Oxidative stress enhances the immune response to oxidatively modified catalase enzyme in patients with Graves' disease.

BACKGROUND: Oxidative stress is associated with several autoimmune disorders and oxidative modification of proteins that may result in autoimmune response. This study aims to evaluate the catalase (CAT) activity and the autoimmune response against the native CAT and the oxidatively modified enzyme in patients with Graves' disease (GD) and healthy controls in a comparative way. METHODS: The CAT activity was evaluated via spectrophotometric method. Using enzyme-linked immunosorbent assay, the reactivities of autoantibody toward native, malondialdehyde (MDA) and hydrogen peroxide (H2 O2 ) modified CAT were evaluated in plasmas of patients and controls. RESULTS: Reduced CAT activity was found in patients compared with controls (P < .05). It was proved that levels of IgG antibodies against MDA-modified CAT were higher than against unmodified ones (P < .001). No changes were found for the reactivities to H2 O2 -modified CAT. Positive correlation was found between the reactivity to MDA-modified CAT and the triiodothyronine level (P < .001, r = .6). CONCLUSION: Our findings incriminate the MDA in the autoantibodies reactivity to oxidatively modified CAT leading to a disturbed oxidative profile and/or the progression of GD pathology.

Lawsonia inermis essential oil: extraction optimization by RSM, antioxidant activity, lipid peroxydation and antiproliferative effects.

BACKGROUND: The present study was focused on the optimization of yield of the essential oil extraction from leaves of Lawsonia inermis, and the determination of chemical composition, antioxidant activities, and lipid peroxydation and antiproliferative effects. METHODS: Henna essential oil (HeEO) were extracted by hydrodistillation; the identification of the chemical composition were done by GC/MS method. HeEO was analyzed for antioxidant power in: (1) chemical system by the DPPH test, the ABTS test and the total antioxidant activity test; and (2) in biological system by lipid peroxydation tests (MDA and DC) in cells culture. The cytotoxicity effects of HeEO were assessed using MTT assay against Raji and HeLa cell lines. RESULTS: The optimal extraction yield was 6.8 g/100 g d.b. HeEO showed a remarkable anti-oxidant activities including DDPH (42%), ABTS (87%) and the power of ammonium phosphomolybdate (2992 ± 230 mg of HeEO by equivalent to 1 mg of vitamin C in terms of total antioxidant power). CONCLUSION: Beyond notable antioxidant activities of the HeEo, our results showed a significant decrease in the production of ERO in the Raji cell line. The anti-tumor power of the Henna essential oil shows an interesting cytotoxicity effect (IC50 at 0.26 µg/mL for Raji and at 1.43 µg/mL for HeLa) with a total mortality percentage reaching 60%, for both.

In vitro biological properties and health benefits of a novel sulfated polysaccharide isolated from Cymodocea nodosa.

BACKGROUND: During the last few decades, there has been a growing interest in the search for novel bioactive compounds from marine origins. METHODS: The present study is the first to determine the molecular characterization which it was deposited in the genebank database, to investigate and evaluate the biological properties of sulfated polysaccharide from Cymodocea nodosa (CNSP) seagrass. RESULTS: The results revealed that CNSP had high activity in total antioxidant assay (59.03 mg ascorbic acid equivalents/g extract), reducing power (OD = 0.3), DPPH radical scavenging (IC50 = 1.22 mg/ml) and ABTS radical scavenging (IC50 = 1.14 mg/ml). It was also noted to exhibit antimicrobial activity against a wide range of microorganisms, with important inhibition zones. The results revealed that CNSP was able to inhibit the proliferation of Hela cell lines with a dose-dependent manner. CONCLUSION: Overall, the results presented in this study demonstrate that CNSP has several attractive antioxidant, antimicrobial and antiproliferative properties with potential benefits towards health.

Human sperm Toll-like receptor 4 (TLR4) mediates acrosome reaction, oxidative stress markers, and sperm parameters in response to bacterial lipopolysaccharide in infertile men.

