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1.
Insect Mol Biol ; 33(1): 17-28, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37707297

RESUMO

In insects, vitellogenin (Vg) is generally viewed as a female-specific protein. Its primary function is to supply nutrition to developing embryos. Here, we reported Vg from the male adults of a natural predator, Chrysopa pallens. The male Vg was depleted by RNAi. Mating with Vg-deficient male downregulated female Vg expression, suppressed ovarian development and decreased reproductive output. Whole-organism transcriptome analysis after male Vg knockdown showed no differential expression of the known spermatogenesis-related regulators and seminal fluid protein genes, but a sharp downregulation of an unknown gene, which encodes a testis-enriched big protein (Vcsoo). Separate knockdown of male Vg and Vcsoo disturbed the assembly of spermatid cytoplasmic organelles in males and suppressed the expansion of ovary germarium in mated females. These results demonstrated that C. pallens male Vg signals through the downstream Vcsoo and regulates male and female reproduction.


Assuntos
Testículo , Vitelogeninas , Feminino , Masculino , Animais , Vitelogeninas/genética , Vitelogeninas/metabolismo , Insetos/genética , Reprodução , Gametogênese
2.
Dement Geriatr Cogn Disord ; 53(3): 107-118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574473

RESUMO

INTRODUCTION: The objective of the study was to explore the molecular mechanism of long noncoding RNA (lncRNA) LINC00472 in Alzheimer's disease (AD) and identify potential novel targets for AD therapy. METHOD: Ferroptosis-related lncRNAs were screened by GEO database. AD mouse model was constructed for in vivo experiments. The content of Aß protein and tau protein hyperphosphorylation were examined in hippocampal tissue samples of mice. Subsequently, HT22 cells were induced with Aß25-35 to establish a neuronal injury model of AD in vitro. The expression of FOXO1, a key gene for ferroptosis, was verified by overexpressing/knocking down the LINC00472. The effects of LINC00472 on ROS and lipid peroxidation content, GPX4, and tau protein in AD model cells were examined by ROS assay, MDA assay, Western blot, and qRT-PCR. Subsequently, the expression of iron ion, FTH, TfRC, and Fpn protein were detected in AD cells. RESULTS: The level of FOXO1 was positively correlated with the degree of AD. In vivo experiments showed that the expression of Aß and tau hyperphosphorylated were significantly reduced in the inhibitor group and iron was significantly reduced relative to the AD group. In the AD cell model, the content of lipid peroxide was upregulated, GPX4 protein and mRNA were decreased, and phosphorylation of tau protein was enhanced in the AD cell model relative to the control group. Whereas knocking down LINC00472 inhibited the upregulation of lipid peroxide, decreased the level of GPX4, and enhanced tau protein phosphorylation, and reduced iron accumulation in AD cells. CONCLUSIONS: LINC00472 affects ferroptosis in AD by regulating iron accumulation in neuronal cells.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Ferroptose , Proteína Forkhead Box O1 , Neurônios , RNA Longo não Codificante , Proteínas tau , Ferroptose/fisiologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , Camundongos , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Neurônios/metabolismo , Peptídeos beta-Amiloides/metabolismo , Proteínas tau/metabolismo , Proteínas tau/genética , Humanos , Hipocampo/metabolismo , Masculino , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Espécies Reativas de Oxigênio/metabolismo , Peroxidação de Lipídeos/fisiologia , Camundongos Endogâmicos C57BL
3.
Mol Pharm ; 20(12): 6262-6271, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37948165

RESUMO

Cancer is one of the greatest threats to human health due to late diagnosis and incomplete resection. The bimodal probe combines positron emission tomography (PET) imaging for noninvasive whole-body scanning with intraoperative near-infrared fluorescence (NIRF) surgical guidance for preoperative tumor detection, tumor resection during surgery, and postoperative monitoring. We developed a new PET/NIRF bimodal imaging agent, [68Ga]Ga-DOTA-NPC, covalently coupled to DCDSTCY and DOTA via ethylenediamine and radiolabeled with gallium-68, and investigated it in vitro and in vivo. The probe was found to be preferential for colon cancer cells due to the organic anion-transporting polypeptide1B3 (OATP1B3). PET/NIRF imaging allowed us to confirm [68Ga]Ga-DOTA-NPC as a promising probe for tumor detection, as it provides good biosafety and high-contrast tumor accumulation. Orthotopic and subcutaneous colon tumors were successfully resected under real-time NIRF guidance. [68Ga]Ga-DOTA-NPC provides highly sensitive and unlimited tissue-penetrating PET/NIRF imaging, helping to visualize and differentiate tumors from adjacent tissue.


Assuntos
Radioisótopos de Gálio , Neoplasias , Humanos , Fluorescência , Tomografia por Emissão de Pósitrons/métodos , Neoplasias/patologia , Compostos Radiofarmacêuticos , Linhagem Celular Tumoral
4.
Analyst ; 148(7): 1579-1586, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36892478

RESUMO

Nanozymes, a class of catalytic nanomaterials, have shown great potential to substitute natural enzymes in various applications. Nevertheless, the pursuit of high-efficiency peroxidase-like activity in a wide pH range is one of the major challenges existing in designing nanozymes. A feasible strategy is to construct an artificial active center by using porous materials as stable supporting structures, which can actively modulate biocatalytic activities via their porous atomic structures and more active sites. Herein, a gold nanoparticles/metal-organic framework (MOF) heterostructure was prepared using UiO-66 as a stable support structure (Au NPs/UiO-66), which demonstrates enhanced peroxidase-like activity, ∼8.95 times higher than that of pure Au NPs. Strikingly, Au NPs/UiO-66 exhibits excellent stability (maintains above 80% activity at 40-70 °C and retains 93% activity after 3 months of storage) and sustained high relative activity (above 90%) over a pH range of 5.0-9.0 due to the homogeneous dispersibility of free-ligand Au NPs and the strong chemical interaction between the Au NPs and the UiO-66 host. Moreover, a colorimetric assay of ascorbic acid (AA) and three AA-related biological enzymes was developed based on Au NPs/UiO-66 nanozyme, which has a good linear detection range and excellent anti-interference ability. This work provides important guidance for the expansion of metal NPs/MOF heterostructure nanozymes and their application prospects in the development of biosensors.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Ácido Ascórbico/análise , Estruturas Metalorgânicas/química , Ouro/química , Nanopartículas Metálicas/química , Peroxidases , Concentração de Íons de Hidrogênio , Peróxido de Hidrogênio
5.
Bull Entomol Res ; 113(1): 49-62, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35904166

RESUMO

Understanding predator-prey interactions is essential for successful pest management by using predators, especially for the suppression of novel invasive pest. The green lacewing Chrysopa formosa is a promising polyphagous predator that is widely used in the biocontrol of various pests in China, but information on the control efficiency of this predator against the seriously invasive pest Spodoptera frugiperda and native Spodoptera litura is limited. Here we evaluated the predation efficiency of C. formosa adults on eggs and first- to third-instar larvae of S. frugiperda and S. litura through functional response experiments and determined the consumption capacity and prey preference of this chrysopid. Adults of C. formosa had a high consumption of eggs and earlier instar larvae of both prey species, and displayed a type II functional response on all prey stages. Attack rates of the chrysopid on different prey stages were statistically similar, but the handling time increased notably as the prey developed. The highest predation efficiency and shortest-handling time were observed for C. formosa feeding on Spodoptera eggs, followed by the first-instar larvae. C. formosa exhibited a significant preference for S. litura over S. frugiperda in a two-prey system. In addition, we summarized the functional response and predation efficiency of several chrysopids against noctuid pests and made a comparison with the results obtained from C. formosa. These results indicate that C. formosa has potential as an agent for biological control of noctuid pests, particularly for the newly invasive pest S. frugiperda in China.


Assuntos
Controle Biológico de Vetores , Comportamento Predatório , Animais , Spodoptera/fisiologia , Taiwan , Larva/fisiologia , Comportamento Predatório/fisiologia
6.
J Integr Plant Biol ; 65(5): 1262-1276, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36534453

RESUMO

Seed dormancy is an important agronomic trait in crops, and plants with low dormancy are prone to preharvest sprouting (PHS) under high-temperature and humid conditions. In this study, we report that the GATA transcription factor TaGATA1 is a positive regulator of seed dormancy by regulating TaABI5 expression in wheat. Our results demonstrate that TaGATA1 overexpression significantly enhances seed dormancy and increases resistance to PHS in wheat. Gene expression patterns, abscisic acid (ABA) response assay, and transcriptome analysis all indicate that TaGATA1 functions through the ABA signaling pathway. The transcript abundance of TaABI5, an essential regulator in the ABA signaling pathway, is significantly elevated in plants overexpressing TaGATA1. Chromatin immunoprecipitation assay (ChIP) and transient expression analysis showed that TaGATA1 binds to the GATA motifs at the promoter of TaABI5 and induces its expression. We also demonstrate that TaGATA1 physically interacts with the putative demethylase TaELF6-A1, the wheat orthologue of Arabidopsis ELF6. ChIP-qPCR analysis showed that H3K27me3 levels significantly decline at the TaABI5 promoter in the TaGATA1-overexpression wheat line and that transient expression of TaELF6-A1 reduces methylation levels at the TaABI5 promoter, increasing TaABI5 expression. These findings reveal a new transcription module, including TaGATA1-TaELF6-A1-TaABI5, which contributes to seed dormancy through the ABA signaling pathway and epigenetic reprogramming at the target site. TaGATA1 could be a candidate gene for improving PHS resistance.


Assuntos
Fatores de Transcrição GATA , Triticum , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição GATA/genética , Regulação da Expressão Gênica de Plantas , Germinação , Dormência de Plantas/genética , Sementes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/genética
7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(9): 1304-1315, 2023.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38044641

RESUMO

OBJECTIVES: Tubal factor infertility severely impairs the natural fertility of women, and there is for genuine tubal recanalization, including restoration of both the anatomy and function of the diseased fallopian tubes. Currently, there is no effective treatment available. This study aims to explore methods for promoting the repair and recanalization of fallopian tubes from these 2 aspects. METHODS: Apelin-13 sustained-release microspheres and poly (lactic-co-glycolic acid) (PLGA) three-dimensional (3D) biodegradable scaffolds were prepared. The basic characteristics and in vivo degradation (mass loss rate) of the biodegradable scaffolds were tested, along with the in vitro drug release (cumulative release rate), the in vivo drug release (Apelin-13 plasma concentration), and in vitro degradation (degradation rate) of the microspheres. The Apelin-13 microspheres (microsphere group)/PLGA 3D scaffolds loaded with Apelin-13 sustained-release microspheres (scaffold-microcapsule group) were injected/placed into the fallopian tubes of New Zealand rabbit of chronic salpingitis models. The patency, microscopic structure, and positive expression of estrogen receptor and progesterone receptor of the fallopian tubes in the control group, the model group, the microcapsule group, and the scaffold-microcapsule group was observed and compared. RESULTS: At the 4th week post-operation, the mass loss rate of the PLGA 3D scaffolds, the degradation rate of the microspheres, and the Apelin-13 sustained-release microspheres-generated cumulative release rate in vitro over 30 days were 98.66%, 70.58%, and 98.68% respectively. The plasma concentration of Apelin-13 reached its peak within 5 days and remained stable for 25 days. Compared with the model and microsphere groups, the scaffold-microsphere group showed a milder inflammatory reaction within the tubal lumen, a higher rate of fallopian tube patency, and higher expression levels of estrogen and progesterone receptors (all P<0.05). The indicators of the scaffold-microsphere group were close to those of the control group. CONCLUSIONS: The PLGA 3D scaffolds loaded with Apelin-13 sustained-release microspheres can comprehensively repair the anatomical structure and physiological function of the fallopian tubes and hold promise for truly effective tubal recanalization.


Assuntos
Ácido Láctico , Ácido Poliglicólico , Coelhos , Feminino , Humanos , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico/química , Preparações de Ação Retardada , Tubas Uterinas , Cápsulas
8.
Anal Chem ; 94(32): 11255-11263, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35921653

RESUMO

Multimodality imaging recognized as a promising monitoring strategy can serve the needs of accurate diagnosis and treatment of cancer by providing molecular and anatomic information about tumor sites. However, the probes based on multiple imaging modalities for surgery navigation remain limited due to poor biocompatibility and tumor targeting specificity. Herein, we present a small-molecule near-infrared fluorescence/magnetic resonance (NIRF/MR) imaging probe, Gd-NMC-3, covalently coupled with DCDSTCY and Gd-DOTA via butane diamine, for precise detection and intraoperative visualization. The in vitro and in vivo studies demonstrated that Gd-NMC-3 could be effectively accumulated in tumor sites as a bimodal imaging molecule exhibiting significant fluorescence accumulation and reasonable relaxation property in tumors with low cytotoxicity and good biocompatibility. Furthermore, Gd-NMC-3 was successfully applied to provide real-time visual navigation in LM3 orthotopic and subcutaneous tumor models to guide the resection of tumors. Importantly, no more fluorescence was observed in mice after operation, implying the total removal of tumor tissues. In conclusion, Gd-NMC-3 has great potential to be applied in the clinic based on its high resolution and sensitivity in tumor imaging.


Assuntos
Imageamento por Ressonância Magnética , Sondas Moleculares , Animais , Linhagem Celular Tumoral , Imageamento por Ressonância Magnética/métodos , Camundongos , Imagem Molecular , Imagem Multimodal , Imagem Óptica
9.
Hum Reprod ; 37(8): 1727-1738, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35690928

RESUMO

STUDY QUESTION: Can we identify diurnal oscillations in human semen parameters as well as peak times of semen quality? SUMMARY ANSWER: Human semen parameters show substantial diurnal oscillation, with most parameters reaching a peak between 1100 and 1500 h. WHAT IS KNOWN ALREADY: A circadian clock appears to regulate different physiological functions in various organs, but it remains controversial whether diurnal rhythms occur in human semen parameters. STUDY DESIGN, SIZE, DURATION: The medical record of a provincial human sperm bank (HSB) with 33 430 semen samples collected between 0800 and 1700 h from 1 March 2010 to 8 July 2015 was used to analyze variation in semen parameters among time points. A laboratory study was conducted to collect semen samples (n = 36) from six volunteers at six time points with identical time intervals (2 days plus 4 h) between 6 June and 8 July in 2019, in order to investigate the diurnal oscillation of semen parameters in vivo, with a strictly controlled abstinence period. Therefore, the sperm bank study with a large sample size and the in vivo study with a strictly controlled abstinence period in a 24-h time window could be compared to describe the diurnal rhythms in human semen parameters. PARTICIPANTS/MATERIALS, SETTING, METHODS: Samples were obtained from potential HSB donors and from participants in the laboratory study who were volunteers, recruited by flyers distributed in the community. Total sperm count, sperm concentration, semen volume, progressive motility and total motility were assessed using computer-aided sperm analysis. In addition, sperm chromatin integrity parameters (DNA fragmentation index and high DNA stainability) were assessed by the sperm chromatin structure assay, and sperm viability was measured with flow cytometry in the laboratory study. MAIN RESULTS AND THE ROLE OF CHANCE: The 33 430 samples from the HSB showed a temporal variation in total sperm count, sperm concentration, semen volume, progressive motility and total motility (all P < 0.001) between 0800 and 1700 h. Consequently, the eligibility of semen samples for use in ART, based on bank standards, fluctuated with time point. Each hour earlier/later than 1100 h was associated with 1.14-fold risk of ineligibility. Similarly, the 36 samples taken during the 24-h time window showed diurnal oscillation. With the pre-collection abstinence period strictly controlled, most semen parameters reached the most favorable level between 1100 and 1500 h. LIMITATIONS, REASONS FOR CAUTION: Some of the possible confounding factors, such as energy intake, which might influence semen quality or diurnal rhythms, were not adjusted for in the analyses. In addition, the findings should be considered with caution because the study was conducted in a specific population, time and place, while the timing of oscillations could differ with changing conditions. WIDER IMPLICATIONS OF THE FINDINGS: The findings could help us to estimate semen quality more precisely and to obtain higher quality sperm for use in ART and in natural conception. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Natural Science Foundation of China (81871208) and National Key R&D Program of China (2017YFC1002001). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Análise do Sêmen , Sêmen , Cromatina , Ritmo Circadiano , Humanos , Masculino , Sêmen/fisiologia , Bancos de Esperma , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia
10.
Chem Rec ; 22(10): e202200092, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35641414

RESUMO

Carbon-based materials have been successfully applied in the zinc ion batteries to improve the energy storage capability and durability of zinc anodes. In this review, four types of carbon materials (conventional carbons, fiber-like carbons, carbon nanotubes, graphene and other 2D carbon materials) are introduced based on the electrode preparation, physicochemical property and battery performance. Several modification strategies are also illustrated, such as heteroatom doping, hierarchical design and metal/carbon composites. Besides the discussion of existing issues of zinc anodes, the structure-performance relationships are analyzed in depth. Finally, conclusive remarks of this review are summarized and prospects of the future improvement are proposed.

11.
J Obstet Gynaecol Res ; 48(1): 230-238, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34788897

RESUMO

OBJECTIVE: To examine the prevalence and factors associated with early resumption of sexual intercourse among postnatal women in China. METHOD: We conducted a retrospective multicenter study of 15 834 postpartum women from 60 hospitals in 15 different locations across China. Data were obtained from questionnaires administered to the participants. All dates were analyzed using a one-way ANOVA and two-level Cox multiple linear regression models. RESULTS: More than half of the participating women (55.9%) resumed sexual intercourse by 3 months postpartum. The independent variables associated with the postpartum resumption of sexual intercourse included sociodemographic characteristics (age, geographic location, educational attainment) and medical histories, including the previous abortion (incorporate with spontaneous and voluntary abortion) frequency, menstrual recovery, exclusive breastfeeding, and number of living children (p < 0.05). CONCLUSION: More than half of the women in this study resumed sexual intercourse within 3 months postpartum. Women with a lower educational attainment and from the western regions of China were more likely to resume sexual intercourse earlier. Increasing age, delayed recovery of menses, and exclusive breastfeeding were associated with a delayed resumption of sexual intercourse. Women who had greater experience with abortion or the number of living children resumed sexual intercourse earlier than their counterparts.


Assuntos
Coito , Período Pós-Parto , Aleitamento Materno , Criança , China/epidemiologia , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Comportamento Sexual
12.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614060

RESUMO

Cathepsin L protease, which belongs to the papain-like cysteine proteases family, is an important player in many physiological and pathological processes. However, little was known about the role of cathepsin L in ladybird beetles (Coccinella septempuctata Linnaeus) during diapause. Here, we analyzed the characteristics of cathepsin L (CsCatL) in the females of C. septempunctata and its role during the diapause of the ladybeetle. CsCatL was cloned and identified from beetle specimens by rapid amplification of cDNA-ends (RACE). The cDNA sequence of CsCatL was 971 bp in length, including an 843 bp open reading frame encoding a protein of 280 amino acids. It was identified as the cathepsin L group by phylogenetic analysis. Knockdown of CsCatL by RNA interference led to decreased expression levels of fatty acid synthase 2 (fas 2) genes and suppressed lipid accumulation. Furthermore, silencing the CsCatL gene distinctly reduced diapause-related features and the survival of female C. spetempunctata under diapause-inducing conditions. The results suggested that the CsCatL gene was involved in fatty acid biosynthesis and played a crucial role in the survival of adult C. septempunctata during the diapause preparation stage.


Assuntos
Besouros , Diapausa , Animais , Feminino , Catepsina L/genética , Catepsina L/metabolismo , Filogenia , DNA Complementar , Besouros/metabolismo , Diapausa/genética , Lipídeos
13.
Crit Rev Eukaryot Gene Expr ; 31(2): 63-73, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34347980

RESUMO

The purpose of this study was to elucidate the role that the miR-18a-5p/THBD regulatory pathway plays in endometrial cancer (EC), which could provide a theoretical basis for potential therapeutic targets. Differentially expressed genes in EC tissue and normal tissue were determined by bioinformatics analysis. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to compare the expression of miR-18a-5p and THBD mRNA in normal human endometrial cells and human EC cells. CCK-8 assay was used to compare the proliferative ability of EC cells in different treatment groups. Transwell assay was used to detect the migratory and invasive abilities of EC cells in different treatment groups. Dual-luciferase assay was used to verify the targeting relationship between miR-18a-5p and THBD. Western blot assay was used to detect THBD protein expression level. qRT-PCR results showed that miR-18a-5p was significantly upregulated in EC cells, and expression of its target gene, THBD, was significantly downregulated. CCK-8 and transwell assays showed that miR-18a-5p could enhance the proliferative, migratory, and invasive abilities of EC cells, whereas THBD could weaken those abilities. Dual-luciferase assay confirmed that miR-18a-5p could negatively regulate THBD expression. In addition, rescue experiments revealed that the oncogenic effect of miR-18a-5p on EC cells was inhibited by THBD overexpression. We conclude that miR-18a-5p could promote the proliferation, migration, and invasion of EC cells by targeting and downregulating THBD expression, and the miR-18a-5p/THBD regulatory pathway might be a therapeutic target. The results of this study may serve as a theoretical basis for related drug development.


Assuntos
Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias do Endométrio/patologia , MicroRNAs/fisiologia , Invasividade Neoplásica/fisiopatologia , Trombomodulina/metabolismo , Feminino , Inativação Gênica , Humanos , MicroRNAs/metabolismo , Ligação Proteica , Trombomodulina/genética
14.
Biochem Biophys Res Commun ; 566: 197-203, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34144258

RESUMO

Maytansinoids, the chemical derivatives of Maytansine, are commonly used as potent cytotoxic payloads in antibody-drug conjugates (ADC). Structure-activity-relationship studies had identified the C3 ester side chain as a critical element for antitumor activity of maytansinoids. The maytansinoids bearing the methyl group at C3 position with D configuration were about 100 to 400-fold less cytotoxic than their corresponding L-epimers toward various cell lines. The detailed mechanism of how chirality affects the anticancer activity remains elusive. In this study, we determined the high-resolution crystal structure of tubulin in complex with maytansinol, L-DM1-SMe and D-DM1-SMe. And we found the carbonyl oxygen atom of the ester moiety and the tail thiomethyl group at C3 side chain of L-DM1-SMe form strong intramolecular interaction with the hydroxyl at position 9 and the benzene ring, respectively, fixing the bioactive conformation and enhancing the binding affinity. Additionally, ligand-based and structure-based virtually screening methods were used to screen the commercially macrocyclic compounds library, and 15 macrocyclic structures were picketed out as putatively new maytansine-site inhibitors. Our study provides a possible strategy for the rational discovery of next-generation maytansine site inhibitors.


Assuntos
Antineoplásicos/farmacologia , Maitansina/análogos & derivados , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/química , Descoberta de Drogas , Ésteres/química , Ésteres/farmacologia , Humanos , Imunoconjugados/química , Imunoconjugados/farmacologia , Maitansina/química , Maitansina/farmacologia , Modelos Moleculares , Suínos
15.
Biochem Biophys Res Commun ; 565: 29-35, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34090207

RESUMO

Microtubule-targeting agents (MTAs) are the most commonly used anti-cancer drugs. At least fourteen microtubule inhibitors and ten antibody drug conjugates (ADCs) linking MTAs are approved by FDA for clinical use in cancer therapy. In current research, we determined the crystal structure of tubulysin analogue TGL in complex with tubulin at a high resolution (2.65 Å). In addition, we summarized all of the previously published high-resolution crystal structures of ligands in the vinca site to provide structural insights for the rational design of the new vinca-site ligands. Moreover, based on the aligned results of the vinca site ligands, we provided three possible routes for designing new tubulysin analogues, namely macrocyclization between the N-14 side chain and the N-9 side chain, the hybird of tubulysin M and phomopsin A, and growing new aryl group at C-21. These designed structures will inspire the development of new MTAs or payloads in cancer therapy.


Assuntos
Tubulina (Proteína)/química , Cristalografia por Raios X , Humanos , Modelos Moleculares , Conformação Proteica
16.
Cutan Ocul Toxicol ; 40(1): 45-53, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33438439

RESUMO

Objective: The expression of therapeutic proteins in plant oil body bioreactors has attracted much attention. But its safety is not yet clear. This article determines the risk of safety after using the drug. Methods: The oil body-linked oleosin-hEGF microgel emulsion (OBEME) was prepared by mixing the xanthan gum with suitable concentrations in an appropriate proportion. Skin irritation and sensitization reaction were investigated in rats and guinea pigs using OBEME as test article.Results: The OBEME did not produce dermal erythema/eschar or oedema responses. The dermal subacute and subchronic toxicity of OBEME were evaluated in accordance with OECD guidelines. Compared with the control group, the basic physical signs, such as weight, feed, drinking, excretion, and behaviour of experimental animals, were not abnormal. In addition, no abnormality was found in haematological parameters, biochemical indexes, relative organ weight, and histopathological observation of organs, and there was no significant difference compared with normal saline treatment group. Therefore, we conclude that OBEME has no toxic effects and is safe and reliable to be used for topical application.


Assuntos
Portadores de Fármacos/toxicidade , Fator de Crescimento Epidérmico/toxicidade , Proteínas de Plantas/toxicidade , Proteínas Recombinantes de Fusão/toxicidade , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Reatores Biológicos/efeitos adversos , Carthamus tinctorius/genética , Dermatite de Contato/diagnóstico , Dermatite de Contato/etiologia , Dermatite de Contato/patologia , Portadores de Fármacos/química , Avaliação Pré-Clínica de Medicamentos , Emulsões , Fator de Crescimento Epidérmico/administração & dosagem , Fator de Crescimento Epidérmico/genética , Eritema/induzido quimicamente , Eritema/diagnóstico , Cobaias , Humanos , Gotículas Lipídicas/química , Masculino , Microgéis , Proteínas de Plantas/administração & dosagem , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ratos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Pele/imunologia , Pele/lesões , Pele/patologia , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Subaguda/métodos , Testes de Toxicidade Subcrônica/métodos , Cicatrização/efeitos dos fármacos
17.
Anal Chem ; 92(1): 1138-1146, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31820637

RESUMO

With currently available molecular imaging techniques, hepatocellular carcinoma (HCC), a liver cancer with high mortality rates and poor treatment responses, is mostly diagnosed at its late stage. This is largely due to the lack of highly sensitive contrast agents with high liver specificity. Herein, we report a novel bimodal contrast agent molecule CNCI-1 for the effective detection of HCC at its early stage both in vitro and in vivo. The agent has high liver specificity with effective X-ray computed tomography (CT)/near-infrared (NIR) imaging functions. It has been successfully applied to in vivo NIR imaging with high sensitivity and high selectivity to the HCC region of the HepG2 tumor-xenografted mice model and LM3 orthotopic hepatoma mice model. Moreover, the agent was found to be noninvasive and hepatocarcinoma cells preferential. Furthermore, it also enhanced the tumor imaging by revealing the blood vessels nearby for the CT image acquisition in the VX2 orthotopic hepatoma rabbit model. Our design strategy provides a new avenue to develop the medical relevant bimodal contrast agents for diagnosis of HCC at its early stage.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste/química , Neoplasias Hepáticas/diagnóstico por imagem , Acetanilidas/síntese química , Acetanilidas/química , Acetanilidas/toxicidade , Animais , Carcinoma Hepatocelular/patologia , Meios de Contraste/síntese química , Meios de Contraste/toxicidade , Células Hep G2 , Humanos , Indóis/síntese química , Indóis/química , Indóis/toxicidade , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Coelhos , Tomografia Computadorizada por Raios X
18.
Bioconjug Chem ; 31(1): 2-15, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31769660

