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1.
J Biomol Struct Dyn ; : 1-13, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38661004

ABSTRACT

The androgen receptor (AR, Uniprot: P10275) signaling plays a key role in the progression of prostate cancer, various AR-related ligands have been reported to treat prostate cancer. However, some resistance mechanisms limited the treating effect of these ligands. Since DBD binding or the allosteric binding sites in LBD of AR may allow the circumvention of some drug resistance mechanisms, anti-resistance is expected especially through the NTD (N-terminal domain) targeting. What's more, studies have shown that compounds including EPI-001 and its derivatives which bind to the Tau-5 region on NTD could be promising molecules for AR-based therapeutics. Herein, we employed aMD (accelerated molecular dynamics) simulation to fold Tau-5 unit proteins into native structure correctly. Subsequently, based on the predicted structural features of Tau-5, the virtual screening was conducted to discover new compounds targeting AR-NTD. We picked up 8 compounds (according to their docking scores and partly similar structural consists as known AR ligands) and analyzed their interaction with Tau-5, compared with the positive control EPI-001, four of the pick-up compounds showed better glide scores. Interestingly, although compound 8 had a lower docking score, it consisted of a similar component as the ligand EIQPN and the amide derivatives, this predicts that compound 8 has also the potential to be modified into an excellent AR-NTD binding molecule. These 8 compounds were all commercially available and could be tested to check whether there was a hit compound to bind the AR-NTD and to regulate its bio-activities. Together, this study described an in silico VLS approach to discover AR-NTD ligands and provided more choices for developing AR-targeted therapies.Communicated by Ramaswamy H. Sarma.

2.
Sensors (Basel) ; 24(7)2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38610277

ABSTRACT

The accurate prediction of the future trajectories of traffic participants is crucial for enhancing the safety and decision-making capabilities of autonomous vehicles. Modeling social interactions among agents and revealing the inherent relationships is crucial for accurate trajectory prediction. In this context, we propose a goal-guided and interaction-aware state refinement graph attention network (SRGAT) for multi-agent trajectory prediction. This model effectively integrates high-precision map data and dynamic traffic states and captures long-term temporal dependencies through the Transformer network. Based on these dependencies, it generates multiple potential goals and Points of Interest (POIs). Through its dual-branch, multimodal prediction approach, the model not only proposes various plausible future trajectories associated with these POIs, but also rigorously assesses the confidence levels of each trajectory. This goal-oriented strategy enables SRGAT to accurately predict the future movement trajectories of other vehicles in complex traffic scenarios. Tested on the Argoverse and nuScenes datasets, SRGAT surpasses existing algorithms in key performance metrics by adeptly integrating past trajectories and current context. This goal-guided approach not only enhances long-term prediction accuracy, but also ensures its reliability, demonstrating a significant advancement in trajectory forecasting.

3.
J Cheminform ; 16(1): 29, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38475916

ABSTRACT

Chemical structure segmentation constitutes a pivotal task in cheminformatics, involving the extraction and abstraction of structural information of chemical compounds from text-based sources, including patents and scientific articles. This study introduces a deep learning approach to chemical structure segmentation, employing a Vision Transformer (ViT) to discern the structural patterns of chemical compounds from their graphical representations. The Chemistry-Segment Anything Model (ChemSAM) achieves state-of-the-art results on publicly available benchmark datasets and real-world tasks, underscoring its effectiveness in accurately segmenting chemical structures from text-based sources. Moreover, this deep learning-based approach obviates the need for handcrafted features and demonstrates robustness against variations in image quality and style. During the detection phase, a ViT-based encoder-decoder model is used to identify and locate chemical structure depictions on the input page. This model generates masks to ascertain whether each pixel belongs to a chemical structure, thereby offering a pixel-level classification and indicating the presence or absence of chemical structures at each position. Subsequently, the generated masks are clustered based on their connectivity, and each mask cluster is updated to encapsulate a single structure in the post-processing workflow. This two-step process facilitates the effective automatic extraction of chemical structure depictions from documents. By utilizing the deep learning approach described herein, it is demonstrated that effective performance on low-resolution and densely arranged molecular structural layouts in journal articles and patents is achievable.

