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Ophthalmology Science 2024To determine the clinical characteristics of familial exudative vitreoretinopathy (FEVR) associated with or without pathogenic variants of the Norrin/β-catenin genes.
PURPOSE
To determine the clinical characteristics of familial exudative vitreoretinopathy (FEVR) associated with or without pathogenic variants of the Norrin/β-catenin genes.
DESIGN
This was a multicenter, cross-sectional, observational, and genetic study.
SUBJECTS
Two-hundred eighty-one probands with FEVR were studied.
METHODS
Whole-exome sequence and/or Sanger sequence was performed for the Norrin/β-catenin genes, the , , , and genes on blood collected from the probands. The clinical symptoms of the probands with or without the pathogenic variants were assessed as well as differences in the inter Norrin/β-catenin genes.
MAIN OUTCOME MEASURES
The phenotype associated with or without pathogenic variants of the Norrin/β-catenin genes.
RESULTS
One-hundred eight probands (38.4%) had 88 different pathogenic or likely pathogenic variants in the genes: 24 with the , 42 with the , 10 with the , and 12 with the gene. Compared with the 173 probands without pathogenic variants, the 108 variant-positive probands had characteristics of familial predisposition (63.9% vs. 37.6%, < 0.0001), progression during infancy (75.0% vs. 53.8%, = 0.0004), asymmetrical severity between the 2 eyes (50.0% vs. 37.6%, = 0.0472), and nonsyndromic characteristics (10.2% vs. 17.3%, = 0.1185). The most frequent stage at which the more severe eye conditions was present was at stage 4 in both groups (40.7% vs. 34.7%). However, the advanced stages of 3 to 5 in the more severe eye were found more frequently in probands with variants than in those without variants (83.3% vs. 58.4%, < 0.0001). Patients with rhegmatogenous retinal detachments progressed from stage 1 or 2 were found less frequently in the variant-positive probands (8.3% vs. 17.3%, = 0.0346). Nine probands with variants had features different from probands with typical Norrin/β-catenin gene variants including the sporadic, symmetrical, and systemic characteristics consistent with Norrie disease.
CONCLUSIONS
The results showed that the clinical characteristics of FEVR of patients with variants in the Norrin/β-catenin genes are different from those with other etiologies. We recommend that clinicians who diagnose a child with FEVR perform genetic testing so that the parents can be informed on the prognosis of the vision and general health in the child.
FINANCIAL DISCLOSURES
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
PubMed: 38881609
DOI: 10.1016/j.xops.2024.100514 -
Endocrine Journal Jun 2024The endometrium during the sexual cycle undergoes detachment, tissue remodeling, and differentiation during the menstrual cycle. Localized and transient destruction and...
The endometrium during the sexual cycle undergoes detachment, tissue remodeling, and differentiation during the menstrual cycle. Localized and transient destruction and regeneration of endometrial tissue are also essential for pregnancy. It is possible to attribute many causes of failure in infertility treatment to the implantation stage. To improve the success rate of plateau fertility treatment, it is important to understand the regeneration mechanism of the endometrium, a unique regenerative tissue in the human body. In association with cell proliferation, tissue remodeling requires the relocation of proliferative cells, and the steady-state epithelial cells need to be motile for the relocation. Transient add-on motile activity in epithelial cells is mediated by epithelial to mesenchymal transition (EMT) and reversible mesenchymal to epithelial transition (MET). The destruction and regeneration of endometrial tissue over a period of days to weeks requires a system with a rapid and characteristic mechanism similar to that of wound healing. Here, I review the relationship between the well-known phenomenon of EMT in wound healing and endometrial tissue remodeling during the sexual cycle and pregnancy establishment, which are automatically triggered by menstruation and embryonal invasion.
