Diabetic Neuropathy May Respond to Fish Oil
Results of a new study suggest that fish oil may help restore the nerve damage associated with diabetic neuropathy. The study was conducted in mice, and there are plans to perform studies in diabetic patients with neuropathy.
Diabetic neuropathy affects about half of individuals who have diabetes. Currently there is no cure for this diabetic complication, which can have a devastating impact on mobility and quality of life.
When people hear about fish oil, they typically think of the two main omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). However, there’s a bit more to the story, as this study has shown.
A research team at the VA Medical Center in Iowa City knew that previous studies had shown that omega-3 fatty acids helped diabetic neuropathy in diseased rats as well as improved blood glucose management and reduced inflammation in diabetes. In the latter case, special molecules produced from omega-3 fatty acids, called resolvins, were believed to be the beneficial factors.
Resolvins are compounds that the body produces from EPA and DHA. Research shows that resolvins have anti-inflammatory properties.
In this latest study, the authors compared three groups of mice: one group was fed a high-fat diet and treated daily with resolvin; one group was given a high-fat diet in which 50 percent of the fat was from fish oil (from menhaden fish); and a control group consisted of healthy, nondiabetic mice. Menhaden fish are an excellent source of not only EPA and DHA, but another fatty acid, docosapentaenoic acid (DPA).
Here’s what the researchers discovered:
- he untreated mice had signs of neuropathy—diminished transmission of signals along the nerves in the paws along with fewer nerves in the skin, reduced sense of touch, and fewer nerves in the eyes
- Mice in the resolvin and fish oil groups showed improved nerve health
- Resolvin stimulated nerve cell growth
- Fish oil and resolvin did not result in improvements in blood glucose levels
According to one of the study’s authors, Mark A. Yorek, of the University of Iowa, the animal research findings “suggest that fish oil can reverse some of the harmful effects of diabetes on the nerves.” Further studies are needed to determine whether fish oil can reverse nerve damage associated with prolonged poorly controlled diabetes in animals, and then human trials can begin.
Other treatments for diabetic neuropathy
The best way to prevent and treat diabetic neuropathy is to maintain good blood glucose levels through diet, exercise, stress management, and weight control. Numerous natural remedies, such as B vitamins, alpha lipoic acid, and others, also can be helpful.
The Food and Drug Administration has approved three drugs to treat painful diabetic neuropathy. These drugs, which include duloxetine (an antidepressant), pregabalin (an anticonvulsant), and tapentadol (an opioid/antidepressant combination), are all associated with significant side effects.
A new approach includes the use of gene therapy using a growth factor protein that promotes and supports function of the cells. Following the promising results seen in a Phase II trial, researchers are planning a Phase III study.
Shevalye H et al. Effect of enriching the diet with menhaden oil or daily treatment with resolving D1 on neuropathy in a mouse model of type 2 diabetes. Journal of Neurophysiology 2015; jn.0224.2015
Yazdi PG. A review of the biologic and pharmacological role of docosapentaenoic acid. F1000 Research 2013; 2:256