Biology subjects

Salvati, A.

Publications and source records attributed to Salvati, A..

4 recordsLinked to original sources

bioRxiv2024

Berberine Bridge enzyme-like oxidases orchestrate homeostatic control and signaling of oligogalacturonides in defense and wounding

Plant immunity is triggered by endogenous elicitors known as damage-associated molecular patterns (DAMPs). Oligogalacturonides (OGs) are DAMPs released from the cell wall (CW) demethylated homogalacturonan during microbial colonization, mechanical or pest-provoked tissue damage, and physiological CW remodeling. Berberine Bridge Enzyme-like (BBE-l) proteins named OG oxidases (OGOXs) have been proposed to govern OGs homeostasis, which is necessary to avoid deleterious growth-affecting hyper-immunity and possible cell death. Using OGOX1 over-expressing lines and ogox1/2 double mutants, we show that these enzymes determine the levels of active OGs vs. inactive oxidized products (oxOGs). The ogox1/2-deficient plants have elevated levels of OGs, while plants overexpressing OGOX1 accumulate oxOGs. The balance between OGs and oxOGs affect disease resistance against Pseudomonas syringae pv tomato, Pectobacterium carotovorum, and Botrytis cinerea depending on the microbial capacity to respond to OGs and metabolize oxOGs. Gene expression upon plant infiltration with OGs reveals that OGOXs orchestrate OG signaling in defense as well as upon tissue damage, pointing to these enzymes as apoplastic players in immunity and tissue repair. TeaserOxidases control the homeostasis of oligogalacturonides in the cell wall and play a pivotal role in the plant immunity.

plant biology↗

bioRxiv2024

Olive mill wastewater as a source of by-products promoting plant defense against microbial pathogens

Olive oil is a core component of the Mediterranean diet known for its nutritional properties and health benefits. Olive industry is moving to novel extraction systems for higher oil yield and quality and for waste reduction, which is a relevant problem in the process due to its toxicity and high disposal costs. Multi-Phase Decanter (DMF) is a modern two-phase system performed without adding water during the process. Using DMF, a wet by-product indicated as pate and consisting of the fruit pulp and vegetation water (VW) is recovered. The pate has a high content of potentially bioactive molecules that may be exploited to promote plant resistance against microbial pathogens. In this work, to identify by/products of biological interest, the VW recovered from the pate by centrifugation was subjected to fractionation by tangential-flow membrane filtration (TFMF), combining microfiltration (MF) and ultrafiltration (UF). High-resolution NMR spectroscopy indicated the presence of bioactive molecules such as flavonoids, hydroxytyrosol and oleuropein with known antimicrobial activity. High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD) was performed to detect the presence of pectic oligosaccharides in the fractions, showing the enrichment, in the UF-concentrate fraction, of oligogalacturonides (OGs), well known for the ability to elicit defense responses and protect plants against pathogen infections. Arabidopsis thaliana plants treated with TFMF fractions displayed induction of defense responses and exhibited resistance against microbial pathogens without adverse effects on growth and fitness. This study shows that pate by-products can potentially be exploited in agriculture as sustainable plant phyto-protectant. Graphical abstract(image created with BioRender)

plant biology↗

bioRxiv2023

Glucose deprivation promotes pseudo-hypoxia and de-differentiation in lung adenocarcinoma

Increased utilization of glucose is a hallmark of cancer. Several studies are investigating the efficacy of glucose restriction by glucose transporter blockade or glycolysis inhibition. However, the adaptations of cancer cells to glucose restriction are unknown. Here, we report the discovery that glucose restriction in lung adenocarcinoma (LUAD) induces cancer cell de-differentiation, leading to a more aggressive phenotype. Glucose deprivation causes a reduction in alpha-ketoglutarate (KG), leading to attenuated activity of KG-dependent histone demethylases and histone hypermethylation. We further show that this de-differentiated phenotype depends on unbalanced EZH2 activity, causing inhibition of prolyl-hydroxylase PHD3 and increased expression of hypoxia inducible factor 1 (HIF1), triggering epithelial to mesenchymal transition. Finally, we identified an HIF1-dependent transcriptional signature with prognostic significance in human LUAD. Our studies further current knowledge of the relationship between glucose metabolism and cell differentiation in cancer, characterizing the epigenetic adaptation of cancer cells to glucose deprivation and identifying novel targets to prevent the development of resistance to therapies targeting glucose metabolism.

cancer biology↗

bioRxiv2021

Inhalable textile microplastic fibers impair airway epithelial growth

Synthetic textiles shed fibers that accumulate indoors and this results in continuous exposure when indoors. High exposure to microplastic fibers in nylon flock workers has been linked to the development of airway and interstitial lung disease, but the exact health effects of microplastic fibers on the lungs are unknown. Here we determined effects of polyester and nylon textile microplastic fibers on airway and alveolar epithelial cells using human and murine lung organoids. We observed that particularly nylon microfibers had a negative impact on the growth and development of airway organoids. We demonstrated that this effect was mediated by components leaking from nylon. Moreover, our data suggested that microplastic textile fibers may especially harm the developing airways or airways undergoing repair. Our results call for a need to assess exposure and inhalation levels in indoor environments to accurately determine the actual risk of these fibers to human health. TeaserAirborne fibers shed from synthetic textiles, in particular nylon, can inhibit repair of the cells coating the airways

pharmacology and toxicology↗