Effect of Ketogenic Diet on Survival of Magnocellular Neurons Following Infundibular Nerve Crush Injury

Abstract

Our experimental objectives were to first determine the effect of two ketogenic diet (KD) formulations on neuroendocrine function and determine the extent to which these ketogenic diets increase plasma ketone levels in rats. Second, we sought to determine the effect of KD and its specific metabolites on alleviation of traumatic brain injury (TBI) ‐induced diabetes insipidus (DI) and the survival of compromised supraoptic magnocellular neurons that are selectively vulnerable to TBI insult.Methods utilized included immunocytochemical and metabolic analysis, stereometric assessment of neuronal survival, analysis of plasma ß‐hydroxybutyrate and acetoacetate levels, and infundibular nerve crush.Our results demonstrate that after a 4 week administration of 18% protein KD, plasma ketone levels of β‐hydroxybutyrate and acetoacetate were significantly increased over control diet values in the absence of caloric restriction. Plasma ketone body levels were also significantly increased with 8% protein KD although there was marked caloric restriction associated with this formulation. Interestingly, the 18% protein KD had substantially higher ketone body levels than the 8% protein KD. However, despite increased ketone body levels, no improvement in survival of magnocellular supraoptic neurons was observed following infundibular nerve crush. Nor was there any dietary effect on alleviation of injury induced DI.