Scallop shell extract inhibits 3T3-L1 preadipocyte differentiation

In a previous study, we examined the in vitro and in vivo effects of organic components isolated from scallop shells (scallop shell extract) and found that rats fed with powdered scallop shell showed a reduction in white adipose tissue weight compared to rats fed a control diet. To clarify the mechanism of action, we have investigated the effects of scallop shell extract on the differentiation of 3T3-L1 preadipocyte cells. Scallop shell extract reduced lipid accumulation in 3T3-L1 cells during differentiation in a dose-dependent manner. Glycerol-3-phosphate dehydrogenase activity also decreased following treatment with scallop shell extract, suggesting that the extract inhibits adipocyte differentiation. In addition, scallop shell extract suppressed the expression of adipogenic transcription factors (peroxisome proliferator-activated receptor γ and CCAAT/enhancer binding protein-α) and inhibited differentiation-associated mitotic clonal expansion. These results support the possibility that scallop shell extract may work as an anti-obesity agent via the inhibition of adipocyte differentiation.