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1.
J Nanobiotechnology ; 22(1): 105, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468249

RESUMO

Chemotherapy is an important therapeutic approach for malignant tumors for it triggers apoptosis of cancer cells. However, chemotherapy also induces senescence of stromal cells in the tumor microenvironment to promote tumor progression. Strategies aimed at killing tumor cells while simultaneously eliminating senescent stromal cells represent an effective approach to cancer treatment. Here, we developed an engineered Src-siRNA delivery system based on small extracellular vesicles (sEVs) to simultaneously eliminate senescent stromal cells and tumor cells for cancer therapy. The DSPE-PEG-modified urokinase plasminogen activator (uPA) peptide was anchored to the membranes of induced mesenchymal stem cell-derived sEVs (uPA-sEVs), and Src siRNA was loaded into the uPA-sEVs by electroporation (uPA-sEVs-siSrc). The engineered uPA-sEVs-siSrc retained the basic sEVs properties and protected against siSrc degradation. uPA peptide modification enhanced the sEVs with the ability to simultaneously target doxorubicin-induced senescent stromal cells and tumor cells. Src silencing by uPA-sEVs-siSrc induced apoptosis of both senescent stromal cells and tumor cells. The uPA-sEVs-siSrc displayed preferential tumor accumulation and effectively inhibited tumor growth in a tumor xenograft model. Furthermore, uPA-sEVs-siSrc in combination with doxorubicin significantly reduced the senescence burden and enhanced the therapeutic efficacy of chemotherapy. Taken together, uPA-sEVs-siSrc may serve as a promising therapy to kill two birds with one stone, not only killing tumor cells to achieve remarkable antitumor effect, but also eliminating senescent cells to enhance the efficacy of chemotherapeutic agent in tumor regression.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Neoplasias/tratamento farmacológico , RNA Interferente Pequeno , Células Estromais/metabolismo , Vesículas Extracelulares/metabolismo , Doxorrubicina/farmacologia , Peptídeos , Microambiente Tumoral
2.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401527

RESUMO

Following invasion, insects can become adapted to conditions experienced in their invasive range, but there are few studies on the speed of adaptation and its genomic basis. Here, we examine a small insect pest, Thrips palmi, following its contemporary range expansion across a sharp climate gradient from the subtropics to temperate areas. We first found a geographically associated population genetic structure and inferred a stepping-stone dispersal pattern in this pest from the open fields of southern China to greenhouse environments of northern regions, with limited gene flow after colonization. In common garden experiments, both the field and greenhouse groups exhibited clinal patterns in thermal tolerance as measured by critical thermal maximum (CTmax) closely linked with latitude and temperature variables. A selection experiment reinforced the evolutionary potential of CTmax with an estimated h2 of 6.8% for the trait. We identified 3 inversions in the genome that were closely associated with CTmax, accounting for 49.9%, 19.6%, and 8.6% of the variance in CTmax among populations. Other genomic variations in CTmax outside the inversion region were specific to certain populations but functionally conserved. These findings highlight rapid adaptation to CTmax in both open field and greenhouse populations and reiterate the importance of inversions behaving as large-effect alleles in climate adaptation.


Assuntos
Adaptação Fisiológica , Inversão Cromossômica , Animais , Adaptação Fisiológica/genética , Clima , Temperatura , Insetos
3.
Biotechnol Biofuels Bioprod ; 16(1): 161, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891680

RESUMO

BACKGROUND: The well-known industrial fungus Trichoderma reesei has an excellent capability of secreting a large amount of cellulases and xylanases. The induced expression of cellulase and xylanase genes is tightly controlled at the transcriptional level. However, compared to the intensive studies on the intricate regulatory mechanism of cellulase genes, efforts to understand how xylanase genes are regulated are relatively limited, which impedes the further improvement of xylanase production by T. reesei via rational strain engineering. RESULTS: To identify transcription factors involved in regulating xylanase gene expression in T. reesei, yeast one-hybrid screen was performed based on the promoters of two major extracellular xylanase genes xyn1 and xyn2. A putative transcription factor named XTR1 showing significant binding capability to the xyn1 promoter but not that of xyn2, was successfully isolated. Deletion of xtr1 significantly increased the transcriptional level of xyn1, but only exerted a minor promoting effect on that of xyn2. The xylanase activity was increased by ~ 50% with XTR1 elimination but the cellulase activity was hardly affected. Subcellular localization analysis of XTR1 fused to a green fluorescence protein demonstrated that XTR1 is a nuclear protein. Further analyses revealed the precise binding site of XTR1 and nucleotides critical for the binding within the xyn1 promoter. Moreover, competitive EMSAs indicated that XTR1 competes with the essential transactivator XYR1 for binding to the xyn1 promoter. CONCLUSIONS: XTR1 represents a new transcriptional repressor specific for controlling xylanase gene expression. Isolation and functional characterization of this new factor not only contribute to further understanding the stringent regulatory network of xylanase genes, but also provide important clues for boosting xylanase biosynthesis in T. reesei.

