Predicting L-carnitine potential as LDH-inhibitor through In Silico approach

Abstract

Background: L-carnitine (LC) is suggested to inhibit lactate accumulation post-exercise. However, the exact mechanism of how LC inhibits lactate accumulation is still elusive. Lactate dehydrogenase (LDH) is a key enzyme that catalyzes the interconversion of pyruvate and lactate. Thus, the present study aimed to investigate the effect of LC in inhibiting LDH through in silico approach. Methods: The methods used in this study consisted of protein and ligand data collection, pharmacokinetic analysis, molecular docking, and molecular dynamics. The ligands used in this study are L-Carnitine and LDH-A inhibitor (AZ-33) as the control ligand, while the protein is human muscle LDH-A. Results: The results of this study indicate that L-carnitine has the potential to be an oral-drug candidate as it fulfills all Lipinski criteria and shows good cell membrane permeability. However, molecular docking showed that LC has weaker binding affinity values (-5.2 kcal/mol) than AZ-33 (-8.8 kcal/mol) to LDH-A. LC also interacts with different amino acid residues in LDH-A compared to AZ-33. Despite that, the molecular dynamic study revealed that LC forms more stable interactions with LDH-A. Conclusion: LC can bind to LDH-A with more stability than AZ-33, despite its weaker binding affinity to LDH-A and different interacting residues. Further study is needed to investigate the other mechanism that explains the effect of LC in inhibiting lactate accumulation.