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1.
Am J Pathol ; 194(7): 1248-1261, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38599461

RESUMO

Mucosal-associated invariant T (MAIT) cells are essential in defending against infection. Sepsis is a systemic inflammatory response to infection and a leading cause of death. The relationship between the overall competency of the host immune response and disease severity is not fully elucidated. This study identified a higher proportion of circulating MAIT17 with expression of IL-17A and retinoic acid receptor-related orphan receptor γt in patients with sepsis. The proportion of MAIT17 was correlated with the severity of sepsis. Single-cell RNA-sequencing analysis revealed an enhanced expression of lactate dehydrogenase A (LDHA) in MAIT17 in patients with sepsis. Cell-culture experiments demonstrated that phosphoinositide 3-kinase-LDHA signaling was required for retinoic acid receptor-related orphan receptor γt expression in MAIT17. Finally, the elevated levels of plasma IL-18 promoted the differentiation of circulating MAIT17 cells in sepsis. In summary, this study reveals a new role of circulating MAIT17 in promoting sepsis severity and suggests the phosphoinositide 3-kinase-LDHA signaling as a driving force in MAIT17 responses.


Assuntos
Diferenciação Celular , Células T Invariantes Associadas à Mucosa , Sepse , Humanos , Sepse/imunologia , Sepse/patologia , Sepse/sangue , Células T Invariantes Associadas à Mucosa/imunologia , Células T Invariantes Associadas à Mucosa/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Idoso , Interleucina-17/metabolismo , Interleucina-17/sangue , Transdução de Sinais , Fosfatidilinositol 3-Quinases/metabolismo
2.
FASEB J ; 38(13): e23749, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38953707

RESUMO

Pulmonary fibrosis is a formidable challenge in chronic and age-related lung diseases. Myofibroblasts secrete large amounts of extracellular matrix and induce pro-repair responses during normal wound healing. Successful tissue repair results in termination of myofibroblast activity via apoptosis; however, some myofibroblasts exhibit a senescent phenotype and escape apoptosis, causing over-repair that is characterized by pathological fibrotic scarring. Therefore, the removal of senescent myofibroblasts using senolytics is an important method for the treatment of pulmonary fibrosis. Procyanidin C1 (PCC1) has recently been discovered as a senolytic compound with very low toxicity and few side effects. This study aimed to determine whether PCC1 could improve lung fibrosis by promoting apoptosis in senescent myofibroblasts and to investigate the mechanisms involved. The results showed that PCC1 attenuates bleomycin (BLM)-induced pulmonary fibrosis in mice. In addition, we found that PCC1 inhibited extracellular matrix deposition and promoted the apoptosis of senescent myofibroblasts by increasing PUMA expression and activating the BAX signaling pathway. Our findings represent a new method of pulmonary fibrosis management and emphasize the potential of PCC1 as a senotherapeutic agent for the treatment of pulmonary fibrosis, providing hope for patients with pulmonary fibrosis worldwide. Our results advance our understanding of age-related diseases and highlight the importance of addressing cellular senescence in treatment.


Assuntos
Bleomicina , Catequina , Senescência Celular , Camundongos Endogâmicos C57BL , Miofibroblastos , Fibrose Pulmonar , Animais , Bleomicina/toxicidade , Miofibroblastos/metabolismo , Miofibroblastos/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Camundongos , Senescência Celular/efeitos dos fármacos , Catequina/farmacologia , Catequina/análogos & derivados , Proantocianidinas/farmacologia , Apoptose/efeitos dos fármacos , Masculino , Biflavonoides/farmacologia , Transdução de Sinais/efeitos dos fármacos
3.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37991273

