New research from the University’s Chronic Pain Consortium might have fewer doctors asking patients to “Tell me where it hurts” and eventually, allow patients to receive a drug in a precise location—creating fewer side effects and enabling a smaller dose of medication to be effective.
In recently published studies, Dr. Jelena Janjic, assistant professor of pharmaceutics, and Dr. John Pollock, associate professor of biology, developed non-invasive imaging methods that pinpoint where the pain-inducing inflammation originates.
This is a breakthrough for treating pain, Pollock explained, because soreness in one location might actually be caused by a pinched nerve or other event elsewhere. “The process relies on the interplay between the immune system and the nervous system to work,” Pollock said.
To specifically locate immune cells involved in pain, Janjic developed tiny nanodroplets called nanoemulsions. When injected, the droplets accumulate at the inflamed areas. While this procedure has been tested in other uses, the consortium is pioneering its use in pain treatment.
Locating the origin of the pain sets the stage for a different treatment. Janjic has developed a novel way to administer medications directly to the inflamed spot, which could impact people with chronic pain issues, including osteoporosis and arthritis, and could lead to personalized pain treatment.
Now, patients are often prescribed a dosage of drugs, a couple times during the day, over a course of days or weeks, to ease their pain. Over time, the drugs tend to be less effective and, because the medication is metabolized, the accumulation can damage other organs.
By delivering drugs in nanoemulsions, an IV injection could administer the medication, which is then delivered by the body’s own natural processes to the precise location of the pain. The medication could be administered at a lower-than-typical dose because it is focused at the source of pain and wouldn’t need to travel through other body systems to arrive, thus causing less possible damage to the liver, kidneys and brain over time.
The new findings, published recently in the scientific journal PLOS One, show that inflammatory pain can be seen in living animals through skin and muscle by fluorescence done at Duquesne. The inflammation can also be viewed by MRI, which was achieved through collaboration with T. Kevin Hitchens of Carnegie Mellon University. Future studies will explore the use of drug-loaded nanodroplets, which will carry the drug to where images pinpoint the location where the pain was originating.
“If we can image the inflammation, we can administer drugs to it,” Janjic said, explaining that pain studies typically focus on only biology or behavior, drug delivery or microscopic cell anatomy.
Janjic and Pollock do all this at the same time in the same study. They pointed out that working across disciplines has allowed new insight into issues around pain. “With integrated research, we can figure out how to use data from biology and pharmaceutics; we are feeding real biology into a biologically driven design,” Janjic said. “We’re helping to fulfill a completely unmet need in pain research.”