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1.
Sci Rep ; 14(1): 6056, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480862

RESUMO

There is limited research on the association between the alanine aminotransferase to high-density lipoprotein cholesterol ratio (ALT/HDL-C) ratio and nonalcoholic fatty liver disease (NAFLD). The purpose of the current research was to look into the connection between the ALT/HDL-C ratio and the risk of NAFLD in lean Chinese individuals. Between January 2010 and December 2014, 11,975 non-obese people participated in this prospective cohort research. The relationship between the ALT/HDL-C ratio and the risk of developing NAFLD was assessed using the Cox proportional-hazards regression model, Cox proportional hazards regression with cubic spline functions and smooth curve fitting, sensitivity analysis, and subgroup analyses. The ALT/HDL-C ratio's potential value as a NAFLD prognostic marker was to be evaluated using the receiver operating characteristic curve analysis. A total of 5419 (45.253%) women comprised the research's participant population, and the research participants' average age was 43.278 ± 14.941 years. The ALT/HDL-C ratio was 11.607 (7.973-17.422) at the median (interquartile ranges). 2087 (17.428%) patients had NAFLD diagnoses throughout a median follow-up of 24.967 months. The study's findings demonstrated a positive connection between the ALT/AHDL-C ratio and the incident NAFLD (HR = 1.037, 95% CI: 1.031-1.042) when adjusting for relevant factors. The ALT/HDL-C ratio and NAFLD risk had a nonlinear connection, with 12.963 as the ratio's inflection point. Effect sizes (HR) were 1.023 (95% CI: 1.017-1.029) and 1.204 (95% CI: 1.171-1.237), respectively, on the right and left sides of the inflection point. The sensitivity analysis also showed how reliable our findings were. According to subgroup analysis, those with BMI < 24 kg/m2 and DBP < 90 mmHg had a stronger correlation between the ALT/HDL-C ratio and NAFLD risk. The current study shows a positive and non-linear connection between the ALT/HDL-C ratio and NAFLD risk in lean Chinese individuals. When the ALT/HDL-C ratio is less than 12.963, it is significantly linked to NAFLD. Therefore, from a therapy standpoint, it is advised to keep the ALT/HDL-C ratio less than the inflection point.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , HDL-Colesterol , Alanina Transaminase , Estudos Retrospectivos , Estudos Prospectivos , China/epidemiologia
3.
Cell Discov ; 10(1): 18, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38346960

RESUMO

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.

4.
Eur J Pharmacol ; 968: 176419, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38360293

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , beta-Arrestina 1/metabolismo , Exenatida/farmacologia , beta-Arrestina 2/genética , beta-Arrestina 2/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Ligantes , Oxintomodulina/farmacologia , Proteômica , Peptídeo 1 Semelhante ao Glucagon/metabolismo , beta-Arrestinas/metabolismo
5.
MedComm (2020) ; 5(3): e479, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38414669

RESUMO

Ferroptosis is a recently discovered form of regulated cell death characterized by its distinct dependence on iron and the peroxidation of lipids within cellular membranes. Ferroptosis plays a crucial role in physiological and pathological situations and has attracted the attention of numerous scientists. Ferroptosis suppressive protein 1 (FSP1) is one of the main regulators that negatively regulates ferroptosis through the GPX4-independent FSP1-CoQ10-NAD(P)H axis and is a potential therapeutic target for ferroptosis-related diseases. However, the crystal structure of FSP1 has not been resolved, which hinders the development of therapeutic strategies targeting FSP1. To unravel this puzzle, we purified the human FSP1 (hFSP1) protein using the baculovirus eukaryotic cell expression system and solved its crystal structure at a resolution of 1.75 Å. Furthermore, we evaluated the oxidoreductase activity of hFSP1 with NADH as the substrate and identified E156 as the key amino acid in maintaining hFSP1 activity. Interestingly, our results indicated that hFSP1 exists and functions in a monomeric state. Mutagenesis analysis revealed the critical role of the C-terminal domain in the binding of substrate. These findings significantly enhance our understanding of the functional mechanism of FSP1 and provide a precise model for further drug development.