4.
FEBS J ; 291(8): 1795-1812, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38308810

ABSTRACT

Ataxin-2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ-expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction. Further research indicates that the polyQ tract and the N-terminal region (residues 1-784) of Atx2 are responsible for the specific sequestration. Moreover, this sequestration leads to suppression of the mTORC1 activity as represented by down-regulation of phosphorylated P70S6K, which can be reversed by overexpression of Raptor. As mTORC1 is a key regulator of autophagy, Atx2 aggregation and sequestration also induces autophagy by upregulating LC3-II and reducing phosphorylated ULK1 levels. This study proposes that Atx2 sequesters Raptor into aggregates, thereby impairing cellular mTORC1 signaling and inducing autophagy, and will be beneficial for a better understanding of the pathogenesis of SCA2 and other polyQ diseases.


Subject(s)
Ataxin-2 , Ataxin-2/genetics , Mechanistic Target of Rapamycin Complex 1/genetics , Mechanistic Target of Rapamycin Complex 1/metabolism
5.
Bioorg Chem ; 144: 107113, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38232685

ABSTRACT

Liver fibrosis is an abnormal wound-healing response to liver injuries. It can lead to liver cirrhosis, and even liver cancer and liver failure. There is a lack of treatment for liver fibrosis and it is of great importance to develop anti-fibrotic drugs. A pivotal event in the process of developing liver fibrosis is the activation of hepatic stellate cells (HSCs), in which the nuclear receptor Nur77 plays a crucial role. This study aimed to develop novel anti-fibrotic agents with Nur77 as the drug target by modifying the structure of THPN, a Nur77-binding and anti-melanoma compound. Specifically, a series of para-positioned 3,4,5-trisubstituted benzene ring compounds with long-chain backbone were generated and tested for anti-fibrotic activity. Among these compounds, compound A8 was with the most potent and Nur77-dependent inhibitory activity against TGF-ß1-induced activation of HSCs. In a crystal structure analysis, compound A8 bound Nur77 in a peg-in-hole mode as THPN did but adopted a different conformation that could interfere the Nur77 interaction with AKT, which was previous shown to be important for an anti-fibrotic activity. In a cell-based assay, compound A8 indeed impeded the interaction between Nur77 and AKT leading to the stabilization of Nur77 without the activation of AKT. In a mouse model, compound A8 effectively suppressed the activation of AKT signaling pathway and up-regulated the cellular level of Nur77 to attenuate the HSCs activation and ameliorate liver fibrosis with no significant toxic side effects. Collectively, this work demonstrated that Nur77-targeting compound A8 is a promising anti-fibrotic drug candidate.


Subject(s)
Benzene , Proto-Oncogene Proteins c-akt , Mice , Animals , Fibrosis , Liver Cirrhosis/chemically induced , Liver Cirrhosis/drug therapy , Liver Cirrhosis/metabolism
6.
Bioorg Chem ; 143: 107022, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38142558

ABSTRACT

Liver fibrosis remains a global health challenge due to its rapidly rising prevalence and limited treatment options. The orphan nuclear receptor Nur77 has been implicated in regulation of autophagy and liver fibrosis. Targeting Nur77-mediated autophagic flux may thus be a new promising strategy against hepatic fibrosis. In this study, we synthesized four types of Nur77-based thiourea derivatives to determine their anti-hepatic fibrosis activity. Among the synthesized thiourea derivatives, 9e was the most potent inhibitor of hepatic stellate cells (HSCs) proliferation and activation. This compound could directly bind to Nur77 and inhibit TGF-ß1-induced α-SMA and COLA1 expression in a Nur77-dependent manner. In vivo, 9e significantly reduced CCl4-mediated hepatic inflammation response and extracellular matrix (ECM) production, revealing that 9e is capable of blocking the progression of hepatic fibrosis. Mechanistically, 9e induced Nur77 expression and enhanced autophagic flux by inhibiting the mTORC1 signaling pathway in vitro and in vivo. Thus, the Nur77-targeted lead 9e may serve as a promising candidate for treatment of chronic liver fibrosis.


