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1.
Front Cell Infect Microbiol ; 14: 1363407, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590437

RESUMO

Introduction: Influenza A virus (IAV) infection can cause the often-lethal acute respiratory distress syndrome (ARDS) of the lung. Concomitantly, acute kidney injury (AKI) is frequently noticed during IAV infection, correlating with an increased mortality. The aim of this study was to elucidate the interaction of IAV with human kidney cells and, thereby, to assess the mechanisms underlying IAV-mediated AKI. Methods: To investigate IAV effects on nephron cells we performed infectivity assays with human IAV, as well as with human isolates of either low or highly pathogenic avian IAV. Also, transcriptome and proteome analysis of IAV-infected primary human distal tubular kidney cells (DTC) was performed. Furthermore, the DTC transcriptome was compared to existing transcriptomic data from IAV-infected lung and trachea cells. Results: We demonstrate productive replication of all tested IAV strains on primary and immortalized nephron cells. Comparison of our transcriptome and proteome analysis of H1N1-type IAV-infected human primary distal tubular cells (DTC) with existing data from H1N1-type IAV-infected lung and primary trachea cells revealed enrichment of specific factors responsible for regulated cell death in primary DTC, which could be targeted by specific inhibitors. Discussion: IAV not only infects, but also productively replicates on different human nephron cells. Importantly, multi-omics analysis revealed regulated cell death as potential contributing factor for the clinically observed kidney pathology in influenza.


Assuntos
Injúria Renal Aguda , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Infecções por Orthomyxoviridae , Morte Celular Regulada , Humanos , Proteoma/metabolismo , Vírus da Influenza A Subtipo H3N2/fisiologia , Replicação Viral/fisiologia , Rim/patologia , Infecções por Orthomyxoviridae/patologia
2.
Ind Health ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38556261

RESUMO

The study tested a brief intervention to stimulate and help supervisors reduce work-related interruptions among their employees, both at work and during leisure time. The core of the short-term intervention was a workplace analysis of work-related interruptions, which was fed back to supervisors in combination with a work redesign stimulation explaining why and how to reduce interruptions. Two intervention sessions, as one-on-one physical meetings, that lasted 1.5 h each and were 2 wk apart. The sample consisted of 20 managers and 89 employees. The non-experimental repeated measurement design comprised three questionnaire measurements of the 89 employees (two pre-measurements and one post-measurement). Repeated measure hierarchical linear models showed that the intervention significantly predicted reduced interruptions during work and work-related interruptions of leisure time. Although the intervention effect sizes were small, the current work design intervention with supervisors as mediating actors can reasonably contribute to occupational health prevention.

3.
Virus Res ; 342: 199337, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38346476

RESUMO

Marburg virus, a member of the Filoviridae, is the causative agent of Marburg virus disease (MVD), a hemorrhagic fever with a case fatality rate of up to 90 %. Acute kidney injury is common in MVD and is associated with increased mortality, but its pathogenesis in MVD remains poorly understood. Interestingly, autopsies show the presence of viral proteins in different parts of the nephron, particularly in proximal tubular cells (PTC). These findings suggest a potential role for the virus in the development of MVD-related kidney injury. To shed light on this effect, we infected primary human PTC with Lake Victoria Marburg virus and conducted transcriptomic analysis at multiple time points. Unexpectedly, infection did not induce marked cytopathic effects in primary tubular cells at 20 and 40 h post infection. However, gene expression analysis revealed robust renal viral replication and dysregulation of genes essential for different cellular functions. The gene sets mainly downregulated in PTC were associated with the targets of the transcription factors MYC and E2F, DNA repair, the G2M checkpoint, as well as oxidative phosphorylation. Importantly, the downregulated factors comprise PGC-1α, a well-known factor in acute and chronic kidney injury. By contrast, the most highly upregulated gene sets were those related to the inflammatory response and cholesterol homeostasis. In conclusion, Marburg virus infects and replicates in human primary PTC and induces downregulation of processes known to be relevant for acute kidney injury as well as a strong inflammatory response.


