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1.
J Clin Invest ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743490

RESUMO

Impairment of oligodendrocytes and myelin contributes to neurological disorders including multiple sclerosis (MS), stroke and Alzheimer's disease. Regeneration of myelin (remyelination) decreases the vulnerability of demyelinated axons, but this repair process commonly fails with disease progression. A contributor to inefficient remyelination is the altered extracellular matrix (ECM) in lesions that remains to be better defined. We have identified fibulin-2 (FBLN2) as a highly upregulated ECM component in lesions of MS and stroke, and in proteome databases of Alzheimer's disease and traumatic brain injury. Focusing on MS, the inhibitory role of FBLN2 was suggested in the experimental autoimmune encephalomyelitis (EAE) model in which genetic FBLN2 deficiency improved behavioral recovery by promoting the maturation of oligodendrocytes and enhancing remyelination. Mechanistically, when oligodendrocyte progenitors were cultured in differentiation media, FBLN2 impeded their maturation into oligodendrocytes by engaging the Notch pathway, leading to cell death. Adeno-associated virus-deletion of FBLN2 in astrocytes improved oligodendrocyte numbers and functional recovery in EAE and generated new myelin profiles after lysolecithin-induced demyelination. Collectively, our findings implicate FBLN2 as a hitherto unrecognized injury-elevated ECM, and a therapeutic target, that impairs oligodendrocyte maturation and myelin repair.

2.
Transl Cancer Res ; 13(3): 1367-1381, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38617526

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is the most common type and accounts for 90% of all head and neck cancer cases. Despite advances in early diagnosis and treatment strategies-chemotherapy, surgical resection, and radiotherapy-5-year survival remains grim. For patients with early-stage HNSCC, accurately predicting clinical outcomes is challenging. Considering the pivotal role of the immune system in HNSCC, we developed a reliable immune-related gene signature (IRGS) and explored its predictive accuracy in patients with early-stage HNSCC. Methods: We examined immune gene expression profiles and clinical information from 230 early-stage HNSCC specimens, including 100 cases from The Cancer Genome Atlas (TCGA), 49 cases from the Gene Expression Omnibus (GEO; GSE65858), and 81 cases from an independent clinical cohort. The prognostic signature was constructed using Kaplan-Meier analysis and the least absolute shrinkage and selection operator (LASSO) Cox algorithm. We also explored the IRGS-related biological pathways and immune landscape using bioinformatics analysis. Results: A nine-immune-gene signature was generated to significantly stratify patients into high and low-risk groups. High risk patients exhibited shorter survival time [hazard ratio (HR) =13.795, 95% confidence interval (CI): 3.275-58.109, P<0.001]. The signature demonstrated robust prognostic ability in the training and validation sets and could independently predict overall survival (OS) and relapse-free survival (RFS). Subsequently, the receiver operating characteristic (ROC) curve and C-index confirmed the signature's predictive accuracy compared to clinical parameters. Additionally, cases classified as low risk showed more immune cell infiltration than high-risk cases. Conclusions: Our novel IRGS is a reliable and robust classifier for accurate patient stratification and prognostic evaluation. Future studies will attempt to affirm the signature's clinical application to early-stage HNSCC.

3.
Electrophoresis ; 45(9-10): 877-884, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38196015

RESUMO

Macrohaplotype combines multiple types of phased DNA variants, increasing forensic discrimination power. High-quality long-sequencing reads, for example, PacBio HiFi reads, provide data to detect macrohaplotypes in multiploidy and DNA mixtures. However, the bioinformatics tools for detecting macrohaplotypes are lacking. In this study, we developed a bioinformatics software, MacroHapCaller, in which targeted loci (i.e., short TRs [STRs], single nucleotide polymorphisms, and insertion and deletions) are genotyped and combined with novel algorithms to call macrohaplotypes from long reads. MacroHapCaller uses physical phasing (i.e., read-backed phasing) to identify macrohaplotypes, and thus it can detect multi-allelic macrohaplotypes for a given sample. MacroHapCaller was validated with data generated from our designed targeted PacBio HiFi sequencing pipeline, which sequenced ∼8-kb amplicon regions harboring 20 core forensic STR loci in human benchmark samples HG002 and HG003. MacroHapCaller also was validated in whole-genome long-read sequencing data. Robust and accurate genotyping and phased macrohaplotypes were obtained with MacroHapCaller compared with the known ground truth. MacroHapCaller achieved a higher or consistent genotyping accuracy and faster speed than existing tools HipSTR and DeepVar. MacroHapCaller enables efficient macrohaplotype analysis from high-throughput sequencing data and supports applications using discriminating macrohaplotypes.


