RESUMO
BACKGROUND AND AIMS: Previously, we reported that granulocyte-colony stimulating factor (G-CSF) improves hepatic steatosis in experimental animals. It may also have preventive effects on the development of hepatic steatosis. Therefore, we investigated the preventive effects of G-CSF by using a high-fat diet (HFD) rat model. MATERIALS AND METHODS: Twelve rats were fed HFD and 6 rats were fed control diet from 10 weeks of age. Once little steatosis was confirmed in the liver (after 10 weeks of feeding the HFD; at 20 weeks of age), HFD rats were randomly divided into two groups and treated with either G-CSF (100 µg kg-1 day-1 for 5 consecutive days every other week; HFD/G-CSF rats) or saline (HFD/saline rats) for 10 weeks at 20 weeks of age. All rats were sacrificed at 30 weeks of age. Histology was examined by hematoxylin and eosin (H-E) and Oil Red O staining, and the expression levels of genes of associated with lipogenesis and ß-oxidation enzymes were determined by qRT-PCR. RESULTS: Histological examinations revealed that HFD/G-CSF rats had significantly lower lipid accumulation in their hepatocytes than did HFD/saline rats (p < 0.05). HFD/G-CSF rats also showed lower expression levels of genes associated with lipogenesis and higher expression levels of genes associated with ß-oxidation than HFD/saline rats (p < 0.05). CONCLUSION: In conclusion, we found that G-CSF prevented development of hepatic steatosis in an HFD rat model. The preventive effect may be associated with the regulation of gene expression involved in hepatic lipogenesis and ß-oxidation.