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1.
Nucleic Acids Res ; 52(3): 1341-1358, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38113276

RESUMEN

MTU1 controls intramitochondrial protein synthesis by catalyzing the 2-thiouridine modification of mitochondrial transfer RNAs (mt-tRNAs). Missense mutations in the MTU1 gene are associated with life-threatening reversible infantile hepatic failure. However, the molecular pathogenesis is not well understood. Here, we investigated 17 mutations associated with this disease, and our results showed that most disease-related mutations are partial loss-of-function mutations, with three mutations being particularly severe. Mutant MTU1 is rapidly degraded by mitochondrial caseinolytic peptidase (CLPP) through a direct interaction with its chaperone protein CLPX. Notably, knockdown of CLPP significantly increased mutant MTU1 protein expression and mt-tRNA 2-thiolation, suggesting that accelerated proteolysis of mutant MTU1 plays a role in disease pathogenesis. In addition, molecular dynamics simulations demonstrated that disease-associated mutations may lead to abnormal intermolecular interactions, thereby impairing MTU1 enzyme activity. Finally, clinical data analysis underscores a significant correlation between patient prognosis and residual 2-thiolation levels, which is partially consistent with the AlphaMissense predictions. These findings provide a comprehensive understanding of MTU1-related diseases, offering prospects for modification-based diagnostics and novel therapeutic strategies centered on targeting CLPP.


Asunto(s)
Mitocondrias , Proteínas Mitocondriales , Péptido Hidrolasas , ARNt Metiltransferasas , Humanos , Endopeptidasa Clp/genética , Endopeptidasa Clp/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Mutación , Péptido Hidrolasas/genética , Proteolisis , ARN Mitocondrial/metabolismo , ARN de Transferencia/metabolismo , ARNt Metiltransferasas/genética , Proteínas Mitocondriales/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(18): e2300291120, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37098060

RESUMEN

Transcranial low-intensity ultrasound is a promising neuromodulation modality, with the advantages of noninvasiveness, deep penetration, and high spatiotemporal accuracy. However, the underlying biological mechanism of ultrasonic neuromodulation remains unclear, hindering the development of efficacious treatments. Here, the well-known Piezo1 was studied through a conditional knockout mouse model as a major mediator for ultrasound neuromodulation ex vivo and in vivo. We showed that Piezo1 knockout (P1KO) in the right motor cortex of mice significantly reduced ultrasound-induced neuronal calcium responses, limb movement, and muscle electromyogram (EMG) responses. We also detected higher Piezo1 expression in the central amygdala (CEA), which was found to be more sensitive to ultrasound stimulation than the cortex was. Knocking out the Piezo1 in CEA neurons showed a significant reduction of response under ultrasound stimulation, while knocking out astrocytic Piezo1 showed no-obvious changes in neuronal responses. Additionally, we excluded an auditory confound by monitoring auditory cortical activation and using smooth waveform ultrasound with randomized parameters to stimulate P1KO ipsilateral and contralateral regions of the same brain and recording evoked movement in the corresponding limb. Thus, we demonstrate that Piezo1 is functionally expressed in different brain regions and that it is an important mediator of ultrasound neuromodulation in the brain, laying the ground for further mechanistic studies of ultrasound.


Asunto(s)
Corteza Auditiva , Encéfalo , Ratones , Animales , Encéfalo/fisiología , Corteza Auditiva/metabolismo , Ultrasonografía , Neuronas/metabolismo , Ratones Noqueados , Canales Iónicos/genética , Canales Iónicos/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(22): e2220575120, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37216521

RESUMEN

Noninvasive control of neuronal activity in the deep brain can be illuminating for probing brain function and treating dysfunctions. Here, we present a sonogenetic approach for controlling distinct mouse behavior with circuit specificity and subsecond temporal resolution. Targeted neurons in subcortical regions were made to express a mutant large conductance mechanosensitive ion channel (MscL-G22S), enabling ultrasound to trigger activity in MscL-expressing neurons in the dorsal striatum and increase locomotion in freely moving mice. Ultrasound stimulation of MscL-expressing neurons in the ventral tegmental area could activate the mesolimbic pathway to trigger dopamine release in the nucleus accumbens and modulate appetitive conditioning. Moreover, sonogenetic stimulation of the subthalamic nuclei of Parkinson's disease model mice improved their motor coordination and mobile time. Neuronal responses to ultrasound pulse trains were rapid, reversible, and repeatable. We also confirmed that the MscL-G22S mutant is more effective to sensitize neurons to ultrasound compared to the wild-type MscL. Altogether, we lay out a sonogenetic approach which can selectively manipulate targeted cells to activate defined neural pathways, affect specific behaviors, and relieve symptoms of neurodegenerative disease.