Assuntos
Injúria Renal Aguda , Marburgvirus , Humanos , Animais , Marburgvirus/genética , Metabolismo Energético , Perfilação da Expressão Gênica , Imunidade
4.
Science ; 383(6690): eabn3263, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422184

RESUMO

Vocal production learning ("vocal learning") is a convergently evolved trait in vertebrates. To identify brain genomic elements associated with mammalian vocal learning, we integrated genomic, anatomical, and neurophysiological data from the Egyptian fruit bat (Rousettus aegyptiacus) with analyses of the genomes of 215 placental mammals. First, we identified a set of proteins evolving more slowly in vocal learners. Then, we discovered a vocal motor cortical region in the Egyptian fruit bat, an emergent vocal learner, and leveraged that knowledge to identify active cis-regulatory elements in the motor cortex of vocal learners. Machine learning methods applied to motor cortex open chromatin revealed 50 enhancers robustly associated with vocal learning whose activity tended to be lower in vocal learners. Our research implicates convergent losses of motor cortex regulatory elements in mammalian vocal learning evolution.


Assuntos
Elementos Facilitadores Genéticos , Eutérios , Evolução Molecular , Regulação da Expressão Gênica , Córtex Motor , Neurônios Motores , Proteínas , Vocalização Animal , Animais , Quirópteros/genética , Quirópteros/fisiologia , Vocalização Animal/fisiologia , Córtex Motor/citologia , Córtex Motor/fisiologia , Cromatina/metabolismo , Neurônios Motores/fisiologia , Laringe/fisiologia , Epigênese Genética , Genoma , Proteínas/genética , Proteínas/metabolismo , Sequência de Aminoácidos , Eutérios/genética , Eutérios/fisiologia , Aprendizado de Máquina
5.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069304

RESUMO

Despite the importance of rapid adaptive responses in the course of inflammation and the notion that post-transcriptional regulation plays an important role herein, relevant translational alterations, especially during the resolution phase, remain largely elusive. In the present study, we analyzed translational changes in inflammatory bone marrow-derived macrophages upon resolution-promoting efferocytosis. Total RNA-sequencing confirmed that apoptotic cell phagocytosis induced a pro-resolution signature in LPS/IFNγ-stimulated macrophages (Mϕ). While inflammation-dependent transcriptional changes were relatively small between efferocytic and non-efferocytic Mϕ; considerable differences were observed at the level of de novo synthesized proteins. Interestingly, translationally regulated targets in response to inflammatory stimuli were mostly downregulated, with only minimal impact of efferocytosis. Amongst these targets, pro-resolving matrix metallopeptidase 12 (Mmp12) was identified as a translationally repressed candidate during early inflammation that recovered during the resolution phase. Functionally, reduced MMP12 production enhanced matrix-dependent migration of Mϕ. Conclusively, translational control of MMP12 emerged as an efficient strategy to alter the migratory properties of Mϕ throughout the inflammatory response, enabling Mϕ migration within the early inflammatory phase while restricting migration during the resolution phase.


Assuntos
Metaloproteinase 12 da Matriz , Fagocitose , Humanos , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 12 da Matriz/metabolismo , Fagocitose/fisiologia , Macrófagos/metabolismo , Inflamação/metabolismo , Regulação da Expressão Gênica , Apoptose/fisiologia
6.
Biology (Basel) ; 12(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37998039

