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nanoparticles to treat blood clots

Posted: Sat Jul 07, 2012 2:52 pm
by Cece
http://www.sciencemag.org/content/early ... 5.abstract
Shear-Activated Nanotherapeutics for Drug Targeting to Obstructed Blood Vessels

Abstract

Obstruction of critical blood vessels due to thrombosis or embolism is a leading cause of death world-wide. Here, we describe a biomimetic strategy that uses high shear stress caused by vascular narrowing as a targeting mechanism – in the same way platelets do–to deliver drugs to obstructed blood vessels. Microscale aggregates of nanoparticles were fabricated to break up into nanoscale components when exposed to abnormally high fluid shear stress. When coated with tissue plasminogen activator and administered intravenously in mice, these shear-activated nanotherapeutics induce rapid clot dissolution in a mesenteric injury model, restore normal flow dynamics, and increase survival in an otherwise fatal mouse pulmonary embolism model. This biophysical strategy for drug targeting, which lowers required doses and minimizes side effects while maximizing drug efficacy, offers a potential new approach for treatment of life-threatening diseases that result from acute vascular occlusion.
Brilliant research that is still in the animal research stages but could move on to human studies. Remember the patient in Costa Rica whose stent had clotted who passed away from internal bleeding due to a clot-busting drug. tPA that is in these nanoparticles is a clot-busting drug. If it can be delivered directly to the clot by the nanoparticles that target the high shear stress, this could prevent internal bleeding such as that which led to the Canadian patient's death. CCSVI IRs are not using tPA to treat clots in jugular veins most likely because of risks such as these; instead they are conservatively monitoring the clot while placing the patient on anticoagulants to prevent the clot from worsening or they are attempting manual clot removal which requires a repeat catheter venogram procedure. If something like these nanoparticles can make it to market, this would open up another way to treat clots. CCSVI IRs are also attempting to prevent clots by prescribing anticoagulation such as Pradaxa.

Re: nanoparticles to treat blood clots

Posted: Sat Jul 07, 2012 3:20 pm
by Cece
to jump from this to another idea that is even further out there
http://www.sciencedaily.com/releases/20 ... 164416.htm
Now a new research report appearing online in the FASEB Journal offers a new strategy to reduce or eliminate scars on the skin. Specifically, scientists from NYU describe how agents that block receptors for adenosine (a molecule generated from ATP which is used by the body to provide energy to muscles) can be applied topically to healing wounds to reduce scar size, yielding skin that feels more like the original, unscarred skin.
Could this also apply to scarring not on skin but in blood vessels?
What about putting adenosine in the nanoparticles, where it would target areas of high shear stress in veins scarred by ccsvi treatment, and contribute to the healing of that scarring?
I don't know if adenosine could do this but if it hasn't been investigated, we don't know that it won't.

Another idea is if nanoparticles could target areas of LOW shear stress. Our blood brain barrier may be weakened due to low shear stress due to slow flow due to blocked jugulars. When CCSVI cannot be 100% resolved, this low shear stress may remain. What drug could be targeted to be released in this area of low shear stress, with what results?

It is interesting watching science fiction become reality.

Re: nanoparticles to treat blood clots

Posted: Sun Jul 08, 2012 10:53 pm
by NHE
Cece wrote:to jump from this to another idea that is even further out there
http://www.sciencedaily.com/releases/20 ... 164416.htm
Now a new research report appearing online in the FASEB Journal offers a new strategy to reduce or eliminate scars on the skin. Specifically, scientists from NYU describe how agents that block receptors for adenosine (a molecule generated from ATP which is used by the body to provide energy to muscles) can be applied topically to healing wounds to reduce scar size, yielding skin that feels more like the original, unscarred skin.
Could this also apply to scarring not on skin but in blood vessels?
What about putting adenosine in the nanoparticles, where it would target areas of high shear stress in veins scarred by ccsvi treatment, and contribute to the healing of that scarring?
The text you quoted states that they are blocking adenosine. Nanoparticles with adenosine would likely make things worse.


NHE

Re: nanoparticles to treat blood clots

Posted: Mon Jul 09, 2012 9:07 am
by Cece
ohhhh good point NHE

Avoid blood clots

Posted: Mon Jul 16, 2012 3:38 am
by MarkW
Hello Cece,
My recommendation to everyone undergoing or offering 'percutaneous venoplasty' is to avoid getting thromboses. A long time ago I said that everyone should compile a family medical history to discover if they are at an increased risk of thromboses. If yes then the IR/Vascular Surgeon should conduct a clotting screen of that patient and prescribe appropriate medication. A standard medication regime is not sufficient for a small group of people after balloon venoplasty for CCSVI syndrome. It seems timely to repeat this advice for anyone considering therapy for CCSVI syndrome.
Interesting research on nanoparticles but prevention of thromboses is far better than treating them!!
Kind regards,
MarkW
Cece wrote:http://www.sciencemag.org/content/early ... 5.abstract
Shear-Activated Nanotherapeutics for Drug Targeting to Obstructed Blood Vessels
Abstract
Obstruction of critical blood vessels due to thrombosis or embolism is a leading cause of death world-wide...........
Brilliant research that is still in the animal research stages but could move on to human studies. Remember the patient in Costa Rica whose stent had clotted who passed away from internal bleeding due to a clot-busting drug. tPA that is in these nanoparticles is a clot-busting drug. If it can be delivered directly to the clot by the nanoparticles that target the high shear stress, this could prevent internal bleeding such as that which led to the Canadian patient's death. CCSVI IRs are not using tPA to treat clots in jugular veins most likely because of risks such as these; instead they are conservatively monitoring the clot while placing the patient on anticoagulants to prevent the clot from worsening or they are attempting manual clot removal which requires a repeat catheter venogram procedure. If something like these nanoparticles can make it to market, this would open up another way to treat clots. CCSVI IRs are also attempting to prevent clots by prescribing anticoagulation such as Pradaxa.

Re: nanoparticles to treat blood clots

Posted: Mon Jul 16, 2012 10:47 am
by Cece
I agree completely, MarkW.
This nanoparticle research is 'out there' and not immediately applicable for us.
Most doctors prescribe an anticoagulant after the procedure, which may reduce but not eliminate the possibility of clotting, although research is lacking in this area.