PURPOSE: To study the role of Toll-like receptor 4 (TLR4) in human spermatozoa and to assess sperm parameters, oxidative stress markers, and acrosome reaction in response to the stimulation of TLR4 by its ligand, the lipopolysaccharide (LPS), as a major endotoxin of Gram-negative bacteria. METHODS: Our study was carried out in 73 sperm samples from patients undergoing semen analysis for couple infertility investigations. The studied patients were divided into three groups: normozoospermic fertile patients (n = 13), patients with abnormal and leukospermic semen (n = 13), and patients with abnormal and non-leukospermic semen (n = 47). TLR4 expression in human spermatozoa was initially analyzed by western blot. Sperm samples were incubated in the presence of LPS (200 ng/ml) for 18 h. Then, sperm motility and vitality were evaluated by microscopic observation and oxidative stress markers as malondialdehyde (MDA) and carbonyl groups (CG) were spectrophotometrically assessed in neat and selected sperm. A triple-stain technique was also performed to evaluate acrosome reaction in 15 sperm samples from infertile patients. RESULTS: TLR4 expression was confirmed in human spermatozoa with a molecular weight of 69 kDa. In the normozoospermic group, no significant differences in sperm parameters and oxidative stress markers were shown after incubation with LPS in neat and selected sperms. Regarding samples from the non-leukospermic group, LPS reduced spermatozoa motility and vitality rates in selected sperm (P = 0.003; P = 0.004, respectively). A significant increase of MDA and CG levels was also detected (P = 0.01; P = 0.02, respectively). However, only the MDA levels were significantly increased (P = 0.01) in neat LPS-stimulated sperm. The same results were shown within the leukospermic group. The comparison between the two groups, leukospermic and non-leukospermic, in selected sperms showed a more important LPS effect in the leukospermic group significantly on motility and MDA rates (P = 0.006; P = 0.009, respectively). Furthermore, a significant decrease in reacted spermatozoa rate was detected in response to LPS in selected sperm samples from infertile men (P = 0.03). CONCLUSIONS: These findings indicate that human spermatozoa express TLR4 and respond to LPS stimulation with alterations in viability, motility, and the acrosome reaction implicating reactive oxygen species (ROS) production in sperm samples from infertile patients.

Methyl-thiophanate increases reactive oxygen species production and induces genotoxicity in rat peripheral blood.

Methylthiophanate is one of the widely used fungicides to control important fungal diseases of crops. The aim of this study was to elucidate the short-term hematoxicity and genotoxicity effects of methylthiophanate administered by intraperitoneal way at three doses (300, 500 and 700 mg/kg of body weight) after 24, 48 and 72 h. Our results showed, 24 h after methylthiophanate injection, a hematological perturbation such as red blood cells (p < 0.05, p < 0.05 and p < 0.01) and hemoglobin content (p < 0.05), respectively, and a noticeable genotoxic effect in WBC evidenced by a significant increase in the frequency of the micronuclei and a decrease in cell viability. An increase in erythrocyte osmotic fragility was also noted after 24 and 48 h of methylthiophanate treatment at graded doses. A significant increase in hydrogen peroxide, advanced oxidation of protein products and malondialdehyde levels, in erythrocytes of methylthiophanate-treated rats with 300, 500 and 700 mg/kg of body weight, was also observed after 24 h of treatment (p < 0.05, p < 0.01 and p < 0.001, respectively), suggesting the implication of oxidative stress in its toxicity. Antioxidants activities of superoxide dismutase and glutathione peroxidase in erythrocytes significantly increased (p < 0.001) 24 h after the highest dose injected. While all these parameters were improved after 72 h of methylthiophanate injection (300, 500 and 700 mg/kg body weight). In conclusion, these data showed that the exposure of adult rats to methylthiophanate resulted in oxidative stress leading to hematotoxicity and the impairment of defence system, confirming the pro-oxidant and genotoxic effects of this fungicide.

In vitro Effects of Olive Leaf Extract (Oleuropein) on Human Sperm Parameters and Oxidative Stress Induced by Bacterial Lipopolysaccharide (LPS).

