Nanoantioxidants have confirmed their potential
Researchers at Rice University, Baylor College of Medicine and the University of Texas have developed a set of methods that allowed them to evaluate the effectiveness of combined nanoparticles synthesized by them in 2012, consisting of polyethylene glycol (PEG) and hydrophilic carbon clusters and called PEG-HCCs (from the English polyethylene glycol-hydrophilic carbon clusters). The application of the new method demonstrated the ability of nanoparticles to catalyze the neutralization of reactive oxygen species formed in cells in the first minutes and hours after damage and capable of causing irreparable damage to affected tissues.
The width of the PEG-HCC nanoparticle is approximately 3 nanometers, and the length is 30-40 nm. One particle contains 2,000 to 5,000 carbon atoms. The use of a complex of methods, including electron paramagnetic resonance spectroscopy, oxygen electrodes and spectrophotometry, demonstrated the ability of a single nanoparticle to catalyze the transformation of 20,000 to a million molecules of reactive oxygen species per second into molecular oxygen, which damaged tissues need.
At the same time, the nanoparticles had no effect on the nitric oxide molecules necessary to maintain the lumen width of blood vessels, as well as involved in the transmission of nerve signals and cell protection. The efficiency of the nanoparticles remained stable at various levels of acidic environment and did not deteriorate for at least three months.
Previously, the authors demonstrated that the introduction of non-toxic PEG-HCC nanoparticles allows to quickly stabilize blood flow in the brain and protect tissues from the harmful effects of reactive oxygen species, the synthesis of which increases in response to damage, especially with massive blood loss.
Their earlier work was devoted to traumatic brain injuries, in which cells release an excessive amount of so-called superoxides into the bloodstream. The immune system uses these free radicals, which have one unpaired electron, to destroy microorganisms that enter the body. In small concentrations, they contribute to maintaining the normal energy balance of the cell. Under normal conditions, the level of these molecules is controlled by the enzyme superoxide dismutase neutralizing them.
However, the amount of superoxide molecules released even with a small injury is enough to suppress the protective mechanisms of the brain. Moreover, superoxide molecules can transform into other reactive oxygen species, such as peroxynitrite, which can cause further tissue damage.
Based on the results of the latest study, the authors believe that PEG-HCC nanoparticles can be useful not only in the treatment of traumatic brain injuries and stroke, but also in acute injuries to other organs and tissues, as well as during medical procedures, including organ transplantation.
Article by Errol L. G. Samuel et al. Highly efficient conversion of superoxide to oxygen using hydrophilic carbon clusters is published in the journal Proceedings of the National Academy of Sciences.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Rice University:
Nano-antioxidants prove their potential.
17.02.2015