Assuntos
Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo de Nucleotídeo Único , Poliploidia , Análise de Sequência de DNA , Software , Humanos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Algoritmos , Biologia Computacional/métodos , DNA/genética , DNA/análise , Repetições de Microssatélites/genética , Genética Forense/métodos , Técnicas de Genotipagem/métodos
4.
Neurosci Bull ; 40(2): 255-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37391607

RESUMO

Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.


Assuntos
Imunidade Inata , Macrófagos , Humanos , Cóclea/metabolismo , Cóclea/patologia , Inflamação/metabolismo , Mitocôndrias
5.
FASEB J ; 38(1): e23332, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095232

RESUMO

Severe hypoxia induced by vascular compromise (ovarian torsion, surgery), obliteration of vessels (aging, chemotherapy, particularly platinum drugs) can cause massive follicle atresia. On the other hand, hypoxia increases the occurrence of DNA double-strand breaks (DSBs) and triggers cellular damage repair mechanisms; however, if the damage is not promptly repaired, it can also induce the apoptosis program. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone that plays essential roles in stimulating mammalian follicular development. Here, we report a novel role for IGF-I in protecting hypoxic GCs from apoptosis by promoting DNA repair through the homologous recombination (HR) process. Indeed, the hypoxic environment within follicles significantly inhibited the efficiency of HR-directed DNA repair. The presence of IGF-I-induced HR pathway to alleviate hypoxia-induced DNA damage and apoptosis primarily through upregulating the expression of the RAD51 recombinase. Importantly, we identified a new transcriptional regulator of RAD51, namely E2F8, which mediates the protective effects of IGF-I on hypoxic GCs by facilitating the transcriptional activation of RAD51. Furthermore, we demonstrated that the PI3K/AKT pathway is crucial for IGF-I-induced E2F8 expression, resulting in increased RAD51 expression and enhanced HR activity, which mitigates hypoxia-induced DNA damage and thereby protects against GCs apoptosis. Together, these findings define a novel mechanism of IGF-I-mediated GCs protection by activating the HR repair through the PI3K/AKT/E2F8/RAD51 pathway under hypoxia.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Reparo de DNA por Recombinação , Feminino , Animais , Suínos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Insulin-Like I/genética , Reparo do DNA , Recombinação Homóloga , Rad51 Recombinase/genética , Hipóxia , Células da Granulosa/metabolismo , Apoptose , Mamíferos/metabolismo
6.
J Agric Food Chem ; 71(49): 19705-19716, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38029323

RESUMO

Our previous study with artificial intelligence (AI)-assisted screening found that diosmin, a natural flavonoid extracted from citrus, may affect myoblast proliferation and differentiation. At present, few studies have been conducted regarding the biological function of diosmin in muscle cells. Here, using molecular biological techniques, we found that diosmin elevated the proliferation ability of C2C12 myoblasts via activating the Akt/FOXO1 pathway to promote FOXO1 nuclear export, thus repressing p27 protein expression, increasing CDK2, CDK4, and cyclin D1 and cyclin E1 protein expression and accelerating cell cycle transformation, which contributed to myogenesis. Moreover, diosmin suppressed differentiation of C2C12 myoblasts by delaying the terminal exit of the cell cycle in early differentiated myoblasts and inhibiting autophagic flux in mature myotubes. Furthermore, diosmin promoted myogenesis by activating the Akt/FOXO1 pathway to facilitate myoblast proliferation, which had a positive biological effect on the repair of muscle injury. This study revealed the effect and mechanism of diosmin on skeletal muscle cells and simultaneously provided a new candidate drug for the treatment of myopathy.


