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Cornea injury of sulfur mustard (SM) is considered as the most devastating injuries to the eye. This study aimed to evaluate the single and combined effects of N-acetyl cysteine (NAC) and doxycycline on the inflammatory pathway and cornea neovascularization (CNV) in the rat model of SM-injured cornea. The right cornea of male Sprague–Dawley rats was subjected to 2-chloroethyl-ethyl sulfide (CEES). Rats were topically treated with a single and combined of 0.5% NAC and 12.5 μg/ml doxycycline and examined at 3rd, 15th, and 21st days. The activity of three antioxidant enzymes was analyzed in the cornea of different groups. Real-time PCR was performed to measure gene expression of inflammatory factors (tnf-α, rel-a & cxcl-1) and angiogenesis factors (vegf-a, mmp2,9) in the cornea lysates. The histological and opacity assessments were also carried out. The activity of antioxidant enzymes significantly declined 3 days after the CEES damage. NAC eye drop recovered the enzyme activity on the 21st day of treatment (p-value <.05). The expression of tnf-α and rel-a genes significantly increased after CEES cornea exposure, while NAC declined their expression on the 7th and 21st days. The CNV score and angiogenesis factor expression were decreased in the long term by single and combined treatments (p-value <.05), but the infiltration of inflammatory cells was not completely amended. NAC and doxycycline eye drop could improve the CNV complication. Also, NAC was an effective treatment against the inflammatory pathway involved in CEES-injured cornea. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is necessary for the normal function of the male reproductive system and spermatozoa. Although influences of zinc deficiency on impaired spermatogenesis and male infertility have been widely considered, the molecular and cellular mechanisms of these abnormalities are not well understood. General abnormalities, including hypogonadism, Leydig cells damage, deficiency of sex hormone production and impaired spermatogenesis, as well as inflammation, antioxidant depletion, sperm death and male infertility can be observed during zinc deficiency. However, it is not obvious which pathways are relevant to the pathogenesis of zinc deficiency. Oxidative stress (OS) induced by reactive oxygen species is likely as the main mechanism of zinc deficiency which is associated with sperm DNA fragmentation, decrease in sperm membrane integrity, apoptosis, depletion of antioxidants, and consequently poor sperm quality and male infertility. Therefore, identification of these pathways will give valuable information regarding the mechanisms of zinc deficiency on the male reproductive system and the potential way for developing a better clinical approach. In this review, we aim to discuss the proposed cellular and molecular mechanisms of zinc deficiency on the male reproductive system, the importance of OS and mechanisms by which zinc deficiency induces OS and depletion of other antioxidants. [ABSTRACT FROM AUTHOR]

Dysregulation of matrix metalloproteinases (MMPs) is now considered as one of the main toxicity effects of sulfur mustard (SM). Numerous studies have found overexpression of MMPs, but the mechanism is unclear. Accumulation of leukocytes, downregulation of tissue inhibitors of metalloproteinases (TIMPs), increase of pro-inflammatory mediators, as well as massive production of reactive oxygen species (ROS) and oxidative stress (OS) are possible mechanisms by which SM induces MMPs expression long-years after exposure. We aim to discuss cellular and molecular mechanisms of SM toxicity, the importance of MMPs and mechanisms by which SM enhances expression of these proteases in SM-victims. [ABSTRACT FROM AUTHOR]

Sulfur mustard (SM) is a chemical compound that preferentially targets ocular, cutaneous and pulmonary tissues. Although pathologic effect of SM has been extensively considered, molecular and cellular mechanism of its toxicity, especially at the chronic phase of injury is not well-understood. Excessive production of reactive oxygen species (ROS) and oxidative stress (OS) appears to be involved in SM-induced injuries. SM may trigger several molecular and cellular pathways linked to OS and inflammation that can subsequently result in cell death and apoptosis. At the acute phase of injury, SM can enhance ROS production and OS by reducing the activity of antioxidants, depletion of intercellular glutathione (GSH), decreasing the productivity of GSH-dependent antioxidants, mitochondrial deficiency, accumulation of leukocytes and pro-inflammatory cytokines. Overexpression of ROS producing enzymes and down-regulation of antioxidant enzymes are probably the major events by which SM leads to OS at the chronic phase of injury. Therefore, antioxidant therapy with potent antioxidants such as N-acetylcysteine and curcumin may be helpful to mitigate SM-induced OS damages. This review aims to discuss the proposed cellular and molecular mechanisms of acute and delayed SM toxicity, the importance of OS and mechanisms by which SM increases OS either at the acute or chronic phases of injuries along with research on antioxidant therapy as a suitable antidote. [ABSTRACT FROM AUTHOR]

Sulfur mustard (SM) is a mutagenic compound that targets various organs. Although it causes a wide range of abnormalities, cellular and molecular mechanisms of its action are not-well-understood. Oxidation of DNA, proteins, lipids, as well as depletion of cellular nicotinamide adenine dinucleotide (NAD), antioxidants and increase of intracellular calcium are the hypothesized mechanisms of its action at the acute phase of injury. In this review, the proteome analysis of SM toxicity has been considered. We selected articles that considered proteomics analysis of SM toxicity with two-dimensional gel electrophoresis (2DE) followed by mass spectrometry. Our search yielded nine related articles, four original in vitro and five human studies. The results of these studies have revealed a change in expression pattern of various proteins such as haptoglobin, amyloid A1, surfactant proteins, S100 proteins, apolipoprotein, Vit D binding protein, transferrin, alpha 1 antitrypsin, protein disulfide isomerase and antioxidant enzymes in patients who were exposed to SM about 30 years ago. Most of these proteins are up- or down-regulated in response to excessive production of reactive oxygen species (ROS) and oxidative stress (OS). There is a tight link between the expression pattern of these proteins with accumulation of leukocytes, inflammatory conditions, antioxidant depletion, mitochondrial deficiency, as well as increased expression or activity of several proteases such as caspases and matrix metalloproteinases (MMPs). Therefore, excessive production of ROS and OS along with chronic inflammatory may be the long-term toxic effects of SM following acute exposure. [ABSTRACT FROM AUTHOR]

