3T3-L1 세포에서 Adipogenesis 억제를 통한 Kaki-tannin의 항비만 활성

Persimmon (Diospyros kaki Thunb.) is widely cultivated in Asian countries such as Korea, China, and Japan. Although its various beneficial functions have been well-documented, its anti-obese effect is relatively unknown. Here, we prepared kaki-tannins from unripe astringent Daebong persimmon (DU), red-ripe non-astringent Daebong persimmon (DR), unripe astringent Cheongdo flat shaped persimmon (CU), red-ripe non-astringent Cheongdo flat shaped persimmon (CR), and unripe non-astringent Fuyu persimmon (FU). Cytotoxicity of the kaki-tannins were evaluated by MTT assay in 3T3-L1 cells. The treatment up to 100 μg/mL of all kaki-tannins for 24 h did not affect to the 3T3-L1 cell viability. Thus, the concentration up to 100 μg/mL of the kaki-tannins were chosen for subsequent experiments. The treatment with 100 μg/mL of kaki-tannins prepared from DR and CU significantly inhibited lipid accumulation of 3T3-L1 adipocytes. In line with this result, the decreased number and size of intracellular lipid droplets in 3T3-L1 adipocytes treated with DR and CU kaki-tannins were observed. The 3T3-L1 cells treated with DR and CU kaki-tannins showed down-regulated mRNA expression levels of C/EBPα and FAS as judged by RT-PCR. Our study also revealed that DR and CU kaki-tannins-inhibited adipogenesis are strongly limited in the early stage of 3T3-L1 adipogenesis. These evidences suggest that kaki-tannin has the potential as anti-obese natural materials, and different function and role of kaki-tannins in anti-adipogenic activities may be mediated to persimmon types and maturation stage.