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1.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
2.
Immunity ; 46(3): 446-456, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28314593

RESUMO

Zika virus (ZIKV) has become a public health threat due to its global transmission and link to severe congenital disorders. The host immune responses to ZIKV infection have not been fully elucidated, and effective therapeutics are not currently available. Herein, we demonstrated that cholesterol-25-hydroxylase (CH25H) was induced in response to ZIKV infection and that its enzymatic product, 25-hydroxycholesterol (25HC), was a critical mediator of host protection against ZIKV. Synthetic 25HC addition inhibited ZIKV infection in vitro by blocking viral entry, and treatment with 25HC reduced viremia and conferred protection against ZIKV in mice and rhesus macaques. 25HC suppressed ZIKV infection and reduced tissue damage in human cortical organoids and the embryonic brain of the ZIKV-induced mouse microcephaly model. Our findings highlight the protective role of CH25H during ZIKV infection and the potential use of 25HC as a natural antiviral agent to combat ZIKV infection and prevent ZIKV-associated outcomes, such as microcephaly.


Assuntos
Antivirais/farmacologia , Hidroxicolesteróis/farmacologia , Microcefalia/virologia , Infecção por Zika virus/complicações , Animais , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Imunofluorescência , Humanos , Macaca mulatta , Camundongos , Microscopia Confocal , Internalização do Vírus/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Zika virus/fisiologia
3.
EMBO Rep ; 24(7): e56458, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37249035

RESUMO

DNA topoisomerase IIα (TOP2A) plays a vital role in replication and cell division by catalytically altering DNA topology. It is a prominent target for anticancer drugs, but clinical efficacy is often compromised due to chemoresistance. In this study, we investigate the role of TOP2A O-GlcNAcylation in breast cancer cells and patient tumor tissues. Our results demonstrate that elevated TOP2A, especially its O-GlcNAcylation, promotes breast cancer malignant progression and resistance to adriamycin (Adm). O-GlcNAcylation at Ser1469 enhances TOP2A chromatin DNA binding and catalytic activity, leading to resistance to Adm in breast cancer cells and xenograft models. Mechanistically, O-GlcNAcylation-modulated interactions between TOP2A and cell cycle regulators influence downstream gene expression and contribute to breast cancer drug resistance. These results reveal a previously unrecognized mechanistic role for TOP2A O-GlcNAcylation in breast cancer chemotherapy resistance and provide support for targeting TOP2A O-GlcNAcylation in cancer therapy.


Assuntos
Antineoplásicos , Neoplasias da Mama , Feminino , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos
4.
Small ; : e2402164, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881322

RESUMO

Thin and flexible solid-state electrolyte (SSE) films with high ionic conductivity and low interfacial resistance are urgently required for lithium metal batteries (LMBs). However, it's still challenging to reduce the film thickness to <20 µm, especially for those with high ceramic contents. Herein, a facile slurry casting method is developed to prepare the ultra-thin (14 µm) Li3Zr2Si2PO12 (LZSP) films with ceramic content up to 91% using a composite polymer binder, polyvinylidene fluoride (PVDF), and polyethylene oxide (PEO). It shows that PEO not only enhanced the film flexibility but also makes it be easily peeled off to form a freestanding membrane, PLN. To promote the interfacial ion transport, PEO/lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) is introduced to the film surface, and the resultant tri-layer film, PPLN, shows a satisfying room temperature ionic conductivity of 0.116 mS cm-1, high Li+ transference number of 0.79, and good compatibility with metal lithium. As a result, LMBs using LiFePO4 cathode and PPLN electrolyte exhibit excellent safety as well as electrochemical performances in the wide temperature range between room temperature (RT) and 100 °C.

