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1.
Neural Regen Res ; 20(6): 1665-1680, 2025 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-39104097

RESUMEN

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

2.
Neuron ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39305894

RESUMEN

A remaining challenge for genetically encoded voltage indicators (GEVIs) is the reliable detection of excitatory postsynaptic potentials (EPSPs). Here, we developed ASAP5 as a GEVI with enhanced activation kinetics and responsivity near resting membrane potentials for improved detection of both spiking and subthreshold activity. ASAP5 reported action potentials (APs) in vivo with higher signal-to-noise ratios than previous GEVIs and successfully detected graded and subthreshold responses to sensory stimuli in single two-photon trials. In cultured rat or human neurons, somatic ASAP5 reported synaptic events propagating centripetally and could detect ∼1-mV EPSPs. By imaging spontaneous EPSPs throughout dendrites, we found that EPSP amplitudes decay exponentially during propagation and that amplitude at the initiation site generally increases with distance from the soma. These results extend the applications of voltage imaging to the quantal response domain, including in human neurons, opening up the possibility of high-throughput, high-content characterization of neuronal dysfunction in disease.

3.
Cell Mol Immunol ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300319

RESUMEN

Hepatocellular carcinoma (HCC) is a highly malignant tumor with significant global health implications. The role of CD4+ T cells, particularly conventional CD4+ T cells (Tconvs), in HCC progression remains unexplored. Furthermore, epigenetic factors are crucial in immune regulation, yet their specific role in HCC-infiltrating Tconv cells remains elusive. This study elucidates the role of MATR3, an epigenetic regulator, in modulating Tconv activity and immune evasion within the HCC microenvironment. Reanalysis of the scRNA-seq data revealed that early activation of CD4+ T cells is crucial for establishing an antitumor immune response. In vivo and in vitro experiments revealed that Tconv enhances cDC1-induced CD8+ T-cell activation. Screening identified MATR3 as a critical regulator of Tconv function, which is necessary for antitumour activity but harmful when overexpressed. Excessive MATR3 expression exacerbates Tconv exhaustion and impairs function by recruiting the SWI/SNF complex to relax chromatin in the TOX promoter region, leading to aberrant transcriptional changes. In summary, MATR3 is an HCC-specific epigenetic checkpoint that bidirectionally regulates Tconv antitumour immunity, suggesting new therapeutic strategies targeting epigenetic regulators to enhance antitumour immunity in HCC.

4.
Nat Prod Res ; : 1-7, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39301610

RESUMEN

Phytochemical investigation of the n-butanol extracts of the herbaceous stems of Epheda intermedia led to the isolation of eight flavonoids that included three new flavonoid glycosides (1-3) and five previously reported analogues (4-8). Their structures have been identified on the basis of various spectral data. Besides, all the flavonoids were tested in vitro for their ability to inhibit α-glucosidase under the positive control of acarbose, and the results indicated that none of them exhibited significant inhibitory effect on α-glucosidase at 100 µM.

5.
Small Methods ; : e2401221, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291906

RESUMEN

Regulating the distribution of surface elements in lithium-rich cathode materials can effectively change the electrochemical performance of cathode materials. Considering that the enrichment of Mn element on the surface is the main reason for the irreversible phase transition and dissolution of its surface structure, which in turn is the main reason for performance degradation. Based on the molten salt-assisted sintering method, a lithium rich cathode material with surface rich Ni and Co is designed and prepared. The surface enrichment of Ni and Co effectively reduces the dissolution of Mn, promotes the occurrence of irreversible collapse of surface structure from layered phase to rock salt phase on the material surface, improves the stability of surface crystal phase structure, and improves the cycling stability of positive electrode materials. Notably, after 500 cycles at 1 C current density, the discharge-specific capacity attained 189.8 mAh g -1, with a capacity retention rate of 88.9%, indicating a 42.1% improvement in capacity retention. Molten salt treatment is widely used in the modification of positive electrode materials. The research work will provide new ideas for improving the stability of lithium rich materials and promoting their commercial applications.

