New hydrogel for myocardial repair

The Darned Heart
Scientists have developed an artificial heart muscle Artem Astashenkov, "Russian Planet"

Scientists have presented artificial tissues of the heart muscle. Made on the basis of a fundamentally new hydrogel, they are able to contract not only in laboratory conditions, but also when transplanted into the heart of an experimental animal. The development was presented at the 247th National Convention and Exhibition of the American Chemical Society, held in Texas on March 16-20 (Building heart tissue that beat).

Hydrogels are a common name for a class of polymer substances saturated with water. Usually they are flexible like the tissues of a living organism and perfectly absorb moisture. Depending on the chemical composition, there are many applications of hydrogels: the production of contact lenses, diapers, explosives and glue; cosmetic surgery; treatment of burns; delivery of drugs to the desired subsystem of the body and others.

The similarity of hydrogels to biological tissues has long attracted the attention of researchers working on the regeneration of damaged and the creation of artificial organs. Artificial skin already exists and is actively used; scientists are working on substitutes for cartilage, muscles and the cornea of the eye. In all these cases, hydrogels act as a "building" framework.

Harvard Medical School researchers Nazim Annabi and Ali Khademhoseini and their colleagues from Brigham Hospital and the University of Sydney set out to adapt hydrogel technology for the production of tissues that could "patch up" a damaged heart. This task is much more difficult than the manufacture of artificial leather: the heart tissues have a complex three-dimensional structure, and most importantly, they are elastic and resistant to loads caused by contractions during the heartbeat.

Using traditional hydrogels based on natural proteins, scientists were able to accurately adjust the chemical, biological, mechanical and electrical properties of the material to various tissues of the human body, but it was not possible to repeat the elasticity of the heart muscle: the gel crumbled like gelatin.

The breakthrough came when researchers created a new hydrogel based on tropoelastin, a protein found everywhere in the human body. The new gel frame for the implant met all the requirements for use in the regeneration of the heart muscle. Now it was necessary to grow the heart muscle cells themselves on it, which is also a non-trivial task.

Hydrogel for the heart muscle. Photo: biofutur.com

In order for the cellular structure of the "patch" to correspond to the natural one, the laboratory of Khademkhoseini used 3D printing and microengineering technologies. They gave the gel a structure that guided the growth of tissues into the desired shape. As a result, there were many small areas of cardio-muscular tissue in a micro-pattern of guide grooves on an elastic substrate. And most importantly, during the experiments, they were synchronously reduced.

Now Harvard scientists are working on adapting this technology for the production of musculoskeletal muscles, heart valves, blood vessels and skin containing them. In addition, they began testing the "heart patch" on large animals.

Cardio-muscular tissues are prone to serious injuries as a result of heart attacks and other similar incidents. The usual solution in such a situation is a complete heart transplant, but not everyone has enough donor organs, and complications, up to rejection, are not excluded. Scientists have been looking for many years for a way to cure the patient's own tissues after a heart attack. The "patches" presented by Harvard researchers can solve this problem.

Portal "Eternal youth" http://vechnayamolodost.ru 20.03.2014