Article

Nitric oxide synthesis is increased in patients with systemic lupus erythematosus.

Department of Internal Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Rheumatology International (Impact Factor: 2.21). 01/1998; 18(2):41-3. DOI: 10.1007/s002960050055
Source: PubMed

ABSTRACT Nitric oxide (NO) is believed to have a role in the inflammatory process. NO production was measured in 26 patients with systemic lupus erythematosus (SLE) and 20 healthy volunteers, using spectrophotometrically determined serum nitrite and citrulline as surrogate markers. Both nitrite and citrulline levels were significantly higher in patients with SLE than in controls (P < 0.001). Twelve and 10 patients, respectively, with SLE had nitrite and citrulline levels that were two standard deviations higher than the mean level of controls. These patients had a significantly higher measure of disease activity (SLE Disease Activity Index). These data show that there is increased NO production in SLE and that it may serve as a marker for disease activity.

0 Bookmarks
 · 
54 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Peroxynitrite is a bifaceted reactive species. It can oxidize and nitrate proteins/nucleic acids/lipids and is involved in inflammation, apoptosis, cytotoxicity and autoimmune disorders of unknown etiology, including SLE. In this study, H3 histone exposed to peroxynitrite caused loss of tertiary structure, nitration of tyrosine residues and dityrosine formation. Experimentally produced antibodies against peroxynitrite-modified H3 histone showed specificity for the immunogen. However, cross-reactions with other nitrated proteins were also observed. We further investigated the binding of SLE autoantibodies with native DNA, native H3 histone and peroxynitrite-modified H3 histone to explore the possible role of modified-H3 histone in the initiation and/or progression of SLE in a sub-group of patients. The results showed preferential binding of SLE anti-nDNA autoantibodies to peroxynitrite-modified H3 histone. The visual detection of immune complex formation with native and peroxynitrite-modified H3 histone reiterated preferential binding of SLE autoantibodies with modified H3 histone. It may be concluded that anti-histone autoantibodies seen in a sub-group of SLE patients might be due to the immunogenicity of peroxynitrite-modified H3 histone.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Exposure to trichloroethene (TCE), a ubiquitous environmental contaminant, has been linked to a variety of autoimmune diseases (ADs) including SLE, scleroderma and hepatitis. Mechanisms involved in the pathogenesis of ADs are largely unknown. Earlier studies from our laboratory in MRL+/+ mice suggested the contribution of oxidative/nitrosative stress in TCE-induced autoimmunity, and N-acetylcysteine (NAC) supplementation provided protection by attenuating oxidative stress. This study was undertaken to further evaluate the contribution of nitrosative stress in TCE-mediated autoimmunity and to identify proteins susceptible to nitrosative stress. Groups of female MRL +/+ mice were given TCE, NAC or TCE + NAC for 6 weeks (TCE, 10 mmol/kg, i.p., every 4th day; NAC, ∼250 mg/kg/day via drinking water). TCE exposure led to significant increases in serum anti-nuclear and anti-histone antibodies together with significant induction of iNOS and increased formation of nitrotyrosine (NT) in sera and livers. Proteomic analysis identified 14 additional nitrated proteins in the livers of TCE-treated mice. Furthermore, TCE exposure led to decreased GSH levels and increased activation of NF-κB. Remarkably, NAC supplementation not only ameliorated TCE-induced nitrosative stress as evident from decreased iNOS, NT, nitrated proteins, NF-κB p65 activation and increased GSH levels, but also the markers of autoimmunity, as evident from decreased levels of autoantibodies in the sera. These findings provide support to the role of nitrosative stress in TCE-mediated autoimmune response and identify specific nitrated proteins which could have autoimmune potential. Attenuation of TCE-induced autoimmunity in mice by NAC provides an approach for designing therapeutic strategies.
    PLoS ONE 01/2014; 9(6):e98660. · 3.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disease whose etiology remains largely unknown. The uncontrolled oxidative stress in SLE contributes to functional oxidative modifications of cellular protein, lipid and DNA and consequences of oxidative modification play a crucial role in immunomodulation and trigger autoimmunity. Measurements of oxidative modified protein, lipid and DNA in biological samples from SLE patients may assist in the elucidation of the pathophysiological mechanisms of the oxidative stress-related damage, the prediction of disease prognosis and the selection of adequate treatment in the early stage of disease. Application of these biomarkers in disease may indicate the early effectiveness of the therapy. This review is intended to provide an overview of various reactive oxygen species (ROS) formed during the state of disease and their biomarkers linking with disease. The first part of the review presents biochemistry and pathophysiology of ROS and antioxidant system in disease. The second part of the review discusses the recent development of oxidative stress biomarkers that relates pathogenesis in SLE patients and animal model. Finally, this review also describes the reported clinical trials of antioxidant in the disease that have evaluated the efficacy of antioxidant in the management of disease with ongoing conventional therapy.
    Journal of Biomedical Science 03/2014; 21(1):23. · 2.46 Impact Factor