Royal Jelly Attenuates LPS-Induced Inflammation in BV-2 Microglial Cells through Modulating NF-κB and p38/JNK Signaling Pathways.

Royal jelly (RJ), a hive product with versatile pharmacological activities, has been used as a traditional functional food to prevent or treat inflammatory diseases. However, little is known about the anti-inflammatory effect of RJ in microglial cells. The aim of this study is to assess the anti-inflammatory effects of RJ in lipopolysaccharide- (LPS-) induced murine immortalized BV-2 cells and to explore the underlying molecular mechanisms. Our results showed that in LPS-stimulated BV-2 cells, RJ significantly inhibited iNOS and COX-2 expression at mRNA and protein levels. The mRNA expression of IL-6, IL-1<italic>β</italic>, and TNF-<italic>α</italic> was also downregulated by RJ in a concentration-dependent manner. Additionally, RJ protected BV-2 cells against oxidative stress by upregulating heme oxygenase-1 (HO-1) expression and by reducing reactive oxygen species (ROS) and nitric oxide (NO) production. Mechanistically, we found that RJ could alleviate inflammatory response in microglia by suppressing the phosphorylation of I<italic>κ</italic>B<italic>α</italic>, p38, and JNK and by inhibiting the nucleus translocation of NF-<italic>κ</italic>B p65. These findings suggest that RJ might be a promising functional food to delay inflammatory progress by influencing the microglia function. [ABSTRACT FROM AUTHOR]