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1.
Front Cell Infect Microbiol ; 14: 1372779, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596652

RESUMO

Aflatoxins (AFs) are produced by fungi such as Aspergillus flavus and A. parasiticus and are one of the most toxic mycotoxins found in agricultural products and food. Aflatoxin contamination, which requires the control of A. flavus, remains problematic because of the lack of effective strategies and the exploration of new compounds that can inhibit A. flavus growth and mycotoxin production is urgently required to alleviate potential deleterious effects. Acetohydroxy acid synthase (AHAS) and dihydroxy acid dehydratase are important enzymes in the biosynthetic pathways of branched-chain amino acids (BCAAs), including isoleucine, leucine, and valine. Enzymes involved in BCAA biosynthesis are present in bacteria, plants, and fungi, but not in mammals, and are therefore, attractive targets for antimicrobial and herbicide development. In this study, we characterized AflaILVB/G/I and AflaILVD, which encode the catalytic and regulatory subunits of AHAS and dihydroxy acid dehydratase, from the pathogenic fungus Aspergillus flavus. The AflaILVB/G/I and AflaILVD deletion mutant grew slower and produced smaller colonies than the wild-type strain when grown on glucose minimal medium, potato dextrose agar, and yeast extract medium for three days at 28°C, and disruption of AflaILVB/G/I caused a significant reduction in conidia production when grown on all kinds of media. Cellular stress assays determined that all strains were sensitive to H2O2. Importantly, the pathogenicity and aflatoxin production were affected when AflaILVB/G/I and AflaILVD were knocked out, particularly AflaILVB/G/I. A series of genes that encoded enzymes involved in aflatoxin synthesis were downregulated, meaning that the knockout of AflaILVB/G/I influenced aflatoxin synthesis in A. flavus strain WT. Collectively, our results demonstrate the potential value of antifungals targeting AflaILVB/G/I in A. flavus.


Assuntos
Aflatoxinas , Aspergillus flavus , Animais , Aspergillus flavus/genética , Virulência , Peróxido de Hidrogênio/metabolismo , Hidroliases , Mamíferos
2.
J Fungi (Basel) ; 9(12)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38132793

RESUMO

Aspergillus flavus is an important fungus that produces aflatoxins, among which aflatoxin B1 (AFB1) is the most toxic and contaminates food and poses a high risk to human health. AFB1 interacts with another mycotoxin sterigmatocystin (STC), which is also a precursor of AFB1. Herein, we determined the effect of STC on AFB1 by evaluating A. flavus transcriptomic and proteomic profiles in the presence or absence of STC by RNA-seq and isobaric tagging, respectively. Overall, 3377 differentially expressed genes were identified by RNA-seq. These genes were mainly associated with the cellular component organisation and biosynthesis, the synthesis of valine, leucine, and isoleucine, and the synthesis of aflatoxin. Clustered genes responsible for AFB1 biosynthesis exhibited varying degrees of downregulation, and norB expression was completely suppressed in the experimental group. During proteomic analysis, 331 genes were differentially expressed in response to STC. These differentially expressed proteins were associated with cell parts and catalytic and antioxidant activities. Differentially expressed proteins predominantly participated in metabolic pathways associated with aflatoxin biosynthesis, glycolysis/gluconeogenesis, glutathione metabolism, and carbon metabolism. Notably, the upregulated and downregulated enzymes in carbohydrate and glutathione metabolisms may serve as potential gateways for inhibiting aflatoxin biosynthesis. Moreover, twelve proteins including seven downregulated ones involved in aflatoxin biosynthesis were identified; among them, AflG was the most downregulated, suggesting that it may be the key enzyme responsible for inhibiting aflatoxin synthesis. These findings provide novel insights into A. flavus control and the mechanisms regulating mycotoxin production.

