Téma: XXVIII. Základní a aplikovaný výzkum v onkologii
Číslo abstraktu: 291
Autoři: RNDr. Bianka Bojková, Ph.D.; doc. MUDr. Karol Kajo, Ph.D.; RNDr. Peter Orendáš, Ph.D.; RNDr. Terézia Kisková, Ph.D.; RNDr. Vlasta Demečková, Ph.D.; doc.RNDr. Monika Kassayová, CSc.; doc. RNDr. Peter Kubatka; Doc. MUDr. Martin Péč, Ph.D.
Chemoprevention remains one of the best ways to decrease cancer incidence. Preclinical studies showed oncostatic properties of peroral antidiabetics from thiazolidinedione (glitazone) group in various cancer models including mammary cancer. Melatonin, the major hormone produced by the pineal gland, displays pleiotropic properties including antiproliferative, antiinfl ammatory, antiangiogenic, and immunomodulative effects. Preventive and therapeutic properties of melatonin were proved in many types of neoplasms in vivo, positive effects were reported in human cancer too. This study evaluated effects of pioglitazone and melatonin administered alone and in combination in chemically-induced mammary carcinogenesis in rats fed a high-fat diet.
Materials and methods:
Female Sprague-Dawley rats aged 30 days were used in the experiment. Mammary carcinogenesis was induced by N-methyl-N-nitrosourea (50 mg/ kg b.w.) administered intraperitoneally on 41st postnatal day. Pioglitazone was administered in a diet (10% fat) at a concentration of 100 ppm. Melatonin was administered in a drinking water at a concentration of 20 mg/l. Both pioglitazone and melatonin were administered for the whole length of the experiment. The animals were weighed and palpated weekly for the presence of mammary tumors and the food and water intake were monitored. The experiment was terminated 16 weeks after the carcinogen administration, basic tumor growth parameters and selected hematologic and metabolic variables were evaluated.
No significant changes of tumor growth parameters were recorded. Hematologic variables showed only minor changes. Glycemia did not exceed normal values in any experimental group, pioglitazone administration, both alone and in combination, increased cholesterolemia. Pioglitazone decreased phospholipid concentration and in combination with melatonin increased cholesterol concentration in liver. Melatonin enhanced lipid peroxidation in liver, the combination of pioglitazone and melatonin had the same effect both in liver and thymus.
Pioglitazone and melatonin did not have a significant eff ect on progression of chemically-induced mammary tumors and induced some adverse lipid metabolism eff ects in rats fed a high-fat diet.
This work was supported by VEGA Grant Science Agency, Ministry of Education, Slovak Republic, project No. 1/ 0153/ 13.
Datum přednesení příspěvku: 25. 4. 2014