PubMed: 38880606
DOI: 10.1507/endocrj.EJ24-0229 -
Journal of Lipid Research Jun 2024Apolipoprotein AV (APOA5) deficiency causes hypertriglyceridemia in mice and humans. For years, the cause remained a mystery, but the mechanisms have now come into... (Review)
Review
Apolipoprotein AV (APOA5) deficiency causes hypertriglyceridemia in mice and humans. For years, the cause remained a mystery, but the mechanisms have now come into focus. Here, we review progress in defining APOA5's function in plasma triglyceride metabolism. Biochemical studies revealed that APOA5 binds to the angiopoietin-like protein 3/8 complex (ANGPTL3/8) and suppresses its ability to inhibit the activity of lipoprotein lipase (LPL). Thus, APOA5 deficiency is accompanied by increased ANGPTL3/8 activity and lower levels of LPL activity. APOA5 deficiency also reduces amounts of LPL in capillaries of oxidative tissues (e.g., heart, brown adipose tissue). Cell culture experiments revealed the likely explanation: ANGPTL3/8 detaches LPL from its binding sites on the surface of cells, and that effect is blocked by APOA5. Both the low intracapillary LPL levels and the high plasma triglyceride levels in Apoa5 mice are normalized by recombinant APOA5. Carboxyl-terminal sequences in APOA5 are crucial for its function; a mutant APOA5 lacking 40-carboxyl-terminal residues cannot bind to ANGPTL3/8 and lacks the ability to change intracapillary LPL levels or plasma triglyceride levels in Apoa5 mice. Also, an antibody against the last 26 amino acids of APOA5 reduces intracapillary LPL levels and increases plasma triglyceride levels in wild-type mice. An inhibitory ANGPTL3/8-specific antibody functions as an APOA5-mimetic reagent, increasing intracapillary LPL levels and lowering plasma triglyceride levels in both Apoa5 and wild-type mice. That antibody is a potentially attractive strategy for treating elevated plasma lipid levels in human patients.
PubMed: 38880127
DOI: 10.1016/j.jlr.2024.100578 -
Journal of Neuroscience Methods Jun 2024Ependymal cilia play a major role in the circulation of cerebrospinal fluid. Although isolation of cilia is an essential technique for investigating ciliary structure,...
BACKGROUND
Ependymal cilia play a major role in the circulation of cerebrospinal fluid. Although isolation of cilia is an essential technique for investigating ciliary structure, to the best of our knowledge, no report on the isolation and structural analysis of ependymal cilia from mouse brain is available.
NEW METHOD
We developed a novel method for isolating ependymal cilia from mouse brain ventricles. We isolated ependymal cilia by partially opening the lateral ventricles and gently applying shear stress, followed by pipetting and ultracentrifugation.
RESULTS
Using this new method, we were able to observe cilia separately. The results demonstrated that our method successfully isolated intact ependymal cilia with preserved morphology and ultrastructure. In this procedure, the ventricular ependymal cell layer was partially detached.
COMPARISON WITH EXISTING METHODS
Compared to existing methods for isolating cilia from other tissues, our method is meticulously tailored for extracting ependymal cilia from the mouse brain. Designed with a keen understanding of the fragility of the ventricular ependyma, our method prioritizes minimizing tissue damage during the isolation procedure.
CONCLUSIONS
We isolated ependymal cilia from mouse brain by applying shear stress selectively to the ventricles. Our method can be used to conduct more detailed studies on the structure of ependymal cilia.
PubMed: 38878975
DOI: 10.1016/j.jneumeth.2024.110198 -
Cell Jun 2024Inflammation-induced neurodegeneration is a defining feature of multiple sclerosis (MS), yet the underlying mechanisms remain unclear. By dissecting the neuronal...
Inflammation-induced neurodegeneration is a defining feature of multiple sclerosis (MS), yet the underlying mechanisms remain unclear. By dissecting the neuronal inflammatory stress response, we discovered that neurons in MS and its mouse model induce the stimulator of interferon genes (STING). However, activation of neuronal STING requires its detachment from the stromal interaction molecule 1 (STIM1), a process triggered by glutamate excitotoxicity. This detachment initiates non-canonical STING signaling, which leads to autophagic degradation of glutathione peroxidase 4 (GPX4), essential for neuronal redox homeostasis and thereby inducing ferroptosis. Both genetic and pharmacological interventions that target STING in neurons protect against inflammation-induced neurodegeneration. Our findings position STING as a central regulator of the detrimental neuronal inflammatory stress response, integrating inflammation with glutamate signaling to cause neuronal cell death, and present it as a tractable target for treating neurodegeneration in MS.