6.
Eur J Med Res ; 29(1): 140, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388456

RESUMO

OBJECTIVES: The present body of evidence regarding the correlation between the estimated glomerular filtration rate (eGFR) and the reversal of impaired fasting glucose (IFG) to normoglycemia remains constrained. Consequently, the objective of our study is to examine the relationship between eGFR and the restoration of normoglycemia in individuals with IFG. METHODS: This retrospective cohort study consecutively collected data from 24,541 non-selective participants with IFG at Rich Healthcare Group in China from January 2010 to 2016. We aimed to investigate the association between baseline eGFR and reversion to normoglycemia using the Cox proportional-hazards regression model. Through the utilization of a Cox proportional hazards regression model featuring cubical spline smoothing, we were able to ascertain the non-linear correlation between eGFR and the return to normoglycemia. Furthermore, various sensitivity and subgroup analyses were carried out, and a competing risk multivariate Cox regression was employed to examine the progression to diabetes as a competing risk for the reversal of normoglycemic events. RESULTS: In our study, comprising 24,541 participants, the average age was 49.25 ± 13.77 years, with 66.28% being male. The baseline eGFR mean was 104.16 ± 15.78 ml/min per 1.73 m2. During a median follow-up period of 2.89 years, we observed a reversion rate to normoglycemia of 45.50%. Upon controlling for covariates, our findings indicated a positive correlation between eGFR and the probability of returning to normoglycemia (HR = 1.008, 95% CI 1.006-1.009). In addition, a non-linear association was observed between eGFR and the likelihood of transitioning from IFG to normoglycemia. The inflection point of eGFR was found to be 111.962 ml/min per 1.73 m2, with HRs of 1.003 (95% CI 1.001, 1.005) on the left side of the point and 1.019 (95% CI 1.015, 1.022) on the right side. Our robust results were supported by competing risks multivariate Cox's regression and sensitivity analysis. CONCLUSIONS: The findings of our investigation indicate a favorable and non-linear correlation between eGFR and the restoration of normoglycemia in Chinese individuals with IFG. Specifically, a reduction in renal function at an early stage in these patients may considerably diminish the likelihood of attaining normoglycemia.


Assuntos
Glicemia , Estado Pré-Diabético , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Taxa de Filtração Glomerular , Jejum , Fatores de Risco
7.
iScience ; 27(2): 108896, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38318373

RESUMO

Liver metastasis (LM) is the primary cause of cancer-related mortality in late-stage breast cancer (BC) patients. Here we report an in-depth analysis of the transcriptional landscape of LM of 11 patients with secondary hepatic carcinoma at single-cell resolution. Our study reveals that terminally exhausted CD4+ and dysfunctional CD8+ T cells were enriched in LM along with low antigen presentation. We also found that macrophages were associated with the tumor infiltrating CD4+ T cells, while FCN3+ macrophages, type 1 conventional dendritic cells (cDC1) and LAMP3+ DC regulated T cell functions, probably via antigen processing and presentation. Major histocompatibility complex expression in FCN3+ macrophage, cDC1 and LAMP3+ DC was reduced in LM compared to those in normal tissues and primary BC. Malfunctioned antigen presentation in these cells is linked to a worse prognosis in invasive BC and hepatocellular carcinoma. Our results provide valuable insights into the role of tumor infiltrating T cells in LM.

