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1.
Environ Sci Technol ; 58(10): 4812-4823, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38428041

RESUMEN

Many studies have investigated activation of ferrate (Fe(VI)) to produce reactive high-valent iron intermediates to enhance the oxidation of micropollutants. However, the differences in the risk of pollutant transformation caused by Fe(IV) and Fe(V) have not been taken seriously. In this study, Fe(VI)-alone, Fe3+/Fe(VI), and NaHCO3/Fe(VI) processes were used to oxidize fluoroquinolone antibiotics to explore the different effects of Fe(IV) and Fe(V) on product accumulation and toxicity changes. The contribution of Fe(IV) to levofloxacin degradation was 99.9% in the Fe3+/Fe(VI) process, and that of Fe(V) was 89.4% in the NaHCO3/Fe(VI) process. The cytotoxicity equivalents of levofloxacin decreased by 1.9 mg phenol/L in the Fe(IV)-dominant process while they significantly (p < 0.05) increased by 4.7 mg phenol/L in the Fe(V)-dominant process. The acute toxicity toward luminescent bacteria and the results for other fluoroquinolone antibiotics also showed that Fe(IV) reduced the toxicity and Fe(V) increased the toxicity. Density functional theory calculations showed that Fe(V) induced quinolone ring opening, which would increase the toxicity. Fe(IV) tended to oxidize the piperazine group, which reduced the toxicity. These results show the different-pollutant transformation caused by Fe(IV) and Fe(V). In future, the different risk outcomes during Fe(VI) activation should be taken seriously.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Purificación del Agua , Fluoroquinolonas/toxicidad , Levofloxacino , Hierro , Oxidación-Reducción , Fenoles , Antibacterianos/toxicidad , Purificación del Agua/métodos
2.
Eur Radiol ; 32(10): 7108-7116, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35610386

RESUMEN

OBJECTIVES: To assess the predictive value of the combination of bone marrow (BM) proton density fat fraction (PDFF) and liver R2* for osteopenia and osteoporosis and the additional role of liver R2*. METHODS: A total of 107 healthy women were included between June 2019 and January 2021. Each participant underwent dual-energy X-ray absorptiometry (DXA) and chemical shift-encoded 3.0-T MRI. PDFF measurements were performed for each lumbar vertebral body, and R2* measurements were performed in liver segments. Agreement among measurements was assessed by Bland-Altman analysis. Receiver operating characteristic (ROC) curves were generated to select optimised cut-offs for BM PDFF and liver R2*. Univariable and multivariable logistic regressions were performed. The C statistic and continuous net reclassification improvement (NRI) were adopted to explore the incremental predictive ability of liver R2*. RESULTS: Bone mass decreased in 42 cases (39.3%) and nonbone mass decreased in 65 cases (60.7%). There were significant differences among the age groups, menopausal status groups, PDFF > 45.0% groups, and R2* > 67.7 groups. Each measurement had good reproducibility. The odds ratios (95% CIs) were 4.05 (1.22-13.43) for PDFF and 4.34 (1.41-13.35) for R2*. The C statistic (95% CI) without R2* was 0.888 (0.827-0.950), and with R2* was 0.900 (0.841-0.960). The NRI resulting from the combination of PDFF and R2* was 75.6% (p < 0.01). CONCLUSION: The predictive improvement over the use of BM PDFF and other traditional risk factors demonstrates the potential of liver R2* as a biomarker for osteopenia and osteoporosis in healthy women. KEY POINTS: • Liver R2* is a biomarker for the assessment of osteopenia and osteoporosis. • Liver R2* improved the ability to predict osteopenia and osteoporosis. • The intra- and interobserver measurements showed high agreement.


Asunto(s)
Enfermedades Óseas Metabólicas , Osteoporosis , Biomarcadores , Médula Ósea/diagnóstico por imagen , Femenino , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Osteoporosis/diagnóstico por imagen , Protones , Reproducibilidad de los Resultados , Cuerpo Vertebral
3.
Drug Dev Ind Pharm ; 48(1): 1-11, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35410574

RESUMEN

Genetic medicines hold great promise for treatment of a number of diseases; however, the development of effective gene delivery carrier is still a challenge. The commonly used gene carrier liposomes and cationic polymers have limited their clinical application due to their respective disadvantages. Lipid-polymer hybrid nanoparticles (LHNPs) are novel drug delivery system that exhibit complementary characteristics of both polymeric nanoparticles and liposomes. In this account, we developed the α-cyclodextrin-conjugated generation-2 polyamidoamine dendrimers-lipids hybrid nanoparticles (CDG2-LHNPs) for gene delivery. The pDNA/CDG2-LHNPs was stable during 15 days of storage period both at 4 °C, 25 °C, and 37 °C, whereas the particle size of pDNA/CDG2 and pDNA/liposomes dramatically increased after storage at 4 °C for 8 h. CDG2-LHNPs showed significantly superior transfection efficiencies compared to either CDG2 or liposomes. The mechanism of high transfection efficiency of pDNA/CDG2-LHNPs was further explored using pharmacological inhibitors chlorpromazine, filipin, and cytochalasion D. The result demonstrated that cell uptake of pDNA/CDG2-LHNPs was mediated by clathrin-mediated endocytosis (CME), caveolae-mediated endocytosis (CvME), and macropinocytosis together. pDNA/CDG2-LHNPs were more likely be taken up by cells through CvME, which avoided lysosomal degradation to a large extent. Moreover, the liposome component of pDNA/CDG2-LHNPs increased its cell uptake efficiency, and the CDG2 polymer component increased its proton buffer capacity, so the hybrid nanoparticles taken up by CME could also successfully escape from the lysosome. CDG2-LHNPs with stability and high-transfection efficiency overcome the shortcomings of liposomes and polymers applied separately, and have great potential for gene drug delivery.


Asunto(s)
Ciclodextrinas , Nanopartículas , Cationes , Lípidos , Liposomas/metabolismo , Polímeros , Transfección
4.
Drug Dev Ind Pharm ; 46(11): 1862-1872, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32924641

RESUMEN

Multi-drug resistance (MDR) is one of the major challenges in the successful chemotherapy of non-small cell lung cancer (NSCLC). Although RNA interference (RNAi) has been widely used to silence resistance-related genes, the effect remains unsatisfactory. In this study, we attempted to overcome MDR of NSCLC by simultaneously interfering with two RNAs that have different functions. A new pH-triggered polyglutamate brush polymer dimethylmaleic anhydride-poly(ethyleneglycol) monomethyl ether-b-polyglutamate-g-spermine (DMA-mPEG-b-PG-g-spermine, DPPGS) was designed and synthesized. The DPPGS/small interfering RNA (siRNA) complex nanoparticles (DPPGSN) were prepared. The results demonstrated that DPPGSN could be transformed from a negatively charged form into a positively charged form in the slightly acidic tumor extracellular environment. The siRNA targeting MDR1 mRNA (siMDR1) and siRNA targeting survivin mRNA (siSurvivin) could be efficiently co-delivered by DPPGS to simultaneously interfere with two genes (p < 0.01). Furthermore, DPPGS co-delivery of siMDR1 and siSurvivin lowered the IC50 value of cisplatin (DDP) in A549/DDP (p < 0.01) cells and increased the apoptosis rate of the cells (p < 0.01). Therefore, co-delivery of siMDR1 and siSurvivin using DPPGS would be a promising approach for overcoming MDR of NSCLC.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares , ARN Interferente Pequeño/uso terapéutico , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Ácido Poliglutámico/uso terapéutico , Survivin/genética , Survivin/uso terapéutico
5.
J Nanosci Nanotechnol ; 18(10): 6942-6948, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29954514

RESUMEN

In this study, magnetic CoFe2O4 nanoparticles were synthesized by hydrothermal method by using ferric nitrate and cobalt nitrate as raw materials. Subsequently, physicochemical properties of the resulting CoFe2O4 nanoparticles were systematically studied by scanning electron microscope, X-ray diffraction, N2 adsorption/desorption, Fourier transformation infrared spectroscopy and Vibration sample magnetometer measurement. Results indicated that CoFe2O4 nanoparticles with cubic spinel structure possessed an average diameter of 6.9 nm, specific surface area of 103.48 m2 · g-1, saturation magnetization of 54.65 A · m2(emu · g-1) and coercivity of 1.76×104 A · m-1. Furthermore, scavenging experiments revealed that sulfate radicals (.SO-4) was the main active species derived from persulfates, in which 72.3% of diclofenac could be degraded within 30 min treatment. This study provides a promising strategy to synthesize versatile catalyst which would be potentially applied in pharmaceutical wastewater purification.

