Title : Evaluating mitigated and regulated effects of spontaneous fermented coffee on Lipopolysaccharide (LPS)-treated RAW264.7 macrophages
Abstract:
Spontaneous fermentation by indigenous microorganisms has been widely applied to coffee beans processing once harvested. Chemical composition of coffee beans and its physiological impacts after consumption could be changed during fermentation so that affect its potential protective effects on human health. However, the anti-inflammatory properties of fermented coffee extracts are still unknown. Therefore, in this research, phenolic composition, in vitro anti-inflammatory potential, and regulation pathway of fermented and unfermented Coffea arabica coffee extracts were investigated at light roasting levels. Totally, 48 phenolic compounds were tentatively characterized through LC-ESI-QTOF-MS/MS. Amongst, 24 phenolic compounds were particularly detected from the fermented coffee extract where mainly adopted by phenolic acids and flavonoids, while only 6 from the unfermented. The anti-inflammatory performance was evaluated in lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophage cell line. Fermented coffee extract better protected against LPS-induced cell death and decreased the nitric oxide (NO) production after 48 hours. Moreover, for cell morphology, the dendritic differentiation of macrophage as well as the mRNA expression of potential transcriptional factors (c-FOS and Socs1) was significantly alleviated by fermented coffee extract. For their acuate impact on genes, the mRNA expression of anti-inflammatory cytokines, including IL-10 and SOD2, was significantly higher after 4 hours fermented coffee extract treatment. For pro-inflammatory cytokines, both type of coffee extract reduced the expression of TNF-α, Socs3, and COX-2 however aggravated that of CCL2, IL-6, and IL-1β in a similar trend. Therefore, it suggested that coffee extract might down-regulate inflammatory reactions mainly through MAPK and JAK-STAT pathway correlated with the response of oxidative stress. Furthermore, spontaneous fermentation of coffee could provide benefits on its anti-inflammatory and regulatory effects through the liberation and microbial metabolization of phenolic compounds. In a long-term aspect, regular consumption of fermented coffee would be more highly potential to control the risk of chronic reactions and relevant diseases.
