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1.
Cytometry A ; 105(4): 252-265, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38038631

RESUMO

Mesenchymal stem cells (MSCs) being injected into the body can stimulate or decelerate carcinogenesis. Here, the direction of influence of human placenta-derived MSCs (P-MSCs) on the Lewis lung carcinoma (LLC) tumor development and metastatic potential is investigated in C57BL/6 mice depending on the injection method. After intramuscular co-inoculation of LLC and P-MSCs (LLC + P-MSCs), the growth of primary tumor and angiogenesis are slowed down compared to the control LLC on the 15th day. This is explained by the fact of a decrease in the secretion of proangiogenic factors during in vitro co-cultivation of an equal amount of LLC and P-MSCs. When P-MSCs are intravenously (i.v.) injected in the mice with developing LLC (LLC + P-MSCs(i.v.)), the tumor growth and angiogenesis are stimulated on the 15th day. A highly activated secretion of proangiogenic factors by P-MSCs in a similar in vitro model can explain this. In both the models compared to the control on the 23rd day, there is no significant difference in the tumor growth, while angiogenesis remains correspondingly decelerated or stimulated. However, in both the models, the total volume and number of lung metastases constantly increase compared to the control: it is mainly due to small-size metastases for LLC + P-MSCs(i.v.) and larger ones for LLC + P-MSCs. The increase in the rate of LLC cell dissemination after the injection of P-MSCs is explained by the disordered polyploidy and chromosomal instability, leading to an increase in migration and invasion of cancer cells. After LLC + P-MSCs co-inoculation, the tumor cell karyotype has the most complex and heterogeneous chromosomal structure. These findings indicate a bidirectional effect of P-MSCs on the growth of LLC in the early periods after injection, depending on the injection method, and, correspondingly, the number of contacting cells. However, regardless of the injection method, P-MSCs are shown to increase LLC aggressiveness related to cancer-associated angiogenesis and metastasis activation in the long term.


Assuntos
Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Carcinoma Pulmonar de Lewis/patologia , Camundongos Endogâmicos C57BL , Neoplasias Pulmonares/patologia
2.
Small ; 19(8): e2205165, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36508710

RESUMO

The conventional approach in cancer nanomedicine involves advanced drug nanocarriers delivering preloaded therapeutics to targeted tumor sites to maximize drug efficiency. However, both cancer drugs and nanocarriers inevitably produce side effects and systemic toxicity. Herein, hemoglobin nanocrystals (HbC) as drug-free theranostic nanoformulations with the tumor microenvironment (TME) activated diagnostic and therapeutic abilities towards colon tumors are introduced. HbC can release Fe2+ oxidized to Fe3+ in the Fenton reaction with tumor endogenous H2 O2 , concurrently with the generation of cytotoxic hydroxyl radicals (•OH) that allow for chemodynamic therapy (CDT). Furthermore, in situ-produced Fe3+ reacts with colon tumor-abundant H2 S, resulting in the production of Fe1- x S, which provides magnetic resonance imaging (MRI) contrast and allows for NIR light-inducible photothermal therapy (PTT). In vitro and in vivo studies revealed that HbC produced CDT towards 4T1 tumors, and MRI-guided, synergistically enhanced combination of CDT and PTT against H2 S abundant colon tumors (CT26), with negligible toxicity towards normal tissues, enlightening HbC as highly efficient and biocompatible TME activated theranostic nanoplatform specific against colon cancer without any traditional drugs and drug carriers.


Assuntos
Antineoplásicos , Neoplasias do Colo , Nanopartículas , Neoplasias , Humanos , Linhagem Celular Tumoral , Medicina de Precisão , Nanopartículas/química , Antineoplásicos/farmacologia , Neoplasias/terapia , Neoplasias do Colo/tratamento farmacológico , Microambiente Tumoral , Nanomedicina Teranóstica , Peróxido de Hidrogênio/farmacologia
3.
Am J Physiol Gastrointest Liver Physiol ; 322(1): G142-G153, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851733

