1
|
Du L, Sun J, Liu J, Xu N, Liu M, Wu X. Effect of Conbercept on Corneal Neovascularization in a Rabbit Model. Semin Ophthalmol 2023; 38:670-678. [PMID: 37058000 DOI: 10.1080/08820538.2023.2201652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 11/30/2022] [Accepted: 01/23/2023] [Indexed: 04/15/2023]
Abstract
OBJECTIVE To study the efficacy of Conbercept for the treatment of corneal neovascularization (NV) in a rabbit model. METHODS NV was induced by placing sutures. Eight rabbits were used as a control. The other 136 rabbits were randomly divided into two equal groups, and 68 rabbits in each group were divided into four subgroups and given different treatments. Time-course photographs, histological examination, and enzyme-linked immunoassay ELISA analysis for vascular endothelial growth factor were performed at weeks 1, 2, and 3 after injection placement. RESULTS At weeks 1, 2, and 3 after injection placement, there was less expression of corneal NV and VEGF in the conbercept-treated groups than in the saline-treated control groups and less corneal NV and VEGF were expressed in the early treatment group than in the late treatment group. At weeks 2 and 3 after injection, there were fewer corneal NV (length and area) in the early intrastromal injection group with conbercept than in the early subconjunctival injection group with conbercept and a smaller diameter of corneal NV than in the late intrastromal injection group treated with conbercept. Histological examination showed a smaller diameter of corneal NV in all eyes in conbercept-treated groups 1 w after injection than before injection. Treatment with subconjunctival injection with conbercept led to a larger diameter at weeks 2 and 3 than at week 1. CONCLUSIONS Subconjunctival and intrastromal administrations of conbercept effectively inhibit corneal NV in rabbits, and the latter has the better effect. The effect is the best in the group with cornea intrastromal injection of conbercept 1 w after suture. Early administration of conbercept may successfully inhibit corneal NV in an animal model.
Collapse
Affiliation(s)
- Liqun Du
- Dept. Of Ophthalmology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Jiazhang Sun
- Dept. Of Ophthalmology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Jing Liu
- Dept. of Biostatistics, School of Public Health, Shandong University, Jinan, Shandong, China
| | - Na Xu
- Dept. Of Ophthalmology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Mei Liu
- Dept. Of Ophthalmology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Xinyi Wu
- Dept. Of Ophthalmology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| |
Collapse
|
2
|
Peptide Inhibitors of Vascular Endothelial Growth Factor A: Current Situation and Perspectives. Pharmaceutics 2021; 13:pharmaceutics13091337. [PMID: 34575413 PMCID: PMC8467741 DOI: 10.3390/pharmaceutics13091337] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/18/2021] [Accepted: 08/24/2021] [Indexed: 12/11/2022] Open
Abstract
Vascular endothelial growth factors (VEGFs) are the family of extracellular signaling proteins involved in the processes of angiogenesis. VEGFA overexpression and altered regulation of VEGFA signaling pathways lead to pathological angiogenesis, which contributes to the progression of various diseases, such as age-related macular degeneration and cancer. Monoclonal antibodies and decoy receptors have been extensively used in the anti-angiogenic therapies for the neutralization of VEGFA. However, multiple side effects, solubility and aggregation issues, and the involvement of compensatory VEGFA-independent pro-angiogenic mechanisms limit the use of the existing VEGFA inhibitors. Short chemically synthesized VEGFA binding peptides are a promising alternative to these full-length proteins. In this review, we summarize anti-VEGFA peptides identified so far and discuss the molecular basis of their inhibitory activity to highlight their pharmacological potential as anti-angiogenic drugs.
