Recent evidence indicates synaptic dysfunction as an early mechanism affected in neuroinflammatory diseases, such as multiple sclerosis, which are characterized by chronic microglia activation. ...However, the mode(s) of action of reactive microglia in causing synaptic defects are not fully understood. In this study, we show that inflammatory microglia produce extracellular vesicles (EVs) which are enriched in a set of miRNAs that regulate the expression of key synaptic proteins. Among them, miR-146a-5p, a microglia-specific miRNA not present in hippocampal neurons, controls the expression of presynaptic synaptotagmin1 (Syt1) and postsynaptic neuroligin1 (Nlg1), an adhesion protein which play a crucial role in dendritic spine formation and synaptic stability. Using a
Renilla
-based sensor, we provide formal proof that inflammatory EVs transfer their miR-146a-5p cargo to neuron. By western blot and immunofluorescence analysis we show that vesicular miR-146a-5p suppresses Syt1 and Nlg1 expression in receiving neurons. Microglia-to-neuron miR-146a-5p transfer and Syt1 and Nlg1 downregulation do not occur when EV–neuron contact is inhibited by cloaking vesicular phosphatidylserine residues and when neurons are exposed to EVs either depleted of miR-146a-5p, produced by pro-regenerative microglia, or storing inactive miR-146a-5p, produced by cells transfected with an anti-miR-146a-5p. Morphological analysis reveals that prolonged exposure to inflammatory EVs leads to significant decrease in dendritic spine density in hippocampal neurons in vivo and in primary culture, which is rescued in vitro by transfection of a miR-insensitive Nlg1 form. Dendritic spine loss is accompanied by a decrease in the density and strength of excitatory synapses, as indicated by reduced mEPSC frequency and amplitude. These findings link inflammatory microglia and enhanced EV production to loss of excitatory synapses, uncovering a previously unrecognized role for microglia-enriched miRNAs, released in association to EVs, in silencing of key synaptic genes.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Microvesicles (MVs) released into the brain microenvironment are emerging as a novel way of cell‐to‐cell communication. We have recently shown that microglia, the immune cells of the brain, shed MVs ...upon activation but their possible role in microglia‐to‐neuron communication has never been explored. To investigate whether MVs affect neurotransmission, we analysed spontaneous release of glutamate in neurons exposed to MVs and found a dose‐dependent increase in miniature excitatory postsynaptic current (mEPSC) frequency without changes in mEPSC amplitude. Paired‐pulse recording analysis of evoked neurotransmission showed that MVs mainly act at the presynaptic site, by increasing release probability. In line with the enhancement of excitatory transmission in vitro, injection of MVs into the rat visual cortex caused an acute increase in the amplitude of field potentials evoked by visual stimuli. Stimulation of synaptic activity occurred via enhanced sphingolipid metabolism. Indeed, MVs promoted ceramide and sphingosine production in neurons, while the increase of excitatory transmission induced by MVs was prevented by pharmacological or genetic inhibition of sphingosine synthesis. These data identify microglia‐derived MVs as a new mechanism by which microglia influence synaptic activity and highlight the involvement of neuronal sphingosine in this microglia‐to‐neuron signalling pathway.
Microvesicles (MVs) shed from microglia stimulate neuronal exocytosis and enhance neurotransmission by inducing sphingolipid metabolism in neurons.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Objective:
Microvesicles (MVs) have been indicated as important mediators of intercellular communication and are emerging as new biomarkers of tissue damage. Our previous data indicate that reactive ...microglia/macrophages release MVs in vitro. The aim of the study was to evaluate whether MVs are released by microglia/macrophages in vivo and whether their number varies in brain inflammatory conditions, such as multiple sclerosis (MS).
Methods:
Electron and fluorescence microscopy and flow cytometry were used to detect myeloid MVs in the cerebrospinal fluid (CSF) of healthy controls, MS patients, and rodents affected by experimental autoimmune encephalomyelitis (EAE), the animal model of MS.
