ERI scientists are hard at work learning about vision

Members of the OU’s renowned Eye Research Institute are hard at work uncovering new knowledge about vision.

Associate Professor and CBR member Shravan Chintala published a report titled “Curcumin Attenuates Staurosporine-Mediated Death of Retinal Ganglion Cells” in the June issue of Investigative Ophthalmology & Visual Science (Volume 52, Pages 4263-4273). Coauthors include Balabharathi Burugula and Bhagyalaxmi Ganesh, both of whom work in Chintala’s laboratory, which is funded by a grant from the National Institutes of Health. Their abstract states

“Staurosporine causes retinal ganglion cell death in vivo, but the underlying mechanisms have been unclear. Since previous studies on retinal ganglion cell-5 cells indicated that staurosporine induces cell death by elevating proteases, this study was undertaken to investigate whether stayrosporine induces retinal ganglion loss by elevating proteases in the retina, and [whether] curcumin prevents staurosporine-mediated death of retinal ganglion cells…. The results show that curcumin attenuates retinal ganglion cell and amacrine cell death despite elevated levels of proteases and raises the possibility that it may be used as a plausible adjuvant therapeutic agent to prevent the loss of these cells in retinal degenerative conditions.”

Eye Research Institute director and CBR member Frank Giblin reports in the journal Investigative Ophthamology & Visual Science (Volume 52, Pages 3667-3675) that “A Class I (Senofilcon A) Soft Contact Lens Prevents UVB-Induced Ocular Effects, Including Cataract, in the Rabbit In Vivo.” His coauthors are Li-Ren Lin, Victor Leverenz,a and Loan Dang, and his research is supported by an National Institutes of Health grant. From the abstract:

“Ultraviolet-B radiation from sunlight is known to be a risk factor for human cataract. The purpose in this study was to investigate the ability of a class I UV-blocking soft contact lens to protect against UVB-induced effects on the ocular tissues of the rabbit in vivo…. The results indicate that use of a senofilcon A contact lens is beneficial in protecting ocular tissues of the rabbit against the harmful effects of UVB light, including photokeratitis and cataract.”

Associate Professor and CBR Member Ken Mitton has the paper “The Transcription Factor NRL1 Controls Photoreceptor-Specific Expression of Myocyte Enhancer Factor Mef2c From an Alternative Promoter” in press at the Journal of Biological Chemistry. His OU coauthors include Tummala Padmaja, Eduardo Guzman and Raghuveer Mali. Mitton’s study was supported by a grant from the National Institutes of Health. The abstract states

“NRL (Neural Retina Leucine zipper) is an essential transcription factor for cell fate specification and functional maintenance of rod photoreceptors in the mammalian retina. In the Nrl-/- mouse retina, photoreceptor precursors fail to produce rods and generate functional cone photoreceptors that predominantly express S-opsin. Previous global expression analysis using microarrays revealed dramatically reduced expression of myocyte enhancer factor Mef2c in the adult Nrl-/- retina. We undertook this study to examine the biological relevance of Mef2c expression in retinal rod photoreceptors. Bioinformatics analysis, rapid analysis of cDNA ends (5′-RACE), and reverse transcription coupled with qPCR using splice-site specific oligonucleotides suggested that Mef2c is expressed in the mature retina from an alternative promoter. Chromatin immunoprecipitation (ChIP) studies showed the association of active RNA polymerase-II and acetylated histone H3 just upstream of Mef2c exon 4, providing additional evidence for the utilization of an alternative promoter in the retina. In concordance, we observed the binding of NRL to a putative NRL-response element (NRE) at this location by ChIP-seq and electrophoretic mobility shift assays. NRL also activated the Mef2c alternative promoter in vitro and in vivo. Notably, MEF2C could support Rhodopsin promoter activity in rod photoreceptors. We conclude that Mef2c expression from an alternative promoter in the retina is regulated by NRL. Our studies also implicate MEF2C as a transcriptional regulator of homeostasis in rod photoreceptor cells. ”