Rezzola Sara, Corsini Michela, Chiodelli Paola, Cancarini Anna, Nawaz Imtiaz M, Coltrini Daniela, Mitola Stefania, Ronca Roberto, Belleri Mirella, Lista Liliana, Rusciano Dario, De Rosa Mario, Pavone Vincenzo, Semeraro Francesco, Presta Marco
Department of Molecular and Translational Medicine, University of Brescia, Via Branze 39, Brescia, 25123, Italy.
Department of Ophthalmology, University of Brescia, Piazzale Spedali Civili 1, Brescia, 25123, Italy.
Diabetologia. 2017 Apr;60(4):719-728. doi: 10.1007/s00125-016-4204-0. Epub 2017 Jan 13.
AIMS/HYPOTHESIS: Angiogenesis and inflammation characterise proliferative diabetic retinopathy (PDR), a major complication of diabetes mellitus. However, the impact of inflammation on the pathogenesis of PDR neovascularisation has not been elucidated. Here, we assessed the capacity of PDR vitreous fluid to induce pro-angiogenic/proinflammatory responses in endothelium and the contribution of the inflammation-related pattern recognition N-formyl peptide receptors (FPRs) in mediating these responses.
Pooled and individual pars plana vitrectomy-derived PDR vitreous fluid ('PDR vitreous') samples were assessed in endothelial cell proliferation, motility, sprouting and morphogenesis assays, and for the capacity to induce proinflammatory transcription factor activation, reactive oxygen species production, intercellular junction disruption and leucocyte-adhesion molecule upregulation in these cells. In vivo, the pro-angiogenic/proinflammatory activity of PDR vitreous was tested in murine Matrigel plug and chick embryo chorioallantoic membrane (CAM) assays. Finally, the FPR inhibitors Boc-Phe-Leu-Phe-Leu-Phe (Boc-FLFLF) and Ac-L-Arg-Aib-L-Arg-L-Cα(Me)Phe-NH tetrapeptide (UPARANT) were evaluated for their capacity to affect the biological responses elicited by PDR vitreous.
PDR vitreous activates a pro-angiogenic/proinflammatory phenotype in endothelial cells. Accordingly, PDR vitreous triggers a potent angiogenic/inflammatory response in vivo. Notably, the different capacity of individual PDR vitreous samples to induce neovessel formation in the CAM correlates with their ability to recruit infiltrating CD45 cells. Finally, the FPR inhibitor Boc-FLFLF and the novel FPR antagonist UPARANT inhibit neovessel formation and inflammatory responses triggered by PDR vitreous in the CAM assay.
CONCLUSIONS/INTERPRETATION: This study provides evidence that inflammation mediates the angiogenic activity of PDR vitreous and paves the way for the development of FPR-targeting anti-inflammatory/anti-angiogenic approaches for PDR therapy.
目的/假设：血管生成和炎症是增殖性糖尿病视网膜病变（PDR）的特征，PDR是糖尿病的一种主要并发症。然而，炎症对PDR新生血管形成发病机制的影响尚未阐明。在此，我们评估了PDR玻璃体液诱导内皮细胞促血管生成/促炎反应的能力，以及炎症相关模式识别N-甲酰肽受体（FPRs）在介导这些反应中的作用。
对合并的以及个体经扁平部玻璃体切割术获得的PDR玻璃体液（“PDR玻璃体”）样本进行评估，检测其在内皮细胞增殖、迁移、芽生和形态发生试验中的作用，以及诱导这些细胞中促炎转录因子激活、活性氧产生、细胞间连接破坏和白细胞粘附分子上调的能力。在体内，通过小鼠基质胶栓塞和鸡胚绒毛尿囊膜（CAM）试验检测PDR玻璃体的促血管生成/促炎活性。最后，评估FPR抑制剂Boc-Phe-Leu-Phe-Leu-Phe（Boc-FLFLF）和Ac-L-Arg-Aib-L-Arg-L-Cα（Me）Phe-NH四肽（UPARANT）影响PDR玻璃体引发的生物学反应的能力。
PDR玻璃体激活内皮细胞中的促血管生成/促炎表型。相应地，PDR玻璃体在体内引发强烈的血管生成/炎症反应。值得注意的是，各个PDR玻璃体样本在CAM中诱导新血管形成的不同能力与其募集浸润性CD45细胞的能力相关。最后，FPR抑制剂Boc-FLFLF和新型FPR拮抗剂UPARANT在CAM试验中抑制PDR玻璃体引发的新血管形成和炎症反应。
结论/解读：本研究提供了证据，证明炎症介导PDR玻璃体的血管生成活性，并为开发针对FPR的抗炎/抗血管生成方法用于PDR治疗铺平了道路。
