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1.
Ann Neurol ; 93(1): 196-204, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36218142

RESUMO

OBJECTIVE: The objective of this study was to outline the dynamics of prokineticin-2 pathway in relation to clinical-pathological features of Parkinson's disease by examining olfactory neurons of patients. METHODS: Thirty-eight patients (26 de novo, newly diagnosed) and 31 sex/age-matched healthy controls underwent noninvasive mucosa brushing for olfactory neurons collection, and standard clinical assessment. Gene expression levels of prokineticin-2, prokineticin-2 receptors type 1 and 2, and prokineticin-2-long peptide were measured in olfactory neurons by real-time polymerase chain reaction (PCR); moreover, the prokineticin-2 protein and α-synuclein species (total and oligomeric) were quantified by immunofluorescence staining. RESULTS: Prokineticin-2 expression was significantly increased in Parkinson's disease. De novo patients had higher prokineticin-2 levels, directly correlated with Movement Disorder Society-Sponsored Revision of the Unified Parkinson Disease Rating Scale (MDS-UPDRS) part III motor score. In addition, oligomeric α-synuclein was higher in Parkinson's disease and directly correlated with prokineticin-2 protein levels. Total α-synuclein did not differ between patients and controls. INTERPRETATION: Prokineticin-2 is a chemokine showing neuroprotective effects in experimental models of Parkinson's disease, but translational proof of its role in patients is still lacking. Here, we used olfactory neurons as the ideal tissue to analyze molecular stages of neurodegeneration in vivo, providing unprecedented evidence that the prokineticin-2 pathway is activated in patients with Parkinson's disease. Specifically, prokineticin-2 expression in olfactory neurons was higher at early disease stages, proportional to motor severity, and associated with oligomeric α-synuclein accumulation. These data, consistently with preclinical findings, support prokineticin-2 as a candidate target in Parkinson's disease, and validate reliability of olfactory neurons to reflect pathological changes of the disease. ANN NEUROL 2023;93:196-204.


Assuntos
Doença de Parkinson , Humanos , alfa-Sinucleína/genética , Testes de Estado Mental e Demência , Neurônios/metabolismo , Doença de Parkinson/genética , Reprodutibilidade dos Testes
2.
J Am Soc Nephrol ; 33(4): 810-827, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35273087

RESUMO

INTRODUCTION: CKD is associated with alterations of tubular function. Renal gluconeogenesis is responsible for 40% of systemic gluconeogenesis during fasting, but how and why CKD affects this process and the repercussions of such regulation are unknown. METHODS: We used data on the renal gluconeogenic pathway from more than 200 renal biopsies performed on CKD patients and from 43 kidney allograft patients, and studied three mouse models, of proteinuric CKD (POD-ATTAC), of ischemic CKD, and of unilateral urinary tract obstruction. We analyzed a cohort of patients who benefitted from renal catheterization and a retrospective cohort of patients hospitalized in the intensive care unit. RESULTS: Renal biopsies of CKD and kidney allograft patients revealed a stage-dependent decrease in the renal gluconeogenic pathway. Two animal models of CKD and one model of kidney fibrosis confirm gluconeogenic downregulation in injured proximal tubule cells. This shift resulted in an alteration of renal glucose production and lactate clearance during an exogenous lactate load. The isolated perfused kidney technique in animal models and renal venous catheterization in CKD patients confirmed decreased renal glucose production and lactate clearance. In CKD patients hospitalized in the intensive care unit, systemic alterations of glucose and lactate levels were more prevalent and associated with increased mortality and a worse renal prognosis at follow-up. Decreased expression of the gluconeogenesis pathway and its regulators predicted faster histologic progression of kidney disease in kidney allograft biopsies. CONCLUSION: Renal gluconeogenic function is impaired in CKD. Altered renal gluconeogenesis leads to systemic metabolic changes with a decrease in glucose and increase in lactate level, and is associated with a worse renal prognosis.


