Presence Of Oxidative Stress Markers Research Articles

T. Catappa confers an antioxidant effect to electrospun polyvinyl alcohol nanofibers

In this study, the healing process of full-thickness skin wounds induced in Wistar rats (n = 75) was evaluated, divided into 5 treatments: negative control, PVA nanofiber film, and PVA nanofiber film added in concentrations of 3%, 6% and 10% with lyophilized extract of T. catappa. After euthanasia of 5 animals from each of the groups, at times 7, 14 and 21 days, samples were evaluated for the presence of oxidative stress markers reduced Glutathione (GSH) and levels of lipoperoxidation (LPO), and for the histological characteristics of tissues stained with hematoxylin-eosin and azan. The results showed that, in addition to remaining on the surface of the wounds for an acceptable period, the nanofiber membrane was able to deliver the extract of T. catappa to the bed of the treated wounds and, despite not producing statistically relevant histological changes, it was observed significant antioxidant effect by reducing LPO and increasing GSH in a dose dependent manner. Thus, it is concluded that the PVA nanofiber film associated with the T. catappa extract has an antioxidant effect and can assist in wound healing

Determination of Oxidative Stress Markers in the Aqueous Humor and Corneal Tissues of Patients With Congenital Hereditary Endothelial Dystrophy.

The aim of this study is to determine the presence of oxidative stress markers in the aqueous humor (AH) and corneal tissues of patients with congenital hereditary endothelial dystrophy (CHED). Interventional prospective study was undertaken to quantify levels of ascorbic acid and glutathione in the AH of patients with CHED. AH was collected from patients undergoing keratoplasty and levels of ascorbic acid and glutathione were determined using biochemical assays and measured spectrophotometrically. AH collected from pediatric patients with cataract were used as control. Corneal sections of patients who underwent penetrating keratoplasty were obtained, and presence of glutathione peroxidase 1, catalase, and superoxide dismutase was determined by immunohistochemistry. Tissue sections obtained from cadaveric corneas unsuitable for clinical transplant were used as control. Significantly increased ascorbic acid levels were determined in patients with CHED (605.6 ± 158.9 μM) compared with those in controls (190.5 ± 74.72 μM). However, a trend toward reduced level of glutathione was detected in patients with CHED compared with that in the controls. Increased glutathione peroxidase 1 staining and reduced expression of catalase was detected in corneal tissues of patients with CHED compared with those in control corneal tissues. There was no apparent changes observed in the expression of superoxide dismutase in the corneal sections obtained from patients with CHED. To the best of our knowledge, this is the first study to determine the levels of ascorbic acid and glutathione in AH of patients with CHED. Our data suggest the presence of oxidative stress in CHED that might be responsible for the pathological changes in patients with CHED.

Detecting Oxidative Stress Biomarkers in Neurodegenerative Disease Models and Patients.

Oxidative stress is prominent in many neurodegenerative diseases. Along with mitochondrial dysfunction and pathological protein aggregation, increased levels of reactive oxygen and nitrogen species, together with impaired antioxidant defense mechanisms, are frequently observed in Alzheimer’s, Parkinson’s, Huntington’s disease and amyotrophic lateral sclerosis. The presence of oxidative stress markers in patients’ plasma and cerebrospinal fluid may aid early disease diagnoses, as well as provide clues regarding the efficacy of experimental disease-modifying therapies in clinical trials. In preclinical animal models, the detection and localization of oxidatively damaged lipids, proteins and nucleic acids helps to identify most vulnerable neuronal populations and brain areas, and elucidate the molecular pathways and the timeline of pathology progression. Here, we describe the protocol for the detection of oxidative stress markers using immunohistochemistry on formaldehyde-fixed, paraffin-embedded tissue sections, applicable to the analysis of postmortem samples and tissues from animal models. In addition, we provide a simple method for the detection of malondialdehyde in tissue lysates and body fluids, which is useful for screening and the identification of tissues and structures in the nervous system which are most affected by oxidative stress.

Inflammatory mechanisms and oxidative stress in prostatitis: the possible role of antioxidant therapy.

This article focuses on the role that oxidative stress plays in chronic prostatitis, not only with respect to the known impact on symptoms and fertility but also especially in relation to possible prostate cancer development. Prostatitis is the most common urologic disease in adult males younger than 50 years and the third most common urologic diagnosis in males older than 50 years. If the germ-causing acute prostatitis is not eliminated, the inflammatory process becomes chronic. Persistent inflammation causes ongoing production of large quantities of pro-inflammatory cytokines and both oxygen and nitrogen reactive species, with consequent activation of transcription factor nuclear factor-kappa B (NF-κB) and genes encoding for further production of pro-inflammatory cytokines, chemotactic factors, and growth factors. Confirming the role of oxidative stress in chronic prostatitis, several studies have demonstrated the presence of oxidative stress markers in the genital secretions of patients suffering from the disease. Antioxidants can therefore play an essential role in the treatment of chronic bacterial and non-bacterial prostatitis; in the case of bacterial inflammation, they can be associated with antibiotic therapy. Moreover, due to their anti-inflammatory properties, antioxidants hinder the progression of inflammation and the possible development of prostate cancer.

