Flavonoids from sea buckthorn inhibit the lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages through the MAPK and NF-κB pathways

Abstract

Sea buckthorn has long been used as a functional food to regulate cholesterol, relieve angina, and diminish inflammation. Flavonoids are one of the main active components in sea buckthorn. We investigated the effects of sea buckthorn flavonoid (SF) treatment on two pathways that mediate inflammation, the mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) pathways, to explore the anti-inflammatory activity of SFs in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The LPS-induced over-production of nitric oxide (NO) and prostaglandin E2 (PGE) was inhibited by SFs through a mechanism related to the modulatory effects of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) genes. Additionally, SFs downregulated the production and mRNA expression of pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β. Moreover, SFs inhibited the phosphorylation of the p38 and stress-activated protein kinase/jun amino-terminal kinase (SAPK/JNK) MAPK pathways, and they reduced the nuclear translocation of NF-κB to prevent its activation by blocking the phosphorylation and degradation of inhibitor protein of NF-κB α (IκB-α). Based on these findings, SFs may exert their inhibitory effects on inflammation by regulating the release of inflammatory mediators through the MAPK and NF-κB pathways. SFs highlight the potential benefits of using functional foods with anti-inflammatory actions to combat inflammatory diseases.

Curcumin alleviates macrophage activation and lung inflammation induced by influenza virus infection through inhibiting the NF‐κB signaling pathway

“…Previous studies have revealed that NF‐κB signaling pathway is one of the most important pathways that are activated in macrophages under the pathogen challenge . Thus, we aimed to study whether the anti‐inflammatory ability of curcumin is associated with NF‐κB signaling pathway.…”

“…Previous studies have revealed that NF-κB signaling pathway is one of the most important pathways that are activated in macrophages under the pathogen challenge. [34][35][36][37][38] Thus, we aimed to study whether the anti-inflammatory ability of curcumin is associated with NF-κB signaling pathway. By examining the protein expression levels via Western Blotting, we found that IAV infection leads to the decrease in IκBα and cytosolic p65, while enhanced the levels of p-IκBα and nuclear p65.…”

Helicobacter hepaticus infection induces chronic hepatitis and fibrosis in male BALB/c mice via the activation of NF‐κB, Stat3, and MAPK signaling pathways

“…In addition, our data indicated that the upregulation of Il‐6 and Tnf‐α was modulated by the activation of NF‐κB, Jak‐Stat3, and MAPK signaling pathways. It has been documented that these signaling pathways play key roles in modulating the inflammatory responses . The Jak/Stat signaling pathway is closely involved in inflammation and regulates the cytokine signaling cascade .…”

“…It has been documented that these signaling pathways play key roles in modulating the inflammatory responses. 42,43 The Jak/Stat signaling pathway is closely involved in inflammation and regulates the cytokine signaling cascade. 44 Stat3 exerts decisive and context-dependent functions in inflammation, tissue survival, and carcinogenesis.…”

Analgesic Effect ofHippophae rhamnoidesExtract in Orofacial Pain in Rats

“…또한 quercetin 대사산물의 하나인 isorhamnetin은 산화적 스트레스의 원인물질인 reactive oxygen species (ROS) 생성을 차단함으로써 C2C12 세포에서 의 apoptosis 유발을 억제하였고 5) , nuclear factor (NF)-κB 신호의 조절을 통해 lipopolysaccharides (LPS)에 의해 유발 된 염증반응을 완화시켰다고 보고하였다 6) . 뿐만 아니라, 산 자나무잎 추출물이 NF-κB 활성화 및 p38 mitogen-activated protein kinase (MAPK)의 인산화를 억제함으로써 LPS에 의한 nitric oxide (NO), interleukin 6, tumor necrosis factor-alpha, inducible nitric oxide synthase 및 cyclooxygenase-2 단백질의 발현을 억제하였다는 보고는 산자나 무의 항산화 및 항염증 효과를 설명하는 연구결과이다 7) .…”