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1.
Circ Res ; 133(6): 463-480, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37555328

RESUMEN

BACKGROUND: Cardiac valve disease is observed in 2.5% of the general population and 10% of the elderly people. Effective pharmacological treatments are currently not available, and patients with severe cardiac valve disease require surgery. PROX1 (prospero-related homeobox transcription factor 1) and FOXC2 (Forkhead box C2 transcription factor) are transcription factors that are required for the development of lymphatic and venous valves. We found that PROX1 and FOXC2 are expressed in a subset of valvular endothelial cells (VECs) that are located on the downstream (fibrosa) side of cardiac valves. Whether PROX1 and FOXC2 regulate cardiac valve development and disease is not known. METHODS: We used histology, electron microscopy, and echocardiography to investigate the structure and functioning of heart valves from Prox1ΔVEC mice in which Prox1 was conditionally deleted from VECs. Isolated valve endothelial cells and valve interstitial cells were used to identify the molecular mechanisms in vitro, which were tested in vivo by RNAScope, additional mouse models, and pharmacological approaches. The significance of our findings was tested by evaluation of human samples of mitral valve prolapse and aortic valve insufficiency. RESULTS: Histological analysis revealed that the aortic and mitral valves of Prox1ΔVEC mice become progressively thick and myxomatous. Echocardiography revealed that the aortic valves of Prox1ΔVEC mice are stenotic. FOXC2 was downregulated and PDGF-B (platelet-derived growth factor-B) was upregulated in the VECs of Prox1ΔVEC mice. Conditional knockdown of FOXC2 and conditional overexpression of PDGF-B in VECs recapitulated the phenotype of Prox1ΔVEC mice. PDGF-B was also increased in mice lacking FOXC2 and in human mitral valve prolapse and insufficient aortic valve samples. Pharmacological inhibition of PDGF-B signaling with imatinib partially ameliorated the valve defects of Prox1ΔVEC mice. CONCLUSIONS: PROX1 antagonizes PDGF-B signaling partially via FOXC2 to maintain the extracellular matrix composition and prevent myxomatous degeneration of cardiac valves.


Asunto(s)
Enfermedades de las Válvulas Cardíacas , Prolapso de la Válvula Mitral , Animales , Humanos , Ratones , Células Endoteliales/metabolismo , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/prevención & control , Enfermedades de las Válvulas Cardíacas/metabolismo , Válvula Mitral/metabolismo , Prolapso de la Válvula Mitral/metabolismo , Factores de Transcripción/metabolismo , Proteínas Proto-Oncogénicas c-sis/metabolismo
2.
EMBO Rep ; 24(9): e55494, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37493024

RESUMEN

Human CST (CTC1-STN1-TEN1) is a ssDNA-binding complex that interacts with the replisome to aid in stalled fork rescue. We previously found that CST promotes telomere replication to maintain genomic integrity via G-quadruplex (G4) resolution. However, the detailed mechanism by which CST resolves G4s in vivo and whether additional factors are involved remains unclear. Here, we identify RECQ4 as a novel CST-interacting partner and show that RECQ4 can unwind G4 structures in vitro using a FRET assay. Moreover, G4s accumulate at the telomere after RECQ4 depletion, resulting in telomere dysfunction, including the formation of MTSs, SFEs, and TIFs, suggesting that RECQ4 is crucial for telomere integrity. Furthermore, CST is also required for RECQ4 telomere or chromatin localization in response to G4 stabilizers. RECQ4 is involved in preserving genomic stability by CST and RECQ4 disruption impairs restart of replication forks stalled by G4s. Overall, our findings highlight the essential roles of CST and RECQ4 in resolving G-rich regions, where they collaborate to resolve G4-induced replication deficiencies and maintain genomic homeostasis.


Asunto(s)
Replicación del ADN , G-Cuádruplex , Humanos , Proteínas de Unión a Telómeros/genética , Homeostasis del Telómero , Telómero/metabolismo
3.
Cell Mol Life Sci ; 81(1): 118, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38448737

RESUMEN

Tektins are microtubule inner proteins (MIPs) and localize at the inside lumen of doublet microtubules (DMTs) of cilia/flagella. TEKTIP1, a newly identified protein by cryo-electron microscopy (cryo-EM), is proposed to be localized at the center of the tektin bundle and hypothesized to recruit tektins or stabilize the bundle. However, the physiological role of TEKTIP1 is unknown. In this study, we generated Tektip1-knockout (Tektip1-/-) mice and showed that they were male subfertile primarily due to reduced sperm motility. A high percentage of sperm from Tektip1-/- mice showed moderately disorganized axoneme structures and abnormal flagellar waveforms. TEKTIP1 predominately interacted with TEKT3 among tektins. Loss of TEKTIP1 partially disturbed the organization of tektin bundle by mainly affecting the native status of TEKT3 and its interaction with other tektins. Collectively, our study reveals the physiological role and potential molecular mechanism of TEKTIP1 in axonemal structure and sperm motility, highlights the importance of MIPs in stabilizing DMTs, and suggests a potential relevance of TEKTIP1 deficiency to human asthenospermia. Tektip1-/- mice will be an excellent animal model to study the DMT organization of sperm flagella using cryo-EM in future.


Asunto(s)
Axonema , Proteínas de Microtúbulos , Semen , Humanos , Masculino , Animales , Ratones , Femenino , Microscopía por Crioelectrón , Motilidad Espermática , Espermatozoides , Flagelos
4.
Am J Epidemiol ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38806817

RESUMEN

Adherence to healthy lifestyle is essential for diabetes management in light of the plateaued metabolic control, diversifying causes of death, and continued excess mortality among people with diabetes (PWD). This study aims to assess the secular trend of adherence to healthy behaviors among PWD in NHANES, a nationally representative survey of Americans using a stratified, multistage probability design in 2-year cycles since 1999. Adherence to healthy lifestyle was estimated using never smoking, moderate drinking, adequate physical activity, and healthy diet, and the score ranged 0-4. Among 7410 participants, adherence to healthy behaviors across time slightly increased from 1.4 (95% CI, 1.3 to 1.5) in 1999-2002 to 1.6 (1.5 to 1.8) in 2015-2018 (Ptrend = 0.002). The non-Hispanic Blacks caught up with the non-Hispanic Whites in overall lifestyle score (1.7 vs. 1.6 in 2015-2018), while large socioeconomic disparities remained in that participants with higher income and education level, and covered by health insurance were more likely to have adherence to healthy behaviors. As the metabolic control plateaued and causes of death have diversified among PWD, our findings suggested a great potential of lifestyle modification in facilitating the long-term health of these patients.