RESUMO

Alzheimer's disease (AD) is an irreversible neurodegenerative disorder. Currently, there are no available treatments that can effectively stop or reverse the progression of the disease, and existing therapeutics can only alleviate the symptoms. Thus, it remains urgent to develop effective early-stage AD diagnostic methods. In recent years, the search for near-infrared fluorescent (NIRF) probes of AD hallmarks has become a promising research field. In this Review, we will focus on small-molecule NIRF probes used to detect ß-amyloid, tau proteins, and reactive oxygen species in vivo during the past 4 years. We believe that some new directions we raise herein will benefit the future development of NIRF probes in the field of AD research.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Corantes Fluorescentes/química , Espécies Reativas de Oxigênio/análise , Proteínas tau/análise , Doença de Alzheimer/diagnóstico por imagem , Animais , Humanos , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Espectrometria de Fluorescência/métodos
19.
Clin Sci (Lond) ; 134(2): 261-271, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31922199

RESUMO

Acute myeloid leukemia (AML) is a malignant disorder of hemopoietic stem cells. AML can escape immunosurveillance of natural killer (NK) by gene mutation, fusions and epigenetic modification. The mechanism of AML immune evasion is not clearly understood. Here we show that CD48 high expression is a favorable prognosis factor that is down-regulated in AML patients, which can help AML evade from NK cell recognition and killing. Furthermore, we demonstrate that CD48 expression is regulated by methylation and that a hypomethylating agent can increase the CD48 expression, which increases the NK cells killing in vitro. Finally, we show that CD48 high expression can reverse the AML immune evasion and activate NK cells function in vivo. The present study suggests that a combination the hypomethylating agent and NK cell infusion could be a new strategy to cure AML.


Assuntos
Antígeno CD48/imunologia , Epigênese Genética/imunologia , Inativação Gênica/imunologia , Leucemia Mieloide/imunologia , Evasão Tumoral/imunologia , Doença Aguda , Animais , Antimetabólitos Antineoplásicos/farmacologia , Antígeno CD48/genética , Linhagem Celular Tumoral , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Metilação de DNA/imunologia , Decitabina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Estimativa de Kaplan-Meier , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Masculino , Camundongos Endogâmicos BALB C , Evasão Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Bioorg Med Chem ; 28(13): 115559, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32546301

RESUMO

Amyloid-ß oligomers (AßOs) enrichment in brain is highly related to Alzheimer's pathogenesis, but tracing them in the brain by imaging technique is still a great challenge due to their heterogeneity and metastability. Herein, a new near-infrared (NIR) fluorescent probe, namely, PTO-41, was designed and synthesized to specifically target AßOs. PTO-41 possesses excellent functional properties including optimal fluorescent properties (emission maxima at 680 nm upon interacting with AßOs), high affinity (Kd = 349 nM), low cell toxicity, desirable lipophilicity (log P = 2.24), and fast wash out from the brain (brain2 min/brain60 min = 5.0). Furthermore, PTO-41 exhibits a high sensitivity toward AßOs in vitro phantom imaging experiments. More importantly, PTO-41 shows great capacity to differentiate between 4-month-old APP/PS1 model mice from age-matched control mice using in vivo imaging. In summary, PTO-41 almost meets all the requirements as a versatile NIR fluorescent probe for the detection of AßOs both in vitro and in vivo.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/análise , Ácidos Borínicos/síntese química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Ácidos Borínicos/metabolismo , Encéfalo/metabolismo , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Humanos , Técnicas In Vitro , Raios Infravermelhos , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Imagem Óptica
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