CD4+CD25+ Treg cells in patients with toenail onychomycosis.

The essential role played by CD25+CD4+ regulatory T (Treg) cells in the control of immunity against some pathogens such as Helicobacter pylori is now well established. But their role in cutaneous fungal infections is still unknown. Onychomycosis is the chronic fungal infection of the nails, which is very common. The aim of this study was to evaluate possible relationship of CD4+CD25+ Treg cells and onychomycosis. Peripheral blood samples were investigated for CD4+CD25+ Treg cells using flow cytometry analysis in 43 toenail onychomycosis patients and in 30 healthy controls. We have found that onychomycosis patients had a higher expression of CD25+CD4+ Treg cells than controls, with values of 8.45 +/- 4.47% versus 4.64 +/- 1.59%, respectively (P = 0.001). The results of this study suggests that increased numbers of CD4+CD25+ Treg cells may play a role in failure of clearance of dermatophytes from skin by preventing the protective inflammation which is leading to development of onychomycosis. Accordingly, we address the possibility that CD4+CD25+ Treg cells may play a role in immune pathogenesis of other superficial fungal infections.

In vivo effects of meloxicam, celecoxib, and ibuprofen on free radical metabolism in human erythrocytes.

One of the major groups of chemical mediators involved in the inflammatory response is the prostaglandins, which are synthesized from arachidonic acid by the enzyme cyclooxygenase. The aim of this study is to compare the in vivo effects of celecoxib, meloxicam, and ibuprofen on the activities of catalase (CAT), glutathione peroxidase (GSHPx), superoxide dismutase (SOD) as well as malondialdehyde (MDA), and antioxidant potential levels (AOP) in human erythrocytes. Patients diagnosed as osteoarthritis were included in the study. Patients were treated with Celecoxib (200 mg/d) (n = 12), Meloxicam (15 mg/d) (n = 12), and Ibuprufen (1200 mg/d) (n = 9) for 21 days. SOD, CAT, GSHPx activities, MDA, and AOP levels were investigated in human erythrocyte haemolysates. SOD activity and AOP levels were significantly decreased in all NSAID groups when we compared the values before and after 21 days of celecoxib, meloxicam, ibuprofen treatment. There were no significant difference in CAT, GSHPx activities, and MDA levels before and after treatment in each group. Decreased SOD activities are thought to be related with the increased superoxide anion. Decreased AOP levels may indicate impairment in the total antioxidant defence system. These NSAIDs have similar effects on free radical metabolism on human erythrocytes; despite some difference in action mechanisms.

Effects of cigarette smoking with different tar content on erythrocyte oxidant/antioxidant status.

In this study, the effects of cigarettes with differing tar content on erythrocyte oxidant/antioxidant status was investigated. Malondialdehyde (MDA) as an indicator of oxidant status and superoxide radical scavenger activity (SSA) as an indicator of antioxidant status were measured in erythrocytes from 20 smokers and 10 non-smoker controls. Ten of the 20 smoking subjects smoked five cigarettes with full flavour low tar (FFLT with 12 mg tar) and the others smoked five cigarettes with full flavour high tar (FF with 23 mg tar) over 1 hour. Initial blood samples from both groups at fasting, followed by further samples from smokers at 1.5 hours and 3 hours after smoking. Initial erythrocyte MDA level and SSA activity were found to be higher in the smoking groups compared to non-smokers. Furthermore, both parameters were significantly higher at the 1.5-hour and 3-hour erythrocyte samples when compared to initial values in the FFLT group. However, there were no statistically significant differences between SSA values established at different times in FF group. Results suggest that smoking causes oxidant load in the erythrocytes. Although a compensatory mechanism (i.e. increased SSA activities) develops in the FFLT group after smoking, this cannot prevent peroxidation reactions (i.e. increased MDA levels) in the erythrocytes. As to the types of cigarettes, both seem to have oxidant potential, but oxidation degree in the FFLT group is higher than that of FF group. These results suggest that antioxidant supplementation to smokers might be beneficial to decrease cellular oxidation damages.

Effects of smoking on plasma and erythrocyte antioxidant defense systems.

In this study, activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) enzymes were measured in the erythrocytes, and levels of thiobarbituric acid-reactive substances (TBARS) and antioxidant potential (AOP) values were measured in both erythrocyte and plasma samples from smokerS and nonsmokers. No significant differences were observed in erythrocyte parameters, serum triglycerides, and total cholesterol. AOP was significantly lower and TBARS level higher in the plasma samples from smokers compared with those of nonsmokers. Results suggest that smoking causes no impairment in the enzymatic antioxidant defense system and does not lead to oxidant stress in the erythrocytes, possibly because these cells have potent antioxidant defense capacity.