ABSTRACT
Objective To investigate the effects of ethanol extracts of Lepidium meyenii Walp (LMEE) from two different areas in Xinjiang on the maturation of mouse macrophages (RAW264. 7 cells) and dendritic cells (DCs). Methods Ethanol extracts of LMEE from Tashikuergan County (Ta xian) and A La gou of Xinjiang were prepared and named as LMEE-T and LMEE-A, respectively. RAW264. 7 cells and bone marrow-derived DCs from C57BL/6 mice were treated with different concentrations of LMEE-T/A. The viability of RAW264. 7 cells was analyzed by MTT assay. Expression of costimulatory molecules and MHCⅠ on the surface of RAW264. 7 cells and DCs was detected by flow cytometry. Secretion of cytokines and the release of nitrogen oxide (NO) were measured by ELISA and Griess method, respectively. Results LMEE-T/A had no significant influence on the viability of RAW264. 7 cells when the concentration was lower than 1 mg/ml. Treating RAW264. 7 cells with LMEE-T/A promoted surface molecule expression, cytokine secretion and NO release through TLR4 signaling pathway in a dose-dependent manner. Moreover, LMEE-T was more potent than LMEE-A. LMEE-T/A at the concentration of 0. 4 mg/ml promoted the expression of DC surface molecules and the secretion of cytokines. Infrared and ultraviolet spectra showed that LMEE-A and LMEE-T contained polysaccharides, macaenes, macamides and flavanols. Compared with LMEE-A, LMEE-T contained more benzene ring compounds but less polysaccharides. Conclusion Both LMEE-T and LMEE-A could activate RAW264. 7 cells and promote the maturation of DCs. The differences between their effects might be related to the differences in their contents.
ABSTRACT
Objective To investigate the effects of Artemisia absinthium L. ( A. absinthium L. ) extracts on the maturation and function of dendritic cells (DCs). Methods A. absinthium water (AAW) and ethanol ( AAE) extracts were prepared. DCs were separated into several groups and treated with differ-ent concentrations of AAW (containing 5, 50 and 150μg/ml of polysaccharide) and AAE (containing 0. 6, 3 and 6 μg/ml of flavonoid) , respectively. Cell viability, antigen phagocytosis and maturation of DCs were detected by flow cytometry. Levels of cytokines were analyzed by ELISA. Western blot assay was performed to analyze the activation of key molecules in NF-κB, mitogen-activated protein kinase ( MAPK) and janus kinase/signal transducer and activator of transcription ( JAK/STAT) signaling pathways. Results AAW promoted the maturation of DCs, significantly decreased antigen phagocytosis and increased cytokine produc-tion (IL-12p40 and TNF-α). AAE significantly enhanced the expression of co-stimulatory molecules on the surface of DCs and decreased antigen phagocytosis, but had no significant effect on cytokine production. Mo-reover, AAE significantly inhibited the LPS-induced expression of TNF-α, IL-12p40 and IL-6. Further anal-ysis revealed that AAW and AAE could activate the phosphorylation of p38, extra-cellular signal regulated kinase (ERK), IKKα/β, NF-κBp65 and JAK2. Besides, AAE could activate the phosphorylation of c-Jun N-terminal kinase ( JNK ) and inhibit the LPS-induced phosphorylation of inhibitor of NF-κB ( IκB-α) , IKKα/β, NF-κBp65, p38, ERK and JAK2. Conclusion AAW could enhance immunity and AAE could inhibit inflammation.
ABSTRACT
Objective To investigate the effects of water extracts of Lepidium meyenii walp (LMWE) collected from two different places in Xinjiang on the maturation and function of dendritic cells (DCs) and to evaluate their roles in immunoregulation. Methods Water extracts of LMWE growing in Tashikuergan County (Ta xian) and A La gou of Xinjiang were prepared and named as LMWE-T and LMWE-A,respectively. Bone marrow-derived DCs and splenocytes isolated from C57BL/6 mice were treated with different concentrations of polysaccharide extracts from LMWE-T/A. Effects of LMWE-T/A on the per-centage and apoptosis of DC,expression of co-stimulatory molecules and secretion of cytokines were detected by flow cytometry and ELISA. MTT assay was used to analyze the proliferation of splenocytes. Changes in the functions of DC were evaluated by mixed lymphocyte reaction(MLR). Results LMWE-T/A had no in-fluence on the percentage and viability of DC. Expression of CD40 and CD86,and secretion of TNF-α,IL-12p40 and IFN-γ were significantly increased by LMWE-T/A treatment in a dose-dependent manner. LMWE-T/A treatment enhanced the functions of DCs and also dose-dependently promoted the proliferation of splenocytes. LMWE-A was more effective than LMWE-T in promoting CD86 expression,IFN-γ secretion and splenocyte proliferation. Pretreatment with TAK-242,an inhibitor of Toll-like receptor 4(TLR4),could sig-nificantly inhibit the regulatory effects of LMWE-T/A on CD40 expression and the secretion of TNF-α and IL-12p40. Conclusion This study shows that LMWE could promote the maturation of DC through TLR4 signaling pathway,enhance the functions of DC without side effects on DC survival,and increase the prolif-eration of splenocytes,indicating that LMWE has a potential immunopotentiating effect. LMWE-A has better effects than LMWE-T on immune enhancement.
ABSTRACT
Objective To investigate the effects of crude extract of Capparis spinosa L. fruit alka-loids (CSFA) on the maturation of murine bone marrow-derived dendritic cells (DCs). Methods CSFA was prepared and the contents were determined by high performance liquid chromatography. DCs were trea-ted with different doses (1, 2, 3 mg/ml) of CSFA. The viability of DCs, the expression of surface mole-cules and the ability of phagocytosis were detected by flow cytometry. The secretion of cytokines was meas-ured by ELISA. Western blot assay was performed to analyze the activation of key molecules in mitogen-acti-vated protein kinases ( MAPK) and nuclear factor-kappa B ( NF-κB) signaling pathways. Results The re-sults showed that CSFA alone had no significant influence on the expression of surface molecules and cyto-kines in DCs. However, it significantly decreased the expression of CD40, CD80, CD86 and MHC Ⅱ as well as the secretion of IL-12p40 and TNF-αthat were induced by lipopolysaccharides (LPS), but increased IL-10 secretion and the ability of phagocytosis after treating DCs with both CSFA and LPS. Further, the phosphorylation of p38, extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) and the nuclear translocation of NF-κBp65 induced by LPS were inhibited by CSFA. Conclusion CSFA could inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines induced by LPS while in-creasing the secretion of the anti-inflammatory cytokine IL-10 and the ability of phagocytosis, which might in-volve MAPK and NF-κB signaling pathways. This study suggests that CSFA could be used as a potential im-munosuppressant.