SREBP.

Praeruptorin B inhibits the SREBPs activity and decreases intracellular lipid levels. Praeruptorin B is found to powerfully decrease the SRE-luciferase activity, and this effect is dose dependent. Praeruptorin B shows negligible cytotoxicity, even at the higher concentration. Praeruptorin B also significantlytly down-regulates the expression of SREBP-1c and SREBP-2 . Praeruptorin B also exhibits significant inhibition on the activity of UGT1A9.

The mice treated with Praeruptorin B (50 mg/kg) are significantly lighter than the vehicle treated mice, although they are still heavier than the chow diet-fed mice, suggesting that Praeruptorin B can ameliorate diet-induced obesity (DIO). More importantly, the fat/lean and fat/body-weight ratios are obviously dropped at the same dosage of Praeruptorin B treated mice. It is also showed that the serum TC and TG levels of Praeruptorin B treated mice are significantly lower than those of the HFD-fed mice. Praeruptorin B increases HDL-c and decreases LDL-c similar as lovastatin. In addition, compared with vehicle treated mice, Praeruptorin B significantly lowers the level of TC and TG in liver, comparable to lovastatin. The staining results reveal that Praeruptorin B-treated mice exhibit less lipid accumulation than that of vehicle treated mice. The elevated fasting blood glucose and insulin in HFD-fed mice are significantly reduced by Praeruptorin B.