Anti-Inflammatory and Analgesic Activities of the Saponin, Daucosterol, and the Triterpenoid Ester, β-Sitosterol 3-Myristate, From Capparis erythrocarpos (Isert) Capparaceae, and Their Interaction With the TRPV1 Ion Channel Transporter.

Abstract

Capparis erythrocarpos is a medicinal plant traditionally used as an antiarthritic, anti-inflammatory, and analgesic agent. However, no previous reports exist on the analgesic and acute anti-inflammatory activities of the individual chemical constituents from this plant. This study reports the isolation, characterization, and evaluation of analgesic and acute anti-inflammatory activities of chemical constituents from the root bark of C. erythrocarpos, including their modulatory effects on TRPV1 ion channel activity. The isolated compounds were characterized as daucosterol (DC) and β-sitosterol 3-myristate (SM) using NMR and LC/GC-MS. DC significantly (p < 0.05) inhibited both phases of carrageenan-induced edema in a reverse dose-dependent manner, demonstrating 58.38% anti-inflammatory activity at 2 mg/kg p.o., comparable to diclofenac sodium (DS) at 8 mg/kg p.o. (53.07%). SM inhibited only phase 2 of carrageenan-induced edema. Both compounds significantly inhibited cold-induced pain with superior analgesic activity compared to DS. Against inflammation-induced pain, DC showed the highest analgesic activity (47.37% at 2 mg/kg p.o.). Molecular docking studies revealed that DC and SM produced ΔG values of -10.60 and -9.80 kcal/mol, respectively, which are more negative than those of DS (-8.6 kcal/mol), suggesting that they might be superior TRPV1 ion channel inhibitors and that DS likely has additional mechanisms of action. These results demonstrate that DC and SM possess remarkable therapeutic properties, warranting further exploration for novel drug development.