Recently, biomolecules from natural products have paved the way for novel drug in the treatment of some diseases in vitro and in vivo models as diabetes, cancer and infertility. As such, we aimed to evaluate the capacity of Oleuropein (OLE), the major bio-phenol in olive leaf, to protect human sperm against bacterial lipopolysaccharide (LPS) inducing sperm oxidative stress and defective sperm functions. The toxic effect of OLE on human sperm was firstly investigated by evaluating sperm parameters after incubation during 60 minutes with different concentrations. Determined non-toxic concentration was then used to evaluate the capacity of OLE to protect sperm against LPS oxidative damages and sperm parameters alterations. Thus, sperms were consecutively incubated with LPS (10 µg/mL) and OLE (40 µg/mL) during 60 minutes, then submitted to sperm parameters analysis and oxidative stress assessment by measuring malondialdehyde (MDA), carbonyl groups (CG) levels and the activity of some antioxidant enzymes: superoxide dismutase (SOD) and catalase (CAT). A significant decrease of sperm parameters as well as a significant increase in MDA levels, CG levels, SOD and CAT activities was found after stimulation by LPS. However, a non-significant difference was shown comparing sperms treated by LPS and OLE with LPS-treated control sperms. Consequently, despite the high antioxidant and anti-inflammatory capacity of OLE reported in diverse cells, this phenolic compound seems to be not appropriate to protect human sperm in vitro against induced LPS oxidative stress and seems to have a "double-edged sword" behavior.

A new Lactobacillus plantarum strain, TN8, from the gastro intestinal tract of poultry induces high cytokine production.

This study aimed to determine the probiotic potential of 100 strains of Lactic Acid Bacteria (LAB) isolated from different intestinal segments of indigenous poultry in Tunisia. The strains were submitted to a battery of standard tests and criteria commonly used for determining their probiotic properties and attributes. The findings revealed that 19 of the isolates exhibited antimicrobial activity against 4 pathogenic bacteria, and that 4 (TN1, TN8, TN7, and TN13) showed good resistance to pH 3 and 5% bovine bile. Three isolates, namely TN1, TN8, and TN13, showed sensitivity to several antibiotics and were, therefore, selected for further enzymatic activity assays. Two isolates, namely TN1 and TN8, showed high efficacy of adhesion to chicken enterocytes. The cytokines released after stimulation by the two isolates showed high anti-inflammatory profiles, with an increased rate of Interleukin-10 (IL-10) production for the TN8 strain. Showing the highest performance, TN8 was submitted to 16S rRNA gene sequencing, which revealed that the strain was of the species Lactobacillus plantarum. Overall, the findings indicate that the Lactobacilli from poultry intestine has a number of promising properties that make it candidate for application as a probiotic additive in poultry industry.

Induction of Epstein-Barr virus (EBV) lytic cycle in vitro causes lipid peroxidation, protein oxidation and DNA damage in lymphoblastoid B cell lines.

BACKGROUND: We investigated the oxidative modifications of lipids, proteins and DNA, potential molecular targets of oxidative stress, in two lymphoblastoid cell lines: B95-8 and Raji, after EBV lytic cycle induction. Conjugated dienes level was measured as biomarker of lipid peroxidation. Malondialdehyde adduct and protein carbonyl levels, as well as protein thiol levels were measured as biomarkers of protein oxidation. DNA fragmentation was evaluated as biomarker of DNA oxidation. RESULTS: After 48 h (peak of lytic cycle), a significant increase in conjugated dienes level was observed in B95-8 and Raji cell lines (p = 0.0001 and p = 0.019 respectively). Malondialdehyde adduct, protein carbonyl levels were increased in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls (MDA-adduct: p = 0.008 and p = 0.006 respectively; Carbonyl: p = 0.003 and p = 0.0039 respectively). Proteins thiol levels were decreased by induction in B95-8 and Raji cell lines (p = 0.046; p = 0.002 respectively). DNA fragmentation was also detected in B95-8 and Raji cell lines after EBV lytic cycle induction as compared to controls. CONCLUSION: The results of this study demonstrate the presence of increased combined oxidative modifications in lipids, proteins in B95-8 and Raji cells lines after EBV lytic cycle induction. These results suggest that lipid peroxidation, protein oxidation and DNA fragmentation are generally induced during EBV lytic cycle induction and probably contribute to the cytopathic effect of EBV.

