Flavonoids of Polygonum hydropiper L. attenuates lipopolysaccharide-induced inflammatory injury via suppressing phosphorylation in MAPKs pathways

Abstract

Background Polygonum hydropiper L. is widely used as a traditional remedy for the treatment of dysentery, gastroenteritis. It has been used to relieve swelling and pain, dispel wind and remove dampness, eliminate abundant phlegm and inflammatory for a long time. Previous study showed that antioxidants especially flavonoids pretreatment alleviated sepsis-induced injury in vitro and in vivo. In the present study, the possible anti-inflammatory effect of flavonoids from normal butanol fraction of Polygonum hydropiper L. extract (FNP) against inflammation induced by lipopolysaccharide (LPS) was evaluated in vivo and in vitro.MethodsThe content of total flavonoid of FNP was determined by the aluminum colorimetric method. The content of rutin, quercetin and quercitrin was determined by HPLC method. Mice received FNP orally 3 days before an intra-peritoneal (i.p.) injection of lipopolysaccharide (LPS). Total superoxidase dismutase (T-SOD), total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-PX), glutathione (GSH), myeloperoxidase (MPO) and malondialdehyde (MDA) levels were measured. Tumor necrosis factor-α levels in serum and tissue was measured. mRNA expressions of pro-inflammatory cytokines in lung were assessed by Real-Time PCR. Histopathological changes were evaluated in lung, ileum and colon. We also investigated FNP on reactive oxygen species (ROS), nitric oxide (NO) and pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8) production, inducible nitric oxide synthase (iNOS), Cyclooxygenase-2 (COX-2) protein expression, phosphorylation of MAPKs and AMPK in LPS-stimulated RAW264.7 cells.ResultsFNP increased the levels of T-SOD, T-AOC, GSH-PX and GSH, decreased the levels of TNF-α, MPO and MDA, attenuate the histopathological lesion in LPS-stimulated mice. FNP inhibited production of inflammatory cytokines, ROS and NO, protein expressions of iNOS and COX-2, phosphorylation of ERK, JNK and c-JUN in MAPKs, promoted phosphorylation of AMPKα suppressed by LPS.ConclusionThese results suggested in vivo anti-inflammatory activities of FNP might contributed to its enhancement in antioxidant capacity, its inhibitory effects may be mediated by inhibiting the phosphorylation of JNK, ERK and c-JUN in MAPKs signaling pathways.

Natural product derived phytochemicals in managing acute lung injury by multiple mechanisms

“…S. Y. Hu. The flavonoids of Polygonum hydropiper L. mainly contain rutin, quercetin, hyperoside and quercitrin, which have been found to inhibit LPS-induced ALI through suppressing MAPK signaling pathway [ 104 ]. Flavonoids from Houttuynia cordata containing 8.8 % rutin, 26.7 % hyperoside and 31.7 % quercitrin have been found to alleviate H1N1-induced ALI in mice, which was related to anti-viral and anti-inflammatory effects through suppressing influenzal NA activity and TLR signaling [ 105 ].…”

Extraction Process, Component Analysis, and In Vitro Antioxidant, Antibacterial, and Anti-Inflammatory Activities of Total Flavonoid Extracts from Abutilon theophrasti Medic. Leaves

“…To better understand the mechanisms underlying the anti-inflammatory action, we assessed the effect of TFE from A. theophrasti leaves on the MAPK signaling pathways, which are other important signaling pathways for modulating inflammation [ 57 , 58 ]. The inhibitory effect of TFE on inflammation was investigated by studying the MAPK signaling pathways.…”

Flavonoid-rich extract of Polygonum capitatum attenuates high-fat diet–induced atherosclerosis development and inflammatory and oxidative stress in hyperlipidemia rats

“…The observed positive effects might due to the flavonoids in FPC and the results were according to the previous study. 13 The nuclear receptor PPARα is used to treat dyslipidemia and modulates the mRNA expression of encoding proteins that are referred to fatty acid oxidation and lipid metabolism. 14 LDLR plays an important role in lipoprotein metabolism by decreasing the plasma LDL-C content.…”