5.
J Transl Med ; 22(1): 589, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38915068

RESUMO

BACKGROUND: Predictive markers for fecal microbiota transplantation (FMT) outcomes in patients with active ulcerative colitis (UC) are poorly defined. We aimed to investigate changes in gut microbiota pre- and post-FMT and to assess the potential value in determining the total copy number of fecal bacterial siderophore genes in predicting FMT responsiveness. METHODS: Patients with active UC (Mayo score ≥ 3) who had undergone two FMT procedures were enrolled. Fecal samples were collected before and 8 weeks after each FMT session. Patients were classified into clinical response and non-response groups, based on their Mayo scores. The fecal microbiota profile was accessed using metagenomic sequencing, and the total siderophore genes copy number via quantitative real-time polymerase chain reaction. Additionally, we examined the association between the total siderophore genes copy number and FMT efficacy. RESULTS: Seventy patients with UC had undergone FMT. The clinical response and remission rates were 50% and 10% after the first FMT procedure, increasing to 72.41% and 27.59% after the second FMT. The cumulative clinical response and clinical remission rates were 72.86% and 25.71%. Compared with baseline, the response group showed a significant increase in Faecalibacterium, and decrease in Enterobacteriaceae, consisted with the changes of the total bacterial siderophore genes copy number after the second FMT (1889.14 vs. 98.73 copies/ng, P < 0.01). Virulence factor analysis showed an enriched iron uptake system, especially bacterial siderophores, in the pre-FMT response group, with a greater contribution from Escherichia coli. The total baseline copy number was significantly higher in the response group than non-response group (1889.14 vs. 94.86 copies/ng, P < 0.01). A total baseline copy number cutoff value of 755.88 copies/ng showed 94.7% specificity and 72.5% sensitivity in predicting FMT responsiveness. CONCLUSIONS: A significant increase in Faecalibacterium, and decrease in Enterobacteriaceae and the total fecal siderophore genes copy number were observed in responders after FMT. The siderophore genes and its encoding bacteria may be of predictive value for the clinical responsiveness of FMT to active ulcerative colitis.


Assuntos
Colite Ulcerativa , Transplante de Microbiota Fecal , Fezes , Microbioma Gastrointestinal , Sideróforos , Humanos , Colite Ulcerativa/terapia , Colite Ulcerativa/microbiologia , Colite Ulcerativa/genética , Masculino , Feminino , Fezes/microbiologia , Adulto , Pessoa de Meia-Idade , Microbioma Gastrointestinal/genética , Sideróforos/metabolismo , Resultado do Tratamento , Bactérias/genética , Genes Bacterianos , Dosagem de Genes , Curva ROC
6.
Neuroendocrinology ; 114(7): 605-622, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547853

RESUMO

INTRODUCTION: Irritable bowel syndrome with diarrhea (IBS-D) is frequently accompanied by depression and anxiety, resulting in a reduced quality of life and increased medical expenditures. Although psychological factors are known to play an important role in the genesis and development of IBS-D, an understanding of the central neural control of intestinal dysfunction remains elusive. Melanin-concentrating hormone (MCH) is a gut-brain peptide involved in regulating feeding, sleep-wake rhythms, and emotional states. METHODS: This study investigated the regulation of the MCHergic neural circuit from the lateral hypothalamic area (LHA) to the dorsal raphe nucleus (DRN) on anxiety- and depression-like behaviors, intestinal motility, and visceral hypersensitivity in a mice model of IBS-D. The models of IBS-D were prepared by inducing chronic unpredictable mild stress. RESULTS: Chemogenetic activation of the MCH neurons in the LHA could excite serotonin (5-HT) neurons in the DRN and induce anxiety- and depression-like behaviors and IBS-D-like symptoms, which could be recovered by microinjection of the MCH receptor antagonist SNAP94847 into the DRN. The mice model of IBS-D showed a reduction of 5-HT and brain-derived neurotrophic factor (BDNF) expression in the DRN, while an elevation of 5-HT and BDNF was observed in the colon through immunofluorescent staining, ELISA, and Western blot analysis. SNAP94847 treatment in the DRN alleviated anxiety- and depression-like behaviors, improved intestinal motility, and alleviated visceral hypersensitivity responses by normalizing the 5-HT and BDNF expression in the DRN and colon. CONCLUSION: This study suggests that the activation of MCH neurons in the LHA may induce IBS-D symptoms via the DRN and that the MCH receptor antagonist could potentially have therapeutic effects.