3.
J Agric Food Chem ; 71(47): 18443-18453, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37975831

RESUMO

2-Acetyl-1-pyrroline (2-AP) is a fragrance compound and flavor in fragrant rice whose precursors are generally glutamate (Glu) and proline (Pro). Our previous study revealed that exogenous Glu enhanced the arsenic (As) tolerance in fragrant rice by improving the ascorbic acid-glutathione cycle and the Pro content in roots. However, less is known about how Glu is involved in 2-AP biosynthesis in fragrant rice under As stress. Herein, a hydroponic experiment of L-Glu seed priming with 0, 100, and 500 µM l-glutamic acid solutions was conducted with two fragrant rice varieties. After that, the 10-day-old seedlings were cultured under 0 and 100 µM arsenite stress for 10 d. Results showed that the 2-AP and Pro contents were increased by 18-30% and 21-78% under As100 µM-Glu100 µM treatment in comparison to the control As100 µM to Glu0 µM, while the activities of pyrroline-5-carboxylate synthetase (P5CS) and proline dehydrogenase (ProDH) were increased by 19-46% and 3-19%, respectively. Furthermore, the 2-AP, Pro contents, and P5CS activity were correlated positively. Correspondingly, a significant abundance of differential expressed metabolites (18) and differential expressed genes (26) was observed in amino acid metabolism and glutathione metabolism pathways. In addition, several essential genes were verified and grouped into the pathways of glutathione metabolism, proline, and arginine metabolism with antioxidant defense system to comodulate 2-AP biosynthesis and stress detoxification. Therefore, the Glu seed priming treatment had a positive impact on the 2-AP biosynthesis of fragrant rice under 100 µM arsenite toxicity.


Assuntos
Arsenitos , Oryza , Ácido Glutâmico/metabolismo , Oryza/química , Plântula/genética , Plântula/metabolismo , Odorantes , Arsenitos/metabolismo , Sementes/metabolismo , Prolina/metabolismo , Glutationa/metabolismo
4.
Nat Commun ; 14(1): 6610, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857647

RESUMO

The recent success of mRNA therapeutics against pathogenic infections has increased interest in their use for other human diseases including cancer. However, the precise delivery of the genetic cargo to cells and tissues of interest remains challenging. Here, we show an adaptive strategy that enables the docking of different targeting ligands onto the surface of mRNA-loaded small extracellular vesicles (sEVs). This is achieved by using a microfluidic electroporation approach in which a combination of nano- and milli-second pulses produces large amounts of IFN-γ mRNA-loaded sEVs with CD64 overexpressed on their surface. The CD64 molecule serves as an adaptor to dock targeting ligands, such as anti-CD71 and anti-programmed cell death-ligand 1 (PD-L1) antibodies. The resulting immunogenic sEVs (imsEV) preferentially target glioblastoma cells and generate potent antitumour activities in vivo, including against tumours intrinsically resistant to immunotherapy. Together, these results provide an adaptive approach to engineering mRNA-loaded sEVs with targeting functionality and pave the way for their adoption in cancer immunotherapy applications.


Assuntos
Vesículas Extracelulares , Glioblastoma , Humanos , RNA Mensageiro/genética , Imunoterapia/métodos , Vesículas Extracelulares/genética , Eletroporação
5.
J Hazard Mater ; 455: 131640, 2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37201278

RESUMO

Chlorinated paraffins (CPs) are emerging environmental pollutants. Although metabolism has been shown to affect the differential accumulation of short-chain (SCCPs), medium-chain (MCCPs) and long-chain (LCCPs) CPs in birds, CP metabolites have rarely been reported and the extent to which they are formed is still unclear. In this study, single and mixed CP standards were incubated with chicken liver microsomes in vitro to study the generation of CP metabolites. Putative aldehyde/ketone and carboxylic acid metabolites identified by mass spectroscopy data were shown to be false positive results. Phase I metabolism of CPs first formed monohydroxylated ([M-Cl+OH]) and then dihydroxylated ([M-2Cl+2OH]) products. The yields of monohydroxylated metabolites of CPs decreased with increasing carbon chain length and chlorine content at the initial stage of reaction. Notably, the yield of monohydroxylated metabolites of SCCPs with 51.5% Cl content reached 21%, and that of 1,2,5,6,9,10-hexachlorodecane (C10H16Cl6) was as high as 71%. Thus, monohydroxy metabolites of CPs in birds should not be ignored, especially those of SCCPs. This study provides important data that could support improvements to the ecological/health risk assessment of CPs.


