Black tea extract prevents lipopolysaccharide-induced NF-κB signaling and attenuates dextran sulfate sodium-induced experimental colitis

Abstract

BackgroundBlack tea has been shown to elicit anti-oxidant, anti-carcinogenic, anti-inflammatory and anti-mutagenic properties. In this study, we investigated the impact of black tea extract (BTE) on lipopolysaccharide (LPS)-induced NF-κB signaling in bone marrow derived-macrophages (BMM) and determined the therapeutic efficacy of this extract on colon inflammation.MethodsThe effect of BTE on LPS-induced NF-κB signaling and pro-inflammatory gene expression was evaluated by RT-PCR, Western blotting, immunofluorescence and electrophoretic mobility shift assay (EMSA). The in vivo efficacy of BTE was assessed in mice with 3% dextran sulfate sodium (DSS)-induced colitis. The severity of colitis was measured by weight loss, colon length and histologic scores.ResultsLPS-induced IL-12p40, IL-23p19, IL-6 and IL-1β mRNA expressions were inhibited by BTE. LPS-induced IκBα phosphorylation/degradation and nuclear translocation of NF-κB/p65 were blocked by BTE. BTE treatment blocked LPS-induced DNA-binding activity of NF-κB. BTE-fed, DSS-exposed mice showed the less weight loss, longer colon length and lower histologic score compared to control diet-fed, DSS-exposed mice. DSS-induced IκBα phosphorylation/degradation and phosphorylation of NF-κB/p65 were blocked by BTE. An increase of cleaved caspase-3 and poly (ADP-ribose) polymerase (PARP) in DSS-exposed mice was blocked by BTE.ConclusionsThese results indicate that BTE attenuates colon inflammation through the blockage of NF-κB signaling and apoptosis in DSS-induced experimental colitis model.

Three Pathways Assess Anti-Inflammatory Response of Epicatechin with Lipopolysaccharide-Mediated Macrophage RAW264.7 Cells

“…The extracts of tea and cocoa had noticeable anti‐inflammatory functions (Song et al . ; Khan et al . ).…”

“…Catechins are abundant flavonoids in tea and cocoa. The extracts of tea and cocoa had noticeable anti-inflammatory functions (Song et al 2011;Khan et al 2014). The EGCG is the most widely studied catechin for its anti-inflammatory effects.…”

Crude extract of Fuzhuan brick tea ameliorates DSS‐induced colitis in mice

“…To model human IBD, a DSS‐induced mouse model was setup and has been used for evaluation of potential medications. DSS is directly cytotoxic to enterocytes of the basal crypts and leads to breakdown of intestinal barrier integrity, translocation of enteric microbiota and induction of colitis (Song et al ., ). In this study, all of the mice administrating with DSS showed body weight loss, colon swelling and shortening.…”

Anti-inflammatory effect of ethanolic extract from Myagropsis myagroides on murine macrophages and mouse ear edema

“…Like NO and PGE 2 produced by iNOS and COX-2, respectively, the release of pro-inflammatory cytokines is regulated by NF-κB pathway and plays an important role in the induction of the innate immune response of the acquired immune response [23]. It has been well studied that the inhibition of NF-κB activation by black tea extract is associated with the phosphorylation, ubiquitination, and subsequent degradation of IκB via ubiquitin-proteosome pathway [24]. Although biochemical actions of EMM on NF-κB regulations remain unknown, the present study showed that EMM potentially inhibits the proteolytic degradation of IκB-α and the NF-κB promoter-driven luciferase expression induced by LPS in RAW 264.7 cells.…”