Assuntos
Diosmina , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diosmina/metabolismo , Diosmina/farmacologia , Inteligência Artificial , Proliferação de Células , Mioblastos , Diferenciação Celular , Desenvolvimento Muscular
7.
ACS Infect Dis ; 9(7): 1319-1333, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37348028

RESUMO

Flavivirus infections, such as those caused by dengue virus (DENV), West Nile virus (WNV), yellow fever virus (YFV), and Zika virus (ZIKV), pose a rising threat to global health. There are no FDA-approved drugs for flaviviruses, although a small number of flaviviruses have vaccines. For flaviviruses or unknown viruses that may appear in the future, it is particularly desirable to identify broad-spectrum inhibitors. The NS5 protein is regarded as one of the most promising flavivirus drug targets because it is conserved across flaviviruses. In this study, we used FL-NAH, a fluorescent analog of the methyl donor S-adenosyl methionine (SAM), to develop a fluorescence polarization (FP)-based high throughput screening (HTS) assay to specifically target methyltransferase (MTase), a vital enzyme for flaviviruses that methylates the N7 and 2'-O positions of the viral 5'-RNA cap. Pilot screening identified two candidate MTase inhibitors, NSC 111552 and 288387. The two compounds inhibited the FL-NAH binding to the DENV3 MTase with low micromolar IC50. Functional assays verified the inhibitory potency of these molecules for the flavivirus MTase activity. Binding studies indicated that these molecules are bound directly to the DENV3 MTase with similar low micromolar affinity. Furthermore, we showed that these compounds greatly reduced ZIKV replication in cell-based experiments at dosages that did not cause cytotoxicity. Finally, docking studies revealed that these molecules bind to the SAM-binding region on the DENV3 MTase, and further mutagenesis studies verified residues important for the binding of these compounds. Overall, these compounds are innovative and attractive candidates for the development of broad-spectrum inhibitors for the treatment of flavivirus infections.


Assuntos
Infecções por Flavivirus , Flavivirus , Infecção por Zika virus , Zika virus , Humanos , Metiltransferases/metabolismo , Zika virus/genética , Sítios de Ligação
8.
Cell Oncol (Dordr) ; 46(5): 1493-1507, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37219768

RESUMO

Cisplatin (CDDP)-based chemotherapy is commonly used to treat advanced non-small cell lung cancer (NSCLC). However, the efficacy is limited by the development of drug resistance. Tripartite motif (TRIM) proteins typically have E3 ubiquitin ligase activities and modulate protein stability. In the present study, we screened for chemosensitivity-regulating TRIM proteins using CDDP-resistant NSCLC cell lines. We show that TRIM17 is upregulated in CDDP-resistant NSCLC cells and tumors compared to CDDP-sensitive counterparts. NSCLC patients with high TRIM17 expression in tumors have shorter progression-free survival than those with low TRIM17 expression after CDDP chemotherapy. Knockdown of TRIM17 increases the sensitivity of NSCLC cells to CDDP both in vitro and in vivo. In contrast, overexpression of TRIM17 promotes CDDP resistance in NSCLC cells. TRIM17-mediated CDDP resistance is associated with attenuation of reactive oxygen species (ROS) production and DNA damage. Mechanistically, TRIM17 interacts with RBM38 and promotes K48-linked ubiquitination and degradation of RBM38. TRIM17-induced CDDP resistance is remarkably reversed by RBM38. Additionally, RBM38 enhances CDDP-induced production of ROS. In conclusion, TRIM17 upregulation drives CDDP resistance in NSCLC largely by promoting RBM38 ubiquitination and degradation. Targeting TRIM17 may represent a promising strategy for improving CDDP-based chemotherapy in NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ubiquitinação , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/farmacologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
9.
Dig Dis Sci ; 68(7): 3070-3082, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36680650

RESUMO

BACKGROUND: Ferroptosis, as a unique form of cell death, plays crucial negative roles in tumorigenesis and progression. This study aimed to investigate the role and molecular mechanism of TEA domain transcription factor 1 (TEAD1) in HCC and its effect on sorafenib-induced ferroptosis. METHODS: TEAD1 expression was analyzed in HCC tissues using quantitative PCR, and western blot. The effects on cell proliferation, migration and invasion were determined by CCK-8, wound healing and Transwell assays. Intracellular iron, reactive oxygen species (ROS), malondialdehyde (MDA) and GSH measurement was used to assess ferroptosis. Chromatin immunoprecipitation and luciferase reporter gene assays were performed to verify the relationship between TEAD1 and solute carrier family 3 member 2 (SLC3A2). Expression of mTOR, ribosomal protein S6, glutathione peroxidase 4 (GPX4) and SLC3A2 was analyzed by western blot. Tumor xenografts were used assess the effect of TEAD1 on tumor growth in vivo. RESULTS: TEAD1 was more abundant in HCC compared with normal tissues. Overexpression of TEAD1 enhanced the proliferation, migration, and invasion of HCC cells, while knockdown of TEAD1 inhibited these cell behaviors. Further, TEAD1 inhibited ferroptosis, which was demonstrated by decreased intracellular Fe2+ content, ROS, and MDA levels, and increased GSH activity. Mechnistically, TEAD1 promotes the transcription of SLC3A2 and activates the mTOR signaling. Additionally, silenced TEAD1 restrained tumor growth and enhance sorafenib-induced antitumor activity in vivo. CONCLUSIONS: TEAD1 confers resistance of HCC cells to ferroptosis, thereby promoting the progression of HCC, suggesting the potential value of TEAD1 in the diagnosis and treatment of HCC.


