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1.
Water Res ; 264: 122240, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39146854

RESUMO

The release of rubber-derived chemicals (RDCs) in road surface runoff has received significant attention. Urban surface runoff is often the confluence of stormwater runoff from specific areas. However, the impact of precipitation on RDCs contamination in confluent stormwater runoff and receiving watersheds remains poorly understood. Herein, we investigated the profiles of RDCs and their transformation products in confluent stormwater runoff and receiving rivers affected by precipitation events. The results showed that 34 RDCs are ubiquitously present in confluent stormwater runoff and surface water, with mean concentrations of 1.03-2749 and 0.28-436 ng/L, respectively. The most dominant target compounds in each category were N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone, 2-benzothiazolol, and 1,3-diphenylguanidine. Total RDCs concentrations in confluent stormwater runoff decreased spatially from industrial areas to business districts to college towns. A significant decrease in RDCs levels in surface water after rainfall was observed (P < 0.01), indicating that precipitation contributes to alleviating RDCs pollution in receiving watersheds. To our knowledge, this is the first report of N,N'-ditolyl-p-phenylenediamine quinone (DTPD-Q) levels in surface waters in China. The annual mass load of ∑RDCs reached 72,818 kg/y in confluent stormwater runoff, while 38,799 kg/y in surface water. The monitoring of confluent stormwater runoff is an efficient measure for predicting contamination loads from RDCs in rivers. Risk assessment suggested that most RDCs posed at least medium risks to aquatic organisms, especially 6PPD-quinone. The findings help to understand the environmental fate and risks of RDCs in the confluent stormwater runoff and receiving environments after precipitation events.

2.
ACS Nano ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145659

RESUMO

Solid polymer electrolytes (SPEs) represent a pivotal advance toward high-energy solid-state lithium metal batteries. However, inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Inadequate interfacial contact remains a significant bottleneck, impeding scalability and application. Recent efforts have focused on transforming liquid/solid interfaces into solid/solid ones through in situ polymerization, which shows potential especially in reducing interface impedance. Here, we designed high-voltage SSLMBs with dual-reinforced stable interfaces by combining interface modification with an in situ polymerization technology inspired by targeted effects in medicine. Theoretical calculations and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis demonstrate that tetramethylene sulfone (TMS) and bis(2,2,2-trifluoromethyl) carbonate (TFEC) exhibit selective adsorption at the interface of the LiNi0.8Co0.1Mn0.1O2 (NCM) cathode and Li anode, respectively. These compounds further decompose to form a stable cathode-electrolyte interface (CEI) film and a solid electrolyte interface (SEI) film, thereby simultaneously achieving a superior interface between the SPE and both the Li anode and NCM cathode. The developed Li||SPE||Li cell sustained cycling for more than 1000 h at 0.3 mA cm-2, and the NCM||SPE||Li cell also demonstrated an excellent capacity retention of 86.8% after 1000 cycles at 1 °C. This work will provide valuable insights for the rational design of high-voltage SSLMBs with stable interfaces, leveraging in situ polymerization as a cornerstone technology.

4.
Placenta ; 155: 78-87, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39154487

RESUMO

INTRODUCTION: An early evaluating system for autism spectrum disorder (ASD) severity is crucial. Questionnaire survey is challenging for accurately assessing the severity levels for ASD in children. METHODS: Offspring with ASD-like phenotypes were induced by treating pregnant mice with Poly (I:C) at GD12.5 and the placentae corresponding to the offspring were obtained by caesarean. The autism severity composite score (ASCS) for offspring was calculated through behavioral tests. HE staining and immunohistochemistry were used to observe the morphology of placenta. Candidate biomarkers were identified by weighted protein co-expression network analysis (WPCNA) combined with machine learning and further validated by ELISA. Sperman's was used to analyze the correlation between biomarkers and metabolome. RESULTS: The placental weight and mean vascular area of male offspring with ASD-like phenotypes were significantly decreased compared with typical mice. According to the WPCNA, four modules were identified and significantly correlated with ASCS of offspring. Two biomarkers (ASPG and DAD1) with high correlation with ASCS in offspring were identified. DISCUSSION: VEGF pathway may contribute to sexual dimorphism in placental morphology within mice with ASD-like phenotypes in term. The placental ASPG and DAD1 levels could reflect ASD-like symptom severity levels in male/female mice offspring.