Results:
Myeloid MVs were detected in CSF of healthy controls. In relapsing and remitting EAE mice, the concentration of myeloid MVs in the CSF was significantly increased and closely associated with disease course. Analysis of MVs in the CSF of 28 relapsing patients and 28 patients with clinical isolated syndrome from 2 independent cohorts revealed higher levels of myeloid MVs than in 13 age‐matched controls, indicating a clinical value of MVs as a companion tool to capture disease activity. Myeloid MVs were found to spread inflammatory signals both in vitro and in vivo at the site of administration; mice impaired in MV shedding were protected from EAE, suggesting a pathogenic role for MVs in the disease. Finally, FTY720, the first approved oral MS drug, significantly reduced the amount of MVs in the CSF of EAE‐treated mice.
Interpretation:
These findings identify myeloid MVs as a marker and therapeutic target of brain inflammation. ANN NEUROL 2012;72:610–624
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Microglia/macrophages (M) are major contributors to postinjury inflammation, but they may also promote brain repair in response to specific environmental signals that drive classic (M1) or ...alternative (M2) polarization. We investigated the activation and functional changes of M in mice with traumatic brain injuries and receiving intracerebroventricular human bone marrow mesenchymal stromal cells (MSCs) or saline infusion. MSCs upregulated
Ym1
and
Arginase-1
mRNA (
p
< 0.001), two M2 markers of protective M polarization, at 3 and 7 d postinjury, and increased the number of Ym1
+
cells at 7 d postinjury (
p
< 0.05). MSCs reduced the presence of the lysosomal activity marker CD68 on the membrane surface of CD11b-positive M (
p
< 0.05), indicating reduced phagocytosis. MSC-mediated induction of the M2 phenotype in M was associated with early and persistent recovery of neurological functions evaluated up to 35 days postinjury (
p
< 0.01) and reparative changes of the lesioned microenvironment.
In vitro
, MSCs directly counteracted the proinflammatory response of primary murine microglia stimulated by tumor necrosis factor-α + interleukin 17 or by tumor necrosis factor-α + interferon-γ and induced M2 proregenerative traits, as indicated by the downregulation of inducible nitric oxide synthase and upregulation of
Ym1
and
CD206
mRNA (
p
< 0.01). In conclusion, we found evidence that MSCs can drive the M transcriptional environment and induce the acquisition of an early, persistent M2-beneficial phenotype both
in vivo
and
in vitro
. Increased Ym1 expression together with reduced
in vivo
phagocytosis suggests M selection by MSCs towards the M2a subpopulation, which is involved in growth stimulation and tissue repair.
Training in medical ethics aims to educate health care professionals in dealing with daily care ethical issues. To guarantee quality of life and spiritual and emotional support, palliative care ...professionals have to develop ethical and relational skills. We propose the implementation and evaluation of a specialized training programme in medical ethics dedicated to a hospital-based Palliative Care Unit.
This study is a mixed-method before-after evaluation with data triangulation.
The results highlight that participants developed their ethical knowledge, and a deeper ethical awareness. They also felt more confident and motivated to widely apply ethical reflections and reasonings in their daily practice.
The participants appreciated the innovative structure of the training, especially regarding the integration of the theoretical-interactive and practical parts. However, they recommended increasing the number of concrete occasions for ethical supervision and practical application of what they learned during the programme. The training programme also has some potential practical implications: the development of advanced ethical skills within a hospital-based PC team may improve the quality of life of the patients and their families. In addition, health care professionals with advanced ethical competencies are able to educate patients and their families towards more active participation in the decision-making process.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This study aims to quantitatively and qualitatively evaluate the activities of a Bioethics Unit (BU) 5 years since its implementation (2016-2020). The BU is a research unit providing empirical ...research on ethical issues related to clinical practice, clinical ethics consultation, and ethical education for health care professionals (HPS).
