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PLASMA MALONDIALDEHYDE (MDA) LEVELS IN BREAST AND LUNG CANCER PATIENTS

Objective: To measure the levels of malondialdehyde (MDA), a marker of lipid peroxidation, in patients with breast and lung cancer.

Lipid peroxidation and antioxidant status in blood and tissue of malignant breast tumor and benign breast disease

Changes in the levels of malondialdehyde (MDA), nitrate and nitrite (as an index of nitric oxide production), lipid hydroperoxide (LOH), total antioxidant capacity (TAC), lipids (total cholesterol and triglycerides) and lipoproteins (HDL‐ and LDL‐cholesterol) were estimated in breast cancer patients (n = 15) and benign breast disease (n = 15). Serum and tissue MDA levels were found to be decreased in breast cancer patients compared to the benign group (p < 0.05). In contrast, nitrate and nitrite levels were increased in serum and tissue of the cancer group compared to benign breast disease patients (p < 0.05). Compared to the benign group, tissue TAC levels were elevated in the breast cancer patient group (p < 0.05). Total cholesterol and HDL‐cholesterol were elevated in the benign group compared with cancer patients (p < 0.05). These findings support the hypothesis that lipid peroxidation in serum and tissue of benign breast disease is greater than in breast cancer. However, the enhanced levels of nitric oxide may be in response to inflammation in patients with breast cancer. Total antioxidant status is lower in benign tissue than in cancerous tissue, probably to compensate for this elevated free radical production.

Serum Cardiac Markers in Patients with Acute Myocardial Infarction: Oxidative Stress, C-Reactive Protein and N-Terminal Probrain Natriuretic Peptide

The aim of this study was to investigate the predictive value of an oxidative stress, C-reactive protein (CRP) and N-terminal probrain natriuretic peptide (NT-proBNP) biomarkers in acute myocardial infarction (AMI). The study population contained 100 patients with AMI and 40 healthy subjects. Malondialdehyde (MDA) was measured as thiobarbituric acid reactive substances. Total antioxidant status (TAC) was assayed with colorimetric method. CRP and NT-proBNP was quantitated by immunoassay. MDA, CRP and NT-proBNP levels were found significantly high in patients with AMI as compared to healthy controls (p<0.01). Patients were divided into six groups based on the presence of disease history before AMI. In patients with non-disease before AMI. MDA, CRP and NT-proBNP levels were lowest among the patient groups. MDA levels in patients with hyperlipidemia/ diabetes/renal disease were higher than the other groups. TAC levels in patients with hypertension were lower than as compared to healthy controls (p<0.05). CRP levels in hypertension + hyperlipidemia patients and NT-proBNP levels in cardiovascular + hypertension patients were found high as compared to other patient groups. It is concluded that serum levels of MDA, CRP and NT-proBNP were significantly increased in patients with AMI and these markers were strongly predictive in AMI.

Serum β–carotene, vitamin E, vitamin C and malondialdehyde levels in several types of cancer

We measured the levels of serum carotenoids (β–carotene), total tocopherol (vitamin E), ascorbic acid and malondialdehyde (MDA) in newly diagnosed cancer cases. Levels of the antioxidants and MDA in serum samples from 208 subjects with cancer affecting different sites (59 breast, 38 head and neck, 46 genitourinary, 12 lung, 20 gastrointestinal and 33 other sites) were compared with levels in 156 controls. Cases and controls were compared with respect to a number of potentially confounding factors: age, sex, smoking status, Quetelet index (kg/m2), diet and alcohol intake. Mean (±SD) levels of β–carotene, vitamin E and vitamin C were significantly lower among the cases than the controls (49 35±36 55 μg/1, 0 60±014 mg/dl, 0 40±0 27 mg/dl and 75 31±28 59 mg/dl, 0 98±0 13 mg/dl, 0 88±0 47 mg/dl, respectively) (P < 0 05).