6.
MedComm (2020) ; 5(9): e678, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39188937

RESUMEN

Tumor recurrence is a life-threatening complication after liver transplantation (LT) for hepatocellular carcinoma (HCC). Precise recurrence risk stratification before transplantation is essential for the management of recipients. Here, we aimed to establish an inflammation-related prediction model for posttransplant HCC recurrence based on pretransplant peripheral cytokine profiling. Two hundred and ninety-three patients who underwent LT in two independent medical centers were enrolled, and their pretransplant plasma samples were sent for cytokine profiling. We identified four independent risk factors, including alpha-fetoprotein, systemic immune-inflammation index, interleukin 6, and osteocalcin in the training cohort (n = 190) by COX regression analysis. A prediction model named inflammatory fingerprint (IFP) was established based on the above factors. The IFP effectively predicted posttransplant recurrence (area under the receiver operating characteristic curve [AUROC]: 0.792, C-index: 0.736). The high IFP group recipients had significantly worse 3-year recurrence-free survival rates (37.9 vs. 86.9%, p < 0.001). Simultaneous T-cell profiling revealed that recipients with high IFP were characterized by impaired T cell function. The IFP also performed well in the validation cohort (n = 103, AUROC: 0.807, C-index: 0.681). In conclusion, the IFP efficiently predicted posttransplant HCC recurrence and helped to refine pretransplant risk stratification. Impaired T cell function might be the intrinsic mechanism for the high recurrence risk of recipients in the high IFP group.

7.
Artículo en Inglés | MEDLINE | ID: mdl-39192518

RESUMEN

BACKGROUND: Sarcopenia is associated with unfavourable long-term survival in patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC). However, the impact of myosteatosis and muscle loss on patient prognosis has not been investigated. METHODS: Seven hundred fifty-six HCC patients who received LT at 3 transplant centres were included. Computed tomography (CT) images of recipients were collected to measure skeletal muscle index (SMI) and skeletal muscle radiodensity (SMRA). The impact of myosteatosis on the prognosis of sarcopenic and non-sarcopenic patients was studied separately. Muscle status was evaluated based on the presence of sarcopenia and myosteatosis. The muscle loss of 342 males was calculated as the relative change of SMI between pre- and post-LT evaluations. Cox regression models were used to identify predictors of overall survival (OS) and recurrence-free survival (RFS). RESULTS: The study comprised 673 males and 83 females. The median follow-up time was 31 months (interquartile range, 19-43 months). Prior to LT, 267 (39.7%) and 187 (27.8%) males were defined as sarcopenic (low-SMI) and myosteatotic (low-SMRA), respectively. For sarcopenic recipients, the presence of myosteatosis was followed by a 23.6% decrease in 5 year OS (P < 0.001) and a 15.0% decrease in 5 year RFS (P = 0.014). Univariate and multivariate analyses revealed that muscle status was an independent predictor of OS [hazard ratio (HR), 1.569; 95% confidence interval (CI), 1.317-1.869; P < 0.001] and RFS (HR, 1.369; 95% CI, 1.182-1.586; P < 0.001). Postoperatively, a muscle loss >14.2% was an independent risk factor for poor OS (HR, 2.286; 95% CI, 1.358-3.849; P = 0.002) and RFS (HR, 2.219; 95% CI, 1.418-3.471; P < 0.001) in non-sarcopenic recipients (N = 209). CONCLUSIONS: Pre-transplant myosteatosis aggravated the adverse impact of sarcopenia on liver transplant outcomes in male HCC patients. Post-transplant muscle loss might assist in prognostic stratification of recipients without pre-existing sarcopenia, intriguing new insights into individualized management.

