Blog
About

11
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Retinal ganglion cell-conditioned medium and surrounding pressure alters gene expression and differentiation of rat retinal progenitor cells

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Loss of retinal ganglion cells is implicated in glaucoma and high intraocular pressure. Factors that affect the differentiation of retinal progenitor cells into retinal ganglion cells remain unclear. The present study aimed to investigate the effects of retinal ganglion cell-conditioned medium on gene expression and differentiation in retinal progenitor cells, and the effects of surrounding pressure on the survival and differentiation of retinal progenitor cells. Retinal progenitor cells and retinal ganglion cells were isolated from rats. Immunofluorescence staining of Nestin and Thy1 was performed to identify rat retinal progenitor cells and retinal ganglion cells, respectively. Retinal progenitor cells and ganglion cells were cultured for 48 h under surrounding pressure of 0, 20, 40, 60 and 80 mmHg. Cellular apoptosis was detected using a caspase-3 assay kit. In addition, the culture supernatant of rat retinal ganglion cells was collected. Retinal progenitor cells were cultured in the presence or absence of retinal ganglion-conditioned medium for 72 h under normal pressure. Gene expression of Nestin, paired box protein 6 (PAX6), Thy1 and brain-specific homeobox/POU domain protein 3 (Brn-3) in retinal progenitor cells was detected by reverse transcription-quantitative polymerase chain reaction. Retinal progenitor cells were cultured in retinal ganglion-conditioned medium for 72 h under surrounding pressure of 0 and 40 mmHg, respectively, and flow cytometry was utilized to evaluate the effects of pressure on the differentiation of retinal progenitor cells into retinal ganglion cells. The results demonstrated that isolated retinal progenitor cells were Nestin-positive and retinal ganglion cells were Thy1-positive, suggesting successful isolation. The activity of caspase-3 increased in retinal progenitor cells and retinal ganglion cells in a pressure-dependent manner. When the surrounding pressure reached 40, 60 and 80 mmHg, the activity of caspase-3 in retinal progenitor cells and ganglion cells increased significantly compared with cells that were not under pressure. Compared with retinal progenitor cells cultured without ganglion-conditioned medium, those cultured with ganglion-conditioned medium had significantly decreased expression levels of Nestin and PAX6, and increased expression levels of Thy1 and Brn3. Compared with 0 mmHg pressure, retinal progenitor cells cultured in ganglion-conditioned medium under 40 mmHg pressure had increased percentages of Thy1-positive cells. In conclusion, the apoptosis of rat retinal progenitor cells and retinal ganglion cells was pressure-dependent. Retinal ganglion cell-conditioned medium increased the differentiation of retinal progenitor cells into retinal ganglion-like cells, and the differentiation increased as surrounding pressure increased. Current study provides insights that may contribute to the efforts of developing a treatment for glaucoma.

          Related collections

          Most cited references 33

          • Record: found
          • Abstract: found
          • Article: not found

          Relationship between intraocular pressure and primary open angle glaucoma among white and black Americans. The Baltimore Eye Survey.

          A detailed ocular examination, including perimetry, was conducted on 5308 black and white subjects aged 40 years and older in a population-based prevalence survey in east Baltimore, Md. Repeated, detailed examinations were carried out on selected subjects. Roughly half of all subjects with optic nerve damage from primary open angle glaucoma, regardless of race, were unaware that they had the condition. The average intraocular pressure (IOP) among black patients with glaucoma who were receiving treatment was virtually identical to that in those black patients who were not receiving treatment (median IOP, 20 mm Hg); treated eyes of white patients had a lower IOP than those eyes of white patients who were not receiving treatment (mean [+/- SD] IOP, 18.69 +/- 3.23 mm Hg vs 24.15 +/- 5.23 mm Hg; P less than .001). The risk of glaucomatous optic nerve damage increased with the height of the screening IOP, particularly at levels of 22 to 29 and 30 mm Hg and above (relative rate compared with IOP of 15 mm Hg or lower, 12.8 and 40.1 mm Hg, respectively). More than half of all glaucomatous eyes had a screening IOP below 21 mm Hg, whether these eyes were receiving treatment or not. The IOP in glaucomatous eyes tended to rise on follow-up, in contrast with nonglaucomatous eyes in which the IOP was as likely to rise as to fall. Results confirmed that IOP is an important factor in glaucoma, but did not support the traditional distinction between "normal" and "elevated" pressure, nor its corollaries, "low-tension" glaucoma and "high-tension" glaucoma.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            The potential role of glutamate transporters in the pathogenesis of normal tension glaucoma.

