Antioxidant and anti-inflammatory activities of Gynura procumbens flowers extract through suppressing LPS-induced MAPK/NF-κB signalling pathways

ABSTRACT

Gynura procumbens is a traditional herb and food extensively cultivated in China and Southeast Asian countries. This study was designed to determine the content of the main chemical components and elucidate the antioxidant and anti-inflammatory capacity of G. procumbens flowers extracts (GPFE). GPFE was rich in flavonoids and phenolics and exhibited great reducing power as well as strong scavenging ability of ABTS⁺ and DPPH radicals. The pro-inflammatory factors including IL-6, IL-1β, NO, TNF-α, PGE₂ and their mRNA transcriptions were strongly inhibited with the treatment of GPFE in LPS-stimulated RAW264.7 macrophages. Meanwhile, GPFE could attenuate the inflammation via suppressing the nuclear translocation of NF-κB p65 and downregulating the MAPK signalling pathways. Furthermore, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C isolated from GPFE all had a high content and showed potent anti-inflammatory activities. Our findings suggest that GPFE could be used as a natural anti-inflammatory agent.