Very small fibers loaded with curcumin, a compound found in the turmeric plant, successfully eased inflammation and lessened the size of endometriosis lesions in a mouse model of the disease.

These nanofibers, a nanotechnology-based system, could be used to deliver endometriosis medications directly to affected tissue in a sustained and prolonged manner, researchers suggest.

Their study, “Curcumin-loaded nanofibers for targeting endometriosis in the peritoneum of a mouse model,” was published in Journal of Materials Science: Materials in Medicine.

As many as half of all who undergo surgery for endometriosis, the gold standard for treating this condition, experience a recurrence within five years. A need exists for additional therapeutic approaches, including a more effective way of administering medications to prevent and treat such recurrences.

One of the problems with a pharmaceutical therapy is that it needs to get to a certain place in the body in order to have its intended effect — in this case, the uterus and surrounding tissue. Moreover, it must remain in that place long enough to work, and without causing unintended effects elsewhere.

“Thus, it is logical to design a drug delivery system that controls sustained and prolonged release of an anti-endometriosis agent in the peritoneum and pelvic cavity,” the researchers wrote.

These scientists designed such a system using nanofibers (very small and thin fibers), coated with an anti-endometriosis agent. The fibers are implanted in the body, and over time, the agent falls off the fibers and is released. The fibers themselves are designed not to provoke inflammation, and so can be delivered with a reasonable expectation of safety.

“This is the first time that drug-loaded nanofibers, as an implantable drug delivery system, have been used to target endometriosis in the peritoneum,” the researchers said.

They used curcumin to load these nanofibers, a component of turmeric that has established anti-inflammatory properties, and has also been used for its anticancer and anti-oxidant effects. Curcumin has shown efficacy in mouse models of endometriosis, where it is often given via injection directly into the pelvic cavity.

“But the problem is that the bioavailability of curcumin is modest because of its poor absorption, low water solubility, rapid metabolism and systemic elimination,” the researchers wrote. “Therefore the oral administration need daily doses of curcumin and because of recurrent nature of endometriosis, it is necessary to use curcumin daily for a long time, this issue is also considered to the peritoneal administration of curcumin.”

More research is needed to determine the best route of administration for this substance, allowing its prolonged release and the assessment of its full therapeutic potential.

After constructing and characterizing the nanofibers, the researchers implanted them in mice with induced endometriosis.

The fibers initially released curcumin in a ‘burst’ — about 23% of the loaded curcumin was released in the first 30 minutes, and about 35% by the end of the first day. According to the researchers, this was “not unexpected.” After one month, the fibers had released, on average, about half of the loaded curcumin.

This demonstrates a proof-of-concept for using the system to continually deliver a medicine to affected tissue over time. Additionally, modifications to the makeup of the nanofibers themselves could allow for different patterns of release, which the researchers highlighted as a possible area for future study.

Mice that were treated with curcumin-loaded nanofibers had significantly smaller endometriosis lesions compared to control mice that received no treatment. “After 21 days, the size of the endometriotic lesions and cysts significantly decreased compared to the control group, with no sign of endometriosis features,” the authors stated.

This effect was accompanied by tissue-level changes, such as decreased numbers of inflammatory cells in the endometriotic tissues of treated animals.

These data suggest a significant therapeutic effect of the curcumin-loaded nanofibers, which again supports the utility of the system as a whole. “In this study, we successfully designed a sustained drug delivery system to target endometriosis in the peritoneum of mice,” the scientists wrote.

“The animal model and histological [tissue] evaluations showed that these implantable curcumin loaded nanofibers successfully mitigated intraperitoneal endometriosis,” they concluded.