Synthesis, Characterization and in vitro, in vivo and in silico Anti-Inflammatory Studies of the Novel Hybrid Based on Ibuprofen and 3-Hydroxy-Copalic Acid Isolated from Copaiba Oil (Copaifera multijuga)

Abstract

A novel anti-inflammatory hybrid 3-ibuprofenyl-copalic acid (3-IbuCA) was synthesized from 3-hydroxy-copalic acid isolated from Amazonian copaiba oil (Copaifera multijuga Hayne), and the anti-inflammatory ibuprofen. After full characterization, several assays to verify its anti-inflammatory effects were performed in vitro, in vivo and in silico (molecular docking). Induced fit docking was performed to observe the interactions with the enzymes cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). In vitro tests of cytotoxicity and tumor necrosis factor (TNF)-α inhibition, and in vivo tests of pleurisy, protein expression and gastrocytotoxicity were performed. Molecular docking studies with COX-1 and 2 showed binding free energies (ΔG) of −2.2 and −7.8 kcal mol−1, respectively, while for mofezolac and indomethacin, the binding free energies ΔG presented values of −8.5 and −10.1 kcal mol−1, which makes 3-IbuCA selective for COX-2 inhibition. This hybrid showed no toxicity against human macrophage at concentrations up to 2 µM, and inhibited TNF-α production in lipopolysaccharide (LPS)-stimulated macrophages. In the pleurisy assays, 3-IbuCA reduced the total leukocytes and mononuclear cells, which was followed by reduction of p-IKBα (phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) protein expression. Compared with ibuprofen alone, the hybrid caused less gastric damage. Thus, the docking, together with in vitro and in vivo studies suggest that this novel hybrid has potential as a new anti-inflammatory agent.