Immune system-mediated endothelial damage is associated with NO and antioxidant system disorders

A transcriptomics-based analysis of the toxicity mechanisms of gabapentin to zebrafish embryos at realistic environmental concentrations

Gabapentin (GPT) has become an emerging contaminant in aquatic environments due to its wide application in medical treatment all over the world. In this study, embryos of zebrafish were exposed to gabapentin at realistically environmental concentrations, 0.1 μg/L and 10 μg/L, so as to evaluate the ecotoxicity of this emergent contaminant. The transcriptomics profiling of deep sequencing was employed to illustrate the mechanisms. The zebrafish (Danio rerio) embryo were exposed to GPT from 12 hpf to 96 hpf resulting in 136 and 750 genes differentially expressed, respectively. The results of gene ontology (GO) analysis and the Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis illustrated that a large amount of differentially expressed genes (DEGs) were involved in the antioxidant system, the immune system and the nervous system. RT-qPCR was applied to validate the results of RNA-seq, which provided direct evidence that the selected genes involved in those systems mentioned above were all down-regulated. Acetylcholinesterase (AChE), lysozyme (LZM) and the content of C-reactive protein (CRP) were decreased at the end of exposure, which is consistent with the transcriptomics results. The overall results of this study demonstrate that GPT simultaneously affects various vital functionalities of zebrafish at early developmental stage, even at environmentally relevant concentrations.

Antioxidative Enzyme Activities and Lipid Peroxidation in Children with Inflammatory Endothelial Injury

During the inflammatory process endothelial cells are activated and a proadherent ability is assumed. The synthesis of reactive oxygen metabolites, which follows the immunological processes, can cause oxidative damage to endothelial cells leading to the clinical expression of disease including a variety of skin manifestations. In this study the activity of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase) and the malondialdehyde concentration were examined in 36 children with inflammation-mediated damage to microvascular endothelial cells. On the basis of clinical manifestations the studied children were divided into 4 groups (1st group-macular skin manifestations, 2nd group-maculo-papular skin manifestations, 3rd group-papular skin manifestations, 4th group- erythematous skin manifestations). All the examined children showed symptoms of inflammation (mainly respiratory tract infections) with leukocytosis and monocytosis before actual skin manifestations took place. Superoxide dismutase activity was significantly decreased in three groups of patients, except in the group with erythematous skin manifestations. Catalase activity was significantly increased in all the groups compared to the control group. The values of malondialdehyde were significantly increased in the groups of children with maculo-papular and erythematous skin manifestations. The results have confirmed the presence of a changed antioxidant enzyme pattern indicating oxidative stress during inflammatory endothelial cells injury. Malondialdehyde was not an adequate parameter in its evaluation.

Markers of oxidative and nitrosative stress in systemic lupus erythematosus: correlation with disease activity

OBJECTIVE

Free radical-mediated reactions have been implicated as contributors in a number of autoimmune diseases, including systemic lupus erythematosus (SLE). However, the potential for oxidative/nitrosative stress to elicit an autoimmune response or to contribute to disease pathogenesis, and thus be useful when determining a prognosis, remains largely unexplored in humans. This study was undertaken to investigate the status and contribution of oxidative/nitrosative stress in patients with SLE.

METHODS

Sera from 72 SLE patients with varying levels of disease activity according to the SLE Disease Activity Index (SLEDAI) and 36 age- and sex-matched healthy controls were evaluated for serum levels of oxidative/nitrosative stress markers, including antibodies to malondialdehyde (anti-MDA) protein adducts and to 4-hydroxynonenal (anti-HNE) protein adducts, MDA/HNE protein adducts, superoxide dismutase (SOD), nitrotyrosine (NT), and inducible nitric oxide synthase (iNOS).

RESULTS

Serum analysis showed significantly higher levels of both anti-MDA/anti-HNE protein adduct antibodies and MDA/HNE protein adducts in SLE patients compared with healthy controls. Interestingly, not only was there an increased number of subjects positive for anti-MDA or anti-HNE antibodies, but also the levels of both of these antibodies were statistically significantly higher among SLE patients whose SLEDAI scores were > or = 6 as compared with SLE patients with lower SLEDAI scores (SLEDAI score <6). In addition, a significant correlation was observed between the levels of anti-MDA or anti-HNE antibodies and the SLEDAI score (r = 0.734 and r = 0.647, respectively), suggesting a possible causal relationship between these antibodies and SLE. Furthermore, sera from SLE patients had lower levels of SOD and higher levels of iNOS and NT compared with healthy control sera.

CONCLUSION

These findings support an association between oxidative/nitrosative stress and SLE. The stronger response observed in serum samples from patients with higher SLEDAI scores suggests that markers of oxidative/nitrosative stress may be useful in evaluating the progression of SLE and in elucidating the mechanisms of disease pathogenesis.