Collapse
|
3
|
Subconjunctival Aflibercept for the Treatment of Formed Corneal Neovascularization. Eye Contact Lens 2021; 47:180-184. [PMID: 32443011 DOI: 10.1097/icl.0000000000000709] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2020] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effect of a single subconjunctival aflibercept injection on formed corneal neovascularization. METHODS A prospective clinical trial, conducted at a single tertiary medical center. Included were consecutive patients with corneal pathologies complicated by corneal neovascularization, who were candidates for anti-vascular endothelial growth factor treatment at the discretion of a cornea specialist. A single subconjunctival injection of 0.08 mL of Aflibercept (Eylea 25 mg/mL) was administered near the limbus in proximity to the areas of maximal pathological neovascularization. Follow-up visits were scheduled on days 7, 30, 60, and 90 following injection. Best-corrected visual acuity (BCVA), intraocular pressure, slitlamp examination, digital cornea photography, specular microscopy, and anterior-segment optical coherence tomography were documented at each visit. The images were graded by a masked observer for density, extent, and centricity of corneal vascularization. RESULTS Six eyes of six patients were analyzed. No clinically significant ocular or systemic adverse events were documented. No change was noted in extent, density, or centricity of corneal blood vessels at seven, 30, and 90 days after injection (P>0.1 for all time point comparisons, Friedman test). Best-corrected visual acuity fluctuated insignificantly in 5/6 patients during follow-up time, and objective but not subjective improvement of BCVA was noted in one patient with no concurrent change of neovascularization. The recruitment has therefore halted prematurely. CONCLUSIONS A single subconjunctival aflibercept injection seems to be well tolerated. However, it is ineffective for regressing formed corneal neovascularization.
Collapse
|
4
|
Shaik F, Cuthbert GA, Homer-Vanniasinkam S, Muench SP, Ponnambalam S, Harrison MA. Structural Basis for Vascular Endothelial Growth Factor Receptor Activation and Implications for Disease Therapy. Biomolecules 2020; 10:biom10121673. [PMID: 33333800 PMCID: PMC7765180 DOI: 10.3390/biom10121673] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/12/2020] [Accepted: 12/13/2020] [Indexed: 12/15/2022] Open
Abstract
Vascular endothelial growth factors (VEGFs) bind to membrane receptors on a wide variety of cells to regulate diverse biological responses. The VEGF-A family member promotes vasculogenesis and angiogenesis, processes which are essential for vascular development and physiology. As angiogenesis can be subverted in many disease states, including tumour development and progression, there is much interest in understanding the mechanistic basis for how VEGF-A regulates cell and tissue function. VEGF-A binds with high affinity to two VEGF receptor tyrosine kinases (VEGFR1, VEGFR2) and with lower affinity to co-receptors called neuropilin-1 and neuropilin-2 (NRP1, NRP2). Here, we use a structural viewpoint to summarise our current knowledge of VEGF-VEGFR activation and signal transduction. As targeting VEGF-VEGFR activation holds much therapeutic promise, we examine the structural basis for anti-angiogenic therapy using small-molecule compounds such as tyrosine kinase inhibitors that block VEGFR activation and downstream signalling. This review provides a rational basis towards reconciling VEGF and VEGFR structure and function in developing new therapeutics for a diverse range of ailments.
Collapse
Affiliation(s)
- Faheem Shaik
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK;
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
- Correspondence: ; Tel.: +44-207-8824207
| | - Gary A. Cuthbert
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK; (G.A.C.); (S.H.-V.); (M.A.H.)
| | | | - Stephen P. Muench
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK;
| | | | - Michael A. Harrison
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK; (G.A.C.); (S.H.-V.); (M.A.H.)
