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1.
Nature ; 602(7897): 523-528, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35140398

RESUMEN

A protein backbone structure is designable if a substantial number of amino acid sequences exist that autonomously fold into it1,2. It has been suggested that the designability of backbones is governed mainly by side chain-independent or side chain type-insensitive molecular interactions3-5, indicating an approach for designing new backbones (ready for amino acid selection) based on continuous sampling and optimization of the backbone-centred energy surface. However, a sufficiently comprehensive and precise energy function has yet to be established for this purpose. Here we show that this goal is met by a statistical model named SCUBA (for Side Chain-Unknown Backbone Arrangement) that uses neural network-form energy terms. These terms are learned with a two-step approach that comprises kernel density estimation followed by neural network training and can analytically represent multidimensional, high-order correlations in known protein structures. We report the crystal structures of nine de novo proteins whose backbones were designed to high precision using SCUBA, four of which have novel, non-natural overall architectures. By eschewing use of fragments from existing protein structures, SCUBA-driven structure design facilitates far-reaching exploration of the designable backbone space, thus extending the novelty and diversity of the proteins amenable to de novo design.


Asunto(s)
Redes Neurales de la Computación , Proteínas , Secuencia de Aminoácidos , Modelos Moleculares , Conformación Proteica , Proteínas/química
2.
J Immunol ; 212(11): 1714-1721, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598411

RESUMEN

Ag-specific effector CD4+ T cells play a crucial role in defending against exogenous pathogens. However, the mechanisms governing the differentiation and function of IFN-γ-producing effector CD4+ Th1 cells in immune responses remain largely unknown. In this study, we elucidated the pivotal role of zinc finger protein 335 (Zfp335) in regulating effector Th1 cell differentiation and survival during acute bacterial infection. Mice with Zfp335 knockout in OT-II cells exhibited impaired Ag-specific CD4+ T cell expansion accompanied by a significant reduction in resistance to Listeria infection. Furthermore, Zfp335 deficiency restricted the effector CD4+ Th1 cell population and compromised their survival upon Listeria challenge. The expression of T-bet and IFN-γ was accordingly decreased in Zfp335-deficient Th1 cells. Mechanistically, Zfp335 directly bound to the promoter region of the Lmna gene and regulated its expression. Overexpression of Lmna was able to rescue the survival and function of Zfp335-deficient effector Th1 cells. Therefore, our study provides novel insights into the mechanisms governing effector Th1 cell differentiation and survival during acute infection.


Asunto(s)
Diferenciación Celular , Proteínas de Unión al ADN , Lamina Tipo A , Ratones Noqueados , Células TH1 , Factores de Transcripción , Animales , Ratones , Diferenciación Celular/inmunología , Diferenciación Celular/genética , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Lamina Tipo A/genética , Listeriosis/inmunología , Ratones Endogámicos C57BL , Células TH1/inmunología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(39): e2305603120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37722056

RESUMEN

An increasing number of protein interaction domains and their targets are being found to be intrinsically disordered proteins (IDPs). The corresponding target recognition mechanisms are mostly elusive because of challenges in performing detailed structural analysis of highly dynamic IDP-IDP complexes. Here, we show that by combining recently developed computational approaches with experiments, the structure of the complex between the intrinsically disordered C-terminal domain (CTD) of protein 4.1G and its target IDP region in NuMA can be dissected at high resolution. First, we carry out systematic mutational scanning using dihydrofolate reductase-based protein complementarity analysis to identify essential interaction regions and key residues. The results are found to be highly consistent with an α/ß-type complex structure predicted by AlphaFold2 (AF2). We then design mutants based on the predicted structure using a deep learning protein sequence design method. The solved crystal structure of one mutant presents the same core structure as predicted by AF2. Further computational prediction and experimental assessment indicate that the well-defined core structure is conserved across complexes of 4.1G CTD with other potential targets. Thus, we reveal that an intrinsically disordered protein interaction domain uses an α/ß-type structure module formed through synergistic folding to recognize broad IDP targets. Moreover, we show that computational prediction and experiment can be jointly applied to segregate true IDP regions from the core structural domains of IDP-IDP complexes and to uncover the structure-dependent mechanisms of some otherwise elusive IDP-IDP interactions.