Assuntos
Diarreia , Modelos Animais de Doenças , Núcleo Dorsal da Rafe , Hormônios Hipotalâmicos , Síndrome do Intestino Irritável , Melaninas , Hormônios Hipofisários , Animais , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/fisiopatologia , Núcleo Dorsal da Rafe/metabolismo , Hormônios Hipofisários/metabolismo , Hormônios Hipotalâmicos/metabolismo , Camundongos , Diarreia/metabolismo , Diarreia/etiologia , Masculino , Melaninas/metabolismo , Camundongos Endogâmicos C57BL , Motilidade Gastrointestinal/fisiologia , Motilidade Gastrointestinal/efeitos dos fármacos , Serotonina/metabolismo , Emoções/fisiologia , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Ansiedade/etiologia , Ansiedade/fisiopatologia , Ansiedade/metabolismo , Depressão/etiologia , Depressão/metabolismo , Depressão/fisiopatologia , Comportamento Animal/fisiologia
7.
Biol Pharm Bull ; 47(6): 1179-1188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38880626

RESUMO

Secondary lymphedema occurs after cancer surgery involving lymph node dissection owing to the lymphatic system dysfunction. However, the pathophysiology of lymphedema and the molecular pathways involved remain unknown. This study aimed to develop a rat hindlimb lymphedema model and investigate the mechanisms that drive pathophysiology and the effects of the traditional Japanese medicine goreisan on lymphedema. The rat lymphedema model was induced by combination surgeries of popliteal lymph node dissection, skin cautery incision, and fascial ablation coagulation in the right hindlimb using male Wistar rats. The foot volume was significantly increased, and recovery was delayed by combination surgeries. Dermal thickness and dilated lymphatic vessels of the hindlimb were observed on postoperative day 2. The number of infiltrating leukocytes (CD45+ cells), including CD4+ T-cells, increased in the lymphedema group compared with that in the sham group. The relative mRNA expression and protein levels of interleukin-6 (IL-6), CC chemokine ligand 2 (CCL2), transforming growth factor ß1 (TGF-ß1), and Fms-related receptor tyrosine kinase 4 (FLT4) were significantly higher in the lymphedema group than in the sham group. Foot volume was decreased by goreisan, furosemide, and prednisolone treatments. Goreisan diminished the increase in CD4+ T-cells, and the same trend was observed for CCL2 and FLT4 expression. In conclusion, the rat hindlimb lymphedema model in this study exhibited increased foot volume, skin-infiltrating cells, and pathological changes accompanied by inflammatory and fibrotic responses, suggesting that the model presented significant clinical features of lymphedema. Goreisan may exert a therapeutic effect on lymphedema by inhibiting CD4+ T-cell infiltration.


Assuntos
Membro Posterior , Linfedema , Animais , Masculino , Ratos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Modelos Animais de Doenças , Linfedema/tratamento farmacológico , Medicina Tradicional do Leste Asiático , Ratos Wistar
8.
Molecules ; 29(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38257283

RESUMO

Obesity has become a major disease that endangers human health. Studies have shown that dietary interventions can reduce the prevalence of obesity and diabetes. Resistant starch (RS) exerts anti-obesity effects, alleviates metabolic syndrome, and maintains intestinal health. However, different RS types have different physical and chemical properties. Current research on RS has focused mainly on RS types 2, 3, and 4, with few studies on RS1. Therefore, this study aimed to investigate the effect of RS1 on obesity and gut microbiota structure in mice. In this study, we investigated the effect of potato RS type 1 (PRS1) on obesity and inflammation. Mouse weights, as well as their food intake, blood glucose, and lipid indexes, were assessed, and inflammatory factors were measured in the blood and tissues of the mice. We also analyzed the expression levels of related genes using PCR, with 16S rRNA sequencing used to study intestinal microbiota changes in the mice. Finally, the level of short-chain fatty acids was determined. The results indicated that PRS1 promoted host obesity and weight gain and increased blood glucose and inflammatory cytokine levels by altering the gut microbiota structure.