Asunto(s)
Enfermedades Neurodegenerativas , Núcleo Subtalámico , Ratones , Animales , Encéfalo , Núcleo Subtalámico/fisiología , Núcleo Accumbens , Dopamina/fisiología , Vías Nerviosas
4.
J Virol ; 98(4): e0017124, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38488361

RESUMEN

The global impact of emerging viral infections emphasizes the urgent need for effective broad-spectrum antivirals. The cellular organelle, lipid droplet (LD), is utilized by many types of viruses for replication, but its reduction does not affect cell survival. Therefore, LD is a potential target for developing broad-spectrum antivirals. In this study, we found that 2-bromopalmitate (2 BP), a previously defined palmitoylation inhibitor, depletes LD across all studied cell lines and exerts remarkable antiviral effects on different coronaviruses. We comprehensively utilized 2 BP, alongside other palmitoylation inhibitors such as cerulenin and 2-fluoro palmitic acid (2-FPA), as well as the enhancer palmostatin B and evaluated their impact on LD and the replication of human coronaviruses (hCoV-229E, hCoV-Oc43) and murine hepatitis virus (MHV-A59) at non-cytotoxic concentrations. While cerulenin and 2-FPA exhibited moderate inhibition of viral replication, 2 BP exhibited a much stronger suppressive effect on MHV-A59 replication, although they share similar inhibitory effects on palmitoylation. As expected, palmostatin B significantly enhanced viral replication, it failed to rescue the inhibitory effects of 2 BP, whereas it effectively counteracted the effects of cerulenin and 2-FPA. This suggests that the mechanism that 2 BP used to inhibit viral replication is beyond palmitoylation inhibition. Further investigations unveil that 2 BP uniquely depletes LDs, a phenomenon not exhibited by 2-FPA and cerulenin. Importantly, the depletion of LDs was closely associated with the inhibition of viral replication because the addition of oleic acid to 2 BP significantly rescued LD depletion and its inhibitory effects on MHV-A59. Our findings indicate that the inhibitory effects of 2 BP on viral replication primarily stem from LD disruption rather than palmitoylation inhibition. Intriguingly, fatty acid (FA) assays demonstrated that 2 BP reduces the FA level in mitochondria while concurrently increasing FA levels in the cytoplasm. These results highlight the crucial role of LDs in viral replication and uncover a novel biological activity of 2 BP. These insights contribute to the development of broad-spectrum antiviral strategies. IMPORTANCE: In our study, we conducted a comparative investigation into the antiviral effects of palmitoylation inhibitors including 2-bromopalmitate (2-BP), 2-fluoro palmitic acid (2-FPA), and cerulenin. Surprisingly, we discovered that 2-BP has superior inhibitory effects on viral replication compared to 2-FPA and cerulenin. However, their inhibitory effects on palmitoylation were the same. Intrigued by this finding, we delved deeper into the underlying mechanism of 2-BP's potent antiviral activity, and we unveiled a novel biological activity of 2-BP: depletion of lipid droplets (LDs). Importantly, we also highlighted the crucial role of LDs in viral replication. Our insights shed new light on the antiviral mechanism of LD depletion paving the way for the development of broad-spectrum antiviral strategies by targeting LDs.


Asunto(s)
Antivirales , Coronavirus , Virus de la Hepatitis Murina , Palmitatos , Animales , Humanos , Ratones , Antivirales/farmacología , Antivirales/metabolismo , Cerulenina/metabolismo , Cerulenina/farmacología , Coronavirus/efectos de los fármacos , Coronavirus/fisiología , Gotas Lipídicas/efectos de los fármacos , Palmitatos/farmacología , Ácido Palmítico/farmacología , Ácido Palmítico/metabolismo , Propiolactona/análogos & derivados , Replicación Viral/efectos de los fármacos , Virus de la Hepatitis Murina/efectos de los fármacos , Virus de la Hepatitis Murina/fisiología
5.
PLoS Comput Biol ; 20(9): e1012415, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39226309