Asunto(s)
Proteínas Intrínsecamente Desordenadas , Proteínas Intrínsecamente Desordenadas/genética , Furilfuramida , Secuencia de Aminoácidos , Mutación , Dominios y Motivos de Interacción de Proteínas
4.
Blood ; 141(12): 1474-1488, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36574342

RESUMEN

Disorders of the ubiquitin-proteasome system (UPS) are known to influence the incidence and mortality of various diseases. It remains largely unknown whether and how the UPS affects the onset and progression of acute graft-verus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study demonstrated that the deubiquitinase OTUD1 is an essential regulator of aGVHD. Activation of CD4+ T cells after allo-HSCT, elevated the protein levels of OTUD1, which in turn interacted with the Notch2-ICD (NICD) to cleave the ubiquitin of NICD at the K1770 site, thereby inducing NICD protein accumulations in T cells. OTUD1-driven NICD signaling promoted the differentiation and functions of Th1 and Th17 cells and amplified the cascade of aGVHD. Moreover, by screening a FDA-approved drugs library the study identified dapagliflozin as an inhibitor targeting the OTUD1/NICD axis. Dapagliflozin administration significantly prolonged the survival of aGVHD mice. This study characterized a previously unknown role of OTUD1 in T cell-mediated allogeneic responses and provided a promising therapeutic strategy to target OTUD1 for the alleviation of aGVHD.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Animales , Ratones , Enfermedad Aguda , Linfocitos T CD4-Positivos/metabolismo , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ubiquitinas
5.
FASEB J ; 38(8): e23631, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38661062

RESUMEN

Recurrent miscarriage (RM) is related to the dysfunction of extravillous trophoblast cells (EVTs), but the comprehensive mechanisms remain largely unexplored. We analyzed single-cell RNA sequencing (scRNA-seq), bulk RNA sequencing and microarray datasets obtained from Gene Expression Omnibus (GEO) database to explore the hub genes in the mechanisms of RM. We identified 1724 differentially expressed genes (DEGs) in EVTs from the RM, and they were all expressed along the trajectory of EVTs. These DEGs were associated with hypoxia and glucose metabolism. Single-cell Regulatory Network Inference and Clustering (SCENIC) analysis revealed that E2F transcription factor (E2F) 8 (E2F8) was a key transcription factor for these DEGs. And the expression of ENO1 can be positively regulated by E2F8 via RNA sequencing analysis. Subsequently, we performed immunofluorescence assay (IF), plasmid transfection, western blotting, chromatin immunoprecipitation (ChIP), real-time quantitative polymerase chain reaction (qRT-PCR), and transwell assays for validation experiments. We found that the expression of alpha-Enolase 1 (ENO1) was lower in the placentas of RM. Importantly, E2F8 can transcriptionally regulate the expression of ENO1 to promote the invasion of trophoblast cells by inhibiting secreted frizzled-related protein 1/4 (SFRP1/4) to activate Wnt signaling pathway. Our results suggest that ENO1 can promote trophoblast invasion via an E2F8-dependent manner, highlighting a potential novel target for the physiological mechanisms of RM.


Asunto(s)
Aborto Habitual , Proteínas de Unión al ADN , Proteínas Represoras , Trofoblastos , Adulto , Femenino , Humanos , Embarazo , Aborto Habitual/metabolismo , Aborto Habitual/genética , Aborto Habitual/patología , Movimiento Celular , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Fosfopiruvato Hidratasa/metabolismo , Fosfopiruvato Hidratasa/genética , Trofoblastos/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Represoras/metabolismo
6.
BMC Immunol ; 25(1): 12, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326745

RESUMEN

BACKGROUND: Imbalanced immune responses are involved in developing preeclampsia (PE). We wish to explore the expression and potential changes of immune checkpoint molecules TIGIT, CD226 and CD155 in PE patients. METHODS: The expression of the immune checkpoint molecules TIGIT, CD226 and CD155 in different lymphocyte subpopulations was determined by flow cytometry in 24 patients with PE and compared to 24 healthy pregnant women of the same gestational age as the controls.​Serum CD155 was detected by ELISA in the patients with PE compared to controls. RESULTS: The percentages of CD4+ and CD8+ T lymphocytes in the peripheral blood of PE patients were not significantly different from those of the controls, whereas the regulatory T cells (Tregs) in PE patients were significantly lower than those in controls (6.43 ± 1.77% vs. 7.48 ± 1.71%, P = 0.0420). The expression of TIGIT and CD226 showed different percentages on CD4+ T cells, CD8+ T cells and Treg cells. However, the difference in the percentages of TIGIT, CD226 on these T cells between the two groups was not statistically significant. The level of CD155 in peripheral serum of PE patients was 6.64 ± 1.79 ng/ml, which was not significantly different from that in the control group 5.61 ± 1.77 ng/ml, P = 0.0505. The present results demonstrate that TIGIT, CD226 and CD155 are not present at altered immune conditions in the peripheral blood of patients with PE, compared with normal pregnant women. CONCLUSION: The immune checkpoint molecules TIGIT, CD226 and CD155 are not abnormally expressed in PE patients.


