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1.
ESC Heart Fail ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38600875

RESUMO

AIMS: Both hypercapnia and hypocapnia are common in patients with acute heart failure (AHF), but the association between partial pressure of arterial carbon dioxide (PaCO2) and AHF prognosis remains unclear. The objective of this study was to investigate the connection between PaCO2 within 24 h after admission to the intensive care unit (ICU) and mortality during hospitalization and at 1 year in AHF patients. METHODS AND RESULTS: AHF patients were enrolled from the Medical Information Mart for Intensive Care IV database. The patients were divided into three groups by PaCO2 values of <35, 35-45, and >45 mmHg. The primary outcome was to investigate the connection between PaCO2 and in-hospital mortality and 1 year mortality in AHF patients. The secondary outcome was to assess the prediction value of PaCO2 in predicting in-hospital mortality and 1 year mortality in AHF patients. A total of 2374 patients were included in this study, including 457 patients in the PaCO2 < 35 mmHg group, 1072 patients in the PaCO2 = 35-45 mmHg group, and 845 patients in the PaCO2 > 45 mmHg group. The in-hospital mortality was 19.5%, and the 1 year mortality was 23.9% in the PaCO2 < 35 mmHg group. Multivariate logistic regression analysis showed that the PaCO2 < 35 mmHg group was associated with an increased risk of in-hospital mortality [hazard ratio (HR) 1.398, 95% confidence interval (CI) 1.039-1.882, P = 0.027] and 1 year mortality (HR 1.327, 95% CI 1.020-1.728, P = 0.035) than the PaCO2 = 35-45 mmHg group. The PaCO2 > 45 mmHg group was associated with an increased risk of in-hospital mortality (HR 1.387, 95% CI 1.050-1.832, P = 0.021); the 1 year mortality showed no significant difference (HR 1.286, 95% CI 0.995-1.662, P = 0.055) compared with the PaCO2 = 35-45 mmHg group. The Kaplan-Meier survival curves showed that the PaCO2 < 35 mmHg group had a significantly lower 1 year survival rate. The area under the receiver operating characteristic curve for predicting in-hospital mortality was 0.591 (95% CI 0.526-0.656), and the 1 year mortality was 0.566 (95% CI 0.505-0.627) in the PaCO2 < 35 mmHg group. CONCLUSIONS: In AHF patients, hypocapnia within 24 h after admission to the ICU was associated with increased in-hospital mortality and 1 year mortality. However, the increase in 1 year mortality may be influenced by hospitalization mortality. Hypercapnia was associated with increased in-hospital mortality.

2.
Acta Biomater ; 177: 1-19, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38336269

RESUMO

The emergence of drug-resistant bacteria has significantly diminished the efficacy of existing antibiotics in the treatment of bacterial infections. Consequently, the need for finding a strategy capable of effectively combating bacterial infections has become increasingly urgent. Photodynamic therapy (PDT) is considered one of the most promising emerging antibacterial strategies due to its non-invasiveness, low adverse effect, and the fact that it does not lead to the development of drug resistance. However, bacteria at the infection sites often exist in the form of biofilm instead of the planktonic form, resulting in a hypoxic microenvironment. This phenomenon compromises the treatment outcome of oxygen-dependent type-II PDT. Compared to type-II PDT, type-I PDT is not constrained by the oxygen concentration in the infected tissues. Therefore, in the treatment of bacterial infections, type-I PDT exhibits significant advantages over type-II PDT. In this review, we first introduce the fundamental principles of type-I PDT in details, including its physicochemical properties and how it generates reactive oxygen species (ROS). Next, we explore several specific antimicrobial mechanisms utilized by type-I PDT and summarize the recent applications of type-I PDT in antimicrobial treatment. Finally, the limitations and future development directions of type-I photosensitizers are discussed. STATEMENT OF SIGNIFICANCE: The misuse and overuse of antibiotics have accelerated the development of bacterial resistance. To achieve the effective eradication of resistant bacteria, pathfinders have devised various treatment strategies. Among these strategies, type I photodynamic therapy has garnered considerable attention owing to its non-oxygen dependence. The utilization of non-oxygen-dependent photodynamic therapy not only enables the effective elimination of drug-resistant bacteria but also facilitates the successful eradication of hypoxic biofilms, which exhibits promising prospects for treating biofilm-associated infections. Based on the current research status, we anticipate that the novel type I photodynamic therapy agent can surmount the biofilm barrier, enabling efficient treatment of hypoxic biofilm infections.


Assuntos
Infecções Bacterianas , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Infecções Bacterianas/tratamento farmacológico , Oxigênio
4.
Am J Epidemiol ; 192(12): 1981-1990, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37431780

RESUMO

Diverse manifestations of biological aging often reflect disparities in socioeconomic status (SES). In this paper, we examine associations between indicators of SES and an mRNA-based aging signature during young adulthood, before clinical indications of aging are common. We use data from wave V (2016-2018) of the National Longitudinal Study of Adolescent to Adult Health, a nationally representative study of adults aged 33-43 years, with transcriptomic data from a subset of 2,491 participants. Biological aging is measured using 1) a composite transcriptomic aging signature previously identified by Peters et al.'s out-of-sample meta-analysis (Nat Commun. 2015;6:8570) and 2) 9 subsets that represent functional pathways of coexpressed genes. SES refers to income, education, occupation, subjective social status, and a composite measure combining these 4 dimensions. We examine hypothesized mechanisms through which SES could affect aging: body mass index, smoking, health insurance status, difficulty paying bills, and psychosocial stress. We find that SES-especially the composite measure and income-is associated with transcriptomic aging and immune, mitochondrial, ribosomal, lysosomal, and proteomal pathways. Counterfactual mediational models suggest that the mediators partially account for these associations. The results thus reveal that numerous biological pathways associated with aging are already linked to SES in young adulthood.


Assuntos
Envelhecimento , Classe Social , Adulto , Adolescente , Humanos , Adulto Jovem , Estudos Longitudinais , Envelhecimento/genética , Fumar , Renda , Fatores Socioeconômicos
5.
J Colloid Interface Sci ; 649: 826-831, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37390530

RESUMO

Highly site-specific growth of gold nanoparticles (AuNPs) on Bismuth Selenide (Bi2Se3) hexagonal nanoplates was achieved by fine-tuning the growth kinetics of Au through controlling the coordination number of the Au ion in MBIA-Au3+ complex. With increasing concentration of MBIA, the increased amount and the coordination number of the MBIA-Au3+ complex results in the decrease of the reduction rate of Au. The slowed growth kinetics of Au allowed the recognition of the sites with different surface energy on the anisotropic Bi2Se3 hexagonal nanoplates. As a result, the site-specific growth of AuNPs at the corner, the edge, and the surface of the Bi2Se3 nanoplates were successfully achieved. This way of growth kinetic control was proven to be effective in constructing well-defined heterostructures with precise site-specificity and high purity of the product. This is helpful for the rational design and controlled synthesis of sophisticated hybrid nanostructures and would eventually promote their applications in various fields.

6.
Small ; 19(29): e2300587, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37035961

RESUMO

Precise structural control has attracted tremendous interest in pursuit of the tailoring of physical properties. Here, this work shows that through strong ligand-mediated interfacial energy control, Au-Cu2 O dumbbell structures where both the Au nanorod (AuNR) and the partially encapsulating Cu2 O domains are highly crystalline. The synthetic advance allows physical separation of the Au and Cu2 O domains, in addition to the use of long nanorods with tunable absorption wavelength, and the crystalline Cu2 O domain with well-defined facets. The interplay of plasmon and Schottky effects boosts the photocatalytic performance in the model photodegradation of methyl orange, showing superior catalytic efficiency than the AuNR@Cu2 O core-shell structures. In addition, compared to the typical core-shell structures, the AuNR-Cu2 O dumbbells can effectively electrochemically catalyze the CO2 to C2+ products (ethanol and ethylene) via a cascade reaction pathway. The excellent dual function of both photo- and electrocatalysis can be attributed to the fine physical separation of the crystalline Au and Cu2 O domains.