Assuntos
Gluconeogênese , Insuficiência Renal Crônica , Animais , Gluconeogênese/fisiologia , Humanos , Rim/metabolismo , Túbulos Renais Proximais/metabolismo , Camundongos , Insuficiência Renal Crônica/metabolismo , Estudos Retrospectivos
3.
Int J Mol Sci ; 23(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36142305

RESUMO

Whole body vibration (WBV) is well known to exert beneficial effects on multiple tissues, improving synaptic transmission, muscle mass, bone quality, and reducing anxiety and depressive behavior. However, the underlying molecular mechanisms are not yet fully understood, and organs and tissues may respond differently to the vibratory stimulus depending on multiple factors. Therefore, we investigated the WBV effects on the brain and musculoskeletal tissue of 4-month-old young mice, evaluating synaptic plasticity by electrophysiological recordings and tissue organization by histology and histomorphometric analysis. Specifically, WBV protocols were characterized by the same vibration frequency (45 Hz), but different in vibration exposure time (five series of 3 min for the B protocol and three series of 2 min and 30 s for the C protocol) and recovery time between two vibration sessions (1 min for the B protocol and 2 min and 30 s for the C protocol). In addition, immunohistochemistry was conducted to evaluate the expression of fibronectin type III domain-containing protein 5 (FNDC5), as well as that of tissue-specific markers, such as brain-derived neurotrophic factor (BDNF) in brain, myostatin in muscle and collagen I (COL-1) in bone. Our results suggest that the WBV effects depend closely on the type of protocol used and support the hypothesis that different organs or tissues have different susceptibility to vibration. Further studies will be needed to deepen our knowledge of physiological adaptations to vibration and develop customized WBV protocols to improve and preserve cognitive and motor functions.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Vibração , Adaptação Fisiológica , Animais , Encéfalo , Colágeno , Fibronectinas , Camundongos , Miostatina , Vibração/uso terapêutico
4.
Int J Mol Sci ; 22(8)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920464

RESUMO

Salmon calcitonin is a good model for studying amyloid behavior and neurotoxicity. Its slow aggregation rate allows the purification of low molecular weight prefibrillar oligomers, which are the most toxic species. It has been proposed that these species may cause amyloid pore formation in neuronal membranes through contact with negatively charged sialic acid residues of the ganglioside GM1. In particular, it has been proposed that an electrostatic interaction may be responsible for the initial contact between prefibrillar oligomers and GM1 contained in lipid rafts. Based on this evidence, the aim of our work was to investigate whether the neurotoxic action induced by calcitonin prefibrillar oligomers could be counteracted by treatment with neuraminidase, an enzyme that removes sialic acid residues from gangliosides. Therefore, we studied cell viability in HT22 cell lines and evaluated the effects on synaptic transmission and long-term potentiation by in vitro extracellular recordings in mouse hippocampal slices. Our results showed that treatment with neuraminidase alters the surface charges of lipid rafts, preventing interaction between the calcitonin prefibrillar oligomers and GM1, and suggesting that the enzyme, depending on the concentration used, may have a partial or total protective action in terms of cell survival and modulation of synaptic transmission.


Assuntos
Neuropatias Amiloides , Calcitonina/toxicidade , Proteínas de Peixes/toxicidade , Neuraminidase/farmacologia , Salmão , Neuropatias Amiloides/induzido quimicamente , Neuropatias Amiloides/metabolismo , Neuropatias Amiloides/patologia , Neuropatias Amiloides/prevenção & controle , Animais , Gangliosídeo G(M1)/metabolismo , Masculino , Microdomínios da Membrana/metabolismo , Microdomínios da Membrana/patologia , Camundongos , Camundongos Endogâmicos BALB C , Eletricidade Estática
6.
Blood ; 129(11): e26-e37, 2017 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-28122742

