Alessandra Falleni

Dr. Alessandra Falleni

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Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Federica AnastasiFederica Anastasi
Federica Anastasi
SMSilvia Masciandaro
Silvia Masciandaro
RCRenata Del Carratore
Renata Del Carratore
MDMaria Teresa Dell’anno
Maria Teresa Dell’anno
Giovanni SignoreGiovanni Signore
Giovanni Signore
Paolo BongioanniPaolo Bongioanni
Paolo Bongioanni
Small extracellular vesicles have been intensively studied as a source of biomarkers in neurodegenerative disorders. The possibility to isolate neuron-derived small extracellular vesicles (NDsEV) from blood represents a potential window into brain pathological processes. To date, the absence of sensitive NDsEV isolation and full proteome characterization methods has meant their protein content has been underexplored, particularly for individual patients. Here, we report a rapid method based on an immunoplate covalently coated with mouse monoclonal anti-L1CAM antibody for the isolation and the proteome characterization of plasma-NDsEV from individual Parkinson’s disease (PD) patients. We isolated round-shaped vesicles with morphological characteristics consistent with exosomes. On average, 349 ± 38 protein groups were identified by liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis, 20 of which are annotated in the Human Protein Atlas as being highly expressed in the brain, and 213 were shared with a reference NDsEV dataset obtained from cultured human neurons. Moreover, this approach enabled the identification of 23 proteins belonging to the Parkinson disease KEGG pathway, as well as proteins previously reported as PD circulating biomarkers.

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Paola LenziPaola Lenzi
Paola Lenzi
RFRosangela Ferese
Rosangela Ferese
FBFrancesca Biagioni
Francesca Biagioni
FFFederica Fulceri
Federica Fulceri
CBCarla Letizia Busceti
Carla Letizia Busceti
Francesco FornaiFrancesco Fornai
Francesco Fornai
Glioblastoma (GBM) cells feature mitochondrial alterations, which are documented and quantified in the present study, by using ultrastructural morphometry. Mitochondrial impairment, which roughly occurs in half of the organelles, is shown to be related to mTOR overexpression and autophagy suppression. The novelty of the present study consists of detailing an mTOR-dependent mitophagy occlusion, along with suppression of mitochondrial fission. These phenomena contribute to explain the increase in altered mitochondria reported here. Administration of the mTOR inhibitor rapamycin rescues mitochondrial alterations. In detail, rapamycin induces the expression of genes promoting mitophagy (PINK1, PARKIN, ULK1, AMBRA1) and mitochondrial fission (FIS1, DRP1). This occurs along with over-expression of VPS34, an early gene placed upstream in the autophagy pathway. The topographic stoichiometry of proteins coded by these genes within mitochondria indicates that, a remarkable polarization of proteins involved in fission and mitophagy within mitochondria including LC3 takes place. Co-localization of these proteins within mitochondria, persists for weeks following rapamycin, which produces long-lasting mitochondrial plasticity. Thus, rapamycin restores mitochondrial status in GBM cells. These findings add novel evidence about mitochondria and GBM, while fostering a novel therapeutic approach to restore healthy mitochondria through mTOR inhibition.

6 November 2021 in Molecules
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AFAlessandra Falleni
Alessandra Falleni
SMStefania Moscato
Stefania Moscato
ASAntonietta R. M. Sabbatini
Antonietta R. M. Sabbatini
MBMargherita Bernardeschi
Margherita Bernardeschi
FBFrancesco Bianchi
Francesco Bianchi
LMLetizia Mattii
Letizia Mattii
Connexins (Cxs) are a family of membrane-spanning proteins, expressed in vertebrates and named according to their molecular weight. They are involved in tissue homeostasis, and they function by acting at several communication levels. Cardiac Cxs are responsible for regular heart function and, among them, Cx26 and Cx43 are widely expressed throughout the heart. Cx26 is present in vessels, as well as in cardiomyocytes, and its localization is scattered all over the cell aside from at the intercalated discs as is the case for the other cardiac Cxs. However, having been found in cardiomyocytes only recently, both its subcellular localization and its functional characterization in cardiomyocytes remain poorly understood. Therefore, in this study we aimed to obtain further data on the localization of Cx26 at the subcellular level. Our TEM immunogold analyses were performed on rat heart ventricles and differentiated H9c2 cardiac cell sections as well as on differentiated H9c2 derived extracellular vesicles. The results confirmed the absence of Cx26 at intercalated discs and showed the presence of Cx26 at the level of different subcellular compartments. The peculiar localization at the level of extracellular vesicles suggested a specific role for cardiac Cx26 in inter-cellular communication in an independent gap junction manner.