7.
Small ; 19(29): e2207907, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37052515

RESUMO

The localized surface plasmon resonance (LSPR) is one of the important properties for noble metal nanoparticles. Tuning the LSPR on demand thus has attracted tremendous interest. Beyond the size and shape control, manipulating intraparticle coupling is an effective way to tailor their LSPR. The charge transfer plasmon (CTP) is the most important mode of conductive coupling between subunits linked by conductive bridges that are well studied for structures prepared on substrates by lithography method. However, the colloidal synthesis of CTP structure remains a great challenge. This work reports the colloidal synthesis of extraordinary bridged Au core-satellite structures by exploiting the buffer effect of polydopamine shell on Au core for Au atom diffusion, in which the Au bridge is well controlled in terms of width and length. Benefiting from the tunable Au bridges, the resonance energy of the CTP can be readily controlled. As a result, the LSPR absorptions of the core-satellite structures are continuously tuned within the NIR spectral range (from 900 to >1300 nm), demonstrating their great potentials for ultrafast nano-optics and biomedical applications.

8.
Front Chem ; 11: 1138932, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762190

RESUMO

Hybrid nanostructures have garnered considerable interest because of their fascinating properties owing to the hybridization of materials and their structural varieties. In this study, we report the synthesis of [Au@Rh(OH)3]-Au island heterostructures using a seed-mediated sequential growth method. Through the thiol ligand-mediated interfacial energy, Au@Rh(OH)3 core-shell structures with varying shell thicknesses were successfully obtained. On these Au@Rh(OH)3 core-shell seeds, by modulating the diffusion of HAuCl4 in the porous Rh(OH)3 shell, site-specific growth of Au islands on the inner Au core or on the surface of the outer Rh(OH)3 shell was successfully achieved. Consequently, two types of distinct structures, the Au island-on-[Au@Rh(OH)3] dimer and Au island-Au bridge-[Au@Rh(OH)3] dumbbell structures with thin necks were obtained. Further modulations of the growth kinetics led to the formation of Au plate-Au bridge-[Au@Rh(OH)3] heterostructures with larger structural anisotropy. The flexible structural variations were demonstrated to be an effective means of modulating the plasmonic properties; the Au-Au heterostructures exhibited tunable localized surface plasmon resonance in the visible-near-infrared spectral region and can be used as surface-enhanced Raman scattering (SERS) substrates capable of emitting strong SERS signals. This diffusion-controlled growth of Au bridges in the Rh(OH)3 shells (penetrating growth) is an interesting new approach for structural control, which enriches the tool box for colloidal nanosynthesis. This advancement in structural control is expected to create new approaches for colloidal synthesis of sophisticated nanomaterials, and eventually enable their extensive applications in various fields.

9.
Nat Plants ; 9(2): 201-202, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36658392
10.
Plant Cell ; 35(2): 874-888, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36427255

RESUMO

The endosperm is a nutritive tissue supporting embryo growth in flowering plants. Most commonly, the endosperm initially develops as a coenocyte (multinucleate cell) and then cellularizes. This process of cellularization is frequently disrupted in hybrid seeds generated by crosses between different flowering plant species or plants that differ in ploidy, resulting in embryo arrest and seed lethality. The reason for embryo arrest upon cellularization failure remains unclear. In this study, we show that triploid Arabidopsis thaliana embryos surrounded by uncellularized endosperm mount an osmotic stress response that is connected to increased levels of abscisic acid (ABA) and enhanced ABA responses. Impairing ABA biosynthesis and signaling aggravated triploid seed abortion, while increasing endogenous ABA levels as well as the exogenous application of ABA-induced endosperm cellularization and suppressed embryo growth arrest. Taking these results together, we propose that endosperm cellularization is required to establish dehydration tolerance in the developing embryo, ensuring its survival during seed maturation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Endosperma/genética , Endosperma/metabolismo , Proteínas de Arabidopsis/metabolismo , Triploidia , Desidratação , Arabidopsis/metabolismo , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas/genética
11.
IEEE Trans Pattern Anal Mach Intell ; 45(2): 2088-2103, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35294345

