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1.
Plant Cell ; 36(5): 1673-1696, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38142229

RESUMEN

Autocrine signaling pathways regulated by RAPID ALKALINIZATION FACTORs (RALFs) control cell wall integrity during pollen tube germination and growth in Arabidopsis (Arabidopsis thaliana). To investigate the role of pollen-specific RALFs in another plant species, we combined gene expression data with phylogenetic and biochemical studies to identify candidate orthologs in maize (Zea mays). We show that Clade IB ZmRALF2/3 mutations, but not Clade III ZmRALF1/5 mutations, cause cell wall instability in the sub-apical region of the growing pollen tube. ZmRALF2/3 are mainly located in the cell wall and are partially able to complement the pollen germination defect of their Arabidopsis orthologs AtRALF4/19. Mutations in ZmRALF2/3 compromise pectin distribution patterns leading to altered cell wall organization and thickness culminating in pollen tube burst. Clade IB, but not Clade III ZmRALFs, strongly interact as ligands with the pollen-specific Catharanthus roseus RLK1-like (CrRLK1L) receptor kinases Z. mays FERONIA-like (ZmFERL) 4/7/9, LORELEI-like glycosylphosphatidylinositol-anchor (LLG) proteins Z. mays LLG 1 and 2 (ZmLLG1/2), and Z. mays pollen extension-like (PEX) cell wall proteins ZmPEX2/4. Notably, ZmFERL4 outcompetes ZmLLG2 and ZmPEX2 outcompetes ZmFERL4 for ZmRALF2 binding. Based on these data, we suggest that Clade IB RALFs act in a dual role as cell wall components and extracellular sensors to regulate cell wall integrity and thickness during pollen tube growth in maize and probably other plants.


Asunto(s)
Pared Celular , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Tubo Polínico , Transducción de Señal , Zea mays , Zea mays/genética , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo , Pared Celular/metabolismo , Tubo Polínico/crecimiento & desarrollo , Tubo Polínico/genética , Tubo Polínico/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Mutación , Filogenia , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Pectinas/metabolismo , Germinación/genética
2.
FASEB J ; 38(1): e23368, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38100644

RESUMEN

The uterine contraction during labor, a process with repetitive hypoxia and high energy consumption, is essential for successful delivery. However, the molecular mechanism of myometrial contraction regulation is unknown. Serpin family E member 1 (SERPINE1), one of the most upregulated genes in laboring myometrium in both transcriptome and proteome, was highlighted in our previous study. Here, we confirmed SERPINE1 is upregulated in myometrium during labor. Blockade of SERPINE1 using small interfering RNA (siRNA) or inhibitor (Tiplaxtinin) under hypoxic conditions in myocytes or myometrium in vitro showed a decrease contractility, which was achieved by regulating ATP production. Chromatin immunoprecipitation (ChIP-seq), Co-immunoprecipitation (Co-IP), and glutathione-S-transferase (GST) pull down explored that the promoter of SERPINE1 is directly activated by hypoxia-inducible factor-1α (HIF-1α) and SERPINE1 interacts with ATP Synthase Peripheral Stalk Subunit F6 (ATP5PF). Together they enhance hypoxia driven myometrial contraction by maintaining ATP production in the key oxidative phosphorylation pathway. The results provide new insight for uterine contraction regulation, and potential novel therapeutic targets for labor management.


