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Toxoplasma gondii infection in pregnant women may cause fetal anomalies; however, the underlying mechanisms remain unclear. The current study investigated whether T. gondii induces pyroptosis in human placental cells and the underlying mechanisms. Human placental trophoblast (BeWo and HTR-8/SVneo) and amniotic (WISH) cells were infected with T. gondii, and then reactive oxygen species (ROS) production, cathepsin B (CatB) release, inflammasome activation, and pyroptosis induction were evaluated. The molecular mechanisms of these effects were investigated by treating the cells with ROS scavengers, a CatB inhibitor, or inflammasome-specific siRNA. T. gondii infection induced ROS generation and CatB release into the cytosol in placental cells but decreased mitochondrial membrane potential. T. gondii-infected human placental cells and villi exhibited NLRP1, NLRP3, NLRC4, and AIM2 inflammasome activation and subsequent pyroptosis induction, as evidenced by increased expression of ASC, cleaved caspase-1, and mature IL-1ß and gasdermin D cleavage. In addition to inflammasome activation and pyroptosis induction, adverse pregnancy outcome was shown in a T. gondii-infected pregnant mouse model. Administration of ROS scavengers, CatB inhibitor, or inflammasome-specific siRNA into T. gondii-infected cells reversed these effects. Collectively, these findings show that T. gondii induces NLRP1/NLRP3/NLRC4/AIM2 inflammasome-dependent caspase-1-mediated pyroptosis via induction of ROS production and CatB activation in placental cells. This mechanism may play an important role in inducing cell injury in congenital toxoplasmosis.
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Inflamasomas , Toxoplasma , Ratones , Animales , Humanos , Femenino , Embarazo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Piroptosis , Trofoblastos/metabolismo , Catepsina B/metabolismo , Catepsina B/farmacología , Placenta/metabolismo , ARN Interferente Pequeño , Caspasas/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas Adaptadoras de Señalización CARD/metabolismo , Proteínas NLR/metabolismoRESUMEN
Herein, three In(III)-based metal-organic frameworks (In-MOFs) with different degrees of interpenetration (DOI), namely In-MOF-1, In-MOF-2, and In-MOF-3, constructed by In3+ and Y-shaped ligands 4,4',4â³-s-triazine-2,4,6-triyltribenzoate (H3TATB), are successfully synthesized through the ionothermal/solvothermal method. Subsequently, three novel In-MOFs, including noninterpenetration polycatenation, 2-fold interpenetrated, and 4-fold interpenetrated structure, are employed as the platform for systematically investigating the separation efficiency of CO2/N2, CO2/CH4, and CO2/CH4/N2 mixture gas system. Among them, In-MOF-2 shows the highest CO2 uptake capacities at 298 K and simultaneously possesses the low adsorption enthalpy of CO2 (26.4 kJ/mol at low coverage), a feature desirable for low-energy-cost adsorbent regeneration. The CO2/N2 (v: v = 15/85) selectivity of In-MOF-2 reaches 37.6 (at 298 K and 1 bar), also revealing outstanding selective separation ability from flue gases and purifying natural gas, affording a unique robust separation material as it has moderate DOI and pore size. In-MOF-2 shows exceptional stability and feasibility to achieve reproducibility. Aperture adjustment makes In-MOF-2 a versatile platform for selectively capturing CO2 from flue gases or purifying natural gas.
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Oily water caused in the process of industry leads to not only the waste of resources, but also environmental pollution. Membrane separation, as a facile and efficient separation technology, has attracted widespread attention in the field of oil/water separation. The development of membrane materials with high separation performance is one of the key elements to improve separation efficiency. In this work, a superhydrophobic membrane composited with a trifluoromethyl-containing covalent organic framework (COF) is prepared, which exhibits excellent performance on separations of oil/water mixtures and water-in-oil emulsions. For different composition of oil/water mixtures, the highest flux of oil is up to 32 000 L m-2 h-1 and oil/water separation efficiency is above 99%. Moreover, the high oil/water separation efficiency remains unchanged after successive cycles. This work provides a feasible scheme for the design of high-efficiency oil/water separation membranes.