Assuntos
Hidrocarbonetos Clorados , Animais , Hidrocarbonetos Clorados/análise , Microssomos Hepáticos , Parafina/química , Galinhas , Monitoramento Ambiental/métodos , China
6.
Nat Biomed Eng ; 7(7): 887-900, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36635419

RESUMO

The success of messenger RNA therapeutics largely depends on the availability of delivery systems that enable the safe, effective and stable translation of genetic material into functional proteins. Here we show that extracellular vesicles (EVs) produced via cellular nanoporation from human dermal fibroblasts, and encapsulating mRNA encoding for extracellular-matrix α1 type-I collagen (COL1A1) induced the formation of collagen-protein grafts and reduced wrinkle formation in the collagen-depleted dermal tissue of mice with photoaged skin. We also show that the intradermal delivery of the mRNA-loaded EVs via a microneedle array led to the prolonged and more uniform synthesis and replacement of collagen in the dermis of the animals. The intradermal delivery of EV-based COL1A1 mRNA may make for an effective protein-replacement therapy for the treatment of photoaged skin.


Assuntos
Derme , Vesículas Extracelulares , Humanos , Camundongos , Animais , Derme/metabolismo , RNA Mensageiro/metabolismo , Colágeno/metabolismo , Pele/metabolismo , Vesículas Extracelulares/metabolismo
7.
Toxics ; 10(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36355971

RESUMO

As one of the most prevalent estrogenic mycotoxins in cereals and animal feed, zearalenone (ZEN) can cause serious reproductive disorders. ZEN control in food and feed commodities has been an imperative area of research. In this study, 87 lactic acid bacteria (LAB) were isolated from pickles and their ZEN (5 mg/L) removal abilities ranged from 0% to 68.4%. Then, five strains with potent ZEN removal ability (>50%) were identified: Lactobacillus plantarum 22, L. plantarum 37, L. plantarum 47, L. paracasei 85, and L. buchneri 93. Under optimization conditions (48 h, pH 4.0, 37 °C, and 5 mg/L), the highest ZEN removal abilities of L. paracasei 85 and L. buchneri 93 reached 77.7% and 72.8%, respectively. Moreover, the two lactic acid bacteria decreased the toxicity of ZEN, because the levels of ß-zearalenol (ß-ZOL) transformed from ZEN were more than two-fold higher than α-zearalenol (α-ZOL). Additionally, cell free supernatant and pellet biotransformation of ZEN to α-ZOL and ß-ZOL in LAB were detected for the first time. Furthermore, chemical and enzymatical treatments combined with Fourier-transform infrared spectroscopy analysis indicated that exopolysaccharides, proteins, and lipids on the cell wall could bond to ZEN through hydrophobic interactions. Scanning electron microscopy indicated that cell structure damage occurred during the ZEN clearance to L. buchneri 93, but it did not with L. paracasei 85. In addition, various organic acids, alcohols, and esters of the two LAB participated in ZEN removal. Hence, L. paracasei 85 and L. buchneri 93 can be considered as potential detoxification agents for ZEN removal for food and feedstuff.

8.
Asian J Pharm Sci ; 17(5): 630-640, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36382306

RESUMO

Liver fibrosis is the deposition of extracellular matrix (ECM) in the liver caused by persistent chronic injury, which can lead to more serious diseases such as cirrhosis or cancer. Blocking the effect of transforming growth factor ß1 (TGF-ß1), one of the most important cytokines in liver fibrosis, may be one of the effective ways to inhibit liver fibrosis. As a kind of natural nano-scale vesicles, small extracellular vesicles (sEvs) have displayed excellent delivery vehicle properties. Herein, we prepared hepatic stellate cell (HSC)-derived sEvs loading left-right determination factor 1 (lefty1) mRNA (sEvLs) and we wanted to verify whether they can inhibit fibrosis by blocking the TGF-ß1 signaling pathway. The results showed that sEvLs had effective cell uptake and reduced activation of HSCs. Rats that were injected with CCl4 by intraperitoneal injection for 6 weeks exhibited obvious symptoms of liver fibrosis and were treated with systemically administered sEvLs and free sEvs for 4 weeks. Rats injected with olive oil alone served as sham controls. Administration of sEvLs significantly reduced the area of fibrosis compared with free sEvs. We demonstrated that sEvLs inhibited HSCs activation and ECM production, and promote ECM degradation by downregulating α-smooth muscle actin (α-SMA), collagen I, tissue inhibitor of metalloproteinase (TIMP) -1 and upregulating matrix metalloprotease (MMP) -1. In summary, as an endogenous delivery vehicle, sEvs could deliver mRNA to attenuate hepatic fibrosis by blocking the TGF-ß/Smad signaling pathway.

10.
Asian J Pharm Sci ; 17(2): 193-205, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35582642

RESUMO

As an important means of communication among cells, exosomes are being studied more and more widely, especially in the context of cancer immunotherapy. In the phase of tumor immunoediting, exosomes derived from tumor cells and different immune cells have complex and changeable physiological functions, because they carry different proteins and nucleic acid from the source cells. Based on the role of exosomes in the communication between different cells, cancer treatment methods are also under continuous research. This review briefly introduces the molecular composition of exosomes, which is closely related to their secretion mechanism. Subsequently, the role of exosomes encapsulating different information molecules is summarized. The role of exosomes in the three phases of tumor immunoediting is introduced in detail, and the relevant literature of exosomes in the tumor immune microenvironment is summarized by using a novel framework for extracting relevant documents. Finally, it summarizes the various exosome-based immunotherapies currently proposed, as well as the challenges and future prospects of exosomes in tumor immunotherapy.

11.
Small ; 18(16): e2107690, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35277914

RESUMO

Triple-negative breast cancer (TNBC) is the most lethal subtypes of breast cancer. Although chemotherapy is considered the most effective strategy for TNBC, most chemotherapeutics in current use are cytotoxic, meaning they target antiproliferative activity but do not inhibit tumor cell metastasis. Here, a TNBC-specific targeted liposomal formulation of epalrestat (EPS) and doxorubicin (DOX) with synergistic effects on both tumor cell proliferation and metastasis is described. These liposomes are biocompatible and effectively target tumor cells owing to hyaluronic acid (HA) modification on their surface. This active targeting, mediated by CD44-HA interaction, allows DOX and EPS to be delivered simultaneously to tumor cells in vivo, where they suppress not only TNBC tumor growth and the epithelial-mesenchymal transition, but also cancer stem cells, which collectively suppress tumor growth and metastasis of TNBC and may also act to prevent relapse of TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Ácido Hialurônico , Lipossomos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
12.
Food Addit Contam Part B Surveill ; 15(1): 31-37, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34596493

RESUMO

Tea is one of the most popular beverage in the world and may be contaminated by fungi and mycotoxins during processing. To analyse aflatoxin B1 (AFB1) and sterigmatocystin (STC) in three types of tea, a simple, fast, sensitive and reliable method of these two myxotoxins was developed. Recoveries obtained ranged from 95.9% to 118.0% and the RSDs were between 0.3% and 11.2%. The range of LODs was 0.2-0.45 µg/kg for AFB1 and 0.04-0.12 µg/kg for STC. The range of LOQs was 0.67-1.73 µg/kg for AFB1 and 0.13-0.40 µg/kg for STC. The optimised procedure was applied to analyse 126 tea samples randomly collected from different markets in China. AFB1 was not detected, but STC was determined in 17 samples with concentrations ranging from 0.13 to 4.48 µg/kg. The detection rate of STC was 5%, 8.9% and 33.3% in black tea, green tea and Oolong tea, respectively.


