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1.
Arterioscler Thromb Vasc Biol ; 43(1): 92-108, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36412197

RESUMO

BACKGROUND: Hematopoietic stem cell (HSC) therapy has shown promise for tissue regeneration after ischemia. Therefore, there is a need to understand mechanisms underlying endogenous HSCs activation in response to ischemic stress and coordination of angiogenesis and repair. SHP-1 plays important roles in HSC quiescence and differentiation by regulation of TGF-ß1 signaling. TGF-ß1 promotes angiogenesis by stimulating stem cells to secrete growth factors to initiate the formation of blood vessels and later aid in their maturation. We propose that SHP-1 responds to ischemia stress in HSC and progenitor cells (HSPC) via regulation of TGF-ß1. METHODS: A mouse hind limb ischemia model was used. Local blood perfusion in the limbs was determined using laser doppler perfusion imaging. The number of positive blood vessels per square millimeter, as well as blood vessel diameter (µm) and area (µm2), were calculated. Hematopoietic cells were analyzed using flow cytometry. The bone marrow transplantation assay was performed to measure HSC reconstitution. RESULTS: After femoral artery ligation, TGF-ß1 was initially decreased in the bone marrow by day 3 of ischemia, followed by an increase on day 7. This pattern was opposite to that in the peripheral blood, which is concordant with the response of HSC to ischemic stress. In contrast, SHP-1 deficiency in HSC is associated with irreversible activation of HSPCs in the bone marrow and increased circulating HSPCs in peripheral blood following limb ischemia. In addition, there was augmented auto-induction of TGF-ß1 and sustained inactivation of SHP-1-Smad2 signaling, which impacted TGF-ß1 expression in HSPCs in circulation. Importantly, restoration of normal T GF-ß1 oscillations helped in the recovery of limb repair and function. CONCLUSIONS: HSPC-SHP-1-mediated regulation of TGF-ß1 in both bone marrow and peripheral blood is required for a normal response to ischemic stress.


Assuntos
Células-Tronco Hematopoéticas , Fator de Crescimento Transformador beta1 , Camundongos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Isquemia , Extremidade Inferior
2.
Environ Sci Technol ; 57(36): 13658-13668, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37647171

RESUMO

Ionic contaminants such as Cr(VI) pose a challenge for water purification using membrane-based processes. However, existing membranes have low permeability and selectivity for Cr(VI). Therefore, in this study, we prepared an electrically controlled adsorptive membrane (ECAM-L) by coating a loose Cl--doped polypyrrole layer on a carbon nanotube substrate, and we evaluated the performance of ECAM-L for Cr(VI) separation from water. We also used electrochemical quartz crystal microbalance measurements and molecular dynamics and density functional theory calculations to investigate the separation mechanisms. The adsorption and desorption of Cr(VI) could be modulated by varying the electrostatic interactions between ECAM-L and Cr(VI) via potential control, enabling the cyclic use of the ECAM-L without additional additives. Consequently, the oxidized ECAM-L showed high Cr(VI) removal performance (<50 µg/L) and treatment capacity (>3500 L/m2) at a high water flux (283 L/m2/h), as well as reusability after the application of a potential. Our study demonstrates an efficient membrane design for water decontamination that can selectively separate Cr(VI) through a short electric stimulus.


Assuntos
Polímeros , Pirróis , Adsorção , Água
3.
Environ Sci Technol ; 57(45): 17640-17648, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37906121

RESUMO

Membrane technology provides an attractive approach for water purification but faces significant challenges in separating small molecules due to its lack of satisfactory permselectivity. In this study, a polypyrrole-based active membrane with a switchable multi-affinity that simultaneously separates small ionic and organic contaminants from water was created. Unlike conventional passive membranes, the designed membrane exhibits a good single-pass filtration efficiency (>99%, taking 1-naphthylamine and Pb2+ as examples) and high permeability (227 L/m2/h). Applying a reversible potential can release the captured substances from the membrane, thus enabling membrane regeneration and self-cleaning without the need for additives. Advanced characterizations reveal that potential switching alters the orientation of the doped amphipathic molecules with the self-alignment of the hydrophobic alkyl chains or the disordered sulfonate anions to capture the target organic molecules or ions via hydrophobic or electrostatic interactions, respectively. The designed smart membrane holds great promise for controllable molecular separation and water purification.


