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Cigarette smoke (CS) is an important source of reactive nitrogen species (RNS). It has been demonstrated that CS constitutes the highest source of exogenous nitric oxide and peroxynitrite to which humans are exposed. NF-kappaB is a key inflammatory, redox-sensitive transcription factor, which role in CS-induced airway inflammation is unclear. Moreover, the role of RNS in the activation of NF-kappaB and in inflammation has remained vague. This study investigated CS-induced NF-kappaB activation in human lymphocytes and assessed the involvement of CS-derived RNS in NF-kappaB activation and their possible biological effects. Mild, but not high, exposure to CS induced NF-kappaB in lymphocytes through IKK activation, I-kappaBalpha degradation, and the reduction in the intracellular glutathione levels. Peroxynitrite, but not NO, mimicked the effects of CS on NF-kappaB. Reduction of intracellular peroxynitrite formation by the inhibition of the mitochondrial respiratory chain resulted in decreased activation of NF-kappaB by CS. NF-kappaB-induced iNOS levels were increased in response to CS. Low levels of CS exposure induced classical NF-kappaB activation pathway in lymphocytes via intracellular formation of peroxynitrite, through a reaction between smoke-derived NO and endogenously produced superoxide. This NF-kappaB activation resulted in inflammatory gene expression, which may contribute to CS-related airway inflammation.

Cigarette smoking is linked to various human disorders. Active and passive smokers suffer from inflammatory diseases of lungs and airways. Smoking-dependent airway inflammation is related to the cytotoxic effects of cigarette smoke (CS) and chronic recruitment of neutrophils and macrophages. NF-kappaB is a key inflammatory, redox-sensitive transcription factor. Its role in CS-induced airway inflammation is unclear. This study investigated CS-induced NF-kappaB activation in human lymphocytes and the possible involvement of oxidative insult in this activation. A method for accurate and reproducible exposure of lymphocytes to CS was developed. The intensity of CS exposure was linearly correlated with nitrite concentration originating from reactive oxygen species in CS. Mild, but not high exposure to CS, induced NF-kappaB in lymphocytes through the increase in oxidative stress and the reduction in the intracellular glutathione levels. These findings may have implications to active as well as to passive smokers, suffering from inflammatory diseases of lungs and airways.

Introduction: The mortality rate in diabetic dialysis patients (DDPs) is over 15% per year, with the cause of death most often attributed to cardiovascular disease (CVD) or bacterial infection (sepsis). Identification of genetic markers predictive of early mortality would be useful in the evaluation of therapies for the reduction of mortality rate in this population. Haptoglobin (Hp) is a polymorphic protein which appears to confer differential susceptibility to bacterial infection and CVD. We therefore proposed that Hp phenotype can predict mortality in DDPs., Methods: We tested this hypothesis prospectively in a longitudinal study of 392 dialysis patients from eight medical centres in Israel. Hp was determined by polyacrylamide gel electrophoresis. Patients were followed for all-cause mortality over a 3-year period., Results: We found that Hp phenotype was a significant predictor of mortality in DDPs stratified by age. In diabetic individuals over 60 years of age there was a decrease in mortality associated with the Hp 1-1 phenotype (P = 0.03). However, in younger DDPs the Hp 2-2 phenotype was associated with a decreased mortality rate (P = 0.003)., Conclusion: Hp phenotype may be useful in the risk stratification algorithm and management of DDPs.

Background: We recently reported that haptoglobin (Hp) phenotype 1-1 is protective against the development of nephropathy in normal creatinine diabetics. In the present study, we sought to determine if Hp phenotype also plays a role in renal deterioration by determining Hp phenotypes in a consecutive series of patients with chronic renal failure (CRF) in hemodialysis (HD) and predialysis clinics., Methods: Three hundred and ninety-two patients on HD for less than 2 years and 182 predialysis patients (creatinine clearance time [CCT] <35 ml/min) were subjected to Hp phenotyping. Age, gender and presence of diabetes or hypertension were recorded. Patients were stratified according to age (above and below 60 years) and severity of renal dysfunction (CRF or HD)., Results: We observed a markedly lower prevalence of the Hp 1-1 phenotype in HD patients under 60 years of age compared to patients with CRF or compared to the general population. This was not due to differences in the threshold for dialysis initiation among patients with different Hp types or to decreased survival of patients with Hp 1-1 prior to entering HD. In HD patients 60 years and over, Hp 1-1 prevalence was increased, as observed with other diseases in this age group., Conclusions: The prevalence of Hp 1-1 is decreased in HD patients less than 60 years of age. This may be due to a fundamental difference in the rate of renal deterioration in patients with different Hp types. In addition, Hp 1-1 may provide a protective effect against mortality in elderly patients., (Copyright 2004 S. Karger AG, Basel)

Natural stable isotope fractionation is a potential tool in investigation of metabolic process, since rigid mass balance considerations rule the changes in the isotopic ratio. As the natural changes in 13C/12C ratio of total CO2 between blood and urine served for studying renal bicarbonate reabsorption, studying changes in 18O/16O ratio of phosphate are suggested to investigate deranged phosphate metabolism. The 18O/16O ratio in serum phosphate is constant, determined by the ratio in the environmental drinking water. Therefore, measurements of this ratio in normal individuals, after modifications in phosphate metabolism and in diseases with high alkaline phosphatase activity are proposed. The main purpose of the proposed study is to assess whether measurements of 18O/16O ratio can detect malignant metastases in bones due to deranged phosphate metabolism. An assumption that these determinations might precede other tests for detecting bone metastases and can serve as an oncogenic marker is made.