8.
Adv Sci (Weinh) ; 11(12): e2306993, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38233212

RESUMO

Passivating contactsin heterojunction (HJ) solar cells have shown great potential in reducing recombination losses, and thereby achieving high power conversion efficiencies in photovoltaic devices. In this direction, carbon nanomaterials have emerged as a promising option for carbon/silicon (C/Si) HJsolar cells due to their tunable band structure, wide spectral absorption, high carrier mobility, and properties such as multiple exciton generation. However, the current limitations in efficiency and active area have hindered the industrialization of these devices. In this review, they examine the progress made in overcoming these constraints and discuss the prospect of achieving high power conversion efficiency (PCE) C/Si HJ devices. A C/Si HJ solar cell is also designed by introducing an innovative interface passivation strategy to further boost the PCE and accelerate the large area preparationof C/Si devices. The physical principle, device design scheme, and performanceoptimization approaches of this passivated C/Si HJ cells are discussed. Additionally, they outline potential future pathways and directions for C/Si HJ devices, including a reduction in their cost to manufacture and their incorporation intotandem solar cells. As such, this review aims to facilitate a deeperunderstanding of C/Si HJ solar cells and provide guidance for their further development.

10.
Elife ; 122023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37955640

RESUMO

As a major class of biomolecules, carbohydrates play indispensable roles in various biological processes. However, it remains largely unknown how carbohydrates directly modulate important drug targets, such as G-protein coupled receptors (GPCRs). Here, we employed P2Y purinoceptor 14 (P2Y14), a drug target for inflammation and immune responses, to uncover the sugar nucleotide activation of GPCRs. Integrating molecular dynamics simulation with functional study, we identified the uridine diphosphate (UDP)-sugar-binding site on P2Y14, and revealed that a UDP-glucose might activate the receptor by bridging the transmembrane (TM) helices 2 and 7. Between TM2 and TM7 of P2Y14, a conserved salt bridging chain (K2.60-D2.64-K7.35-E7.36 [KDKE]) was identified to distinguish different UDP-sugars, including UDP-glucose, UDP-galactose, UDP-glucuronic acid, and UDP-N-acetylglucosamine. We identified the KDKE chain as a conserved functional motif of sugar binding for both P2Y14 and P2Y purinoceptor 12 (P2Y12), and then designed three sugar nucleotides as agonists of P2Y12. These results not only expand our understanding for activation of purinergic receptors but also provide insights for the carbohydrate drug development for GPCRs.


Sugars and other types of carbohydrates are biomolecules which play a range of key roles in the body. In particular, they are important messengers that help to coordinate immune responses. For example, a carbohydrate known as UDP-Glucose (a kind of UDP-sugar) can activate P2Y14, a receptor studded through the surface of many cells; this event then triggers a cascade of molecular events associated with asthma, kidney injury and lung inflammation. Yet it remains unclear how exactly UDP-Glucose recognizes P2Y14 ­ and, more broadly, how carbohydrates interact with purinergic receptors, the class of proteins that P2Y14 belongs to. To examine this question, Zhao et al. combined functional experiments in the laboratory with molecular dynamics simulations, a computational approach. This work revealed that UDP-Glucose may activate P2Y14 by bridging its segments anchored within the cell membrane. A component of P2Y14, known as the KDKE chain, was found to have an important role in distinguishing between highly similar types of UDP-sugars. This allowed Zhao et al. to design three sugar molecules which could activate another purinergic receptor that also contained a KDKE chain. Purinergic receptors are promising therapeutic targets. A finer understanding of how they recognise the molecules that activate them is therefore important to be able to identify and design new drug compounds.


Assuntos
Nucleotídeos , Receptores Purinérgicos , Uridina Difosfato Glucose , Açúcares , Receptores Purinérgicos P2Y
11.
Opt Express ; 31(20): 33719-33731, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859145

