A two part-study evaluated the relationship between vitamin D-3 and diabetes related retinopathy. Results of part one indicated that vitamin D-3 can decrease retinal vascular permeability and destruction of retinal cells in rats with diabetes.(Lu et al., 2018) Results of part two that vitamin D-3 has a protective effect from hyperglycemia on human microvascular endothelial cells [like found in the human retina]. Vitamin D-3 reduced inflammation caused by reactive oxygen species stimulated by the TXNIP/NLRP3 pathway (Lu et al., 2018). Further study is needed to determine if the clinical effect vitamin D-3 is a viable treatment regimen for the risk of diabetes related retinopathy.
A review and meta-analysis of pooled results from observational studies was conducted to evaluate any association between diabetes related retinopathy (DRR) and serum levels of vitamin D (25-hydroxyvitamin D). The study lead by Dr. Luo and published in Nutrients demonstrated an association between lower serum levels of vitamin D and diabetes related retinopathy(Luo, Gao, & Qin, 2017). The calculated risk of developing DRR from a vitamin D deficiency was measured at 2.04x. Although the study showed a strong association between vitamin D deficient individuals and DRR, the author suggests further randomized control studies to discover the specific mechanism of action of vitamin D and DRR.
Lu, L., Lu, Q., Chen, W., Li, J., Li, C., & Zheng, Z. (2018). Vitamin D3 Protects against Diabetic Retinopathy by Inhibiting High-Glucose-Induced Activation of the ROS/TXNIP/NLRP3 Inflammasome Pathway. Journal of Diabetes Research, 2018, 8193523. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5842685/ doi:10.1155/2018/8193523
Luo, B.-A., Gao, F., & Qin, L.-L. (2017). The Association between Vitamin D Deficiency and Diabetic Retinopathy in Type 2 Diabetes: A Meta-Analysis of Observational Studies. Nutrients, 9(3), 307.
Vitamin D. Image, (2019). Retrieved and adapted from: https://cdn.shopify.com/s/files/1/1523/4600/files/vitamin-D-receptor_large.jpg?v=1492028904