Search bioRxiv⌕ Search

Biology subjects

Brambilla, D.

Publications and source records attributed to Brambilla, D..

4 recordsLinked to original sources

GAL-101 prevents amyloid beta-induced membrane depolarization in two different types of retinal cells

Glaucoma and age-related macular degeneration (AMD) are two of the major causes of progressive vision loss and ultimately blindness worldwide. Both retinopathies share several pathological features with Alzheimers disease (AD) such as: impairment of neuronal function, astrocytosis, and activation of immune-competent microglia and Muller cells. It also has been shown that these conditions are characterized by the presence of an elevated concentration of amyloid beta (A{beta}). Under pathological conditions, A{beta}1-42 tends to aggregate, forming toxic soluble oligomers, considered to be the most harmful amyloid species. One strategy adopted to prevent cell damage caused by these oligomers is to impair their aggregation. Here we studied GAL-101, a small molecule designed to modify the aggregation of A{beta}1-42. To assess the role of GAL-101 in the aggregation of A{beta}1-42, in vitro electrophysiological measurements on retinal ganglion cells (RGCs) and retinal pigment epithelial (RPE) cells were performed to determine the polarization of the resting membrane potential. Cells treated only with A{beta}1-42 oligomers showed a strong depolarization of the resting membrane potential, which is believed to be the main reason for retinal cells malfunctioning in neurodegenerative diseases of the eye. Pre-incubation with GAL-101 stabilized the cell resting potential to around -50mV during exposure to A{beta}1-42, in both RGCs and RPE cells. GAL-101 was able to prevent changes in resting membrane potential and thus would be expected to prevent impairment of retinal cell function. These results are supportive of evaluating GAL-101 as a potential treatment of A{beta}-associated retinopathies like glaucoma and dry AMD.

neuroscience↗

Lipid-based nanoparticles deliver mRNA to reverse the pathogenesis of lysosomal acid lipase deficiency in a preclinical model

Lysosomal acid lipase (LAL) is the only known enzyme that degrades cholesteryl esters (CEs) and triglycerides (TGs) in the lysosomes. LAL deficiency (LAL-D) results in hepatosplenomegaly with extensive accumulation of CEs and TGs, and can in the most severe cases be a life-threatening condition in early infancy. Using messenger ribonucleic acid (mRNA) for protein replacement is an innovative approach for the treatment of genetic disorders, but is challenged by a safe and efficient mRNA delivery. Here, we generated a combinatorial library of lipid-based nanoparticles (LNPs) for mRNA delivery and screened it in vitro and in vivo, which yielded a new formulation with a superior potency than an FDA-approved nanoformulation. This formulation efficiently delivered LAL mRNA and restored LAL activity in liver and spleen, mediating significant reversal of the pathological progression in an aggressive preclinical model of LAL-D. In vivo, the new formulation also promoted a more sustained and quantitatively higher LAL expression. In addition, repeated administration regimen mitigated hepatosplenomegaly, and targeted lipidomic analysis revealed strong diminution of CEs and TGs and of toxic lipid species in the liver and spleen. Transcriptomic analysis showed significant attenuation of inflammatory processes, fibrosis and several pathological pathways associated to LAL-D. These findings provide strong evidence that the intracellular production of LAL via mRNA-LNP is a very promising approach for the chronic treatment of LAL-D and support the clinical translation of mRNA therapy to overcome the challenges associated with traditional enzyme replacement therapies. One Sentence SummaryScreening of a mRNA-LNPs library yielded a formulation with outmost potency and mitigated the progression of LAL deficiency in a preclinical model.

bioengineering↗

CureSCi Metadata Catalog - Making sickle cell studies findable

ObjectivesTo adopt the FAIR principles (Findable, Accessible, Interoperable, Reusable) to enhance data sharing, the Cure Sickle Cell Initiative (CureSCi) MetaData Catalog (MDC) was developed to make Sickle Cell Disease (SCD) study datasets more Findable by curating study metadata and making them available through an open-access web portal. MethodsStudy metadata, including study protocol, data collection forms, and data dictionaries, describe information about study patient-level data. We curated key metadata of 16 SCD studies in a three-tiered conceptual framework of category, subcategory, and data element using ontologies and controlled vocabularies to organize the study variables. We developed the CureSCi MDC by indexing study metadata to enable effective browse and search capabilities at three levels: study, Patient-Reported Outcome (PRO) Measures, and data element levels. ResultsThe CureSCi MDC offers several browse and search tools to discover studies by study level, PRO Measures, and data elements. The "Browse Studies," "Browse Studies by PRO Measures," and "Browse Studies by Data Elements" tools allow users to identify studies through pre-defined conceptual categories. "Search by Keyword" and "Search Data Element by Concept Category" can be used separately or in combination to provide more granularity to refine the search results. This resource helps investigators find information about specific data elements across studies using public browsing/search tools, before going through data request procedures to access controlled datasets. The MDC makes SCD studies more Findable through browsing/searching study information, PRO Measures, and data elements, aiding in the reuse of existing SCD data.

bioinformatics↗

Three-dimensional Printing of Customized Bioresorbable Airway Stents

Central airway obstruction is a life-threatening disorder causing a high physical and psychological burden to patients due to severe breathlessness and impaired quality of life. Standard-of-care airway stents are silicone tubes, which cause immediate relief, but are prone to migration, especially in growing patients, and require additional surgeries to be removed, which may cause further tissue damage. Customized airway stents with tailorable bioresorbability that can be produced in a reasonable time frame would be highly needed in the management of this disorder. Here, we report poly(D,L-lactide-co-{varepsilon}-caprolactone) methacrylate blends-based biomedical inks and their use for the rapid fabrication of customized and bioresorbable airway stents. The 3D printed materials are cytocompatible and exhibit silicone-like mechanical properties with suitable biodegradability. In vivo studies in healthy rabbits confirmed biocompatibility and showed that the stents stayed in place for 7 weeks after which they became radiographically invisible. The developed biomedical inks open promising perspectives for the rapid manufacturing of the customized medical devices for which high precision, tuneable elasticity and predictable degradation are sought-after.

bioengineering↗