Influence of selenium on glutathione and some associated enzymes in rats with mammary tumor induced by 7,12-Dimethylbenz(a)anthracene

Abstract

A recent finding in epidemiological and laboratory studies suggests that the ratio of selenium to glutathione is lower in breast cancer subjects than its control counterparts. Selenium, an antioxidant and anticarcinogen, can modify the status of glutathione and some associated enzymes by blocking peroxidation of lipids in membranes of cancer subjects. Studies were conducted using female albino rats of Wistar strain bearing mammary tumor induced by 7,12-dimethylbenz(a) anthracene to assess the biological role of selenium on some antioxidant enzymes associated with the maintenance of glutathione status. For induction of mammary tumor, 25 mg DMBA in a 1 ml emulsion of sunflower oil and physiological saline was injected subcutaneously to each rat. One group in each of control and tumor bearing rats, were fed 5 mg sodium selenite/kg diet from the day of tumor induction for 24 weeks. Increase in the reduced glutathione concentration was preceded by significant increase in the oxidized glutathione as well as in the activities of gamma-glutamylcysteine synthetase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, and glucose-6-phosphate dehydrogenase by selenium administration in rats bearing tumor. However, selenium administration to rats bearing tumor decreased the activity of gamma-glutamyl transpeptidase. These observations clearly demonstrate the influence of dietary selenium supplementation in correcting abnormal changes in glutathione turnover and some associated enzymes in tumor induced rats.

Aryl hydrocarbon receptor/cytochrome P450 1A1 pathway mediates breast cancer stem cells expansion through PTEN inhibition and β-Catenin and Akt activation

“…TCDD is classified as a known human carcinogen and potent tumor promoter, whereas, DMBA is a powerful organ-specific laboratory carcinogen and tumor initiator that is widely used as a chemical carcinogen in rat mammary tumor model [46, 47]. The carcinogenicity and tumoreginicity of TCDD and DMBA are attributed to the ability to induce CYP1A1 and CYP1B1.…”

Chemopreventive efficacy and anti‐lipid peroxidative potential of Jasminum grandiflorum Linn. on 7,12‐dimethylbenz(a)anthracene‐induced rat mammary carcinogenesis

“…A single dose of 25 mg DMBA in 1 mL sunflower oil subcutaneously to female albino Wistar rats induced the formation of tumors by 12 weeks [14]. We have also Values are expressed as mean ± SD (n ¼ 6).…”

“…Rats in groups 1 and 2 were induced mammary carcinogenesis by providing single subcutaneous injection of 25 mg DMBA in 1 mL emulsion of sunflower oil and physiological saline to each rat [14]. Rats in groups 1 and 2 were induced mammary carcinogenesis by providing single subcutaneous injection of 25 mg DMBA in 1 mL emulsion of sunflower oil and physiological saline to each rat [14].…”

Dose response chemopreventive potential of allyl isothiocyanate against 7,12-dimethylbenz(a)anthracene induced mammary carcinogenesis in female Sprague-Dawley rats

“…Mammary carcinogenesis was induced in Sprague-Dawley rat using a single subcutaneous injection of 25 mg of DMBA in 1 mL emulsion of sunflower oil (0.75 mL) and physiological saline (0.25 mL) to each rat [21].…”