Assuntos
Polímeros , Purificação da Água , Polímeros/química , Pirróis , Filtração , Eletricidade , Íons
4.
Int J Dent Hyg ; 21(3): 599-610, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36524312

RESUMO

BACKGROUND: Studies on the association between adverse birth outcomes and dental caries in children have shown conflicting results, so the aim of this systematic review and meta-analysis was to investigate the association between adverse birth outcomes and dental caries in children. METHODS: We systematically searched articles in four electronic databases (Web of Science, PubMed, Cochrane Library and Embase) published prior to August 2021. The odds ratio (OR) (or converted OR) and the corresponding 95% confidence intervals (95% CI) were processed. The certainty of evidence was assessed using GRADE's risk bias assessment tool. Random effects model was used for this meta-analysis. RESULTS: A total of thirty-one observational studies met the inclusion criteria. The pooled estimates indicated that children exposed to low birth weight (LBW)/preterm birth (PTB) did not experience higher dental caries in primary teeth. Subgroup analyses showed that children with LBW (OR: 1.30, 95% CI: 1.03-1.63) were prone to have dental caries in primary teeth for cross-sectional studies, but no significant differences for prospective studies. PTB children experienced more primary caries in high-income countries (OR: 1.31, 95% CI: 1.00-1.70) than in low- and middle-income countries. CONCLUSIONS: The current evidence did not suggest a significant association between LBW and dental caries in children for primary teeth. Children with PTB in high-income countries had a higher prevalence of primary dental caries. Further prospective studies should adjust for confounding factors (age, oral health and family finances) to determine the definitive association between LBW/PTB and dental caries.


Assuntos
Cárie Dentária , Complicações na Gravidez , Nascimento Prematuro , Criança , Feminino , Recém-Nascido , Humanos , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Nascimento Prematuro/epidemiologia , Estudos Transversais , Estudos Prospectivos , Recém-Nascido de Baixo Peso
5.
Environ Sci Technol ; 56(6): 3552-3563, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35212521

RESUMO

Photocatalysis provides an impetus for the synergetic removal of Cr(VI) and organic contaminants, but the generation of Cr intermediates and their potential oxidizability may be overlooked in pollutant conversion. Herein, the Cr intermediates in the Cr(VI) reduction process were emphasized in Cr(VI)/bisphenol A (BPA) by using graphitic carbon nitride as a photocatalyst. The active species for BPA photodegradation in the BPA system and Cr(VI)/BPA system suggested that the Cr(VI) reduction process indeed promotes BPA photodegradation. Electron paramagnetic resonance (EPR) of Cr complexes and in situ variable-temperature EPR analysis demonstrated Cr(V) intermediate (g = 1.978) generation in Cr(VI) reduction and its oxidization for BPA degradation in photocatalysis. By adding the electron donor Na2SO3, BPA degradation was induced in Cr(VI)/BPA solution, further confirming the positive effect of Cr(V). Moreover, the difference in BPA degradation products in the BPA/air, Cr(VI)/BPA/air, and Cr(VI)/BPA/Ar systems indirectly explained why the Cr(V) intermediate was involved in BPA degradation. Density functional theory calculations revealed that photogenerated electrons can reduce the free energy (0.98 eV) of converting Cr(VI) into Cr(V), which can facilitate the subsequent Cr(V) oxidation step for BPA degradation. This work contributes to the exploration of the Cr(VI) reduction process and the synergistic removal of organic pollutants in Cr(VI)/organics systems.


