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1.
World J Gastrointest Surg ; 16(9): 2769-2773, 2024 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-39351571

RÉSUMÉ

This editorial discusses the article written by Tchilikidi et al that was published in the latest edition of the World Journal of Gastrointestinal Surgery. Genetic and molecular profiling of perihilar cholangiocarcinoma (pCCA) has identified a number of key abnormalities that drive tumor growth and spread, including pyruvate kinase M2, proline rich 11, and transcription factor 7, etc. pCCA has specific genetic and molecular features that can be used to develop personalized treatment plans. Personalized treatment approaches offer new opportunities for effectively targeting the underlying drivers of tumor growth and progression. The findings based on tumor genetic and molecular characteristics highlight the importance of developing personalized treatment strategies.

2.
Pest Manag Sci ; 2024 Oct 07.
Article de Anglais | MEDLINE | ID: mdl-39373165

RÉSUMÉ

BACKGROUND: Bacterial biofilm is a strong fortress for bacteria to resist harsh external environments, which can enhance their tolerance and exacerbate the drug/pesticide resistance risk. Currently, photopharmacology provides an advanced approach via precise spatiotemporal control for regulating biological activities by light-controlling the molecular configurations, thereby having enormous potential in the development of drug/pesticides. RESULTS: To further expand the photopharmacology application for discovering new antibiofilm agents, we prepared a series of light-controlled azo-active molecules and explored their photo isomerization, fatigue resistance, and anti-biofilm performance. Furthermore, their mechanisms of inhibiting biofilm formation were systematically investigated. Overall, designed azo-derivative A11 featured excellent anti-Xoo activity with an half-maximal effective concentration (EC50) value of 5.45 µg mL-1, and the EC50 value could be further elevated to 2.19 µg mL-1 after ultraviolet irradiation (converted as cis-configuration). The photo-switching behavior showed that A11 had outstanding anti-fatigue properties. An in-depth analysis of the action mechanism showed that A11 could effectively inhibit biofilm formation and the expression of relevant virulence factors. This performance could be dynamically regulated via loading with private light-switch property. CONCLUSION: In this work, designed light-controlled azo molecules provide a new model for resisting bacterial infection via dynamic regulation of bacterial biofilm formation. © 2024 Society of Chemical Industry.

3.
EMBO Rep ; 2024 Oct 10.
Article de Anglais | MEDLINE | ID: mdl-39390258

RÉSUMÉ

Zinc transporter 1 (ZnT1), the principal carrier of cytosolic zinc to the extracellular milieu, is important for cellular zinc homeostasis and resistance to zinc toxicity. Despite recent advancements in the structural characterization of various zinc transporters, the mechanism by which ZnTs-mediated Zn2+ translocation is coupled with H+ or Ca2+ remains unclear. To visualize the transport dynamics, we determined the cryo-electron microscopy (cryo-EM) structures of human ZnT1 at different functional states. ZnT1 dimerizes via extensive interactions between the cytosolic (CTD), the transmembrane (TMD), and the unique cysteine-rich extracellular (ECD) domains. At pH 7.5, both protomers adopt an outward-facing (OF) conformation, with Zn2+ ions coordinated at the TMD binding site by distinct compositions. At pH 6.0, ZnT1 complexed with Zn2+ exhibits various conformations [OF/OF, OF/IF (inward-facing), and IF/IF]. These conformational snapshots, together with biochemical investigation and molecular dynamic simulations, shed light on the mechanism underlying the proton-dependence of ZnT1 transport.

4.
iScience ; 27(9): 110836, 2024 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-39310774

RÉSUMÉ

Histological grading is the key factors affecting the prognosis and instructive in guiding treatment and assessing recurrence in non-functional pancreatic neuroendocrine tumor (NF-Pan-NET). Approximately one-third of patients without copy number variation (CNV) alteration and the prognosis of these patients are better than that of patients with CNV alteration. However, the difference between CNV and histological grading is unclear. Here, we analyzed the heterogeneity of tumor cells according to two classification criteria, genomic instability (including CNV alteration and tumor mutation burden) and histological grading. We revealed that the activated core pathways of tumor cells were significantly different under different histological grading's and genomic instability patterns. We also found that tip cells, lymphatic endothelial cells, macrophages, CD1A + dendritic cell, Treg, MAIT, ILC, and CAFs might participate in the process of hepatic metastases, which will facilitate the understanding of the patterns to decode the malignant potential and of NF-Pan-NET.