RESUMO

Prolonged exposure to others' suffering can lead to empathy fatigue, especially when individuals struggle to effectively regulate their empathic capacity. Shifting active attention away from emotional components toward cognitive components of others' suffering is an effective strategy for mitigating empathy fatigue. This research investigated how top-down attentional manipulation modulates empathy fatigue in both auditory (Study 1) and visual (Study 2) modalities. Participants completed two tasks in both studies: (i) the attention to cognitive empathy task (A-C task) and (ii) the attention to emotional empathy task (A-E task). Each task included three blocks (Time Block 1, Time Block 2, and Time Block 3) designed to induce empathy fatigue. Study 1 revealed that the A-C task reduced empathy fatigue and N1 amplitudes than the A-E task in Time Block 3, indicating that attention to cognitive empathy might decrease auditory empathy fatigue. Study 2 indicates that the A-C task caused a longer N2 latency than the A-E task, signifying a decelerated emotional empathic response when attention was on cognitive empathy in the visual modality. Overall, prioritizing cognitive empathy seems to conserve mental resources and reduce empathy fatigue. This research documented the relationship between top-down attention and empathy fatigue and the possible neural mechanism.


Assuntos
Emoções , Empatia , Humanos , Emoções/fisiologia
4.
Genomics ; 116(2): 110814, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38432499

RESUMO

Lactate is a glycolysis end product, and its levels are markedly associated with disease severity, morbidity, and mortality in sepsis. It modulates key functions of immune cells, including macrophages. In this investigation, transcriptomic analysis was performed using lactic acid, sodium lactate, and hydrochloric acid-stimulated mouse bone marrow-derived macrophages (iBMDM), respectively, to identify lactate-associated signaling pathways. After 24 h of stimulation, 896 differentially expressed genes (DEG) indicated were up-regulation, whereas 792 were down-regulated in the lactic acid group, in the sodium lactate group, 128 DEG were up-regulated, and 41 were down-regulated, and in the hydrochloric acid group, 499 DEG were up-regulated, and 285 were down-regulated. Subsequently, clinical samples were used to further verify the eight genes with significant differences, among which Tssk6, Ypel4, Elovl3, Trp53inp1, and Cfp were differentially expressed in patients with high lactic acid, indicating their possible involvement in lactic acid-induced inflammation and various physiological diseases caused by sepsis. However, elongation of very long chain fatty acids protein 3 (Elovl3) was negatively correlated with lactic acid content in patients. The results of this study provide a necessary reference for better understanding the transcriptomic changes caused by lactic acid and explain the potential role of high lactic acid in the regulation of macrophages in sepsis.


Assuntos
Ácido Láctico , Sepse , Animais , Camundongos , Humanos , Ácido Láctico/metabolismo , Ácido Láctico/farmacologia , Lactato de Sódio , RNA Mensageiro , Ácido Clorídrico , Sepse/genética , Sepse/metabolismo , Macrófagos/metabolismo
5.
Nano Lett ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39401161

RESUMO

Scaling up quantum dots to two-dimensional (2D) arrays is a crucial step for advancing semiconductor quantum computation. However, maintaining excellent tunability of quantum dot parameters, including both nearest-neighbor and next-nearest-neighbor couplings, during 2D scaling is challenging, particularly for silicon quantum dots due to their relatively small size. Here, we present a highly controllable and interconnected 2D quantum dot array in planar silicon, demonstrating independent control over electron fillings and the tunnel couplings of nearest-neighbor dots. More importantly, we also demonstrate the wide tuning of tunnel couplings between next-nearest-neighbor dots, which play a crucial role in 2D quantum dot arrays. This excellent tunability enables us to alter the coupling configuration of the array as needed. These results open up the possibility of utilizing silicon quantum dot arrays as versatile platforms for quantum computing and quantum simulation.

6.
J Am Chem Soc ; 146(33): 23412-23416, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39134058

RESUMO

The preparation of coordination polymer (CP) alloys is demonstrated by the use of two meltable, one-dimensional crystal structures via melt-kneading. The polymer structures of the alloys are studied by synchrotron X-ray absorption and scattering, solid-state NMR spectroscopy, DSC, and viscoelastic measurements. Crystalline and amorphous domains and thermal properties (melting and glass transition) in the alloys depend on the ratio of the two constituent CPs. The glassy alloy composed of an equivalent amount of two CPs shows high plastic deformation properties, and the fracture point reaches 128% without a filler or compatibilizing agent, hence behaving as ductile materials.