Protective effect of quercetin against oxidative stress caused by dimethoate in human peripheral blood lymphocytes.

BACKGROUND: The aim of this study is to investigate the effect of quercetin in alleviating the cytotoxic effects of Dimethoate in human peripheral blood lymphocytes. METHODS: Lymphocytes were divided into too groups. The first group, lymphocytes were incubated for 4 h at 37°C with different concentrations (0, 40, 60 and 100 mM) of Dimethoate. The second group was preincubated with quercetin for 30 min and followed by Dim incubation for 4 h at 37°C. RESULTS: Following in vitro incubation, Dimethoate caused a significant increase in malondialdehyde levels, a significant decrease in thiol levels, as well as a significant increase in superoxide dismutase, and catalase activities in lymphocytes at different concentrations. Quercetin pretreated lymphocytes showed a significant protection against the cytotoxic effects inducted by Dimethoate on the studied parameters. CONCLUSION: In conclusion, antioxidant quercetin could protect against Dimethoate-induced oxidative stress by decreasing lipid peroxidation, protein oxidation and increasing superoxide dismutase and catalase activities in human lymphocytes.

Antioxidant activity of ethanolic extract of inflorescence of Ormenis Africana in vitro and in cell cultures.

BACKGROUND: The antioxidant potency of the hydroethanolic extract of Ormenis Africana (HEOA), Asteraceae was evaluated with regards to total polyphenol, flavonoid and anthocyanins content. Antioxidant activity has been assessed chemically and biologically. First, the free radical scavenging ability of HEOA was evaluated using two commonly in vitro tests: ABTS and DPPH radicals. Then, the protection effect of this extract against oxidative stress was conducted in HeLa cells treated with Fe2+ or H2O2. Oxidative stress was evaluated by measuring the lipid peroxidation levels (TBARs and DC) and the antioxidant enzymes activities (catalase and Superoxide dismutase). Cytotoxic effect of HEOA was prealably determined against HeLa cell line by MTT assay. RESULTS: HEOA contain considerable levels of antioxidant compound as evidenced by high amount of polyphenols (312.07 mg GAE/g dray matter), flavonoids (73.72 ± 1.98 mg QE/g dray matterl) and anthocyanins (0.28 ± 0.09 mg Cy-3-glu E/g dray matter). DPPH and ABTS assays showed a high antioxidant activity (IC50 = 24 µg/ml; TEAC = 2.137 mM) which was comparable to BHT.In biological system, HEOA exhibited a 50% cytotoxic concentration evaluated as 16.52 µg/ml. Incubation of HeLa cell line with no cytotoxic concentrations resulted in a remarkable protection from oxidative stress induced by Fe2+ or H2O2 which was evidenced by a decrease of MDA and CD levels as well as a diminution of antioxidant enzymes activities (Catalase and SOD) as compared to cells treated with Fe2+ or H2O2 alone. CONCLUSION: The hydroethanolic extract of O. Africana could thus be considered as a source of potential antioxidants. The results of this study will promote the reasonable usage of this plant in food and pharmacy industries as well as in alternative medicine and natural therapy.

Dimethoate-induced oxidative stress in human erythrocytes and the protective effect of vitamins C and E in vitro.

