Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Ther Drug Monit ; 43(1): 69-78, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33009291

RESUMO

BACKGROUND: With the development of industrialization in human society, ambient pollutants are becoming more harmful to human health. Epidemiological and toxicological studies indicate that a close relationship exists between particulate matter with a diameter ≤2.5 µm (PM2.5) and neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). To further confirm the relationship, we focus on possible relevant mechanisms of oxidative stress and neuroinflammation underlying the association between PM2.5 and neurodegenerative diseases in the review. METHODS: A literature search was performed on the studies about PM2.5 and neurodegenerative diseases via PubMed. A total of 113 articles published were selected, and 31 studies were included. RESULTS: PM2.5 can enter the central nervous system through 2 main pathways, the blood-brain barrier and olfactory neurons. The inflammatory response and oxidative stress are 2 primary mechanisms via which PM2.5 leads to toxicity in the brain. PM2.5 abnormally activates microglia, inducing the neuroinflammatory process. Inflammatory markers such as IL-1ß play an essential role in neurodegenerative diseases such as AD and PD. Moreover, the association between lipid mechanism disorders related to PM2.5 and neurodegenerative diseases has been gaining momentum. CONCLUSIONS: In conclusion, PM2.5 could significantly increase the risk of neurological disorders, such as AD and PD. Furthermore, any policy aimed at reducing air-polluting emissions and increasing air quality would be protective in human beings.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Neurodegenerativas , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Doença de Alzheimer/epidemiologia , Humanos , Doenças Neurodegenerativas/induzido quimicamente , Doenças Neurodegenerativas/epidemiologia , Doença de Parkinson/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise
2.
Neurobiol Dis ; 124: 322-334, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30528256

RESUMO

Neural stem/progenitor cells (NPCs) are known to have potent therapeutic effects in neurological disorders through the secretion of extracellular vesicles (EVs). Despite the therapeutic potentials, the numbers of NPCs are limited in the brain, curbing the further use of EVs in the disease treatment. To overcome the limitation of NPC numbers, we used a three transcription factor (Brn2, Sox2, and Foxg1) somatic reprogramming approach to generate induced NPCs (iNPCs) from mouse fibroblasts and astrocytes. The resulting iNPCs released significantly higher numbers of EVs compared with wild-type NPCs (WT-NPCs). Furthermore, iNPCs-derived EVs (iNPC-EVs) promoted NPC function by increasing the proliferative potentials of WT-NPCs. Characterizations of EV contents through proteomics analysis revealed that iNPC-EVs contained higher levels of growth factor-associated proteins that were predicted to activate the down-stream extracellular signal-regulated kinase (ERK) pathways. As expected, the proliferative effects of iNPC-derived EVs on WT-NPCs can be blocked by an ERK pathway inhibitor. Our data suggest potent therapeutic effects of iNPC-derived EVs through the promotion of NPC proliferation, release of growth factors, and activation of ERK pathways. These studies will help develop highly efficient cell-free therapeutic strategies for the treatment of neurological diseases.


Assuntos
Proliferação de Células/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Vesículas Extracelulares/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Técnicas de Reprogramação Celular/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Transdução de Sinais/fisiologia
3.
Breast Cancer Res Treat ; 175(2): 353-368, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30830488

RESUMO

PURPOSE: Low expression of long intergenic non-coding RNA LINC00472 in breast cancer is associated with aggressive tumors and unfavorable disease outcomes in multiple clinical datasets, but the reasons for these associations were unknown. METHODS: To study the mechanisms underlying the lncRNA's connection to breast cancer, we investigated the molecular targets and regulation of LINC00472 in breast cancer cells, and analyzed relevant molecular features in relation to patient survival. Gene expression profiles of breast cancer cells overexpressing LINC00472 were analyzed for its regulatory pathways and downstream targets. Effects of LINC00472 overexpression on cell behaviors were evaluated in vitro and in vivo. Meta-analysis was performed using online datasets and our own study. RESULTS: Analysis of LINC00472 transcriptome revealed ERα upregulation of LINC00472 expression, and an ERα-binding site in the LINC00472 promoter was identified. Evaluation of LINC00472 overexpression also indicated a possible link between LINC00472 and NF-κB. Cell experiments confirmed that LINC00472 suppressed the phosphorylation of p65 and IκBα through binding to IKKß, inhibiting its phosphorylation. High LINC00472 expression inhibited tumor growth both in vitro and in vivo and suppressed aggressive tumor cell behaviors in vitro. Suppressing LINC00472 expression in ER-positive tumor cells increased cell aggressive behaviors. Tamoxifen treatment of ER-positive cells inhibited ERα and LINC00472 expression and increased p65 and IκBα phosphorylation. Meta-analysis showed that LINC00472 expression were higher in ER-positive than ER-negative tumors and that high expression was associated with better disease outcomes in ER-positive patients. CONCLUSIONS: The study demonstrates that ERα upregulates LINC00472 which suppresses the phosphorylation of NF-κB, and suggests that endocrine treatment may lower LINC00472 and increase NF-κB activities, leading to tumor progression and disease recurrence.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Recidiva Local de Neoplasia/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Células MCF-7 , Camundongos , Pessoa de Meia-Idade , NF-kappa B/genética , Recidiva Local de Neoplasia/patologia , Fosforilação/efeitos dos fármacos , Tamoxifeno/farmacologia , eIF-2 Quinase/genética
4.
Ecotoxicol Environ Saf ; 171: 112-121, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30597315

