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1.
Natl Sci Rev ; 11(10): nwae296, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39315280

RESUMO

Cold-adapted species are able to generate cryoprotective proteins and glycoproteins to prevent freezing damage. The [→4)-ß-D-Manp-(1→4)-ß-D-Xylp-(1→] n xylomannan from the Alaska beetle Upis ceramboides was disclosed by Walters and co-workers in 2009 as the first glycan-based antifreeze agent, which was later reported to be found in diverse taxa. Here, we report the rapid synthesis of four types of xylomannans, including the proposed antifreeze xylomannan up to a 64-mer (Type I), the regioisomeric [→3)-ß-D-Manp-(1→4)-ß-D-Xylp-(1→] n 16-mer (Type II), the diastereomeric [→4)-ß-L-Manp-(1→4)-ß-D-Xylp-(1→] n 16-mer (Type III) and the block-wise [→4)-ß-D-Manp-(1→] m [→4)-ß-D-Xylp-(1→] n 32-mer (Type IV), by employing a strategic iterative exponential glycan growth (IEGG) process. The nuclear magnetic resonance spectral data of the alleged natural xylomannan are in accordance only to those of the block-wise Type IV glycan and none of these synthetic xylomannans has been found to be capable of inducing thermal hysteresis. These results disprove the previous reports about the natural occurrence of antifreeze xylomannans.

2.
J Am Chem Soc ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39314057

RESUMO

A diarylurea-containing phosphine ligand-modulated stereoinvertive O-glycosylation with primal furanosyl and pyranosyl ortho-alkynylbenzoate (ABz) donors under gold(I) catalysis is disclosed. Both α- and ß-configured glycosides could be obtained from the corresponding stereochemically pure ß- and α-glycosyl donors with high yields and good to excellent stereoselectivities, respectively. This method accommodates a variety of glycosyl donors and alcoholic acceptors, leading to both 1,2-cis and 1,2-trans glycosidic linkages, and has been applied to the convenient preparation of a series of linear arabinan glycans. Mechanistic investigations reveal that the counteranion could bridge the diarylurea residue on the phosphine ligand with the alcoholic acceptor via hydrogen bond interactions, thereby permitting stereoinvertive displacement at the anomeric position.

3.
Proc Natl Acad Sci U S A ; 121(37): e2402817121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39236246

RESUMO

Autophagy of glycogen (glycophagy) is crucial for the maintenance of cellular glucose homeostasis and physiology in mammals. STBD1 can serve as an autophagy receptor to mediate glycophagy by specifically recognizing glycogen and relevant key autophagic factors, but with poorly understood mechanisms. Here, we systematically characterize the interactions of STBD1 with glycogen and related saccharides, and determine the crystal structure of the STBD1 CBM20 domain with maltotetraose, uncovering a unique binding mode involving two different oligosaccharide-binding sites adopted by STBD1 CBM20 for recognizing glycogen. In addition, we demonstrate that the LC3-interacting region (LIR) motif of STBD1 can selectively bind to six mammalian ATG8 family members. We elucidate the detailed molecular mechanism underlying the selective interactions of STBD1 with ATG8 family proteins by solving the STBD1 LIR/GABARAPL1 complex structure. Importantly, our cell-based assays reveal that both the STBD1 LIR/GABARAPL1 interaction and the intact two oligosaccharide binding sites of STBD1 CBM20 are essential for the effective association of STBD1, GABARAPL1, and glycogen in cells. Finally, through mass spectrometry, biochemical, and structural modeling analyses, we unveil that STBD1 can directly bind to the Claw domain of RB1CC1 through its LIR, thereby recruiting the key autophagy initiation factor RB1CC1. In all, our findings provide mechanistic insights into the recognitions of glycogen, ATG8 family proteins, and RB1CC1 by STBD1 and shed light on the potential working mechanism of STBD1-mediated glycophagy.