RESUMO

Macrophages are a highly versatile and heterogenic group of immune cells, known for their involvement in inflammatory reactions. However, our knowledge about distinct subpopulations of macrophages and their specific contribution to the resolution of inflammation remains incomplete. We have previously shown, in an in vivo peritonitis model, that inhibition of the synthesis of the pro-inflammatory lipid mediator prostaglandin E2 (PGE2) attenuates efficient resolution of inflammation. PGE2 levels during later stages of the inflammatory process further correlate with expression of the hyaluronan (HA) receptor Lyve1 in peritoneal macrophages. In the present study, we therefore aimed to understand if PGE2 might contribute to the regulation of Lyve1 and how this might impact inflammatory responses. In line with our in vivo findings, PGE2 synergized with dexamethasone to enhance Lyve1 expression in bone marrow-derived macrophages, while expression of the predominant hyaluronan receptor CD44 remained unaltered. PGE2-mediated Lyve1 upregulation was strictly dependent on PGE2 receptor EP2 signaling. While PGE2/dexamethasone-treated macrophages, despite their enhanced Lyve1 expression, did not show inflammatory responses upon stimulation with low (LMW) or high-molecular-weight hyaluronan (HMW)-HA, they were sensitized towards LMW-HA-dependent augmentation of lipopolysaccharide (LPS)-induced inflammatory responses. Thus, Lyve1-expressing macrophages emerged as a subpopulation of macrophages integrating inflammatory stimuli with extracellular matrix-derived signals.

7.
Cell Biosci ; 13(1): 155, 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37635256

RESUMO

BACKGROUND: Pain in early life may impact on development and risk of chronic pain. We developed an optogenetic Cre/loxP mouse model of "early-life-pain" (ELP) using mice with transgenic expression of channelrhodopsin-2 (ChR2) under control of the Advillin (Avil) promoter, which drives expression of transgenes predominantly in isolectin B4 positive non-peptidergic nociceptors in postnatal mice. Avil-ChR2 (Cre +) and ChR2-flfl control mice were exposed to blue light in a chamber once daily from P1-P5 together with their Cre-negative mother. RESULTS: ELP caused cortical hyperexcitability at P8-9 as assessed via multi-electrode array recordings that coincided with reduced expression of synaptic genes (RNAseq) including Grin2b, neurexins, piccolo and voltage gated calcium and sodium channels. Young adult (8-16 wks) Avil-ChR2 mice presented with nociceptive hypersensitivity upon heat or mechanical stimulation, which did not resolve up until one year of age. The persistent hypersensitivy to nociceptive stimuli was reflected by increased calcium fluxes in primary sensory neurons of aged mice (1 year) upon capsaicin stimulation. Avil-ChR2 mice behaved like controls in maze tests of anxiety, social interaction, and spatial memory but IntelliCage behavioral studies revealed repetitive nosepokes and corner visits and compulsive lickings. Compulsiveness at the behavioral level was associated with a reduction of sphingomyelin species in brain and plasma lipidomic studies. Behavioral studies were done with female mice. CONCLUSION: The results suggest that ELP may predispose to chronic "pain" and compulsive psychopathology in part mediated by alterations of sphingolipid metabolism, which have been previously described in the context of addiction and psychiatric diseases.

8.
Front Immunol ; 14: 1121864, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377965

RESUMO

Hypoxia contributes to numerous pathophysiological conditions including inflammation-associated diseases. We characterized the impact of hypoxia on the immunometabolic cross-talk between cholesterol and interferon (IFN) responses. Specifically, hypoxia reduced cholesterol biosynthesis flux and provoked a compensatory activation of sterol regulatory element-binding protein 2 (SREBP2) in monocytes. Concomitantly, a broad range of interferon-stimulated genes (ISGs) increased under hypoxia in the absence of an inflammatory stimulus. While changes in cholesterol biosynthesis intermediates and SREBP2 activity did not contribute to hypoxic ISG induction, intracellular cholesterol distribution appeared critical to enhance hypoxic expression of chemokine ISGs. Importantly, hypoxia further boosted chemokine ISG expression in monocytes upon infection with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Mechanistically, hypoxia sensitized toll-like receptor 4 (TLR4) signaling to activation by SARS-CoV-2 spike protein, which emerged as a major signaling hub to enhance chemokine ISG induction following SARS-CoV-2 infection of hypoxic monocytes. These data depict a hypoxia-regulated immunometabolic mechanism with implications for the development of systemic inflammatory responses in severe cases of coronavirus disease-2019 (COVID-19).