Assuntos
Cromo , Poluentes Ambientais , Catálise , Oxirredução , Fotólise
6.
Angew Chem Int Ed Engl ; 61(23): e202201300, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35243747

RESUMO

Low-dimensional (LD) perovskites can effectively passivate and stabilize 3D perovskites for high-performance perovskite solar cells (PSCs). Regards CsPbI3 -based PSCs, the influence of high-temperature annealing on the LD perovskite passivation effect has to be taken into account due to fact the black-phase CsPbI3 crystallization requires high-temperature treatment, however, which has been rarely concerned so far. Here, the thermal stability of LD perovskites based on three hydrophobic organic ammonium salts and their passivation effect toward CsPbI3 and the whole device performance, have been investigated. It is found that, phenyltrimethylammonium iodide (PTAI) and its corresponding LD perovskites exhibit excellent thermal stability. Further investigation reveals that PTAI-based LD perovskites are mainly distributed at grain boundaries, which not only enhances the phase stability of CsPbI3 but also effectively suppresses non-radiative recombination. As a consequence, the champion PSC device based on CsPbI3 exhibits a record efficiency of 21.0 % with high stability.

7.
Int J Mol Sci ; 22(13)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34281260

RESUMO

Males have a higher risk for cardiovascular diseases (CVDs) than females. Ambient fine particulate matter (PM) exposure increases CVD risk with increased reactive oxygen species (ROS) production and oxidative stress. Endothelial progenitor cells (EPCs) are important to vascular structure and function and can contribute to the development of CVDs. The aims of the present study were to determine if sex differences exist in the effect of PM exposure on circulating EPCs in mice and, if so, whether oxidative stress plays a role. Male and female C57BL/6 mice (8-10 weeks old) were exposed to PM or a vehicle control for six weeks. ELISA analysis showed that PM exposure substantially increased the serum levels of IL-6 and IL-1ß in both males and females, but the concentrations were significantly higher in males. PM exposure only increased the serum levels of TNF-α in males. Flow cytometry analysis demonstrated that ROS production was significantly increased by PM treatment in males but not in females. Similarly, the level of circulating EPCs (CD34+/CD133+ and Sca-1+/Flk-1+) was significantly decreased by PM treatment in males but not in females. Antioxidants N-acetylcysteine (NAC) effectively prevented PM exposure-induced ROS and inflammatory cytokine production and restored circulating EPC levels in male mice. In sharp contrast, circulating EPC levels remained unchanged in female mice with PM exposure, an effect that was not altered by ovariectomy. In conclusion, PM exposure selectively decreased the circulating EPC population in male mice via increased oxidative stress without a significant impact on circulating EPCs in females independent of estrogen.


Assuntos
Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Material Particulado/toxicidade , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Citocinas/sangue , Células Progenitoras Endoteliais/patologia , Estrogênios/metabolismo , Feminino , Mediadores da Inflamação/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores Sexuais
8.
Angew Chem Int Ed Engl ; 60(24): 13436-13443, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33792125

RESUMO

Besides widely used surface passivation, engineering the film crystallization is an important and more fundamental route to improve the performance of all-inorganic perovskite solar cells. Herein, we have developed a urea-ammonium thiocyanate (UAT) molten salt modification strategy to fully release and exploit coordination activities of SCN- to deposit high-quality CsPbI3 film for efficient and stable all-inorganic solar cells. The UAT is derived by the hydrogen bond interactions between urea and NH4 + from NH4 SCN. With the UAT, the crystal quality of the CsPbI3 film has been significantly improved and a long single-exponential charge recombination lifetime of over 30 ns has been achieved. With these benefits, the cell efficiency has been promoted to over 20 % (steady-state efficiency of 19.2 %) with excellent operational stability over 1000 h. These results demonstrate a promising development route of the CsPbI3 related photoelectric devices.