PubMed: 38878778
DOI: 10.1016/j.cell.2024.05.031 -
Biophysical Journal Jun 2024Trypsin is a very common enzyme used in cell culture to harvest cells by cleaving the proteins responsible for cell adhesion. However, trypsin also induces undesirable...
Trypsin is a very common enzyme used in cell culture to harvest cells by cleaving the proteins responsible for cell adhesion. However, trypsin also induces undesirable effects on cells, such as altering membrane proteins and the cytoskeleton, changing the composition of the cytoplasm and the cell volume, and even leading to cell death when used improperly. Using attenuated total reflection in the terahertz domain, confocal microscopy, and the propidium iodide test, we quantified in real time the change in cytoplasmic content induced by trypsin proteolysis on Madin-Darby canine kidney epithelial cells. We have observed a cytoplasmic modification from the very first seconds of trypsinization, following the change of cell volume due to mechanical re-equilibrium of the membrane. We found that the cytoplasmic alteration is associated with a transfer of small solutes: electrolytes and metabolites. We also found a very good nonlinear correlation between the side effects monitored by terahertz sensing and the cell height, regardless of the dependence of the cell height on trypsin concentration and exposure time.
PubMed: 38877703
DOI: 10.1016/j.bpj.2024.06.011 -
Harmful Algae Jun 2024Ostreopsis spp. blooms have been occurring in the last two decades in the Mediterranean Sea in association with a variety of biotic and abiotic substrata (macroalgae,...
Ostreopsis spp. blooms have been occurring in the last two decades in the Mediterranean Sea in association with a variety of biotic and abiotic substrata (macroalgae, seagrasses, benthic invertebrates, sand, pebbles and rocks). Cells proliferate attached to the surfaces through mucilaginous trichocysts, which lump together microalgal cells, and can also be found in the plankton and on floating aggregates: such tychoplanktonic behavior makes the quantitative assessment of blooms more difficult than planktonic or benthic ones. Different techniques have been so far applied for quantifying cell abundances of benthic microalgae for research, monitoring and risk assessment purposes. In this context, the Benthic Dinoflagellates Integrator (BEDI), a non-destructive quantification method for benthic dinoflagellate abundances, was developed and tested within the EU ENPI-CBCMED project M3-HABs. This device allows mechanical detachment of cells without collecting the benthic substrate, providing an integrated assessment of both epiphytic and planktonic cells, i.e. of the number of cells potentially made available in the water volume from "resuspension" which could have harmful effects on other organisms (including humans). The present study confirms the effectiveness of the BEDI sampling device across different environments across the Mediterranean Sea and constitutes the first large-scale study of Ostreopsis spp. blooms magnitude in function of different macro- and meso‑habitat features across the basin.
Topics: Dinoflagellida; Mediterranean Sea; Harmful Algal Bloom; Environmental Monitoring; Microalgae; Seawater
PubMed: 38876529
DOI: 10.1016/j.hal.2024.102651 -
Proceedings of the National Academy of... Jun 2024Shear forces affect self-assembly processes ranging from crystallization to fiber formation. Here, the effect of mild agitation on amyloid fibril formation was explored...
Shear forces affect self-assembly processes ranging from crystallization to fiber formation. Here, the effect of mild agitation on amyloid fibril formation was explored for four peptides and investigated in detail for A[Formula: see text]42, which is associated with Alzheimer's disease. To gain mechanistic insights into the effect of mild agitation, nonseeded and seeded aggregation reactions were set up at various peptide concentrations with and without an inhibitor. First, an effect on fibril fragmentation was excluded by comparing the monomer-concentration dependence of aggregation kinetics under idle and agitated conditions. Second, using a secondary nucleation inhibitor, Brichos, the agitation effect on primary nucleation was decoupled from secondary nucleation. Third, an effect on secondary nucleation was established in the absence of inhibitor. Fourth, an effect on elongation was excluded by comparing the seeding potency of fibrils formed under idle or agitated conditions. We find that both primary and secondary nucleation steps are accelerated by gentle agitation. The increased shear forces facilitate both the detachment of newly formed aggregates from catalytic surfaces and the rate at which molecules are transported in the bulk solution to encounter nucleation sites on the fibril and other surfaces. Ultrastructural evidence obtained with cryogenic transmission electron microscopy and free-flow electrophoresis in microfluidics devices imply that agitation speeds up the detachment of nucleated species from the fibril surface. Our findings shed light on the aggregation mechanism and the role of detachment for efficient secondary nucleation. The results inform on how to modulate the relative importance of different microscopic steps in drug discovery and investigations.
