The purpose of this study was to determine the effect of supplementing the diet of a mouse model of type 2 diabetes with menhaden (fish) oil or daily treatment with resolvin D1 on diabetic neuropathy. The endpoints evaluated included motor and sensory nerve conduction velocity, thermal sensitivity, innervation of sensory nerves in the cornea and skin and the retinal ganglion cell complex thickness. Menhaden oil is a natural source for n-3 polyunsaturated fatty acids, which have been shown to have beneficial effects in other diseases. Resolvin D1 is a metabolite of docosahexaenoic acid, and is known to have anti-inflammatory and neuroprotective properties. To model type 2 diabetes mice were fed a high fat diet for 8 weeks followed by a low dosage of streptozotocin. After 8 weeks of hyperglycemia, mice in experimental groups were treated for 6 weeks with menhaden oil in the diet or daily injections of 1 ng/g body weight resolvin D1. Our findings show that menhaden oil or resolvin D1 did not improve elevated blood glucose, HbA1C or glucose utilization. Untreated diabetic mice were thermal hypoalgesic, had reduced motor and sensory nerve conduction velocities, decrease innervation of the cornea and skin and had thinner retinal ganglion cell complex. These endpoints were significantly improved with menhaden oil or resolvin D1 treatment. Exogenously, resolvin D1 stimulated neurite outgrowth from primary cultures of dorsal root ganglion neurons from normal mice. These studies suggest that n-3 polyunsaturated fatty acids derived from fish oil could be an effective treatment for diabetic neuropathy.
- diabetic neuropathy
- fish oil
- corneal nerve fibers
- epidermal nerve fibers
- Copyright © 2015, Journal of Neurophysiology