RESUMO

Drug sensitivity and resistance testing on diagnostic leukemia samples should provide important functional information to guide actionable target and biomarker discovery. We provide proof of concept data by profiling 60 drugs on 68 acute lymphoblastic leukemia (ALL) samples mostly from resistant disease in cocultures of bone marrow stromal cells. Patient-derived xenografts retained the original pattern of mutations found in the matched patient material. Stromal coculture did not prevent leukemia cell cycle activity, but a specific sensitivity profile to cell cycle-related drugs identified samples with higher cell proliferation both in vitro and in vivo as leukemia xenografts. In patients with refractory relapses, individual patterns of marked drug resistance and exceptional responses to new agents of immediate clinical relevance were detected. The BCL2-inhibitor venetoclax was highly active below 10 nM in B-cell precursor ALL (BCP-ALL) subsets, including MLL-AF4 and TCF3-HLF ALL, and in some T-cell ALLs (T-ALLs), predicting in vivo activity as a single agent and in combination with dexamethasone and vincristine. Unexpected sensitivity to dasatinib with half maximal inhibitory concentration values below 20 nM was detected in 2 independent T-ALL cohorts, which correlated with similar cytotoxic activity of the SRC inhibitor KX2-391 and inhibition of SRC phosphorylation. A patient with refractory T-ALL was treated with dasatinib on the basis of drug profiling information and achieved a 5-month remission. Thus, drug profiling captures disease-relevant features and unexpected sensitivity to relevant drugs, which warrants further exploration of this functional assay in the context of clinical trials to develop drug repurposing strategies for patients with urgent medical needs.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Células Cultivadas , Técnicas de Cocultura , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
7.
Zygote ; 25(2): 205-214, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28274294

RESUMO

Sea urchin represents an ideal model for studies on fertilization and early development, but the achievement of egg competence and mitochondrial behaviour during oogenesis remain to be enlightened. Oocytes of echinoid, such as sea urchin, unlike other echinoderms and other systems, complete meiotic maturation before fertilization. Mitochondria, the powerhouse of eukaryotic cells, contain a multi-copy of the maternally inherited genome, and are involved directly at several levels in the reproductive processes, as their functional status influences the quality of oocytes and contributes to fertilization and embryogenesis. In the present paper, we report our latest data on mitochondrial distribution, content and activity during Paracentrotus lividus oogenesis. The analyses were carried out using confocal microscopy, in vivo incubating oocytes at different maturation stages with specific probes for mitochondria and mtDNA, and by immunodetection of Hsp56, a well known mitochondrial marker. Results show a parallel rise of mitochondrial mass and activity, and, especially in the larger oocytes, close to germinal vesicle (GV) breakdown, a considerable increase in organelle activity around the GV, undoubtedly for an energetic aim. In the mature eggs, mitochondrial activity decreases, in agreement with their basal metabolism. Further and significant information was achieved by studying the mitochondrial chaperonin Hsp56 and mtDNA. Results show a high increase of both Hsp56 and mtDNA. Taken together these results demonstrate that during oogenesis a parallel rise of different mitochondrial parameters, such as mass, activity, Hsp56 and mtDNA occurs, highlighting important tools in the establishment of developmental competence.


Assuntos
Embrião não Mamífero/metabolismo , Mitocôndrias/metabolismo , Oócitos/metabolismo , Oogênese/fisiologia , Animais , DNA Mitocondrial/genética , Embrião não Mamífero/citologia , Feminino , Oócitos/citologia , Fosforilação Oxidativa , Ouriços-do-Mar , Proteínas de Ligação a Tacrolimo/metabolismo
8.
Transplantation ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502560

RESUMO

BACKGROUND: Taurine is one of the most abundant amino acids in humans. Low taurine levels are associated with cellular senescence, mitochondrial dysfunction, DNA damage, and inflammation in mouse, all of which can be reversed by supplementation. It is unknown whether taurine metabolism is associated with kidney allograft function and survival. METHODS: We performed urine metabolomic profiling of kidney transplant recipients in the early and late phases after transplantation combined with transcriptomic analysis of human kidney allografts. Single-nucleus RNA sequencing data sets of mouse kidneys after ischemia-reperfusion injury were analyzed. We analyzed the association of urinary taurine levels and taurine metabolism genes with kidney function, histology, and graft survival. RESULTS: Urine taurine concentrations were significantly lower in kidney transplant recipients who experienced delayed graft function. In a mouse model of ischemia-reperfusion injury, the taurine biosynthesis gene, CSAD, but not the taurine transporter SLC6A6, was repressed. In the late stage of transplantation, low level of taurine in urine was associated with impaired kidney function and chronic structural changes. Urine taurine level in the lowest tertile was predictive of graft loss. Expression of the taurine transporter SLC6A6 in the upper median, but not CSAD, was associated with chronic kidney injury and was predictive of graft loss. CONCLUSIONS: Low urine taurine level is a marker of injury in the kidney allograft, is associated with poor kidney function, is associated with chronic histological changes, and is predictive of graft survival. The differential expression of CSAD and SLC6A6, depending on the time after transplantation and marks of injury, highlights different mechanisms affecting taurine metabolism.