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Estructuras Metalorgánicas , Membranas , Contaminación Ambiental , Tecnología , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
The immune system is a complicated, closely regulated mechanism that evolved to keep people healthy from infectious pathogens. Phagocytosis is important for both innate and acquired immunity, which is a critical process for microbial pathogens and apoptotic cells to be consumed and eliminated. However, several pathogens have evolved different strategies to escape detection and killing by phagocytosis. Recently, with the increase in infectious diseases and antibiotic resistance, it is significant for people to have a deep understanding of immune evasion, which may become an opportunity to explore new treatments and vaccination. Additionally, researchers mostly study immune evasion of a single pathogen but rarely summarize pathogens from the perspective of immune mechanisms. Here, we present the current understanding of phagocytosis and give a brief discussion of how pathogens control phagocytosis at different stages.
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Enfermedades Transmisibles , Fagocitosis , Humanos , Evasión InmuneRESUMEN
Toxoplasma gondii, an intracellular protozoan parasite that infects one-third of the world's population, has been reported to hijack host cell apoptotic machinery and promote either an anti- or proapoptotic program depending on the parasite virulence and load and the host cell type. However, little is known about the regulation of human FHs 74 small intestinal epithelial cell viability in response to T. gondii infection. Here we show that T. gondii RH strain tachyzoite infection or ESP treatment of FHs 74 Int cells induced apoptosis, mitochondrial dysfunction and ER stress in host cells. Pretreatment with 4-PBA inhibited the expression or activation of key molecules involved in ER stress. In addition, both T. gondii and ESP challenge-induced mitochondrial dysfunction and cell death were dramatically suppressed in 4-PBA pretreated cells. Our study indicates that T. gondii infection induced ER stress in FHs 74 Int cells, which induced mitochondrial dysfunction followed by apoptosis. This may constitute a potential molecular mechanism responsible for the foodborne parasitic disease caused by T. gondii.
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Toxoplasma , Apoptosis , Estrés del Retículo Endoplásmico , Células Epiteliales , Humanos , MitocondriasRESUMEN
An ultranarrow-bandwidth-optical-receiver-based ultraviolet trifrequency Rayleigh Doppler wind lidar (DWL) technology is proposed that is able to simultaneously detect stratospheric wind with high precision during the daytime. The lidar system is designed, and the principle of wind measurement is analyzed. An ultranarrow-bandwidth element used for suppressing strong background light is designed as an important part of the ultranarrow-bandwidth optical receiver. A three-channel Fabry-Perot interferometer (FPI) is capable of measuring wind speed. A non-polarized beam splitter cube optically contacted on the three-channel FPI can offer a stable splitting ratio. The parameters of the three-channel FPI are optimized. The structure and parameters of the ultranarrow-bandwidth element are designed, and the transmission curve is measured. The transmission curve and stability of the three-channel FPI are validated. The background photon number is collected with the ultranarrow-bandwidth element and with an interference filter (IF) alternately from 08:00 to 18:00. Based on the selected system parameters and measured background photon number, the detection performance of the proposed lidar is simulated. Simulation results show that with 200 m range resolution from 15 to 25 km, 500 m range resolution from 25 to 40 km, and 30 min total accumulation time for paired line-of-sight (LOS) measurement, within $\pm {100}\;{\rm m/s}$±100m/s LOS wind speed range, the daytime LOS wind speed error is below 4.77 m/s from 15 to 40 km altitude. Compared with the traditional IF-based dual-FPI Rayleigh Doppler lidar, the wind speed accuracies are improved by 1.29-16.29 times and the detection altitudes are improved from 23.55 to 40 km with the same wind-detecting precision.
