The effects of a ketogenic diet on sensorimotor function in a thoracolumbar mouse spinal cord injury model.

Mayr, Kyle A; Kwok, Charlie H T; Eaton, Shane E A; Baker, Glen B; Whelan, Patrick J

Spinal cord injury (SCI) and peripheral nerve injuries are traumatic events that greatly impact quality of life. One factor that is being explored throughout patient care is the idea of diet and the role it has on patient outcomes. But the effects of diet following neurotrauma need to be carefully explored in animal models to ensure that they have beneficial effects. The ketogenic diet provides sufficient daily caloric requirements while being potentially neuroprotective and analgesic. In this study, animals were fed a high fat, low carbohydrate diet that led to a high concentration of blood ketone levels that was sustained for as long as the animals were on the diet. Mice fed a ketogenic diet had significantly lower levels of tyrosine and tryptophan but the levels of other monoamines within the spinal cord remained similar to control mice. Mice were fed a standard or ketogenic diet for 7 days before, and 28 days following the injury. Our results show that mice hemisected over the T10-11 vertebrae showed no beneficial effects of being on a ketogenic diet over a 28 day recovery period. Similarly, ligation of the common peroneal and tibial nerve showed no differences between mice fed normal or ketogenic diets. Tests included von Frey, open field, and ladder-rung crossing. We add to existing literature showing protective effects of the ketogenic diet in forelimb injuries by focusing on neurotrauma in the hindlimbs. The results suggest that ketogenic diets need to be assessed based on the type and location of neurotrauma.Significance Statement There is an urgent need for therapeutics to improve outcomes for patients with neurotrauma. Here we test the effects of a non-invasive diet-based therapy. Ketogenic diets, which are high fat and low carbohydrate-based, have been shown to be effective in treating epilepsy, Parkinson's Disease, and show promise for treating other neurotrauma and neurodegenerative conditions. Here we show that while we were successful in producing high ketone concentrations in mice, the effects on recovery of function and pain following a thoracic spinal cord hemisection or spared nerve injury were minimal. Therefore, ketogenic diets, while effective in certain cases, should be evaluated depending on the injury type.