Assuntos
Microbioma Gastrointestinal , Solanum tuberosum , Humanos , Animais , Camundongos , Amido Resistente , Dieta Hiperlipídica/efeitos adversos , Glicemia , RNA Ribossômico 16S , Amido/farmacologia , Obesidade/etiologia
9.
J Sci Food Agric ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829244

RESUMO

BACKGROUND: Bacterial fruit blotch (BFB), known as the 'cancer' of cucurbits, is a seed-borne disease of melons caused by Acidovorax citrulli. Traditional chemical treatments for BFB are ineffective and adversely affect the environment. Using dielectric barrier discharge (DBD) nanosecond-pulsed plasma technology, melon seeds were treated to promote germination and growth and to control BFB. RESULTS: Based on the evaluation parameters of seed germination, seedling growth, leaf yellowing and bacterial infection after seed plasma treatments, 9 min at 20 kV was selected as the optimal plasma discharge parameter. In this study, seedling growth was significantly improved after treating melon seeds carrying A. citrulli using this discharge parameter. The number of first true leaves measured on the eighth day was 2.3 times higher and the disease index was reduced by 60.5% compared to the control group. Attenuated total reflectance-Fourier transform infrared measurements show that plasma treatments penetrate the seed coat and denature polysaccharides and proteins in the seed kernel, affecting their growth and sterilization properties. CONCLUSION: Pre-sowing treatment of melon seeds carrying A. citrulli using nanosecond-pulsed plasma technology can effectively control seedling BFB disease and promote melon seedling growth by optimizing DBD parameters. © 2024 Society of Chemical Industry.

10.
BMC Plant Biol ; 23(1): 274, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37221486

RESUMO

BACKGROUND: Previous studies of the relationships between traits have focused on the natural growth conditions of wild plants. Urban garden plants exhibit some differences in plant traits due to environmental interference. It is unknown whether the relationships between the leaf traits of urban garden plants differ under distinct climates. In this study, we revealed the variation characteristics of the leaf functional traits of trees, shrubs, and vines in two urban locations. Two-way ANOVA was used to reveal the response of plant leaf traits to climate and life forms. Pearson correlation analysis and principal component analysis were used to calculate the correlation coefficient between the leaf functional traits of plants at the two locations. RESULTS: Leaf dry matter content (LDMC) and vein density (VD) of different life forms in Mudanjiang were higher than those in Bozhou (P < 0.05), and the relative water content (RWC) in Bozhou was higher, whereas vein density (VD) of trees and shrubs in the two urban locations was significant (P < 0.05), but the vines were not significant. The photosynthetic pigments of tree and shrub species were larger in Mudanjiang, but the opposite was true for the vines. Both leaf vein density (VD) and stomatal density (SD) showed a very significant positive correlation in the two urban locations (P < 0.01), and both were significantly positively correlated with specific leaf area (SLA) (P < 0.05); and negatively correlated with leaf thickness (LT), and the relationship between pigment content were closer. CONCLUSION: The response to climate showed obvious differences in leaf traits of different life forms species in urban area, but the correlations between the traits showed convergence, which reflects that the adaptation strategies of garden plant leaves to different habitats are both coordinated and relatively independent.


Assuntos
Aclimatação , Jardins , Árvores , China , Folhas de Planta
11.
J Transl Med ; 21(1): 680, 2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37777783

