Extravascular rapamycin film inhibits the endothelial-to-mesenchymal transition through the autophagy pathway to prevent vein graft restenosis

A novel Nanocellulose-Gelatin-AS-IV external stent resists EndMT by activating autophagy to prevent restenosis of grafts

“…The rat autologous neck dynamic and static bypass model was used, known as the “Cuff method” [ 9 , 29 ]. Briefly, Sprague-Dawley rats (males; aged 10 weeks, body weight: 200 g) were classified into six groups: vein, artery, graft, plus stent, stent loading low dose AS-IV, and stent loading high dose AS-IV.…”

“…In our previous study, extravascular stents were able to inhibit endothelial-to-mesenchymal transition (EndMT) and thus inhibit restenosis of grafted veins [ 9 ]. EndMT is a complex process that contributes to neointimal formation in vein grafts.…”

“…NC-Gelatin hydrogels have good mechanical properties and stability and are suitable as tissue engineering scaffolds and drug delivery systems [ 16 , 26 , 27 ]. Previously, we prepared NC-Gelatin hydrogels as extravascular stents and demonstrated that they are tough, provide sufficient mechanical support to the vein graft in the early stage after implantation, and are biocompatible [ 9 , 28 , 29 ]. Furthermore, extravascular stents resist EndMT through autophagy, thus preventing restenosis of grafted veins [ 9 ].…”

“…Previously, we prepared NC-Gelatin hydrogels as extravascular stents and demonstrated that they are tough, provide sufficient mechanical support to the vein graft in the early stage after implantation, and are biocompatible [ 9 , 28 , 29 ]. Furthermore, extravascular stents resist EndMT through autophagy, thus preventing restenosis of grafted veins [ 9 ]. In vein grafting, the extravascular stent inhibits the secretion of IL-1β, activates autophagy, reduces twist expression, inhibits the process of EndMT, inhibits NIH, and prevents restenosis of grafted veins [ 9 , 30 ].…”

“…Furthermore, extravascular stents resist EndMT through autophagy, thus preventing restenosis of grafted veins [ 9 ]. In vein grafting, the extravascular stent inhibits the secretion of IL-1β, activates autophagy, reduces twist expression, inhibits the process of EndMT, inhibits NIH, and prevents restenosis of grafted veins [ 9 , 30 ]. Astragaloside-Ⅳ (AS-Ⅳ), one of the main components of Astragalus ( Astragalus membraneceus) , is commonly used in Chinese herbal medicine.…”