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Toxoplasma gondii is an intracellular parasite that causes severe disease when the infection occurs during pregnancy. Adenosine is a purine nucleoside involved in numerous physiological processes; however, the role of adenosine receptors in T. gondii-induced trophoblast cell function has not been investigated until now. The goal of the present study was to evaluate the intracellular signaling pathways regulated by adenosine receptors using a HTR-8/SVneo trophoblast cell model of T. gondii infection. HTR8/SVneo human extravillous trophoblast cells were infected with or without T. gondii and then evaluated for cell morphology, intracellular proliferation of the parasite, adenosine receptor expression, TNF-α production and mitogen-activated protein (MAP) kinase signaling pathways triggered by adenosine A3 receptor (A3AR). HTR8/SVneo cells infected with T. gondii exhibited an altered cytoskeletal changes, an increased infection rate and reduced viability in an infection time-dependent manner. T. gondii significantly promoted increased TNF-α production, A3AR protein levels and p38, ERK1/2 and JNK phosphorylation compared to those observed in uninfected control cells. Moreover, the inhibition of A3AR by A3AR siRNA transfection apparently suppressed the T. gondii infection-mediated upregulation of TNF-α, A3AR production and MAPK activation. In addition, T. gondii-promoted TNF-α secretion was dramatically attenuated by pretreatment with PD098059 or SP600125. These results indicate that A3AR-mediated activation of ERK1/2 and JNK positively regulates TNF-α secretion in T. gondii-infected HTR8/SVneo cells.
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MAP Quinasa Quinasa 4/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Receptor de Adenosina A3/fisiología , Toxoplasmosis/metabolismo , Trofoblastos/metabolismo , Trofoblastos/parasitología , Factor de Necrosis Tumoral alfa/metabolismo , Células Cultivadas , HumanosRESUMEN
Long-term exposure to overloaded mechanical environment induces bone fatigue damage symptoms and osteoblast damages. Montelukast is a selective cysteinyl leukot-riene receptor 1 (cysLT1R) antagonist, which has been used for the treatment of bronchial asthma in clinics. In the current study, we have identified a novel pharmacological role of montelukast by finding that it has protective properties against overload damage in osteoblastic MC3T3-E1 cells. Firstly, our results show that CysLT1R is expressed in MC3T3-E1 cells. Mechanical tensile strain of 5000-7000 µÎµ resulted in a significant upregulation of CysLT1R in osteoblastic MC3T3-E1 cells in an intensity dependent manner. Secondly, MTT assay indicates that loading with 5000 µÎµ mechanical strain inhibited cell proliferation, which was suppressed by montelukast treatment. Furthermore, montelukast promotes cell differentiation by increasing the expression of ALP and RUNX2. Alizarin Red S staining assay showed that montelukast abolished the inhibitory effects of overload mechanics on osteoblast mineralization. Mechanistically, the effect of montelukast on osteoblastic differentiation acted by activating the extracellular regulated protein kinases (ERK) pathway. The obtained results suggested that montelukast promotes proliferation and differentiation in osteoblasts exposed to overload mechanics.