We performed an explanatory, sequential, mixed-method, observational study, using the subsequent qualitative data to explain the initial quantitative findings. Quantitative data were collected from an internal database and analyzed by descriptive analysis. Qualitative evaluation was performed by semi-structured interviews with 18 HPs who were differently involved in the BU's activities and analyzed by framework analysis.
Quantitative results showed an extensive increment of the number of BU research projects over the years and the number of work collaborations with other units and wards. Qualitative findings revealed four main themes, concerning: 1. the reasons for contacting the BU and the type of collaboration; 2. the role of the bioethicist; 3. the impact of BU activities on HPs, in terms of developing deeper and more mature thinking; 4. the need to extend ethics support to other settings. Overall, our results showed that performing both empirical bioethics research and more traditional clinical ethics activities at the same unit would produce an impetus to increase collaboration and spread an 'ethical culture' among local HPs.
Our findings contribute to a growing body of literature on the models of clinical ethics support services and the role of empirical research in bioethics internationally. They also prepare the ground for the implementation of a multidisciplinary Clinical Ethics Committee (CEC) that aims to support the BU's ethics consultation service within the local context.
Chronic hepatitis C is the main cause of death in patients with end-stage liver disease. Prognosis depends on the increase of fibrosis, whose progression is twice as rapid in men as in women. Aim of ...the study was to evaluate the effects of reproductive stage on fibrosis severity in women and to compare these findings with age-matched men.
A retrospective study of 710 consecutive patients with biopsy-proven chronic hepatitis C was conducted, using data from a clinical database of two tertiary Italian care centers. Four age-matched groups of men served as controls. Data about demographics, biochemistry, liver biopsy and ultrasonography were analyzed. Contributing factors were assessed by multivariate logistic regression analysis.
Liver fibrosis was more advanced in the early menopausal than in the fully reproductive (P<0.0001) or premenopausal (P = 0.042) group. Late menopausal women had higher liver fibrosis compared with the other groups (fully reproductive, P<0.0001; premenopausal, P = <0.0001; early menopausal, P = 0.052). Multivariate analyses showed that male sex was independently associated with more severe fibrosis in the groups corresponding to premenopausal (P = 0.048) and early menopausal (P = 0.004) but not late menopausal pairs. In women, estradiol/testosterone ratio decreased markedly in early (vs. reproductive age: P = 0.002 and vs. premenopausal: P<0.0001) and late menopause (vs. reproductive age: P = 0.001; vs. premenopausal: P<0.0001). In men age-matched with menopausal women, estradiol/testosterone ratio instead increased (reproductive age group vs. early: P = 0.002 and vs. late M: P = 0.001).
The severity of fibrosis in women worsens in parallel with increasing estrogen deprivation and estradiol/testosterone ratio decrease. Our data provide evidence why fibrosis progression is discontinuous in women and more linear and severe in men, in whom aging-associated estradiol/testosterone ratio increase occurs too late to noticeably influence the inflammatory process leading to fibrosis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Patients with advanced haematological malignancies suffer from a very high symptom burden and psychological, spiritual, social and physical symptoms comparable with patients with metastatic ...non-haematological malignancy. Referral to palliative care services for these patients remains limited or often confined to the last days of life. We developed a palliative care intervention (PCI) integrated with standard haematological care. The aim of the study was focussed on exploring the feasibility of the intervention by patients, professionals and caregivers and on assessing its preliminary efficacy.
This is a mixed-methods phase 2 trial. The Specialist Palliative Care Team (SPCT) will follow each patient on a monthly basis in the outpatient clinic or will provide consultations during any hospital admission. SPCT and haematologists will discuss active patient issues to assure a team approach to the patient's care. This quantitative study is a monocentric parallel-group superiority trial with balanced randomisation comparing the experimental PCI plus haematological standard care versus haematological standard care alone. The primary endpoint will calculate on adherence to the planned PCI, measured as the percentage of patients randomised to the experimental arm who attend all the planned palliative care visits in the 24 weeks after randomisation. The qualitative study follows the methodological indications of concurrent nested design and was aimed at exploring the acceptability of the PCI from the point of view of patients, caregivers and physicians.
