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2.
Int J Biol Macromol ; : 133791, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992553

RESUMO

Dengue virus (DENV2) is the cause of dengue disease and a worldwide health problem. DENV2 replicates in the host cell using polyproteins such as NS3 protease in conjugation with NS2B cofactor, making NS3 protease a promising antiviral drug-target. This study investigated the efficacy of 'Niloticin' against NS2B/NS3-protease. In silico and in vitro analyses were performed which included interaction of niloticin with NS2B/NS3-protease, protein stability and flexibility, mutation effect, betweenness centrality of residues and analysis of cytotoxicity, protein expression and WNV NS3-protease activity. Similar like acyclovir, niloticin forms strong H-bonds and hydrophobic interactions with residues LEU149, ASN152, LYS74, GLY148 and ALA164. The stability of the niloticin-NS2B/NS3-protease complex was found to be stable compared to the apo NS2B/NS3-protease in structural deviation, PCA, compactness and FEL analysis. The IC50 value of niloticin was 0.14 µM in BHK cells based on in vitro cytotoxicity analysis and showed significant activity at 2.5 µM in a concentration-dependent manner. Western blotting and qRT-PCR analyses showed that niloticin reduced DENV2 protein transcription in a dose-dependent manner. Besides, niloticin confirmed the inhibition of NS3-protease by the SensoLyte 440 WNV protease detection kit. These promising results suggest that niloticin could be an effective antiviral drug against DENV2 and other flaviviruses.

3.
Transl Oncol ; 47: 102040, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954975

RESUMO

BACKGROUND AND PURPOSE: Regorafenib was approved by the US Food and Drug Administration (FDA) for hepatocellular carcinoma (HCC) patients showing progress on sorafenib treatment. However, there is an inevitably high rate of drug resistance associated with regorafenib, which reduces its effectiveness in clinical treatment. Thus, there is an urgent need to find a potential way to solve the problem of regorafenib resistance. The metabolite of disulfiram complexed with copper, the Diethyldithiocarbamate-copper complex (CuET), has been found to be an effective anticancer drug candidate. In the present study, we aimed to evaluate the effect of CuET on regorafenib resistance in HCC and uncover the associated mechanism. EXPERIMENTAL APPROACH: Regorafenib-resistant HCC strains were constructed by applying an increasing concentration gradient. This study employed a comprehensive range of methodologies, including the cell counting kit-8 (CCK-8) assay, colony formation assay, cell cycle analysis, wound healing assay, Transwell assay, tumor xenograft model, and immunohistochemical analysis. These methods were utilized to investigate the antitumor activity of CuET, assess the combined effect of regorafenib and CuET, and elucidate the molecular mechanism underlying CuET-mediated regorafenib resistance. KEY RESULTS: The inhibitory effect of regorafenib on cell survival, proliferation and migration was decreased in regorafenib-resistant MHCC-97H (MHCC-97H/REGO) cells compared with parental cells. CuET demonstrated significant inhibitory effects on cell survival, proliferation, and migration of various HCC cell lines. CuET restored the sensitivity of MHCC-97H/REGO HCC cells to regorafenib in vitro and in vivo. Mechanistically, CuET reverses regorafenib resistance in HCC by suppressing epithelial-mesenchymal transition (EMT) through inhibition of the ERK signaling pathway. CONCLUSION AND IMPLICATIONS: Taken together, the results of this study demonstrated that CuET inhibited the activation of the ERK signaling pathway, leading to the suppression of the epithelial-mesenchymal transition (EMT) and subsequently reversing regorafenib resistance in HCC both in vivo and in vitro. This study provides a new idea and potential strategy to improve the treatment of regorafenib-resistant HCC.

4.
Expert Opin Pharmacother ; 25(10): 1301-1316, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38995220

RESUMO

INTRODUCTION: Since the coronavirus disease 2019-mandated social distancing policy has been lifted worldwide, the circulation of influenza is expected to resume. Currently, oseltamivir is approved as the first-line agent for influenza prevention and treatment. AREAS COVERED: This paper reviews the updated evidence in the pharmacology, resistance mechanisms, clinical pharmacy management, and real-world data on oseltamivir for influenza. EXPERT OPINION: Oseltamivir is an oral prodrug of oseltamivir carboxylate, an influenza A and B neuraminidase inhibitor. Recently, the therapeutic efficacy of oseltamivir has been demonstrated in several trials. Oseltamivir is generally well-tolerated but may lead to neuropsychiatric events and bleeding. Oseltamivir-resistant influenza virus has been associated with the H275Y mutation in the influenza A(H1N1)pdm09 virus, while most strains are still sensitive to oseltamivir. Dose adjustment for oseltamivir should be based on creatinine clearance and body weight in pediatric patients with renal failure. According to real-world data from Nanfang Hospital, the annual number of patients prescribed oseltamivir declined from 35,711 in 2019 to 8,971 in 2020, with marked increases in 2022 (20,213) and 2023 (18,071). Among the 206 inpatients, children aged < 6 years who were treated with oseltamivir had the shortest duration to defervescence.


Assuntos
Antivirais , Farmacorresistência Viral , Influenza Humana , Oseltamivir , Oseltamivir/uso terapêutico , Humanos , Antivirais/uso terapêutico , Influenza Humana/tratamento farmacológico , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética
5.
Acta Pharmacol Sin ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987389

RESUMO

Influenza A virus (IAV) is a widespread pathogen that poses a significant threat to human health, causing pandemics with high mortality and pathogenicity. Given the emergence of increasingly drug-resistant strains of IAV, currently available antiviral drugs have been reported to be inadequate to meet clinical demands. Therefore, continuous exploration of safe, effective and broad-spectrum antiviral medications is urgently required. Here, we found that the small molecule compound J1 exhibited low toxicity both in vitro and in vivo. Moreover, J1 exhibits broad-spectrum antiviral activity against enveloped viruses, including IAV, respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human coronavirus OC43 (HCoV-OC43), herpes simplex virus type 1 (HSV-1) and HSV-2. In this study, we explored the inhibitory effects and mechanism of action of J1 on IAV in vivo and in vitro. The results showed that J1 inhibited infection by IAV strains, including H1N1, H7N9, H5N1 and H3N2, as well as by oseltamivir-resistant strains. Mechanistic studies have shown that J1 blocks IAV infection mainly through specific interactions with the influenza virus hemagglutinin HA2 subunit, thereby blocking membrane fusion. BALB/c mice were used to establish a model of acute lung injury (ALI) induced by IAV. Treatment with J1 increased survival rates and reduced viral titers, lung index and lung inflammatory damage in virus-infected mice. In conclusion, J1 possesses significant anti-IAV effects in vitro and in vivo, providing insights into the development of broad-spectrum antivirals against future pandemics.

6.
Eur J Med Chem ; 275: 116580, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38896994

RESUMO

A new series of racemic fluorescent octahydrophenazines (rac-PZ1-11) have been designed and synthesized via the efficient nucleophilic aromatic substitution (SNAr) of tetrafluorobenzenedinitriles (1a-c) and racemic cyclohexane-1,2-diamines (rac-2a and b). The bioactivities of these racemic rac-PZs (20 µM) against herpes simplex virus type-1 (HSV-1) were evaluated by the relative cell viability of Vero cells infected with HSV-1. It was found that rac-PZ3 shows much higher anti-HSV-1 activity than others, with EC50 = 9.2 ± 1.4 µM. Further investigation into the anti-HSV activities of rac-PZ3 and its enantiomers RR- and SS-PZ3 indicates that rac-PZ3 can also efficiently inhibit HSV-2 and even ACV-resistant HSV-2 (EC50 = 11.0 ± 2.3 and 14.9 ± 2.8 µM, respectively), SS-PZ3 has better activities against HSV-1, HSV-2 and ACV-resistant HSV-2 (EC50 = 4.1 ± 1.1, 5.8 ± 1.0 and 7.9 ± 1.2 µM, respectively), but RR-PZ3 has almost no antiviral activities. The primary mechanism study indicates that rac-PZ3 efficiently reverses the HSV-1/2-induced cytopathic effect and suppresses the expression of viral mRNA and proteins. In addition, rac-, RR- and SS-PZ3 possess excellent fluorescence properties with almost the same emission wavelength and high fluorescence quantum yields (ΦF = 90.3-92.3 % in cyclohexane solutions and 54.4-57.3 % in solids) and can target endoplasmic reticulum and cell membrane. The efficient anti-HSV bioactivities and excellent fluorescence of PZ3 prove its potential applications in antiviral therapy and biological imaging.


Assuntos
Antivirais , Herpesvirus Humano 1 , Herpesvirus Humano 2 , Animais , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/síntese química , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Relação Estrutura-Atividade , Células Vero
7.
Research (Wash D C) ; 7: 0381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840901

RESUMO

Platelet activation contributes to sepsis development, leading to microthrombosis and increased inflammation, which results in disseminated intravascular coagulation and multiple organ dysfunction. Although Cathelicidin can alleviate sepsis, its role in sepsis regulation remains largely unexplored. In this study, we identified Cath-HG, a novel Cathelicidin from Hylarana guentheri skin, and analyzed its structure using nuclear magnetic resonance spectroscopy. The modulatory effect of Cath-HG on the symptoms of mice with sepsis induced by cecal ligation and puncture was evaluated in vivo, and the platelet count, degree of organ damage, and microthrombosis were measured. The antiplatelet aggregation activity of Cath-HG was studied in vitro, and its target was verified. Finally, we further investigated whether Cath-HG could regulate thrombosis in vivo in a FeCl3 injury-induced carotid artery model. The results showed that Cath-HG exhibited an α-helical structure in sodium dodecyl sulfate solution and effectively reduced organ inflammation and damage, improving survival in septic mice. It alleviated sepsis-induced thrombocytopenia and microthrombosis. In vitro, Cath-HG specifically inhibited collagen-induced platelet aggregation and modulated glycoprotein VI (GPVI) signaling pathways. Dot blotting, enzyme-linked immunosorbent assay, and pull-down experiments confirmed GPVI as the target of Cath-HG. Molecular docking and amino acid residue truncations/mutations identified crucial sites of Cath-HG. These findings suggest that GPVI represents a promising therapeutic target for sepsis, and Cath-HG may serve as a potential treatment for sepsis-related thrombocytopenia and thrombotic events. Additionally, identifying Cath-HG as a GPVI inhibitor provides insights for developing novel antithrombotic therapies targeting platelet activation mediated by GPVI.

8.
PLoS One ; 19(6): e0298843, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38917078

RESUMO

Diversity, equity, and inclusion (DEI) mission statements continue to be adopted by academic institutions in general, and by dental schools around the globe in particular. But DEI content seems to be under-developed in dental education. The objectives of this study were two-fold: to extract information from all the PBL cases at University of British Columbia's Faculty of Dentistry curriculum in terms of the diversity, equitable representation, and inclusion of patient and provider characteristics, context, and treatment outcomes; and; to compare these findings with the composition of the British Columbia census population, dental practice contextual factors, and the evidence on treatment outcomes within patient care. Information from all the 58 PBL cases was extracted between January and March 2023, focusing on patient and provider characteristics (e.g., age, gender, ethnicity), context (e.g., type of insurance), and treatment outcomes (e.g., successful/unsuccessful). This information was compared with the available literature. From all the 58 PBL cases, 0.4% included non-straight patients, while at least 4% of BC residents self-identify as non-straight; there were no cases involving First Nations patients although they make up 6% of the British Columbia population. Less than 10% of the cases involved older adults who make up almost 20% of the population. Only Treatments involving patients without a disability were 5.74 times more likely to be successful compared to those involving patients with a disability (p<0.05). The characteristics of the patients, practice context, and treatment outcomes portrayed in the existing PBL cases seem to differ from what is known about the composition of the British Columbia population, treatment outcome success, and practice context; a curriculum disconnect seems to exist. The PBL cases should be revised to better represent the population within which most students will practice.


Assuntos
Currículo , Aprendizagem Baseada em Problemas , Humanos , Colúmbia Britânica , Masculino , Feminino , Diversidade Cultural , Educação em Odontologia , Adulto
9.
Cell Rep ; 43(5): 114142, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38691458

RESUMO

Despite medical advances, there remains an unmet need for better treatment of obesity. Itaconate, a product of the decarboxylation of the tricarboxylic acid cycle intermediate cis-aconitate, plays a regulatory role in both metabolism and immunity. Here, we show that itaconate, as an endogenous compound, counteracts high-fat-diet (HFD)-induced obesity through leptin-independent mechanisms in three mouse models. Specifically, itaconate reduces weight gain, reverses hyperlipidemia, and improves glucose tolerance in HFD-fed mice. Additionally, itaconate enhances energy expenditure and the thermogenic capacity of brown adipose tissue (BAT). Unbiased proteomic analysis reveals that itaconate upregulates key proteins involved in fatty acid oxidation and represses the expression of lipogenic genes. Itaconate may provoke a major metabolic reprogramming by inducing fatty acid oxidation and suppression of fatty acid synthesis in BAT. These findings highlight itaconate as a potential activator of BAT-mediated thermogenesis and a promising candidate for anti-obesity therapy.


Assuntos
Adipócitos Marrons , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Obesidade , Succinatos , Termogênese , Animais , Termogênese/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Succinatos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Camundongos , Masculino , Adipócitos Marrons/metabolismo , Adipócitos Marrons/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos
10.
Food Chem X ; 22: 101369, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38633743

RESUMO

Malolactic fermentation (MLF) is a crucial process to enhance wine quality, and the utilization of indigenous microorganisms has the potential to enhance wine characteristics distinct to a region. Here, the MLF performance of five indigenous Oenococcus oeni strains and six synthetic microbial communities (SynComs), were comparatively evaluated in Cabernet Sauvignon wine. In terms of malate metabolism rate and wine aroma diversity, the strain of O. oeni Oe114-46 demonstrated comparable MLF performance to the commercial strain of O. oeni Oe450 PreAc. Furthermore, the corresponding SynComs (Oe144-46/LpXJ25) exhibited improved fermentation properties, leading to increased viable cell counts of both species, more rapid and thorough MLF, and increased concentrations of important aroma compounds, such as linalool, 4-terpinenol, α-terpineol, diethyl succinate, and ethyl lactate. These findings highlight the remarkable MLF performance of indigenous O. oeni and O. oeni-L. plantarum microbial communities, emphasizing their immense potential in improving MLF efficiency and wine quality.

11.
Sci Signal ; 17(831): eadg7867, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593156

RESUMO

Type I interferons (IFNs) are critical for the antiviral immune response, and fine-tuning type I IFN production is critical to effectively clearing viruses without causing harmful immunopathology. We showed that the transcription factor Miz1 epigenetically repressed the expression of genes encoding type I IFNs in mouse lung epithelial cells by recruiting histone deacetylase 1 (HDAC1) to the promoters of Ifna and Ifnb. Loss of function of Miz1 resulted in augmented production of these type I IFNs during influenza A virus (IAV) infection, leading to improved viral clearance in vitro and in vivo. IAV infection induced Miz1 accumulation by promoting the cullin-4B (CUL4B)-mediated ubiquitylation and degradation of the E3 ubiquitin ligase Mule (Mcl-1 ubiquitin ligase E3; also known as Huwe1 or Arf-BP1), which targets Miz1 for degradation. As a result, Miz1 accumulation limited type I IFN production and favored viral replication. This study reveals a previously unrecognized function of Miz1 in regulating antiviral defense and a potential mechanism for influenza viruses to evade host immune defense.


Assuntos
Vírus da Influenza A , Influenza Humana , Interferon Tipo I , Camundongos , Animais , Humanos , Vírus da Influenza A/fisiologia , Ubiquitinação , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Replicação Viral , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Influenza Humana/genética , Interferons/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Inibidoras de STAT Ativados/genética , Proteínas Inibidoras de STAT Ativados/metabolismo
12.
Food Chem ; 450: 139379, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38653050

RESUMO

Raspberries are known to contain valuable metabolites and possess a robust antioxidant capacity. However, the impact of different tablet processing stages on the nutritional content and flavor profile of raspberries remains unclear. The dynamic profile of functional and volatile metabolites was investigated through foodomics combined with UPLC-MS/MS-based widely targeted metabolomics and HS-SPME-GC-MS, and antioxidant capacities were assessed during tablet processing. 1336 functional metabolites and 645 volatile metabolites were identified. Results indicated tablets retained 34% âˆ¼ 61% of the total volatile contents. In addition, the conversion intensity of functional metabolites was consistent with the order of "Tableting > Freeze-drying > Crushing". Compared to raspberry, tablets showed higher antioxidant activity, which was positively correlated with vitamin contents. This study elucidated that tablet formation demonstrated advantages in antioxidation and aroma retention, which may provide insights for enhancing quality during the tableting process.


Assuntos
Antioxidantes , Rubus , Comprimidos , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Antioxidantes/metabolismo , Antioxidantes/química , Antioxidantes/análise , Rubus/química , Rubus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Metabolômica , Frutas/química , Frutas/metabolismo , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos , Odorantes/análise , Extratos Vegetais/química , Extratos Vegetais/metabolismo
13.
Foods ; 13(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38672831

RESUMO

Grape pomace seeds contain abundant phenolic compounds, which are also present in both soluble and insoluble forms, similar to many other plant matrices. To further increase the extractable soluble phenolics and their antioxidant activities, grape pomace seeds were fermented with different fungi. Results showed that solid-state fermentation (SSF) with Aspergillus niger, Monascus anka, and Eurotium cristatum at 28 °C and 65% humidity had a significantly positive impact on the release of soluble phenolics in grape pomace seeds. Specifically, SSF with M. anka increased the soluble phenolic contents by 6.42 times (calculated as total phenolic content) and 6.68 times (calculated as total flavonoid content), leading to an overall improvement of antioxidant activities, including DPPH (increased by 2.14 times) and ABTS (increased by 3.64 times) radical scavenging activity. Furthermore, substantial changes were observed in the composition and content of individual phenolic compounds in the soluble fraction, with significantly heightened levels of specific phenolics such as chlorogenic acid, syringic acid, ferulic acid, epicatechin gallate, and resveratrol. Notably, during M. anka SSF, positive correlations were identified between the soluble phenolic content and hydrolase activities. In particular, there is a strong positive correlation between glycosidase and soluble phenols (r = 0.900). The findings present an effective strategy for improving the soluble phenolic profiles and bioactivities of grape pomace seeds through fungal SSF, thereby facilitating the valorization of winemaking by-products.

14.
Arthritis Res Ther ; 26(1): 64, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459604

RESUMO

BACKGROUND: Lupus nephritis (LN) is the most common complication of systemic lupus erythematosus (SLE). The limited treatment options for LN increase the economic burdens on patients. Because fibrotic progression leads to irreversible renal damage in LN patients and further progresses to chronic kidney disease (CKD) and the end stage of renal disease (ESRD), developing new targets to prevent LN fibrotic progression could lead to a feasible treatment strategy for LN patients. METHODS: In this study, we examined YAP activation and LATS2 downregulation in LN kidney biopsy samples (LN: n = 8, normal: n = 2) and lupus-prone MRL/lpr mice (n = 8 for each disease stage). The function of LATS2 was further investigated by in situ injection of Ad-LATS2 into mice with LN (n = 6 mice per group). We examined the role of SIAH2-LATS2 regulation by IP-MS and co-IP, and the protective effect of the SIAH2 inhibitor was investigated in mice with LN. RESULTS: Restoring LATS2 by an adenovirus in vivo alleviated renal fibrotic damage in mice with LN. Moreover, we found that LATS2 was degraded by a K48 ubiquitination-proteasome pathway mediated by SIAH2 and promoted YAP activation to worsen fibrosis progression in LN. The H150 region of the substrate binding domain (SBD) is an important site for SIAH2-LATS2 binding. The SIAH2-specific inhibitor vitamin K3 protected against LN-associated fibrotic damage in vivo. CONCLUSION: In summary, we identified the SIAH2-LATS2 axis as an attractive intervention target in LN to alter the resistance to fibrosis.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Camundongos , Animais , Nefrite Lúpica/metabolismo , Vitamina K 3 , Camundongos Endogâmicos MRL lpr , Rim/patologia , Lúpus Eritematoso Sistêmico/patologia , Fibrose , Proteínas Serina-Treonina Quinases , Proteínas Supressoras de Tumor
15.
Acta Pharm Sin B ; 14(3): 1362-1379, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38486996

RESUMO

Extracellular vesicles (EVs) have recently emerged as a promising delivery platform for CRISPR/Cas9 ribonucleoproteins (RNPs), owing to their ability to minimize off-target effects and immune responses. However, enhancements are required to boost the efficiency and safety of Cas9 RNP enrichment within EVs. In response, we employed the Fc/Spa interaction system, in which the human Fc domain was fused to the intracellular domain of PTGFRN-Δ687 and anchored to the EV membrane. Simultaneously, the B domain of the Spa protein was fused to the C domain of cargos such as Cre or spCas9. Due to the robust interaction between Fc and Spa, this method enriched nearly twice the amount of cargo within the EVs. EVs loaded with spCas9 RNP targeting the HSV1 genome exhibited significant inhibition of viral replication in vitro and in vivo. Moreover, following neuron-targeting peptide RVG modification, the in vivo dosage in neural tissues substantially increased, contributing to the clearance of the HSV1 virus in neural tissues and exhibiting a lower off-target efficiency. These findings establish a robust platform for efficient EV-based SpCas9 delivery, offering potential therapeutic advantages for HSV1 infections and other neurological disorders.

16.
J Med Virol ; 96(3): e29528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38501378

RESUMO

The emerging Omicron subvariants have a remarkable ability to spread and escape nearly all current monoclonal antibody (mAb) treatments. Although the virulence of SARS-CoV-2 has now diminished, it remains a significant threat to public health due to its high transmissibility and susceptibility to mutation. Therefore, it is urgent to develop broad-acting and potent therapeutics targeting current and emerging Omicron variants. Here, we identified a panel of Omicron BA.1 spike receptor-binding domain (RBD)-targeted nanobodies (Nbs) from a naive alpaca VHH library. This panel of Nbs exhibited high binding affinity to the spike RBD of wild-type, Alpha B.1.1.7, Beta B.1.351, Delta plus, Omicron BA.1, and BA.2. Through multivalent Nb construction, we obtained a subpanel of ultrapotent neutralizing Nbs against Omicron BA.1, BA.2, BF.7 and even emerging XBB.1.5, and XBB.1.16 pseudoviruses. Protein structure prediction and docking analysis showed that Nb trimer 2F2E5 targets two independent RBD epitopes, thus minimizing viral escape. Taken together, we obtained a panel of broad and ultrapotent neutralizing Nbs against Omicron BA.1, Omicron BA.2, BF.7, XBB.1.5, and XBB.1.16. These multivalent Nbs hold great promise for the treatment against SARS-CoV-2 infection and could possess a superwide neutralizing breadth against novel omicron mutants or recombinants.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos de Domínio Único , Humanos , Anticorpos de Domínio Único/genética , Anticorpos Monoclonais , Epitopos , Anticorpos Neutralizantes , Anticorpos Antivirais
17.
BMC Genomics ; 25(1): 260, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38454328

RESUMO

In this study, we conducted an assembly and analysis of the organelle genomes of Aconitum carmichaelii. Our investigation encompassed the examination of organelle genome structures, gene transfer events, and the environmental selection pressures affecting A. carmichaelii. The results revealed distinct evolutionary patterns in the organelle genomes of A. carmichaelii. Especially, the plastome exhibited a more conserved structure but a higher nucleotide substitution rate (NSR), while the mitogenome displayed a more complex structure with a slower NSR. Through homology analysis, we identified several instances of unidirectional protein-coding genes (PCGs) transferring from the plastome to the mitogenome. However, we did not observe any events which genes moved from the mitogenome to the plastome. Additionally, we observed multiple transposable element (TE) fragments in the organelle genomes, with both organelles showing different preferences for the type of nuclear TE insertion. Divergence time estimation suggested that rapid differentiation occurred in Aconitum species approximately 7.96 million years ago (Mya). This divergence might be associated with the reduction in CO2 levels and the significant uplift of the Qinghai-Tibet Plateau (QTP) during the late Miocene. Selection pressure analysis indicated that the dN/dS values of both organelles were less than 1, suggested that organelle PCGs were subject to purification selection. However, we did not detect any positively selected genes (PSGs) in Subg. Aconitum and Subg. Lycoctonum. This observation further supports the idea that stronger negative selection pressure on organelle genes in Aconitum results in a more conserved amino acid sequence. In conclusion, this study contributes to a deeper understanding of organelle evolution in Aconitum species and provides a foundation for future research on the genetic mechanisms underlying the structure and function of the Aconitum plastome and mitogenome.


Assuntos
Aconitum , Filogenia , Aconitum/genética , Aconitum/química , Aconitum/metabolismo , Organelas/genética , Tibet
18.
Cell Mol Immunol ; 21(5): 479-494, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38443447

RESUMO

Apart from mediating viral entry, the function of the free HIV-1 envelope protein (gp120) has yet to be elucidated. Our group previously showed that EP2 derived from one ß-strand in gp120 can form amyloid fibrils that increase HIV-1 infectivity. Importantly, gp120 contains ~30 ß-strands. We examined whether gp120 might serve as a precursor protein for the proteolytic release of amyloidogenic fragments that form amyloid fibrils, thereby promoting viral infection. Peptide array scanning, enzyme degradation assays, and viral infection experiments in vitro confirmed that many ß-stranded peptides derived from gp120 can indeed form amyloid fibrils that increase HIV-1 infectivity. These gp120-derived amyloidogenic peptides, or GAPs, which were confirmed to form amyloid fibrils, were termed gp120-derived enhancers of viral infection (GEVIs). GEVIs specifically capture HIV-1 virions and promote their attachment to target cells, thereby increasing HIV-1 infectivity. Different GAPs can cross-interact to form heterogeneous fibrils that retain the ability to increase HIV-1 infectivity. GEVIs even suppressed the antiviral activity of a panel of antiretroviral agents. Notably, endogenous GAPs and GEVIs were found in the lymphatic fluid, lymph nodes, and cerebrospinal fluid (CSF) of AIDS patients in vivo. Overall, gp120-derived amyloid fibrils might play a crucial role in the process of HIV-1 infectivity and thus represent novel targets for anti-HIV therapeutics.


Assuntos
Amiloide , Proteína gp120 do Envelope de HIV , Infecções por HIV , HIV-1 , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/fisiologia , Humanos , Amiloide/metabolismo , Infecções por HIV/virologia , Infecções por HIV/metabolismo , Proteínas Amiloidogênicas/metabolismo , Vírion/metabolismo , Peptídeos/metabolismo , Peptídeos/química , Peptídeos/farmacologia
19.
Curr Biol ; 34(5): R191-R192, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38471444

RESUMO

Blinking is a behavior unique to animal taxa with motile eyelids, such as most amphibians and reptiles as well as all birds and mammals1. Eyelid movement has physiological functions, such as lubricating the cornea and washing away dust, but its potential signaling functions are not well understood1,2. The use of eyeblinks as a social signal is currently thought to be restricted to some primates, especially humans and their companion animals, but has not been verified in other taxa1,3,4. Here, through field observation and experiments, we demonstrate that female concave-eared torrent frogs (Odorrana tormota), which inhabit noisy streams, use eyeblinks to communicate with males to urge them to initiate amplexus for mating. Our findings reveal that eyeblinks may serve as a social signal in non-primate species.


Assuntos
Anuros , Piscadela , Animais , Masculino , Feminino , Humanos , Anuros/fisiologia , Ranidae/fisiologia , Ruído , Mamíferos
20.
Mol Cell Proteomics ; 23(5): 100756, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554776

RESUMO

In orthotopic mouse tumor models, tumor progression is a complex process, involving interactions among tumor cells, host cell-derived stromal cells, and immune cells. Much attention has been focused on the tumor and its tumor microenvironment, while the host's macroenvironment including immune organs in response to tumorigenesis is poorly understood. Here, we report a temporal proteomic analysis on a subcutaneous tumor and three immune organs (LN, MLN, and spleen) collected on Days 0, 3, 7, 10, 14, and 21 after inoculation of mouse forestomach cancer cells in a syngeneic mouse model. Bioinformatics analysis identified key biological processes during distinct tumor development phases, including an initial acute immune response, the attack by the host immune system, followed by the adaptive immune activation, and the build-up of extracellular matrix. Proteomic changes in LN and spleen largely recapitulated the dynamics of the immune response in the tumor, consistent with an acute defense response on D3, adaptive immune response on D10, and immune evasion by D21. In contrast, the immune response in MLN showed a gradual and sustained activation, suggesting a delayed response from a distal immune organ. Combined analyses of tumors and host immune organs allowed the identification of potential therapeutic targets. A proof-of-concept experiment demonstrated that significant growth reduction can be achieved by dual inhibition of MEK and DDR2. Together, our temporal proteomic dataset of tumors and immune organs provides a useful resource for understanding the interaction between tumors and the immune system and has the potential for identifying new therapeutic targets for cancer treatment.


Assuntos
Proteômica , Baço , Animais , Proteômica/métodos , Camundongos , Baço/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Linfonodos/metabolismo , Proteoma/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia , Feminino
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