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1.
J Cell Biol ; 222(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36219157

RESUMO

Cytokinesis requires the constriction of an actomyosin-based contractile ring and involves multiple F-actin crosslinkers. We show that partial depletion of the C. elegans cytokinetic formin generates contractile rings with low F-actin levels that constrict but are structurally fragile, and we use this background to investigate the roles of the crosslinkers plastin/PLST-1 and ß-heavy-spectrin/SMA-1 during ring constriction. We show that the removal of PLST-1 or SMA-1 has opposite effects on the structural integrity of fragile rings. PLST-1 loss reduces cortical tension that resists ring constriction and makes fragile rings less prone to ruptures and regressions, whereas SMA-1 loss exacerbates structural defects, leading to frequent ruptures and cytokinesis failure. Fragile rings without SMA-1 or containing a shorter SMA-1, repeatedly rupture at the same site, and SMA-1::GFP accumulates at repair sites in fragile rings and in rings cut by laser microsurgery. These results establish that ß-heavy-spectrin stabilizes the constricting ring and reveals the importance of ß-heavy-spectrin size for network connectivity at low F-actin density.


Assuntos
Citoesqueleto de Actina , Citocinese , Espectrina , Actinas , Actomiosina , Animais , Caenorhabditis elegans/citologia , Proteínas de Caenorhabditis elegans/metabolismo , Forminas , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Espectrina/metabolismo
2.
J Biomed Mater Res B Appl Biomater ; 111(1): 51-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35799479

RESUMO

Spinal cord injury (SCI) will lead to irreversible damage of sensory and motor function of central nervous system, which seriously affects patient's quality of life. A variety of nerve engineering materials carrying various stem cells and cell growth factors had used to promote the repair of SCI, but they could not mimic the actual matric niche at spinal cord to promote cell proliferation and differentiation. Thus, developing novel biomaterial providing better niche of spinal cord is a new strategy to treat the severe SCI. In this study, we constructed porcine spinal cord decellularized matrix scaffold (SC-DM) with biocompatibility to load engineered basic fibroblast growth factor-overexpressing human umbilical cord mesenchymal stromal cells (bFGF-HUCMSCs) for treating SCI. The continuously released bioactive bFGF factors from grafted bFGF-HUCMSCs and three-dimensional niche by SC-DM promoted the differentiation of endogenous stem cells into neurons with nerve conduction function, leading a markedly motor function recovery of SCI. These results indicated that the functional bFGF-HUCMSCs/SC-DM scaffold provided more suitable matric niche for nerve cells, that would be a promising strategy for the clinical application of SCI.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Humanos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Qualidade de Vida , Traumatismos da Medula Espinal/metabolismo , Tecidos Suporte , Cordão Umbilical/citologia , Animais
3.
J Cell Biol ; 222(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36409222

RESUMO

In Drosophila melanogaster, the anterior-posterior body axis is maternally established and governed by differential localization of partitioning defective (Par) proteins within the oocyte. At mid-oogenesis, Par-1 accumulates at the oocyte posterior end, while Par-3/Bazooka is excluded there but maintains its localization along the remaining oocyte cortex. Past studies have proposed the need for somatic cells at the posterior end to initiate oocyte polarization by providing a trigger signal. To date, neither the molecular identity nor the nature of the signal is known. Here, we provide evidence that mechanical contact of posterior follicle cells (PFCs) with the oocyte cortex causes the posterior exclusion of Bazooka and maintains oocyte polarity. We show that Bazooka prematurely accumulates exclusively where posterior follicle cells have been mechanically detached or ablated. Furthermore, we provide evidence that PFC contact maintains Par-1 and oskar mRNA localization and microtubule cytoskeleton polarity in the oocyte. Our observations suggest that cell-cell contact mechanics modulates Par protein binding sites at the oocyte cortex.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Folículo Ovariano , Animais , Feminino , Padronização Corporal , Polaridade Celular , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/fisiologia , Oócitos/fisiologia , Folículo Ovariano/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia
4.
J Cell Biol ; 222(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36399182