RESUMO

Recent image captioning models are achieving impressive results based on popular metrics, i.e., BLEU, CIDEr, and SPICE. However, focusing on the most popular metrics that only consider the overlap between the generated captions and human annotation could result in using common words and phrases, which lacks distinctiveness, i.e., many similar images have the same caption. In this paper, we aim to improve the distinctiveness of image captions via comparing and reweighting with a set of similar images. First, we propose a distinctiveness metric-between-set CIDEr (CIDErBtw) to evaluate the distinctiveness of a caption with respect to those of similar images. Our metric reveals that the human annotations of each image in the MSCOCO dataset are not equivalent based on distinctiveness; however, previous works normally treat the human annotations equally during training, which could be a reason for generating less distinctive captions. In contrast, we reweight each ground-truth caption according to its distinctiveness during training. We further integrate a long-tailed weight strategy to highlight the rare words that contain more information, and captions from the similar image set are sampled as negative examples to encourage the generated sentence to be unique. Finally, extensive experiments are conducted, showing that our proposed approach significantly improves both distinctiveness (as measured by CIDErBtw and retrieval metrics) and accuracy (e.g., as measured by CIDEr) for a wide variety of image captioning baselines. These results are further confirmed through a user study.

12.
Proc Natl Acad Sci U S A ; 119(43): e2103088119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252037

RESUMO

Many common chronic diseases of aging are negatively associated with socioeconomic status (SES). This study examines whether inequalities can already be observed in the molecular underpinnings of such diseases in the 30s, before many of them become prevalent. Data come from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a large, nationally representative sample of US subjects who were followed for over two decades beginning in adolescence. We now have transcriptomic data (mRNA-seq) from a random subset of 4,543 of these young adults. SES in the household-of-origin and in young adulthood were examined as covariates of a priori-defined mRNA-based disease signatures and of specific gene transcripts identified de novo. An SES composite from young adulthood predicted many disease signatures, as did income and subjective status. Analyses highlighted SES-based inequalities in immune, inflammatory, ribosomal, and metabolic pathways, several of which play central roles in senescence. Many genes are also involved in transcription, translation, and diverse signaling mechanisms. Average causal-mediated effect models suggest that body mass index plays a key role in accounting for these relationships. Overall, the results reveal inequalities in molecular risk factors for chronic diseases often decades before diagnoses and suggest future directions for social signal transduction models that trace how social circumstances regulate the human genome.


Assuntos
Classe Social , Adolescente , Adulto , Índice de Massa Corporal , Doença Crônica , Humanos , Estudos Longitudinais , RNA Mensageiro , Fatores Socioeconômicos , Adulto Jovem
14.
Expert Rev Pharmacoecon Outcomes Res ; 22(7): 1103-1116, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35711123

RESUMO

OBJECTIVE: The purpose of this research was to create a function for mapping the cancer-specific instrument (FACT-G) to a preference-based measure (EQ-5D-3 L) utility index for health-related quality of life, with utility scores generated using the Chinese value set. METHOD: A cross-sectional study among 243 Chinese patients with cancer was conducted through EQ-5D-3 L and FACT-G questionnaires survey. The EQ-5D-3 L utility index values were predicted based on OLS, GLM, CLAD, and Tobit model regression approaches. The performance and predictive power of each model were also evaluated using r2 and adj- r2, MAE, RMSE, ICC, and MID. Linear equating was used to avoid regression of the OLS model to mean. The model was validated using a 10-fold cross-validation method. RESULTS: Among all regression models for the FACT-G, the OLS 5 model predicted mean EQ-5D-3 L values the best, in terms of model goodness of fit (r2 = 0.6230, MAE = 0.0448, RMSE = 0.0624). The OLS model proved to be the most accurate for the mean, and the linear equating scores were much closer to the observed scores. CONCLUSION: Our results suggest that the best algorithm for FACT-G mapping to EQ-5D-3 L utility index is OLS model, based on the survey of Chinese patients with cancer.


Assuntos
Neoplasias , Qualidade de Vida , Algoritmos , China , Estudos Transversais , Humanos , Neoplasias/terapia , Inquéritos e Questionários
15.
Angew Chem Int Ed Engl ; 60(51): 26483-26488, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34590396

RESUMO

Active center reconstruction is essential for high performance oxygen reduction reaction (ORR) electrocatalysts. Usually, the ORR activity stems from the electronic environment of active sites by charge redistribution. We introduce an asymmetry strategy to adjust the charge distribution of active centers by designing conjugated polymer (CP) catalysts with different degrees of asymmetry. We synthesized asymmetric backbone CP (asy-PB) by modifying B←N coordination bonds and asymmetric sidechain CP (asy-PB-A) with different alkyl chain lengths. Both CPs with backbone and sidechain asymmetry exhibit superior ORR performance to their symmetric counterparts (sy-P and sy-PB). The asy-PB with greater asymmetry shows higher catalytic activity than asy-PB-A with relatively smaller asymmetry. DFT calculations reveal that the increased dipole moment and non-uniform charge distribution caused by asymmetric structure endows the center carbon atom of bipyridine with efficient catalytic activity.

16.
Int J Epidemiol ; 50(5): 1660-1670, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33969390

RESUMO

BACKGROUND: Life-course epidemiology studies people's health over long periods, treating repeated measures of their experiences (usually risk factors) as predictors or causes of subsequent morbidity and mortality. Three hypotheses or models often guide the analyst in assessing these sequential risks: the accumulation model (all measurement occasions are equally important for predicting the outcome), the critical period model (only one occasion is important) and the sensitive periods model (a catch-all model for any other pattern of temporal dependence). METHODS: We propose a Bayesian omnibus test of these three composite models, as well as post hoc decompositions that identify their best respective sub-models. We test the approach via simulations, before presenting an empirical example that relates five sequential measurements of body weight to an RNAseq measure of colorectal-cancer disposition. RESULTS: The approach correctly identifies the life-course model under which the data were simulated. Our empirical cohort study indicated with >90% probability that colorectal-cancer disposition reflected a sensitive process, with current weight being most important but prior body weight also playing a role. CONCLUSIONS: The Bayesian methods we present allow precise inferences about the probability of life-course models given the data and are applicable in realistic scenarios involving causal analysis and missing data.


Assuntos
Acontecimentos que Mudam a Vida , Modelos Estatísticos , Teorema de Bayes , Causalidade , Estudos de Coortes , Humanos , Fatores de Risco
17.
Genes (Basel) ; 12(3)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807066

RESUMO

Seed development needs the coordination of multiple molecular mechanisms to promote correct tissue development, seed filling, and the acquisition of germination capacity, desiccation tolerance, longevity, and dormancy. Heat stress can negatively impact these processes and upon the increase of global mean temperatures, global food security is threatened. Here, we explored the impact of heat stress on seed physiology, morphology, gene expression, and methylation on three stages of seed development. Notably, Arabidopsis Col-0 plants under heat stress presented a decrease in germination capacity as well as a decrease in longevity. We observed that upon mild stress, gene expression and DNA methylation were moderately affected. Nevertheless, upon severe heat stress during seed development, gene expression was intensively modified, promoting heat stress response mechanisms including the activation of the ABA pathway. By analyzing candidate epigenetic markers using the mutants' physiological assays, we observed that the lack of DNA demethylation by the ROS1 gene impaired seed germination by affecting germination-related gene expression. On the other hand, we also observed that upon severe stress, a large proportion of differentially methylated regions (DMRs) were located in the promoters and gene sequences of germination-related genes. To conclude, our results indicate that DNA (de)methylation could be a key regulatory process to ensure proper seed germination of seeds produced under heat stress.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Metilação de DNA , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Proteínas Nucleares/genética , Sequenciamento Completo do Genoma/métodos , Arabidopsis/genética , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Germinação , Resposta ao Choque Térmico , Fenótipo , Regiões Promotoras Genéticas , Sementes/genética , Sementes/crescimento & desenvolvimento , Análise de Sequência de RNA
18.
Bioresour Technol ; 332: 125028, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33813180