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Acetatos/administración & dosificación , Diferenciación Celular/fisiología , Antagonistas de Leucotrieno/administración & dosificación , Mecanotransducción Celular/fisiología , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Quinolinas/administración & dosificación , Receptores de Leucotrienos/metabolismo , Células 3T3 , Animales , Ciclopropanos , Regulación del Desarrollo de la Expresión Génica/fisiología , Ratones , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteogénesis/fisiología , Receptores de Leucotrienos/efectos de los fármacos , Estrés Mecánico , SulfurosRESUMEN
There are seven antigenically distinct serotypes of foot-and-mouth disease virus (FMDV), each of which has intratypic variants. In the present study, we have developed methods to efficiently generate promising vaccines against seven serotypes or subtypes. The capsid-encoding gene (P1) of the vaccine strain O1/Manisa/Turkey/69 was replaced with the amplified or synthetic genes from the O, A, Asia1, C, SAT1, SAT2, and SAT3 serotypes. Viruses of the seven serotype were rescued successfully. Each chimeric FMDV with a replacement of P1 showed serotype-specific antigenicity and varied in terms of pathogenesis in pigs and mice. Vaccination of pigs with an experimental trivalent vaccine containing the inactivated recombinants based on the main serotypes O, A, and Asia1 effectively protected them from virus challenge. This technology could be a potential strategy for a customized vaccine with challenge tools to protect against epizootic disease caused by specific serotypes or subtypes of FMDV.IMPORTANCE Foot-and-mouth disease (FMD) virus (FMDV) causes significant economic losses. For vaccine preparation, the selection of vaccine strains was complicated by high antigenic variation. In the present study, we suggested an effective strategy to rapidly prepare and evaluate mass-produced customized vaccines against epidemic strains. The P1 gene encoding the structural proteins of the well-known vaccine virus was replaced by the synthetic or amplified genes of viruses of seven representative serotypes. These chimeric viruses generally replicated readily in cell culture and had a particle size similar to that of the original vaccine strain. Their antigenicity mirrored that of the original serotype from which their P1 gene was derived. Animal infection experiments revealed that the recombinants varied in terms of pathogenicity. This strategy will be a useful tool for rapidly generating customized FMD vaccines or challenge viruses for all serotypes, especially for FMD-free countries, which have prohibited the import of FMDVs.
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Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Vacunas Virales/inmunología , Animales , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Modelos Animales de Enfermedad , Fiebre Aftosa/inmunología , Fiebre Aftosa/patología , Virus de la Fiebre Aftosa/genética , Virus de la Fiebre Aftosa/patogenicidad , Ratones , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Porcinos , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/aislamiento & purificación , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/aislamiento & purificación , Vacunas Virales/administración & dosificación , Vacunas Virales/aislamiento & purificaciónRESUMEN
Atg4 is essential for autophagosome formation and Atg8 recycle with the function of processing the precursor and the lipidated Atg8-family proteins. Abnormal autophagic activity is involved in a variety of pathophysiological diseases and ATG4B is of interest as a potential therapeutic target due to its key roles in autophagy process. So ATG4B inhibitors are highly needed. FMK-9a is the most potent inhibitor reported so far. In this study, we confirmed FMK-9a could suppress ATG4B activity in vitro and in cells, with an IC50 of 260 nM. Besides, FMK-9a could also attenuate the process of cleavage of pro-LC3 and the delipidation of LC3-PE. Importantly, FMK-9a could induce autophagy both in HeLa and MEF cells regardless of its inhibition on ATG4B activity. Moreover, FMK-9a induced autophagy required FIP200 and ATG5. In conclusion, we demonstrated that ATG4B inhibitor FMK-9a induces autophagy independent on its enzyme inhibition. Thus, FMK-9a may plays multiple roles in autophagy process and cannot simply take it as an ATG4B inhibitor.
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Proteínas Relacionadas con la Autofagia , Autofagia/efectos de los fármacos , Cisteína Endopeptidasas , Inhibidores de Cisteína Proteinasa/farmacología , Animales , Proteínas Relacionadas con la Autofagia/antagonistas & inhibidores , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Células HeLa , Humanos , Lipoilación/efectos de los fármacos , Ratones , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismoRESUMEN
Toxoplasma gondii is an apicomplexan zoonotic protozoan parasite that infects most species of warm-blooded animals, including humans. The heavy incidence and severe or lethal damage caused by T. gondii infection clearly indicate a need for the development of an effective vaccine. T. gondii GRA8 is a member of the dense granules protein family and is used as a marker of acute infection. In the present study, we evaluated the protective immunity induced by DNA vaccination based on a recombinant eukaryotic plasmid, pDsRed2-GRA8, against acute toxoplasmosis in mice. BALB/c mice were intramuscularly immunized with the pDsRed2-GRA8 plasmid and then challenged by infection with the highly virulent GFP-RH strain of T. gondii. The specific immune responses and protective efficacy against T. gondii of this vaccine were analyzed by measuring cytokine and serum antibody titers, splenocyte proliferation assays, and the survival times of mice after challenge. Our results showed that mice immunized with pDsRed2-GRA8 demonstrated specific humoral and cellular responses, induced higher IgG antibody titers with predominant IgG2a production; increased levels of IL-10, IL-12 (p70), IFN-γ, TNF-α, and splenocyte proliferation; and prolonged survival times compared to those of control mice. The present study showed that DNA immunization with pDsRed2-GRA8 induced humoral and cellular immune responses, and all immunized mice showed greater Th1-type immune responses and longer survival times than those of control mice. These results indicated that T. gondii GRA8 DNA immunization induces a partial protective effect against acute toxoplasmosis.
