Gene expression profile of the murine ischemic retina and its response to Aflibercept (VEGF-Trap)

Comparison of ranibizumab and conbercept treatment in type 1 prethreshold retinopathy of prematurity in zone II

PURPOSE

The treatment with anti-VEGF for Retinopathy of prematurity (ROP) has already been widely applied in clinics even though there are still many concerns about this treatment. In this project we investigated the clinical outcomes of intra-vitreous conbercept (IVC) and ranibizumab (IVR) injection for treating type 1 prethreshold ROP in Zone II.

METHODS

The data of ROP infants receiving IVR or IVC from January 2017 to March 2020 who were followed up for at least 12 months in our hospital was studied in the present retrospective study. Regression, reactivation, complications, and ocular biological parameters were evaluated.

RESULTS

One hundred twenty-five eyes (64 infants) in IVC group and 229 eyes (117 infants) in IVR group were observed in the study. All infants showed good response to the two anti-VEGF agents. No eyes deteriorated during the observation. No significant difference was found between the two groups as to the regression within one week and one month, the reactivation rate, and the retreatment interval (p > 0.05) whereas retinal complete vascularization rate at 6 mons after the initial treatment and mean completion time of retinal vascularization after initial injection showed significant difference (p < 0.05). At 12 mons PMA the ocular parameters also presented no statistical difference between the two treated groups (p > 0.05). However, the ocular showed slight myopic tendency with the anti-VEGF treatment when compared to the control group (p < 0.05) whereas there was no statistical difference revealed between the two treated groups (p > 0.05).

CONCLUSIONS

Both conbercept and ranibizumab for treating type 1 prethreshold ROP in Zone II are safe and effective. They had little effect on the development of ocular whereas there was a slight tendency of myopia after the treatment.

Exploring Current Molecular Targets in the Treatment of Neovascular Age-Related Macular Degeneration toward the Perspective of Long-Term Agents

Long-lasting anti-vascular endothelial growth factor (anti-VEGF) agents have become an option to reduce treatment frequency, with ongoing research exploring optimal responses and safety profiles. This review delves into molecular targets, pharmacological aspects, and strategies for achieving effective and enduring disease control in neovascular age-related macular degeneration (AMD). The molecular pathways involved in macular neovascularization, including angiogenesis and arteriogenesis, are explored. VEGF, PlGF, Ang-1, and Ang-2 play crucial roles in regulating angiogenesis, influencing vessel growth, maturation, and stability. The complex interplay of these factors, along with growth factors like TGFβ and bFGF, contributes to the pathogenesis of neovascular membranes. Current anti-VEGF therapies, including bevacizumab, ranibizumab, aflibercept, brolucizumab, and faricimab, are discussed with a focus on their pharmacokinetics and clinical applications. Strategies to achieve sustained disease control in AMD involve smaller molecules, increased drug dosages, and novel formulations. This narrative review provides a comprehensive overview of the molecular targets and pharmacological aspects of neovascular AMD treatment.

Aflibercept Suppression of angiopoietin-2 in a Rabbit Retinal Vascular Hyperpermeability Model

Purpose

Anti-vascular endothelial growth factor (anti-VEGF) therapies, which attenuate the capacity of VEGF to bind to VEGF receptors, are standard-of-care options for various retinal disorders that are characterized by pathologic retinal angiogenesis and vascular permeability. Multiple receptors and ligands have also been reported as being involved in these pathways, including angiopoietin-1 (ANG1) and angiopoietin-2 (ANG2).

Methods

Electrochemiluminescence immunoassays were used to detect human VEGF (hVEGF), as well as rabbit ANG2 and basic fibroblast growth factor protein levels in vitreous samples derived from a study evaluating the efficacy of the anti-VEGF agents ranibizumab, aflibercept, and brolucizumab in an hVEGF165-induced rabbit retinal vascular hyperpermeability model.

Results

hVEGF was completely suppressed in rabbit vitreous after anti-VEGF treatment for 28 days. ANG2 protein in vitreous and ANGPT2 mRNA in retina tissue were similarly suppressed, although the anti-VEGF agents do not directly bind to ANG2. Aflibercept demonstrated the greatest inhibitory effect in ANG2 levels in vitreous, which correlated with strong, durable suppression of intraocular hVEGF levels.

Conclusions

This study explored the effects of anti-VEGF therapies beyond direct binding of VEGF by evaluating protein levels and the expression of target genes involved in angiogenesis and associated molecular mechanisms in the rabbit retina and choroid.

Translational Relevance

In vivo data suggest that anti-VEGF agents currently used for the treatment of retinal diseases could provide beneficial effects beyond direct binding of VEGF, including suppression of ANG2 protein and ANGPT2 mRNA.

PDGFRB upregulation contributes to retinal damages in the rat model of retinal ischemia-reperfusion

Retinal ischemic disease is a major type of retinal diseases causing vision loss. Identifying the molecular mechanisms mediating the retinal ischemia-reperfusion (RIR) is the key to targeted intervention. In this study, we performed RNA-seq analysis of the retinal tissues of a retinal ischemia-reperfusion model of Sprague-Dawley (SD) rats, followed by differential gene expression analysis, gene ontology (GO) enrichment analysis, and protein-protein interaction (PPI) analysis. After studying we found that: The major biological processes affected after RIR was the regulation of vascular development. PPI analysis unveiled a regulatory module in which Platelet Derived Growth Factor Receptor Beta (PDGFRB) was upregulated. In the RIR cell model of human retinal microvascular endothelial cells (HRCEC) induced by oxygen-glucose deprivation/reperfusion (OGD/R), silencing PDGFRB at least partially rescued the detrimental effect on cell proliferation and in vitro angiogenic ability. In the rat model of RIR, the administration of PDGFR inhibitor alleviated the damages in the retinal microvascular system. Besides, we further demonstrated the protective effect of procyanidin against RIR induced damages in both the cell and animal model by dampening the overexpression of PDGFRB. Together, our data indicate that the upregulation of PDGFRB contributes to RIR-induced damages in retinal microvascular system, which provides a targetable strategy for therapeutic intervention.