RESUMO

Maintaining long, energetically demanding axons throughout the life of an animal is a major challenge for the nervous system. Specialized glia ensheathe axons and support their function and integrity throughout life, but glial support mechanisms remain poorly defined. Here, we identified a collection of secreted and transmembrane molecules required in glia for long-term axon survival in vivo. We showed that the majority of components of the TGFß superfamily are required in glia for sensory neuron maintenance but not glial ensheathment of axons. In the absence of glial TGFß signaling, neurons undergo age-dependent degeneration that can be rescued either by genetic blockade of Wallerian degeneration or caspase-dependent death. Blockade of glial TGFß signaling results in increased ATP in glia that can be mimicked by enhancing glial mitochondrial biogenesis or suppressing glial monocarboxylate transporter function. We propose that glial TGFß signaling supports axon survival and suppresses neurodegeneration through promoting glial metabolic support of neurons.


Assuntos
Axônios , Neuroglia , Fator de Crescimento Transformador beta , Animais , Axônios/metabolismo , Neuroglia/metabolismo , Nervos Periféricos/citologia , Células Receptoras Sensoriais , Fator de Crescimento Transformador beta/metabolismo , Drosophila melanogaster , Biogênese de Organelas , Transportadores de Ácidos Monocarboxílicos/metabolismo
5.
Nature ; 611(7934): 24-27, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36323815
6.
BMC Med ; 20(1): 388, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36316769

RESUMO

BACKGROUND: Breastmilk is a dynamic fluid whose initial function is to provide the most adapted nutrition to the neonate. Additional attributes have been recently ascribed to breastmilk, with the evidence of a specific microbiota and the presence of various components of the immune system, such as cytokines and leukocytes. The composition of breastmilk varies through time, according to the health status of mother and child, and altogether contributes to the future health of the infant. Obesity is a rising condition worldwide that creates a state of systemic, chronic inflammation including leukocytosis. Here, we asked whether colostrum, the milk produced within the first 48 h post-partum, would contain a distinct leukocyte composition depending on the body mass index (BMI) of the mother. METHODS: We collected peripheral blood and colostrum paired samples from obese (BMI > 30) and lean (BMI < 25) mothers within 48 h post-partum and applied a panel of 6 antibodies plus a viability marker to characterize 10 major leukocyte subpopulations using flow cytometry. RESULTS: The size, internal complexity, and surface expression of CD45 and CD16 of multiple leukocyte subpopulations were selectively regulated between blood and colostrum irrespective of the study groups, suggesting a generalized cell-specific phenotype alteration. In obesity, the colostrum B lymphocyte compartment was significantly reduced, and CD16+ blood monocytes had an increased CD16 expression compared to the lean group. CONCLUSIONS: This is the first characterization of major leukocyte subsets in colostrum of mothers suffering from obesity and the first report of colostrum leukocyte subpopulations in Latin America. We evidence various significant alterations of most leukocyte populations between blood and colostrum and demonstrate a decreased colostrum B lymphocyte fraction in obesity. This pioneering study is a stepping stone to further investigate active immunity in human breastmilk.


Assuntos
Colostro , Leucócitos , Leite Humano , Obesidade , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Colostro/citologia , Estudos Transversais , Leite Humano/citologia , Mães
7.
Vet Immunol Immunopathol ; 253: 110508, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36327943

RESUMO

Staphylococcus aureus mastitis constitutes a serious threat to dairy cows. The reasons why available vaccines are not fully effective remain poorly understood; thus, in the present study, we investigated CD4+ and CD8+ T lymphocyte proliferation in dairy cows vaccinated with a polyvalent mastitis vaccine that had distinct precedent Staphylococcus aureus mastitis. We studied 17 S. aureus-infected dairy cows (11 vaccinated and six unvaccinated) and eight vaccinated healthy dairy cows with no previous S. aureus mastitis infections. Flow cytometry was used to assess lymphocyte proliferation using an anti-Ki67 antibody, and monoclonal antibodies were used to identify T cell subsets. S. aureus-infected cows exhibited reduced overall lymphocyte proliferation, including CD4+ T lymphocyte proliferation, and memory lymphocyte proliferation in response to S. aureus isolate stimulus. Immunization did not influence the expansion of blood lymphocyte populations. Furthermore, CD8+ T cells, memory CD8+ T lymphocytes, and effector memory CD8+ T lymphocytes displayed reduced proliferation 21 days after the third vaccine dose compared with before vaccination at time zero. The present data demonstrates an overall negative regulation of the T-cell response suggesting its detrimental impact leading to the persistence of S. aureus intramammary infections. Furthermore, the lack of vaccination effect on T-cell mediated immunity (e.g., proliferation) may be related to poor vaccine efficacy.


Assuntos
Mastite Bovina , Infecções Estafilocócicas , Vacinação , Animais , Bovinos , Feminino , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Mastite Bovina/imunologia , Mastite Bovina/prevenção & controle , Leite , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/veterinária , Staphylococcus aureus , Vacinas Bacterianas/imunologia , Vacinação/veterinária
8.
Science ; 378(6619): 475-476, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378974

RESUMO

The tissue environment influences astrocyte form and function in health and disease.


Assuntos
Astrócitos , Sistema Nervoso Central , Astrócitos/citologia , Astrócitos/fisiologia , Animais , Camundongos , Especificidade de Órgãos
9.
Science ; 378(6619): eadc9020, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378959

RESUMO

Astrocytes, a type of glia, are abundant and morphologically complex cells. Here, we report astrocyte molecular profiles, diversity, and morphology across the mouse central nervous system (CNS). We identified shared and region-specific astrocytic genes and functions and explored the cellular origins of their regional diversity. We identified gene networks correlated with astrocyte morphology, several of which unexpectedly contained Alzheimer's disease (AD) risk genes. CRISPR/Cas9-mediated reduction of candidate genes reduced astrocyte morphological complexity and resulted in cognitive deficits. The same genes were down-regulated in human AD, in an AD mouse model that displayed reduced astrocyte morphology, and in other human brain disorders. We thus provide comprehensive molecular data on astrocyte diversity and mechanisms across the CNS and on the molecular basis of astrocyte morphology in health and disease.


Assuntos
Doença de Alzheimer , Astrócitos , Sistema Nervoso Central , Transcriptoma , Animais , Humanos , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Astrócitos/classificação , Astrócitos/metabolismo , Astrócitos/ultraestrutura , Modelos Animais de Doenças , Sistema Nervoso Central/citologia , Sistema Nervoso Central/metabolismo
10.
Acta Ophthalmol ; 100 Suppl 273: 3-59, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36343937

RESUMO

Age-related macular degeneration (AMD) is an eye disease, which causes impaired vision that can lead to blindness. The incidence of AMD increases with age. Retinal pigment epithelial (RPE) cells maintain retinal homeostasis and support the functionality of photoreceptors. In the pathogenesis of AMD, the degeneration of the RPE cells precedes photoreceptor cell death. RPE cells are susceptible to oxidative stress, and chronic inflammation involving nucleotide-binding domain, leucine-rich repeat and pyrin domain 3 (NLRP3) inflammasome activation and impaired autophagy are challenges faced by aged RPE cells in AMD. There are two types of AMD, dry (85-90%) and wet (10-15%) disease forms. Choroidal neovascularization is typical for wet AMD, and anti-vascular endothelial growth factor (anti-VEGF) injections are used to prevent the progression of the disease but there is no curative treatment. There is no cure for the dry disease form, but antioxidants have been proposed as a potential treatment option. Ageing is the most important risk factor of AMD, and tobacco smoke is the most important environmental risk factor that can be controlled. Hydroquinone is a cytotoxic, immunotoxic, carcinogenic and pro-oxidative component of tobacco smoke. The aim of this PhD thesis was to study hydroquinone-induced oxidative stress and NLRP3 inflammasome activation in human RPE cells (ARPE-19 cells). An age-related eye disease study (AREDS) formulation (incl. omega-3 fatty acids, vitamin C and E, copper, zinc, lutein and zeaxanthin), which is clinically investigated p.o. dosing combination of dietary supplements for AMD patients, has been evaluated as a possible treatment and restraining option for AMD. Resvega (4.1.1, Table 2) is a similar kind of product to AREDS with added resveratrol, and many of the components incorporated within Resvega can be considered as belonging to the normal antioxidative defence system of the retina. Another aim was to evaluate the effects of Resvega on hydroquinone-induced oxidative stress or NLRP3 inflammasome activation induced by impaired protein clearance. The results of this study reveal that hydroquinone elevated the activity of NADPH oxidase which subsequently mediated the production of reactive oxygen species (ROS) and predisposed RPE cells to degeneration by reducing levels of vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF). Hydroquinone induced an NLRP3-independent IL-18 release and NLRP3 accumulation inside the IL-1α-primed cells. Resvega treatment reduced the extent of hydroquinone-induced ROS production and NLRP3 inflammasome activation evoked by impaired protein clearance. Thus, Resvega alleviated hydroquinone- and impaired protein clearance-induced stress in human RPE cells, but more studies are needed, for example, to reveal the most optimal route of administration for targeting the cells in the retina, since both oxidative stress and NLRP3 inflammasome activation are important contributors to the development of AMD and represent significant treatment targets.


Assuntos
Células Epiteliais , Estresse Oxidativo , Poluição por Fumaça de Tabaco , Degeneração Macular Exsudativa , Humanos , Antioxidantes/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Hidroquinonas , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/patologia , Poluição por Fumaça de Tabaco/efeitos adversos , Degeneração Macular Exsudativa/metabolismo
11.
Cells ; 11(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36359747

RESUMO

Hereditary spastic paraplegia (HSP) is a heterogeneous group of genetic neurodegenerative disorders, characterized by progressive lower limb spasticity and weakness resulting from retrograde axonal degeneration of motor neurons (MNs). Here, we generated in vitro human neuromuscular junctions (NMJs) from five HSP patient-specific induced pluripotent stem cell (hiPSC) lines, by means of microfluidic strategy, to model disease-relevant neuropathologic processes. The strength of our NMJ model lies in the generation of lower MNs and myotubes from autologous hiPSC origin, maintaining the genetic background of the HSP patient donors in both cell types and in the cellular organization due to the microfluidic devices. Three patients characterized by a mutation in the SPG3a gene, encoding the ATLASTIN GTPase 1 protein, and two patients with a mutation in the SPG4 gene, encoding the SPASTIN protein, were included in this study. Differentiation of the HSP-derived lines gave rise to lower MNs that could recapitulate pathological hallmarks, such as axonal swellings with accumulation of Acetyl-α-TUBULIN and reduction of SPASTIN levels. Furthermore, NMJs from HSP-derived lines were lower in number and in contact point complexity, denoting an impaired NMJ profile, also confirmed by some alterations in genes encoding for proteins associated with microtubules and responsible for axonal transport. Considering the complexity of HSP, these patient-derived neuronal and skeletal muscle cell co-cultures offer unique tools to study the pathologic mechanisms and explore novel treatment options for rescuing axonal defects and diverse cellular processes, including membrane trafficking, intracellular motility and protein degradation in HSP.


Assuntos
Células-Tronco Pluripotentes Induzidas , Junção Neuromuscular , Paraplegia Espástica Hereditária , Humanos , Adenosina Trifosfatases/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/patologia , Junção Neuromuscular/citologia , Junção Neuromuscular/patologia , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/patologia , Espastina/metabolismo
12.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362023

RESUMO

Tumor-associated macrophages (TAMs) and abnormalities in cancer cells affect cancer progression and response to therapy. TAMs are a major component of the tumor microenvironment (TME) in breast cancer, with their invasion affecting clinical outcomes. Programmed death-ligand 1 (PD-L1), a target of immune checkpoint inhibitors, acts as a suppressive signal for the surrounding immune system; however, its expression and effect on TAMs and the clinical outcome in breast cancer are unknown. In this study, we used high-throughput multiple immunohistochemistry to spatially and quantitatively analyze TAMs. We subjected 81 breast cancer specimens to immunostaining for CD68, CD163, PD-1, PD-L1, CD20, and pan-CK. In both stromal and intratumoral areas, the triple-negative subtype had significantly more CD68/CD163, CD68/PD-L1, and CD163/PD-L1 double-positive cells than the estrogen receptor (ER)/progesterone receptor (PR) subtype. Interestingly, a higher number of CD68+/PD-L1+/CK-/CD163- TAMs in the intratumoral area was correlated with a favorable recurrence rate (p = 0.048). These findings indicated that the specific subpopulation and localization of TAMs in the TME affect clinical outcomes in breast cancer.


Assuntos
Antígeno B7-H1 , Neoplasias de Mama Triplo Negativas , Macrófagos Associados a Tumor , Humanos , Antígeno B7-H1/metabolismo , Macrófagos/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral , Macrófagos Associados a Tumor/citologia , Biomarcadores Tumorais
13.
Cells ; 11(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36359794

RESUMO

Regenerative endodontic treatment based on tissue engineering has recently gained interest in contemporary restorative dentistry. However, low survival rates and poor potential differentiation of stem cells could undermine the success rate of pulp regenerative therapy. Human gingival fibroblast-conditioned medium (hGF-CM) has been considered a potential therapy for tissue regeneration due to its stability in maintaining multiple factors essential for tissue regeneration compared to live cell transplantation. This study aimed to investigate the potency of hGF-CM on stem cells from human dental pulp (DPSC) in pulp regeneration. A series of experiments confirmed that hGF-CM contributes to a significant increase in proliferation, migration capability, and cell viability of DPSC after H2O2 exposure. Moreover, it has been proved to facilitate the odontogenic differentiation of DPSC via qRT-PCR, ALP (alkaline phosphatase), and ARS (Alizarin Red S) staining. It has been discovered that such highly upregulated odontogenesis is related to certain types of ECM proteins (collagen and laminin) from hGF-CM via proteomics. In addition, it is found that the ERK pathway is a key mechanism via inhibition assay based on RNA-seq result. These findings demonstrate that hGF-CM could be beneficial biomolecules for pulp regeneration.


Assuntos
Meios de Cultivo Condicionados , Polpa Dentária , Peróxido de Hidrogênio , Engenharia Tecidual , Humanos , Fosfatase Alcalina/metabolismo , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/metabolismo , Fibroblastos/metabolismo , Regeneração , Gengiva/citologia , Gengiva/metabolismo , Engenharia Tecidual/métodos
14.
Cells ; 11(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36359814

RESUMO

Low back pain is a clinically highly relevant musculoskeletal burden and is associated with inflammatory as well as degenerative processes of the intervertebral disc. However, the pathophysiology and cellular pathways contributing to this devastating condition are still poorly understood. Based on previous evidence, we hypothesize that tissue renin-angiotensin system (tRAS) components, including the SARS-CoV-2 entry receptor angiotensin-converting enzyme 2 (ACE2), are present in human nucleus pulposus (NP) cells and associated with inflammatory and degenerative processes. Experiments were performed with NP cells from four human donors. The existence of angiotensin II, angiotensin II type 1 receptor (AGTR1), AGTR2, MAS-receptor (MasR), and ACE2 in human NP cells was validated with immunofluorescent staining and gene expression analysis. Hereafter, the cell viability was assessed after adding agonists and antagonists of the target receptors as well as angiotensin II in different concentrations for up to 48 h of exposure. A TNF-α-induced inflammatory in vitro model was employed to assess the impact of angiotensin II addition and the stimulation or inhibition of the tRAS receptors on inflammation, tissue remodeling, expression of tRAS markers, and the release of nitric oxide (NO) into the medium. Furthermore, protein levels of IL-6, IL-8, IL-10, and intracellular as well as secreted angiotensin II were assessed after exposing the cells to the substances, and inducible nitric oxide synthase (iNOS) levels were evaluated by utilizing Western blot. The existence of tRAS receptors and angiotensin II were validated in human NP cells. The addition of angiotensin II only showed a mild impact on gene expression markers. However, there was a significant increase in NO secreted by the cells. The gene expression ratios of pro-inflammatory/anti-inflammatory cytokines IL-6/IL-10, IL-8/IL-10, and TNF-α/IL-10 were positively correlated with the AGTR1/AGTR2 and AGTR1/MAS1 ratios, respectively. The stimulation of the AGTR2 MAS-receptor and the inhibition of the AGTR1 receptor revealed beneficial effects on the gene expression of inflammatory and tissue remodeling markers. This finding was also present at the protein level. The current data showed that tRAS components are expressed in human NP cells and are associated with inflammatory and degenerative processes. Further characterization of the associated pathways is warranted. The findings indicate that tRAS modulation might be a novel therapeutic approach to intervertebral disc disease.


