Objective: To explore their association with the development of diabetes retinopathy (DR), single nucleotide polymorphism (SNP) mutations were screened out by high-throughput sequencing and validated in patients diagnosed with DR. To understand the role of PIK3CA in the pathogenesis of DR and explore the relationship between PIK3CA,phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR),and DR, the effect of PIK3CA.rs17849079 mutation was investigated in a DR cell model. Methods: Twelve patients diagnosed with DR at the Qinghai Provincial People’s Hospital from September 2020 to June 2021 were randomly selected as the case group, while 12 healthy subjects of similar age and gender who underwent physical examination in Qinghai Provincial People’s Hospital physical examination center during the same period were randomly selected as the control group. Blood samples (2 mL) were collected from both groups using EDTA anticoagulant blood collection vessels and frozen at −20°C for future analysis. SNP mutations were detected by high-throughput sequencing, and the shortlisted candidates were subjected by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The detected SNP candidates were verified by expanding the sample size (first validation: 56 patients in the case group and 58 controls; second validation: 157 patients in the case group and 96 controls). A lentivirus vector carrying mutated or wild-type PIK3CA.rs17849079 was constructed. ARPE-19 cells were cultured in a medium supplemented with 10% fetal bovine serum (FBS) to establish a DR cell model. PIRES2-PIK3CA-MT and PIRES2-PIK3CA-WT vectors were transfected into DR model cells, which were categorized into control, mannitol, model, empty vector, PIK3CA wild-type, and PIK3CA mutant-type groups. Cell activity was detected by the cell counting kit (CCK)-8 assay, and cellular apoptosis was evaluated by flow cytometry. Glucose concentration and levels of cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-1β were detected using enzyme-linked immunosorbent assay kits. The expression of PIK3CA, AKT1, mTOR, and VEGF genes was detected by real-time quantitative polymerase chain reaction (RT-qPCR), while the expression of PI3K, p-PI3K, AKT1, p-AKT1, mTOR, p-mTOR, and VEGF proteins was detected by western blotting. Results: The mutated SNPs were mainly enriched in the PI3K/AKT pathway, calcium ion pathway, and glutamatergic synaptic and cholinergic synaptic signaling pathways. Seven SNPs, including PRKCE.rs1533476, DNAH11.rs10485983, ERAP1.rs149481, KLHL1.rs1318761, APOBEC3C.rs1969643, FYN.rs11963612, and KCTD1.rs7240205, were not related to the development of DR. PIK3CA.rs17849079 was prone to C/T mutation. The risk of DR increased with the presence of the C allele and decreased in the presence of the T allele. High glucose induced the expression of PIK3CA and VEGF mRNAs as well as the expression of PI3K, p-PI3K, p-AKT1, p-mTOR, and VEGF proteins in ARPE-19 cells, which led to secretion of inflammatory factors TNF-αand IL-1, cell apoptosis, and inhibition of cell proliferation. The PIK3CA.rs17849079 C allele accelerated the progression of DR. These biological effects were inhibited when the C allele of PIK3CA.rs17849079 was mutated to T allele. Conclusion: The mutated SNP sites in patients with DR were mainly enriched in PI3K/AKT, calcium ion, and glutamatergic synaptic and cholinergic synaptic signaling pathways. The rs17849079 allele of PIK3CA is prone to C/T mutation where the C allele increases the risk of DR. High glucose activates the expression of PIK3CA and promotes the phosphorylation of PI3K, which leads to the phosphorylation of AKT and mTOR. These effects consequently increase VEGF expression and accelerate the development of DR. The C to T allele mutation in PIK3CA.rs17849079 can play a protective role and reduce the risk of DR.

Purpose: Glaucoma is a generic term of a highly different disease group of optic neuropathies, which the leading cause of irreversible vision in the world. There are few biomarkers available for clinical prediction and diagnosis, and the diagnosis of patients is mostly delayed. Methods: Differential gene expression of transcriptome sequencing data (GSE9944 and GSE2378) for normal samples and glaucoma samples from the GEO database were analyzed. Furthermore, based on different algorithms (Logistic Regression (LR), Random Forest (RF), lasso regression (LASSO)) two diagnostic models are constructed and diagnostic markers are screened. GO and KEGG analyses revealed the possible mechanism of differential genes in the pathogenesis of glaucoma. ROC curve confirmed the effectiveness. Results: LR-RF model included 3 key genes (NAMPT, ADH1C, ENO2), and the LASSO model outputted 5 genes (IFI16, RFTN1, NAMPT, ADH1C, and ENO2), both algorithms have excellent diagnostic efficiency. ROC curve confirmed that the three biomarkers ADH1C, ENO2, and NAMPT were effective in the diagnosis of glaucoma. Next, the expression analysis of the three diagnostic biomarkers in glaucoma and control samples confirmed that NAMPT and ADH1C were up-regulated in glaucoma samples, and ENO2 was down-regulated. Correlation analysis showed that ENO2 was significantly negatively correlated with ADH1C (cor = -0.865714202) and NAMPT (cor = -0.730541227). Finally, three compounds for the treatment of glaucoma were obtained in the TCMs database: acetylsalicylic acid, 7-o-methylisomucitol and scutellarin which were applied to molecular docking with the diagnostic biomarker ENO2. Conclusions: In conclusion, our research shows that ENO2, NAMPT, and ADH1C can be used as diagnostic markers for glaucoma, and ENO2 can be used as a therapeutic target.