Uehara Hironori, Muddana Santosh Kumar, Zhang Xiaohui, Das Subrata Kumar, Bhuvanagiri Sai, Liu Jinlu, Wu Yuanyuan, Choi Susie, Carroll Lara S, Archer Bonnie, Ambati Balamurali K
John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA.
Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Eye Hospital of China Medical University, Shenyang, China.
Transl Vis Sci Technol. 2017 May 24;6(3):9. doi: 10.1167/tvst.6.3.9. eCollection 2017 May.
We previously showed that intravitreal injection of the sFLT morpholino-oligomer (FLT-MO) suppresses laser-induced choroidal neovascularization (CNV) in mice by decreasing the membrane bound form of Flt-1 while increasing the soluble form of Flt-1 via alternative splicing shift. In this study, we examined whether cyclic RGD peptide (cRGD) can promote morpholino-oligomer accumulation in CNV following tail vein injection, and whether systemic cRGD conjugated FLT-MO (cRGD-FLT-MO) suppresses CNV growth.
cRGD conjugated fluorescent morpholino-oligomer (cRGD-F-MO) was injected via tail vein into mice with previous retinal laser photocoagulation and examined for cRGD-F-MO accumulation in CNV. To examine whether cRGD-FLT-MO suppresses CNV growth, mice were tail-vein injected with cRGD-FLT-MO, cRGD conjugated standard morpholino-oligomer (cRGD-STD-MO), or Dulbecco's Phosphate-Buffered Saline (DPBS) 1 and 4 days postlaser photocoagulation. Seven days postlaser photocoagulation, eyes were harvested and laser CNV was stained with isolectin GS-IB4, allowing quantification of CNV size by confocal microscopy.
cRGD-F-MO accumulation in CNV commenced immediately after tail vein injection and could be observed even 1 day after injection. cRGD-FLT-MO tail vein injection significantly suppressed CNV size (2.7 × 10 ± 0.3 × 10 μm, < 0.05 by Student's -test) compared with controls (DPBS: 5.1 × 10 ± 0.6 × 10 μm and cRGD-STD-MO: 5.5 × 10 ± 0.8 × 10 μm).
cRGD peptide facilitates morpholino-oligomer accumulation in CNV following systemic delivery. cRGD-FLT-MO suppressed CNV growth after tail-vein injection, demonstrating the potential utility of cRGD peptide for morpholino-oligomer delivery to CNV.
Current therapy for neovascular age-related macular degeneration involves intravitreal injection of anti-vascular endothelial growth factor drugs. Our results indicate that CNV can be treated systemically, thus eliminating risks and hazards associated with intravitreal injection.
我们之前的研究表明，玻璃体内注射可溶性血管内皮生长因子受体1吗啉代寡聚物（FLT-MO）可通过减少Flt-1的膜结合形式、同时通过可变剪接转变增加Flt-1的可溶性形式，从而抑制小鼠激光诱导的脉络膜新生血管形成（CNV）。在本研究中，我们检测了环RGD肽（cRGD）在尾静脉注射后是否能促进吗啉代寡聚物在CNV中的蓄积，以及全身性cRGD偶联的FLT-MO（cRGD-FLT-MO）是否能抑制CNV生长。
将cRGD偶联的荧光吗啉代寡聚物（cRGD-F-MO）经尾静脉注射到先前已进行视网膜激光光凝的小鼠体内，并检测CNV中cRGD-F-MO的蓄积情况。为检测cRGD-FLT-MO是否能抑制CNV生长，在激光光凝后1天和4天，经尾静脉给小鼠注射cRGD-FLT-MO、cRGD偶联的标准吗啉代寡聚物（cRGD-STD-MO）或杜氏磷酸盐缓冲盐水（DPBS）。激光光凝后7天，摘取眼球，用异凝集素GS-IB4对激光诱导的CNV进行染色，通过共聚焦显微镜对CNV大小进行定量分析。
尾静脉注射后，cRGD-F-MO立即开始在CNV中蓄积，甚至在注射后1天仍可观察到。与对照组（DPBS：5.1×10±0.6×10μm和cRGD-STD-MO：5.5×10±0.8×10μm）相比，尾静脉注射cRGD-FLT-MO可显著抑制CNV大小（2.7×10±0.3×10μm，Student's t检验，P<0.05）。
cRGD肽在全身性给药后可促进吗啉代寡聚物在CNV中的蓄积。尾静脉注射cRGD-FLT-MO可抑制CNV生长，证明了cRGD肽在将吗啉代寡聚物递送至CNV方面的潜在应用价值。
目前针对新生血管性年龄相关性黄斑变性的治疗方法包括玻璃体内注射抗血管内皮生长因子药物。我们的结果表明，CNV可以通过全身治疗，从而消除与玻璃体内注射相关的风险和危害。