RESUMO

BACKGROUND: Metagenomic next-generation sequencing (mNGS) has become a powerful tool for pathogen detection, but the value of human sequencing reads generated from it is underestimated. METHODS: A total of 138 patients with pleural effusion (PE) were diagnosed with tuberculous pleurisy (TBP, N = 82), malignant pleural effusion (MPE, N = 35), or non-TB infection (N = 21), whose PE samples all underwent mNGS analysis. Clinical TB tests including culture, Acid-Fast Bacillus (AFB) test, Xpert, and T-SPOT, were performed. To utilize mNGS for MPE identification, 25 non-MPE samples (20 TBP and 5 non-TB infection) were randomly selected to set human chromosome copy number baseline and generalized linear modeling was performed using copy number variant (CNV) features of the rest 113 samples (35 MPE and 78 non-MPE). RESULTS: The performance of TB detection was compared among five methods. T-SPOT demonstrated the highest sensitivity (61% vs. culture 32%, AFB 12%, Xpert 35%, and mNGS 49%) but with the highest false-positive rate (10%) as well. In contrast, mNGS was able to detect TB-genome in nearly half (40/82) of the PE samples from TBP subgroup, with 100% specificity. To evaluate the performance of using CNV features of the human genome for MPE prediction, we performed the leave-one-out cross-validation (LOOCV) in the subcohort excluding the 25 non-MPE samples for setting copy number standards, which demonstrated 54.1% sensitivity, 80.8% specificity, 71.7% accuracy, and an AUC of 0.851. CONCLUSION: In summary, we exploited the value of human and non-human sequencing reads generated from mNGS, which showed promising ability in simultaneously detecting TBP and MPE.


Assuntos
Derrame Pleural Maligno , Derrame Pleural , Tuberculose Pleural , Humanos , Tuberculose Pleural/diagnóstico , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/genética , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Sensibilidade e Especificidade
12.
J Med Virol ; 95(1): e28290, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367083

RESUMO

The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015-2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1-/- ) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50 ). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.


Assuntos
Infecção por Zika virus , Zika virus , Animais , Camundongos , Filogenia , Infecção por Zika virus/epidemiologia , Camboja/epidemiologia , Ásia/epidemiologia
13.
Clin Genet ; 103(3): 352-357, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36373164

RESUMO

Ovarian dysfunction, including premature ovarian insufficiency and decreased ovarian reserve, affects the ovarian reserve and is one of the leading causes of female infertility. More and more cases of ovarian dysfunction are associated with genetic factors. Here, we identified eight potential variants in five genes (MSH4, HFM1, SYCE1, FSHR, and C14orf39) from six independent families by exome sequencing. The splice-site variants in SYCE1 and MSH4 affected canonical splicing isoforms, leading to missing protein domains or premature termination. Our findings expand the mutational spectrum of ovarian dysfunction and provide potential biomarkers for future genetic counseling and for more personalized treatments. Exome sequencing was shown to be a useful tool to better dissect the genetic basis for ovarian dysfunction and yielded a genetic diagnosis in about 5.0% (6/124) of cases in a cohort of 124 patients with ovarian dysfunction.


Assuntos
Menopausa Precoce , Insuficiência Ovariana Primária , Humanos , Feminino , Insuficiência Ovariana Primária/diagnóstico , Insuficiência Ovariana Primária/genética , Menopausa Precoce/genética , Mutação , Testes Genéticos
14.
Inorg Chem ; 62(2): 653-658, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36594725

RESUMO

Electrocatalytic reduction of NO to NH3 (NORR) emerges as a promising route for achieving harmful NO treatment and sustainable NH3 generation. In this work, we first report that Mo2C is an active and selective NORR catalyst. The developed Mo2C nanosheets deliver a high NH3 yield rate of 122.7 µmol h-1 cm-2 with an NH3 Faradaic efficiency of 86.3% at -0.4 V. Theoretical computations unveil that the surface-terminated Mo atoms on Mo2C can effectively activate NO, promote protonation energetics, and suppress proton adsorption, resulting in high NORR activity and selectivity of Mo2C.

15.
Inorg Chem ; 62(23): 8772-8777, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37253193

RESUMO

We report VB2 as an efficient electrocatalyst for NO-to-NH3 electroreduction (NORR), showing the highest NH3-Faradaic efficiency of 89.6% with the corresponding NH3 yield rate of 198.3 µmol h-1 cm-2 at -0.5 V vs RHE. Theoretical calculations demonstrate that B sites of VB2 act as the key active centers which can facilitate the NORR protonation energetics and inhibit the competitive hydrogen evolution, boosting both NORR activity and selectivity.

