Dihydromyricetin inhibits proliferation and migration of gastric cancer cells through regulating Akt/STAT3 signaling pathways and HMGB1 expression / 南方医科大学学报

OBJECTIVE@#To investigate the inhibitory effects of dihydromyricetin on the proliferation and migration of gastric cancer BGC-823 cells and explore the molecular mechanisms.@*METHODS@#BGC-823 cells in routine culture were treated with different concentrations of dihydromyricetin (0, 40, 60, 80, 100, and 120 μg/mL) for 24 h, and the changes in cell viability were detected using CCK-8 assay; colony forming assay and Transwell assay were performed to assess the changes in colonyforming and migration abilities of the cells, respectively. The levels of MMP-2 and MMP-9 in the treated cells were determined using ELISA, and Western blotting was used to detect the expressions of E-cadherin, N-cadherin, cyclin D1, cyclin E1, HSP70 and HMGB1 and the phosphorylation levels of Akt and Stat3.@*RESULTS@#CCK-8 assay showed that dihydromyricetin treatment dose-dependently inhibited the viability of BGC-823 cells (@*CONCLUSIONS@#Dihydromyricetin inhibits the proliferation and migration of BGC-823 cells through suppressing the activation of Akt/stat3 signaling pathways and HMGB1 expression.

Calenduloside E inhibits lipopolysaccharide-induced inflammatory response by inhibiting activation of ROS-mediated JAK1-stat3 signaling pathway in RAW264.7 cells / 南方医科大学学报

OBJECTIVE@#To investigate the effect of calenduloside E on lipopolysaccharide (LPS)-induced inflammatory response in RAW264.7 cells and explore the underlying molecular mechanism.@*METHODS@#CCK-8 assay was used to examine the effect of different concentrations of calenduloside E (0-30 μg/mL) on the viability of RAW264.7 cells. The release of the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in RAW264.7 cells in response to pretreatment with 6, 8, and 10 μg/mL calenduloside E for 2 h followed by stimulation with 100 ng/mL LPS was detected using enzyme-linked immunosorbent assay (ELISA). The expression levels of iNOS and COX-2 and the activation of JAK-stats, MAPKs and NF-кB signaling pathways in the treated cells were determined using Western blotting. A reactive oxygen species (ROS) detection kit was used to detect ROS production in the cells, and the nuclear translocation of the transcription factor stat3 was observed by laser confocal microscopy.@*RESULTS@#Calenduloside E below 20 μg/mL did not significantly affect the viability of RAW264.7 cells. Calenduloside E dose-dependently decreased the expression levels of iNOS and COX-2 induced by LPS, inhibited LPS-induced release of TNF-α and IL-1β, and suppressed LPS-induced JAK1-stat3 signaling pathway activation and stat3 nuclear translocation. Calenduloside E also significantly reduced ROS production induced by LPS in RAW264.7 cells.@*CONCLUSIONS@#Calenduloside E inhibits LPS-induced inflammatory response by blocking ROS-mediated activation of JAK1-stat3 signaling pathway in RAW264.7 cells.

Apoptosis effect of Siraitia grosvenorii extracts on lung cancer cells A549 and its mechanisms / 中国药理学通报

Aim To study the apoptosis effect of Sir-aitia grosvenorii extract on human lung cancer cells A549 and its mechanisms.Methods MTT assay was applied to determine A549 cell proliferation.Hoechst 33258 staining was applied to investigate morphological changes in A549 cells.To find out the cause of cell growth inhibition,several experiments on cell cycle distribution and apoptosis were performed by flow cy-tometry analysis.The expression of p21 and Bcl-2 was determined by Western blot.Results Flow cytometry analysis showed that treatment with mogrol arrested A549 cells in the G0 /G1 phase and induced apoptosis. After treatment with Siraitia grosvenorii extract,West-ern blot experiment showed cell cycle regulator p21 was up-regulaed,while the apoptosis inhibitor Bcl-2 was down-regulated.Conclusion Treatment with Siraitia grosvenorii extract arrests the A549 cells at G0 /G1 phase and induces apoptosis that may contribute to the anti-proliferation activity of mogrol through the regula-tion of p21 and Bcl-2 expression.