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1.
Biomacromolecules ; 25(2): 1171-1179, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38181417

RESUMO

The development of nonviral dendritic polymers with a simple molecular backbone and great gene delivery efficiency to effectively tackle cancer remains a great challenge. Phosphorus dendrimers or dendrons are promising vectors due to their structural uniformity, rigid molecular backbones, and tunable surface functionalities. Here, we report the development of a new low-generation unsymmetrical cationic phosphorus dendrimer bearing 5 pyrrolidinium groups and one amino group as a nonviral gene delivery vector. The created AB5-type dendrimers with simple molecular backbone can compress microRNA-30d (miR-30d) to form polyplexes with desired hydrodynamic sizes and surface potentials and can effectively transfect miR-30d to cancer cells to suppress the glycolysis-associated SLC2A1 and HK1 expression, thus significantly inhibiting the migration and invasion of a murine breast cancer cell line in vitro and the corresponding subcutaneous tumor mouse model in vivo. Such unsymmetrical low-generation phosphorus dendrimers may be extended to deliver other genetic materials to tackle other diseases.


Assuntos
Dendrímeros , MicroRNAs , Neoplasias , Animais , Camundongos , Dendrímeros/química , Vetores Genéticos , MicroRNAs/genética , Técnicas de Transferência de Genes , Cátions , Fósforo
2.
ACS Nano ; 17(23): 23889-23902, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38006397

RESUMO

Development of a nanoscale drug delivery system that can simultaneously exert efficient tumor therapeutic efficacy while creating the desired antitumor immune responses is still challenging. Herein, we report the use of a manganese dioxide (MnO2)-entrapping dendrimer nanocarrier to codeliver glucose oxidase (GOx) and cyclic GMP-AMP (cGAMP), an agonist of the stimulator of interferon genes (STING) for improved tumor chemodynamic/starvation/immune therapy. Methoxy poly(ethylene glycol) (mPEG)- and phenylboronic acid (PBA)-modified generation 5 (G5) poly(amidoamine) dendrimers were first synthesized and then entrapped with MnO2 nanoparticles (NPs) to generate the hybrid MnO2@G5-mPEG-PBA (MGPP) NPs. The created MGPP NPs with an MnO2 core size of 2.8 nm display efficient glutathione depletion ability, and a favorable Mn2+ release profile under a tumor microenvironment mimetic condition to enable Fenton-like reaction and T1-weighted magnetic resonance (MR) imaging. We show that the MGPP-mediated GOx delivery facilitates enhanced chemodynamic/starvation therapy of cancer cells in vitro, and further codelivery of cGAMP can effectively trigger immunogenic cell death (ICD) to strongly promote the maturation of dendritic cells. In a bilateral mouse colorectal tumor model, the dendrimer delivery nanosystem elicits a potent antitumor performance with a strong abscopal effect, greatly improving the overall mouse survival rate. Importantly, the dendrimer-mediated codelivery not only allows the coordination of Mn2+ with GOx and cGAMP for respective chemodynamic/starvation-triggered ICD and augmented STING activation to boost systemic antitumor immune responses, but also enables T1-weighted tumor MR imaging, potentially serving as a promising nanoplatform for enhanced antitumor therapy with desired immune responses.


Assuntos
Neoplasias Colorretais , Dendrímeros , Nanopartículas , Neoplasias , Animais , Camundongos , Compostos de Manganês/farmacologia , Nucleotídeos , Óxidos , Imageamento por Ressonância Magnética , Glucose Oxidase , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Modelos Animais de Doenças , Espectroscopia de Ressonância Magnética , Microambiente Tumoral
3.
J Mater Chem B ; 11(21): 4808-4818, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37212531