5.
Acc Chem Res ; 56(9): 1087-1096, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37078584

RESUMEN

ConspectusMetal chalcogenide quantum dots (QDs) are prized for their unique and functional properties, associated with both intrinsic (quantum confinement) and extrinsic (high surface area) effects, as dictated by their size, shape, and surface characteristics. Thus, they have considerable promise for diverse applications, including energy conversion (thermoelectrics and photovoltaics), photocatalysis, and sensing. QD gels are macroscopic porous structures consisting of interconnected QDs and pore networks in which the pores may be filled with solvent (i.e., wet gels) or air (i.e., aerogels). QD gels are unique because they can be prepared as macroscale objects while fully retaining the size-specific quantum-confined properties of the initial QD building blocks. The extensive porosity of the gels also ensures that each QD in the gel network is accessible to the ambient, leading to high performance in applications that require high surface areas, such as (photo)catalysis and sensing.Metal chalcogenide QD gels are conventionally prepared by chemical approaches. We recently expanded the toolbox for QD gel synthesis by developing electrochemical gelation methods. Relative to conventional chemical oxidation approaches, electrochemical assembly of QDs (1) enables the use of two additional levers for tuning the QD assembly process and gel structure: electrode material and potential, and (2) allows direct gel formation on device substrates to simplify device fabrication and improve reproducibility. We have discovered two distinct electrochemical gelation methods, each of which enables the direct writing of gels on an active electrode surface or the formation of free-standing monoliths. Oxidative electrogelation of QDs leads to assemblies bridged by dichalcogenide (covalent) linkers, whereas metal-mediated electrogelation proceeds via electrodissolution of active metal electrodes to produce free ions that link QDs by binding to pendant carboxylate functionalities on surface ligands (non-covalent linkers). We further demonstrated that the electrogel composition produced from the covalent assembly could be modified by controlled ion exchange to form single-ion decorated bimetallic QD gels, a new category of materials. The QD gels exhibit unprecedented performance for NO2 gas sensing and unique photocatalytic reactivities (e.g., the "cyano dance" isomerization and the reductive ring-opening arylation). The chemistry unveiled during the development of electrochemical gelation pathways for QDs and their post-modification has broad implications for guiding the design of new nanoparticle assembly strategies and QD gel-based gas sensors and catalysts.

6.
Arch Virol ; 169(2): 22, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38193974

RESUMEN

African swine fever (ASF) is an infectious disease caused by ASF virus (ASFV), which is characterized by high infectivity, rapid onset of disease, and a high mortality rate. Outbreaks of ASFV have caused great economic losses to the global pig industry, and there is a need to develop safe and effective vaccines. In this study, two recombinant pseudorabies virus (PRV) strains, rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L, expressing the EP364R and B119L protein, respectively, of ASFV, were constructed by homologous recombination technology. Western blotting and immunofluorescence analysis showed that these foreign proteins were expressed in cells infected with the recombinant strains. The strains showed good genetic stability and proliferative characteristics for 20 passages in BHK-21 cells. Both of these strains were immunogenic in mice, inducing the production of specific antibodies against the expressed ASFV proteins while providing protection against lethal challenge with PRV. Thus, the recombinant strains rGXGG-2016-ΔgI/ΔgE-EP364R and rGXGG-2016-ΔgI/ΔgE-B119L could be used as candidate vaccines for both ASFV and PRV. In addition, our study identifies two potential target genes for the development of safe and efficient ASFV vaccines, provides a reference for the construction of bivalent ASFV and PRV vaccines, and demonstrates the feasibility of developing a live ASFV vector vaccine.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Herpesvirus Suido 1 , Animales , Ratones , Porcinos , Virus de la Fiebre Porcina Africana/genética , Herpesvirus Suido 1/genética , Fiebre Porcina Africana/prevención & control , Vacunas Atenuadas , Inmunidad
7.
Environ Res ; 252(Pt 3): 119009, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38679277

RESUMEN

Fine particulate matter (PM2.5) harms human health and hinders normal human life. Considering the serious complexity and obvious regional characteristics of PM2.5 pollution, it is urgent to fill in the comprehensive overview of regional characteristics and interannual evolution of PM2.5. This review studied the PM2.5 pollution in six typical areas between 2014 and 2022 based on the data published by the Chinese government and nearly 120 relevant literature. We analyzed and compared the characteristics of interannual and quarterly changes of PM2.5 concentration. The Beijing-Tianjin-Hebei region (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) made remarkable progress in improving PM2.5 pollution, while Fenwei Plain (FWP), Sichuan Basin (SCB) and Northeast Plain (NEP) were slightly inferior mainly due to the relatively lower level of economic development. It was found that the annual average PM2.5 concentration change versus year curves in the three areas with better pollution control conditions can be merged into a smooth curve. Importantly, this can be fitted for the accurate evaluation of each area and provide reliable prediction of its future evolution. In addition, we analyzed the factors affecting the PM2.5 in each area and summarize the causes of air pollution in China. They included primary emission, secondary generation, regional transmission, as well as unfavorable air dispersion conditions. We also suggested that the PM2.5 pollution control should target specific industries and periods, and further research need to be carried out on the process of secondary production. The results provided useful assistance such as effect prediction and strategy guidance for PM2.5 pollution control in Chinese backward areas.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Material Particulado , Material Particulado/análisis , China , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Mejoramiento de la Calidad , Tamaño de la Partícula
8.
J Integr Neurosci ; 23(6): 114, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38940083

RESUMEN

Deep brain stimulation (DBS) is a common therapy for managing Parkinson's disease (PD) in clinical practice. However, a complete understanding of its mode of action is still needed. DBS is believed to work primarily through electrical and neurochemical pathways. Furthermore, DBS has other mechanisms of action. This review explores the fundamental concepts and applications of DBS in treating PD, including its mechanisms, clinical implications, and recent research.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/fisiopatología , Humanos , Encéfalo/fisiopatología , Animales
9.
Ren Fail ; 46(2): 2375103, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38973376

RESUMEN

INTRODUCTION: Cardiovascular events resulting from volume overload are a primary cause of mortality in hemodialysis patients. Bioelectrical impedance analysis (BIA) is significantly valuable for assessing the volume status of hemodialysis (HD) patients. In this article, we explore the correlation between the volume index measured by BIA and the cardiac function index assessed by echocardiography (ECG) in HD patients. METHODS: Between April and November 2018, we conducted a cross-sectional study involving randomly selected 126 maintenance HD patients. Comprehensive data on medical history and laboratory test results were collected. Subsequently, we investigated the correlation between volume indices measured by BIA and cardiac function parameters by ECG. RESULTS: We discovered a significant correlation between the volume indices measured by BIA and various parameter of cardiac function. The Left Ventricular Hypertrophy (LVH) group exhibited higher levels of the percentage of Extracellular Water (ECW%) and the percentage of Total Body Water (TBW%) compared to the Non-LVH group. Extracellular Water (ECW) and Third Interstitial Fluid Volume (TSFV) were identified as independent risk factors for Left Ventricular Mass (LVM), and both demonstrated a high predictive value for LVM. ECW% emerged as an independent risk factor for the Left Ventricular Mass Index (LVMI), with a high predictive value for LVMI. CONCLUSION: ECW and TSFV were found to be positively associated with cardiac function parameters in HD patients.


Asunto(s)
Ecocardiografía , Impedancia Eléctrica , Hipertrofia Ventricular Izquierda , Fallo Renal Crónico , Diálisis Renal , Humanos , Diálisis Renal/efectos adversos , Femenino , Masculino , Estudios Transversales , Persona de Mediana Edad , Ecocardiografía/métodos , Anciano , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/fisiopatología , Hipertrofia Ventricular Izquierda/etiología , Fallo Renal Crónico/terapia , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/fisiopatología , Agua Corporal , Adulto
10.
Genes Dev ; 30(12): 1454-69, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27313318

RESUMEN

Lymphatic vasculature regulates fluid homeostasis by returning interstitial fluid to blood circulation. Lymphatic endothelial cells (LECs) are the building blocks of the entire lymphatic vasculature. LECs originate as a homogeneous population of cells predominantly from the embryonic veins and undergo stepwise morphogenesis to become the lymphatic capillaries, collecting vessels or valves. The molecular mechanisms underlying the morphogenesis of the lymphatic vasculature remain to be fully understood. Here we show that canonical Wnt/ß-catenin signaling is necessary for lymphatic vascular morphogenesis. Lymphatic vascular-specific ablation of ß-catenin in mice prevents the formation of lymphatic and lymphovenous valves. Additionally, lymphatic vessel patterning is defective in these mice, with abnormal recruitment of mural cells. We found that oscillatory shear stress (OSS), which promotes lymphatic vessel maturation, triggers Wnt/ß-catenin signaling in LECs. In turn, Wnt/ß-catenin signaling controls the expression of several molecules, including the lymphedema-associated transcription factor FOXC2. Importantly, FOXC2 completely rescues the lymphatic vessel patterning defects in mice lacking ß-catenin. Thus, our work reveals that mechanical stimulation is a critical regulator of lymphatic vascular development via activation of Wnt/ß-catenin signaling and, in turn, FOXC2.


Asunto(s)
Linfangiogénesis/fisiología , Mecanotransducción Celular/fisiología , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismo , Animales , Células Cultivadas , Células Endoteliales/citología , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Regulación del Desarrollo de la Expresión Génica , Silenciador del Gen , Humanos , Vasos Linfáticos/embriología , Ratones , beta Catenina/genética
11.
Nurs Crit Care ; 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639246

RESUMEN

BACKGROUND: Pneumonia has a high incidence in traumatic brain injury (TBI) patients and lacks effective treatments. Early mobilization (EM) may be a potentially effective treatment. AIM: To explore the impact of EM on TBI-related pneumonia in the neurosurgical intensive care unit (NICU). METHOD: This study was a historical control study. 100 TBI patients who received EM intervention were prospectively included as the experimental group (EM cohort), and 250 TBI patients were retrospectively included as the control group. The propensity score matching (PSM) method was employed to balance baseline and minimize potential bias. The relationship between EM and TBI-related pneumonia was investigated by univariate and multivariate logistic regression, then further determined by subgroup analysis. The influence of other variables was excluded by interaction analyses. Finally, the effect of EM on the prognosis of TBI patients was analysed by comparing the Glasgow Coma Scale (GCS) and the hospital stay. RESULTS: After screening, 86 patients were included in the EM cohort and 199 patients were included in the control cohort. There were obvious differences between the two cohorts at baseline, and these differences were eliminated after PSM, when the incidence of pneumonia was significantly lower in the EM cohort than in the control cohort (35.0% vs. 61.9%, p < .001). Multivariate logistic regression showed that EM was an independent risk factor for TBI-related pneumonia and was significantly associated with a decreased incidence of pneumonia. This correlation was present in most subgroups and was not affected by other variables (p for interaction >.05). Patients in the EM cohort had shorter length of ICU stay (6 vs. 7 days, p = .017) and higher GCS at discharge (12 vs. 11, p = .010). CONCLUSION: EM is a safe and effective treatment for TBI patients in NICU, which can reduce the incidence of pneumonia, help to improve prognosis and shorten the length of ICU stay. RELEVANCE TO CLINICAL PRACTICE: Although the utilization rate of EM is low in TBI patients for various reasons, EM is still an effective method to prevent complications. Our study confirms that a scientific and detailed EM strategy can effectively reduce the incidence of pneumonia while ensuring the safety of TBI patients, which is worthy of further research and clinical application.

12.
Beilstein J Org Chem ; 20: 661-671, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38590540

RESUMEN

Herein, we report a visible-light-mediated palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines, affording unsaturated γ- and ε-amino acid derivatives with diverse structures. In this methodology, the diazo compound readily transforms into a hybrid α-ester alkylpalladium radical with the release of dinitrogen. The radical intermediate selectively adds to the double bond of a 1,3-diene or allene, followed by the allylpalladium radical-polar crossover path and selective allylic substitution with the amine substrate, thereby leading to a single unsaturated γ- or ε-amino acid derivative. This approach proceeds under mild and simple reaction conditions and shows high functional group tolerance, especially in the incorporation of various bioactive molecules. The studies on scale-up reactions and diverse derivatizations highlight the practical utility of this multicomponent reaction protocol.

13.
Br J Haematol ; 202(1): 173-183, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36960712

RESUMEN

The pathophysiologic mechanism of sickle cell disease (SCD) involves polymerization of deoxygenated haemoglobin S (HbS), leading to red blood cell (RBC) sickling, decreased RBC deformability, microvascular obstruction, haemolysis, anaemia and downstream clinical complications. Pharmacological increase in the concentration of oxygenated HbS in RBCs has been shown to be a novel approach to inhibit HbS polymerization and reduce RBC sickling and haemolysis. We report that GBT021601, a small molecule that increases HbS-oxygen affinity, inhibits HbS polymerization and prevents RBC sickling in blood from patients with SCD. Moreover, in a murine model of SCD (SS mice), GBT021601 reduces RBC sickling, improves RBC deformability, prolongs RBC half-life and restores haemoglobin levels to the normal range, while improving oxygen delivery and increasing tolerance to severe hypoxia. Notably, oral dosing of GBT021601 in animals results in higher levels of Hb occupancy than voxelotor and suggests the feasibility of once-daily dosing in humans. In summary, GBT021601 improves RBC health and normalizes haemoglobin in SS mice, suggesting that it may be useful for the treatment of SCD. These data are being used as a foundation for clinical research and development of GBT021601.


Asunto(s)
Anemia de Células Falciformes , Hemólisis , Humanos , Animales , Ratones , Modelos Animales de Enfermedad , Oxígeno , Anemia de Células Falciformes/tratamiento farmacológico , Eritrocitos , Hemoglobinas , Hemoglobina Falciforme
14.
Anal Chem ; 95(42): 15585-15594, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37843131

RESUMEN

Determining the grade of glioma is a critical step in choosing patients' treatment plans in clinical practices. The pathological diagnosis of patient's glioma samples requires extensive staining and imaging procedures, which are expensive and time-consuming. Current advanced uniform-width-constriction-channel-based microfluidics have proven to be effective in distinguishing cancer cells from normal tissues, such as breast cancer, ovarian cancer, prostate cancer, etc. However, the uniform-width-constriction channels can result in low yields on glioma cells with irregular morphologies and high heterogeneity. In this research, we presented an innovative cyclic conical constricted (CCC) microfluidic device to better differentiate glioma cells from normal glial cells. Compared with the widely used uniform-width-constriction microchannels, the new CCC configuration forces single cells to deform gradually and obtains the biophysical attributes from each deformation. The human-derived glioma cell lines U-87 and U-251, as well as the human-derived normal glial astrocyte cell line HA-1800 were selected as the proof of concept. The results showed that CCC channels can effectively obtain the biomechanical characteristics of different 12-25 µm glial cell lines. The patient glioma samples with WHO grades II, III, and IV were tested by CCC channels and compared between Elastic Net (ENet) and Lasso analysis. The results demonstrated that CCC channels and the ENet can successfully select critical biomechanical parameters to differentiate the grades of single-glioma cells. This CCC device can be potentially further applied to the extensive family of brain tumors at the single-cell level.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neoplasias Ováricas , Neoplasias de la Próstata , Masculino , Femenino , Humanos , Microfluídica/métodos , Glioma/patología , Neoplasias Encefálicas/patología , Neoplasias de la Próstata/patología
15.
Development ; 147(23)2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-33144395

RESUMEN

RASA1, a negative regulator of Ras-MAPK signaling, is essential for the development and maintenance of lymphatic vessel valves. However, whether RASA1 is required for the development and maintenance of lymphovenous valves (LVV) and venous valves (VV) is unknown. In this study, we show that induced disruption of Rasa1 in mouse embryos did not affect initial specification of LVV or central VV, but did affect their continued development. Similarly, a switch to expression of a catalytically inactive form of RASA1 resulted in impaired LVV and VV development. Blocked development of LVV was associated with accumulation of the basement membrane protein, collagen IV, in LVV-forming endothelial cells (EC), and could be partially or completely rescued by MAPK inhibitors and drugs that promote collagen IV folding. Disruption of Rasa1 in adult mice resulted in venous hypertension and impaired VV function that was associated with loss of EC from VV leaflets. In conclusion, RASA1 functions as a negative regulator of Ras signaling in EC that is necessary for EC export of collagen IV, thus permitting the development of LVV and the development and maintenance of VV.


