Additive Regulation of Adiponectin Expression by the Mediterranean Diet Olive Oil Components Oleic Acid and Hydroxytyrosol in Human Adipocytes (original) (raw)
Fig 5
Attenuation by HT and OA of TNF-α-induced inhibition of PPARγ expression and activity.
(A) SGBS cells were treated with 1 μmol/L HT, 10 μmol/L OA, or 1 μmol/L RSG in the absence or presence of the PPARγ antagonist GW9662 at 10 μmol/L (GW), and then stimulated with 10 ng/mL TNF-α for 24 h. Adiponectin levels in the culture medium were determined by ELISA, and expressed as percent of unstimulated control (CTL). Data are means ± SD (n = 3). #p<0.05 versus CTL. *p<0.05 versus TNF-α alone. †p<0.05 versus the compound-treated group without GW9662. (B) and (C) SGBS cells were treated with 1 μmol/L HT or 10 μmol/L OA before 10 ng/mL TNF-α stimulation for 24 h. (B) Whole-cell lysates were assayed by Western blotting using antibodies against PPARγ1, PPARγ2, and against β-actin, this last used as a loading control. Total PPARγ1 and PPARγ2 band intensities were normalized to β-actin, and are expressed as percent of unstimulated control (CTL). (C) Nuclear proteins were analyzed for PPARγ DNA-binding activity by ELISA as described in Methods. Data are expressed as percent of unstimulated control (CTL). (D) SGBS cells were treated with 1–10 μmol/L HT, or 10 μmol/L OA, or co-treated with OA + HT before 10 ng/mL TNF-α stimulation for 24 h. PPARγ mRNA levels were determined by qPCR and normalized to 18S RNA. Data are expressed as fold induction over unstimulated control (CTL). Bars represent means ± SD (n = 3). #p<0.05 versus CTL. *p<0.05 versus TNF-α. †p<0.05 versus each compound + TNF-α.