Nanospheres of a Bisphosphonate Attenuate Intimal Hyperplasia
The present study explored a novel strategy for attenuation of restenosis after arterial injury by a bisphosphonate encapsulated in polymeric nanoparticles (NP) for transient selective depletion of macrophages. A bisphosphonate (BP), 2-(2-Aminopyrimidino) ethyldiene-1,1-bisphosphonic acid betaine (ISA), was successfully formulated in 400 nm sized polylactide/glycolide-based NP with high yield (69%) and entrapment efficiency (60% w/w). ISA NP, but not blank NP or free ISA, exhibited specific and significant cytotoxic effect on macrophages-like RAW 264 cells, in a dose-dependent manner, with no inhibitory effect on the growth of smooth muscle cells (SMCs). Fluorescent pyrene-labeled NP were shown to be taken up by RAW 264 cells, but not by SMCs. Intravenously (IV) administered ISA NP (15 mg/kg, single dose on day-1) resulted in a significant attenuation of neointima to media area ratio (N/M) by 40% and stenosis by 45% 14 days after rat carotid injury, in comparison to animals treated with free ISA, buffer or blank NP. However, the effect was not preserved 30 days post injury, and an insignificant reduction of neointimal formation was observed. Neointimal hyperplasia was also significantly suppressed after subcutaneous (SC) injection of ISA NP (15 mg/kg, single dose on day-1), reducing both N/M and stenosis. Intraperitoneal (IP) injection of silica, a known selective toxin for macrophages, (1000 mg/kg), also resulted in a significant inhibition of N/M and stenosis, which further reinforces the cause-effect relationship of macrophage-inactivation and the prevention of neointima formation. Biocompatible and biodegradable NP loaded with ISA characterized by high colloidal stability, reproducible activity, and high drug entrapment warrant further consideration for restenosis therapy, and may be useful in other disease processes involving monocytes/macrophages.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Publication date: 2006-09-01
More about this publication?
- Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites