Abstract
Purpose :
Abnormal neovascularization of the retina is a fundamental cause of blindness in a number of eye diseases. Müller cells are an important source of vascularization signals in the retina. We have shown in previously that retinal circadian clock genes including Period1 and 2, Bmal1 are expressed in retinal Müller cells and may be critical modulators of retinal vascularizing responses. And, we have shown that decreased expression of the Hif1-a signaling pathway and increased expression of VEGFa by RNAseq analyses in C3Hf+/+ mouse Müller cells treated with hypoxia. Here we compared the RNAseq analyses C57, Per gene ko and Bmal1 ko mouse retinal Müller cells treated in normoxia and hypoxia to identify the genes and pathways potentially involved in retinal neovascularization.
Methods :
Purified primary wild type, Per1-/-/Per2-/- and Bmal1-/- mouse retinal Müller cells were cultured in DMEM containing 10% FBS at 37°C in a 5% CO2 incubator. The three types of Müller cells were serum starved for 12 hours and then were grown at 37°C for 24 hours in growth medium under both normoxic and hypoxic (O2 < 5%) conditions. Gene expression was measured by RNAseq and validated by RT-PCR. Genes with a false-discovery rate of ≤ 0.05 were considered significantly different. Ingenuity was used to identify cellular functions and biological pathways.
Results :
There were thousands of gene expression changes in the three types of mouse Müller cells treated with hypoxia. Decreased expression of Hif1-a in C57 and increased expression of VEGFa and Rora occurred in all three cell types. Per1, Bmal1, MT1 and MT2 were increased in all of three cell types. Decreased expression of Hif1-a occurred in Per-/-/Per2-/- and Bmal1-/- Müller cells compared to wt C57 in normoxia.
Conclusions :
Our results suggest that genes and pathways known to be involved in angiogenesis, as well as other biologically plausible genes and pathways, are regulated directly by hypoxic conditions in mouse Müller cells.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.