Asunto(s)
Trabajo de Parto , Serpinas , Embarazo , Femenino , Humanos , Serpinas/metabolismo , Miometrio/metabolismo , Contracción Uterina , ARN Interferente Pequeño/metabolismo , Hipoxia/metabolismo , Adenosina Trifosfato/metabolismo
3.
Physiol Genomics ; 56(1): 32-47, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37955337

RESUMEN

The microenvironment and cell populations within the myometrium play crucial roles in maintaining uterine structural integrity and protecting the fetus during pregnancy. However, the specific changes occurring at the single-cell level in the human myometrium between nonpregnant (NP) and term pregnant (TP) states remain unexplored. In this study, we used single-cell RNA sequencing (scRNA-Seq) and spatial transcriptomics (ST) to construct a transcriptomic atlas of individual cells in the myometrium of NP and TP women. Integrated analysis of scRNA-Seq and ST data revealed spatially distinct transcriptional characteristics and examined cell-to-cell communication patterns based on ligand-receptor interactions. We identified and categorized 87,845 high-quality individual cells into 12 populations from scRNA-Seq data of 12 human myometrium tissues. Our findings demonstrated alterations in the proportions of five subpopulations of smooth muscle cells in TP. Moreover, an increase in monocytic cells, particularly M2 macrophages, was observed in TP myometrium samples, suggesting their involvement in the anti-inflammatory response. This study provides unprecedented single-cell resolution of the NP and TP myometrium, offering new insights into myometrial remodeling during pregnancy.NEW & NOTEWORTHY Using single-cell RNA sequencing and spatial transcriptomics, the myometrium was examined at the single-cell level during pregnancy. We identified spatially distinct cell populations and observed alterations in smooth muscle cells and increased M2 macrophages in term pregnant women. These findings offer unprecedented insights into myometrial remodeling and the anti-inflammatory response during pregnancy. The study advances our understanding of pregnancy-related myometrial changes.


Asunto(s)
Miometrio , Útero , Embarazo , Femenino , Humanos , Miometrio/fisiología , Miocitos del Músculo Liso , Antiinflamatorios
4.
Anal Chem ; 96(17): 6634-6642, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38622069

RESUMEN

The ability to deploy decentralized laboratories with autonomous and reliable disease diagnosis holds the potential to deliver accessible healthcare services for public safety. While microfluidic technologies provide precise manipulation of small fluid volumes with improved assay performance, their limited automation and versatility confine them to laboratories. Herein, we report the utility of multicolor assay-on-a-chip processed by robotic operation (MACpro), to address this unmet need. The MACpro platform comprises a robot-microfluidic interface and an eye-in-hand module that provides flexible yet stable actions to execute tasks in a programmable manner, such as the precise manipulation of the microfluidic chip along with different paths. Notably, MACpro shows improved detection performance by integrating the microbead-based antibody immobilization with enhanced target recognition and multicolor sensing via Cu2+-catalyzed plasmonic etching of gold nanorods for rapid and sensitive analyte quantification. Using interferon-gamma as an example, we demonstrate that MACpro completes a sample-to-answer immunoassay within 30 min and achieves a 10-fold broader dynamic range and a 10-fold lower detection limit compared to standard enzyme-linked immunosorbent assays (0.66 vs 5.2 pg/mL). MACpro extends the applications beyond traditional laboratories and presents an automated solution to expand diagnostic capacity in diverse settings.


Asunto(s)
Dispositivos Laboratorio en un Chip , Robótica , Humanos , Inmunoensayo/métodos , Interferón gamma/análisis , Técnicas Analíticas Microfluídicas/instrumentación , Oro/química
5.
Anal Chem ; 96(17): 6692-6699, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38632948

RESUMEN

The antibodies in the natural biological world utilize bivalency/multivalency to achieve a higher affinity for antigen capture. However, mimicking this mechanism on the electrochemical sensing interface and enhancing biological affinity through precise spatial arrangement of bivalent aptamer probes still pose a challenge. In this study, we have developed a novel self-assembly layer (SAM) incorporating triblock polyA DNA to enable accurate organization of the aptamer probes on the interface, constructing a "lock-and-key-like" proximity hybridization assay (PHA) biosensor. The polyA fragment acts as an anchoring block with a strong affinity for the gold surface. Importantly, it connects the two DNA probes, facilitating one-to-one spatial proximity and enabling a controllable surface arrangement. By precisely adjusting the length of the polyA fragment, we can tailor the distance between the probes to match the molecular dimensions of the target protein. This design effectively enhances the affinity of the aptamers. Notably, our biosensor demonstrates exceptional specificity and sensitivity in detecting PDGF-BB, as confirmed through successful validation using human serum samples. Overall, our biosensor presents a novel and versatile interface for proximity assays, offering a significantly improved surface arrangement and detection performance.


Asunto(s)
Aptámeros de Nucleótidos , Becaplermina , Técnicas Biosensibles , Hibridación de Ácido Nucleico , Poli A , Técnicas Biosensibles/métodos , Humanos , Aptámeros de Nucleótidos/química , Becaplermina/sangre , Poli A/química , Oro/química , Sondas de ADN/química
6.
Eur Respir J ; 63(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38514095

RESUMEN

INTRODUCTION: Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. The involvement of T-cell subsets remains unclear. METHODS: We enrolled ABPA patients, asthma patients and healthy controls. T-helper type 1 (Th1), 2 (Th2) and 17 (Th17) cells, regulatory T-cells (Treg) and interleukin (IL)-21+CD4+T-cells in total or sorted subsets of peripheral blood mononuclear cells and ABPA bronchoalveolar lavage fluid (BALF) were analysed using flow cytometry. RNA sequencing of subsets of CD4+T-cells was done in exacerbated ABPA patients and healthy controls. Antibodies of T-/B-cell co-cultures in vitro were measured. RESULTS: ABPA patients had increased Th2 cells, similar numbers of Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T-cells were rarely detected in healthy controls, but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T-cells were mainly peripheral T-helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph cells were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T-helper cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B-cells into plasmablasts and significantly enhanced the production of IgE. CONCLUSION: We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.


Asunto(s)
Aspergilosis Broncopulmonar Alérgica , Linfocitos B , Líquido del Lavado Bronquioalveolar , Células Th2 , Humanos , Masculino , Femenino , Aspergilosis Broncopulmonar Alérgica/inmunología , Adulto , Células Th2/inmunología , Persona de Mediana Edad , Estudios de Casos y Controles , Linfocitos B/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/citología , Linfocitos T Reguladores/inmunología , Asma/inmunología , Células Th17/inmunología , Linfocitos T Colaboradores-Inductores/inmunología
7.
J Virol ; 97(12): e0157423, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38014947

RESUMEN

IMPORTANCE: Marek's disease virus (MDV) is a highly infectious and oncogenic virus that can induce severe T cell lymphomas in chickens. MDV encodes more than 100 genes, most of which have unknown functions. This work indicated that the LORF9 gene is necessary for MDV early cytolytic replication in B lymphocytes. In addition, we have found that the LORF9 deletion mutant has a comparative immunological protective effect with CVI988/Rispens vaccine strain against very virulent MDV challenge. This is a significant discovery that LORF9 can be exploited as a possible target for the development of an MDV gene deletion vaccine.


Asunto(s)
Herpesvirus Gallináceo 2 , Vacunas contra la Enfermedad de Marek , Enfermedad de Marek , Enfermedades de las Aves de Corral , Animales , Linfocitos B , Pollos , Eliminación de Gen , Herpesvirus Gallináceo 2/genética , Enfermedad de Marek/prevención & control , Enfermedad de Marek/genética , Vacunas contra la Enfermedad de Marek/genética , Replicación Viral
8.
Opt Express ; 32(4): 5131-5148, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439247

RESUMEN

Multimode fiber (MMF) is extensively studied for its ability to transmit light modes in parallel, potentially minimizing optical fiber size in imaging. However, current research predominantly focuses on grayscale imaging, with limited attention to color studies. Existing colorization methods often involve costly white light lasers or multiple light sources, increasing optical system expenses and space. To achieve wide-field color images with typical monochromatic illumination MMF imaging system, we proposed a data-driven "colorization" approach and a neural network called SpeckleColorNet, merging U-Net and conditional GAN (cGAN) architectures, trained by a combined loss function. This approach, demonstrated on a 2-meter MMF system with single-wavelength illumination and the Peripheral Blood Cell (PBC) dataset, outperforms grayscale imaging and alternative colorization methods in readability, definition, detail, and accuracy. Our method aims to integrate MMF into clinical medicine and industrial monitoring, offering cost-effective high-fidelity color imaging. It serves as a plug-and-play replacement for conventional grayscale algorithms in MMF systems, eliminating the need for additional hardware.

9.
Cardiovasc Diabetol ; 23(1): 265, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026309

RESUMEN

BACKGROUND: The role of lifestyle factors and their relative contributions to the development and mortality of cardio-renal-metabolic multimorbidity (CRMM) remains unclear. METHODS: A study was conducted with 357,554 UK Biobank participants. CRMM was defined as the coexistence of two or three cardio-renal-metabolic diseases (CRMDs), including cardiovascular disease (CVD), type 2 diabetes (T2D) and chronic kidney disease (CKD). The prospective study examined the associations of individual and combined lifestyle scores (diet, alcohol consumption, smoking, physical activity, sedentary behavior, sleep duration and social connection) with longitudinal progression from healthy to first cardio-renal-metabolic disease (FCRMD), then to CRMM, and ultimately to death, using a multistate model. Subsequently, quantile G-computation was employed to assess the relative contribution of each lifestyle factor. RESULTS: During a median follow-up of 13.62 years, lifestyle played crucial role in all transitions from healthy to FCRMD, then to CRMM, and ultimately to death. The hazard ratios (95% CIs) per score increase were 0.91 (0.90, 0.91) and 0.90 (0.89, 0.91) for healthy to FCRMD, and for FCRMD to CRMM, and 0.84 (0.83, 0.86), 0.87 (0.86, 0.89), and 0.90 (0.88, 0.93) for mortality risk from healthy, FCRMD, and CRMM, respectively. Among the seven factors, smoking status contributed to high proportions for the whole disease progression, accounting for 19.88-38.10%. High-risk diet contributed the largest proportion to the risk of transition from FCRMD to CRMM, with 22.53%. Less-frequent social connection contributed the largest proportion to the risk of transition from FCRMD to death, with 28.81%. When we further consider the disease-specific transitions, we find that lifestyle scores had slightly stronger associations with development to T2D than to CVD or CKD. CONCLUSIONS: Our study indicates that a healthy lifestyle may have a protective effect throughout the longitudinal progression of CRMM, informing more effective management and treatment. Smoking status, diet, and social connection played pivotal roles in specific disease transitions.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Progresión de la Enfermedad , Estilo de Vida , Multimorbilidad , Insuficiencia Renal Crónica , Humanos , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Anciano , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/prevención & control , Estudios Longitudinales , Factores de Tiempo , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/mortalidad , Medición de Riesgo , Reino Unido/epidemiología , Adulto , Factores de Riesgo , Pronóstico , Conducta de Reducción del Riesgo , Fumar/epidemiología , Fumar/efectos adversos , Fumar/mortalidad , Ejercicio Físico , Bases de Datos Factuales , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/mortalidad
10.
Analyst ; 149(12): 3425-3432, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38720619

RESUMEN

Antimicrobial resistance poses a serious threat to human health due to the high morbidity and mortality caused by drug-resistant microbial infections. Therefore, the development of rapid, sensitive and selective identification methods is key to improving the survival rate of patients. In this paper, a sandwich-type electrochemical DNA biosensor based on a polyadenine-DNA tetrahedron probe was constructed. The key experimental conditions were optimized, including the length of polyadenine, the concentration of the polyadenine DNA tetrahedron, the concentration of the signal probe and the hybridization time. At the same time, poly-avidin-HRP80 was used to enhance the electrochemical detection signal. Finally, excellent biosensor performance was achieved, and the detection limit for the synthetic DNA target was as low as 1 fM. In addition, we verified the practicability of the system by analyzing E. coli with the MCR-1 plasmid and realized multi-channel detection of the drug resistance genes MCR-1, blaNDM, blaKPC and blaOXA. With the ideal electrochemical interface, the polyA-based biosensor exhibits excellent stability, which provides powerful technical support for the rapid detection of antibiotic-resistant strains in the field.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Escherichia coli , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Límite de Detección , Hibridación de Ácido Nucleico , Humanos , ADN Bacteriano/genética , ADN Bacteriano/análisis
11.
Inorg Chem ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39015016

RESUMEN

Defect engineering of metal-organic frameworks (MOFs) is a versatile approach to tailoring their electronic structures and photocatalytic performance. Herein, Ce-based porphyrin MOFs (CMFs) featuring controlled structural defects were successfully prepared using a simple acid modulation strategy to drive the photocatalytic H2 generation. The [Ce-O] unit serves as the active site via a ligand-to-metal charge transfer process, which has been confirmed by in situ XPS analysis. Abundant exposed coordinatively unsaturated Ce-O centers are beneficial for the adsorption and activation of water molecules, which is an important factor for improving the photocatalytic performance of the synthesized defective MOFs. In addition, optical and electrochemical experiments indicate that CMFs with more oxygen vacancies possess higher charge separation efficiency. As a result, the optimized CMF(Zn)-200 sample afforded high stability and activity in the H2 generation (up to 1603.3 µmol·g-1·h-1 under cocatalyst-free conditions) and tetracycline hydrochloride removal efficiency (97%), which was 8.45 and 97 times higher than that of pure meso-tetra(4-carboxyphenyl)porphine. This study demonstrates that effective structural modulation and defect introduction can improve the activity and stability of PMOF-based photocatalysts.

12.
Bioorg Chem ; 146: 107320, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38569323

RESUMEN

Spleen tyrosine kinase (Syk) plays a crucial role as a target for allergy treatment due to its involvement in immunoreceptor signaling. The purpose of this study was to identify natural inhibitors of Syk and assess their effects on the IgE-mediated allergic response in mast cells and ICR mice. A list of eight compounds was selected based on pharmacophore and molecular docking, showing potential inhibitory effects through virtual screening. Among these compounds, sophoraflavanone G (SFG) was found to inhibit Syk activity in an enzymatic assay, with an IC50 value of 2.2 µM. To investigate the conformational dynamics of the SYK-SFG system, we performed molecular dynamics simulations. The stability of the binding between SFG and Syk was evaluated using root mean square deviation (RMSD) and root mean square fluctuation (RMSF). In RBL-2H3 cells, SFG demonstrated a dose-dependent suppression of IgE/BSA-induced mast cell degranulation, with no significant cytotoxicity observed at concentrations below 10.0 µM within 24 h. Furthermore, SFG reduced the production of TNF-α and IL-4 in RBL-2H3 cells. Mechanistic investigations revealed that SFG inhibited downstream signaling proteins, including phospholipase Cγ1 (PLCγ1), as well as mitogen-activated protein kinases (AKT, Erk1/2, p38, and JNK), in mast cells in a dose-dependent manner. Passive cutaneous anaphylaxis (PCA) experiments demonstrated that SFG could reduce ear swelling, mast cell degranulation, and the expression of COX-2 and IL-4. Overall, our findings identify naturally occurring SFG as a direct inhibitor of Syk that effectively suppresses mast cell degranulation both in vitro and in vivo.


