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1.
Cell ; 172(5): 937-951.e18, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29456082

RESUMO

piRNAs (Piwi-interacting small RNAs) engage Piwi Argonautes to silence transposons and promote fertility in animal germlines. Genetic and computational studies have suggested that C. elegans piRNAs tolerate mismatched pairing and in principle could target every transcript. Here we employ in vivo cross-linking to identify transcriptome-wide interactions between piRNAs and target RNAs. We show that piRNAs engage all germline mRNAs and that piRNA binding follows microRNA-like pairing rules. Targeting correlates better with binding energy than with piRNA abundance, suggesting that piRNA concentration does not limit targeting. In mRNAs silenced by piRNAs, secondary small RNAs accumulate at the center and ends of piRNA binding sites. In germline-expressed mRNAs, however, targeting by the CSR-1 Argonaute correlates with reduced piRNA binding density and suppression of piRNA-associated secondary small RNAs. Our findings reveal physiologically important and nuanced regulation of individual piRNA targets and provide evidence for a comprehensive post-transcriptional regulatory step in germline gene expression.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Células Germinativas/metabolismo , RNA Interferente Pequeno/metabolismo , Sequência de Aminoácidos , Animais , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Proteínas de Caenorhabditis elegans/química , Quimera/metabolismo , Inativação Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Nature ; 632(8024): 267-272, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38987606

RESUMO

The fermionic Hubbard model (FHM)1 describes a wide range of physical phenomena resulting from strong electron-electron correlations, including conjectured mechanisms for unconventional superconductivity. Resolving its low-temperature physics is, however, challenging theoretically or numerically. Ultracold fermions in optical lattices2,3 provide a clean and well-controlled platform offering a path to simulate the FHM. Doping the antiferromagnetic ground state of a FHM simulator at half-filling is expected to yield various exotic phases, including stripe order4, pseudogap5, and d-wave superfluid6, offering valuable insights into high-temperature superconductivity7-9. Although the observation of antiferromagnetic correlations over short10 and extended distances11 has been obtained, the antiferromagnetic phase has yet to be realized as it requires sufficiently low temperatures in a large and uniform quantum simulator. Here we report the observation of the antiferromagnetic phase transition in a three-dimensional fermionic Hubbard system comprising lithium-6 atoms in a uniform optical lattice with approximately 800,000 sites. When the interaction strength, temperature and doping concentration are finely tuned to approach their respective critical values, a sharp increase in the spin structure factor is observed. These observations can be well described by a power-law divergence, with a critical exponent of 1.396 from the Heisenberg universality class12. At half-filling and with optimal interaction strength, the measured spin structure factor reaches 123(8), signifying the establishment of an antiferromagnetic phase. Our results provide opportunities for exploring the low-temperature phase diagram of the FHM.

3.
Proc Natl Acad Sci U S A ; 121(28): e2403143121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38959041

RESUMO

Currently, the nanofluidic synapse can only perform basic neuromorphic pulse patterns. One immediate problem that needs to be addressed to further its capability of brain-like computing is the realization of a nanofluidic spiking device. Here, we report the use of a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate membrane to achieve bionic ionic current-induced spiking. In addition to the simulation of various electrical pulse patterns, our synapse could produce transmembrane ionic current-induced spiking, which is highly analogous to biological action potentials with similar phases and excitability. Moreover, the spiking properties could be modulated by ions and neurochemicals. We expect that this work could contribute to biomimetic spiking computing in solution.


