Tracing Retinal Metabolism Through Intravitreal Injection of Labeled Glucose

Emily V. Adis*, Rong Xu, and Jianhai Du
Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV 26505

Presentation No.: 6

Assigned Category (Presentation Format): Biological & Health Sciences (Oral Presentations)

Student’s Major: Biochemistry

Glucose is the major energy source for the eye’s retina. Improper glucose metabolism has been linked to degenerative retinal diseases, including diabetic retinopathy and age-related macular degeneration. Studying glucose metabolism is vital to understand the metabolic basis of retinal diseases. 13C glucose has been widely used to trace glucose metabolism, however, current options of intravenous, intraperitoneal, and oral delivery have systemic side effects. Our aim is to develop an eye-specific method to trace glucose metabolism. We intravitreally injected 13C glucose into one eye of 2-month old mice and harvested ocular tissues and blood at different times to measure metabolites derived from 13C glucose using mass spectrometry. 13C glucose-labeled retinal intermediates in glycolysis and the tricarboxylic acid cycle peaked at 5 and 15 minutes, but tapered off within 1 hour and disappeared 8 hours after injection. 13C labeled metabolites were absent in the blood and control eye. We confirmed eye-specific glucose uptake by imaging with fluorescent-labeled glucose using a confocal microscope. In conclusion, we developed a simple, cost-effective, eye-specific method for tracing glucose metabolism in vivo.

Funding: NIH

Program/mechanism supporting research/creative efforts: the WVU Vision Research Fellowship Program (Jianha Du)