Assuntos
Família da Proteína 8 Relacionada à Autofagia , Autofagia , Glicogênio , Animais , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Autofagia/fisiologia , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Família da Proteína 8 Relacionada à Autofagia/genética , Família da Proteína 8 Relacionada à Autofagia/química , Sítios de Ligação , Cristalografia por Raios X , Glicogênio/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/genética , Modelos Moleculares , Ligação Proteica
4.
Research (Wash D C) ; 7: 0468, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39238846

RESUMO

Intermittent fasting (IF) is a convenient dietary intervention for multiple diseases, including type 2 diabetes. However, whether it can be used as a long-term antidiabetic approach is still unknown. Here, we confirm that IF alone is beneficial for both moderate and severe diabetic mice, but its antidiabetic effects clearly diminish at later stages, especially for severe diabetic db/db mice, which have obviously impaired autophagy. We found that static magnetic fields can directly promote actin assembly and boost IF-induced autophagy. Consequently, the pancreatic islet and liver were improved, and the antidiabetic effects of IF were boosted. In fact, at later stages, combined static magnetic field and IF could reduce the blood glucose level of moderate type 2 diabetic mice by 40.5% (P < 0.001) and severe type 2 diabetes by 34.4% (P < 0.05), when IF alone no longer has significant blood glucose reduction effects. Therefore, although IF is generally beneficial for diabetes, our data reveal its insufficiency for late-stage diabetes, which can be compensated by a simple, noninvasive, long-lasting, and nonpharmacological strategy for effective long-term diabetic control.

5.
Int J Biol Sci ; 20(12): 4713-4730, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309425

RESUMO

Extensive loss of alveolar epithelial cells (AECs) undergoing necroptosis is a crucial mechanism of acute lung injury (ALI), but its triggering mechanism needs to be thoroughly investigated. Neutrophil extracellular traps (NETs) play a significant role in ALI. However, the effect of NETs on AECs' death has not been clarified. Our study found that intratracheal instillation of NETs disrupted lung tissue structure, suggesting that NETs could induce ALI in mice. Moreover, we observed that NETs could trigger necroptosis of AECs in vivo and in vitro. The phosphorylation levels of RIPK3 and MLKL were increased in MLE12 cells after NETs treatment (P < 0.05). Mechanistically, NETs taken up by AECs through endocytosis activated the cGAS-STING pathway and triggered AECs necroptosis. The expression of cGAS, STING, TBK1 and IRF3 were increased in MLE12 cells treated with NETs (P < 0.05). Furthermore, the cGAS inhibitor RU.521 inhibited NETs-triggered AECs necroptosis and alleviated the pulmonary damage induced by NETs in mice. In conclusion, our study demonstrates that NETs taken up by AECs via endocytosis can activate the cGAS-STING pathway and trigger AECs necroptosis to promote ALI in mice. Our findings indicate that targeting the NETs/cGAS-STING/necroptosis pathway in AECs is an effective strategy for treating ALI.


Assuntos
Lesão Pulmonar Aguda , Células Epiteliais Alveolares , Armadilhas Extracelulares , Proteínas de Membrana , Necroptose , Nucleotidiltransferases , Animais , Armadilhas Extracelulares/metabolismo , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Camundongos , Nucleotidiltransferases/metabolismo , Células Epiteliais Alveolares/metabolismo , Proteínas de Membrana/metabolismo , Masculino , Transdução de Sinais , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
6.
J Inflamm Res ; 17: 6415-6437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39310902

RESUMO

Purpose: Psoriasis is not yet completely curable, and its etiology and pathogenesis are unclear. Necroptosis, also known as programmed necrosis, is a regulated mode of necrotic cell death. The interaction between inflammatory diseases and necrotic apoptosis has recently attracted significant attention. We explored the molecular mechanisms of necrotic apoptosis-related genes in psoriasis using bioinformatics methods to identify potential biomarkers for psoriasis. Patients and Methods: In this study, we screened psoriasis differentially expressed genes from the datasets GSE13355 and GSE14905 and took intersections with necrotic apoptosis-related genes for the next analysis. We used multiple machine learning algorithms to screen key genes and perform enrichment analysis. In addition, we performed an immune infiltration analysis. Transcription factors were predicted by the R package "RcisTarget". We also observed the cellular clustering of key genes in different cell types at the single-cell sequencing level. We used real-time fluorescence-based quantitative-polymerase chain reaction, Western blot, and immunohistochemistry to analyze gene expression in clinical samples. We constructed an imiquimod-induced psoriasis-like dermatitis model in mice for further validation. Results: Seven key genes were screened as follows: AIM2, CARD6, HPSE, MYD88, PYCARD, RAI14, and TNFSF10. Enrichment analysis showed that the key genes were mainly involved in inflammatory pathways. Immune infiltration analysis showed significantly higher levels of CD8 T cells, CD4 initial T cells, and CD4 memory-activated T cells in the disease group's samples than in the normal patients' samples. The key gene expression in single cells analyzed showed that PYCARD was significantly expressed in keratinocytes. PYCARD was selected for gene expression analysis; the results showed that its expression was significantly elevated in the skin lesion tissues of patients with psoriasis. We also verified that PYCARD might play a vital role in the development of psoriasis skin lesions using animal experiments. Conclusion: PYCARD plays a vital role in psoriasis development and is a potential biomarker for psoriasis.