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, which is not sensitive to radiotherapy and chemotherapy and very often experiences postoperative relapse. In this regard, effective screening of liver cancer is considered as the most important and urgent task. The aim of our study was to determine whether N-methyl-D-aspartate receptor (NMDAR) and, in particular, its subunits, can serve as biomarkers to distinguish the precancerous liver at early stages of liver fibrosis. We assessed the development of HCC after 10, 15, and 22 wk using a HCC rat model. The expression of NMDAR subunits was monitored at different stages of HCC by means of immunohistochemistry combined with epifluorescence microscopy imaging, Western blotting, and direct bisulfite sequencing. NMDAR subunits were not found in healthy liver tissues. In contrast, NMDAR subunits, in particular NR1 and NR2B, appeared at the stage of severe liver fibrosis (precancerous liver disease) in rats and were expressed during the development of HCC in rats and mice. Using the direct bisulfite sequencing, we detected that increased expression of NMDAR directly correlated with the demethylation of CpG islands in the promoter region of genes encoding receptor subunits. The obtained results confirmed that NMDAR subunits can serve as new biomarkers of precancerous liver disease, severe fibrosis, and its progression towards HCC.NEW & NOTEWORTHY We have shown NMDAR expression in cell transformation process at early stages of cancer, specifically HCC. The aim of our study was to define the disease stages from precancerous liver disease towards liver cancer progression when NMDAR subunits were expressed/detected. A fibrosis/HCC rat model, immunohistochemistry combined with epifluorescence microscopy imaging, Western blotting was used. The dynamics of appearance of NMDAR subunits, their expression and methylation status during the development of HCC were shown and discussed.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais/fisiologia , Animais , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , RNA Mensageiro/metabolismo , Ratos , Roedores/genética , Roedores/metabolismo
4.
Small ; 17(41): e2103569, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34532978

RESUMO

Photodynamic therapy (PDT) is a well-known method for cancer therapy in the clinic. However, the inherent hypoxia microenvironment of solid tumors enormously restricts the PDT efficiency. Herein, catalase nanocrystals (CatCry) are introduced as in situ oxygen (O2 )-generating system to relieve tumor hypoxia and enhance PDT efficiency for solid tumors. After loading with photosensitizer methylene blue (MB), a PDT drug platform (CatCry-MB) emerges, allowing for significant increasing PDT efficiency instigated by three factors. First, the high stability and recyclable catalytic activity of CatCry enable a long-term endogenous H2 O2 decomposition for continuous O2 supply for sustained relief of tumor hypoxia. Second, both the produced O2 and loaded MB are confined within CatCry nanoporous structure, shortening the diffusion distance between O2 and MB to maximize the production of singlet oxygen (1 O2 ). Third, the MB molecules are uniformly dispersed within CatCry lattice, avoiding MB aggregation and causing more MB molecules be activated to produce more 1 O2 . With the three complementary mechanisms, tumor hypoxia is eradicated and the resulted enhancement in PDT efficiency is demonstrated in vitro and in vivo. The proposed approach opens up a new venue for the development of other O2 -dependent tumor treatments, such as chemotherapy, radiotherapy, and immunotherapy.


Assuntos
Nanopartículas , Fotoquimioterapia , Catalase , Linhagem Celular Tumoral , Humanos , Hipóxia/tratamento farmacológico , Azul de Metileno , Oxigênio , Fármacos Fotossensibilizantes/uso terapêutico
5.
Nanomedicine ; 29: 102269, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32679268

RESUMO

X-ray CT imaging can be complementary to fluorescence and photoacoustic imaging (FLI and PAI), allowing for high spatial resolution and high-sensitivity multimodal imaging for imaging guided treatment. In this study, the CT contrast agent iohexol was co-encapsulated with indocyanine green (ICG) within nanoliposomes (NLs) to explore their interaction and possible application of this liposomal formulation (LGI) in cancer theranostics. The photophysical properties of LGI were studied to assess the effect of iohexol on ICG that can enhance the efficiency of ICG-based near infrared photodynamic therapy (PDT). The CT, FLI and PA imaging abilities of LGI were also investigated. Furthermore, the near infrared phototherapy of cancer cells in vitro was performed, exhibiting higher phototherapy efficacy of LGI in comparison with other ICG formulations. We conclude that LGI can serve as a highly efficient theranostic nanoplatform for multimodal (fluorescence, CT and PA) imaging and near infrared phototherapy.


Assuntos
Meios de Contraste/farmacologia , Verde de Indocianina/farmacologia , Nanoestruturas/química , Neoplasias/terapia , Linhagem Celular Tumoral , Meios de Contraste/química , Diagnóstico por Imagem/tendências , Humanos , Verde de Indocianina/química , Raios Infravermelhos/uso terapêutico , Lipossomos/química , Lipossomos/farmacologia , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Fototerapia/tendências , Tomografia Computadorizada por Raios X/métodos
6.
J Cell Physiol ; 234(9): 15989-16002, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30741423

RESUMO

Red and near-infrared (NIR) light effect on Ca2+ ions flux through the influence on N-methyl-D-aspartate receptors (NMDARs) and their functioning in HeLa cells was studied in vitro. Cells were irradiated by 650 and 808 nm laser light at different power densities and doses and the obtained effect was compared with that caused by the pharmacological agents. The laser light was found to elevate Ca2+ influx into cell cytoplasm in a dose-dependent manner without changes of the NMDAR functioning. Furthermore, the light of both wavelengths demonstrated the ability to elevate Ca2+ influx under the pharmacological blockade of NMDARs and also might partially abolish the blockade enhancing Ca2+ influx after selective stimulation of the receptors with NMDA. Simultaneously, the light at moderate doses demonstrated a photobiostimulating effect on cells. Based on our experiments and data reported in the literature, we suggest that the low-power visible and NIR light can instigate a cell membrane depolarization via nonthermal activation, resulting in the fast induction of Ca2+ influx into cells. The obtained results also demonstrate that NIR light can be used for nonthermal and nonpharmacological stimulation of NMDARs in cancer cells.

7.
Cytometry A ; 95(1): 24-33, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30240134

RESUMO

This study is aimed to reveal morphological and functional changes in multipotent mesenchymal stromal cells (MSCs) isolated from the rat bone marrow after: (i) activation of Toll-like receptors (TLRs) with teichoic acid (TA), (ii) impact on epidermal growth factor (EGF) receptors with activator EGF or inhibitor Herceptin, and (iii) treatment with DNA intercalator Cisplatin. According to our results, TA and EGF cause an increase in the synthesis of glycosaminoglycans, c-Myc content, and protein in the MSC cytoplasm. It was observed that the cell population in G0 phase decreased and the cell population in G1 phase increased, when compared with control. At the same time, the cell population with a higher nuclear-cytoplasmic ratio (NCR) in S and G2 phases also increased. This indicates the manifestation of the MSC mesenchymal phenotype, exhibiting indirect metabolic signs of the regenerative potential increase. In other experiments, Herceptin was shown to suppress only the stemness signs of MSCs, while Cisplatin seriously affected cell viability in general, reducing synthetic and proliferative activities and causing cell morphology disturbances. © 2018 International Society for Advancement of Cytometry.


Assuntos
Cisplatino/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Animais , Células da Medula Óssea/química , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Receptores ErbB/agonistas , Receptores ErbB/antagonistas & inibidores , Citometria de Fluxo , Glicogênio/metabolismo , Glicosaminoglicanos/biossíntese , Glicosaminoglicanos/metabolismo , Humanos , Substâncias Intercalantes/farmacologia , Masculino , Células-Tronco Mesenquimais/química , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ácidos Teicoicos/farmacologia , Receptores Toll-Like/metabolismo , Trastuzumab/farmacologia
8.
J Immunol ; 197(5): 1631-41, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27456485

RESUMO

T lymphocytes play a central role in many human immunologic disorders, including autoimmune and alloimmune diseases. In hematopoietic stem cell transplantation, acute graft-versus-host-disease (GVHD) is caused by an attack on the recipient's tissues from donor allogeneic T cells. Selectively depleting GVHD-causing cells prior to transplant may prevent GVHD. In this study, we evaluated 24 chalcogenorhodamine photosensitizers for their ability to selectively deplete reactive T lymphocytes and identified the photosensitizer 2-Se-Cl, which accumulates in stimulated T cells in proportion to oxidative phosphorylation. The photosensitizer is also a potent stimulator of P-glycoprotein (P-gp). Enhanced P-gp activity promotes the efficient removal of photosensitizer not sequestered in mitochondria and protects resting lymphocytes that are essential for antipathogen and antitumor responses. To evaluate the selective depletion of alloimmune responses, donor C57BL/6 splenocytes were cocultured for 5 d with irradiated BALB/c splenocytes and then photodepleted (PD). PD-treated splenocytes were infused into lethally irradiated BALB/c (same-party) or C3H/HeJ (third-party) mice. Same-party mice that received PD-treated splenocytes at the time of transplant lived 100 d without evidence of GVHD. In contrast, all mice that received untreated primed splenocytes and third-party mice that received PD-treated splenocytes died of lethal GVHD. To evaluate the preservation of antiviral immune responses, acute lymphocytic choriomeningitis virus infection was used. After photodepletion, expansion of Ag-specific naive CD8(+) T cells and viral clearance remained fully intact. The high selectivity of this novel photosensitizer may have broad applications and provide alternative treatment options for patients with T lymphocyte-mediated diseases.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/imunologia , Linfócitos T CD8-Positivos/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Depleção Linfocítica/métodos , Subfamília B de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Metabolismo Energético , Doença Enxerto-Hospedeiro/imunologia , Humanos , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Fármacos Fotossensibilizantes/isolamento & purificação , Fármacos Fotossensibilizantes/farmacologia , Transplante Homólogo
9.
Chem Soc Rev ; 46(14): 4150-4167, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28621356

