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1.
Mol Pharm ; 20(4): 2138-2149, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36877183

RESUMO

Systemic fungal infections are an increasingly prevalent health problem. Amphotericin B (AmB), a hydrophobic polyene antibiotic, remains the drug of choice for life-threatening invasive fungal infections. However, it has dose-limiting side effects, including nephrotoxicity. The efficacy and toxicity of AmB are directly related to its aggregation state. Here, we report the preparation of a series of telodendrimer (TD) nanocarriers with the freely engineered core structures for AmB encapsulation to fine-tune AmB aggregation status. The reduced aggregation status correlates well with the optimized antifungal activity, attenuated hemolytic properties, and reduced cytotoxicity to mammalian cells. The optimized TD nanocarrier for monomeric AmB encapsulation significantly increases the therapeutic index, reduces the in vivo toxicity, and enhances antifungal effects in mouse models with Candida albicans infection in comparison to two common clinical formulations, i.e., Fungizone and AmBisome.


Assuntos
Anfotericina B , Micoses , Camundongos , Animais , Anfotericina B/química , Antifúngicos/química , Composição de Medicamentos , Candida albicans , Mamíferos
2.
Macromol Rapid Commun ; 44(23): e2300322, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37533180

RESUMO

Imbalanced immune regulation leads to the abnormal wound healing process, e.g., chronic unhealing wound or hypertrophic scar formation. Thus, the attenuation of the overflowing inflammatory factors is a viable approach to maintain the homeostatic immune regulation to facilitate normal wound healing. A versatile telodendrimer (TD) nanotrap (NT) platform is developed for efficient biomolecular protein binding. The conjugation of TD NT in size-exclusive biocompatible hydrogel resin allows for topical application for cytokine scavenging. Fine-tuning the TD NT density/valency in hydrogel resin controls resin swelling, optimizes molecular diffusion, and improves cytokine capture for effective immune modulation. The hydrogel with reduced TD NT density allows for higher protein/cytokine adsorption capacity with faster kinetics, due to the reduced barrier of TD NT nano-assembly. The positively charged TD NT hydrogel exhibits superior removal of negatively charged proinflammatory cytokines from the lipopolysaccharide (LPS, a potent endotoxin) primed immune cell culture medium. The negatively charged TD NT hydrogel removes positively charged anti-inflammatory cytokines efficiently from cell culture medium. TD NT hydrogel effectively constrains the local inflammation induced by subcutaneous LPS injection in mice. These results indicate the great potential applications of the engineered TD NT hydrogel as topical immune modulatory treatments to attenuate local inflammation.


Assuntos
Hidrogéis , Lipopolissacarídeos , Animais , Camundongos , Hidrogéis/química , Lipopolissacarídeos/farmacologia , Cicatrização , Citocinas/farmacologia , Inflamação , Antibacterianos/farmacologia
3.
Bull Environ Contam Toxicol ; 111(5): 66, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37904018

RESUMO

As one of the most widely used herbicides in agricultural industry, the residues of glyphosate (GLY) are frequent environmental pollutants. Freshwater planarian Dugesia japonica has been developed as a model for neurotoxicology. In this study, the effects of GLY on locomotion and feeding behavior, as well as neuroenzyme activities and mRNA expressions of D. japonica were determined. Additionally, histochemical localization was executed to explore the damage to the central nervous system (CNS) of planarians stressed by GLY. The results showed that the locomotor velocity, ingestion rate and the neuroenzyme activity were inhibited and the gene expressions were altered. Also, histo-architecture injury to CNS of planarians upon GLY exposure in a time-dependent manner was observed. Collectively, our results indicate that GLY can cause neurotoxicity to freshwater planarians representing as reduction in locomotor velocity and feeding rate by disturbing the neurotransmission systems and damaging the structure of CNS.


Assuntos
Planárias , Animais , Planárias/genética , Glicina/toxicidade , Glicina/metabolismo , Glifosato
4.
Mol Pharm ; 18(6): 2349-2359, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33983742

RESUMO

Serum protein adsorption on the nanoparticle surface determines the biological identity of polymeric nanocarriers and critically impacts the in vivo stability following intravenous injection. Ultrahydrophilic surfaces are desired in delivery systems to reduce the serum protein corona formation, prolong drug pharmacokinetics, and improve the in vivo performance of nanotherapeutics. Zwitterionic polymers have been explored as alternative stealth materials for biomedical applications. In this study, we employed facial solid-phase peptide chemistry (SPPC) to synthesize multifunctional zwitterionic amphiphiles for application as a drug delivery vehicle. SPPC facilitates synthesis and purification of the well-defined dendritic amphiphiles, yielding high-purity and precise architecture. Zwitterionic glycerylphosphorylcholine (GPC) was selected as a surface moiety for the construction of a ultrahydrophilic dendron, which was coupled on solid phase to a hydrophobic dendron using multiple rhein (Rh) molecules as drug-binding moieties (DBMs) for doxorubicin (DOX) loading via pi-pi stacking and hydrogen bonding. The resulting zwitterionic amphiphilic Janus dendrimer (denoted as GPC8-Rh4) showed improved stabilities and sustained drug release compared to the analogue with poly(ethylene glycol) (PEG) surface (PEG5k-Rh4). In vivo studies in xenograft mouse tumor models demonstrated that the DOX-GPC8-Rh4 nanoformulation significantly improved anticancer effects compared to DOX-PEG5k-Rh4, owing to the improved in vivo pharmacokinetics and increased tumor accumulation.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Fármacos por Nanopartículas/síntese química , Técnicas de Síntese em Fase Sólida/métodos , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Dendrímeros/síntese química , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Glicerilfosforilcolina/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Ecotoxicology ; 29(3): 295-304, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32088881

RESUMO

As the top-selling herbicide in the world, glyphosate distributes widely in natural environment and its influence on the ecological security and human health has attracted more and more concern. Glutathione S-transferases (GSTs) are a well-characterized superfamily of isoenzymes for cellular defense against exogenous toxic substances and therefore protect organisms from injury. In this study, the complete cDNA sequence of GST gene (named as Dja-GST) in freshwater planarian Dugesia japonica was firstly cloned by means of RACE method. The full-length Dja-GST comprises of 706 nucleotides which encodes a polypeptide of 200 amino acids. Dja-GST has two representative GST domains at the N- and C-termini. The conservative GST-N domain includes G-site Y8, F9, R14, W39, K43, P52 and S64, while the variable GST-C domain contains H-site K104, V156, D159 and L161. Sequence analysis, phylogenetic tree reconstruction and multiple alignment collectively indicate that Dja-GST belongs to the Sigma class of GST superfamily. Also, GST gene expression profile, GST enzymatic activity and MDA content in response to glyphosate exposure were systematically investigated and the correlations among them were analyzed. The results suggest that glyphosate exposure modified the mRNA transcription and enzymatic activity of GST, as well as the MDA content in planarians, indicating that Dja-GST might play an important part in organisms defending against oxidative stress induced by glyphosate. This work lays a molecular foundation for further exploring the exact functions of Dja-GST and gives an important implication for evaluating the ecological environment effects of herbicide glyphosate.


Assuntos
Glutationa Transferase/genética , Glicina/análogos & derivados , Herbicidas/toxicidade , Planárias/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Clonagem Molecular , Água Doce , Glicina/toxicidade , Estresse Oxidativo , Glifosato
6.
Bull Environ Contam Toxicol ; 104(6): 804-808, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32372209

RESUMO

As the worldwide top-selling herbicide, glyphosate is ubiquitously distributed in the natural environment, and its influence on the ecological safety and human health has being increasingly concerned. In this study, mRNA expressions of GPX and three heat shock protein genes in freshwater planarian Dugesia japonica in response to glyphosate were determined, and two oxidative stress parameters were measured. The results suggested that GPX activity can be used as a more sensitive biomarker in contrast with GPX gene expression, and mRNA expressions of Hsp70, Hsp90 genes are more sensitive than Hsp40 for planarians in response to glyphosate stress. Besides, the deduced T-AOC as well as varied GPX activity and mRNA expression levels of Hsps also indicated that glyphosate exposure would inhibit antioxidation and induce oxidative stress in D. japonica, while specific antioxidant systems and stress proteins tried to protect cells by their own regulation. The results of this study will be helpful to elucidate the stress response mechanisms of freshwater planarians to herbicide glyphosate.


Assuntos
Expressão Gênica/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Planárias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Glicina/toxicidade , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Estresse Oxidativo/genética , Planárias/genética , Planárias/metabolismo , Glifosato
7.
Ecotoxicol Environ Saf ; 165: 88-95, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30193168

RESUMO

Catalase (CAT) is an important antioxidant enzyme that protects aerobic organisms against oxidative damage by degrading hydrogen peroxide to oxygen and water. CAT mRNAs have been cloned from many species and employed as useful biomarkers of oxidative stress. In the present study, we cloned the cDNA sequence of CAT gene from freshwater planarian Dugesia japonica (designated as DjCAT) by means of RACE method. Sequence analysis and multiple alignment jointly showed that the full-length cDNA sequence consists of 1734 nucleotides, encoding 506 amino acids. Three catalytic amino acid residues of His71, Asn144 and Tyr354, two CAT family signature sequences of a proximal active site signature (60FDRERIPERVVHAKGGGA77) and a heme-ligand signature motif (350RLFSYRDTQ358) are highly conserved, suggesting that the DjCAT belongs to the NADPH and heme-binding CAT family and has similar functions. In addition, the transcriptional level of CAT gene and activity of CAT enzyme upon acute exposure of environmental pollutants glyphosate and 1-decyl-3-methylimidazolium bromide ([C10mim]Br) were investigated systematically. The variation of CAT mRNA expression in D. japonica was quantified by real-time PCR and the results indicated that it was up-regulated after exposure to glyphosate or [C10mim]Br with a dose-dependent manner but not linearly. Even though the variation trend of CAT activity upon glyphosate stress was not monotonously increased and inconsistent with that after [C10mim]Br exposure on day 1 and 3 sampling time, with the duration prolonged to day 5 they both presented a dose-dependent increase and the differences achieved extreme significance in all treated groups compared to the control. These findings suggested that DjCAT plays an important role in antioxidant defense in D. japonica, and the mRNA expression of CAT would also be used as an effective biomarker to monitor the pollution in aquatic environment just like its corresponding enzyme.


Assuntos
Catalase/genética , Catalase/metabolismo , DNA Complementar/metabolismo , Poluentes Ambientais/farmacologia , Expressão Gênica/efeitos dos fármacos , Planárias/enzimologia , Sequência de Aminoácidos , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Brometos/farmacologia , Clonagem Molecular , Relação Dose-Resposta a Droga , Glicina/análogos & derivados , Glicina/farmacologia , Herbicidas/farmacologia , Imidazóis/farmacologia , Oxirredução , Estresse Oxidativo , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Regulação para Cima/efeitos dos fármacos , Glifosato
8.
Bull Environ Contam Toxicol ; 98(4): 484-488, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28210751

RESUMO

The aim of this study was to evaluate the genotoxic potential of an urban river - the Wei River in Xinxiang, China using randomly amplified polymorphic DNA (RAPD) assay in planarians. The results showed that the total number of polymorphic bands and varied bands in RAPD patterns of treated planarians decreased with the water sample site far away from the sewage outlet of a factory. In addition, the genome template stability of treated groups decreased and the degree of the decline was negatively related to the distance between the sample site and the sewage outlet, suggesting that the Wei River water had genotoxicity effects on planarians and strengthening the management of the Wei River was necessary. Furthermore, this work also indicated that RAPD assay in planarians was a very promising test for environmental monitoring studies.


Assuntos
Dano ao DNA , Planárias/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Rios/química , Poluição da Água/efeitos adversos , Animais , China , Monitoramento Ambiental/métodos
9.
Small ; 12(31): 4185-92, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27375237

RESUMO

A strategy to precisely engineer lipidoid-telodendrimer binary hybrid nanoparticles that offer enhanced cell membrane permeability for therapeutic proteins to reach the intracellular targets is established. The highly controllable biochemical and physical properties of the nanoparticles make them promising for protein-based brain cancer treatment with the assistance of convection-enhanced delivery.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Lipídeos/química , Nanopartículas/química , Proteínas/administração & dosagem , Proteínas/química , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Humanos , Modelos Teóricos , Proteínas/uso terapêutico
10.
Ecotoxicol Environ Saf ; 134P1: 17-22, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27573364

RESUMO

The randomly amplified polymorphic DNA (RAPD) assay has been used to detect DNA alternation and mutation recently. However, the effectiveness of this method in detecting DNA damage in planarians, a model organism for assessing the toxicity of environmental pollutants is unknown. In the present study, RAPD assay was used to detect the DNA damage in planarians treated by the ionic liquid 1-octyl-3-methylimidazolium bromide ([C8mim]Br) for the first time. Among the 20 test RAPD primers, 13 primers with 60-70% GC content produced unique polymorphic band profiles. A total of 60 bands were observed in the untreated control planarians. In comparison with the control group, the [C8mim]Br-treated groups displayed differences in RAPD patterns in the band intensity, disappearance of normal bands and appearance of new bands. The variation of RAPD profiles showed both concentration- and time-effect relationships. Meanwhile, the genomic template stability (GTS) of treated planarians decreased and exhibited negative correlation to the exposure concentration and time of [C8mim]Br. Our results suggested that [C8mim]Br had genotoxic effects on planarians, and this DNA damage analysis would lay the foundation for further elucidating the toxicity mechanisms of ionic liquids on planarians. Furthermore, RAPD analysis was proved to be a highly sensitive method for the detection of DNA damage induced by environmental pollutants like toxic chemicals on planarians.

11.
Toxicol Ind Health ; 32(9): 1675-83, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25812565

RESUMO

The activities of antioxidant enzymes and the levels of glutathione (GSH) and malondialdehyde (MDA) were determined when freshwater planarian Dugesia japonica was exposed to different concentrations of 1-octyl-3-methylimidazolium bromide ([C8mim]Br) for one, three, and five days. The results showed that superoxide dismutase (SOD) activity began to increase in all treated groups after three days of exposure, while catalase (CAT) activity was inhibited after the first day, but increased notably on the fifth day except for the lowest concentration group. The activity of glutathione peroxidase (GPX) was induced from the first day of exposure and increased significantly after five days in all treated groups. During the experiment, the levels of intracellular GSH in all treated groups were higher than that of the control group. Changes in MDA suggest that [C8mim]Br is toxic to D japonica and may result in lipid peroxidation in planarian. Our results also indicate that GPX as well as GSH seem to be more sensitive biomarkers of oxidative stress compared with SOD and CAT.


Assuntos
Brometos/toxicidade , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Planárias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/antagonistas & inibidores , Catalase/metabolismo , China , Glutationa/metabolismo , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Proteínas de Helminto/agonistas , Proteínas de Helminto/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Concentração Osmolar , Planárias/isolamento & purificação , Planárias/metabolismo , Rios , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Fatores de Tempo
12.
Mol Pharm ; 12(4): 1216-29, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25692376

RESUMO

Certain natural products such as gambogic acid (GA) exhibit potent antitumor effects. Unfortunately, administration of these natural products is limited by their poor solubility in conventional pharmaceutical solvents. In this study, a series of telodendrimers, composed of linear polyethylene glycol (PEG)-blocking-dendritic oligomer of cholic acid (CA) and vitamin E (VE), have been designed with architectures optimized for efficient delivery of GA and other natural anticancer compounds. Two of the telodendrimers with segregated CA and VE domains self-assembled into stable cylindrical and/or spherical nanoparticles (NPs) after being loaded with GA as observed under transmission electron microscopy (TEM), which correlated with the dynamic light scattering (DLS) analysis of sub-30 nm particle sizes. A very high GA loading capacity (3:10 drug/polymer w/w) and sustained drug release were achieved with the optimized telodendrimers. These novel nanoformulations of GA were found to exhibit similar in vitro cytotoxic activity against colon cancer cells as the free drug. Near-infrared fluorescence small animal imaging revealed preferential accumulation of GA-loaded NPs into tumor tissue. The optimized nanoformulation of GA achieved superior antitumor efficacy compared to GA-Cremophor EL formulation at equivalent doses in HT-29 human colon cancer xenograft mouse models. Given the mild adverse effects associated with this natural compound and the enhanced anticancer effects via tumor targeted telodendrimer delivery, the optimized GA nanoformulation is a promising alternative to the traditional chemotherapy in colon cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Dendrímeros/química , Vitamina E/química , Xantonas/administração & dosagem , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Feminino , Células HCT116 , Hemólise , Humanos , Luz , Células MCF-7 , Camundongos , Camundongos Nus , Micelas , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Transplante de Neoplasias , Polietilenoglicóis/química , Espalhamento de Radiação , Solubilidade
13.
BMC Gastroenterol ; 15: 65, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-26054761

RESUMO

BACKGROUND: Ascites is the most common complication of cirrhosis. It may lead to the consequence of poor prognosis and the deterioration of quality of life. Asopressin V2 receptor antagonists is a kind of vaptans, and it has been proved to be effective in hyponatremia patients. We conducted a meta-analysis about treatment of vaptans in cirrhosis patients with ascites. METHODS: Following our selection criteria, we collected a total of 14 studies containing 16 randomized controlled trials (2620 patients) from a series of database about the treatment with vaptans for cirrhosis with ascites patients. The included studies compared the treatment effect of lixivaptan (VPA 985), or RMJ-351647, or satavaptan, or tolvaptan with placebo. RESULTS: The included vaptans (asopressin V2 receptor antagonists) showed significant effect of increasing the serum sodium concentration for cirrhosis patients (WMD = 2.11 mmol/L, p < 0.00001). Patients also could acquire significant improvement of ascites, as this kind of aquaretics can significantly reduce ascites patients' weight (WMD = -1.53, p < 0.00001), abdominal girth (WMD = -2.04, p < 0.00001), and the ratio of worsening ascites (RR = 0.51, p = 0.001). Though the drug did not produce more total adverse events (RR = 1.04, p = 0.09) and the total serious events (RR = 1.04, p = 0.42), the emergence of excessive correction of serum sodium concentrations (>145 mmol/L) was more frequently noted in patients under the employment of vaptans (RR = 2.14, 95 % CI [1.45, 3.16], p = 0.0001). Whether with the administration of vaptans for short-term or long-term, no survival benefit was detected from the selected studies. CONCLUSIONS: Asopressin V2 receptor antagonists could play an effective and safe role in symptomatic treatment for cirrhosis patients with ascites, especially for refractory ascites patients who presented insufficient response to conventional diuretics.


Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos/uso terapêutico , Ascite/tratamento farmacológico , Cirrose Hepática/complicações , Ascite/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
14.
Langmuir ; 30(23): 6878-88, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24849780

RESUMO

A series of telodendrimer (a linear polyethyelene glycol-block-dendritic oligo-cholic acid) have been synthesized via a bottom-up approach to optimize the hemocompatibility of the nanocarrier. Numbers of hydrophilic glycerol groups were introduced onto the polar surface of cholic acid to reduce the plasma membrane lytic activity of telodendrimers. An interesting result was observed: only an optimum number of glycerol introduced could reduce the hemolytic properties of the nanocarrier; on the contrary, more glycerols or the amino-glycerol substitution onto cholic acid significantly increased the hemolytic properties of the nanocarriers. To further elucidate the structure-property relationship, the molecular dynamic approach was used to simulate the conformation of the subunits of telodendrimers with different glycerol substitution, and the binding energies and the polar surface areas of the hairpin conformations were calculated to explain the membrane activities of nanocarriers. In addition, these telodendrimer subunits were synthesized and their membrane activities were tested directly, which validated the computational prediction and correlated with the observed hemolytic activity of nanocarriers. The glycerol substitution sustained the facial amphiphilicity of cholic acid, maintaining the superior drug loading capacity (paclitaxel and doxorubicin), stability, cell uptake, and anticancer efficacy of payloads. The in vivo optical imaging study indicated that the optimized nanocarriers can specifically deliver drug molecules to the tumor sites more efficiently than free drug administration, which is essential for the enhanced cancer treatment.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Polímeros/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Portadores de Fármacos/efeitos adversos , Sistemas de Liberação de Medicamentos/efeitos adversos , Feminino , Células HT29 , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Micelas , Simulação de Dinâmica Molecular , Paclitaxel/administração & dosagem , Paclitaxel/química , Paclitaxel/uso terapêutico , Polímeros/efeitos adversos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Biomacromolecules ; 15(5): 1837-44, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24725005

RESUMO

A series of block and random copolymers consisting of oligo(ethylene glycol) and cholic acid pendant groups were synthesized via ring-opening metathesis polymerization of their norbornene derivatives. These block and random copolymers were designed to have similar molecular weights and comonomer ratios; both types of copolymers showed thermosensitivity in aqueous solutions with similar cloud points. The copolymers self-assembled into micelles in water as shown by dynamic light scattering and transmission electron microscopy. The hydrodynamic diameter of the micelles formed by the block copolymer is much larger and exhibited a broad and gradual shrinkage from 20 to 54 °C below its cloud point, while the micelles formed by the random copolymers are smaller in size but exhibited some swelling in the same temperature range. Based on in vitro drug release studies, 78% and 24% paclitaxel (PTX) were released in 24 h from micelles self-assembled by the block and random copolymers, respectively. PTX-loaded micelles formed by the block and random copolymers exhibited apparent antitumor efficacy toward the ovarian cancer cells with a particularly low half-maximal inhibitory concentration (IC50) of 27.4 and 40.2 ng/mL, respectively. Cholic acid-based micelles show promise as a versatile and potent platform for cancer chemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Ácido Cólico/química , Portadores de Fármacos/química , Etilenoglicol/química , Paclitaxel/administração & dosagem , Polímeros/química , Temperatura , Antineoplásicos/química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Hidrodinâmica , Concentração Inibidora 50 , Micelas , Modelos Moleculares , Estrutura Molecular , Neoplasias Ovarianas/patologia , Paclitaxel/química , Paclitaxel/farmacologia , Tamanho da Partícula , Polímeros/administração & dosagem , Polímeros/síntese química , Propriedades de Superfície , Células Tumorais Cultivadas
16.
Acta Biomater ; 178: 147-159, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38447811

RESUMO

Wound infection commonly causes delayed healing, especially in the setting of chronic wounds. Local release of antibiotics is considered a viable approach to treat chronic wounds. We have developed a versatile telodendrimer (TD) platform for efficient loading of charged antibiotic molecules via a combination of multivalent and synergistic charge and hydrophobic interactions. The conjugation of TD in biocompatible hydrogel allows for topical application to provide sustained antibiotic release. Notably, a drug loading capacity as high as 20 % of the drug-to-resin dry weight ratio can be achieved. The payload content (PC) and release profile of the various antibiotics can be optimized by fine-tuning TD density and valency in hydrogel based on the charge and hydrophobic features of the drug, e.g., polymyxin B (PMB), gentamycin (GM), and daptomycin (Dap), for effective infection control. We have shown that hydrogel with moderately reduced TD density demonstrates a more favorable release profile than hydrogel with higher TD density. Antibiotics loaded in TD hydrogel have comparable antimicrobial potency and reduced cytotoxicity compared to the free antibiotics due to a prolonged, controlled drug release profile. In a mouse model of skin and soft tissue infection, the subcutaneous administration of PMB-loaded TD hydrogel effectively eliminated the bacterial burden. Overall, these results suggest that engineerable TD hydrogels have great potential as a topical treatment to control infection for wound healing. STATEMENT OF SIGNIFICANCE: Wound infection causes a significant delay in the wound healing process, which results in a significant financial and resource burden to the healthcare system. PEGA-telodendrimer (TD) resin hydrogel is an innovative and versatile platform that can be fine-tuned to efficiently encapsulate different antibiotics by altering charged and hydrophobic structural moieties. Additionally, this platform is advantageous as the TD density in the resin can also be fine-tuned to provide the desired antibiotic payload release profile. Sustained antibiotics release through optimization of TD density provides a prolonged therapeutic window and reduces burst release-induced cytotoxicity compared to conventional antibiotics application. Studies in a preclinical mouse model of bacteria-induced skin and soft tissue infection demonstrated promising therapeutic efficacy as evidenced by effective infection control and prolonged antibacterial efficacy of antibiotics-loaded PEGA-TD resin. In conclusion, the PEGA-TD resin platform provides a highly customizable approach for effective antibiotics release with significant potential for topical application to treat various bacterial wound infections to promote wound healing.


Assuntos
Resinas Acrílicas , Polietilenoglicóis , Infecções dos Tecidos Moles , Infecção dos Ferimentos , Camundongos , Animais , Antibacterianos/uso terapêutico , Hidrogéis/química , Infecções dos Tecidos Moles/tratamento farmacológico , Infecção dos Ferimentos/tratamento farmacológico , Controle de Infecções
17.
J Control Release ; 370: 626-642, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734314

RESUMO

Severe nephrotoxicity and infusion-related side effects pose significant obstacles to the clinical application of Amphotericin B (AmB) in life-threatening systemic fungal infections. In pursuit of a cost-effective and safe formulation, we have introduced multiple phenylboronic acid (PBA) moieties onto a linear dendritic telodendrimer (TD) scaffold, enabling effective AmB conjugation via boronate chemistry through a rapid, high yield, catalysis-free and dialysis-free "Click" drug loading process. Optimized AmB-TD prodrugs self-assemble into monodispersed micelles characterized by small particle sizes and neutral surface charges. AmB prodrugs sustain drug release in circulation, which is accelerated in response to the acidic pH and Reactive Oxygen Species (ROS) in the infection and inflammation. Prodrugs mitigate the AmB aggregation status, reduce cytotoxicity and hemolytic activity compared to Fungizone®, and demonstrate superior antifungal activity to AmBisome®. AmB-PEG5kBA4 has a comparable maximum tolerated dose (MTD) to AmBisome®, while over 20-fold increase than Fungizone®. A single dose of AmB-PEG5kBA4 demonstrates superior efficacy to Fungizone® and AmBisome® in treating systemic fungal infections in both immunocompetent and immunocompromised mice.


Assuntos
Anfotericina B , Antifúngicos , Fungemia , Pró-Fármacos , Animais , Anfotericina B/administração & dosagem , Anfotericina B/farmacologia , Anfotericina B/química , Anfotericina B/farmacocinética , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/uso terapêutico , Humanos , Fungemia/tratamento farmacológico , Nanopartículas/química , Liberação Controlada de Fármacos , Micelas , Camundongos , Feminino , Química Click , Candida albicans/efeitos dos fármacos , Polietilenoglicóis/química , Polietilenoglicóis/administração & dosagem
18.
Aquat Toxicol ; 256: 106425, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36805197

RESUMO

Glyphosate (GLY) is one of the most widely used agrochemicals in the world, and its exposure has become a public health concern. The freshwater planarian is an ideal test organism for detecting the toxicity of pollutants and has been an emerging animal model in toxicological studies. Nevertheless, the underlying toxicity mechanism of GLY to planarians has not been thoroughly explored. To elucidate the toxicity effects and molecular mechanism involved in GLY exposure of planarians, we studied the acute toxicity, histological change, and transcriptional response of Dugesia japonica subjected to GLY. Significant morphological malformations and histopathological changes were observed in planarians after GLY exposure for different times. Also, a number of differentially expressed genes (DEGs) were obtained at 1, 3 and 5 d after exposure; Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of these DEGs were performed, and a global and dynamic view was obtained in planarians upon GLY exposure at the transcriptomic level. Furthermore, real-time quantitative PCR (qRT-PCR) was conducted on nine DEGs associated with detoxification, apoptosis, stress response, DNA repair, etc. The expression patterns were well consistent with the RNA sequencing (RNA-seq) results at different time points, which confirmed the reliability and accuracy of the transcriptome data. Collectively, our results established that GLY could pose adverse effects on the morphology and histo-architecture of D. japonica, and the planarians are capable of responding to the disadvantageous stress by dysregulating the related genes and pathways concerning immune response, detoxification, energy metabolism, DNA damage repair, etc. To the best of our knowledge, this is the first report of transcriptomic analyses of freshwater planarians exposed to environmental pollutants, and it provided detailed sequencing data deriving from transcriptome profiling to deepen our understanding the molecular toxicity mechanism of GLY to planarians.


Assuntos
Poluentes Ambientais , Herbicidas , Planárias , Poluentes Químicos da Água , Animais , Planárias/genética , Herbicidas/toxicidade , Herbicidas/análise , Reprodutibilidade dos Testes , Poluentes Químicos da Água/toxicidade , Poluentes Ambientais/farmacologia , Glifosato
19.
Shock ; 59(6): 922-929, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36939682

RESUMO

ABSTRACT: Background: The kidney is the most common extrapulmonary organ injured in sepsis. The current study examines the ability of aerosolized nanochemically modified tetracycline 3 (nCMT-3), a pleiotropic anti-inflammatory agent, to attenuate acute kidney injury (AKI) caused by intratracheal LPS. Methods: C57BL/6 mice received aerosolized intratracheal nCMT-3 (1 mg/kg) or saline, followed by intratracheal LPS (2.5 mg/kg) to induce acute lung injury-induced AKI. Tissues were harvested at 24 h. The effects of nCMT-3 and LPS on AKI were assessed by plasma/tissue levels of serum urea nitrogen, creatinine, neutrophil gelatinase-associated lipocalin, kidney injury molecule 1, and renal histology. Renal matrix metalloproteinase (MMP) level/activity, cytochrome C, Bax, Bcl-2, caspase-3, p38 mitogen-activated protein kinase activation, NLRP3, and caspase-1 were also measured. Apoptotic cells in kidney were determined by TUNEL assay. Renal levels of IL-1ß and IL-6 were measured to assess inflammation. Results: Acute lung injury-induced AKI was characterized by increased plasma blood urea nitrogen, creatinine, injury biomarkers (neutrophil gelatinase-associated lipocalin, kidney injury molecule 1), and histologic evidence of renal injury. Lipopolysaccharide-treated mice demonstrated renal injury with increased levels of inflammatory cytokines (IL-1ß, IL-6), active MMP-2 and MMP-9, proapoptotic proteins (cytochrome C, Bax/Bcl-2 ratio, cleaved caspase-3), apoptotic cells, inflammasome activation (NLRP3, caspase-1), and p38 signaling. Intratracheal nCMT-3 significantly attenuated all the measured markers of renal injury, inflammation, and apoptosis. Conclusions: Pretreatment with aerosolized nCMT-3 attenuates LPS-induced AKI by inhibiting renal NLRP3 inflammasome activation, renal inflammation, and apoptosis.


Assuntos
Injúria Renal Aguda , Lesão Pulmonar Aguda , Sepse , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Caspase 3/metabolismo , Lipocalina-2 , Creatinina , Lipopolissacarídeos/farmacologia , Citocromos c/metabolismo , Interleucina-6/metabolismo , Proteína X Associada a bcl-2/metabolismo , Camundongos Endogâmicos C57BL , Injúria Renal Aguda/metabolismo , Apoptose , Caspase 1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Tetraciclinas/farmacologia , Inflamação/metabolismo , Sepse/metabolismo
20.
Adv Ther (Weinh) ; 5(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36590645

RESUMO

Sepsis is a complex, life-threatening hyperinflammatory syndrome associated with organ failure and high mortality due to lack of effective treatment options. Here we report a core-shell hydrogel nanoparticle with the core functionalized with telodendrimer (TD) nanotrap (NT) to control hyperinflammation in sepsis. The combination of multi-valent charged and hydrophobic moieties in TD enables effective binding with biomolecules in NT. The higher crosslinking in the shell structure of nanogel excludes the abundant large serum proteins and allows for size-selectivity in scavenging the medium-sized septic molecules (10-30 kDa), e.g., lipopolysaccharides (LPS, a potent endotoxin in sepsis), thus reducing cytokine production. At the same time, the core-shell TD NT nanogel captures the over-flowing proinflammatory cytokines effectively both in vitro and in vivo from biological fluids to further control hyperinflammation. Intraperitoneal injection of core-shell TD NT nanogel effectively attenuates NF-κB activation and cytokine production in LPS-induced septic mouse models. These results indicate the potential applications of the injectable TD NT core-shell nanogel to attenuate local or systemic inflammation.

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