7.
Circ Cardiovasc Imaging ; 17(9): e016842, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39268602

RESUMO

BACKGROUND: Intraindividual variability in lipid profiles is recognized as a potential predictor of cardiovascular events. However, the influence of early adulthood lipid profile variability along with mean lipid levels on future coronary artery calcium (CAC) incidence remains unclear. METHODS: A total of 2395 participants (41.6% men; mean±SD age, 40.2±3.6 years) with initial CAC =0 from the CARDIA study (Coronary Artery Risk Development in Young Adults) were included. Serial lipid measurements were obtained to calculate mean levels and variability of total cholesterol, low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and triglycerides. CAC incidence was defined as CAC >0 at follow-up. RESULTS: During a mean follow-up of 9.0 years, 534 individuals (22.3%) exhibited CAC incidence. Higher mean levels of total cholesterol, LDL-C, and non-HDL-C were associated with a greater risk of future CAC incidence. Similarly, 1-SD increment of lipid variability, as assessed by variability independent of the mean, was associated with an increased risk of CAC incidence (LDL-C: hazard ratio, 1.139 [95% CI, 1.048-1.238]; P=0.002; non-HDL-C: hazard ratio, 1.102 [95% CI, 1.014-1.198]; P=0.022; and triglycerides: hazard ratio, 1.480 [95% CI, 1.384-1.582]; P<0.001). Combination analyses demonstrated that participants with both high lipid levels and high variability in lipid profiles (LDL-C and non-HDL-C) faced the greatest risk of CAC incidence. Specifically, elevated variability of LDL-C was associated with an additional risk of CAC incidence even in low mean levels of LDL-C (hazard ratio, 1.396 [95% CI, 1.106-1.763]; P=0.005). These findings remained robust across a series of sensitivity and subgroup analyses. CONCLUSIONS: Elevated variability in LDL-C and non-HDL-C during young adulthood was associated with an increased risk of CAC incidence in midlife, especially among those with high mean levels of atherogenic lipoproteins. These findings highlight the importance of maintaining consistently low levels of atherogenic lipids throughout early adulthood to reduce subclinical atherosclerosis in midlife. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00005130.


Assuntos
Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Masculino , Feminino , Incidência , Adulto , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/sangue , Medição de Risco/métodos , Fatores de Risco , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Biomarcadores/sangue , Lipídeos/sangue , Adulto Jovem , Estudos Prospectivos , Fatores Etários , Triglicerídeos/sangue , LDL-Colesterol/sangue , Fatores de Tempo , Angiografia Coronária/métodos
8.
Diabetes Care ; 47(10): 1818-1825, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39137135

RESUMO

OBJECTIVE: The impact of comprehensive risk factor control on heart failure (HF) risk and HF-free survival time in individuals with type 2 diabetes (T2D) was evaluated in this study. RESEARCH DESIGN AND METHODS: This prospective study included 11,949 individuals diagnosed with T2D, matched with 47,796 non-T2D control study participants from the UK Biobank cohort. The degree of comprehensive risk factor control was assessed on the basis of the major cardiovascular risk factors, including blood pressure, BMI, LDL cholesterol, hemoglobin A1c, renal function, smoking, diet, and physical activity. Cox proportional hazards models were used to measure the associations between the degree of risk factor control and HF risk. Irwin's restricted mean was used to evaluate HF-free survival time. RESULTS: During a median follow-up of 12.3 years, 702 individuals (5.87%) with T2D and 1,402 matched control participants (2.93%) developed HF. Each additional risk factor controlled was associated with an average 19% lower risk of HF. Optimal control of at least six risk factors was associated with a 67% lower HF risk (hazard ratio [HR] 0.33; 95% CI 0.20, 0.54). BMI was the primary attributable risk factor for HF. Notably, the excess risk of HF associated with T2D could be attenuated to levels comparable to those of non-T2D control participants when individuals had a high degree of risk factor control (HR 0.66; 95% CI 0.40, 1.07), and they exhibited a longer HF-free survival time. CONCLUSIONS: Comprehensive management of risk factors is inversely associated with HF risk, and optimal risk factor control may prolong HF-free survival time among individuals with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Insuficiência Cardíaca/epidemiologia , Estudos Prospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Idoso , Adulto
9.
Angew Chem Int Ed Engl ; : e202412436, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39206505

RESUMO

The selective functionalization of carbohydrates holds a central position in synthetic carbohydrate chemistry, driving the ongoing quest for ideal approaches to manipulate these compounds. In this study, we introduce a general strategy that enables the regiodivergent functionalization of saccharides. The use of electron-deficient photoactive 4-tetrafluoropyridinylthio (SPyf) fragment as an adaptable activating group, facilitated efficient functionalization across all saccharide sites. More importantly, this activating group can be directly installed at the C1, C5 and C6 positions of biomass-derived carbohydrates in a single step and in a site-selective manner, allowing for the efficient and precision-oriented modification of unprotected saccharides and glycans.

10.
Nutrients ; 16(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39203827

RESUMO

Research on dietary fatty acids (FAs) and lung health has reported skeptical findings. This study aims to examine the causal relationship between circulating FAs and Chronic Obstructive Pulmonary Disease (COPD) onset and exacerbation, using a two-sample Mendelian Randomization (MR) analysis. Strong and independent genetic variants of FAs were obtained from the UK Biobank of European ancestry. The exposure traits included saturated FA (SFA), poly- and mono-unsaturated FA (PUFA and MUFA), omega-3 and omega-6 PUFA, docosahexaenoic acid (DHA), and linoleic acid (LA), all expressed as total FA (TFA) percentages. Summary statistics for COPD outcomes were obtained from the FinnGen consortium including COPD, COPD hospitalization, COPD/asthma-related infections, COPD-related respiratory insufficiency, and COPD/asthma/interstitial lung disease (ILD)-related pneumonia. The inverse-variance weighted (IVW) was the primary MR approach. MR-Egger regression and MR-PRESSO were utilized to evaluate heterogeneity and pleiotropy. MR-PRESSO tests suggested no obvious horizontal pleiotropy. MR results by the IVW approach indicated that the genetically high SFA/TFA levels were associated with an increased risk of COPD/asthma/ILD-related pneumonia (OR: 1.275, 95%CI: 1.103-1.474, p for FDR = 0.002). No significant relationship was observed between other types of FAs and COPD outcomes. Our MR analysis suggests that there is weak evidence that the genetically predicted high SFA/TFA was associated with an increased risk of pneumonia.


Assuntos
Ácidos Graxos Insaturados , Análise da Randomização Mendeliana , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Ácidos Graxos Insaturados/sangue , Ácidos Graxos/sangue , Asma/genética , Asma/sangue , Asma/epidemiologia , Fatores de Risco , Polimorfismo de Nucleotídeo Único , Feminino , Masculino , Ácidos Graxos Ômega-3/sangue
11.
Adv Sci (Weinh) ; : e2307254, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946659

RESUMO

The rational construction of efficient hypoxia-tolerant nanocatalysts capable of generating singlet oxygen (1O2) without external stimuli is of great importance for tumor therapy. Herein, uniformly dispersed and favorable biosafety profile graphitic carbon nitride quantum dots immobilized with Fe-N4 moieties modulated by axial O atom (denoted as O-Fe-N4) are developed for converting H2O2 into 1O2 via Russell reaction, without introducing external energy. Notably, O-Fe-N4 performs two interconnected catalytic properties: glutathione oxidase-mimic activity to provide substrate for subsequent 1O2 generation, avoiding the blunting anticancer efficacy by glutathione. The O-Fe-N4 catalyst demonstrates a specific activity of 79.58 U mg-1 at pH 6.2, outperforming the most reported Fe-N4 catalysts. Density functional theory calculations demonstrate that the axial O atom can effectively modulate the relative position and electron affinity between Fe and N, lowering the activation energy, strengthening the selectivity, and thus facilitating the Russell-type reaction. The gratifying enzymatic activity stemming from the well-defined Fe-N/O structure can inhibit tumor proliferation by efficiently downregulating glutathione peroxidase 4 activity and inducing lipid peroxidation. Altogether, the O-Fe-N4 catalyst not only represents an efficient platform for self-cascaded catalysis to address the limitations of 1O2-involved cancer treatment but also provides a paradigm to enhance the performance of the Fe-N4 catalyst.

12.
Mater Today Bio ; 27: 101137, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39040221

RESUMO

The translation of Fe-based agents for ferroptosis tumor therapy is restricted by the unstable iron valence state, the harsh catalytic environment, and the complex tumor self-protection mechanism. Herein, we developed a stable nickel-based single-atom-metal-clusters (NSAMCs) biocatalyst for efficient tumor ferroptosis therapy. NSAMCs with a nanowire-like nanostructure and hydrophilic functional groups exhibit good water-solubility, colloidal stability, negligible systemic toxicity, and target specificity. In particular, NSAMCs possess excellent peroxidase-like and glutathione oxidase-like activities through the synergistic influence between metal clusters and single atoms. The dual-enzymatic performance enables NSAMCs to synergistically promote efficient ferroptosis of cancer cells through lipid peroxidization aggregation and glutathione peroxidase 4 inactivation. Importantly, NSAMCs highlight the boost of ferroptosis tumor therapy via the synergistic effect between single-atoms and metal clusters, providing a practical and feasible paradigm for further improving the efficiency of ferroptosis tumor treatment.

13.
Zool Res ; 45(4): 924-936, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021081

RESUMO

Amyloid beta (Aß) monomers aggregate to form fibrils and amyloid plaques, which are critical mechanisms in the pathogenesis of Alzheimer's disease (AD). Given the important role of Aß1-42 aggregation in plaque formation, leading to brain lesions and cognitive impairment, numerous studies have aimed to reduce Aß aggregation and slow AD progression. The diphenylalanine (FF) sequence is critical for amyloid aggregation, and magnetic fields can affect peptide alignment due to the diamagnetic anisotropy of aromatic rings. In this study, we examined the effects of a moderate-intensity rotating magnetic field (RMF) on Aß aggregation and AD pathogenesis. Results indicated that the RMF directly inhibited Aß amyloid fibril formation and reduced Aß-induced cytotoxicity in neural cells in vitro. Using the AD mouse model APP/PS1, RMF restored motor abilities to healthy control levels and significantly alleviated cognitive impairments, including exploration and spatial and non-spatial memory abilities. Tissue examinations demonstrated that RMF reduced amyloid plaque accumulation, attenuated microglial activation, and reduced oxidative stress in the APP/PS1 mouse brain. These findings suggest that RMF holds considerable potential as a non-invasive, high-penetration physical approach for AD treatment.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Disfunção Cognitiva , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Camundongos , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Campos Magnéticos , Modelos Animais de Doenças , Placa Amiloide , Encéfalo/metabolismo
14.
Nat Prod Rep ; 41(9): 1403-1440, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888170

RESUMO

Covering: 1987 to 2023Naturally existing glycoproteins through post-translational protein glycosylation are highly heterogeneous, which not only impedes the structure-function studies, but also hinders the development of their potential medical usage. Chemical synthesis represents one of the most powerful tools to provide the structurally well-defined glycoforms. Being the key step of glycoprotein synthesis, glycosylation usually takes place at serine, threonine, and asparagine residues, leading to the predominant formation of the O- and N-glycans, respectively. However, other amino acid residues containing oxygen, nitrogen, sulfur, and nucleophilic carbon atoms have also been found to be glycosylated. These diverse glycoprotein linkages, occurring from microorganisms to plants and animals, play also pivotal biological roles, such as in cell-cell recognition and communication. The availability of these homogenous rare glycopeptides and glycoproteins can help decipher the glyco-code for developing therapeutic agents. This review highlights the chemical approaches for assembly of the functional glycopeptides and glycoproteins bearing these "rare" carbohydrate-amino acid linkages between saccharide and canonical amino acid residues and their derivatives.


Assuntos
Aminoácidos , Glicopeptídeos , Glicoproteínas , Glicoproteínas/síntese química , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicopeptídeos/síntese química , Glicopeptídeos/química , Glicosilação , Aminoácidos/química , Aminoácidos/síntese química , Animais
15.
Mol Med ; 30(1): 93, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898476

RESUMO

BACKGROUND: The epithelial-mesenchymal transition (EMT) of human bronchial epithelial cells (HBECs) is essential for airway remodeling during asthma. Wnt5a has been implicated in various lung diseases, while its role in the EMT of HBECs during asthma is yet to be determined. This study sought to define whether Wnt5a initiated EMT, leading to airway remodeling through the induction of autophagy in HBECs. METHODS: Microarray analysis was used to investigate the expression change of WNT5A in asthma patients. In parallel, EMT models were induced using 16HBE cells by exposing them to house dust mites (HDM) or interleukin-4 (IL-4), and then the expression of Wnt5a was observed. Using in vitro gain- and loss-of-function approaches via Wnt5a mimic peptide FOXY5 and Wnt5a inhibitor BOX5, the alterations in the expression of the epithelial marker E-cadherin and the mesenchymal marker protein were observed. Mechanistically, the Ca2+/CaMKII signaling pathway and autophagy were evaluated. An autophagy inhibitor 3-MA was used to examine Wnt5a in the regulation of autophagy during EMT. Furthermore, we used a CaMKII inhibitor KN-93 to determine whether Wnt5a induced autophagy overactivation and EMT via the Ca2+/CaMKII signaling pathway. RESULTS: Asthma patients exhibited a significant increase in the gene expression of WNT5A compared to the healthy control. Upon HDM and IL-4 treatments, we observed that Wnt5a gene and protein expression levels were significantly increased in 16HBE cells. Interestingly, Wnt5a mimic peptide FOXY5 significantly inhibited E-cadherin and upregulated α-SMA, Collagen I, and autophagy marker proteins (Beclin1 and LC3-II). Rhodamine-phalloidin staining showed that FOXY5 resulted in a rearrangement of the cytoskeleton and an increase in the quantity of stress fibers in 16HBE cells. Importantly, blocking Wnt5a with BOX5 significantly inhibited autophagy and EMT induced by IL-4 in 16HBE cells. Mechanistically, autophagy inhibitor 3-MA and CaMKII inhibitor KN-93 reduced the EMT of 16HBE cells caused by FOXY5, as well as the increase in stress fibers, cell adhesion, and autophagy. CONCLUSION: This study illustrates a new link in the Wnt5a-Ca2+/CaMKII-autophagy axis to triggering airway remodeling. Our findings may provide novel strategies for the treatment of EMT-related diseases.


Assuntos
Asma , Autofagia , Células Epiteliais , Transição Epitelial-Mesenquimal , Proteína Wnt-5a , Humanos , Proteína Wnt-5a/metabolismo , Proteína Wnt-5a/genética , Asma/metabolismo , Asma/patologia , Asma/genética , Células Epiteliais/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Brônquios/metabolismo , Brônquios/patologia , Masculino , Linhagem Celular , Feminino , Pessoa de Meia-Idade , Transdução de Sinais , Adulto
16.
Eur Radiol ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844619

