A method for coating fucoidan onto bare metal stent and in vivo evaluation

Polysaccharide, despite its effect, is hard to apply for coating on stent surface because its own properties such as insoluble in water, fragmentation and deactivation easily. The aim of this study was to optimize the coating conditions for fucoidan on a bare metal stent (BMS), and to evaluate the inhibitory effect of a fucoidan-coated stent on in-stent restenosis (ISR). Three different coating approaches were attempted (designated as multi-layer coating, single-layer coating, and dual coating). Unlike other approaches, it was hard to notice the irregular, blotched or the cracks area in the polymer on the BMS surface in dual coating group. And the release of fucoidan was continued to 24 h and inhibits smooth muscle cell proliferation, when compared to the control, with approximately 42.7% at 3 days and 51.3% at 7 days of culture. In animal study using rabbit iliac artery, histopathological restenosis area were smaller in fucoidan-coated group compared to BMS group (38.6%, p = 0.062 in 148. 9 μg/stent, and 40.6%, p = 0.048 in 250 μg/stent of fucoidan coating group at 4 weeks of post-implantation) and a lower degree of strut coverage were shown in the fucoidan-coated stent group, as compared to the BMS group. These results suggest that dual coating is an appropriate method for fucoidan coating on BMS, and its inhibitory effect can be utilized for the suppression of ISR.