5.
Article de Anglais | MEDLINE | ID: mdl-39259982

RÉSUMÉ

Obesity and type 2 diabetes mellitus (T2DM) impact more than 2.5 billion adults worldwide, necessitating innovative therapeutic approaches. Unimolecular polypharmacology, which involves designing single molecules to target multiple receptors or pathways simultaneously, has revolutionized treatment strategies. Blockbuster drugs such as tirzepatide and retatrutide have shown unprecedented success in managing obesity and T2DM, demonstrating superior efficacy compared to conventional single agonists. Tirzepatide, in particular, has garnered tremendous attention for its remarkable effectiveness in promoting weight loss and improving glycemic control, while offering additional cardiovascular and renal benefits. Despite their promises, such therapeutic agents also face challenges that include gastrointestinal side effects, patient compliance issues, and body weight rebound after cessation of the treatment. Nonetheless, the development of these therapies marks a significant leap forward, underscoring the transformative potential of unimolecular polypharmacology in addressing metabolic diseases and paving the way for future innovations in personalized medicine.

6.
Heliyon ; 10(18): e37857, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39323779

RÉSUMÉ

Background: Intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) poses a considerable challenge to patients and their families due to its severe complications. Previous researches have highlighted the critical role of immune disorders in its pathogenesis. However, fragmented studies based on isolated cases hinder a comprehensive understanding of this deadly illness. This study aimed to explore the overall landscape of peripheral blood mononuclear cells (PBMCs) in IVIG-resistant KD patients using single-cell RNA sequencing (scRNA-seq). Methods: The scRNA-seq was used to characterize the transcriptomic profiles of IVIG-resistant KD patients, IVIG-responsive KD patients, and healthy controls. Data quality control (QC) and subsequent analysis were conducted using various R packages. These included DoubletFinder and Harmony for QC, Seurat and SingleR for identifying and annotating major cell types, ggpubr for calculating and visualizing the percentages of each cell type, Seurat for characterizing differentially expressed genes (DEGs) between groups, pheatmap for visualizing the DEGs, clusterProfiler for performing Gene Ontology (GO) enrichment analysis of DEGs, scRepertoire for TCR and BCR data analysis, Monocle for assessing cell differentiation trajectories, and CellChat for intercellular interaction evaluation. Results: High-quality single-cell transcriptome data from 12 participants were analyzed, including five with IVIG-resistant KD, four with IVIG-responsive KD, and three healthy controls. We identified 10 major cell types and observed that the differentiation of CD8+ effector T cells was impeded in IVIG-resistant KD patients with coronary artery lesion (CAL) according to cell differentiation trajectory analysis. Subsequent cell communication analysis demonstrated that myeloid cluster with high expression of LCN2, S100P, and LTF played a key role, potentially signaling through MIF-CD74/CXCR4 and MIF-CD74/CD44 ligand-receptor pairs. Conclusion: Complex immunopathological changes occur during the development of CAL in IVIG-resistant KD. Stunted differentiation of CD8+ effector T cells is noted in KD-CAL. Interactions between myeloid cells and T cells activates multiple inflammatory signaling pathways, with ligand-receptor pairs, including MIF-CD74/CXCR4 and MIF-CD74/CD44, potentially playing crucial roles.

7.
World J Psychiatry ; 14(9): 1308-1318, 2024 Sep 19.
Article de Anglais | MEDLINE | ID: mdl-39319223

RÉSUMÉ

BACKGROUND: Generalized anxiety disorder (GAD) is a relatively common mental disorder. Recently, inflammation, an important factor for the development of depression, has attracted increasing attention. Several studies have shown that inflammatory cytokines can affect the pathophysiological processes of several nervous system diseases. We hypothesized that there is a correlation between the levels of lipopolysaccharide (LPS)-stimulated inflammatory cytokines and the clinical symptoms of GAD. AIM: To investigate the predictive effect of LPS-stimulated inflammatory cytokines on symptoms of GAD. METHODS: This was a cross-sectional study in which 89 patients with GAD diagnosed at The First Hospital of Hebei Medical University from January 2022 to December 2022 and 70 individuals without anxiety and depression (controls) during the same period were included. Fasting venous blood was collected from all the subjects in heparin tubes, and another 3 ml of blood was supplemented with LPS (10 ng/ml). The plasma levels of 12 cytokines [Interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-17A, IL-12p70, and IFN-α] were detected. RESULTS: Post-LPS stimulation, the levels of IL-1ß, IL-6, IL-8, IL-10, and TNF-α in both the control and GAD groups were significantly elevated above those in the nonstimulated groups, with IL-6 and IL-8 showing marked increases. Increases in IL-8 and TNF-α were statistically significant in the GAD group (P < 0.05). IL-1ß, IL-6, IL-8, IL-10, and TNF-α were found to be significantly correlated with Hamilton Anxiety Rating Scale (HAMA) scores (P < 0.05). A negative correlation was observed between IL-10 levels and HAMA scores. Further analysis revealed that TNF-α was associated with mental anxiety, whereas IL-1ß, IL-8, and IL-10 were associated with physical anxiety symptoms, with IL-10 showing a negative correlation with physical anxiety. IL-6 was associated with both mental and physical aspects of anxiety. CONCLUSION: The physical symptoms of GAD are related to inflammatory factors. IL-1ß, IL-8, IL-10, and TNF-a can be used as predictors of physical or mental anxiety in patients with GAD.