Assuntos
COVID-19 , Interferons , Humanos , Interferons/farmacologia , Monócitos , SARS-CoV-2 , Quimiocinas , Hipóxia , Colesterol
9.
Front Pharmacol ; 14: 1121819, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36744258

RESUMO

The importance of biologically active lipid mediators, such as prostanoids, leukotrienes, and specialized pro-resolving mediators, in the regulation of inflammation is well established. While the relevance of cholesterol in the context of atherosclerosis is also widely accepted, the role of cholesterol and its biosynthetic precursors on inflammatory processes is less comprehensively described. In the present mini-review, we summarize the current understanding of the inflammation-regulatory properties of cholesterol and relevant biosynthetic intermediates taking into account the implications of different subcellular distributions. Finally, we discuss the inflammation-regulatory effect of cholesterol homeostasis in the context of SARS-CoV-2 infections.

10.
Cancer Gene Ther ; 30(1): 108-123, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36114329

RESUMO

5-Lipoxygenase (5-LO), the central enzyme in the biosynthesis of leukotrienes, is frequently expressed in human solid malignancies even though the enzyme is not present in the corresponding healthy tissues. There is little knowledge on the consequences of this expression for the tumor cells regarding gene expression and cellular function. We established a knockout (KO) of 5-LO in different cancer cell lines (HCT-116, HT-29, U-2 OS) and studied the consequences on global gene expression using next generation sequencing. Furthermore, cell viability, proliferation, migration and multicellular tumor spheroid (MCTS) formation were studied in these cells. Our results show that 5-LO influences the gene expression and cancer cell function in a cell type-dependent manner. The enzyme affected genes involved in cell adhesion, extracellular matrix formation, G protein signaling and cytoskeleton organization. Furthermore, absence of 5-LO elevated TGFß2 expression in HCT-116 cells while MCP-1, fractalkine and platelet-derived growth factor expression was attenuated in U-2 OS cells suggesting that tumor cell-derived 5-LO shapes the tumor microenvironment. In line with the gene expression data, KO of 5-LO had an impact on cell proliferation, motility and MCTS formation. Interestingly, pharmacological inhibition of 5-LO only partly mimicked the KO suggesting that also noncanonical functions are involved.


Assuntos
Araquidonato 5-Lipoxigenase , Neoplasias , Humanos , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Linhagem Celular , Transdução de Sinais , Neoplasias/genética , Expressão Gênica , Araquidonato 15-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/metabolismo , Microambiente Tumoral
11.
Cells ; 11(17)2022 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36078082

RESUMO

BACKGROUND: Sorafenib constitutes a suitable treatment alternative for patients with advanced hepatocellular carcinoma (HCC) in whom atezolizumab + bevacizumab therapy is contraindicated. The aim of the study was the identification of a miRNA signature in liquid biopsy related to sorafenib response. METHODS: miRNAs were profiled in hepatoblastoma HepG2 cells and tested in animal models, extracellular vesicles (EVs), and plasma from HCC patients. RESULTS: Sorafenib altered the expression of 11 miRNAs in HepG2 cells. miR-200c-3p and miR-27a-3p exerted an anti-tumoral activity by decreasing cell migration and invasion, whereas miR-122-5p, miR-148b-3p, miR-194-5p, miR-222-5p, and miR-512-3p exerted pro-tumoral properties by increasing cell proliferation, migration, or invasion, or decreasing apoptosis. Sorafenib induced a change in EVs population with an increased number of larger EVs, and promoted an accumulation of miR-27a-3p, miR-122-5p, miR-148b-3p, miR-193b-3p, miR-194-5p, miR-200c-3p, and miR-375 into exosomes. In HCC patients, circulating miR-200c-3p baseline levels were associated with increased survival, whereas high levels of miR-222-5p and miR-512-3p after 1 month of sorafenib treatment were related to poor prognosis. The RNA sequencing revealed that miR-200c-3p was related to the regulation of cell growth and death, whereas miR-222-5p and miR-512-3p were related to metabolic control. CONCLUSIONS: The study showed that Sorafenib regulates a specific miRNA signature in which miR-200c-3p, miR-222-5p, and miR-512-3p bear prognostic value and contribute to treatment response.