Subject(s)
Antifibrotic Agents , Thiosemicarbazones , Humans , Thiosemicarbazones/metabolism , Hepatic Stellate Cells , Liver/metabolism , Liver Cirrhosis/metabolism , Thiourea/metabolism , Carbon Tetrachloride
7.
Eur J Pharmacol ; 966: 176270, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38096970

ABSTRACT

AIM: Liver fibrosis remains a great challenge in the world. Spinosin (SPI), a natural flavonoid-C-glycoside, possesses various pharmacological activities including anti-inflammatory and anti-myocardial fibrosis effects. In this study, we investigate whether SPI can be a potential lead for the treatment of liver fibrosis and explore whether the orphan nuclear receptor Nur77, a negative regulator of liver fibrosis development, plays a critical role in SPI's action. METHODS: A dual luciferase reporter system of α-SMA was established to evaluate the effect of SPI on hepatic stellate cell (HSC) activation in LX2 and HSC-T6 cells. A mouse model of CCl4-induced liver fibrosis was used to test the efficacy of SPI against liver fibrosis. The expression levels of Nur77, inflammatory cytokines and collagen were determined by Western blotting and qPCR. Potential kinase pathways involved were also analyzed. The affinity of Nur77 with SPI was documented by fluorescence titration. RESULTS: SPI can strongly suppress TGF-ß1-mediated activation of both LX2 and HSC-T6 cells in a dose-dependent manner. SPI increases the expression of Nur77 and reduces TGF-ß1-mediated phosphorylation levels of ASK1 and p38 MAPK, which can be reversed by knocking out of Nur77. SPI strongly inhibits collagen deposition (COLA1) and reduces inflammatory cytokines (IL-6 and IL-1ß), which is followed by improved liver function in the CCl4-induced mouse model. SPI can directly bind to R515 and R563 in the Nur77-LBD pocket with a Kd of 2.14 µM. CONCLUSION: Spinosin is the major pharmacological active component of Ziziphus jujuba Mill. var. spinosa which has been frequently prescribed in traditional Chinese medicine. We demonstrate here for the first time that spinosin is a new therapeutic lead for treatment of liver fibrosis by targeting Nur77 and blocking the ASK1/p38 MAPK signaling pathway.


Subject(s)
Hepatic Stellate Cells , Transforming Growth Factor beta1 , Mice , Animals , Transforming Growth Factor beta1/metabolism , Signal Transduction , Cell Line , Liver Cirrhosis/chemically induced , Liver Cirrhosis/drug therapy , Liver Cirrhosis/metabolism , Flavonoids/pharmacology , Cytokines/metabolism , Disease Models, Animal , Collagen/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Liver
8.
J Med Chem ; 66(23): 15847-15866, 2023 12 14.
Article in English | MEDLINE | ID: mdl-37983615

ABSTRACT

The orphan nuclear receptor Nur77 has been validated as a potential drug target for treating breast cancer. Therefore, focusing on the SAR study of the lead 8b (KDSPR(Nur77) = 354 nM), we found the active compound ja which exhibited improved Nur77-binding capability (KDSPR(Nur77) = 91 nM) and excellent antiproliferative activities against breast cancer cell lines. Interestingly, ja acted as a potent and selective Nur77 antagonist, displaying good potency against triple-negative breast cancer (TNBC) cell lines but did not inhibit human normal breast cancer cell line MCF-10A (SI > 20). Exceptionally, ja Nur77-dependently caused mitochondria dysfunction and induced the caspase-dependent apoptosis by mediating the TP53 phosphorylation pathway. Moreover, ja significantly suppressed MDA-MB-231 xenograft tumor growth but had no apparent side effects in mice and zebrafish. Overall, ja demonstrated to be the first Nur77 modulator mediating the TP53 phosphorylation pathway that has the potential as a novel anticancer agent for TNBC.


