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This study is to explore the effect of ginkgolide B (BN52021) on the production of nitric oxide (NO), interleukin (IL)-6 and regulated upon activation normal T cell expressed and secreted (RANTES) from astrocytes induced by stimulators. Primary cultured rat astrocytes were stimulated with lipopolysaccharides (LPS), the production of NO was assayed using Griess reaction; U251 cells were stimulated with IL-1 beta, the contents of IL-6 and RANTES in the supernatant were measured using ELISA. The mRNA expressions of IL-6 and RANTES were detected using RT-PCR. LPS (10 ng mL(-1) to 10 microg mL(-1)) could stimulate rat astrocytes to produce NO in a dose-dependent manner. Ginkgolide B at the concentrations of 0.1-10 micromol L(-1) were shown to decrease NO production significantly. IL-1 beta could induce the mRNA expression and protein secretion of IL-6 from U251 cells, as well as RANTES. Ginkgolide B at concentrations of 0.1-10 micromol L(-1) were shown to inhibit RANTES secretion, and to inhibit mRNA expression of IL-6 and RANTES at concentration of 10 micromol L(-1). Ginkgolide B has inhibitory effect on the production of NO, IL-6 and RANTES from astrocytes treated with inflammatory stimulators.

This study is to explore the effects of extracts of Cheezheng pain relieving plaster (ECPRP) on nitric oxide (NO) production and expression of inducible nitric oxide synthase (iNOS) in macrophages induced by LPS and the mechanism involved. Nitric oxide level was measured with Griess reagent assay. Inducible nitric oxide synthase (iNOS) protein and NF-kappaBp65 fragment were detected with Western blotting. ECPRP (62.5 and 125 mgL(-1)) significantly inhibited the increase of nitric oxide level. Furthermore, ECPRP (62.5 and 125 mg x L(-1)) notably reduced the expression of iNOS mRNA and protein. ECPRP (62.5 and 125 mg x L(-1)) elevated the content of I-kappaB protein in cytoplasm, while decreased the content of NF-kappaBp65 protein in nucleus. These results suggest that ECPRP reduce nitric oxide level via down-regulation of NF-kappaB-iNOS-nitric oxide pathway, resulting in prevention of inflammation.

Aim: To study the inhibitory effect of ginkgolide B (BN52021) on the PAF induced changes of chemotaxis of murine peritoneal macrophages and the related polymerization of F-actin., Methods: Chemotaxis assays were performed using a modified 48-well Boyden chamber. Actin polymerization of murine peritoneal macrophages was analyzed by flow cytometry using a specific fluorescent stain., Results: Peritoneal macrophages significantly migrated toward platelet-activating factor (PAF) through a micropore filter; however, in the presence of PAF receptor antagonist BN52021 (0.01 nmol x L(-1) -0.1 micromol x L(-1)), the migration was significantly inhibited. Moreover, BN52021 inhibited the actin polymerization of murine peritoneal macrophages induced by PAF in the presence of Ca2+, but not in Ca2+ -free medium., Conclusion: The results suggested that preventing polymerization of F-actin may be a pathway by BN52021 to inhibit the chemotaxis of macrophages, and this effect seems to be Ca2+ dependent. The data further indicated that inhibition of PAF induced macrophage chemotaxis is an important mechanism underlying the anti-inflammatory action of BN52021.

Aim: To study the effects of ginkgolide B on lipopolysaccharide (LPS)--induced TNFalpha production in mouse peritoneal macrophages and NF-kappaB activation in rat pleural polymorphonuclear leukocytes., Methods: L929 crystal violet staining assay was used to show the level of TNFalpha released from mouse peritoneal macrophages induced by LPS. Electrophoretic mobility shift assay (EMSA) was used to determine NF-kappaB binding activities., Results: Ginkgolide B (1, 10 micromol x L(-1)) was shown to significantly inhibit LPS (10 mg x L(-1))-induced TNFalpha production in mouse peritoneal macrophages, the IC50 was 0.26 micromol x L(-1); LPS (1 mg x L(-1)) and PAF (1 nmol , L(-1)) were shown to increase the NF-kappaB binding activities in rat pleural polymorphonuclear leukocytes; ginkgolide B (10 micromol x L(-1)) was found to inhibit LPS (1 mg x L(-1))-induced NF-kappaB activation in rat pleural polymorphonuclear leukocytes; ginkgolide B (1, 10 micromol x L(-1)) was shown to inhibit PAF (1 nmol x L(-1))-induced NF-kappaB activation in rat pleural polymorphonuclear leukocytes., Conclusion: The inhibition of NF-kappaB activation and TNFalpha production might be considered to be part of the mechanisms underlying the antiinflammatory action of ginkgolide B; PAF is involved in activation of the NF-kappaB pathway stimulated with LPS.