When
Monday, September 8, 2025 at 12:00 p.m.
Erika D. Eggers
Associate Department Head of Research and Professor of Physiology
Professor of Biomedical Engineering
Professor of Physiological Sciences and Neuroscience, Graduate Interdisciplinary Program
Professor of the BIO5 Institute
"Early Retinal Circuit Dysfunction in Diabetes"
Keating 103 | Zoom link
Instructor permission is required for enrolled students attending via Zoom.
Host: Swarna Ganesh
Abstract: The retina is a complex circuit of neurons that converts light sensed by photoreceptors into action potentials sent to the rest of the brain through the optic nerve. Diabetes causes significant visual and retinal complications, collectively called diabetic retinopathy. Clinically, diabetic retinopathy is diagnosed as a vascular disease, but significant dysfunction occurs in the retinal neuronal circuit prior to development of overt diabetic retinopathy. We study the electrical activity in this circuit at the single-cell and whole retinal levels and have found significant neuronal dysfunction in early diabetes. We have used single-cell electrophysiology, light stimulation, optogenetic stimulation and immunohistochemistry/confocal imaging to show that inhibitory inputs in the retina that shape the retinal output are reduced due to calcium dysfunction, leading to increased excitation. Using similar techniques, we have also shown that reduced dopamine levels in the diabetic retina cause changes in the retinal responses to dopamine and increased light levels that also lead to increased excitation after light adaptation. Both of these pathways of damage suggest targets for early treatment of diabetic neuronal damage.
Bio: Erika D. Eggers' Laboratory of Retinal Neurophysiology investigates how inhibitory synapses and neuromodulators shape visual processing and how early diabetes disrupts retinal function, using electrophysiology and imaging approaches.