Phytochemical investigation of the ethyl acetate extract from the aerial parts of Pouzolzia pentandra led to the isolation and identification of fourteen compounds (1-14). These include known compounds such as β-sitosterol (1), bauerenol (2), oleanolic acid (3), 3β-friedelanol (4), kaempferol (5), quercetin (6), 2',6'-dihydroxy-3',4'-dimethoxychalcone (7), friedelan-3-one (8), dipterocarpol (9), 3β-hydroxyolean-12-en-28-one 3-p-coumarate (10), daucosterol (11), astilbin (12), 3-methoxy-4-hydroxybenzoic acid (13), and pouzolignan F (14). Among these, compound 14 displayed the most potent inhibitory activity on nitric oxide (NO) production in LPS-stimulated RAW264.7 macrophages, with an IC50 value of 10.54 ± 0.4 µM. Mechanistic studies further revealed that compound 14 significantly suppressed the LPS-induced release of key pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). Furthermore, it inhibited the activation of the nuclear factor-kappa B (NF-κB) signaling pathway by preventing the nuclear translocation of its p65 subunit. Molecular docking studies were performed to evaluate the anti-inflammatory potential of compound 14 against cyclooxygenase-2 (COX-2) and phosphodiesterase-4 (PDE4). The compound exhibited binding affinities of -6.138 kcal/mol and -9.361 kcal/mol for COX-2 and PDE4, respectively. Subsequent molecular dynamics (MD) simulations confirmed the formation of a stable complex with the active site of PDE4. Collectively, these integrated in vitro and in silico findings demonstrate that pouzolignan F acts as a multi-target anti-inflammatory agent, likely through the inhibition of inflammatory mediators, cytokines, and the NF-κB pathway.
Do et al. (Wed,) studied this question.