RESUMO

Large aperture ground-based segmented telescopes typically use electrical edge sensors to detect co-phase errors. However, complex observing environments can lead to zero-point drift of the edge sensors, making it challenging to maintain the long-term co-phase of the segmented primary mirror using only edge sensors. Therefore, employing optical piston error detection methods for short-term calibration of edge sensors can address the issue of zero-point drift in the sensors. However, atmospheric turbulence can affect calibration accuracy based on the observational target. To achieve high-precision calibration of electrical edge sensors, this study investigates the impact of atmospheric turbulence on optical piston error detection. Based on simulated results, it is found that the actual measured piston error in the presence of atmospheric turbulence is the difference between the average phases of the two segments. Subsequently, optical piston error detection experiments were conducted in a segmented mirror system under simulated turbulent conditions with varying turbulence intensities. Experimental studies have shown that the detection accuracy of the optical method is almost the same as without turbulence when using a detection aperture size that is 0.82 times the atmospheric coherence length and an exposure time of at least 40 ms. The root mean square of the cross-calibration is better than 3 nm. These experimental results indicate that under conditions of good atmospheric seeing, the optical piston error detection method can meet the short-term calibration requirements of edge sensors by setting reasonable detection area size and exposure time. It may even be possible to directly use optical detection methods to replace edge sensors for real-time detection of piston errors.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37891366

RESUMO

Apoptosis and inflammation of vascular endothelial cells (VECs) are the most important causes of deep vein thrombosis (DVT). cAMP response element binding protein 1 (CREB1) encodes a transcription factor that binds as a homodimer to the cAMP-responsive element and can promote inflammation. CREB1 is found to be upregulated in the plasma of patients with venous thromboembolism. However, the biological functions of CREB1 in DVT remain unknown. We evaluated the effect of CREB1 in a rat model of inferior vena cava (IVA) stenosis-induced DVT. IVC stenosis resulted in stable thrombus, inflammatory response and CREB1 upregulation, whereas CREB1 knockdown inhibited thrombus and inflammation in DVT rats. In vitro analysis showed that CREB1 knockdown inhibited VEC apoptosis. Mechanistically, CREB1 knockdown reduced Ribosomal protein L9 (RPL9) expression and blocked the NF-κB pathway. Therefore, CREB1 may become a potential therapeutic target of DVT prevention.

13.
Proc Natl Acad Sci U S A ; 120(41): e2306145120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37792509

RESUMO

Glucose-dependent insulinotropic polypeptide receptor (GIPR) is a potential drug target for metabolic disorders. It works with glucagon-like peptide-1 receptor and glucagon receptor in humans to maintain glucose homeostasis. Unlike the other two receptors, GIPR has at least 13 reported splice variants (SVs), more than half of which have sequence variations at either C or N terminus. To explore their roles in endogenous peptide-mediated GIPR signaling, we determined the cryoelectron microscopy (cryo-EM) structures of the two N terminus-altered SVs (referred as GIPR-202 and GIPR-209 in the Ensembl database, SV1 and SV2 here, respectively) and investigated the outcome of coexpressing each of them in question with GIPR in HEK293T cells with respect to ligand binding, receptor expression, cAMP (adenosine 3,5-cyclic monophosphate) accumulation, ß-arrestin recruitment, and cell surface localization. It was found that while both N terminus-altered SVs of GIPR neither bound to the hormone nor elicited signal transduction per se, they suppressed ligand binding and cAMP accumulation of GIPR. Meanwhile, SV1 reduced GIPR-mediated ß-arrestin 2 responses. The cryo-EM structures of SV1 and SV2 showed that they reorganized the extracellular halves of transmembrane helices 1, 6, and 7 and extracellular loops 2 and 3 to adopt a ligand-binding pocket-occupied conformation, thereby losing binding ability to the peptide. The results suggest a form of signal bias that is constitutive and ligand-independent, thus expanding our knowledge of biased signaling beyond pharmacological manipulation (i.e., ligand specific) as well as constitutive and ligand-independent (e.g., SV1 of the growth hormone-releasing hormone receptor).