9.
PLoS One ; 19(3): e0300888, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512830

RESUMO

Neuronal death could be responsible for the cognitive impairments found in astronauts exposed to spaceflight, highlighting the need to identify potential countermeasures to ensure neuronal health in microgravity conditions. Therefore, differentiated HT22 cells were exposed to simulated microgravity by random positioning machine (RPM) for 48 h, treating them with a single administration of Trolox, recombinant irisin (r-Irisin) or both. Particularly, we investigated cell viability by MTS assay, Trypan Blue staining and western blotting analysis for Akt and B-cell lymphoma 2 (Bcl-2), the intracellular increase of reactive oxygen species (ROS) by fluorescent probe and NADPH oxidase 4 (NOX4) expression, as well as the expression of brain-derived neurotrophic factor (BDNF), a major neurotrophin responsible for neurogenesis and synaptic plasticity. Although both Trolox and r-Irisin manifested a protective effect on neuronal health, the combined treatment produced the best results, with significant improvement in all parameters examined. In conclusion, further studies are needed to evaluate the potential of such combination treatment in counteracting weightlessness-induced neuronal death, as well as to identify other potential strategies to safeguard the health of astronauts exposed to spaceflight.


Assuntos
Cromanos , Fibronectinas , Ausência de Peso , Fibronectinas/farmacologia , Fibronectinas/metabolismo , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Diferenciação Celular
10.
iScience ; 27(3): 109271, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38487013

RESUMO

The application of single-cell technologies in clinical nephrology remains elusive. We generated an atlas of transcriptionally defined cell types and cell states of human kidney disease by integrating single-cell signatures reported in the literature with newly generated signatures obtained from 5 patients with acute kidney injury. We used this information to develop kidney-specific cell-level information ExtractoR (K-CLIER), a transfer learning approach specifically tailored to evaluate the role of cell types/states on bulk RNAseq data. We validated the K-CLIER as a reliable computational framework to obtain a dimensionality reduction and to link clinical data with single-cell signatures. By applying K-CLIER on cohorts of patients with different kidney diseases, we identified the most relevant cell types associated with fibrosis and disease progression. This analysis highlighted the central role of altered proximal tubule cells in chronic kidney disease. Our study introduces a new strategy to exploit the power of single-cell technologies toward clinical applications.

11.
Science ; 383(6685): eadd6371, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386758

RESUMO

The steps governing healing with or without fibrosis within the same microenvironment are unclear. After acute kidney injury (AKI), injured proximal tubular epithelial cells activate SOX9 for self-restoration. Using a multimodal approach for a head-to-head comparison of injury-induced SOX9 lineages, we identified a dynamic SOX9 switch in repairing epithelia. Lineages that regenerated epithelia silenced SOX9 and healed without fibrosis (SOX9on-off). By contrast, lineages with unrestored apicobasal polarity maintained SOX9 activity in sustained efforts to regenerate, which were identified as a SOX9on-on Cadherin6pos cell state. These reprogrammed cells generated substantial single-cell WNT activity to provoke a fibroproliferative response in adjacent fibroblasts, driving AKI to chronic kidney disease. Transplanted human kidneys displayed similar SOX9/CDH6/WNT2B responses. Thus, we have uncovered a sensor of epithelial repair status, the activity of which determines regeneration with or without fibrosis.


