Search results for "EYE"

2017

Purpose Hydrogen sulfide (H2S) is recognized as a novel third signaling molecule and gaseous neurotransmitter. Recently, cell protective properties within the central nervous and cardiovascular system have been proposed. Our purpose was to analyze the expression and neuroprotective effects of H2S in experimental models of glaucoma. Methods Elevated IOP was induced in Sprague-Dawley rats by means of episcleral vein cauterization. After 7 weeks, animals were killed and the retina was analyzed with label-free mass spectrometry. In vitro, retinal explants were exposed to elevated hydrostatic pressure or oxidative stress (H2O2), with and without addition of a slow-releasing H2S donor Morpholin-4…

2016

AbstractGlaucoma related proteomic changes have been documented in cell and animal models. However, proteomic studies investigating on human retina samples are still rare. In the present work, retina samples of glaucoma and non-glaucoma control donors have been examined by a state-of-the-art mass spectrometry (MS) workflow to uncover glaucoma related proteomic changes. More than 600 proteins could be identified with high confidence (FDR < 1%) in human retina samples. Distinct proteomic changes have been observed in 10% of proteins encircling mitochondrial and nucleus species. Numerous proteins showed a significant glaucoma related level change (p < 0.05) or distinct tendency of altera…

N-retinylidene-N-retinylethanolamine adduct induces expression of chronic inflammation cytokines in retinal pigment epithelium cells

2021

Blindness due to photoreceptor degeneration is observed in both genetic and acquired eye disorders. Long blue light exposure can contribute to increase levels of oxidative compounds within the retinal pigment epithelium (RPE), enhancing risk of retinal damage. In retina, reactive oxygen species contribute to the activation of inflammatory cascade. If chronic, this inflammatory response can result in photoreceptor death. Therefore, we investigated the effects of the endogenous adduct N-retinylidene-N-retinylethanolamine (A2E) on RPE cells, in order to identify the most dysregulated cytokines and their related inflammatory pathways. RPE cells were exposed to A2E and blue light for 3h and 6h. …

Primary Cilium-Mediated Retinal Pigment Epithelium Maturation Is Disrupted in Ciliopathy Patient Cells

2018

SUMMARY Primary cilia are sensory organelles that protrude from the cell membrane. Defects in the primary cilium cause ciliopathy disorders, with retinal degeneration as a prominent phenotype. Here, we demonstrate that the retinal pigment epithelium (RPE), essential for photoreceptor development and function, requires a functional primary cilium for complete maturation and that RPE maturation defects in ciliopathies precede photoreceptor degeneration. Pharmacologically enhanced ciliogenesis in wild-type induced pluripotent stem cells (iPSC)-RPE leads to fully mature and functional cells. In contrast, ciliopathy patient-derived iPSC-RPE and iPSC-RPE with a knockdown of ciliary-trafficking pr…

Generation of an inducible RPE-specific Cre transgenic-mouse line.

2018

The retinal pigment epithelium (RPE) is an epithelial monolayer in the back of the vertebrate eye. RPE dysfunction is associated with retinal degeneration and blindness. In order to fully understand how dysregulation affects visual function, RPE-specific gene knockouts are indispensable. Since the currently available RPE-specific Cre recombinases show lack of specificity or poor recombination, we sought to generate an alternative. We generated a tamoxifen-inducible RPE-specific Cre transgenic mouse line under transcriptional control of an RPE-specific Tyrosinase enhancer. We characterized the Cre-mediated recombinant expression by crossing our RPE-Tyrosinase-CreErT2 mouse line with the tdTo…

Nutraceutical Supplementation Ameliorates Visual Function, Retinal Degeneration, and Redox Status in rd10 Mice

2021

Background: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by progressive degeneration of photoreceptor cells. Ocular redox status is altered in RP suggesting oxidative stress could contribute to their progression. In this study, we investigated the effect of a mixture of nutraceuticals with antioxidant properties (NUT) on retinal degeneration in rd10 mice, a model of RP. Methods: NUT was orally administered to rd10 mice from postnatal day (PD) 9 to PD18. At PD18 retinal function and morphology were examined by electroretinography (ERG) and histology including TUNEL assay, immunolabeling of microglia, Müller cells, and poly ADP ribose polymers. Retinal r…

Peripherin-2 differentially interacts with cone opsins in outer segments of cone photoreceptors

2016

Peripherin-2 is a glycomembrane protein exclusively expressed in the light-sensing compartments of rod and cone photoreceptors designated as outer segments (OS). Mutations in peripherin-2 are associated with degenerative retinal diseases either affecting rod or cone photoreceptors. While peripherin-2 has been extensively studied in rods, there is only little information on its supramolecular organization and function in cones. Recently, we have demonstrated that peripherin-2 interacts with the light detector rhodopsin in OS of rods. It remains unclear, however, if peripherin-2 also binds to cone opsins. Here, using a combination of co-immunoprecipitation analyses, transmission electron micr…

Non-Rapid Eye Movement Sleep Parasomnias and Migraine: A Role of Orexinergic Projections

2018

Introduction: Sleep and migraine share a common pathophysiological substrate, although the underlying mechanisms are unknown. The serotonergic and orexinergic systems are both involved in the regulation of sleep/wake cycle, and numerous studies show that both are involved in the migraine etiopathogenesis. These two systems are anatomically and functionally interconnected. Our hypothesis is that in migraine a dysfunction of orexinergic projections on the median raphe (MR) nuclei, interfering with serotonergic regulation, may cause Non-Rapid Eye Movement parasomnias, such as somnambulism. Hypothesis/theory: Acting on the serotonergic neurons of the raphe nuclei, the dysfunction of orexinergic…

Th17 skewing in the GALT of a Crohn disease patient upon Lactobacillus rhamnosus GG consumption.

2015

We wish to report on a recent observation we made and that might represent a useful hint for the employment of the so called probiotics in the management of some pathological immune reactions of the gut. By analyzing GALT-associated T cells upon consumption of L. rhamnosus-GG, we obtained some hints that probiotics might have locoregional immunological effects mainly when administered in patients with IBDs rather than in individuals with non-inflamed gut mucosa.

Genetic 3’UTR variation is associated with human pigmentation characteristics and sensitivity to sunlight

2017

Sunlight exposure induces signalling pathways leading to the activation of melanin synthesis and tanning response. MicroRNAs (miRNAs) can regulate the expression of genes involved in pigmentation pathways by binding to the complementary sequence in their 3'untranslated regions (3'UTRs). Therefore, 3'UTR SNPs are predicted to modify the ability of miRNAs to target genes, resulting in differential gene expression. In this study, we investigated the role in pigmentation and sun-sensitivity traits, as well as in melanoma susceptibility, of 38 different 3'UTR SNPs from 38 pigmentation-related genes. A total of 869 individuals of Spanish origin (526 melanoma cases and 343 controls) were analysed.…