Assuntos
Núcleo Pulposo , Sistema Renina-Angiotensina , Humanos , Angiotensina II/metabolismo , Enzima de Conversão de Angiotensina 2 , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Núcleo Pulposo/citologia , Núcleo Pulposo/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Biochem Biophys Res Commun ; 636(Pt 2): 79-86, 2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36368158

RESUMO

During mammalian retinal development, the differentiation of multipotent progenitors depends on the coordinated action of a variety of intrinsic factors including non-coding RNAs (ncRNAs). To date, many small open reading frames have been identified in ncRNAs to encode micropeptides that function in diverse biological processes; however, it remains unclear whether they have a role in retinal development. Here we report that the 47-amino acid (AA) mitochondrial micropeptide Stmp1 encoded by the lncRNA 1810058I24Rik is involved in retinal differentiation. As the major protein product of 1810058I24Rik, Stmp1 promotes the differentiation of bipolar, amacrine and Müller cells as 1810058I24Rik does when overexpressed in neonatal murine retinas. Moreover, we have identified the 15-AA N-terminus of Stmp1 as its mitochondrion-targeting sequence as well as 5 conserved AA residues that affect protein stability and/or retinal cell differentiation. Together, our data reveal several novel characteristics of Stmp1 and uncover a role for Stmp1 in retinal cell differentiation perhaps through regulating mitochondrial function.


Assuntos
Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intracelular , Mitocôndrias , Proteínas Mitocondriais , Retina , Animais , Camundongos , Células Ependimogliais/citologia , Mitocôndrias/metabolismo , Neurônios/citologia , Retina/citologia , RNA não Traduzido/genética , Proteínas Mitocondriais/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia
16.
Science ; 378(6619): eabm8797, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378956

RESUMO

Genetically encoded fluorescent voltage indicators are ideally suited to reveal the millisecond-scale interactions among and between targeted cell populations. However, current indicators lack the requisite sensitivity for in vivo multipopulation imaging. We describe next-generation green and red voltage sensors, Ace-mNeon2 and VARNAM2, and their reverse response-polarity variants pAce and pAceR. Our indicators enable 0.4- to 1-kilohertz voltage recordings from >50 spiking neurons per field of view in awake mice and ~30-minute continuous imaging in flies. Using dual-polarity multiplexed imaging, we uncovered brain state-dependent antagonism between neocortical somatostatin-expressing (SST+) and vasoactive intestinal peptide-expressing (VIP+) interneurons and contributions to hippocampal field potentials from cell ensembles with distinct axonal projections. By combining three mutually compatible indicators, we performed simultaneous triple-population imaging. These approaches will empower investigations of the dynamic interplay between neuronal subclasses at single-spike resolution.


Assuntos
Potenciais de Ação , Hipocampo , Imagem Molecular , Neurônios , Córtex Visual , Animais , Camundongos , Potenciais de Ação/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Interneurônios/fisiologia , Neurônios/classificação , Neurônios/fisiologia , Peptídeo Intestinal Vasoativo/metabolismo , Imagem Molecular/métodos , Rodopsina/química , Rodopsina/genética , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Córtex Visual/citologia , Córtex Visual/fisiologia , Fluorescência , Medições Luminescentes
18.
Nature ; 610(7931): 319-326, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36224417

RESUMO

Self-organizing neural organoids represent a promising in vitro platform with which to model human development and disease1-5. However, organoids lack the connectivity that exists in vivo, which limits maturation and makes integration with other circuits that control behaviour impossible. Here we show that human stem cell-derived cortical organoids transplanted into the somatosensory cortex of newborn athymic rats develop mature cell types that integrate into sensory and motivation-related circuits. MRI reveals post-transplantation organoid growth across multiple stem cell lines and animals, whereas single-nucleus profiling shows progression of corticogenesis and the emergence of activity-dependent transcriptional programs. Indeed, transplanted cortical neurons display more complex morphological, synaptic and intrinsic membrane properties than their in vitro counterparts, which enables the discovery of defects in neurons derived from individuals with Timothy syndrome. Anatomical and functional tracings show that transplanted organoids receive thalamocortical and corticocortical inputs, and in vivo recordings of neural activity demonstrate that these inputs can produce sensory responses in human cells. Finally, cortical organoids extend axons throughout the rat brain and their optogenetic activation can drive reward-seeking behaviour. Thus, transplanted human cortical neurons mature and engage host circuits that control behaviour. We anticipate that this approach will be useful for detecting circuit-level phenotypes in patient-derived cells that cannot otherwise be uncovered.


Assuntos
Vias Neurais , Organoides , Animais , Animais Recém-Nascidos , Transtorno Autístico , Humanos , Síndrome do QT Longo , Motivação , Neurônios/fisiologia , Optogenética , Organoides/citologia , Organoides/inervação , Organoides/transplante , Ratos , Recompensa , Córtex Somatossensorial/citologia , Córtex Somatossensorial/fisiologia , Células-Tronco/citologia , Sindactilia
19.
Science ; 378(6616): 192-201, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36227993

RESUMO

We engineered an ultrasensitive reporter of p16INK4a, a biomarker of cellular senescence. Our reporter detected p16INK4a-expressing fibroblasts with certain senescent characteristics that appeared shortly after birth in the basement membrane adjacent to epithelial stem cells in the lung. Furthermore, these p16INK4a+ fibroblasts had enhanced capacity to sense tissue inflammation and respond through their increased secretory capacity to promote epithelial regeneration. In addition, p16INK4a expression was required in fibroblasts to enhance epithelial regeneration. This study highlights a role for p16INK4a+ fibroblasts as tissue-resident sentinels in the stem cell niche that monitor barrier integrity and rapidly respond to inflammation to promote tissue regeneration.


Assuntos
Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina , Células Epiteliais , Fibroblastos , Genes Reporter , Pulmão , Regeneração , Nicho de Células-Tronco , Humanos , Membrana Basal/citologia , Membrana Basal/fisiologia , Biomarcadores/metabolismo , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Fibroblastos/metabolismo , Inflamação/metabolismo , Pulmão/patologia , Pulmão/fisiologia , Células Epiteliais/fisiologia , Nicho de Células-Tronco/fisiologia
20.
Iran J Immunol ; 19(3): 232-242, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36190378

RESUMO

BACKGROUND: Sepsis is a serious condition with a high mortality rate, and septic patients often have organ dysfunction, low tissue perfusion and hypoxia, lactic acidosis, oliguria, or functional brain changes. OBJECTIVE: To observe the number and the function of Vδ1T cells in peripheral blood of septic patients, to analyze the clinical significance of detecting Vδ1T cells, and to clarify the correlation of their presence with the prognosis of sepsis. METHODS: The basic data of the septic patients were recorded at admission. The immunosuppressive function-related molecules on the surface of Vδ1T cells were detected, and the immunosuppressive function of Vδ1T cells was also evaluated. RESULTS: Compared with the healthy controls, the proportion of Vδ1T cells in the blood of septic patients significantly decreased (P<0.01). The proportion of Vδ1T cells in septic patients correlated with the patients' condition (P<0.05). The expression of glucocorticoid-induced tumor necrosis factor receptor (GITR), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surface of Vδ1T cells in the blood of septic patients significantly increased (P<0.01). The increase of Vδ1T cells in septic patients had inhibitory effects on T cell proliferation and interferon (IFN)-γ secretion. These findings implied that the immunosuppression of Vδ1Tcells in the peripheral blood of septic patients was significantly higher than that of the healthy controls (P<0.01). CONCLUSION: Changes in Vδ1T cells in septic patients were closely related to the patient's condition and prognosis.


Assuntos
Sepse , Subpopulações de Linfócitos T , Antígeno CTLA-4 , Glucocorticoides , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Interferons , Prognóstico , Sepse/diagnóstico , Subpopulações de Linfócitos T/citologia
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