Subject(s)
Antineoplastic Agents , Triple Negative Breast Neoplasms , Humans , Animals , Mice , Triple Negative Breast Neoplasms/pathology , Cell Line, Tumor , Zebrafish , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/chemistry , Apoptosis , Indoles/chemistry , Cell Proliferation
9.
Molecules ; 28(19)2023 Oct 03.
Article in English | MEDLINE | ID: mdl-37836760

ABSTRACT

In this paper, liquid-liquid chromatography was introduced for the first time for the separation of fingered citron (Citrus medica L. var. sarcodactylis Swingle). The fingered citron cultivated in Jinhua is of significant industrial and medicinal value, with several major coumarin compounds detected in its extract. Therefore, further separation for higher purity was of necessity. A preparative liquid-liquid chromatographic method was developed by combining two elution modes (isocratic and step-gradient) with selection according to different polarities of the target sample. Five coumarin derivatives-5,7-dimethoxycoumarin (52.6 mg, 99.6%), phellopterin (4.9 mg, 97.1%), 5-prenyloxy-7-methoxycoumarin (6.7 mg, 98.7%), 6-hydroxy-7-methoxycoumarin (7.1 mg, 82.2%), and byakangelicol (10.5 mg, 90.1%)-with similar structures and properties were isolated on a large scale from 100 mg of petroleum ether (PE) extract and 100 mg of ethyl acetate (EA) extract in Jinhua fingered citron. The productivity was much improved. The anti-growth activity of the isolated coumarins was evaluated against three cancer cell lines (HeLa, A549, and MCF7) with an MTT assay. The coumarins demonstrated potential anti-tumor activity on the HeLa cell line, with 5,7-dimethoxycoumarin in particular exhibiting the best anti-growth activity (IC50 = 10.57 ± 0.24 µM) by inhibiting proliferation. It inhibited colony formation and reduced the size of the tumor sphere in a concentration-dependent manner. The main mechanism was confirmed as inducing apoptosis. This work was informative for further studies aimed at exploring new natural-product-based antitumor agents.


Subject(s)
Citrus , Plant Extracts , Humans , HeLa Cells , Plant Extracts/pharmacology , Plant Extracts/chemistry , Coumarins/pharmacology , Citrus/chemistry , Chromatography, Liquid
10.
Bioorg Chem ; 140: 106795, 2023 11.
Article in English | MEDLINE | ID: mdl-37657195

ABSTRACT

Hepatic fibrosis remains a great challenge clinically. The orphan nuclear receptor Nur77 is recently suggested as the critical regulator of transforming growth factor-ß (TGF-ß) signaling, which plays a central role in multi-organic fibrosis. Herein, we optimized our previously reported Nur77-targeted compound 9 h for attempting to develop effective and safe anti-hepatic fibrosis agents. The critical pharmacophore scaffold of pyridine-carbonyl-hydrazine-1-carboxamide was retained, while the naphthalene ring was replaced with an aromatic ring containing pyridyl or indole groups. Four series of derivatives were thus generated, among which the compound 16f had excellent binding activity toward Nur77-LBD (KD = 470 nM) with the best inhibitory activity against the TGF- ß 1 activation of hepatic stellate cells (HSCs) and low cytotoxicity to normal mice liver AML-12 cells (IC50 > 80 µM). In mice, 16f displayed potent activity against CCl4-induced liver fibrosis with improved liver function. Mechanistically, 16f-mediated inactivation of HSC and suppression of liver fibrosis were associated with its enhancement of autophagic flux in a Nur77-dependent manner. Together, 16f was identified as a potential anti-liver fibrosis agent. Our study suggests that Nur77 may serve as a critical anti-hepatic fibrosis target.


