β-adrenergic receptor regulation of pigment epithelial-derived factor expression in rat retina
β-adrenergic receptor regulation of pigment epithelial-derived factor expression in rat retina
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DOI：
10.1016/j.autneu.2005.05.006
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发表时间：
2005-08-31
影响因子：
2.7
通讯作者：
Steinle, JJ
中科院分区：
文献类型：
--
作者：
Lashbrook, BL;Steinle, JJ
在本研究中，我们研究了交感神经调节PEDF的潜在机制，以及其下调是否可能是交感神经切除术后观察到的毛细血管密度增加的原因。交感神经切除术后6周，从雌性Sprague-Dawley大鼠中取出眼睛用于蛋白质印迹分析、RNA分离、实时PCR和免疫组织化学以测量PEDF表达。对侧或左眼用作动物内对照。此外，视网膜色素上皮细胞在培养物中生长，并用去甲肾上腺素和普萘洛尔处理。使用ELISA测定来确定分泌到RPE培养基中的PEDF的量。Western blot分析和实时定量PCR的定量结果证实，与对侧视网膜相比，在交感神经切除的视网膜中，PEDF的稳态基因表达和蛋白水平均显著降低（P < 0.05）。免疫组化的定性结果证实PEDF主要位于视网膜的RPE细胞层中，并且在交感神经切除的视网膜中水平降低。ELISA结果表明，去甲肾上腺素显著增加RPE细胞的PEDF分泌，普萘洛尔轻微减少PEDF分泌到RPE细胞培养基中。总之，PEDF的下调可能有助于交感神经切除术后视网膜外丛状层毛细血管密度的增加。此外，在RPE培养基中去甲肾上腺素处理后，PEDF的表达显著增加，表明PEDF的β-肾上腺素能调节作用。由于交感神经在糖尿病中受损，并且PEDF似乎受β-肾上腺素能受体调节，因此这些结果表明交感神经在糖尿病视网膜病变中的作用。这些知识，反过来，可用于未来的治疗和预防糖尿病视网膜病变和其他眼部疾病。(c)2005 Elsevier B. V.保留所有权利。
In the present study, we have examined a potential mechanism by which sympathetic nerves regulate PEDF and whether its down regulation may be responsible for increased capillary density observed after sympathectomy. Six weeks post-sympathectomy, eyes were removed from female Sprague-Dawley rats for Western blot analysis, RNA isolation, real-time PCR, and immunohistochemistry for measurement of PEDF expression. The contralateral or left eye was used as an intra-animal control. In addition, retinal pigment epithelial cells were grown in culture and treated with norepinephrine and propranolol. An ELISA assay was used to determine the amount of PEDF secreted into the RPE media. Quantitative results of Western blot analysis and real-time PCR confirm that both steady-state gene expression and protein levels of PEDF are significantly decreased in the sympathectomized retina (P < 0.05) when compared to the contralateral retina. Qualitative results of immunohistochemistry verify that PEDF is located predominantly in the RPE cell layer of the retina, and levels are decreased in the sympathectomized retina. ELISA results illustrate that norepinephrine significantly increases PEDF secretion by RPE cells and propranolol slightly decreases PEDF secretion into RPE cell medium. In conclusion, down regulation of PEDF may contribute to the increased capillary density of the outer plexiform layer in the retina noted after sympathectomy. Furthermore, expression of PEDF was significantly increased after treatment of norepinephrine in RPE medium demonstrating a role of beta-adrenergic regulation of PEDF. Since sympathetic nerves are damaged in diabetes and PEDF appears to be regulated by beta-adrenergic receptors, these results suggest a role for sympathetic nerves in diabetic retinopathy. This knowledge, in turn, may be used for future treatment and prevention of diabetic retinopathy and other ocular diseases. (c) 2005 Elsevier B.V. All rights reserved.