Researchers develop new strategy involving nitric oxide for treating rheumatoid arthritis

KOREA: In breakthrough research, a team of researchers from Korea developed a nitric oxide (NO)-scavenging hydrogel for the treatment of rheumatoid arthritis -- a chronic inflammatory disorder that affects many joints, including those in the hands and feet. It occurs due to the overproduction of NO in the body. The results are published in the online publication of Nano Letters, an international journal in Nanoscience.

NO is used for the prevention of artery plaque build-up in the body and high blood pressure. However, it can cause serious inflammatory diseases such as rheumatoid arthritis, Crohn's disease, and systemic lupus erythematosus.

A team of researchers consisting of Prof. Won Jong Kim and colleagues utilized NO-cleavable-crosslinker that reacts to NO and developed a NO-scavenging nano-sized hydrogel (NO-Scv gel). Earlier, they had tested this hydrogel on animal successfully and confirmed that it is better than the currently used therapeutic drugs. The team had consistently studied on a new way to treat rheumatoid arthritis by scavenging NO and reducing its concentration in the disease site of the body.

As a result of their continuous efforts they successfully developed a NO-responsive macro-sized hydrogel by integrating NO-cleavable crosslinker (NOCCL) in 2017. And now, they took one step further and upgraded it to the current model, NO-scavenging nano-sized hydrogel (NO-Scv gel) which consumes NO through reacting with NO.

This hydrogel is prepared by polymerization between acrylamide and NOCCL. It is different from the former drug, which suppresses NO by an interaction between gene and enzyme, in that it is directly involved in scavenging NO and minimizes side effects. Also, it has more advantage that it can be applied not only to rheumatoid arthritis but also to other NO-mediated inflammatory diseases widely.

The animal test with a mouse proved that this hydrogel is better than dexamethasone, a commercial drug, in suppressing the onset of rheumatoid arthritis effectively.

"The drugs that have been used for suppressing NO affect biomolecules in the body directly and this brings various side effects such as insulin resistance and cardiovascular disease. But, this nano-sized hydrogel has demonstrated many meaningful results that it is more effective in treating rheumatoid arthritis by scavenging NO directly and has decreased the possibility of the side effects caused by the current drugs that we use today," commented Prof. Kim.