment of homocysteine, neopterin and nitric oxide levels in Behcet's disease

BACKGROUND

Behçet's disease is a multisystemic immunoinflammatory disease with a wide variety of clinical manifestations, whereas recurrent aphthous stomatitis is a local oral disease. The aim of this study was to examine the distribution of homocysteine levels in patients with active Behçet's disease, possible association of homocysteine with nitric oxide and neopterin levels, and to characterize the differences between patients with Behçet's disease and those with recurrent aphthous stomatitis in terms of these parameters compared with healthy controls.

METHODS

A total of 23 patients with active Behçet's disease, 25 patients with recurrent aphthous stomatitis as positive controls, and 21 healthy subjects were included in this study. Serum homocysteine and neopterin levels were measured flourimetrically by HPLC. Serum nitric oxide production was assayed by measuring total nitrite levels with Griess reagent.

RESULTS

Significantly higher homocysteine (12.9+/-3.3 micromol/L) and lower nitric oxide (41.5+/-10.9 micromol/L) and neopterin (6.4+/-1.0 nmol/L) levels were observed in patients with Behçet's disease compared with healthy controls (10.7+/-2.0 micromol/L, 49.7+/-16.2 micromol/L, 8.7+/-2.2 nmol/L, respectively) (p<0.03 for neopterin, p<0.04 for homocysteine and nitric oxide). However, homocysteine, nitric oxide, biopterin and neopterin levels and the neopterin/biopterin ratio for recurrent aphthous stomatitis patients were not significantly different compared to healthy controls. A significant positive correlation was observed between serum homocysteine and serum neopterin/biopterin ratio in patients with Behçet's disease (r=0.975, p<0.005).

CONCLUSIONS

In contrast to recurrent aphthous stomatitis, there is a higher prevalence of hyperhomocysteinemia in Behcet's disease. Homocysteine may have deleterious effects on the pathology of Behcet's disease by decreasing nitric oxide levels and interfering with the immune system.

Oral zinc sulfate in the treatment of Behcet's disease: A double blind cross-over study

This was a randomized, controlled, double-blind trial of zinc sulfate in the treatment of Behcet's disease. Patients with Behcet's disease were recruited in this study between November 2001 and February 2003. A clinical manifestations index (CMI) was calculated for each patient. Serum zinc was estimated in all patients both at the beginning and monthly throughout the trial. Serum zinc levels were estimated from 30 healthy normal subjects matched for age and sex as a control group. Patients were randomly allocated to receive either 100 mg zinc sulfate or identical placebo tablet three times daily in a double-blind manner. After 3 months of starting treatment, patients were crossed over, that is, patients on placebo received zinc sulfate and vice versa. Mean serum zinc level in Behcet's disease patients was statistically significantly lower than mean serum zinc levels in healthy the control. In group A (started with zinc sulfate), the mean CMI started to decline directly after the first month of therapy with zinc sulfate to significantly lower levels. After shifting to placebo treatment in the fourth month, the mean of CMI started to rise again gradually but remained significantly lower than levels before therapy for the fourth and fifth months. In group B (started with placebo), the mean of CMI remained high for the first 3 months. After crossing over to zinc sulfate in the fourth month, the mean of CMI started to decrease after the fourth month. An inverse correlation between CMI and serum zinc level was found. No side-effects were seen in either group. In conclusion, zinc sulfate was found to be a good option in the treatment of Behcet's disease.

The association between total antioxidant status and oxidative stress in Behçet’s disease

There has recently been growing evidence supporting the importance of oxidative stress in the pathogenesis of Behçet's disease (BD). In this study, we aim to evaluate total antioxidant status (TAS) and total oxidative stress (TOS) in BD patients, and compare their results both with controls that had recurrent aphthous stomatitis (RAS) and healthy controls. TAS statistically decreased in RAS patients, and TOS levels increased in BD and RAS patients than those in healthy controls. The serum levels of Cu significantly increased only in BD patients when compared with healthy controls. Fe levels were not statistically different among the BD patients, RAS patients and healthy controls, but there was a positive correlation between TOS and plasma Fe levels in BD patients. Our results suggest that there is an insufficient antioxidant system and increased oxidative status both in BD and RAS patients. The antioxidant supplementations in addition to medical treatments will improve the quality of life.

Protective role of alpha-tocopherol on retinal injury in experimental uveitis in guinea pigs

PURPOSE

PURPOSEof the study was to determine whether alpha-tocopherol (AT) can protect the retina from oxidative damage in experimental uveitis (EU).

MATERIAL AND METHODS

The eyes of 36 adult male guinea pigs were studied. The guinea pigs were divided into three groups of 12 animals each. The first group was used as control. The right eyes of groups 2 and 3 received an intravitreal injection of bovine serum albumin for EU induction. At the same time and also on the consecutive third and fifth days, group 3 received intraperitoneal AT injections. The samples were collected on the eighth day. Retinal malondialdehyde (MDA) levels and the average thickness of the inner plexiform layer were measured and the histopathology of the eyes was studied.

RESULTS

The MDA level was significantly lower in the control group than in the groups 2 (p<0.01) and 3 (p<0.05). When compared with the EU group 2, there was a significant lowering of MDA in the AT injected group 3 (p<0.01). The thickness of the inner plexiform layer in the control group 1 was significantly lower than in the other groups (p<0.01). Its thickness in the group 3 supplied with AT was significantly lower than in the group 2 (p<0.01).

CONCLUSIONS

The data indicate that intraperitoneal AT administration protects against EU injury in the guinea pig retina as evidenced by the reduced MDA and the thickness of retina.

Comparative study of antioxidant enzymes in tissues surrounding implant in rabbits

There is a possible role of reactive oxygen species (SROS) in the complication of implants although there is presently little information. The aim of this study was to investigate the alterations in lipid peroxidation (LP) and antioxidant enzyme activities in tissues surrounding implants in rabbits. Thirty New Zealand albino male rabbits were used. They were randomly divided into five groups. The first group (I) was used as control. Groups II, III, IV and V were implanted with stainless steel, ceramic, titanium and polyethylene, respectively. One month after the administration of implant, the tissues surrounding the implant were carefully removed for antioxidant enzyme analysis. Glucose-6-phosphate dehydrogenase (G6PD), glutathione reductase (GR), superoxide dismutases (SOD), glutathione peroxidase (GPx), catalase (CAT) in tissues surrounding the implants in the groups II, III and IV were significantly (p<0.05-p<0.001) lower than in the control group although glutathione S-transferase (GST) activities and LP values were increased. CAT activity and LP level did not decrease in group V. In conclusion, these data demonstrate that there is an increase in lipid peroxidation in the tissues surrounding ceramic and titanium implants of animals whereas there is a decrease in antioxidant enzymes. Oxidative stress plays a very important role in the complications of ceramic and titanium implants. The polyethylene implant seems to be the best of the four implant materials tested.

Effects of intraperitoneal vitamin E, melatonin and aprotinin on leptin expression in the guinea pig eye during experimental uveitis

PURPOSE

To observe ultrastructural changes and leptin expression in the guinea pig eye during experimental uveitis (EU) and the effects of vitamin E, melatonin and aprotinin on leptin expression.

METHODS

Thirty male guinea pigs were randomly classified into five groups. Group 1 was the control group. Groups 2, 3, 4 and 5 received intravitreal injections of bovine serum albumin (BSA) to induce EU. At the same time on the third day, groups 3 (EU + vitamin E), 4 (EU + melatonin) and 5 (EU + aprotinin) received intraperitoneal vitamin E (150 mg/kg), melatonin (10 mg/kg) and aprotinin (20,000 IU/kg), respectively. On the sixth day, histopathological and clinical scoring of inflammation were performed, and leptin expression was investigated in the retina, choroid, sclera, episclera and cornea, and compared.

RESULTS

There was a remarkable increase in leptin expression in the retina, choroid, sclera and episclera in the EU group. Leptin expression in the treatment groups was similar to that in the control group. At light and electron microscopic levels, ganglion cells were oedematous and inner plexiform layer thickness had increased in the EU group retinas. Oedema was decreased in the treatment groups. Comparison of the EU and treatment groups revealed significant differences histopathologically and clinically.

CONCLUSION

Experimental uveitis causes an increase in leptin expression in the retina, choroid, sclera and episclera of guinea pigs. Vitamin E, melatonin and aprotinin inhibit this increase. Leptin seems to be closely related to ocular inflammation.

Evaluation of the association between null genotypes of glutathione-S-transferases and Behcet’s disease

Glutathione S-transferases (GST) play an important role in oxidative stress related syndromes. An imbalance of the oxidant and antioxidant systems is important in the pathogenesis of Behcet's disease (BD). The objective of this study was to evaluate the association of null genotypes of GST-M1 and GST-T1 with BD since some preliminary molecular genetic data were recently published. Ninety-four Turkish BD patients (42 male, 52 female, 37.1+/-10.4 years) and 140 healthy volunteers (70 male, 70 female, 36.8+/-11.7 years) matched for age and gender with the patients as the control group were included in the study. Distributions of GST-M1 and GST-T1 genotypes were determined by multiplexed PCR using three sets of primers for GST-M1, GST-T1, and beta-globulin genes. There was no association between BD and the frequencies of GST-M1 and GST-T1 null genotypes when compared to controls by separate analysis. However, by cross and pooled combination analysis there was a significant association between the frequencies of pooled GSTs with one or both null genotypes in BD and controls. This is the first evidence that the association between the frequencies of GST-M1 and GST-T1 null genotypes and BD might be dependent on the interaction of multiple null allele polymorphisms rather than a single null allele of GST-M1 and GST-T1.