9.
J Cell Mol Med ; 24(1): 886-898, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31742908

RESUMO

MG53 is an important membrane repair protein and partially protects bone marrow multipotent adult progenitor cells (MAPCs) against oxidized low-density lipoprotein (ox-LDL). The present study was to test the hypothesis that the limited protective effect of MG53 on MAPCs was due to ox-LDL-induced reduction of MG53. MAPCs were cultured with and without ox-LDL (0-20 µg/mL) for up to 48 hours with or without MG53 and antioxidant N-acetylcysteine (NAC). Serum MG53 level was measured in ox-LDL-treated mice with or without NAC treatment. Ox-LDL induced significant membrane damage and substantially impaired MAPC survival with selective inhibition of Akt phosphorylation. NAC treatment effectively prevented ox-LDL-induced reduction of Akt phosphorylation without protecting MAPCs against ox-LDL. While having no effect on Akt phosphorylation, MG53 significantly decreased ox-LDL-induced membrane damage and partially improved the survival, proliferation and apoptosis of MAPCs in vitro. Ox-LDL significantly decreased MG53 level in vitro and serum MG53 level in vivo without changing MG53 clearance. NAC treatment prevented ox-LDL-induced MG53 reduction both in vitro and in vivo. Combined NAC and MG53 treatment significantly improved MAPC survival against ox-LDL. These data suggested that NAC enhanced the protective effect of MG53 on MAPCs against ox-LDL through preventing ox-LDL-induced reduction of MG53.


Assuntos
Acetilcisteína/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipoproteínas LDL/toxicidade , Proteínas de Membrana/metabolismo , Células-Tronco Multipotentes/efeitos dos fármacos , Fatores de Proteção , Animais , Apoptose , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Ciclo Celular , Proliferação de Células , Sequestradores de Radicais Livres/farmacologia , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/patologia , Ratos
10.
Acta Cardiol Sin ; 36(3): 183-194, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32425433

RESUMO

Calcific aortic valve disease (CAVD) represents a significant threat to cardiovascular health worldwide, and the incidence of this sclerocalcific valve disease has rapidly increased along with a rise in life expectancy. Compelling evidence has suggested that CAVD is an actively and finely regulated pathophysiological process even though it has been referred to as "degenerative" for decades. A striking similarity has been noted in the etiopathogenesis between CAVD and atherosclerosis, a classical proliferative sclerotic vascular disease.1 Nevertheless, pharmaceutical trials that attempted to target inflammation and dyslipidemia have produced disappointing results in CAVD. While senescence is a well-documented risk factor, the sophisticated regulatory networks have not been adequately explored underlying the aberrant calcification and osteogenesis in CAVD. Valvular endothelial cells (VECs), a type of resident effector cells in aortic leaflets, are crucial in maintaining valvular integrity and homeostasis, and dysfunctional VECs are a major contributor to disease initiation and progression. Accumulating evidence suggests that VECs undergo a phenotypic and functional transition to mesenchymal or fibroblast-like cells in CAVD, a process known as the endothelial-to-mesenchymal transition (EndMT) process. The relevance of this transition in CAVD has recently drawn great interest due to its importance in both valve genesis at an embryonic stage and CAVD development at an adult stage. Hence EndMT might be a valuable diagnostic and therapeutic target for disease prevention and treatment. This mini-review summarized the relevant literature that delineates the EndMT process and the underlying regulatory networks involved in CAVD.

