Background:Matrix metalloproteinases (MMPs) are a group of endopeptidases which comprised of various types. These proteolytic enzymes are zinc-dependent and play role in degradation of extracellular matrix (ECM). Various types of cells such as macrophages, fibroblasts, neutrophils, synovial cells and some epithelial cells secrete MMPs. According to previous studies on bronchiolitis and respiratory tract lesions in these patients and unknown pathophysiology mechanism up to date, this cross–sectional study was performed.Objectives:The aim of this study was to compare the serum MMP level in patients with chemical injuries and normal people and also determine the role of these parameters in pulmonary disorders .Materials and Methods:In this cross–sectional study, 25 Iranian patients exposed to the sulfur mustard and 25 unexposed participants as the control group were enrolled. Serum samples were collected from two groups and stored at -70˚C until the measurement of MMPs and TIMPs. ELISA kit was used for measurement of MMP and TIMP based on the kit's instruction. For validations in measurement, all samples were analyzed duplicate and in some cases triplicate.Results:The mean level of MMP-9 in serum of chemically-injured group was 1592.42 and this amount in normal group was 679.72 .So there was a significant difference between two groups (P = 0.001) and the mean level of MMP-8 in serum of patients group was 49.10 and in normal group was 35.53. Then there was no significant difference between two groups (P = 0.197). The mean levels of MMP-1 and MMP-2 was not significantly different (P value > 0.05) in the patient and normal groups. And also the mean levels of TIMP-1 and TIMP-2 was not significantly different (P > 0.05) in the patients and normal groups.Conclusions:In summary, serum MMPs in chemically-injured has shown no significant difference with normal people except for the MMP-9.

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Sulfur mustard (SM) is an alkalizing chemical which has been used mostly as a weapon all over the world. Sulfur mustard can cause damages to many organs, especially the skin, respiratory system and the eyes. Generally, many complications of mustard gas result from its alkalizing potency and reaction with cellular components like DNA, RNA, proteins and lipid membranes. The damages caused by SM will lead to many complications which persist during the lifespan of exposed subjects. Pro-inflammatory cytokines including especially TNF-α and IL-1β can cause systemic inflammatory reactions and vast changes like altered cell signaling, migration, cytokine production changes and fever. This study was designed to analyze cytokine levels in mustardgas-exposed people's serum in the war between Iraq and Iran, who had the chronic dry-eye symptoms compared to the normal group, 30 years after exposure. In this study, 25 veterans who were exposed to mustard gas were compared to 25 healthy people as control group. The veterans with concurrent involvement of eye, lung, and skin were selected. We used ELISA method to assess the levels of TNF-α and IL-1β in serum of people in both groups. All the results analyzed with T-test in SPSS 17 statistical software. The mean levels of TNF-α and IL-1β in serum of chemical exposed veterans were 52.3 ± 1.4 pg/ml and 3.43 ± 0.3 pg/ml while in the control group were 19.5±1.3 pg/ml and 2.25 ± 0.2 pg/ml, respectively. In the control group, the serum pro-inflammatory cytokine levels were significantly lower than the exposed group (P < 0.05). This study showed that there is a meaningful difference be-