Assuntos
Potenciais de Ação , Poliestirenos , Sinapses , Potenciais de Ação/fisiologia , Sinapses/fisiologia , Poliestirenos/química , Nanotecnologia/métodos , Nanotecnologia/instrumentação
4.
Hum Mol Genet ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39146503

RESUMO

CD2-Associated protein (CD2AP) is a candidate susceptibility gene for Alzheimer's disease, but its role in the mammalian central nervous system remains largely unknown. We show that CD2AP protein is broadly expressed in the adult mouse brain, including within cortical and hippocampal neurons, where it is detected at pre-synaptic terminals. Deletion of Cd2ap altered dendritic branching and spine density, and impaired ubiquitin-proteasome system activity. Moreover, in mice harboring either one or two copies of a germline Cd2ap null allele, we noted increased paired-pulse facilitation at hippocampal Schaffer-collateral synapses, consistent with a haploinsufficient requirement for pre-synaptic release. Whereas conditional Cd2ap knockout in the brain revealed no gross behavioral deficits in either 3.5- or 12-month-old mice, Cd2ap heterozygous mice demonstrated subtle impairments in discrimination learning using a touchscreen task. Based on unbiased proteomics, partial or complete loss of Cd2ap triggered perturbation of proteins with roles in protein folding, lipid metabolism, proteostasis, and synaptic function. Overall, our results reveal conserved, dose-sensitive requirements for CD2AP in the maintenance of neuronal structure and function, including synaptic homeostasis and plasticity, and inform our understanding of possible cell-type specific mechanisms in Alzheimer's Disease.

5.
Plant Cell ; 35(5): 1474-1495, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36781400

RESUMO

The major antioxidant L-ascorbic acid (AsA) plays important roles in plant growth, development, and stress responses. However, the importance of AsA concentration and the regulation of AsA metabolism in plant reproduction remain unclear. In Arabidopsis (Arabidopsis thaliana) anthers, the tapetum monolayer undergoes cell differentiation to support pollen development. Here, we report that a transcription factor, DEFECTIVE IN TAPETAL DEVELOPMENT AND FUNCTION 1 (TDF1), inhibits tapetal cell division leading to cell differentiation. We identified SKEWED5-SIMILAR 18 (SKS18) as a downstream target of TDF1. Enzymatic assays showed that SKS18, annotated as a multicopper oxidase-like protein, has ascorbate oxidase activity, leading to AsA oxidation. We also show that VITAMIN C DEFECTIVE1 (VTC1), an AsA biosynthetic enzyme, is negatively controlled by TDF1 to maintain proper AsA contents. Consistently, either knockout of SKS18 or VTC1 overexpression raised AsA concentrations, resulting in extra tapetal cells, while SKS18 overexpression in tdf1 or the vtc1-3 tdf1 double mutant mitigated their defective tapetum. We observed that high AsA concentrations caused lower accumulation of reactive oxygen species (ROS) in tapetal cells. Overexpression of ROS scavenging genes in tapetum restored excess cell divisions. Thus, our findings demonstrate that TDF1-regulated AsA balances cell division and cell differentiation in the tapetum through governing ROS homeostasis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Ascórbico , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Divisão Celular , Diferenciação Celular/genética , Homeostase , Regulação da Expressão Gênica de Plantas
6.
Nature ; 579(7797): 118-122, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103178

RESUMO

It has long been assumed that lifespan and healthspan correlate strongly, yet the two can be clearly dissociated1-6. Although there has been a global increase in human life expectancy, increasing longevity is rarely accompanied by an extended healthspan4,7. Thus, understanding the origin of healthy behaviours in old people remains an important and challenging task. Here we report a conserved epigenetic mechanism underlying healthy ageing. Through genome-wide RNA-interference-based screening of genes that regulate behavioural deterioration in ageing Caenorhabditis elegans, we identify 59 genes as potential modulators of the rate of age-related behavioural deterioration. Among these modulators, we found that a neuronal epigenetic reader, BAZ-2, and a neuronal histone 3 lysine 9 methyltransferase, SET-6, accelerate behavioural deterioration in C. elegans by reducing mitochondrial function, repressing the expression of nuclear-encoded mitochondrial proteins. This mechanism is conserved in cultured mouse neurons and human cells. Examination of human databases8,9 shows that expression of the human orthologues of these C. elegans regulators, BAZ2B and EHMT1, in the frontal cortex increases with age and correlates positively with the progression of Alzheimer's disease. Furthermore, ablation of Baz2b, the mouse orthologue of BAZ-2, attenuates age-dependent body-weight gain and prevents cognitive decline in ageing mice. Thus our genome-wide RNA-interference screen in C. elegans has unravelled conserved epigenetic negative regulators of ageing, suggesting possible ways to achieve healthy ageing.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Epigênese Genética , Envelhecimento Saudável/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fatores Genéricos de Transcrição/metabolismo , Envelhecimento/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Cognição , Disfunção Cognitiva , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Histonas/metabolismo , Humanos , Longevidade/genética , Lisina/metabolismo , Masculino , Memória , Metilação , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteínas/genética , Interferência de RNA , Aprendizagem Espacial , Fatores Genéricos de Transcrição/deficiência , Fatores Genéricos de Transcrição/genética
7.
EMBO Rep ; 24(10): e57101, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37621232

