Apr 28 2020
Existing treatments for rheumatoid arthritis help reduce the symptoms, but they usually lead to severe side effects. The findings of a novel mouse study indicate that a new light-activated drug delivery technique enables the treatments to be restricted to the joints, which could decrease the side effects to the whole body.
A new light-activated drug delivery method could help confine arthritis treatments to the joints, greatly reducing side effects. The drug is activated using an external, low-power laser shown here with a person’s finger. Image Credit: Victoria Wickenheisser.
At present, in the United States, 1.3 million people are diagnosed with rheumatoid arthritis. It is a chronic disease that results in painful joint swelling that can ultimately lead to joint deformities and bone loss.
Our delivery system decreased arthritis in our experimental model while carrying and delivering much lower quantities of drug than is required for currently approved treatment.
Emilia Zywot, Doctoral Candidate, University of North Carolina, Chapel Hill
Zywot is also a member of the group that designed the latest drug delivery method.
Ms Zywot was about to present this study at the American Society for Pharmacology and Experimental Therapeutics annual meeting in San Diego this month to be held together with the 2020 Experimental Biology conference. However, it was canceled due to the outbreak of COVID-19. The abstract of the researchers has now been published in this month’s issue of The FASEB Journal.
The latest delivery method involves attaching a drug to vitamin B12 molecules designed to react to low levels of laser light. Then, the process of transfusion is employed to administer red blood cells loaded with the vitamin B12 molecules into mice, where the cells circulate until being triggered.
The drug gets activated only in regions receiving a low level of long-wavelength laser light, which can be provided from the exterior part of the body. This controllable activation enables a high concentration of the drug to be discharged at the spot of inflammation. Thus, it requires lower whole-body, or systemic, quantities of the drug for effective treatment.
The scientists tested their latest technique by administering dexamethasone, an arthritis drug, to arthritic mice through the light-based delivery system and conventional injections.
By using laser light, the light-responsive drug in an arthritic paw was stimulated. The light-based delivery system was found to reduce arthritis with a three-fold lower dose of dexamethasone.
We hope that our drug delivery platform will better control drug delivery and decrease the amount of systemic exposure and off-target effect. We envision that it will be useful for any drug that can be synthetically attached to our light-responsive system, making it amenable to applications beyond arthritis.
Emilia Zywot, Doctoral Candidate, University of North Carolina, Chapel Hill
Furthermore, the scientists intend to analyze the light-responsive drug delivery system in mouse models of arthritis to gain better insights into the potential of the latest system in comparison with existing treatments.
Source: https://experimentalbiology.org