11.
J Cell Mol Med ; 23(6): 4019-4029, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30973215

RESUMO

Endothelial progenitor cells (EPCs) are a group of heterogeneous cells in bone marrow (BM) and blood. Ischaemia increases reactive oxygen species (ROS) production that regulates EPC number and function. The present study was conducted to determine if ischaemia-induced ROS differentially regulated individual EPC subpopulations using a mouse model concomitantly overexpressing superoxide dismutase (SOD)1, SOD3 and glutathione peroxidase. Limb ischaemia was induced by femoral artery ligation in male transgenic mice with their wild-type littermate as control. BM and blood cells were collected for EPCs analysis and mononuclear cell intracellular ROS production, apoptosis and proliferation at baseline, day 3 and day 21 after ischaemia. Cells positive for c-Kit+ /CD31+ or Sca-1+ /Flk-1+ or CD34+ /CD133+ or CD34+ /Flk-1+ were identified as EPCs. ischaemia significantly increased ROS production and cell apoptosis and decreased proliferation of circulating and BM mononuclear cells and increased BM and circulating EPCs levels. Overexpression of triple antioxidant enzymes effectively prevented ischaemia-induced ROS production with significantly decreased cell apoptosis and preserved proliferation and significantly increased circulating EPCs level without significant changes in BM EPC populations, associated with enhanced recovery of blood flow and function of the ischemic limb. These data suggested that ischaemia-induced ROS was differentially involved in the regulation of circulating EPC population.


Assuntos
Antioxidantes/metabolismo , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Membro Posterior/metabolismo , Membro Posterior/patologia , Isquemia/metabolismo , Isquemia/patologia , Animais , Apoptose/fisiologia , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Proliferação de Células/fisiologia , Células Cultivadas , Glutationa Peroxidase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/metabolismo , Superóxido Dismutase/metabolismo
12.
J Nanosci Nanotechnol ; 18(4): 2304-2309, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442896

RESUMO

In this study, silver decorated graphene oxide (Ag/GO) composite was fabricated through a reduction process in the presence of potassium borohydride solution. Subsequently, physicochemical properties of the resulting Ag/GO composite were studied by scanning electron microscope, X-ray diffraction, Raman spectra, Fourier transformation infrared spectroscopy and UV-visible diffuse reflectance spectrum. Results indicated that Ag species existed in the form of Ag0, which greatly facilitated the visible light absorbance ability. Furthermore, the performance of Ag/GO was evaluated by PC inactiviation of Escherichia coli under Xenon lamp illumination. It was found that Ag/GO sample could kill the Escherichia coli within 60 min illumination by the non-selective attack of ⋅OH radicals. This study provides a novel and facile strategy to fabricate high-efficient catalyst to kill the bacteria in drinking water treatment.


Assuntos
Escherichia coli , Grafite , Prata , Catálise , Nanocompostos , Óxidos
13.
J Cell Mol Med ; 21(5): 1024-1032, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27957792

RESUMO

Gender differences are present in many diseases and are especially prevalent in cardiovascular disease. Males tend to suffer from myocardial infarctions earlier than females, and a woman's risk of cardiovascular disease increases after menopause, suggesting a cardio-protective role of estrogen. However, hormone replacement therapy did not decrease the risk of cardiovascular disease in post-menopausal women; thus, other mechanisms may be involved besides estrogen. Oxidative stress plays an important role in the development of cardiovascular diseases such as coronary artery disease. Gender is also associated with differences in oxidative stress. Under physiological conditions, females appear to be less susceptible to oxidative stress. This may be due to the antioxidant properties of estrogen, gender differences in NADPH-oxidase activity or other mechanism(s) yet to be defined. This review strives to discuss gender differences in general terms followed by a more detailed examination of gender differences with oxidative stress and various associated diseases and the possible mechanisms underlying these differences.


Assuntos
Doenças Cardiovasculares/patologia , Estresse Oxidativo , Caracteres Sexuais , Antioxidantes/metabolismo , Estrogênios/metabolismo , Feminino , Humanos , Masculino
14.
J Cell Mol Med ; 20(5): 782-93, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26988063

