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1.
Front Pharmacol ; 15: 1407525, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39318781

RESUMO

Background: Prostate cancer (PCa) is the most common non-cutaneous malignancy in men globally. Sappan lignum, which exists in the heartwood of Caesalpinia sappan L., has antitumor effects; however, its exact mechanism of action remains unclear. This study elucidated the underlying mechanisms of Sappan lignum in PCa through network pharmacology approaches and molecular docking techniques. Moreover, the therapeutic effects of Sappan lignum on PCa were verified through in vitro experiments. Methods: The constituent ingredients of Sappan lignum were retrieved from the HERB database. Active plant-derived compounds of Sappan lignum were screened based on gastrointestinal absorption and gastric drug properties. Disease targets for PCa were screened using unpaired and paired case datasets from the Gene Expression Omnibus. Intersection targets were used for gene ontology and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Core targets were identified through topological analysis parameters and their clinical relevance was validated through The Cancer Genome Atlas database. The affinity between the phytochemicals of Sappan lignum and core proteins was verified using the molecular docking technique. Validation experiments confirmed the significant potential of Sappan lignum in treating PCa. Results: Twenty-one plant-derived compounds of Sappan lignum and 821 differentially expressed genes associated with PCa were collected. Among 32 intersection targets, 8 were screened according to topological parameters. KEGG analysis indicated that the antitumor effects of Sappan lignum on PCa were primarily associated with the p53 pathway. The molecular docking technique demonstrated a strong affinity between 3-deoxysappanchalcone (3-DSC) and core proteins, particularly cyclin B1 (CCNB1). CCNB1 expression correlated with clinicopathological features in patients with PCa. Experimental results revealed that 3-DSC exhibited anti-proliferative, anti-migratory, and pro-apoptotic effects on 22RV1 and DU145 cells while also causing G2/M phase cell cycle arrest, potentially through modulating the p53/p21/CDC2/CCNB1 pathway. Conclusion: This research highlights the promising therapeutic potential of Sappan lignum in treating PCa, with a particular focus on targeting the p53 pathway.

2.
Sci China Life Sci ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39327392

RESUMO

As the elderly population expands, the pursuit of therapeutics to reduce morbidity and extend lifespan has become increasingly crucial. As an FDA-approved drug for chronic cholestatic liver diseases, tauroursodeoxycholic acid (TUDCA), a natural bile acid, offers additional health benefits beyond liver protection. Here, we show that TUDCA extends the lifespan and healthspan of C. elegans. Importantly, oral supplementation of TUDCA improves fitness in old mice, including clinically relevant phenotypes, exercise capacity and cognitive function. Consistently, TUDCA treatment drives broad transcriptional changes correlated with anti-aging characteristics. Mechanistically, we discover that TUDCA targets the chaperone HSP90 to promote its protein refolding activity. This collaboration further alleviates aging-induced endoplasmic reticulum (ER) stress and facilitates protein homeostasis, thus offering resistance to aging. In summary, our findings uncover new molecular links between an endogenous metabolite and protein homeostasis, and propose a novel anti-aging strategy that could improve both lifespan and healthspan.

3.
Small Methods ; : e2400871, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155822

RESUMO

In optical materials, the development of absorbers for a wide spectrum is a focal point of research. A pivotal challenge lies in ensuring the stability and durability of optical absorbers, particularly at elevated temperatures. This study introduces a novel approach to creating absorbers with diverse colors, focusing on the synthesis and properties of black crystal wires. In contrast to black gold nanoparticle (Au NP) precipitates, which change color within hours under similar conditions, the method involves strategically trapping Au NPs within defects during the growth of single crystals. This results in black crystal wires that not only exhibit broadband absorption but also maintain exceptional stability even under prolonged exposure to high temperatures. The method also involves the controlled synthesis of colorless and red crystal wires. As a proof of concept, these stable black Au crystal wires demonstrate superior performance in photothermal conversion applications. The methodology, derived from the crystal growth process, presents a defect template that offers a novel approach to material design. Furthermore, these unique crystals, available in various colors, hold significant promise for a range of unexplored applications.