6.
Cancer Immunol Immunother ; 66(4): 537-548, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28184969

RESUMEN

The capacity of natural killer (NK) cells to kill tumor cells without specific antigen recognition provides an advantage over T cells and makes them potential effectors for tumor immunotherapy. However, the efficacy of NK cell adoptive therapy can be limited by the immunosuppressive tumor microenvironment. Transforming growth factor-ß (TGF-ß) is a potent immunosuppressive cytokine that can suppress NK cell function. To convert the suppressive signal induced by TGF-ß to an activating signal, we genetically modified NK-92 cells to express a chimeric receptor with TGF-ß type II receptor extracellular and transmembrane domains and the intracellular domain of NK cell-activating receptor NKG2D (TN chimeric receptor). NK-92 cells expressing TN receptors were resistant to TGF-ß-induced suppressive signaling and did not down-regulate NKG2D. These modified NK-92 cells had higher killing capacity and interferon γ (IFN-γ) production against tumor cells compared with the control cells and their cytotoxicity could be further enhanced by TGF-ß. More interestingly, the NK-92 cells expressing TN receptors were better chemo-attracted to the tumor cells expressing TGF-ß. The presence of these modified NK-92 cells significantly inhibited the differentiation of human naïve CD4+ T cells to regulatory T cells. NK-92-TN cells could also inhibit tumor growth in vivo in a hepatocellular carcinoma xenograft tumor model. Therefore, TN chimeric receptors can be a novel strategy to augment anti-tumor efficacy in NK cell adoptive therapy.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Carcinoma Hepatocelular/terapia , Inmunoterapia Adoptiva/métodos , Células Asesinas Naturales/inmunología , Neoplasias Hepáticas/terapia , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Linfocitos T Reguladores/inmunología , Animales , Carcinoma Hepatocelular/inmunología , Diferenciación Celular , Procesos de Crecimiento Celular , Línea Celular Tumoral , Movimiento Celular , Citotoxicidad Inmunológica , Humanos , Interferón gamma/metabolismo , Células Asesinas Naturales/trasplante , Neoplasias Hepáticas/inmunología , Ratones , Ratones Desnudos , Subfamilia K de Receptores Similares a Lectina de Células NK/genética , Neoplasias Experimentales , Proteínas Serina-Treonina Quinasas/genética , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/genética , Proteínas Recombinantes de Fusión/genética , Factor de Crecimiento Transformador beta/metabolismo , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
7.
J Hazard Mater ; 469: 134029, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38492403

RESUMEN

A novel "ferrate/percarbonate (Fe(VI)/SPC) co-oxidation process" was used to treat ciprofloxacin (CIP) and various micropollutants (MPs), which owned better performance than mixture of Fe(VI), Na2CO3 and H2O2. The mechanism investigation found that the low-concentration H2O2 (1-2 µM) released by SPC can promote the high-valent iron intermediates (Fe(IV)/Fe(V)) of Fe(VI) to the MP oxidation, and Fe(VI) products can also activate SPC to produce hydroxyl radical (·OH). The interactive activation of Fe(VI) and SPC was realized, which retained the high selectivity of Fe(VI) to electron-rich pollutants, and also made up the oxidation of electron-deficient pollutants through •OH, improving the degradation effect of various MPs by 20-30%, and the rate constant was increased by 1 to 3 times. Moreover, non-purgeable organic carbon (NPOC) determination confirmed that â€¢OH participation reduced the NPOC value of CIP from 5.43 mg/L to 4.37 mg/L. The transformation pathway of CIP showed that Fe(VI)/SPC resulted in more hydroxylation intermediates of CIP than Fe(VI) alone. Acute toxicity assays found that the photoinhibition rate of CIP treated with Fe(VI) alone was 14.5%, while the sample treated with Fe(VI)/SPC showed no significant photoinhibition effect, which proved that the new process had good detoxification properties for CIP.

8.
Nat Prod Res ; 37(15): 2602-2607, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35337222

RESUMEN

Response surfaces methodology was established in order to optimize ultrasound-assisted aqueous alkaline protease extraction parameters of Pinus koraiensis nuts oil (PNO) in this short communication. On the oil yield, the impacts of single factors were studied. The solid-liquid ratio, enzyme concentration, enzyme hydrolysis temperature, and enzyme hydrolysis duration were chosen for further optimization of the extraction process utilizing a Box-Behnken design based on statistical significance analysis. Under ideal extraction conditions, a maximum oil recovery of 68.35% was achieved: solid-liquid ratio, enzyme concentration, enzyme hydrolysis temperature, and enzyme hydrolysis duration were 1:5 (g/mL), 3.23 mg/g, 44 °C, and 2.84 h, respectively. Furthermore, physicochemical properties testing revealed that the oil was of higher quality than other approaches. Meanwhile, the DPPH radical-scavenging activities increased with increased content compared to olive oil, with an IC50 value of 0.082 mg/mL. The method has a lot of potential when it comes to extracting oils from plants.


Asunto(s)
Nueces , Pinus , Nueces/química , Aceites de Plantas/química , Pinus/química , Agua/química , Antioxidantes/química
9.
Water Res ; 229: 119489, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36528926

RESUMEN

Peroxymonosulfate (PMS)-based photocatalysis is a promising alternative approach for wastewater disinfection. Singlet oxygen (1O2) is sensitive and efficient for bacterial inactivation. This study developed a 1O2-predominated PMS disinfection technique under visible light with CuS quantum dots (QDs) modified MIL-101(Fe) (CSQDs@MF). CuS QDs modification greatly enhanced the 1O2 quantum yield by 80% than that of MIL-101(Fe). Photoelectricity and photoluminescence tests demonstrated that both the enhanced electron transfer and energy transfer were responsible for improved 1O2 generation in Vis/PMS/CSQDs@MF system. The system took 60 min to inactivate 7.5-log E. coli, and it could be applied in a broad pH and dissolve oxygen range. Bacterial inactivation mechanism suggested that 1O2 attacked cell membrane first, then induced oxidative stress, up-regulated intracellular ROS level, eventually broke DNA strand. The system showed good disinfection performance on Gram-positive B. subtilis and fecal coliforms in practical wastewater, implying it is a promising alternative disinfection technology for wastewater treatment.