RESUMO

Air pollution is a major challenge to public health. Ambient fine particulate matter (PM) is the key component for air pollution, and associated with significant mortality. The majority of the mortality following PM exposure is related to cardiovascular diseases. However, the mechanisms for the adverse effects of PM exposure on cardiovascular system remain largely unknown and under active investigation. Endothelial dysfunction or injury is considered one of the major factors that contribute to the development of cardiovascular diseases such as atherosclerosis and coronary heart disease. Endothelial progenitor cells (EPCs) play a critical role in maintaining the structural and functional integrity of vasculature. Particulate matter exposure significantly suppressed the number and function of EPCs in animals and humans. However, the mechanisms for the detrimental effects of PM on EPCs remain to be fully defined. One of the important mechanisms might be related to increased level of reactive oxygen species (ROS) and inflammation. Bone marrow (BM) is a major source of EPCs. Thus, the number and function of EPCs could be intimately associated with the population and functional status of stem cells (SCs) in the BM. Bone marrow stem cells and other SCs have the potential for cardiovascular regeneration and repair. The present review is focused on summarizing the detrimental effects of PM exposure on EPCs and SCs, and potential mechanisms including ROS formation as well as clinical implications.


Assuntos
Aterosclerose/etiologia , Células da Medula Óssea/efeitos dos fármacos , Doença das Coronárias/etiologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Exposição Ambiental , Material Particulado/efeitos adversos , Poluição do Ar , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/terapia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Doença das Coronárias/metabolismo , Doença das Coronárias/patologia , Doença das Coronárias/terapia , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Humanos , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo
15.
Cell Physiol Biochem ; 39(1): 89-101, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27322674

RESUMO

BACKGROUND/AIMS: Oxidized low-density lipoprotein (ox-LDL) is a major component of hyperlipidemia and contributes to atherosclerosis. Endothelial progenitor cells (EPCs) play an important role in preventing atherosclerosis and notably decreased in hyperlipidemia. Ox-LDL and ox-LDL-related reactive oxygen species (ROS) have deleterious effects on EPCs. Probucol as an antioxidant and anti-inflammatory drug reduces ROS production. The present study was to determine if probucol could protect EPCs from ox-LDL in vivo and to investigate the potential mechanisms. METHODS: ox-LDL was injected into male C57BL/6 mice for 3 days with or without probucol treatment with PBS as control. Bone marrow (BM) fluid, serum, circulating mononuclear cells (MNCs) and EPCs were collected for analysis. RESULTS: the increased extracellular ROS in BM, serum and blood intracellular ROS production in the mice with ox-LDL treatment in association with a significant reduction of circulating MNCs and EPCs were restored with Probucol treatment. A significant increase in the serum ox-LDL and C-reactive protein and decrease in superoxide dismutase and circulating MNCs and EPCs were observed in hyperlipidemic patients that were effectively reversed with probucol treatment. CONCLUSION: these data suggested that probucol could protect EPCs from ox-LDL through inhibition of ROS production in vivo.


Assuntos
Células Progenitoras Endoteliais/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Probucol/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Proteína C-Reativa/metabolismo , Células Cultivadas , Células Progenitoras Endoteliais/metabolismo , Citometria de Fluxo , Humanos , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Espécies Reativas de Oxigênio/sangue , Superóxido Dismutase/metabolismo
16.
J Hepatol ; 63(6): 1397-404, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26220751

RESUMO

BACKGROUND & AIMS: Hepatic fibrosis, featured by the accumulation of excessive extracellular matrix in liver tissue, is associated with metabolic disease and cancer. Inhalation exposure to airborne particulate matter in fine ranges (PM2.5) correlates with pulmonary dysfunction, cardiovascular disease, and metabolic syndrome. In this study, we investigated the effect and mechanism of PM2.5 exposure on hepatic fibrogenesis. METHODS: Both inhalation exposure of mice and in vitro exposure of specialized cells to PM2.5 were performed to elucidate the effect of PM2.5 exposure on hepatic fibrosis. Histological examinations, gene expression analyses, and genetic animal models were utilized to determine the effect and mechanism by which PM2.5 exposure promotes hepatic fibrosis. RESULTS: Inhalation exposure to concentrated ambient PM2.5 induces hepatic fibrosis in mice under the normal chow or high-fat diet. Mice after PM2.5 exposure displayed increased expression of collagens in liver tissues. Exposure to PM2.5 led to activation of the transforming growth factor ß-SMAD3 signaling, suppression of peroxisome proliferator-activated receptor γ, and expression of collagens in hepatic stellate cells. NADPH oxidase plays a critical role in PM2.5-induced liver fibrogenesis. CONCLUSIONS: Exposure to PM2.5 exerts discernible effects on promoting hepatic fibrogenesis. NADPH oxidase mediates the effects of PM2.5 exposure on promoting hepatic fibrosis.


Assuntos
Cirrose Hepática Experimental/etiologia , Material Particulado/toxicidade , Animais , Colágeno/biossíntese , Células Estreladas do Fígado/metabolismo , Exposição por Inalação , Células de Kupffer/metabolismo , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidases/metabolismo , PPAR gama/metabolismo , Material Particulado/administração & dosagem , Material Particulado/química , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
17.
Cell Physiol Biochem ; 35(1): 353-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25591776

RESUMO

BACKGROUND/AIMS: Bone marrow (BM)-derived endothelial progenitor cells (EPCs) play a critical role in angiogenesis and vascular repair. Some environmental insults, like fine particulate matter (PM) exposure, significantly impair cardiovascular functions. However, the mechanisms for PM-induced adverse effects on cardiovascular system remain largely unknown. The present research was to study the detrimental effects of PM on EPCs and explore the potential mechanisms. METHODS: PM was intranasal-distilled into male C57BL/6 mice for one month. Flow cytometry was used to measure the number of EPCs, apoptosis level of circulating EPCs and intracellular reactive oxygen species (ROS) formation. Serum TNF-α and IL-1ß were measured using ELISA. To determine the role of PM-induced ROS in EPC apoptosis, PM was co-administrated with the antioxidant N-acetylcysteine (NAC) in wild type mice or used in a triple transgenic mouse line (TG) with overexpression of antioxidant enzyme network (AON) composed of superoxide dismutase (SOD)1, SOD3, and glutathione peroxidase (Gpx-1) with decreased in vivo ROS production. RESULTS: PM treatment significantly decreased circulating EPC population, promoted apoptosis of EPCs in association with increased ROS production and serum TNF-α and IL-1ß levels, which could be effectively reversed by either NAC treatment or overexpression of AON. CONCLUSION: PM exposure significantly decreased circulating EPCs population due to increased apoptosis via ROS formation in mice.


Assuntos
Apoptose/efeitos dos fármacos , Material Particulado/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Interleucina-1beta/sangue , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Fator de Necrose Tumoral alfa/sangue
18.
J Cell Mol Med ; 18(12): 2445-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25256620

RESUMO

Cell therapy with bone marrow stem cells (BMSCs) remains a viable option for tissue repair and regeneration. A major challenge for cell therapy is the limited cell survival after implantation. This study was to investigate the effect of oxidized low-density lipoprotein (ox-LDL, naturally present in human blood) on BMSC injury and the effect of MG53, a tissue repair protein, for the improvement of stem cell survival. Rat bone marrow multipotent adult progenitor cells (MAPCs) were treated with ox-LDL, which caused significant cell death as reflected by the increased LDH release to the media. Exposure of MAPCs to ox-LDL led to entry of fluorescent dye FM1-43 measured under confocal microscope, suggesting damage to the plasma membrane. Ox-LDL also generated reactive oxygen species (ROS) as measured with electron paramagnetic resonance spectroscopy. While antioxidant N-acetylcysteine completely blocked ROS production from ox-LDL, it failed to prevent ox-LDL-induced cell death. When MAPCs were treated with the recombinant human MG53 protein (rhMG53) ox-LDL induced LDH release and FM1-43 dye entry were significantly reduced. In the presence of rhMG53, the MAPCs showed enhanced cell survival and proliferation. Our data suggest that membrane damage induced by ox-LDL contributed to the impaired survival of MAPCs. rhMG53 treatment protected MAPCs against membrane damage and enhanced their survival which might represent a novel means for improving efficacy for stem cell-based therapy for treatment of diseases, especially in setting of hyperlipidemia.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Células-Tronco Multipotentes/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Células da Medula Óssea/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/farmacologia , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Corantes Fluorescentes/metabolismo , Corantes Fluorescentes/farmacocinética , Sequestradores de Radicais Livres/farmacologia , Humanos , Microscopia Confocal , Células-Tronco Multipotentes/metabolismo , Compostos de Piridínio/metabolismo , Compostos de Piridínio/farmacocinética , Compostos de Amônio Quaternário/metabolismo , Compostos de Amônio Quaternário/farmacocinética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Proteínas com Motivo Tripartido
19.
Front Immunol ; 15: 1386382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585270

