@article{LittsAchHammacketal.2016, author = {Litts, Katie M. and Ach, Thomas and Hammack, Kristen M. and Sloan, Kenneth R. and Zhang, Yuhua and Freund, K. Bailey and Curcio, Christine A.}, title = {Quantitative Analysis of Outer Retinal Tubulation in Age-Related Macular Degeneration From Spectral-Domain Optical Coherence Tomography and Histology}, series = {Investigative Ophthalmology \& Visual Science}, volume = {57}, journal = {Investigative Ophthalmology \& Visual Science}, doi = {10.1167/iovs.16-19262}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165532}, pages = {2647-2656}, year = {2016}, abstract = {Purpose: To assess outer retinal tubulation (ORT) morphology from spectral-domain optical coherence tomography (SD-OCT) volumes and donor eye histology, analyze ORT reflectivity, and estimate the number of cones surviving in ORT. Methods: In SD-OCT volumes from nine patients with advanced AMD, ORT was analyzed en face and in B-scans. The hyperreflective ORT border in cross-section was delineated and surface area calculated. Reflectivity was compared between ORT types (Closed, Open, Forming, and Branching). A flatmount retina from a donor with neovascular AMD was labeled to visualize the external limiting membrane that delimits ORT and allow measurements of cross-sectional cone area, center-to-center cone spacing, and cone density. The number of cones surviving in ORT was estimated. Results: By en face SD-OCT, ORT varies in complexity and shape. Outer retinal tubulation networks almost always contain Closed cross-sections. Spectral-domain OCT volumes containing almost exclusively Closed ORTs showed no significant direction-dependent differences in hyperreflective ORT border intensity. The surface areas of partial ORT assessed by SD-OCT volumes ranged from 0.16 to 1.76 mm2. From the flatmount retina, the average cross-sectional area of cone inner segments was 49.1 ± 7.9 μm2. The average cone spacing was 7.5 ± 0.6 μm. Outer retinal tubulation cone density was 20,351 cones/mm2. The estimated number of cones in ORT in a macula ranged from 26,399 to 186,833 cones, which is 6\% to 44\% of the cones present in a healthy macula. Conclusions: These first estimates for cone density and number of cones surviving in ORT suggest that ORT formation considerably distorts the photoreceptor mosaic. Results provide additional insight into the reflectivity characteristics and number of ORT cones observable in living patients by SD-OCT, as cones persist and disease progresses.}, language = {en} } @article{RichertKoinzerTodeetal.2018, author = {Richert, Elisabeth and Koinzer, Stefan and Tode, Jan and Schlott, Kerstin and Brinkmann, Ralf and Hillenkamp, Jost and Klettner, Alexa and Roider, Johann}, title = {Release of Different Cell Mediators During Retinal Pigment Epithelium Regeneration Following Selective Retina Therapy}, series = {Investigative Ophthalmology \& Visual Science}, volume = {59}, journal = {Investigative Ophthalmology \& Visual Science}, number = {3}, doi = {10.1167/iovs.17-23163}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226161}, pages = {1323-1331}, year = {2018}, abstract = {PURPOSE. To investigate the effect of selective retina therapy (SRT) on the release of AMD-relevant cell mediators, such as matrix metalloproteinases (MMPs), VEGF, and pigment epithelium derived factor (PEDF) using different laser spot sizes and densities. METHODS. Porcine RPE-choroid explants were treated with a pulsed 532 nm Nd:YAG laser using (1) large spot sizes, (2) small spot sizes with a high-density (hd) treatment, and (3) small spot sizes with a low-density (1d) treatment. Explains were cultivated in modified Ussing chambers. RPE regeneration and RPE cell death were investigated by calcein-AM staining and immunofluorescence. The MMP release was examined via zymography and immunofluorescence. VEGF and PEDF secretion was analyzed by ELISA. RESULTS. During pigment epithelium regeneration (PER), mitosis and RPE cell migration were observed. Four days after SRT (large spot size) the content of active MMP2 increased significantly (P < 0.01). Hd treatment with small spot sizes resulted also in an increase of active MMP2 (P < 0.05). In immunofluorescence explants showed a localized expression of MMP2 within the healing lesions after irradiation. The PEDF level increased significantly (P = 0.01) after SRT with large spot sizes. VEGF secretion decreased significantly (P < 0.05) following SRT with large spot sizes and with hd treatment of small spot sizes. CONCLUSIONS. SRT induces a cytokine profile, which may improve the flux across Brach's membrane, slows down progression of early AMD by RPE regeneration, and inhibits the formation of choroidal neovascularization. The cytokine release depends on the size and density of applied laser spots.