Assuntos
Injúria Renal Aguda , Túbulos Renais Proximais , Rim , Insuficiência Renal Crônica , Fatores de Transcrição SOX9 , Animais , Humanos , Camundongos , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Células Epiteliais , Fibrose , Rim/patologia , Regeneração , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Fatores de Transcrição SOX9/genética , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo
12.
J Immunol ; 186(7): 4490-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21357532

RESUMO

Immune reconstitution plays a crucial role on the outcome of patients given T cell-depleted HLA-haploidentical hematopoietic stem cell transplantation (hHSCT) for hematological malignancies. CD1d-restricted invariant NKT (iNKT) cells are innate-like, lipid-reactive T lymphocytes controlling infections, cancer, and autoimmunity. Adult mature iNKT cells are divided in two functionally distinct CD4(+) and CD4(-) subsets that express the NK receptor CD161 and derive from thymic CD4(+)CD161(-) precursors. We investigated iNKT cell reconstitution dynamics in 33 pediatric patients given hHSCT for hematological malignancies, with a follow-up reaching 6 y posttransplantation, and correlated their emergence with disease relapse. iNKT cells fully reconstitute and rapidly convert into IFN-γ-expressing effectors in the 25 patients maintaining remission. CD4(+) cells emerge earlier than the CD4(-) ones, both displaying CD161(-) immature phenotypes. CD4(-) cells expand more slowly than CD4(+) cells, though they mature with significantly faster kinetics, reaching full maturation by 18 mo post-hHSCT. Between 4 and 6 y post-hHSCT, mature CD4(-) iNKT cells undergo a substantial expansion burst, resulting in a CD4(+)

Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Proliferação de Células , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas , Leucemia/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/transplante , Doença Aguda , Adolescente , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/transplante , Criança , Pré-Escolar , Feminino , Antígenos HLA/administração & dosagem , Humanos , Leucemia/patologia , Leucemia/terapia , Estudos Longitudinais , Masculino , Camundongos , Células T Matadoras Naturais/citologia , Indução de Remissão , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-38248494

RESUMO

In recent years, there has been a growing interest in the concept of trust within the domain of natural disaster management. Trust can be defined as a state of vulnerability where one party relies on another party with the expectation that the latter will carry out entrusted responsibilities without exploiting this inherent vulnerability. This comprehensive literature review is dedicated to the examination of research concerning community and institutional trust in the field of disaster risk reduction (DRR). Particular emphasis is placed on elucidating the influence of trust throughout the distinct phases of natural disaster management, namely prevention, preparedness, response, and recovery. The critical examination of the pertinent body of the literature demonstrates that trust plays a central role across the different phases of DRR, being positively associated with effective community responses and resilience. Hence, it becomes imperative to actively foster the development of trust at both institutional and community levels within the realm of DRR. This endeavor is essential for adequately preparing communities to confront natural disasters, crafting effective protocols to enhance community responsiveness and mitigate adverse consequences, and advancing strategies for successful reconstruction and recovery.


Assuntos
Planejamento em Desastres , Desastres , Desastres Naturais , Confiança , Desastres/prevenção & controle , Comportamento de Redução do Risco
14.
Front Physiol ; 14: 1107933, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008023

RESUMO

Spaceflight exposure, like prolonged skeletal unloading, is known to result in significant bone loss, but the molecular mechanisms responsible are still partly unknown. This impairment, characterizing both conditions, suggests the possibility of identifying common signalling pathways and developing innovative treatment strategies to counteract the bone loss typical of astronauts and osteoporotic patients. In this context, primary cell cultures of human osteoblasts derived from healthy subjects and osteoporotic patients were exposed to random positioning machine (RPM) to reproduce the absence of gravity and to exacerbate the pathological condition, respectively. The duration of exposure to RPM was 3 or 6 days, with the aim of determining whether a single administration of recombinant irisin (r-irisin) could prevent cell death and mineralizing capacity loss. In detail, cellular responses were assessed both in terms of death/survival, by MTS assay, analysis of oxidative stress and caspase activity, as well as the expression of survival and cell death proteins, and in terms of mineralizing capacity, by investigating the pentraxin 3 (PTX3) expression. Our results suggest that the effects of a single dose of r-irisin are maintained for a limited time, as demonstrated by complete protection after 3 days of RPM exposure and only partial protection when RPM exposure was for a longer time. Therefore, the use of r-irisin could be a valid strategy to counteract the bone mass loss induced by weightlessness and osteoporosis. Further studies are needed to determine an optimal treatment strategy based on the use of r-irisin that is fully protective even over very long periods of exposure and/or to identify further approaches to be used in a complementary manner.

