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1.
ACS Appl Bio Mater ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651918

RESUMO

The combination of small-interfering RNA (siRNA)-mediated gene silencing and chemotherapeutic agents for lung cancer treatment has attracted widespread attention in terms of a greater therapeutic effect, minimization of systemic toxicity, and inhibition of multiple drug resistance (MDR). In this work, three amphiphiles, CBN1-CBN3, were first designed and synthesized as a camptothecin (CPT) conjugate and gene condensation agents by the combination of CPT prodrugs and di(triazole-[12]aneN3) through the ROS-responsive phenylborate ester and different lengths of alkyl chains (with 6, 9, 12 carbon chains for CBN1-CBN3, respectively). CBN1-CBN3 were able to be self-assembled into liposomes with an average diameter in the range of 320-240 nm, showing the ability to effectively condense siRNA. Among them, CBN2, with a nine-carbon alkyl chain, displayed the best anticancer efficiency in A549 cells. In order to give nanomedicines a stealth property and PEGylation/dePEGylation transition, a GSH-responsive PEGylated TPE derivative containing a disulfide linkage (TSP) was further designed and prepared. A combination of CBN2/siRNA complexes and DOPE with TSP resulted in GSH/ROS dual-responsive lipid-polymer hybrid nanoparticles (CBN2-DP/siRNA NPs). In present GSH and H2O2, CBN2-DP/siRNA NPs were decomposed, resulting in the controlled release of CPT drug and siRNA. In vitro, CBN2-DP/siPHB1 NPs showed the best anticancer activity for suppression of about 75% of A549 cell proliferation in a serum medium. The stability of CBN2-DP/siRNA NPs was significantly prolonged in blood circulation, and they showed effective accumulation in the A549 tumor site through an enhanced permeability and retention (EPR) effect. In vivo, CBN2-DP/siPHB1 NPs demonstrated enhanced synergistic cancer therapy efficacy and tumor inhibition as high as 71.2%. This work provided a strategy for preparing lipid-polymer hybrid NPs with GSH/ROS dual-responsive properties and an intriguing method for lung cancer therapy.

2.
J Mater Chem B ; 11(37): 8943-8955, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37727888

RESUMO

A novel dual-responsive nanoparticle (NP) system was aimed to be developed for the co-delivery of camptothecin (CPT) and plasmid encoding TNF-related apoptosis-inducing ligand (pTRAIL) DNA in cancer therapy. The combination of the prodrug CPT and the nucleic acid condensing di-(triazole-[12]aneN3) unit with 4-nitrobenzyl ester through alkyl chains resulted in three nitroreductase (NTR) responsive amphiphiles, CNN1-CNN3 (with 5, 8, and 11 carbon chains, respectively). Among them, CNN2 was the most effective in inhibiting the proliferation of HeLa cells in the presence of fusogenic lipid DOPE. The NPs composed of CNN2, pDNA, and DOPE were further co-assembled with ROS-responsive thioketal-linked amphiphilic polymer (TTP) to afford the core-shell NPs (CNN2-DT/pDNA) with an average size of 118 nm, which exhibited high drug-loading capacity, excellent serum tolerance, and good biocompatibility. In the presence of ROS, NTR, and NADH, the core-shell NPs were decomposed, leading to the efficient release of 80% CPT and abundant pDNA. The self-assembly and delivery process of CNN2-DT NPs and DNA were clearly observed through the AIE fluorescent imaging. In vitro and in vivo results demonstrated that the CNN2-DT/pTRAIL NPs synergistically promoted 68% apoptosis of tumor cells and inhibited tumor growth with negligible toxic side effects. This study showed that the combination of prodrug and nucleic acid through dual-responsive core-shell NPs provide a spatially and temporally-controlled strategy for cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Ácidos Nucleicos , Pró-Fármacos , Humanos , Células HeLa , Pró-Fármacos/farmacologia , Espécies Reativas de Oxigênio , Nitrorredutases , Camptotecina/farmacologia , Polietilenoglicóis
3.
Bioconjug Chem ; 34(1): 248-256, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36621834

RESUMO

Enzyme-responsive drug delivery systems have drawn much attention in the field of cancer theranostics due to their high sensitivity and substrate specificity under mild conditions. In this study, an amphiphilic polymer T1 is reported, which contains a tetraphenylethene unit and a poly(ethylene glycol) chain linked by an esterase-responsive phenolic ester bond. In aqueous solution, T1 formed stable micelles via self-assembly, which showed an aggregation-induced emission enhancement of 32-fold at 532 nm and a critical micelle concentration of 0.53 µM as well as esterase-responsive activity. The hydrophobic drug doxorubicin (DOX) was efficiently encapsulated into the micelles with a drug loading of 21%. In the presence of the esterase, the selective decomposition of drug-loaded T1 micelles was observed, and DOX was subsequently released with a half-life of 5 h. In vitro antitumor studies showed that T1@DOX micelles exhibited good therapeutic effects on HeLa cells, while normal cells remained mostly intact. In vivo anticancer experiments revealed that T1@DOX micelles indeed suppressed tumor growth and had reduced side effects compared to DOX·HCl. The present work showed the potential clinical application of esterase-responsive drug delivery in cancer therapy.


Assuntos
Micelas , Polietilenoglicóis , Humanos , Polietilenoglicóis/química , Células HeLa , Esterases , Portadores de Fármacos/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Polímeros/química , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio
4.
J Clin Endocrinol Metab ; 107(9): 2530-2538, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35758857

RESUMO

CONTEXT: Evidence has shown maternal androgen levels in both the general population and populations with hyperandrogenic disorders are inversely associated with offspring birth weight. CONTEXT: We aimed to investigate the causal effect of maternal testosterone levels in the general population on offspring birth weight and preterm delivery risk using a two-sample Mendelian randomization (MR) method. METHODS: We obtained independent genetic instruments from a sex-specific genome-wide association study with up to 230 454 females of European descent from the UK Biobank. Genetic instruments with consistent testosterone effects but no aggregate effect on sex hormone-binding globulin were used to perform the main analysis. Summary-level data of offspring birth weight adjusted for genotype were obtained from a study with 210 406 females of European descent. Summary-level data of preterm delivery were obtained from the FinnGen study (6736 cases and 116 219 controls). RESULTS: MR analysis showed that each SD (0.62 nmol/L) increase in testosterone levels could reduce the offspring birth weight by 37.26 g (95% CI, 19.59-54.94 g; P = 3.62 × 10-5). Each SD increase in testosterone levels was also associated with an increased risk of preterm delivery (odds ratio = 1.329; 95% CI, 1.161-1.520; P = 3.57 × 10-5). Similar results were found using different MR methods and multivariable MR analyses. CONCLUSION: This two-sample MR study showed genetically determined higher circulating testosterone levels in females from the general population were associated with low birth weight of offspring and increased risk of preterm delivery.


Assuntos
Análise da Randomização Mendeliana , Nascimento Prematuro , Peso ao Nascer/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/genética , Testosterona
5.
Bioorg Chem ; 119: 105559, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34952244

RESUMO

Stimuli-responsive drug delivery systems (DDSs) based on amphiphilic polymers have attracted much attention. In this study, we reported an innovative H2O2-responsive amphiphilic polymer (TBP), bearing a H2O2-sensitive phenylboronic ester, AIE fluorophore tetraphenylethene (TPE) hydrophobic, and polyethylene glycol hydrophilic (PEG) moieties. TBP could self-assemble into micelles with an encapsulation efficiency as high as 74.9% for doxorubicin (DOX) in aqueous solution. In the presence of H2O2, TBP micelles was decomposed by oxidation, hydrolysis and rearrangement, leading to almost 80% DOX release from TBP@DOX micelles. TBP and the corresponding degradation products were biocompatible, while TBP@DOX micelles only displayed obvious toxicity toward cancer cells. Drug delivery process was clearly monitored by confocal laser scanning microscopic (CLSM) and flow cytometry (FCM) analysis. Moreover, in vivo anticancer study showed that TBP@DOX micelles were accumulated in tumor region of nude mice and effectively inhibited tumor growth. The results suggested that the reported H2O2-responsive amphiphilic polymer displayed great potential in drug delivery and tumor therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Peróxido de Hidrogênio/química , Polímeros/química , Tensoativos/química , Animais , Antibióticos Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Agregados Proteicos , Relação Estrutura-Atividade
6.
Org Biomol Chem ; 19(19): 4359-4363, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33908557