Assuntos
Polipeptídeo Inibidor Gástrico , Receptores dos Hormônios Gastrointestinais , Humanos , Polipeptídeo Inibidor Gástrico/genética , Polipeptídeo Inibidor Gástrico/metabolismo , Polipeptídeo Inibidor Gástrico/farmacologia , Ligantes , Microscopia Crioeletrônica , Células HEK293 , Transdução de Sinais/fisiologia , Receptores dos Hormônios Gastrointestinais/genética , Receptores dos Hormônios Gastrointestinais/química , Receptores dos Hormônios Gastrointestinais/metabolismo , Peptídeos , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo
14.
J Med Chem ; 66(17): 11855-11868, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37669317

RESUMO

Despite the essential roles of Frizzled receptors (FZDs) in mediating Wnt signaling in embryonic development and tissue homeostasis, ligands targeting FZDs are rare. A few antibodies and peptide modulators have been developed that mainly bind to the family-conserved extracellular cysteine-rich domain of FZDs, while the canonical binding sites in the transmembrane domain (TMD) are far from sufficiently addressed. Based on the recent structures of FZDs, we explored small-molecule ligand discovery by targeting TMD. From the ChemDiv library with ∼1.6 million compounds, we identified compound F7H as an antagonist of FZD7 with an IC50 at 1.25 ± 0.38 µM. Focusing on this hit, the structural dissection study, together with computing studies such as molecular docking, molecular dynamics simulation, and free energy perturbation calculations, defined the binding pocket with key residue recognition. Our results revealed the structural basis of ligand recognition and demonstrated the feasibility of structure-guided ligand discovery for FZD7-TMD.


Assuntos
Anticorpos , Receptores Frizzled , Feminino , Gravidez , Humanos , Ligantes , Simulação de Acoplamento Molecular , Sítios de Ligação
15.
iScience ; 26(10): 107243, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37767002

RESUMO

Image-based AI has thrived as a potentially revolutionary tool for predicting molecular biomarker statuses, which aids in categorizing patients for appropriate medical treatments. However, many methods using hematoxylin and eosin-stained (H&E) whole-slide images (WSIs) have been found to be inefficient because of the presence of numerous uninformative or irrelevant image patches. In this study, we introduced the region of biomarker relevance (ROB) concept to identify the morphological areas most closely associated with biomarkers for accurate status prediction. We actualized this concept within a framework called saliency ROB search (SRS) to enable efficient and effective predictions. By evaluating various lung adenocarcinoma (LUAD) biomarkers, we showcased the superior performance of SRS compared to current state-of-the-art AI approaches. These findings suggest that AI tools, built on the ROB concept, can achieve enhanced molecular biomarker prediction accuracy from pathological images.

16.
Proc Natl Acad Sci U S A ; 120(34): e2304071120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37585458

RESUMO

Class IA phosphoinositide 3-kinase alpha (PI3Kα) is an important drug target because it is one of the most frequently mutated proteins in human cancers. However, small molecule inhibitors currently on the market or under development have safety concerns due to a lack of selectivity. Therefore, other chemical scaffolds or unique mechanisms of catalytic kinase inhibition are needed. Here, we report the cryo-electron microscopy structures of wild-type PI3Kα, the dimer of p110α and p85α, in complex with three Y-shaped ligands [cpd16 (compound 16), cpd17 (compound 17), and cpd18 (compound 18)] of different affinities and no inhibitory effect on the kinase activity. Unlike ATP-competitive inhibitors, cpd17 adopts a Y-shaped conformation with one arm inserted into a binding pocket formed by R770 and W780 and the other arm lodged in the ATP-binding pocket at an angle that is different from that of the ATP phosphate tail. Such a special interaction induces a conformation of PI3Kα resembling that of the unliganded protein. These observations were confirmed with two isomers (cpd16 and cpd18). Further analysis of these Y-shaped ligands revealed the structural basis of differential binding affinities caused by stereo- or regiochemical modifications. Our results may offer a different direction toward the design of therapeutic agents against PI3Kα.