8.
World J Gastrointest Surg ; 16(7): 1973-1980, 2024 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-39087097

RÉSUMÉ

Among minimally invasive surgical procedures, colorectal surgery is associated with a notably higher incidence of incisional hernia (IH), ranging from 1.7% to 24.3%. This complication poses a significant burden on the healthcare system annually, necessitating urgent attention from surgeons. In a study published in the World Journal of Gastrointestinal Surgery, Fan et al compared the incidence of IH among 1614 patients who underwent laparoscopic colorectal surgery with different extraction site locations and evaluated the risk factors associated with its occurrence. This editorial analyzes the current risk factors for IH after laparoscopic colorectal surgery, emphasizing the impact of obesity, surgical site infection, and the choice of incision location on its development. Furthermore, we summarize the currently available preventive measures for IH. Given the low surgical repair rate and high recurrence rate associated with IH, prevention deserves greater research and attention compared to treatment.

9.
World J Gastrointest Surg ; 16(7): 1969-1972, 2024 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-39087120

RÉSUMÉ

This editorial discusses the article "Analysis of the impact of immunotherapy efficacy and safety in patients with gastric cancer and liver metastasis" published in the latest edition of the World Journal of Gastrointestinal Surgery. Immunotherapy has achieved outstanding success in tumor treatment. However, the presence of liver metastasis (LM) restrains the efficacy of immunotherapy in various tumors, including lung cancer, colorectal cancer, renal cell carcinoma, melanoma, and gastric cancer. A decrease in CD8+ T cells and nature killer cells, along with an increase in macrophages and regulatory T cells, was observed in the microenvironment of LM, leading to immunotherapy resistance. More studies are necessary to determine the best strategy for enhancing the effectiveness of immunotherapy in patients with LM.

10.
Heliyon ; 10(15): e35362, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-39170309

RÉSUMÉ

Mahvash disease, a rare autosomal recessive metabolic disorder characterized by biallelic loss-of-function mutations in the glucagon receptor gene (GCGR), induces significant pancreatic hyperglucagonemia, resulting in α-cell hyperplasia and occasional hypoglycemia. Utilizing CRISPR-Cas9 technology, we engineered a mouse model, designated as Gcgr V369M/V369M, harboring a homozygous V369M substitution in the glucagon receptor (GCGR). Although wild-type (WT) and Gcgr V369M/V369M mice exhibited no discernible difference in appearance or weight, adult Gcgr V369M/V369M mice, approximately 12 months of age, displayed a notable decrease in fasting blood glucose levels and elevated the levels of cholesterol and low-density lipoprotein-cholesterol. Moreover, plasma amino acid levels such as alanine (Ala), proline (Pro) and arginine (Arg) were elevated in Gcgr V369M/V369M mice contributing to α-cell proliferation and hyperglucagonemia. Despite sustained α-cell hyperplasia and increased circulating glucagon levels in Gcgr V369M/V369M mice, metabolic disparities between the two groups gradually waned with age accompanied by a reduction in α-cell hyperplasia. Throughout the lifespan of the mice (up to approximately 30 months), pancreatic neuroendocrine tumors (PNETs) did not manifest. This prolonged observation of metabolic alterations in Gcgr V369M/V369M mice furnishes valuable insights for a deeper comprehension of mild Mahvash disease in humans.

