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1.
Front Pharmacol ; 14: 1281067, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38293667

RESUMO

Small molecule compounds targeting multiple kinases involved in neoangiogenesis have shown survival benefits in patients with unresectable hepatocellular carcinoma (HCC). Nonetheless, despite the beneficial effects of multikinase inhibitors (MKIs), a lack of boosting adjuvant limits their objective response rate. Lipid conjugates have been used to improve delivery efficacy or pharmaceutical benefits for decades. However, the feasibility of utilizing lipid-drug conjugates (LDCs) in HCC regimens remains untested. In this study, oral feeding of linoleate-fluorescein isothiocyanate conjugates showed that the compound was well distributed in a spontaneous HCC mouse model. Therefore, a rationale design was developed for chemically synthesizing a linoleate-pazopanib conjugate (LAPC). The LAPC showed a significantly improved cytotoxicity compared to the parental drug pazopanib. Pazopanib's angiogenic suppressing signals were not observed in LAPC-treated HCC cells, potentially suggesting an altered mechanism of action (MOA). In an efficacy trial comparing placebo, oral pazopanib, and LAPC treatments in the hepatitis B virus transgene-related spontaneous HCC mouse model (HBVtg-HCC), the LAPC treatment demonstrated superior tumor ablating capacity in comparison to both placebo and pazopanib treatments, without any discernible systemic toxicity. The LAPC exposure is associated with an apoptosis marker (Terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL]) and an enhanced ferroptosis (glutathione peroxidase 4 [GPX4]) potential in HBVtg-HCC tumors. Therefore, the LAPC showed excellent HCC ablative efficacy with altered MOA. The molecular mechanisms of the LAPC and LDCs for HCC therapeutics are of great academic interest. Further comprehensive preclinical trials (e.g., chemical-manufacture-control, toxicity, distribution, and pharmacokinetics/pharmacodynamics) are expected.

2.
Biomater Adv ; 141: 213117, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36155246

RESUMO

A versatile nanoformulation is designed by anchoring human transferrin protein (Tf) on fluoromagnetic upconverting nanoheaters, NaGdF4:Yb,Er (UCNP), loaded with Rose Bengal (RB), for multimodal imaging guided synergistic photothermal (PTT) and photodynamic therapy (PDT) at the targeted tumor site. The NIR excitation of the UCNP-RB Forster Resonance Energy Transfer (FRET) pair results in the reactive oxygen species (ROS) generation for PDT, whereas the non-radiative transitions in Er result in the heat required for PTT. The intravenously injected theranostic agent (UCNP@Tf-RB) enabled; (1) combinatorial PTT and PDT of 4T1 tumors with minimal systemic toxicity, (2) dual targeted (passive and active) tumor accumulation, (3) dual-modal imaging (MRI/photothermal), and, (4) excellent stability and biocompatibility. The in vitro therapy data corroborates the MRI findings that Tf conjugation resulted in actively targeted tumor accumulation via over-expressed transferrin receptors (TfR) on 4T1 cells. Real-time photothermal imaging enabled visualization of the tumor while receiving the therapy. The UCNP@Tf-RB, for synergistic PTT-PDT, and UCNP@Tf, for PTT only, caused rapid suppression of tumor with a tumor-growth inhibition index (TGII) of ~0.91, and 0.79, respectively. Histopathological examination demonstrated minimal damage to non-targeted tissues and caused significant damage to the tumor. This theranostic methodology enhances anti-cancer therapeutic efficiency, and announces the potential for pre-clinical cancer therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/diagnóstico por imagem , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/uso terapêutico , Receptores da Transferrina/uso terapêutico , Rosa Bengala/uso terapêutico , Transferrina/uso terapêutico
3.
Mater Sci Eng C Mater Biol Appl ; 101: 169-178, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029310

RESUMO

An electrokinetic potential (ζ-potential) based approach was introduced to address the amyloid degradation on ZnO-nanoflower platform. The hallmark of neurodegenerative disorders like Alzheimer's disease, Parkinson's disease (PD), Creutzfeldt-Jakob Disease (CJD), Prion- associated diseases, type-II diabetes, etc. is the deposition of misfolded protein aggregates predominantly ß-sheeted in structure and fibrillar morphology, known as amyloids, in the brain and different parts of the body. Agents that can degrade these amyloids can be potential candidate for the therapy of amyloidosis. Ultrasmall nanoparticles are gaining interest due to their ability to cross blood brain barrier (BBB) which is favorable for the treatment of neurodegenerative disorders. Considering the influence of Zn2+ in the formation of Aß aggregates instead of fibrillation, the present study was designed based on the ZnO nanoparticles (ZnO-NP) and ZnO nanoflowers (ZnO-NF) to compare the anti amyloid ability using a model huminsulin amyloid. Fluorescence study, atomic force microscopy (AFM), IR spectroscopy (FTIR) and reduction of fibril size using dynamic light scattering showed that ZnO-NF can degrade amyloids with a higher capacity than their nanoparticle counterpart. Significant reduction in magnitude of ζ-potential in ZnO-NF treated huminsulin amyloid supported the notion to come to the consensus and became the new indicator for anti-amyloidosis. The cell viability assay of ZnO-NP and ZnO-NF at a higher dose than that used for amyloid degradation using PC12 and HaCaT cell lines showed their biocompatibility in a safe manner. Thus, it can be suggested that ZnO-NF would be a better candidate for amyloid degradation compared to ZnO-NPs due to higher surface to volume ratio of the petals.


Assuntos
Amiloide/química , Eletroquímica , Nanopartículas/química , Óxido de Zinco/química , Animais , Materiais Biocompatíveis/química , Difusão Dinâmica da Luz , Humanos , Insulina/química , Nanopartículas/ultraestrutura , Células PC12 , Tamanho da Partícula , Proteólise , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
4.
ACS Appl Bio Mater ; 2(1): 533-543, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35016317

RESUMO

A combined photothermal therapy (PTT) and chemotherapy (chemo) were performed in vitro on B16F10 melanoma cells and in vivo using melanoma bearing C57BL/6 mice. The 785 nm (100 mW) irradiated gold nanorods (AuNRs) were used as the PT agent, and electrostatically conjugated Doxorubicin (Dox) to a nanocarrier graphene oxide (GO) worked as the chemotherapeutic. Selection of dosage was optimized from the individual viability studies, and finally a combined therapeutic (AuNR (100 ppm), GO (125, and 250 ppm), Dox (0.0058, and 0.00058 ppm)), was delivered in vitro. PTT, followed by chemo, sequentially, resulted in <10% viability, whereas simultaneous PTT with chemo resulted in a viability of ∼40% for the melanoma cells. Flow cytometry indicated optical inhomogeneity in the cells that internalized GO, and AuNR; however, the Dox amount was identical within the cells treated with or without PTT. Confocal microscopy revealed that GO+Dox was internalized, and Dox was distributed uniformly within the cells irrespective of the treatment protocol. In vivo results in melanoma bearing C57BL/6 mice resembled the in vitro data closely. The tumor growth inhibition index was highest at 0.78 for the group receiving sequential treatment, followed by 0.61 for those receiving simultaneous treatment, where the control group had a score of 0. For the sequential treatment, presoftening of the cells with PTT, followed by the chemo resulted in significantly improved toxicity of the treatment, whereas simultaneous PTT with chemo results were dominated by the Dox alone.

5.
ACS Appl Bio Mater ; 2(4): 1634-1642, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35026897

RESUMO

The combination of superparamagnetism and excitation independency have been packed into carbon-decorated ferrite nanodots (CDs@MNFs) for the introduction of a cost-effective and less-toxic multimodal contrast agent in fluorescence/MR imaging to replace conventional heavy metal containing Gd-DOTA. The label-free surface engineered ferrite nanodots are capable of generating twin T1 (longitudinal) and T2 (transverse) weighted magnetic resonance (MR) along with fluorescence emission. The calculated molar relaxivities and molar radiant efficiency obtained from in vitro and in vivo studies are the indication of its multimodal efficacy in medical imaging compared to the conventional contrast agents. The cellular internalization of nanodots was established by confocal microscopy and flow cytometric assay, whereas the hemolysis and cell viability assays support their appreciable toxicity. Furthermore, the surface chemistry due to the presence of -COOH was utilized to attach the anticancer agent, doxorubicin (-NH2) making it an external stimuli responsive drug delivery vehicle for the treatment of cancer. Given the ease of fabrication, negligible toxicity, and significant contrast enhancement with stimuli responsive drug release kinetics CDs@MNFs prove to be a potential, cost-effective multimodal imaging agent which could be used for theragnosis.

6.
Curr Drug Deliv ; 16(3): 233-241, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30451110

RESUMO

OBJECTIVE: The label free ultrasmall fluorescent ferrite clusters have been engineered in a controlled fashion which was stabilized by serum protein and functionalized by folic acid for the application of targeted multimodal optical and Magnetic Resonance (MR) cancer imaging. METHODS: The ultra-small manganese ferrite nanoclusters (PMNCs) with a diameter of 4 nm have a commendable effect on the longitudinal (T1) and transverse (T2) relaxation in MR imaging that was evident from the phantom and animal MRI. RESULTS: The calculated longitudinal molar relaxivity of nanoclusters was found to be 6.9 ± 0.10 mM-1 S-1 which was exactly 2.22 times better than the conventional Gd-DOTA and their 4.01 ratio of the transverse (r2) and longitudinal (r1) relaxivities made them a potential candidate for both T1 and T2 contrast agents in MRI. In addition, the fluorescence-based small animal imaging showed folic acid driven accumulated fluorescent signal at the tumour site to conclude the capacity of PMNCs for targeted fluorescence imaging of cancer diagnosis. CONCLUSION: The cytotoxicity assay and histopathology studies were the evidence for their safe biodistribution in animal systems. Furthermore, the protein encapsulated clusters have the ability to deliver the anticancer drug Methotrexate (MTX) to the cancer tissues with a sustained manner. Therefore, one can conclude the remarkable efficacy of architect nanoclusters for theragnosis.


Assuntos
Sistemas de Liberação de Medicamentos , Compostos Férricos/administração & dosagem , Compostos de Manganês/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fluorescência , Ácido Fólico/administração & dosagem , Humanos , Fenômenos Magnéticos , Imageamento por Ressonância Magnética , Masculino , Metotrexato/administração & dosagem , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Soroalbumina Bovina/administração & dosagem
7.
Mater Sci Eng C Mater Biol Appl ; 78: 960-968, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28576073

RESUMO

Zinc oxide (ZnO) is a semiconductor metal oxide nanoparticle with inherent optical properties. Among the different zinc oxide nanostructures, nanoflowers have greater surface area. Utilizing this property a reagentless biosensor has been developed for the detection of beta amyloids, a hallmark of neurodegenerative diseases like Alzheimer's disease, Creutzfeldt-Jakob Syndrome, insulin dependent type II diabetes etc. The poor fluorescence quantum yield and photobleaching effect of Thioflavin T (ThT) upon binding to the model insulin amyloid beta sheets in solution can be overcome by the present engineered biosensor where ThT acts as a target as well as a reporter to detect amyloids adsorbed on a solid template based on ZnO nanoflower. ThT was adsorbed on ZnO NFs grown over nano-silver thin film coated glass slide. The in vivo imaging system was used to detect and quantify the fluorescence intensity generated from the substrates upon binding with insulin amyloid. ZnO NFs have the waveguiding property which increases the local field intensity caused by a resonance between the guided fundamental mode and evanescent field associated with high- order modes. This resonance phenomenon reinforces the excitation of the fluorophores in close proximity of the NFs thereby exhibiting enhanced fluorescence like Fabry Pero't Resonator (FPR). Considering the engineering and sensitivity, the reported nanobiosensor developed on ZnO nanoflower can be treated as faster and cost effective amyloid sensor.


Assuntos
Nanoestruturas , Amiloide , Técnicas Biossensoriais , Diabetes Mellitus Tipo 2 , Humanos , Óxido de Zinco
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