Evidence map›Paper›PMID 36035211›Full record

ArticleOxidative medicine and cellular longevity2022

Pigment Epithelium-Derived Factor Protects Retinal Neural Cells and Prevents Pathological Angiogenesis in an

Lei Xi, Marina Tikhonovich, Antje Biesemeier, Sylvie Julien-Schraermeyer, Ulrich Schraermeyer, Alexander V Tschulakow

Abstract read
In one paragraph

Article in Oxidative medicine and cellular longevity, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed.

  1. Pigment Epithelium-Derived Factor (PEDF)-Based Therapy Induced Photoreceptor Survival by Stabilizing Choroidal Neovessels in a VEGF Overexpression CNV Rat Model.FASEB journal : official publication of the Federation of American Societies for Experimental Biology · 2025
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Lei XiDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.ORCID https://orcid.org/0000-0003-3746-3132
Marina TikhonovichDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.
Antje BiesemeierDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.ORCID https://orcid.org/0000-0002-3462-8803
Sylvie Julien-SchraermeyerDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.ORCID https://orcid.org/0000-0002-2322-511X
Ulrich SchraermeyerDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.ORCID https://orcid.org/0000-0002-7969-8426
Alexander V TschulakowDivision of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tuebingen, Tuebingen, Germany.ORCID https://orcid.org/0000-0001-5112-8838

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Ocular ischemia/hypoxia is a severe problem in ophthalmology that can cause vision impairment and blindness. However, little is known about the changes occurring in the existing fully formed choroidal blood vessels. We developed a new whole organ culture model for ischemia/hypoxia in rat eyes and investigate the effects of pigment epithelium derived factor (PEDF) protein on the eye tissues. The concentration of oxygen within the vitreous was measured in the enucleated rat eyes and living rats. Then, ischemia was mimicked by incubating the freshly enucleated eyes in medium at 4°C for 14 h. Eyes were fixed immediately after enucleation or were intravitreally injected with PEDF protein or with vehicle before incubation. After incubation, light and electron microscopy (EM) as well as Tunel staining was performed. In the living rats, the intravitreal oxygen concentration was on average at 16.4% of the oxygen concentration in the air and did not change throughout the experiment whereas it was ca. 28% at the beginning of the experiment and gradually decreased over time in the enucleated eyes. EM analysis revealed that the shape of the choriocapillaris changed dramatically after 14 h incubation in the enucleated eyes. The endothelial cells made filopodia-like projections into the vessel lumen. They appeared identical to the labyrinth capillaries found in surgically extracted choroidal neovascular membranes from patients with wet age-related macular degeneration (AMD). These filopodia-like projections nearly closed the vessel lumen and showed open gaps between neighboring endothelial cells. PEDF significantly inhibited labyrinth capillary formation and kept the capillary lumen open. The number of TUNEL-positive ganglion cells and inner nuclear layer cells was significantly reduced in the PEDF-treated eyes compared to the vehicle-treated eyes. The structural changes in the chroidal vessels observed under ischemia/hypoxia conditions can mimic early changes in the process of pathological angiogenesis as observed in wet AMD patients. This new model can be used to investigate short-term drug effects on the choriocapillaris after ischemia/hypoxia and it highlighted the potential of PEDF as a promising candidate for treating wet AMD.

Indexed as

Choroidal NeovascularizationSerpinsAnimalsEndothelial CellsEye ProteinsHypoxiaIschemiaNeovascularization, PathologicNerve Growth FactorsOxygenPigment Epithelium-Derived FactorRatsEye ProteinsNerve Growth FactorsOxygenPigment Epithelium-Derived FactorSerpins

Identifiers

PMID36035211
PMCPMC9410835

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.