Proteomic approach to identify changes in protein expression modified by 17beta-oestradiol in bovine vascular smooth muscle cells.

The aim of the present study was to use proteomics to analyse modifications in the level of expression of different proteins in BVSMCs (bovine vascular smooth muscle cells) incubated in the absence and presence of 17beta-oestradiol. By using two-dimensional electrophoresis with a pH range of 4-7, we identified several areas on the gels in which the level of expression of proteins were different between control BVSMCs and cells incubated for 24 h with 17beta-oestradiol. Changes in several isoforms of alpha-enolase, HSP60 (heat-shock protein 60), vimentin and PDI (protein disulphide-isomerase) were observed in BVSMCs. The expression of alpha-enolase isoform 1 was enhanced after 17beta-oestradiol treatment. The expression of HSP60 isoform 3, vimentin isoforms 2 and 3 and caldesmon was reduced by 17beta-oestradiol. Finally, the expression of PDI isoforms was reduced by 17beta-oestradiol. In summary, 17beta-oestradiol modified the expression of isoforms of proteins associated with smooth muscle cell proliferation (alpha-enolase, vimentin and HSP-60), cell contraction (vimentin and caldesmon) and cell redox modulation (PDI). These findings confirm that 17beta-oestradiol may modulate a wide range of signalling pathways in vascular smooth muscle cells.