About a quarter of individuals with diabetes develop painful foot ulcers, diabetic wounds that are slow to heal both due to the low oxygen content in the wound and due to impaired blood vessels and increased inflammation. These injuries can become chronic, leading to poor quality of life and potential lower limb amputation.
Jianjun Guan, professor of mechanical engineering and materials science at the McKelvey School of Engineering at Washington University in St. Louis, has developed a hydrogel that provides oxygen to alkmke diabetic wounds, reduces inflammation and helps reshape tissue and accelerate healing. Ya Guan, researcher, and Hong Niu, postdoctoral research associate, both in Guan’s lab, are co-first authors.
THE results of the work are published in the scientific journal Science Advances.
Diabetic wounds: this is how the hydrogel works
Guan hydrogel supplies oxygen to the wound using microspheres that gradually release oxygen to interact with cells through an enzyme on their surface that converts what’s inside the bead into oxygen. Oxygen is delivered to the wound for about two weeks and inflammation and swelling subside, promoting healing.
“Oxygen has two roles: one, to improve the survival of skin cells in low oxygen conditions of the diabetic wound; and two, oxygen can stimulate skin cells to produce growth factors necessary for wound repair “, Guan explained.
The tissues of the body require oxygen to survive and they need it even more when the tissues are damaged. Although there are several existing treatments for chronic wounds in people with diabetes, the most common treatment consists of dozens of sessions in a hyperbaric oxygen chamber, but its effectiveness is inconsistent and includes the risk of oxygen toxicity.
In mice, wounds treated with the hydrogel containing the oxygen-releasing microspheres had a higher closure rate than wounds treated with the gel alone or those without treatment. By day 16, hydrogel-treated wounds had reduced to 10.7%. Those treated with the gel alone were reduced to 30.4% and those without treatment were reduced to 52.2%.
Additionally, diabetic wounds treated with the hydrogel containing the oxygen-releasing microspheres had the thickest epidermis on day 8, but thinnest by day 16, indicating that the wound was healing and inflammation was reduced.
Over the past 14 years, Guan has developed this type of gel, which has nearly 70 different chemical functions and structures.
“THEThe gel is a liquid that is first inserted into the subcutaneous tissue, so it is easy to mix into the microspheres“, Specified the expert. “Once we put the mixture of gel and microspheres into diabetic wounds, it becomes a solid because it is temperature sensitive: at lower temperatures it is a liquid and at body temperature it is a solid.”
One risk of providing oxygen to diabetic wounds is providing too much of it, which it creates reactive oxygen species (ROS), which can damage or kill cells at high levels. Guan hydrogel is able to eliminate the ROS content and destroy it, eliminating any risk.
Subsequently, the Guan’s team plans to use the hydrogel in a large animal model with the expectation of future human clinical trials.
“This represents a new therapeutic approach to accelerate the healing of chronic diabetic wounds without drugs”, Guan concluded. “It also has the potential to treat other diseases where oxygen is low, such as peripheral artery disease and coronary artery disease.“.THE
In Italy, assistance in the treatment of diabetic foot and diabetic injuries is among the best in the world and consequently, the number of amputations is the largest compared to that of other countries in the world. Immediately after Italy there are Korea and Luxembourg. According to the OECD (Organization for Economic Cooperation and Development), lower limb amputations are in sharp decline worldwide. According to the OECD: “there was a 30.6% reduction in the number of major amputations. 11 countries also provided data on the number of minor amputations and also in this case, a reduction of about 30% (29.8%) was recorded in the time period of observation ”.