Search bioRxiv⌕ Search

Biology subjects

Marola, O.

Publications and source records attributed to Marola, O..

3 recordsLinked to original sources

Crop-OCT: a Fully Integrated Imageomics Pipeline to Identify Regional and Focal Retinopathy in Murine Models

Imageomics uses machine learning to accelerate our understanding of biological traits and human disease processes. Some of the earliest imageomics applications used deep learning to assess human diseases. For example, retinal fundus images were analyzed to diagnose diabetic retinopathy. The imaging modality optical coherence tomography (OCT) is widely used to diagnose and monitor the progression of retinopathy in patients and preclinical models. The standardized instrumentation and image format of OCT lends itself to imageomics, but generalizable, automated pipelines for segmentation and quantitation of large numbers of OCT images are still in early development. Here, we present the automated, end-to-end pipeline Crop-OCT that extracts features from thousands of OCT images, while preserving their location within the eye. We used the Crop-OCT pipeline on a diverse dataset, including 13 genetic models of retinopathy, with more than 20,000 OCT images, which allowed us to analyze nearly 6 million measured features. The pipeline was generalized on an independent dataset that was analyzed in a blinded manner. The pipeline enabled us to monitor ocular changes associated with aging and progression of diseases, such as retinitis pigmentosa, Leber congenital amaurosis, achromatopsia, Stargardt disease, diabetic retinopathy, and age-related macular degeneration. We also characterized heterogeneity across animals and identified regional and focal lesions. Our pipeline will unify feature extraction for preclinical models of retinal disease and serve as a foundation for future multimodal data integration for artificial intelligence applications based on imageomics.

neuroscience↗

WSB.APP/PS1 mice develop age-dependent cerebral amyloid angiopathy, cerebrovascular deficits, and white matter damage, which are modified by humanized APOE alleles.

INTRODUCTIONGrowing evidence suggests cerebrovascular deficits, including cerebral amyloid angiopathy (CAA), play a key role in Alzheimers disease (AD) pathogenesis. However, these facets of AD are not well understood, due in part to the lack of mouse models that develop robust vascular deficits and CAA. Here, we characterize human-relevant cerebrovascular phenotypes in WSB.APP/PS1 mice with and without humanized APOE alleles. METHODSAD-relevant cerebrovascular phenotypes in WSB, WSB.APP/PS1, WSB.APOE2/2APP/PS1, WSB.APOE3/3APP/PS1, and/or WSB.APOE4/4APP/PS1 mice were characterized using immunohistochemistry, transcriptomics, positron emission tomography/computed tomography, and ex-vivo analyses. RESULTSWSB.APP/PS1 mice exhibited age-related plaque deposition and CAA, significant transcriptomic overlap with human AD, myelin deficits, cerebrovascular/metabolic uncoupling, and altered cerebrovascular morphology. Aged WSB vasculature retained vasoreactivity, but exhibited increased stiffness. Compared to APOE2, APOE4 expression in WSB.APP/PS1 mice increased CAA and plaque-associated microglial area. DISCUSSIONThese data illustrate the utility of the WSB genetic context to model CAA and uncover vascular contributions to AD. HighlightsO_LIWSB.APP/PS1 mice developed CAA with age. C_LIO_LITranscriptomic profiling revealed significant molecular overlap between human AD and WSB.APP/PS1 brains. C_LIO_LITranscriptomics and immunofluorescence suggested age-related myelin deficits in WSB.APP/PS1 brains. C_LIO_LIWSB.APP/PS1 brains exhibited neurovascular uncoupling, changes in vascular volume and surface area, and increased permeability changes. C_LIO_LIWSB.APP/PS1 cerebrovasculature was resilient to loss of responsivity with age but exhibited increased vascular stiffness. C_LIO_LIHumanized APOE {varepsilon}4 alleles significantly increased CAA and parenchymal plaque-associated microglial area in WSB.APP/PS1 mice. C_LI Research in ContextO_LISystematic review: The authors characterized WSB.APP/PS1 as a unique human-relevant model of Alzheimers Disease and explored several facets of cerebrovascular deficits. C_LIO_LIInterpretation: WSB and/or WSB.APP/PS1 mice exhibited human-relevant vascular phenotypes, including CAA, neurovascular uncoupling, increased vascular tree volume, vascular stiffness, and resilience to age-related loss of responsivity. Furthermore, the transcriptomic profile of WSB.APP/PS1 brains significantly overlaps with signatures observed in human AD. WSB.APP/PS1 brains exhibited myelin deficits with age. Furthermore, humanized APOE {varepsilon}2, {varepsilon}3, and {varepsilon}4 alleles significantly modified WSB.APP/PS1 susceptibility to CAA, plaque deposition, and plaque-associated microglial area. C_LIO_LIFuture Directions: The WSB genetic context will be leveraged to identify specific molecular mechanisms associated with cerebrovascular deficits in AD. C_LI

neuroscience↗

Neuronal protein phosphatase 1β regulates glutamate release, cortical myelination, node of Ranvier formation, and action potential propagation in the optic nerve

Precise regulation of protein phosphorylation is critical for many cellular processes, and dysfunction in this process has been linked to various neurological disorders and diseases. Protein phosphatase 1 (PP1) is a ubiquitously expressed serine/threonine phosphatase with three major isoforms, (, {beta}, {gamma}) and hundreds of known substrates. Previously, we reported that PP1 and PP1{gamma} are essential for the known role of PP1 in synaptic physiology and learning/memory, while PP1{beta} displayed a surprising opposing function. De novo mutations in PP1{beta} cause neurodevelopmental disorders in humans, but the mechanisms involved are currently unknown. A Cre-Lox system was used to delete PP1{beta} specifically in neurons in order to study its effects on developing mice. These animals fail to survive to 3 postnatal weeks, and exhibit deficits in cortical myelination and glutamate release. There was defective compound action potential (CAP) propagation in the optic nerve of the null mice, which was traced to a deficit in the formation of nodes of Ranvier. Finally, it was found that phosphorylation of the PP1{beta}-specific substrate, myosin light chain 2 (MLC2), is significantly enhanced in PP1{beta} null optic nerves. Several novel important in vivo roles of PP1{beta} in neurons were discovered, and these data will aid future investigations in delineating the mechanisms by which de novo mutations in PP1{beta} lead to intellectual and developmental delays in patients.

neuroscience↗