RESUMO

The NLR family pyrin domain containing 3 (NLRP3) inflammasome plays an important role in the pathogenesis of a wide variety of human diseases. So far, drugs directly and specifically targeting the NLRP3 inflammasome are not available for clinical use since the safety and efficacy of new compounds are often unclear. A promising approach is thus to identify NLRP3 inhibitors from existing drugs that are already in clinical use. Here, we show that mefloquine, a well-known antimalarial drug, is a highly selective and potent NLRP3 inhibitor by screening a FDA-approved drug library. Mechanistically, mefloquine directly binds to the NLRP3 NACHT and LRR domains to prevent NLRP3 inflammasome activation. More importantly, mefloquine treatment attenuates the symptoms of lipopolysaccharide-induced systemic inflammation and Parkinson's disease-like neural damage in mice. Our findings identify mefloquine as a potential therapeutic agent for NLRP3-driven diseases and migth expand its clinical use considerably.

8.
Proc Natl Acad Sci U S A ; 119(19): e2116380119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35500124

RESUMO

SignificanceThere is a common consensus that lode gold deposits mostly precipitated from metamorphic fluids via fluid boiling and/or fluid-rock interaction, but whether magmatic hydrothermal fluids and the mixing of such fluids with an external component have played a vital role in the formation of lode gold deposits remains elusive. We use garnet secondary ion mass spectrometry oxygen isotope analysis to demonstrate that the world-class Dongping lode gold deposit has been formed by multiple pulses of magmatic hydrothermal fluids and their mixing with large volumes of meteoric water. This study opens an opportunity to tightly constrain the origin of lode gold deposits worldwide and other hydrothermal systems that may have generated giant ore deposits in the Earth's crust.