Assuntos
Aflatoxina B1 , Esterigmatocistina , Aflatoxina B1/análise , Contaminação de Alimentos/análise , Limite de Detecção , Esterigmatocistina/análise , Chá
13.
Front Neurol ; 12: 680474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531812

RESUMO

The Rey-Osterrieth Complex Figure (ROCF) test is a commonly used neuropsychological assessment tool. It is widely used to assess the visuo-constructional ability and visual memory of neuropsychiatric disorders, including copying and recall tests. By drawing the complex figure, the functional decline of a patient in multiple cognitive dimensions can be assessed, including attention and concentration, fine-motor coordination, visuospatial perception, non-verbal memory, planning and organization, and spatial orientation. This review first describes the different versions and scoring methods of ROCF. It then reviews the application of ROCF in the assessment of visuo-constructional ability in patients with dementia, other brain diseases, and psychiatric disorders. Finally, based on the scoring method of the digital system, future research hopes to develop a new digital ROCF scoring method combined with machine learning algorithms to standardize clinical practice and explore the characteristic neuropsychological structure information of different disorders.

15.
Nat Biomed Eng ; 4(1): 69-83, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31844155

RESUMO

Exosomes are attractive as nucleic-acid carriers because of their favourable pharmacokinetic and immunological properties and their ability to penetrate physiological barriers that are impermeable to synthetic drug-delivery vehicles. However, inserting exogenous nucleic acids, especially large messenger RNAs, into cell-secreted exosomes leads to low yields. Here we report a cellular-nanoporation method for the production of large quantities of exosomes containing therapeutic mRNAs and targeting peptides. We transfected various source cells with plasmid DNAs and stimulated the cells with a focal and transient electrical stimulus that promotes the release of exosomes carrying transcribed mRNAs and targeting peptides. Compared with bulk electroporation and other exosome-production strategies, cellular nanoporation produced up to 50-fold more exosomes and a more than 103-fold increase in exosomal mRNA transcripts, even from cells with low basal levels of exosome secretion. In orthotopic phosphatase and tensin homologue (PTEN)-deficient glioma mouse models, mRNA-containing exosomes restored tumour-suppressor function, enhanced inhibition of tumour growth and increased survival. Cellular nanoporation may enable the use of exosomes as a universal nucleic-acid carrier for applications requiring transcriptional manipulation.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Eletroporação/métodos , Exossomos/metabolismo , Glioma/tratamento farmacológico , RNA Mensageiro/uso terapêutico , Animais , Células Cultivadas , Modelos Animais de Doenças , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , MicroRNAs/uso terapêutico , Nanotecnologia , RNA Mensageiro/metabolismo , Transdução de Sinais
16.
Medicine (Baltimore) ; 98(47): e17970, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764802

RESUMO

Alzheimer disease (AD) is the most common neurodegenerative disease in the world. The relationship between AD and homocysteine (Hcy) is contradictory.A community-based investigation was conducted to find patients with AD in a vitamin B deficient population (≥55 years old) in Lüliang area in China. Venous blood samples were collected. Serum Hcy, folate, and vitamin B12 were measured. For each case, 4 controls were selected matched with age to evaluate the relationship between Hcy and AD.The crude prevalence of AD among people ages 55 years or older in this area was 8.60%. There were significant differences in serum Hcy and B12 between the case and control groups. We found that the higher level of serum Hcy was associated with a high risk of AD, and higher education level, higher folate and B12 concentration were protective factors to AD.Adjustment of diet structure and supplementation of folate and B12 may offer potential therapeutic measures in this area.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/etiologia , Disfunção Cognitiva/sangue , Disfunção Cognitiva/etiologia , Deficiência de Ácido Fólico/sangue , Deficiência de Ácido Fólico/complicações , Ácido Fólico/sangue , Homocisteína/sangue , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/complicações , Vitamina B 12/sangue , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Molecules ; 24(19)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31574945