5.
Sci Bull (Beijing) ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39155196

RESUMO

In medical image segmentation, it is often necessary to collect opinions from multiple experts to make the final decision. This clinical routine helps to mitigate individual bias. However, when data is annotated by multiple experts, standard deep learning models are often not applicable. In this paper, we propose a novel neural network framework called Multi-rater Prism (MrPrism) to learn medical image segmentation from multiple labels. Inspired by iterative half-quadratic optimization, MrPrism combines the task of assigning multi-rater confidences and calibrated segmentation in a recurrent manner. During this process, MrPrism learns inter-observer variability while taking into account the image's semantic properties and finally converges to a self-calibrated segmentation result reflecting inter-observer agreement. Specifically, we propose Converging Prism (ConP) and Diverging Prism (DivP) to iteratively process the two tasks. ConP learns calibrated segmentation based on multi-rater confidence maps estimated by DivP, and DivP generates multi-rater confidence maps based on segmentation masks estimated by ConP. Experimental results show that the two tasks can mutually improve each other through this recurrent process. The final converged segmentation result of MrPrism outperforms state-of-the-art (SOTA) methods for a wide range of medical image segmentation tasks. The code is available at https://github.com/WuJunde/MrPrism.

6.
ACS Catal ; 14(15): 11741-11748, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39114088

RESUMO

The impact of Sn on the concentration and strength of acid sites in Al containing zeolites with MFI topology and their catalytic activity for the dehydration of cyclohexanol in the aqueous phase has been investigated. The materials maintain constant Al concentrations and consequently BroÌ·nsted acid site (BAS) concentrations, while exhibiting an increasing concentration of Sn Lewis acid sites (LAS). The presence of water alters LAS(Sn), leading to weak BAS(Sn) that increases the concentration of water in the zeolite micropore, while leaving the rate of dehydration of cyclohexanol unchanged. The TOF increases with the concentration of BAS(Al) in close contact with framework LAS(Sn), referred to as BAS(Pair). The increase in the Arrhenius pre-exponential factor, without affecting the activation barrier (E a), leads to the hypothesis that the proximity of both sites allows for a later transition state induced by the polarization of the C-O bond, leading in turn to a higher transition entropy.

8.
J Evid Based Med ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107928

RESUMO

OBJECTIVE: This study aimed to develop and validate an eMCI-CHD tool based on clinical data to predict mild cognitive impairment (MCI) risk in patients with coronary heart disease (CHD). METHODS: This cross-sectional study prospectively collected data from 400 patients with coronary heart disease (aged 55-90 years, 62% men) from July 2022 to September 2023 and randomized (7:3 ratio) them into training and validation sets. After determining the modeling variables through least absolute shrinkage and selection operator regression analysis, four ML classifiers were developed: logistic regression, extreme gradient boosting (XGBoost), support vector machine, and random forest. The performance of the models was evaluated using area under the ROC curve, accuracy, sensitivity, specificity, and F1 score. Decision curve analysis was used to assess the clinical performance of the established models. The SHapley Additive exPlanations (SHAP) method was applied to determine the significance of the features, the predictive model was visualized with a nomogram, and an online web-based calculator for predicting CHD-MCI risk scores was developed. RESULTS: Of 400 CHD patients (average age 70.86 ± 8.74 years), 220 (55%) had MCI. The XGBoost model demonstrated superior performance (AUC: 0.86, accuracy: 78.57%, sensitivity: 0.74, specificity: 0.84, F1: 0.79) and underwent validation. An online tool (https://mr.cscps.com.cn/mci/index.html) with seven predictive variables (APOE gene typing, age, education, TyG index, NT-proBNP, C-reactive protein, and occupation) assessed MCI risk in CHD patients. CONCLUSION: This study highlights the potential for predicting MCI risk among CHD patients using an ML model-driven nomogram and risk scoring tool based on clinical data.

9.
Sci Rep ; 14(1): 18371, 2024 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112494

RESUMO

Ubiquitin-like with PHD and RING finger domains 1 (UHRF1) is an epigenetic regulator that plays critical roles in tumours. However, the DNA methylation alteration patterns driven by UHRF1 and the related differentially expressed tumour-related genes remain unclear. In this study, a UHRF1-shRNA MCF-7 cell line was constructed, and whole-genome bisulfite sequencing and RNA sequencing were performed. The DNA methylation alteration landscape was elucidated, and DNA methylation-altered regions (DMRs) were found to be distributed in both gene bodies and adjacent regions. The DMRs were annotated and categorized into 488 hypermethylated/1696 hypomethylated promoters and 1149 hypermethylated/5501 hypomethylated gene bodies. Through an integrated analysis with the RNA sequencing data, 217 methylation-regulated upregulated genes and 288 downregulated genes were identified, and these genes were primarily enriched in nervous system development and cancer signalling pathways. Further analysis revealed 21 downregulated oncogenes and 15 upregulated TSGs. We also showed that UHRF1 silencing inhibited cell proliferation and migration and suppressed tumour growth in vivo. Our study suggested that UHRF1 and the oncogenes or TSGs it regulates might serve as biomarkers and targets for breast cancer treatment.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Células MCF-7 , Feminino , Proliferação de Células/genética , Animais , Regiões Promotoras Genéticas , Camundongos , Epigênese Genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Movimento Celular/genética
10.
Curr Res Microb Sci ; 7: 100260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129758

RESUMO

HIV-1 envelope glycoprotein gp41 mediates fusion between HIV-1 and host cell membranes, making inhibitors of gp41 attractive anti-HIV drugs. We previously reported an efficient HIV-1 fusion inhibitor, ADS-J1, with a Y-shaped structure. Here, we discovered a new compound, ADS-J21, with a Y-shaped structure similar to that of ADS-J1 but with a lower molecular weight. Moreover, ADS-J21 exhibited effective anti-HIV-1 activity against divergent HIV-1 strains in vitro, including several HIV-1 laboratory-adapted strains and primary isolates with different subtypes (clades A to F) and tropisms (X4 or R5). Mechanistic studies have demonstrated that ADS-J21 blocks the formation of the gp41 six-helix bundle (6-HB) by targeting conserved amino acids Lys35 and Trp32. These findings suggest that ADS-J21 can be used as a new lead compound for further optimization in the development of a small-molecule fusion inhibitor.

11.
Food Chem ; 460(Pt 2): 140608, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39089031

RESUMO

This study explored the mechanism of interaction of pH-shifting combined ultrasonication and its effect on soybean lipophilic proteins (SLP) and the potential of modified SLP as the carrier for vitamin E (VE) and quercetin (QU). The spectroscopy results revealed that both VE and QU changed the SLP conformation and exposed hydrophobic groups. The loading rates of VE and QU by SLP with alkaline pH-shifting combined with ultrasonication (300 w,20 min) were 86.91% and 75.99%, respectively. According to the antioxidant analysis, with an increase in the ultrasonication power, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging capacity of the samples increased, where the DPPH and ABTS radical scavenging capacity of sample SQV-6 were 70.90% and 63.43%, respectively. The physicochemical properties, microstructure, and stability of the SLP-VE-QU complex improved significantly. Overall, the present findings broadened the application of simple structural carriers for co-encapsulating functional factors.

12.
Photodiagnosis Photodyn Ther ; : 104298, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089477

RESUMO

OBJECTIVE: To evaluate the efficacy of CO2 fractional laser and microneedling pretreatment combined with ALA-PDT for moderate-to-severe acne, aiming to optimize clinical treatment. METHODS: Patients were randomly divided into three groups: Group A (CO2 fractional laser + ALA-PDT), Group B (microneedling + ALA-PDT), and Group C (ALA-PDT). Each group underwent photodynamic therapy once a week for 3 weeks. Efficacy was assessed at the end of the 4th week, and recurrence was assessed at the end of the 12th week. RESULTS: A total of 150 patients with moderate to severe acne were included in this study, with 50 patients in each group. Four weeks after the end of treatment, the effective rates were 88% for Group A, 62% for Group B, and 36% for Group C. Statistically significant differences were found between the groups (P < 0.05), with Group A showing superior efficacy compared to Group B (P < 0.05). No serious systemic or local adverse reactions were observed in any group. No recurrence was seen in any group 12 weeks after the end of treatment, and some patients continued to show improvement in skin lesions over time. CONCLUSION: Both the CO2 fractional laser group and the microneedling group improved the efficacy of photodynamic therapy for moderate to severe acne compared to the control group, with the CO2 fractional laser group demonstrating better efficacy and fewer adverse effects.

13.
J Biol Chem ; : 107614, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089585

RESUMO

BACKGROUND: Ruminococcus gnavus is a mucolytic commensal bacterium whose increased gut colonization has been associated with chronic inflammatory and metabolic diseases in humans. Whether R. gnavus metabolites can modulate host intestinal physiology remains largely understudied. METHODS: We performed untargeted metabolomic and bulk RNA sequencing analyses using R. gnavus mono-colonization in germ free mice. Based on transcriptome-metabolome correlations, we tested the impact of specific arginine metabolites on intestinal epithelial production of nitric oxide (NO) and examined the effect of NO on the growth of various strains of R. gnavus in vitro and in Nos2-deficient mice. RESULTS: R. gnavus produces specific arginine, tryptophan and tyrosine metabolites, some of which are regulated by the environmental richness of sialic acid and mucin. R. gnavus colonization promotes expression of amino acid transporters and enzymes involved in metabolic flux of arginine and associated metabolites into NO. R. gnavus induced elevated levels of Nitric Oxide Synthase 2 (NOS2) while Nos2 ablation resulted in R. gnavus expansion in vivo. The growth of various R. gnavus strains can be inhibited by NO. Specific R. gnavus metabolites modulate intestinal epithelial cell NOS2 abundance and reduce epithelial barrier function at higher concentrations. CONCLUSIONS: Intestinal colonization and interaction with R. gnavus are partially regulated by an arginine-NO metabolic pathway, whereby a balanced control by the gut epithelium may restrain R. gnavus growth in healthy individuals. Disruption in this arginine metabolic regulation will contribute to the expansion and blooming of R. gnavus.

14.
Poult Sci ; 103(10): 104168, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39137498

RESUMO

This experiment aimed to investigate the in vitro antimicrobial activity of danofloxacin against Escherichia coli (E. coli) isolated from pigeons, as well as the pharmacokinetics of danofloxacin in pigeons following oral (PO), intramuscular (IM), and intravenous (IV) administration. The minimum inhibitory concentration (MIC) of danofloxacin was first determined for 38 clinical E. coli strains using the micro broth dilution method. Subsequently, 30 healthy pigeons were weighed and randomly divided into 3 groups: IM, IV, and PO, with 10 pigeons in each group. Danofloxacin was given at 5 mg/kg body weight (BW) through 3 different routes. Blood was collected, and plasma was separated at various time points from 0 to 48 h. Plasma samples were analyzed for danofloxacin concentrations using a validated HPLC method. Pharmacokinetic analysis was performed using Phoenix software and a noncompartmental analytical (NCA) method. The results indicated that danofloxacin had a strong antibacterial effect on E. coli, with a MIC50 of 0.5 µg/mL. The noncompartmental analysis showed that after PO and IM administration at 5 mg/kg in pigeons, peak plasma concentrations (Cmax) of 0.61 and 1.62 µg/mL were reached at 4.5 and 0.53 h, respectively. The oral and intramuscular bioavailability (F) were 68.08% ± 24.82% and 87.82% ± 25.36%, respectively. Following IV administration, danofloxacin was widely distributed in pigeons, with volume of distribution (VZ) and volume of distribution at steady state (VSS) values of 6.11 ± 2.01 and 4.65 ± 1.62 L/kg, respectively, and was eliminated slowly, with an elimination half-life (t1/2λz) of 6.41 ± 2.15 h. Based on the calculated ratio values of AUC/MIC, the current IV, IM, and PO doses of 5 mg/kg of danofloxacin would be expected to effectively treat pigeons infected with E. coli strains with MIC values equal to or less than 0.5 µg/mL.

15.
Animals (Basel) ; 14(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39123794

RESUMO

This study developed an individual-rearing method to compare the effects of live feed (sandworms Perinereis aibuhitensis), formulated pellet diets, and a mixture of live feed and formula feed on the Kuruma shrimp Penaeus japonicus, aiming to minimize the influence of non-dietary factors on the growth of P. japonicus, like cannibalism. Results indicated that live feed, with its higher protein, essential amino acids, and fatty acid content, led to significantly better growth and feeding performance in P. japonicus (p < 0.05) compared to pellet diets. A mixed diet resulted in a lower average daily protein intake yet maintained a growth and feeding performance comparable to live feed. The intestinal microbiota of shrimp, dominated by Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria, showed significant shifts with diet changes. Specifically, formulated feed increased the relative abundance of Vibrio and Photobacterium while decreasing Shimia and Rhodobacterales (p < 0.05), and feeding live food resulted in a more complex and stable bacterial network. Notably, individual variances in growth and feeding were observed among shrimps, with some on formulated diets showing growth comparable to those on live feed. Each shrimp's final weight, specific growth rate, protein efficiency rate, and average daily food intake positively correlated with its initial body weight (p < 0.05), and daily intake varied cyclically with the molting cycle. These findings suggest that individual-rearing is an effective approach for detailed feed evaluation and monitoring in P. japonicus, contributing to improved feed selection, development, and feeding strategies.

16.
Materials (Basel) ; 17(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39124457

RESUMO

The split-Hopkinson pressure bar technique is widely used to determine the dynamic mechanical behavior of materials. However, spike-like stress features appear in the initial stress behavior of ultra-soft materials tested with a split-Hopkinson bar. These features are not intrinsic characteristics of the materials. Potential causes were investigated through experiments and numerical simulations. It was found that the spike feature represents derived stress resulting from the radial inertia effect during dynamic loading. In this work, we propose and experimentally verify effective methods to reduce this effect. The influences of density, strain acceleration, ratio between inner and outer diameter, and Poisson's ratio on the radial inertia effect were investigated. The spike stress was found to change linearly with density and strain acceleration but decrease significantly when the inner/outer diameter ratio was below 0.3, after which it remained nearly constant. A parabolic stress distribution was observed along the radial direction due to the Poisson effect, especially when the ratio exceeded 0.3, leading to higher spike stress. Finally, suggestions were proposed as experimental guidance when testing ultra-soft materials.

17.
Mol Carcinog ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136583

RESUMO

Xenotropic and polytropic retrovirus receptor 1 (XPR1) is the only known transporter associated with Pi efflux in mammals, and its impact on tumor progression is gradually being revealed. However, the role of XPR1 in hepatocellular carcinoma (HCC) is unknown. A bioinformatics screen for the phosphate exporter XPR1 was performed in HCC patients. The expression of XPR1 in clinical specimens was analyzed using quantitative real-time PCR, Western blot analysis, and immunohistochemical assays. Knockdown of the phosphate exporter XPR1 was performed by shRNA transfection to investigate the cellular phenotype and phosphate-related cytotoxicity of the Huh7 and HLF cell lines. In vivo tests were conducted to investigate the tumorigenicity of HCC cells xenografted into immunocompromised mice after silencing XPR1. Compared with that in paracancerous tissue, XPR1 expression in HCC tissues was markedly upregulated. High XPR1 expression significantly correlated with poor patient survival. Silencing of XPR1 leads to decreased proliferation, migration, invasion, and colony formation in HCC cells. Mechanistically, knockdown of XPR1 causes an increase in intracellular phosphate levels; mitochondrial dysfunction characterized by reduced mitochondrial membrane potential and adenosine triphosphate levels; increased reactive oxygen species levels; abnormal mitochondrial morphology; and downregulation of key mitochondrial fusion, fission, and inner membrane genes. This ultimately results in mitochondria-dependent apoptosis. These findings reveal the prognostic value of XPR1 in HCC progression and, more importantly, suggest that XPR1 might be a potential therapeutic target.