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Antígenos de Protozoos/genética , Antígenos de Protozoos/inmunología , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/inmunología , Toxoplasma/inmunología , Toxoplasmosis/inmunología , Toxoplasmosis/prevención & control , Vacunas de ADN/inmunología , Enfermedad Aguda , Animales , Anticuerpos Antiprotozoarios/sangre , Proliferación Celular , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina G/sangre , Ratones Endogámicos BALB C , Bazo/citología , Bazo/inmunologíaRESUMEN
We did a meta-analysis to assess the association between ABCA7 rs3764650 polymorphism and the risk of Alzheimer's Disease (AD). A total of 10 eligible studies with 20511 patients and 40503 controls met the inclusion criteria. ABCA7 rs3764650 polymorphism was significantly associated with AD risk (OR=1.21, 95% CI 1.16-1.26, P<0.00001; I2=5%). In the subgroup analysis by race, statistically significant associations were found in Asians (OR=1.09, 95% CI 1.01-1.18, P =0.03; I2=0%) and in Caucasians (OR=1.25, 95% CI 1.19-1.31, P<0.00001; I2=0%). In conclusion, this meta-analysis suggested that ABCA7 rs3764650 polymorphism is significantly associated with AD risk.
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Transportadoras de Casetes de Unión a ATP/genética , Enfermedad de Alzheimer/genética , Predisposición Genética a la Enfermedad , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/etnología , Pueblo Asiatico/genética , Humanos , Polimorfismo Genético , Riesgo , Población Blanca/genéticaRESUMEN
We investigate encoding and decoding of two-dimensional information using the orbital angular momentum (OAM) of light. Spiral phase plates and phase-only spatial light modulators are used in encoding and decoding of OAM states, respectively. We show that off-axis points and spatial variables encoded with a given OAM state can be recovered through decoding with the corresponding complimentary OAM state.
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Toxoplasma gondii is an obligate intracellular parasite that stimulates production of high levels of proinflammatory cytokines, which are important for innate immunity. NLRs, i.e., nucleotide-binding oligomerization domain (NOD)-like receptors, play a crucial role as innate immune sensors and form multiprotein complexes called inflammasomes, which mediate caspase-1-dependent processing of pro-IL-1ß. To elucidate the role of inflammasome components in T. gondii-infected THP-1 macrophages, we examined inflammasome-related gene expression and mechanisms of inflammasome-regulated cytokine IL-1ß secretion. The results revealed a significant upregulation of IL-1ß after T. gondii infection. T. gondii infection also upregulated the expression of inflammasome sensors, including NLRP1, NLRP3, NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and NAIP, in a time-dependent manner. The infection also upregulated inflammasome adaptor protein ASC and caspase-1 mRNA levels. From this study, we newly found that T. gondii infection regulates NLRC4, NLRP6, NLRP8, NLRP13, AIM2, and neuronal apoptosis inhibitor protein (NAIP) gene expressions in THP-1 macrophages and that the role of the inflammasome-related genes may be critical for mediating the innate immune responses to T. gondii infection.
