Anti-obesity effects of escins extracted from the seeds of Aesculus turbinata BLUME (Hippocastanaceae)

To investigate the anti-obesity effects of escins extracted from the seeds of Aesculus turbinata BLUME, anti-obesity models in vitro and in vivo were employed. In a preliminary experiment, different solvent fractions of Aesculus turbinata BlUME as well as two isolated compounds were tested for their effects on pancreatic lipase (PL) in vitro. Subsequently, female ICR mice were fed a high fat diet with or without different concentrations of total escins for 11 weeks to examine body weight, parametrial adipose tissue weight, and hepatic triacylglycerol (TG) and total cholesterol (TC) contents. Plasma triacylglycerol levels (TG) after oral administration of lipid emulsions to rats were also investigated. The results showed that total escins (1 mg/ml) as well as two compounds isolated from total escins, namely escin Ib and IIa, showed inhibitory effects on PL activity. In vivo, total escins suppressed the increase in body weight, parametrial adipose tissue weight, TG content, and TC content in mice's liver; TG content in rat plasma was also reduced at 1, 2 and 3 h after oral administration of the lipid emulsion plus different concentrations of escins compared to those in the lipid emulsion groups. Meanwhile, mice fed a high fat diet plus 2% total escins for 3 d had an increased TG level in the feces compared to the HF group. The reason for this may be due to a delay in the intestinal absorption of dietary fat by inhibiting PL activity.