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1.
PLoS Genet ; 18(9): e1010395, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36166470

RESUMO

Programmed Cell Death (PCD) or apoptosis is a highly conserved biological process and plays essential roles both in the development and stress context. In Drosophila, expression of pro-apoptotic genes, including reaper (rpr), head involution defective (hid), grim, and sickle (skl), is sufficient to induce cell death. Here, we demonstrate that the chromatin remodeler Dmp18, the homolog of mammalian Znhit1, plays a crucial role in regulating apoptosis in eye and wing development. We showed that loss of Dmp18 disrupted eye and wing development, up-regulated transcription of pro-apoptotic genes, and induced apoptosis. Inhibition of apoptosis suppressed the eye defects caused by Dmp18 deletion. Furthermore, loss of Dmp18 disrupted H2Av incorporation into chromatin, promoted H3K4me3, but reduced H3K27me3 modifications on the TSS regions of pro-apoptotic genes. These results indicate that Dmp18 negatively regulates apoptosis by mediating H2Av incorporation and histone H3 modifications at pro-apoptotic gene loci for transcriptional regulation. Our study uncovers the role of Dmp18 in regulating apoptosis in Drosophila eye and wing development and provides insights into chromatin remodeling regulating apoptosis at the epigenetic levels.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Apoptose/genética , Cromatina/genética , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Histonas/genética , Discos Imaginais/metabolismo , Mamíferos/genética
2.
Proc Natl Acad Sci U S A ; 119(26): e2122805119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35733260

RESUMO

During viral infection, sensing of viral RNA by retinoic acid-inducible gene-I-like receptors (RLRs) initiates an antiviral innate immune response, which is mediated by the mitochondrial adaptor protein VISA (virus-induced signal adaptor; also known as mitochondrial antiviral signaling protein [MAVS]). VISA is regulated by various posttranslational modifications (PTMs), such as polyubiquitination, phosphorylation, O-linked ß-d-N-acetylglucosaminylation (O-GlcNAcylation), and monomethylation. However, whether other forms of PTMs regulate VISA-mediated innate immune signaling remains elusive. Here, we report that Poly(ADP-ribosyl)ation (PARylation) is a PTM of VISA, which attenuates innate immune response to RNA viruses. Using a biochemical purification approach, we identified tankyrase 1 (TNKS1) as a VISA-associated protein. Viral infection led to the induction of TNKS1 and its homolog TNKS2, which translocated from cytosol to mitochondria and interacted with VISA. TNKS1 and TNKS2 catalyze the PARylation of VISA at Glu137 residue, thereby priming it for K48-linked polyubiquitination by the E3 ligase Ring figure protein 146 (RNF146) and subsequent degradation. Consistently, TNKS1, TNKS2, or RNF146 deficiency increased the RNA virus-triggered induction of downstream effector genes and impaired the replication of the virus. Moreover, TNKS1- or TNKS2-deficient mice produced higher levels of type I interferons (IFNs) and proinflammatory cytokines after virus infection and markedly reduced virus loads in the brains and lungs. Together, our findings uncover an essential role of PARylation of VISA in virus-triggered innate immune signaling, which represents a mechanism to avoid excessive harmful immune response.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Imunidade Inata , Infecções por Vírus de RNA , Vírus de RNA , Tanquirases , Ubiquitina-Proteína Ligases , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Células HEK293 , Humanos , Imunidade Inata/genética , Camundongos , Infecções por Vírus de RNA/imunologia , Vírus de RNA/imunologia , Tanquirases/genética , Tanquirases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
3.
Small ; 20(23): e2307337, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38152926

RESUMO

Nanostructures formed from the self-assembly of amino acids are promising materials in many fields, especially for biomedical applications. However, their low stability resulting from the weak noncovalent interactions between the amino acid building blocks limits their use. In this work, nanoparticles co-assembled by fluorenylmethoxycarbonyl (Fmoc)-protected tyrosine (Fmoc-Tyr-OH) and tryptophan (Fmoc-Trp-OH) are crosslinked by ultraviolet (UV) light irradiation. Two methods are investigated to induce the dimerization of tyrosine, irradiating at 254 nm or at 365 nm in the presence of riboflavin as a photo-initiator. For the crosslinking performed at 254 nm, both Fmoc-Tyr-OH and Fmoc-Trp-OH generate dimers. In contrast, only Fmoc-Tyr-OH participates in the riboflavin-mediated dimerization under irradiation at 365 nm. The participation of both amino acids in forming the dimers leads to more stable crosslinked nanoparticles, allowing also to perform further chemical modifications for cancer applications. The anticancer drug doxorubicin (Dox) is adsorbed onto the crosslinked nanoparticles, subsequently coated by a tannic acid-iron complex, endowing the nanoparticles with glutathione-responsiveness and photothermal properties, allowing to control the release of Dox. A remarkable anticancer efficiency is obtained in vitro and in vivo in tumor-bearing mice thanks to the combined chemo- and photothermal treatment.


