Fang Yanhong, Wang Qionghua, Li Youjian, Zeng Li, Liu Jian, Ou Kepeng
Department of Ophthalmology, Chongqing University Jiangjin Hospital, Chongqing, China.
College of Pharmacy, National & Local Joint Engineering Research Center of Targeted and Innovative Therapeutics, IATTI, Chongqing University of Arts and Sciences, Chongqing, China.
Neural Regen Res. 2024 Sep 1;19(9):1984-1990. doi: 10.4103/1673-5374.390955. Epub 2023 Dec 15.
Somatostatin, a naturally produced neuroprotective peptide, depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina. In this review, we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar databases. Insufficient neuroprotection, which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy, triggers retinal neurovascular unit impairment and microvascular damage. Somatostatin replacement is a promising treatment for retinal neurodegeneration in diabetic retinopathy. Numerous pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been initiated. In one such trial (EUROCONDOR), topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction, but had no impact on the onset of diabetic retinopathy. Overall, we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage retinopathy. In order to achieve early prevention of diabetic retinopathy initiation, and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy, several issues need to be addressed. These include the needs to: a) update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration, b) identify patient subgroups who would benefit from somatostatin analog supplementation, c) elucidate the interactions of somatostatin, particularly exogenously-delivered somatostatin analogs, with other retinal peptides in the context of hyperglycemia, and d) design safe, feasible, low cost, and effective administration routes.
生长抑素是一种天然产生的神经保护肽，可抑制兴奋性神经传递，并对视网膜发挥抗增殖和抗炎作用。在本综述中，我们通过分析从PubMed和谷歌学术数据库中提取的2019年2月至2023年2月发表的相关研究，总结了生长抑素治疗糖尿病性视网膜病变的进展。在糖尿病性视网膜病变的早期阶段，由于视网膜生长抑素表达下降或失调而导致的神经保护不足，会引发视网膜神经血管单元损伤和微血管损伤。生长抑素替代疗法是治疗糖尿病性视网膜病变中视网膜神经变性的一种有前景的治疗方法。已经启动了许多关于生长抑素类似物治疗早期糖尿病性视网膜病变的临床前和临床试验。在一项此类试验（EUROCONDOR）中，发现局部应用生长抑素对已有视网膜神经功能障碍的患者具有神经保护作用，但对糖尿病性视网膜病变的发病没有影响。总体而言，我们得出结论，生长抑素恢复可能对越来越多的早期视网膜病变患者特别有益。为了实现糖尿病性视网膜病变发病的早期预防，从而在中度非增殖性糖尿病性视网膜病变出现之前挽救视力功能，需要解决几个问题。这些问题包括：a）更新和标准化视网膜筛查方案，以纳入早期神经变性的检测；b）确定将从生长抑素类似物补充中受益的患者亚组；c）阐明生长抑素，特别是外源性递送的生长抑素类似物，在高血糖情况下与其他视网膜肽的相互作用；d）设计安全、可行、低成本且有效的给药途径。