4.
Nat Commun ; 15(1): 6973, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143058

RESUMO

Mechanochemistry studies the effect of mechanical force on chemical bonds, bringing opportunities for synthesizing alloys, ceramics, organics, polymers, and biomaterials. A vital issue of applying macro-scale mechanical force to manipulate crystal structures is finding ways to precisely adjust the force directions to break micro-scale target chemical bonds. Inspired by a common technique of driving a wedge into the wood to make wood chopping much easier, a wedging strategy of splitting three-dimensional structured crystalline frameworks and then converting them to nanosheets was proposed, where specific molecules were wedged into crystalline frameworks to drive the directional transmission of mechanical force to break chemical bonds. As a result, various crystalline framework nanosheets including metal-organic framework nanosheets, covalent organic framework nanosheets, and coordination polymer nanosheets were fabricated. This wedging crystal strategy exhibits advantages of operability, flexibility and designability, and furthermore, it is expected to expand mechanochemistry applications in material preparation.

5.
Research (Wash D C) ; 7: 0434, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130495

RESUMO

Metal-organic frameworks (MOFs) have been widely considered as ideal platforms for the preparation of biomimetic catalysts, but it remains challenging to fabricate MOF-based enzyme-like catalysts with optimal activity. Here, we leverage the inherent flexibility of MOFs and propose a novel trans-functionalization strategy to construct a carbonic anhydrase (CA) mimic by the structural transformation from ZIF-L to ZIF-8. Theoretical and experimental results reveal that during the structural transformation, the hydroxyl group will preferentially coordinate with the interlayer Zn clusters to form the CA-like active center Zn-N3-OH. Therefore, more accessible active centers are generated on the as-prepared ZIF-8-OH, resulting in substantially enhanced catalytic activity in the hydrolysis of para-nitrophenyl acetate.

6.
Nutrients ; 16(16)2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39203802

RESUMO

Dendritic cells (DCs) are crucial in initiating and shaping both innate and adaptive immune responses. Clinical studies and experimental models have highlighted their significant involvement in various autoimmune diseases, positioning them as promising therapeutic targets. Nicotinamide (NAM), a form of vitamin B3, with its anti-inflammatory properties, has been suggested, while the involvement of NAM in DCs regulation remains elusive. Here, through analyzing publicly available databases, we observe substantial alterations in NAM levels and NAM metabolic pathways during DCs activation. Furthermore, we discover that NAM, but not Nicotinamide Mononucleotide (NMN), significantly inhibits DCs over-activation in vitro and in vivo. The suppression of DCs hyperactivation effectively alleviates symptoms of psoriasis. Mechanistically, NAM impairs DCs activation through a Poly (ADP-ribose) polymerases (PARPs)-NF-κB dependent manner. Notably, phosphoribosyl transferase (NAMPT) and PARPs are significantly upregulated in lipopolysaccharide (LPS)-stimulated DCs and psoriasis patients; elevated NAMPT and PARPs expression in psoriasis patients correlates with higher psoriasis area and severity index (PASI) scores. In summary, our findings underscore the pivotal role of NAM in modulating DCs functions and autoimmune disorders. Targeting the NAMPT-PARP axis emerges as a promising therapeutic approach for DC-related diseases.


Assuntos
Doenças Autoimunes , Células Dendríticas , Niacinamida , Nicotinamida Fosforribosiltransferase , Poli(ADP-Ribose) Polimerases , Psoríase , Transdução de Sinais , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/imunologia , Niacinamida/farmacologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Animais , Psoríase/tratamento farmacológico , Psoríase/imunologia , Psoríase/metabolismo , Doenças Autoimunes/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/metabolismo , Camundongos , Poli(ADP-Ribose) Polimerases/metabolismo , NF-kappa B/metabolismo , Camundongos Endogâmicos C57BL , Lipopolissacarídeos
7.
Nanomaterials (Basel) ; 14(16)2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39195372

