Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in the recent decades in both developed and developing countries, and is predicted to be the major etiology for liver transplantation in the next decade. Thus, pharmacological strategies to treat NAFLD are urgently needed. Natural products are considered an excellent source for drug discovery. By utilizing an image-based high-throughput screening with a library containing 3000 Taiwanese indigenous plant extracts, we discovered that the extract of Syzygium simile leaves (SSLE) has an anti-lipid droplet (LD) accumulation effect in hepatic cell lines. Analyses of the expression profile of genes involved in lipid metabolism revealed that SSLE suppressed the mRNA expression of CD36, fatty acid translocase. In agreement with this observation, we showed that SSLE inhibited CD36 protein expression and fatty acid uptake and has only limited effects on pre-formed LDs. Moreover, SSLE reduced LD accumulation and CD36 expression in enterocyte and macrophage cell lines. In conclusion, our findings suggest that SSLE could serve as a potential source for the discovery of novel therapeutic modalities for NAFLD and that the suppression of CD36 expression and fatty acid uptake could contribute to the lipid-lowering effect of SSLE.
Keywords: high-content screening; lipid droplet; metabolic diseases; natural products; non-alcoholic fatty liver disease.