RESUMO

Lanthanide-doped upconversion nanoparticles (UCNPs) are promising for applications as wide as biological imaging, multimodal imaging, photodynamic therapy, volumetric displays, and solar cells. Yet, the weak and narrow absorption of lanthanide ions poses a fundamental limit of UCNPs to withhold their brightness, creating a long-standing hurdle for the field. Dye-sensitized UCNPs are emerging to address this performance-limiting problem, yielding up to thousands-fold brighter luminescence than conventional UCNPs without dye sensitization. In their configuration, organic dyes with spectrally broad and intense absorption are anchored to the surface of UCNPs to harvest the excitation light energy, which is then transferred via Förster and/or Dexter mechanisms across the organic/inorganic interface to the lanthanides incorporated in UCNPs (with or devoid of a shell) to empower efficient upconversion. This tutorial review highlights recent progress in the development of dye sensitized UCNPs, with an emphasis on the theory of energy transfer, the geometric classification of the dye sensitized core and core/shell nanocrystals, and their emerging photonic and biophotonic applications. Opportunities and challenges offered by dye sensitized UCNPs are also discussed.

10.
J Am Chem Soc ; 138(50): 16192-16195, 2016 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-27935695

RESUMO

We introduce a hybrid organic-inorganic system consisting of epitaxial NaYF4:Yb3+/X3+@NaYbF4@NaYF4:Nd3+ (X = null, Er, Ho, Tm, or Pr) core/shell/shell (CSS) nanocrystal with organic dye, indocyanine green (ICG) on the nanocrystal surface. This system is able to produce a set of narrow band emissions with a large Stokes-shift (>200 nm) in the second biological window of optical transparency (NIR-II, 1000-1700 nm), by directional energy transfer from light-harvesting surface ICG, via lanthanide ions in the shells, to the emitter X3+ in the core. Surface ICG not only increases the NIR-II emission intensity of inorganic CSS nanocrystals by ∼4-fold but also provides a broadly excitable spectral range (700-860 nm) that facilitates their use in bioapplications. We show that the NIR-II emission from ICG-sensitized Er3+-doped CSS nanocrystals allows clear observation of a sharp image through 9 mm thick chicken breast tissue, and emission signal detection through 22 mm thick tissue yielding a better imaging profile than from typically used Yb/Tm-codoped upconverting nanocrystals imaged in the NIR-I region (700-950 nm). Our result on in vivo imaging suggests that these ICG-sensitized CSS nanocrystals are suitable for deep optical imaging in the NIR-II region.

11.
Chem Soc Rev ; 44(6): 1680-713, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25335878

RESUMO

Light upconverting nanostructures employing lanthanide ions constitute an emerging research field recognized with wide ramifications and impact in many areas ranging from healthcare, to energy and, to security. The core-shell design of these nanostructures allows us to deliberately introduce a hierarchy of electronic energy states, thus providing unprecedented opportunities to manipulate the electronic excitation, energy transfer and upconverted emissions. The core-shell morphology also causes the suppression of quenching mechanisms to produce efficient upconversion emission for biophotonic and photonic applications. Using hierarchical architect, whereby each shell layer can be defined to have a specific feature, the electronic structure as well as the physiochemical structure of the upconverting nanomaterials can be tuned to couple other electronic states on the surface such as excitations of organic dye molecules or localized surface plasmons from metallic nanostructures, or to introduce a broad range of imaging or therapeutic modalities into a single conduct. In this review, we summarize the key aspects of nanophotonic control of the light upconverting nanoparticles through governed design and preparation of hierarchical shells in the core-shell nanostructures, and review their emerging applications in the biomedical field, solar energy conversion, as well as security encoding.