Subject(s)
Anticonvulsants , Liver Cirrhosis , Animals , Mice , Liver Cirrhosis/chemically induced , Liver Cirrhosis/drug therapy , Antifibrotic Agents , Autophagy , Hepatic Stellate Cells
11.
Med Image Anal ; 89: 102845, 2023 10.
Article in English | MEDLINE | ID: mdl-37597317

ABSTRACT

Self-supervised representation learning (SSL) has achieved remarkable success in its application to natural images while falling behind in performance when applied to whole-slide pathological images (WSIs). This is because the inherent characteristics of WSIs in terms of gigapixel resolution and multiple objects in training patches are fundamentally different from natural images. Directly transferring the state-of-the-art (SOTA) SSL methods designed for natural images to WSIs will inevitably compromise their performance. We present a novel scheme SGCL: Spatial Guided Contrastive Learning, to fully explore the inherent properties of WSIs, leveraging the spatial proximity and multi-object priors for stable self-supervision. Beyond the self-invariance of instance discrimination, we expand and propagate the spatial proximity for the intra-invariance from the same WSI and inter-invariance from different WSIs, as well as propose the spatial-guided multi-cropping for inner-invariance within patches. To adaptively explore such spatial information without supervision, we propose a new loss function and conduct a theoretical analysis to validate it. This novel scheme of SGCL is able to achieve additional improvements over the SOTA pre-training methods on diverse downstream tasks across multiple datasets. Extensive ablation studies have been carried out and visualizations of these results have been presented to aid understanding of the proposed SGCL scheme. As open science, all codes and pre-trained models are available at https://github.com/HHHedo/SGCL.


Subject(s)
Image Interpretation, Computer-Assisted , Machine Learning , Pathology, Clinical , Pathology, Clinical/methods
12.
ACS Chem Biol ; 18(7): 1632-1641, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37427444

ABSTRACT

Glycosaminoglycan synthases have immense potential in applications involving synthesis of oligosaccharides, using enzymatic approaches and construction of cell factories that produce polysaccharides as critical metabolic components. However, the use of high-throughput activity assays to screen for the evolution of these enzymes can be challenging because there are no significant changes in fluorescence or absorbance associated with glycosidic bond formation. Here, using incorporation of azido-labeled N-acetylhexosamine analogs into bacterial capsule polysaccharides via bacterial metabolism and bioorthogonal chemistry, fluorophores were specifically introduced onto cell surfaces. Furthermore, correlations between detectable fluorescence signals and the polysaccharide-synthesizing capacity of individual bacteria were established. Among 10 candidate genes, 6 members of the chondroitin synthase family were quickly identified in a recombinant Bacillus subtilis host strain. Additionally, directed evolution of heparosan synthase was successfully performed using fluorescence-activated cell sorting of recombinant Escherichia coli O10:K5(L):H4, yielding several mutants with increased activity. Cell-based approaches that selectively detect the presence or absence of synthases within an individual colony of bacterial cells, as well as their level of activity, have broad potential in the exploration and engineering of glycosaminoglycan synthases. These approaches also support the creation of novel strategies for high-throughput screening of enzyme activity based on cell systems.


Subject(s)
Glycosaminoglycans , Metabolic Engineering , High-Throughput Screening Assays , Escherichia coli , Bacteria/genetics , Polysaccharides, Bacterial
13.
J Biol Chem ; 299(8): 105019, 2023 08.
Article in English | MEDLINE | ID: mdl-37422193

ABSTRACT

Poly(A)-binding protein nuclear 1 (PABPN1) is an RNA-binding protein localized in nuclear speckles, while its alanine (Ala)-expanded variants accumulate as intranuclear aggregates in oculopharyngeal muscular dystrophy. The factors that drive PABPN1 aggregation and its cellular consequences remain largely unknown. Here, we investigated the roles of Ala stretch and poly(A) RNA in the phase transition of PABPN1 using biochemical and molecular cell biology methods. We have revealed that the Ala stretch controls its mobility in nuclear speckles, and Ala expansion leads to aggregation from the dynamic speckles. Poly(A) nucleotide is essential to the early-stage condensation that thereby facilitates speckle formation and transition to solid-like aggregates. Moreover, the PABPN1 aggregates can sequester CFIm25, a component of the pre-mRNA 3'-UTR processing complex, in an mRNA-dependent manner and consequently impair the function of CFIm25 in alternative polyadenylation. In conclusion, our study elucidates a molecular mechanism underlying PABPN1 aggregation and sequestration, which will be beneficial for understanding PABPN1 proteinopathy.