Asunto(s)
Linfocitos T CD8-positivos , Preeclampsia , Humanos , Embarazo , Femenino , Proteínas de Punto de Control Inmunitario/metabolismo , Preeclampsia/metabolismo , Antígenos de Diferenciación de Linfocitos T/metabolismo , Receptores Inmunológicos/metabolismo
7.
Plant Biotechnol J ; 22(7): 1848-1866, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38391124

RESUMEN

Although the regulatory mechanisms of dark and light-induced plant morphogenesis have been broadly investigated, the biological process in peanuts has not been systematically explored on single-cell resolution. Herein, 10 cell clusters were characterized using scRNA-seq-identified marker genes, based on 13 409 and 11 296 single cells from 1-week-old peanut seedling leaves grown under dark and light conditions. 6104 genes and 50 transcription factors (TFs) displayed significant expression patterns in distinct cell clusters, which provided gene resources for profiling dark/light-induced candidate genes. Further pseudo-time trajectory and cell cycle evidence supported that dark repressed the cell division and perturbed normal cell cycle, especially the PORA abundances correlated with 11 TFs highly enriched in mesophyll to restrict the chlorophyllide synthesis. Additionally, light repressed the epidermis cell developmental trajectory extending by inhibiting the growth hormone pathway, and 21 TFs probably contributed to the different genes transcriptional dynamic. Eventually, peanut AHL17 was identified from the profile of differentially expressed TFs, which encoded protein located in the nucleus promoted leaf epidermal cell enlargement when ectopically overexpressed in Arabidopsis through the regulatory phytohormone pathway. Overall, our study presents the different gene atlases in peanut etiolated and green seedlings, providing novel biological insights to elucidate light-induced leaf cell development at the single-cell level.


Asunto(s)
Arachis , Regulación de la Expresión Génica de las Plantas , Luz , Hojas de la Planta , Plantones , Arachis/genética , Arachis/metabolismo , Arachis/crecimiento & desarrollo , Arachis/efectos de la radiación , Hojas de la Planta/genética , Hojas de la Planta/efectos de la radiación , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Plantones/genética , Plantones/efectos de la radiación , Plantones/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/efectos de la radiación , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Oscuridad , Perfilación de la Expresión Génica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análisis de Expresión Génica de una Sola Célula
8.
Ann Neurol ; 94(1): 27-40, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36897120

RESUMEN

OBJECTIVE: In Alzheimer's disease, hyperphosphorylated tau is associated with formation of insoluble paired helical filaments that aggregate as neurofibrillary tau tangles and are associated with neuronal loss and cognitive symptoms. Dual orexin receptor antagonists decrease soluble amyloid-ß levels and amyloid plaques in mouse models overexpressing amyloid-ß, but have not been reported to affect tau phosphorylation. In this randomized controlled trial, we tested the acute effect of suvorexant, a dual orexin receptor antagonist, on amyloid-ß, tau, and phospho-tau. METHODS: Thirty-eight cognitively unimpaired participants aged 45 to 65 years were randomized to placebo (N = 13), suvorexant 10 mg (N = 13), and suvorexant 20 mg (N = 12). Six milliliters of cerebrospinal fluid were collected via an indwelling lumbar catheter every 2 hours for 36 hours starting at 20:00. Participants received placebo or suvorexant at 21:00. All samples were processed and measured for multiple forms of amyloid-ß, tau, and phospho-tau via immunoprecipitation and liquid chromatography-mass spectrometry. RESULTS: The ratio of phosphorylated-tau-threonine-181 to unphosphorylated-tau-threonine-181, a measure of phosphorylation at this tau phosphosite, decreased ~10% to 15% in participants treated with suvorexant 20 mg compared to placebo. However, phosphorylation at tau-serine-202 and tau-threonine-217 were not decreased by suvorexant. Suvorexant decreased amyloid-ß ~10% to 20% compared to placebo starting 5 hours after drug administration. INTERPRETATION: In this study, suvorexant acutely decreased tau phosphorylation and amyloid-ß concentrations in the central nervous system. Suvorexant is approved by the US Food and Drug Administration to treatment insomnia and may have potential as a repurposed drug for the prevention of Alzheimer's disease, however, future studies with chronic treatment are needed. ANN NEUROL 2023;94:27-40.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Animales , Humanos , Enfermedad de Alzheimer/diagnóstico , Fosforilación , Proteínas tau/metabolismo , Péptidos beta-Amiloides/metabolismo , Sistema Nervioso Central/metabolismo , Antagonistas de los Receptores de Orexina/farmacología , Antagonistas de los Receptores de Orexina/uso terapéutico
9.
Opt Express ; 32(4): 6791-6799, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439376