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Expresión Génica , Inflamasomas/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/inmunología , Macrófagos/parasitología , Proteínas NLR/metabolismo , Toxoplasma/inmunología , Línea Celular , Perfilación de la Expresión Génica , Humanos , Inmunidad Innata , Inflamasomas/genética , Proteínas NLR/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Regulación hacia ArribaRESUMEN
Apoptosis of osteoblasts induced by glucocorticoid (GC) has been identified as a main cause of osteoporosis, bone loss and fractures, and the oxidative stress was found as an important contributor. Therefore, natural or synthetic agents with antioxidant activities can antagonize GCs-induced apoptosis in osteoblasts, and thus demonstrate the potential application to reverse osteoporosis. In this study, we showed that, indole-3-carbinol (I3C), a natural product found in broadly consumed plants of the Brassica genus, could block the cytotoxic effects of dexamethasone (Dex), and elucidated the underlying molecular mechanisms. Firstly, we showed that, I3C could effectively suppress Dex-induced cytotoxicity and apoptotic cell death in osteoblastic cells, as evidenced by the decrease in Sub-G1 cell population. Treatment of the cells with Dex resulted in activation of caspase-3/-8/-9 and subsequent cleavage of PARP, which was also effectively blocked by co-incubation of I3C. Moreover, exposure to Dex triggered a rapid onset and time-dependent superoxide overproduction in osteoblastic cells, which was effectively suppressed by addition of I3C. Excess intracellular ROS induced by Dex significantly suppressed the expression levels of Nrf2 and the downstream effectors, HO1 and NQO1, but these changes could be reversed by I3C. Knockdown of Nrf2 using siRNA silencing technique significantly reversed the protective effects of I3C against Dex-induced apoptosis and ROS generation. Taken together, I3C can reverse cytotoxicity of Dex through blocking ROS overproduction and enhancement of Nrf2 expression. This study may provide a safe and good strategy for molecular intervention of GCs-induced osteoporosis by using natural products.
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Apoptosis/efectos de los fármacos , Dexametasona/farmacología , Indoles/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Osteoblastos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Células 3T3 , Animales , Silenciador del Gen , Ratones , Factor 2 Relacionado con NF-E2/genética , Osteoblastos/citología , Osteoblastos/metabolismoRESUMEN
A novel series of tacrine derivatives were designed and synthesized by combining caffeic acid (CA), ferulic acid (FA) and lipoic acid (LA) with tacrine. The antioxidant study revealed that all the hybrids have much more antioxidant capacities compared to CA. Among these compounds, 1b possessed a good ability to inhibit the ß-amyloid protein (Aß) self-aggregation, sub-micromole acetylcholinesterase (AChE)/butyrylcholinesterase (BuChE) inhibitory, modest BACE1 inhibitory. Moreover, compound 1b also was a DPPH radical scavenger and copper chelatory as well as had potent neuroprotective effects against glutamate-induced cell death with low toxicity in HT22 cells. Our findings suggest that the compound 1b might be a promising lead multi-targeted ligand and worthy of further developing for the therapy of Alzheimer's disease.
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Enfermedad de Alzheimer/tratamiento farmacológico , Tacrina/análogos & derivados , Tacrina/farmacología , Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/metabolismo , Ácidos Cafeicos/química , Línea Celular , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/farmacología , Ácidos Cumáricos/química , Diseño de Fármacos , Humanos , Modelos Moleculares , Relación Estructura-Actividad , Tacrina/síntesis química , Ácido Tióctico/químicaRESUMEN
INTRODUCTION: Does an elevation in d-Galactose (D-Gal) levels within the body contribute to abnormal embryonic development and placental dysfunction during pregnancy? METHODS: Mouse embryos were cultivated to the blastocyst stage under varying concentrations of D-Gal. The blastocyst formation rate was measured, and the levels of reactive oxygen species (ROS), sirtuin 1 (SIRT1), and forkhead box O3a (FOXO3a) in blastocysts were assessed. Mice were intraperitoneally injected with either saline or D-Gal with or without SRT1720. On the 14th day of pregnancy, the fetal absorption rate and placental weight were recorded. Placental levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. The expression of senescence-related factors, such as senescence-associated ß-galactosidase (SA-ß-gal) in the placenta was examined, and the expression of placental SIRT1, FOXO3a and p21 was evaluated by immunohistochemistry and Western blotting. RESULTS: D-Gal adversely affects early embryonic development in vitro, resulting in a decreased blastocyst formation rate. Furthermore, D-Gal downregulates SIRT1 and FOXO3a while increasing ROS levels in blastocysts. Concurrently, D-Gal induces placental dysfunction, characterized by an elevated fetal absorption rate, reduced placental weight, diminished SOD activity, and increased MDA content. The senescence-related factor SA-ß-gal was detected in the placenta, along with altered expression of placental SIRT1, FOXO3a, and p21. The SIRT1 agonist SRT1720 mitigated this damage by increasing SIRT1 and FOXO3a expression. DISCUSSION: The inhibition of early embryonic development and placental dysfunction induced by D-Gal may be attributed to the dysregulation of SIRT1. Activating SIRT1 emerges as a potentially effective strategy for alleviating the adverse effects of D-Gal exposure.