Asunto(s)
Interleucina-4 , Mastocitos , Ratones , Animales , Interleucina-4/metabolismo , Interleucina-4/farmacología , Mastocitos/metabolismo , Anafilaxis Cutánea Pasiva , Simulación del Acoplamiento Molecular , Inmunoglobulina E/metabolismo , Inmunoglobulina E/farmacología , Ratones Endogámicos ICR , Ratones Endogámicos BALB C
13.
Acta Pharmacol Sin ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862817

RESUMEN

Suppression of neuroinflammation using small molecule compounds targeting the key pathways in microglial inflammation has attracted great interest. Recently, increasing attention has been gained to the role of the second bromodomain (BD2) of the bromodomain and extra-terminal (BET) proteins, while its effect and molecular mechanism on microglial inflammation has not yet been explored. In this study, we evaluated the therapeutic effects of ABBV-744, a BD2 high selective BET inhibitor, on lipopolysaccharide (LPS)-induced microglial inflammation in vitro and in vivo, and explored the key pathways by which ABBV-744 regulated microglia-mediated neuroinflammation. We found that pretreatment of ABBV-744 concentration-dependently inhibited the expression of LPS-induced inflammatory mediators/enzymes including NO, TNF-α, IL-1ß, IL-6, iNOS, and COX-2 in BV-2 microglial cells. These effects were validated in LPS-treated primary microglial cells. Furthermore, we observed that administration of ABBV-744 significantly alleviated LPS-induced activation of microglia and transcriptional levels of pro-inflammatory factors TNF-α and IL-1ß in mouse hippocampus and cortex. RNA-Sequencing (RNA-seq) analysis revealed that ABBV-744 induced 508 differentially expressed genes (DEGs) in LPS-stimulated BV-2 cells, and gene enrichment and gene expression network analysis verified its regulation on activated microglial genes and inflammatory pathways. We demonstrated that pretreatment of ABBV-744 significantly reduced the expression levels of basic leucine zipper ATF-like transcription factor 2 (BATF2) and interferon regulatory factor 4 (IRF4), and suppressed JAK-STAT signaling pathway in LPS-stimulated BV-2 cells and mice, suggesting that the anti-neuroinflammatory effect of ABBV-744 might be associated with regulation of BATF2-IRF4-STAT1/3/5 pathway, which was confirmed by gene knockdown experiments. This study demonstrates the effect of a BD2 high selective BET inhibitor, ABBV-744, against microglial inflammation, and reveals a BATF2-IRF4-STAT1/3/5 pathway in regulation of microglial inflammation, which might provide new clues for discovery of effective therapeutic strategy against neuroinflammation.

14.
Planta Med ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38838717

RESUMEN

Thrombin is a crucial enzyme in the coagulation cascade, and inhibitors of thrombin have been extensively studied as potential antithrombotic agents. The objective of this study was to identify natural inhibitors of thrombin from Panax notoginseng and evaluate their biological activity in vitro and binding characteristics. A combined approach involving molecular docking, thrombin inhibition assays, surface plasmon resonance, and molecular dynamics simulation was utilized to identify natural thrombin inhibitors. The results demonstrated that panaxatriol directly inhibits thrombin, with an IC50 of 10.3 µM. Binding studies using surface plasmon resonance revealed that panaxatriol interacts with thrombin, with a KD value of 7.8 µM. Molecular dynamics analysis indicated that the thrombin-panaxatriol system reached equilibrium rapidly with minimal fluctuations, and the calculated binding free energy was - 23.8 kcal/mol. The interaction between panaxatriol and thrombin involves the amino acid residues Glu146, Glu192, Gly216, Gly219, Tyr60A, and Trp60D. This interaction provides a mechanistic basis for further optimizing panaxatriol as a thrombin inhibitor. Our study has shown that panaxatriol serves as a direct thrombin inhibitor, laying the groundwork for further research and development of novel thrombin inhibitors.