7.
J Am Chem Soc ; 146(6): 4153-4161, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300827

RESUMO

Separating ethane (C2H6) from ethylene (C2H4) is an essential and energy-intensive process in the chemical industry. Here, we report two flexible diamondoid coordination networks, X-dia-1-Ni and X-dia-1-Ni0.89Co0.11, that exhibit gate-opening between narrow-pore (NP) and large-pore (LP) phases for C2H6, but not for C2H4. X-dia-1-Ni0.89Co0.11 thereby exhibited a type F-IV isotherm at 273 K with no C2H6 uptake and a high uptake (111 cm3 g-1, 1 atm) for the NP and LP phases, respectively. Conversely, the LP phase exhibited a low uptake of C2H4 (12.2 cm3 g-1). This C2H6/C2H4 uptake ratio of 9.1 for X-dia-1-Ni0.89Co0.11 far surpassed those of previously reported physisorbents, many of which are C2H4-selective. In situ variable-pressure X-ray diffraction and modeling studies provided insight into the abrupt C2H6-induced structural NP to LP transformation. The promise of pure gas isotherms and, more generally, flexible coordination networks for gas separations was validated by dynamic breakthrough studies, which afforded high-purity (99.9%) C2H4 in one step.

8.
Small ; : e2406377, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370574

RESUMO

The production of bacterial toxins and excessive accumulation of reactive oxygen species (ROS) can induce localized oxidative stress, triggering an exaggerated immune response that impedes wound healing and culminates in chronic wounds. To address this issue, a microneedle (MN) system loaded with copper-manganese oxide (CMO) is developed to modulate the hyperimmune response in wounds. CMO@MN exhibits excellent antimicrobial and anti-inflammatory properties by effectively killing bacteria, scavenging ROS, and modulating macrophage polarization through their multiple enzymatic activities and photothermal properties. RNA sequencing revealed that CMO@MN improved the therapeutic effect on the infected skin of mice by balancing the ratio of M1/M2 macrophages and promoting cell migration and angiogenesis through the regulation of relevant pathways. Overall, this CMO@MN patch skillfully balances the complex issues between the immune response and wound healing and has potential applications in the treatment of other serious bacterial infections.

9.
Langmuir ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141493

RESUMO

The adsorbed nanobubbles inside the nanochannels can cause fluid transport blockages, which will obviously degrade the nanodevice performance and reduce the lifetime. However, due to small-scale effects, the removal of nanobubbles is a huge challenge at the nanoscale. Herein, molecular dynamics simulations are carried out to study the effect of the electrostatic field on underwater nitrogen nanobubbles confined in nanochannels. It is found that the nanobubbles will collapse under an appropriate electrostatic field, thereby unblocking the transport of water in the nanochannels. The formation of ordered water structures induced by electrostatic fields plays an important role in the removal of nanobubbles from the nanochannels. Our findings provide a convenient, controllable, and remote way to address the blockage problem of nanobubbles in nanochannels, which may have potential applications in improving the performance of fuel cells.

10.
Environ Sci Technol ; 58(25): 11140-11151, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38867458

RESUMO

Microplastic records from lake cores can reconstruct the plastic pollution history. However, the associations between anthropogenic activities and microplastic accumulation are not well understood. Huguangyan Maar Lake (HML) is a deep-enclosed lake without inlets and outlets, where the sedimentary environment is ideal for preserving a stable and historical microplastic record. Microplastic (size: 10-500 µm) characteristics in the HML core were identified using the Laser Direct Infrared Imaging system. The earliest detectable microplastics appeared unit in 1955 (1.1 items g-1). The microplastic abundance ranged from n.d. to 615.2 items g-1 in 1955-2019 with an average of 134.9 items g-1. The abundance declined slightly during the 1970s and then increased rapidly after China's Reform and Opening Up in 1978. Sixteen polymer types were detectable, with polyethylene and polypropylene dominating, accounting for 23.5 and 23.3% of the total abundance, and the size at 10-100 µm accounted for 80%. Socioeconomic factors dominated the microplastic accumulation based on the random forest modeling, and the contributions of GDP per capita, plastic-related industry yield, and total crop yield were, respectively, 13.9, 35.1, and 9.3% between 1955-2019. The total crop yield contribution further increased by 1.7% after 1978. Coarse sediment particles increased with soil erosion exacerbated microplastics discharging into the sediment.