8.
BMC Cancer ; 24(1): 1042, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39179959

RESUMEN

BACKGROUND: Chitinase-3 like-protein-1 (CHI3L1) is a member of the mammalian chitinase-like proteins and elevated serum CHI3L1 level has been proved to be associated with poor prognosis in hepatocellular carcinoma (HCC). This study aimed to investigate the relationship between serum CHI3L1 levels and body composition parameters in patients with HCC after liver transplantation (LT). METHODS: This retrospective study enrolled 200 patients after LT for HCC. Blood samples were collected and serum concentrations of CHI3L1 were measured by enzyme-linked immunosorbent assay. Computer tomography (CT) were used to estimate skeletal muscle and adipose tissue mass. Spearman's rank correlation test was performed to assess associations between serum CHI3L1 levels and these body composition parameters. A Cox proportional-hazards regression model was performed to identify independent prognostic factors. Overall survival (OS) and recurrence-free survival (RFS) curves were constructed using the Kaplan-Meier method and compared by the log-rank test. RESULTS: Total 71 patients (35.5%) were diagnosed with myosteatosis according to skeletal muscle radiation attenuation (SMRA). The 5-year OS rates were 66.9% in non-myosteatosis group, significantly higher than 49.5% in myosteatosis group (p = 0.025), while the RFS of myosteatosis group (5-year RFS: 52.6%) or non-myosteatosis group (5-year RFS: 42.0%) shown no significant difference (p = 0.068). The serum CHI3L1 level were significantly negative correlated with SMRA (r = -0.3, p < 0.001). Interestingly, in patients with myosteatosis, Kaplan-Meier analysis revealed that elevated serum CHI3L1 levels were associated with worse OS (p < 0.001) and RFS (p = 0.047). However, in patients without myosteatosis, Kaplan-Meier analysis found elevated serum CHI3L1 levels were not associated with OS (p = 0.070) or RFS (p = 0.104). CONCLUSIONS: Elevated CHI3L1 was negatively correlated with SMRA, and predicted poorer prognosis in Chinese population after LT for HCC, especially in those patients with concomitant myosteatosis. Monitoring serum CHI3L1 can predict prognosis and effectively guide individual nutrition intervention.


Asunto(s)
Biomarcadores de Tumor , Carcinoma Hepatocelular , Proteína 1 Similar a Quitinasa-3 , Neoplasias Hepáticas , Humanos , Proteína 1 Similar a Quitinasa-3/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Femenino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Biomarcadores de Tumor/sangre , Composición Corporal , Músculo Esquelético/patología , Músculo Esquelético/metabolismo , Músculo Esquelético/diagnóstico por imagen , Trasplante de Hígado , Adulto , Anciano , Tejido Adiposo/patología , Tejido Adiposo/metabolismo , Estimación de Kaplan-Meier , Tomografía Computarizada por Rayos X
9.
Artículo en Inglés | MEDLINE | ID: mdl-39153567

RESUMEN

OBJECTIVE: This study aims to link aberrant endogenous retroviruses (ERVs) activation and osteoarthritis (OA) progression by comparing the chromatin accessibility and transcriptomic landscapes of diseased or intact joint tissues of OA patients. METHOD: We performed ERVs-centric analysis on published ATAC-seq and RNA-seq data from OA patients' cartilage tissues. Here, we compared the outer region of the lateral tibial plateau, representing intact cartilage, to the inner region of the medial tibial plateau, representing damaged cartilage. In addition, cartilage tissue sections from OA patients and post-traumatic OA mouse models were assayed for global H3K9me3 abundance through immunohistochemistry staining. RESULTS: Chromatin accessibility and transcription of ERVs, particularly from evolutionarily "intermediate age" ERVs families (ERV1 and ERVL), were enriched and elevated in OA cartilage. This integrative analysis suggests that H3K9me3-related heterochromatin loss might be mechanistically connected to ERV activation in OA tissue. We further verified that global H3K9me3 levels were reduced in diseased cartilage relative to intact tissue in OA patients and injury-induced OA mice. CONCLUSION: The findings suggest a compelling hypothesis that the loss of H3K9me3, either due to aging or cellular stressors, may lead to ERVs reactivation that contributes to tissue inflammation and OA progression. This study unveils the intricate relationship between epigenetic alterations, ERVs activation, and OA, paving the way for potential therapeutic interventions targeting these pathogenic mechanisms.