4.
Pest Manag Sci ; 79(11): 4282-4289, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37345405

RESUMO

BACKGROUND: Several agricultural fungicides are known to affect insect pests directly and these effects may be transgenerational and mediated through impacts on endosymbionts, providing opportunities for pest control. The cotton aphid Aphis gossypii is a polyphagous pest that can cause large crop yield losses. Here, we tested the effects of three fungicides, pyraclostrobin, trifloxystrobin and chlorothalonil, on the fitness and Buchnera endosymbiont of A. gossypii. RESULTS: The formulations of trifloxystrobin and pyraclostrobin, and the active ingredient of pyraclostrobin produced dose-dependent mortality in A. gossypii, whereas there was no dose-dependent mortality for chlorothalonil. The formulations of trifloxystrobin and pyraclostrobin significantly reduced the lifespan and fecundity of A. gossypii, and increased the density of Buchnera in the parental generation but not the (unexposed) F1 . When the active ingredient of pyraclostrobin was tested, the lifespan of the F0 generation was also reduced, but the density of Buchnera was not, indicating that non-insecticidal chemicals in the fungicide formulation may affect the density of the endosymbiont of A. gossypii. There was no transgenerational effect of the active ingredient of pyraclostrobin on the lifespan and Buchnera of (unexposed) F1 . CONCLUSIONS: Our results suggest that formulations of two strobilurin fungicides have immediate impacts on the fitness of A. gossypii, and chemicals in the formulation impact the density of the primary Buchnera endosymbiont. Our study highlights the potential effects of non-insecticidal chemicals of fungicides on aphid pests and their primary endosymbionts but direct connections between fitness and Buchnera densities remain unclear. © 2023 Society of Chemical Industry.

5.
Pest Manag Sci ; 79(9): 3218-3226, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37042232

RESUMO

BACKGROUND: Field control of pest thrips mainly relies on insecticides, but the toxicity of insecticides can vary among thrips species and populations. In this study, we examined the susceptibility of multiple field populations of two thrips pests, Frankliniella occidentalis, and Thrips palmi, that often co-occur on vegetables, to nine insecticides belonging to seven subgroups. RESULTS: The highest level of variation in susceptibility among F. occidentalis populations was for spinetoram (73.92 fold difference between most resistant and most susceptible population), followed by three neonicotinoids (8.06-15.99 fold), while among T. palmi populations, it was also for spinetoram (257.19 fold), followed by emamectin benzoate, sulfoxaflor, and acetamiprid (23.64-45.50 fold). These findings suggest evolved resistance to these insecticides in some populations of the two thrips. One population of F. occidentalis had a particularly high level of resistance overall, being the most resistant for five of the nine insecticides tested. Likewise, a population of T. palmi had high resistance to all nine insecticides, again suggesting the evolution of resistance to multiple chemicals. For F. occidentalis, the LC95 values of most populations were higher than the field-recommended dosage for all insecticides except chlorfenapyr and emamectin benzoate. For several T. palmi populations, the LC95 values also tended to be higher than recommended dosages, except in the case of emamectin benzoate and spinetoram. CONCLUSIONS: Our study found interspecific and intraspecific variations in the susceptibility of two thrips to nine insecticides and multiple resistance in some populations, highlighting the need for ongoing monitoring and resistance management. © 2023 Society of Chemical Industry.


