Intra-peritoneal application of catechins and EGCG as in vivo inhibitors of ozone-induced oxidative stress.

Oxidative stress is considered as a prominent feature of many acute and chronic diseases as well as of the normal aging process. We examined the effects of intra-peritoneal administration of catechins and EGCG as in vivo inhibitors of oxidative stress induced by ozone administration in two groups of Wistar rats. The first group was treated by intra-peritoneal administration of catechins and EGCG after the administration of ozone and the second group was pretreated by intra-peritoneal administration of catechins and EGCG prior to ozone administration. We determined in blood the activity of the enzymes superoxide dismutase and glutathione peroxidase, total antioxidant capacity, levels of copper and zinc and in urine malonaldehyde contents. Ozone administration resulted in significant reduction of glutathione peroxidase activity, plasma zinc levels and plasma and Red Blood Cells antioxidant capacity. Catechins and EGCG upregulate superoxide dismutase activity and maintain plasma and Red Blood Cells antioxidant capacity. Malonaldehyde levels at the end of the study were significantly increased only in the first group. Our data demonstrate that treatment with catechins and EGCG cannot reverse or prevent the effects of oxidative stress although some modulation occurs.

Selenium in serum and neoplastic tissue in breast cancer: correlation with CEA.

Trace element selenium (Se) is regarded to be a breast cancer preventive factor involved in multiple protective pathways. In all, 80 women with breast cancer who underwent a radical mastectomy were enrolled in the study. Serum Se and carcinoembryonic antigen levels were measured using a fluorometric and IRMA assay, respectively. Se tissue concentration was determined by a tissue extracting fluorometric assay. For statistical analysis purposes t-test was used and P-values <0.001 were regarded as statistically significant. Serum Se was 42.5+/-7.5 microg l(-1) in breast cancer patients and 67.6+/-5.36 microg l(-1) in the age-matched control group of healthy individuals. Serum carcinoembryonic antigen in patients was 10+/-1.7 U ml(-1) (normal <2.5 U ml(-1) in nonsmokers/<3.5 U ml(-1) in smokers). A statistically significant difference was found for both serum Se and CEA between two groups studied (P<0.001). Neoplastic tissue Se concentration was 2,660+/-210 mg g(-1) tissue; its concentration in the adjacent non-neoplastic tissue was 680+/-110 mg g(-1) tissue (P<0.001). An inverse relationship between Se and CEA serum levels was found in the two groups studied (r=-0.794). There was no correlation between serum/tissue Se concentration and stage of the disease. The decrease in serum Se concentration as well as its increased concentration in the neoplastic breast tissue is of great significance. These alterations may reflect part of the defence mechanisms against the carcinogenetic process.

Ascorbic acid (vitamin C) effects on withdrawal syndrome of heroin abusers.

BACKGROUND: Ascorbic acid (vitamin C), administered orally in high doses has been observed to relieve pain and reduce opioid use in cancer patients. In vitro studies have also shown that antioxidants, such as vitamin C, may, at high concentrations, inhibit the endogenous opioid degrading metalloenzyme and increase endorphin levels. In the present study the effects of oral administration of high doses of vitamin C on withdrawal syndrome of heroin abusers were investigated. MATERIALS AND PATIENTS: Ascorbic acid at doses of 300 mg/kg b.w/day, supplemented with vitamin E (5 mg/kg b.w/day), was orally administered in two groups of heroin addict subjects consisting of in-patients (Group A, 30 males) and one of out-patients(Group B, 10 males), for a minimum of 4 weeks. The group A in-patients were also administered the conventional (diazepam + analgesic) medication. The results on the intensity of withdrawal syndrome (WS), estimated according to DMS-III criteria, were compared to a third group of heroin addict in-patients (group C, 30 males-control group), treated only by conventional medication. RESULTS: The patients of the vitamin C-treated groups (in-patients and out-patients) experienced mild WS (in 46.6% to 50% of the subjects) in contrast to the control group patients, who experienced mild WS in 6.6% of the cases. The vitamin C-treated subjects expressed major WS ranging from 10% to 16.6%, in contrast to the untreated subjects (control group), who expressed a major WS in 56.6% of the cases. CONCLUSIONS: The results indicate that high doses of ascorbic acid administered orally, may ameliorate the withdrawal syndrome of heroin addicts. Further studies are needed in order to estimate the dose- and time-dependent effects of ascorbic acid treatment, and to clarify its mechanisms of action in the withdrawal syndrome.