11.
Metab Brain Dis ; 39(6): 1099-1108, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38995495

RÉSUMÉ

Increasing evidences implicate vital role of neuronal damage in the development of hepatic encephalopathy (HE). Neurofilament light chain (NfL) is the main frame component of neurons and is closely related to axonal radial growth and neuronal structural stability. We hypothesized that NfL as a biomarker of axonal injury may contribute to early diagnosis of HE. This study recruited 101 patients with liver cirrhosis, 10 healthy individuals, and 7 patients with Parkinson's disease. Minimal hepatic encephalopathy (MHE) was diagnosed using psychometric hepatic encephalopathy score. Serum NfL levels were measured by the electrochemiluminescence immunoassay. Serum NfL levels in cirrhotic patients with MHE were significantly higher than cirrhotic patients without MHE, and increased accordingly with the aggravation of HE. Serum NfL levels were associated with psychometric hepatic encephalopathy score, Child-Pugh score, model for end-stage liver disease score, and days of hospitalization. Additionally, serum NfL was an independent predictor of MHE (odds ratio of 1.020 (95% CI 1.005-1.034); P = 0.007). The discriminative abilities of serum NfL were high for identifying MHE (AUC of 0.8134 (95% CI 0.7130-0.9219); P ˂ 0.001) and OHE (AUC of 0.8852 (95% CI 0.8117-0.9587); P ˂ 0.001). Elevated serum NfL levels correlated with the presence of MHE and associated with the severity of HE, are expected to be a biomarker in patients with cirrhosis. Our study suggested that neuronal damage may play a critical role in the development of HE.


Sujet(s)
Marqueurs biologiques , Encéphalopathie hépatique , Cirrhose du foie , Protéines neurofilamenteuses , Humains , Encéphalopathie hépatique/sang , Encéphalopathie hépatique/diagnostic , Mâle , Femelle , Protéines neurofilamenteuses/sang , Adulte d'âge moyen , Cirrhose du foie/sang , Cirrhose du foie/complications , Marqueurs biologiques/sang , Sujet âgé , Adulte
13.
Heliyon ; 10(11): e31705, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38845982

RÉSUMÉ

Acute myeloid leukemia (AML) is a prevalent hematological malignancy among adults. Recent studies suggest that the length of telomeres could significantly affect both the risk of developing AML and the overall survival (OS). Despite the limited focus on the prognostic value of telomere-related genes (TRGs) in AML, our study aims at addressing this gap by compiling a list of TRGs from TelNet, as well as collecting clinical information and TRGs expression data through the Gene Expression Omnibus (GEO) database. The GSE37642 dataset, sourced from GEO and based on the GPL96 platform, was divided into training and validation sets at a 6:4 ratio. Additionally, the GSE71014 dataset (based on the GPL10558 platform), GSE12417 dataset (based on the GPL96 and GPL570 platforms), and another portion of the GSE37642 dataset (based on the GPL570 platform) were designated as external testing sets. Univariate Cox regression analysis identified 96 TRGs significantly associated with OS. Subsequent Lasso-Cox stepwise regression analysis pinpointed eight TRGs (MCPH1, SLC25A6, STK19, PSAT1, KCTD15, DNMT3B, PSMD5, and TAF2) exhibiting robust predictive potential for patient survival. Both univariate and multivariate survival analyses unveiled TRG risk scores and age as independent prognostic variables. To refine the accuracy of survival prognosis, we developed both a nomogram integrating clinical parameters and a predictive risk score model based on TRGs. In subsequent investigations, associations were emphasized not solely regarding the TRG risk score and immune infiltration patterns but also concerning the response to immune-checkpoint inhibitor (ICI) therapy. In summary, the establishment of a telomere-associated genetic risk model offers a valuable tool for prognosticating AML outcomes, thereby facilitating informed treatment decisions.

14.
Signal Transduct Target Ther ; 9(1): 139, 2024 May 29.
Article de Anglais | MEDLINE | ID: mdl-38811552

RÉSUMÉ

Conventional type 1 dendritic cells (cDC1) are the essential antigen-presenting DC subset in antitumor immunity. Suppressing B-cell lymphoma 9 and B-cell lymphoma 9-like (BCL9/BCL9L) inhibits tumor growth and boosts immune responses against cancer. However, whether oncogenic BCL9/BCL9L impairs antigen presentation in tumors is still not completely understood. Here, we show that targeting BCL9/BCL9L enhanced antigen presentation by stimulating cDC1 activation and infiltration into tumor. Pharmacological inhibition of BCL9/BCL9L with a novel inhibitor hsBCL9z96 or Bcl9/Bcl9l knockout mice markedly delayed tumor growth and promoted antitumor CD8+ T cell responses. Mechanistically, targeting BCL9/BCL9L promoted antigen presentation in tumors. This is due to the increase of cDC1 activation and tumor infiltration by the XCL1-XCR1 axis. Importantly, using single-cell transcriptomics analysis, we found that Bcl9/Bcl9l deficient cDC1 were superior to wild-type (WT) cDC1 at activation and antigen presentation via NF-κB/IRF1 signaling. Together, we demonstrate that targeting BCL9/BCL9L plays a crucial role in cDC1-modulated antigen presentation of tumor-derived antigens, as well as CD8+ T cell activation and tumor infiltration. Targeting BCL9/BCL9L to regulate cDC1 function and directly orchestrate a positive feedback loop necessary for optimal antitumor immunity could serve as a potential strategy to counter immune suppression and enhance cancer immunotherapy.


Sujet(s)
Présentation d'antigène , Cellules dendritiques , Animaux , Humains , Souris , Présentation d'antigène/immunologie , Présentation d'antigène/génétique , Lymphocytes T CD8+/immunologie , Lymphocytes T CD8+/anatomopathologie , Cellules dendritiques/immunologie , Cellules dendritiques/anatomopathologie , Souris knockout , Tumeurs/immunologie , Tumeurs/génétique , Tumeurs/anatomopathologie , Récepteurs aux chimiokines , Facteurs de transcription/génétique , Facteurs de transcription/immunologie
16.
Nature ; 630(8015): 247-254, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38750358

RÉSUMÉ

The noradrenaline transporter has a pivotal role in regulating neurotransmitter balance and is crucial for normal physiology and neurobiology1. Dysfunction of noradrenaline transporter has been implicated in numerous neuropsychiatric diseases, including depression and attention deficit hyperactivity disorder2. Here we report cryo-electron microscopy structures of noradrenaline transporter in apo and substrate-bound forms, and as complexes with six antidepressants. The structures reveal a noradrenaline transporter dimer interface that is mediated predominantly by cholesterol and lipid molecules. The substrate noradrenaline binds deep in the central binding pocket, and its amine group interacts with a conserved aspartate residue. Our structures also provide insight into antidepressant recognition and monoamine transporter selectivity. Together, these findings advance our understanding of noradrenaline transporter regulation and inhibition, and provide templates for designing improved antidepressants to treat neuropsychiatric disorders.


Sujet(s)
Antidépresseurs , Cryomicroscopie électronique , Transporteurs de la norépinéphrine , Norépinéphrine , Multimérisation de protéines , Humains , Antidépresseurs/composition chimique , Antidépresseurs/métabolisme , Antidépresseurs/pharmacologie , Apoprotéines/composition chimique , Apoprotéines/métabolisme , Apoprotéines/ultrastructure , Acide aspartique/composition chimique , Acide aspartique/métabolisme , Sites de fixation , Cholestérol/métabolisme , Cholestérol/composition chimique , Modèles moléculaires , Norépinéphrine/métabolisme , Norépinéphrine/composition chimique , Transporteurs de la norépinéphrine/antagonistes et inhibiteurs , Transporteurs de la norépinéphrine/composition chimique , Transporteurs de la norépinéphrine/métabolisme , Transporteurs de la norépinéphrine/ultrastructure , Liaison aux protéines , Spécificité du substrat
18.
Cell Discov ; 10(1): 18, 2024 Feb 13.
Article de Anglais | MEDLINE | ID: mdl-38346960

RÉSUMÉ

Class B1 G protein-coupled receptors (GPCRs) are important regulators of many physiological functions such as glucose homeostasis, which is mainly mediated by three peptide hormones, i.e., glucagon-like peptide-1 (GLP-1), glucagon (GCG), and glucose-dependent insulinotropic polypeptide (GIP). They trigger a cascade of signaling events leading to the formation of an active agonist-receptor-G protein complex. However, intracellular signal transducers can also activate the receptor independent of extracellular stimuli, suggesting an intrinsic role of G proteins in this process. Here, we report cryo-electron microscopy structures of the human GLP-1 receptor (GLP-1R), GCG receptor (GCGR), and GIP receptor (GIPR) in complex with Gs proteins without the presence of cognate ligands. These ligand-free complexes share a similar intracellular architecture to those bound by endogenous peptides, in which, the Gs protein alone directly opens the intracellular binding cavity and rewires the extracellular orthosteric pocket to stabilize the receptor in a state unseen before. While the peptide-binding site is partially occupied by the inward folded transmembrane helix 6 (TM6)-extracellular loop 3 (ECL3) juncture of GIPR or a segment of GCGR ECL2, the extracellular portion of GLP-1R adopts a conformation close to the active state. Our findings offer valuable insights into the distinct activation mechanisms of these three important receptors. It is possible that in the absence of a ligand, the intracellular half of transmembrane domain is mobilized with the help of Gs protein, which in turn rearranges the extracellular half to form a transitional conformation, facilitating the entry of the peptide N-terminus.

