Obesity and Adipocyte ACAT Expression

Example 1

To examine the function of ACATs in obesity, the expression patterns of ACAT1 and ACAT2 genes, and their gene products during adipogenesis of murine 3T3-L1 preadipocytes in vitro were examined. ACAT1 mRNA level was markedly increased in adipocytes from 2 days after initiation of adipogenesis (i.e., D2) as judged by real-time PCR assay (FIG. 1). However, ACAT2 mRNA level was similar between preadipocytes (D0) and mature adipocytes (D6) while a temporal reduction of ACAT2 level was observed at D2 (FIG. 1). In addition, white adipose tissue (WAT) isolated from high fat diet-induced obese mice displayed elevated mRNA level of ACAT1 and reduced mRNA level of ACAT2 when compared with those in lean mice as judged by real-time PCR assay. Leptin level was measured in WAT from lean and obese mice to ensure the development of obesity (FIG. 2). In addition, brown adipose tissue (BAT) from obese mice exhibited elevated levels of both ACAT1 and ACAT2. Uncoupling protein-1 (UCP-1) level was measured in BAT from lean and obese mice as a BAT-specific marker protein (FIG. 2). However, liver from lean and obese mice exhibited similar levels of ACAT1 and ACAT2 (FIG. 2).