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1.
Food Chem ; 422: 136236, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37130453

RESUMO

Milk fat globule membrane (MFGM) contains lipids, which are essential for promoting infant brain development and improving cognition. In this study, the lipid differences between human MFGM and four dietary lipid sources (cow MFGM, soybean, krill, and yolk) were compared using the UHPLC-Q-Exactive MS-based lipidomics techniques. A total of 45 lipid classes and 5048 lipid species were detected. The analysis of phospholipid classes revealed that the lipid composition of human MFGM and cow MFGM was more similar than the other dietary-derived lipids. Additionally, the human MFGM lipid species were compared with cow MFGM, soybean, krill, and yolk, and 401, 416, 494, and 444 significantly different lipids were identified, respectively. Through lipid metabolic pathway analysis, differential lipids were mainly involved in the glycerophospholipid metabolic pathway. Overall, these results will provide a rationale for the future addition of lipids to infant formula to more closely approximate human MFGM lipid profiles.


Assuntos
Glicolipídeos , Lipidômica , Animais , Feminino , Bovinos , Lactente , Humanos , Gorduras na Dieta , Fórmulas Infantis , Fosfolipídeos , Encéfalo/metabolismo , Gotículas Lipídicas/metabolismo
2.
Animals (Basel) ; 13(5)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36899787

RESUMO

Schisandra chinensis polysaccharide (SCP) is an experimental therapeutic for the treatment of intestinal injury. Selenium nanoparticle modification can improve the bioactivity of polysaccharides. In this study, SCP was firstly extracted and purified by a DEAE-52 column, then SCP-Selenium nanoparticles (SCP-Se NPs) were prepared, and the procedure was optimized. Thereafter, the obtained SCP-Se NPs were characterized by transmission electron microscope, X-ray diffraction, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. The influence of different storage environments on the stability of colloidal SCP-Se NPs was also investigated. Finally, the therapeutic effects of SCP-Se NPs on LPS-induced intestinal inflammatory injuries in mice were evaluated. Results showed that the optimized SCP-Se NPs were amorphous, uniform, spherical particles with a diameter of 121 nm, and the colloidal solution was stable at 4 °C for at least 14 d. Moreover, SCP-Se NPs could more effectively alleviate LPS-induced diarrhea, intestinal tissue injury, and tight junction destruction and decrease the elevated expression levels of TNF-α, IL-1ß, and IL-6 compared with SCP. These results demonstrate that SCP-Se NPs may alleviate LPS-induced enteritis through their anti-inflammatory effects, indicating that SCP-Se NPs can serve as a good candidate for preventing and treating enteritis in the livestock and poultry industry.

3.
J Control Release ; 357: 274-286, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958401

RESUMO

The application of numerous chemotherapeutic drugs has been limited due to poor solubility, adverse side effects, and even multidrug resistance in patients. Polymeric micelles with reversibly cross-linked structures provide a promising solution to these issues. Herein, we optimized and synthesized programable-released disulfide cross-linked micelle (PDCM) based on our previous well-defined dendrimers to deliver the antitumor drug betulinic acid (BA) and paclitaxel (PDCM@PTX) and evaluated the therapeutic efficacy of multidrug-resistant (MDR) simulative orthotopic intraperitoneal ovarian cancer mice models. Comprehensive results demonstrated that PDCM@PTX formed stable nanoparticles able to improve the pharmacokinetic profile and circulation time of PTX, allowing for increased tumor penetration. Furthermore, in the tumor microenvironment, the programable-switches (ester bonds and disulfide cross-linking) of PDCM@PTX were cleaved by the high concentration of glutathione (tumor microenvironment) and esterase (intracellular) present in the tumor, allowing for in situ release of PTX and BA, resulting in intensive therapeutic efficacy in MDR ovarian cancer.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Paclitaxel/química , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Micelas , Dissulfetos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Microambiente Tumoral
4.
Nanoscale Adv ; 4(21): 4470-4480, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36341301

RESUMO

Nanomedicine based drug delivery platforms provide an interesting avenue to explore for the future of cancer treatment. Here we discuss the barriers for drug delivery in cancer therapeutics and how nanomaterials have been designed to bypass these blockades through stimuli responsive transformation in the most recent update. Nanomaterials that address the challenges of each step provide a promising solution for new cancer therapeutics.

