Figure 3.

GPR120, but not GPR40, modulated EPA-induced autophagy to inhibit Dex-induced apoptosis. GPR120 and GPR40 were knocked down by shRNA and cells were cultured with 10⁻⁶ M Dex and 100 μM EPA. (a and b) RT-PCR and western blot analysis of GPR120 and GPR40. mBMMSCs were invalidated for GPR120 and GPR40 expression or transfected with a non-targeting vector. (c and d) RT-PCR, western blot analysis, and quantification of LC3 (LC3-2/LC3-1) protein treated with certain groups. (e) Annexin V/PI double staining was performed to detect the apoptotic cells. (f) Caspase-3 activity was detected by the caspase-3 assay kit in mBMMSCs that were treated with 10⁻⁶ M Dex and EPA for 24 h. (g) Cultures were incubated with Dex (10⁻⁶ M) and EPA for 24 h and cell viability was determined by MTT assay. (h) Cell apoptosis was detected by TUNEL assay and number of TUNEL-positive cells as a percentage of the positively stained mBMMSCs. Expression of each target gene was calculated as a relative expression to β-actin and represented as normalized fold expression. The data are represented as the mean±S.D. of three independent experiments. *P<0.05 compared with GPR120 or GPR40 control cells (cells transfected with a non-targeting vector)