9.
J Neurosci ; 43(49): 8547-8561, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37802656

RESUMO

Dysfunctional gene expression in nociceptive pathways plays a critical role in the development and maintenance of neuropathic pain. Super enhancers (SEs), composed of a large cluster of transcriptional enhancers, are emerging as new players in the regulation of gene expression. However, whether SEs participate in nociceptive responses remains unknown. Here, we report a spinal-specific SE (SS-SE) that regulates chronic constriction injury (CCI)-induced neuropathic pain by driving Ntmt1 and Prrx2 transcription in dorsal horn neurons. Peripheral nerve injury significantly enhanced the activity of SS-SE and increased the expression of NTMT1 and PRRX2 in the dorsal horn of male mice in a bromodomain-containing protein 4 (BRD4)-dependent manner. Both intrathecal administration of a pharmacological BRD4 inhibitor JQ1 and CRISPR-Cas9-mediated SE deletion abolished the increased NTMT1 and PRRX2 in CCI mice and attenuated their nociceptive hypersensitivities. Furthermore, knocking down Ntmt1 or Prrx2 with siRNA suppressed the injury-induced elevation of phosphorylated extracellular-signal-regulated kinase (p-ERK) and glial fibrillary acidic protein (GFAP) expression in the dorsal horn and alleviated neuropathic pain behaviors. Mimicking the increase in spinal Ntmt1 or Prrx2 in naive mice increased p-ERK and GFAP expression and led to the genesis of neuropathic pain-like behavior. These results redefine our understanding of the regulation of pain-related genes and demonstrate that BRD4-driven increases in SS-SE activity is responsible for the genesis of neuropathic pain through the governance of NTMT1 and PRRX2 expression in dorsal horn neurons. Our findings highlight the therapeutic potential of BRD4 inhibitors for the treatment of neuropathic pain.SIGNIFICANCE STATEMENT SEs drive gene expression by recruiting master transcription factors, cofactors, and RNA polymerase, but their role in the development of neuropathic pain remains unknown. Here, we report that the activity of an SS-SE, located upstream of the genes Ntmt1 and Prrx2, was elevated in the dorsal horn of mice with neuropathic pain. SS-SE contributes to the genesis of neuropathic pain by driving expression of Ntmt1 and Prrx2 Both inhibition of SS-SE with a pharmacological BRD4 inhibitor and genetic deletion of SS-SE attenuated pain hypersensitivities. This study suggests an effective and novel therapeutic strategy for neuropathic pain.


Assuntos
Hipersensibilidade , Neuralgia , Ratos , Masculino , Camundongos , Animais , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Hiperalgesia/metabolismo , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neuralgia/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hipersensibilidade/metabolismo
10.
J Am Chem Soc ; 146(18): 12864-12876, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38670931

RESUMO

Deep-ultraviolet (DUV) light sources are technologically highly important, but DUV light-emitting materials are extremely rare; AlN and its alloys are the only materials known so far, significantly limiting the chemical and structural spaces for materials design. Here, we perform a high-throughput computational search for DUV light emitters based on a set of carefully designed screening criteria relating to the sophisticated electronic structure. In this way, we successfully identify 5 promising material candidates that exhibit comparable or higher radiative recombination coefficients than AlN, including BeGeN2, Mg3NF3, KCaBr3, KHS, and RbHS. Further, we unveil the unique features in the atomic and electronic structures of DUV light emitters and elucidate the fundamental genetic reasons why DUV light emitters are extremely rare. Our study not only guides the design and synthesis of efficient DUV light emitters but also establishes the genetic nature of ultrawide-band-gap semiconductors in general.

11.
Apoptosis ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110356

RESUMO

High-altitude pulmonary edema (HAPE) is a fatal threat for sojourners who ascend rapidly without sufficient acclimatization. Acclimatized sojourners and adapted natives are both insensitive to HAPE but have different physiological traits and molecular bases. In this study, based on GSE52209, the gene expression profiles of HAPE patients were compared with those of acclimatized sojourners and adapted natives, with the common and divergent differentially expressed genes (DEGs) and their hub genes identified, respectively. Bioinformatic methodologies for functional enrichment analysis, immune infiltration, diagnostic model construction, competing endogenous RNA (ceRNA) analysis and drug prediction were performed to detect potential biological functions and molecular mechanisms. Next, an array of in vivo experiments in a HAPE rat model and in vitro experiments in HUVECs were conducted to verify the results of the bioinformatic analysis. The enriched pathways of DEGs and immune landscapes for HAPE were significantly different between sojourners and natives, and the common DEGs were enriched mainly in the pathways of development and immunity. Nomograms revealed that the upregulation of TNF-α and downregulation of RPLP0 exhibited high diagnostic efficiency for HAPE in both sojourners and natives, which was further validated in the HAPE rat model. The addition of TNF-α and RPLP0 knockdown activated apoptosis signaling in endothelial cells (ECs) and enhanced endothelial permeability. In conclusion, TNF-α and RPLP0 are shared biomarkers and molecular bases for HAPE susceptibility during the acclimatization/adaptation/maladaptation processes in sojourners and natives, inspiring new ideas for predicting and treating HAPE.