Assuntos
Aminoácidos , Doxorrubicina , Nanopartículas , Nanopartículas/química , Aminoácidos/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Animais , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Camundongos , Terapia Fototérmica/métodos , Linhagem Celular Tumoral , Raios Ultravioleta , Reagentes de Ligações Cruzadas/química
4.
Bioorg Med Chem ; 107: 117760, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38762978

RESUMO

Oncolytic peptides represented potential novel candidates for anticancer treatments especially drug-resistant cancer cell lines. One of the most promising and extensively studied is LTX-315, which is considered as the first in class oncolytic peptide and has entered phase I/II clinical trials. Nevertheless, the shortcomings including poor proteolytic stability, moderate anticancer durability and high synthesis costs may hinder the widespread clinical applications of LTX-315. In order to reduce the synthesis costs, as well as develop derivatives possessing both high protease-stability and durable anticancer efficiency, twenty LTX-315-based derived-peptides were designed and efficiently synthesized. Especially, through solid-phase S-alkylation, as well as the optimized peptide cleavage condition, the derived peptides could be prepared with drastically reduced synthesis cost. The in vitro anticancer efficiency, serum stability, anticancer durability, anti-migration activity, and hemolysis effect were systematically investigated. It was found that derived peptide MS-13 exhibited comparable anticancer efficiency and durability to those of LTX-315. Strikingly, the D-type peptide MS-20, which is the enantiomer of MS-13, was demonstrated to possess significantly high proteolytic stability and sustained anticancer durability. In general, the cost-effective synthesis and stability-guided structural optimizations were conducted on LTX-315, affording the highly hydrolysis resistant MS-20 which possessed durable anticancer activity. Meanwhile, this study also provided a reliable reference for the future optimization of anticancer peptides through the solid-phase S-alkylation and L-type to D-type amino acid substitutions.


Assuntos
Antineoplásicos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Estrutura-Atividade , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Movimento Celular/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/síntese química , Hemólise/efeitos dos fármacos , Oligopeptídeos
5.
Bioorg Chem ; 147: 107356, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604021

RESUMO

Developing "turn on" fluorescent probes was desirable for the detection of the effective anticoagulant agent heparin in clinical applications. Through combining the aggregation induced emission (AIE) fluorogen tetraphenylethene (TPE) and heparin specific binding peptide AG73, the promising "turn on" fluorescent probe TPE-1 has been developed. Nevertheless, although TPE-1 could achieve the sensitive and selective detection of heparin, the low proteolytic stability and undesirable poor solubility may limit its widespread applications. In this study, seven TPE-1 derived fluorescent probes were rationally designed, efficiently synthesized and evaluated. The stability and water solubility were systematically estimated. Especially, to achieve real-time monitoring of proteolytic stability, the novel Abz/Dnp-based "turn on" probes that employ the internally quenched fluorescent (IQF) mechanism were designed and synthesized. Moreover, the detection ability of synthetic fluorescent probes for heparin were systematically evaluated. Importantly, the performance of d-type peptide fluorescent probe XH-6 indicated that d-type amino acid substitutions could significantly improve the proteolytic stability without compromising its ability of heparin sensing, and attaching solubilizing tag 2-(2-aminoethoxy) ethoxy) acid (AEEA) could greatly enhance the solubility. Collectively, this study not only established practical strategies to improve both the water solubility and proteolytic stability of "turn on" fluorescent probes for heparin sensing, but also provided valuable references for the subsequent development of enzymatic hydrolysis-resistant d-type peptides based fluorescent probes.


