Schizandra arisanensis extract attenuates cytokine-mediated cytotoxicity in insulin-secreting cells

Figure 4 Characterizing the impact of ethanolic extract of Schizandra arisanensis on cytokine signal transduction. A: BRIN-BD11 cells stimulated with the cytokine mix in the presence or absence of ethanolic extract of Schizandra arisanensis (SA-Et) (20 μg/mL) were harvested after 30 min treatment for Western blot with the indicated antibodies. A representative Western blot from three experiments is shown; B: BRIN-BD11 cells stimulated with the cytokine mix in the presence or absence of SA-Et were harvested after 60 min treatment to measure IκBα protein level. A representative Western blot from three experiments is shown; C: Cytokine-induced inducible nitric oxide synthase (iNOS) mRNA levels in BRIN-BD11 cells during 24 h were determined by an reverse transcription-polymerase chain reaction. Relative iNOS gene expression was calculated by employing endogenous β-actin mRNA level as an internal control. The maximum iNOS gene expression at 4 h post-treatment with the cytokines alone was set to 100%. Data are presented as the mean ± SE, n = 4; D: Changes in cytokine-induced iNOS mRNA levels in BRIN-BD11 cells at 4 h in the presence or absence of the SA-Et (20 μg/mL) were also determined by real-time reverse transcription-polymerase chain reaction. β-actin was used as an internal control. The relative quantification of iNOS mRNA was presented as 2^-ΔΔct. Data are presented as the mean ± SE, n = 3. ^bP < 0.01 vs cells under control conditions; E: Nitric oxide production in cytokine-treated BRIN-BD11 cells in the presence or absence of the SA-Et (0-20 μg/mL) or nitro-L-arginine methyl ester (L-NAME) (0.5 mmol/L) was determined. Data are presented as the mean ± SE, n = 4. ^bP < 0.01 vs cells treated with the cytokine mixture alone. IL-1β: Interleukin 1β; IFN-γ: Interferon-γ.