Oxidative stress in patients with essential hypertension: A comparison of dippers and non-dippers

BACKGROUND Oxidative stress seems to play an important role in the pathophysiology of essential hypertension. We aimed to examine serum MDA, NO, 8-OHdG, ADMA, NT, CoQ10 and TAC as biomarkers of oxidative stress in dipper and non-dipper hypertensive patients. METHODS Eighteen dipper hypertensives, 20 non-dipper hypertensives and 22 healthy control subjects were included in the study. Clinical assessment and ambulatory blood pressure monitoring were performed in patients. Serum MDA, TAC and NO levels were measured by using spectrophotometric methods. CoQ10 levels were measured by HPLC method. 8-OHdG, ADMA and NT were quantitated by ELISA methods. RESULTS MDA levels were significantly higher in dipper and non-dipper groups compared to controls (p<0.05 and p<0.01, respectively). TAC levels were found at low level in patients dipper and non-dipper patients compared to control group (p<0.01). Higher ADMA and NT levels but lower CoQ10 levels were found in non-dipper group compared to healthy controls (p<0.01, p<0.05, and p<0.05, respectively). ADMA levels were found higher in non-dipper group than those of dipper group (p<0.01). DISCUSSION Increased ADMA, NT levels and decreased CoQ10 levels in non-dipper hypertensive patients might indicate more severe oxidative stres compared with dipper hypertensive patients, which plays an important role in the development of cardiovascular diseases. Increased MDA and reduced TAC levels might be considered as prospective prognostic markers of the development of cardiovascular diseases in dipper and non-dipper hypertensive patients.

Increased oxidative DNA damage and impaired antioxidant defense system in patients with gastrointestinal cancer

BACKGROUND Highly active intermediates are formed in aerobic metabolism which in turn leads to cellular damage. It is increasingly proposed that free radicals play a key role in human cancer development. The aim of this study was to investigate changes in 8-hydroxy-deoxyguanosine, nitrite+nitrate, total glutathione, total antioxidant capacity levels and superoxide dismutase, catalase, glutathione peroxidase activities in operative patients with gastrointestinal cancer before and after surgery and compare with inoperative patients. METHODS Oxidative stress parameters were measured in 59 gastrointestinal cancer patients and 20 controls. 8-hydroxy-deoxyguanosine was quantitated by Elisa method. Superoxide dismutase, catalase, glutathione peroxidase were assayed with colorimetric methods; Nitrite+nitrate, total glutathione and total antioxidant capacity were assayed with spectrophotometric methods. RESULTS 8-hydroxy-deoxyguanosine levels in cancer patients were higher than those of control group (p<0.01). Similarly, glutathione levels were increased compared with controls (p<0.01). However, nitrite+nitrate, total antioxidant capacity levels and superoxide dismutase and catalase activities were decreased in cancer patients compared with controls (p<0.01, p<0.01, p<0.05, p<0.01, respectively). The patients were divided into two groups; operative (n = 30) and inoperative (n = 29). A significant difference was found in inoperative group compared with postoperative group according to glutathione peroxidase activity (p<0.05). DISCUSSION Our results demonstrate that the oxidant/antioxidant balance was altered in favor of free radicals and DNA damage in gastrointestinal cancer patients. Significant increases in 8-hydroxy-deoxyguanosine, glutathione and decreases in nitrite+nitrate, SOD, CAT activities and antioxidant molecules suggest the possible involvement of oxidative stress in gastrointestinal cancer. Glutathione peroxidase activities in postoperative patients were higher compared to inoperative patients.

Free radical reaction products and antioxidant capacity in beating heart coronary artery surgery compared to conventional bypass

Oxygen-derived free radicals are important agents of tissue injury during ischemia and reperfusion. The aim of this study was to investigate changes in protein and lipid oxidation and antioxidant status in beating heart coronary artery surgery and conventional bypass and to compare oxidative stress parameters between the two bypass methods. Serum lipid hydroperoxide, nitric oxide, protein carbonyl, nitrotyrosine, vitamin E, and β-carotene levels and total antioxidant capacity were measured in blood of 30 patients undergoing beating heart coronary artery surgery (OPCAB, off-pump coronary artery bypass grafting) and 12 patients undergoing conventional bypass (CABG, on-pump coronary artery bypass grafting). In the OPCAB group, nitric oxide and nitrotyrosine levels decreased after reperfusion. Similarly, β-carotene level and total antioxidant capacity also decreased after anesthesia and reperfusion. In the CABG group, nitric oxide and nitrotyrosine levels decreased after ischemia and reperfusion. However, protein carbonyl levels elevated after ischemia and reperfusion. Vitamin E, β-carotene, and total antioxidant capacity decreased after ischemia and reperfusion. Significantly decreased nitration and impaired antioxidant status were seen after reperfusion in both groups. Moreover, elevated protein carbonyls were found in the CABG group. The off-pump procedure is associated with lower degree of oxidative stress than on-pump coronary surgery.