12.
Br J Haematol ; 204(5): 1830-1837, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38356434

RESUMO

Idiopathic multicentric Castleman disease (iMCD) is subclassified into iMCD-thrombocytopenia, anasarca, reticulin fibrosis, renal dysfunction, organomegaly (TAFRO) and iMCD-not otherwise specified (NOS) according to the Castleman Disease Collaborative Network (CDCN) consensus criteria. With a deeper understanding of iMCD, a group of patients with iMCD-NOS characterised by polyclonal hypergammaglobulinaemia, plasmacytic/mixed-type lymph node histopathology and thrombocytosis has attracted attention. This group of patients has been previously described as having idiopathic plasmacytic lymphadenopathy (IPL). Whether these patients should be excluded from the current classification system lacks sufficient evidence. This retrospective analysis of 228 patients with iMCD-NOS identified 103 (45.2%) patients with iMCD-IPL. The clinical features and outcomes of patients with iMCD-IPL and iMCD-NOS without IPL were compared. Patients with iMCD-IPL showed a significantly higher inflammatory state but longer overall survival. No significant difference in overall survival was observed between severe and non-severe patients in the iMCD-IPL group according to the CDCN severity classification. Compared with lymphoma-like treatments, multiple myeloma-like and IL-6-blocking treatment approaches in the iMCD-IPL group resulted in significantly higher response rates and longer time to the next treatment. These findings highlight the particularities of iMCD-IPL and suggest that it should be considered a new subtype of iMCD-NOS.


Assuntos
Hiperplasia do Linfonodo Gigante , Linfadenopatia , Humanos , Hiperplasia do Linfonodo Gigante/patologia , Hiperplasia do Linfonodo Gigante/mortalidade , Hiperplasia do Linfonodo Gigante/classificação , Hiperplasia do Linfonodo Gigante/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Idoso , Linfadenopatia/patologia , Linfadenopatia/etiologia , Plasmócitos/patologia
13.
Lancet ; 401(10380): 917-927, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36842439

RESUMO

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Masculino , Humanos , Feminino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Recidiva Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Hemorragia
14.
J Gene Med ; 26(1): e3570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37482968

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer with limited treatment options. The PI3K/AKT/mTOR pathway is commonly activated in PDAC and plays a critical role in its progression. METHODS AND RESULTS: In this study, the effect of taselisib (a selective PI3K inhibitor) on PDAC cell proliferation was investigated, and a significant decrease in viability was observed with increasing concentrations of taselisib. Differential analysis on samples from the Genotype-Tissue Expression and The Cancer Genome Atlas databases revealed 24 dysregulated PI3K/AKT/mTOR pathway-related genes (PRGs). Unsupervised clustering-based analysis of transcriptome cohorts revealed two clusters with high consistency between RNA-seq and microarray cohorts. Cluster B had higher enrichment of immune cells, particularly CD8+ T cells, and lower levels of immunosuppressive Treg cells. Moreover, we investigated the relationship between drug sensitivity and different clusters and found that cluster A had a better response to PI3K/AKT/mTOR pathway-related inhibitors and chemotherapy. Finally, cluster A exhibited significant activation of PI3K/AKT/mTOR and related oncogenic pathways, contributing to poor prognosis. The study also developed a risk score based on the expression profiles of PRGs and machine learning, which showed a significant increase in overall survival time among patients in the low-risk group. Importantly, the PI3K/AKT/mTOR pathway could be used to better predict individual risk scores, as evidenced by stratified survival analysis. CONCLUSIONS: These findings suggest that targeting the PI3K/AKT/mTOR pathway may have therapeutic potential in PDAC, and distinct pathway states, immune modulation and tumor microenvironments have prognostic value.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transcriptoma , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células/genética , Microambiente Tumoral
15.
J Gene Med ; 26(6): e3693, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38860366

