A derivative of docosahexaenoic acid (DHA), a main ingredient of fish-oil supplements, can alleviate and prevent neuropathic pain caused by sensory system injuries, researchers from Duke University Medical Center reported in the Annals of Neurology.
The authors say that the DHA derivative – a compound called neuroprotectin D1=protectin D1 (NPD1=PD1) – may provide doctors and patients who are concerned about pain medication addictions and opioids with a more natural and healthier alternative.
NPD1=PD1 is a bioactive lipid which cells produce in response to external stimuli. It is present in human white blood cells and plays a role in resolving brain and abdominal inflammation.
Head researcher, Ru-Rong Ji, professor of anesthesiology and neurobiology at Duke University Medical Center, said:
“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.”
In an animal experiment, the scientists used lab mice models of nerve injuries to simulate the pain symptoms commonly linked to nerve trauma caused by surgery. The mice were treated with chemically-synthesized NPD1=PD1, which was administered either locally or by injection, to determine whether the compound might relieve these symptoms.
Not only did NPD1=PD1 relieve pain symptoms, but it also reduced nerve inflammation following the injuries. The compound reduces pain by inhibiting the productions of chemokines and cytokines, small signaling molecules that attract inflammatory macrophages to the nerve cells.
NPD1=PD1 protected nerve cells from further damage by preventing the production of chemokines and cytokines. The lipid compound also reduced neuron firing, resulting in less pain for the injured mice.
Ji said “Chronic pain resulting from major medical procedures such as amputation, chest and breast surgery is a serious problem.”
Current neuropathic pain medications, including gabapentin and several opioids, can lead to dependency and sensory nerve cell destruction.
Below is a list of the main advantages of NPD1=PD1:
- Only low doses are needed to relieve neuropathic pain
- It does not appear to lead to physical dependence
- No enhanced tolerance towards the compound was observed in the mice
- It reduces nerve inflammation following injuries
Ji said “We hope to test this compound in clinical trials.” He suggested that in a preliminary trial, DHA could be administered via diet and injection. “DHA is very inexpensive, and can be converted to NPD1 by an aspirin-triggered pathway.”
The team said their ultimate objective is to develop a safer approach to controlling chronic pain.