Lipid peroxidation and antioxidant status in stomach cancer.

BACKGROUND: Considerable evidences have linked oxidative damage and cancer. In this article, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) activities, and malondialdehyde (MDA) and nitric oxide metabolites' levels (NO(x)) were investigated in patients with stomach cancer. METHODS: All measurments were done by spectrophotometric techniques. RESULTS: We observed a significant decrease in the activities of SOD and CAT in tumour tissues when compared with control tissues. The different of GSHPx activities and NO metabolite' levels were not statistically significant. MDA levels were significantly increased. CONCLUSIONS: We conclude that increased MDA levels and decreased antioxidant enzyme activities can be valuable parameters in assessing the possible risk of cancer.

Serum cytokine changes in Turkish children infected with Giardia lamblia with and without allergy: Effect of metronidazole treatment.

The present report is a case control study aimed to determine the levels of cytokines and other parameters in the sera of allergy-complicated and uncomplicated giardiasic children before and after metronidazole treatment. The study included a total of 126 subjects; 52 giardiasic children, 34 allergy-complicated giardiasis (36.9%) and 34 healthy controls, as well as six cases of giardiasis simultaneously infected with other parasites or bacterial pathogens. Serum levels of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, soluble IL-2 receptor (sIL-2R), IL-6, IL-8, nitric oxide (NO), and C-reactive protein (CRP) were determined. TNF-alpha and sIL-2R levels significantly increased in giardiasic cases. IL-1beta, IL-6, IL-8, CRP, and NO levels increased only in the cases associated with allergy. All increased variables significantly decreased following metronidazole treatment and returned to normal levels. Metronidazole-treated patients became 100% parasite free. In conclusion, increased TNF-alpha and sIL-2R may be involved in pathogenesis of non-allergic giardiasis and probably Th1 type immune response seems to be predominant and this response may be protective rather than causative of the disease. Activation of the immune system takes place in giardiasis. It is broader and more intense in allergy-complicated giardiasis than that of uncomplicated cases, most probably due to non-invasive character of G. lamblia. Enhanced IgE production pointed to Th2-type immune response and confirms its association with allergy.

Role of IL-2, IL-4 and IL-10 in patients infected with Giardia lamblia.

A total of 116 sera collected from 86 persons infected with G. lamblia (40 males, 46 females) and 30 healthy controls (12 males, 18 females) were tested in order to determine the levels of some cytokines. Serum levels of IL-2, IL-4, and IL-10 were measured by the enzyme linked immunosorbent assay. The cytokine that increased most was IL-2 which had an elevated level of 46.5% and was followed by IL-4 (2.3%). IL-10 had not increased at all. The elevated ratio of IL-2 levels showed significant difference (p < 0.001). From these results, it can be concluded that Th1 immune response seems to be predominant in subjects infected with G. lamblia.

Th1 and Th2 inducing cytokines in Cystic echinococcosis.

This study included 62 subjects who presented at the Turgut Ozal Medical Centre in Malatya. Of these, 32 were infected with the larval stage of Echinococcus granulosus and the remaining 30 were healthy controls. The ratio of males to females was 0.45. Cystic echinococcosis (CE) occurred in all age groups; the youngest case was 12 years and the oldest case was 74 years old. The frequency of hydatid cysts located in liver was (78.1%) followed by lungs (15.7 %) and one in the brain. All patients recovered completely except for one woman (35 years old) in whom multiple cysts (21cysts) were detected in liver and omentum two years after the first operation. In 68.7 % of the cases, the cytokine that was most frequently increased was IL-4. The IL-2 cytokine increased to 46.8% followed by IL-10 (40.6 %). These results suggest that there are different immunoregulatory events and the cytokine response during CE may be in part related to the slight monocytosis observed in CE patients. In conclusion, concurrent Th1 and Th2 cytokine-type profiles were expressed in CE with the predominance of type Th2 cytokines.

Serum nitrite and nitrate levels in epileptic children using valproic acid or carbamazepine.

