Kaempferol 3-O-(2G-glucosylrutinoside)-7-O-glucoside isolated from the flowers of Hosta plantaginea exerts anti-inflammatory activity via suppression of NF-κB, MAPKs and Akt pathways in RAW 264.7 cells

Abstract

Kaempferol 3-O-(2G-glucosylrutinoside)-7-O-glucoside (KGG) has isolated from Hosta plantaginea flowers and possessed an inhibitory effect on cyclooxygenase 2 (COX-2), could be effective in inhibiting inflammation. However, the anti-inflammatory activity and mechanism of KGG remain unknown. In this study, for the first time, the anti-inflammatory effect of KGG and its potential molecular mechanisms were explored in cells. KGG had no cytotoxicity at concentrations of 1.25, 2.5, 5, 10, 20, and 40 μM by Cell Counting kit-8 assay in RAW 264.7 cells. Besides, KGG concentration-dependently (1.25, 2.5, and 5 μM) inhibited secretions of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Western blot showed that the phosphorylation of nuclear factor kappa-B (NF-κB) p65, inhibitor of NF-κB (IκB), p38 MAPK, c-Jun N-terminal kinases (JNK), extracellular signal-regulated kinase (Erk), and protein kinase B (Akt), together with inducible nitric oxide synthase (iNOS) and COX-2 were significantly attenuated by KGG (1.25, 2.5, and 5 μM) in a concentration-dependent relationship. Meanwhile, KGG remarkably enhanced the protein expression of IκB. Taken together, KGG may be one of bioactive phytochemicals from H. plantaginea flowers, and be an anti-inflammatory agent via inhibiting NF-κB, mitogen-activated protein kinases (MAPKs), and Akt signaling pathways.