16.
Bioorg Chem ; 140: 106781, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37597440

RESUMO

The abnormal activation of the mTOR pathway is closely related to the occurrence and progression of cancer, especially colorectal cancer. In this study, a rational virtual screening strategy has been established and MT-5, a novel mTOR inhibitor with a quinoline scaffold, was obtained from the ChemDiv database. MT-5 showed potent kinase inhibitory activity (IC50: 8.90 µM) and antiproliferative effects against various cancer cell lines, especially HCT-116 cells (IC50: 4.61 µM), and this was 2.2-fold more potent than that of the cisplatin control (IC50: 9.99 µM). Western blot, cell migration, cycle arrest, and apoptosis assays were performed with HCT-116 cells to investigate the potential anticancer mechanism of MT-5. Metabolic stability results in vitro indicated that MT-5 exhibited good stability profiles in artificial gastrointestinal fluids, rat plasma, and liver microsomes. In addition, the key contribution of the residues around the binding pocket of MT-5 in binding to the mTOR protein was also investigated from a computational perspective.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Animais , Ratos , Inibidores de MTOR , Serina-Treonina Quinases TOR , Células HCT116 , Neoplasias Colorretais/tratamento farmacológico
17.
Tohoku J Exp Med ; 259(2): 163-172, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36450479

RESUMO

Proinflammatory cytokines, reactive oxygen species and imbalance of neurotransmitters are involved in the pathophysiology of angiotensin II-induced hypertension. The hypothalamic paraventricular nucleus (PVN) plays a vital role in hypertension. Evidences show that microglia are activated and release proinflammatory cytokines in angiocardiopathy. We hypothesized that angiotensin II induces PVN microglial activation, and the activated PVN microglia release proinflammatory cytokines and cause oxidative stress through nuclear factor-kappa B (NF-κB) pathway, which contributes to sympathetic overactivity and hypertension. Male Sprague-Dawley rats (weight 275-300 g) were infused with angiotensin II to induce hypertension. Then, rats were treated with bilateral PVN infusion of microglial activation inhibitor minocycline, NF-κB activation inhibitor pyrrolidine dithiocarbamate or vehicle for 4 weeks. When compared to control groups, angiotensin II-induced hypertensive rats had higher mean arterial pressure, PVN proinflammatory cytokines, and imbalance of neurotransmitters, accompanied with PVN activated microglia. These rats also had more PVN gp91phox (source of reactive oxygen species production), and NF-κB p65. Bilateral PVN infusion of minocycline or pyrrolidine dithiocarbamate partly or completely ameliorated these changes. This study indicates that angiotensin II-induced hypertensive rats have more activated microglia in PVN, and activated PVN microglia release proinflammatory cytokines and result in oxidative stress, which contributes to sympathoexcitation and hypertensive response. Suppression of activated PVN microglia by minocycline or pyrrolidine dithiocarbamate attenuates inflammation and oxidative stress, and improves angiotensin II-induced hypertension, which indicates that activated microglia promote hypertension through activated NF-κB. The findings may offer hypertension new strategies.


Assuntos
Hipertensão , Minociclina , Ratos , Masculino , Animais , Minociclina/efeitos adversos , Microglia/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Espécies Reativas de Oxigênio/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , NF-kappa B/metabolismo , Angiotensina II/efeitos adversos , Angiotensina II/metabolismo , Ratos Sprague-Dawley , Hipertensão/tratamento farmacológico , Citocinas/metabolismo , Neurotransmissores/efeitos adversos , Neurotransmissores/metabolismo
18.
Int J Mol Sci ; 24(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37628906

RESUMO

Pyrazole derivatives, as a class of heterocyclic compounds, possess unique chemical structures that confer them with a broad spectrum of pharmacological activities. They have been extensively explored for designing potent and selective anticancer agents. In recent years, numerous pyrazole derivatives have been synthesized and evaluated for their anticancer potential against various cancer cell lines. Structure-activity relationship studies have shown that appropriate substitution on different positions of the pyrazole ring can significantly enhance anticancer efficacy and tumor selectivity. It is noteworthy that many pyrazole derivatives have demonstrated multiple mechanisms of anticancer action by interacting with various targets including tubulin, EGFR, CDK, BTK, and DNA. Therefore, this review summarizes the current understanding on the structural features of pyrazole derivatives and their structure-activity relationships with different targets, aiming to facilitate the development of potential pyrazole-based anticancer drugs. We focus on the latest research advances in anticancer activities of pyrazole compounds reported from 2018 to present.


Assuntos
Antineoplásicos , Antineoplásicos/farmacologia , Pirazóis/farmacologia , Linhagem Celular , Relação Estrutura-Atividade , Tubulina (Proteína)
19.
Int J Mol Sci ; 24(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298128

RESUMO

Chemotherapy-induced sarcopenia is an unfavorable prognostic factor implicated in the development of postoperative complications and reduces the quality of life of patients with cancer. Skeletal muscle loss due to cisplatin use is caused by mitochondrial dysfunction and activation of muscle-specific ubiquitin ligases Atrogin-1 and muscle RING finger 1 (MuRF1). Although animal studies suggest the involvement of p53 in age-, immobility-, and denervation-related muscle atrophy, the association between cisplatin-induced atrophy and p53 remains unknown. Herein, we investigated the effect of a p53-specific inhibitor, pifithrin-alpha (PFT-α), on cisplatin-induced atrophy in C2C12 myotubes. Cisplatin increased the protein levels of p53, phosphorylated p53, and upregulated the mRNA expression of p53 target genes PUMA and p21 in C2C12 myotubes. PFT-α ameliorated the increase in intracellular reactive oxygen species production and mitochondrial dysfunction, and also reduced the cisplatin-induced increase in the Bax/Bcl-2 ratio. Although PFT-α also reduced the cisplatin-induced increase in MuRF1 and Atrogin-1 gene expression, it did not ameliorate the decrease in myosin heavy chain mRNA and protein levels and muscle-specific actin and myoglobin protein levels. We conclude that cisplatin increases muscle degradation in C2C12 myotubes in a p53-dependent manner, but p53 has minimal involvement in the reduction of muscle protein synthesis.


Assuntos
Cisplatino , Proteína Supressora de Tumor p53 , Animais , Cisplatino/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Atrofia Muscular/etiologia , Qualidade de Vida , Músculo Esquelético/metabolismo , Fibras Musculares Esqueléticas/metabolismo , RNA Mensageiro/metabolismo
20.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838936

RESUMO

In this study, 2-benzyl-10a-(1H-pyrrol-2-yl)-2,3-dihydropyrazino[1,2-a]indole-1,4,10(10aH)-trione (DHPITO), a previously identified inhibitor against hepatocellular carcinoma cells, is shown to exert its cytotoxic effects by suppressing the proliferation and growth of CRC cells. An investigation of its molecular mechanism confirmed that the cytotoxic activity of DHPITO is mediated through the targeting of microtubules with the promotion of subsequent microtubule polymerisation. With its microtubule-stabilising ability, DHPITO also consistently arrested the cell cycle of the CRC cells at the G2/M phase by promoting the phosphorylation of histone 3 and the accumulation of EB1 at the cell equator, reduced the levels of CRC cell migration and invasion, and induced cellular apoptosis. Furthermore, the compound could suppress both tumour size and tumour weight in a CRC xenograft model without any obvious side effects. Taken together, the findings of the present study reveal the antiproliferative and antitumour mechanisms through which DHPITO exerts its activity, indicating its potential as a putative chemotherapeutic agent and lead compound with a novel structure.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Linhagem Celular Tumoral , Tubulina (Proteína)/metabolismo , Pontos de Checagem do Ciclo Celular , Apoptose , Moduladores de Tubulina/farmacologia , Microtúbulos , Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Proliferação de Células
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