To investigate biometric and refractive results in patients with type 1 retinopathy of prematurity (ROP) treated by intravitreal injection (IVI) of ranibizumab (R) and bevacizumab (B) at the corrected age of 6. This is a single-center retrospective study. Infants diagnosed with type 1 ROP and treated with IVI of either R or B as the primary therapy were included. Data on axial length, anterior chamber depth (ACD), and lens thickness (LT) were obtained using A-scan ultrasound. Cycloplegic refraction, keratometry (K), and best-corrected visual acuity were also documented. Additionally, optical coherence tomography angiography was performed to assess the foveal avascular zone and the density of superficial and deep vessels. We analyzed the structural and functional differences between the 2 groups and compared them with findings from a previous study conducted when these children were between the ages of 1 and 3. The study included 60 eyes from 34 patients, with 34 eyes receiving B and 26 eyes receiving R injections for ROP. In biometric outcomes, there was still a deeper ACD (3.36 ± 0.24 mm in the B group; 3.52 ± 0.21 mm in the R group) and thinner LT (3.63 ± 0.16 mm in the B group; 3.53 ± 0.12 mm in the R group) in the R group, as previously reported at the age of 3. In the refractive aspect, the eyes treated with B had higher myopia at the ages of 1 and 3; however, at the age of 6, refractive errors did not differ significantly between the 2 groups. At the corrected age of 6, the eyes treated with IVI of R were associated with deeper ACD and thinner LT. Interestingly, the emmetropization process resulted in a similar incidence of high myopia at the age of 6, which was different from the outcomes observed at younger ages.

UNASSIGNED: Melatonin has promising protective effects for retinopathy. However, its roles in retinopathy of prematurity (ROP) and the underlying mechanisms remain unknown. We aimed to explore its roles and mechanisms in a ROP model.
UNASSIGNED: Hematoxylin and eosin staining were used to observe the morphology of the retina. Immunofluorescence was used to detect positive (Nrf2+ and VEGF+) cells. Immunohistochemistry was used to detect the level of nuclear expression of PCNA in retinal tissue. Transmission electron microscope (TEM) was used to observe the morphology and structure of pigment cells. qRT-PCR was used to assay the expression of miR-23a-3p, Nrf2, and HO-1. Western blotting was used to detect the expression of Nrf2, HO-1, β-actin, and Lamin B1.
UNASSIGNED: Melatonin or miR-23a-3p antagomir treatment could ameliorate the Oxygen-induced pathological changes, increased the expression of Nrf2 and HO-1, SOD, and GSH-Px, and decreased the expression of VEGF, miR-23a-3p, MDA and the apoptosis in the ROP model. Further target prediction and luciferase reporter assays confirmed the targeted binding relationship between miR-23a-3p and Nrf2.
UNASSIGNED: Our study showed that melatonin could ameliorate H2O2-induced apoptosis and oxidative stress injury in RGC cells by mediating miR-23a-3p/Nrf2 signaling pathway, thereby improving retinal degeneration.

BACKGROUND: Early prediction and timely treatment are essential for minimizing the risk of visual loss or blindness of retinopathy of prematurity, emphasizing the importance of ROP screening in clinical routine.
OBJECTIVE: To establish predictive models for ROP occurrence based on the risk factors using artificial neural network.
METHODS: A cohort of 591 infants was recruited in this retrospective study. The association between ROP and perinatal factors was analyzed by univariate analysis and multivariable logistic regression. We developed predictive models for ROP screening using back propagation neural network, which was further optimized by applying genetic algorithm method. To assess the predictive performance of the models, the areas under the curve, sensitivity, specificity, negative predictive value, positive predictive value and accuracy were used to show the performances of the prediction models.
RESULTS: ROP of any stage was found in 193 (32.7%) infants. Twelve risk factors of ROP were selected. Based on these factors, predictive models were built using BP neural network and genetic algorithm-back propagation (GA-BP) neural network. The areas under the curve for prediction models were 0.857, and 0.908 in test, respectively.
CONCLUSIONS: We developed predictive models for ROP using artificial neural network. GA-BP neural network exhibited superior predictive ability for ROP when dealing with its non-linear clinical data.

OBJECTIVE: Pathological retinal neovascularization is vision-threatening. In mouse oxygen-induced retinopathy (OIR) we sought to define mitochondrial respiration changes longitudinally during hyperoxia-induced vessel loss and hypoxia-induced neovascularization, and to test interventions addressing those changes to prevent neovascularization.
METHODS: OIR was induced in C57BL/6J mice and retinal vasculature was examined at maximum neovessel formation. We assessed total proteome changes and the ratio of mitochondrial to nuclear DNA copy numbers (mtDNA/nDNA) of OIR vs. control retinas, and mitochondrial oxygen consumption rates (OCR) in ex vivo OIR vs. control retinas (BaroFuse). Pyruvate vs. vehicle control was supplemented to OIR mice either prior to or during neovessel formation.
RESULTS: In OIR vs. control retinas, global proteomics showed decreased retinal mitochondrial respiration at peak neovascularization. OCR and mtDNA/nDNA were also decreased at peak neovascularization suggesting impaired mitochondrial respiration. In vivo pyruvate administration during but not prior to neovessel formation (in line with mitochondrial activity time course) suppressed NV.
CONCLUSIONS: Mitochondrial energetics were suppressed during retinal NV in OIR. Appropriately timed supplementation of pyruvate may be a novel approach in neovascular retinal diseases.

