A new form of 'nanosized' aspirin to overcome 'aspirin resistance'

September 4, 2013
A new form of aspirin to overcome ‘aspirin resistance’
Scientists are developing a new form of aspirin to overcome “aspirin resistance,” which affects millions of people who could otherwise benefit from the drug commonly used to prevent heart attack and stroke. Credit: Photos.com/Thinkstock

Scientists are reporting development of a new form of aspirin—taken daily by about 60 million people in the United States alone to reduce the risk of heart attack and stroke—that could extend aspirin's benefits to people who may not respond to the drug. Their advance toward coping with "aspirin resistance" appears in the journal ACS Nano.

Shiqi Peng, Ming Zhao and colleagues note that aspirin lowers by keeping called platelets from clumping and forming clots. But some experts believe that aspirin doesn't work for millions of people, who may switch to more costly, potent with more serious side effects. Scientists have tried to address aspirin resistance by combining it with other drugs. But Peng and Zhao say that the problem remains. Their research group decided to modify aspirin in an effort to make it work for more people.

They linked aspirin to a carrier consisting of a fragment of protein that can transport aspirin directly to damaged parts of blood vessels where clots form. Experiments with , stand-ins for humans in such early tests, showed that the carrier delivered aspirin to areas of blood vessels where clots were forming. It released aspirin inside the developing clot and stopped the clot-formation process.

A new form of aspirin to overcome 'aspirin resistance'

The article is titled "Nano-Sized Aspirin-Arg-Gly-Asp-Val: Delivery of Aspirin to Thrombus by the Target Carrier Arg-Gly-Asp-Val Tetrapeptide."

Explore further: Aspirin resistant proteins are identified

More information: Nanosized Aspirin-Arg-Gly-Asp-Val: Delivery of Aspirin to Thrombus by the Target Carrier Arg-Gly-Asp-Val Tetrapeptide, ACS Nano, Article ASAP. DOI: 10.1021/nn402171v

Abstract
Resistance and nonresponse to aspirin dramatically decreases its therapeutic efficacy. To overcome this issue, a small-molecule thrombus-targeting drug delivery system, aspirin-Arg-Gly-Asp-Val (A-RGDV), is developed by covalently linking Arg-Gly-Asp-Val tetrapeptide with aspirin. The 2D ROESY NMR and ESI-MS spectra support a molecular model of an A-RGDV tetramer. Transmission electron microscopy images suggest that the tetramer spontaneously assembles to nanoparticles (ranging from 5 to 50 nm in diameter) in water. Scanning electron microscopy images and atomic force microscopy images indicate that the smaller nanoparticles of A-RGDV further assemble to bigger particles that are stable in rat blood. The delivery investigation implies that in rat blood A-RGDV is able to keep its molecular integrity, while in a thrombus it releases aspirin. The in vitro antiplatelet aggregation assay suggests that A-RGDV selectively inhibits arachidonic acid induced platelet aggregation. The mechanisms of action probably include releasing aspirin, modifying cyclic oxidase, and decreasing the expression of GPIIb/IIIa. The in vivo assay demonstrates that the effective antithrombotic dose of A-RGDV is 16700-fold lower than the nonresponsive dose of aspirin.

Related Stories

Aspirin resistant proteins are identified

June 26, 2007

Spanish scientists have identified blood proteins that might create aspirin resistance that keeps thousands of people from reaping aspirin's benefits.

Recommended for you

Making nanowires from protein and DNA

September 3, 2015

The ability to custom design biological materials such as protein and DNA opens up technological possibilities that were unimaginable just a few decades ago. For example, synthetic structures made of DNA could one day be ...

Graphene made superconductive by doping with lithium atoms

September 2, 2015

(Phys.org)—A team of researchers from Germany and Canada has found a way to make graphene superconductive—by doping it with lithium atoms. In their paper they have uploaded to the preprint server arXiv, the team describes ...

For 2-D boron, it's all about that base

September 2, 2015

Rice University scientists have theoretically determined that the properties of atom-thick sheets of boron depend on where those atoms land.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.