12.
Nano Lett ; 15(11): 7400-7, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26487489

RESUMO

Lanthanide-doped upconversion nanoparticles hold promises for bioimaging, solar cells, and volumetric displays. However, their emission brightness and excitation wavelength range are limited by the weak and narrowband absorption of lanthanide ions. Here, we introduce a concept of multistep cascade energy transfer, from broadly infrared-harvesting organic dyes to sensitizer ions in the shell of an epitaxially designed core/shell inorganic nanostructure, with a sequential nonradiative energy transfer to upconverting ion pairs in the core. We show that this concept, when implemented in a core-shell architecture with suppressed surface-related luminescence quenching, yields multiphoton (three-, four-, and five-photon) upconversion quantum efficiency as high as 19% (upconversion energy conversion efficiency of 9.3%, upconversion quantum yield of 4.8%), which is about ~100 times higher than typically reported efficiency of upconversion at 800 nm in lanthanide-based nanostructures, along with a broad spectral range (over 150 nm) of infrared excitation and a large absorption cross-section of 1.47 × 10(-14) cm(2) per single nanoparticle. These features enable unprecedented three-photon upconversion (visible by naked eye as blue light) of an incoherent infrared light excitation with a power density comparable to that of solar irradiation at the Earth surface, having implications for broad applications of these organic-inorganic core/shell nanostructures with energy-cascaded upconversion.

13.
Bioorg Med Chem ; 23(15): 4501-4507, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26105712

RESUMO

We examined two selenorhodamines with amide and thioamide functionality at the 5-position of a 9-(2-thienyl) substituent on the selenoxanthylium analogue of the Texas-red core for their potential as photosensitizers for photodynamic therapy (PDT) in P-glycoprotein (P-gp)-expressing Colo-26 cells. These compounds were examined for their photophysical properties (absorption, fluorescence, and ability to generate singlet oxygen), for their uptake into Colo-26 cells in the absence or presence of verapamil, for their dark and phototoxicity toward Colo-26 cells, and for their co-localization with mitochondrial-specific agents in Colo-26 cells. Both compounds were extremely effective photosensitizers with values of EC50 ⩽ 4 × 10(-8)M toward Colo-26 cells with 1.0 J cm(-2) laser light delivered at 630 ± 2 nm.


Assuntos
Compostos Organosselênicos/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Rodaminas/uso terapêutico , Xantenos/química , Linhagem Celular Tumoral , Humanos , Mitocôndrias/metabolismo , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacocinética , Compostos Organosselênicos/toxicidade , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/toxicidade , Rodaminas/química , Rodaminas/farmacocinética , Rodaminas/toxicidade , Oxigênio Singlete/metabolismo , Espectrometria de Fluorescência
14.
Opt Lett ; 39(6): 1386-9, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24690794

RESUMO

In this work, we report on efficient visible and near-IR upconversion emissions in colloidal hexagonal-phase core/shell NaYF4:Er(3+)/NaYF4 nanoparticles (∼38 nm) under IR laser excitation at 1523 nm. Varying amounts of Er(3+) dopants were introduced into the core NaYF4:Er(3+) nanoparticles, revealing an optimized Er(3+) concentration of 10% for the highest luminescent efficiency. An inert epitaxial shell layer of NaYF4 grown onto the core of the NaYF4:Er(3+) 10% nanoparticle increased its upconversion emission intensity fivefold due to suppression of surface-related quenching mechanisms, yielding the absolute upconversion efficiency to be as high as ∼3.9±0.3% under an excitation density of 18 W/cm(2). The dependence of the intensity of upconversion emission peaks on laser excitation density in the core/shell nanoparticle displayed "saturation effects" at low excitation density in the range of 1.5-18 W/cm(2), which again demonstrates high upconversion efficiency.