15.
FEBS J ; 290(18): 4440-4464, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37166453

RESUMO

Astrocytes are essential players in development and functions, being particularly relevant as regulators of brain energy metabolism, ionic homeostasis and synaptic transmission. They are also the major source of l-serine in the brain, which is synthesized from the glycolytic intermediate 3-phosphoglycerate through the phosphorylated pathway. l-Serine is the precursor of the two main co-agonists of the N-methyl-d-aspartate receptor, glycine and d-serine. Strikingly, dysfunctions in both l- and d-serine metabolism are associated with neurological and psychiatric disorders. Here, we exploited a differentiation protocol, based on the generation of human mature astrocytes from neural stem cells, and investigated the modification of the proteomic and metabolomic profile during the differentiation process. We show that differentiated astrocytes are more similar to mature rather than to reactive ones, and that axogenesis and pyrimidine metabolism increase up to 30 days along with the folate cycle and sphingolipid metabolism. Consistent with the proliferation and cellular maturation processes that are taking place, also the intracellular levels of l-serine, glycine, threonine, l- and d-aspartate (which level is unexpectedly higher than that of d-serine) show the same biosynthetic time course. A significant utilization of l-serine from the medium is apparent while glycine is first consumed and then released with a peak at 30 days, parallel to its intracellular level. These results underline how metabolism changes during astrocyte differentiation, highlight that d-serine synthesis is restricted in differentiated astrocytes and provide a valuable model for developing potential novel therapeutic approaches to address brain diseases, especially the ones related to serine metabolism alterations.


Assuntos
Astrócitos , Células-Tronco Pluripotentes Induzidas , Humanos , Astrócitos/metabolismo , Serina/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteômica , Diferenciação Celular , Receptores de N-Metil-D-Aspartato/genética , Glicina/farmacologia , Glicina/metabolismo
16.
Eur J Immunol ; 41(3): 602-10, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21246542

RESUMO

CD1 molecules present lipid antigens to T cells. An intriguing subset of human T cells recognize CD1-expressing cells without deliberately added lipids. Frequency, subset distribution, clonal composition, naïve-to-memory dynamic transition of these CD1 self-reactive T cells remain largely unknown. By screening libraries of T-cell clones, generated from CD4(+) or CD4(-) CD8(-) double negative (DN) T cells sorted from the same donors, and by limiting dilution analysis, we find that the frequency of CD1 self-reactive T cells is unexpectedly high in both T-cell subsets, in the range of 1/10-1/300 circulating T cells. These T cells predominantly recognize CD1a and CD1c and express diverse TCRs. Frequency comparisons of T-cell clones from sorted naïve and memory compartments of umbilical cord and adult blood show that CD1 self-reactive T cells are naïve at birth and undergo an age-dependent increase in the memory compartment, suggesting a naïve/memory adaptive-like population dynamics. CD1 self-reactive clones exhibit mostly Th1 and Th0 functional activities, depending on the subset and on the CD1 isotype restriction. These findings unveil the unanticipated relevance of self-lipid T-cell response in humans and clarify the basic parameters of the lipid-specific T-cell physiology.


