T. Zarnowski, M. Tulidowicz-Bielak, I. Zarnowska, K. Mitosek-Szewczyk, A. Wnorowski, K. Jozwiak, M. Gasior, et al. (2017). Kynurenic Acid and Neuroprotective Activity of the Ketogenic Diet in the Eye. Current medicinal chemistry, 24(32), 3547-3558. https://doi.org/10.2174/0929867324666170509120257

PubMed 28486923

[Abstract]
BACKGROUND: There is growing evidence of the involvement of the kynurenine metabolic pathway and the enhancement of kynurenic acid production in the neuroprotective effects of the ketogenic diet.

OBJECTIVE: Here, we review evidence implicating kynurenic acid in the efficacy of ketogenic diet in eye diseases associated with neurodegeneration.

FINDINGS: Ketogenic diet and ketone bodies that are elevated during exposure to the ketogenic diet each have a neuroprotective effect on retinal ganglion cells in a rat model of Nmethyl- D-aspartate induced neuronal damage. Chronic exposure to ketogenic diet also increases kynurenic acid concentrations in discrete rat brain structures. A non-selective glutamate receptor agonist, glutamate, also decreases the production of kynurenic acid in bovine retinal slices; this effect is attenuated by acetoacetate and β-hydroxybutyrate, two of three ketone bodies overproduced during ketogenic diet.

PERSPECTIVE: Whether ketogenic diet induced enhancement of kynurenic acid production would translate into a clinically significant improvement in certain eye diseases like glaucoma and retinal neurodegenerations awaits further experimental and clinical verification.