Assuntos
Inseticidas , Tisanópteros , Animais , Inseticidas/farmacologia , Macrolídeos
6.
Ann Transl Med ; 10(14): 762, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35965798

RESUMO

Background: Polycystic ovary syndrome (PCOS) is the most common reproductive endocrine disease in women of childbearing age, and insulin resistance is an important etiological mechanism in PCOS. This study revealed the microRNA (miRNA) expression profile of PCOS with insulin resistance and explored the potential biological functions of differentially expressed miRNA. Methods: A total of 76 patients with PCOS and 30 normal healthy women were recruited in the gynecological clinic of the Second Hospital of Tianjin Medical University. We divided the patients with PCOS into a group with insulin resistance (n=46) and a group without insulin resistance (n=30). Peripheral venous serum samples from each group were used for deep sequencing to identify differentially expressed miRNAs. Hierarchical clustering heat maps were used to show differences in miRNA expression. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and target gene network databases were used to explore the potential target genes of differentially expressed miRNAs and to analyze their specific biological functions. Results: A case-control analysis found that the levels of body mass index (BMI), prolactin (PRL), total testosterone (T), fasting blood glucose (FBG), and fasting insulin (INS) in patients with PCOS were higher than those in healthy controls. High BMI, high blood sugar, and hyperinsulinemia were more significant in the PCOS with insulin resistance group than without insulin resistance group. Among the patients with PCOS, miR-122-5p was found to have more significant differences in the PCOS with insulin resistance group. GO and KEGG pathway analysis showed that the identified miRNAs were involved in the regulation of different biological processes, such as signal transduction, negative regulation of GTPase activity, chloride channel complex. The predicted target genes were related to the citrate cycle (TCA cycle) and the biosynthesis of mucin-type O-glycans. Conclusions: Our research demonstrated the use of miRNAs as new biomarkers for the diagnosis, treatment and presented a new strategy to lessen the symptoms of PCOS with insulin resistance.

7.
Front Microbiol ; 13: 810066, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154055

RESUMO

The filamentous fungus Trichoderma reesei secretes large quantities of cellulases and hemicellulases that have found wide applications in industry. Compared with extensive studies on the mechanism controlling cellulase gene expression, less is known about the regulatory mechanism behind xylanase gene expression. Herein, several putative sugar transporter encoding genes that showed significant upregulation on xylan were identified in T. reesei. Deletion of one such gene, gat1, resulted in increased xylanase production but hardly affected cellulase induction. Further analyses demonstrated that deletion of gat1 markedly increased XYNI production at the transcriptional level and only exerted a minor effect on XYNII synthesis. In contrast, overexpressing gat1 caused a continuous decrease in xyn1 expression. Deletion of gat1 also affected the expression of xyn1 and pectinase genes when T. reesei was cultivated with galacturonic acid as the sole carbon source. Transcriptome analyses of Δgat1 and its parental strain identified 255 differentially expressed genes that are enriched in categories of glycoside hydrolases, lipid metabolism, transporters, and transcriptional factors. The results thus implicate a repressive role of the sugar transporter GAT1 in xyn1 expression and reveal that distinct regulatory mechanisms may exist in controlling the expression of different xylanase genes in T. reesei.

8.
Pharmaceuticals (Basel) ; 15(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35215270

RESUMO

Glioma is among the deadliest types of brain cancer, for which there currently is no effective treatment. Chemotherapy is mainstay in the treatment of glioma. However, drug tolerance, non-targeting, and poor blood-brain barrier penetrance severely inhibits the efficacy of chemotherapeutics. An improved treatment method is thus urgently needed. Herein, a multifunctional biomimetic nanoplatform was developed by encapsulating graphene quantum dots (GQDs) and doxorubicin (DOX) inside a homotypic cancer cell membrane (CCM) for targeted chemo-photothermal therapy of glioma. The GQDs with stable fluorescence and a superior light-to-heat conversion property were synthesized as photothermal therapeutic agents and co-encapsulated with DOX in CCM. The as-prepared nanoplatform exhibited a high DOX loading efficiency. The cell membrane coating protected drugs from leakage. Upon an external laser stimuli, the membrane could be destroyed, resulting in rapid DOX release. By taking advantage of the homologous targeting of the cancer cell membrane, the GQDs/DOX@CCM were found to actively target tumor cells, resulting in significantly enhanced cellular uptake. Moreover, a superior suppression efficiency of GQDs/DOX@CCM to cancer cells through chemo-photothermal treatment was also observed. The results suggest that this biomimetic nanoplatform holds potential for efficient targeting of drug delivery and synergistic chemo-photothermal therapy of glioma.

9.
J Agric Food Chem ; 70(1): 211-222, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34935374

RESUMO

The industrial fungus Trichoderma reesei has an outstanding capability of secreting an enzyme cocktail comprising multiple plant biomass-degrading enzymes. Herein, the overexpression of XYR1, the master transactivator controlling (hemi)cellulase gene expression, was performed in T. reesei lacking four main cellulase-encoding genes. The resultant strain Δ4celOExyr1 was able to produce a dramatically different profile of secretory proteins on soluble glucose or lactose compared with that of the wild-type T. reesei. The Δ4celOExyr1 secretome included cellulases EGIII and BGLI as well as several hemicellulases and nonhydrolytic cellulose degradation-associated proteins that are not preferentially induced in the wild-type T. reesei strain. Δ4celOExyr1 produced a significant amount of α-arabinofuranosidase I on lactose, and the crude enzyme cocktail of Δ4celOExyr1 not only released a considerable quantity of glucose but also exhibited remarkable performance in the hydrolytic release of xylose, arabinose, and mannose from un-pretreated corn fiber. These results showed that the engineered T. reesei strain holds great potential for improving the saccharification efficiency of the hemicellulosic constituents within corn fiber.


Assuntos
Celulase , Celulases , Trichoderma , Celulase/metabolismo , Celulases/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Hypocreales , Secretoma , Trichoderma/genética , Trichoderma/metabolismo , Zea mays/genética , Zea mays/metabolismo
10.
Int J Nanomedicine ; 16: 2123-2136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33731994

RESUMO

PURPOSE: Nanomaterial-based drug-delivery systems allowing for effective targeted delivery of smallmolecule chemodrugs to tumors have revolutionized cancer therapy. Recently, as novel nanomaterials with outstanding physicochemical properties, boron nitride nanospheres (BNs) have emerged as a promising candidate for drug delivery. However, poor dispersity and lack of tumor targeting severely limit further applications. In this study, cancer cell-membrane biomimetic BNs were designed for targeted anticancer drug delivery. METHODS: Cell membrane extracted from HeLa cells (HM) was used to encapsulate BNs by physical extrusion. Doxorubicin (Dox) was loaded onto HM-BNs as a model drug. RESULTS: The cell-membrane coating endowed the BNs with excellent dispersibility and cytocompatibility. The drug-release profile showed that the Dox@HM-BNs responded to acid pH, resulting in rapid Dox release. Enhanced cellular uptake of Dox@HM-BNs by HeLa cells was revealed because of the homologous targeting of cancer-cell membranes. CCK8 and live/dead assays showed that Dox@HM-BNs had stronger cytotoxicity against HeLa cells, due to self-selective cellular uptake. Finally, antitumor investigation using the HeLa tumor model demonstrated that Dox@HM-BNs possessed much more efficient tumor inhibition than free Dox or Dox@BNs. CONCLUSION: These findings indicate that the newly developed HM-BNs are promising as an efficient tumor-selective drug-delivery vehicle for tumor therapy.


Assuntos
Materiais Biomiméticos/química , Compostos de Boro/química , Membrana Celular/patologia , Terapia de Alvo Molecular , Nanosferas/química , Neoplasias/patologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Nanosferas/ultraestrutura , Neoplasias/tratamento farmacológico , Espectrometria por Raios X , Distribuição Tecidual/efeitos dos fármacos
11.
Medicine (Baltimore) ; 99(10): e19366, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32150082

RESUMO

BACKGROUND: Perimenopause is a period that every woman must go through, most people are more or less affected by perimenopausal symptoms, it to affect women's health, work, life, and economy. As acupuncture treatment is more and more increasing in perimenopausal symptoms, there have also been many clinical trials about it. But the results of the trials are inconsistent. Therefore, we will conduct a systematic review and meta-analysis of the safety and efficacy of perimenopausal symptoms treated with acupuncture. METHODS: The protocol followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. RCT study on different acupuncture interventions for perimenopausal symptoms will be searched in 8 databases (PubMed, EMBASE, the Cochrane Library, the web of science, CBM, CNKI, WAN FANG, and VIP). Besides, the search will also be performed on the clinical trial research platform if necessary. The primary outcome that will be extracted: the Flushes per 24 hours, the Frequency of hot flashes, the severity of hot flashes, the menopause-related symptom score, the treatment efficacy, the adverse event. Endnote software X8 will be used for study selection, STATA 13.0 and Review Manager software 5.3 will be used for analysis and synthesis. These studies selection, data extraction, and risk of bias assessment will be conducted by 2 independent reviewers. RESULTS: This study will provide the results: 1. the primary and secondary outcome indicators of different acupuncture intervention measures (traditional hand acupuncture, moxibustion, ear acupuncture, laser, acupressure points) for perimenopausal symptoms. 2. The effects of different control groups (medicine control, routine care, waiting, and sham acupuncture control) on the analysis results will be reported, especially the effects of different sham acupuncture control (invasive/noninvasive) on the analysis results. CONCLUSION: This systematic review and meta-analysis study hopes to provide useful evidence for better use of different types of acupuncture in treat perimenopausal symptoms and better design of control groups in related clinical trials. In addition, the research conclusion will be published in peer journals.OSF REGISTRATION NUMBER DOI 10.17605/OSF.IO/VZCKU Ethics and dissemination This conclusion of the study will be published in peer journals. The ethical approval is not required because there is no direct involvement of human.


Assuntos
Terapia por Acupuntura/normas , Perimenopausa/psicologia , Terapia por Acupuntura/métodos , Idoso , Protocolos Clínicos , Grupos Controle , Feminino , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Revisões Sistemáticas como Assunto , Resultado do Tratamento
12.
Colloids Surf B Biointerfaces ; 190: 110964, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32179413

RESUMO

Boron nitride nanospheres (BNNS) have attracted increasing attention in many fields due to their unique physicochemical properties. Biomedical application of BNNS has also been explored recently. However, limited by the hydrophobicity and poor dispersity of BNNS, their biocompatible performance especially the in vivo biosafety has rarely been reported and is still unclear now. In this work, BNNS were firstly camouflaged with red blood cell membrane by physical extrusion (CM-BNNS). CM-BNNS were then incubated with cells as well as intravenously injected into the mice to uncover their potential in vitro and in vivo toxicity. Results were promising as CM-BNNS exhibited better dispersion and stability compared with pristine BNNS. In vitro data demonstrated the relatively enhanced biosafety of CM-BNNS. The red blood cell membrane coating endowed BNNS with markedly prolonged blood circulation and decreased accumulation in the lung. In addition, CM-BNNS showed no adverse effects on all the evaluated hematic parameters and tissues of treated mice at a dose of 10 mg/kg. Taken together, our work demonstrated the optimal biocompatibility of CM-BNNS and pave the way for their future biomedical applications.


Assuntos
Materiais Biocompatíveis/farmacologia , Compostos de Boro/farmacologia , Membrana Celular/química , Eritrócitos/química , Nanosferas/química , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Compostos de Boro/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Feminino , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos , Tamanho da Partícula , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
13.
Neurol Res ; 33(10): 1109-14, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22196765

RESUMO

OBJECTIVE: To study the effect of hippocampal bone marrow stromal cells (GFP-BMSCs) transplantation on spatial memory and DeltaNp73 expression in APP/PS1 transgenic mice. METHODS: Twelve APP/PS1 transgenic mice randomly received either 10 µl GFP-BMSCs suspension in medium (GFP-BMSCs transplantation group) or 10 µl complete medium (sham-operated group). Learning and memory function of mice in both groups were observed and tested in Morris water maze experiment at 2 weeks after surgery. Senile plaques and DeltaNp73 protein in hippocampuses were determined by immunohistochemistry and western blot at 3 weeks after surgery, respectively. RESULTS: APP/PS1 mice treated with BMSCs performed significantly better on the water maze test than those in sham-operated group (P<0·05). Immunohistochemistry showed that GFP-BMSCs distributed uniformly and the number of Alzheimer's senile plaques reduced after transplantation. Western blot showed that quantified DeltaNp73 protein expression was significantly higher in BMSCs transplantation group when compared with sham-operated group (P<0·01). CONCLUSIONS: Our results suggest that BMSCs transplatation could retard Alzheimer's disease (AD) like pathology and upregulate DeltaNp73 expression in hippocampuses of APP/PS1 transgenic mice. GFP-BMSCs transplantation will be a potential treatment for AD.


Assuntos
Transplante de Medula Óssea/métodos , Hipocampo/metabolismo , Hipocampo/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Proteínas Nucleares/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/cirurgia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Presenilina-1/genética , Presenilina-1/metabolismo , Cultura Primária de Células , Resultado do Tratamento
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