Assuntos
Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Ligantes , Microscopia Crioeletrônica , Trifosfato de Adenosina/metabolismo
17.
Nature ; 620(7974): 676-681, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532940

RESUMO

Phosphorylation of G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) desensitizes G-protein signalling and promotes arrestin signalling, which is also modulated by biased ligands1-6. The molecular assembly of GRKs on GPCRs and the basis of GRK-mediated biased signalling remain largely unknown owing to the weak GPCR-GRK interactions. Here we report the complex structure of neurotensin receptor 1 (NTSR1) bound to GRK2, Gαq and the arrestin-biased ligand SBI-5537. The density map reveals the arrangement of the intact GRK2 with the receptor, with the N-terminal helix of GRK2 docking into the open cytoplasmic pocket formed by the outward movement of the receptor transmembrane helix 6, analogous to the binding of the G protein to the receptor. SBI-553 binds at the interface between GRK2 and NTSR1 to enhance GRK2 binding. The binding mode of SBI-553 is compatible with arrestin binding but clashes with the binding of Gαq protein, thus providing a mechanism for its arrestin-biased signalling capability. In sum, our structure provides a rational model for understanding the details of GPCR-GRK interactions and GRK2-mediated biased signalling.


Assuntos
Quinase 2 de Receptor Acoplado a Proteína G , Receptores Acoplados a Proteínas G , Transdução de Sinais , Arrestinas/metabolismo , Fosforilação , Receptores Acoplados a Proteínas G/metabolismo , Quinase 2 de Receptor Acoplado a Proteína G/biossíntese , Quinase 2 de Receptor Acoplado a Proteína G/química , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Ligantes , Ligação Proteica , Receptores de Neurotensina/metabolismo
18.
Front Microbiol ; 14: 1207490, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37608948

RESUMO

Introduction: Streptococcus intermedius is an opportunistic pathogen associated with prolonged hospital stays and high mortality rates in adults. However, little is currently known about the clinical features of Streptococcus intermedius infection in children. Methods: This retrospective case series study included 40 children diagnosed with Streptococcus intermedius, confirmed through bacterial cultures or high-throughput sequencing. Antibiotic resistance was assessed through susceptibility testing. The site and clinical manifestations were evaluated for all patients. Results: The common infection sites were the abdominal cavity, skin and soft tissue, intracranial, and invasive pulmonary, with the abdominal cavity being the most frequently affected. The drug susceptibility test showed 100% sensitivity to ceftriaxone, levofloxacin, chloramphenicol, vancomycin, and linezolid, 92.6% sensitivity to penicillin, 73.3% resistance to erythromycin, and 76.7% resistance to clindamycin. Besides antibiotic therapy, surgical intervention or pus drainage was often necessary. Lung imaging of four patients revealed pulmonary abscesses, nodules, or encapsulated pleura. Two cases yielded positive culture results, while three were identified as positive through high-throughput nucleotide sequencing of pleural effusion. Discussion: In children with Streptococcus intermedius infection, emphasis should be placed on the risk of pus or abscess formation. In cases of pulmonary abscess and pleural effusion, especially in male children, Streptococcus intermedius should be suspected even if the culture is negative. Improvements in high-throughput nucleotide sequencing are required to reduce misdiagnosis rates.