RESUMEN

Realtime spectroscopy access to ultrafast fiber lasers provides new opportunities for exploring complex soliton interaction dynamics. In this study, we employ a time-stretch technique that enables real-time access to both spectral and temporal dynamics, revealing rich nonlinear processes in asynchronous dual wavelength mode-locked pulses in an ultrafast fiber laser. Due to the different group velocities of the two wavelengths, the mode-locked solitons centered at different wavelengths periodically collide with each other. We recorded the entire process of soliton establishment, stabilization, and disappearance, shedding light on the mystery of stable transmission of dual-wavelength mode-locked pulses. These processes were observed for the first time in an ultrafast fiber laser, and the experimental evidence provides important insights into the understanding of nonlinear dynamics in fiber lasers, as well as the potential for improving laser performance for application in dual-comb spectroscopy.

10.
BMC Cancer ; 24(1): 598, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755535

RESUMEN

BACKGROUND: Results regarding whether it is essential to incorporate genetic variants into risk prediction models for esophageal cancer (EC) are inconsistent due to the different genetic backgrounds of the populations studied. We aimed to identify single-nucleotide polymorphisms (SNPs) associated with EC among the Chinese population and to evaluate the performance of genetic and non-genetic factors in a risk model for developing EC. METHODS: A meta-analysis was performed to systematically identify potential SNPs, which were further verified by a case-control study. Three risk models were developed: a genetic model with weighted genetic risk score (wGRS) based on promising SNPs, a non-genetic model with environmental risk factors, and a combined model including both genetic and non-genetic factors. The discrimination ability of the models was compared using the area under the receiver operating characteristic curve (AUC) and the net reclassification index (NRI). The Akaike information criterion (AIC) and Bayesian information criterion (BIC) were used to assess the goodness-of-fit of the models. RESULTS: Five promising SNPs were ultimately utilized to calculate the wGRS. Individuals in the highest quartile of the wGRS had a 4.93-fold (95% confidence interval [CI]: 2.59 to 9.38) increased risk of EC compared with those in the lowest quartile. The genetic or non-genetic model identified EC patients with AUCs ranging from 0.618 to 0.650. The combined model had an AUC of 0.707 (95% CI: 0.669 to 0.743) and was the best-fitting model (AIC = 750.55, BIC = 759.34). The NRI improved when the wGRS was added to the risk model with non-genetic factors only (NRI = 0.082, P = 0.037). CONCLUSIONS: Among the three risk models for EC, the combined model showed optimal predictive performance and can help to identify individuals at risk of EC for tailored preventive measures.


Asunto(s)
Pueblo Asiatico , Neoplasias Esofágicas , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Humanos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/epidemiología , Factores de Riesgo , Estudios de Casos y Controles , China/epidemiología , Pueblo Asiatico/genética , Femenino , Masculino , Persona de Mediana Edad , Medición de Riesgo/métodos , Curva ROC , Interacción Gen-Ambiente , Pueblos del Este de Asia
11.
BMC Cancer ; 24(1): 482, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627648

RESUMEN

BACKGROUND: Therapies for metastatic castration-resistant prostate cancer (mCRPC) include targeting the androgen receptor (AR) with androgen receptor inhibitors (ARIs) and prostate-specific membrane antigen (PSMA). Having the ability to detect AR, AR splice variant 7 (AR-V7), or PSMA in circulating tumor cells (CTCs) or circulating exosomal cell-free RNA (cfRNA) could be helpful to guide selection of the appropriate therapy for each individual patient. The Vortex Biosciences VTX-1 system is a label-free CTC isolation system that enables the detection of the expression of multiple genes in both CTCs and exosomal cfRNA from the same blood sample in patients with mCRPC. Detection of both AR-V7 and PSMA gene expression in both CTCs and cfRNA simultaneously has not yet been reported. METHODS: To characterize the combined VTX-1-AdnaDetect workflow, 22Rv1 cancer cells were spiked into blood from healthy donors and processed with the VTX-1 to mimic patient samples and assess performances (capture efficiency, purity, AR and AR-V7 expression). Then, we collected 19 blood samples from 16 patients with mCRPC and therapeutic resistance to androgen receptor inhibitors (ARIs). Plasma was separated and the plasma-depleted blood was processed further with the VTX-1 to collect CTCs. Both plasma exosomal cfRNA and CTCs were subsequently analyzed for AR, AR-V7, PSMA, and prostate-specific antigen (PSA) mRNA expression using the AdnaTest ProstateCancerPanel AR-V7 assay. RESULTS: AR-V7 expression could be detected in 22Rv1 cells spiked into blood from healthy volunteers as well as in CTCs and plasma-derived exosomal cfRNA from patients with mCRPC by processing blood with the VTX-1 CTC isolation system followed by the AdnaTest ProstateCancerPanel AR-V7 assay. 94.7% of patient blood samples (18/19) had detectable AR expression in either CTCs or exosomal cfRNA (16 in CTCs, 12 in cfRNA). 15.8% of the 19 patient blood samples (3/19) were found to have AR-V7-positive (AR-V7+) CTCs, one of which was also AR-V7+ in the exosomal cfRNA analysis. 42.1% of patient blood samples (8/19) were found to be PSMA positive (PSMA+): 26.3% (5/19) were PSMA+ in the CTC analysis and 31.6% (6/19) were PSMA+ in the exosomal cfRNA analysis. Of those 8 PSMA+ samples, 2 had detectable PSMA only in CTCs, and 3 had detectable PSMA only in exosomal cfRNA. CONCLUSION: VTX-1 enables isolation of CTCs and plasma exosomes from a single blood draw and can be used for detecting AR-V7 and PSMA mRNA in both CTCs and cfRNA in patients with mCRPC and resistance to ARIs. This technology facilitates combining RNA measurements in CTCs and exosomal cfRNA for future studies to develop potentially clinically relevant cancer biomarker detection in blood.