RESUMO

A series of unnatural tripeptides, each consisting of two aromatic γ-amino acid residues and an ϖ-amino acid residue, are designed to probe their folding into hairpin conformations. The ϖ-amino acid residues, with aliphatic or aromatic spacers of different sizes, serve as the loop of the hairpins. Studies based on one-dimensional (1D) 1H NMR performed at different concentrations, solvent polarity, and temperature, along with 2D-NMR studies, demonstrated that the doubly H-bonded aromatic γ-amino acid residues play important roles in driving these tripeptides into the hairpin conformation. The loop based on 5-aminovaleric acid, which offers a four-carbon (CH2)4 spacer, enhanced the stability of the corresponding hairpin, while loops having a shorter, a longer and a more rigid spacer disfavored the formation of the hairpins. Results from computational studies are in good agreement with the experimental observations. Furthermore, the crystal structure of peptide 1b revealed the expected hairpin conformation in the solid state. This turn motif, which contains H-bonded aromatic γ-amino acid residues as the core unit and an ϖ-amino acid residue serving as the loop, provides a new platform that can be used to obtain a variety of turn conformations by incorporating diverse amino acids into the loops.

7.
Stem Cell Res Ther ; 11(1): 214, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493435

RESUMO

BACKGROUND: Multiple studies have reported that mesenchymal stem cell (MSC) therapy has beneficial effects in experimental models of sepsis. However, this finding remains inconclusive. This study was performed to systematically determine the connection between MSC therapy and mortality in sepsis animal models by pooling and analyzing data from newly published studies. METHODS: A detailed search of related studies from 2009 to 2019 was conducted in four databases, including MEDLINE, EMBASE, Cochrane Library, and Web of Science. After browsing and filtering out articles that met the inclusion criteria for statistical analysis, the inverse variance method of the fixed effects model was used to calculate the pooled odds ratios (ORs) and their 95% confidence intervals (CIs). RESULTS: Twenty-nine animal studies, including 1266 animals, were identified. None of the studies was judged to have a low risk of bias. The meta-analysis demonstrated that MSC therapy was related to a significantly lower mortality rate (OR 0.29, 95% CI 0.22-0.38, P < 0.001). Subgroup analyses performed based on the MSC injection dose (< 1.0 × 106 cells, OR = 0.33, 95% CI 0.20-0.56, P < 0.001; 1.0 × 106 cells, OR = 0.24, 95% CI 0.16-0.35, P < 0.001) and injection time (< 1 h, OR = 0.24, 95% CI 0.13-0.45, P < 0.001; 1 h, OR = 0.28, 95% CI 0.17-0.46, P < 0.001) demonstrated that treatment with MSCs significantly reduced the mortality rate of animals with sepsis. CONCLUSION: This up-to-date meta-analysis showed a connection between MSC therapy and lower mortality in sepsis animal models, supporting the potential therapeutic effect of MSC treatment in future clinical trials. The results in this study contradict a previous meta-analysis with regards to the ideal dose of MSC therapy. Thus, further research is required to support these findings.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Sepse , Animais , Sepse/terapia
8.
Org Biomol Chem ; 17(22): 5570-5577, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31114827