BACKGROUND: Ocular neovascular diseases, which contribute significantly to vision loss, lack effective preventive treatments. Recent studies have highlighted the significant involvement of immune cells in neovascular retinopathy. Myeloid-derived suppressor cells (MDSCs) promote the development of neovascularization, but it is unknown whether they participate in pathological neovascularization and whether they are expected to be a therapeutic target.
METHODS: We investigated the role of MDSCs in promoting pathological angiogenesis using an oxygen-induced retinopathy (OIR) model, employing flow cytometry, immunofluorescence, and smart-seq analysis. Then, we evaluated the proportion of MDSCs in patient blood samples using flow cytometry. Additionally, we assessed the effect of MDSC depletion using an anti-Gr-1 monoclonal antibody on retinal vasculopathy and alterations in retinal microglia.
RESULTS: In the OIR model, an elevated ratio of MDSCs was observed in both blood and retinal tissue during phase II (Neovascularization). The depletion of MDSCs resulted in reduced retinal neovascularization and vaso-obliteration, along with a decrease in microglia within the neovascularization area. Furthermore, analysis of gene transcripts associated with MDSCs indicated activation of vascular endothelial growth factor (VEGF) regulation and inflammation. Importantly, infants with ROP exhibited a higher proportion of MDSCs in their blood samples.
CONCLUSIONS: Our results suggested that excessive MDSCs represent an unrecognized feature of ocular neovascular diseases and be responsible for the retinal vascular inflammation and angiogenesis, providing opportunities for new therapeutic approaches to ocular neovascular disease.

Retinopathy of prematurity (ROP) is a retinal neovascularization (RNV) disease that is characterized by abnormal blood vessel development in the retina. Importantly, the etiology of ROP remains understudied. We re-analyzed previously published single-cell data and discovered a strong correlation between microglia and RNV diseases, particularly ROP. Subsequently, we found that reactive oxygen species reduced autophagy-dependent protein degradation of absent in melanoma 2 (AIM2) in hypoxic BV2 cells, leading to increased AIM2 protein accumulation. Furthermore, we engineered AIM2 knockout mice and observed that the RNV was significantly reduced compared to wild-type mice. In vitro vascular function assays also demonstrated diminished angiogenic capabilities following AIM2 knockdown in hypoxic BV2 cells. Mechanistically, AIM2 enhanced the M1-type polarization of microglia via the ASC/CASP1/IL-1β pathway, resulting in RNV. Notably, the administration of recombinant protein IL-1β exacerbated angiogenesis, while its inhibition ameliorated the condition. Taken together, our study provides a novel therapeutic target for ROP and offers insight into the interaction between pyroptosis and autophagy.

OBJECTIVE: To observe the effect of human umbilical cord mesenchymal stem cells (hUCMSCs) secretions on the relevant factors in mouse retinal astrocytes, and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A (VEGF-A) and to observe the therapeutic effect on the mouse model of retinopathy of prematurity (ROP).
METHODS: Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia group. MTT assay, flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect related indicators. Possible mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were explored. At last, the efficacy of exosomes of UCMSCs in a mouse ROP model was explored. Graphpad6 was used to comprehensively process data information.
RESULTS: The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient ultracentrifugation. Reactive oxygen species (ROS) and hypoxia inducible factor-1α (HIF-1α) of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased, and the ROP cell model was established after 6h of hypoxia. The secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α, the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration dependent. Compared with the ROP cell model group, the expression of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signal pathway related factors in the hUCMSCs exocrine group is significantly decreased. The intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1α in ROP model tissues. HE staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs secretion.
CONCLUSIONS: In a hypoxia induced mouse retinal astrocyte model, hUCMSCs exosomes are found to effectively reduce the expression of HIF-1α and VEGF-A, which are positively correlated with the concentration of hUCMSCs exosomes. HUCMSCs exosomes can effectively reduce the number of retinal neovascularization and the expression of HIF-1α and VEGF-A proteins in ROP mice, and are positively correlated with drug dosage. Besides, they can reduce the related factors on the PI3K/AKT/mTOR signaling pathway.