10.
Cancer Immunol Res ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115356

RESUMEN

The efficacy of immune checkpoint inhibitors (ICI) in the treatment of hepatocellular carcinoma (HCC) remains limited, highlighting the need for further investigation into the underlying mechanisms. Accumulating evidence indicates that tumor-associated macrophages (TAMs) within the tumor microenvironment (TME) are implicated in immune evasion and treatment resistance. This study aimed to explore the contribution of TAMs in the HCC TME. Our findings reveal the critical involvement of CX3C motif chemokine receptor 1 (CX3CR1)-positive TAMs in inducing T cell exhaustion through interleukin-27 (IL-27) secretion, providing valuable insights into the mechanisms underlying the suboptimal efficacy of anti-PD-1 therapy in HCC. Moreover, we identified prostaglandin E2 (PGE2), released by immune-attacked tumor cells, as a key regulator of CX3CR1+ TAM phenotype transition. To augment the therapeutic response to current anti-PD-1 therapy, we propose an innovative treatment strategy that incorporates targeting CX3CR1+ TAMs in addition to anti-PD-1 therapy. In conclusion, our study contributes to the understanding of TAMs' role in cancer immunotherapy and highlights potential clinical implications for HCC treatment. The combination of targeting CX3CR1+ TAMs with anti-PD-1 therapy holds promise for enhancing the efficacy of immunotherapeutic interventions in HCC patients.

11.
Int J Ophthalmol ; 17(8): 1423-1430, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39156780

RESUMEN

AIM: To explore the prognostic factors for lacrimal gland adenoid cystic carcinoma (LGACC) in Chinese patients. METHODS: Clinical and histopathological data were reviewed in patients with pathologically confirmed LGACC. Local recurrence, metastasis, and disease-specific death were the main outcome measures. Univariate and multivariate analyses were performed by the Kaplan-Meier method and a Cox proportional hazard model. RESULTS: This retrospective cohort study included 45 patients with pathologically confirmed LGACC between January 2008 and June 2022. Tumor (T) classification (P=0.005), nodal metastasis (N) classification (P=0.018) and positive margin (P=0.008) were independent risk factors of recurrence; T (P=0.013) and N (P=0.003) classification and the basaloid tumor type (P=0.032) were independent risk factors for metastasis; T classification (P<0.001) was an independent factor of death of disease. In the further analysis, the durations from first surgery to radiotherapy is correlated with metastatic risk in LGACC patients with basaloid component (P=0.022). CONCLUSION: Histological subtype should be emphasized when evaluating prognosis and guiding treatment. Timely radiotherapy may reduce the risk of metastasis in patients with basaloid component.

12.
Front Neurol ; 15: 1413023, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39206290

RESUMEN

Epilepsy is characterized by abnormal synchronous electrical activity of neurons in the brain. The blood-brain barrier, which is mainly composed of endothelial cells, pericytes, astrocytes and other cell types and is formed by connections between a variety of cells, is the key physiological structure connecting the blood and brain tissue and is critical for maintaining the microenvironment in the brain. Physiologically, the blood-brain barrier controls the microenvironment in the brain mainly by regulating the passage of various substances. Disruption of the blood-brain barrier and increased leakage of specific substances, which ultimately leading to weakened cell junctions and abnormal regulation of ion concentrations, have been observed during the development and progression of epilepsy in both clinical studies and animal models. In addition, disruption of the blood-brain barrier increases drug resistance through interference with drug trafficking mechanisms. The changes in the blood-brain barrier in epilepsy mainly affect molecular pathways associated with angiogenesis, inflammation, and oxidative stress. Further research on biomarkers is a promising direction for the development of new therapeutic strategies.

13.
Int J Biol Macromol ; 277(Pt 2): 133632, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38971279

RESUMEN

In cyanobacteria, Elongation factor Tu (EF-Tu) plays a crucial role in the repair of photosystem II (PSII), which is highly susceptible to oxidative stress induced by light exposure and regulated by reactive oxygen species (ROS). However, the specific molecular mechanism governing the functional regulation of EF-Tu by ROS remains unclear. Previous research has shown that a mutated EF-Tu, where C82 is substituted with a Ser residue, can alleviate photoinhibition, highlighting the important role of C82 in EF-Tu photosensitivity. In this study, we elucidated how ROS deactivate EF-Tu by examining the crystal structures of EF-Tu in both wild-type and mutated form (C82S) individually at resolutions of 1.7 Šand 2.0 Šin Synechococcus elongatus PCC 7942 complexed with GDP. Specifically, the GDP-bound form of EF-Tu adopts an open conformation with C82 located internally, making it resistant to oxidation. Coordinated conformational changes in switches I and II create a tunnel that positions C82 for ROS interaction, revealing the vulnerability of the closed conformation of EF-Tu to oxidation. An analysis of these two structures reveals that the precise spatial arrangement of C82 plays a crucial role in modulating EF-Tu's response to ROS, serving as a regulatory element that governs photosynthetic biosynthesis.