RESUMO

BACKGROUND: Liver cancer is typified by a complex inflammatory tumor microenvironment, where an array of cytokines and stromal cells orchestrate a milieu that significantly influences tumorigenesis. Interleukin-17A (IL-17A), a pivotal pro-inflammatory cytokine predominantly secreted by Th17 cells, is known to play a substantial role in the etiology and progression of liver cancer. However, the precise mechanism by which IL-17A engages with hepatic stellate cells (HSCs) to facilitate the development of hepatocellular carcinoma (HCC) remains to be fully elucidated. This investigation seeks to unravel the interplay between IL-17A and HSCs in the context of HCC. METHODS: An HCC model was established in male Sprague-Dawley rats using diethylnitrosamine to explore the roles of IL-17A and HSCs in HCC pathogenesis. In vivo overexpression of Il17a was achieved using adeno-associated virus. A suite of molecular techniques, including RT-qPCR, enzyme-linked immunosorbent assays, Western blotting, cell counting kit-8 assays and colony formation assays, was employed for in vitro analyses. RESULTS: The study findings indicate that IL-17A is a key mediator in HCC promotion, primarily through the activation of hepatic progenitor cells (HPCs). This pro-tumorigenic influence appears to be mediated by HSCs, rather than through a direct effect on HPCs. Notably, IL-17A-induced expression of fibroblast activation protein (FAP) in HSCs emerged as a critical factor in HCC progression. Silencing Fap in IL-17A-stimulated HSCs was observed to reverse the HCC-promoting effects of HSCs. CONCLUSIONS: The collective evidence from this study implicates the IL-17A/FAP signaling axis within HSCs as a contributor to HCC development by enhancing HPC activation. These findings bolster the potential of IL-17A as a diagnostic and preventative target for HCC, offering new avenues for therapeutic intervention.


Assuntos
Carcinoma Hepatocelular , Células Estreladas do Fígado , Interleucina-17 , Neoplasias Hepáticas , Animais , Humanos , Masculino , Ratos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Endopeptidases/metabolismo , Endopeptidases/genética , Regulação Neoplásica da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Interleucina-17/metabolismo , Interleucina-17/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Ratos Sprague-Dawley , Microambiente Tumoral
16.
J Neuroinflammation ; 21(1): 81, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566081

RESUMO

BACKGROUND: Senescent astrocytes play crucial roles in age-associated neurodegenerative diseases, including Parkinson's disease (PD). Metformin, a drug widely used for treating diabetes, exerts longevity effects and neuroprotective activities. However, its effect on astrocyte senescence in PD remains to be defined. METHODS: Long culture-induced replicative senescence model and 1-methyl-4-phenylpyridinium/α-synuclein aggregate-induced premature senescence model, and a mouse model of PD were used to investigate the effect of metformin on astrocyte senescence in vivo and in vitro. Immunofluorescence staining and flow cytometric analyses were performed to evaluate the mitochondrial function. We stereotactically injected AAV carrying GFAP-promoter-cGAS-shRNA to mouse substantia nigra pars compacta regions to specifically reduce astrocytic cGAS expression to clarify the potential molecular mechanism by which metformin inhibited the astrocyte senescence in PD. RESULTS: We showed that metformin inhibited the astrocyte senescence in vitro and in PD mice. Mechanistically, metformin normalized mitochondrial function to reduce mitochondrial DNA release through mitofusin 2 (Mfn2), leading to inactivation of cGAS-STING, which delayed astrocyte senescence and prevented neurodegeneration. Mfn2 overexpression in astrocytes reversed the inhibitory role of metformin in cGAS-STING activation and astrocyte senescence. More importantly, metformin ameliorated dopamine neuron injury and behavioral deficits in mice by reducing the accumulation of senescent astrocytes via inhibition of astrocytic cGAS activation. Deletion of astrocytic cGAS abolished the suppressive effects of metformin on astrocyte senescence and neurodegeneration. CONCLUSIONS: This work reveals that metformin delays astrocyte senescence via inhibiting astrocytic Mfn2-cGAS activation and suggest that metformin is a promising therapeutic agent for age-associated neurodegenerative diseases.


