Figure 2.

C2238/αANP induces ApoE downregulation through NPR-C-dependent mechanisms associated with the upregulation of miR199a and of Egr-1 in HUVSMCs. (a) Analysis by RT-PCR and by western blotting of ApoE expression levels upon CC2238/αANP in NPR-C not silenced and silenced cells. **P<0.0001 for CC2238/αANP versus all other samples. (b) miR199a-3p, miR199a-5p, DNAJA4 mRNA levels under either TT2238/αANP or CC2238/αANP (upper part of the panel) and in NPR-C not silenced and silenced cells under CC2238/αANP (lower part of the panel). Two specific siRNAs were used to obtain NPR-C gene silencing. **P<0.0001 for CC2238/αANP versus TT2238/αANP and CTR. ΔP<0.005 for TT2238/αANP versus CTR and for CC2238/αANP versus CTR (miR199a-3p and miR199a-5p). (c) Representative western blotting of Egr-1, with corresponding densitometric analysis under either TT2238/αANP or CC2238/αANP exposure (left side) and under CC2238/αANP in NPR-C not silenced and silenced cells (right side). **P<0.0001 for CC2238/αANP versus all other samples. Results are expressed as mean±S.D. Number of independent experiments=6. CC2238/αANP, variant αANP; TT2238/αANP, wild-type αANP; siRNA1, NPR-C gene silencer 1; siRNA2, NPR-C gene silencer 2; hsa-miR199a, human microRNA199a; Egr-1, early growth response protein-1; CTR, control