Assuntos
Carcinoma Hepatocelular , MicroRNAs , Sorafenibe , Biomarcadores , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico
12.
Biochem Pharmacol ; 203: 115187, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35878796

RESUMO

Human 5-lipoxygenase (5-LO) is the key enzyme of leukotriene biosynthesis, mostly expressed in leukocytes and thus a crucial component of the innate immune system. In this study, we show that 5-LO, besides its canonical function as an arachidonic acid metabolizing enzyme, is a regulator of gene expression associated with euchromatin. By Crispr-Cas9-mediated 5-LO knockout (KO) in MonoMac6 (MM6) cells and subsequent RNA-Seq analysis, we identified 5-LO regulated genes which could be clustered to immune/defense response, cell adhesion, transcription and growth/developmental processes. Analysis of differentially expressed genes identified cyclooxygenase-2 (COX2, PTGS2) and kynureninase (KYNU) as strongly regulated 5-LO target genes. 5-LO knockout affected MM6 cell adhesion and tryptophan metabolism via inhibition of the degradation of the immunoregulator kynurenine. By subsequent FAIRE-Seq and 5-LO ChIP-Seq analyses, we found an association of 5-LO with euchromatin, with prominent 5-LO binding to promoter regions in actively transcribed genes. By enrichment analysis of the ChIP-Seq results, we identified potential 5-LO interaction partners. Furthermore, 5-LO ChIP-Seq peaks resemble patterns of H3K27ac histone marks, suggesting that 5-LO recruitment mainly takes place at acetylated histones. In summary, we demonstrate a noncanonical function of 5-LO as transcriptional regulator in monocytic cells.


Assuntos
Araquidonato 5-Lipoxigenase , Eucromatina , Araquidonato 15-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Eucromatina/genética , Histonas/metabolismo , Humanos , Metabolismo dos Lipídeos , Lipoxigenase/genética , Lipoxigenase/metabolismo
14.
IEEE Trans Biomed Circuits Syst ; 16(3): 419-429, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35622811

RESUMO

Conductive intracardiac communication (CIC) has been demonstrated as a promising concept for the synchronization of multi-chamber leadless cardiac pacemakers (LLPMs). To meet the 2-5 µW power budget of a LLPM, highly specialized CIC-transceivers, which make optimal use of the cardiac communication channel, need to be developed. However, a detailed investigation of the optimal communication parameters for CIC-based LLPM synchronization is missing so far. This work analyzes the intracardiac communication performance of two low-power modulation techniques, namely On-Off-Keying (OOK) and Manchester-encoded baseband transmission (BB-MAN), as a function of the transmitted bit-energy. The bit error rate (BER) of a prototype dual-chamber LLPM was determined both in simulation and in-vitro experiments on porcine hearts. A BER of 1e -4 was achieved with a median bit-energy in the range of 3-16 pJ (interquartile range: 4-15 pJ) for data rates from 75-500 kbps and a receiver input noise density of 7 nV/ √{Hz}. Both modulation schemes showed comparable performance, with BB-MAN having a slight bit-energy advantage (1-2 dB at 150-500 kbps) under equalized transceiver characteristics. This study demonstrates that reliable CIC-based LLPM synchronization is feasible at transmitted power levels 10 nW under realistic channel conditions and receiver noise performance. Therefore, modulation techniques such, as BB-MAN or OOK, are preferable over recently proposed alternatives, such as pulse position modulation or conductive impulse signaling, since they can be realized with fewer hardware resources and smaller bandwidth requirements. Ultimately, a baseband communication approach might be favored over OOK, due to the more efficient cardiac signal transmission and reduced transceiver complexity.