Assuntos
Érbio/química , Fluoretos/química , Fluoretos/efeitos da radiação , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Ítrio/química , Ítrio/efeitos da radiação , Coloides/química , Coloides/efeitos da radiação , Transferência de Energia , Érbio/efeitos da radiação , Raios Infravermelhos , Teste de Materiais
15.
Biomed Opt Express ; 15(2): 924-937, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38404313

RESUMO

In vivo near infrared (NIR) fluorescence imaging and laser speckle contrast imaging (LSCI) are emerging optical bioimaging modalities, which can provide information on blood vessels morphology, volume and the blood flow velocity. Optical tissue clearing (OTC) technique addresses a light scattering problem in optical bioimaging, which is imperative for the transcranial brain imaging. Herein, we report an approach combining NIR fluorescence and LSC microscopy imaging with OTC. A liposomal nanoformulation comprising NIR fluorescent dye ICG and photosensitizer BPD was synthesized and injected intravenously into mouse with OTC treated skull. Transcranial excitation of BPD in nanoliposomes resulted in the localized, irradiation dose dependent photodynamic damage of the brain blood vessels, which was manifested both in NIR fluorescence and LSC transcranial imaging, revealing changes in the vessels morphology, volume and the blood flow rate. The developed approach allows for bimodal imaging guided, localized vascular PDT of cancer and other diseases.

16.
J Photochem Photobiol B ; 250: 112816, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029664

RESUMO

Although photobiomodulation (PBM) and gamma visual stimulatqion (GVS) have been overwhelmingly explored in the recent time as a possible light stimulation (LS) means of Alzheimer's disease (AD) therapy, their effects have not been assessed at once. In our research, the AD mouse model was stimulated using light with various parameters [continuous wave (PBM) or 40 Hz pulsed visible LED (GVS) or 40 Hz pulsed 808 nm LED (PBM and GVS treatment)]]. The brain slices collected from the LS treated AD model mice were evaluated using (i) fluorescence microscopy to image thioflavine-S labeled amy-loid-ß (Aß) plaques (the main hallmark of AD), or (ii) two-photon excited fluorescence (TPEF) imaging of unlabeled Aß plaques, showing that the amount of Aß plaques was reduced after LS treatment. The imaging results correlated well with the results of Morris water maze (MWM) test, which demonstrated that the spatial learning and memory abilities of LS treated mice were noticeably higher than those of untreated mice. The LS effect was also assessed by in vivo nonlinear optical imaging, revealing that the cerebral amyloid angiopathy decreased spe-cifically as a result of 40 Hz pulsed 808 nm irradiation, on the contrary, the angiopathy reversed after visible 40 Hz pulsed light treatment. The obtained results provide useful reference for further optimization of the LS (PBM or GVS) parameters to achieve efficient phototherapy of AD.


Assuntos
Doença de Alzheimer , Terapia com Luz de Baixa Intensidade , Camundongos , Animais , Estimulação Luminosa , Terapia com Luz de Baixa Intensidade/métodos , Encéfalo/metabolismo , Placa Amiloide , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Camundongos Transgênicos
17.
J Am Chem Soc ; 135(45): 16766-9, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24168622

RESUMO

The tetrazole-based photoclick chemistry has provided a powerful tool to image proteins in live cells. To extend photoclick chemistry to living organisms with improved spatiotemporal control, here we report the design of naphthalene-based tetrazoles that can be efficiently activated by two-photon excitation with a 700 nm femtosecond pulsed laser. A water-soluble, cell-permeable naphthalene-based tetrazole was identified that reacts with acrylamide with the effective two-photon cross-section for the cycloaddition reaction determined to be 3.8 GM. Furthermore, the use of this naphthalene-tetrazole for real-time, spatially controlled imaging of microtubules in live mammalian cells via the fluorogenic, two-photon-triggered photoclick chemistry was demonstrated.


Assuntos
Corantes Fluorescentes/química , Microtúbulos/ultraestrutura , Naftalenos/química , Tetrazóis/química , Animais , Células CHO , Sobrevivência Celular , Química Click , Cricetulus , Microscopia de Fluorescência , Modelos Moleculares , Imagem Óptica , Fótons
18.
Small ; 9(19): 3213-7, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23696330

RESUMO

A family of upconverting nanoparticles (UCNPs) with a tunable UV enhancement is developed via a facile approach. The design leads to a maximum 9-fold enhancement in comparison with known optimal ß-phase core/shell UCNPs in water. A highly effective and rapid in situ real-time live-cell photoactivation is recorded for the first time with such nanoparticles.


