Start Publications Epigallocatechin gallate mediated sandwich-like coating for ...
Attension

Epigallocatechin gallate mediated sandwich-like coating for mimicking endothelium with sustained therapeutic nitric oxide generation and heparin release

Year: 2021

Journal: Biomaterials, Volume 269, FEB

Authors: Zhang, Bo; Yao, Ruijuan; Hu, Cheng; Maitz, Manfred F.; Wu, Haoshuang; Liu, Kunpeng; Yang, Li; Luo, Rifang; Wang, Yunbing

Organizations: National Key Research and Development Program [2016YFC1102200, 2017YFB0702503]; National Natural Science Foundation of China [51703144]; Sichuan Science and Technology Major Project [2018SZDZX0011]; 111 Project (The Program of Introducing Talents of Discipline to Universities) [B16033]

Keywords: Cardiovascular stent; Sandwich-like; Layer-by-layer; Biomimetic endothelial function; Nitric oxide; Heparin

In-stent restenosis after stenting is generally characterized by an inflammatory response, excessive proliferation of smooth muscle cells, and delayed healing of the endothelium layer. In this study, inspired by catechol/gallol surface chemistry, a sandwich-like layer-by-layer (LBL) coating was developed using chitosan and heparin as polyelectrolytes, along with the embedding of an epigallocatechin gallate/copper (EGCG/Cu) complex. The embedding of EGCG stabilized the coating by various intermolecular interactions in the LBL coating (e.g., pi-pi stacking, weak intermolecular crosslinking, and enriched hydrogen bonding) and supported the sustained release of the cargo heparin over 90 days. This design enabled a biomimetic endothelium function in terms of the sustained release of heparin and continuous in situ generation of nitric oxide, driven by the catalytic decomposition of endogenous S-nitrostothiols by copper ions. The result showed enhanced durability of anticoagulation and suppressed inflammatory response. Moreover, the sandwich-like coating supported the growth of endothelial cells and up-regulated the protein expression of vascular endothelial growth factor, while effectively suppressing the proliferation and migration of smooth muscle cells (SMCs) via the up-regulation of cyclic guanosine monophosphate. Ex vivo and in vivo experiments demonstrated the effectiveness of the sandwich-like coating in preventing thrombosis formation, suppressing the growth of SMCs, reducing the infiltration and activation of inflammatory cells, and ultimately achieving rapid in situ endothelialization. Hence, the EGCG-assisted sandwich-like coating might be used as a robust and versatile surface modification strategy for implantable cardiovascular devices.