In experimental epilepsy studies, nitric oxide was found to act as both proconvulsant and anticonvulsant. The objective of this study was to investigate the effects of valproic acid and carbamazepine on serum levels of nitrite and nitrate, which are the metabolites of nitric oxide. To achieve this goal, serum nitrite and nitrate levels were determined in active epileptic 34 children using valproic acid and 23 children using carbamazepine and in non-active epileptic 38 children (control group) not using any antiepileptic drug. In the valproic acid group serum nitrite and nitrate levels were 2.66 +/- 2.11 micromol/l and 69.35 +/- 23.20 micromol/l, 1.89 +/- 1.01 micromol/l and 49.39 +/- 10.61 micromol/l in the carbamazepine group, and 1.22 +/- 0.55 micromol/l, 29.53 +/- 10.05 micromol in the control group, respectively. Nitrite and nitrate levels were significantly high in both valproic acid and carbamazepine groups compared to the control group (P < 0.01). When valproic acid and carbamazepine groups were compared to each other, level of nitrate was found statistically higher in the valproic acid group in relation to the carbamazepine group (P < 0.01), however, there was no statistically significant difference in the levels of nitrite (P > 0.05). No relation could be found between serum drug levels and nitrite and nitrate levels. According to these results, it can be suggested that valproic acid and carbamazepine might have antiepileptic effects through nitric oxide.

The role of nitric oxide and cytokines in asthma-like syndrome induced by sulfur dioxide exposure in agricultural environment.

BACKGROUND: We previously demonstrated that apricot sulfurization workers are exposed to high concentrations of SO(2), subsequently causing asthma-like syndrome. This study investigated the effects of SO(2) exposure on serum TNF-alpha, IL-1beta, IL-6, IL-8, nitrite and nitrate levels to understand the mechanism of SO(2)-induced bronchoconstriction in asthma-like syndrome. METHODS: We measured the serum levels of the cytokines, direct nitrite, total nitrite and nitrate obtained from 40 volunteer workers after an hour of exposure to SO(2) and 23 healthy controls. RESULTS: The concentrations of the cytokines, direct nitrite, total nitrite and nitrate were significantly (p<0.0001) higher in the workers than in the controls. The mean serum concentrations of TNF-alpha, IL-1beta, IL-6, IL-8, direct nitrite, total nitrite and nitrate were 430.60+/-397.03 pg/ml, 436.67+/-316.31 pg/ml, 752.11+/-394.95 pg/ml, 262.12+/-287.99 pg/ml, 7.75+/-3.34 micromol/l, 115.72+/-48.78 micromol/l and 107.97+/-46.19 micromol/l in the workers, while they were 9.83+/-3.12 pg/ml, <5 pg/ml, 7.49+/-1.27 pg/ml, 9.38+/-1.99 pg/ml, 2.17+/-0.77 micromol/l, 59.91+/-7.56 micromol/l and 57.74+/-7.20 micromol/l in the controls, respectively. CONCLUSION: These results show that TNF-alpha, IL-1beta, IL-6, IL-8 and nitric oxide may play a role in the pathogenesis of bronchoconstriction in asthma-like syndrome due to the SO(2) exposure.

The role of oxidative stress in bronchoconstriction due to occupational sulfur dioxide exposure.

BACKGROUND: We previously showed that apricot sulfurization workers (ASW) are exposed to high concentrations of SO(2), resulting in an asthma-like syndrome. The aim of this study was to evaluate whether oxidative stress plays a role in the pathogenesis of asthma-like syndrome due to the high concentrations of SO(2) exposure in agricultural environment. METHODS: Serum antioxidant enzyme activities and malondialdehyde (MDA) concentrations, which are markers of lipid peroxidation, and pulmonary function tests (PFT) were measured in 40 volunteer ASW and compared to 20 healthy control subjects. RESULTS: The superoxide dismutase (SOD, 2.2+/-0.6 vs. 3.2+/-0.7 U/ml), glutathione peroxidase (GSH-Px, 0.6+/-0.3 vs. 1.1+/-0.3 U/ml) and catalase (107.6+/-27.4 vs. 152.6+/-14.3 k/l) activities in ASW were significantly (p<0.0001) lower than controls, whereas the malondialdehyde concentration (4.1+/-0.9 vs. 1.9+/-5.3 nmol/l) was higher in ASW (p<0.0001). ASW had significant decreases in pulmonary function parameters after exposure. CONCLUSION: These results show that occupational exposure to high concentrations of SO(2) enhances oxidative stress and lipid peroxidation may be considered as a new mechanism of SO(2)-induced bronchoconstriction.

