Abstract |
Bioabsorbable drug-eluting stents (BDES) offer multiple advantages over a permanent bare metal stent (BMS) for coronary artery disease (CAD). However, current BDES remains two major issues: inferior radial strength and biocompatibility. PowerStent Absorb BDES, fabricated by co-formulating amorphous calcium phosphate (ACP) nanoparticles with poly-L-lactic acid (PLLA/ACP, 98/2, w/w) and 2% Paclitaxel (PAX, w/w) was designed to address these issues. Two cohorts of 6 miniature pigs were each implanted with PLLA/PAX (control, 2% PAX, w/w) or PowerStent Absorb BDES. After 1 month in-vivo study, histological analyses showed significantly reduced restenosis in the PowerStent Absorb BDES cohort relative to the control cohort (44.49 +/- 410.49% vs. 64.47 +/- 16.2%, p < 0.05). Stent recoil (21.57 +/- 5.36% vs. 33.81 +/- 11.49, P < 0.05) and inflammation (3.01 +/- 0.62 vs. 4.07 +/- 0.86, P < 0.01) were also obviously decreased. From in-vitro studies, PLLA/ACP/PAX stent tube maintained significantly greater radial strength than control group during 6 months in-vitro degradation (PLLA/ACP/PAX vs. PLLA/PAX: before hydrolysis: 82.4 +/- 1.9 N vs.74.8 +/- 3.8 N; 6 weeks: 73.9 +/- 1.8 N vs. 68.0 +/- 5.3 N; 3 months: 73.5 +/- 3.4 N vs.67.2 +/- 3.8 N; 6 months: 56.3 +/- 8.1 N vs. 57.5 +/- 4.9 N). Moreover, ACP facilitated the hydrolytic degradation of PLLA compared with control one (62.6% vs. 49.8%), meanwhile, it also increased the crystallinity of PLLA (58.4% vs. 50.7%) at 6 months. From SEM observations, ACP created nanometer pores that enlarge gradually to a micrometer scale as degradation proceeds. The changes of the porosity may result in greatly promoting re-endothelialization.
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Authors | Zhiyuan Lan, Yongnan Lyu, Jianmin Xiao, Xiaoxin Zheng, Suyuan He, Gaoke Feng, Yipei Zhang, Shihang Wang, Edward Kislauskis, Jiuhao Chen, Stephen McCarthy, Roger Laham, Xuejun Jiang, Tim Wu |
Journal | Journal of biomedical nanotechnology
(J Biomed Nanotechnol)
Vol. 10
Issue 7
Pg. 1194-204
(Jul 2014)
ISSN: 1550-7033 [Print] United States |
PMID | 24804540
(Publication Type: Journal Article, Research Support, N.I.H., Extramural)
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Chemical References |
- Biocompatible Materials
- Calcium Phosphates
- Polyesters
- Polymers
- amorphous calcium phosphate
- Lactic Acid
- poly(lactide)
- Paclitaxel
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Topics |
- Animals
- Biocompatible Materials
(chemistry)
- Calcium Phosphates
(chemistry)
- Calorimetry, Differential Scanning
- Coronary Artery Disease
(diagnostic imaging, pathology, physiopathology, therapy)
- Coronary Vessels
(drug effects, pathology, physiopathology)
- Drug-Eluting Stents
- Female
- Lactic Acid
(chemistry)
- Male
- Materials Testing
- Nanoparticles
(chemistry, ultrastructure)
- Paclitaxel
(pharmacology)
- Polyesters
- Polymers
(chemistry)
- Radiography
- Swine
- Swine, Miniature
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