Pioglitazone Ameliorates Atorvastatin-Induced Islet Cell Dysfunction through Activation of FFA1 in INS-1 Cells

Figure 5

Effect of atorvastatin, pioglitazone, and FFA1-PLC signaling pathway inhibitors on the expression of PDX-1 and BETA2/NeuroD in INS-1 cells. (a) The expression of FFA1 mRNA was inhibited in rat FFA1 siRNA-transfected cells. (b and c) Administration of 10 μM pioglitazone enhanced the mRNA expression of PDX-1 and BETA2/NeuroD reduced by 20 μM atorvastatin in INS-1 cells, and the enhancement was suppressed by knockdown of FFA1 using siRNA or the PLC inhibitor U-73122 in INS-1 cells. (d, e, and f) Administration of 10 μM pioglitazone enhanced the protein expression of PDX-1 and BETA2/NeuroD reduced by 20 μM atorvastatin, and the enhancement was abolished by FFA1 siRNA and U-73122 in INS-1 cells. Negative control siRNA (NC-siRNA) was used for cell transfection as negative control to rule out any nonspecific effects that the siRNA transfection might have on cell function. β-Actin was detected as control. Each experiment was repeated at least three times. and compared to negative control. and compared to 20 μM atorvastatin treatment alone. and compared to 20 μM atorvastatin and 10 μM pioglitazone treatment together.

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