A derivative of fish oil has shown potential for developing a new pain treatment that could become an alternative to addictive opioid pain killers, according to new research from Duke University.

Researchers found that a derivative of docosahexaenoic acid, or DHA, can soothe and prevent neuropathic pain caused by injuries to the sensory system. DHA is a main ingredient of over-the-counter fish oil supplements.

The research focused on a compound called neuroprotectin D1=protectin D1 (NPD1=PD1). It’s a bioactive lipid produced by cells in response to external stimuli. This compound is present in human white blood cells and was initially identified because for its ability to resolve abdominal and brain inflammation.

“These compounds are derived from omega-3 fatty acids found in fish oil, but are 1,000 times more potent than their precursors in reducing inflammation,” Ru-Rong Ji, professor of anesthesiology and neurobiology at Duke University Medical Center and principal investigator of the study said in a statement.

The research team used mouse models of nerve injuries to simulate pain systems that are commonly associated with post-surgical nerve trauma. The animals were treated with chemically synthesized NPDI=PD1 to see whether the compound relieved the pain.

The study showed that the compound alleviated the pain and also reduced nerve swelling. Duke says that the analgesic effect comes from the compound’s ability to inhibit the production of cytokines and chemokines, signaling molecules that attract inflammatory macrophages to the nerve cells. Preventing cytokine and chemokine production protected nerve cells from further damage. The compound also reduced neuron firing so the injured animals felt less pain.

Ji said he believes the findings show potential for treatment in humans.

“Chronic pain resulting from major medical procedures such as amputation, chest and breast surgery is a serious problem,” he said. Current treatment options for neuropathic pain include gabapentin and various opioids, which may lead to addiction and destruction of the sensory nerves.

The NPD1=PD1 compound demonstrated ability to relieve neuropathic pain at very low doses. Also, mice receiving the treatment did not show signs of physical dependence or enhanced tolerance toward the lipid compound. That suggests the compound could be developed into a pain-killer that poses less addiction risk.
The research was supported by grants from the National Institutes of Health. The study results appear online in the Annals of Neurology.