Organophosphorus insecticides may induce oxidative stress leading to the generation of free radicals and alteration in the antioxidant system. The aim of this study was to examine the potency of Dimethoate (Dim) to induce oxidative stress response in human erythrocyte in vitro and the role of Vitamins C (Vit C) and E (Vit E) in alleviating the cytotoxic effects. Erythrocytes were divided into three groups. The first group, erythrocytes were incubated for 4 h at 37 °C with different concentrations (0, 20, 40, 60, 80, and 100 mM) of Dim. The second and third groups were preincubated with Vit C or Vit E, respectively, for 30 min and followed by Dim incubation for 4 h at 37 °C. Following in vitro exposure, Dim caused a significant increase in malondialdehyde (MDA) levels, superoxide dismutase (SOD), and catalase (CAT) in erythrocytes at different concentrations. Vit E or Vit C pretreated erythrocytes showed a significant protection against the cytotoxic effects inducted by Dim on the studied parameters. In conclusion, antioxidant Vit E and C could protect against Dim-induced oxidative stress by decreasing lipid peroxidation and hyperactivity of SOD and CAT in human erythrocytes.

Effect of extraction procedures on the chemical structure, antitumor and anticoagulant properties of ulvan from Ulva lactuca of Tunisia coast.

The effect of extraction procedures on chemical composition, structural, antitumor and anticoagulant properties of the sulphated polysaccharide 'ulvan' from the green seaweed Ulva lactuca were investigated. The structural features of ulvans were carried out by FTIR and by one- and two- dimensional 1H and 13C NMR spectroscopic. The ulvans were mainly composed of rhamnose, xylose, and uronic acid. Chemical and spectroscopic analyses demonstrated that ulvans were constituted of (1→4)-ß-glucuronic acid, (1→3,4)-α-L-rhamnose-3-sulphate and (1→4)-α-xylose. The extraction procedures effect were observed in chemical structure, Mw and biological activities. Cytotoxic activity of enzymatic-chemical extract on cervical cancer cells (HeLa) (IC50 = 1000 µg/mL) was higher than on normal peripheral blood lymphocytes cells (PBL). Acid extracts promoted to reduce HeLa cells and to grow PBL cells. At high concentrations, acid extracts showed the highest APTT and TT clotting time. Antitumoral and anticoagulant activities of ulvans from Ulva lactuca promote their use as effective therapeutic agent.

Induction of Epstein-Barr virus (EBV) lytic cycle in vitro causes oxidative stress in lymphoblastoid B cell lines.

Here, we investigated the effect of induction of the Epstein-Barr virus (EBV) viral lytic cycle on the oxidant/antioxidant balance in three lymphoblastoid cell lines: B95-8, Raji, and LCL C1. The induction of the EBV lytic cycle was done by a non-stressing dose of 12-0-tetradecanoylphorbol-13-acetate (8 nM). Oxidative stress was assessed by measuring malondialdehyde as a parameter of lipid peroxidation, the levels of glutathione, and the activities of three antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase). After 48 h (peak of lytic cycle), a significant decrease in superoxide dismutase activity was observed in B95-8, Raji, and LCL C1 cells (P < 0.05). In addition, in B95-8 cells also a significant decrease of catalase activity was detected (P < 0.05). The glutathione peroxidase activity and the glutathione level were not significantly modified by the induction in any of the cell lines. We found a significant rise in malondialdehyde levels in B95-8, Raji, and LCL C1 cells after the induction of the lytic cycle compared to controls (P < 0.05). In conclusion, induction of EBV lytic cycle in lymphoblastoid cells causes increased oxidative stress in the host cells within 48 h, a process that could be involved in malignant transformations.

High levels of autoantibodies against catalase and superoxide dismutase in nasopharyngeal carcinoma.