18.
Nat Commun ; 15(1): 6497, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090084

RESUMO

Behavioral flexibility relies on the brain's ability to switch rapidly between multiple tasks, even when the task rule is not explicitly cued but must be inferred through trial and error. The underlying neural circuit mechanism remains poorly understood. We investigated recurrent neural networks (RNNs) trained to perform an analog of the classic Wisconsin Card Sorting Test. The networks consist of two modules responsible for rule representation and sensorimotor mapping, respectively, where each module is comprised of a circuit with excitatory neurons and three major types of inhibitory neurons. We found that rule representation by self-sustained persistent activity across trials, error monitoring and gated sensorimotor mapping emerged from training. Systematic dissection of trained RNNs revealed a detailed circuit mechanism that is consistent across networks trained with different hyperparameters. The networks' dynamical trajectories for different rules resided in separate subspaces of population activity; the subspaces collapsed and performance was reduced to chance level when dendrite-targeting somatostatin-expressing interneurons were silenced, illustrating how a phenomenological description of representational subspaces is explained by a specific circuit mechanism.


Assuntos
Modelos Neurológicos , Redes Neurais de Computação , Animais , Rede Nervosa/fisiologia , Neurônios/fisiologia , Interneurônios/fisiologia , Encéfalo/fisiologia , Humanos
19.
J Neuroimmunol ; 394: 578408, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39098102

RESUMO

Epstein-Barr virus (EBV) is deemed a necessary, yet insufficient factor in the development of multiple sclerosis (MS). In this study, myelin basic protein-specific transgenic T cell receptor mice were infected with murid gammaherpesvirus 68 virus (MHV68), an EBV-like virus that infects mice, resulting in the onset neurological deficits at a significantly higher frequency than influenza or mock-infected mice. MHV68 infected mice exhibited signs including optic neuritis and ataxia which are frequently observed in MS patients but not in experimental autoimmune encephalomyelitis mice. MHV68-infected mice exhibited increased focal immune cell infiltration in the central nervous system. Single cell RNA sequencing identified the emergence of a population of B cells that express genes associated with antigen presentation and costimulation, indicating that gammaherpesvirus infection drives a distinct, pro-inflammatory transcriptional program in B cells that may promote autoreactive T cell responses in MS.

20.
Cells ; 13(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39120264

RESUMO

Adipose tissue beiging refers to the process by which beige adipocytes emerge in classical white adipose tissue depots. Beige adipocytes dissipate chemical energy and secrete adipokines, such as classical brown adipocytes, to improve systemic metabolism, which is beneficial for people with obesity and metabolic diseases. Cold exposure and ß3-adrenergic receptor (AR) agonist treatment are two commonly used stimuli for increasing beige adipocytes in mice; however, their underlying biological processes are different. Transcriptional analysis of inguinal white adipose tissue (iWAT) has revealed that changes in extracellular matrix (ECM) pathway genes are specific to cold exposure. Hyaluronic acid (HA), a non-sulfated linear polysaccharide produced by nearly all cells, is one of the most common components of ECM. We found that cold exposure significantly increased iWAT HA levels, whereas the ß3-AR agonist CL316,243 did not. Increasing HA levels in iWAT by Has2 overexpression significantly increases cold-induced adipose tissue beiging; in contrast, decreasing HA by Spam1 overexpression, which encodes a hyaluronidase that digests HA, significantly decreases cold-induced iWAT beiging. All these data implicate a role of HA in promoting adipose tissue beiging, which is unique to cold exposure. Given the failure of ß3-AR agonists in clinical trials for obesity and metabolic diseases, increasing HA could serve as a new approach for recruiting more beige adipocytes to combat metabolic diseases.


Assuntos
Tecido Adiposo Branco , Temperatura Baixa , Ácido Hialurônico , Ácido Hialurônico/metabolismo , Animais , Camundongos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Masculino , Tecido Adiposo Bege/metabolismo , Adipócitos Bege/metabolismo , Adipócitos Bege/efeitos dos fármacos , Matriz Extracelular/metabolismo , Dioxóis/farmacologia , Receptores Adrenérgicos beta 3/metabolismo , Agonistas de Receptores Adrenérgicos beta 3/farmacologia
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