How does Riccardin C (RC) affect cholesterol efflux in THP-1 cells?

Cholesterol efflux is a critical process in lipid homeostasis and is mediated by ATP-binding cassette transporters (ABC) A1 and G1. LXR activation is known to upregulate these transporters, enhancing cellular cholesterol efflux.

Riccardin C (RC) increases the expression of ABCA1 and ABCG1 mRNA in THP-1 cells, leading to enhanced cellular cholesterol efflux. Specifically, RC (30 µM) increased ABCA1 mRNA levels by 2-fold and ABCG1 mRNA levels by 2.6-fold. This increase in transporter expression resulted in a 2-fold elevation in cholesterol release from THP-1 cells, both in the presence and absence of exogenous apolipoprotein A-I. This suggests that RC can promote cholesterol efflux through the upregulation of key transporters involved in this process.