}, language = {en} } @article{SchlechtVallonWagneretal.2021, author = {Schlecht, Anja and Vallon, Mario and Wagner, Nicole and Erg{\"u}n, S{\"u}leyman and Braunger, Barbara M.}, title = {TGFβ-Neurotrophin Interactions in Heart, Retina, and Brain}, series = {Biomolecules}, volume = {11}, journal = {Biomolecules}, number = {9}, issn = {2218-273X}, doi = {10.3390/biom11091360}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246159}, year = {2021}, abstract = {Ischemic insults to the heart and brain, i.e., myocardial and cerebral infarction, respectively, are amongst the leading causes of death worldwide. While there are therapeutic options to allow reperfusion of ischemic myocardial and brain tissue by reopening obstructed vessels, mitigating primary tissue damage, post-infarction inflammation and tissue remodeling can lead to secondary tissue damage. Similarly, ischemia in retinal tissue is the driving force in the progression of neovascular eye diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD), which eventually lead to functional blindness, if left untreated. Intriguingly, the easily observable retinal blood vessels can be used as a window to the heart and brain to allow judgement of microvascular damages in diseases such as diabetes or hypertension. The complex neuronal and endocrine interactions between heart, retina and brain have also been appreciated in myocardial infarction, ischemic stroke, and retinal diseases. To describe the intimate relationship between the individual tissues, we use the terms heart-brain and brain-retina axis in this review and focus on the role of transforming growth factor β (TGFβ) and neurotrophins in regulation of these axes under physiologic and pathologic conditions. Moreover, we particularly discuss their roles in inflammation and repair following ischemic/neovascular insults. As there is evidence that TGFβ signaling has the potential to regulate expression of neurotrophins, it is tempting to speculate, and is discussed here, that cross-talk between TGFβ and neurotrophin signaling protects cells from harmful and/or damaging events in the heart, retina, and brain.}, language = {en} } @article{TarauBerlinCurcioetal.2019, author = {Tarau, Ioana-Sandra and Berlin, Andreas and Curcio, Christine A. and Ach, Thomas}, title = {The cytoskeleton of the retinal pigment epithelium: from normal aging to age-related macular degeneration}, series = {International Journal of Molecular Science}, volume = {20}, journal = {International Journal of Molecular Science}, number = {14}, issn = {1422-0067}, doi = {10.3390/ijms20143578}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201781}, year = {2019}, abstract = {The retinal pigment epithelium (RPE) is a unique epithelium, with major roles which are essential in the visual cycle and homeostasis of the outer retina. The RPE is a monolayer of polygonal and pigmented cells strategically placed between the neuroretina and Bruch membrane, adjacent to the fenestrated capillaries of the choriocapillaris. It shows strong apical (towards photoreceptors) to basal/basolateral (towards Bruch membrane) polarization. Multiple functions are bound to a complex structure of highly organized and polarized intracellular components: the cytoskeleton. A strong connection between the intracellular cytoskeleton and extracellular matrix is indispensable to maintaining the function of the RPE and thus, the photoreceptors. Impairments of these intracellular structures and the regular architecture they maintain often result in a disrupted cytoskeleton, which can be found in many retinal diseases, including age-related macular degeneration (AMD). This review article will give an overview of current knowledge on the molecules and proteins involved in cytoskeleton formation in cells, including RPE and how the cytoskeleton is affected under stress conditions — especially in AMD.}, language = {en} }