Assuntos
Raios Infravermelhos , Luminescência , Nanopartículas/química , Fotoquímica/métodos , Raios Ultravioleta
19.
Chemistry ; 19(21): 6670-84, 2013 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-23526622

RESUMO

We report herein a simple and efficient approach to the synthesis of a variety of meso-substituted purpurinimides. The reaction of meso-substituted purpurinimide with N-bromosuccinimide regioselectively introduced a bromo functionality at the 20-position, which on further reaction with a variety of boronic acids under Suzuki reaction conditions yielded the corresponding meso-substituted analogues. Interestingly, the free base and the metalated analogues showed remarkable differences in photosensitizing efficacy (PDT) and tumor-imaging ability. For example, the free-base conjugate showed significant in vitro PDT efficacy, but limited tumor avidity in mice bearing tumors, whereas the corresponding Ni(II) derivative did not produce any cell kill, but showed excellent tumor-imaging ability at a dose of 0.3 µmol kg(-1) at 24, 48, and 72 h post-injection. The limited PDT efficacy of the Ni(II) analogue could be due to its inability to produce singlet oxygen, a key cytotoxic agent required for cell kill in PDT. Based on electrochemical and spectroelectrochemical data in DMSO, the first one-electron oxidation (0.52 V vs. SCE) and the first one-electron reduction (-0.57-0.67 V vs. SCE) of both the free base and the corresponding Ni(II) conjugates are centered on the cyanine dye, whereas the second one-electron reduction (-0.81 V vs. SCE) of the two conjugates is assigned to the purpurinimide part of the molecule. Reduction of the cyanine dye unit is facile and occurs prior to reduction of the purpurinimide group, which suggests that the cyanine dye unit as an oxidant could be the driving force for quenching of the excited triplet state of the molecules. An interaction between the cyanine dye and the purpurinimide group is clearly observed in the free-base conjugate, which compares with a negligible interaction between the two functional groups in the Ni(II) conjugate. As a result, the larger HOMO-LUMO gap of the free-base conjugate and the corresponding smaller quenching constant is a reason to decrease the intramolecular quenching process and increase the production of singlet oxygen to some degree.


Assuntos
Carbocianinas/síntese química , Níquel/química , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Animais , Bromosuccinimida/química , Carbocianinas/química , Fluorescência , Camundongos , Estrutura Molecular , Neoplasias/tratamento farmacológico , Imagem Óptica , Oxirredução , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Porfirinas/química , Oxigênio Singlete/química , Estereoisomerismo , Relação Estrutura-Atividade
20.
Nanomedicine ; 9(8): 1192-202, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23747741

RESUMO

We present a magnetoplasmonic nanoplatform combining gold nanorods (GNR) and iron-oxide nanoparticles within phospholipid-based polymeric nanomicelles (PGRFe). The gold nanorods exhibit plasmon resonance absorbance at near infrared wavelengths to enable photoacoustic imaging and photothermal therapy, while the Fe3O4 nanoparticles enable magnetophoretic control of the nanoformulation. The fabricated nanoformulation can be directed and concentrated by an external magnetic field, which provides enhancement of a photoacoustic signal. Application of an external field also leads to enhanced uptake of the magnetoplasmonic formulation by cancer cells in vitro. Under laser irradiation at the wavelength of the GNR absorption peak, the PGRFe formulation efficiently generates plasmonic nanobubbles within cancer cells, as visualized by confocal microscopy, causing cell destruction. The combined magnetic and plasmonic functionalities of the nanoplatform enable magnetic field-directed, imaging-guided, enhanced photo-induced cancer therapy. FROM THE CLINICAL EDITOR: In this study, a nano-formulation of gold nanorods and iron oxide nanoparticles is presented using a phospholipid micelle-based delivery system for magnetic field-directed and imaging-guided photo-induced cancer therapy. The gold nanorods enable photoacoustic imaging and photothermal therapy, while the Fe3O4 nanoparticles enable magnetophoretic control of the formulation. This and similar systems could enable more precise and efficient cancer therapy, hopefully in the near future, after additional testing.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ouro/uso terapêutico , Nanopartículas de Magnetita/administração & dosagem , Nanotubos/análise , Neoplasias/diagnóstico , Neoplasias/terapia , Ouro/administração & dosagem , Ouro/química , Células HeLa , Humanos , Hipertermia Induzida , Campos Magnéticos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Micelas , Nanotubos/ultraestrutura , Fosfolipídeos/química , Técnicas Fotoacústicas , Fototerapia
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