Assuntos
Arritmias Cardíacas , Marca-Passo Artificial , Animais , Comunicação , Desenho de Equipamento , Coração , Humanos , Suínos
15.
Int J Mol Sci ; 23(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35628634

RESUMO

Previous studies towards reduced oxygen availability have mostly focused on changes in total mRNA expression, neglecting underlying transcriptional and post-transcriptional events. Therefore, we generated a comprehensive overview of hypoxia-induced changes in total mRNA expression, global de novo transcription, and mRNA stability in monocytic THP-1 cells. Since hypoxic episodes often persist for prolonged periods, we further compared the adaptation to acute and chronic hypoxia. While total mRNA changes correlated well with enhanced transcription during short-term hypoxia, mRNA destabilization gained importance under chronic conditions. Reduced mRNA stability not only added to a compensatory attenuation of immune responses, but also, most notably, to the reduction in nuclear-encoded mRNAs associated with various mitochondrial functions. These changes may prevent the futile production of new mitochondria under conditions where mitochondria cannot exert their full metabolic function and are indeed actively removed by mitophagy. The post-transcriptional mode of regulation might further allow for the rapid recovery of mitochondrial capacities upon reoxygenation. Our results provide a comprehensive resource of functional mRNA expression dynamics and underlying transcriptional and post-transcriptional regulatory principles during the adaptation to hypoxia. Furthermore, we uncover that RNA stability regulation controls mitochondrial functions in the context of hypoxia.


Assuntos
Regulação da Expressão Gênica , Hipóxia , Aclimatação , Humanos , Hipóxia/genética , Hipóxia/metabolismo , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Curr Biol ; 32(13): 2935-2941.e3, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35617952

RESUMO

Bats have evolved behavioral specializations that are unique among mammals, including self-propelled flight and echolocation. However, areas of motor cortex that are critical in the generation and fine control of these unique behaviors have never been fully characterized in any bat species, despite the fact that bats compose ∼25% of extant mammalian species. Using intracortical microstimulation, we examined the organization of motor cortex in Egyptian fruit bats (Rousettus aegyptiacus), a species that has evolved a novel form of tongue-based echolocation.1,2 We found that movement representations include an enlarged tongue region containing discrete subregions devoted to generating distinct tongue movement types, consistent with their behavioral specialization generating active sonar using tongue clicks. This magnification of the tongue in motor cortex is comparable to the enlargement of somatosensory representations in species with sensory specializations.3-5 We also found a novel degree of coactivation between the forelimbs and hindlimbs, both of which are involved in altering the shape and tension of wing membranes during flight. Together, these findings suggest that the organization of motor cortex has coevolved with peripheral morphology in bats to support the unique motor demands of flight and echolocation.


Assuntos
Quirópteros , Ecolocação , Córtex Motor , Animais , Quirópteros/fisiologia , Ecolocação/fisiologia , Voo Animal/fisiologia , Som , Asas de Animais
17.
Cancer Res ; 82(8): 1617-1632, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35425959

RESUMO

An altered lipidome in tumors may affect not only tumor cells themselves but also their microenvironment. In this study, a lipidomics screen reveals increased amounts of phosphatidylserine (PS), particularly ether-PS (ePS), in murine mammary tumors compared with normal tissue. PS was produced by phosphatidylserine synthase 1 (PTDSS1), and depletion of Ptdss1 from tumor cells in mice reduced ePS levels accompanied by stunted tumor growth and decreased tumor-associated macrophage (TAM) abundance. Ptdss1-deficient tumor cells exposed less PS during apoptosis, which was recognized by the PS receptor MERTK. Mammary tumors in macrophage-specific Mertk-/- mice showed similarly suppressed growth and reduced TAM infiltration. Transcriptomic profiles of TAMs from Ptdss1-knockdown tumors and Mertk-/- TAMs revealed that macrophage proliferation was reduced when the Ptdss1/Mertk pathway was targeted. Moreover, PTDSS1 expression correlated positively with TAM abundance but negatively with breast carcinoma patient survival. PTDSS1 thus may be a target to modify tumor-promoting inflammation. SIGNIFICANCE: This study shows that inhibiting the production of ether-phosphatidylserine by targeting phosphatidylserine synthase PTDSS1 limits tumor-associated macrophage expansion and breast tumor growth.