RESUMEN

Revealing the relationship between neural network structure and function is one central theme of neuroscience. In the context of working memory (WM), anatomical data suggested that the topological structure of microcircuits within WM gradient network may differ, and the impact of such structural heterogeneity on WM activity remains unknown. Here, we proposed a spiking neural network model that can replicate the fundamental characteristics of WM: delay-period neural activity involves association cortex but not sensory cortex. First, experimentally observed receptor expression gradient along the WM gradient network is reproduced by our network model. Second, by analyzing the correlation between different local structures and duration of WM activity, we demonstrated that small-worldness, excitation-inhibition balance, and cycle structures play crucial roles in sustaining WM-related activity. To elucidate the relationship between the structure and functionality of neural networks, structural circuit gradients in brain should also be subject to further measurement. Finally, combining anatomical data, we simulated the duration of WM activity across different brain regions, its maintenance relies on the interaction between local and distributed networks. Overall, network structural gradient and interaction between local and distributed networks are of great significance for WM.


Asunto(s)
Memoria a Corto Plazo , Modelos Neurológicos , Red Nerviosa , Memoria a Corto Plazo/fisiología , Red Nerviosa/fisiología , Humanos , Biología Computacional , Animales , Encéfalo/fisiología , Simulación por Computador , Neuronas/fisiología , Potenciales de Acción/fisiología
6.
EMBO Rep ; 24(1): e55542, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36394374

RESUMEN

The Zn content in cereal seeds is an important trait for crop production as well as for human health. However, little is known about how Zn is loaded to plant seeds. Here, through a genome-wide association study (GWAS), we identify the Zn-NA (nicotianamine) transporter gene ZmYSL2 that is responsible for loading Zn to maize kernels. High promoter sequence variation in ZmYSL2 most likely drives the natural variation in Zn concentrations in maize kernels. ZmYSL2 is specifically localized on the plasma membrane facing the maternal tissue of the basal endosperm transfer cell layer (BETL) and functions in loading Zn-NA into the BETL. Overexpression of ZmYSL2 increases the Zn concentration in the kernels by 31.6%, which achieves the goal of Zn biofortification of maize. These findings resolve the mystery underlying the loading of Zn into plant seeds, providing an efficient strategy for breeding or engineering maize varieties with enriched Zn nutrition.


Asunto(s)
Estudio de Asociación del Genoma Completo , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Zinc/metabolismo , Fitomejoramiento , Semillas/genética , Proteínas de Transporte de Membrana/genética
7.
J Immunol ; 211(9): 1287-1297, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37702994

RESUMEN

Staphylococcus aureus enterotoxin B (SEB), one of the most common bacterial toxins in food contamination, has been poorly understood in relationship to food allergy outcomes. To investigate whether the ingestion of enterotoxins in food allergens could affect the development of food allergy, OVA-sensitized female BALB/c mice were challenged with OVA added with different doses of SEB or LPS. Allergic symptoms, such as diarrhea rate and hypothermia, could be aggravated in mice challenged with OVA and a low dose of SEB. The increased differentiation of Th2 and reduced expression of CD103 in dendritic cells was found in mice coexposed to SEB and OVA. Additionally, there was an increasing differentiation of Th1 induced by a high dose of SEB. The expression of ST2+ in intestinal mast cells was also increased in mice sensitized with a low dose of SEB and OVA. Employing several in vitro cell culture models showed that the secretion of IL-33 from intestinal epithelial cells and IL-4 from group 2 innate lymphoid cells, activation of bone marrow-derived dendritic cells, and differentiation of naive T cells were induced by SEB and OVA. Our work proved that challenge with low-dose SEB and OVA partly aggravated the food allergy, suggesting a (to our knowledge) new finding of the potential cofactor of food allergy and that the contamination of SEB in food allergens deserves attention for allergic and normal individuals.

8.
Proc Natl Acad Sci U S A ; 119(12): e2118573119, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35290119

RESUMEN

Although catenanes comprising two ring-shaped components can be made in large quantities by templation, the preparation of three-dimensional (3D) catenanes with cage-shaped components is still in its infancy. Here, we report the design and syntheses of two 3D catenanes by a sequence of SN2 reactions in one pot. The resulting triply mechanically interlocked molecules were fully characterized in both the solution and solid states. Mechanistic studies have revealed that a suit[3]ane, which contains a threefold symmetric cage component as the suit and a tribromide component as the body, is formed at elevated temperatures. This suit[3]ane was identified as the key reactive intermediate for the selective formation of the two 3D catenanes which do not represent thermodynamic minima. We foresee a future in which this particular synthetic strategy guides the rational design and production of mechanically interlocked molecules under kinetic control.


Asunto(s)
Catenanos , Rotaxanos , Catenanos/química , Cinética , Rotaxanos/química
9.
J Am Chem Soc ; 146(27): 18616-18625, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38924516

RESUMEN

We report a general and functional-group-tolerant method for the Cu-catalyzed amination of base-sensitive aryl bromides including substrates possessing acidic functional groups and small five-membered heteroarenes. The results presented herein substantially expand the scope of Cu-catalyzed C-N coupling reactions. The combination of L8, an anionic N1,N2-diarylbenzene-1,2-diamine ligand, along with the mild base NaOTMS leads to the formation of a stable yet reactive catalyst that resists deactivation from coordination to heterocycles or charged intermediates. This system enables the use of low catalyst and ligand loadings. Exploiting the differences in nucleophile deprotonation in C-O and C-N coupling reactions catalyzed by Cu·L8 we developed a method to chemoselectively N- and O-arylate a variety of amino alcohol substrates. Employing NaOt-Bu as the base resulted exclusively in C-O coupling when the amino alcohols featured primary alcohols and more hindered amines or aniline groups. Utilizing NaOTMS enabled the ability to override the steric-based selectivity of these reactions completely and exclusively promoted C-N coupling regardless of the structure of the amino alcohol. The ability to invert the observed chemoselectivity is distinct from previously described methods that require protecting group manipulations or rely entirely on steric effects to control reactivity. These results substantially improve the scope of Cu-catalyzed C-N coupling reactions using N1,N2-diarylbenzene-1,2-diamine ligands and introduce a new chemoselective method to arylate amino alcohols.


Asunto(s)
Amino Alcoholes , Cobre , Cobre/química , Catálisis , Aminación , Amino Alcoholes/química , Estructura Molecular , Bromuros/química , Hidrocarburos Bromados/química , Ligandos
10.
J Am Chem Soc ; 146(14): 9801-9810, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38551407

RESUMEN

The sequence-controlled assembly of nucleic acids and amino acids into well-defined superstructures constitutes one of the most revolutionary technologies in modern science. The elaboration of such superstructures from carbohydrates, however, remains elusive and largely unexplored on account of their intrinsic constitutional and configurational complexity, not to mention their inherent conformational flexibility. Here, we report the bottom-up assembly of two classes of hierarchical superstructures that are formed from a highly flexible cyclo-oligosaccharide─namely, cyclofructan-6 (CF-6). The formation of coordinative bonds between the oxygen atoms of CF-6 and alkali metal cations (i) locks a myriad of flexible conformations of CF-6 into a few rigid conformations, (ii) bridges adjacent CF-6 ligands, and (iii) gives rise to the multiple-level assembly of three extended frameworks. The hierarchical superstructures present in these frameworks have been shown to modulate their nanomechanical properties. This research highlights the unique opportunities of constructing convoluted superstructures from carbohydrates and should encourage future endeavors in this underinvestigated field of science.


Asunto(s)
Carbohidratos , Metales , Metales/química , Carbohidratos/química , Conformación Molecular , Aminoácidos
11.
Mol Cancer ; 23(1): 215, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39350121