5.
J Control Release ; 352: 371-384, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36309096

RESUMO

Probiotics have several health benefits to the host. However, low pH in the stomach, various digestive enzymes and bile salts in the intestine threaten their viability and function. Thus, probiotics need to be protected during gastric transit to address challenges associated with low viability and impaired function. At present, probiotic delivery systems with different trigger mechanisms have been constructed to successfully introduce numerous high-viability probiotics to the intestine. On this basis, the application of non-targeted/targeted probiotic delivery systems in different gut microenvironment and the adjuvant therapeutic effect of probiotic delivery systems on other disease were discussed in detail. It is important to also note that most of the current studies in this area focused on non-targeted probiotic delivery systems. Moreover, changes in intestinal microenvironment under disease state and discontinuous distribution of disease site limit their development. Thus, emphasis were made on the optimization of non-targeted probiotic delivery systems and the necessity of designing more precisely targeted ones.


Assuntos
Probióticos , Ácidos e Sais Biliares
6.
Angew Chem Int Ed Engl ; 61(35): e202204567, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35791769

RESUMO

Smart conversion of supramolecular structures in vivo is an attractive strategy in cancer nanomedicine, which is usually achieved via specific peptide sequences. Here we developed a lysosomal targeting small-molecule conjugate, PBC, which self-assembles into nanoparticles at physiological pH and smartly converts to nanofibrils in lysosomes of tumor cells. Such a transformation mechanically leads to lysosomal dysfunction, autophagy inhibition, and unusual cytoplasmic vacuolation, thus granting PBC a unique anticancer activity as a monotherapy. Importantly, the photo-activated PBC elicits significant phototoxicity to lysosomes and shows enormous advantages in overcoming autophagy-caused treatment resistance frequently occurring in conventional phototherapy. This improved phototherapy achieves a complete cure of oral cancer xenografts upon limited administration. Our work provides a new paradigm for the construction of nonpeptide nanotransformers with biomedical activities.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia , Humanos , Concentração de Íons de Hidrogênio , Lisossomos , Neoplasias/tratamento farmacológico , Neoplasias/patologia
7.
Acta Pharm Sin B ; 12(6): 2672-2682, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35755275

RESUMO

Hybrid lipid‒nanoparticle complexes have shown attractive characteristics as drug carriers due to their integrated advantages from liposomes and nanoparticles. Here we developed a kind of lipid-small molecule hybrid nanoparticles (LPHNPs) for imaging and treatment in an orthotopic glioma model. LPHNPs were prepared by engineering the co-assembly of lipids and an amphiphilic pheophorbide a‒quinolinium conjugate (PQC), a mitochondria-targeting small molecule. Compared with the pure nanofiber self-assembled by PQC, LPHNPs not only preserve the comparable antiproliferative potency, but also possess a spherical nanostructure that allows the PQC molecules to be administrated through intravenous injection. Also, this co-assembly remarkably improved the drug-loading capacity and formulation stability against the physical encapsulation using conventional liposomes. By integrating the advantages from liposome and PQC molecule, LPHNPs have minimal system toxicity, enhanced potency of photodynamic therapy (PDT) and visualization capacities of drug biodistribution and tumor imaging. The hybrid nanoparticle demonstrates excellent curative effects to significantly prolong the survival of mice with the orthotopic glioma. The unique co-assembly of lipid and small molecule provides new potential for constructing new liposome-derived nanoformulations and improving cancer treatment.

9.
Adv Funct Mater ; 31(10)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-37441230

RESUMO

Photodynamic therapy (PDT) has emerged as an attractive alternative in cancer therapy, but its therapeutic effects are limited by the nonselective subcellular localization and poor intratumoral retention of small-molecule photosensitizes. Here a fiber-forming nanophotosensitizer (PQC NF) that is composed of mitochondria targeting small molecules of amphiphilicity is reported. Harnessing the specific mitochondria targeting, the light-activated PQC NFs produce approximately 110-fold higher amount of reactive oxygen species (ROS) in cells than free photosensitizers and can dramatically induce mitochondrial disruption to trigger intense apoptosis, showing 20-50 times better in vitro anticancer potency than traditional photosensitizers. As fiber-shaped nanomaterials, PQC NFs also demonstrated a long-term retention in tumor sites, solving the challenge of rapid clearance of small-molecule photosensitizers from tumors. With these advantages, PQC NFs achieve a 100% complete cure rate in both subcutaneous and orthotopic oral cancer models with the administration of only a single dose. This type of single small molecule-assembled mitochondria targeting nanofibers offer an advantageous strategy to improve the in vivo therapeutic effects of conventional PDT.

10.
Nat Commun ; 11(1): 4615, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934241

RESUMO

Integration of the unique advantages of the fields of drug discovery and drug delivery is invaluable for the advancement of drug development. Here we propose a self-delivering one-component new-chemical-entity nanomedicine (ONN) strategy to improve cancer therapy through incorporation of the self-assembly principle into drug design. A lysosomotropic detergent (MSDH) and an autophagy inhibitor (Lys05) are hybridised to develop bisaminoquinoline derivatives that can intrinsically form nanoassemblies. The selected BAQ12 and BAQ13 ONNs are highly effective in inducing lysosomal disruption, lysosomal dysfunction and autophagy blockade and exhibit 30-fold higher antiproliferative activity than hydroxychloroquine used in clinical trials. These single-drug nanoparticles demonstrate excellent pharmacokinetic and toxicological profiles and dramatic antitumour efficacy in vivo. In addition, they are able to encapsulate and deliver additional drugs to tumour sites and are thus promising agents for autophagy inhibition-based combination therapy. Given their transdisciplinary advantages, these BAQ ONNs have enormous potential to improve cancer therapy.


Assuntos
Aminoquinolinas/química , Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Lisossomos/efeitos dos fármacos , Nanomedicina/métodos , Neoplasias/tratamento farmacológico , Aminoquinolinas/administração & dosagem , Aminoquinolinas/farmacocinética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/instrumentação , Humanos , Nanomedicina/instrumentação , Nanopartículas/química , Neoplasias/fisiopatologia , Ratos , Ratos Sprague-Dawley
11.
Anal Chem ; 92(18): 12282-12289, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32790290

RESUMO

Small-molecule fluorescent probes are powerful tools in chemical analysis and biological imaging. However, as the foundation of probe design, the meager existing set of core fluorophores have largely limited the diversity of current probes. Consequently, there is a high demand to discover fluorophores with new scaffolds and optimize the existing fluorophores. Here, we put forward a facile strategy of heterocyclic N-oxidation to address these challenges. The introduced N-O bond reconstructs the electron "push-pull" system of heterocyclic scaffolds and dramatically improves their photophysical properties by red-shifting the spectra and increasing the Stokes shift. Meanwhile, the heterocyclic N-O bond also enables a function of the fluorescence switch. It can turn on the fluorescence of pyridine and increase the fluorescence of quinoline and, conversely, decrease the fluorescence of acridines and resorufin. As a further practical application, we successfully utilized the quinoline N-oxide scaffold to design fluorogenic probes for H2S (8) and formaldehyde (FA, 9). Given their ultraviolet-visible spectra, both probes with high selectivity and sensitivity could be conveniently used in the naked eye detection of target analytes under illumination with a portable UV lamp. More interestingly, the probes could be effectively used in the imaging of nuclear and cytoplasmic H2S or nuclear and perinuclear FA. This potentially overcomes the weaknesses of existing H2S or FA probes that can only work in the cytoplasm. These interesting findings demonstrate the ability to rapidly expand and optimize the existing fluorophore library through heterocyclic N-oxidation.


Assuntos
Óxidos N-Cíclicos/química , Fluorescência , Corantes Fluorescentes/química , Formaldeído/análise , Sulfeto de Hidrogênio/análise , Bibliotecas de Moléculas Pequenas/química , Óxidos N-Cíclicos/síntese química , Corantes Fluorescentes/síntese química , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/síntese química
12.
Mol Biochem Parasitol ; 238: 111291, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32479776

RESUMO

In free-living and parasitic nematodes, the methylation of phosphoethanolamine to phosphocholine provides a key metabolite to sustain phospholipid biosynthesis for growth and development. Because the phosphoethanolamine methyltransferases (PMT) of nematodes are essential for normal growth and development, these enzymes are potential targets of inhibitor design. The pine wilt nematode (Bursaphelenchus xylophilus) causes extensive damage to trees used for lumber and paper in Asia. As a first step toward testing BxPMT1 as a potential nematicide target, we determined the 2.05 Å resolution x-ray crystal structure of the enzyme as a dead-end complex with phosphoethanolamine and S-adenosylhomocysteine. The three-dimensional structure of BxPMT1 served as a template for site-directed mutagenesis to probe the contribution of active site residues to catalysis and phosphoethanolamine binding using steady-state kinetic analysis. Biochemical analysis of the mutants identifies key residues on the ß1d-α6 loop (W123F, M126I, and Y127F) and ß1e-α7 loop (S155A, S160A, H170A, T178V, and Y180F) that form the phosphobase binding site and suggest that Tyr127 facilitates the methylation reaction in BxPMT1.


Assuntos
Etanolaminas/química , Proteínas de Helminto/química , Metiltransferases/química , Nematoides/enzimologia , Pinus/parasitologia , Doenças das Plantas/parasitologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Etanolaminas/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Cinética , Metiltransferases/genética , Metiltransferases/metabolismo , Modelos Moleculares , Nematoides/genética , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Termodinâmica
13.
Adv Mater ; 32(14): e1903759, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32078198

RESUMO

The efficacy of therapeutics for brain tumors is seriously hampered by multiple barriers to drug delivery, including severe destabilizing effects in the blood circulation, the blood-brain barrier/blood-brain tumor barrier (BBB/BBTB), and limited tumor uptake. Here, a sequential targeting in crosslinking (STICK) nanodelivery strategy is presented to circumvent these important physiological barriers to improve drug delivery to brain tumors. STICK nanoparticles (STICK-NPs) can sequentially target BBB/BBTB and brain tumor cells with surface maltobionic acid (MA) and 4-carboxyphenylboronic acid (CBA), respectively, and simultaneously enhance nanoparticle stability with pH-responsive crosslinkages formed by MA and CBA in situ. STICK-NPs exhibit prolonged circulation time (17-fold higher area under curve) than the free agent, allowing increased opportunities to transpass the BBB/BBTB via glucose-transporter-mediated transcytosis by MA. The tumor acidic environment then triggers the transformation of the STICK-NPs into smaller nanoparticles and reveals a secondary CBA targeting moiety for deep tumor penetration and enhanced uptake in tumor cells. STICK-NPs significantly inhibit tumor growth and prolong the survival time with limited toxicity in mice with aggressive and chemoresistant diffuse intrinsic pontine glioma. This formulation tackles multiple physiological barriers on-demand with a simple and smart STICK design. Therefore, these features allow STICK-NPs to unleash the potential of brain tumor therapeutics to improve their treatment efficacy.


Assuntos
Antineoplásicos/química , Barreira Hematoencefálica/metabolismo , Portadores de Fármacos/química , Nanopartículas/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Barreira Hematoencefálica/efeitos dos fármacos , Ácidos Borônicos/química , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Carbocianinas/química , Linhagem Celular Tumoral , Dissacarídeos/química , Gadolínio DTPA/química , Glioma/tratamento farmacológico , Glioma/mortalidade , Glioma/patologia , Humanos , Concentração de Íons de Hidrogênio , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Transcitose , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Indian Soc Periodontol ; 16(3): 430-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23162342

RESUMO

AIM: The purpose of the present study was to determine the prevalence and extent of gingival overgrowth in patients treated with calcium channel blockers for cardiovascular diseases. BACKGROUND: Calcium channel blockers are widely used in the treatment of hypertension, vasoplastic angina, and cardiacarrythmias. Gingival overgrowth resulting from the use of calcium channel blockers is of primary concern to dentists. The purpose of the present study is to determine the prevalence and extent of gingival overgrowth in patients treated with calcium channel blockers for various cardiovascular diseases, to assess their periodontal status and to correlate the factors like age, sex, duration, dosage, type of drugs that result in gingival overgrowth. MATERIALS AND METHODS: A cross-sectional study was done in cardiac patients treated with calcium channel blockers, visiting The Railway hospital, Perumbur, Chennai. Information regarding medical history, type, duration, dosage of medication were recorded and analyzed. The periodontal condition of the patients was assessed using the plaque index, gingival index, calculus index, papillary bleeding index, and extent of gingival overgrowth using appropriate indices. The data was later subjected to statistical analysis. RESULTS: In this study, a total of 213 cardiac patients (145 males and 68 females) who met the inclusion and exclusion criteria were screened. The patients were between 19 and 69 years. CONCLUSIONS: From the results of the present study it can be concluded that gingival overgrowth does occur with calcium channel blockers. Elderly males appeared to be more susceptible to the development of drug-induced gingival overgrowth, which was independent of dosage, duration of drug administered but the presence of local factors seemed to aggravate the same.

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