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Romagnolo, A.

Publications and source records attributed to Romagnolo, A..

3 recordsLinked to original sources

Plasmatic immune extracellular vesicle profiles identify prodromal and early stages of Parkinson's disease

Extracellular vesicles (EVs) hold promise as minimally invasive biomarkers for neurodegenerative proteinopathies, but disease- and stage-specific profiles remain unclear. For this study, we enrolled 378 participants across five centers and the MJFF-BioFIND cohort: 100 healthy controls [HC], 64 isolated REM sleep behavior disorder [iRBD], 41 DeNovo Parkinsons Disease [PD], 89 Late PD, 32 other Synucleinopathies, and 52 Tauopathies. All participants underwent clinical evaluation and blood collection. The 77 subjects from the BioFIND cohort also provided CSF samples. EV concentration and size were assessed by nanoparticle tracking analysis; flow cytometry quantified tetraspanins (CD9/CD63/CD81) and 37 surface markers. Multivariable logistic regression, receiver operating characteristic analyses (ROC), and repeated random forest (rRF) classifiers evaluated diagnostic utility. Late PD showed the highest EV concentrations compared to HC and other disease groups. Participants exhibited distinct EV surface immunophenotypes, with the iRBD group displaying the most extensive immune activation signature vs HC, followed by PD patients. Multivariate logistic regression analysis identified diagnostic marker panels: CD3/CD9/CD25/CD56 for iRBD, SSEA4 for Late PD, CD146/CD209 for Synucleinopathies, and CD8/CD45/CD62P for Tauopathies. ROC confirmed good discriminatory performance, with CD56 emerging as the strongest single predictor for iRBD vs HC, SSEA4 showing high sensitivity for Late PD, and marker combinations providing optimal balance for Synucleinopathy/Tauopathy classification vs HC. In the CSF BioFIND subset, Late PD EVs exhibited increased myeloid (CD1c), adhesion (CD29), activation (CD69), and epithelial (CD326) markers compared to HC. Among these, CD326 was independently associated with Late PD diagnosis. Machine learning classifiers using all 37 surface antigens achieved excellent training performance (91.7-94.3% accuracy for iRBD/Synucleinopathies vs HC) and maintained robust validation accuracy, particularly for iRBD (77.8%) and DeNovo PD (76.6%) vs HC. EV immuno-phenotyping reveals distinct signatures across the neurodegenerative proteinopathies spectrum, with the highest diagnostic utility for prodromal iRBD detection. Longitudinal validation and cell-of-origin refinement represent key next steps toward clinical translation.

neuroscience↗

Chronic exposure to low-concentration urban PM2.5 accelerates maladaptive repair after ischemic injury via mitochondrial dysfunction and lysosomal stress.

BackgroundFine particulate matter (PM2.5), airborne particles with an aerodynamic diameter [&le;]2.5 m that can penetrate deep into the lungs and enter the circulation, is increasingly recognized as a risk factor for chronic kidney disease (CKD) with long-term exposure. We previously demonstrated that high-dose PM2.5 exposure prior to ischemia-reperfusion injury (IRI) aggravates acute kidney injury (AKI). Here, we investigated how prolonged, low-concentration urban PM2.5 exposure (<15 {micro}g/m3) affects kidney repair after AKI. MethodsSix-week-old mice underwent bilateral IRI or sham surgery, followed by six months of exposure to either filtered air or ambient PM2.5 exposure in a unique exposome chamber. Kidneys were analyzed using pathomics, electron and super-resolution microscopy, immunohistochemistry, transcriptomics, and LC-MS lipidomics/metabolomics. Complementary in vitro hypoxia-reoxygenation and PM2.5 exposure experiments were performed in proximal tubular epithelial cells. ResultsLong-term PM2.5 exposure had minimal effects in sham-operated mice, including no significant changes in body weight or kidney function. Despite preserved kidney function, IRI+PM2.5 mice exhibited reduced weight gain, a marked expansion of the interstitial area, attributable to enhanced fibrosis and inflammatory responses, microvascular rarefaction, and endothelial-to-mesenchymal transition, consistent with maladaptive repair features. Proximal tubules displayed mitochondrial injury, glycolytic reprogramming, lipid accumulation, and a senescent phenotype. Energy Dispersive X-ray (EDX) microscopy confirmed PM2.5-derived elements within proximal tubules lysosomes, accompanied by lysosomal stress. Transcriptional signature-based drug screening identified nicotinamide as a compound capable of reversing PM2.5-induced metabolic alterations; in vitro validation confirmed restoration of mitochondrial function. ConclusionsTogether, these findings show that chronic post-AKI exposure to PM2.5 at levels currently considered safe by regulatory bodies drives maladaptive repair and accelerates CKD progression through mitochondrial dysfunction, lysosomal stress senescence in proximal tubules, due to local PM2.5 element accumulation. Translational StatementAcute kidney injury frequently progresses to chronic kidney disease due to maladaptive repair, yet environmental drivers of this transition remain underrecognized. Using a controlled exposome chamber, we demonstrate that chronic exposure to low, real-world concentrations of urban PM2.5 during post-ischemic recovery results in the accumulation of PM2.5-derived elements within proximal tubular lysosomes, leading to organelle dysfunction, metabolic reprogramming, lipid accumulation, and a senescence-like phenotype. Importantly, transcriptomics-based drug repurposing identified nicotinamide as a candidate compound capable of reversing metabolic dysfunction in injured proximal tubular cells subjected to hypoxia-reoxygenation and PM2.5 exposure, an effect validated in vitro.

molecular biology↗

Trait impulsivity and response-inhibition in Parkinson Disease. An fMRI study.

IntroductionDopamine agonists and levodopa have been implicated in impulse-control disorder (ICD) development since they can induce alterations in the frontostriatal network that manage reward and mediate impulse monitoring and control. The aim the study was to explore the response-inhibition performance and the neural correlates of inhibition in Parkinsons disease (PD) patients that varied on self-reported trait impulsivity.\n\nMethodsTen cognitively non-impaired patients with PD were recruited. They underwent a neurological evaluation, a neuropsychological assessment and questionnaires on behavioral mood changes. The Barratt Impulsiveness Scale (BISS-11) provided an integrated measure of trait impulsivity. During an fMRI acquisition, each subject was asked to perform a GO-NOGO task. Associations between BOLD response of the whole brain during the response-inhibition task and trait impulsivity were investigated.\n\nResultsPatients with greater scores on BIS-11 had greater activation of the bilateral presupplementary motor area (pre-SMA), bilateral anterior insula, right anterior cingulate cortex, and right temporal parietal junction (TPJ) during response-inhibition. Moreover, a significant association between higher impulsivity scores and worse performance was present (p= 0.038).\n\nConclusionsOur results suggest that deficit in inhibitory processes may affect everyday life, causing impulsive conduct, which is generally detrimental for PD patients. The strong association between BIS-11 scores, MPFC, pre-SMA and TPJ suggests that greater engagement of that network was needed to maintain behavioral inhibition in more impulsive PD patients. Indeed, neuroimaging of brain activity during GO-NOGO task may be useful in characterizing the clinical profile while evaluating the treatment options.\n\nFinancial disclosure/Conflict of interest concerning the research related to the manuscript: No conflicts of interest/ financial disclosures considering all the authors.\n\nFunding sources: this research was not funded by any commercial or governmental agency.

neuroscience↗