DNA Methylation Analysis of Human Trabecular Meshwork Cells During Dexamethasone Stimulation.

PURPOSE: We investigated the changes in the DNA methylation status of cultured human trabecular meshwork (TM) cells during glucocorticoid exposure, and evaluated the effect of epigenetic modification on the gene expression of TM cells. METHODS: Three batches of primary culture TM cells were treated with and without 100 nM dexamethasone (DEX) for 14 days. Genome-wide methylation analysis was done using Illumina 450 K methylation chips. The gene expression profile of the TM cells also was examined. The epigenetic effect of DEX stimulation on gene expression in TM cells was further verified by treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) and subsequent real-time PCR analysis. RESULTS: After DEX stimulation, we found demethylated cytosine-phosphate-guanine (CpG) sites within the FKBP5, ZBTB16, and SCNN1A gene promoter regions with increases of corresponding gene expression for all three TM batches, and methylated CpG sites within the ARSI, HIC1, GREM2, and MATN2 gene promoter regions with decreases of corresponding of gene expression for all three batches. Inhibition of DNA methylation by 5-aza-dC treatment induced a further increase of FKBP5 and SCNN1A mRNA expression under DEX stimulation. CONCLUSIONS: The DEX stimulation induces alteration of the DNA methylation status in human TM cells. Epigenetic modification could affect the TM gene expression profile.

Atopic Glaucoma: Clinical and Pathophysiological Analysis.

PURPOSE: Open-angle glaucoma associated with severe atopic dermatitis (atopic glaucoma) tends to be severe and difficult to treat because of ocular surface/eye lid inflammation. To determine the validity of regarding atopic glaucoma as a clinical entity, we carried out retrospective analysis and pathologic investigations. MATERIALS AND METHODS: Forty-five cases (62 eyes) of atopic glaucoma were reviewed retrospectively. During surgical treatment, aqueous humor and trabeculectomy specimens were obtained. The aqueous humor samples were analyzed by multiplex cytokine assay. The surgical specimens were analyzed histologically. RESULTS: Atopic glaucoma was often associated with atopic cataracts (43 eyes) and retinal detachments (19 eyes). A history of glucocorticoid medications was absent in 12 cases. A total of 50 eyes required surgical interventions because of advanced visual field defects and/or high intraocular pressures. Bleb-associated postsurgical infections were observed in 7 eyes. Elevated levels of inflammatory cytokines (IL-8 and CCL2) were observed in the aqueous humor samples obtained from atopic glaucoma patients compared with those from senile cataract patients. Ultrastructural analysis of trabecular meshwork tissues obtained from atopic glaucoma patients showed abnormal accumulation of 10 to 30 nm fibers in the corneoscleral meshwork. CONCLUSIONS: We would like to propose atopic glaucoma as a new clinical entity, ranging from pure atopic glaucoma to a mixed type of atopic/steroid-induced glaucoma that should be considered as one of the clinical features of atopic ocular complications.