RESUMO

Epidemiological studies have revealed positive correlation between particulate matter with an aerodynamic diameter of < 2.5 µm (PM2.5) and pulmonary fibrosis (PF). As etiology and pathogenesis of PF have not been fully elucidated, this study was to investigate the potential mechanism by which PM2.5 exposure adversely induced PF in vivo and in vitro. In the present study, 6-week-old C57/BL6J mice were intranasally administrated with PM2.5 (100 µg/day) for 4 weeks. Micro-CT and hematoxylin-eosin (HE) staining analysis showed that lung inflammation and incipient fibrosis symptoms were induced after PM2.5 exposure. The expression of Transforming growth factor-ß1 (TGF-ß1), α-Smooth muscle actin (α-SMA), and Collagen type I (COL1) in mice lung was increased. Upregulation of TGF-ß1 in mice serum was also detected by ELISA after exposure to PM2.5. Moreover, chronic PM2.5 exposure on human bronchial epithelial cell line BEAS-2B cells led to activation of TGF-ß1/SMAD3 pathway, TGF-ß1 excretion and epithelial-mesenchymal transition (EMT), while PM2.5 also triggered the activation of TGF-ß1/SMAD3 pathway, TGF-ß1 excretion as well as differentiation of human pulmonary fibroblast cell line HFL-1 cells, and TGF-ß1 production in mouse macrophage cell line RAW264.7 cells. Furthermore, cell culture medium of PM2.5-treated BEAS-2B and RAW264.7 cells could both activate TGF-ß1/SMAD3 signaling, α-SMA and COL1 upregulation in HFL-1 cells. Therefore, we concluded that PM2.5 could induce PF by targeting pulmonary epithelium, macrophages and fibroblasts, suggesting that PM2.5 was a potent initiator of PF.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Fibrose Pulmonar/induzido quimicamente , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
Cell Physiol Biochem ; 47(3): 1244-1258, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29913439

RESUMO

BACKGROUND/AIMS: Ecological studies have shown that air pollution and prevalence of cigarette smoking are positively correlated. Evidence also suggests a synergistic effect of cigarette smoking and PM2.5 exposure (Environmental Particulate Matter ≤ 2.5 µm in diameter) on lung cancer risk. We aimed to evaluate the interaction between smoking prevalence and PM2.5 pollution in relation to lung cancer mortality and determine its underlying mechanisms in vitro. METHODS: "MOVER" method was used to analyze the interaction between smoking prevalence and PM2.5 pollution in relation to lung cancer mortality. Cell autophagy and malignant behaviors induced by cigarette smoke extract (CSE) and PM2.5 exposure were examined in vitro. Gene expression was examined by qRT-PCR and western blot. RNA and protein interaction was determined using a RNA binding protein immunoprecipitation assay. RESULTS: An increased risk for lung cancer death (RERI (the relative excess risk) =0.28) was observed with a synergistic interaction between cigarette smoking and PM2.5 pollution. Cell migration, invasion, EMT (epithelial-mesenchymal transition) and autophagy were elevated when lung cancer cells were treated with CSE and PM2.5 in combination. A lncRNA, named lung cancer progression-association transcript 1 (LCPAT1), was up-regulated after the treatment of CSE and PM2.5, and knocking down the lncRNA impaired the effect of CSE and PM2.5 on lung cancer cells. In addition, LCPAT1 was shown to bind to RCC2, and RCC2 mediated the effect of LCPAT1 on cell autophagy, migration, invasion and EMT in lung cancer. CONCLUSIONS: Our results suggest that combined exposure to CSE and PM2.5 induces LCPAT1 expression, which up-regulates autophagy, and promotes lung cancer progression via RCC2.