INTRODUCTION: Autoantibodies against the antioxidant enzymes have been described in Epstein-Barr virus-associated diseases. Here, we hypothesize that Epstein-Barr virus (EBV), which is associated with nasopharyngeal carcinoma (NPC), induces anticatalase and/or antisuperoxide dismutase autoantibodies that inhibit catalase and/or superoxide dismutase activities and thereby contribute to the oxidative stress status described in this pathology. METHODS: Using a standard enzyme-linked immunosorbent assay (ELISA), the levels of immunoglobulin G (IgG), and M (IgM) directed against catalase and superoxide dismutase in the sera of 30 NPC patients and 30 healthy control individuals were evaluated. The antioxidative profile was tested among the same patients by measuring serum catalase and superoxide dismutase activities. To investigate the implication of EBV in the establishment of autoantibody production in NPC patients, a correlation study between serological testing for EBV viral capsid antigen immunoglobulin G (VCA IgG) and autoantibodies against both enzymes was undertaken. FINDINGS: The levels of IgG against superoxide dismutase and catalase were found to be increased in sera patients compared to controls (P<0.001). NPC patients exhibited decreased catalase (P<0.001) and superoxide dismutase activities (P<0.001) in their sera. However, a positive correlation between superoxide dismutase IgM antibody and IgG antibody titers to VCA (P<0.05, r=0.483, n=21) was found. A positive correlation between catalase (IgM) antibodies and IgG antibody titers to VCA (P<0.05, r=0.546, n=30) was also found. CONCLUSION: High levels of anticatalase and antisuperoxide dismutase antibodies in the sera of NPC patients were found.

Imipenem toxicity in male reproductive organs as a result of inflammatory microenvironment and oxidative stress in germinal cells.

Imipenem is a beta-Lactam antibiotic characterized by a broad spectrum of activity. It is prescribed to treat severe infections. Our goal is to investigate toxicity induced in male rat reproductive systems following exposure to this drug (15, 50 or 100 mg/kg) compared to gentamicin (50 mg/kg) treatment. Effects of imipenem on reproductive organ weights, histoarchitecture, sperm parameters, and oxidative stress parameters were evaluated. Serum testosterone levels were measured. Apoptosis and inflammatory behaviors were investigated by immunohistochemical proteins expression analysis of apoptosis regulator BAX (Bax), B-cell lymphoma 2 (Bcl-2), and interleukin-1 beta (IL-1 beta) in testis. Results showed a significant decrease in male fertility parameters including sperm count, sperm motility, reproductive organ weights and serum testosterone levels after imipenem administration as compared to the control and gentamicin treated groups. Increased sperm abnormality was significant in animals treated with high doses of imipenem. Oxidative stress analysis revealed an expressed increase in lipid peroxidation and carbonyl groups levels in testicular tissues compared to control. Similar results were observed with superoxide dismutase and catalase activities from testicular tissues. In addition, severe testicular lesions were observed in the seminiferous tubules as well as important impairments in spermatogenesis testifying an inflammatory microenvironment confirmed by the intensive expression of IL1-beta and Bax protein by germinal cells and Bcl-2 by Leydig cells. In conclusion, imipenem treatment with high doses was found to lead to oxidative stress in male reproductive organs and an inflammatory microenvironment leading to spermatogenesis dysfunction and histopathological changes in the testis.

Optimization of Cinnamon (Cinnamomum zeylanicum Blume) Essential Oil Extraction: Evaluation of Antioxidant and Antiproliferative Effects.

Having high cytotoxicity cell line effect, Cinnamomum zeylanicum Blume essential oil offers a novel approach to the chemotherapy treatment. In order to enhance its quantity/purity, the experimental conditions to produce essential oil should be more exploited. Steam distillation was used to isolate essential oil, and its conditions' optimization was carried out with the surface-response methodology. The maximum amount (2.6 g/100 g d.b.) was obtained under minimum condensation water flow (0.8 mL/min), a sample size of 6.5 cm, a saline solution concentration of 262.5 g/L, and five washings. The produced essential oil contains >77% of polyphenols. In vitro cytotoxicity was examined using an MTT assay against HeLa and Raji cell lines. The essential oil's capability to inhibit the proliferation of HeLa and Raji cell lines was studied under some conditions presenting IC50 values of 0.13 and 0.57 µg/mL, respectively. The essential oil was evaluated for its potential as an antioxidant by using in vitro models, such as phosphomolybdenum, DPPH, and H2O2 methods, in comparison with the synthetic antioxidant BHT (butylated hydroxytoluene) and ascorbic acid (vitamin C) as positive controls. The ammonium phosphomolybdate potency in the present study is of the order of 108.75 ± 32.63 mg of essential oil/equivalent to 1 mg of vitamin C in terms of antioxidant power, and the antioxidant activity of DPPH-H2O2 was 21.3% and 55.2%, respectively. The Cinnamomum zeylanicum Blume essential oil (CEO) covers important antioxidant and antiproliferative effects. This can be attributed to the presence of few minor and major phenolic compounds.

Synthesis and recovery of high bioactive phenolics from table-olive brine process wastewater.

The generated wastewater of table-olive brine processing contains a high amount of polyphenols which are endowed with interesting biological activities. The ethyl acetate extract (EAE) of such wastewater shows high hydroxytyrosol (HT) and tyrosol concentrations of 690 and 98 mg g(-1) dry weight extract, respectively. Phenolic compounds analysis was performed by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was evaluated by the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-Azinobis[3-ethylbenzothiazoline-6-sulfonate] radicals. Total polyphenol content was estimated with the Folin-Ciocalteu assay. Hydroxytyrosol has DPPH and ABTS radicals scavenging activities higher than 2,6-di-tert-butyl-hydroxytoluene (BHT), while triacetylated hydroxytyrosol (triAcHT) was devoid of any antioxidant activity. The assessment of these antioxidant compounds in biological systems was carried out by the determination of their in vitro cytotoxicity against two different human cancer cell lines (HeLa and DG75) and normal peripheral blood lymphocytes (PBL) using the MTT assay. The 50% cytotoxic concentrations were ranged between 27 and 210 microg mL(-1) for Hela and DG75. At the same concentration range, the EAE and the pure HT and triAcHT exhibited an insignificant cytotoxicity against PBL. Incubation of HeLa and DG75 cells with non-cytotoxic concentrations of EAE, HT or triAcHT resulted in a remarkable protection from the oxidative stress induced by Fe(2+). The antimicrobial activity evaluated by the broth dilution NCCL method using Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica) bacteria and (Candida albicans, Aspergillus niger) fungi showed a broad spectrum bactericidal and fungicidal effect of table-olives-EAE, HT and triAcHT. The MICs vary from 125 to 500 microg mL(-1) for bacteria and from 500 to 2000 microg mL(-1) for fungi.

Differential reactive oxygen species production of neutrophils and their oxidative damage in patients with active and inactive systemic lupus erythematosus.

OBJECTIVE: Increasing interest is given to the involvement of the innate immunity and especially Polymorphonuclear neutrophils (PMN) in the physiopathological process of inflammatory diseases such as systemic lupus erythematosus (SLE). Here, we investigated the oxidative burst and damages in SLE patients neutrophils, considering the two phases of the disease, the active and the remission/inactive states. METHODS: This study was conducted on 30 SLE patients and 23 healthy controls. The oxidative burst in neutrophils of SLE patients and controls was triggered by fMLP and TPA, while reactive oxygen species (ROS) production was evaluated using a chemiluminescence assay. Oxidative damages in neutrophils were assessed by measuring Free thiol groups level and carbonyl groups, as protein oxidative markers. The malondialdehyde (MDA) level informed about the lipid peroxidation (LPO) and the catalase activity indicated the antioxidant enzymatic activity. RESULT: Compared to controls, SLE patients exhibited a significantly increased level of ROS production concomitantly to a decreased response time. Their Neutrophils were characterized by a decreased level of MDA and high levels of protein oxidation as evidenced by increased carbonyl groups and decreased SH levels. The catalase activity was higher in SLE patients' neutrophils compared to controls. When patients were clustered according to the disease activity, PMN of patients in active phase showed, paradoxically, a lower ROS production and exhibited higher oxidative damages than the inactive group. CONCLUSION: Our results highlight an altered behavior of LES patients derived PMN particularly in the active phase of the disease. The evaluation of the redox status including the rate of ROS production could be a biological marker to follow the activity of the disease.

Proteins oxidation and autoantibodies' reactivity against hydrogen peroxide and malondialdehyde -oxidized thyroid antigens in patients' plasmas with Graves' disease and Hashimoto Thyroiditis.

The aim of this study was to evaluate proteins oxidation in plasmas of two autoimmune thyroid diseases (AITD): Graves' disease (GD) and Hashimoto Thyroiditis (HT), and to determine whether oxidative modification of thyroid antigens (T.Ag) enhanced the reactivity of autoantibodies in plasmas of AITD patients compared with the reactivity towards native T.Ag. Carbonyl and thiol groups and MDA-protein adducts were assessed spectrophotometric methods in plasmas of 74 AITD patients and 65 healthy controls. The reactivities immunoglobulin (Ig)G autoantibodies towards malondialdéhyde (MDA)-modified T.Ag, hydrogen peroxide (H2O2)-modified T.Ag, native T.Ag and native derm were checked by enzyme-linked immunosorbent assay (ELISA). Evaluation of oxidized proteins exhibited high levels of MDA bound to proteins and carbonyl groups, as well as reduced thiol level in plasmas of AITD patients by comparison to healthy controls (p < 0.05). The ELISA test showed that AITD patients' plasmas' reactivity to native T.Ag was significantly increased to the reactivity towards native derm, whereas, no differences were found in the reactivity to native T.Ag and derm in controls plasmas. In addition, treatment of T.Ag by oxidants revealed enhanced reactivity of IgG circulating autoantibodies against H2O2-oxidized T.Ag compared to native ones (p < 0.001) in plasmas of both AITD. Also, reactivity's to MDA-oxidized T.Ag in GD plasmas decreased compared to native ones (p < 0.05) and no changes were noted for HT. Pearson correlation study resulted in positive correlation between reactivity's to H2O2-oxidized T.Ag and free triodotyronine level in GD patients (r = 0.42, p < 0.05) in one hand and thyroid stimulating hormone level in HT patients in the other (r = 0.65, p < 0.001). The data suggest that high production of H2O2 probably occurred during hormone synthesis could contribute to protein oxidation in AITD and to create neoepitopes responsible for autoantibody reactivity's to H2O2-oxidized T.Ag enhancement. These results provide support to the involvement of oxidative stress in AITD development and/or exacerbation.

A comparative study of nuclear 8-hydroxyguanosine expression in Autoimmune Thyroid Diseases and Papillary Thyroid Carcinoma and its relationship with p53, Bcl-2 and Ki-67 cancer related proteins.

PURPOSE: To investigate whether the oxidative stress is involved in the evolution of Graves' disease (GD) and Hashimoto thyroiditis (HT) into Papillary Thyroid Carcinoma (PTC), 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cancer related proteins (Bcl-2, p53 and Ki-67) expressions were evaluated in these pathologies. PATIENTS AND METHODS: Immunohistochemical method was applied on 25 thyroid tissues. Allred score (AS) serving to evaluate the immunostaining is based on a scale from 0 to 8. "Negligible expression" was assigned to a score of 0 to 2, "expression" and "overexpression" were attributed to a score of 3-5 and ≥6 respectively. RESULTS: PTC cancer cells exhibited 100% 8-OHdG "overexpression" compared to 87.5% in PTC non-malignant epithelial (NME) ones (p<0.05). Higher 8-OHdG AS was found in PTC NME cells compared to GD and HT (p<0.001, p<0.05 respectively). "Overexpression" of Bcl-2 was noted in all PTC cell types. Remarkably, just like the PTC cancer and NME cells 33.3% of HT and 50% of GD patients' revealed simultaneous "overexpression" of Bcl-2 and 8-OHdG in epithelial cells. No staining was detected for p53 in all pathologies. PTC lymphoid cells exhibited 100% "overexpression" for 8-OHdG and Bcl-2 with concomitant "negligible expression" for Ki-67 in 87.5% of patients. In contrast, HT lymphoid cells showed 22.2% "expression" and GD 62.5% "expression" and 12.5% "overexpression" of Ki-67. CONCLUSIONS: Simultaneous "overexpression" of 8-OHdG and Bcl-2 in GD and HT could be considered as prognostic markers while "negligible expression" of Ki-67 in PTC lymphoid cells suggests an anergic state favoring the tumor escapes from the immune system.