Yale researchers describe a breakthrough in safe and effective administration of potential antiviral drugs - small interfering RNA (siRNA) molecules that silence genes - the first step in development of a new kind of treatment for sexually transmitted diseases (STDs). The work is reported May 4 as an advance online publication of Nature Materials.
"RNA interference is a promising approach for prevention and treatment of human disease," said lead author Kim Woodrow, Yale postdoctoral fellow in Yale's School of Engineering & Applied Science. "We wanted to develop a new strategy of delivering siRNAs with a FDA-approved material."
As their name suggests, siRNAs interfere and knock out the function of genes in higher organism as well as in microbes that may cause STDs. The researchers designed siRNAs to target a gene expressed widely in the lining of the female mouse reproductive tract, in this proof-of-principle work.
Using densely-loaded nanoparticles made of a biodegradable polymer known as PLGA, the researchers created a stable "time release" vehicle for delivery of siRNAs to sensitive mucosal tissue like that of the female reproductive system.
They found that the particles, loaded with the drug agent, moved effectively in two important ways, penetrating to reach cells below the surface of the mucosa and distributing throughout the vaginal, cervical, and uterine regions. Furthermore, the siRNAs stayed in the tissues for at least a week and knockdown of gene activity lasted up to 14 days.