Asunto(s)
Ácidos Nucleicos Libres de Células , Exosomas , Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Antagonistas de Receptores Androgénicos/farmacología , Antagonistas de Receptores Androgénicos/uso terapéutico , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Ácidos Nucleicos Libres de Células/metabolismo , Exosomas/genética , Exosomas/metabolismo , Células Neoplásicas Circulantes/patología , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Isoformas de Proteínas/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , ARN Mensajero/genética
12.
FASEB J ; 37(3): e22779, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36723798

RESUMEN

Preeclampsia is a gestational disease characterized by two major pathological changes-shallow trophoblast invasion and impaired spiral artery remodeling. Atrial natriuretic peptide (ANP) is a kind of peptide hormone that regulates blood pressure, while the lack of active ANP participates in preeclampsia pathogenesis. However, the underlying mechanism of how ANP modulates trophoblasts function remains unclarified. Here, we performed isobaric tags for relative and absolute quantification (iTRAQ) in ANP-treated HTR-8/SVneo cells and identified Protein Kinase 3 (PKN3) as the downstream factor of ANP, which was downregulated in preeclamptic placenta. Chromatin immunoprecipitation analysis and luciferase assays showed that NFYA was one of the transcription factors for the PKN3 promoter, which was also regulated by ANP treatment in HTR-8/SVneo cells. Transmission electron microscopy and Western Blotting in HTR-8/SVneo cells indicated that ANP inhibited autophagy via AMPK-mTORC1 signaling, while excess autophagy was observed in preeclamptic placenta. The increased expression of PKN3 and enhanced cell invasion ability in HTR-8/SVneo cells induced by ANP could be abolished by autophagy activation or transfection with PKN3 shRNA or NFYA shRNA or NPR-A shRNA via regulating the invasion-related genes and the epithelial mesenchymal transition molecules. Our results demonstrated that ANP could enhance trophoblast invasion by upregulating PKN3 via NFYA promotion through autophagy inhibition in an AMPK/mTORC1 signaling-dependent manner.


Asunto(s)
Preeclampsia , Femenino , Humanos , Embarazo , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia , Línea Celular , Movimiento Celular , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Placenta/metabolismo , Preeclampsia/metabolismo , ARN Interferente Pequeño/metabolismo , Trofoblastos/metabolismo , Factor Natriurético Atrial
13.
J Immunol ; 209(5): 886-895, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35914836

RESUMEN

Memory CD8+ T cells play an essential role in providing effective and lifelong protection against pathogens. Comprehensive transcriptional and epigenetic networks are involved in modulating memory T cell development, but the molecular regulations of CD8+ memory T cell formation and long-term persistence remain largely unknown. In this study, we show that zinc finger protein 335 (Zfp335) is indispensable for CD8+ T cell memory establishment and maintenance during acute infections. Mice with Zfp335 deletion in CD8+ T cells exhibit a significant reduction of memory T cells and memory precursor cells in the contraction phase. Zfp335 deficiency in CD8+ T cells resulted in decreased expression of memory featured genes Eomes and IL-2Rß, leading to a loss of memory identity and an increase of apoptosis in response to IL-7 and IL-15. Mechanistically, Zfp335 directly binds to and regulates TCF-1, known to be critical for memory T cell development. Importantly, overexpression TCF-1 could rescue the defects in the survival of both CD8+ memory precursors and memory T cells caused by Zfp335 deficiency. Collectively, our findings reveal that Zfp335 serves as a novel transcriptional factor upstream of TCF-1 in regulating CD8+ T cell memory.


