In depth understanding of retinitis pigmentosa pathogenesis through optical coherence tomography angiography analysis: a narrative review.

Retinitis pigmentosa (RP) is the most recognized inherited retinal disorder involving progressive photoreceptors degeneration which eventually causes blindness. However, the pathogenesis of RP is still unclear, making it difficult to establish satisfying treatments. Evidence have been found to support the theory that vascular dysfunction is associated with the progression of RP. Optical coherence tomography angiography (OCTA) is a newly developed technology that enables visualization as well as quantitative assessment of retinal and choroidal vasculature non-invasively. Advances in OCTA have opened a window for in-depth understanding of RP pathogenesis. Here, we propose a hypothesis of RP pathogenesis based on the current OCTA findings in RP, which includes four stages and two important key factors, vascular dysfunction and microglia activation. Further, we discuss the future animal experiments needed and how advanced OCTA technology can help to further verity the hypothesis. The final goal is to explore potential treatment options with enhanced understanding of RP pathogenesis.

Traditional Chinese medicine Xiaosheng Powder for dry eye disease: A protocol for systematic review and meta analysis.

BACKGROUND: Dry eye disease (DED) has shown a significant increase in recent years, which seriously affects people's work and life. Xiaosheng Powder, a traditional Chinese medicine decoction, has been widely used in treating DED. However, there is no systematic review of the results of the study on this therapeutic effect. The purpose of this review is to evaluate the effectiveness and safety of Xiaosheng Powder in the treatment of DED. METHODS AND ANALYSIS: The electronic databases to be searched will include MEDLINE (PubMed), Cochrane Central Register of Controlled Trials in the Cochrane Library, Excerpta Medica Database, China National Knowledge Infrastructure, China Scientific Journal Database, Wanfang Database and Chinese Biomedical Literature Database. Papers in English or Chinese published from inception to 2020 will be included without any restrictions. Improvement in Ocular Surface Disease Index will be assessed as the primary outcomes. Tear break-up time, Schirmer I test, fluorescent, adverse events, and the recurrence rate after at least 3 months of the treatment will be evaluated as secondary outcomes. We will conduct a meta-analysis of randomized controlled trial if possible. The methodological qualities, including the risk of bias, will be evaluated using the Cochrane risk of bias assessment tool, while confidence in the cumulative evidence will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation approach. ETHICS AND DISSEMINATION: It is not necessary for a formal ethical approval because the data is not individualized. The results of this review will offer implications for the use of Xiaosheng Powder as a treatment for DED. This knowledge will inform recommendations by ophthalmologist and researchers who are interested in the treatment of DED. The findings of this systematic review will be disseminated through peer-reviewed publications and conference presentations. TRAIL REGISTRATION NUMBER: PROSPERO CRD42020147709.

A Network Pharmacology to Explore the Mechanism of Astragalus Membranaceus in the Treatment of Diabetic Retinopathy.

BACKGROUND: Diabetic retinopathy (DR) includes a series of typical lesions affected by retinal microvascular damage caused by diabetes mellitus (DM), which not only seriously damages the vision, affecting the life's quality of patients, but also brings a considerable burden to the family and society. Astragalus Membranaceus (AM) is a commonly used medicine in clinical therapy of eye disorders in traditional Chinese medicine (TCM). In recent years, it is also used for treating DR, but the specific mechanism is unclear. Therefore, this study explores the potential mechanism of AM in DR treatment by using network pharmacology. METHODS: Based on the oral bioavailability (OB) and drug likeness (DL) of two ADME (absorption, distribution, metabolism, excretion) parameters, Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Swiss Target Prediction platform, GeneCards, and OMIM database were used to predict and screen the active compounds of AM, the core targets of AM in DR treatment. The Metascape data platform was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis on the core targets. RESULTS: 24 active compounds were obtained, such as quercetin, kaempferol, and astragaloside IV. There were 169 effective targets of AM in DR treatment, and the targets were further screened and finally, 38 core targets were obtained, such as VEGFA, AKT1, and IL-6. EGFR tyrosine kinase inhibitor resistance, AGE-RAGE signaling pathway in diabetic complications, PI3K-Akt signaling pathway, and other metabolic pathways participated in oxidative stress, cell apoptosis, angiogenesis signal transduction, inflammation, and other biological processes. CONCLUSION: AM treats DR through multiple compounds, multiple targets, and multiple pathways. AM may play a role in the treatment of DR by targeting VEGFA, AKT1, and IL-6 and participating in oxidative stress, angiogenesis, and inflammation.