Assuntos
Corantes Fluorescentes , Heparina , Peptídeos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Heparina/análise , Heparina/química , Peptídeos/química , Peptídeos/síntese química , Estrutura Molecular , Humanos , Espectrometria de Fluorescência
6.
J Nanobiotechnology ; 22(1): 275, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778401

RESUMO

BACKGROUND: Acute gouty is caused by the excessive accumulation of Monosodium Urate (MSU) crystals within various parts of the body, which leads to a deterioration of the local microenvironment. This degradation is marked by elevated levels of uric acid (UA), increased reactive oxygen species (ROS) production, hypoxic conditions, an upsurge in pro-inflammatory mediators, and mitochondrial dysfunction. RESULTS: In this study, we developed a multifunctional nanoparticle of polydopamine-platinum (PDA@Pt) to combat acute gout by leveraging mild hyperthermia to synergistically enhance UA degradation and anti-inflammatory effect. Herein, PDA acts as a foundational template that facilitates the growth of a Pt shell on the surface of its nanospheres, leading to the formation of the PDA@Pt nanomedicine. Within this therapeutic agent, the Pt nanoparticle catalyzes the decomposition of UA and actively breaks down endogenous hydrogen peroxide (H2O2) to produce O2, which helps to alleviate hypoxic conditions. Concurrently, the PDA component possesses exceptional capacity for ROS scavenging. Most significantly, Both PDA and Pt shell exhibit absorption in the Near-Infrared-II (NIR-II) region, which not only endow PDA@Pt with superior photothermal conversion efficiency for effective photothermal therapy (PTT) but also substantially enhances the nanomedicine's capacity for UA degradation, O2 production and ROS scavenging enzymatic activities. This photothermally-enhanced approach effectively facilitates the repair of mitochondrial damage and downregulates the NF-κB signaling pathway to inhibit the expression of pro-inflammatory cytokines. CONCLUSIONS: The multifunctional nanomedicine PDA@Pt exhibits exceptional efficacy in UA reduction and anti-inflammatory effects, presenting a promising potential therapeutic strategy for the management of acute gout.


Assuntos
Gota , Indóis , Polímeros , Espécies Reativas de Oxigênio , Ácido Úrico , Gota/tratamento farmacológico , Gota/metabolismo , Gota/terapia , Espécies Reativas de Oxigênio/metabolismo , Animais , Camundongos , Polímeros/química , Indóis/química , Indóis/farmacologia , Nanopartículas/química , Platina/química , Platina/farmacologia , Platina/uso terapêutico , Humanos , Peróxido de Hidrogênio/metabolismo , Hipertermia Induzida/métodos , Células RAW 264.7 , Terapia Fototérmica/métodos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Masculino
7.
BMC Pulm Med ; 24(1): 62, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287299

RESUMO

BACKGROUND: Lung ultrasound (LUS) score could quantitatively reflect the lung aeration, which has been well applied in critically ill patients. The aim of the systematic review and meta-analysis was to evaluate the association between LUS score at admission and the risk of in-hospital mortality of adults with acute respiratory distress syndrome (ARDS). METHODS: Toachieve the objective of this meta-analysis, we conducted a thorough search of PubMed, Embase, Cochrane Library, and the Web of Science to identify relevant observational studies with longitudinal follow-up. We employed random-effects models to combine the outcomes, considering the potential influence of heterogeneity. RESULTS: Thirteen cohort studies with 1,022 hospitalized patients with ARDS were included. Among them, 343 patients (33.6%) died during hospitalization. The pooled results suggested that the LUS score at admission was higher in non-survivors as compared to survivors (standardized mean difference = 0.73, 95% confidence interval [CI]: 0.55 to 0.91, p < 0.001; I2 = 25%). Moreover, a high LUS score at admission was associated with a higher risk of in-hospital mortality of patients with ARDS (risk ratio: 1.44, 95% CI: 1.14 to 1.81, p = 0.002; I2 = 46%). Subgroup analyses showed consistent results in studies with LUS score analyzed with 12 or 16 lung regions, and in studies reporting mortality during ICU or within 1-month hospitalization. CONCLUSION: Our findings suggest that a high LUS score at admission may be associated with a high risk of in-hospital mortality of patients with ARDS.