Assuntos
Monitoramento Ambiental , Lagos , Microplásticos , China , Microplásticos/análise , Poluentes Químicos da Água/análise , Plásticos , Sedimentos Geológicos/química
11.
J Asthma ; : 1-13, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39394937

RESUMO

OBJECTIVE: This meta-analysis aims to evaluate the efficacy and safety of montelukast combined with levocetirizine in the treatment of allergic rhinitis with asthma, and to provide objective and effective evidence-based medical evidence for clinical use. DATA SOURCES: Pubmed, Web of Science, Cochrane Library, WANFANG DATA, CNKI, and Chinese BioMedical Literature Database were retrieved to identify records related to Montelukast combined with levocetirizine in the treatment of allergic rhinitis with asthma. STUDY SELECTIONS: First, the eligibility criteria were employed to screen search results. Then, two investigators independently assessed titles, abstracts, and the full text of all retrieved references to identify potentially eligible studies. RESULTS: As of 2024-02-03, a total of 6 articles were included in this meta-analysis, covering 2950 patients with allergic rhinitis with asthma. The meta-analysis results exhibited a pooled NSS of -1.28 (95%CI: -1.64 to -0.92), suggesting that the combination of montelukast and levocetirizine was effective in the treatment of nasal symptoms of allergic rhinitis complicated with asthma. The meta-analysis of controlled trials showed that the SMD of NSS in the group of Montelukast combined with levocetirizine was -2.56 (95%CI: -2.77 to -2.35). The result indicated that compared with the control group, the combination of montelukast with levocetirizine significantly improved the symptoms of allergic rhinitis. CONCLUSION: In summary, this meta-analysis demonstrated the efficacy of montelukast combined with levocetirizine in the treatment of nasal symptoms in AR with asthma, indicating that the combination of montelukast with levocetirizine is more effective in improving symptoms of allergic rhinitis than monotherapy and has good safety.

12.
Cereb Cortex ; 33(21): 10802-10812, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37715469

RESUMO

Previous studies have reported relationships between exercise and pain. However, little is known about how aggressive exercise modulates individuals' responses to their own and others' pain. This present study addresses this question by conducting 2 studies employing event-related potential (ERP). Study 1 included 38 participants whose self-perceived pain was assessed after intervention with aggressive or nonaggressive exercises. Study 2 recruited 36 participants whose responses to others' pain were assessed after intervention with aggressive or nonaggressive exercise. Study 1's results showed that P2 amplitudes were smaller, reaction times were longer, and participants' judgments were less accurate in response to self-perceived pain stimuli, especially to high-pain stimuli, after intervention with aggressive exercise compared to nonaggressive exercise. Results of study 2 showed that both P3 and LPP amplitudes to others' pain were larger after intervention with aggressive exercise than with nonaggressive exercise. These results suggest that aggressive exercise decreases individuals' self-perceived pain and increases their empathic responses to others' pain.


Assuntos
Potenciais Evocados , Dor , Humanos , Potenciais Evocados/fisiologia , Empatia , Tempo de Reação , Eletroencefalografia
13.
J Nanobiotechnology ; 22(1): 243, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735927

RESUMO

Hepatocellular carcinoma (HCC) represents one of the deadliest cancers globally, making the search for more effective diagnostic and therapeutic approaches particularly crucial. Aptamer-functionalized nanomaterials (AFNs), an innovative nanotechnology, have paved new pathways for the targeted diagnosis and treatment of HCC. Initially, we outline the epidemiological background of HCC and the current therapeutic challenges. Subsequently, we explore in detail how AFNs enhance diagnostic and therapeutic efficiency and reduce side effects through the specific targeting of HCC cells and the optimization of drug delivery. Furthermore, we address the challenges faced by AFNs in clinical applications and future research directions, with a particular focus on enhancing their biocompatibility and assessing long-term effects. In summary, AFNs represent an avant-garde therapeutic approach, opening new avenues and possibilities for the diagnosis and treatment of HCC.


Assuntos
Aptâmeros de Nucleotídeos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanoestruturas , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Humanos , Aptâmeros de Nucleotídeos/química , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Animais , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia
14.
Cell Mol Life Sci ; 80(10): 308, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37768341

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease characterized by extensive extracellular matrix (ECM) deposition by activated myofibroblasts, which are specialized hyper-contractile cells that promote ECM remodeling and matrix stiffening. New insights on therapeutic strategies aimed at reversing fibrosis by targeting myofibroblast fate are showing promise in promoting fibrosis resolution. Previously, we showed that a novel adipocytokine, omentin-1, attenuated bleomycin (BLM)-induced lung fibrosis by reducing the number of myofibroblasts. Apoptosis, deactivation, and reprogramming of myofibroblasts are important processes in the resolution of fibrosis. Here we report that omentin-1 reverses established lung fibrosis by promoting mechanically activated myofibroblasts dedifferentiation into lipofibroblasts. Omentin-1 promotes myofibroblasts lipogenic differentiation by inhibiting dimerization and nuclear translocation of glycolytic enzymes pyruvate kinase isoform M2 (PKM2) and activation of the downstream Yes-associated protein (YAP) by increasing the cofactor fructose-1,6-bisphosphate (F1, 6BP, FBP). Moreover, omentin-1 activates proliferator-activated receptor gamma (PPARγ) signaling, the master regulator of lipogenesis, and promotes the upregulation of the lipogenic differentiation-related protein perilipin 2 (PLIN2) by suppressing the PKM2-YAP pathway. Ultimately, omentin-1 facilitates myofibroblasts transformation into the lipofibroblast phenotype, with reduced collagen synthesis and enhanced degradation properties, which are crucial mechanisms to clear the ECM deposition in fibrotic tissue, leading to fibrosis resolution. Our results indicate that omentin-1 targets mechanical signal accelerates fibrosis resolution and reverses established lung fibrosis by promoting myofibroblasts lipogenic differentiation, which is closely associated with ECM clearance in fibrotic tissue. These findings suggest that targeting mechanical force to promote myofibroblast lipogenic differentiation is a promising therapeutic strategy against persistent lung fibrosis.


Assuntos
Fibrose Pulmonar Idiopática , PPAR gama , Humanos , PPAR gama/genética , Lipogênese , Fibroblastos , Diferenciação Celular
15.
Hemoglobin ; 48(1): 60-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38314576

RESUMO

Patients with the genotype of ß0/ß0 for ß-thalassemia (ß-thal) usually behave as ß-thal major (ß-TM) phenotype which is transfusion-dependent. The pathophysiology of ß-thal is the imbalance between α/ß-globin chains. The degree of α/ß-globin imbalance can be reduced by the more effective synthesis of γ-globin chains, and increased Hb F levels, modifying clinical severity of ß-TM. We report a Chinese child who had homozygous ß0-thal and a heterozygous KLF1 mutation. The patient had a moderate anemia since 6 months old, keeping a baseline Hb value of 8.0-9.0 g/dL. She had normal development except for a short stature (3rd percentile) until 6 years old, when splenomegaly and facial bone deformities occurred. Although genetic alteration of KLF1 expression in ß0/ß0 patients can result in some degree of disease alleviation, our case shows that it is insufficient to ameliorate satisfactorily the presentation. This point should be borne in mind for physicians who provide the genetic counseling and prenatal diagnosis to at-risk families.


Assuntos
Globinas beta , Talassemia beta , Criança , Feminino , Humanos , Lactente , alfa-Globinas/genética , Globinas beta/genética , Talassemia beta/genética , China , Seguimentos , Genótipo , Mutação
16.
Zhonghua Nan Ke Xue ; 30(6): 493-498, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-39212357

RESUMO

OBJECTIVE: To comprehensively analyze the numbers of involved chromosomes and breakpoints and the clinical phenotypes of the patients with complex chromosome rearrangement (CCR). METHODS: We selected 23 745 patients with abnormal fertility seeking medical care in the Center of Reproductive Medicine of Peking University Third Hospital from 2011 to 2015, and analyzed their peripheral blood chromosomal karyotypes using G-banding, C-banding and fluorescence in situ hybridization (FISH). RESULTS: A total of 28 CCR carriers (0.118%) were detected among the 23 745 patients with abnormal fertility, including 18 males mainly with azoospermia or oligoasthenospermia and 10 females mainly with infertility, recurrent abortion, embryo termination and abnormal birth. Of the 28 cases of CCR, tripartite rearrangement was found in 9 (32.14%), double translocation in 7 (25%) and special translocation in 12 (42.86%). CCR carrier-related chromosomes were all involved but chromosomes 12 and 19, while 2 and 5 were involved most frequently. CONCLUSION: At present, the incidence of CCR is low. CCR carriers with normal phenotypes are often found because of reproductive problems, and their low chance of having a normal baby necessitates the use of preimplantation genetic test to improve the rate of live birth. Due to the diversity of the chromosomes and breakpoints involved in CCR, it is crucial to give each CCR carrier precise genetic counseling.


Assuntos
Hibridização in Situ Fluorescente , Translocação Genética , Humanos , Masculino , Feminino , Aberrações Cromossômicas , Cariotipagem , Adulto , Bandeamento Cromossômico , Azoospermia/genética , Testes Genéticos , Fenótipo , Heterozigoto , Infertilidade/genética
17.
Angew Chem Int Ed Engl ; : e202413962, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39183712

RESUMO

An expanded carbaporphyrinoid analogue, octaphyrin(2,1,1,1,2,1,1,1), containing two rigid diphenylacetylene moieties is reported. In contrast to traditional pyrrolic macrocycles where flexible conformers coexist in dynamic equilibrium, this macrocycle exists as two separable, conformationally stable stereoisomers, denoted as 1A and 1B. The conformational effect of both conformers, as well as their protonated forms, were thoroughly studied using NMR spectroscopy, UV-Vis, and single crystal X-ray diffraction analyses. Importantly, heating conformer 1B leads to its irreversible conversion to 1A, whereas in its protonated form, 1A·2MSA undergoes irreversible transformation to 1B·2MSA at lower temperatures. These temperature-dependent features establish a foundation for developing new accumulated heat sensors, as demonstrated by the use of the present octaphyrins as a customized thermochromic indicator in steam sterilization. The present study thus underscores how the conformational rigidity of these new polypyrrolic macrocycles imparts properties that are distinct from historically flexible expanded porphyrinoids.

18.
J Cell Physiol ; 238(8): 1909-1920, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37357506

RESUMO

Human embryonic stem cells (hESCs) have great potential for developmental biology and regenerative medicine. However, extensive apoptosis often occurs when hESCs respond to various stresses or injuries. Understanding the molecular control and identifying new factors associated with hESC survival are fundamental to ensure the high quality of hESCs. In this study, we report that PRPF8, an RNA spliceosome component, is essential for hESC survival. PRPF8 knockdown (KD) induces p53 protein accumulation and activates the p53 pathway, leading to apoptosis in hESCs. Strikingly, silencing of p53 rescues PRPF8 KD-induced apoptosis, indicating that PRPF8 KD triggers hESC apoptosis through activating the p53 pathway. In search for the mechanism by which p53 pathway is activated by PRPF8 KD, we find that PRPF8 KD alters alternative splicing of many genes, including PIRH2 which encodes an E3 ubiquitin ligase of p53. PIRH2 has several isoforms such as PIRH2A, PIRH2B, and PIRH2C. Intriguingly, PRPF8 KD specifically increases the transcript level of the PIRH2B isoform, which lacks a RING domain and E3 ligase activity. Functionally, PIRH2B KD partially rescues the reduction in cell numbers and upregulation of P21 caused by PRPF8 KD in hESCs. The finding suggests that PRPF8 controls alternative splicing of PIRH2 to maintain the balance of p53 pathway activity and survival of hESCs. The PRPF8/PIRH2/p53 axis identified here provides new insights into how p53 pathway and hESC survival are precisely regulated at multiple layers, highlighting an important role of posttranscriptional machinery in supporting hESC survival.


