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영남의대학술지 Vol.24_No.2 Suppl. P.S493-504, Dec. 2007

Original Article

포화지방산과 불포화지방산이 배양 지방세포의 비만유전자와 지방산합성효소유전자 발현에 미치는 영향

Effect of Saturated and Unsaturated Fatty Acid on Ob Gene and Fatty Acid Synthase Gene Expression in 3T3-L1 Adipocyte

지정규, 박소영, 김종연, 김희선*, 김용운

영남대학교 의과대학 생리학교실, 미생물학교실*

책임저자：김용운, 대구광역시 남구 대명5동 317-1, 영남대학교 의과대학 생리학교실

Tel: (053) 620-4333, Fax: (053) 651-3651

Email: ywkim@med.yu.ac.kr

December 30, 2007

Abstract

Purpose：The ob gene, specifically expressed in adipocyte, encodes leptin, a hormone that induces satiety and increases energy expenditure. In this study, effects of saturated fatty acid and polyunsaturated fatty acid on ob gene expression were investigated by quantitative competitive RT-PCR in a mouse cell line (3T3-L1) which can be induced to differentiate into adipocytes. In addition to ob gene, expression of the fatty acid synthase gene as a marker of lipogenesis was measured simultaneously.
Materials and Methods：The 3T3-L1 fibroblast cell were cultured in the Dulbecco’s modified Eagle medium with 10% fetal bovine serum. The differentiation of 3T3-L1 fibroblast to adipocyte was induced by the treatment of 250 nM dexamethasone and 0.5mM 1-methyl-3 -isobutylxanthine. At 10～14 days after induction, 3T3-L1 cells were fully differentiated and had had lipid droplets in the cytoplasm. At that time, 3T3-L1 adipocytes were cultured for 12 hours in the fatty acids contained medium and were harvested for RNA extraction. Palmitate as a saturated fatty acid and docosahexaenoic acid (DHA) as a polyunsaturated fatty acid were used in this experiment and treated concentration was 600 μMol.
Results：After conversion to adipocytes, glycerol-3 phosphate dehydrogenase activity was increased and leptin mRNA was expressed. Ob gene expressions of differentiated adipocytes were suppressed by palmitate treatment, however, there was no significant change in DHA treated adipocyte. Fatty acid synthase gene expressions, on the other hand, were suppressed by DHA treatment and not changed by palmitate treatment.
Conclusion：These results suggested that polyunsaturated fatty acid inhibited lipogenic process and saturated fatty acid inhibited lipolytic process at cultured adipose cell level.

Key Words: 3T3-L1 adipocytes, Docosahexaenoic acid, Palmitate, Ob gene

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