Role of mesenchymal stromal cell-derived extracellular vesicles in tumour microenvironment

Abstract Stromal cells, deriving from mesenchymal stromal cells (MSCs), are crucial component of tumour microenvironment and represent key regulators of tumour processes. MSCs can be recruited to the tumour environment and interact with many cellular elements, thus influencing tumour biology. Cell-to-cell communication is in part mediated by the release of extracellular vesicle (EVs). EVs can induce significant molecular changes in recipient cells, delivering bioactive molecules. In this review, we describe the MSC-derived EVs content and discuss their role in different processes related to cancer biology. Furthermore, we summarize chemical or biological EVs modifications aiming to develop more efficient antitumor therapies

Attention deficits after incident stroke in the acute period: Frequency across types of attention and relationships to patient characteristics and functional outcomes

Background: Attention deficits are common post stroke and result in poorer functional outcomes. This study examined the frequency of attention deficits after incident stroke and their correlates. Method: Attention of 94 stroke survivors was assessed using the Bells test, Trails Making Test A/B, 2.4- and 2.0-second trials of the Paced Auditory Serial Addition Test (PASAT), and Integrated Auditory Visual Continuous Performance Test (IVA-CPT) within 3 weeks post stroke. Wider functioning was assessed using the Medical Short Form-36 (SF-36) Physical and Mental Component Summary scores (PCS and MCS), London Handicap Scale, Modified Rankin Scale, General Health Questionnaire-28, and Cognitive Failures Questionnaire (CFQ). Results: Most participants were impaired or very impaired on the IVA-CPT (z scores > 3 SDs below normative mean) but not other attention measures. Functional independence and cognitive screening test (Mini-Mental State Examination) performance were significantly related to IVA-CPT, Trails A/B, and Bells tests but not PASAT. Better performance across the Bells test was related to better SF-36 PCS, whereas Trails A and the PASAT were related to SF-36 MCS. Better CFQ naming was related to Trails B, whereas worse CFQ memory was related to better PASAT performance. Conclusion: Attention deficits are common post stroke, though frequency varies widely across the forms of attention assessed, with tests of neglect and speeded attention tasks being linked to quality of life. This variability of performance and linking to wider outcomes suggests the need for comprehensive assessment of attention and that attention is a viable target for rehabilitative efforts

Gender specific medicine in liver diseases: a point of view.

Gender medicine focuses on the patho-physiological, clinical, prevention and treatment differences in diseases that are equally represented in men and women. The purpose of gender medicine is to ensure that each individual man and woman receives the best treatment possible based on scientific evidence. The concept of “gender” includes not only the sexual characteristics of individuals but also physiological and psychological attributes of men and women, including risk factors, protective/aggravating effects of sexual hormones and variances linked to genetics and corporal structures that explain biological and physiological differences between men and women. It is very important to consider all the biological, physiological, functional, psychological, social and cultural characteristics to provide patients with individualized disease management. Herein, we critically analyze the literature regarding gender differences for diseases and acquired conditions of the most representative hepatic pathologies: primary biliary cirrhosis, autoimmune hepatitis, primary sclerosing cholangitis, non alcoholic fatty liver disease and alcoholic liver disease, and viral chronic hepatitis B and C. The last section addresses hemochromatosis, which is a prevalent iron overload disorder in the Caucasian population. This review aims to describe data from the literature concerning viral chronic hepatitis during pregnancy, management during pregnancy and delivery, and new effective drugs for the prevention of maternal infection transmission without significant adverse effects or complications

Redistribution of DAT/α-synuclein complexes visualized by “in situ” proximity ligation assay in transgenic mice modelling early Parkinson’s disease

Alpha-synuclein, the major component of Lewy bodies, is thought to play a central role in the onset of synaptic dysfunctions in Parkinson's disease (PD). In particular, α-synuclein may affect dopaminergic neuron function as it interacts with a key protein modulating dopamine (DA) content at the synapse: the DA transporter (DAT). Indeed, recent evidence from our "in vitro" studies showed that α-synuclein aggregation decreases the expression and membrane trafficking of the DAT as the DAT is retained into α-synuclein-immunopositive inclusions. This notwithstanding, "in vivo" studies on PD animal models investigating whether DAT distribution is altered by the pathological overexpression and aggregation of α-synuclein are missing. By using the proximity ligation assay, a technique which allows the "in situ" visualization of protein-protein interactions, we studied the occurrence of alterations in the distribution of DAT/α-synuclein complexes in the SYN120 transgenic mouse model, showing insoluble α-synuclein aggregates into dopaminergic neurons of the nigrostriatal system, reduced striatal DA levels and an altered distribution of synaptic proteins in the striatum. We found that DAT/α-synuclein complexes were markedly redistributed in the striatum and substantia nigra of SYN120 mice. These alterations were accompanied by a significant increase of DAT striatal levels in transgenic animals when compared to wild type littermates. Our data indicate that, in the early pathogenesis of PD, α-synuclein acts as a fine modulator of the dopaminergic synapse by regulating the subcellular distribution of key proteins such as the DAT

Ketamine enhances structural plasticity in mouse mesencephalic and human iPSC-derived dopaminergic neurons via AMPAR-driven BDNF and mTOR signaling

Among neurobiological mechanisms underlying antidepressant properties of ketamine, structural remodeling of prefrontal and hippocampal neurons has been proposed as critical. The suggested mechanism involves downstream activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, which trigger mammalian target of rapamycin (mTOR)-dependent structural plasticity via brain-derived neurotrophic factor (BDNF) and protein neo-synthesis. We evaluated whether ketamine elicits similar molecular events in dopaminergic (DA) neurons, known to be affected in mood disorders, using a novel, translational strategy that involved mouse mesencephalic and human induced pluripotent stem cells-derived DA neurons. Sixty minutes exposure to ketamine elicited concentration-dependent increases of dendritic arborization and soma size in both mouse and human cultures as measured 72 hours after application. These structural effects were blocked by mTOR complex/signaling inhibitors like rapamycin. Direct evidence of mTOR activation by ketamine was revealed by its induction of p70S6 kinase. All effects of ketamine were abolished by AMPA receptor antagonists and mimicked by the AMPA-positive allosteric modulator CX614. Inhibition of BDNF signaling prevented induction of structural plasticity by ketamine or CX614. Furthermore, the actions of ketamine required functionally intact dopamine D3 receptors (D3R), as its effects were abolished by selective D3R antagonists and absent in D3R knockout preparations. Finally, the ketamine metabolite (2R,6R)-hydroxynorketamine mimicked ketamine effects at sub-micromolar concentrations. These data indicate that ketamine elicits structural plasticity by recruitment of AMPAR, mTOR and BDNF signaling in both mouse mesencephalic and human induced pluripotent stem cells-derived DA neurons. These observations are of likely relevance to the influence of ketamine upon mood and its other functional actions in vivo.Molecular Psychiatry advance online publication, 21 November 2017; doi:10.1038/mp.2017.241

Cognitive impairment after lacunar stroke: systematic review and meta-analysis of incidence, prevalence and comparison with other stroke subtypes

Funding SDJM is supported by a Wellcome Trust Project Grant (WT088134/Z/09/A). JMW is supported by the Scottish Funding Council through the Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Initiative (http://www. sinapse.ac.uk). The study was independent of the funders.Peer reviewedPublisher PD