Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Battle of the Blood Clots

11.10.2013
Tailored glycopolymers as anticoagulant heparin mimetics

One of the risks of any large operation is the occurrence of blood clots. To prevent this, patients are routinely given the anticoagulant heparin or related drugs. American scientists have now introduced a new approach to the production of synthetic heparin mimetics with better activity profiles.



Heparin has been used as an anticoagulant since 1935 to both treat and prevent the deep vein thrombosis that can result from operations, blood transfusions, or dialysis. Heparin is a substance produced by the body and consists of long chains of sugar (saccharide) molecules. The sugar building blocks contain a large number of sulfate groups.

Because heparin is obtained from animal tissues, its use does pose some problems. Contamination may lead to health risks. Furthermore, batches of the drug are often not homogeneous so the effectiveness of a given dose must be calculated case by case. In about 3 % of patients, long-term treatment with heparin leads to a dangerous autoimmune disease.

Low-molecular-weight drugs such as Arixtra, which contains only five sugar groups, have been developed as an alternative. Their disadvantage is the very complex and expensive process used to make them.

Linda C. Hsieh-Wilson and her team at the California Institute of Technology in Pasadena have now uncovered an interesting new angle: synthetic glycopolymers, long chains of molecules that have sugar molecules as side groups. The researchers chose to use two sugars typically found in heparin as side groups.

One of these sugars was equipped with an additional sulfate group. The synthesis of such glycopolymers is much simpler than the synthesis of natural polysaccharides, but it is still a complex undertaking, and it is made more difficult in this case because of the need to attach sulfate groups in a controlled fashion. The team was able to use a ring-opening metathesis polymerization reaction (ROMP) to make polymer chains of varying length with a maximum of 45 units.

The longer molecular chains demonstrate stronger activity than anticoagulants currently in clinical use. The additional sulfate group is critical to this effectiveness. Interestingly, systematic changes to the length of the chain and pattern of sulfate groups allow for fine-tuning of the anticoagulant effect. This makes it possible to make drugs with different activities from those previously in clinical use. For example, the glycopolymer containing 45 building blocks targeted the two major branches of the blood coagulation cascade to a different extent than both the small molecule and heparin polysaccharide drugs.

About the Author
Dr. Linda Hsieh-Wilson is a Professor of Chemistry at the California Institute of Technology and an Investigator at the Howard Hughes Medical Institute. Her research focuses on the application of organic chemistry to probe the roles of carbohydrates and protein glysosylation in neurobiology and cancer, and has been recognized by multiple awards.
Author: Linda C. Hsieh-Wilson, California Institute of Technology, Pasadena (USA), http://chemistry.caltech.edu/~fucose/contact.html
Title: Tailored Glycopolymers as Anticoagulant Heparin Mimetics
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201306968

Linda C. Hsieh-Wilson | Angewandte Chemie
Further information:
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht Modern genetic sequencing tools give clearer picture of how corals are related
17.08.2017 | University of Washington

nachricht The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Gold shines through properties of nano biosensors

17.08.2017 | Physics and Astronomy

Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter

17.08.2017 | Earth Sciences

Mars 2020 mission to use smart methods to seek signs of past life

17.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>