15.
Int J Mol Sci ; 25(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38791462

RESUMEN

Small interfering RNA (siRNA) has significant potential as a treatment for cancer by targeting specific genes or molecular pathways involved in cancer development and progression. The addition of siRNA to other therapeutic strategies, like photodynamic therapy (PDT), can enhance the anticancer effects, providing synergistic benefits. Nevertheless, the effective delivery of siRNA into target cells remains an obstacle in cancer therapy. Herein, supramolecular nanoparticles were fabricated via the co-assembly of natural histone and hyaluronic acid for the co-delivery of HMGB1-siRNA and the photosensitizer chlorin e6 (Ce6) into the MCF-7 cell. The produced siRNA-Ce6 nanoparticles (siRNA-Ce6 NPs) have a spherical morphology and exhibit uniform distribution. In vitro experiments demonstrate that the siRNA-Ce6 NPs display good biocompatibility, enhanced cellular uptake, and improved cytotoxicity. These outcomes indicate that the nanoparticles constructed by the co-assembly of histone and hyaluronic acid hold enormous promise as a means of siRNA and photosensitizer co-delivery towards synergetic therapy.


Asunto(s)
Histonas , Ácido Hialurónico , Nanopartículas , Fármacos Fotosensibilizantes , ARN Interferente Pequeño , Ácido Hialurónico/química , Humanos , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/química , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/administración & dosificación , Nanopartículas/química , Histonas/metabolismo , Células MCF-7 , Fotoquimioterapia/métodos , Porfirinas/química , Porfirinas/farmacología , Clorofilidas , Supervivencia Celular/efectos de los fármacos
16.
Molecules ; 29(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38792165

RESUMEN

The objective of this study was to identify multiple alkaloids in Coptis chinensis that demonstrate inhibitory activity against DPP-4 and systematically evaluate their activity and binding characteristics. A combined strategy that included molecular docking, a DPP-4 inhibition assay, surface plasmon resonance (SPR), and a molecular dynamics simulation technique was employed. The results showed that nine alkaloids in Coptis chinensis directly inhibited DPP-4, with IC50 values of 3.44-53.73 µM. SPR-based binding studies revealed that these alkaloids display rapid binding and dissociation characteristics when interacting with DPP-4, with KD values ranging from 8.11 to 29.97 µM. A molecular dynamics analysis revealed that equilibrium was rapidly reached by nine DPP-4-ligand systems with minimal fluctuations, while binding free energy calculations showed that the ∆Gbind values for the nine test compounds ranged from -31.84 to -16.06 kcal/mol. The most important forces for the binding of these alkaloids with DPP-4 are electrostatic interactions and van der Waals forces. Various important amino acid residues, such as Arg125, His126, Phe357, Arg358, and Tyr547, were involved in the inhibition of DPP-4 by the compounds, revealing a mechanistic basis for the further optimization of these alkaloids as DPP-4 inhibitors. This study confirmed nine alkaloids as direct inhibitors of DPP-4 and characterized their binding features, thereby providing a basis for further research and development on novel DPP-4 inhibitors.


Asunto(s)
Alcaloides , Coptis , Dipeptidil Peptidasa 4 , Inhibidores de la Dipeptidil-Peptidasa IV , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de la Dipeptidil-Peptidasa IV/química , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Coptis/química , Dipeptidil Peptidasa 4/química , Dipeptidil Peptidasa 4/metabolismo , Alcaloides/química , Alcaloides/farmacología , Unión Proteica , Humanos , Sitios de Unión , Resonancia por Plasmón de Superficie , Descubrimiento de Drogas/métodos
17.
Anal Chem ; 95(23): 8816-8824, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37194113