RESUMEN

The Nab-paclitaxel combined with gemcitabine (AG) regimen is the main chemotherapy regimen for pancreatic cancer, but drug resistance often occurs. Currently, the ability to promote sensitization in drug-resistant cases is an important clinical issue, and the strategy of repurposing conventional drugs is a promising strategy. This study aimed to identify a classic drug that targets chemotherapy resistance's core signaling pathways and combine it with the AG regimen to enhance chemosensitivity. We also aimed to find reliable predictive biomarkers of drug combination sensitivity. Using RNA sequencing, we found that abnormal PI3K/Akt pathway activation plays a central role in mediating resistance to the AG regimen. Subsequently, through internal and external verification of randomly selected AG-resistant patient-derived organoid (PDO) and PDO xenograft models, we discovered for the first time that the classic anti-inflammatory drug sulindac K-80003, an inhibitor of the PI3K/Akt pathway that we focused on, promoted sensitization in half (14/28) of AG-resistant pancreatic ductal adenocarcinoma cases. Through RNA-sequencing, multiplex immunofluorescent staining, and immunohistochemistry experiments, we identified cFAM124A as a novel biomarker through which sulindac K-80003 promotes AG sensitization. Its role as a sensitization marker is explained via the following mechanism: cFAM124A enhances both the mRNA expression of cathepsin L and the activity of the cathepsin L enzyme. This dual effect stimulates the cleavage of RXRα, leading to large amounts of truncated RXRα, which serves as a direct target of K-80003. Consequently, this process results in the pathological activation of the PI3K/Akt pathway. In summary, our study provides a new treatment strategy and novel biological target for patients with drug-resistant pancreatic cancer.


Asunto(s)
Albúminas , Protocolos de Quimioterapia Combinada Antineoplásica , Desoxicitidina , Resistencia a Antineoplásicos , Gemcitabina , Paclitaxel , Neoplasias Pancreáticas , Sulindac , Ensayos Antitumor por Modelo de Xenoinjerto , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Humanos , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Animales , Ratones , Albúminas/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Sulindac/farmacología , Sulindac/análogos & derivados , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Femenino , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/metabolismo , Masculino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos
12.
Int J Cancer ; 154(4): 670-678, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37850323

RESUMEN

Genome-wide association studies (GWAS) have identified two dozen genetic variants that are associated with the risk of pancreatic ductal adenocarcinoma (PDAC), a deadly malignancy. However, a majority of these variants are located in noncoding regions of the genome, which limits the translation of GWAS findings into clinical applications. The regulome-wide association study (RWAS) is a recently developed method for identifying TF binding-induced accessibility regions for diseases. However, their potential connection to PDAC has yet to be fully explored. We evaluated the associations between genetically predicted levels of chromatin accessibility and risk of PDAC by using pan-cancer chromatin accessibility genetic prediction models. Our analysis included 8275 cases and 6723 controls from the PanScan (I, II, and III) and PanC4 consortia. To further refine our results, we also integrated genes associated to allele-specific accessibility quantitative trait loci (as-aQTL) and TF motifs located in the as-aQTL. We found that 50 chromatin accessibility features were associated with PDAC risk at a false discovery rate (FDR) of less than 0.05. A total of 28 RWAS peaks were identified as conditionally significant. By integrating the results from as-aQTL, motif analysis, and RWAS, we identified candidate causal regulatory elements for two potential chromatin accessibility regions (THCA_89956 and ESCA_89167) that are associated with PDAC risk. Our study identified chromatin accessibility features in noncoding genomic regions that are associated with PDAC risk. We also predicted the associated genes and disrupt motifs. Our findings provide new insights into the regulatory mechanisms of noncoding regions for pancreatic tumorigenesis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Páncreas , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Cromatina/genética , Polimorfismo de Nucleótido Simple
13.
Am J Hum Genet ; 108(2): 337-345, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33434492

RESUMEN

Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the Müllerian ducts (MD)/Wölffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.


Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/genética , Anomalías Congénitas/genética , Conductos Paramesonéfricos/anomalías , Conductos Paramesonéfricos/crecimiento & desarrollo , Mutación , Conductos Mesonéfricos/crecimiento & desarrollo , Adulto , Proteína Morfogenética Ósea 4/genética , Proteína Morfogenética Ósea 7/genética , Codón sin Sentido , Femenino , Estudios de Asociación Genética , Pleiotropía Genética , Proteínas Homeobox A10/genética , Proteínas de Homeodominio/genética , Humanos , Factor de Transcripción PAX8/genética , Herencia Paterna , Penetrancia , Proteínas de Dominio T Box/genética , Factores de Transcripción/genética , Proteínas Wnt/genética , Conductos Mesonéfricos/anomalías
14.
Anal Chem ; 96(41): 16338-16345, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39359231