Assuntos
Lipidômica , Neoplasias , Animais , CDPdiacilglicerol-Serina O-Fosfatidiltransferase , Éter , Humanos , Inflamação/metabolismo , Camundongos , Neoplasias/metabolismo , Fosfatidilserinas/metabolismo , Microambiente Tumoral , c-Mer Tirosina Quinase/metabolismo
18.
Nature ; 604(7904): 98-103, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35355012

RESUMO

Neural activity in the hippocampus is known to reflect how animals move through an environment1,2. Although navigational behaviour may show considerable stability3-6, the tuning stability of individual hippocampal neurons remains unclear7-12. Here we used wireless calcium imaging to longitudinally monitor the activity of dorsal CA1 hippocampal neurons in freely flying bats performing highly reproducible flights in a familiar environment. We find that both the participation and the spatial selectivity of most neurons remain stable over days and weeks. We also find that apparent changes in tuning can be largely attributed to variations in the flight behaviour of the bats. Finally, we show that bats navigating in the same environment under different room lighting conditions (lights on versus lights off) exhibit substantial changes in flight behaviour that can give the illusion of neuronal instability. However, when similar flight paths are compared across conditions, the stability of the hippocampal code persists. Taken together, we show that the underlying hippocampal code is highly stable over days and across contexts if behaviour is taken into account.


Assuntos
Região CA1 Hipocampal , Quirópteros , Neurônios , Animais , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Cálcio , Quirópteros/fisiologia , Voo Animal/fisiologia , Iluminação , Neurônios/fisiologia , Navegação Espacial/fisiologia
19.
Biology (Basel) ; 11(3)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35336722

RESUMO

Macrophages constitute a major part of the tumor-infiltrating immune cells. Within the tumor microenvironment, they acquire an alternatively activated, tumor-supporting phenotype. Factors released by tumor cells are crucial for the recruitment of tumor-associated macrophages. In the present project, we aimed to understand the role of hsa-miR-200c-3p (miR-200c) in the interplay between tumor cells and macrophages. To this end, we employed a coculture system of MCF7 breast tumor cells and primary human macrophages and observed the transfer of miR-200c from apoptotic tumor cells to macrophages, which required intact CD36 receptor in macrophages. We further comprehensively determined miR-200c targets in macrophages by mRNA-sequencing and identified numerous migration-associated mRNAs to be downregulated by miR-200c. Consequently, miR-200c attenuated macrophage infiltration into 3-dimensional tumor spheroids. miR-200c-mediated reduction in infiltration further correlated with a miR-200c migration signature comprised of the four miR-200c-repressed, predicted targets PPM1F, RAB11FIB2, RDX, and MSN.

20.
Science ; 374(6566): eaba9584, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34672724

RESUMO

Social interactions occur in group settings and are mediated by communication signals that are exchanged between individuals, often using vocalizations. The neural representation of group social communication remains largely unexplored. We conducted simultaneous wireless electrophysiological recordings from the frontal cortices of groups of Egyptian fruit bats engaged in both spontaneous and task-induced vocal interactions. We found that the activity of single neurons distinguished between vocalizations produced by self and by others, as well as among specific individuals. Coordinated neural activity among group members exhibited stable bidirectional interbrain correlation patterns specific to spontaneous communicative interactions. Tracking social and spatial arrangements within a group revealed a relationship between social preferences and intra- and interbrain activity patterns. Combined, these findings reveal a dedicated neural repertoire for group social communication within and across the brains of freely communicating groups of bats.


Assuntos
Quirópteros/fisiologia , Ecolocação , Lobo Frontal/fisiologia , Comportamento Social , Vocalização Animal , Animais , Quirópteros/psicologia , Diencéfalo/fisiologia , Feminino , Masculino , Interação Social
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