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Desarrollo Embrionario , Proteína Forkhead Box O3 , Galactosa , Placenta , Especies Reactivas de Oxígeno , Sirtuina 1 , Animales , Proteína Forkhead Box O3/metabolismo , Femenino , Sirtuina 1/metabolismo , Embarazo , Especies Reactivas de Oxígeno/metabolismo , Ratones , Desarrollo Embrionario/efectos de los fármacos , Placenta/metabolismo , Placenta/efectos de los fármacos , Enfermedades Placentarias/metabolismo , Enfermedades Placentarias/inducido químicamenteRESUMEN
BACKGROUND: Bone defects, resulting from substantial bone loss that exceeds the natural self-healing capacity, pose significant challenges to current therapeutic approaches due to various limitations. In the quest for alternative therapeutic strategies, bone tissue engineering has emerged as a promising avenue. Notably, excretory proteins from Toxoplasma gondii (TgEP), recognized for their immunogenicity and broad spectrum of biological activities secreted or excreted during the parasite's lifecycle, have been identified as potential facilitators of osteogenic differentiation in human bone marrow mesenchymal stem cells (hBMSCs). Building on our previous findings that TgEP can enhance osteogenic differentiation, this study investigated the molecular mechanisms underlying this effect and assessed its therapeutic potential in vivo. METHODS: We determined the optimum concentration of TgEP through cell cytotoxicity and cell proliferation assays. Subsequently, hBMSCs were treated with the appropriate concentration of TgEP. We assessed osteogenic protein markers, including alkaline phosphatase (ALP), Runx2, and Osx, as well as components of the BMP/Smad signaling pathway using quantitative real-time PCR (qRT-PCR), siRNA interference of hBMSCs, Western blot analysis, and other methods. Furthermore, we created a bone defect model in Sprague-Dawley (SD) male rats and filled the defect areas with the GelMa hydrogel, with or without TgEP. Microcomputed tomography (micro-CT) was employed to analyze the bone parameters of defect sites. H&E, Masson and immunohistochemical staining were used to assess the repair conditions of the defect area. RESULTS: Our results indicate that TgEP promotes the expression of key osteogenic markers, including ALP, Runx2, and Osx, as well as the activation of Smad1, BMP2, and phosphorylated Smad1/5-crucial elements of the BMP/Smad signaling pathway. Furthermore, in vivo experiments using a bone defect model in rats demonstrated that TgEP markedly promoted bone defect repair. CONCLUSION: Our results provide compelling evidence that TgEP facilitates hBMSC osteogenic differentiation through the BMP/Smad signaling pathway, highlighting its potential as a therapeutic approach for bone tissue engineering for bone defect healing.
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Diferenciación Celular , Células Madre Mesenquimatosas , Osteogénesis , Ratas Sprague-Dawley , Transducción de Señal , Toxoplasma , Células Madre Mesenquimatosas/metabolismo , Osteogénesis/fisiología , Humanos , Animales , Transducción de Señal/fisiología , Diferenciación Celular/fisiología , Masculino , Toxoplasma/fisiología , Ratas , Proteínas Smad/metabolismo , Proteínas Protozoarias/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Células CultivadasRESUMEN
BACKGROUND: Previous studies have confirmed the separate effect of arterial stiffness and obesity on type 2 diabetes; however, the joint effect of arterial stiffness and obesity on diabetes onset remains unclear. OBJECTIVE: This study aimed to propose the concept of arterial stiffness obesity phenotype and explore the risk stratification capacity for diabetes. METHODS: This longitudinal cohort study used baseline data of 12,298 participants from Beijing Xiaotangshan Examination Center between 2008 and 2013 and then annually followed them until incident diabetes or 2019. BMI (waist circumference) and brachial-ankle pulse wave velocity were measured to define arterial stiffness abdominal obesity phenotype. The Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% CI. RESULTS: Of the 12,298 participants, the mean baseline age was 51.2 (SD 13.6) years, and 8448 (68.7%) were male. After a median follow-up of 5.0 (IQR 2.0-8.0) years, 1240 (10.1%) participants developed diabetes. Compared with the ideal vascular function and nonobese group, the highest risk of diabetes was observed in the elevated arterial stiffness and obese group (HR 1.94, 95% CI 1.60-2.35). Those with exclusive arterial stiffness or obesity exhibited a similar risk of diabetes, and the adjusted HRs were 1.63 (95% CI 1.37-1.94) and 1.64 (95% CI 1.32-2.04), respectively. Consistent results were observed in multiple sensitivity analyses, among subgroups of age and fasting glucose level, and alternatively using arterial stiffness abdominal obesity phenotype. CONCLUSIONS: This study proposed the concept of arterial stiffness abdominal obesity phenotype, which could improve the risk stratification and management of diabetes. The clinical significance of arterial stiffness abdominal obesity phenotype needs further validation for other cardiometabolic disorders.
Asunto(s)
Diabetes Mellitus Tipo 2 , Rigidez Vascular , Masculino , Humanos , Persona de Mediana Edad , Femenino , Estudios Longitudinales , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Obesidad Abdominal/complicaciones , Obesidad Abdominal/epidemiología , Índice Tobillo Braquial , Análisis de la Onda del Pulso , Estudios de Cohortes , Obesidad/complicaciones , Obesidad/epidemiologíaRESUMEN
Toxoplasma gondii-infected cells are resistant to various apoptotic stimuli, however, the role of the pro-apoptotic BH3-only Bad protein in T. gondii-imposed inhibition of host cell apoptosis in connection with the phosphoinositide 3-kinase (PI3K)-PKB/Akt pathway was not well delineated. Here, we investigated the signaling patterns of Bad, Bax and PKB/Akt in T. gondii-infected and uninfected THP-1 cells treated with staurosporine (STS) or PI3K inhibitors. STS treatment, without T. gondii infection, reduced the viability of THP-1 cells in proportion to STS concentration and triggered many cellular death events such as caspase-3 and -9 activation, Bax translocation, cytochrome c release from host cell mitochondria into cytosol, and PARP cleavage in the host cell. However, T. gondii infection eliminated the STS-triggered mitochondrial apoptotic events described above. Additionally, T. gondii infection in vitro and in vivo induced the phosphorylation of PKB/Akt and Bad in a parasite-load-dependent manner which subsequently inhibited Bax translocation. The PI3K inhibitors, LY294002 and Wortmannin, both blocked parasite-induced phosphorylation of PKB/Akt and Bad. Furthermore, THP-1 cells pretreated with these PI3K inhibitors showed reduced phosphorylation of Bad in a dose-dependent manner and subsequently failed to inhibit the Bax translocation, also these cells also failed to overcome the T. gondii-imposed inhibition of host cell apoptosis. These data demonstrate that the PI3K-PKB/Akt pathway may be one of the major route for T. gondii in the prevention of host cell apoptosis and T. gondii phosphorylates the pro-apoptotic Bad protein to prevent apoptosis.