Assuntos
Antígenos CD1/metabolismo , Subpopulações de Linfócitos T/imunologia , Imunidade Adaptativa , Adulto , Apresentação de Antígeno , Autoantígenos , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Citotoxicidade Imunológica , Sangue Fetal/citologia , Sangue Fetal/imunologia , Humanos , Imunidade Celular , Memória Imunológica , Técnicas In Vitro , Recém-Nascido , Lipídeos/imunologia , Fenótipo , Receptores de Antígenos de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/citologia
18.
Life (Basel) ; 12(5)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35629278

RESUMO

Bone loss is among the most frequent changes seen in astronauts during space missions. Although weightlessness is known to cause high bone resorption and a rapid decrease in bone minerals and calcium, the underlying mechanisms are not yet fully understood. In our work, we investigated the influence of random positioning machine (RPM) exposure on the mineralization process in the SAOS-2 cell line, in osteogenic and non-osteogenic conditions, by examining changes in their mineralizing capacity and in the expression of PTX3, a positive regulator of bone mineralization. We analyzed cell viability by MTS assay and the mineralization process after staining with Toluidine Blue and Alizarin Red, while PTX3 expression was investigated by immunocytochemistry and western blotting analysis. Our results showed that RPM exposure increased cells' viability and improved their mineralizing competence when not treated with osteogenic cocktail. In contrast, in osteogenic conditions, cells exposed to RPM showed a reduction in the presence of calcification-like structures, mineral deposits and PTX3 expression, suggesting that the effects of RPM exposure on mineralizing matrix deposition depend on the presence of osteogenic factors in the culture medium. Further studies will be needed to clarify the role of potential mineralization markers in the cellular response to the simulated biological effects of microgravity, paving the way for a new approach to treating osteoporosis in astronauts exposed to spaceflight.

19.
Am J Cardiol ; 175: 152-157, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35597626

RESUMO

Anorexia nervosa (AN) is a psychiatric disorder that may lead to cardiac complications. The objective of this study was to evaluate global and regional longitudinal strain changes in patients affected by AN as an early marker of myocardial damage. We prospectively enrolled 48 consecutive patients with AN and 44 age-matched and gender-matched healthy controls. In all subjects, we performed echocardiography, including global longitudinal strain (GLS) measurement. A subset of 33 patients with AN had further echocardiographic examinations during the follow-up. Compared with healthy controls, patients with AN had a greater prevalence of pericardial effusion (9 of 48 vs 0 of 44, p = 0.003), a smaller left ventricular mass (63 ± 15 vs 99 ± 30 g, p < 0.001), a lower absolute value of GLS (-18.9 ± 2.8 vs -20.2 ± 1.8%, p = 0.010) and of basal LS (-15.4 ± 6.0 vs -19.4 ± 2.6%, p < 0.001). The bull's eye mapping showed a plot pattern with blue basal areas in 18 of 48 patients with AN versus 1 of 44 controls (p < 0.001). During the follow-up, of 13 patients with blue areas in the first bull's eye mapping, 11 recovered completely, and of 20 patients with a red bull's eye at the first examination, none presented blue areas at the second one. In conclusion, GLS is significantly altered in patients with AN, and a basal blue pattern on bull's eye mapping identifies more severe cases. These changes seem to be reversible.


Assuntos
Anorexia Nervosa , Cardiopatias , Adulto , Anorexia Nervosa/complicações , Ecocardiografia , Cardiopatias/complicações , Humanos , Função Ventricular Esquerda
20.
Nat Commun ; 13(1): 2177, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449130

RESUMO

Cells subjected to treatment with anti-cancer therapies can evade apoptosis through cellular senescence. Persistent senescent tumor cells remain metabolically active, possess a secretory phenotype, and can promote tumor proliferation and metastatic dissemination. Removal of senescent tumor cells (senolytic therapy) has therefore emerged as a promising therapeutic strategy. Here, using single-cell RNA-sequencing, we find that senescent tumor cells rely on the anti-apoptotic gene Mcl-1 for their survival. Mcl-1 is upregulated in senescent tumor cells, including cells expressing low levels of Bcl-2, an established target for senolytic therapy. While treatment with the Bcl-2 inhibitor Navitoclax results in the reduction of metastases in tumor bearing mice, treatment with the Mcl-1 inhibitor S63845 leads to complete elimination of senescent tumor cells and metastases. These findings provide insights on the mechanism by which senescent tumor cells survive and reveal a vulnerability that can be exploited for cancer therapy.


Assuntos
Antineoplásicos , Neoplasias , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/genética , Senescência Celular/genética , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transcriptoma
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