RESUMO

The precipitation behavior of Cu-bearing ultra-low carbon steel after step quenching and tempering at 923 K for 0.5-2.5 h was investigated. The size, quantity, and characteristic distribution of nano-precipitates were analyzed using transmission electron microscopy, and the microstructure of B2 (an ordered structure belonging to the body-centered cubic structure), 9R (a special triclinic lattice that has characteristics of rhombohedral structure), 3R (a special triclinic lattice like 9R), and FCT (face-centered tetragonal lattices) were accurately determined. The relationship between nano-precipitates and mechanical properties under different heat treatment processes was obtained, revealing that nano-precipitates effectively enhanced the yield strength of Cu-bearing ultra-low carbon steel. There were two forms of crystal structure evolution sequence of precipitation: B2→multi twin 9R→detwined 9R→FCT→FCC and B2→multi-twin 9R→detwinned 9R→3R→FCT→FCC. The morphology of the precipitated particles during the growth process changed from spherical to ellipsoidal and finally to rod-shaped. It was proven that a stable 3R structure existed due to the coexistence of 9R, 3R, and FCT structures in the same precipitate particle.

8.
Front Immunol ; 15: 1424933, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086485

RESUMO

Introduction: Immunotherapies targeting T cells in solid cancers are revolutionizing clinical treatment. Novel immunotherapies have had extremely limited benefit for acute myeloid leukemia (AML). Here, we characterized the immune microenvironment of t(8;21) AML patients to determine how immune cell infiltration status influenced prognosis. Methods: Through multi-omics studies of primary and longitudinal t(8;21) AML samples, we characterized the heterogeneous immune cell infiltration in the tumor microenvironment and their immune checkpoint gene expression. Further external cohorts were also included in this research. Results: CD8+ T cells were enriched and HAVCR2 and TIGIT were upregulated in the CD34+CD117dim%-High group; these features are known to be associated with immune exhaustion. Data integration analysis of single-cell dynamics revealed that a subset of T cells (cluster_2) (highly expressing GZMB, NKG7, PRF1 and GNLY) evolved and expanded markedly in the drug-resistant stage after relapse. External cohort analysis confirmed that the cluster_2 T-cell signature could be utilized to stratify patients by overall survival outcome. Discussion: In conclusion, we discovered a distinct T-cell signature by scRNA-seq that was correlated with disease progression and drug resistance. Our research provides a novel system for classifying patients based on their immune microenvironment.


Assuntos
Cromossomos Humanos Par 8 , Leucemia Mieloide Aguda , Análise de Célula Única , Microambiente Tumoral , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Análise de Célula Única/métodos , Prognóstico , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Cromossomos Humanos Par 8/genética , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Feminino , Translocação Genética , Cromossomos Humanos Par 21/genética , Linfócitos T CD8-Positivos/imunologia , Adulto , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética
9.
Opt Lett ; 49(15): 4429-4432, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090951

RESUMO

Interferenceless-coded aperture correlation holography (I-COACH) is a promising single-shot 3D imaging method in which a coded phase mask (CPM) is used to encode 3D information about an object into an intensity distribution. However, conventional CPM encoding methods usually lead to intensity dilution, especially in the recording of point spread holograms (PSHs), resulting in low-resolution reconstruction of I-COACH. Here, we propose accelerating quad Airy beams with four mainlobes as a point response to enable weak diffraction propagation and a sharp maximum intensity in the transverse direction. Moreover, the four mainlobes exhibit lateral acceleration in 3D space, so the PSHs in different axial positions show a unique and concentrated intensity distribution on the image sensor, thereby realizing a high-resolution reconstruction of I-COACH. Compared with conventional CPM encoding methods, the proposed accelerating quad Airy-beam-encoding method has superior performance in improving the resolution of I-COACH reconstruction even in the presence of external interference.