19.
BMC Pregnancy Childbirth ; 23(1): 597, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608260

RESUMO

PURPOSE: Sleep quality is an important indicator of individual quality of life, which not only affects people's mental health but is also closely related to the occurrence of many diseases. Sleep disorders associated with diabetes in pregnancy can greatly endanger the health of both mothers and babies, and their hazards are strongly associated with blood glucose levels. This study explored the quality of sleep and sleep disorders in pregnant women with diabetes. METHODS: From June 2020 to July 2021, a total of 693 patients diagnosed with diabetes during pregnancy in Gansu Provincial Maternal and Child Health Hospital were used as the experiment group, including 626 patients with gestational diabetes mellitus (GDM) and 67 patients with pregestational diabetes mellitus (PGDM). At the same time, 709 women not having diabetes were randomly selected as the control group. To obtain the general situation of the participants, the participants were surveyed using the Pittsburgh Sleep Quality Index (PSQI) and the STOP-BANG (S, Snoring; T, Tiredness; O, Observed apnea; P, high blood Pressure; B, Body mass index > 35 kg/ m2; A, Age > 50 years; N, Neck circumference > 40 cm; G, male Gender) questionnaire. The differences in sleep quality and obstructive sleep apnea-hypopnea syndrome (OSAHS) were analyzed between the experiment group and the control group by using chi-square and t-test, and the clinical features and related factors of sleep disorder were analyzed. RESULTS: Compared with the control group, the age, pre-pregnancy weight, body mass index (BMI), and neck circumference were larger in the experimental group (P < 0.05). The experimental group had higher PSQI scores for sleep quality, time to fall asleep score, sleep duration, sleep efficiency, sleep disorder, and daytime dysfunction than the control group (all P < 0.001). Specific analysis of the clinical features of sleep disorders indicated that the experimental group scored higher than the control group (P < 0.05). The analysis of the types of daytime dysfunction showed that the experiment group scored higher in terms of frequently feeling sleepy and lack of energy to do things than the control group (P < 0.05). Analysis of STOP-BANG scores indicated that the proportion of patients with GDM or PGDM having fatigue, hypertension, BMI > 35 kg/m2, and neck circumference > 40 cm was higher than that in the control group (P < 0.05). According to regression analysis, sleep quality of patients with GDM was significantly impacted by the increases in age (OR: 1.243, CI:1.197-1.290), neck circumference (OR: 1.350, CI: 1.234-1.476), PSQI score (OR: 2.124, CI:1.656-2.724), and sleep efficiency score (OR: 3.083, CI:1.534-6.195), whereas that of patients with PGDM was impacted by age (OR: 1.191, CI:1.086-1.305), neck circumference (OR: 1.981, CI: 1.469-2.673), and PSQI score (OR: 7.835, CI: 2.383-25.761). CONCLUSIONS: Pregnant women with diabetes had poorer sleep quality and a higher risk of developing OSAHS than those without diabetes. There may be some link between sleep quality and the onset of diabetic.


Assuntos
Diabetes Gestacional , Hipertensão , Apneia Obstrutiva do Sono , Criança , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Gravidez , Diabetes Gestacional/epidemiologia , Fadiga , Qualidade de Vida , Estudos Retrospectivos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Qualidade do Sono , Estudos de Casos e Controles
20.
Proc Natl Acad Sci U S A ; 120(33): e2303696120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549266

RESUMO

Glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR), two members of class B1 G protein-coupled receptors, play important roles in glucose homeostasis and energy metabolism. They share a high degree of sequence homology but have different functionalities. Unimolecular dual agonists of both receptors developed recently displayed better clinical efficacies than that of monotherapy. To study the underlying molecular mechanisms, we determined high-resolution cryo-electron microscopy structures of GLP-1R or GCGR in complex with heterotrimeric Gs protein and three GLP-1R/GCGR dual agonists including peptide 15, MEDI0382 (cotadutide) and SAR425899 with variable activating profiles at GLP-1R versus GCGR. Compared with related structures reported previously and supported by our published pharmacological data, key residues responsible for ligand recognition and dual agonism were identified. Analyses of peptide conformational features revealed a difference in side chain orientations within the first three residues, indicating that distinct engagements in the deep binding pocket are required to achieve receptor selectivity. The middle region recognizes extracellular loop 1 (ECL1), ECL2, and the top of transmembrane helix 1 (TM1) resulting in specific conformational changes of both ligand and receptor, especially the dual agonists reshaped ECL1 conformation of GLP-1R relative to that of GCGR, suggesting an important role of ECL1 interaction in executing dual agonism. Structural investigation of lipid modification showed a better interaction between lipid moiety of MEDI0382 and TM1-TM2 cleft, in line with its increased potency at GCGR than SAR425899. Together, the results provide insightful information for the design and development of improved therapeutics targeting these two receptors simultaneously.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1 , Receptores de Glucagon , Microscopia Crioeletrônica , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Ligantes , Lipídeos , Peptídeos/química , Receptores de Glucagon/agonistas
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