Heterophragma adenophyllum is a traditional medicinal plant that has been used as anti-inflammatory and to relief muscular tension. In the current research, four isolated constitutes namely lapacho (1), peshawaraquinone (2), indanone derivatives (3), α-lapachone (4) of H. adenophyllum were tested for anti-inflammatory effect using the carrageenan- and histamine-induced paw edema paradigm. The tested compounds (1-4) were evaluated for anti-inflammatory effect during the early and late phase of edema induction. In the early phase, all tested compounds (0.5 2.5 mg/kg each i.p.) demonstrated less than 50% effect, while in the later phase, compounds (2 and 3) demonstrated 85.66 and 89.87% attenuation. In addition, compounds (1-4) were subjected to histamine-induced inflammation, where compounds 2 and 3 exhibited excellent effects 86.87 and 89.98%, respectively at 5 mg/kg after the 2nd hour of administration, whereas compounds 1 and 4 did not exhibit any significant effect as compared with the negative control. Molecular docking results revealed a very high potency of compound based on the protein-ligand interaction (PLI) profile, which was further evaluated through a molecular dynamic simulation study. Therefore, the anti-inflammatory effect of H. adenophyllum attributed to the presence of these bioactive compounds (1-4) strongly supports the traditional uses of H. adenophyllum for treatment of inflammation. However, compounds 2 and 3 which exerted anti-inflammatory effect must be subjected for further mechanistic studies.
Keywords: Heterophragma adenophyllum; docking; inflammation; phytochemicals.