RESUMEN

In situ visualization of microRNA (miRNA) in cancer cells and diseased tissues is essential for advancing our comprehension of the onset and progression of associated diseases. Two-photon (TP) imaging, as an imaging technology with high spatiotemporal resolution, deep tissue penetration, and accurate target quantification, has distinctive advantages over single-photon imaging and has attracted increasing attention. Extensive research has been conducted on two-photon dye-doped silica nanoparticles, which exhibit a large two-photon absorption (TPA) cross-section, high fluorescence quantum yield, and excellent biocompatibility. However, the low abundance of RNA in tumor cells leads to insufficient signal output. Based on functional nucleic acid, a catalyzed hairpin self-assembly (CHA) signal amplification strategy, which has simplicity, robustness, and nonenzymatic characteristics, can achieve the amplification of DNA or RNA signals. Here, a two-photon silica nanoamplifier (TP-SNA) utilizing TP dye-doped silica nanoparticles (SiNPs) and functional nucleic acid was constructed, employing triggering catalyzed hairpin self-assembly and fluorescence resonance energy transfer (FRET) for highly sensitive detection and precise TP imaging of endogenous miRNAs in tumor cells and tissues at varying depths. The TP-SNA demonstrated the capability to detect miR-203 with a detection limit of 33 pM. The maximum two-photon tissue penetration depth of the two-photon nanoamplifier was 210 µm. The two-photon nanoamplifier developed in this study makes full use of the advantages of accurate TP ratiometric bioimaging and the CHA signal amplification strategy, which shows good application value for future transformation into clinical diagnosis.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , MicroARNs , Nanopartículas , Fotones , Dióxido de Silicio , Dióxido de Silicio/química , MicroARNs/análisis , Humanos , Nanopartículas/química , Colorantes Fluorescentes/química , Animales , Ratones , Células HeLa
15.
Anal Chem ; 96(17): 6674-6682, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38642044

RESUMEN

Photodynamic therapy (PDT) is a significant noninvasive therapeutic modality, but it is often limited in its application due to the restricted tissue penetration depth caused by the wavelength limitations of the light source. Two-photon (TP) fluorescence techniques are capable of having an excitation wavelength in the NIR region by absorbing two NIR photons simultaneously, which offers the potential to achieve higher spatial resolution for deep tissue imaging. Thus, the adoption of TP fluorescence techniques affords several discernible benefits for photodynamic therapy. Organic TP dyes possess a high fluorescence quantum yield. However, the biocompatibility of organic TP dyes is poor, and the method of coating organic TP dyes with silica can effectively overcome the limitations. Herein, based on the TP silica nanoparticles, a functionalized intelligent biogenic missile TP-SiNPs-G4(TMPyP4)-dsDNA(DOX)-Aptamer (TGTDDA) was developed for effective TP bioimaging and synergistic targeted photodynamic therapy and chemotherapy in tumors. First, the Sgc8 aptamer was used to target the PTK7 receptor on the surface of tumor cells. Under two-photon light irradiation, the intelligent biogenic missile can be activated for TP fluorescence imaging to identify tumor cells and the photosensitizer assembled on the nanoparticle surface can be activated for photodynamic therapy. Additionally, this intelligent biogenic missile enables the controlled release of doxorubicin (DOX). The innovative strategy substantially enhances the targeted therapeutic effectiveness of cancer cells. The intelligent biogenic missile provides an effective method for the early detection and treatment of tumors, which has a good application prospect in the real-time high-sensitivity diagnosis and treatment of tumors.


Asunto(s)
Imagen Óptica , Fotoquimioterapia , Fotones , Fármacos Fotosensibilizantes , Humanos , Animales , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Ratones , Nanopartículas/química , Doxorrubicina/química , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Dióxido de Silicio/química , Aptámeros de Nucleótidos/química , Colorantes Fluorescentes/química , Neoplasias/tratamiento farmacológico , Neoplasias/diagnóstico por imagen , Antineoplásicos/química , Antineoplásicos/farmacología , Ratones Desnudos , Línea Celular Tumoral , Ratones Endogámicos BALB C
16.
Biochem Biophys Res Commun ; 715: 149999, 2024 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-38678787

