Phenethylferulate as a natural inhibitor of inflammation in LPS-stimulated RAW 264.7 macrophages: focus on NF-κB, Akt and MAPK signaling pathways

Abstract

Abstract Background Notopterygii Rhizoma et Radix (NRR) is commonly used for the treatment of inflammation-linked diseases. Phenethylferulate (PF) is high content in NRR crude, but its anti-inflammatory effect remains unclear. Therefore, we aimed to investigate the anti-inflammatory properties of PF and its underlying molecular mechanisms in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods The effect of PF on cell viability was measured by MTT assay. The anti-inflammatory properties of PF were studied by detecting the levels of inflammatory mediators and cytokines using enzyme-linked immunosorbent assay (ELISA). Furthermore, the anti-inflammatory mechanisms of PF were determined by Western blot analysis. Results PF was not cytotoxic to RAW 264.7 macrophages at the concentrations of below 48 μM. ELISA showed that PF conspicuously inhibited overproduction of prostaglandin E2 (PGE2), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and interleukin 6 (IL-6). Western blot analysis showed that PF remarkably suppressed overproduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2), the phosphorylation of inhibitor of NF-κB kinase α (IκB-α), protein kinase B (Akt), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinases (JNK) and p38, as well as the degradation and subsequent nuclear translocation of p65. Conclusions PF is a potent inhibitor of inflammation acting on nuclear factor kappa-B (NF-κB), Akt and mitogen-activated protein kinase (MAPK) signaling pathways in LPS-stimulated RAW 264.7 macrophages. This work provides evidence for the suitability of PF as a therapeutic candidate for the management of inflammatory-mediated immune disorders.