Urinary nitric oxide levels are increased and correlated with plasma concentrations in patients with Behçet's disease: is it a new urinary activity marker?

Nitric oxide (NO) is a free radical and serves many functions within the kidney. Excess NO causes glomerular injury. Behçet's disease (BD) is a systemic immunoinflammatory vasculitis, affecting every organ in the body including the kidneys (subclinic glomerulonephritis). We investigated the role of urinary total nitrite levels (end product of NO) in BD and evaluated whether urinary concentrations were correlated with its plasma levels or disease activity. Thirty-six consecutive Behçet's patients (19 men, 17 women; 35.9 years), and 20 age- and sex-matched healthy control volunteers (12 men, eight women; 33.2 years) were divided into an active (n = 16) and inactive (n = 20) period. Urinary and serum NO levels ( micromol/mg urinary creatinine) were higher in BD patients (4.1 +/- 0.3) than control subjects (1.7 +/- 0.2; P < 0.001). Serum NO levels in Behçet's patients and control subjects were 51.3 +/- 9.8 and 21.7 +/- 7.3 micromol/L, respectively (P < 0.001). Active patients had higher urinary NO excretion (4.9 +/- 0.3) than inactive patients (3.3 +/- 0.3; P < 0.01). Urinary NO levels were correlated with its serum levels (r2 = 0.69, P < 0.001). Higher urinary NO levels found in BD may be produced by the kidney as a result of an inflammatory stimulation. As excess NO is toxic to the tissues, increased NO levels may play a role in mediating subclinic glomerular injury of such patients. However, we could not determine the exact site(s) of NO synthesis by the kidney, such as the glomeruli, blood vessels and/or the tubular cells. Whatever the source, urinary NO levels may be used as a new activity marker in the diagnosis and follow up of BD by serial measurements.

Effects of long-term solvent exposure on blood cytokine levels and antioxidant enzyme activities in house painters.

The aim of this study was to examine solvent-associated effects on blood cytokine levels, antioxidant enzyme activities, and malondialdehyde (MDA) concentration in house painters. Trace element (Cu and Zn) and nitrite and nitrate levels as well as protein concentrations in erythrocytes and serum were determined. Thirty male house painters and 30 male clerical workers were included in the study. There were 13 smokers and 17 nonsmokers in each group. Hemoglobin concentrations were significantly lower in house-painter blood compared to controls. House painters had significantly higher concentrations of erythrocyte protein (excluding hemoglobin), whereas no significant difference was observed between serum protein levels. Proinflammatory cytokine levels, such as tumor necrosis factor-alpha and interleukin-8, were significantly increased in house painters' sera. Interleukin-6 was below the detection limit of the assay in both groups. Interleukin-1beta and cytokine receptor interleukin 2R concentrations were not significantly affected. Furthermore, a three- to fourfold increase in nitrite and nitrate concentrations was found in house painters' sera. Serum superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities were significantly lower in house painters compared to controls. Malondialdehyde (MDA) concentration, a measure of lipid peroxidation, was found to be significantly elevated. In house painters, erythrocyte carbonic anhydrase and catalase activities were elevated approximately 11- fold and 2-fold, respectively. Zinc levels were significantly decreased in house painters' sera. Smoking was not found to be a major confounder for the association between solvent exposure and blood parameters.