The regulatory effect of cardamonin on TLR4/MyD88/NF-κB/iNOS pathway / 中国药理学通报

Aim Toassesstheregulatoryeffectsofcar-damonin (CDN ) on toll-like receptor (TLR )-4/MyD88/NF-κB/iNOS signaling pathway in lipopolysac-charide (LPS )-stimulated RAW264. 7 macrophage cells.Methods LPS-stimulatedRAW264.7cells were divided into three groups:vehicle-treated group, LPS-treated group and LPS +CDN-treated group.Cell viability was assessed by CCK-8 assay.The concentra-tion of nitric oxide (NO)in cell culture medium was measured by Griess reagent.The mRNA levels of iN-OS,COX-2,MCP-1 ,TNF-α,IL-6 and IL-1βwere de-termined by reverse transcription real-time quantitative PCR(RT-qPCR).The protein levels of inducible nitric oxide synthase(iNOS),TLR4,myeloid differentiation factor 88(MyD88),nuclear factor κB(NF-κB)phos-phorylated (p )-p65 ,inhibitor κBα(IκBα),and p-IκBαweredeterminedbyWesternblot.Results 1~50 μmol·L-1 CDN had no cytotoxicity in RAW264. 7 cells.However,CDN inhibited the LPS-induced secre-tion of nitric oxide(NO)and mRNA expressions of iN-OS,COX-2,MCP-1 ,TNF-α,IL-6 and IL-1βin a dose-dependent manner.Moreover,50 μmol · L-1 CDN inhibited the LPS-induced up-regulation of iNOS, TLR4,MyD88,NF-κB p-p65,p-IκBαand down-reg-ulationofIκBα.Conclusion Cardamonininhibitsthe production of NO via a mechanism associated with the inhibition of TLR4/MyD88/NF-κB/iNOS pathway.

Advances in roles of NF-κB in regulating pathways of apoptosis / 中国药理学与毒理学杂志

Apoptosis is a process of programmed cell death that is controlled by genes. Normally, there are three regulation pathways involved in the process of apoptosis, including the signaling of intracel-lular mitochondria, endoplasmic reticula and extracellular death receptors. Recent studies showed that NF-κB is a key regulator in the process of apoptosis. NF-κB plays a promotional and a inhibitory role as well in the regulation of apoptosis, closely related to the the inhibitor of apoptosis proteins family, the B cell lymphoma/ lewkmia-2 family, tumor necrosis factor receptor associated factors, c-Jun N-terminal kinase, tumor necrosis factor related apoptosis inducing ligand and Fas-associated death domain protein-like interleukin-1β. Thus, investigation of the mechanism regarding NF-κB in apoptosis regulation is of great importance for apoptosis-related drug development. The paper reviews the recent research progress in the function of NF-κB in apoptosis pathway regulation.

Effects and mechanisms of vitexin against ulcerative colitis in mice / 中国药理学通报

Aim To evaluate the effect and mecha-nism of vitexin in a mouse model of DSS-induced ulcer-ative colitis (UC).Methods C57BL/6 mice were randomly placed into three groups: normal control group,DSS group and DSS +Vitexin group.Mice coli-tis was induced by adding 4% dextran sulphate sodium (DSS)into the drinking water for seven days.Vitexin was administered once a day along with DSS treatment. Mice were monitored daily with body weight change and diarrhea symptoms.After sacrifice,colon was re-moved and fixed in 1 0% (W/V)buffered formalin for hematoxylin-eosin (H&E)staining.Histological dam-age was assessed as a combined score of inflammatory cell infiltration and mucosal damage.The remaining colon pieces were collected to measure the activity of myeloperoxidase (MPO)by ELISA method and to de-termine the mRNA expression of TNF-α,IL-6 and COX-2.Results None of the mice receiving vehicle alone exhibited body weight loss and mucosal disrup-tion at any point during the study.Vitexin treatment significantly ameliorated DSS-induced body weight loss and histological score.The activity of MPO and the mRNA expression of TNF-α,IL-6 and COX-2 were markedly inhibited by vitexin treatment.Conclusion Vitexin ameliorates DSS-induced colitis through sup-pressing leukocyte infiltration and pro-inflammatory mediators production.