Restoring endothelial function: shedding light on cardiovascular stent development

Bioactive Metal-Organic Frameworks as a Distinctive Platform to Diagnosis and Treat Vascular Diseases

Vascular diseases (VDs) pose the leading threat worldwide due to high morbidity and mortality. The detection of VDs is commonly dependent on individual signs, which limits the accuracy and timeliness of therapies, especially for asymptomatic patients in clinical management. Therefore, more effective early diagnosis and lesion-targeted treatments remain a pressing clinical need. Metal-organic frameworks (MOFs) are porous crystalline materials formed by the coordination of inorganic metal ions and organic ligands. Due to their unique high specific surface area, structural flexibility, and functional versatility, MOFs are recognized as highly promising candidates for diagnostic and therapeutic applications in the field of VDs. In this review, the potential of MOFs to act as biosensors, contrast agents, artificial nanozymes, and multifunctional therapeutic agents in the diagnosis and treatment of VDs from the clinical perspective, highlighting the integration between clinical methods with MOFs is generalized. At the same time, multidisciplinary cooperation from chemistry, physics, biology, and medicine to promote the substantial commercial transformation of MOFs in tackling VDs is called for.

Mussel-Mimetic Hydrogel Coating with Anticoagulant and Antiinflammatory Properties on a Poly(lactic acid) Vascular Stent

Biodegradable stents are the most promising alternatives for the treatment of cardiovascular disease nowadays, and the strategy of preparing functional coatings on the surface is highly anticipated for addressing adverse effects such as in-stent restenosis and stent thrombosis. Yet, inadequate mechanical stability and biomultifunctionality limit their clinical application. In this study, we developed a multicross-linking hydrogel on the polylactic acid substrates by dip coating that boasts impressive antithrombotic ability, antibacterial capability, mechanical stability, and self-healing ability. Gelatin methacryloyl, carboxymethyl chitosan, and oxidized sodium alginate construct a double-cross-linking hydrogel through the dynamic Schiff base chemical and in situ blue initiation reaction. Inspired by the adhesion mechanism employed by mussels, a triple-cross-linked hydrogel is formed with the addition of tannic acid to increase the adhesion and antibiofouling properties. The strength and hydrophilicity of hydrogel coating are regulated by changing the composition ratio and cross-linking degree. It has been demonstrated in tests in vitro that the hydrogel coating significantly reduces the adhesion of proteins, MC3T3-E1 cells, platelets, and bacteria by 85% and minimizes the formation of blood clots. The hydrogel coating also exhibits excellent antimicrobial in vitro and antiinflammatory properties in vivo, indicating its potential value in vascular intervention and other biomedical fields.

Diabetic conditions promote drug coating degradation but prevent endothelial coverage after stenting

The endothelialization of drug-eluting stents is delayed after implantation in patients with diabetes. Although numerous factors were implicated in hyperglycemia-induced endothelial dysfunction, the effects of stent drug coating degradation on endothelial dysfunction remains unclear. We hypothesized that diabetic conditions promote drugcoating degradation and enhance antiproliferative agent release, but that the rapid release of these antiproliferative agents inhibits endothelial cell proliferation leading to poor reendothelialization post-stenting. To verify this hypothesis, a dynamic hyperglycemic circulation system was introduced to measure the profile of drugcoating degradation in vitro. Flow cytometry and RNA sequencing were performed to evaluate endothelial cell proliferation. Moreover, a Type 1 diabetic rabbit model was generated and a rescue experiment conducted to evaluate the effects of rapid drugcoating elution on endothelial coverage in vivo. The main findings were as follows: 1) diabetic conditions promoted drugcoating degradation and increased antiproliferative agent release; 2) this increase in antiproliferative agent release inhibited endothelial cell proliferation and delayed endothelial coverage; and 3) strict glycemic control attenuated drugcoating degradation and promoted endothelial coverage post-stenting. This is the first study to illustrate rapid drugcoating degradation and its potential effects on endothelial recovery under diabetic conditions, highlighting the importance of strict glycemic management in patients with diabetes after drug-eluting stent implantation. STATEMENT OF SIGNIFICANCE: Diabetic conditions promote drug coating degradation and increase the release of antiproliferative agents. Rapid drug coating degradation under diabetic conditions inhibits endothelial cell proliferation and delays endothelialization. Strict glycemic control attenuates drug coating degradation and promotes endothelialization.