Assuntos
3,4-Metilenodioxianfetamina , Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Espécies Reativas de Oxigênio , Sorafenibe/farmacologia , Fatores de Transcrição de Domínio TEA
10.
J Agric Food Chem ; 71(1): 499-511, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36563293

RESUMO

Neoruscogenin is a plant-origin sapogenin that has the potential to modulate muscle growth among the small-molecule compounds that we previously predicted by artificial intelligence to target myostatin (MSTN). This study aimed to elucidate the biological role of neoruscogenin on muscle growth and its relationship with MSTN. Using molecular biological techniques, we found that neoruscogenin inhibited MSTN maturation, thereby repressing its signal transduction; further facilitated protein synthesis metabolism and reduced protein degradation metabolism, ultimately promoting the differentiation of myoblasts and hypertrophy of muscle fibers; and had the effect of repairing muscle injury. This study enriched the biological functions of neoruscogenin and provided a theoretical basis for the treatment of human myopathy and its application in the livestock industry.


Assuntos
Miostatina , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Miostatina/genética , Miostatina/metabolismo , Inteligência Artificial , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Hipertrofia , Músculo Esquelético/metabolismo
11.
Front Genet ; 13: 952649, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910201

RESUMO

Single-cell RNA-sequencing (scRNA-seq) technologies enable the measurements of gene expressions in individual cells, which is helpful for exploring cancer heterogeneity and precision medicine. However, various technical noises lead to false zero values (missing gene expression values) in scRNA-seq data, termed as dropout events. These zero values complicate the analysis of cell patterns, which affects the high-precision analysis of intra-tumor heterogeneity. Recovering missing gene expression values is still a major obstacle in the scRNA-seq data analysis. In this study, taking the cell heterogeneity into consideration, we develop a novel method, called single cell Gauss-Newton Gene expression Imputation (scGNGI), to impute the scRNA-seq expression matrices by using a low-rank matrix completion. The obtained experimental results on the simulated datasets and real scRNA-seq datasets show that scGNGI can more effectively impute the missing values for scRNA-seq gene expression and improve the down-stream analysis compared to other state-of-the-art methods. Moreover, we show that the proposed method can better preserve gene expression variability among cells. Overall, this study helps explore the complex biological system and precision medicine in scRNA-seq data.

12.
Ann Palliat Med ; 11(7): 2464-2477, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35927780

RESUMO

BACKGROUND: Phase I clinical trials play an important role in the follow-up clinical trials and even the drug registration and marketing. However, the screening success ratio in phase I clinical trials is low, and the screening process of the trials consumes a significant amount of human and material resources, but the results are unsatisfactory. At present, there is no large sample data analysis for screening failure in phase I clinical trials. It is therefore urgent to find the reasons for screening failure in phase I clinical trials. METHODS: A total of 1,058 healthy volunteers who failed the screening in 11 phase I clinical trials were retrospectively collected from October 2018 to June 2021 in Cangzhou Central Hospital. Data on all participants who failed screening for the study were analyzed (descriptive analysis) and reasons for their non-randomization were classified, as well as the differences of main screening failures between four years. RESULTS: A total of 1,466 healthy volunteers were enrolled in the 11 trials, and among them 1,058 subjects failed the screening. The total screening success ratio of our study was only 27.8%, the highest being 38.5% and the lowest being 18.2%. The top 3 reasons for non-randomization were abnormalities in blood biochemistry tests (23.3%), vital sign examination (19.3%), and electrocardiogram (ECG) (16.6%). Abnormal blood biochemistry was the main reason between 2019 and 2021, except for 2018 in which it was the second reason. CONCLUSIONS: Screening failure is a burdensome issue which various clinical trial sites must contend with. Investigators can still take some effective measures by strengthening the in-depth understanding of informed consent, paying attention to the quality of test samples, a correcting definition of no clinical significance (NCS). Also, low-cost and non-invasive examinations can be arranged first to better protect the volunteers and reduce the screening costs of clinical trials. To our delight, we find people's attention to the annual physical examination may help to screen healthy volunteers. Overall, this study shows that it is crucial and professional to develop a screening plan to minimize the resultant impact on timelines and budgets of phase I clinical trials enrolling healthy volunteers.


