Vitamin A Research Today is a free monthly online journal that collates and summarizes the latest research about Vitamin A, including details on retinol, benefits, dosage, supplements, deficiency, information.

Vitamin A and beta-carotene inhibitory effect during 1,2-dimethylhydrazine induced hepatocarcinogenesis potentiated by 5-azacytidine.

Sampaio AR, Chagas CE, Ong TP, Moreno FS

Laboratory of Diet, Nutrition and Cancer, Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.

5-Azacytidine is being used for reactivation of tumor suppressor genes. However, its administration during DNA repair pontentiates hepatocarcinogenesis. We observed chemopreventive activities by vitamin A and beta-carotene during early hepatocarcinogenesis. Thus, in the present study we evaluated vitamin A and beta-carotene chemopreventive potential during early hepatocarcinogenesis potentiated by 5-azacytidine. Wistar rats received vitamin A (VAA group), beta-carotene (betaCA group) or corn oil (CO and COA groups). After three weeks of treatment, all animals were initiated with 1,2-dimethylhydrazine. Twelve hours later VAA, betaCA and COA groups received a single dose of 5-Azc. Hepatocytes were selected/promoted by 2-acetylaminofluorene and 70% partial hepatectomy. All animals were sacrificed six weeks after initiation. Compared to CO group (without 5-azacytidine), COA group presented higher (p<0.05) nodule multiplicity, larger (p<0.05) gamma-GT positive lesions that occupied a larger (p<0.05) area of liver section. Compared to COA group, VAA group presented decreased (p<0.05) nodule multiplicity while betaCA group tended to present smaller gamma-GT positive lesions and to decrease occupied liver section. These results reinforce vitamin A and beta-carotene chemopreventive potential. Considering that 5-azacytidine potentiates hepatocarcinogenesis, more studies are needed to elucidate the efficacy and safety of this drug for cancer control.

Published 12 February 2007 in Food Chem Toxicol, 45(4): 563-7.
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