RESUMO

Glioma is one of the most aggressive and common malignant brain tumors. Due to the presence of the blood-brain barrier (BBB), the effectiveness of therapeutics is greatly affected. In this work, to develop an efficient anti-glioma drug with targeting and which was able to cross the BBB, cell-penetrating peptides (R8) and transferrin co-modified doxorubicin (DOX)-loaded liposomes (Tf-LPs) were prepared. Tf-LPs possessed a spherical shape and uniform size with 128.64 nm and their ξ-potential was 6.81 mV. Tf-LPs were found to be stable in serum within 48 h. Uptake of Tf-LPs in both U87 and GL261 cells was analyzed by confocal laser scanning microscopy and by flow cytometry. Tf-LPs were efficiently taken up by both U87 and GL261 cells. Moreover, Tf-LPs exhibited sustained-release. The cumulative release of DOX from Tf-LPs reached ~50.0% and showed excellent anti-glioma efficacy. Histology of major organs, including brain, heart, liver, spleen, lungs and kidney, and the bodyweight of mice, all indicated low toxicity of Tf-LPs. In conclusion, Tf-LPs showed great promise as an anti-glioma therapeutic agent.


Assuntos
Antineoplásicos/administração & dosagem , Peptídeos Penetradores de Células/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Transferrina/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos , Camundongos , Polietilenoglicóis/administração & dosagem , Transferrina/química , Ensaios Antitumorais Modelo de Xenoenxerto
18.
BMJ Open ; 9(6): e027154, 2019 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-31209090

RESUMO

OBJECTIVES: To investigate the prevalence of mild cognitive impairment and the relationship with plasma aluminium among aluminium workers. DESIGN: This was a cross-sectional case-control study in the SH Aluminium Factory, China. SETTING: The university and affiliated hospital cooperated in the study. PARTICIPANTS: There were 910 aluminium workers on duty, among whom 853 participated in our study. Participants, such as those with cerebral vascular disease, epilepsy, brain trauma, Parkinson's and mental diseases, aluminium-containing drug and mental drug use, and any family history of dementia in first-degree relatives were excluded. PRIMARY AND SECONDARY OUTCOME MEASURES: Blood samples were collected, and plasma aluminium was measured by inductively coupled plasma-mass spectrometry. For each case, four age-matched controls were evaluated to determine the relationship between aluminium exposure and mild cognitive impairment. Conditional logistic regression was used to explore influential factors in mild cognitive impairment. RESULTS: Among 910 workers, 93.74% participated in stage 1; 53 cases were finally diagnosed. The crude prevalence of mild cognitive impairment among aluminium workers on duty was 6.21%. There was a significant difference in plasma aluminium concentration between the two groups. In the multivariate analysis, we found that a higher level of plasma aluminium was associated with a high risk of cognitive impairment when compared with a lower aluminium level (AOR=2.24, 95% CI=1.17 to 4.26), and a high education level was a protective factor (AOR=0.36, 95% CI=0.18 to 0.70). No other factor was statistically significant. CONCLUSIONS: Mild cognitive impairment is no longer a disease specific to elderly people. High plasma aluminium exposure might be associated with an increased risk of cognitive impairment, but a reduced risk was observed with a high education level. The cognitive function of aluminium workers on duty must be considered seriously.


Assuntos
Alumínio/sangue , Disfunção Cognitiva/epidemiologia , Exposição Ocupacional/efeitos adversos , Adulto , Alumínio/toxicidade , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Humanos , Masculino , Metalurgia , Pessoa de Meia-Idade
19.
Int J Pharm ; 564: 214-224, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31004717