19.
Eur J Pharmacol ; 968: 176419, 2024 Apr 05.
Article de Anglais | MEDLINE | ID: mdl-38360293

RÉSUMÉ

Glucagon-like peptide-1 receptor (GLP-1R) is a prime drug target for type 2 diabetes and obesity. The ligand initiated GLP-1R interaction with G protein has been well studied, but not with ß-arrestin 1/2. Therefore, bioluminescence resonance energy transfer (BRET), mutagenesis and an operational model were used to evaluate the roles of 85 extracellular surface residues on GLP-1R in ß-arrestin 1/2 recruitment triggered by three representative GLP-1R agonists (GLP-1, exendin-4 and oxyntomodulin). Residues selectively regulated ß-arrestin 1/2 recruitment for diverse ligands, and ß-arrestin isoforms were identified. Mutation of residues K130-S136, L142 and Y145 on the transmembrane helix 1 (TM1)-extracellular domain (ECD) linker decreased ß-arrestin 1 recruitment but increased ß-arrestin 2 recruitment. Other extracellular loop (ECL) mutations, including P137A, Q211A, D222A and M303A selectively affected ß-arrestin 1 recruitment while D215A, L217A, Q221A, S223A, Y289A, S301A, F381A and I382A involved more in ß-arrestin 2 recruitment for the ligands. Oxyntomodulin engaged more broadly with GLP-1R extracellular surface to drive ß-arrestin 1/2 recruitment than GLP-1 and exendin-4; I147, W214 and L218 involved in ß-arrestin 1 recruitment, while L141, D215, L218, D293 and F381 in ß-arrestin 2 recruitment for oxyntomodulin particularly. Additionally, the non-conserved residues on ß-arrestin 1/2 C-domains contributed to interaction with GLP-1R. Further proteomic profiling of GLP-1R stably expressed cell line upon ligand stimulation with or without ß-arrestin 1/2 overexpression demonstrated both commonly and biasedly regulated proteins and pathways associated with cognate ligands and ß-arrestins. Our study offers valuable information about ligand induced ß-arrestin recruitment mediated by GLP-1R and consequent intracellular signaling events.


Sujet(s)
Diabète de type 2 , Humains , bêta-Arrestine 1/métabolisme , Exénatide/pharmacologie , bêta-Arrestine 2/génétique , bêta-Arrestine 2/métabolisme , Récepteur du peptide-1 similaire au glucagon/agonistes , Ligands , Oxyntomoduline/pharmacologie , Protéomique , Glucagon-like peptide 1/métabolisme , bêta-Arrestines/métabolisme
20.
J Am Chem Soc ; 146(8): 5295-5304, 2024 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-38363710

RÉSUMÉ

Unveiling the mechanism behind chirality propagation and dissymmetry amplification at the molecular level is of significance for the development of chiral systems with comprehensively outstanding chiroptical performances. Herein, we have presented a straightforward Cu-mediated Ullmann homocoupling approach to synthesize perylene diimide-entwined double π-helical nanoribbons encompassing dimer, trimer, and tetramer while producing homochiral or heterochiral linking of chiral centers. A significant dissymmetry amplification was achieved, with absorption dissymmetry factors (|gabs|) increasing from 0.009 to 0.017 and further to 0.019, and luminescence dissymmetry factors (|glum|) rising from 0.007 to 0.013 and eventually to 0.015 for homochiral double π-helical oligomers. The disparity of magnetic transition dipole moment (m) densities in homochiral and heterochiral tetramers by time-dependent density functional theory calculations confirmed that homochiral oligomerization can maximize the total m, which is favorable for achieving ever-increasing g factors. Notably, these double π-helices exhibited exceptional photoluminescence quantum yields (ΦPL) ranging from 83 to 95%. The circularly polarized luminescence brightness (BCPL) eventually reached a remarkable 575 M-1 cm-1 for the homochiral tetramer, which is among the highest values reported for chiral small molecules. This kind of linearly extended double π-helices offers a platform for a comprehensive understanding of the mechanism behind chirality propagation and dissymmetry amplification.

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