Much Ado About Eating
Dietary therapy has been used since ancient times to treat the symptoms of disease and disorder. Dietary therapy has long captured the interest of the public in modern times, dating back to the mid-nineteenth century with Englishman William Banting's "Letter on Corpulence, Addressed to the Public", which addressed Banting's anecdotal use of a high-fat diet to treat obesity. High-fat diets became popular in the United States in the early twentieth-century to treat epilepsy. The utility of dietary therapy to treat diseases and disorder has not been embraced widely, as there is a paucity of standardized clinical trials that demonstrate robust safety and therapeutic efficacy for specific diseases and disorders. Additionally, preclinical studies of dietary therapy do not adhere to standardized guidelines, which can hinder cross-study interpretation and reproducibility. To that end, my dissertation updates diet implementation guidelines for preclinical studies that adhere to standardized experimental design and biomarker monitoring in mouse models in order to maximize therapeutic efficacy, diet regimen safety, and cross-study interpretability. With these guidelines, I explored the effect of various diets on circulating glucose and ketone bodies in mice, a measure of glycolytic flux, along with biomarkers of health. I found that calorie-restricted diets, regardless of macronutrient composition, lowers circulating glucose and increases circulating ketone levels, along with improving biomarkers of health, including lowering circulating triglyceride levels. In demonstrating the utility of dietary therapy to treat disease, I also explored the mechanisms on how dietary therapy can be used to treat epilepsy in a preclinical mouse model. I showed that reduced glucose utilization underlies the seizure-protective effects of dietary therapy in EL mice, a mouse model of idiopathic epilepsy. Lastly, I developed a novel tool, the Glucose Ketone Index Calculator, to track the progress of dietary therapy in brain cancer patients through a ratio of circulating glucose to circulating ketone bodies. Evidence is presented that demonstrates a low ratio of glucose to ketone bodies is associated with improved prognosis of brain cancer management in humans and mice. Overall, this dissertation demonstrates the utility of dietary therapy in treating disease using standardized guidelines, and suggests the use of a novel tool to apply and track the progress of dietary therapy in the clinical brain cancer population.