RESUMO

It remains an extreme challenge to develop multifunctional drug delivery systems with tumor specificity and a tumor microenvironment (TME) remodeling ability for achieving improved chemotherapy against malignant tumors. Herein, we report the design of diselenide-crosslinked poly(N-vinylcaprolactam) (PVCL) nanogels (NGs) co-loaded with gold (Au) nanoparticles (NPs) and methotrexate (MTX) as a multifunctional nanoplatform (for short, MTX/Au@PVCL NGs) for improved chemotherapy and computed tomography (CT) imaging of tumors. The designed MTX/Au@PVCL NGs show excellent colloidal stability under physiological conditions, while dissociating rapidly to release the incorporated Au NPs and MTX in the H2O2-abundant and slightly acidic TME. The responsive release of Au NPs and MTX effectively induces the apoptosis of cancer cells and prevents DNA replication, together contributing to the repolarization of macrophages from protumor M2-like to antitumor M1-like phenotype in vitro. The MTX/Au@PVCL NGs also enable the remodeling of tumor-associated macrophages to the M1-like phenotype in vivo in a subcutaneous mouse melanoma model, which increases the recruitment of effector T lymphocytes and reduces the content of immunosuppressive regulatory T cells to achieve synergistically enhanced antitumor efficacy when combined with MTX-mediated chemotherapy. Moreover, the MTX/Au@PVCL NGs can be used for Au-mediated CT imaging of tumors. The thus developed NG platform shows great promise as an updated nanomedicine formulation for immune modulation-enhanced tumor chemotherapy under the guidance of CT imaging.


Assuntos
Nanopartículas Metálicas , Neoplasias , Camundongos , Animais , Metotrexato , Nanogéis/uso terapêutico , Ouro/uso terapêutico , Peróxido de Hidrogênio/uso terapêutico , Neoplasias/tratamento farmacológico , Tomografia Computadorizada por Raios X/métodos , Microambiente Tumoral
4.
J Control Release ; 355: 171-183, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36736909

RESUMO

Tumor vaccine that can effectively activate or strengthen the body's antitumor immune response to kill and eliminate tumor cells has attracted widespread attention. Currently developed tumor vaccines have severe shortcomings such as low bioavailability and lack of dual or multiple functions, resulting in poor antitumor efficacy. Herein, we report the development of an advanced nanosystem integrated with phenylboronic acid (PBA)-functionalized poly(amidoamine) dendrimers of generation 5 (G5), copper sulfide nanoparticles, and cyclic GMP-AMP (cGAMP), an immune adjuvant (for short, G5-PBA@CuS/cGAMP) to act as a photothermal-triggered nanovaccine. We show that the prepared functional nanosystem possesses an average CuS core size of 3.6 nm, prominent near-infrared absorption feature to have an excellent photothermal conversion efficiency of 44.0%, and good protein adsorption characteristics due to the PBA modification. With these features, the developed nanosystem can be adopted for photothermal therapy of primary melanoma tumors and simultaneously absorb the whole tumor cell antigens, thus creating photothermal-triggered dendrimeric nanovaccine of G5-PBA@CuS/cGAMP/antigen in situ to induce antitumor immune response to inhibit the distal tumors as well. Meanwhile, melanoma cells treated with the G5-PBA@CuS in vitro under laser irradiation allowed the creation of G5-PBA@CuS/antigen complexes that could be further integrated with cGAMP to form preformed nanovaccine for effective primary tumor inhibition and tumor occurrence prevention. The designed photothermal-triggered dendrimeric nanovaccine may represent an advanced nanomedicine formulation to effectively inhibit the growth of primary and distal tumors, and prevent tumor occurrence through the stimulated systemic antitumor immunity.


Assuntos
Dendrímeros , Melanoma , Nanopartículas , Neoplasias , Humanos , Fototerapia , Neoplasias/terapia , Neoplasias/patologia , Sulfetos , Cobre
5.
Biochem Genet ; 57(4): 555-570, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30734883

RESUMO

Camellia sinensis (L.) O. Kuntze is one of the most important non-alcoholic beverage crops in Asian and African countries. In recent years, many green tea cultivars have been released and played an important role in improving the production and quality of tea trees. The objectives of this study were to assess the genetic diversity of the eighteen main green tea cultivars in Zhejiang Province-the most famous green tea-producing area of China-using start codon-targeted (SCoT) markers and to develop a specific sequence-characterized amplified region (SCAR) marker for application in cultivar diagnosis. Thirty-one SCoT primers produced 264 loci, 226 of which were polymorphic. The genetic similarity coefficients among these green tea cultivars ranged from 0.587 to 0.814, indicating that a high level of genetic diversity was present. Both a UPGMA dendrogram and a PCoA plot grouped the tea cultivars into three groups. The partitioning of groups in the UPGMA and PCoA was similar, and much of the clustering was highly consistent with the classification of tea cultivars according to their genetic backgrounds. A unique SCoT band, SCoT4-1649, specific to the tea cultivar 'Yingshuang,' was transformed into a SCAR marker. This SCAR marker is highly useful for the identification and germplasm conservation of green tea cultivars.


