Browsing by Subject "Diabetic macular edema"

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    Chemically induced partial unfolding of the multifunctional Apurinic/apyrimidinic endonuclease 1
    (bioRxiv, 2023-06-29) Rai, Ratan; Dawodu, Olabode I.; Johnson, Steven M.; Vilseck, Jonah Z.; Kelley, Mark R.; Ziarek, Joshua J.; Georgiadis, Millie M.; Biochemistry and Molecular Biology, School of Medicine
    Targeting of the multifunctional enzyme apurinic/apyrimidinic endonuclease I/redox factor 1 (APE1) has produced small molecule inhibitors of both its endonuclease and redox activities. While one of the small molecules, the redox inhibitor APX3330, completed a Phase I clinical trial for solid tumors and a Phase II clinical trial for Diabetic Retinopathy/Diabetic Macular Edema, the mechanism of action for this drug has yet to be fully understood. Here, we demonstrate through HSQC NMR studies that APX3330 induces chemical shift perturbations (CSPs) of both surface and internal residues in a concentration-dependent manner, with a cluster of surface residues defining a small pocket on the opposite face from the endonuclease active site of APE1. Furthermore, APX3330 induces partial unfolding of APE1 as evidenced by a time-dependent loss of chemical shifts for approximately 35% of the residues within APE1 in the HSQC NMR spectrum. Notably, regions that are partially unfolded include adjacent strands within one of two beta sheets that comprise the core of APE1. One of the strands comprises residues near the N-terminal region and a second strand is contributed by the C-terminal region of APE1, which serves as a mitochondrial targeting sequence. These terminal regions converge within the pocket defined by the CSPs. In the presence of a duplex DNA substrate mimic, removal of excess APX3330 resulted in refolding of APE1. Our results are consistent with a reversible mechanism of partial unfolding of APE1 induced by the small molecule inhibitor, APX3330, defining a novel mechanism of inhibition.
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    Longer-Term Anti-VEGF Therapy Outcomes in Neovascular Age-Related Macular Degeneration, Diabetic Macular Edema, and Vein Occlusion-Related Macular Edema: Clinical Outcomes in 130 247 Eyes
    (Elsevier, 2022-09) Ciulla, Thomas A.; Hussain, Rehan M.; Taraborelli, Donna; Pollack, John S.; Williams, David F.; Ophthalmology, School of Medicine
    Purpose The clinical practice visual acuity (VA) outcomes of anti-VEGF therapy for up to 5 years were assessed in patients with neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME), branch retinal vein occlusion-related macular edema (BRVO-ME), and central retinal vein occlusion-related macular edema (CRVO-ME). Design A retrospective analysis was performed using the Vestrum Health Retina Database. Participants Treatment-naive patients with nAMD, DME, BRVO-ME, or CRVO-ME who received anti-VEGF injections between 2014 and 2019 and had follow-up data for ≥12 months. Methods Data on age, sex, the number of anti-VEGF treatments, and VA were analyzed. Main Outcome Measures Mean VA change up to 3 years (BRVO-ME and CRVO-ME) and 5 years (nAMD and DME). Results At 1, 3, and 5 years, in 67 666, 21 305, and 5208 eyes with nAMD, after a mean of 7.6, 19.5, and 32 injections, there was a mean change of +3.1, −0.2, and −2.2 letters, respectively. At 1, 3, and 5 years, in 40 832, 7728, and 1192 eyes with DME, after a mean of 6.2, 15.4, and 26.0 injections, there was a mean change of +4.7, +3.3, and +3.1 letters, respectively. At 1 and 3 years, in 12 451 and 3027 eyes with BRVO-ME, after a mean of 7.1 and 18.2 injections, there was a mean change of +9.5 and +7.7 letters, respectively. At 1 and 3 years, in 9298 and 2264 eyes with CRVO-ME, after a mean of 7.3 and 18.8 injections, there was a mean change of +8.3 and +6.0 letters, respectively (P < 0.01 for all VA changes of > 1 letter). In all 4 conditions, the mean VA increased with the mean number of anti-VEGF injections, eyes with a baseline VA of 20/40 or better tended to lose VA, and eyes with progressively worse baseline VA experienced a progressively greater VA gain at 3 years. Conclusions In practice, patients with nAMD, DME, BRVO-ME, and CRVO-ME showed limited visual outcomes, with patients with nAMD tending to lose VA at 3 and 5 years. Across all 4 disorders, the mean change in VA correlated with treatment intensity at 1, 3, and 5 years. Patients with better baseline VA are more vulnerable to vision loss.
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    The evolving therapeutic landscape of diabetic retinopathy
    (Taylor & Francis, 2023) Shughoury, Aumer; Bhatwadekar, Ashay; Jusufbegovic, Denis; Hajrasouliha, Amir; Ciulla, Thomas A.; Ophthalmology, School of Medicine
    Introduction: Diabetic retinopathy (DR) is a leading cause of blindness worldwide. Recent decades have seen rapid progress in the management of diabetic eye disease, evolving from pituitary ablation to photocoagulation and intravitreal pharmacotherapy. The advent of effective intravitreal drugs inhibiting vascular endothelial growth factor (VEGF) marked a new era in DR therapy. Sustained innovation has since produced several promising biologics targeting angiogenesis, inflammation, oxidative stress, and neurodegeneration. Areas covered: This review surveys traditional, contemporary, and emerging therapeutics for DR, with an emphasis on anti-VEGF therapies, receptor tyrosine kinase inhibitors, angiopoietin-Tie2 pathway inhibitors, integrin pathway inhibitors, gene therapy 'biofactory' approaches, and novel systemic therapies. Some of these investigational therapies are being delivered intravitreally via sustained release technologies for extended durability. Other investigational agents are being delivered non-invasively via topical and systemic routes. These strategies hold promise for early and long-lasting treatment of DR. Expert opinion: The evolving therapeutic landscape of DR is rapidly expanding our toolkit for the effective and durable treatment of blinding eye disease. However, further research is required to validate the efficacy of novel therapeutics and characterize real world outcomes.