Chemical Constituents with Anti-Lipid Droplet Accumulation and Anti-Inflammatory Activity from Elaeagnus glabra .

Non-alcoholic fatty liver disease (NAFLD) is a type of steatosis caused by excess lipids accumulating in the liver. The prevalence of NAFLD has increased annually due to modern lifestyles and a lack of adequate medical treatment. Thus, we were motivated to investigate the bioactive components of Formosan plants that could attenuate lipid droplet (LD) accumulation. In a series of screenings of 3000 methanolic extracts from the Formosan plant extract bank for anti-LD accumulation activity, the methanolic extract of aerial parts of Elaeagnus glabra Thunb. showed excellent anti-LD accumulation activity. E. glabra is an evergreen shrub on which only a few phytochemical and biological studies have been conducted. Here, one new flavonoid ( 1 ), two new triterpenoids ( 2 and 3 ), and 35 known compounds ( 4 - 38 ) were isolated from the ethyl acetate layer of aerial parts of E. glabra via a bioassay-guided fractionation process. Their structures were characterized by 1D and 2D NMR, UV, IR, and MS data. Among the isolated compounds, methyl pheophorbide a ( 37 ) efficiently reduced the normalized LD content to 0.3% with a concentration of 20 μM in AML12 cell lines without significant cytotoxic effects. 3- O -( E )-Caffeoyloleanolic acid ( 13 ) and methyl pheophorbide a ( 37 ) showed inhibitory effects on superoxide anion generation or elastase release in fMLP/CB-treated human neutrophils (IC 50 < 3.0 μM); they displayed effects similar to those of the positive control, namely, LY294002. These findings indicate that E. glabra can be used for developing a new botanical drug for managing LD accumulation and against inflammation-related diseases.