AIM:To identify proangiogenic factors engaged in neovascular age-related macular degeneration(AMD)except vascular endothelial growth factor(VEGF)from human retinal pigment epithelial(h RPE)cells and investigate the underlying mechanisms.METHODS:VEGF receptor 2(VEGFR2)in ARPE-19 cells was depleted by si RNA transfection or overexpressed through adenovirus infection.The m RNA and the protein levels of interleukin-8(IL-8)in ARPE-19 cells were measured by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively.The protein levels of AKT,p-AKT,MEK,p-MEK,ERK1/2,p-ERK1/2,JNK,p-JNK,p38 and p-p38 were detected by Western blotting.A selective chemical inhibitor,LY3214996,was employed to inhibit phosphorylation of ERK1/2.Cell viability was determined by MTT assay.RESULTS:Knockdown of VEGFR2 in ARPE-19 cells robustly augmented IL-8 production at both the m RNA and the protein levels.Silencing VEGFR2 substantially enhanced phosphorylation of MEK and ERK1/2 while exerted no effects on phosphorylation of AKT,JNK and p38.Inhibiting ERK1/2 phosphorylation by LY3214996 reversed changes in VEGFR2 knockdown-induced IL-8 upregulation at the m RNA and the protein levels with no effects on cell viability.VEGFR2 overexpression significantly reduced IL-8 generation at the m RNA and the protein levels.CONCLUSION:Blockade of VEGF signaling augments IL-8 secretion via MEK/ERK1/2 axis and overactivation of VEGF pathway decreases IL-8 production in h RPE cells.Upregulated IL-8 expression after VEGF signaling inhibition in h RPE cells may be responsible for being incompletely responsive to anti-VEGF remedy in neovascular AMD,and IL-8 may serve as an alternative therapeutic target for neovascular AMD.
AIM:To Investigate the genetic findings and phenotypic characteristics of a Chinese family with Norrie disease（ND）.METHODS:Molecular genetic analysis and clinical examinations were performed on a Chinese family with ND.Mutations in the Norrie disease pseudoglioma（NDP）gene were detected by direct sequencing.Haplotypes were constructed and compared with the phenotypes in the family.Evolutionary comparisons and mutant open reading frame（ORF）prediction were also undertaken.RESULTS:Two family members with ocular manifestations were diagnosed with ND.No signs of sensorineural hearing loss were observed in either patient,while one of them showed signs of mild mental retardation.A novel heterozygous mutation in the NDP gene,c.-12delAAT,was detected in both patients.The mutation and the mutation bearing hapiotype cosegregated with the ND phenotype in males and was transmitted from their mothers and/or grandmothers（Ⅱ:2）.The male without ND did not harbor the mutation.The mutation occurred at the highly conserved nucleotides.DRF finder predicted that the mutation would lead to the production of a truncated protein that lacks the first 11N-terminal amino acids.CONCLUSION:A novel mutation,c.-12delAAT in the NDP gene,was identified in a Chinese family with ND.This mutation caused ND without obvious sensorineural hearing loss.Mental disorder was found in one but not the other patients.The clinical heterogeneity in the family indicated that other genetic variants and epigenetic factors may also play a role in the disease presentation.
