Micro-rockets against arthritis
Rheumatoid arthritis is a chronic inflammatory disease characterized by pain, swelling and joint damage. Despite the fact that there are medications that can slow down the destruction of joints and relieve pain (steroids, anti-inflammatory drugs, immunosuppressants), their side effects and insufficient effectiveness do not allow to cure rheumatoid arthritis. In a new study conducted with the support of the National Foundation of Natural Sciences of China, magnesium-based micromotors were developed, driven by hydrogen bubbles, which reduced the symptoms of rheumatoid arthritis in rats with intra-articular injection.
Scientists associate the development of rheumatoid arthritis with the excessive production of reactive oxygen species, which can oxidize and destroy cartilage and bones, as well as enhance the expression of pro-inflammatory cytokines. Hydrogen gas therapy can neutralize reactive oxygen species and reduce the level of proinflammatory cytokines when administered to patients alimentally – with drinking water. However, hydrogen is poorly soluble in body fluids and is rapidly excreted by oral administration, which limits its therapeutic effect. Fei Peng, Infeng Tu, Yingjia Li and colleagues wanted to find a way to produce and deliver hydrogen gas directly to the inflamed joint.
The researchers founded their own system of magnesium micromotors – microscopic spheres that react with water to form hydrogen bubbles that drive the motors. They coated the micromotors with hyaluronic acid, leaving a small area free for magnesium to interact with water. When placed in a simulated articular fluid, the micromotors were able to move independently and demonstrated a long, steady release of hydrogen bubbles.
After that, the researchers tested their development on animal models by inserting micromotors into the joint cavity of rats with rheumatoid arthritis and using ultrasound to visualize them. By absorbing reactive oxygen species and reducing inflammation with the help of active hydrogen, micromotors relieved oxidative stress and reduced the level of pro-inflammatory cytokines. Compared to rats that were not injected, the treated rats had less pronounced paw swelling, less bone erosion, and lower levels of proinflammatory cytokines.
Micromotors need clinical studies in humans, but already they have shown great potential for the treatment of rheumatoid arthritis and other inflammatory diseases.
Article by C.Xu et al. Magnesium-Based Micromotors as Hydrogen Generators for Precise Rheumatoid Arthritis Therapy is published in the journal Nano Letters.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on ACS materials: Treating rheumatoid arthritis with micromotors.