Assuntos
Pulmão , Síndrome do Desconforto Respiratório , Adulto , Humanos , Mortalidade Hospitalar , Prognóstico , Pulmão/diagnóstico por imagem , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Estudos de Coortes , Ultrassonografia/métodos , Estudos Observacionais como Assunto
8.
Artigo em Inglês | MEDLINE | ID: mdl-39019667

RESUMO

BACKGROUND: The rate of distant metastasis in patients with pancreatic neuroendocrine tumors (PNETs) is 20%-50% at the time of initial diagnosis. However, whether tumor size can predict distant metastasis for PNETs remains unknown up to date. METHODS: We used Surveillance, Epidemiology, and End Results (SEER) population-based data to collect 6089 patients with PNETs from 2010 to 2019. The optimal cut-off point of tumor size to predict distant metastasis was calculated by Youden's index. Multivariate logistic regression analysis was used to figure out the association between tumor size and distant metastasis patterns. RESULTS: The most common metastatic site was liver (27.2%), followed by bone (3.0%), lung (2.3%) and brain (0.4%). Based on an optimal cut-off value of tumor size (25.5 mm) for predicting distant metastasis determined by Youden's index, patients were categorized into groups of tumor size < 25.5 mm and ≥ 25.5 mm. Multivariate logistic regression analyses showed that, compared with < 25.5 mm, tumor size ≥ 25.5 mm was an independent risk predictor of overall distant metastasis [odds ratio (OR) = 4.491, 95% confidence interval (CI): 3.724-5.416, P < 0.001] and liver metastasis (OR = 4.686, 95% CI: 3.886-5.651, P < 0.001). CONCLUSIONS: Tumor size ≥ 25.5 mm was significantly associated with more overall distant and liver metastases. Timely identification of distant metastasis for tumor size ≥ 25.5 mm may provide survival benefit for timely and precise treatment.

9.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732979

RESUMO

Accurate measurement of coal gas permeability helps prevent coal gas safety accidents effectively. To predict permeability more accurately, we propose the IDBO-BPNN coal body gas permeability prediction model. This model combines the Improved Dung Beetle algorithm (IDBO) with the BP neural network (BPNN). First, the Sine chaotic mapping, Osprey optimization algorithm, and adaptive T-distribution dynamic selection strategy are integrated to enhance the DBO algorithm and improve its global search capability. Then, IDBO is utilized to optimize the weights and thresholds in BPNN to enhance its prediction accuracy and mitigate the risk of overfitting to some extent. Secondly, based on the influencing factors of gas permeability, effective stress, gas pressure, temperature, and compressive strength, they are chosen as the coupling indicators. The SPSS 27 software is used to analyze the correlation among the indicators using the Pearson correlation coefficient matrix. Additionally, the Kernel Principal Component Analysis (KPCA) is employed to extract the original data. Then, the original data is divided into principal component data for the model input. The prediction results of the IDBO-BPNN model are compared with those of the PSO-BPNN, PSO-LSSVM, PSO-SVM, MPA-BPNN, WOA-SVM, BES-SVM, and DPO-BPNN models. This comparison assesses the capability of KPCA to enhance the accuracy of model predictions and the performance of the IDBO-BPNN model. Finally, the IDBO-BPNN model is tested using data from a coal mine in Shanxi. The results indicate that the predicted outcome closely aligns with the actual value, confirming the reliability and stability of the model. Therefore, the IDBO-BPNN model is better suited for predicting coal gas permeability in academic research writing.

10.
Cell Tissue Bank ; 25(2): 663-676, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38383908

RESUMO

To investigate the efficacy of mesenchymal stromal cells in the treatment of type 1 diabetes. Articles about the effects of mesenchymal stromal cells for T1D were retrieved in PubMed, Web of Science, Embase, and the Cochrane Library databases up to July 2023. Additional relevant studies were manually searched through citations. HbA1c, FBG, PBG, insulin requirement and C-peptide were assessed. The risk of bias was evaluated with the ROB 2.0 and ROBINS-I tools. Six RCTs and eight nRCTs were included. Of the 14 studies included, two evaluated BM-MSCs, three evaluated UC-MSCs, five evaluated AHSCT, two evaluated CB-SCs, and two evaluated UC-SCs plus aBM-MNCs. At the end of follow-up, ten studies found that mesenchymal stromal cells improved glycemic outcomes in T1D, while the remaining four studies showed no significant improvement. Findings support the positive impacts observed from utilizing mesenchymal stromal cells in individuals with T1D. However, the overall methodological quality of the identified studies and findings is heterogeneous, limiting the interpretation of the therapeutic benefits of mesenchymal stromal cells in T1D. Methodically rigorous research is needed to further increase credibility.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Diabetes Mellitus Tipo 1/terapia , Humanos , Células-Tronco Mesenquimais/citologia , Resultado do Tratamento , Glicemia/metabolismo
11.
J Am Chem Soc ; 145(22): 12255-12263, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37246940

RESUMO

Chiral metal nanoclusters have recently been attracting great attention. It is challenging to realize asymmetric catalysis via atomically precise metal nanoclusters. Herein, we report the synthesis and total structure determination of chiral clusters [Au7Ag8(dppf)3(l-/d-proline)6](BF4)2 (l-/d-Au7Ag8). Superatomic clusters l-/d-Au7Ag8 display intense and mirror-image Cotton effects in their CD spectra. Density functional theory (DFT) calculations were carried out to understand the correlation between electronic structures and the optical activity of the enantiomeric pair. Surprisingly, the incorporation of proline in a metal nanocluster can significantly promote the catalytic efficiency in asymmetric Aldol reactions. The increase of catalytic activity of Au7Ag8 in comparison with organocatalysis by proline is attributed to the cooperative effect of the metal core and prolines, showing the advantages of the integration of metal catalysis and organocatalysis in a metal nanocluster.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37133916

RESUMO

A Gram-stain-negative, facultative anaerobic, motile, rod-shaped and orange bacterium, designated A06T, was obtained off the coast of Weihai, PR China. Cells were 0.4-0.5×0.6-1.0 µm in size. Strain A06T grew at 20-40 °C (optimum, 33 °C), at pH 6.0-8.0 (optimum, pH 6.5-7.0) and in the presence of 0-8 % NaCl (w/v) (optimum, 2 %). Cells were oxidase and catalase positive. Menaquinone-7 was detected as the major respiratory quinone. The dominant cellular fatty acids were identified as C15:0 2-OH, iso-C15:0, anteiso-C15:0 and iso-C15:1 ω6c. The DNA G+C content of strain A06T was 46.1 mol%. The polar lipids were phosphatidylethanolamine, one aminolipid, one glycolipid and three unidentified lipids. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain A06T is a member of the family Prolixibacteraceae and exhibited the highest sequence similarity to Mangrovibacterium diazotrophicum DSM 27148T (94.3 %). Based on its phylogenetic and phenotypic characteristics, strain A06T is considered to represent a novel genus in the family Prolixibacteraceae, for which the name Gaoshiqia gen. nov. is proposed. The type species is Gaoshiqia sediminis sp. nov., with type strain A06T (=KCTC 92029T=MCCC 1H00491T). The identification and acquisition of microbial species and genes in sediments will help broaden the understanding of microbial resources and lay a foundation for its application in biotechnology. Strain A06T uses an enrichment method, so the isolation of strain A06T is of great significance to the enrichment of marine microbial resources.


Assuntos
Ácidos Graxos , Sedimentos Geológicos , Ácidos Graxos/química , Sedimentos Geológicos/microbiologia , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , China
13.
Bioorg Chem ; 138: 106674, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37331169

RESUMO

Nitrogen mustards (NMs) are an important class of chemotherapeutic drugs and have been widely employed for the treatment of various cancers. However, due to the high reactivity of nitrogen mustard, most NMs react with proteins and phospholipids within the cell membrane. Therefore, only a very small fraction of NMs can reach the reach nucleus, alkylating and cross-linking DNA. To efficiently penetrate the cell membrane barrier, the hybridization of NMs with a membranolytic agent may be an effective strategy. Herein, the chlorambucil (CLB, a kind of NM) hybrids were first designed by conjugation with membranolytic peptide LTX-315. However, although LTX-315 could help large amounts of CLB penetrate the cytomembrane and enter the cytoplasm, CLB still did not readily reach the nucleus. Our previous work demonstrated that the hybrid peptide NTP-385 obtained by covalent conjugation of rhodamine B with LTX-315 could accumulate in the nucleus. Hence, the NTP-385-CLB conjugate, named FXY-3, was then designed and systematically evaluated both in vitro and in vivo. FXY-3 displayed prominent localization in the cancer cell nucleus and induced severe DNA double-strand breaks (DSBs) to trigger cell apoptosis. Especially, compared with CLB and LTX-315, FXY-3 exhibited significantly increased in vitro cytotoxicity against a panel of cancer cell lines. Moreover, FXY-3 showed superior in vivo anticancer efficiency in the mouse cancer model. Collectively, this study established an effective strategy to increase the anticancer activity and the nuclear accumulation of NMs, which will provide a valuable reference for future nucleus-targeting modification of nitrogen mustards.


Assuntos
Neoplasias , Compostos de Mostarda Nitrogenada , Animais , Camundongos , Clorambucila/farmacologia , DNA/metabolismo , Nitrogênio , Compostos de Mostarda Nitrogenada/farmacologia , Peptídeos/farmacologia
14.
Bioorg Chem ; 134: 106451, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907048

RESUMO

Cytotoxic peptides derived from spider venoms have been considered as promising candidates for anticancer treatment. The novel cell penetrating peptide LVTX-8, which is a 25-residue amphipathic α-helical peptide isolated from spider Lycosa vittata, exhibited potent cytotoxicity and is a potential precursor for further anticancer drug development. Nevertheless, LVTX-8 may be easily degraded by multiple proteases, inducing the proteolytic stability problem and short half-life. In this study, ten LVTX-8-based analogs were rationally designed and the efficient manual synthetic method was established by the DIC/Oxyma based condensation system. The cytotoxicity of synthetic peptides was systematically evaluated against seven cancer cell lines. Seven of the derived peptides exhibited high cytotoxicity towards tested cancer in vitro, which was better than or comparable to that of natural LVTX-8. In particular, both N-acetyl and C-hydrazide modified LVTX-8 (825) and the conjugate methotrexate (MTX)-GFLG-LVTX-8 (827) possessed more durable anticancer efficiency, higher proteolytic stability, as well as lower hemolysis. Finally, we confirmed that LVTX-8 could disrupt the integrity of cell membrane, target the mitochondria and reduce the mitochondrial membrane potential to induce the cell death. Taken together, the structural modifications were conducted on LVTX-8 for the first time and the stability significantly improved derivatives 825 and 827 may provide useful references for the modifications of cytotoxic peptides.


Assuntos
Antineoplásicos , Peptídeos Penetradores de Células , Neoplasias , Venenos de Aranha , Humanos , Venenos de Aranha/farmacologia , Venenos de Aranha/química , Venenos de Aranha/metabolismo , Antineoplásicos/farmacologia , Metotrexato/química , Peptídeos Penetradores de Células/química
15.
Acta Pharmacol Sin ; 44(1): 201-210, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35794372

RESUMO

The use of oncolytic peptides with activity against a wide range of cancer entities as a new and promising cancer therapeutic strategy has drawn increasing attention. The oncolytic peptide LTX-315 derived from bovine lactoferricin (LfcinB) was found to be highly effective against suspension cancer cells, but not adherent cancer cells. In this study, we tactically fused LTX-315 with rhodamine B through a hybridization strategy to design and synthesize a series of nucleus-targeting hybrid peptides and evaluated their activity against adherent cancer cells. Thus, four hybrid peptides, NTP-212, NTP-217, NTP-223 and NTP-385, were synthesized. These hybrid peptides enhanced the anticancer activity of LTX-315 in a panel of adherent cancer cell lines by 2.4- to 37.5-fold. In model mice bearing B16-F10 melanoma xenografts, injection of NTP-385 (0.5 mg per mouse for 3 consecutive days) induced almost complete regression of melanoma, prolonged the median survival time and increased the overall survival. Notably, the administered dose of NTP-385 was only half the effective dose of LTX-315. We further revealed that unlike LTX-315, which targets the mitochondria, NTP-385 disrupted the nuclear membrane and accumulated in the nucleus, resulting in the transfer of a substantial amount of reactive oxygen species (ROS) from the cytoplasm to the nucleus through the fragmented nuclear membrane. This ultimately led to DNA double-strand break (DSB)-mediated intrinsic apoptosis. In conclusion, this study demonstrates that hybrid peptides obtained from the fusion of LTX-315 and rhodamine B enhance anti-adherent cancer cell activity by targeting the nucleus and triggering DNA DSB-mediated intrinsic apoptosis. This study also provides an advantageous reference for nucleus-targeting peptide modification.


Assuntos
Melanoma , Peptídeos , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Apoptose , DNA
16.
Zhonghua Nan Ke Xue ; 29(7): 625-629, 2023 Jul.
Artigo em Zh | MEDLINE | ID: mdl-38619410

RESUMO

OBJECTIVE: To explore and analyze the correlation between anxiety levels, coping strategies, and fertility quality of life in male soldiers with infertility. METHODS: A questionnaire survey was conducted on 480 male soldiers with infertility who visited the Reproductive Medicine Department of the Eastern Theater Command General Hospital from June 2022 to February 2023, analyze the impact of anxiety levels on stress coping strategies and fertility quality of life in male officers and soldiers with infertility. RESULTS: Self evaluation scale score is (43.06 ± 15.02), Fertility Quality of Life Scale score is (52.11 ± 36.68), Trait Coping Style Questionnaire score is (48.45 ± 23.15). The relevant analysis results show that there is a negative correlation between the scores of the Self Rating Anxiety Scale and the Reproductive Quality of Life Scale, a positive correlation between the scores of the Self Rating Anxiety Scale and the Trait Coping Style Questionnaire, and a positive correlation between the scores of the Reproductive Quality of Life Scale and the Trait Coping Style Questionnaire. The results of multiple regression analysis showed that years of infertility, history of childbirth, anxiety level, and coping strategies entered the regression equation. The anxiety level of male officers and soldiers with infertility has a mediating effect on the relationship between stress coping styles and quality of life during childbirth. CONCLUSION: The mental health status of male officers and soldiers with infertility is poor, and their coping strategies and quality of life during childbirth are at a moderate to low level. This indicates that more attention should be paid to the special group of male officers and soldiers with infertility, and psychological intervention should be strengthened in routine treatment. Provide support from different perspectives to address concerns and enhance the combat effectiveness of the military.


Assuntos
Infertilidade , Militares , Masculino , Humanos , Capacidades de Enfrentamento , Qualidade de Vida , Fertilidade , Ansiedade
17.
Neuroimage ; 264: 119766, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36435344

RESUMO

Predictions, the bridge between the internal and external worlds, are established by prior experience and updated by sensory stimuli. Responses to omitted but unexpected stimuli, known as omission responses, can break the one-to-one mapping of stimulus-response and can expose predictions established by the preceding stimulus built up. While research into exogenous predictions (driven by external stimuli) is often reported, that into endogenous predictions (driven by internal percepts) is rarely available in the literature. Here, we report evidence for endogenous predictions established by the Zwicker tone illusion, a phantom pure-tone-like auditory percept following notch noises. We found that MMN, P300, and theta oscillations could be recorded using an omission paradigm in subjects who can perceive Zwicker tone illusions, but could not in those who cannot. The MMN and P300 responses relied on attention, but theta oscillations did not. In-depth analysis shows that an increase in single-trial theta power, including total and induced theta, with the endogenous prediction, is lateralized to the left frontal brain areas. Our study depicts that the brain automatically analyzes internal perception, progressively establishes predictions and yields prediction errors in the left frontal region when a violation occurs.


Assuntos
Ilusões , Humanos , Ilusões/fisiologia , Som , Atenção/fisiologia , Córtex Cerebral/fisiologia , Lobo Frontal/fisiologia , Estimulação Acústica , Percepção Auditiva/fisiologia , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia
18.
Microb Pathog ; 172: 105766, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36087689

RESUMO

Streptococcus suis (S. suis) is an important zoonotic pathogen that can cause high morbidity and mortality in both humans and swine. As the most important life-threatening infection of the central nervous system (CNS), meningitis is an important syndrome of S. suis infection. The vancomycin resistance associated sensor/regulator (VraSR) is a critical two-component signal transduction system that affects the ability of S. suis to resist the host innate immune system and promotes its ability to adhere to brain microvascular endothelial cells (BMECs). Prior work also found mice infected with ΔvraSR had no obvious neurological symptoms, unlike mice infected with wild-type SC19. Whether and how VraSR participates in the development of S. suis meningitis remains unknown. Here, we found ΔvraSR-infected mice did not show obvious meningitis, compared with wild-type SC19-infected mice. Moreover, the proinflammatory cytokines and chemokines in serum and brains of ΔvraSR-infected mice, including IL-6, TNF-α, MCP-1 and IFN-γ, were significantly lower than wild-type infected group. Besides, blood-brain barrier (BBB) permeability also confirmed that the mutant had lower ability to disrupt BBB. Furthermore, in vivo and in vitro experiments showed that SC19 could increase BBB permeability by downregulating tight junction (TJ) proteins such as ZO-1, ß-Catenin, Occludin, and Clauidn-5, compared with mutant ΔvraSR. These findings provide new insight into the influence of S. suis VraSR on BBB disruption during the pathogenic process of streptococcal meningitis, thereby offering potential targets for future preventative and therapeutic strategies against this disease.