10.
Nanoscale Adv ; 6(16): 4230-4236, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39114139

RESUMO

Biomaterials are widely used in regenerative medicine to repair full-thickness skin defect wounds. The adipose-derived stromal vascular fraction (SVF) shows pro-regenerative properties, however, the ex vivo biological activity of SVF is suppressed due to the lack of an external scaffold. Tilapia skin, as a sustained and recyclable biomaterial with low immunogenicity, was applied in the preparation of a hydrogel. The mixture of tilapia skin-derived gelatin and methacrylic anhydride as a scaffold facilitated the paracrine function of SVF and exerted a synergistic effect with SVF to promote wound healing. In this study, 30% (w/v) SVF was added to methacrylate-functionalized tilapia skin gelatin and subsequently exposed to UV irradiation to form a three-dimensional nano-scaffolding composite hydrogel (FG-SVF-3). The effects of paracrine growth factors, neovascularization, and collagen production on wound healing were extensively discussed. FG-SVF-3 displayed a pronounced wound healing ability via in vivo wound models. The FG-SVF-3 hydrogel enhanced the biocompatibility and the expression of EGF, bFGF, and VEGF. FG-SVF-3, as a promising wound dressing, exhibited superior ability to accelerate wound healing, skin regeneration, and wound closure.

11.
Explore (NY) ; 20(5): 103031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38986288

RESUMO

Neutropenia, a common side effect of chemotherapy for ovarian cancer, was observed in a 47-year-old female patient undergoing a six-cycle chemotherapy regimen. She experienced recurrent neutropenia and leukopenia but refused granulocyte colony-stimulating factor (G-CSF) due to severe bone pain and high costs. Moxibustion combined with guasha therapy (MGT) was administered each time neutropenia occurred. The treatment involved guasha therapy on the bladder meridian (BL) and the governor vessel (GV), followed by moxibustion at Zhongwan (CV 12), Guanyuan (CV 4), and Shenzhu (GV 12) points over 2-3 days. This approach led to the recovery of neutrophil and leukocyte counts, enabling the patient to complete six chemotherapy cycles without G-CSF. These findings suggest that MGT may enhance neutrophil and leukocyte counts in patients with chemotherapy-induced myelosuppression, presenting a potential alternative for those intolerant to G-CSF. However, further high-quality research is needed to confirm its efficacy.


Assuntos
Moxibustão , Neutropenia , Neoplasias Ovarianas , Humanos , Feminino , Pessoa de Meia-Idade , Neutropenia/terapia , Neutropenia/induzido quimicamente , Neoplasias Ovarianas/tratamento farmacológico , Moxibustão/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Contagem de Leucócitos , Neutrófilos , Terapia Combinada , Recidiva
12.
Artigo em Inglês | MEDLINE | ID: mdl-39052060

RESUMO

Xiatianwu is a traditional Chinese medicine. This study investigates the function of Xiatianwu in treating HCC through database analyses and in vitro experiments. The active ingredients of Xiatianwu were identified from TCMSP and HERB databases and their targets were predicted by Swiss TargetPrediction. The HCC dataset was screened using the GEO database, and the differentially expressed genes between HCC and non-tumor liver tissues were analyzed to identify overlapping targets with Xiatianwu. The intersecting targets underwent enrichment analysis using R software to elucidate the molecular mechanisms of Xiatianwu against HCC. Core targets were identified using the PPI network and MCODE algorithm. Clinical relevance and disease prognosis in HCC were verified using the TCGA database. Meanwhile, binding affinities among components and targets were validated with molecular docking. Finally, the anti-HCC efficacy of the active ingredient was validated in vitro. Our findings revealed that eight active ingredients of Xiatianwu interacted with 11 key targets, providing anti-HCC efficacy. Molecular docking indicated that bicuculline and fumarine exhibited superior binding abilities. Bicuculline, a representative ingredient of Xiatianwu, was chosen for in vitro validation. Results demonstrated that bicuculline, in a dose-dependent manner inhibited HCC cell viability, reduced migration, suppressed the G0/M cell cycle, and decreased core protein expression. Xiatianwu demonstrates significant potential for clinical application in treating HCC. Bicuculline, a key active ingredient of Xiatianwu, exerts anti-HCC effects by inhibiting the cell cycle.