Assuntos
Metformina , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Astrócitos/metabolismo , Neurônios Dopaminérgicos , Nucleotidiltransferases/metabolismo , Mitocôndrias/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/farmacologia
17.
Small ; 20(13): e2307067, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37972263

RESUMO

This work proposes the concept of single-cell microRNA (miR) therapy and proof-of-concept by engineering a nanopipette for high-precision miR-21-targeted therapy in a single HeLa cell with sensitive photoelectrochemical (PEC) feedback. Targeting the representative oncogenic miR-21, the as-functionalized nanopipette permits direct intracellular drug administration with precisely controllable dosages, and the corresponding therapeutic effects can be sensitively transduced by a PEC sensing interface that selectively responds to the indicator level of cytosolic caspase-3. The experimental results reveal that injection of ca. 4.4 × 10-20 mol miR-21 inhibitor, i.e., 26488 copies, can cause the obvious therapeutic action in the targeted cell. This work features a solution to obtain the accurate knowledge of how a certain miR-drug with specific dosages treats the cells and thus provides an insight into futuristic high-precision clinical miR therapy using personalized medicine, provided that the prerequisite single-cell experiments are courses of personalized customization.


Assuntos
MicroRNAs , Humanos , Células HeLa , Retroalimentação , Medicina de Precisão
18.
Small ; : e2402841, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693072

RESUMO

Developing lightweight composite with reversible switching between microwave (MW) absorption and electromagnetic interference (EMI) shielding is promising yet remains highly challenging due to the completely inconsistent attenuation mechanism for electromagnetic (EM) radiation. Here, a lightweight vanadium dioxide/expanded polymer microsphere composites foam (VO2/EPM) is designed and fabricated with porous structures and 3D VO2 interconnection, which possesses reversible switching function between MW absorption and EMI shielding under thermal stimulation. The VO2/EPM exhibits MW absorption with a broad effective absorption bandwidth of 3.25 GHz at room temperature (25 °C), while provides EMI shielding of 23.1 dB at moderately high temperature (100 °C). This reversible switching performance relies on the porous structure and tunability of electrical conductivity, complex permittivity, and impedance matching, which are substantially induced by the convertible crystal structure and electronic structure of VO2. Finite element simulation is employed to qualitatively investigate the change in interaction between EM waves and VO2/EPM before and after the phase transition. Moreover, the application of VO2/EPM is demonstrated with a reversible switching function in controlling wireless transmission on/off, showcasing its excellent cycling stability. This kind of smart material with a reversible switching function shows great potential in next-generation electronic devices.

19.
Ann Surg Oncol ; 31(6): 3819-3829, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38245646

RESUMO

BACKGROUND: The impact of changes in skeletal muscle and sarcopenia on outcomes during neoadjuvant chemoradiotherapy (NACR) for patients with esophageal cancer remains controversial. PATIENTS AND METHODS: We retrospectively analyzed the data of patients with locally advanced esophageal squamous cell cancer who received NACR followed by esophagectomy between June 2013 and December 2021. The images at third lumbar vertebra were analyzed to measure the cross-sectional area and calculate skeletal muscle index (SMI) before and after NACR. SMI less than 52.4 cm2/m2 for men and less than 38.5 cm2/m2 for women were defined as sarcopenia. The nonlinearity of the effect of percent changes in SMI (ΔSMI%) to survival outcomes was assessed by restricted cubic splines. RESULTS: Overall, data of 367 patients were analyzed. The survival outcomes between sarcopenia and non-sarcopenia groups had no significant differences before NACR. However, patients in post-NACR sarcopenia group showed poor overall survival (OS) benefit (P = 0.016) and poor disease-free survival (DFS) (P = 0.043). Severe postoperative complication rates were 11.9% in post-NACR sarcopenia group and 5.0% in post-NACR non-sarcopenia group (P = 0.019). There was a significant non-linear relationship between ΔSMI% and survival outcomes (P < 0.05 for non-linear). On the multivariable analysis of OS, ΔSMI% > 12% was the independent prognostic factor (HR 1.76, 95% CI 1.03-2.99, P = 0.039) and significant difference was also found on DFS analysis (P = 0.025). CONCLUSIONS: Patients with post-neoadjuvant chemoradiotherapy sarcopenia have worse survival and adverse short-term outcomes. Moreover, greater loss in SMI is associated with increased risks of death and disease progression during neoadjuvant chemoradiotherapy, with maximum impact noted with SMI loss greater than 12%.


