Why have many researching arthroplasty flanked human studies? A team of researchers at the Massachusetts Institute of Technology believes that the problem lies in the drug’s short half-life in the sick leader. So they decided to design a material that could help drugs penetrate deeper into cartilage generating tissues, and they have returned with promising animal results.
The MIT engineers thought that many drugs were washed away from the joint before they even reached chondrocytes, which are cells that produce cartilage. They designed a round-shaped “nanocarrier” to overcome this barrier. The molecule contains many branch-like structures called dendrimers, which are positively charged at their tips. It allows them to bind to the negatively charged cartilage for diffusion, the team explained in the journal Science Translational Medicine.
In order to help the molecules move deeper into the tissue, researchers employed a water-loving polymer called PEG that could partially cover the positive charge as they move. In this manner, the charged molecules can short-circuit from the cartilage and deeper into diseased tissues.
“We found an optimal charging range so that the material can both bind the tissue and bind to further diffusion and not be so strong that it just sticks to the surface,” says Brett Geiger, paper-leading author, in a statement.
The dendrimeral nanopartikelen is the only vehicle, but needs an active therapeutic as a passenger. In its study, MIT researchers used an experimental drug called insulin-like growth factor 1 (IGF-1), which is a protein that stimulates the growth of many tissues, including cartilage.
In rat models of osteoarthritis, researchers found that nanocarrier-bound IGF-1 had a half-life of approximately four days, which is 10 times longer than IGF-1 alone. Furthermore, the concentration of drug remained in the rodent’s knee joint high enough to give a therapeutic effect for about 30 days, the team reported. What was translated to bee tore cartilage recovery, and decreases in joint inflammation and bone pores, compared to IGF-1 alone, said the team.
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MIT researchers hope that their technology can ever be used to improve arthritis treatment that addresses the underlying cartilage problem. So to further prove the benefits of their methodology, researchers have moved to large animal models. The tested combination particle of cows, having a cartilage similar to the thickness of the human being, observed that the drug could penetrate into cartilage in two days.
“It’s a very difficult thing to do. Drugs will usually be cleaned before they can move much of the cartilage,” says Geiger. “When you start thinking about translating this technique from studies on rats to larger animals and in Today people, this technique depends on its success due to its ability to work in thicker cartilage. “
At present, the material is developing to treat osteoarthritis caused by traumatic injury, but scientists believe that it could also be used in the older age-related indication. And they plan to pair the carrier with other drugs, such as those that block inflammatory cytokines, DNA or RNA.