RESUMEN

Non-alcoholic fatty liver disease (NAFLD), a chronic liver condition and metabolic disorder, has emerged as a significant health issue worldwide. D-mannose, a natural monosaccharide widely existing in plants and animals, has demonstrated metabolic regulatory properties. However, the effect and mechanism by which D-mannose may counteract NAFLD have not been studied. In this study, network pharmacology followed by molecular docking analysis was utilized to identify potential targets of mannose against NAFLD, and the leptin receptor-deficient, genetically obese db/db mice was employed as an animal model of NAFLD to validate the regulation of D-mannose on core targets. As a result, 67 targets of mannose are predicted associated with NAFLD, which are surprisingly centered on the mechanistic target of rapamycin (mTOR). Further analyses suggest that mTOR signaling is functionally enriched in potential targets of mannose treating NAFLD, and that mannose putatively binds to mTOR as a core mechanism. Expectedly, repeated oral gavage of supraphysiological D-mannose ameliorates liver steatosis of db/db mice, which is based on suppression of hepatic mTOR signaling. Moreover, daily D-mannose administration reduced hepatic expression of lipogenic regulatory genes in counteracting NAFLD. Together, these findings reveal D-mannose as an effective and potential NAFLD therapeutic through mTOR suppression, which holds translational promise.


Asunto(s)
Manosa , Farmacología en Red , Enfermedad del Hígado Graso no Alcohólico , Serina-Treonina Quinasas TOR , Animales , Ratones , Hígado/metabolismo , Hígado/efectos de los fármacos , Manosa/farmacología , Manosa/metabolismo , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
17.
Mol Carcinog ; 63(5): 803-816, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38411267

RESUMEN

Ovarian cancer is a major cause of death among cancer patients. Recent research has shown that the transmembrane emp24 domain (TMED) protein family plays a role in the progression of various types of cancer. In this study, we investigated the expression of TMED3 in ovarian cancer tumors compared to nontumor tissues using immunohistochemical staining. We found that TMED3 was overexpressed in ovarian cancer tumors, and its high expression was associated with poor disease-free and overall survival. To understand the functional implications of TMED3 overexpression in ovarian cancer, we conducted experiments to knockdown TMED3 using short hairpin RNA (shRNA). We observed that TMED3 knockdown resulted in reduced cell viability and migration, as well as increased cell apoptosis. Additionally, in subcutaneous xenograft models in BALB-c nude mice, TMED3 knockdown inhibited tumor growth. Further investigation revealed that SMAD family member 2 (SMAD2) was a downstream target of TMED3, driving ovarian cancer progression. TMED3 stabilized SMAD2 by inhibiting the E3 ligase NEDD4-mediated ubiquitination of SMAD2. To confirm the importance of SMAD2 in TMED3-mediated ovarian cancer, we performed functional rescue experiments and found that SMAD2 played a critical role in this process. Moreover, we discovered that the PI3K-AKT pathway was involved in the promoting effects of TMED3 overexpression on ovarian cancer cells. Overall, our study identifies TMED3 as a prognostic indicator and tumor promoter in ovarian cancer. Its function is likely mediated through the regulation of the SMAD2 and PI3K-AKT signaling pathway. These findings contribute to our understanding of the molecular mechanisms underlying ovarian cancer progression and provide potential targets for therapeutic intervention.


Asunto(s)
Neoplasias Ováricas , Proteínas de Transporte Vesicular , Animales , Femenino , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular , Ratones Desnudos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/metabolismo , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad2/farmacología , Ubiquitinación , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Ubiquitina-Proteína Ligasas Nedd4/metabolismo
18.
J Med Virol ; 96(8): e29838, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39081166

RESUMEN

Enteroviruses are important human pathogens with diverse serotypes, posing a major challenge to develop vaccines for individual serotypes, the success of polio vaccines in controlling and eradicating polio, along with the recent emergence and high prevalence of enterovirus-caused infectious diseases, highlights the importance of enterovirus vaccine development. Given our previous report on enteroviruses weakened by the 2 A S/T125A mutation, we assessed the potential of the EV-A71 2A-125A mutant as a vaccine candidate to address this challenge. We found that the 2A-125A mutant caused transient mild symptoms, low viral loads, and no significant pathological changes mild pathological changes in hSCARB2-KI mice, producing long-lasting cross-neutralizing antibodies against two EV-A71 wild strains. Pre-exposure to the 2A-125A mutant substantially protected against the EV-A71 Isehara wild-type strain, causing minor pathologies, significantly reducing muscle and lung inflammation, and preventing neurological damage, with reduced viral loads in vivo. Pre-exposure also distinctly suppressed the expression of pro-inflammatory cytokines, correlating to the severity of clinical symptoms. Collectively, the EV-A71 2A-125A mutant was attenuated and could generate a robust and protective immune response, suggesting its potential as a vaccine candidate and global solution for specific enterovirus vaccine development.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Enterovirus Humano A , Infecciones por Enterovirus , Vacunas Atenuadas , Carga Viral , Vacunas Virales , Animales , Enterovirus Humano A/inmunología , Enterovirus Humano A/genética , Infecciones por Enterovirus/prevención & control , Infecciones por Enterovirus/inmunología , Infecciones por Enterovirus/virología , Ratones , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Vacunas Virales/inmunología , Vacunas Virales/genética , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/genética , Humanos , Desarrollo de Vacunas , Femenino , Mutación , Citocinas
19.
Ann Surg Oncol ; 31(2): 860-871, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37947979