            Glaucoma, a progressive optic neuropathy due to retinal ganglion cell (RGC) degeneration, is one of the leading causes of irreversible blindness. Although glaucoma is often associated with elevated intraocular pressure (IOP), IOP elevation is not detected in a significant subset of glaucomas, such as normal tension glaucoma (NTG). Moreover, in some glaucoma patients, significant IOP reduction does not prevent progression of the disease. Thus, understanding IOP-independent mechanisms of RGC loss is important. Here, we show that mice deficient in the glutamate transporters GLAST or EAAC1 demonstrate spontaneous RGC and optic nerve degeneration without elevated IOP. In GLAST-deficient mice, the glutathione level in Müller glia was decreased; administration of glutamate receptor blocker prevented RGC loss. In EAAC1-deficient mice, RGCs were more vulnerable to oxidative stress. These findings suggest that glutamate transporters are necessary both to prevent excitotoxic retinal damage and to synthesize glutathione, a major cellular antioxidant and tripeptide of glutamate, cysteine, and glycine. We believe these mice are the first animal models of NTG that offer a powerful system for investigating mechanisms of neurodegeneration in NTG and developing therapies directed at IOP-independent mechanisms of RGC loss.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              The pig eye as a novel model of glaucoma.

              We validated the pig eye as a model of glaucoma, based on chronic elevation of intraocular pressure (IOP). IOP was elevated by cauterising three episcleral veins in each of the left eyes of five adult pigs. Right eyes were used as controls. Measurement of IOP was performed during the experiment with an applanation tonometer (Tono-Pen). Five months after episcleral vein occlusion, retinal ganglion cells (RGCs) from both cauterised and control eyes were retrogradely backfilled with Fluoro-Gold. Analysis of RGC loss and morphometric as characterization of surviving RGCs was performed using whole-mounted retinas. Elevation of IOP was apparent after three weeks of episcleral vein cauterisation and it remained elevated for at least 21 weeks (duration of the experiments). Analysis of RGC loss after chronic elevation of IOP revealed that RGC death was significant in the mid-peripheral and peripheral retina, mainly in the temporal quadrants of both retinal regions. Moreover the mean soma area of remaining RGCs was observed to increase and we found a greater loss of large RGCs in the mid-peripheral and peripheral retina. We conclude that the pattern of RGC death induced in the pig retina by episcleral vein cauterisation resembles that found in human glaucoma. On the basis of this study, the pig retina may be considered as a suitable model for glaucoma-related studies, based on its similarity with human and on its affordability.
                Bookmark

                Author and article information

                Journal
                Mol Med Rep
                Mol Med Rep
                Molecular Medicine Reports
                D.A. Spandidos
                1791-2997
                1791-3004
                May 2018
                14 March 2018
                14 March 2018
                : 17
                : 5
                : 7177-7183
                Affiliations
                [1 ]Department of Ophthalmology, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
                [2 ]Key Laboratory of Yunnan Province for The Prevention and Treatment of Ophthalmology, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
                [3 ]Provincial Innovation Team for Cataract and Ocular Fundus Disease, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
                [4 ]Yunnan Eye Institute, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
                [5 ]Expert Workstation of Yao Ke, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
                [6 ]Department of Ophthalmology, Yan'an Hospital, Kunming, Yunan 650051, P.R. China
                Author notes
                Correspondence to: Dr Jianzhou Wang, Department of Ophthalmology, Yan'an Hospital, 245 Renmin East Road, Panlong, Kunming, Yunan 650051, P.R. China, E-mail: yayywjz@ 123456163.com
                Article
                mmr-17-05-7177
                10.3892/mmr.2018.8738
                5928676
                29568879
                Copyright: © Dai et al.

                This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

                Categories
                Articles

                Comments

                Comment on this article