Assuntos
Voluntários Saudáveis , Consentimento Livre e Esclarecido , Programas de Rastreamento , Ensaios Clínicos Fase I como Assunto , Humanos , Seleção de Pacientes , Estudos Retrospectivos
13.
Front Pharmacol ; 13: 827710, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928272

RESUMO

Background: Leukopenia is one of the side effects of radiotherapy and chemotherapy. Diyushengbai tablet (DYT) is used to prevent and treat leukopenia caused by various reasons. A meta-analysis was performed to systematically analyze the therapeutic effects of DYT on preventing and treating leukopenia caused by radiotherapy and chemotherapy. Objectives: This study aimed to systematically evaluate the efficacy and safety of DYT in preventing and treating leukopenia caused by radiotherapy and chemotherapy. Methods: We performed a comprehensive literature search of electronic databases such as PubMed, The Cochrane Library, China Knowledge Network (CNKI), China Biomedical Literature Database (CBM), Wanfang Data Knowledge Service Platform, and VIP, through November of 2021. The scanning reports deadline is until November 2021. The bias risk evaluation criteria developed by the Cochrane collaborative organization were used to evaluate the literature quality of the included studies. The RevMan5.4 software was used to analyze the data, and the Stata16.0 was used to perform the Egger test. Results: After selecting all the databases, a total of 41 reports which involved 3,793 cases were analyzed. Meta-analysis showed that DYT could significantly reduce the white blood cell (WBC) suppression caused by radiotherapy and chemotherapy and improve the patients' WBC counts and neutrophils, compared with the efficacy of other oral WBC-elevating drugs such as Leucogen tablets and Batilol tablets and additional utilization of granulocyte colony-stimulating factor (G-CSF). The results of meta-analysis showed that for preventive medication purpose, the overall incidence of leukocyte suppression was [RR = 0.74, 95%CI (0.59, 0.92), p = 0.006], and the white blood cell count was [MD = 1.12, 95%CI (0.95, 1.29), p < 0.00001]; while for therapeutic purpose, the incidence of overall leukocyte suppression was [RR = 0.61, 95%CI (0.38, 0.95), p = 0.03], and the white blood cell count was [MD = 1.20, 95%CI (0.77, 1.62), p < 0.00001]. More importantly, the additional use of DYT can reduce the application amount of G-CSF. The results showed that the application of G-CSF can be reduced by an average of 1.57 from the beginning of treatment to return normal white blood cells around 2.23 in two cycles of chemotherapy. Conclusion: DYT is more effective in preventing and treating leukopenia caused by radiotherapy and chemotherapy than other oral WBC-elevating drugs, which have a high clinical value.

14.
Acta Pharm Sin B ; 12(4): 1662-1670, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35847519

RESUMO

Zika virus (ZIKV) causes significant human diseases without specific therapy. Previously we found erythrosin B, an FDA-approved food additive, inhibited viral NS2B-NS3 interactions, leading to inhibition of ZIKV infection in cell culture. In this study, we performed pharmacokinetic and in vivo studies to demonstrate the efficacy of erythrosin B against ZIKV in 3D mini-brain organoid and mouse models. Our results showed that erythrosin B is very effective in abolishing ZIKV replication in the 3D organoid model. Although pharmacokinetics studies indicated that erythrosin B had a low absorption profile, mice challenged by a lethal dose of ZIKV showed a significantly improved survival rate upon oral administration of erythrosin B, compared to vehicle control. Limited structure-activity relationship studies indicated that most analogs of erythrosin B with modifications on the xanthene ring led to loss or reduction of inhibitory activities towards viral NS2B-NS3 interactions, protease activity and antiviral efficacy. In contrast, introducing chlorine substitutions on the isobenzofuran ring led to slightly increased activities, suggesting that the isobenzofuran ring is well tolerated for modifications. Cytotoxicity studies indicated that all derivatives are nontoxic to human cells. Overall, our studies demonstrated erythrosin B is an effective antiviral against ZIKV both in vitro and in vivo.

15.
Antiviral Res ; 205: 105381, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35835291

RESUMO

SARS-CoV-2 has raised the alarm to search for effective therapy for this virus. To date several vaccines have been approved but few available drugs reported recently still need approval from FDA. Remdesivir was approved for emergency use only. In this report, the SARS-CoV-2 3CLpro was expressed and purified. By using a FRET-based enzymatic assay, we have screened a library consisting of more than 300 different niclosamide derivatives and identified three molecules JMX0286, JMX0301, and JMX0941 as potent allosteric inhibitors against SARS-CoV-2 3CLpro, with IC50 values similar to that of known covalent inhibitor boceprevir. In a cell-based antiviral assay, these inhibitors can inhibit the virus growth with EC50 in the range of 2-3 µM. The mechanism of action of JMX0286, JMX0301, and JMX0941 were characterized by enzyme kinetics, affinity binding and protein-based substrate digestion. Molecular docking, molecular dynamics (MD) simulations and hydration studies suggested that JMX0286, JMX0301, JMX0941 bind specifically to an allosteric pocket of the SARS-CoV-2 3CL protease. This study provides three potent compounds for further studies.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Antivirais/química , Antivirais/farmacologia , Proteases 3C de Coronavírus , Cisteína Endopeptidases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais
16.
J Agric Food Chem ; 70(26): 8097-8110, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35729769

RESUMO

In mammals, a vast majority of ovarian follicles undergo atresia, which is caused by granulosa cell (GC) apoptosis. GCs in follicles are exposed to low oxygen. Hypoxia triggers reactive oxygen species (ROS) generation, which leads to cell oxidative stress and apoptosis. Sulforaphane (SFN), a phytochemical isothiocyanate enriched in cruciferous vegetables, has exhibited a crucial role in mitigating oxidative stress. To explore the effect of SFN on porcine GC apoptosis in a hypoxic environment, we handled the established hypoxia model (1% O2) of cultured porcine GCs with SFN. Results showed that SFN rescued hypoxia-induced apoptosis and viability of GCs. Meanwhile, SFN increased the expression of antioxidant enzymes and reduced the accumulation of ROS in GC cytoplasm and mitochondria under hypoxia. Mechanically, SFN activated the transcription factor of redox-sensitive nuclear factor-erythroid 2-related factor 2 (NFE2L2) entering the nucleus, further inducing mitophagy and increased antioxidant capacity, finally alleviating the adverse effect of hypoxia on porcine GCs. In conclusion, SFN inhibited hypoxia-evoked GC apoptosis by activating antioxidant defenses and mitophagy through NFE2L2. New targets may be provided for regulating follicular development and atresia by these findings.


Assuntos
Antioxidantes , Mitofagia , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Feminino , Células da Granulosa , Hipóxia/metabolismo , Isotiocianatos/metabolismo , Isotiocianatos/farmacologia , Mamíferos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Sulfóxidos/metabolismo , Suínos
17.
Pathogens ; 11(3)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35335617

RESUMO

Flaviviruses cause a significant amount of mortality and morbidity, especially in regions where they are endemic. A recent example is the outbreak of Zika virus throughout the world. Development of antiviral drugs against different viral targets is as important as the development of vaccines. During viral replication, a single polyprotein precursor (PP) is produced and further cleaved into individual proteins by a viral NS2B-NS3 protease complex together with host proteases. Flavivirus protease is one of the most attractive targets for development of therapeutic antivirals because it is essential for viral PP processing, leading to active viral proteins. In this review, we have summarized recent development in drug discovery targeting the NS2B-NS3 protease of flaviviruses, especially Zika, dengue, and West Nile viruses.

18.
Front Mol Biosci ; 9: 821146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211511

RESUMO

Multidrug-resistant pathogens are of significant concern in recent years. Hence new antifungal and anti-bacterial drug targets are urgently needed before the situation goes beyond control. Inteins are polypeptides that self-splice from exteins without the need for cofactors or external energy, resulting in joining of extein fragments. Inteins are present in many organisms, including human pathogens such as Mycobacterium tuberculosis, Cryptococcus neoformans, C. gattii, and Aspergillus fumigatus. Because intein elements are not present in human genes, they are attractive drug targets to develop antifungals and antibiotics. Thus far, a few inhibitors of intein splicing have been reported. Metal-ions such as Zn2+ and Cu2+, and platinum-containing compound cisplatin inhibit intein splicing in M. tuberculosis and C. neoformans by binding to the active site cysteines. A small-molecule inhibitor 6G-318S and its derivative 6G-319S are found to inhibit intein splicing in C. neoformans and C. gattii with a MIC in nanomolar concentrations. Inteins have also been used in many other applications. Intein can be used in activating a protein inside a cell using small molecules. Moreover, split intein can be used to deliver large genes in experimental gene therapy and to kill selected species in a mixed population of microbes by taking advantage of the toxin-antitoxin system. Furthermore, split inteins are used in synthesizing cyclic peptides and in developing cell culture model to study infectious viruses including SARS-CoV-2 in the biosafety level (BSL) 2 facility. This mini-review discusses the recent research developments of inteins in drug discovery and therapeutic research.

19.
Chemistry ; 28(5): e202103142, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34897851

RESUMO

An investigation of pulsed-laser-ablated Zn, Cd and Hg metal atom reactions with HCN under excess argon during co-deposition with laser-ablated Hg atoms from a dental amalgam target also provided Hg emissions capable of photoionization of the CN photo-dissociation product. A new band at 1933.4 cm-1 in the region of the CN and CN+ gas-phase fundamental absorptions that appeared upon annealing the matrix to 20 K after sample deposition, and disappeared upon UV photolysis is assigned to (Ar)n CN+ , our key finding. It is not possible to determine the n coefficient exactly, but structure calculations suggest that one, two, three or four argon atoms can solvate the CN+ cation in an argon matrix with C-N absorptions calculated (B3LYP) to be between 2317.2 and 2319.8 cm-1 . Similar bands were observed in solid krypton at 1920.5, in solid xenon at 1935.4 and in solid neon at 1947.8 cm-1 . H13 CN reagent gave an 1892.3 absorption with shift instead, and a 12/13 isotopic frequency ratio-nearly the same as found for 13 CN+ itself in the gas phase and in the argon matrix. The CN+ molecular ion serves as a useful infrared probe to examine Ng clusters. The following ion reactions are believed to occur here: the first step upon sample deposition is assisted by a focused pulsed YAG laser, and the second step occurs on sample annealing: (Ar)2 + +CN→Ar+CN+ →(Ar)n CN+ .

20.
Drug Deliv ; 28(1): 2108-2118, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34607478

RESUMO

To treat various cancers, including lung cancer, chemotherapy requires the systematic administering of chemotherapy. The chemotherapeutic effectiveness of anticancer drugs has been enhanced by polymer nanoparticles (NPs), according to new findings. As an outcome, we have developed biodegradable triblock poly(ethylene glycol)-poly(ε-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) polymeric NPs for the co-delivery of sorafenib (SORA) and crizotinib (CRIZ) and investigated their effect on lung cancer by in vitro and in vivo. There is little polydispersity in the SORA-CRIZ@NPs, an average size of 30.45 ± 2.89 nm range. A steady release of SORA and CRIZ was observed, with no burst impact. The apoptosis rate of SORA-CRIZ@NPs was greater than that of free drugs in 4T1 and A549 cells. Further, in vitro cytotoxicity of the polymeric NPs loaded with potential anticancer drugs was more quickly absorbed by cancer cells. On the other hand, compared to free drugs (SORA + CRIZ), SORA + CRIZ@NPs showed a substantial reduction of tumor development, longer survival rate, and a lowered side effect when delivered intravenously to nude mice xenograft model with 4T1 cancer cells. TUNEL positivity was also increased in tumor cells treated with SORA-CRIZ@NPs, demonstrating the therapeutic effectiveness. SORA-CRIZ@NPs might be used to treat lung cancer soon, based on the results from our new findings.


Assuntos
Antineoplásicos/farmacologia , Crizotinibe/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Sorafenibe/farmacologia , Células A549 , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Crizotinibe/administração & dosagem , Portadores de Fármacos/química , Combinação de Medicamentos , Liberação Controlada de Fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos Nus , Polímeros/química , Sorafenibe/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
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