Antioxidant effects of alpha-, gamma- and succinate-tocopherols in guinea pig retina during ischemia-reperfusion injury

The purpose of this study is to investigate the efficacy of alpha-tocopherol (AT), gamma-tocopherol (GT) and d-alpha-tocopherol polyethylene glycol 1000 succinate (TPGS) in preventing the retinal injury followed by ischemia-reperfusion (IR). The eyes of 40 adult male guinea pigs were used in the study. The guinea pigs were divided into five groups of eight rats each. First and second groups were used as control and IR groups, respectively. Third, fourth and fifth groups received subcutaneously AT, GT and TPGS, respectively. Treatment with each vitamin was performed before 5min of ischemia with reperfusion at 6h intervals for three times. Retinal ischemia was induced for 90min, then followed by reperfusion for 24h. The animals were killed at 24h of reperfusion. Lipid peroxidation (LP) and glutathione (GSH) levels were measured in right retinas by using a spectrofluorometer. Retinal GSH levels were found significantly lower (p < 0.002) in the IR group than in control group and there was a significant increase in the LP levels in IR group (p < 0.001). The decrease of GSH and increase of LP levels in the IR animals were significantly (p < 0.05 and 0.001) improved by the administration of the Vitamin E forms. When compared to GT group, there were no significant differences in LP levels in AT and TPGS groups. However, LP level in AT group was significantly (p < 0.01) lower than in the TPGS group. The GSH levels were higher (p < 0.001) in AT and TPGS groups than in IR group. Therefore, modulator effect of AT and GT were greater than that of TPGS. In conclusion, present data demonstrate that there is an increase in the LP in the retina of IR-induced animals and a decrease in the GSH levels. However, subcutaneous AT, GT and TPGS were effective in preventing retinal injury followed by ischemia-reperfusion. The subcutaneous AT may play a role in treating IR injury.

Increased advanced oxidation protein products in Behçet's disease: a new activity marker?

BACKGROUND

Behçet's disease (BD) is a chronic inflammatory disease with unknown pathogenesis. As various functions of neutrophils in peripheral blood, such as chemotaxis, phagocytosis and generation of reactive oxygen species (ROS) increase in BD, ROS-mediated oxidative stress related to neutrophil activation may have an important role in the pathogenesis of BD.

OBJECTIVES

To investigate the importance of neutrophil activation as the main source of oxidative stress through protein oxidation in the pathogenesis of BD, and also to investigate whether one of the products of protein oxidation, advanced oxidation protein products (AOPP), may be used as an activity marker for BD.

METHODS

Patients with BD (n = 49), at active and inactive stages, with or without evidence of uveitis, and healthy volunteers (n = 40) were entered into the study. A full blood count, peripheral blood smears, routine biochemical analyses, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) measurements were performed in all patients preceding the study. Plasma myeloperoxidase (MPO) activity, representing neutrophil activation, and biomarkers of oxidative stress reflecting protein oxidation, such as levels of AOPP and thiol, were measured spectrophotometrically. Statistical comparisons were made using Mann-Whitney U-tests, Student's t-tests, anova/post-anova tests and correlation analyses.

RESULTS

In all patients, the results of full blood count, peripheral blood smears and routine biochemical analyses were in the normal range, but mean values of CRP and ESR were higher than laboratory reference values. Plasma MPO activity and AOPP levels were found to be higher and thiol values lower in the total patient group and individual subgroups than in controls. Patients with active BD had significantly higher MPO and AOPP levels and lower thiol levels than patients with inactive BD. There was no difference between uveitis-positive and uveitis-negative subgroups in MPO and thiol levels, but AOPP levels were lower in the latter group. Patients with active BD +/- uveitis were shown to have increased MPO and AOPP but decreased thiol levels in comparison with the inactive BD, uveitis-negative subgroup. There were strong positive correlations between ESR and CRP, ESR and MPO, ESR and thiol, ESR and AOPP, CRP and MPO, CRP and AOPP, MPO and AOPP, and thiol and AOPP levels in patients with BD.

CONCLUSIONS

Based on this first study, in which MPO-mediated AOPP formation has been demonstrated, it may be suggested that activated neutrophils may play an important role in the pathogenesis of BD and that chlorinated oxidants of neutrophil origin may lead to oxidative stress, notably protein oxidation. Therefore, AOPP may be a useful marker for monitoring the progress and the severity of the disease activity.