Subject(s)
Muscular Dystrophy, Oculopharyngeal , Polyadenylation , Humans , Alanine/metabolism , Muscular Dystrophy, Oculopharyngeal/genetics , Muscular Dystrophy, Oculopharyngeal/metabolism , Poly(A)-Binding Protein I/genetics , Poly(A)-Binding Protein I/metabolism , RNA/metabolism
14.
Chin Med J (Engl) ; 136(18): 2195-2202, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37279378

ABSTRACT

BACKGROUND: The relationship between the elevation of cardiac troponin and the increase of mortality and hospitalization rate in patients with heart failure with reduced ejection fraction is clear. This study investigated the association between the extent of elevated levels of high-sensitivity cardiac troponin I (hs-cTnI) and the prognosis in heart failure with preserved ejection fraction patients. METHODS: A retrospective cohort study consecutively enrolled 470 patients with heart failure with preserved ejection fraction from September 2014 to August 2017. According to the level of hs-cTnI, the patients were divided into the elevated level group (hs-cTnI >0.034 ng/mL in male and hs-cTnI >0.016 ng/mL in female) and the normal level group. All of the patients were followed up once every 6 months. Adverse cardiovascular events were cardiogenic death and heart failure hospitalization. RESULTS: The mean follow-up period was 36.2 ± 7.9 months. Cardiogenic mortality (18.6% [26/140] vs. 1.5% [5/330], P <0.001) and heart failure (HF) hospitalization rate (74.3% [104/140] vs. 43.6% [144/330], P <0.001) were significantly higher in the elevated level group. The Cox regression analysis showed that the elevated level of hs-cTnI was a predictor of cardiogenic death (hazard ratio [HR]: 5.578, 95% confidence interval [CI]: 2.995-10.386, P <0.001) and HF hospitalization (HR: 3.254, 95% CI: 2.698-3.923, P <0.001). The receiver operating characteristic curve demonstrated that a sensitivity of 72.6% and specificity of 88.8% for correct prediction of adverse cardiovascular events when a level of hs-cTnI of 0.1305 ng/mL in male and a sensitivity of 70.6% and specificity of 90.2% when a level of hs-cTnI of 0.0755 ng/mL in female were used as the cut-off value. CONCLUSION: Significant elevation of hs-cTnI (≥0.1305 ng/mL in male and ≥0.0755 ng/mL in female) is an effective indicator of the increased risk of cardiogenic death and HF hospitalization in heart failure with preserved ejection fraction patients.


Subject(s)
Heart Failure , Troponin I , Humans , Male , Female , Stroke Volume , Retrospective Studies , Biomarkers , Prognosis
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 299: 122840, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37196554

ABSTRACT

In this work, through the orthogonal design of two fluorophores and two recognition groups, a series of fluorescent probes were developed from the flavone derivatives for hydrogen sulfide (H2S). The probe FlaN-DN stood out from the primarily screening on the selectivity and response intensities. It could respond to H2S with both the chromogenic and fluorescent signals. Among the recent reported probes for the H2S detection, FlaN-DN indicated the most highlighted advantages including the rapid response (within 200 s) and the high response multiplication (over 100 folds). FlaN-DN was sensitive to the pH condition, thus could be applied to distinguish the cancer micro-environment. Moreover, FlaN-DN suggested practical capabilities including a wide linear range (0-400 µM), a relatively high sensitivity (limit of detection 0.13 µM), and high selectivity towards H2S. As a low cytotoxic probe, FlaN-DN achieved the imaging in living HeLa cells. FlaN-DN could detect the endogenous generation H2S and visualize the dose-dependent responses to the exogenous H2S level. This work provided a typical case of natural-sourced derivatives as functional implements, which might inspire the future investigations.


Subject(s)
Flavones , Hydrogen Sulfide , Humans , HeLa Cells , Fluorescent Dyes , Microscopy, Fluorescence/methods
16.
Acta Biochim Biophys Sin (Shanghai) ; 55(5): 736-748, 2023 May 11.
Article in English | MEDLINE | ID: mdl-37171184

ABSTRACT

Nine polyglutamine (polyQ) proteins have already been identified that are considered to be associated with the pathologies of neurodegenerative disorders called polyQ diseases, but whether these polyQ proteins mutually interact and synergize in proteinopathies remains to be elucidated. In this study, 4 polyQ-containing proteins, androgen receptor (AR), ataxin-7 (Atx7), huntingtin (Htt) and ataxin-3 (Atx3), are used as model molecules to investigate their heterologous coaggregation and consequent impact on cellular proteostasis. Our data indicate that the N-terminal fragment of polyQ-expanded (PQE) Atx7 or Htt can coaggregate with and sequester AR and Atx3 into insoluble aggregates or inclusions through their respective polyQ tracts. In vitro coprecipitation and NMR titration experiments suggest that this specific coaggregation depends on polyQ lengths and is probably mediated by polyQ-tract interactions. Luciferase reporter assay shows that these coaggregation and sequestration effects can deplete the cellular availability of AR and consequently impair its transactivation function. This study provides valid evidence supporting the viewpoint that coaggregation of polyQ proteins is mediated by polyQ-tract interactions and benefits our understanding of the molecular mechanism underlying the accumulation of different polyQ proteins in inclusions and their copathological causes of polyQ diseases.


Subject(s)
Neurodegenerative Diseases , Proteostasis , Humans , Peptides/chemistry , Huntingtin Protein/genetics , Huntingtin Protein/metabolism , Ataxin-3/genetics , Ataxin-3/metabolism
17.
Front Bioeng Biotechnol ; 11: 1153265, 2023.
Article in English | MEDLINE | ID: mdl-37077231

ABSTRACT

Objective: Autonomous vehicles (Avs) have paved the way for the arrangement of swivel seats in vehicles, which could pose a challenge to traditional safety systems. The integration of automated emergency braking (AEB) and pre-pretension (PPT) seatbelts improves protection for a vehicle's occupant. The objective of this study is to explore the control strategies of an integrated safety system for swiveled seating orientations. Methods: Occupant restraints were examined in various seating configurations using a single-seat model with a seat-mounted seatbelt. Seat orientation was set at different angles, from -45° to 45° with 15° increments. A pretension was used on the shoulder belt to represent an active belt force cooperating with AEB. A generic full frontal vehicle pulse of 20 mph was applied to the sled. The occupant's kinematics response under various integrated safety system control strategies was analyzed by extracting a head pre-crash kinematics envelope. The injury values were calculated for various seating directions with or without an integrated safety system at the collision speed of 20 mph. Results: In a lateral movement, the excursions of the dummy head were 100 mm and 70 mm in the global coordinate system for negative and positive seat orientations, respectively. In the axial movement, the head traveled 150 mm and 180 mm in the global coordinate system for positive and negative seating directions, respectively. The 3-point seatbelt did not restrain the occupant symmetrically. The occupant experienced greater y-axis excursion and smaller x-axis excursion in the negative seat position. Various integrated safety system control strategies led to significant differences in head movement in the y direction. The integrated safety system reduced the occupant's potential injury risks in different seating positions. When the AEB and PPT were activated, the absolute HIC15, brain injury criteria (BrIC), neck injury (Nij), and chest deflection were reduced in most seating directions. However, the pre-crash increased the injury risks at some seating positions. Conclusion: The pre-pretension seatbelt could reduce the occupant's forward movement in the rotating seat positions in a pre-crash period. The occupant's pre-crash motion envelope was generated, which could be beneficial to future restraint systems and vehicle interior design. The integrated safety system could reduce injuries in different seating orientations.