Assuntos
Neoplasias Esofágicas , Esofagectomia , Músculo Esquelético , Terapia Neoadjuvante , Sarcopenia , Humanos , Sarcopenia/etiologia , Sarcopenia/patologia , Masculino , Feminino , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/complicações , Terapia Neoadjuvante/mortalidade , Estudos Retrospectivos , Pessoa de Meia-Idade , Taxa de Sobrevida , Músculo Esquelético/patologia , Prognóstico , Idoso , Seguimentos , Quimiorradioterapia/mortalidade , Quimiorradioterapia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Quimiorradioterapia Adjuvante
20.
Drug Metab Dispos ; 52(3): 210-217, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38195521

RESUMO

Valproic acid (VPA) is a first-line antiepileptic drug with broad efficacy. Due to significant individual differences in its metabolism, therapeutic drug monitoring is commonly used. However, the recommended therapeutic range (50-100 µg/mL) is inadequate for predicting clinical outcomes. Additionally, the relationship between VPA metabolites and clinical outcomes remains unclear. In this retrospective study, 485 Chinese Southern Han epilepsy patients receiving VPA monotherapy were analyzed after reaching steady-state levels. Plasma concentrations of VPA and its five main metabolites were determined by liquid chromatography-mass spectrometry (LC-MS). We assessed the relevance of the recommended therapeutic VPA range for clinical outcomes and explored the association between VPA/metabolites levels and treatment efficacy/adverse effects. Vitro experiments were conducted to assess 4-ene-VPA hepatotoxicity. The therapeutic range of VPA exhibited no significant correlation with clinical outcomes, and plasma concentrations of VPA failed to serve as predictive indicators for treatment response/adverse effects. Treatment responders had higher 2-PGA concentrations (median, 26.39 ng/mL versus 13.68 ng/mL), with a threshold of 36.5 ng/mL for optimal epilepsy treatment. Patients with abnormal liver function had a higher 4-ene-VPA median concentration (6.41 µg/mL versus 4.83 µg/mL), and the ratio of 4-ene-VPA to VPA better predicted VPA-induced hepatotoxicity (area under the curve, 0.718) than 4-ene-VPA concentration. Vitro experiments revealed that 4-ene-VPA was more hepatotoxic than VPA in HepaRG and L02 cell lines. Total plasma VPA concentration does not serve as a predictor of clinical outcomes. 2-PGA concentrations may be associated with efficacy, whereas the ratio of 4-ene-VPA to VPA may be considered a better biomarker (threshold 10.03%) for VPA-induced hepatotoxicity. SIGNIFICANCE STATEMENT: This was the first and largest observational cohort in China to explore the relationship between patients' parent and metabolites concentrations of VPA and clinical outcomes during the maintenance of VPA monotherapy in epileptic patients. This study provided feasible references of VPA for epilepsy clinical treatment with a larger sample of patients compared with previous studies for a more definitive conclusion based on real-world situations. We found two potential biomarkers in predicting efficacy and liver injury, respectively. This breakthrough has the potential to assist in the rational use of VPA.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Epilepsia , Humanos , Anticonvulsivantes/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Monitoramento de Medicamentos , Epilepsia/tratamento farmacológico , Estudos Retrospectivos , Ácido Valproico/efeitos adversos
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