Administration of high dose intravitreal melatonin degenerates retinal cells in guinea pigs

The purpose of this study was to investigate the influence of intravitreally injected different doses of melatonin on retinal morphology. The right eyes of 35 male albino guinea pigs were used. The animals were classified randomly into five groups in equal numbers. First group was used as control and received intravitreal injection of placebo. Groups 2, 3, 4 and 5 received intravitreally injections of melatonin at 50, 100, 150 and 200microg/body weight (BW) each, respectively. The animals were sacrificed 15 days after the injections. The eyes were enucleated and processed for light microscopic evaluation. Intravitreal injection of melatonin at doses ranging from 50 to 150microg did not induce morphological changes, although a higher thickness of the inner plexiform layer (IPL) was found in Group 5 compared to other groups (p < 0.05). The mean retinal ganglion cell (RGC) counts were found to be lower in Group 5 compared to other groups (p < 0.05). Our findings indicate that intravitreal injection of melatonin at doses ranging from 50 to 150microg/BW does not induce morphological changes. The dose of 200microg/BW produced significant damage including retinal ganglion cell loss and formation of retinal edema.

Effects of testosterone and vitamin E on the antioxidant system in rabbit testis

The aim of the study was to investigate the effects of testosterone propionate and vitamin E on the antioxidant system in the testis. Thirty-two male New Zealand White rabbits were randomly divided into four groups. The first group was used as control. The second group was injected with testosterone propionate, the third group vitamin E and the fourth group vitamin E and testosterone propionate combination. All treatments were carried out during 6 weeks and oxidative parameters were evaluated in homogenized testicular tissue. The levels of vitamin E and the activity of glutathione peroxidase were lower (P < 0.05) in the testosterone group than in controls. However, vitamin C and malondialdehyde levels were higher (P < 0.05) in this group than in controls. The levels of reduced glutathione, beta-carotene, vitamin C and E increased, but malondialdehyde levels decreased in the vitamin E group, when compared with controls (P < 0.05). Vitamin E and beta-carotene levels were significantly higher (P < 0.05) in the combination group than in testosterone group. However, MDA levels were lower (P < 0.05) in combination group than in the testosterone group. In conclusion, administration of testosterone propionate led to a significant elevation of oxidative stress. Vitamin E is quite an effective antioxidant which protects rabbit testis against lipid peroxidation, and, testosterone-induced lipid peroxidation could be improved by additional vitamin E treatment.

Involvement of oxidative and nitrosative stress in promoting retinal vasculitis in patients with Eales' disease

OBJECTIVES

Eales' disease (ED) is an idiopathic retinal vasculitis condition, which affects retina of young adult males. The histopathological hallmark in ED is the adhesion of leukocytes to the endothelium and the infiltration of these cells into the retinal parenchyma. Phagocyte generated free radicals have been implicated in mediating tissue damage associated with various inflammatory vasculopathies. In the present study, we have investigated the possible role of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in causing retinal tissue damage in ED.

DESIGN AND METHODS

35 patients with ED and 20 healthy control subjects were included in the study. Monocytes (MC) were separated from peripheral blood of the respective study participants. Inducible nitric oxide synthase (iNOS) protein expression was assessed using Western blot and 3 nitrotyrosine (3NTYR) by reversed phase high performance liquid chromatography (RP HPLC). Thiobarbituric acid reactive substances (TBARS) were determined by measuring malondialdehyde (MDA) formed. Superoxide dismutase (SOD) activity was assayed based on the ability of SOD to inhibit auto-oxidation of epinephrine. Iron, copper and zinc content were determined using Atomic Absorption Spectrophotometer. Immunolocalization of iNOS and 3NTYR was performed on the surgically excised epiretinal membranes (ERM) from patients with ED.

RESULTS

There was a significant increase in the expression of iNOS, as well as 3NTYR accumulation, diminished SOD activity, elevated lipid peroxides, iron, copper and decreased zinc content in the MC of patients with ED when compared with healthy control subjects. The elevated levels of ROS and RNS products correlated with diminished antioxidant status in patients with ED. Strong immunoreactivity for iNOS and 3NTYR was observed in inflammatory cells and endothelial cells in ERM obtained from patients with ED.

CONCLUSIONS

Our findings from this study clearly reveal the involvement of RNS and ROS in the development of retinal vasculitis in ED. Based on our present study and earlier studies we confirm the role of free radicals in mediating retinal tissue damage in ED. Hence we believe selective inhibition of iNOS or supplementation with antioxidants vitamin E and C might be beneficial in controlling retinal vasculitis in patients with ED.