thiobarbituric-acid and Breast-Neoplasms

The purpose of this study is to evaluate the level of oxidative stress before and after breast cancer surgery.. Malondialdehyde (MDA) level was tested using a thiobarbituric acid (TBA) assay based on the release of a color complex due to TBA reaction with MDA. The glutathione S-transferase (GST) activity was evaluated by enzymatic conjugation of reduced glutathione (GSH) with 1-chloro-2,4-dinitrobenzene. The level of total glutathione (reduced GSH and oxidized GSSG) was detected using a recycling system by 5,5-dithiobis(2-nitrobenzoic acid). The levels of the indices were determined in the serum of 52 patients before surgery, two hours and five days after surgery, and in 42 healthy women.. In the patients over 50 years old the level of MDA was higher after surgery in comparison with before surgery, and GST activity was lower in comparison with the control. The GSH + GSSG level in both ages groups after surgery was lower than in the control. Significant differences of MDA level were detected in patients with stage III after surgery compared to the control. The level of GSH + GSSG was significantly lower in the patients with I-III stages compared to the control.. The most expressed changes demonstrate the significance of MDA as a marker to evaluate oxidative stress in breast cancer patients. The degree of oxidative stress depends on the patient's age and stage of disease.

Topics: Adult; Antioxidants; Breast Neoplasms; Female; Glutathione Transferase; Humans; Malondialdehyde; Middle Aged; Oxidants; Oxidative Stress; Postoperative Period; Preoperative Period; Thiobarbiturates

Vitamin C is a water-soluble chain-breaking antioxidant that has beneficial effects on lipid-metabolizing enzymes. In the present study, the level of thiobarbituric acid (TBA) substances and antioxidant enzymes such as catalase, superoxide dismutase (SOD), glutathione peroxidase and glutathione-S-transferase were assayed.. The level of TBA substances and antioxidant enzymes was determined in plasma and RBC hemolysates, respectively, in 60 postmenopausal women with breast cancer.. The data obtained from the study revealed that the levels of TBA and the antioxidant enzymes catalase, SOD, glutathine peroxidase and glutathine-S-transferse were significantly normalized by vitamin C treatment in the RBC hemolysate.. The results compared vitamin C-treated breast cancer patients with normal individuals and showed that co-administration of vitamin C is more beneficial in breast cancer patients treated with tamoxifen.

Topics: Antineoplastic Agents, Hormonal; Antioxidants; Ascorbic Acid; Breast Neoplasms; Catalase; Erythrocytes; Female; Glutathione; Glutathione Peroxidase; Glutathione Transferase; Humans; Lipid Peroxidation; Oxidative Stress; Superoxide Dismutase; Tamoxifen; Thiobarbiturates; Vitamin E; Vitamins

Female athymic nude mice were implanted subcutaneously with human breast carcinoma MDA-MB231. Seven to ten days later, the mice were divided into groups and fed a purified diet containing the following types of fat (% of diet): (i) 20% corn oil (CO); (ii) 15% CO:5% fish (menhaden) oil (FO); (iii) 10% CO:10% FO; (iv) 5% CO:15% FO; (v) 1% CO:19% FO; and (vi) 1% CO:19% FO plus antioxidants (alpha-tocopherol acetate, 2000 IU/kg diet and tertiary butyl-hydroquinone, 2% of total fat). The linoleic acid levels (% of diet) of the groups were 12.0, 9.1, 6.2, 3.3, 0.9 and 0.9%, respectively. After 6-8 wk, the carcinomas were assessed for tumor volume (cm3) and assayed for thiobarbituric acid reactive substances (TBARS). Human breast carcinoma growth was suppressed in mice consuming FO diets without antioxidants as compared to mice fed CO; the greater the amount of dietary FO fed, the greater the carcinoma growth suppression (P < 0.05). The addition of antioxidants to the FO diet significantly (P < 0.05) reversed the FO-induced carcinoma growth suppression. Concentrations of TBARS in the human breast carcinomas were increased in all the FO (without antioxidants) fed mice, compared to mice fed CO; the level of increase in TBARS was directly related to the increase in the level of FO fed (P < 0.05). The addition of antioxidants to the FO diet significantly (P < 0.05) reduced the concentration of TBARS in the breast carcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Breast Neoplasms; Dietary Fats; Female; Fish Oils; Humans; Lipid Peroxidation; Mice; Mice, Nude; Neoplasm Transplantation; Thiobarbiturates

To clarify the mechanism by which gammalinolenic acid (GLA) is more tumoricidal than docosahexaenoic acid (DHA), we have compared the incorporation of the respective exogenously added ethyl esters GLAe and DHAe into the phospholipids of tumorigenic ZR-75-1 and non-tumorigenic CV-1 cells relative to the ability of the cells to survive and to accumulate thiobarbituric acid reactive substances (TBARS). GLA and DHA were incorporated in the phospholipids to the same extent, but GLA disappeared more rapidly than DHA in both cell lines. GLAe induced about twice as much intracellular TBARS as DHAe in both cell lines, but killed ZR-75-1 cells four times more effectively than DHAe. DHAe induced 11-15 fmoles malondialdehyde-equivalents (MDA-eq)/cell in both ZR-75-1 and CV-1 cells, whereas GLAe induced 5-6 times more TBARS in ZR-75-1 cells (26-30 fmoles MDA-eq/cell) than in CV-1 cells (5-6 fmoles MDA-eq/cell). The results show that there is no difference in GLA and DHA incorporation into phospholipids, but that their metabolism differs in the two cell types. The data also suggest that the cytocidal potential is related to TBARS levels in a nonlinear fashion. The relationship between excess prostaglandin production and excessive cell death due to GLA is discussed.

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Cell Survival; Cells, Cultured; Docosahexaenoic Acids; Evaluation Studies as Topic; gamma-Linolenic Acid; Humans; Linolenic Acids; Malondialdehyde; Phospholipids; Thiobarbiturates; Tumor Cells, Cultured