RESUMO

OBJECTIVES: Despite some existing studies on the safety of high static magnetic fields (SMFs), the effects of ultra-high SMFs above 20.0 T for embryonic development in early pregnancy are absent. The objective of this study is to evaluate the influence of 16.8-22.0 T SMF on the development of zebrafish embryos, which will provide important information for the future application of ultra-high field magnetic resonance imaging (MRI). METHODS: Two-hour exposure to homogenous (0 T/m) 22.0 T SMF, or 16.8 T SMFs with 123.25 T/m spatial gradient of opposite magnetic force directions was examined in the embryonic development of 200 zebrafish. Their body length, heart rate, spontaneous tail-wagging movement, hatching and survival rate, photomotor response, and visual motor response (VMR) were analyzed. RESULTS: Our results show that these ultra-high SMFs did not significantly affect the general development of zebrafish embryos, such as the body length or spontaneous tail-wagging movement. However, the hatching rate was reduced by the gradient SMFs (p < 0.05), but not the homogenous 22.0 T SMF. Moreover, although the zebrafish larva activities were differentially affected by these ultra-high SMFs (p < 0.05), the expression of several visual and neurodevelopmental genes (p < 0.05) was generally downregulated in the eyeball. CONCLUSIONS: Our findings suggest that exposure to ultra-high SMFs, especially the gradient SMFs, may have adverse effects on embryonic development, which should cause some attention to the future application of ultra-high field MRIs. CLINICAL RELEVANCE STATEMENT: As technology advances, it is conceivable that very strong magnetic fields may be adapted for use in medical imaging. Possible dangers associated with these higher Tesla fields need to be considered and evaluated prior to human use. KEY POINTS: Ultra-High static magnetic field may affect early embryonic development. High strength gradient static magnetic field exposure impacted zebrafish embryonic development. The application of very strong magnetic fields for MR technologies needs to be carefully evaluated.

17.
J Cosmet Dermatol ; 23(9): 2918-2926, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38712728

RESUMO

BACKGROUND: Papulopustular rosacea (PPR) is a chronic inflammatory disease with a significant impact on facial aesthetics. An impaired skin barrier is an important factor in the development and exacerbation of PPR. Tranexamic acid (TXA) has immune regulatory and anti-inflammatory effects, inhibits angiogenesis and endothelial hyperplasia, and promotes skin barrier repair. AIMS: We investigated the efficacy and safety of oral TXA for PPR treatment. PATIENTS/METHODS: In total, 70 patients were randomly assigned to receive traditional therapy plus oral TXA or traditional therapy alone for 8 weeks, with a 4-week follow-up period. The subjective improvement in rosacea was assessed using the clinical erythema assessment (CEA), investigator's global assessment (IGA), patient self-assessment (PSA) score, rosacea-specific quality of life (RQoL) score, and global aesthetic improvement score (GAIS). An objective improvement in rosacea was assessed using skin hydration, trans-epidermal water loss (TEWL), clinical photography, and an eight spectrum facial imager. RESULTS: CEA/IGA/PSA, dryness, and RQoL scores were significantly lower and GAIS was higher in the TXA group than in the traditional therapy group. Furthermore, oral TXA significantly improved skin barrier function, increased skin hydration, and decreased TEWL, with no significant side effects. Notably, we observed better outcomes and a greater improvement in skin barrier function with TXA treatment in patients with dry-type rosacea than in patients with oily skin. CONCLUSIONS: The addition of oral TXA to traditional therapy can lead to rapid and effective improvements in PPR, which may be attributed to improvements in skin barrier function.


Assuntos
Qualidade de Vida , Rosácea , Ácido Tranexâmico , Humanos , Rosácea/tratamento farmacológico , Ácido Tranexâmico/administração & dosagem , Feminino , Pessoa de Meia-Idade , Adulto , Administração Oral , Masculino , Resultado do Tratamento , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/uso terapêutico , Perda Insensível de Água/efeitos dos fármacos , Pele/efeitos dos fármacos , Índice de Gravidade de Doença , Face , Eritema/tratamento farmacológico , Eritema/etiologia
18.
Front Microbiol ; 15: 1332105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800758