Assuntos
Autofagia , Proteínas Cromossômicas não Histona/metabolismo , Transição Epitelial-Mesenquimal , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Material Particulado/toxicidade , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Fumar/efeitos adversos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino
6.
Biochim Biophys Acta Gen Subj ; 1861(2): 112-125, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27836757

RESUMO

BACKGROUND: Evidence shows that individuals who are under long-term exposure to environmental PM2.5 are at increased risk of lung cancer. Various laboratory experiments also suggest several mechanistic links between PM2.5 exposure and lung carcinogenesis. However, a long non-coding RNA (lncRNA) mediated pathogenic change after PM2.5 exposure and its potential roles in tumorigenesis and disease progression have not been reported. METHODS: Cytotoxicity induced by PM2.5 was assessed by using scanning electron microscopy and transmission electron microscopy. ROS generation, autophagy, and metastasis induced by PM2.5 were detected by using comprehensive approaches. Expression of lncRNA-loc146880 and lc3b (autophagy marker) in A549 cells, lung tissue and serum were determined by RT-PCR and Western blotting. RESULTS: PM2.5 could be internalized into lung cancer cells, resulting in marked increases in ROS levels and autophagy. ROS may be responsible for increased expression of loc146880 which further up-regulates autophagy. Both loc146880 and autophagy could promote lung tumor cell migration, invasion and EMT. In addition, a positive correlation was observed between loc146880 expression and lc3b levels in tumor tissues and serum of lung cancer patients. CONCLUSION: Taken together, our data suggest that PM2.5 exposure induces ROS, which activates loc146880 expression. The lncRNA, in turn, up-regulates autophagy and promotes the malignant behaviors of lung cancer cells. GENERAL SIGNIFICANCE: The results show the toxicological effects of PM2.5 in lung tumor progression and metastasis.


Assuntos
Autofagia/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Invasividade Neoplásica/patologia , Material Particulado/efeitos adversos , RNA Longo não Codificante/genética , Células A549 , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Exposição Ambiental/efeitos adversos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
7.
Apoptosis ; 19(7): 1099-112, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24722831

RESUMO

Our group was the first one reporting that autophagy could be triggered by airborne fine particulate matter (PM) with a mean diameter of less than 2.5 µm (PM2.5) in human lung epithelial A549 cells, which could potentially lead to cell death. In the present study, we further explored the potential interactions between autophagy and apoptosis because it was well documented that PM2.5 could induce apoptosis in A549 cells. Much to our surprise, we found that PM2.5-exposure caused oxidative stress, resulting in activation of multiple cell death pathways in A549 cells, that is, the tumor necrosis factor-alpha (TNF-α)-induced pathway as evidenced by TNF-α secretion and activation of caspase-8 and -3, the intrinsic apoptosis pathway as evidenced by increased expression of pro-apoptotic protein Bax, decreased expression of anti-apoptotic protein Bcl-2, disruption of mitochondrial membrane potential, and activation of caspase-9 and -3, and autophagy as evidenced by an increased number of double-membrane vesicles, accompanied by increases of conversion and punctuation of microtubule-associated proteins light chain 3 (LC3) and expression of Beclin 1. It appears that reactive oxygen species (ROS) function as signaling molecules for all the three pathways because pretreatment with N-acetylcysteine, a scavenger of ROS, almost completely abolished TNF-α secretion and significantly reduced the number of apoptotic and autophagic cells. In another aspect, inhibiting autophagy with 3-methyladenine, a specific autophagy inhibitor, enhanced PM2.5-induced apoptosis and cytotoxicity. Intriguingly, neutralization of TNF-α with an anti-TNF-α special antibody not only abolished activation of caspase-8, but also drastically reduced LC3-II conversion. Thus, the present study has provided novel insights into the mechanism of cytotoxicity and even pathogenesis of diseases associated with PM2.5 exposure.


Assuntos
Apoptose , Células Epiteliais/metabolismo , Pulmão/metabolismo , Material Particulado/efeitos adversos , Adenina/análogos & derivados , Adenina/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular , Células Epiteliais/citologia , Humanos , Pulmão/citologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Sirolimo/farmacologia
8.
Nutrients ; 16(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39064755

RESUMO

Low-grade inflammation (LGI) mainly acted as the mediator of the association of obesity and inflammatory diet with numerous chronic diseases, including neuropsychiatric diseases. However, the evidence about the effect of LGI on brain structure is limited but important, especially in the context of accelerating aging. This study was then designed to close the gap, and we leveraged a total of 37,699 participants from the UK Biobank and utilized inflammation score (INFLA-score) to measure LGI. We built the longitudinal relationships of INFLA-score with brain imaging phenotypes using multiple linear regression models. We further analyzed the interactive effects of specific covariates. The results showed high level inflammation reduced the volumes of the subcortex and cortex, especially the globus pallidus (ß [95% confidence interval] = -0.062 [-0.083, -0.041]), thalamus (-0.053 [-0.073, -0.033]), insula (-0.052 [-0.072, -0.032]), superior temporal gyrus (-0.049 [-0.069, -0.028]), lateral orbitofrontal cortex (-0.047 [-0.068, -0.027]), and others. Most significant effects were observed among urban residents. Furthermore, males and individuals with physical frailty were susceptive to the associations. The study provided potential insights into pathological changes during disease progression and might aid in the development of preventive and control targets in an age-friendly city to promote great health and well-being for sustainable development goals.


Assuntos
Encéfalo , Inflamação , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Envelhecimento/fisiologia , Doença Crônica
9.
Chemosphere ; 362: 142703, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925519

RESUMO

Long-term exposure to high-level ambient PM2.5 was associated with increased risks of brain disorders, while the associations remain uncertain when the exposure is lower than current air quality standards in numerous countries. This study aimed to assess the effects of PM2.5 exposure on the brain system in the population with annual mean concentrations ≤15 µg/m3. We analyzed data from 260,922 participants without preexisting brain diseases at baseline in the UK Biobank. The geographical distribution of PM2.5 in 2010 was estimated by a land use regression model and linked with individual residential address. We investigated associations of ambient PM2.5 with incident neurological (dementia, Parkinson's diseases [PD], epilepsy, and migraine) and psychiatric (major depressive disorder [MDD] and anxiety disorder) diseases through Cox proportional hazard models. We further estimated the links with brain imaging phenotypes by neuroimaging analysis. Results showed that in the population with PM2.5 concentrations ≤15 µg/m3, each interquartile range (IQR, 1.28 µg/m3) increment in PM2.5 was related to incidence risks of dementia, epilepsy, migraine, MDD, and anxiety disorder with hazard ratios of 1.08 (95% confidence interval [CI]: 1.03, 1.13), 1.12 (1.05, 1.20), 1.07 (1.00, 1.13), 1.06 (1.03, 1.09), and 1.05 (1.02, 1.08), respectively. We did not observe a significant association with PD. The association with dementia was stronger among the population with poor cardiovascular health (measured by Life's Essential 8) than the counterpart (P for interaction = 0.037). Likewise, per IQR increase was associated with specific brain imaging phenotypes, including volumes of total brain (ß = -0.036; 95% CI: -0.050, -0.022), white matter (-0.030; -0.046, -0.014), grey matter (-0.030; -0.042, -0.017), respectively. The findings suggest long-term exposure to ambient PM2.5 at low-level still has an adverse impact on the neuro-psychiatric systems. The brain-relevant epidemiological assessment suggests that each country should update the standard for ambient PM2.5 following the World Health Organization Air Quality Guidelines 2021.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Material Particulado , Humanos , Material Particulado/análise , Masculino , Pessoa de Meia-Idade , Feminino , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Idoso , Exposição Ambiental/estatística & dados numéricos , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/efeitos adversos , Encefalopatias/induzido quimicamente , Encefalopatias/epidemiologia , Modelos de Riscos Proporcionais , Demência/epidemiologia , Demência/induzido quimicamente , Encéfalo
10.
Sci One Health ; 3: 100075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39282625

RESUMO

Background: Understanding the global burden of enteric infections is crucial for prioritizing control strategies for foodborne and waterborne diseases. This study aimed to assess the global burden of enteric infections in 2021 and identify risk factors from One Health aspects. Methods: Leveraging the Global Burden of Disease (GBD) 2021 database, the incidence, disability-adjusted life years (DALYs), and deaths of enteric infections and the subtypes were estimated, including diarrheal diseases, typhoid and paratyphoid fever, invasive non-typhoidal Salmonella (iNTS) infections, and other intestinal infectious diseases. The estimates were quantified by absolute number, age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR) and age-standardized DALY rate with 95% uncertainty intervals (UIs). Thirteen pathogens and three risk factors associated with diarrheal diseases were analyzed. Results: In 2021, the global age-standardized DALY rate of enteric infections was 1020.15 per 100,000 popultion (95% UI: 822.70-1259.39 per 100,000 population) with an estimated annual percentage change (EAPC) of -4.11% (95% confidence interval: -4.31% to -3.90%) in 1990-2021. A larger burden was observed in regions with lower Socio-demographic index (SDI) levels. Diarrheal disease was the most serious subtype with Western Sub-Saharan Africa exhibiting the highest age-standardized DALY rate (2769.81 per 100,000 population, 95% UI: 1976.80-3674.41 per 100,000 population). Children under 5 and adults over 65 years suffered more from diarrheal diseases with the former experiencing the highest global age-standardized DALY rate (9382.46 per 100,000 population, 95% UI: 6771.76-13,075.12 per 100,000 population). Rotavirus remained the leading cause of diarrheal diseases despite a cross-year decline in the observed age-standardized DALY rate. Unsafe water, sanitation, and handwashing contributed most to the disease burden. Conclusion: The reduced burden of enteric infections suggested the effectiveness of previous control strategies; however, more efforts should be made in vulnerable regions and populations through a One Health approach.

11.
Nutrients ; 16(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474800

RESUMO

Triglyceride (TG) and atherogenic index of plasma (AIP) have been acknowledged to be risk factors for vascular insults, but their impacts on the brain system remain elusive. To fill in some gaps, we investigated associations of TG and AIP with brain structure, leveraging the UK Biobank database. TG and high-density lipoprotein cholesterol (HDL-C) were examined at baseline and AIP was calculated as log (TG/HDL-C). We build several linear regression models to estimate associations of TG and AIP with volumes of brain grey matter phenotypes. Significant inverse associations of TG and AIP with volumes of specific subcortical traits were observed, among which TG and AIP were most significantly associated with caudate nucleus (TG: ß [95% confidence interval CI] = -0.036 [-0.051, -0.022], AIP: -0.038 [-0.053, -0.023]), thalamus (-0.029 [-0.042, -0.017], -0.032 [-0.045, -0.019]). Higher TG and AIP were also considerably related with reduced cortical structure volumes, where two most significant associations of TG and AIP were with insula (TG: -0.035 [-0.048, -0.022], AIP: -0.038 [-0.052, -0.025]), superior temporal gyrus (-0.030 [-0.043, -0.017], -0.033 [-0.047, -0.020]). Modification effects of sex and regular physical activity on the associations were discovered as well. Our findings show adverse associations of TG and AIP with grey matter volumes, which has essential public health implications for early prevention in neurodegenerative diseases.


Assuntos
Aterosclerose , Adulto , Pessoa de Meia-Idade , Idoso , Humanos , Triglicerídeos , Fatores de Risco , HDL-Colesterol , Encéfalo
12.
Stem Cells ; 30(11): 2571-83, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22987307

RESUMO

Chemokine CXCL12 is widely expressed in the central nervous system and essential for the proper functioning of human neural progenitor cells (hNPCs). Although CXCL12 is known to function through its receptor CXCR4, recent data have suggested that CXCL12 binds to chemokine receptor CXCR7 with higher affinity than to CXCR4. However, little is known about the function of CXCR7 in hNPCs. Using a primary hNPC culture system, we demonstrated that CXCL12 promotes hNPC survival in the events of camptothecin-induced apoptosis or growth factor deprivation, and that this effect requires both CXCR7 and CXCR4. Through fluorescence-activated cell sorting analysis and immunocytochemistry, we determined that CXCR7 is mainly localized in the early endosome, while CXCR4 is more broadly expressed at the cell surface and on both early and recycling endosomes. Furthermore, we found that endocytosis is required for the prosurvival function of CXCL12. Using dual-color total internal reflection fluorescence microscopy and immunoprecipitation, we demonstrated that CXCR7 quickly trafficks to plasma membrane in mediating CXCL12 endocytosis and colocalizes with CXCR4 after CXCL12 treatment. Investigating the molecular mechanisms, we found that ERK1/2 endocytotic signaling pathway is essential for hNPC survival upon apoptotic challenges. Consistent with these findings, a significantly higher number of apoptotic NPCs were found in the developing brain of CXCR7 knockout mice. In conclusion, CXCL12 protects hNPCs from apoptotic challenges through CXCR7- and CXCR4-mediated endocytotic signaling. Since survival of hNPCs is important for neurogenesis, CXCR7 may become a new therapeutic target to properly regulate critical processes of brain development.


Assuntos
Quimiocina CXCL12/fisiologia , Endocitose , Células-Tronco Neurais/fisiologia , Receptores CXCR4/metabolismo , Receptores CXCR/metabolismo , Animais , Apoptose/efeitos dos fármacos , Camptotecina/farmacologia , Sobrevivência Celular , Células Cultivadas , Cérebro/embriologia , Cérebro/metabolismo , Endossomos/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Knockout , Células-Tronco Neurais/metabolismo , Ligação Proteica , RNA Interferente Pequeno/genética , Receptores CXCR/genética , Receptores CXCR/fisiologia , Receptores CXCR4/genética , Receptores CXCR4/fisiologia
13.
Cell Biol Toxicol ; 29(3): 143-57, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23525690

RESUMO

It has been well documented in in vitro studies that ambient airborne particulate matter (PM) with an aerodynamic diameter less than 2.5 µm (PM(2.5)) is capable of inducing oxidative stress, which plays a key role in PM(2.5)-mediated cytotoxicity. Although nuclear factor erythroid-2-related factor 2 (Nrf2) has been shown to regulate the intracellular defense mechanisms against oxidative stress, a potential of the Nrf2-mediated cellular defense against oxidative stress induced by PM(2.5) remains to be determined. This study was aimed to explore the potential signaling pathway of Nrf2-mediated defense mechanisms against PM(2.5)-induced oxidative stress in human type II alveolar epithelial A549 cells. We exposed A549 cells to PM(2.5) particles collected from Beijing at a concentration of 16 µg/cm(2). We observed that PM(2.5) triggered an increase of intracellular reactive oxygen species (ROS) in a time-dependent manner during a period of 2 h exposure. We also found that Nrf2 overexpression suppressed and Nrf2 knockdown increased PM(2.5)-induced ROS generation. Using Western blot and confocal microscopy, we found that PM(2.5) exposure triggered significant translocation of Nrf2 into nucleus, resulting in AKT phosphorylation and significant transcription of ARE-driven phases II enzyme genes, such as NAD(P)H:quinone oxidoreductase (NQO-1), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic subunit (GCLC) in A549 cells. Evaluation of signaling pathways showed that a phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002), but not an ERK 1/2 inhibitor (PD98059) or a p38 MAPK (SB203580), significantly down-regulated PM(2.5)-induced Nrf2 nuclear translocation and HO-1 mRNA expression, indicating PI3K/AKT is involved in the signaling pathway leads to the PM(2.5)-induced nuclear translocation of Nrf2 and subsequent Nrf2-mediated HO-1 transcription. Taken together, our results suggest that PM(2.5)-induced ROS may function as signaling molecules to activate Nrf2-mediated defenses, such as HO-1 expression, against oxidative stress induced by PM(2.5) through the PI3K/AKT signaling pathway.


Assuntos
Células Epiteliais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Material Particulado/farmacologia , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Alvéolos Pulmonares/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos
14.
Nat Cardiovasc Res ; 2(3): 322-333, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39195997

RESUMO

The COVID-19 pandemic has limited the access of patients with cardiovascular diseases to healthcare services, causing excess deaths. However, a detailed analysis of temporal variations of excess cardiovascular mortality during the COVID-19 pandemic has been lacking. Here we estimate time-varied excess cardiovascular deaths (observed deaths versus expected deaths predicted by the negative binomial log-linear regression model) in the United States. From March 2020 to March 2022 there were 90,160 excess cardiovascular deaths, or 4.9% more cardiovascular deaths than expected. Two large peaks of national excess cardiovascular mortality were observed during the periods of March-June 2020 and June-November 2021, coinciding with two peaks of COVID-19 deaths, but the temporal patterns varied by state, age, sex and race and ethnicity. The excess cardiovascular death percentages were 5.7% and 4.0% in men and women, respectively, and 3.6%, 8.8%, 7.5% and 7.7% in non-Hispanic White, Black, Asian and Hispanic people, respectively. Our data highlight an urgent need for healthcare services optimization for patients with cardiovascular diseases in the COVID-19 era.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , COVID-19/mortalidade , COVID-19/epidemiologia , COVID-19/etnologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/etnologia , Estados Unidos/epidemiologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Adulto , Idoso de 80 Anos ou mais , SARS-CoV-2 , Adulto Jovem , Adolescente , Pandemias
15.
Front Endocrinol (Lausanne) ; 14: 1212291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780625

RESUMO

PM2.5 can cause adverse health effects via several pathways, such as inducing pulmonary and systemic inflammation, penetration into circulation, and activation of the autonomic nervous system. In particular, the impact of PM2.5 exposure on the liver, which plays an important role in metabolism and detoxification to maintain internal environment homeostasis, is getting more attention in recent years. In the present study, C57BL/6J mice were randomly assigned and treated with PM2.5 suspension and PBS solution for 8 weeks. Then, hepatic tissue was prepared and identified by metabolomics analysis and transcriptomics analysis. PM2.5 exposure can cause extensive metabolic disturbances, particularly in lipid and amino acids metabolic dysregulation.128 differential expression metabolites (DEMs) and 502 differently expressed genes (DEGs) between the PM2.5 exposure group and control group were detected. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that DEGs were significantly enriched in two disease pathways, non-alcoholic fatty liver disease (NAFLD) and type II diabetes mellitus (T2DM), and three signaling pathways, which are TGF-beta signaling, AMPK signaling, and mTOR signaling. Besides, further detection of acylcarnitine levels revealed accumulation in liver tissue, which caused restricted lipid consumption. Furthermore, lipid droplet accumulation in the liver was confirmed by Oil Red O staining, suggesting hepatic steatosis. Moreover, the aberrant expression of three key transcription factors revealed the potential regulatory effects in lipid metabolic disorders, the peroxisomal proliferative agent-activated receptors (PPARs) including PPARα and PPARγ is inhibited, and the activated sterol regulator-binding protein 1 (SREBP1) is overexpressed. Our results provide a novel molecular and genetic basis for a better understanding of the mechanisms of PM2.5 exposure-induced hepatic metabolic diseases, especially in lipid metabolism.


Assuntos
Diabetes Mellitus Tipo 2 , Transtornos do Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Diabetes Mellitus Tipo 2/complicações , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Transtornos do Metabolismo dos Lipídeos/genética , Material Particulado/toxicidade , Lipídeos
16.
Int J Public Health ; 68: 1606305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37649691

RESUMO

Objectives: To evaluate excess deaths of gastrointestinal, liver, and pancreatic diseases in the United States during the COVID-19 pandemic. Methods: We retrieved weekly death counts from National Vital Statistics System and fitted them with a quasi-Poisson regression model. Cause-specific excess deaths were calculated by the difference between observed and expected deaths with adjustment for temporal trend and seasonality. Demographic disparities and temporal-spatial patterns were evaluated for different diseases. Results: From March 2020 to September 2022, the increased mortality (measured by excess risks) for Clostridium difficile colitis, gastrointestinal hemorrhage, and acute pancreatitis were 35.9%; 24.8%; and 20.6% higher than the expected. For alcoholic liver disease, fibrosis/cirrhosis, and hepatic failure, the excess risks were 1.4-2.8 times higher among younger inhabitants than older inhabitants. The excess deaths of selected diseases were persistently observed across multiple epidemic waves with fluctuating trends for gastrointestinal hemorrhage and fibrosis/cirrhosis and an increasing trend for C. difficile colitis. Conclusion: The persistently observed excess deaths of digestive diseases highlights the importance for healthcare authorities to develop sustainable strategies in response to the long-term circulating of SARS-CoV-2 in the community.


Assuntos
COVID-19 , Clostridioides difficile , Colite , Pancreatopatias , Pancreatite , Estados Unidos/epidemiologia , Humanos , Doença Aguda , Pandemias , SARS-CoV-2 , Cirrose Hepática , Hemorragia Gastrointestinal
17.
Infect Dis Poverty ; 12(1): 88, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737184

RESUMO

BACKGROUND: Food systems instantiate the complex interdependencies across humans, physical environments, and other organisms. Applying One Health approaches for agri-food system transformation, which adopts integrated and unifying approaches to optimize the overall health of humans, animals, plants, and environments, is crucial to enhance the sustainability of food systems. This study develops a potential assessment tool, named the global One Health index-Food Security (GOHI-FS), aiming to evaluate food security performance across countries/territories from One Health perspective and identify relevant gaps that need to be improved for sustainable food systems. METHODS: We comprehensively reviewed existing frameworks and elements of food security. The indicator framework of GOHI-FS was conceptualized following the structure-process-outcome model and confirmed by expert advisory. Publicly available data in 2020 was collected for each indicator. The weighting strategy was determined by the Fuzzy Analytical Hierarchy Process. The data for each indicator was normalized and aggregated by weighted arithmetic mean. Linear regressions were performed to evaluate the associations of GOHI-FS with health and social-economic indicators. RESULTS: The GOHI-FS includes 5 first-level indicators, 19 second-level indicators and 45 third-level indicators. There were 146 countries/territories enrolled for evaluation. The highest average score of first-level indicators was Nutrition (69.8) and the lowest was Government Support and Response (31.3). There was regional heterogeneity of GOHI-FS scores. Higher median scores with interquartile range (IQR) were shown in North America (median: 76.1, IQR: 75.5-76.7), followed by Europe and Central Asia (median: 66.9, IQR: 60.1-74.3), East Asia and the Pacific (median: 60.6, IQR: 55.5-68.7), Latin America and the Caribbean (median: 60.2, IQR: 57.8-65.0), Middle East and North Africa (median: 56.6, IQR: 52.0-62.8), South Asia (median: 51.1, IQR: 46.7-53.8), and sub-Saharan Africa (median: 41.4, IQR: 37.2-46.5). We also found significant associations between GOHI-FS and GDP per capita, socio-demographic index, health expenditure and life expectancy. CONCLUSIONS: GOHI-FS is a potential assessment tool to understand the gaps in food security across countries/territories under the One Health concept. The pilot findings suggest notable gaps for sub-Saharan Africa in numerous aspects. Broad actions are needed globally to promote government support and response for food security.


Assuntos
Saúde Única , Animais , Humanos , Ásia Meridional , Meio Ambiente , Europa (Continente) , Governo
18.
Front Aging Neurosci ; 14: 964429, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408109

RESUMO

Aging is an intricate biological event that occurs in both vertebrates and invertebrates. During the aging process, the brain, a vulnerable organ, undergoes structural and functional alterations, resulting in behavioral changes. The hippocampus has long been known to be critically associated with cognitive impairment, dementia, and Alzheimer's disease during aging; however, the underlying mechanisms remain largely unknown. In this study, we hypothesized that altered metabolic and gene expression profiles promote the aging process in the hippocampus. Behavioral tests showed that exploration, locomotion, learning, and memory activities were reduced in aged mice. Metabolomics analysis identified 69 differentially abundant metabolites and showed that the abundance of amino acids, lipids, and microbiota-derived metabolites (MDMs) was significantly altered in hippocampal tissue of aged animals. Furthermore, transcriptomic analysis identified 376 differentially expressed genes in the aged hippocampus. A total of 35 differentially abundant metabolites and 119 differentially expressed genes, constituting the top 200 correlations, were employed for the co-expression network. The multi-omics analysis showed that pathways related to inflammation, microglial activation, synapse, cell death, cellular/tissue homeostasis, and metabolism were dysregulated in the aging hippocampus. Our data revealed that metabolic perturbations and gene expression alterations in the aged hippocampus were possibly linked to their behavioral changes in aged mice; we also provide evidence that altered MDMs might mediate the interaction between gut and brain during the aging process.

19.
Front Public Health ; 9: 697491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395370

RESUMO

Background: Several recent studies reported a positive (statistical) association between ambient nitrogen dioxide (NO2) and COVID-19 transmissibility. However, considering the intensive transportation restriction due to lockdown measures that would lead to declines in both ambient NO2 concentration and COVID-19 spread, the crude or insufficiently adjusted associations between NO2 and COVID-19 transmissibility might be confounded. This study aimed to investigate whether transportation restriction confounded, mediated, or modified the association between ambient NO2 and COVID-19 transmissibility. Methods: The time-varying reproduction number (Rt ) was calculated to quantify the instantaneous COVID-19 transmissibility in 31 Chinese cities from January 1, 2020, to February 29, 2020. For each city, we evaluated the relationships between ambient NO2, transportation restriction, and COVID-19 transmission under three scenarios, including simple linear regression, mediation analysis, and adjusting transportation restriction as a confounder. The statistical significance (p-value < 0.05) of the three scenarios in 31 cities was summarized. Results: We repeated the crude correlational analysis, and also found the significantly positive association between NO2 and COVID-19 transmissibility. We found that little evidence supported NO2 as a mediator between transportation restriction and COVID-19 transmissibility. The association between NO2 and COVID-19 transmissibility appears less likely after adjusting the effects of transportation restriction. Conclusions: Our findings suggest that the crude association between NO2 and COVID-19 transmissibility is likely confounded by the transportation restriction in the early COVID-19 outbreak. After adjusting the confounders, the association between NO2 and COVID-19 transmissibility appears unlikely. Further studies are warranted to validate the findings in other regions.


Assuntos
COVID-19 , Dióxido de Nitrogênio , Cidades , Controle de Doenças Transmissíveis , Humanos , Dióxido de Nitrogênio/análise , SARS-CoV-2
20.
Transl Neurodegener ; 9: 6, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32071715

RESUMO

The direct reprogramming of somatic cells into induced neural progenitor cells (iNPCs) has been envisioned as a promising approach to overcome ethical and clinical issues of pluripotent stem cell transplantation. We previously reported that astrocyte-derived induced pluripotent stem cells (iPSCs) have more tendencies for neuronal differentiation than fibroblast-derived iPSCs. However, the differences of neurogenic potential between astrocyte-derived iNPCs (AiNPCs) and iNPCs from non-neural origins, such as fibroblast-derived iNPCs (FiNPCs), and the underlying mechanisms remain unclear. Our results suggested that AiNPCs exhibited higher differentiation efficiency, mobility and survival capacities, compared to FiNPCs. The whole transcriptome analysis revealed higher activities of TGFß signaling in AiNPCs, versus FiNPCs, following a similar trend between astrocytes and fibroblasts. The higher neurogenic competence, migration ability, and cell death resistance of AiNPCs could be abrogated using TGFß signaling inhibitor LY2157299. Hence, our study demonstrates the difference between iNPCs generated from neural and non-neural cells, together with the underlying mechanisms, which, provides valuable information for donor cell selection in the reprogramming approach.


Assuntos
Astrócitos/fisiologia , Morte Celular/fisiologia , Movimento Celular/fisiologia , Reprogramação Celular/fisiologia , Fibroblastos/fisiologia , Animais , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais , Pirazóis/farmacologia , Quinolinas/farmacologia , Transcriptoma , Fator de Crescimento Transformador beta/antagonistas & inibidores , Cicatrização
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA