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Abstract Background and objectives: Smokers are exposed to significant quantities of ROS (Reactive Oxygen Species) and The Level of Nitric Oxide (NO), the primary vasodilator produced by endothelial cells, is changed by cigarette smoking. Cigarette smoking is associated with impaired endothelium-dependent vasodilatation and cardiovascular disease (CVD). The aim of this study is to determine the level of serum nitrite, nitrate and malondialdehyde (MDA) levels in smokers. Material and Methods: In this descriptive analytical study, 60 healthy male smokers and 60 male non-smokers (control group) were selected by a Purposive sampling and then serum levels of nitrite, nitrate and MDA in all patients were determined and compared to together. Results: Serum nitrite and nitrate level in smokers are 10.4±3.1 and 19.6±5.9 and in non-smokers is 14.6±4.4 and 29.3±6.7 (p<0.00001) μmol/L, respectively. The results show that smokers’ are significantly lower than non-smokers’. Serum MDA level in smokers (11.7±2.6 μmol/L) is significantly higher (p<0.00001) than non-smokers (8.3±1.9 μmol/L). Conclusion: Based on the results, serum level of nitrite and nitrate are lower and MDA is higher in smokers. This difference can be related to CVD in smokers. Keywords: Smokers, Non-smokers, Nitrite, Nitrate, Malodialdehyde (MDA), cardiovascular disease (CVD).

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Background and objectives:  Oxidative stress is the most important pathophysiological cause of diseases. Studies have shown that exercise and supplementation with medicinal plants have limited side effects. The aim of the present study was to evaluate effects of aerobic exercise and ethanolic extract of purslane seed on ATP, O-6-Methylguanine DNA methyltransferase (MGMT), malondialdehyde (MDA) and prooxidant-antioxidant balance (PAB) levels in the heart tissue of rats poisoned with hydrogen peroxide.
Methods: In this experimental trial, 72 male Wistar rats were randomly divided into nine groups: (1) control + H₂O₂ , (2) aerobic exercise, (3) aerobic exercise and 50 mg/kg purslane seed extract, (4) aerobic exercise and 200 mg/kg purslane seed extract, (5) aerobic exercise and 400 mg/kg purslane seed extract, (6) 50 mg/kg purslane seed extract, (7) 200 mg/kg purslane seed extract, (8) 400 mg/kg purslane seed extract, and (9) healthy control. Oxidative stress was induced by intraperitoneal injection of 1 mmol/kg hydrogen peroxide three times a week for eight weeks. Aerobic exercise was performed three sessions a week for eight weeks, and the purslane seed extract was intraperitoneally injected daily at the mentioned doses.
Results: Aerobic exercise and purslane seed extract alone or combined significantly increased ATP, MGMT and significantly reduced MDA and PAB levels in cardiac tissue of rats exposed to hydrogen peroxide (P<0.05). Moreover, the effect of purslane seed extract was dose dependent.
Conclusion: It seems that aerobic exercise and purslane seed extract supplementation have synergistic cardioprotective effects under oxidative stress.

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Samaneh Sabouri , Darioush Hamidi Alamdari , Sanaz Salaramoli , Seyyed Isaac Hashemy
Background: Multiple sclerosis (MS) is a demyelination disorder of the central nervous system (CNS), which is believed to be associated with oxidative stress. Therefore, researchers try to find reliable biomarkers to monitor the disease and predict its prognosis. Cholesterol and lipids in the myelin sheath are vital for nerve cells. Serum low-density lipoprotein (LDL) is susceptible to lipid peroxidation induced by oxidative stress. This study aimed to evaluate oxidative stress markers in the serum of patients with relapsing-remitting MS (RRMS) and examine their correlation with lipid markers.
Methods: A total of 18 MS patients (14 women and 4 men) and 18 healthy subjects (matched by age and sex) were enrolled in this cross-sectional study. The serum samples were collected in both relapsing and remitting phases. The prooxidant-antioxidant balance (PAB), malondialdehyde (MDA), and oxidized LDL (oxLDL) were measured as markers of oxidative stress.
Results: The mean age of participants was 29.21 (22-42) years. In the comparison between the patient and control groups, the most differences were increased levels of PAB in the patient group (P < 0.05), no difference between relapsing and remitting phases (P = 0.995), increased MDA levels in the relapsing phase (P = 0.013)––but no change in the remitting phase (P = 0.068), no difference in LDL and oxLDL levels in the patient group (P > 0.05), and MDA, LDL, and oxLDL levels did not have any significant correlation with PAB (P > 0.05).
Conclusion: High levels of oxidative stress markers were present in both phases of the disease. Lipid peroxidation markers (such as MDA) increased in the acute phase, but oxLDL did not change. Also, there was no significant correlation between oxidative stress and cholesterol markers.