Assuntos
Meningites Bacterianas , Infecções Estreptocócicas , Streptococcus suis , Humanos , Animais , Camundongos , Suínos , Streptococcus suis/metabolismo , Barreira Hematoencefálica/metabolismo , beta Catenina/metabolismo , Células Endoteliais/metabolismo , Resistência a Vancomicina , Ocludina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Meningites Bacterianas/metabolismo , Infecções Estreptocócicas/metabolismo , Transdução de Sinais/fisiologia , Citocinas/metabolismo , Proteínas de Junções Íntimas/metabolismo , Quimiocinas/metabolismo
19.
Fish Shellfish Immunol ; 127: 521-529, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35792347

RESUMO

The root of Scutellaria baicalensis (Scutellaria Radix) has been used as herbal medicine for years in China; however, its stem and leaf (aerial part) are considered as waste. The water extract of aerial part of S. baicalensis, named as SBA, having anti-microbial property has been applied in fish aquaculture. To extend the usage of SBA in fish feeding, SBA was employed to feed pearl gentian grouper (a hybrid of Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂), and subsequently the total fish output, the levels of digestive enzymes and inflammatory cytokines were determined. Feeding the fish with different doses of SBA for two months, the body length and weight were significantly increased by 5%-10%. In parallel, the expressions of alkaline phosphatase and growth-related factors in bone, liver and muscle of SBA-fed fish were doubled, which could account the growth promoting effect of SBA. Besides, the activity of digestive enzyme, lipase, and the expressions of anti-inflammatory cytokines were markedly stimulated by 2-3 times under the feeding of 3% SBA-containing diet. The results indicated the growth promoting activity of SBA in culture of pearl gentian grouper, as well as the effect of SBA in strengthening the immunity. These beneficial effects of SBA feeding can increase the total yield of pearl gentian grouper in aquaculture. Thus, the re-cycle of waste products during the farming of S. baicalensis herb in serving as fish feeding should be encouraged.


Assuntos
Bass , Ração Animal/análise , Animais , Citocinas/genética , Suplementos Nutricionais/análise , Componentes Aéreos da Planta , Scutellaria baicalensis
20.
J Pept Sci ; 28(11): e3428, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35610021

RESUMO

Discovering new antibiotics with novel chemical scaffolds and antibacterial mechanisms presents a challenge for medicinal scientists worldwide as the ever-increasing bacterial resistance poses a serious threat to human health. A new cyclic peptide-based antibiotic termed teixobactin was discovered from a screen of uncultured soil bacteria through iChip technology in 2015. Teixobactin exhibits excellent antibacterial activity against all the tested gram-positive pathogens and Mycobacterium tuberculosis, including drug-resistant strains. Given that teixobactin targets the highly conserved lipid II and lipid III, which induces the simultaneous inhibition of both peptidoglycan and teichoic acid synthesis, the emergence of resistance is considered to be rather difficult. The novel structure, potent antibacterial activity, and highly conservative targets make teixobactin a promising lead compound for further antibiotic development. This review provides a comprehensive treatise on the advances of teixobactin in the areas of discovery processes, antibacterial activity, mechanisms of action, chemical synthesis, and structural optimizations. The synthetic methods for the key building block l-allo-End, natural teixobactin, representative teixobactin analogs, as well as the structure-activity relationship studies will be highlighted and discussed in details. Finally, some insights into new trends for the generation of novel teixobactin analogs and tips for future work and directions will be commented.


Assuntos
Infecções Bacterianas , Depsipeptídeos , Mycobacterium tuberculosis , Antibacterianos/química , Antibacterianos/farmacologia , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Peptidoglicano , Solo , Relação Estrutura-Atividade
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