Molecular docking studies of curcumin analogs with phospholipase A2.

The enzyme phospholipase A2 is responsible for the hydrolysis of membrane phospholipids that release arachidonic acid, which serves as a substrate for pro-inflammatory mediators, such as prostaglandins and leucotriens. The binding of the substrate to PLA2 occurs through a well-formed hydrophobic channel. So blocking the hydrophobic channel is an effective way to inhibit PLA2. Compounds inhibiting PLA2 have been implicated as potential therapeutic agents in the treatment of inflammation related diseases. Curcumin is a well studied compound isolated from the plant Curcuma longa. The PLA2 inhibiting activity of curcumin has been studied in our laboratory. The present study focuses whether any of the curcumin analogs can bind PLA2 more strongly than curcumin. To check this, binding of twenty eight different curcumin analogs to PLA2 have been studied by molecular modeling and docking. The mode of interactions of compounds with strong binding are discussed and reported here. It has been observed that four analogs namely rosmarinic acid, tetrahydrocurcumin, dihydrocurucmin and hexahydrocurcumin possess better binding energy than curcumin. The present study may lead to the better understanding of PLA2 inhibition by curcumin analogs. This may help to develop better anti-inflammatory drugs.