Asunto(s)
Desarrollo Embrionario/genética , Organogénesis/genética , Válvulas Venosas/crecimiento & desarrollo , Proteína Activadora de GTPasa p120/genética , Animales , Membrana Basal/crecimiento & desarrollo , Membrana Basal/metabolismo , Colágeno Tipo IV/genética , Embrión de Mamíferos , Células Endoteliales/citología , Vasos Linfáticos/metabolismo , Ratones , Válvulas Venosas/metabolismo
16.
Development ; 147(23)2020 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-33060128

RESUMEN

Lymphatic vasculature is an integral part of digestive, immune and circulatory systems. The homeobox transcription factor PROX1 is necessary for the development of lymphatic vessels, lymphatic valves (LVs) and lymphovenous valves (LVVs). We and others previously reported a feedback loop between PROX1 and vascular endothelial growth factor-C (VEGF-C) signaling. PROX1 promotes the expression of the VEGF-C receptor VEGFR3 in lymphatic endothelial cells (LECs). In turn, VEGF-C signaling maintains PROX1 expression in LECs. However, the mechanisms of PROX1/VEGF-C feedback loop remain poorly understood. Whether VEGF-C signaling is necessary for LV and LVV development is also unknown. Here, we report for the first time that VEGF-C signaling is necessary for valve morphogenesis. We have also discovered that the transcriptional co-activators YAP and TAZ are required to maintain PROX1 expression in LVs and LVVs in response to VEGF-C signaling. Deletion of Yap and Taz in the lymphatic vasculature of mouse embryos did not affect the formation of LVs or LVVs, but resulted in the degeneration of these structures. Our results have identified VEGF-C, YAP and TAZ as a crucial molecular pathway in valve development.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de Ciclo Celular/genética , Proteínas de Homeodominio/genética , Linfangiogénesis/genética , Transactivadores/genética , Proteínas Supresoras de Tumor/genética , Factor C de Crecimiento Endotelial Vascular/genética , Animales , Embrión de Mamíferos , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica/genética , Humanos , Vasos Linfáticos/citología , Vasos Linfáticos/metabolismo , Ratones , Morfogénesis/genética , Transducción de Señal/genética , Válvulas Venosas/crecimiento & desarrollo , Válvulas Venosas/metabolismo , Proteínas Señalizadoras YAP
17.
Microcirculation ; 30(2-3): e12787, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36197446

RESUMEN

INTRODUCTION: Lymphatic vessels collect interstitial fluid, immune cells, and digested lipids and return these bodily fluids to blood through two pairs of lymphovenous valves (LVVs). Like other cardiovascular valves LVVs prevent the backflow of blood into the lymphatic vessels. In addition to LVVs, platelets are necessary to prevent the entry of blood into the lymphatic vessels. Platelet thrombi are observed at LVVs suggesting that LVVs and platelets function in synergy to regulate blood/lymphatic separation. OBJECTIVES: The primary objective of this work is to determine whether platelets can regulate blood/lymph separation independently of LVVs. METHODS: The transcription factor GATA2 is necessary for the development of both LVVs and hematopoietic stem cells. Using various endothelial- and hematopoietic cell expressed Cre-lines, we conditionally deleted Gata2. We hypothesized that this strategy would identify the tissue- and time-specific roles of GATA2 and reveal whether platelets and LVVs can independently regulate blood/lymph separation. RESULTS: Lymphatic vasculature-specific deletion of Gata2 results in the absence of LVVs without compromising blood/lymph separation. In contrast, deletion of GATA2 from both lymphatic vasculature and hematopoietic cells results in the absence of LVVs, reduced number of platelets and blood-filled lymphatic vasculature. CONCLUSION: GATA2 promotes blood/lymph separation through platelets. Furthermore, LVVs are the only known sites of interaction between blood and lymphatic vessels. The fact that blood is able to enter the lymphatic vessels of mice lacking LVVs and platelets indicates that under these circumstances the lymphatic and blood vessels are connected at yet to be identified sites.