RESUMO

Introduction: Research on the mechanism of marine polysaccharide utilization by Bacteroides thetaiotaomicron has drawn substantial attention in recent years. Derived from marine algae, the marine algae polysaccharides could serve as prebiotics to facilitate intestinal microecological balance and alleviate colonic diseases. Bacteroides thetaiotaomicron, considered the most efficient degrader of polysaccharides, relates to its capacity to degrade an extensive spectrum of complex polysaccharides. Polysaccharide utilization loci (PULs), a specialized organization of a collection of genes-encoded enzymes engaged in the breakdown and utilization of polysaccharides, make it possible for Bacteroides thetaiotaomicron to metabolize various polysaccharides. However, there is still a paucity of comprehensive studies on the procedure of polysaccharide degradation by Bacteroides thetaiotaomicron. Methods: In the current study, the degradation of four kinds of marine algae polysaccharides, including sodium alginate, fucoidan, laminarin, and Pyropia haitanensis polysaccharides, and the underlying mechanism by Bacteroides thetaiotaomicron G4 were investigated. Pure culture of Bacteroides thetaiotaomicron G4 in a substrate supplemented with these polysaccharides were performed. The change of OD600, total carbohydrate contents, and molecular weight during this fermentation were determined. Genomic sequencing and bioinformatic analysis were further performed to elucidate the mechanisms involved. Specifically, Gene Ontology (GO) annotation, Clusters of Orthologous Groups (COG) annotation, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were utilized to identify potential target genes and pathways. Results: Underlying target genes and pathways were recognized by employing bioinformatic analysis. Several PULs were found that are anticipated to participate in the breakdown of these four polysaccharides. These findings may help to understand the interactions between these marine seaweed polysaccharides and gut microorganisms. Discussion: The elucidation of polysaccharide degradation mechanisms by Bacteroides thetaiotaomicron provides valuable insights into the utilization of marine polysaccharides as prebiotics and their potential impact on gut health. Further studies are warranted to explore the specific roles of individual PULs and their contributions to polysaccharide metabolism in the gut microbiota.

19.
Org Biomol Chem ; 22(19): 3986-3994, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695061

RESUMO

Algae-based marine carbohydrate drugs are typically decorated with negative ion groups such as carboxylate and sulfate groups. However, the precise synthesis of highly sulfated alginates is challenging, thus impeding their structure-activity relationship studies. Herein we achieve a microwave-assisted synthesis of a range of highly sulfated mannuronate glycans with up to 17 sulfation sites by overcoming the incomplete sulfation due to the electrostatic repulsion of crowded polyanionic groups. Although the partially sulfated tetrasaccharide had the highest affinity for the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, the fully sulfated octasaccharide showed the most potent interference with the binding of the RBD to angiotensin-converting enzyme 2 (ACE2) and Vero E6 cells, indicating that the sulfated oligosaccharides might inhibit the RBD binding to ACE2 in a length-dependent manner.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , Micro-Ondas , Polissacarídeos , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Chlorocebus aethiops , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/química , Células Vero , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/síntese química , Humanos , Animais , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/síntese química , Sulfatos/química , Sulfatos/farmacologia , Sulfatos/síntese química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-Atividade
20.
Zool Res ; 45(3): 478-491, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38682430

RESUMO

Acetaminophen (APAP), the most frequently used mild analgesic and antipyretic drug worldwide, is implicated in causing 46% of all acute liver failures in the USA and between 40% and 70% in Europe. The predominant pharmacological intervention approved for mitigating such overdose is the antioxidant N-acetylcysteine (NAC); however, its efficacy is limited in cases of advanced liver injury or when administered at a late stage. In the current study, we discovered that treatment with a moderate intensity static magnetic field (SMF) notably reduced the mortality rate in mice subjected to high-dose APAP from 40% to 0%, proving effective at both the initial liver injury stage and the subsequent recovery stage. During the early phase of liver injury, SMF markedly reduced APAP-induced oxidative stress, free radicals, and liver damage, resulting in a reduction in multiple oxidative stress markers and an increase in the antioxidant glutathione (GSH). During the later stage of liver recovery, application of vertically downward SMF increased DNA synthesis and hepatocyte proliferation. Moreover, the combination of NAC and SMF significantly mitigated liver damage induced by high-dose APAP and increased liver recovery, even 24 h post overdose, when the effectiveness of NAC alone substantially declines. Overall, this study provides a non-invasive non-pharmaceutical tool that offers dual benefits in the injury and repair stages following APAP overdose. Of note, this tool can work as an alternative to or in combination with NAC to prevent or minimize liver damage induced by APAP, and potentially other toxic overdoses.


Assuntos
Acetaminofen , Analgésicos não Narcóticos , Doença Hepática Induzida por Substâncias e Drogas , Overdose de Drogas , Acetaminofen/toxicidade , Animais , Camundongos , Analgésicos não Narcóticos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Masculino , Campos Magnéticos , Acetilcisteína/uso terapêutico , Acetilcisteína/farmacologia
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