Asunto(s)
Puntos Cuánticos , Aguas Residuales , Desinfección , Escherichia coli , Electrones , Peróxidos , Oxígeno
10.
Biomaterials ; 299: 122141, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37167893

RESUMEN

Diabetic foot ulcers (DFUs) are a severe and rapidly growing diabetic complication, but treating DFUs remains a challenge for the existing therapies are expensive and highly non-responsive. Recently, we discovered that a natural adhesive from snail mucus can promote skin wound healing. Herein, inspired by the finding, we developed a double-network hydrogel biomaterial that composed of snail glycosaminoglycan (AFG) and methacrylated gelatin (GelMA), in which AFG is the main bioactive component of snail mucus and GelMA provides a scaffold mimicking the proteins in snail mucus. The biomimetic hydrogel exhibited strong tissue adhesion, potent anti-inflammatory activity, and excellent biocompatibility. The biodegradable AFG/GelMA hydrogel markedly promoted chronic wound healing in both STZ-induced type 1 diabetic rat and db/db mouse models after a single treatment. Further mechanistic research showed that the hydrogel significantly attenuated inflammation by sequestrating pro-inflammatory cytokines, as well as downregulated their expression by inhibiting NF-ĸB signaling pathway, and it can also promote macrophage polarization to M2 phenotype. Taken together, the bioinspired hydrogel can effectively promote the transition of chronic wounds from inflammation to proliferation stage. These data suggest that the AFG/GelMA hydrogel is a promising therapeutic biomaterial for the treatment of chronic diabetic wounds.


Asunto(s)
Diabetes Mellitus , Hidrogeles , Ratones , Ratas , Animales , Hidrogeles/farmacología , Gelatina/farmacología , Cicatrización de Heridas , Materiales Biocompatibles/farmacología , Diabetes Mellitus/metabolismo , Citocinas/metabolismo , Macrófagos/metabolismo
11.
Langmuir ; 28(4): 2056-65, 2012 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-22188099

RESUMEN

pH and reduction dual-bioresponsive nanosized polymersomes based on poly(ethylene glycol)-SS-poly(2-(diethyl amino)ethyl methacrylate) (PEG-SS-PDEA) diblock copolymers were developed for efficient encapsulation and triggered intracellular release of proteins. PEG-SS-PDEA copolymers with PDEA-block molecular weights ranging from 4.7, 6.8, to 9.2 kg/mol were synthesized in a controlled manner via reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(diethyl amino)ethyl methacrylate (DEAEMA) using PEG-SS-CPADN (CPADN = 4-cyanopentanoic acid dithionaphthalenoate; M(n) PEG = 1.9 kg/mol) as a macro-RAFT agent. These copolymers existed as unimers in water at mildly acidic pH (<7.2) conditions, but readily formed monodisperse nanosized polymersomes (54.5-66.8 nm) when adjusting solution pH to 7.4. These polymersomes were highly sensitive to intracellular pH and reductive environments, which resulted in fast dissociation and aggregation of polymersomes, respectively. Notably, both fluorescein isothiocyanate (FITC)-labeled bovine serum albumin (FITC-BSA) and cytochrome C (FITC-CC) proteins could facilely be encapsulated into polymersomes with excellent protein-loading efficiencies, likely as a result of electrostatic interactions between proteins and PDEA. The in vitro release studies showed that protein release was minimal (<20% in 8 h) at pH 7.4 and 37 °C. The release of proteins was significantly enhanced at pH 6.0 due to collapse of polymersomes. Notably, the fastest protein release was observed under intracellular-mimicking reductive environments (10 mM dithiothreitol, pH 7.4). MTT assays in RAW 264.7 and MCF-7 cells indicated that PEG-SS-PDEA (9.2 k) polymersomes had low cytotoxicity up to a polymer concentration of 300 µg/mL. Confocal laser scanning microscope (CLSM) observations revealed that FITC-CC-loaded PEG-SS-PDEA (9.2 k) polymersomes efficiently delivered and released proteins into MCF-7 cells following 6 h of incubation. Importantly, flow cytometry assays showed that CC-loaded PEG-SS-PDEA (9.2 k) polymersomes induced markedly enhanced apoptosis of MCF-7 cells as compared to free CC and CC-loaded PEG-PDEA (8.9 k) polymersomes (reduction-insensitive control). These dual-bioresponsive polymersomes have appeared to be highly promising for intracellular delivery of protein drugs.


Asunto(s)
Citocromos c/metabolismo , Portadores de Fármacos/química , Espacio Intracelular/metabolismo , Metacrilatos/química , Nylons/química , Polietilenglicoles/química , Albúmina Sérica Bovina/metabolismo , Succinimidas/química , Animales , Apoptosis/efectos de los fármacos , Tampones (Química) , Bovinos , Línea Celular Tumoral , Citocromos c/química , Citoplasma/metabolismo , Portadores de Fármacos/toxicidad , Humanos , Concentración de Iones de Hidrógeno , Ratones , Albúmina Sérica Bovina/química
12.
J Diabetes Complications ; 36(6): 108159, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35210136

RESUMEN

BACKGROUND: Increasing evidence has shown that fatty acid synthase (Fasn) is associated with diabetes mellitus (DM) and insulin resistance, however, it remains unclear how Fasn upregulation leads to dysregulation of energy homeostasis in islet cells. Consequently, uncovering the function of Fasn in islet cells. Consequently, uncovering the function of FASN in islet cells is immensely important for finding a treatment target. AIM: In this study, we elucidated the biological function of Fasn on the target genes in a rat insulinoma INS-1 cell line. METHODS: We created a Fasn overexpressing rat insulinoma cell line (Fasn-OE), and performed bulk RNA-sequencing (RNA-seq) experiments on Fasn-OE and INS-1 (control) cells. We first identified differentially expressed genes (DEGs) using Bioconductor package edgeR, and then discovered enriched gene ontology terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using the KEGG Orthology Based Annotation System (KOBAS) 2.0 web server. Furthermore, we identified alternative splicing events (ASEs) and regulated alternative splicing events (RASEs) by applying the ABLas pipeline. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used for validation of selected differentially expressed genes (DEGs) and Fasn-regulated alternative splicing genes (RASGs). RESULTS: In this study we found that Fasn overexpression led to significant changes of gene expression profiles, including downregulations of mRNA levels of immune related genes, including Bst2, Ddit3, Isg15, Mx2, Oas1a, Oasl, and RT1-S3 in INS-1 cell line. Furthermore, Fasn positively regulated the expression of transcription factors such as Fat1 and Ncl diabetes-related genes. Importantly, Fasn overexpression to result in alternative splicing events including in a metabolism-associated ATP binding protein mRNA Abcc5. In Gene Ontology analysis, the downregulated genes in Fasn-OE cells were mainly enriched in inflammatory response and innate immune response. In Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the downregulated genes were mainly enriched in TNF signaling pathway and cytokine-mediated signaling pathways. CONCLUSIONS: Our findings showed that upregulation of Fasn may play a critical role in islet cell immunmetabolism via modifications of immune/inflammatory related genes on transcription and alternative splicing level, which provide novel insights into characterizing the function of Fasn in islet cell immunity and for the development of chemo/immune therapies.


Asunto(s)
Acido Graso Sintasa Tipo I/metabolismo , Insulinoma , Islotes Pancreáticos , Neoplasias Pancreáticas , Empalme Alternativo , Animales , Acido Graso Sintasa Tipo I/genética , Ácido Graso Sintasas/genética , Perfilación de la Expresión Génica , Humanos , Inmunidad , ARN Mensajero , Ratas
13.
Drug Deliv ; 29(1): 2414-2427, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35904177

RESUMEN

Polymersomes possess the self-assembly vesicular structure similar to liposomes. Although a variety of comparisons between polymersomes and liposomes in the aspects of physical properties, preparation and applications have been elaborated in many studies, few focus on their differences in drug encapsulation, delivery and release in vitro and in vivo. In the present work, we have provided a modified direct hydration method to encapsulate anti-cancer drug paclitaxel (PTX) into PEG-b-PCL constituted polymersomes (PTX@PS). In addition to advantages including narrow particle size distribution, high colloid stability and moderate drug-loading efficiency, we find that the loaded drug aggregate in small clusters and reside through the polymersome membrane, representing a unique core-satellite structure which might facilitate the sustained drug release. Compared with commercial liposomal PTX formulation (Lipusu®), PTX@PS exhibited superb tumor cell killing ability underlain by multiple pro-apoptotic mechanisms. Moreover, endocytic process of PTX@PS significantly inhibits drug transporter P-gp expression which could be largely activated by free drug diffusion. In glioma mice models, it has also confirmed that PTX@PS remarkably eradicate tumors, which renders polymersomes as a promising alternative to liposomes as drug carriers in clinic.


Asunto(s)
Antineoplásicos , Liposomas , Animales , Línea Celular Tumoral , Portadores de Fármacos/química , Liberación de Fármacos , Ratones , Paclitaxel/química , Polietilenglicoles/química
14.
Biomacromolecules ; 12(10): 3612-20, 2011 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-21905663

RESUMEN

Endosomal pH-activatable doxorubicin (DOX) prodrug nanogels were designed, prepared, and investigated for triggered intracellular drug release in cancer cells. DOX prodrugs with drug grafting contents of 3.9, 5.7, and 11.7 wt % (denoted as prodrugs 1, 2, and 3, respectively) were conveniently obtained by sequential treatment of poly(ethylene glycol)-b-poly(2-hydroxyethyl methacrylate-co-ethyl glycinate methacrylamide) (PEG-b-P(HEMA-co-EGMA)) copolymers with hydrazine and doxorubicin hydrochloride. Notably, prodrugs 1, 2, and 3 formed monodispersed nanogels with average sizes of 114.4, 75.3, and 66.3 nm, respectively, in phosphate buffer (PB, 10 mM, pH 7.4). The in vitro release results showed that DOX was released rapidly and nearly quantitatively from DOX prodrug nanogels at endosomal pH and 37 °C in 48 h, whereas only a minor amount (ca. 20% or less) of drug was released at pH 7.4 under otherwise the same conditions. Confocal laser scanning microscope (CLSM) observations revealed that DOX prodrug nanogels delivered and released DOX into the cytosols as well as cell nuclei of RAW 264.7 cells following 24 h incubation. MTT assays demonstrated that prodrug 3 had pronounced cytotoxic effects to tumor cells following 72 h incubation with IC(50) data determined to be 2.0 and 3.4 µg DOX equiv/mL for RAW 264.7 and MCF-7 tumor cells, respectively. The corresponding polymer carrier, PEG-b-P(HEMA-co-GMA-hydrazide), was shown to be nontoxic up to a tested concentration of 1.32 mg/mL. These endosomal pH-activatable DOX prodrug nanogels uniquely combining features of water-soluble macromolecular prodrugs and nanogels offer a promising platform for targeted cancer therapy.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/farmacología , Portadores de Fármacos/síntesis química , Terapia Molecular Dirigida/métodos , Profármacos/síntesis química , Ácidos/química , Ácidos/farmacología , Animales , Antibióticos Antineoplásicos/química , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Portadores de Fármacos/farmacología , Endocitosis , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Femenino , Humanos , Hidrazinas/química , Concentración de Iones de Hidrógeno , Macrófagos/citología , Macrófagos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Ratones , Micelas , Polietilenglicoles/química , Ácidos Polimetacrílicos/química , Profármacos/farmacología
15.
Zhonghua Gan Zang Bing Za Zhi ; 19(10): 779-81, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22409853

RESUMEN

OBJECTIVE: To observe the expression change of signal regulatory protein alpha1 (SIRPalpha1) in autoimmune hepatitis (AIH) and approach the relationship between SIRPalpha1 and the extent of inflammation. METHODS: Immunohistochemistry is used to detect the expression of SIRPalpha1 in the paraffin section preparations of 33 AIH and 10 normal hepatic tissue. RESULTS: SIRPalpha1 is positive or weakly positive expressed in AIH. The staining is localized in the cytoplasm of Kupffer cells in the hepatic sinusoid with focal distribution. It is negative in normal hepatic tissue. In light AIH, it is negative or weakly positive expressed with a 36.4 percent of the positive rate (4/11). The positive or strong positive expression is found in the moderate AIH with an 84.2 percent of the positive rate(16/19). There is statistical significance between both light AIH, moderate AIH and severe AIH (P less than 0.001) and moderate AIH and light AIH (P less than 0.001). There is no statistical significance between both light AIH and severe AIH (P = 0.145 ) and moderate AIH and severe AIH (P = 0.084). CONCLUSIONS: As a negative regulatory factor, the expression of SIRPalpha1 in hepatic sinusoid Kupffer cells is some associated with the extent of AIH.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Hepatitis Autoinmune/metabolismo , Receptores Inmunológicos/metabolismo , Adolescente , Adulto , Anciano , Comunicación Celular , Niño , Femenino , Hepatitis Autoinmune/patología , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Macrófagos del Hígado/metabolismo , Macrófagos del Hígado/patología , Masculino , Persona de Mediana Edad , Adulto Joven
16.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(9): 823-8, 2010 Sep.
Artículo en Zh | MEDLINE | ID: mdl-21092653

RESUMEN

OBJECTIVE: to explore the value of in vivo dynamic monitoring of abdominal aortic atherosclerosis (AS) by high field magnetic resonance (MR) imaging (MRI) in apoE-/- mice fed a high fat diet or infused with angiotensin. METHODS: high fat diet or angiotensin II infusion was applied to apoE-/- mice for establishment of abdominal aortic atherosclerosis model. Abdominal aorta MRI was performed at 3 time points (baseline, 3 and 6 months) in 13 high fat diet fed apoE-/- mice aged 10-12 months and 3 wild-type control mice; 10 apoE-/- mice aged 6 months were infused with angiotensin II (1000 or 500 ng × kg(-1)× min(-1), n = 5 each) or saline for 14 d through Osmotic minipump. The abdominal aortic artery MRI was performed at baseline and 14 d after infusion. Black blood sequences of FLASH T1 weighted images and Proton density weighted-T2 weighted dual echo images were obtained. At each observation time post MRI, mice (n = 3, 5 and 5 for high fat diet group and n = 5 and 5 for angiotensin II infusion group) were sacrificed for pathological examination of the abdominal artery. RESULTS: (1) the abdominal aorta atherosclerosis was identified in both high fat diet and angiotensin II treated apoE-/- mice but in WT controls. Lesion progression was documented in high fat diet fed apoE-/- mice characterized by significantly increased vessel wall (a marker of atherosclerotic burden, F = 29.94, P < 0.05) and gradually increased plaque signal in PDW and T2W images. Results derived from MRI corresponded histopathology findings in high fat diet fed apoE-/- mice (correlative coefficient = 0.84, 0.95, 0.90, P < 0.05, respectively). Both MRI and histology showed increased lipid composition and decreased fibrotic composition in these mice. (2) The vessel wall area increased significantly [(1.21 ± 0.21) mm(2) vs. (2.65 ± 0.48) mm(2), P < 0.05] and the abdominal aortic dissection aneurysms was identified in apoE-/- mice infused with high angiotensin II. The vessel wall area also increased [(0.85 ± 0.11) mm(2) vs. (1.01 ± 0.17) mm(2), P < 0.05] in low angiotensin II infused apoE-/- mice and the coefficient between MR and histopathology is 0.934. CONCLUSION: abdominal aortic unstable plaque model could be established by both high fat diet and angiotensin II infusion in apoE mice, angiotensin II infusion can transiently accelerate the progression of AS and can induce abdominal aortic dissection. Serial MR black blood sequences could demonstrate the development and progression of atherosclerosis in mouse abdominal aorta with excellent agreement to histopathology finding in terms of atherosclerotic burden and plaque composition. Thus, MRI appears to be a useful tool for in vivo AS plaque dynamic monitoring in mice.


Asunto(s)
Arteriosclerosis , Modelos Animales de Enfermedad , Imagen por Resonancia Magnética/métodos , Angiotensina II/administración & dosificación , Animales , Aorta Abdominal , Apolipoproteínas E , Dieta , Grasas de la Dieta/administración & dosificación , Masculino , Ratones , Ratones Noqueados
17.
J Hazard Mater ; 383: 121236, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-31563046

RESUMEN

Advanced oxidation methods based on photocatalysis and sulfate radicals have attached most interest towards contaminant degradation. However, there are a lack of coupling two methods in the field of pollutant degradation. In the present study, a new Bi2O3/CuNiFe LDHs composite was fabricated and it could efficiently activate persulfate (PS) for lomefloxacin (LOM) decomposition under simulated sunlight, in which 84.6% of LOM (10 mg·L-1) was degraded over 40 min with 0.4 g·L-1 of Bi2O3/CuNiFe LDHs composite and 0.74 mM of PS at natural pH. In addition, the Bi2O3/CuNiFe LDHs composite possessed good reusability and stability at least four runs. Moreover, active radical scavenging experiments indicated that hydroxyl radicals (HO·), sulfate radicals (SO4·-), superoxide radicals (O2·-) and hole (h+) were the main radicals under LOM degradation process. Subsequently, the possible degradation intermediates were determined and the decomposition pathways were put forward. At the same time, activated sludge inhibition experiments were performed to assess the variation of toxicity of LOM and its degradation intermediates during oxidation. Finally, possible reaction mechanism of Bi2O3/CuNiFe LDHs composite for PS activation under simulated sunlight was proposed.


Asunto(s)
Luz Solar , Contaminantes Químicos del Agua , Fluoroquinolonas , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
18.
Exp Ther Med ; 18(3): 2178-2186, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31410170

RESUMEN

As a strategy to prevent the well-known immunosuppressant effects of cyclophosphamide (CY), the immunomodulatory activity of the polysaccharide isolated from Urtica macrorrhiza Hand.-Mazz. (UMHMPS) was investigated in the present study. The chemical properties of UMHMPS, including total carbohydrates, uronic acid, protein contents, monosaccharide compositions, molecular weight and structural confirmation, were investigated. The immunomodulatory activity of UMHMPS was evaluated using a CY-induced immunosuppression mouse model. The results revealed that UMHMPS, which is composed of rhamnose, gluconic acid, galactose acid, galactose and xylose, exhibited potent immunomodulatory activity and low toxicity in mice. It increased the secretions of secretory immunoglobulin A, interferon (IFN)-γ and interleukin (IL)-4, and maintained the balance of the ratios of IFN-γ/IL-4 and cluster of differentiation (CD)3+/CD19+ cells in Peyer's patches. Furthermore, it increased the expression of Toll-like receptor (TLR)-4, indicating that TLR4 may be one of the receptors of UMHMPS. Therefore, the present study provides evidence for the potential use of UMHMPS as an immune enhancement drug in chemotherapy.

19.
Carbohydr Polym ; 224: 115146, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31472868

RESUMEN

Fucosylated glycosaminoglycan (FG), a glycosaminoglycan derivative containing distinct sulfated fucose (FucS) branches, displays potent anticoagulant activity by inhibiting the intrinsic tenase complex (iXase). Herein, AmFG, SvFG and HaFG from three species of sea cucumbers were isolated and depolymerized by ß-eliminative cleavage. Three series of fragments, A1-A4, S1-S4 and H1-H4, were purified from the depolymerized FGs. Based on structural analysis of these fragments, three FGs were deduced as -{→4)-[L-FucS-α(1→3)]-D-GlcA-ß(1→3)-D-GalNAc4S6S-ß(1}n-. The structures differed in sulfation types of FucS, namely, most of FucS in AmFG was Fuc3S4S, but the FucS in SvFG was Fuc2S4S, while the FucS in HaFG was Fuc3S4S, Fuc2S4S and Fuc4S. However, all FucS branches attached to C-3 of GlcA as monosaccharides. Anticoagulant and anti-iXase assays showed the octasaccharide is the minimum fragment for potent anticoagulant activity via anti-iXase irrespective of FucS types. Among FG fragments with same degree of polymerization, oligosaccharides containing Fuc2S4S had more potent anti-iXase activity.


Asunto(s)
Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/farmacología , Fucosa/química , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Anticoagulantes/química , Anticoagulantes/farmacología , Secuencia de Carbohidratos , Cisteína Endopeptidasas
20.
Biomaterials ; 183: 77-92, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30149232

RESUMEN

Many human cancer cells exhibit an oncogenetic-driven addiction to glutamine (Gln) as rapidly proliferating cancer cells consume Gln at a dramatically increased rate compared to normal cells. Tumor cells, therefore, compete with host cells for Gln, which causes Gln to flux from normal tissues to the tumor. We have developed and characterized a Gln macromolecular analog polyglutamine (PGS) for the delivery of gene regulators, such as siRNAs, in our previous works. Here, we hypothesize that PGS can utilize the Gln transporter SLC1A5 to specifically deliver therapeutic compounds to Gln-addicted cancer cells. Compared to human lung fibroblast HLF cells, cisplatin-resistant human lung adenocarcinoma A549/DDP cells significantly overexpress SLC1A5, which has a high binding affinity to PGS, as confirmed through molecular docking analysis. Due to the differences in Gln metabolism between malignant and normal cells, PGS/siRNA complexes were remarkably increased in cancer cells, especially when cells were deprived of Gln, which mirrors the conditions that are commonly found in a tumor microenvironment. Furthermore, we identified that chemical and genetic inhibition of Gln transporter SLC1A5 reduced the cellular internalization of PGS/siRNA complexes, suggesting a critical role for SLC1A5 in PGS uptake in cells. In turn, PGS upregulated SLC1A5 expression. Increased uptake of PGS complexes profoundly decreased intracellular Gln levels. Decreased Gln caused a moderate reduction in cell growth. To restore drug sensitivity and further enhance anti-tumor effects, the hybrid siRNAs anti-Survivin and anti-MDR1 (siSM), as model therapeutics, were administered through the PGS delivery system, which resulted in knockdown of Survivin and MDR1 and further sensitized cancer cells to the drug cisplatin (DDP). Since PGS complexes administered i.v. mostly accumulated in the lung parenchyma, a lung orthotopic tumor model was established to evaluate their inhibitory effects on tumors in the lungs. PGS/siSM comparably decreased the rate of tumor growth, while concurrent administration of PGS/siSM and DDP enhanced this effect and insignificantly improved life span. Consistent with our hypothesis, this study demonstrated that PGS mimicked Gln in the SLC1A5 pathway and selectively ferried therapeutics to Gln-addicted cancer cells. Our findings identified a new lung cancer targeting strategy based on Gln metabolism and can be used as a drug/gene delivery system.


Asunto(s)
Sistema de Transporte de Aminoácidos ASC/metabolismo , Portadores de Fármacos/química , Glutamina/metabolismo , Neoplasias Pulmonares/terapia , Antígenos de Histocompatibilidad Menor/metabolismo , Nanopartículas/química , Péptidos/química , ARN Interferente Pequeño/administración & dosificación , Sistema de Transporte de Aminoácidos ASC/genética , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Cisplatino/farmacología , Liberación de Fármacos , Resistencia a Antineoplásicos , Terapia Genética , Humanos , Neoplasias Pulmonares/genética , Ratones Endogámicos BALB C , Ratones Desnudos , Antígenos de Histocompatibilidad Menor/genética , ARN Interferente Pequeño/genética , Microambiente Tumoral
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