Topics: Amyloid; Kinetics; Humans; Shear Strength; Protein Aggregates; Peptides; Alzheimer Disease
PubMed: 38875148
DOI: 10.1073/pnas.2322572121 -
Molecular Biology Reports Jun 2024Human Amniotic Membrane (hAM) is endowed with several biological activities and might be considered an optimal tool in surgical treatment for different ophthalmic...
BACKGROUND
Human Amniotic Membrane (hAM) is endowed with several biological activities and might be considered an optimal tool in surgical treatment for different ophthalmic pathologies. We pioneered the surgical use of hAM to treat retinal pathologies such as macular holes, tears, and retinal detachments, and to overcome photoreceptor damage in age-related macular degeneration. Although hAM contributed to improved outcomes, the mechanisms of its effects are not yet fully understood. The characterization and explanation of the effects of hAM would allow the adoption of this new natural product in different retinal pathologies, operative contexts, and hAM formulations. At this end, we studied the properties of a hAM extract (hAME) on the ARPE-19 cells.
METHODS AND RESULTS
A non-denaturing sonication-based technique was developed to obtain a suitable hAME. Viability, proliferation, apoptosis, oxidative stress, and epithelial-mesenchymal transition (EMT) were studied in hAME-treated ARPE-19 cells. The hAME was able to increase ARPE-19 cell viability even in the presence of oxidative stress (HO, TBHP). Moreover, hAME prevented the expression of EMT features, such as EMT-related proteins, fibrotic foci formation, and migration induced by different cytokines.
CONCLUSIONS
Our results demonstrate that the hAME retains most of the properties observed in the whole tissue by others. The hAME, other than providing a manageable research tool, could represent a cost-effective and abundant drug to treat retinal pathologies in the future.
Topics: Humans; Amnion; Cell Line; Retinal Pigment Epithelium; Cell Survival; Apoptosis; Oxidative Stress; Cell Proliferation; Epithelial-Mesenchymal Transition; Tissue Extracts
PubMed: 38874663
DOI: 10.1007/s11033-024-09647-7 -
Frontiers in Cell and Developmental... 2024The unicellular green alga, i, has played a central role in discovering much of what is currently known about the composition, assembly, and function of cilia and... (Review)
Review
The unicellular green alga, i, has played a central role in discovering much of what is currently known about the composition, assembly, and function of cilia and flagella. combines excellent genetics, such as the ability to grow cells as haploids or diploids and to perform tetrad analysis, with an unparalleled ability to detach and isolate flagella in a single step without cell lysis. The combination of genetics and biochemistry that is possible in has allowed many of the key components of the cilium to be identified by looking for proteins that are missing in a defined mutant. Few if any other model organisms allow such a seamless combination of genetic and biochemical approaches. Other major advantages of compared to other systems include the ability to induce flagella to regenerate in a highly synchronous manner, allowing the kinetics of flagellar growth to be measured, and the ability of flagella to adhere to glass coverslips allowing Intraflagellar Transport to be easily imaged inside the flagella of living cells, with quantitative precision and single-molecule resolution. These advantages continue to work in favor of as a model system going forward, and are now augmented by extensive genomic resources, a knockout strain collection, and efficient CRISPR gene editing. While has obvious limitations for studying ciliary functions related to animal development or organ physiology, when it comes to studying the fundamental biology of cilia and flagella, is simply unmatched in terms of speed, efficiency, cost, and the variety of approaches that can be brought to bear on a question.
PubMed: 38872931
DOI: 10.3389/fcell.2024.1412641