Asunto(s)
Linfocitos T CD8-positivos , Interleucina-15 , Animales , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular/genética , Regulación de la Expresión Génica , Memoria Inmunológica/genética , Interleucina-15/metabolismo , Interleucina-7/metabolismo , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción
14.
J Immunol ; 209(5): 855-863, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36130132

RESUMEN

Effector CD8+ T cells are crucial players in adaptive immunity for effective protection against invading pathogens. The regulatory mechanisms underlying CD8+ T cell effector differentiation are incompletely understood. In this study, we defined a critical role of mediator complex subunit 1 (Med1) in controlling effector CD8+ T cell differentiation and survival during acute bacterial infection. Mice with Med1-deficient CD8+ T cells exhibited significantly impaired expansion with evidently reduced killer cell lectin-like receptor G1+ terminally differentiated and Ly6c+ effector cell populations. Moreover, Med1 deficiency led to enhanced cell apoptosis and expression of multiple inhibitory receptors (programmed cell death 1, T cell Ig and mucin domain-containing-3, and T cell immunoreceptor with Ig and ITIM domains). RNA-sequencing analysis revealed that T-bet- and Zeb2-mediated transcriptional programs were impaired in Med1-deficient CD8+ T cells. Overexpression of T-bet could rescue the differentiation and survival of Med1-deficient CD8+ effector T cells. Mechanistically, the transcription factor C/EBPß promoted T-bet expression through interacting with Med1 in effector T cells. Collectively, our findings revealed a novel role of Med1 in regulating effector CD8+ T cell differentiation and survival in response to bacterial infection.


Asunto(s)
Linfocitos T CD8-positivos , Subunidad 1 del Complejo Mediador , Animales , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Diferenciación Celular , Subunidad 1 del Complejo Mediador/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Mucinas/metabolismo , ARN/metabolismo , Receptores Similares a Lectina de Células NK/metabolismo , Proteínas de Dominio T Box/metabolismo
15.
Mol Biol Rep ; 51(1): 292, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38332381

RESUMEN

BACKGROUND: Neuroinflammation contributes to both epileptogenesis and the associated neurodegeneration, so regulation of inflammatory signaling is a potential strategy for suppressing epilepsy development and pathological progression. Exosomes are enriched in microRNAs (miRNAs), considered as vital communication tools between cells, which have been proven as potential therapeutic method for neurological disease. Here, we investigated the role of miR129-5p-loaded mesenchymal stem cell (MSC)-derived exosomes in status epilepticus (SE) mice model. METHODS: Mice were divided into four groups: untreated control (CON group), kainic acid (KA)-induced SE groups (KA group), control exosome injection (KA + Exo-con group), miR129-5p-loaded exosome injection (KA + Exo-miR129-5p group). Hippocampal expression levels of miR129-5p, HMGB1, and TLR4 were compared among groups. Nissl and Fluoro-jade B staining were conducted to evaluate neuronal damage. In addition, immunofluorescence staining for IBA-1 and GFAP was performed to assess glial cell activation, and inflammatory factor content was determined by ELISA. Hippocampal neurogenesis was assessed by BrdU staining. RESULTS: The expression of HMGB1 was increased after KA-induced SE and peaking at 48 h, while hippocampal miR129-5p expression decreased in SE mice. Exo-miR129-5p injection reversed KA-induced upregulation of hippocampal HMGB1 and TLR4, alleviated neuronal damage in the hippocampal CA3, reduced IBA-1 + and GFAP + staining intensity, suppressed SE-associated increases in inflammatory factors, and decreased BrdU + cell number in dentate gyrus. CONCLUSIONS: Exosomes loaded with miR129-5p can protect neurons against SE-mediated degeneration by inhibiting the pro-inflammatory HMGB1/TLR4 signaling axis.


Asunto(s)
Exosomas , Proteína HMGB1 , MicroARNs , Estado Epiléptico , Animales , Ratones , Bromodesoxiuridina/efectos adversos , Bromodesoxiuridina/metabolismo , Exosomas/metabolismo , Hipocampo/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Ácido Kaínico/efectos adversos , Ácido Kaínico/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Enfermedades Neuroinflamatorias , Convulsiones/genética , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genética , Estado Epiléptico/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
16.
Environ Res ; 244: 117920, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38109955