Oocyte oxidative DNA damage may be involved in minimal/mild endometriosis-related infertility.

Early endometriosis is associated with infertility, and oxidative stress may play a role in the pathogenesis of disease-related infertility. This prospective case-control study aimed to compare the presence of oxidative stress markers in the follicular microenvironment and systemic circulation of infertile women with minimal/mild endometriosis (EI/II) versus individuals undergoing controlled ovarian stimulation for intracytoplasmic sperm injection (ICSI). Seventy-one blood samples (27 from infertile women with EI/II and 44 controls with tubal and/or male infertility factor) and 51 follicular fluid samples (19 EI/II and 32 controls) were obtained on the day of oocyte retrieval. Total hydroperoxides (FOX1 ), reduced glutathione, vitamin E, Superoxide dismutase, total antioxidant capacity, malondialdehyde, advanced oxidation protein products, and 8-hydroxy-2'-deoxyguanosine (8OHdG) concentrations were measured in both fluids. Women with EI/II showed higher FOX1 (8.48 ± 1.72 vs. 7.69 ± 1.71 μmol/g protein) and lower total antioxidant capacity (0.38 ± 0.18 vs. 0.46 ± 0.15 mEq Trolox/L) concentrations in serum, and higher 8OHdG concentrations (24.21 ± 8.56 vs. 17.22 ± 5.6 ng/ml) in follicular fluid compared with controls. These data implicate both systemic and follicular oxidative stress may in infertile women with EI/II undergoing controlled ovarian stimulation for ICSI. Furthermore, the elevated 8OHdG concentrations in follicular fluid of women with EI/II may be related to compromised oocyte quality.

Molecular mediators of favism-induced acute kidney injury

Intolerance to fava beans in subjects with glucose-6-phosphate-dehydrogenase deficiency (favism) may lead to severe hemolytic crises and decreased renal function. Renal biopsy findings exploring the molecular mechanisms of renal damage in favism have not been previously reported. We report a case of favism-associated acute kidney injury in which renal biopsy showed acute tubular necrosis and massive iron deposits in tubular cells. Interestingly, iron deposit areas were characterized by the presence of oxidative stress markers (NADPH-p22 phox and heme-oxigenase-1) and macrophages expressing the hemoglobin scavenger receptor CD163. In addition, iron deposits, NADPH-p22 phox, hemeoxigenase- 1 and CD163 positive cells were observed in some glomeruli. These results identify both glomerular and tubular involvement in favism-associated acute kidney injury and suggest novel therapeutic targets to prevent or accelerate recovery from acute kidney injury.

Oxidative stress and successful antioxidant treatment in models of RYR1-related myopathy

The skeletal muscle ryanodine receptor is an essential component of the excitation-contraction coupling apparatus. Mutations in RYR1 are associated with several congenital myopathies (termed RYR1-related myopathies) that are the most common non-dystrophic muscle diseases of childhood. Currently, no treatments exist for these disorders. Although the primary pathogenic abnormality involves defective excitation-contraction coupling, other abnormalities likely play a role in disease pathogenesis. In an effort to discover novel pathogenic mechanisms, we analysed two complementary models of RYR1-related myopathies, the relatively relaxed zebrafish and cultured myotubes from patients with RYR1-related myopathies. Expression array analysis in the zebrafish disclosed significant abnormalities in pathways associated with cellular stress. Subsequent studies focused on oxidative stress in relatively relaxed zebrafish and RYR1-related myopathy myotubes and demonstrated increased oxidant activity, the presence of oxidative stress markers, excessive production of oxidants by mitochondria and diminished survival under oxidant conditions. Exposure to the antioxidant N-acetylcysteine reduced oxidative stress and improved survival in the RYR1-related myopathies human myotubes ex vivo and led to significant restoration of aspects of muscle function in the relatively relaxed zebrafish, thereby confirming its efficacy in vivo. We conclude that oxidative stress is an important pathophysiological mechanism in RYR1-related myopathies and that N-acetylcysteine is a successful treatment modality ex vivo and in a vertebrate disease model. We propose that N-acetylcysteine represents the first potential therapeutic strategy for these debilitating muscle diseases.

SOD1-Targeted Gene Disruption in the Ericoid Mycorrhizal Fungus Oidiodendron maius Reduces Conidiation and the Capacity for Mycorrhization

The genome sequences of mycorrhizal fungi will provide new opportunities for studying the biology and the evolution underlying this symbiotic lifestyle. The generation of null mutants at the wild-type loci is one of the best methods for gene-function assignment in the post-genomic era. To our knowledge, the generation of superoxide dismutase 1 (SOD1)-null mutants in the ericoid mycorrhizal fungus Oidiodendron maius is the first example of a gene-targeted disruption via homologous recombination in a mycorrhizal fungus. The disruption of OmSOD1 by Agrobacterium-mediated transformation resulted in the presence of oxidative stress markers, even in the absence of external superimposed stresses, and an increased sensitivity to reactive oxygen species (ROS)-generating substances, especially to menadione. A reduction in conidiation and in the percentage of mycorrhization of Vaccinium myrtillus roots was also observed. The latter findings establish the pivotal role of SOD1 as an important factor in the relationship between O. maius and its symbiotic partner. The lack of this ROS-scavenger may cause an imbalance in the redox homeostasis during host colonization and an alteration in the delicate dialogue between the fungus and its host plant.