RESUMO

Nano drug delivery is a promising domain in biomedical theranostics and has aroused more and more attention in recent years. We report here an amphiphilic polymer TPG1, bearing a H2O2-sensitive benzil and an AIE fluorophore tetraphenylethene (TPE) unit, which is able to self-assemble into spherical nanosized micelles in aqueous solution. Doxorubicin (DOX) can be encapsulated into TPG1 micelles efficiently with the loading capability of up to 59% by weight. The benzil moiety could be cleaved via the Baeyer-Villiger type reaction in the presence of H2O2, leading to the decomposition of TPG1 micelles and release of DOX. In vitro studies indicated that DOX-loaded TPG1 micelles can be internalized by cancer cells, followed by unloading encapsulated DOX under the stimulation of H2O2. The drug release process can be monitored by the AIE fluorescence from the degradation products containing a TPE moiety. MTT assays against HeLa and HepG2 cancer cells demonstrated that DOX-loaded micelles showed good anticancer efficacy. The polymer TPG1 and the corresponding decomposed products showed great biocompatibility. Our data suggest that TPG1 has the potential to be employed for the controlled drug delivery system.


Assuntos
Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Corantes Fluorescentes/química , Peróxido de Hidrogênio/farmacologia , Fenilglioxal/análogos & derivados , Polímeros/farmacologia , Estilbenos/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Células HeLa , Células Hep G2 , Humanos , Peróxido de Hidrogênio/química , Micelas , Estrutura Molecular , Imagem Óptica , Fenilglioxal/química , Fenilglioxal/farmacologia , Polímeros/química
9.
Zhen Ci Yan Jiu ; 43(2): 114-7, 2018 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-29516700

RESUMO

OBJECTIVE: To observe the effect of manual acupuncture stimulation of different layers (skin, muscle, peritoneum, sub-peritoneum) of "Tianshu" (ST 25) region on proximal colonic pressure in normal rats. METHODS: Forty-eight male SD rats were divided into 6 groups: all layer-needling, brushing, cutaneous needling, muscular needling, peritoneum-needling and sub-peritoneum-needling groups (n=8 in each group). Manual needling or brushing was applied to "Tianshu" (ST 25) region. The colonic internal pressure was measured by using an amplifier and a pressure transducer-connected balloon which was implanted into the colonic cavity about 6 cm from the ileocecal valve. For rats of the all-layer needling group, an acupuncture needle was inserted into ST 25 about 1 cm deep and rotated for a while, for rats of the brushing group, a Chinese calligraphy brush pen was used to brush the skin hair for 1 min. For rats of the rest 4 groups, an acupuncture needle was inserted into the skin, muscle layer after cutting open the skin (about 0.1 cm), the peritoneum layer after cutting open the skin and muscle layers, and the sub-peritoneum layer after cutting open the skin, muscle and peritoneum layers, respectively, and rotated using the uniform reinforcing-reducing technique for about 1 min at a frequency of 120 twirlings per minute every time. RESULTS: During manual needling stimulation of the full layers, cutaneous layer, muscle layer, peritoneum layer and the sub-peritoneum layer of bilateral "Tianshu" (ST 25), the internal pressure of proximal colon was significantly decreased relevant to pre-stimulation in each group (P<0.05), and there were no significant differences between bilateral sides needling stimulation in the decreased pressure levels (P>0.05). During hair brushing of ST 25 region, the colonic pressure was observably increased relevant to pre-needling stimulation (P<0.05). One min after the acupuncture stimulation, the decreased pressures maintained in needling the all-layer on the left side, needling the skin on the right side, needling the peritoneum layer on both sides, and needling the sub-peritoneum layer on both sides relevant to the brushing group of the same side (P<0.05). CONCLUSION: Manual acupuncture stimulation of each layer tissue of ST 25 on both sides may lower internal pressure of proximal colon in normal rats, suggesting their involvement of acupuncture effect in relaxing proximal colonic contraction.


Assuntos
Terapia por Acupuntura , Animais , Colo , Masculino , Agulhas , Ratos , Ratos Sprague-Dawley
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