The Place of Language. Essays in Honor of Giuliana Garzone

Introductio

Neuronal haemoglobin induces loss of dopaminergic neurons in mouse Substantia nigra, cognitive deficits and cleavage of endogenous α-synuclein

Parkinson's disease (PD) presents the selective loss of A9 dopaminergic (DA) neurons of Substantia Nigra pars compacta (SNpc) and the presence of intracellular aggregates called Lewy bodies. alpha-synuclein (alpha-syn) species truncated at the carboxy-terminal (C-terminal) accumulate in pathological inclusions and promote alpha-syn aggregation and toxicity. Haemoglobin (Hb) is the major oxygen carrier protein in erythrocytes. In addition, Hb is expressed in A9 DA neurons where it influences mitochondrial activity. Hb overexpression increases cells' vulnerability in a neurochemical model of PD in vitro and forms cytoplasmic and nucleolar aggregates upon short-term overexpression in mouse SNpc. In this study, alpha and beta-globin chains were co-expressed in DA cells of SNpc in vivo upon stereotaxic injections of an Adeno-Associated Virus isotype 9 (AAV9) and in DA iMN9D cells in vitro. Long-term Hb over-expression in SNpc induced the loss of about 50% of DA neurons, mild motor impairments, and deficits in recognition and spatial working memory. Hb triggered the formation of endogenous alpha-syn C-terminal truncated species. Similar alpha-syn fragments were found in vitro in DA iMN9D cells over-expressing alpha and beta- globins when treated with pre-formed alpha-syn fibrils. Our study positions Hb as a relevant player in PD pathogenesis for its ability to trigger DA cells' loss in vivo and the formation of C-terminal alpha-syn fragments

SINEUP non-coding RNAs rescue defective frataxin expression and activity in a cellular model of Friedreich's Ataxia

Friedreich's ataxia (FRDA) is an untreatable disorder with neuro- and cardio-degenerative progression. This monogenic disease is caused by the hyper-expansion of naturally occurring GAA repeats in the first intron of the FXN gene, encoding for frataxin, a protein implicated in the biogenesis of iron-sulfur clusters. As the genetic defect interferes with FXN transcription, FRDA patients express a normal frataxin protein but at insufficient levels. Thus, current therapeutic strategies are mostly aimed to restore physiological FXN expression. We have previously described SINEUPs, natural and synthetic antisense long non-coding RNAs, which promote translation of partially overlapping mRNAs through the activity of an embedded SINEB2 domain. Here, by in vitro screening, we have identified a number of SINEUPs targeting human FXN mRNA and capable to up-regulate frataxin protein to physiological amounts acting at the post-transcriptional level. Furthermore, FXN-specific SINEUPs promote the recovery of disease-associated mitochondrial aconitase defects in FRDA-derived cells. In summary, we provide evidence that SINEUPs may be the first gene-specific therapeutic approach to activate FXN translation in FRDA and, more broadly, a novel scalable platform to develop new RNA-based therapies for haploinsufficient diseases

Neuronal hemoglobin: new insights into the mechanism of \u237a-synuclein pathogenicity

\u3b1-synucleinopathies are a subset of progressive neurodegenerative disorders that share several features and, above all, \u3b1-synuclein (\u3b1-syn) accumulation. Lewy bodies and neurites are typical of Parkinson\u2019s disease (PD) and dementia with Lewy bodies, while Multiple System Atrophy is characterized by the presence of glial cytoplasmic inclusions. Several mechanisms are involved in the pathogenesis of these diseases, ranging from genetic factors, environment, cellular disfunctions to \u3b1-syn misfolding. An increasing number of studies reported that \u3b1-syn is subjected to post-translational modifications within Lewy bodies. Among them, C-terminal truncation seems to increase its aggregation propensity. Hemoglobin (Hb) genes expression was recently demonstrated in the central nervous system and evidences suggest a putative role as oxygen reservoir and in mitochondrial respiration. Dysregulation of Hb expression has been associated to several neurodegenerative disorders and, in particular, to PD. Previous data from the laboratory of Prof. Gustincich showed that Hb alters mitochondrial genes expression1, confers dopaminergic (DA) cells\u2019 susceptibility to MPP+ and rotenone in vitro and impairs performance associated to motor learning in vivo2. Interestingly, the presence of Hb - \u3b1-syn complexes in the brain of aging cynomolgus monkeys has recently been demonstrated3. In this study, we aimed to unveil the interplay between Hb and \u3b1-syn and its contribution to synucleinopathies. To this purpose, we took advantage of MN9D-Nurr1Tet-On dopaminergic neuroblastoma cell lines (iMN9D) stably transfected with \u3b1 and \u3b2 chains of Hb1 and \u3b1-syn preformed fibrils (PFFs) as a model of \u3b1-syn pathogenicity. We first demonstrate that iMN9D cells internalize PFFs and are therefore a suitable system to study \u3b1-syn pathogenicity. Then, we show that PFFs treatment is toxic to cells and leads to the accumulation of \u3b1-syn C-terminal truncated species (DC-\u3b1-syn) triggered in the presence of Hb. Given the relevance of C-terminal cleavage products in terms of \u3b1-syn aggregation and toxicity, we investigate the intracellular proteases likely involved in \u3b1-syn truncation. Among them, we provide evidence that, in our model, calpains are involved in \u3b1-syn truncation. In conclusion, taken together, these findings strongly support Hb implication in \u3b1-syn processing and, therefore it exerts a significant role in the pathogenesis of \u3b1-synucleinopathies

The place of language: discourse, translation, culture

This special issue celebrates the outstanding career of Giuliana Garzone, whose scientific endeavors covered all the domains outlined in the title of this issue, with significant forays also in the field of literature

Aggreement in Argumentation. A discursive perspective

This book explores the construction of agreement in the argumentative process, aiming to investigate how the activation of shared knowledge, values and beliefs leads to the creation of a common ground between the speaker and the audience in the pursuit of persuasion. In the first part of the book, the authors examine agreement from a historical and theoretical perspective, setting in relation major ancient and contemporary approaches to argumentation, with special regard for the notions of ethos, objects of agreement, starting points and topoi, all with a focus on their deployment in discourse. This is complemented with a compendium of linguistic resources that can be exploited for the discursive construction of agreement, offering a principled selection of structures across different levels of language description. The second part of the book is devoted to the investigation of actual uses of agreement in a choice of institutional genres within the domain of the US presidential elections: the Presidential Announcement, the TV debate and the Inaugural Address. Due to their political relevance and cultural salience, these genres provide an ideal interface for observing the interplay of discursive and argumentative components, against the backdrop of a shared cultural heritage, rich with intertextual references. The application of the theoretical framework developed in the first part of the book to the analysis of real political discourse carried out in the second is the distinguishing feature of this volume, making it of interest to linguists and argumentation scholars, as well as to political scientists and communicators