Increased Retinal Oxygen Metabolism Precedes Microvascular Alterations in Type 1 Diabetic Mice.
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ABSTRACT: Purpose
To investigate inner retinal oxygen metabolic rate (IRMRO2) during early stages of type 1 diabetes in a transgenic mouse model.Methods
In current study, we involved seven diabetic mice (Akita/+, TSP1-/-) and seven control mice (TSP1-/-), and applied visible-light optical coherence tomography (vis-OCT) to image functional parameters including retinal blood flow rate, oxygen saturation (sO2) and the IRMRO2 value longitudinally from 5 weeks of age to 13 weeks of age. After imaging at 13 weeks of age, we analyzed the imaging results, and examined histology of mouse retina.Results
Between diabetic mice and the control group, we observed significant differences in venous sO2 from 9 weeks of age (P = 0.006), and significant increment in IRMRO2 from 11 weeks of age (P = 0.001) in diabetic mice compared with control group. We did not find significant differences in retinal blood flow rate as well as arterial sO2 during imaging between diabetic and control mice. Histologic examination of diabetic and control mice at 13 weeks of age also revealed no anatomical retinal alternations.Conclusions
In diabetic retinopathy, complications in retinal oxygen metabolism may occur before changes of retinal anatomical structure.
SUBMITTER: Liu W
PROVIDER: S-EPMC5308771 | biostudies-literature | 2017 Feb
REPOSITORIES: biostudies-literature
Publications
Increased Retinal Oxygen Metabolism Precedes Microvascular Alterations in Type 1 Diabetic Mice.
Liu Wenzhong W Wang Shoujian S Soetikno Brian B Yi Ji J Zhang Kevin K Chen Siyu S Linsenmeier Robert A RA Sorenson Christine M CM Sheibani Nader N Zhang Hao F HF
Investigative ophthalmology & visual science 20170201 2
<h4>Purpose</h4>To investigate inner retinal oxygen metabolic rate (IRMRO2) during early stages of type 1 diabetes in a transgenic mouse model.<h4>Methods</h4>In current study, we involved seven diabetic mice (Akita/+, TSP1-/-) and seven control mice (TSP1-/-), and applied visible-light optical coherence tomography (vis-OCT) to image functional parameters including retinal blood flow rate, oxygen saturation (sO2) and the IRMRO2 value longitudinally from 5 weeks of age to 13 weeks of age. After i ...[more]
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