RESUMEN

The development of electrochemical DNA biosensors has been limited by their reliability and reproducibility due to many interfering factors such as electrode properties, DNA surface densities, and complex biological samples. In this work, we developed a nanobalance polyA hairpin probe (polyA-HP), which was effectively assembled onto the gold electrode surface through the affinity between the central polyA fragment and the Au surface. One flanking probe of the polyA-HP captured the target sequence together with a MB-labeled signal probe, and the other flanking probe captured a reference probe simultaneously. The MB signal related to the amount of target was normalized by the reference Fc signal; thus, the signal-to-noise (S/N) was as high as 2000, and the reproducibility was remarkably improved to 2.77%, even facing deliberately changed experiment conditions. By designing a hairpin structure at the terminal of the polyA-HP, the selectivity and specificity were dramatically improved for the analysis of mismatched sequences. The analysis performance of biological samples was dramatically improved after normalization, which is critical for its practicability. Our novel biosensor is a universal single-molecule platform for ratiometric biosensors with excellent performance in real samples, indicating great potential for next-generation high-precision electrochemical sensors.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Reproducibilidad de los Resultados , ADN/análisis , Oro/química , Límite de Detección
18.
Biol Chem ; 404(11-12): 1069-1084, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37674329

RESUMEN

mRNA translation is tightly regulated by various classes of RNA-binding proteins (RBPs) during development and in response to changing environmental conditions. In this study, we characterize the arginine-glycine-glycine (RGG) motif containing RBP family of Arabidopsis thaliana representing homologues of the multifunctional translation regulators and ribosomal preservation factors Stm1 from yeast (ScStm1) and human SERBP1 (HsSERBP1). The Arabidopsis genome encodes three RGG proteins named AtRGGA, AtRGGB and AtRGGC. While AtRGGA is ubiquitously expressed, AtRGGB and AtRGGC are enriched in dividing cells. All AtRGGs localize almost exclusively to the cytoplasm and bind with high affinity to ssRNA, while being capable to interact with most nucleic acids, except dsRNA. A protein-interactome study shows that AtRGGs interact with ribosomal proteins and proteins involved in RNA processing and transport. In contrast to ScStm1, AtRGGs are enriched in ribosome-free fractions in polysome profiles, suggesting additional plant-specific functions. Mutant studies show that AtRGG proteins differentially regulate flowering time, with a distinct and complex temperature dependency for each AtRGG protein. In conclusion, we suggest that AtRGGs function in fine-tuning translation efficiency to control flowering time and potentially other developmental processes in response to environmental changes.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Temperatura , Proteínas de Unión al ARN/química , Citosol/metabolismo , Glicina/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo
19.
Opt Express ; 31(23): 37408-37425, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-38017870

RESUMEN

In this article, a thorough model of linearly polarized fiber laser considering polarization coupling, mode coupling, SBS, and SRS effects is established. The output results of direct pumping and tandem pumping linearly polarized fiber laser under different SBS and SRS intensity settings are simulated. The results show that direct pumping is a better pumping scheme at present, and if the doping concentration of gain fiber can be further increased and the mode field quality of corresponding passive fiber can be optimized, the disadvantages of tandem pumping can be suppressed. To explore the potential of tandem pumping, a backward tandem pumped linearly polarized fiber amplifier is built and 875 W over 13 dB linearly polarized laser output is obtained.

20.
Opt Lett ; 48(7): 1794-1797, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221768

RESUMEN

By amplifying the cascaded random Raman fiber laser (RRFL) oscillator and ytterbium fiber laser oscillator, we present the first, to the best of our knowledge, demonstration of a 10-kW-level high-spectral-purity all-fiber ytterbium-Raman fiber amplifier (Yb-RFA). With a carefully designed backward-pumped RRFL oscillator structure, the parasitic oscillation between the cascaded seeds is avoided. Leveraging the RRFL with full-open-cavity as the Raman seed, the Yb-RFA realizes 10.7-kW Raman lasing at 1125 nm, which is beyond the operating wavelengths of all the reflection components used in the system. The spectral purity of the Raman lasing reaches 94.7% and the 3-dB bandwidth is 3.9 nm. This work paves a way to combine the temporal stability of the RRFL seed and the power scaling of Yb-RFA, enabling the wavelength extension of high-power fiber lasers with high spectral purity.

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