Melatonin attenuated retinal neovascularization and neuroglial dysfunction by inhibition of HIF‐1α‐VEGF pathway in oxygen‐induced retinopathy mice

Retinopathy of prematurity (ROP) is a retinopathy characterized by retinal neovascularization (RNV) occurring in preterm infants treated with high concentrations of oxygen and may lead to blindness in severe cases. Currently, anti‐VEGF therapy is a major treatment for ROP, but it is costly and may cause serious complications. The previous study has demonstrated that melatonin exerted neuroprotective effect against retinal ganglion cell death induced by hypoxia in neonatal rats. However, whether melatonin is anti‐angiogenic and neuroglial protective in the progression of ROP remains unknown. Thus, this study was to investigate the effect of melatonin on RNV and neuroglia in the retina of oxygen‐induced retinopathy (OIR) mice. The results showed a reduction in retinal vascular leakage in OIR mice after melatonin treatment. Besides, the size of retinal neovascular and avascular areas, the number of preretinal neovascular cell nuclei, and the number of proliferative vascular endothelial cells within the neovascular area were significantly decreased in mice treated with melatonin. After oxygen‐induced injury, the density of astrocytes was decreased, accompanied by morphologic and functional changes of astrocytes. Besides, retinal microglia were also activated. Meanwhile, the levels of inflammatory factors were elevated. However, these pathologic processes were all hindered by melatonin treatment. Furthermore, HIF‐1α‐VEGF pathway was activated in the retina of OIR mice, yet was suppressed in melatonin‐treated OIR mice retinas. In conclusion, melatonin prevented pathologic neovascularization, protected neuroglial cells, and exerts anti‐inflammation effect via inhibition of HIF‐1α‐VEGF pathway in OIR retinas, suggesting that melatonin could be a promising therapeutic agent for ROP.     

RetCam与BIO在ROP筛查中的应用效果对比

目的：比较广角数码视网膜成像系统(RetCam)与双目间接检眼镜(BIO)在早产儿视网膜病变(ROP)筛查中的应用效果。

方法：对2014-05/2017-05在我院出生的1 624例3 248眼早产儿进行RetCam与BIO检查，对比两种检查方法对ROP的筛查结果及不良事件发生情况。

结果：早产儿1 624例3 248眼中，RetCam检出ROP患儿196例392眼，BIO检出ROP患儿189例378眼，二者的分期结果与分区病变结果比较差异无统计学意义(P>0.05)； 以BIO检查结果为标准，RetCam检查的敏感性、特异性、假阳性率、阳性预测值分别为100.00%、99.51%、3.57%、96.43%； RetCam与BIO的不良事件发生率分别为0.18%、0.22%，差异无统计学意义(P>0.05)。

结论：RetCam与BIO筛查ROP具有较高一致性，RetCam可以替代BIO作为ROP的筛查方法。     

【In Press】 Protective effect of pomegranate juice on retinal oxidative stress in streptozotocin-induced diabetic rats

AIM: To investigate the effect of pomegranate juice (PJ) intake on overall oxidation status in retinas of diabetic rats. METHODS: Twenty-seven rats were divided into four groups as control (CO), diabetic (DM), control treated with PC (CO-PJ), and diabetic treated with PJ (DM-PJ).The retina tissues were used to determine 8-Hydroxy-2’-deoxyguanosine (8OHdG), malondialdehyde (MDA), reduced glutathione (GSH) levels, and the enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). RESULTS: The levels of 8OHdG and MDA were significantly increased in the retina of DM group compared to CO group (p=0.001, p<0.001 respectively). Both 8OHdG and MDA levels were decreased in PJ-DM group compared to DM group (p=0.004, p<0.001 respectively). The activities of antioxidant enzymes GSH, SOD, and GDH-Px were significantly decreased in the retina of DM group compared to CO group (p≤0.01). GSH and GSH-Px activities were higher in PJ-DM group compared with DM group (p=0.010, p=0.042, respectively) but SOD activity was not statistically different (p=0.938). CONCLUSION: PJ intake was found to be effective in decreasing oxidative end products, and in increasing the activities of antioxidant enzymes in diabetic retinas of rats, which suggests it may be effective against oxidative stress in diabetic retinas.     

Drug,delivery and devices for diabetic retinopathy (3Ds in DR)

ABSTRACT

Introduction: Diabetic Retinopathy (DR) is one of the most common causes of blindness among the working population worldwide. Clearly, there is an unmet clinical need to find better treatment options for DR.

Areas covered: The literature search was conducted on PubMed with no limitation on language or year of publication. The review focuses on the clinically used drugs/proteins along with a brief background on the pathophysiology of DR. The major focus of this review revolves around three treatment approaches involving drugs/proteins, drug delivery formulations and drug delivery devices. In each category, major advances are discussed along with the possible solutions. We have also discussed the various modes of administration that are currently being evaluated in the clinic. An attempt has been made to address the potential targeted site of action for DR drug delivery, and also to understand the role of Blood Retinal Barrier (BRB).

Expert Opinion: In the current scenario, although there have been some advances in the drug delivery devices for delivering drugs/proteins, there are still challenges to be overcome with regard to the particulate systems. For long-term success of DR therapeutics, research options should consider taking into account the 3Ds (drug, delivery and devices).     

人工智能在眼科疾病诊疗的应用现状

近年来，人工智能（artificial intelligence，AI）在医学领域的应用范围不断扩大，已成为医疗行业关注的焦点，在心血管疾病、乳腺癌、皮肤癌、糖尿病视网膜病变、白内障、青光眼及早产儿视网膜病变等诊疗中均有新进展。本综述旨在了解AI在眼科领域的应用现状、优势、进展及不足，为AI在眼科领域的进一步应用及推广提供更多信息。     

Results of intravitreal ranibizumab treatment for retinopathy of prematurity in infants

Purpose: To assess the results of intravitreal ranibizumab treatment for retinopathy of prematurity (ROP) in infants.

Methods: A single-institution, retrospective consecutive case series.

Results: Thirty-one patients who received ranibizumab treatment for ROP were evaluated in this study. The mean follow-up time was 14?±?1.37?months. Vascularization of the peripheral retina had completed with delay in the majority of cases and also avascular areas were present in the peripheral retinas of five infants at one year of age. Although recurrence of ROP developed in 14 infants after single-dose ranibizumab treatment, only four infants received additional treatment due to recurrence of ROP requiring treatment. No serious ocular complications were reported, but, two infants died in this series.

Conclusion: Even so ranibizumab treatment is an effective therapy for ROP in early period, close monitoring after injection is necessary due to the high incidence of recurrence. In addition, questions remain regarding the systemic safety of ranibizumab. Further studies are needed to study the systemic and ocular side effects of ranibizumab.