Anti-neuroinflammatory capacity of fresh ginger is attributed mainly to 10-gingerol

Abstract

Despite the anti-neuroinflammatory capacity of ginger, the corresponding active constituents are unclear. This study analyzed the composition of fresh ginger ethanolic extract by using LC–MS. Inhibitory activities of fresh ginger extract and seven gingerol-related compounds on the neuro-inflammation were also evaluated by using a lipopolysaccharide (LPS)-activated BV2 microglia culture model. Except for zingerone and 6-gingerol, other gingerols and shogaols at a concentration of 20μM inhibited the production of nitric oxide, IL-1β, IL-6 and TNF-α as well as their mRNA levels in LPS-activated BV2 microglia. Blocking NF-κB activation was the underlying mechanism responsible for inhibiting the proinflammatory gene expression. Increasing the alkyl chain length enhanced the anti-neuroinflammatory capacity of gingerols yet, conversely, attenuated those of shogaols. 6-Gingerol was the most abundant compound in the fresh ginger extract, followed by 10-gingerol. Furthermore, fresh ginger extract exhibited a significant anti-neuroinflammatory capacity, which was largely owing to 10-gingerol, but not 6-gingerol.