| |
Collapse
|
5
|
Qin Y, Yu Y, Fu J, Xie X, Wang T, Woodward MA, Paulus YM, Yang X, Wang X. Photo-Mediated Ultrasound Therapy for the Treatment of Corneal Neovascularization in Rabbit Eyes. Transl Vis Sci Technol 2020; 9:16. [PMID: 33344060 PMCID: PMC7726583 DOI: 10.1167/tvst.9.13.16] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/24/2020] [Indexed: 12/05/2022] Open
Abstract
Purpose Corneal neovascularization (CNV) is the invasion of new blood vessels into the avascular cornea, leading to reduced corneal transparency and visual acuity, impaired vision, and even blindness. Current treatment options for CNV are limited. We developed a novel treatment method, termed photo-mediated ultrasound therapy (PUT), that combines laser and ultrasound, and we tested its feasibility for treating CNV in a rabbit model. Methods A suture-induced CNV model was established in New Zealand White rabbits, which were randomly divided into two groups: PUT and control. For the PUT group, the applied light fluence at the corneal surface was estimated to be 27 mJ/cm2 at 1064-nm wavelength with a pulse duration of 5 ns, and the ultrasound pressure applied on the cornea was 0.43 MPa at 0.5 MHz. The control group received no treatment. Red-free photography and fluorescein angiography were utilized to evaluate the efficiency of PUT. Safety was evaluated by histology and immunohistochemistry. For comparison with the PUT safety results, conventional laser photocoagulation (LP) treatment was performed with standard clinical parameters: 532-nm continuous-wave (CW) laser with 0.1-second pulse duration, 450-mW power, and 75-µm spot size. Results In the PUT group, only 1.8% ± 0.8% of the CNV remained 30 days after treatment. In contrast, 71.4% ± 7.2% of the CNV remained in the control group after 30 days. Safety evaluations showed that PUT did not cause any damage to the surrounding tissue. Conclusions These results demonstrate that PUT is capable of removing CNV safely and effectively in this rabbit model. Translational Relevance PUT can remove CNV safely and effectively.
Collapse
Affiliation(s)
- Yu Qin
- Institute of Acoustics, School of Physics Science and Engineering, Tongji University, Shanghai, China.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Yixin Yu
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, USA.,Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan Province, China.,Hunan Key Laboratory of Ophthalmology, Changsha, Hunan Province, China
| | - Julia Fu
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Xinyi Xie
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Tao Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Maria A Woodward
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Yannis M Paulus
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.,Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Xinmai Yang
- Institute for Bioengineering Research and Department of Mechanical Engineering, University of Kansas, Lawrence, KS, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
6
|
Prevention of corneal neovascularization by subconjunctival injection of avastin® loaded thermosensitive hydrogels in rabbit model. Int J Pharm 2018; 552:164-170. [PMID: 30217769 DOI: 10.1016/j.ijpharm.2018.09.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/06/2018] [Accepted: 09/10/2018] [Indexed: 12/22/2022]
Abstract
The antibody avastin® (Ava) has been clinically to treat various intraocular neovascular diseases, but suffering from the rapid clearance and short shelf-life of Ava in the requirement of frequent administration. In the present study, we reports the sustained release of Ava from a thermosensitive hydrogel based on poly(ethylene glycol)-poly(ɛ-caprolactone)-poly(ethylene glycol) (PECE) copolymer for the control of corneal neovascularization in rabbit model. Ava were physically mixed with PECE aqueous solution at 4 °C, and resulting Ava-PECE solution showed a sol-gel transition at physiological temperature (37 °C). In vitro release study indicated that Ava-PECE hydrogel provided a sustained release of Ava up to 28 days and the drug release behavior could be finely modulated by the change of PECE concentration. A single subconjunctival injection of PECE hydrogel hardly caused the change of intraocular pressure and corneal endothelial morphology during the entire study period. Intraocular pharmacokinetic analysis suggested that the Ava-PECE hydrogel provided a relatively higher Ava concentration in cornea over Ava solution up to 14 days. In addition, anti-angiogenic effects of the Ava-PECE hydrogel in a suture-induced corneal neovascularization rabbit model indicated that the Ava-PECE hydrogel treatment exhibited superior anti-angiogenic efficacy over Ava solution treatment by decreasing the area ratio of neovascularization on 17 days. Overall, the proposed Ava-PECE hydrogel acting a sustained drug delivery system might be a promising vehicle for the treatment of corneal neovascularization.
Collapse
|