Asunto(s)
Plaquetas , Vasos Linfáticos , Ratones , Animales , Factor de Transcripción GATA2/genética
18.
Cell Tissue Res ; 393(3): 455-470, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37450039

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual death of dopaminergic neurons. Brain-derived neurotrophic factor (BDNF) and its receptors are widely distributed throughout the central nervous system, which can promote the survival and growth of neurons and protect neurons. This study revealed that BDNF promotes STAT3 phosphorylation and regulates autophagy in neurons. The PD mouse model was established by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Moreover, SH-SY5Y cells were treated with 1-methyl-4-phenyl-pyridinium (MPP+) to establish a PD cell model. The level of BDNF was low in PD model mice and SH-SY5Y cells treated with MPP+. BDNF enhanced the levels of p-TrkB, P-STAT3, PINK1, and DJ-1. BDNF promoted autophagy, inhibited the level of p-α-syn (Ser129) and enhanced cell proliferation. The autophagy inhibitor 3-Methyladenine (3-methyladenine, 3-MA) reversed the protective effects of BDNF on neurons. BiFC assay results showed that there was a direct physical interaction between BDNF and STAT3, and coimmunoprecipitation experiments indicated an interaction between STAT3 and PI3K. The PI3K agonist Recilisib activated the PI3K/AKT/mTOR pathway, promoted autophagy, and alleviated neuronal cell damage. BDNF alleviates PD pathology by promoting STAT3 phosphorylation and regulating neuronal autophagy in SH-SY5Y cells and cultured primary neurons. Finally, BDNF has neuroprotective effects on PD model mice.


Asunto(s)
Neuroblastoma , Fármacos Neuroprotectores , Enfermedad de Parkinson , Animales , Humanos , Ratones , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Autofagia , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones Endogámicos C57BL , Neuroblastoma/patología , Enfermedad de Parkinson/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Factor de Transcripción STAT3/metabolismo
19.
Cancer Cell Int ; 23(1): 269, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950277

RESUMEN

BACKGROUND: The incidence and prevalence of nonalcoholic fatty liver disease related hepatocellular carcinoma (NAFLD-HCC) are rapidly increasing worldwide. This study aimed to identify biomarker genes for prognostic prediction model of NAFLD-HCC hepatectomy by integrating text-mining, clinical follow-up information, transcriptomic data and experimental validation. METHODS: The tumor and adjacent normal liver samples collected from 13 NAFLD-HCC and 12 HBV-HCC patients were sequenced using RNA-Seq. A novel text-mining strategy, explainable gene ontology fingerprint approach, was utilized to screen NAFLD-HCC featured gene sets and cell types, and the results were validated through a series of lab experiments. A risk score calculated by the multivariate Cox regression model using discovered key genes was established and evaluated based on 47 patients' follow-up information. RESULTS: Differentially expressed genes associated with NAFLD-HCC specific tumor microenvironment were screened, of which FABP4 and VWF were featured by previous reports. A risk prediction model consisting of FABP4, VWF, gender and TNM stage were then established based on 47 samples. The model showed that overall survival in the high-risk score group was lower compared with that in the low-risk score group (p = 0.0095). CONCLUSIONS: This study provided the landscape of NAFLD-HCC transcriptome, and elucidated that our model could predict hepatectomy prognosis with high accuracy.

20.
J Org Chem ; 88(17): 12738-12743, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37611263

RESUMEN

Herein, a straightforward synthetic approach for the construction of phenanthridin-6(5H)-one skeletons is disclosed. The developed protocol relies on palladium catalysis, providing controlled access to a range of functionalized phenanthridin-6(5H)-ones in 59-88% yields. Furthermore, plausible reaction pathways are proposed based on mechanistic experiments.

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