RNA-Seq Provides Insights into VEGF-Induced Signaling in Human Retinal Microvascular Endothelial Cells: Implications in Retinopathy of Prematurity

The pathophysiology of retinopathy of prematurity (ROP) is postulated to first involve delayed intraretinal vascularization, followed by intravitreal neovascularization (IVNV). Although intravitreal agents that reduce the bioactivity of vascular endothelial growth factor (VEGF) are used to treat IVNV, concerns exist regarding their effects on intraretinal vascularization. In an experimental ROP model, VEGF receptor 2 (VEGFR2) knockdown in retinal endothelial cells reduced IVNV and promoted intraretinal vascularization, whereas knockdown of a downstream effector, signal transducer and activator of transcription 3 (STAT3) in retinal endothelial cells only reduced IVNV. In this study, we tested the hypothesis that the different pathways involved in VEGF-triggered VEGFR2 signaling and VEGF-triggered STAT3 signaling in retinal endothelial cells would allow us to delineate signaling pathways involved in IVNV from those involved in intraretinal vascularization in ROP. To address our hypothesis, we used RNA-sequencing and pathway enrichment analysis to determine changes in the transcriptome of cultured human retinal microvascular endothelial cells (HRMECs). Of the enriched pathways, inactivation of oncostatin M signaling was predicted by either KDR or STAT3 knockdown in the presence of VEGF. Activation of kinetochore metaphase signaling was predicted by KDR knockdown, whereas inactivation was predicted by STAT3 knockdown in the presence of VEGF. Inactivation of signaling by the Rho family of GTPases was predicted by KDR knockdown, but activation was predicted by STAT3 knockdown in the presence of VEGF. Taken together, our data identified unique signaling pathway differences between VEGF-triggered VEGFR2 and VEGF-triggered STAT3 in HRMECs that might have implications in ROP.

High-Fat Diet Alters the Retinal Pigment Epithelium and Choroidal Transcriptome in the Absence of Gut Microbiota

Relationships between retinal disease, diet, and the gut microbiome have started to emerge. In particular, high-fat diets (HFDs) are associated with the prevalence and progression of several retinal diseases, including age-related macular degeneration (AMD) and diabetic retinopathy (DR). These effects are thought to be partly mediated by the gut microbiome, which modulates interactions between diet and host homeostasis. Nevertheless, the effects of HFDs on the retina and adjacent retinal pigment epithelium (RPE) and choroid at the transcriptional level, independent of gut microbiota, are not well-understood. In this study, we performed the high-throughput RNA-sequencing of germ-free (GF) mice to explore the transcriptional changes induced by HFD in the RPE/choroid. After filtering and cleaning the data, 649 differentially expressed genes (DEGs) were identified, with 616 genes transcriptionally upregulated and 33 genes downregulated by HFD compared to a normal diet (ND). Enrichment analysis for gene ontology (GO) using the DEGs was performed to analyze over-represented biological processes in the RPE/choroid of GF-HFD mice relative to GF-ND mice. GO analysis revealed the upregulation of processes related to angiogenesis, immune response, and the inflammatory response. Additionally, molecular functions that were altered involved extracellular matrix (ECM) binding, ECM structural constituents, and heparin binding. This study demonstrates novel data showing that HFDs can alter RPE/choroid tissue transcription in the absence of the gut microbiome.

Network Pharmacology-Based Prediction and Verification of Shikonin for the mechanism treating colorectal cancer

BACKGROUND

Shikonin (SKN), a naturally occurring naphthoquinone, is a major active chemical component isolated from Lithospermum erythrorhizon Sieb Zucc, Arnebia euchroma (Royle) Johnst, or Arnebia guttata Bunge, and commonly used to treat viral infection, inflammation, and cancer. However, the underlying mechanism has not been elucidated.

OBJECTIVE

This study aims to explore the antitumor mechanism of SKN in colorectal cancer (CRC) through network pharmacology and cell experiments.

METHODS

Using SymMap database and Genecards to predict the potential targets of SKN and CRC, while the cotargets were obtained by Venn diagram. The cotargets were imported into website of String and DA DAVID, constructing the protein-protein interaction (PPI) network, performing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, the Compound-Target-Pathway (C-T-P) network was generated by connecting potential pathways with the corresponding targets.

RESULTS

According to the results of network pharmacological analysis, the cell experiments were used to verify the key signal pathway. The most relevant target of SKN for the treatment of CRC was PI3K/Akt signaling pathway. SKN inhibited CRC cells (HT29 and HCT116) proliferation, migration, and invasion, and promoted cell apoptosis by targeting IL6 and inhibiting the IL6R/PI3K/Akt signaling pathway. SKN promotes apoptosis and suppresses CRC cells (HT29 and HCT116) activity through the PI3K-Akt signaling pathway.

CONCLUSION

This research not only provides a theoretical and experimental basis for more in-depth studies but also offers an efficient method for the rational utilization of a series of Traditional Chinese medicines as anti-CRC drugs.