RESUMO

Gene therapy strategies for liver cancer have broad application prospects but still lack a stable and efficient delivery vehicle. To overcome this obstacle, we designed a multifunctional gene delivery vector, sTPssOLP, which was based on oleylamine (OA)-modified disulfide-containing polyethylenimine (PEI) and incorporated into lipids to prepare a lipid nanoparticle. sTPssOLP consisted of the core of PEI derivative and cationic lipids bound to siRNA. The modified polyethylene glycol (PEG) and transferrin (Tf) were partially embedded in the phospholipid bilayer through the lipid and the other as the outer shell. The aim was to use the redox responsiveness of disulfide to trigger siRNA release in cytoplasm to enhance transfection efficiency. Pegylated lipids and Tf focus on increasing cycle life in the body and increasing accumulation at the tumor site of the carrier. In addition, two vectors were prepared as controls, one based on a PEI derivative containing no disulfide bond (POLP) and the other on the surface of the carrier not linked to Tf (PssOLP). PEI derivatives effectively avoid the toxicity problems caused by the use of PEI alone (25 kDa). Meanwhile, it was confirmed by gel retardation experiments that in the presence of dithiothreitol (DTT), the disulfide bond can indeed be reduced and the siRNA entrapped in the vector can be released. Both HepG2 and SMMC had significant uptake of sTPssOLP. The results of intracellular and lysosomal co-localization indicated that sTPssOLP achieved lysosomal escape. RT-PCR and Western blot results also confirmed that sTPssOLP had the best gene silencing activity. In vivo, the tumor inhibition rate of sTPssOLP in nude mice carrying HepG2 xenografts was 56%, which was significantly greater than that of the saline control group. In vivo imaging results showed that fluorescently labeled siRNA loaded in sTPssOLP was able to deliver more to the tumor site. At the same time, it was observed that sTPssOLP did not show significant damage to normal tissues. Therefore, this multifunctional gene delivery vector warrants further investigation.


Assuntos
Portadores de Fármacos/administração & dosagem , Terapia Genética , Neoplasias Hepáticas/terapia , RNA Interferente Pequeno/administração & dosagem , Aminas/administração & dosagem , Animais , Carbocianinas , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Feminino , Corantes Fluorescentes , Técnicas de Transferência de Genes , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Transferrina/administração & dosagem
20.
Int J Nanomedicine ; 14: 135-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30613142

RESUMO

BACKGROUND: We previously developed cabazitaxel (CTX)-loaded human serum albumin nanoparticles (NPs-CTX) via a self-assembly method, and these NPs showed efficacy in prostate cancer therapy. Many studies have shown that the levels of folic acid (FA) receptor on the surface of various tumor cells are high. Therefore, FA-modified NPs-CTX may have enhanced antitumor effects compared with unmodified NPs-CTX. METHODS: NPs-CTX were first prepared via self-assembly, and FA was conjugated on the surface of NPs-CTX through the -NH2 groups of the NPs to produce FA-NPs-CTX. The FA-NPs-CTX were evaluated in tumor cells with high FA receptor (FR) expression in vitro and in vivo. RESULTS: Both NPs-CTX and FA-NPs-CTX exhibited good stability and morphology. Drug release from the NPs was not affected by FA conjugation. Compared with CTX dissolved in a mixture of Tween 80 and 13% ethanol (w/w) at a ratio of 1:4 (v/v) (Tween-CTX), the two nanoformulations had lower lytic activity against normal red blood cells. However, FA-NPs-CTX showed greater inhibition of tumor cells with overexpressed FR, compared with NPs-CTX, in the cytotoxicity experiments. Moreover, the cellular uptake of FA-NPs-CTX was enhanced through FR-mediated endocytosis in HeLa cells in vitro and HeLa xenograft tumors in vivo. Although Tween-CTX exhibited tumor growth inhibition similar to FA-NPs-CTX in vivo, this inhibition also caused adverse side effects; the median lethal dose (LD50) of Tween-CTX to mice was 5.68 mg/kg, while FA-NPs-CTX-treated mice survived at doses exceeding 400 mg/kg. CONCLUSION: The results showed that FA-NPs-CTX caused inhibition of tumor growth in a manner similar to that of Tween-CTX; however, the safety and tolerability of CTX were greatly improved by FA conjugation compared with those of Tween-CTX. In summary, FA-NPs-CTX have great potential in CTX delivery, and this formulation is a promising candidate for the treatment of cancers with high FR levels.


Assuntos
Sistemas de Liberação de Medicamentos , Receptor 2 de Folato/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Albumina Sérica Humana/metabolismo , Taxoides/uso terapêutico , Células A549 , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Endocitose , Feminino , Ácido Fólico/metabolismo , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/patologia , Taxoides/farmacologia , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
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