RESUMEN

BACKGROUND: Neoadjuvant chemoradiotherapy (NCRT) is recommended as the treatment standard for locally advanced esophageal squamous cell carcinoma (ESCC). The use of immunotherapy in the neoadjuvant setting has gained attention. Multiple, clinical trials have explored the efficacy and safety of neoadjuvant immunochemotherapy (NICT). We evaluated the differences in clinicopathologic outcomes and the patterns of lymphatic spread among patients receiving neoadjuvant chemotherapy (NCT), NCRT, and NICT before esophagectomy for locally advanced ESCC. METHODS: A total of 702 patients with ESCC who completed transthoracic esophagectomy followed neoadjuvant therapy were included. Pathological characteristics, including pathologic complete response (pCR), tumor regression grade (TRG) score and patterns of lymphatic spread, were evaluated. RESULTS: Compared with the NCT group, the NCRT group and NICT group had an advantage in pathological response (P < 0.05). The pCR rate was 8.1% in the NCT group, 29.9% in the NCRT group, and 23.6% in the NICT group. The TRG score (P < 0.05) and pathologic T stage (P < 0.05) in the NCT group were significantly higher. Compared with NICT, NCRT can significantly reduce the rate of lymph node metastasis rate in station 1R (0 vs. 3.4%, P < 0.05) and 2R (1.1% vs. 6.8%, P < 0.05). Subgroup analysis according to the tumor location distribution showed that NICT group had higher lymph node metastasis rate in station 2R (9.1%) in middle thoracic cases (P < 0.05) and in station 18 (7.5%) (P < 0.05) in lower thoracic cases. CONCLUSIONS: NCRT or NICT followed by surgery may result in a promising pCR rate and show a better performance in therapeutic response of primary lesion. For patients with lymph node metastasis in station 1R and 2R, NCRT should be the optimal preoperative treatment strategy.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/cirugía , Terapia Neoadyuvante , Neoplasias Esofágicas/patología , Metástasis Linfática , Quimioradioterapia , Inmunoterapia , Esofagectomía
20.
Plant Cell Environ ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016637

RESUMEN

Wheat yellow mosaic virus (WYMV) causes severe viral wheat disease in Asia. The WYMV P1 protein encoded by RNA2 has viral suppressor of RNA silencing (VSR) activity to facilitate virus infection, however, VSR activity has not been identified for P2 protein encoded by RNA2. In this study, P2 protein exhibited strong VSR activity in Nicotiana benthamiana at the four-leaf stage, and point mutants P70A and G230A lost VSR activity. Protein P2 interacted with calmodulin (CaM) protein, a gene-silencing associated protein, while point mutants P70A and G230A did not interact with it. Competitive bimolecular fluorescence complementation and competitive co-immunoprecipitation experiments showed that P2 interfered with the interaction between CaM and calmodulin-binding transcription activator 3 (CAMTA3), but the point mutants P70A and G230A could not. Mechanical inoculation of wheat with in vitro transcripts of WYMV infectious cDNA clone further confirmed that VSR-deficient mutants P70A and G230A decreased WYMV infection in wheat plants compared with the wild type. In addition, RNA silencing, temperature, ubiquitination and autophagy had significant effects on accumulation of P2 protein in N. benthamiana leaves. In conclusion, WYMV P2 plays a VSR role in N. benthamiana and promotes virus infection by interfering with calmodulin-related antiviral RNAi defense.

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