73 research outputs found
Oxidative stress in the pathogenesis of systemic scleroderma: An overview
Systemic sclerosis (SSc) is a rare disorder of the connective tissue characterized by fibrosis of the skin, skeletal muscles and visceral organs. Additional manifestations include activation of the immune system and vascular injury. SSc causes disability and death as the result of end-stage organ failure. Two clinical subsets of the SSc are accepted: limited cutaneous SSc (lc-SSc) and diffuse cutaneous SSc (dc-SSc). At present, the aetiology and pathogenesis of SSc remain obscure, and consequently, disease outcome is unpredictable. Numerous studies suggest that reactive oxidizing species (ROS) play an important role in the pathogenesis of scleroderma. Over the years, several reports have supported this hypothesis for both lc-SSc and dc-SSc, although the specific role of oxidative stress in the pathogenesis of vascular injury and fibrosis remains to be clarified. The aim of the present review was to report and comment the recent findings regarding the involvement and role of oxidative stress in SSc pathogenesis. Biomarkers proving the link between ROS and the main pathological features of SSc have been summarized
The effect of sleeve gastrectomy on oxidative stress in obesity
High concentrations of free radicals are present in the blood of obese patients. Free radicals are associated with endothelial dysfunction, diabetes, and neoplastic transformation, all conditions that are closely related to obesity. The purpose of our study was to determine whether bariatric surgery modifies the production of free radicals in obese patients. In total, 20 patients with morbid obesity, who were candidates for laparoscopic sleeve gastrectomy (SG), and 18 controls were enrolled in the study. Oxidative stress was studied in obese subjects before and after sleeve gastrectomy. The evaluation of oxidative stress was carried out on blood samples using electron paramagnetic resonance, a refined spectroscopic technique used to identify and quantify the major free radicals, such as •OH, O2•, ONOO-, and NO. Oxidative stress was higher in subjects with morbid obesity prior to surgery, compared to the controls (CP• 9.9 ± 0.3 µM vs. 5.8 ± 0.2 µM). After SG, values decreased to levels comparable to those of controls (CP• 5.4 ± 0.2 µM). Further analysis identified O2• as the main free radical responsible for the oxidative stress. Obesity is associated with an increased blood concentration of free radicals. The normalization of free radicals after sleeve gastrectomy highlights another important benefit of this bariatric surgery technique
A possible role for selenoprotein glutathione peroxidase (GPx1) and thioredoxin reductases (TrxR1) in thyroid cancer. Our experience in thyroid surgery
Abstract
Background: Oxidative stress is responsible for some alterations in the chemical structure and, consequently, in
the function of proteins, lipids, and DNA. Recent studies have linked oxidative stress to cancers, particularly thyroid
cancer, but the mechanisms remain unclear. Here, we further characterize the role of oxidative stress in thyroid cancer
by analyzing the expression of two selenium antioxidant molecules, glutathione peroxidase (GPx1) and thioredoxin
reductase (TrxR1) in thyroid cancer cells.
Methods: Samples of both healthy thyroid tissue and thyroid tumor were taken for analysis after total thyroidectomy.
The expression of GPx1 and TrxR1 was revealed by Western blot analysis and quantified by densitometric analyses,
while the evaluation of free radicals was performed by Electron Paramagnetic Resonance (EPR)-spin trapping
technique.
Results: Our results show a decrease in the expression of GPx1 and TrxR1 (− 45.7 and − 43.2% respectively, p < 0.01)
in the thyroid cancer cells compared to the healthy cells. In addition, the EPR technique shows an increase of free
radicals in tumor tissue, significantly higher than that found in healthy thyroid tissue (+ 116.3%, p < 0.01).
Conclusions: Our findings underscore the relationship between thyroid cancer and oxidative stress, showing the
imbalance of the oxidant/antioxidant system in thyroid cancer tissue. These results suggest that either the inability to
produce adequate antioxidant defense or an increased consumption of antioxidants, due to the hyper-production of
free radicals, may play a crucial role in thyroid cancer.
Keywords: Oxidative stress, Thyroid cancer, Glutathione peroxidase (GPx1), Thioredoxin reductases (TrxR1), Selenium
enzyme
Sex-related biomarkers in cardiovascular and neurodegenerative disorders
Despite considerable advances in the treatment of human inflammatory diseases, such as cardiovascular and neurological disorders, they remain the leading cause of death in developed countries. From a clinical perspective, an active area of investigation focuses on the identification of diagnostic and prognostic biomarkers, because preventing events in those at risk of chronic inflammatory disease is likely to have a substantial impact on the overall public-health burden. The sex difference has not been considered previously as important in the evaluation of biomarkers of human diseases, twithstanding it is now ascertained that the severity of these disorders is correlated with sex hormones which modulate the inflammatory response. The aim of the present brief review is to report and comment the state of art regarding the sex-related biomarkers in cardiovascular and neurodegenerative disorders, focusing on those compounds showing potential prognosticand diagnostic values, and/or acting as indicators of the therapeutic treatment efficacy
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