Asunto(s)
Factor Tu de Elongación Peptídica , Especies Reactivas de Oxígeno , Synechococcus , Synechococcus/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor Tu de Elongación Peptídica/metabolismo , Factor Tu de Elongación Peptídica/química , Modelos Moleculares , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Conformación Proteica , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/química
14.
Environ Sci Pollut Res Int ; 31(35): 47899-47910, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39012533

RESUMEN

The distribution coefficient (Kd) of radionuclides is a crucial parameter in assessing the safety of high-level radioactive waste (HLW) geological repository. It is determined in the laboratory through batch and column experiments. However, differences in obtained Kd values from distinct experiments have not been thoroughly assessed and compared. This study evaluated strontium (Sr) sorption on different granite materials using static batch and dynamic experiments (column and core-flooding experiments). The results from batch sorption experiments showed higher Sr sorption on granite under acidic and strongly alkaline conditions, low solid-liquid ratios, and low ionic strength. In column experiments, a two-site sorption model was used to simulate Sr transport in crushed granite and mixed pure minerals. The sorption of Sr on crushed granite exhibited a higher affinity than that of mixed pure minerals. The dual-porosity transport model was employed to investigate Sr transport behavior in fractured granite in the core-flooding experiment. Kd obtained from batch sorption experiments are four to twenty times higher than those from column experiments, and two to three orders of magnitude higher than that from a core-flooding experiment. The results of this study provide valuable insights into safety assessment for the HLW geological repository.


Asunto(s)
Residuos Radiactivos , Dióxido de Silicio , Estroncio , Estroncio/química , Dióxido de Silicio/química , Adsorción
15.
Org Lett ; 26(30): 6335-6340, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39046225

RESUMEN

An unprecedented trimethylsilyl trifluoromethanesulfonate (TMSOTf)-promoted selective double insertion of isocyanides into aldehydes was developed, providing an efficient protocol for synthetically challenging ß-carbonyl α-iminoamides. The given approach is applicable for a diverse selection of readily accessible aldehydes, along with isocyanides serving as essential precursors for "amide" and "imine" scaffolds. The versatile transformations of the given products were demonstrated, and the pivotal intermediates for the plausible mechanism were identified.

17.
Adv Mater ; 36(35): e2402419, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38923058

RESUMEN

Releasing epitaxial perovskite oxide films from their native oxide substrates produces high quality, 2D-material-like monocrystalline freestanding oxide membranes, as potential key components for the next-generation electronic devices. Two major obstacles still limit their practical applications: macroscopic material defects (mainly cracks) that lowers uniformity and yield, and the high cost of the consumed oxide substrates. Here, a two-step film transfer method and a substrate recycling method enable repetitive fabrication of millimeter-scale, fully-connected freestanding oxide films of various chemical compositions from the same substrates; arrays of capacitor and resistor devices based on these oxides transferred on silicon indicate high uniformity, low sample-to-sample variation, and satisfactory electrical connectivity. The two-step transfer suppresses crack formation by avoiding buckling-delamination-type relaxation of epitaxial strain, and the key point to achieve substrate reuse is to remove the residual Al species bonded to the substrate surfaces. The mitigation of such long-lasting issues in freestanding oxide fabrication techniques may eventually pave roads toward future industrial-grade devices, as well as enabling many research opportunities in fundamental physics.

18.
Exploration (Beijing) ; 4(3): 20230086, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38939869

RESUMEN

The ongoing mutations of the SARS-CoV-2 pose serious challenges to the efficacy of the available antiviral drugs, and new drugs with fantastic efficacy are always deserved investigation. Here, a nanobody called IBT-CoV144 is reported, which exhibits broad neutralizing activity against SARS-CoV-2 by inducing the conformation of spike trimer dimers. IBT-CoV144 was isolated from an immunized alpaca using the RBD of wild-type SARS-CoV-2, and it showed strong cross-reactive binding and neutralizing potency against diverse SARS-CoV-2 variants, including Omicron subvariants. Moreover, the prophylactically and therapeutically intranasal administration of IBT-CoV144 confers fantastic protective efficacy against the challenge of Omicron BA.1 variant in BALB/c mice model. The structure analysis of the complex between spike (S) protein, conducted using Cryo-EM, revealed a special conformation known as the trimer dimers. This conformation is formed by two trimers, with six RBDs in the "up" state and bound by six VHHs. IBT-CoV144 binds to the lateral region of the RBD on the S protein, facilitating the aggregation of S proteins. This aggregation results in steric hindrance, which disrupts the recognition of the virus by ACE2 on host cells. The discovery of IBT-CoV144 will provide valuable insights for the development of advanced therapeutics and the design of next-generation vaccines.