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RGroberta giannelli
roberta giannelli
PCPaola Canale
Paola Canale
RCRenata Del Carratore
Renata Del Carratore
AFAlessandra Falleni
Alessandra Falleni
MBMargherita Bernardeschi
Margherita Bernardeschi
Paolo BongioanniPaolo Bongioanni
Paolo Bongioanni
Thriving literature underlines white blood cell involvement in the inflammatory processes of Alzheimer’s Disease (AD). Among leukocytes, lymphocytes have been considered sentinels of neuroinflammation for years, but recent findings highlighted the pivotal role of neutrophils. Since neutrophils that infiltrate the brain through the brain vascular vessels may affect the immune function of microglia in the brain, a close investigation of the interaction between these cells is important in understanding neuroinflammatory phenomena and the immunological aftermaths that follow. This study aimed to observe how peripheral leukocyte features change at different stages of AD to identify potential molecular markers when the first features of pathological neurodegeneration arise. For this purpose, the examined patients were divided into Mild Cognitive Impairment (MCI) and severely impaired patients (DAT) based on their Cognitive Dementia Rating (CDR). The evaluation of the neutrophil-to-lymphocytes ratio and the morphology and function of leukocytes showed a close relationship between the ultrastructural and the molecular features in AD progression and suggested putative markers for the early stages of the disease.

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Manuela CabiatiManuela Cabiati
Manuela Cabiati
EREmioli Randazzo
Emioli Randazzo
LGLetizia Guiducci
Letizia Guiducci
AFAlessandra Falleni
Alessandra Falleni
ACAntonella Cecchettini
Antonella Cecchettini
SRSilvia Del Ry
Silvia Del Ry
Exosomes may contribute to the pathogenesis of obesity through their action as communication mediators. As we have previously demonstrated, in obese adolescents, some circulating miRNAs modified the C-type natriuretic peptide (CNP) expression and were associated with changes in metabolic functions. At present no data are available on miRNA transport by exosomes in this condition. To verify and compare the presence and the expression of CNP/NPR-B/NPR-C, and some miRNAs (miR-33a-3p/miR-223-5p/miR-142-5p/miRNA-4454/miRNA-181a-5p/miRNA-199-5p), in circulating exosomes obtained from the same cohort of obese (O, n = 22) and normal-weight adolescents (N, n = 22). For the first time, we observed that exosomes carried CNP and its specific receptors only randomly both in O and N, suggesting that exosomes are not important carriers for the CNP system. On the contrary, exosomal miRNAs resulted ubiquitously and differentially expressed in O and N. O showed a significant decrease (p < 0.01) in the expression of all miRNAs except for miR-4454 and miR-142-5p. We have found significant correlations among miRNAs themselves and with some inflammatory/metabolic factors of obesity. These relationships may help in finding new biomarkers, allowing us to recognize, at an early stage, obese children and adolescents at high risk to develop the disease complications in adult life.

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ECElisa Ceccherini
Elisa Ceccherini
EPElisa Persiani
Elisa Persiani
Manuela CabiatiManuela Cabiati
Manuela Cabiati
LGLetizia Guiducci
Letizia Guiducci
SRSilvia Del Ry
Silvia Del Ry
FVFederico Vozzi
Federico Vozzi
Vascular calcification (VC) is a cardiovascular disease characterized by calcium salt deposition in vascular smooth muscle cells (VSMCs). Standard in vitro models used in VC investigations are based on VSMC monocultures under static conditions. Although these platforms are easy to use, the absence of interactions between different cell types and dynamic conditions makes these models insufficient to study key aspects of vascular pathophysiology. The present study aimed to develop a dynamic endothelial cell–VSMC co-culture that better mimics the in vivo vascular microenvironment. A double-flow bioreactor supported cellular interactions and reproduced the blood flow dynamic. VSMC calcification was stimulated with a DMEM high glucose calcification medium supplemented with 1.9 mM NaH2PO4/Na2HPO4 (1:1) for 7 days. Calcification, cell viability, inflammatory mediators, and molecular markers (SIRT-1, TGFβ1) related to VSMC differentiation were evaluated. Our dynamic model was able to reproduce VSMC calcification and inflammation and evidenced differences in the modulation of effectors involved in the VSMC calcified phenotype compared with standard monocultures, highlighting the importance of the microenvironment in controlling cell behavior. Hence, our platform represents an advanced system to investigate the pathophysiologic mechanisms underlying VC, providing information not available with the standard cell monoculture.