Tablets of the future: nanoparticles
Pills with nanoparticles are replacing injections
That is why researchers led by Robert Langer from the Massachusetts Institute of Technology (USA) have developed a new type of nanoparticle that can be taken orally (swallowed), followed by entry into the body through the digestive tract – as in the case of conventional medicine.
How is it done and works? Scientists used a coating of components of the neonatal Fc receptor, a protein that allows infants to absorb IgG antibodies from mother's milk, which are sorely lacking in the newborn's immune system. Normally, an adult has a normal Fc receptor that does not pass other people's antibodies. Using a coating of "neonatal" Fc proteins for their nanoparticles, scientists simply "deceived" the cells of the intestinal walls by offering nanoparticles of biocompatible polymers (block copolymers of polylactic acid and polyethylene glycol) to the body as antibodies from mother's milk, and doing this in an adult body that has not assimilated mother's milk for a long time.
As a result, the probability of overcoming the intestinal wall for nanoparticles increased by 11 times and reached a level at which oral insulin intake allowed the experimental mouse to reduce blood sugar levels as effectively as if it were a habitual injection.
The experience turned out to be successful, but, as the developers emphasize, insulin is just the tip of the iceberg. Yes, the possibility of administering such a drug without injections and the loss of effectiveness that often accompanies oral administration is an absolute blessing, since injections, of course, are much less convenient. However, new nanoparticles can make life easier in other cases, when conventional methods, in principle, do not cope. So, with a high level of cholesterol in the blood or arthritis, it is not always possible to convince a patient to regularly visit a doctor who would make appropriate injections, and such patients often simply do not have such opportunities. "If you are a patient and have a choice, then it will most likely be made in favor of medications that can be taken orally," Mr. Langer reasonably observes.
In addition, several drugs are being clinically tested at once, packaged in nanocapsules and capable of carrying components of cancer chemotherapy or even small interfering RNAs that can turn off selected genes in tumor cells (which can also be useful in anti-cancer therapy). Usually, the tumor is surrounded by "flowing" blood vessels, through which nanoparticles deliver their cargo to "sick" cells, without releasing unsafe substances in healthy areas of the body. This makes it possible to radically reduce the side effects of chemotherapy, which often repel patients from this treatment option.
The introduction of nanoparticles carrying insulin and anti–cancer drugs continues, but the developers have already thought about nanocarriers that could overcome an even tougher barrier - the hemoencephalic barrier that separates the contents of blood from brain cells and is one of the main obstacles to the delivery of drugs to the brain.
The study report is published in the journal Science Translational Medicine (Pridgen et al., Transepithelial Transport of Fc-Targeted Nanoparticles by the Neonatal Fc Receptor for Oral Delivery).
Prepared based on the materials of MIT News – Pills of the future: nanoparticlesPortal "Eternal youth" http://vechnayamolodost.ru