Peroxiredoxin 6 Fails to Limit Phospholipid Peroxidation in Lung from Cftr-Knockout Mice Subjected to Oxidative Challenge

Oxidative stress plays a prominent role in the pathophysiology of cystic fibrosis (CF). Despite the presence of oxidative stress markers and a decreased antioxidant capacity in CF airway lining fluid, few studies have focused on the oxidant/antioxidant balance in CF cells. The aim of the current study was to investigate the cellular levels of reactive oxygen species (ROS), oxidative damage and enzymatic antioxidant defenses in the lung of Cftr-knockout mice in basal conditions and as a response to oxidative insult.The results show that endogenous ROS and lipid peroxidation levels are higher in Cftr −/− lung when compared to wild-type (Cftr +/+) in basal conditions, despite a strong enzymatic antioxidant response involving superoxide dismutases, glutathione peroxidases and peroxiredoxin 6 (Prdx6). The latter has the unique capacity to directly reduce membrane phospholipid hydroperoxides (PL-OOH). A dramatic increase in PL-OOH levels in Cftr −/− lung consecutive to in vivo oxidative challenge by paraquat (PQ) unmasks a susceptibility to phospholipid peroxidation. PQ strongly decreases Prdx6 expression in Cftr −/− mice compared to Cftr +/+. Similar results were obtained after P. aeruginosa LPS challenge. Two-dimensional gel analysis of Prdx6 revealed one main molecular form in basal conditions and a PQ-induced form only detected in Cftr +/+ lung. Mass spectrometry experiments suggested that, as opposed to the main basal form, the one induced by PQ is devoid of overoxidized catalytic Cys47 and could correspond to a fully active form that is not induced in Cftr −/− lung. These results highlight a constitutive redox imbalance and a vulnerability to oxidative insult in Cftr −/− lung and present Prdx6 as a key component in CF antioxidant failure. This impaired PL-OOH detoxification mechanism may enhance oxidative damage and stress-related signaling, contributing to an exaggerated inflammatory response in CF lung.

Differences in oxidative stress dependence between gastric adenocarcinoma subtypes

To investigate the extent of oxidative stress in pre-neoplastic and neoplastic gastric mucosa in relation to their pathological criteria and histological subtypes. A total of 104 gastric adenocarcinomas from 98 patients (88 infiltrative and 16 intraepithelial tumors) were assessed immunohistochemically for expression of iNOS and occurrence of nitrotyrosine (NTYR)-containing proteins and 8-hydroxy-2'-deoxyguanosine (8-OH-dG)-containing DNA, as markers of NO production and damages to protein and DNA. Tumor cells staining for iNOS, NTYR and 8-OH-dG were detected in 41%, 62% and 50% of infiltrative carcinoma, respectively. The three markers were shown for the first time in intraepithelial carcinoma. The expression of iNOS was significantly more frequent in tubular carcinoma (TC) compared to diffuse carcinoma (DC) (54% vs 18%; P = 0.008) or in polymorphous carcinoma (PolyC) (54% vs 21%; P = 0.04). NTYR staining was obviously more often found in TC than that in PolyC (72% vs 30%; P = 0.03). There was a tendency towards a higher rate of iNOS staining when distant metastasis (pM) was present. In infiltrative TC, the presence of oxidative stress markers was not significantly correlated with histological grade, density of inflammation, the depth of infiltration (pT), lymph nodes dissemination (pN) and pathological stages (pTNM). The iNOS-oxidative pathway may play an important role in TC, but moderately in PolyC and DC. DNA oxidation and protein nitration occur in the three subtypes. Based on the significant differences of NTYR levels, TC and PolyC appear as two distinct subtypes.

Apolipoprotein E isoform mediated regulation of nitric oxide release1,2

Progressive dysfunction and death of neurons in Alzheimer’s dementia is enhanced in patients carrying one or more APOE4 alleles who also display increased presence of oxidative stress markers. Modulation of oxidative stress is a nontraditional and physiologically relevant immunomodulatory function of apolipoprotein E (apoE). Stimulated peritoneal macrophages from APOE-transgenic replacement (APOE-TR) mice expressing only human apoE3 or human apoE4 protein isoforms were utilized as mouse models to investigate the role of apoE protein isoforms and gender in the regulation of oxidative stress. Macrophages from male APOE4/4-TR mice produced significantly higher levels of nitric oxide than from male APOE3/3-TR mice, while macrophages from female APOE3/3-TR and female APOE4/4-TR mice produced the similar levels of nitric oxide. Primary cultures of microglial cells of APOE4 transgenic mice also produced significantly more nitric oxide than microglia from APOE3 transgenic mice. These data suggest a potentially novel mechanism for gender-dependent and apoE isoform-dependent immune responses that parallel the genetic susceptibility of APOE4 carriers for the development of Alzheimer’s disease.