Abstract:

The aim of the present study was to observe the effect of Cf-LCB on the proliferation and differentiation of
3T3-L1 preadipocytes and to investigate the possible underlying mechanism. The effect of Cf-LCB on the proliferation
of 3T3-L1 preadipocytes was evaluated by MTT assay. After using differentiation cocktail to differentiate 3T3-L1
preadipocytes, the effect of Cf-LCB on the differentiation of 3T3-L1 preadipocytes was evaluated by oil red O-staining
and determining TG content. mRNA expression levels of key genes associated with differentiation and WNT/β-catenin
signal pathway in 3T3-L1 preadipocytes were measured by qRT-PCR. Expression levels of key proteins in WNT/β-catenin
signal pathway were measured by Western blotting. Results showed that Cf-LCB significantly inhibited the proliferation of
3T3-L1 preadipocytes, prevented the formation of lipid droplets in mature 3T3-L1 adipocytes and down-regulated C/EBPα
and PPARγ. The mRNA expression of FZ1, LRP6 and β-catenin was distinctly enhanced by Cf-LCB, suggesting activation
of WNT/β-catenin pathway. The increased protein expressions of key factors in WNT/β-catenin pathway including LRP6,
total and nuclear β-catenin further demonstrated that Cf-LCB could markedly suppress the proliferation and differentiation of
3T3-L1 preadipocytes by activating WNT/β-catenin pathway.

Key words: Cucumaria frondosa, long-chain base, 3T3-L1 preadipocytes, adipogenesis, WNT/β-catenin signal pathway