19.
bioRxiv ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38915677

RESUMEN

Motor skill learning induces long-lasting synaptic plasticity at not only the inputs, such as dendritic spines1-4, but also at the outputs to the striatum of motor cortical neurons5,6. However, very little is known about the activity and structural plasticity of corticostriatal axons during learning in the adult brain. Here, we used longitudinal in vivo two-photon imaging to monitor the activity and structure of thousands of corticostriatal axonal boutons in the dorsolateral striatum in awake mice. We found that learning a new motor skill induces dynamic regulation of axonal boutons. The activities of motor corticostriatal axonal boutons exhibited selectivity for rewarded movements (RM) and un-rewarded movements (UM). Strikingly, boutons on the same axonal branches showed diverse responses during behavior. Motor learning significantly increased the fraction of RM boutons and reduced the heterogeneity of bouton activities. Moreover, motor learning-induced profound structural dynamism in boutons. By combining structural and functional imaging, we identified that newly formed axonal boutons are more likely to exhibit selectivity for RM and are stabilized during motor learning, while UM boutons are selectively eliminated. Our results highlight a novel form of plasticity at corticostriatal axons induced by motor learning, indicating that motor corticostriatal axonal boutons undergo dynamic reorganization that facilitates the acquisition and execution of motor skills.

20.
J Adv Res ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38944238

RESUMEN

INTRODUCTION: The immunosuppressive capacity of mesenchymal stem cells (MSCs) is dependent on the "license" of several pro-inflammatory factors to express immunosuppressive molecular profiles, which determines the therapeutic efficacy of MSCs in immune-mediated inflammatory diseases. Of those, interferon-γ (IFN-γ) is a key inducer for the expression of immunosuppressive molecular profiles; however, the mechanism underlying this effect is unknown. OBJECTIVES: To elucidate the regulation mechanism and biological functions of N6-methyladenosine (m6A) modification in the immunosuppressive functions by the IFN-γ-licensing MSCs. METHODS: Epitranscriptomic microarray analysis and MeRIP-qPCR assay were performed to identify the regulatory effect of WTAP in the IFN-γ-licensing MSCs. RIP-qPCR, western blot, qRT-PCR and RNA stability assays were used to determine the regulation of WTAP/m6A/YTHDF1 signaling axis in the expression of immunosuppressive molecules. Further, functional capacity of T cells was tested using flow cytometry, and both DSS-induced colitis mice and CIA mice were constructed to clarify the effect of WTAP and YTHDF1 in MSC-mediated immunosuppression. RESULTS: We identified that IFN-γ increased the m6A methylation levels of immunosuppressive molecules, while WTAP deficiency abolished the IFN-γ-induced promotion of m6A modification. IFN-γ activated ERK signaling, which induced WTAP phosphorylation. Additionally, the stabilization of WTAP post-transcriptionally increased the mRNA expression of immunosuppressive molecules (IDO1, PD-L1, ICAM1, and VCAM1) in an m6A-YTHDF1-dependent manner; this effect further impacted the immunosuppressive capacity of IFN-γ licensing MSCs on activated T cells. Notably, WTAP/YTHDF1 overexpression enhanced the therapeutic efficacy of IFN-γ licensing MSCs and restructures the ecology of inflammation in both colitis and arthritis models. CONCLUSION: Our results showed that m6A modification of IDO1, PD-L1, ICAM1, and VCAM1 mRNA mediated by WTAP-YTHDF1 is involved in the regulation of IFN-γ licensing MSCs immunosuppressive abilities, and shed a light to enhance the clinical therapeutic potential of IFN-γ-licensing MSCs.

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