RESUMO

This study investigated the impacts of different bulking agents (i.e. garden waste, cornstalks, and spent mushroom substrates) on bacterial structure and functions for gaseous emissions during kitchen waste composting. High-throughput sequencing was integrated with functional Annotation of Prokaryotic Taxa (FAPROTAX) to decipher the bacterial structure and functions. Results show that adding cornstalks constructed a more complex and mutualistic bacterial network to enhance organic biodegradation. This scenario, however, aggravated the emission of ammonia and hydrogen sulphide with the enrichment of the genus Bacillus and Desulfitibacter at the thermophilic stage of composting to facilitate ammonification and sulphur-related respiration, respectively. By contrast, spent mushroom substrates facilitated the proliferation of the genus Pseudomonas to promote nitrate reduction at the cooling stage, leading to considerable emission of nitrous oxide. Compared to these two agents, garden waste contained less easily biodegradable substances to limit bacterial mutualism, thereby reducing gaseous emissions in composting.


Assuntos
Compostagem , Amônia/análise , Jardins , Gases/análise , Óxido Nitroso/análise , Solo
19.
Am J Epidemiol ; 190(8): 1533-1540, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33675221

RESUMO

We examined the way body-weight patterns through the first 4 decades of life relate to gene expression signatures of common forms of morbidity, including cardiovascular disease (CVD), type 2 diabetes (T2D), and inflammation. As part of wave V of the nationally representative National Longitudinal Study of Adolescent to Adult Health (1997-2018) in the United States, mRNA abundance data were collected from peripheral blood (n = 1,132). We used a Bayesian modeling strategy to examine the relative associations between body size at 5 life stages-birth, adolescence, early adulthood, young adulthood, and adulthood-and gene expression-based disease signatures. We compared life-course models that consider critical or sensitive periods, as well as accumulation over the entire period. Our results are consistent with a sensitive-period model when examining CVD and T2D gene expression signatures: Birth weight has a prominent role for the CVD and T2D signatures (explaining 33.1% and 22.1%, respectively, of the total association accounted for by body size), while the most recent adult obesity status (ages 33-39) is important for both of these gene expression signatures (24.3% and 35.1%, respectively). Body size in all life stages was associated with inflammation, consistent with the accumulation model.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Inflamação/epidemiologia , Obesidade/epidemiologia , Transcriptoma , Adolescente , Adulto , Teorema de Bayes , Peso ao Nascer , Índice de Massa Corporal , Doenças Cardiovasculares/genética , Criança , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Recém-Nascido , Inflamação/genética , Estudos Longitudinais , Masculino , Obesidade/genética , RNA Mensageiro , Fatores de Risco , Adulto Jovem
20.
Glycobiology ; 31(4): 492-507, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33043980

RESUMO

In the present study, we studied anti-Alzheimer's disease (AD) activities of chondroitin sulfate (CS) oligosaccharides with different molecular weights. CS from shark cartilage was degraded by a recombinant CS endolyase, chondroitinase ABC I (CHSase ABC I), and CS disaccharide (DP2), tetrasaccharide (DP4), hexasaccharide (DP6), octasaccharide (DP8), decasaccharide (DP10) and dodecasaccharide (DP12) were obtained by separation with gel filtration. Anti-AD activities of CS oligosaccharides were assessed using Aß-injured SH-SY5Y cells and BV2 cells. It was shown that CS oligosaccharides could block Aß-induced oxidative stress, mitochondrial dysfunction and activation of intrinsic apoptotic pathway for SH-SY5Y cells. Furthermore, these activities increased with the increase of molecular weights. For Aß-injured BV2 cells, CS oligosaccharides inhibited oxidative stress, the production of proinflammatory cytokines and the activation of toll-like receptor pathway, and CS DP2 had the best activity among them. In conclusion, CS oligosaccharides suppressed Aß-induced oxidative stress and relevant injury in vitro, and these effects had different relationships with the molecular weights of CS oligosaccharides for different cell lines, which might be caused by different mechanisms.


Assuntos
Sulfatos de Condroitina , Oligossacarídeos , Sulfatos de Condroitina/metabolismo , Dissacarídeos , Peso Molecular , Oligossacarídeos/metabolismo , Estresse Oxidativo
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