13.
Adv Ophthalmol Pract Res ; 4(3): 128-133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952566

RESUMO

Purpose: Aims to provide an overview of the contemporary epidemiology of malignant orbital tumors by analyzing population-based incidence patterns across various regions worldwide. Methods: In this article, we retrieved orbital malignancy data from the MEDLINE database and analyzed the incidence and prevalence of orbital malignancies worldwide. We performed the literature search by searching on the Mesh terms for malignant orbital tumors ("orbital", "tumor", "lymphoma", "malignant", "cancer", "incidence", and "epidemiology"). All included studies were published between 1993 and 2023 and were written in English. Results: Ocular or ophthalmic lymphoma most frequently occurred in the orbit, with a prevalence ranging from 47% to 54%. The incidence of malignant orbital tumors was increasing in the USA (2.0 per million (1981-1993), Netherlands (0.86 (1981-1985) to 2.49 (2001-2005) per million) and South Korea (0.3-0.8 per million (1999-2016)), respectively. Ophthalmic lymphoma which includes orbit lymphoma was increasing in Canada (0.17-1.47 per million (1992-2010)), Denmark (0.86 per million (1981-1985) to 2.49 per million (2001-2005)), respectively. Conclusions: The predominant primary malignant orbital tumor in adults was lymphoma. Ocular or ophthalmic lymphoma most frequently occured in the orbit. The limited data available suggested an increasing trend in the incidence of malignant orbital tumors in each country included, which were mainly attributed to the increase in lymphoma. Generally, incidence rates were found to increase with advancing age, with no difference between males and females.

14.
Sci China Life Sci ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39037697

RESUMO

The TET family is well known for active DNA demethylation and plays important roles in regulating transcription, the epigenome and development. Nevertheless, previous studies using knockdown (KD) or knockout (KO) models to investigate the function of TET have faced challenges in distinguishing its enzymatic and nonenzymatic roles, as well as compensatory effects among TET family members, which has made the understanding of the enzymatic role of TET not accurate enough. To solve this problem, we successfully generated mice catalytically inactive for specific Tet members (Tetm/m). We observed that, compared with the reported KO mice, mutant mice exhibited distinct developmental defects, including growth retardation, sex imbalance, infertility, and perinatal lethality. Notably, Tetm/m mouse embryonic stem cells (mESCs) were successfully established but entered an impaired developmental program, demonstrating extended pluripotency and defects in ectodermal differentiation caused by abnormal DNA methylation. Intriguingly, Tet3, traditionally considered less critical for mESCs due to its lower expression level, had a significant impact on the global hydroxymethylation, gene expression, and differentiation potential of mESCs. Notably, there were common regulatory regions between Tet1 and Tet3 in pluripotency regulation. In summary, our study provides a more accurate reference for the functional mechanism of Tet hydroxymethylase activity in mouse development and ESC pluripotency regulation.

15.
Drug Dev Res ; 85(5): e22237, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39032059

RESUMO

The global prevalence of RNA virus infections has presented significant challenges to public health in recent years, necessitating the expansion of its alternative therapeutic library. Due to its evolutional conservation, RNA-dependent RNA polymerase (RdRp) has emerged as a potential target for broad-spectrum antiviral nucleoside analogues. However, after over half a century of structural modification, exploring unclaimed chemical space using frequently-used structural substitution methods to design new nucleoside analogues is challenging. In this study, we explore the use of the "ring-opening" strategy to design new base mimics, thereby using these base mimics to design new nucleoside analogues with broad-spectrum antiviral activities. A total of 29 compounds were synthesized. Their activity against viral RdRp was initially screened using an influenza A virus RdRp high-throughput screening model. Then, the antiviral activity of 38a was verified against influenza virus strain A/PR/8/34 (H1N1), demonstrating a 50% inhibitory concentration (IC50) value of 9.95 µM, which was superior to that of ribavirin (the positive control, IC50 = 11.43 µM). Moreover, 38a also has inhibitory activity against coronavirus 229E with an IC50 of 30.82 µM. In addition, compounds 42 and 46f exhibit an 82% inhibition rate against vesicular stomatitis virus at a concentration of 20 µM and hardly induce cytotoxicity in host cells. This work demonstrates the feasibility of designing nucleoside analogues with "ring-opening" bases and suggests the "ring-opening" nucleosides may have greater polarity, and designing prodrugs is an important aspect of optimizing their antiviral activity. Future research should focus on enhancing the conformational restriction of open-loop bases to mimic Watson-Crick base pairing better and improve antiviral activity.


Assuntos
Antivirais , Desenho de Fármacos , Nucleosídeos , RNA Polimerase Dependente de RNA , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Nucleosídeos/química , Nucleosídeos/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Humanos , Animais , Células Madin Darby de Rim Canino , Cães , Relação Estrutura-Atividade
16.
Biomater Adv ; 163: 213967, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39068744

RESUMO

The healing of skin wounds is a continuous and coordinated process, typically accompanied by microbial colonization and growth. This may result in wound infection and subsequent delay in wound healing. Therefore, it is of particular importance to inhibit the growth of microorganisms in the wound environment. In this study, magnesium hydroxide-doped polycaprolactone (PCL/MH) nanofibrous spheres were fabricated by electrospinning and electrospray techniques to investigate their effects on infected wound healing. The prepared PCL/MH nanofibrous spheres had good porous structure and biocompatibility, providing a favorable environment for the delivery and proliferation of adipose stem cells. The incorporation of MH significantly enhanced the antimicrobial properties of the spheres, in particular, the inhibition of the growth of S. aureus and E. coli. We showed that such PCL/MH nanofibrous spheres had good antimicrobial properties and effectively promoted the regeneration of infected wound tissues, which provided a new idea for the clinical treatment of infected wounds.


Assuntos
Escherichia coli , Hidróxido de Magnésio , Nanofibras , Poliésteres , Pele , Staphylococcus aureus , Cicatrização , Cicatrização/efeitos dos fármacos , Nanofibras/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Poliésteres/química , Pele/efeitos dos fármacos , Pele/microbiologia , Pele/lesões , Animais , Hidróxido de Magnésio/química , Hidróxido de Magnésio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Humanos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Alicerces Teciduais/química
17.
EMBO Rep ; 25(8): 3263-3275, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38866979

RESUMO

As a hallmark of senescent cells, the derepression of Long Interspersed Elements 1 (LINE1) transcription results in accumulated LINE1 cDNA, which triggers the secretion of the senescence-associated secretory phenotype (SASP) and paracrine senescence in a cGAS-STING pathway-dependent manner. However, transcription factors that govern senescence-associated LINE1 reactivation remain ill-defined. Here, we predict several transcription factors that bind to human LINE1 elements to regulate their transcription by analyzing the conserved binding motifs in the 5'-untranslated regions (UTR) of the commonly upregulated LINE1 elements in different types of senescent cells. Further analysis reveals that PAX5 directly binds to LINE1 5'-UTR and the binding is enhanced in senescent cells. The enrichment of PAX5 at the 5'-UTR promotes cellular senescence and SASP by activating LINE1. We also demonstrate that the longevity gene SIRT6 suppresses PAX5 transcription by directly binding to the PAX5 promoter, and overexpressing PAX5 abrogates the suppressive effect of SIRT6 on stress-dependent cellular senescence. Our work suggests that PAX5 could serve as a potential target for drug development aiming to suppress LINE1 activation and treat senescence-associated diseases.


