Potential Transmembrane Proteins-transporters of Chelidonic Acid for its Intracellular Uptake: In Silico Simulation

Small molecules are biologically active organic compounds with molecular weight below 1 kDa. Their small size enables efficient transport across cell membranes and modulation of intracellular signaling, making them promising for drug development. Chelidonic acid (ChA) is a small molecule (184 Da) with a wide range of biological effects, but its transport mechanisms and molecular targets remain unknown.

The aim of this study is to identify a possibility of ChA uptake by human cells and to search for transporter proteins that may be involved in the intracellular trafficking of ChA using a combination of in silico and in vitro approaches.

Co-culturing of human MCF-7 cells with ChA was conducted in vitro for 4 h and residual (not absorbed by cells) ChA concentration in solution was measured using HPLC. Candidate transporters were screened from databases. Molecular docking was performed with Autodock Vina, and molecular dynamics simulations were run for 50 ns using GROMACS to assess protein-ligand interactions. Statistical analysis used the R language with Newey-West estimator and Welch's t-test. HOLE and VMD were used for 3D-reconstruction and visualization of transport channels.

MCF-7 cancer cells uptake ChA through one or several of the common cell transport proteins. Initial screening identified six transmembrane proteins, with further analysis pinpointing three candidates (GLUT3, SVCT1, URAT1) demonstrating structural and functional compatibility for ChA transport.

The study contributes to the understanding of the pharmacokinetics and pharmacodynamics of ChA and provides the basis for the rational design of pharmaceutical substances based on it.