In this trial, we will test the feasibility of an integrated palliative care approach starting when the haematologist decides to propose the last active treatment to the patient, according to his/her clinical judgement. We decided to test this criterion because it is able to intercept a wide range of patients'needs. The feasibility of this approach requires that we enrol at least 60 patients and that more than 50% of them be followed by the palliative care team for at least 24 weeks. The trial will include integrated qualitative data analysis; to give essential information on feasibility and acceptability.
ClinicalTrials.gov: NCT03743480 (November 16, 2018).
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Obesity is becoming a silent worldwide epidemic, with a steady increase in both adults and children. To date, even though several drugs have been licensed for long‐term obesity treatment, none of ...them are yet used in routine clinical practice. So far the only successful intervention has been behavioral therapy. A suitable and economic experimental model mimicking the human condition would therefore be extremely useful to evaluate preventive measures and novel treatments. Zebrafish are emerging as an important model system to study obesity and related metabolic disease. Remarkable similarities have been reported in lipid metabolism and the adipogenic pathway between zebrafish and mammals. Moreover, the zebrafish possesses a number of features—the relative inexpensiveness of animal husbandry, its optical transparency and the ability to produce a large number of offspring at low cost—that make it ideal for large‐scale screening and for testing drugs and intervention. In this review, we summarize recent progress in using zebrafish as a model system to study obesity and obesity‐related metabolic disorders. We describe several zebrafish models (in both larvae and adult animals) that develop obesity and non‐alcoholic fatty liver disease (NAFLD) using different approaches, including gene manipulation, diet manipulation and modification of microbiota composition. For these models, we have outlined the specific aspects related to obesity and its development and we have summarized their advantages and limitations.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
Background
Dignity is a basic principle of palliative care and is intrinsic in the daily practice of professionals assisting individuals with incurable diseases. Dignity Therapy (DT) is a ...short-term intervention aimed at improving the sense of purpose, meaning and self-worth and at reducing the existential distress of patients facing advanced illness. Few studies have examined how DT works in countries of non-Anglo Saxon culture and in different real-life settings. Moreover, most studies do not provide detailed information on how DT is conducted, limiting a reliable assessment of DT protocol application and of its evaluation procedure.
The aim of this study was to assess the feasibility and acceptability of a nurse-led DT intervention in advanced cancer patients receiving palliative care.
Method
This is a mixed-method study using before and after evaluation and semistructured interviews. Cancer patients referred to a hospital palliative care unit were recruited and provided with DT. The duration of sessions, and timeframes concerning each step of the study, were recorded, and descriptive statistical analyses were performed.
The patients' dignity-related distress and feedback toward the intervention were assessed through the Patient Dignity Inventory and the Dignity Therapy Patient Feedback Questionnaire, respectively. Three nurses were interviewed on their experience in delivering the intervention, and the data were analyzed qualitatively.
Results
A total of 37/50 patients were enrolled (74.0%), of whom 28 (75.7%) completed the assessment. In 76.7% of cases, patients completed the intervention in the time limit scheduled in the study. No statistically significant reduction in the Patient Dignity Inventory scores was observed at the end of the intervention; most patients found DT to be helpful and satisfactory. Building opportunities for personal growth and providing holistic care emerged among the facilitators to DT implementation. Nurses also highlighted too great of a time commitment and a difficult collaboration with ward colleagues among the barriers.
Conclusions
Our findings strongly support the acceptability, but only partially support the feasibility, of nurse-led DT in advanced cancer patients in a hospital setting. Further research is needed on how to transfer the potential benefits of DT into clinical practice.
Trial registration
Retrospectively registered on ClinicalTrial.gov
NCT04738305
.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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