These results suggest that the GSTT1 and GSTM1 null genotypes and the GSTP1 Val/Val polymorphism may play important roles in asthma pathogenesis. It is possible that intermediate electrophilic metabolites, arising in the first phase of detoxification, are not metabolized by GST enzymes in asthmatic patients and are not excreted. These intermediate metabolites may damage cells and generate oxidative stress, and so contribute to the pathogenesis of asthma.

Apoptotic loss of parenchymal cells may lead to organ dysfunctions in critically ill patients with septic states. As an antioxidant, the protective effects of N-acetylcysteine (NAC) are documented in many experimental and clinical studies. In this experimental study, we investigated the role of chronically used NAC in septic lung injury on a cecal ligation and puncture (CLP) model. To evaluate this, 30 male Wistar rats were randomly divided into four groups as sham (n = 7), CLP (n = 8), sham + NAC (n = 7) and CLP + NAC (n = 8) groups. NAC was administered 150 mg kg(-1) day through intramuscular route beginning 6 h after the operations and lasting for a period of 1 week. One week later, histopathology and epithelial apoptosis were assessed by hematoxylin-eosin and immunohistochemically by M30 and caspase 3 staining to demonstrate septic lung injury. Additionally, lung tissue myeloperoxidase (MPO) activity, malondialdehyde (MDA), and nitrite/nitrate levels were measured. The MPO activity and MDA levels in lung homogenates were found to be increased in CLP group and the administration of NAC prevented their increase significantly (P < 0.05). However, there were no significant differences among the groups regarding nitrite/nitrate levels. The number of apoptotic cells was significantly lower in CLP+NAC group than CLP group, and this finding was supported by M30 and caspase 3 expression in lung (P < 0.05). Lung histopathology was also protected by NAC in CLP-induced sepsis. In conclusion, the chronic use of NAC inhibited MPO activity and lipid peroxidation, which resulted in reduction of apoptosis in lung in this CLP model. Because lung tissue nitrite/nitrate levels did not change significantly, organs other than the lungs may be responsible for producing the increased nitric oxide during sepsis. The chronic use of NAC needs further investigation for its possible antiapoptotic potential in septic states besides its documented antioxidant and antiinflammatory effects.

Background: Leptin is a protein mainly secreted by adipocytes, and the major function of leptin was its role in body weight regulation. In humans, there was a strong correlation between leptin and nutritional parameters, such as body mass index (BMI) and fat mass (FM). Administration of recombinant leptin to ob/ob mice, which have a genetic defect in leptin production, reduces food intake, increases energy expenditure, and decreases body weight. It is suggested that increased levels of circulating leptin levels may contribute to anorexia and weight loss in pathologic conditions including chronic obstructive pulmonary disease (COPD). Recent studies have provided evidence for a link between leptin and proinflammatory cytokines such as TNF-α. Objective: This study aimed to detect serum leptin and TNF-α levels in COPD patients without weight loss during stable disease and acute exacerbation, and to investigate relationships between leptin, TNF-α and nutritional parameters at different stages of the disease. Material and Methods: 26 stable COPD patients, 16 COPD patients with acute exacerbation and 15 control subjects participated in this study. To eliminate the effects of sex differences, all patients and controls were male. BMI, percent ideal body weight, percent FM, sum of skinfold tickness and serum leptin and TNF-α levels were measured in all participants. Leptin and TNF-α levels were measured by ELISA. Results: Serum leptin and TNF-α levels were significantly higher in the patients experiencing exacerbation than in the stable patients and controls. Although leptin levels were lower and TNF-α levels were higher in the stable patient group than in the controls, these differences were not statistically different. Leptin levels were significantly correlated with the nutritional parameters in both control and stable groups. However, in patients with acute exacerbation, a correlation between leptin and nutritional parameters was not found. There was no significant relationship between TNF-α and nutritional parameters in the three groups. In addition, while there was no correlation between leptin and TNF-α levels in the stable and control groups, a significant positive correlation was observed in patients with exacerbation. Conclusion: In conclusion (1) elevated TNF-α levels may be related to increased inflammation in patients, (2) circulating TNF-α levels were associated with increased leptin levels and (3) although leptin and nutritional parameters were correlated in the stable COPD patients, the correlation was weaker compared to controls, and during an exacerbation it disappeared completely. Therefore, inappropriately increased levels of leptin and TNF-α noted during recurrent acute exacerbations in patients with COPD may lead to changes in nutritional parameters and body weight in the course of the disease.

The effects of cadmium on performance, antioxidant defense system, liver and kidney functions, and cadmium accumulation in selected tissues of broiler chickens were studied. Whether the possible adverse effects of cadmium would reverse with the antioxidant ascorbic acid was also investigated. Hence, 4 treatment groups (3 replicates of 10 chicks each) were designed in the study: control, ascorbic acid, cadmium, and cadmium plus ascorbic acid. Cadmium was given via the drinking water at a concentration of 25 mg/L for 6 wk. Ascorbic acid was added to the basal diet at 200 mg/kg either alone or with cadmium. Cadmium decreased the body weight (BW), body weight gain (BWG), and feed efficiency (FE) significantly at the end of the experiment, whereas its effect on feed consumption (FC) was not significant. Cadmium increased the plasma malondialdehyde (MDA) level as an indicator of lipid peroxidation and lowered the activity of blood superoxide dismutase (SOD). Liver function enzymes, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and gamma glutamyl transferase (GGT) activities were not changed by cadmium. Cadmium ingestion did not alter serum creatinine levels. Although the serum cadmium level was not elevated, cadmium mainly accumulated in the kidneys, liver, pancreas, and muscle. Ascorbic acid supplementation resulted in a reduction of MDA level previously increased by cadmium and a restoration in SOD activity. However, ascorbic acid did not ameliorate the growth inhibitory effect of cadmium nor did it prevent accumulation of cadmium in analyzed tissues. These data indicate that oxidative stress, induced by cadmium, plays a role in decreasing the performance of broilers and that dietary supplementation by ascorbic acid might be useful in reversing the lipid peroxidation induced by cadmium and partly alleviating the adverse effect of cadmium on performance of broilers.

Hyperhomocysteinemia, a well-known and independent risk factor for cardiovascular disease, has been related in several studies with psoriasis patients. It has been suggested that homocysteine leads to endothelial dysfunction by causing an accumulation of asymmetrical dimethyl arginine (ADMA), a potent endogenous nitric oxide (NO) synthase inhibitor of the L-arginine-NO pathway. However, limited data is available regarding the psoriasis and ADMA relationship. In this study, we aimed to investigate the serum levels of homocysteine, ADMA and other metabolites from the L-arginine-NO pathway in psoriasis patients. Forty-two patients with chronic plaque psoriasis and 48 controls were enrolled in the study. Serum homocysteine, ADMA, L-monomethyl-L-arginine (L-NMMA), symmetric dimethylarginine (SDMA) and L-arginine levels, and L-arginine/ADMA ratios of psoriasis patients and the control group were measured. The severity of psoriasis was assessed by the psoriasis area and severity index (PASI). The mean ADMA and homocysteine values were significantly higher, and citrulline and L-arginine/ADMA values were significantly lower in psoriasis patients compared to control subjects. However, there were no significant differences among the patient and control groups with respect to mean SDMA, L-NMMA and L-arginine values. PASI scores strongly correlated with the ADMA level and moderately correlated with L-arginine/ADMA ratio. This study suggests that the L-arginine-NO pathway metabolites, especially ADMA, may play an important role in the pathogenesis of psoriasis. Additionally, serum ADMA levels of psoriasis patients may be an indicator of the disease severity.