Assuntos
Camellia sinensis/genética , Sequência de Bases , China , Códon de Iniciação , Primers do DNA/genética , DNA de Plantas/genética , Marcadores Genéticos , Variação Genética , Melhoramento Vegetal , Reação em Cadeia da Polimerase , Chá/genética
6.
J Agric Food Chem ; 67(8): 2408-2419, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30721059

RESUMO

The effects of blue (BL) and green light (GL) treatment during the dark period were examined in Camellia sinensis as a first step to understanding the spectral effects of artificial BL and GL on plant secondary metabolism and light signaling interactions. BL could induce the expression of CRY2/3, SPAs, HY5, and R2R3-MYBs to promote the accumulation of anthocyanins and catechins in tea plants. GL, on the other hand, could stimulate the accumulation of several functional substances (e.g., procyanidin B2/B3 and l-ascorbate) and temper these BL responses via down-regulation of  CRY2/3 and PHOT2. Furthermore, the molecular events that triggered by BL and GL signals were partly overlapped with abiotic/biotic stress responses. We indicate the possibility of a targeted use of BL and GL to regulate the amount of functional metabolites to enhance tea quality and taste, and to potentially trigger defense mechanisms of tea plants.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/efeitos da radiação , Flavonoides/biossíntese , Folhas de Planta/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chá/química , Transcriptoma/efeitos da radiação
8.
Front Plant Sci ; 8: 2104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312376

RESUMO

Tea leaf color is not only important from an aesthetics standpoint but is also related to tea quality. To investigate the molecular mechanisms that determine tea leaf color, we examined Camellia sinensis cv. 'Anjin Baicha' (an albino tea cultivar) by tandem mass tag isobaric labeling to generate a high-resolution proteome and acetyl-proteome atlas of three leaf developmental stages. We identified a total of 7,637 proteins and quantified 6,256; of these, 3,232 were classified as differentially accumulated proteins (DAPs). We also identified 3,161 lysine acetylation sites in 1,752 proteins and quantified 2,869 in 1,612 proteins. The acetylation levels at 468 sites were significantly altered across the three developmental stages during periodic albinism; the corresponding proteins were associated with a variety of biological processes. Interestingly, a large number of DAPs and acetylated proteins with increased/decreased acetylation were related to photosynthesis and secondary metabolite biosynthetic pathways, suggesting that the accumulation or acetylation level of these proteins regulates periodic albinism in 'Anjin Baicha.' Additionally, overlap between succinylome and acetylome among three 'Anjin Baicha' developmental stages were found. These data provide important insight into the mechanisms of leaf coloration in the tea plant. The mass spectrometry data have been deposited to Proteome X change via the PRIDE partner repository with the data set identifier PXD008134.

9.
Molecules ; 18(8): 9933-48, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23966080

RESUMO

Pinus koraiensis polysaccharides (PKP) were extracted by hot water from P. koraiensis pine cones. Five polysaccharide fractions named PKP-A, PKP-B, PKP-C, PKP-D and PKP-E were successfully separated at final ethanol concentrations of 30%, 50%, 60%, 70% and 80%, respectively. HPLC, FT-IR, GC-MS and automatic amino-acid analysis were applied to investigate their chemical characteristics. Monosaccharide component analysis indicated that the five fractions were all composed of D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose and D-galactose, but their molar ratios were quite different. HPLC results revealed that the polysaccharides precipitated by higher concentrations of ethanol solution had lower molecular masses. Moreover, the antioxidant activities of the five fractions were studied on the basis of hydroxyl radical and ABTS radical scavenging tests. The five graded polysaccharide fractions exhibited good inhibitory power, and MTT tests in vitro showed the IC50 of PKP-A and PKP-E were 1,072.5 and 2,070.0 µg · mL-1, respectively. These results demonstrated that the PKP could be a potential source of natural antioxidants or dietary supplements.


Assuntos
Etanol/química , Pinus/química , Polissacarídeos/química , Arabinose/química , Cromatografia Líquida de Alta Pressão , Galactose/química , Cromatografia Gasosa-Espectrometria de Massas , Glucose/química , Manose/química , Ribose/química , Espectroscopia de Infravermelho com Transformada de Fourier , Xilose/química
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