Context: Sulfur mustard (SM) is a lipophilic and reactive chemical compound that targets human airway system. Objective: Glutathione (GSH) depletion, oxidative stress (OS) status, and changes in expression of GSH-dependent antioxidant enzymes were considered in human mustard lungs. Materials and methods: Lung biopsies and bronchoalveolar lavage (BAL) were collected from non-exposed (n = 10) individuals and SM-exposed patients (n = 12). Alterations in expression of GSH-dependent enzymes were studied using RT2 Profiler™ PCR array. OS was evaluated by determining BAL fluid levels of total antioxidant capacity (TAC), malondialdehyde (MDA), and GSH. Results: Mean TAC (0.142 ± 0.027 µmol/l) and GSH (4.98 ± 1.02 nmol/l) in BAL fluids of control group was significantly higher (p < .05) than those in SM-exposed patients (TAC = 0.095 ± 0.018 µmol/l and GSH= 3.09 ± 1.02 nmol/l), while MDA level in BAL fluids of these patients (0.71 ± 0.06 nmol/l) was significantly (p = .001) higher than that in controls (0.49 ± 0.048 nmol/l). Glutathione peroxidases (GPXs), glutathione-s-transferases (GSTs), and glutathione synthetase (GSS) enzymes were overexpressed in mustard lung biopsies, while glutathione reductase (GSR) was significantly downregulated (14.95-fold). Conclusions: GSH depletion induced by GSR downregulation may be a major mechanism of SM toxicity on human lung. Despite overexpression of GSTs and GPXs genes, GSH depletion may decline the productivity of these enzymes and total antioxidants capacity, which is associated with OS. [ABSTRACT FROM AUTHOR]

Mustard lung is a major pulmonary complication in individuals exposed to sulfur mustard (SM) gas during the Iran–Iraq war. It shares common pathological and clinical features with some chronic inflammatory lung disorders, particularly chronic obstructive pulmonary disease (COPD). Airway remodeling, which is one of the main causes of lung dysfunction and the dominant phenomenon of chronic pulmonary diseases, is seen in the mustard lung. Among all mediators involved in the remodeling process, the transforming growth factor (TGF)-β plays a pivotal role in lung fibrosis and consequently in the airway remodeling. Regarding the high levels of this mediator detected in mustard lung patients, in the present study, we have discussed the possible roles of TGF-β in airway remodeling (including epithelial layer damage, subepithelial fibrosis and angiogenesis). Finally, based on TGF-β targeting, we have reviewed new airway remodeling therapeutic approaches. [ABSTRACT FROM AUTHOR]

Despite the attention to the different systems damaged by sulfur mustard(SM), little attention has been paid to the immune system. But, after years following the injury, the immune system dysfunction is discussed as the main cause of death in veterans. Also, the study of inflammatory and pro-inflammatory markers in these patients has not been evaluated at the time of exposure and the acute phase of the disease. Therefore, to gain more information about the inflammatory mechanisms of SM, we proposed to examine the patients in the acute phase and evaluate the inflammatory and pre-inflammatory factors at the beginning of exposure. [ABSTRACT FROM PUBLISHER]

Respiratory disorders in sulfur mustard (SM)-exposed and chronic obstructive pulmonary disease (COPD) patients are mostly associated with neutrophilic inflammation, severe airflow limitation, and oxidative stress. The objective of this study was to establish whether neutrophil (PMN) proteomes in these diseases were similar or differed. Blood neutrophil proteomes from healthy, SM-exposed, and COPD subjects were analyzed using two-dimensional gel electrophoresis followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOF MS). Elastase activity was determined kinetically. The results showed that levels of S100 calcium-binding protein (CBP) A12, S100 CBP A8, glyceraldehyde-3-phosphate dehy-drogenase, superoxide dismutase, and protein disulfide isomerase proteins - as well as elastase activity - were significantly increased in PMN from 'diseased' hosts compared to in cells from healthy controls. In contrast, coactosin-like protein, RhoGDP dissociation inhibitor, and actin isoforms were significantly decreased in diseased subjects' PMN compared to PMN of healthy controls. Moreover, serpin B1 and coronin-1A were expressed only in PMN of the healthy subjects. Lastly, S100 CBP A9, endoplasmic reticulum (ER)-60 protease, and glutathione- S-transferase isoforms were differentially expressed in the cells from the SM-exposed and COPD subjects. These results show that serpin B1, an efficient inhibitor of neutrophil serine proteases, was not detectable, and elastase activity significantly increased in PMN from both SM-exposed and COPD patients. It seems that, apart from inflammation and oxidative stress, a protease:anti-protease imbalance exists within PMN of both COPD and SM-exposed patients. [ABSTRACT FROM AUTHOR]