RESUMEN

Endemic arsenic poisoning and fluorosis caused by primary high arsenic (As) and high fluoride (F-) groundwater have become one of the most serious environmental geological problems faced by the international society. High As and high F- groundwater exists in Neogene confined aquifers in Guide basin, with concentrations of 355 µg/L and 5.67 mg/L, respectively, and showing a co-occurrence phenomenon of As and F- in the groundwater. This poses a double threat to the health of tens of thousands of local residents. In this study, based on the systematic collection of groundwater and borehole sediment samples, analysis of hydrochemistry and isotope indexes, combined with laboratory tests, purpose of this study is to reveal the migration rule and co-enrichment mechanism of As and F- in aquifers, and finally establish a hydrogeochemical conceptual model of the enrichment process of As and F-. The main conclusions are as follows: hydrochemical type of unconfined and confined groundwater in Guide basin is Ca-Na-HCO3 and Na-Cl-HCO3 type, respectively. Main minerals in sediments are quartz and plagioclase. Concentrations of As and F- are lower in unconfined groundwater, but higher in confined groundwater, and which show a gradual increasing trend along the groundwater flow path. The mineralization of natural organic matter in confined aquifer causes iron and manganese oxide minerals containing As to dissolve gradually, which leads to the gradual release of As into groundwater. Large amount of HCO3- produced by mineralization of organic matter precipitate with Ca2+ in groundwater, resulting in reduction of Ca2+ content, promoting the dissolution of fluoride-containing minerals such as fluorite (CaF2), and continuously releasing F- into groundwater. Meanwhile, competitive adsorption reactions in confined aquifers causes more As and F- to be released from mineral surface into groundwater, which gradually migrate and accumulate along groundwater flow. Finally, it is established that a conceptual model for the formation of high As and F- groundwater in the confined aquifer of Guide basin. The research results not only help to improve our understanding of the formation and evolution of groundwater with high As and F- with similar geological background, but also provide scientific basis for rational development and utilization of groundwater, and prevention and control of chronic As and F- poisoning in local and similar areas.


Asunto(s)
Arsénico , Agua Subterránea , Contaminantes Químicos del Agua , Fluoruros , Arsénico/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Agua Subterránea/análisis , China , Minerales/análisis
17.
BMC Pregnancy Childbirth ; 24(1): 166, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408929

RESUMEN

BACKGROUND: To date, there are no clinical guidelines for dichorionic diamniotic (DCDA) twins complicated with previable premature rupture of membrane (PV-ROM) before 24 weeks of gestation. The typical management options including expectant management and/or pregnant termination, induce the risks of fetal mortality and morbidity. OBJECTIVE: To explore the feasibility selective feticide in DCDA twins complicated with PV-ROM. STUDY DESIGN: A Retrospective cohort study, enrolling 28 DCDA twins suffering from PV-ROM in a tertiary medical center from Jan 01 2012 to Jan 01 2022. The obstetric outcome was compared between selective feticide group and expectant management group. RESULTS: There were 12 cases managed expectantly and 16 underwent selective feticide. More cases suffered from oligohydramnios in expectant management group compared to selective feticide group (P = 0.008). Among 13 cases with ROM of upper sac, the mean gestational age at delivery was (33.9 ± 4.9) weeks in the selective feticide group, which was significantly higher than that in the expectant management (P = 0.038). Five fetuses (83.3%) with selective feticide delivered after 32 weeks, whereas only one (14.3%) case in expectant management group (P = 0.029). However, in the subgroup with ROM of lower sac, no significant difference of the mean gestation age at delivery between groups and none of cases delivered after 32 weeks. CONCLUSION: There was a trend towards an increase in latency interval in DCDA twins with PV-ROM following selective feticide, compared to that with expectant management. Furthermore, selective feticide in cases with PV-ROM of upper sac has a favorable outcome.


Asunto(s)
Aborto Inducido , Rotura Prematura de Membranas Fetales , Femenino , Embarazo , Humanos , Lactante , Resultado del Embarazo , Estudios Retrospectivos , Reducción de Embarazo Multifetal , Gemelos Dicigóticos , Embarazo Gemelar
18.
BMC Anesthesiol ; 24(1): 191, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807059

