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1.
Int J Ophthalmol ; 17(3): 485-490, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721517

RESUMO

AIM: To investigate the long-term changes of corneal densitometry (CD) and its contributing elements after small incision lenticule extraction (SMILE). METHODS: Totally 31 eyes of 31 patients with mean spherical equivalent of -6.46±1.50 D and mean age 28.23±7.38y were enrolled. Full-scale examinations were conducted on all patients preoperatively and during follow-up. Visual acuity, manifest refraction, axial length, corneal thickness, corneal higher-order aberrations, and CD were evaluated. RESULTS: All surgeries were completed successfully without complications or adverse events. Ten-year safety index was 1.17±0.20 and efficacy 1.04±0.28. CD value of 0-6 mm zones in central layer was statistically significantly lower 10y postoperatively, compared with preoperative values (0-2 mmΔ=-1.62, 2-6 mmΔ=-1.24, P<0.01). There were no correlations between CD values and factors evaluated. CONCLUSION: SMILE is a safe and efficient procedure for myopia on a long-term basis. CD values get lower 10y postoperatively, whose mechanism is to be further discussed.

2.
Immunol Res ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722530

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial hyperplasia, pannus formation, and cartilage and bone destruction. Lysine-specific demethylase 1 (LSD1), an enzyme involved in transcriptional regulation, has an unclear role in synovial inflammation, fibroblast-like synoviocytes migration, and invasion during RA pathogenesis. In this study, we observed increased LSD1 expression in RA synovial tissues and in TNF-α-stimulated MH7A cells. SP2509, an LSD1 antagonist, directly reduced LSD1 expression and reversed the elevated levels of proteins associated with inflammation, apoptosis, proliferation, and autophagy induced by TNF-α. Furthermore, SP2509 inhibited the migratory capacity of MH7A cells, which was enhanced by TNF-α. In CIA models, SP2509 treatment ameliorated RA development, reducing the expression of pro-inflammatory cytokines and alleviating joint pathological symptoms. These findings underscore the significance of LSD1 in RA and propose the therapeutic potential of SP2509.

3.
Phytomedicine ; 129: 155657, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38692076

RESUMO

BACKGROUND: The pentose phosphate pathway (PPP) plays a crucial role in the material and energy metabolism in cancer cells. Targeting 6-phosphogluconate dehydrogenase (6PGD), the rate-limiting enzyme in the PPP metabolic process, to inhibit cellular metabolism is an effective anticancer strategy. In our previous study, we have preliminarily demonstrated that gambogic acid (GA) induced cancer cell death by inhibiting 6PGD and suppressing PPP at the cellular level. However, it is unclear whether GA could suppress cancer cell growth by inhibiting PPP pathway in mouse model. PURPOSE: This study aimed to confirm that GA as a covalent inhibitor of 6PGD protein and to validate that GA suppresses cancer cell growth by inhibiting the PPP pathway in a mouse model. METHODS: Cell viability was detected by CCK-8 assays as well as flow cytometry. The protein targets of GA were identified using a chemical probe and activity-based protein profiling (ABPP) technology. The target validation was performed by in-gel fluorescence assay, the Cellular Thermal Shift Assay (CETSA). A lung cancer mouse model was constructed to test the anticancer activity of GA. RNA sequencing was performed to analyze the global effect of GA on gene expression. RESULTS: The chemical probe of GA exhibited high biological activity in vitro. 6PGD was identified as one of the binding proteins of GA by ABPP. Our findings revealed a direct interaction between GA and 6PGD. We also found that the anti-cancer activity of GA depended on reactive oxygen species (ROS), as evidenced by experiments on cells with 6PGD knocked down. More importantly, GA could effectively reduce the production of the two major metabolites of the PPP in lung tissue and inhibit cancer cell growth in the mouse model. Finally, RNA sequencing data suggested that GA treatment significantly regulated apoptosis and hypoxia-related physiological processes. CONCLUSION: These results demonstrated that GA was a covalent inhibitor of 6PGD protein. GA effectively suppressed cancer cell growth by inhibiting the PPP pathway without causing significant side effects in the mouse model. Our study provides in vivo evidence that elucidates the anticancer mechanism of GA, which involves the inhibition of 6PGD and modulation of cellular metabolic processes.

4.
Adv Sci (Weinh) ; : e2310263, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647431

RESUMO

Metal halide perovskites (MHPs) are considered as promising candidates in the application of nonvolatile high-density, low-cost resistive switching (RS) memories and artificial synapses, resulting from their excellent electronic and optoelectronic properties including large light absorption coefficient, fast ion migration, long carrier diffusion length, low trap density, high defect tolerance. Among MHPs, 2D halide perovskites have exotic layered structure and great environment stability as compared with 3D counterparts. Herein, recent advances of 2D MHPs for the RS memories and artificial synapses realms are comprehensively summarized and discussed, as well as the layered structure properties and the related physical mechanisms are presented. Furthermore, the current issues and developing roadmap for the next-generation 2D MHPs RS memories and artificial synapse are elucidated.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38613651

RESUMO

PURPOSE: Zygotes with 2.1 pronuclei (2.1PN) present with two normal-sized pronuclei, and an additional smaller pronucleus, that is approximately smaller than two thirds the size of a normal pronucleus. It remains unclear whether the additional pronucleus causes embryonic chromosome abnormalities. In the majority of cases, in vitro fertilization (IVF) clinics discarded 2.1PN zygotes. Thus, the present study aimed to evaluate the developmental potential and value of 2.1PN zygotes. METHODS: 2.1PN-derived embryos from 164 patients who underwent IVF or intracytoplasmic sperm injection (ICSI) treatment between January 2021 and December 2022 were included in the present study. All embryos were monitored using a time-lapse system, and blastocyst formation was used to assess 2.1PN-derived embryo developmental potential. The blastocyst formation was quantified using generalized estimating equations, and chromosome euploidy was analyzed using next-generation sequencing (NGS). In addition, the potential association between age and occurrence of 2.1PN zygotes was determined. RESULTS: The present study demonstrated that numerous 2.1PN zygotes developed into blastocysts. Early cleavage patterns and embryo quality on Day 3 were the independent predictors for the blastocyst formation of 2.1PN-derived embryos. The 2.1PN zygotes displayed a comparable developmental potential compared to 2PN zygotes in advanced age patients (≥ 38). Moreover, there was a tendency that 2.1PN-derived blastocysts showed a similar euploidy rate compared to 2PN-derived blastocysts. CONCLUSION: Clinicians should consider using 2.1PN-derived euploid embryos for transfer after preimplantation genetic testing in the absence of available 2PN embryo cycles. 2.1PN-derived embryos could be a candidate, particularly beneficial for patients at advanced age.

6.
Discov Med ; 36(183): 753-764, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38665024

RESUMO

BACKGROUND: Dental fluorosis is a discoloration of the teeth caused by the excessive consumption of fluoride. It represents a distinct manifestation of chronic fluorosis in dental tissues, exerting adverse effects on the human body, particularly on teeth. The transmembrane protein 16a (TMEM16A) is expressed at the junction of the endoplasmic reticulum and the plasma membrane. Alterations in its channel activity can disrupt endoplasmic reticulum calcium homeostasis and intracellular calcium ion concentration, thereby inducing endoplasmic reticulum stress (ERS). This study aims to investigate the influence of calcium supplements and TMEM16A on ERS in dental fluorosis. METHODS: C57BL/6 mice exhibiting dental fluorosis were subjected to an eight-week treatment with varying calcium concentrations: low (0.071%), medium (0.79%), and high (6.61%). Various assays, including Hematoxylin and Eosin (HE) staining, immunohistochemistry, real-time fluorescence quantitative polymerase chain reaction (qPCR), and Western blot, were employed to assess the impact of calcium supplements on fluoride content, ameloblast morphology, TMEM16A expression, and endoplasmic reticulum stress-related proteins (calreticulin (CRT), glucose-regulated protein 78 (GRP78), inositol requiring kinase 1α (IRE1α), PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6)) in the incisors of mice affected by dental fluorosis. Furthermore, mice with dental fluorosis were treated with the TMEM16A inhibitor T16Ainh-A01 along with a medium-dose calcium to investigate the influence of TMEM16A on fluoride content, ameloblast morphology, and endoplasmic reticulum stress-related proteins in the context of mouse incisor fluorosis. RESULTS: In comparison to the model mice, the fluoride content in incisors significantly decreased following calcium supplements (p < 0.01). Moreover, the expression of TMEM16A, CRT, GRP78, IRE1α, PERK, and ATF6 were also exhibited a substantial reduction (p < 0.01), with the most pronounced effect observed in the medium-dose calcium group. Additionally, the fluoride content (p < 0.05) and the expression of CRT, GRP78, IRE1α, PERK, and ATF6 (p < 0.01) were further diminished following concurrent treatment with the TMEM16A inhibitor T16Ainh-A01 and a medium dose of calcium. CONCLUSIONS: The supplementation of calcium or the inhibition of TMEM16A expression appears to mitigate the detrimental effects of fluorosis by suppressing endoplasmic reticulum stress. These findings hold implications for identifying potential therapeutic targets in addressing dental fluorosis.


Assuntos
Cálcio , Suplementos Nutricionais , Fluorose Dentária , Animais , Masculino , Camundongos , Fator 6 Ativador da Transcrição/metabolismo , Adenina/análogos & derivados , Ameloblastos/metabolismo , Ameloblastos/patologia , Ameloblastos/efeitos dos fármacos , Anoctamina-1/metabolismo , Anoctamina-1/antagonistas & inibidores , Anoctamina-1/genética , Cálcio/metabolismo , Modelos Animais de Doenças , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endorribonucleases/metabolismo , Fluoretos/toxicidade , Fluoretos/efeitos adversos , Fluorose Dentária/patologia , Fluorose Dentária/metabolismo , Fluorose Dentária/etiologia , Indóis , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores
7.
J Med Chem ; 67(9): 7283-7300, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38676656

RESUMO

The epidermal growth factor receptor (EGFR) tertiary C797S mutation is an important cause of resistance to Osimertinib, which seriously hinders the clinical application of Osimertinib. Developing proteolysis-targeting chimeras (PROTACs) targeting EGFR mutants can offer a promising strategy to overcome drug resistance. In this study, some novel PROTACs targeting C797S mutation were designed and synthesized based on a new EGFR inhibitor and displayed a potent degradation effect in H1975-TM cells harboring EGFRL858R/T790M/C797S. The representative compound C6 exhibited a DC50 of 10.2 nM against EGFRL858R/T790M/C797S and an IC50 of 10.3 nM against H1975-TM. Furthermore, C6 also showed potent degradation activity against various main EGFR mutants, including EGFRDel19/T790M/C797S. Mechanistic studies revealed that the protein degradation was achieved through the ubiquitin-proteasome system. Finally, C6 inhibited tumor growth in the H1975-TM xenograft tumor model effectively and safely. This study identifies a novel and potent EGFR PROTAC to overcome Osimertinib resistance mediated by C797S mutation.


Assuntos
Antineoplásicos , Desenho de Fármacos , Receptores ErbB , Mutação , Inibidores de Proteínas Quinases , Proteólise , Receptores ErbB/metabolismo , Receptores ErbB/genética , Receptores ErbB/antagonistas & inibidores , Humanos , Animais , Proteólise/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Camundongos Nus , Acrilamidas/farmacologia , Acrilamidas/síntese química , Acrilamidas/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Compostos de Anilina/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/química , Camundongos Endogâmicos BALB C , Relação Estrutura-Atividade , Quimera de Direcionamento de Proteólise , Indóis , Pirimidinas
8.
ArXiv ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38562443

RESUMO

The intricate nature of the brain necessitates the application of advanced probing techniques to comprehensively study and understand its working mechanisms. Neurophotonics offers minimally invasive methods to probe the brain using optics at cellular and even molecular levels. However, multiple challenges persist, especially concerning imaging depth, field of view, speed, and biocompatibility. A major hindrance to solving these challenges in optics is the scattering nature of the brain. This perspective highlights the potential of complex media optics, a specialized area of study focused on light propagation in materials with intricate heterogeneous optical properties, in advancing and improving neuronal readouts for structural imaging and optical recordings of neuronal activity. Key strategies include wavefront shaping techniques and computational imaging and sensing techniques that exploit scattering properties for enhanced performance. We discuss the potential merger of the two fields as well as potential challenges and perspectives toward longer term in vivo applications.

9.
Neurophotonics ; 11(Suppl 1): S11510, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38617592

RESUMO

The intricate nature of the brain necessitates the application of advanced probing techniques to comprehensively study and understand its working mechanisms. Neurophotonics offers minimally invasive methods to probe the brain using optics at cellular and even molecular levels. However, multiple challenges persist, especially concerning imaging depth, field of view, speed, and biocompatibility. A major hindrance to solving these challenges in optics is the scattering nature of the brain. This perspective highlights the potential of complex media optics, a specialized area of study focused on light propagation in materials with intricate heterogeneous optical properties, in advancing and improving neuronal readouts for structural imaging and optical recordings of neuronal activity. Key strategies include wavefront shaping techniques and computational imaging and sensing techniques that exploit scattering properties for enhanced performance. We discuss the potential merger of the two fields as well as potential challenges and perspectives toward longer term in vivo applications.

10.
Emerg Microbes Infect ; 13(1): 2332669, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38494777

RESUMO

Generating an infectious non-human primate (NHP) model using a prevalent monkeypox virus (MPXV) strain has emerged as a crucial strategy for assessing the efficacy of vaccines and antiviral drugs against human MPXV infection. Here, we established an animal model by infecting cynomolgus macaques with the prevalent MPXV strain, WIBP-MPXV-001, and simulating its natural routes of infection. A comprehensive analysis and evaluation were conducted on three animals, including monitoring clinical symptoms, collecting hematology data, measuring viral loads, evaluating cellular and humoral immune responses, and examining histopathology. Our findings revealed that initial skin lesions appeared at the inoculation sites and subsequently spread to the limbs and back, and all infected animals exhibited bilateral inguinal lymphadenopathy, eventually leading to a self-limiting disease course. Viral DNA was detected in post-infection blood, nasal, throat, rectal and blister fluid swabs. These observations indicate that the NHP model accurately reflects critical clinical features observed in human MPXV infection. Notably, the animals displayed clinical symptoms and disease progression similar to those of humans, rather than a lethal outcome as observed in previous studies. Historically, MPXV was utilized as a surrogate model for smallpox. However, our study contributes to a better understanding of the dynamics of current MPXV infections while providing a potential infectious NHP model for further evaluation of vaccines and antiviral drugs against mpox infection. Furthermore, the challenge model closely mimics the primary natural routes of transmission for human MPXV infections. This approach enhances our understanding of the precise mechanisms underlying the interhuman transmission of MPXV.


Assuntos
Mpox , Vacinas , Animais , Humanos , Monkeypox virus/genética , Antivirais/farmacologia , Macaca
11.
J Med Virol ; 96(3): e29531, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38515377

RESUMO

The Nucleocapsid Protein (NP) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not only the core structural protein required for viral packaging, but also participates in the regulation of viral replication, and its post-translational modifications such as phosphorylation have been shown to be an important strategy for regulating virus proliferation. Our previous work identified NP could be ubiquitinated, as confirmed by two independent studies. But the function of NP ubiquitination is currently unknown. In this study, we first pinpointed TRIM6 as the E3 ubiquitin ligase responsible for NP ubiquitination, binding to NP's CTD via its RING and B-box-CCD domains. TRIM6 promotes the K29-typed polyubiquitination of NP at K102, K347, and K361 residues, increasing its binding to viral genomic RNA. Consistently, functional experiments such as the use of the reverse genetic tool trVLP model and gene knockout of TRIM6 further confirmed that blocking the ubiquitination of NP by TRIM6 significantly inhibited the proliferation of SARS-CoV-2. Notably, the NP of coronavirus is relatively conserved, and the NP of SARS-CoV can also be ubiquitinated by TRIM6, indicating that NP could be a broad-spectrum anti-coronavirus target. These findings shed light on the intricate interaction between SARS-CoV-2 and the host, potentially opening new opportunities for COVID-19 therapeutic development.


Assuntos
COVID-19 , Genoma Viral , SARS-CoV-2 , Ubiquitina-Proteína Ligases , Humanos , Proliferação de Células , COVID-19/genética , COVID-19/virologia , Proteínas do Nucleocapsídeo/genética , RNA Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo
12.
Chem Sci ; 15(12): 4313-4321, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516082

RESUMO

Identifying the cellular targets of bioactive small molecules within tissues has been a major concern in drug discovery and chemical biology research. Compared to cell line models, tissues consist of multiple cell types and complicated microenvironments. Therefore, elucidating the distribution and heterogeneity of targets across various cells in tissues would enhance the mechanistic understanding of drug or toxin action in real-life scenarios. Here, we present a novel multi-omics integration pipeline called Single-cell TargEt Profiling (STEP) that enables the global profiling of protein targets in mammalian tissues with single-cell resolution. This pipeline integrates single-cell transcriptome datasets with tissue-level protein target profiling using chemoproteomics. Taking well-established classic drugs such as aspirin, aristolochic acid, and cisplatin as examples, we confirmed the specificity and precision of cellular drug-target profiles and their associated molecular pathways in tissues using the STEP analysis. Our findings provide more informative insights into the action modes of bioactive molecules compared to in vitro models. Collectively, STEP represents a novel strategy for profiling cellular-specific targets and functional processes with unprecedented resolution.

13.
Cont Lens Anterior Eye ; 47(2): 102127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350814

RESUMO

PURPOSE: The aim of this study was to evaluate the long-term effects of serial intravitreal injections (IVI) on measures of dry eye. METHODS: The PubMed, EMBASE, and Cochrane databases were searched according to the PROSPERO protocol (CRD42023455727). Studies evaluating the influence of serial IVI on the ocular surface compared with untreated fellow eyes were included. The measures of dry eye after IVI were used as outcome variables. The results are presented as mean difference (MD) with a corresponding 95% confidence interval (CI). RESULTS: A total of 4 studies with 259 participants were included in this meta-analysis. Significant increases in ocular surface disease index (OSDI) scores (MD 10.26, 95 % CI 5.05 to 15.46, p < 0.01) and tear film osmolarity (TOsm; MD 4.40, 95 % CI 0.87 to 7.92, p = 0.01) were observed in the IVI treated eyes compared to the untreated fellow eyes. There was no significant difference between the groups with respect to fluorescein tear film break-up time (TBUT; p = 0.05), average non-invasive tear film break-up time (NITBUT; p = 0.94), first NITBUT (p = 0.78) and Schirmer test (p = 0.94). CONCLUSION: Repeated IVI of anti-VEGF agents with preoperative povidone-iodine application was associated with increased OSDI scores and TOsm, while no significant difference was found in fluorescein TBUT, average NITBUT, first NITBUT and Schirmer test. The ocular surface may partially recover after the procedures, but IVI still has deleterious effects on the ocular surface.


Assuntos
Síndromes do Olho Seco , Humanos , Injeções Intravítreas , Síndromes do Olho Seco/tratamento farmacológico , Povidona-Iodo , Lágrimas , Fluoresceína
14.
Biomed Pharmacother ; 173: 116304, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401519

RESUMO

Glycyrrhetinic acid (GA) shows great efficiency against non-small cell lung cancer (NSCLC), but the detailed mechanism is unclear, which has limited its clinical application. Herein, we investigated the potential targets of GA against NSCLC by activity-based protein profiling (ABPP) technology and the combination of histopathology and proteomics validation. In vitro and in vivo results indicated GA significantly inhibited NSCLC via promotion of peroxiredoxin-6 (Prdx6) and caspase-3 (Casp3)-mediated mitochondrial apoptosis. This original finding will provide theoretical and data support to improve the treatment of NSCLC with the application of GA.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ácido Glicirretínico , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Ácido Glicirretínico/farmacologia , Neoplasias Pulmonares/patologia , Caspase 3 , Peroxirredoxina VI/uso terapêutico , Linhagem Celular Tumoral , Apoptose
15.
J Orthop Surg Res ; 19(1): 152, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395963

RESUMO

BACKGROUND: This study aimed to determine the incidence and influencing factors of venous thromboembolism (VTE) in patients with traumatic rib fractures. METHODS: The retrospective study analyzed medical records of patients with traumatic rib fractures from 33 hospitals. RESULTS: The overall incidence of VTE in hospitalized patients with traumatic rib fractures was 8.1%. Patients with isolated traumatic rib fractures had a significantly lower incidence of VTE (4.4%) compared to patients with rib fractures combined with other injuries (12.0%). Multivariate analysis identified the number of rib fractures as an independent risk factor for thrombosis. Surgical stabilization of isolated rib fractures involving three or more ribs was associated with a lower VTE incidence compared to conservative treatment. CONCLUSIONS: Patients with rib fractures have a higher incidence of VTE, positively correlated with the number of rib fractures. However, the occurrence of thrombosis is relatively low in isolated rib fractures. Targeted thromboprophylaxis strategies should be implemented for these patients, and surgical stabilization of rib fractures may be beneficial in reducing the risk of VTE.


Assuntos
Fraturas das Costelas , Trombose , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Fraturas das Costelas/complicações , Fraturas das Costelas/epidemiologia , Anticoagulantes/uso terapêutico , Incidência , Estudos Retrospectivos , Fatores de Risco , Costelas
16.
Angew Chem Int Ed Engl ; 63(16): e202401394, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38396356

RESUMO

Carbohydrates play pivotal roles in an array of essential biological processes and are consequently involved in many diseases. To meet the needs of glycobiology research, chemical enzymatic and non-enzymatic methods have been developed to generate glycoconjugates with well-defined structures. Herein, harnessing the unique properties of C6-oxidized glycans, we report a straightforward and robust strategy for site- and stereoselective glycomodification of biomolecules with N-terminal tryptophan residues by a carbohydrate-promoted Pictet-Spengler reaction, which is not adapted to typical aldehyde substrates under biocompatible conditions. This method reliably delivers highly homogeneous glycoconjugates with stable linkages and thus has great potential for functional modulation of peptides and proteins in glycobiology research. Moreover, this reaction can be performed at the glycosites of glycopeptides, glycoproteins and living-cell surfaces in a site-specific manner. Control experiments indicated that the protected α-O atom of aldehyde donors and free N-H bond of the tryptamine motif are crucial for this reaction. Mechanistic investigations demonstrated that the reaction exhibited a first-order dependence on both tryptophan and glycan, and deprotonation/rearomatization of the pentahydro-ß-carbolinium ion intermediate might be the rate-determining step.


Assuntos
Carboidratos , Triptofano , Triptofano/química , Proteínas/química , Aldeídos/química , Polissacarídeos , Glicoconjugados
17.
Cell Commun Signal ; 22(1): 139, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378659

RESUMO

BACKGROUND: Malaria remains a global health burden, and the emergence and increasing spread of drug resistance to current antimalarials poses a major challenge to malaria control. There is an urgent need to find new drugs or strategies to alleviate this predicament. Celastrol (Cel) is an extensively studied natural bioactive compound that has shown potentially promising antimalarial activity, but its antimalarial mechanism remains largely elusive. METHODS: We first established the Plasmodium berghei ANKA-infected C57BL/6 mouse model and systematically evaluated the antimalarial effects of Cel in conjunction with in vitro culture of Plasmodium falciparum. The potential antimalarial targets of Cel were then identified using a Cel activity probe based on the activity-based protein profiling (ABPP) technology. Subsequently, the antimalarial mechanism was analyzed by integrating with proteomics and transcriptomics. The binding of Cel to the identified key target proteins was verified by a series of biochemical experiments and functional assays. RESULTS: The results of the pharmacodynamic assay showed that Cel has favorable antimalarial activity both in vivo and in vitro. The ABPP-based target profiling showed that Cel can bind to a number of proteins in the parasite. Among the 31 identified potential target proteins of Cel, PfSpdsyn and PfEGF1-α were verified to be two critical target proteins, suggesting the role of Cel in interfering with the de novo synthesis of spermidine and proteins of the parasite, thus exerting its antimalarial effects. CONCLUSIONS: In conclusion, this study reports for the first time the potential antimalarial targets and mechanism of action of Cel using the ABPP strategy. Our work not only support the expansion of Cel as a potential antimalarial agent or adjuvant, but also establishes the necessary theoretical basis for the development of potential antimalarial drugs with pentacyclic triterpenoid structures, as represented by Cel. Video Abstract.


Assuntos
Antimaláricos , Malária , Animais , Camundongos , Antimaláricos/farmacologia , Antimaláricos/química , Antimaláricos/uso terapêutico , Espermidina/farmacologia , Camundongos Endogâmicos C57BL , Malária/tratamento farmacológico , Malária/parasitologia , Triterpenos Pentacíclicos/uso terapêutico
18.
J Phys Chem B ; 128(6): 1418-1427, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38323538

RESUMO

In cells, wild-type RasGTP complexes exist in two distinct states: active State 2 and inactive State 1. These complexes regulate their functions by transitioning between the two states. However, the mechanisms underlying this state transition have not been clearly elucidated. To address this, we conducted a detailed simulation study to characterize the energetics of the stable states involved in the state transitions of the HRasGTP complex, specifically from State 2 to State 1. This was achieved by employing multiscale quantum mechanics/molecular mechanics and enhanced sampling molecular dynamics methods. Based on the simulation results, we constructed the two-dimensional free energy landscapes that provide crucial information about the conformational changes of the HRasGTP complex from State 2 to State 1. Furthermore, we also explored the conformational changes from the intermediate state to the product state during guanosine triphosphate hydrolysis. This study on the conformational changes involved in the HRas state transitions serves as a valuable reference for understanding the corresponding events of both KRas and NRas as well.


Assuntos
Simulação de Dinâmica Molecular , Proteínas ras , Proteínas ras/metabolismo , Guanosina Trifosfato/metabolismo
19.
Am J Otolaryngol ; 45(3): 104212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38176205

RESUMO

PURPOSE: This study aimed to investigate the vitamin D deficiency of patients with BPPV recurrence and to evaluate the differences of 25-hydroxy vitamin D (25(OH)D) and serum calcium levels among gender and age categories. METHODS: This cross-sectional study enrolled patients with BPPV. The diagnosis of BPPV was based on positional nystagmus and vertigo induced by certain head positions (The Dix-Hallpike maneuver and head roll tests). All patients' age, serum 25(OH)D, calcium measurements and recurrence data were collected and analyzed. RESULTS: The median of 25(OH)D was 15.32 (IQR 10.61, 20.90) ng/ml. The recurrent group showed lower 25(OH)D levels than that of non-recurrent group [13.28 (IQR 9.47, 17.57) ng/ml vs 16.21 (IQR 11.49, 21.13) ng/ml]. There were significant differences of 25(OH)D levels among age categories. The proportion of vitamin D deficiency in patients ≥60 years old was lower than that in the other two groups. CONCLUSION: Our study suggested that BPPV patients had a decreased 25(OH)D level and a high incidence of vitamin D deficiency. The 25(OH)D level of recurrent BPPV patients was lower than that in non-recurrent ones. Among them, the elderly group (≥60 years) took the preponderance, which had the lowest incidence of vitamin D deficiency and the highest incidence of vitamin D sufficiency.


Assuntos
Vertigem Posicional Paroxística Benigna , Cálcio , Recidiva , Deficiência de Vitamina D , Vitamina D , Vitamina D/análogos & derivados , Humanos , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Vitamina D/sangue , Vertigem Posicional Paroxística Benigna/etiologia , Vertigem Posicional Paroxística Benigna/epidemiologia , Vertigem Posicional Paroxística Benigna/sangue , Vertigem Posicional Paroxística Benigna/diagnóstico , Idoso , Adulto , Cálcio/sangue , Fatores Etários , Fatores Sexuais , Incidência
20.
J Med Virol ; 96(2): e29439, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38294104

RESUMO

Hepatitis B virus (HBV) infection is a serious global health problem. After the viruses infect the human body, the host can respond to the virus infection by coordinating various cellular responses, in which mitochondria play an important role. Evidence has shown that mitochondrial proteins are involved in host antiviral responses. In this study, we found that the overexpression of TIM22 and TIM29, the members of the inner membrane translocase TIM22 complex, significantly reduced the level of intracellular HBV DNA and RNA and secreted HBV surface antigens and E antigen. The effects of TIM22 and TIM29 on HBV replication and transcription is attributed to the reduction of core promoter activity mediated by the increased expression of SRSF1 which acts as a suppressor of HBV replication. This study provides new evidence for the critical role of mitochondria in the resistance of HBV infection and new targets for the development of treatment against HBV infection.


Assuntos
Vírus da Hepatite B , Hepatite B , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Fatores de Processamento de Serina-Arginina , Humanos , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Fatores de Processamento de Serina-Arginina/metabolismo , Replicação Viral , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial/metabolismo
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