Changes of sFas and sFasL, oxidative stress markers in serum and follicular fluid of patients undergoing IVF

PurposeThe Fas-Fas Ligand interaction is one of the essential events for the induction of apoptosis whereas the exact role of their soluble forms in the reproductive system is still not fully understood. Also oxidative stress in the pathogenesis of infertility causing diseases in women and has been suggested as one of the important factors that negatively affect IVF outcome. In this study, our aim was to evaluate serum and follicular fluid levels of soluble Fas soluble Fas Ligand, malondialdehyde, superoxide dismutase and total antioxidant capacity in patients undergoing IVF and compared with controls.MethodsThis study included 109 patients. Patients were classified as unexplained infertility (N = 31), PCOS (N = 19), tubal factor (N = 9) and endometriosis (N = 10) and compared with male factor infertility (N = 40) that was the control group. sFas and sFasL levels were measured by immunoassay method. MDA, SOD and TAC levels were measured by colorimetric method.ResultsPatients with unexplained infertility, PCOS and tubal factor had significantly lower sFas levels compared with their controls (respectively, p < 0.01, p < 0.05, p < 0.05). However, SOD activity in unexplained infertility, PCOS and endometriosisgroupswere significantly higher than control group (p < 0.01).Decreased follicular fluid TAC levels were found in all patient groups compared with controls (respectively, p < 0.01, p < 0.05, p < 0.01, p < 0.01).Patients with tubal factor had significantly higher serum sFasL (p < 0.05), but lower follicular fluid sFasL levels (p < 0.05) compared with unexplained infertility. Tubal factor and endometriosis groups had lowerfollicular fluid TAC levels compared to unexplained infertility and PCOSgroups (p < 0.01).Conclusion(s)In this study, serum and follicular fluid sFas levels were decreased and antioxidant activity was impaired in infertility, possibly implying increased apoptosis. Especially in unexplained infertility group changes in this parametres more remarkable.

The effect of 1-month thyme using in elite sportsmen on oxidant stress and anti-oxidant capacity

The object of the study is to determine the effect of thyme loading during exercise at elite wrestlers on oxidant stress and anti-oxidant capacity. Totally 18 elite wrestlers were involved in the study. The wrestlers were randomly divided into two groups, experimental and placebo. The subjects were loaded 1 g dried thyme tea three times a day after meals during 35-day period. The blood samples were taken before and after loading thyme, and total antioxidant capacity (TAC), melondialdehyde (MDA) and total sulphydryl group (RSH) were analysed. To evaluate the dates, Wilcoxon signed rank test was used for in-group evaluation and Mann–Whitney U test was used for inter group evaluation and significance level α was set at 0.05. While there were no differences between groups before loading thyme, TAC values were found meaningfully increased after loading in experimental group (p<0.05). However, the decrease in MDA values of the experimental group after loading thyme was statistically significant (p<0.01). The decreases in RSH values of the experimental group were insignificant (p>0.05). In the other hand experimental group decreasing of the MDA values and increasing of the TAC values were found statically significant compared with placebo groups (p<0.05). But compared with two groups RSH values were statically insignificant. It was concluded that thyme loading increases enzymatic antioxidant capacity but does not have any effects on non-enzymatic antioxidant structures during exercise. However, thyme loading reduced oxidant stress in elite sportsmen.

Assessment of Vitronectin, Soluble Epithelial-Cadherin and TGF-β1 as a Serum Biomarker with Predictive Value for Endometrial and Ovarian Cancers

Objectives: Extracellular matrix components, including vitronectin (VN), soluble epithelial-cadherin (sE-cadherin) and transforming growth factor-beta 1 (TGF-β1), play a key role in the invasion and metastasis of cancer. The objective of the study was to determine the clinical significance of serum levels of these molecules in patients with endometrial and ovarian cancers. Materials and Methods: Serum levels of VN, sE-cadherin and TGF-β1 in patients with endometrial (n=28) and ovarian cancers (n=40) and healthy controls (n=41) were measured by ELISA using commercial kits. Results: A significant difference was found in VN, sE-cadherin and TGF-β1 levels between patients and healthy controls (p<0.01, p<0.01 and p<0.05, respectively). Serum VN and sE-cadherin levels were decreased significantly in both endometrial and ovarian cancer patients compared to controls (p<0.01, p<0.01, respectively). Conversely, TGF-β1 levels were increased significantly in patients with ovarian cancer as compared to controls (p<0.01). There was no significant difference between healthy controls and endometrial cancer patients. Conclusion: In conclusion, our study reveals that serum VN, sE-cadherin and TGF-β1 levels can be candidate targets for providing new diagnostic procedures in endometrial and ovarian cancers.