BACKGROUND: Retinopathy of Prematurity (ROP) is a proliferative retinal vascular disease occurring in the retina of premature infants and is the main cause of childhood blindness. Nowadays anti-VEGF and retinal photocoagulation are mainstream treatments for ROP, but they develop a variety of complications. Hydrogen (H2) is widely considered as a useful neuroprotective and antioxidative therapeutic method for hypoxic-ischemic disease without toxic effects. However, whether H2 provides physiological angiogenesis promotion, neovascularization suppression and glial protection in the progression of ROP is largely unknown.This study aims to investigate the effects of H2 on retinal angiogenesis, neovascularization and neuroglial dysfunction in the retinas of oxygen-induced retinopathy (OIR) mice.
METHODS: In this study, mice that were seven days old and either wild-type (WT) or Nrf2-deficient (Nrf2-/-) were exposed to 75% oxygen for 5 days and then returned to normal air conditions. Different stages of hydrogen gas (H2) inhalation were administered. Vascular obliteration, neovascularization, and blood vessel leakage were analyzed and compared. To count the number of neovascularization endothelial nuclei, routine HE staining of retinal sections was conducted. Immunohistochemistry was performed using DyLight 594 labeled GSL I-isolectin B4 (IB4), as well as primary antibodies against proliferating cell nuclear antigen (PCNA), glial fibrillary acidic protein (GFAP), and Iba-1. Western blots were used to measure the expression of NF-E2-related factor 2 (Nrf2), vascular endothelial growth factor (VEGF), Notch1, Dll4, and HIF-1α. Additionally, the expression of target genes such as NQO1, HO-1, Notch1, Hey1, Hey2, and Dll4 was measured. Human umbilical vein endothelial cells (HUVECs) treated with H2 under hypoxia were used as an in vitro model. RT-PCR was used to evaluate the mRNA expression of Nrf2, Notch/Dll4, and the target genes. The expression of reactive oxygen species (ROS) was observed using immunofluorescence staining.
RESULTS: Our results indicate that 3-4% H2 does not disturb retinal physiological angiogenesis, but ameliorates vaso-obliteration and neovascularization in OIR mice. Moreover, H2 prevents the decreased density and reverses the morphologic and functional changes in retinal astrocytes caused by oxygen-induced injury. In addition, H2 inhalation reduces microglial activation, especially in the area of neovascularization in OIR mice. H2 plays a protective role in vascular regeneration by promoting Nrf2 activation and suppressing the Dll4-induced Notch signaling pathway in vivo. Also, H2 promotes the proliferation of HUVECs under hypoxia by negatively regulating the Dll4/Notch pathway and reducing ROS levels through Nrf2 pathway aligning with our findings in vivo.Moreover, the retinal oxygen-sensing mechanisms (HIF-1α/VEGF) are also involved in hydrogen-mediated retinal revascularization and neovascularization suppression.
CONCLUSIONS: Collectively, our results indicate that H2 could be a promising therapeutic agent for POR treatment and that its beneficial effect in human ROP might involve the activation of the Nrf2-Notch axis as well as HIF-1α/VEGF pathways.

Retinopathy of prematurity (ROP) is a retinopathy caused by abnormal proliferation of blood vessels in premature infants. It can lead to retinal detachment and, in severe cases, blindness, rendering ROP a critical condition. Advances in neonatal medicine have improved survival rates of low birth weight and low gestational age infants. However, this progress has also led to a rise in incidence of ROP. Currently, premature birth, low birth weight and high postpartum oxygen levels are independent risk factors for ROP. Other factors include mode of delivery, multiple births, anemia, blood transfusion, maternal pregnancy factors, neonatal bronchopulmonary dysplasia, use of surfactants, arterial ductus arteriosus and necrotizing enterocolitis. Laboratory indicators in premature infants such as platelet count, levels of blood glucose, inflammatory cells, lipid and hemoglobin and blood transfusion may also be associated with ROP. However, the etiology and pathogenesis of ROP are not fully understood. A number of factors may influence the onset and progression of ROP, including decreased platelet counts, decreased hemoglobin levels, increased white blood cell counts, increased blood glucose levels, and disorders of lipid metabolism. The present study reviewed the effects of platelet count, hemoglobin, blood glucose, inflammatory cells and factors, blood lipids, and plasma metabolic pathways on ROP.

BACKGROUND: Oculocutaneous albinism (OCA) is a group of autosomal recessive hereditary disorders that affect melanin biosynthesis, resulting in abnormalities in hair, skin, and eyes. Retinopathy of prematurity (ROP) is a proliferative retinopathy mainly observed in premature infants with low birth weight and early gestational age, but it can also affect full-term infants or children with normal weight, particularly in developing countries. The coexistence of ROP and OCA is rare. There is limited documentation regarding treatment approaches, with few studies reporting positive outcomes with laser treatment due to the absence of melanin pigment. This study discusses the treatment challenges in a female infant diagnosed with ROP and OCA, and underscores the importance of genetic analysis in guiding therapeutic decisions for this rare comorbid condition.
METHODS: The study presents a case of ROP occurring concurrently with OCA. Genetic testing revealed two variants, c.727C > T (p.R243C) and c.1832 T > C (p.L611P), in the OCA2 gene, inherited from the patient\'s mother and father, respectively. The identified mutations were consistent with a diagnosis of OCA2, classified as a subtype of OCA. The patient initially received intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection, followed by laser photocoagulation therapy for a recurrent event. A favorable outcome was observed during the 2-month follow-up period.
CONCLUSIONS: The co-occurrence of ROP and OCA is a rare phenomenon, and this is the first recorded case in the Chinese population. The current case supports the use of laser as the primary treatment modality for ROP in OCA2 patients with partial pigmentation impairment. Furthermore, genetic analysis can aid in predicting the effectiveness of laser photocoagulation in this patient population.