18.
J Gastrointest Oncol ; 14(1): 420-428, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36915423

ABSTRACT

Background: We aimed to identify cancer pain genes in pancreatic ductal adenocarcinoma (PDAC) using bioinformatic tools to provide evidence for pain treatment in PDAC patients. Methods: The GSE50570 data were obtained from the high-throughput Gene Expression Omnibus (GEO) database and subsequently analyzed. A volcano map, principal component analysis (PCA) map, box plot, and heat map were drawn, and a Venn diagram was constructed by comparison with human secreted histone genes. The differentially expressed secreted histone genes in PDAC were obtained. Then, Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed, followed by protein-protein interaction (PPI) network analysis and key genetic screening. Results: In comparison to normal samples, the expression of 81 secreted protein-related genes was downregulated, and the expression of 12 secreted protein-related genes was upregulated in PDAC. According to the GO and KEGG enrichment analysis results, these differentially expressed genes are mainly involved in the PI3K-Akt signaling pathway, protein digestion and absorption, extracellular matrix (ECM) receptor interaction, AGE-RAGE (advanced glycation endproducts-the Receptor of Advanced Glycation Endproducts) signaling pathway, relaxin signaling pathway, interleukin-17 (IL-17) signaling pathway, and transforming growth factor-ß (TGF-ß) signaling pathway, affecting the different manifestations of PDAC cancer pain. We used Cytoscape software to construct a protein interaction network of common differentially expressed genes and obtained three clusters with high scores. Our literature review found that several genes, including PTGS2, VCAN, and CCL2, were directly related to cancer pain occurrence. Conclusions: By data mining the PDAC tumor expression, dozens of differentially expressed genes were identified in this study, several of which have been associated with the frequency and severity of cancer pain. This study provides an important foundation for the pain treatment of PDAC tumor patients.

19.
Molecules ; 28(3)2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36770611

ABSTRACT

Kinases are among the most important families of biomolecules and play an essential role in the regulation of cell proliferation, apoptosis, metabolism, and other critical physiological processes. The dysregulation and gene mutation of kinases are linked to the occurrence and development of various human diseases, especially cancer. As a result, a growing number of small-molecule drugs based on kinase targets are being successfully developed and approved for the treatment of many diseases. The indole/azaindole/oxindole moieties are important key pharmacophores of many bioactive compounds and are generally used as excellent scaffolds for drug discovery in medicinal chemistry. To date, 30 ATP-competitive kinase inhibitors bearing the indole/azaindole/oxindole scaffold have been approved for the treatment of diseases. Herein, we summarize their research and development (R&D) process and describe their binding models to the ATP-binding sites of the target kinases. Moreover, we discuss the significant role of the indole/azaindole/oxindole skeletons in the interaction of their parent drug and target kinases, providing new medicinal chemistry inspiration and ideas for the subsequent development and optimization of kinase inhibitors.


Subject(s)
Drug Discovery , Protein Kinase Inhibitors , Humans , Oxindoles/pharmacology , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemistry , Binding Sites , Adenosine Triphosphate/metabolism
20.
Sci Adv ; 9(7): eade4770, 2023 02 17.
Article in English | MEDLINE | ID: mdl-36800421

ABSTRACT

The introduction of unnatural chemical moieties into glycosaminoglycans (GAGs) has enormous potential to facilitate studies of the mechanism and application of these critical, widespread molecules. Unnatural N-acetylhexosamine analogs were metabolically incorporated into the capsule polysaccharides of Escherichia coli and Bacillus subtilis via bacterial metabolism. Targeted metabolic labeled hyaluronan and the precursors of heparin and chondroitin sulfate were obtained. The azido-labeled polysaccharides (purified or in capsules) were reacted with dyes, via bioorthogonal chemistry, to enable detection and imaging. Site-specific introduction of fluorophores directly onto cell surfaces affords another choice for observing and quantifying bacteria in vivo and in vitro. Furthermore, azido-polysaccharides retain similar biological properties to their natural analogs, and reliable and predictable introduction of functionalities, such as fluorophores, onto azido-N-hexosamines in the disaccharide repeat units provides chemical tools for imaging and metabolic analysis of GAGs in vivo and in vitro.


Subject(s)
Escherichia coli , Glycosaminoglycans , Glycosaminoglycans/chemistry , Escherichia coli/metabolism , Polysaccharides , Heparin , Chondroitin Sulfates , Polysaccharides, Bacterial
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