Diabetic retinopathy (DR) is the most common diabetic vascular complication. Despite recent advances in therapeutics and management diabetes, DR remains the leading cause of severe vision loss in people under age of sixty. Growing evidence indicates that hyperactivity of the vasoconstrictive, proliferative, pro-inflammatory, and fibrotic axis (angiotensin-converting enzyme [ACE]/angiotensin II [Ang II]/angiotensin type I receptor [AT1R]) of the renin- angiotensin-system (RAS) plays a central role in the pathogenesis of DR. Nevertheless, inhibitors to this axis of RAS have not proven to be effective in the treatment and prevention of DR in several clinical trials, thus a conceptual breakthrough is imperative to identify novel targets and therapeutic strategies. We believe that our provocative preliminary data coupled with recent evidence of the protective role of the recently discovered vasoprotective axis of the RAS offer such a breakthrough. The protective axis of the RAS involves the angiotensin converting enzyme 2 (ACE2) by generating angiotensin-(1-7) which acts through the receptor Mas, attenuates the vasoconstrictive, proliferative, fibrotic and hypertrophic effects of angiotensin II, the key member of the deleterious axis of RAS. Our Central Hypothesis is that a delicate balance between the vasoprotective and vasodeleterious axis of retinal RAS is critical to the maintenance of normal retinal vascular physiology. Any impairment of this balance, induced by diabetes or other risk factors, leads to the development of DR. Thus an increase in the activity of the vasoprotective axis will overcome the imbalance of the retinal RAS, protect the development and progression of DR, and prevent the adverse metabolic memory. Our goal of this proposal is to (1) investigate the role of the vasoprotective axis of the RAS in reversing diabetes-induced retinal vascular dysfunctions using local gene transfer approach to restore the balance of ocular RAS;study whether genetic depletion of Mas in the retina will accelerate diabetic retinopathy and blunt the protective effects of ACE2 or Ang-(1-7); and (2) examine the role of local retinal hyperactivity of ACE/Ang II/AT1R axis induced by diabetes in metabolic memory. The proposed studies will (1) provide evidence for our novel hypothesis;(2) establish the mechanism that leads to a chronic dysregulation of the retinal RAS in diabetes;and (3) put us in a strong position to transition into the clinical arena to test whether ACE2/Ang-(1-7) gene transfer would be therapeutic for DR.
Research Narrative: The overall goal of this application is to study the role of ACE2/Ang-(1-7) in reversing diabetes- induced retinal vascular dysfunctions using ocular gene transfer, identify the protective mechanism of ACE2/Ang1-7, and examine the role of ocular RAS in metabolic memory. The outcome of this proposed research will immediately impact the clinical care of patients with diabetic retinopathy, and identify novel mechanisms and targets for therapeutic intervention.
|Beli, Eleni; Yan, Yuanqing; Moldovan, Leni et al. (2018) Restructuring of the Gut Microbiome by Intermittent Fasting Prevents Retinopathy and Prolongs Survival in db/db Mice. Diabetes 67:1867-1879|
|Li, Yiming; Zhu, Ping; Verma, Amrisha et al. (2017) A novel bispecific molecule delivered by recombinant AAV2 suppresses ocular inflammation and choroidal neovascularization. J Cell Mol Med 21:1555-1571|
|Prasad, Tuhina; Zhu, Ping; Verma, Amrisha et al. (2017) Amyloid ? peptides overexpression in retinal pigment epithelial cells via AAV-mediated gene transfer mimics AMD-like pathology in mice. Sci Rep 7:3222|
|Qiu, Yiguo; Tao, Lifei; Zheng, Shijie et al. (2016) AAV8-Mediated Angiotensin-Converting Enzyme 2 Gene Delivery Prevents Experimental Autoimmune Uveitis by Regulating MAPK, NF-?B and STAT3 Pathways. Sci Rep 6:31912|
|Dominguez 2nd, James M; Hu, Ping; Caballero, Sergio et al. (2016) Adeno-Associated Virus Overexpression of Angiotensin-Converting Enzyme-2 Reverses Diabetic Retinopathy in Type 1 Diabetes in Mice. Am J Pathol 186:1688-700|
|Prasad, Tuhina; Roksnoer, Lodi C W; Zhu, Ping et al. (2016) Beneficial Effects of Combined AT1 Receptor/Neprilysin Inhibition (ARNI) Versus AT1 Receptor Blockade Alone in the Diabetic Eye. Invest Ophthalmol Vis Sci 57:6722-6730|
|Ildefonso, Cristhian J; Jaime, Henrique; Brown, Emily E et al. (2016) Targeting the Nrf2 Signaling Pathway in the Retina With a Gene-Delivered Secretable and Cell-Penetrating Peptide. Invest Ophthalmol Vis Sci 57:372-86|
|Kohli, Neha; Westerveld, Donevan R; Ayache, Alexandra C et al. (2014) Oral delivery of bioencapsulated proteins across blood-brain and blood-retinal barriers. Mol Ther 22:535-546|
|Ha, Jung-Heun; Shil, Pollob Kumar; Zhu, Ping et al. (2014) Ocular inflammation and endoplasmic reticulum stress are attenuated by supplementation with grape polyphenols in human retinal pigmented epithelium cells and in C57BL/6 mice. J Nutr 144:799-806|
|Jiang, Ke; Wright, Katherine L; Zhu, Ping et al. (2014) STAT3 promotes survival of mutant photoreceptors in inherited photoreceptor degeneration models. Proc Natl Acad Sci U S A 111:E5716-23|
Showing the most recent 10 out of 20 publications