Assuntos
Senescência Celular , Elementos Nucleotídeos Longos e Dispersos , Fator de Transcrição PAX5 , Humanos , Regiões 5' não Traduzidas/genética , Regulação da Expressão Gênica , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Retroelementos/genética , Fenótipo Secretor Associado à Senescência/genética
18.
Materials (Basel) ; 17(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38930400

RESUMO

This study reveals the relationship between the Cu precipitates and mechanical properties of a Cu-baring ultra-low carbon steel after two-phase zone quenching and tempering at 923 K for 0.5-2.5 h. The tensile and microstructural properties were investigated as a function of heat treatment time. The contribution of the precipitation-strengthening mechanism to yield strength was calculated. The size, morphology, and distribution of the precipitated particles were observed using TEM. As the heat treatment time increased, the strength gradually decreased and then remained stable, and the elongation gradually increased and then remained stable. Additionally, the contributions of each strengthening mechanism to the yield strength under different heat treatments were 117, 107, 102, and 89 MPa, respectively. The size and quantity of the precipitates increased with the increase in heat treatment time. After tempering for more than 2 h, the precipitates continued to coarsen, but their quantity decreased. The precipitated Cu had a 3R structure with a length of approximately 17.1 nm and a width of approximately 9.7 nm, with no twinning inside. The stacking order was ABC/ABC. The stable Cu precipitation structure was FCC, maintaining a K-S orientation relationship 11¯1FCC Cu //(0 1 1) α, 1¯10FCC Cu//[11¯1] α.

19.
Biomed Opt Express ; 15(5): 2753-2766, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38855654

RESUMO

Monitoring the transition of cell states during induced pluripotent stem cell (iPSC) differentiation is crucial for clinical medicine and basic research. However, both identification category and prediction accuracy need further improvement. Here, we propose a method combining surface-enhanced Raman spectroscopy (SERS) with convolutional neural networks (CNN) to precisely identify and distinguish cell states during stem cell differentiation. First, mitochondria-targeted probes were synthesized by combining AuNRs and mitochondrial localization signal (MLS) peptides to obtain effective and stable SERS spectra signals at various stages of cell differentiation. Then, the SERS spectra served as input datasets, and their distinctive features were learned and distinguished by CNN. As a result, rapid and accurate identification of six different cell states, including the embryoid body (EB) stage, was successfully achieved throughout the stem cell differentiation process with an impressive prediction accuracy of 98.5%. Furthermore, the impact of different spectral feature peaks on the identification results was investigated, which provides a valuable reference for selecting appropriate spectral bands to identify cell states. This is also beneficial for shortening the spectral acquisition region to enhance spectral acquisition speed. These results suggest the potential for SERS-CNN models in quality monitoring of stem cells, advancing the practical applications of stem cells.

20.
Biomed Opt Express ; 15(5): 2926-2936, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38855674

RESUMO

As one of the important organelles in the process of cell differentiation, mitochondria regulate the whole process of differentiation by participating in energy supply and information transmission. Mitochondrial pH value is a key indicator of mitochondrial function. Therefore, real-time monitoring of mitochondrial pH value during cell differentiation is of great significance for understanding cell biochemical processes and exploring differentiation mechanisms. In this study, Surface-enhanced Raman scattering (SERS) technology was used to achieve the real-time monitoring of mitochondrial pH during induced pluripotent stem cells (iPSCs) differentiation into neural progenitor cells (NPCs). The results showed that the variation trend of mitochondrial pH in normal and abnormal differentiated batches was different. The mitochondrial pH value of normal differentiated cells continued to decline from iPSCs to embryoid bodies (EB) day 4, and continued to rise from EB day 4 to the NPCs stage, and the mitochondrial microenvironment of iPSCs to NPCs differentiation became acidic. In contrast, the mitochondrial pH value of abnormally differentiated cells declined continuously during differentiation. This study improves the information on acid-base balance during cell differentiation and may provide a basis for further understanding of the changes and regulatory mechanisms of mitochondrial metabolism during cell differentiation. This also helps to improve more accurate and useful differentiation protocols based on the microenvironment within the mitochondria, improving the efficiency of cell differentiation.

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