Assuntos
Processamento Alternativo , Proteína Supressora de Tumor p53 , Humanos , Processamento Alternativo/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
19.
Cogn Affect Behav Neurosci ; 23(3): 620-630, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36702992

RESUMO

Extracting statistical regularities from the environment is crucial for survival. It allows us to learn cues for where and when future events will occur. Can we learn these associations even when the cues are not consciously perceived? Can these unconscious processes integrate information over long periods of time? We show that human visual system can track the probability of location contingency between an unconscious prime and a conscious target over a period of time of minutes. In a series of psychophysical experiments, we adopted an exogenous priming paradigm and manipulated the location contingency between a masked prime and a visible target (i.e., how likely the prime location predicted the target location). The prime's invisibility was verified both subjectively and objectively. Although the participants were unaware of both the existence of the prime and the prime-target contingency, our results showed that the probability of location contingency was tracked and manifested in the subsequent priming effect. When participants were first entrained into the fully predictive prime-target probability, they exhibited faster responses to the more predictive location. On the contrary, when no contingency existed between the prime and target initially, participants later showed faster responses to the less predictive location. These results were replicated in two more experiments with increased statistical power and a fine-grained delineation of prime awareness. Together, we report that the human visual system is capable of tracking unconscious probability over a period of time, demonstrating how implicit and uncertain regularity guides behavior.


Assuntos
Estado de Consciência , Aprendizagem , Humanos , Estado de Consciência/fisiologia , Sinais (Psicologia) , Probabilidade , Conscientização/fisiologia
20.
Toxicol Appl Pharmacol ; 480: 116745, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37931757

RESUMO

The aggregation of misfolded proteins, such as α-synuclein in Parkinson's disease (PD), occurs intracellularly or extracellularly in the majority of neurodegenerative diseases. The immunoproteasome has more potent chymotrypsin-like activity than normal proteasome. Thus, degradation of α-synuclein aggregation via immunoproteasome is an attractive approach for PD drug development. Herein, we aimed to determine if novel compound, 11-Hydroxy-1-(8-methoxy-5-(trifluoromethyl)quinolin-2-yl)undecan-1-one oxime (named as J24335), is a promising candidate for disease-modifying therapy to prevent the pathological progression of neurodegenerative diseases, such as PD. The effects of J24335 on inducible PC12/A53T-α-syn cell viability and cytotoxicity were evaluated by MTT assay and LDH assay, respectively. Evaluation of various proteasome activities was done by measuring the luminescence of enzymatic activity after the addition of different amounts of aminoluciferin. Immunoblotting and real-time PCR were employed to detect the expression of various proteins and genes, respectively. We also used a transgenic mouse model for behavioral testing and immunochemical analysis, to assess the neuroprotective effects of J24335. J24335 inhibited wild-type and mutant α-synuclein aggregation without affecting the growth or death of neuronal cells. The inhibition of α-synuclein aggregation by J24335 was caused by activation of immunoproteasome, as mediated by upregulation of LMP7, and increased cellular chymotrypsin-like activity in 20S proteasome. J24335-enhanced immunoproteasome activity was mediated by PKA/Akt/mTOR pathway activation. Moreover, animal studies revealed that J24335 treatment markedly mitigated both the loss of tyrosine hydroxylase-positive (TH-) neurons and impaired motor skill development. This is the first report to use J24335 as an immunoproteasome enhancing agent to antagonize pathological α-synuclein-mediated neurodegeneration.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Camundongos , Animais , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Quimotripsina/uso terapêutico , Doença de Parkinson/genética , Camundongos Transgênicos , Doenças Neurodegenerativas/tratamento farmacológico , Modelos Animais de Doenças
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