RESUMO

Xenotransplantation is emerging as a vital solution to the critical shortage of organs available for transplantation, significantly propelled by advancements in genetic engineering and the development of sophisticated immunosuppressive treatments. Specifically, the transplantation of kidneys from genetically engineered pigs into human patients has made significant progress, offering a potential clinical solution to the shortage of human kidney supply. Recent trials involving the transplantation of these modified porcine kidneys into deceased human bodies have underscored the practicality of this approach, advancing the field towards potential clinical applications. However, numerous challenges remain, especially in the domains of identifying suitable donor-recipient matches and formulating effective immunosuppressive protocols crucial for transplant success. Critical to advancing xenotransplantation into clinical settings are the nuanced considerations of anesthesia and surgical practices required for these complex procedures. The precise genetic modification of porcine kidneys marks a significant leap in addressing the biological and immunological hurdles that have traditionally challenged xenotransplantation. Yet, the success of these transplants hinges on the process of meticulously matching these organs with human recipients, which demands thorough understanding of immunological compatibility, the risk of organ rejection, and the prevention of zoonotic disease transmission. In parallel, the development and optimization of immunosuppressive protocols are imperative to mitigate rejection risks while minimizing side effects, necessitating innovative approaches in both pharmacology and clinical practices. Furthermore, the post-operative care of recipients, encompassing vigilant monitoring for signs of organ rejection, infectious disease surveillance, and psychological support, is crucial for ensuring post-transplant life quality. This comprehensive care highlights the importance of a multidisciplinary approach involving transplant surgeons, anesthesiologists, immunologists, infectiologists and psychiatrists. The integration of anesthesia and surgical expertise is particularly vital, ensuring the best possible outcomes of those patients undergoing these novel transplants, through safe procedural practices. As xenotransplantation moving closer to clinical reality, establishing consensus guidelines on various aspects, including donor-recipient selection, immunosuppression, as well as surgical and anesthetic management of these transplants, is essential. Addressing these challenges through rigorous research and collective collaboration will be the key, not only to navigate the ethical, medical, and logistical complexities of introducing kidney xenotransplantation into mainstream clinical practice, but also itself marks a new era in organ transplantation.


Assuntos
Anestesia , Transplante de Órgãos , Animais , Humanos , Suínos , Transplante Heterólogo/efeitos adversos , Zoonoses , Rim , Imunossupressores
20.
Sci Adv ; 10(21): eadn8696, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787943

RESUMO

Drinking water with micropollutants is a notable environmental concern worldwide. Membrane separation is one of the few methods capable of removing micropollutants from water. However, existing membranes face challenges in the simultaneous and efficient treatment of small-molecular and ionic contaminants because of their limited permselectivity. Here, we propose a high-efficiency water purification method using a low-pressure Janus membrane with electro-induced multi-affinity. By virtue of hydrophobic and electrostatic interactions between the functional interfaces and contaminants, the Janus membrane achieves simultaneous separation of diverse types of organics and heavy metals from water via single-pass filtration, with an approximately 100% removal efficiency, high water flux (>680 liters m-2 hour-1), and 98% lower energy consumption compared with commercial nanofiltration membranes. The electro-induced switching of interfacial affinity enables 100% regeneration of membrane performance; thus, our work paves a sustainable avenue for drinking water purification by regulating the interfacial affinity of membranes.

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