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Gladys Ko

Associate Professor

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Phone: (979) 845-1797

Mailstop: 4458

Department: VIBS

Photo of Ko, Gladys

Research Keywords

Diabetic retinopathy, novel bioactive peptides, circadian regulation of retinal physiology, signal tranduction in ion channel regulation


  • Ph.D. Neuroscience in Biomedical Sciences, Kent State U. affiliated w/ N.E. Ohio U Col. Med. 1996
  • M.S. Anatomical Sciences, National Yang-Ming Medical College, Taiwan 1991
  • B.S. Biology, National Chang-Kung University, Taiwan 1989


  • Cell Biology
  • Toxicology
  • Neuroscience

Interdisciplinary Activities

  • Neuroscience
  • Toxicology

Scholarly Interests

Diabetic retinopathy (DR) is the leading cause of blindness among the American working population with a projected prevalence of more than 11 million patients by 2030 in the US. Once the disease starts, it cannot be stopped simply by controlling the blood glucose (glycemic) levels strictly through diets and exercise. While DR is a disorder with two major problems, the vascular complications and the neural retina degeneration, the current treatments mainly target the vascular complications without treating the neural retina. The first-line gold standard treatments for DR is regular injections with anti-VEGF agents into the eyes. However, roughly 30% of DR patients do not respond well to these treatments. Often these non-responders are identified months after the treatments have started. Therefore, discovering new ways to treat or prevent DR are a major health issue, which is also the research focus in our laboratory. Interestingly, diabetic patients with retinitis pigmentosa, a congenital blindness with degenerated retinal photoreceptors, rarely develop DR. This suggests that the neural retina, especially the photoreceptors contribute to the development of DR. Our laboratory has been investigated the molecular mechanisms that regulate photoreceptor physiology over 13 years. More specifically, we have been investigating how metabolism and energy expenditure of photoreceptors are regulated throughout the course of 24 hours. We employ different techniques, including electroretinogram (ERG) recordings, fundus angiography, electrophysiological patch-clamp recordings, various biochemical and molecular assays, and imaging at cellular and tissue levels, and now focus on how early diabetic conditions trigger changes in photoreceptors that might lead to DR. In addition, we have recently discovered a new bioactive peptide, peptide Lv. This peptide not only regulates photoreceptor physiology, it also modulates cardiovascular functions. We now further elucidate the molecular mechanisms of peptide Lv's bioactivities, as well as its other unknown function.


The Effects of Metformin on Obesity-Induced Dysfunctional Retinas.
Andy Jeesu Kim, Janet Ya-An Chang, Liheng Shi, Richard Cheng-An Chang, Michael Lee Ko, Gladys Yi-Ping Ko
Investigative ophthalmology & visual science. 2017 58(1):106-118.
Deletion of miR-150 Exacerbates Retinal Vascular Overgrowth in High-Fat-Diet Induced Diabetic Mice.
Liheng Shi, Andy Jeesu Kim, Richard Cheng-An Chang, Janet Ya-An Chang, Wei Ying, Michael L Ko, Beiyan Zhou, Gladys Yi-Ping Ko
PloS one. 2016 11(6):e0157543.
A new role for AMP-activated protein kinase in the circadian regulation of L-type voltage-gated calcium channels in late-stage embryonic retinal photoreceptors.
Cathy C Y Huang, Liheng Shi, Chia-Hung Lin, Andy Jeesu Kim, Michael L Ko, Gladys Y-P Ko
Journal of neurochemistry. 2015 135(4):727-41.
High-Fat Diet-Induced Retinal Dysfunction.
Chang RC, Shi L, Huang CC, Kim AJ, Ko ML, Zhou B, Ko GY
Invest Ophthalmol Vis Sci. 2015 56(4):2367-80.
Chicken embryos as a potential new model for early onset type I Diabetes.
Shi, L.*, Ko, M. L.*, Huang, C. C.-H., Park, S.-Y., Hong, M., Wu, C., Ko, G. Y.-P.
J. Diabetes Research. 2014 2014(2014):354094.
Circadian phase-dependent effect of nitric oxide on L-type voltage-gated calcium channels in avian cone photoreceptors
Ko ML, Shi L, Huang CC, Grushin K, Park SY, Ko GY.
J Neurochem. 2013
A new functional role for mechanistic/mammalian target of rapamycin complex 1 (TORC1) in the circadian regulation of L-type voltage-gated calcium channels in avian cone photoreceptors
Huang, C. C.-H., Ko, M. L., Ko, G. Y.-P.
PLoS ONE. 2013 8(8).
Identification of Peptide lv, a novel putative neuropeptide that regulates the expression of L-type voltage-gated calcium channels in photoreceptors.
Shi L, Ko ML, Abbott LC, Ko GY
PLoS One. 2012 7(8).
Calcineurin serves in the circadian output pathway to regulate the daily rhythm of L-type voltage-gated calcium channels in the retina.
Huang CC, Ko ML, Vernikovskaya DI, Ko GY
J Cell Biochem. 2012 113(3):911-22.
Cardiac-specific mutation of Clock alters the quantitative measurements of physical activities without changing behavioral circadian rhythms.
Ko ML, Shi L, Tsai JY, Young ME, Neuendorff N, Earnest DJ, Ko GY
J Biol Rhythms. 2011 26(5):412-22.
Rhythmic expression of microRNA-26a regulates the L-type voltage-gated calcium channel alpha1C subunit in chicken cone photoreceptors.
Shi L, Ko ML, Ko GY
J Biol Chem. 2009 284(38):25791-803.
Inhibitory effect of somatostatin-14 on L-type voltage-gated calcium channels in cultured cone photoreceptors requires intracellular calcium.
Jian K, Barhoumi R, Ko ML, Ko GY
J Neurophysiol. 2009 102(3):1801-10.
Circadian regulation of ion channels and their functions.
Ko GY, Shi L, Ko ML
J Neurochem. 2009 110(4):1150-69.
Phosphatidylinositol 3 kinase-Akt signaling serves as a circadian output in the retina.
Ko ML, Jian K, Shi L, Ko GY
J Neurochem. 2009 108(6):1607-20.
Retinoschisin, a new binding partner for L-type voltage-gated calcium channels in the retina.
Shi L, Jian K, Ko ML, Trump D, Ko GY
J Biol Chem. 2009 284(6):3966-75.
Circadian controls outweigh acute illumination effects on the activity of extracellular signal-regulated kinase (ERK) in the retina.
Ko ML, Shi L, Ko GY
Neurosci Lett. 2009 451(1):74-8.
Circadian regulation of retinoschisin in the chick retina.
Ko ML, Liu Y, Shi L, Trump D, Ko GY
Invest Ophthalmol Vis Sci. 2008 49(4):1615-21.
The expression of L-type voltage-gated calcium channels in retinal photoreceptors is under circadian control.
Ko ML, Liu Y, Dryer SE, Ko GY
J Neurochem. 2007 103(2):784-92.

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