RESUMEN

BACKGROUND: Balanced propofol sedation is extensively used in endoscopic retrograde cholangiopancreatography (ERCP), but sedation-related adverse events (SRAEs) are common. In various clinical settings, the combination of dexmedetomidine with opioids and benzodiazepines has provided effective sedation with increased safety. The aim of this investigation was to compare the efficacy and safety of dexmedetomidine and propofol for sedation during ERCP. METHODS: Forty-one patients were randomly divided into two groups: the dexmedetomidine (DEX) group and the propofol (PRO) group. Patients in the DEX group received an additional bolus of 0.6 µg kg-1 dexmedetomidine followed by a dexmedetomidine infusion at 1.2 µg kg-1 h-1, whereas the PRO group received 1-2 mg kg-1 of propofol bolus followed by a propofol infusion at 2-3 mg kg-1 h-1. During ERCP, the primary outcome was the incidence of hypoxemia (SpO2 < 90% for > 10 s). Other intraoperative adverse events were also recorded as secondary outcomes, including respiratory depression (respiratory rate of < 10 bpm min-1), hypotension (MAP < 65 mmHg), and bradycardia (HR < 45 beats min-1). RESULTS: The incidence of hypoxemia was significantly reduced in the DEX group compared to the PRO group (0% versus 28.6%, respectively; P = 0.032). Patients in the PRO group exhibited respiratory depression more frequently than patients in the DEX group (35% versus 81%, respectively; P = 0.003). There were no significant differences in terms of hypotension and bradycardia episodes between groups. During the procedures, the satisfaction scores of endoscopists and patients, as well as the pain and procedure memory scores of patients were comparable between groups. CONCLUSION: In comparison with propofol, dexmedetomidine provided adequate sedation safety with no adverse effects on sedation efficacy during ERCP. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2200061468, 25/06/2022.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Dexmedetomidina , Hipnóticos y Sedantes , Propofol , Humanos , Dexmedetomidina/administración & dosificación , Dexmedetomidina/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Propofol/administración & dosificación , Propofol/efectos adversos , Masculino , Femenino , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Anciano , Adulto , Hipoxia/prevención & control , Sedación Consciente/métodos
19.
J Integr Neurosci ; 23(6): 113, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38940095

RESUMEN

Excessively high or synchronized neuronal activity in the brain is the underlying cause of epilepsy, a condition of the central nervous system. Epilepsy is caused mostly by an imbalance in the activity of inhibitory and excitatory neural networks. Recurrent or prolonged seizures lead to neuronal death, which in turn promotes epileptogenesis and epileptic seizures. Ferrous ion-mediated cell death is known as ferroptosis, which is due to the accumulation of lipid peroxidation products resulting from compromise of the glutathione (GSH)-dependent antioxidant system. The pathophysiology of epilepsy has been linked to anomalies in the glutathione peroxidase 4 (GPX4)/GSH redox pathway, lipid peroxidation, and iron metabolism. Studies have shown that inhibiting ferroptosis may alleviate cognitive impairment and decrease seizures, indicating that it is neuroprotective. With the hope of aiding the development of more novel approaches for the management of epilepsy, this research aimed to examine the role of ferroptosis in this disease.


Asunto(s)
Epilepsia , Ferroptosis , Ferroptosis/fisiología , Humanos , Epilepsia/metabolismo , Epilepsia/fisiopatología , Animales , Peroxidación de Lípido/fisiología , Hierro/metabolismo
20.
Pestic Biochem Physiol ; 201: 105904, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685226

RESUMEN

Arsenic (As) and polystyrene nanoplastics (PSNPs) co-exposure induced biotoxicity and ecological risks have attracted wide attention. However, the combined effects of As and PSNPs on the kidney and their underlying mechanisms of toxicities remain to be explored. Here, we investigated the effects of As and PSNPs co-exposure on structure and function in mice kidney, and further explored the possible mechanisms. In this study, we identified that co-exposure to As and PSNPs exhibited conspicuous renal structural damage and pathological changes, accompanied by renal tissue fibrosis (increased protein expression of Collagen I and α-SMA and deposition of collagen fibers), whereas alone exposure to As or PSNPs does not exhibit nephrotoxicity. Subsequently, our results further showed that combined action of As and PSNPs induced mitochondrial oxidative damage and impaired mitochondrial dynamic balance. Furthermore, co-treatment with As and PSNPs activated NCOA4-mediated ferritinophagy and ferroptosis in mice kidney and TCMK-1 cells, which was confirmed by the changes in the expression of ferritinophagy and ferroptosis related indicators (NCOA4, LC3, ATG5, ATG7, FTH1, FTL, GPX4, SLC7A11, FSP1, ACSL4 and PTGS2). Meaningfully, pretreatment with the mtROS-targeted scavenger Mito-TEMPO significantly attenuated As and PSNPs co-exposure induced mitochondrial damage, ferritinophagy and ferroptosis. In conclusion, these findings demonstrated that mtROS-dependent ferritinophagy and ferroptosis are important factors in As and PSNPs co-exposure induced kidney injury and fibrosis. This study provides a new insight into the study of combined toxicity of nanoplastics and heavy metal pollutants.


Asunto(s)
Arsénico , Ferroptosis , Riñón , Mitocondrias , Poliestirenos , Animales , Ferroptosis/efectos de los fármacos , Poliestirenos/toxicidad , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Arsénico/toxicidad , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Masculino , Homeostasis/efectos de los fármacos , Ferritinas/metabolismo , Nanopartículas/toxicidad , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo
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