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Loria, F.

Publications and source records attributed to Loria, F..

5 recordsLinked to original sources

Investigating the effect of ginger-derived nanovesicles on the growth and metabolic activity of Bacteroides thetaiotaomicron: an isothermal microcalorimetric study

Plant-derived extracellular vesicles (EVs) have shown numerous health benefits, including modulation of the human gut microbiota. Hereby, we employed isothermal microcalorimetry (IMC) to explore the effects of ginger-derived nanovesicles (G-NVs) on the growth and metabolic activity of Bacteroides thetaiotaomicron (Bt), a dominant saccharolytic commensal with promising next-generation probiotic potential. Bt was exposed to either G-NVs or the ginger extract separated from G-NVs (G-CTL) in defined media under anaerobic conditions. Both ginger samples enhanced bacterial specific growth rate and maximum metabolic activity, inducing the latter earlier. However, higher biomass production and greater secretion of acetic, succinic, and propionic acids occurred only in response to the G-CTL. Complete sugar depletion and unchanged FAA levels indicated preferential carbohydrate utilization by Bt. Overall, these findings revealed that Bts metabolic state is shaped by both G-NVs and G-CTL, yet through distinct mechanisms, with G-NVs inducing rapid stimulation without increasing total metabolic output and G-CTL providing a sustained, dose-dependent effect. To our knowledge, this is the first study applying IMC to monitor real-time the impact of EVs on microbial growth and metabolism, underscoring IMCs utility for mechanistic studies of EV-microbe interactions. Furthermore, this research sets the ground for innovative strategies in nutraceutical and microbiome-targeted therapy development.

microbiology↗

Glial cell activation precedes neurodegeneration in the cerebellar cortex of the YG8-800 murine model of Friedreich's ataxia

Friedreichs ataxia is a hereditary neurodegenerative disorder resulting from reduced levels of the protein frataxin due to an expanded GAA repeat in the FXN gene. This deficiency causes progressive degeneration of specific neuronal populations in the cerebellum and the consequent loss of movement coordination and equilibrium, some of the main symptoms observed in affected individuals. Similar to other neurodegenerative diseases, previous studies suggest that glial cells could be involved in the neurodegenerative process and disease progression in Friedreichs ataxia. In this work, we have followed and characterized the progression of changes in the cerebellar cortex of the latest Friedreichs ataxia humanized mouse model, the YG8-800 (Fxnnull:YG8s(GAA)>800), which carries a human FXN transgene containing more than 800 GAA repeats. Comparative analyses of behavioral, histopathological, and biochemical parameters were conducted between Y47R control and YG8-800 mice at different time points. Our findings revealed that the YG8-800 mice display an ataxic phenotype, characterized by poor motor coordination, lower body weight, cerebellar atrophy, neuronal loss, and changes in synaptic proteins. Additionally, early activation of glial cells, predominantly astrocytes and microglia, was observed preceding neuronal degeneration along with an increased expression of key pro-inflammatory cytokines and downregulation of neurotrophic factors. Together, our results show how the YG8-800 mouse model exhibits a stronger phenotype than previous experimental murine models, reliably recapitulating some of the features observed in the human condition. Accordingly, this humanized model could represent a valuable tool to study Friedreichs ataxia molecular disease mechanisms and for preclinical evaluation of possible therapies.

neuroscience↗

A decision-making tool to navigate through Extracellular Vesicle research and product development

Due to their intercellular communication properties and their involvement in a wide range of biological processes, extracellular vesicles (EVs) are increasingly being studied and exploited for different applications. Nevertheless, their complex nature and heterogeneity, as well as the challenges related to their isolation, purification and characterization procedures, require cautious assessment of the quality and quantity parameters to monitor. This translates into a multitude of choices and putative solutions that lie in front of any EV researcher, in both research and translational environments, resembling a labyrinth with multiple paths to cross and, possibly, more than one exit. In this respect, decision-making tools might represent our modern Ariadnes string to follow not to get lost or distracted along the journey, to choose the shorter and best-fit-to-source EV application(s) and vice versa. Here, we present the implementation of a multi-criteria EV decision-making grid (EV-DMG) as a novel, customizable, efficient and easy-to-use tool to support responsible EV research and innovation. By identifying and weighting key assessment criteria for comparing distinct EV-based preparations and/or processes, our EV-DMG may assist any EV community member in making informed, transparent and reproducible decisions regarding the EV sources and/or samples to be managed, as well as the most suitable production and/or analytical pipelines to be adopted for targeting a defined aim or application.

cell biology↗

Novel loading protocol combines highly efficient encapsulation of exogenous therapeutic toxin with preservation of extracellular vesicles properties, uptake and cargo activity

Extracellular vesicles (EVs) have mostly been investigated as carriers of biological therapeutics such as proteins and RNA. Nevertheless, small-molecule drugs of natural or synthetic origin have also been loaded into EVs, resulting in an improvement of their therapeutic properties. A few methods have been employed for EV cargo loading, but poor yield and drastic modifications of vesicles remain unsolved challenges. We tested a different strategy based on temporary pH alteration through incubation of EVs with alkaline sodium carbonate, which resulted in conspicuous exogenous molecule incorporation. In-depth characterization showed that vesicle size, morphology, composition, and uptake were not affected. Our method was more efficient than gold-standard electroporation, particularly for a potential therapeutic toxin: the plant Ribosome Inactivating Protein saporin. The encapsulated saporin resulted protected from degradation, and was efficiently conveyed to receiving cancer cells and triggered cell death. EV-delivered saporin was more cytotoxic compared to the free toxin. This approach allows both the structural preservation of vesicle properties and the transfer of protected cargo in the context of drug delivery.

cancer biology↗

AFM-based High-Throughput Nanomechanical Screening of Single Extracellular Vesicles

We herein describe an Atomic Force Microscopy (AFM)-based experimental procedure which allows the simultaneous mechanical and morphological characterization of several hundred individual nanosized vesicles within the hour timescale. When deposited on a flat rigid surface from aqueous solution, vesicles are deformed by adhesion forces into oblate spheroids whose geometry is a direct consequence of their mechanical stiffness. AFM image analysis can be used to quantitatively measure the contact angle of individual vesicles, which is a size-independent descriptor of their deformation and, consequently, of their stiffness. The same geometrical measurements can be used to infer vesicle diameter in its original, spherical shape. We demonstrate the applicability of the proposed approach to natural vesicles obtained from different sources, recovering their size and stiffness distributions by simple AFM imaging in liquid. We show how the combined EV stiffness/size readout is able to discriminate between subpopulations of vesicular and non-vesicular objects in the same sample, and between populations of vesicles with similar sizes but different mechanical characteristics. We also discuss a force spectroscopy calibration procedure to quantitatively link the stiffness of EVs to their average contact angle. Finally, we discuss expected extensions and applications of the methodology.

biophysics↗