Laboratory Research
Oakland University William Beaumont School of Medicine
586 Pioneer Drive
Rochester, MI 48309
(248) 370-3634
Oakland University William Beaumont School of Medicine
This section includes Class of 2025 Embark Projects within the Laboratory & Bench research disciplines. These projects include traditional bench research in a variety of basic and clinical science areas.
Impact of Maternal Diabetes on Retinal Thickness and Vascular Density in Offspring: A Developmental Study
Jonathan Blake, B.S.1, Mohamed Moustafa, Pharm.D.2, Min Young Kim, M.D./Ph.D.1, Mohamed Al-Shabrawey, M.D./Ph.D.2, 3
1Oakland University William Beaumont School of Medicine, Rochester, MI
2Eye Research Center Oakland University School of Medicine, Rochester, MI
3Department of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Rochester, MI
INTRODUCTION
Offspring born to diabetic mothers are at risk of developing structural changes in the retina, potentially compromising vision. This study investigates the impact of maternal diabetes on retinal thickness and morphology in the offspring.
METHODS
Diabetes was induced in female mice via intraperitoneal streptozotocin injections. After four weeks, diabetic females mated with wild-type males. Offspring were sacrificed at postnatal days 3, 7, 14, 21, and 30. Eyes were collected, sectioned into 12 μm slices, stained with IsolectinB4 and DAPI . Fluorescent microscopy captured images, and ImageJ measured inner layer and entire retinal thickness. Comparisons were made between offspring two groups (≥3 mice/postnatal-day). ImageJ was used to measure vessels relative to surface area.
RESULTS
At p7, total retinal thickness in control offspring was 194 μm ± 46.46, versus 181.3 μm ± 7.054 in offspring of diabetic. At p14, control thickness was 202.9 μm ± 32.37, vs 179.0 μm ± 25.45 in diabetic offspring. At p21, control thickness was 210.4 μm ± 35.12, vs 166.2 μm ± 24.37 in diabetic offspring. At p30, control thickness was 168.1 μm ± 46.36, vs 159.6 μm ± 46.52 in diabetic offspring. Reductions in retinal thickness were observed in diabetic offspring at p14 and p21 (p < 0.05), with a 15% overall reduction in total retinal thickness compared to control among all age groups. No significant differences in thickness of the inner retina except at p21 where the mean of inner retina thickness was 78.63 μm ± 18 in control vs 55.4 μm ± 7.3 in diabetic. Vascular density showed a significant reduction of retinal vessels in diabetic offspring at p14 compared to the age-matched control offspring.
CONCLUSIONS
Maternal diabetes affects retinal thickness and vasculature in offspring, especially between p14-p21, risking vision impairment. Conscientious management of maternal diabetes during pregnancy is vital to prevent harmful effects on offspring retinas.
Hyperglycemia, Hypoxia, and their Synergistic Effects on miRNA Expression in Human Retinal endothelial Cells
Suhani Gupta, B.A.1, Chloe Connelly, B.S.1, Khaled Elmasry, M.D./Ph.D.2, Mohamed A. Al-Shabrawey, M.D./Ph.D.3
1Oakland University William Beaumont School of Medicine, Rochester, MI
2Dental College of Georgia, Augusta, GA
3Eye Research Center, Oakland University William Beaumont School of Medicine, Rochester, MI
INTRODUCTION
Epigenetic modifications, especially microRNA (miR) alterations, play a crucial role in driving retinal endothelial cell dysfunction and subsequent angiogenesis in diabetic retinopathy. This study aims to explore the impact of hyperglycemia and hypoxia on miRNA expression in human retinal endothelial cells (HRECs) to identify potential targets for diabetic retinopathy (DR) treatment.
METHODS
HRECs were treated with high glucose (HG, 25 mM D-glucose), hypoxia (1% oxygen), or a combination of HG and hypoxia for 5 days. Osmotic control (5 mM D-glucose + 20 mM L-glucose) and normoxia (21% O2) served as control conditions. RNA was hybridized to the GeneChip miRNA 3.0 array (Affymetrix), and data were analyzed using Partek Genomic Suites version 6.6, for miR differential expression.
RESULTS
Differential effects were observed for HG and hypoxia on miR expression. HG significantly dysregulated (up and down) 8% of miRs, while hypoxia affected 5% (p < 0.045). The combined effect of HG and hypoxia induced significant changes in 63 miRs compared to HG alone, while hypoxia differentially dysregulated 38 miRs compared to combined treatment by HG and hypoxia. There were 9 miRs implicated in angiogenesis (e.g., miR-124, miR20b, miR718) which were mutually and similarly affected by both conditions. MiR-124-3p, critical in regulating hypoxia's effects, showed a -22-fold change in HG-treated HRECs compared to controls but increased by 4-fold in the HG + hypoxia group. MiR-328-3p, not significantly impacted by HG alone, exhibited a -3-fold change in the combined treatment group, suggesting enhanced angiogenesis under hypoxic conditions.
CONCLUSIONS
Pathological neovascularization under hyperglycemic conditions is profoundly influenced by hypoxia. Exposure to high glucose and hypoxia resulted in substantial dysregulation of multiple miRs in HRECs, all pivotal in the regulation of angiogenesis. Notably, the upregulation of miR-124-3p and downregulation of miR-328-3p were observed underscoring the potential of these miRs as promising prognostic and therapeutic targets in DR.
