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1.
Int J Mol Sci ; 25(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38892173

RESUMEN

A-to-I RNA editing, catalyzed by the ADAR protein family, significantly contributes to the diversity and adaptability of mammalian RNA signatures, aligning with developmental and physiological needs. Yet, the functions of many editing sites are still to be defined. The Unc80 gene stands out in this context due to its brain-specific expression and the evolutionary conservation of its codon-altering editing event. The precise biological functions of Unc80 and its editing, however, are still largely undefined. In this study, we first demonstrated that Unc80 editing occurs in an ADAR2-dependent manner and is exclusive to the brain. By employing the CRISPR/Cas9 system to generate Unc80 knock-in mouse models that replicate the natural editing variations, our findings revealed that mice with the "gain-of-editing" variant (Unc80G/G) exhibit heightened basal neuronal activity in critical olfactory regions, compared to the "loss-of-editing" (Unc80S/S) counterparts. Moreover, an increase in glutamate levels was observed in the olfactory bulbs of Unc80G/G mice, indicating altered neurotransmitter dynamics. Behavioral analysis of odor detection revealed distinctive responses to novel odors-both Unc80 deficient (Unc80+/-) and Unc80S/S mice demonstrated prolonged exploration times and heightened dishabituation responses. Further elucidating the olfactory connection of Unc80 editing, transcriptomic analysis of the olfactory bulb identified significant alterations in gene expression that corroborate the behavioral and physiological findings. Collectively, our research advances the understanding of Unc80's neurophysiological functions and the impact of its editing on the olfactory sensory system, shedding light on the intricate molecular underpinnings of olfactory perception and neuronal activity.


Asunto(s)
Adenosina Desaminasa , Percepción Olfatoria , Edición de ARN , Animales , Ratones , Percepción Olfatoria/fisiología , Adenosina Desaminasa/metabolismo , Adenosina Desaminasa/genética , Bulbo Olfatorio/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Neuronas/metabolismo , Sistemas CRISPR-Cas , Masculino , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo
2.
Front Bioeng Biotechnol ; 11: 1272492, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37877039

RESUMEN

Gefitinib (GEF) is an FDA-approved anti-cancer drug for the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC). However, the efficacy of anticancer drugs is limited due to their non-specificity, lower accumulation at target sites, and systemic toxicity. Herein, we successfully synthesized a modified GEF (mGEF) drug and conjugated to Iron oxide nanoparticles (Fe3O4 NPs) for the treatment of NSCLC via magnetic resonance (MR) image-guided drug delivery. A traditional EDC coupling pathway uses mGEF to directly conjugate to Fe3O4 NPs to overcom the drug leakage issues. As a result, we found in vitro drug delivery on mGEF- Fe3O4 NPs exhibits excellent anticancer effects towards the PC9 cells selectively, with an estimated IC 50 value of 2.0 µM. Additionally, in vivo MRI and PET results demonstrate that the NPs could accumulate in tumor-specific regions with localized cell growth inhibition. Results also revealed that outer tumor region exhibiting a stronger contrast than the tinner tumor region which may due necrosis in inner tumor region. In vivo biodistribution further confirms Fe3O4 NPs are more biocompatible and are excreated after the treatment. Overall, we believe that this current strategy of drug modification combined with chemical conjugation on magnetic NPs will lead to improved cancer chemotherapy as well as understanding the tumor microenvironments for better therapeutic outcomes.

3.
Nat Nanotechnol ; 18(12): 1492-1501, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37537274

RESUMEN

Dynamic therapies have potential in cancer treatments but have limitations in efficiency and penetration depth. Here a membrane-integrated liposome (MIL) is created to coat titanium dioxide (TiO2) nanoparticles to enhance electron transfer and increase radical production under low-dose X-ray irradiation. The exoelectrogenic Shewanella oneidensis MR-1 microorganism presents an innate capability for extracellular electron transfer (EET). An EET-mimicking photocatalytic system is created by coating the TiO2 nanoparticles with the MIL, which significantly enhances superoxide anions generation under low-dose (1 Gy) X-ray activation. The c-type cytochromes-constructed electron channel in the membrane mimics electron transfer to surrounding oxygen. Moreover, the hole transport in the valence band is also observed for water oxidation to produce hydroxyl radicals. The TiO2@MIL system is demonstrated against orthotopic liver tumours in vivo.


Asunto(s)
Liposomas , Shewanella , Electrones , Fusión de Membrana , Transporte de Electrón , Oxidación-Reducción
4.
Nat Commun ; 14(1): 4709, 2023 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-37543632

RESUMEN

Chemodynamic therapy (CDT) uses the Fenton or Fenton-like reaction to yield toxic ‧OH following H2O2 → ‧OH for tumoral therapy. Unfortunately, H2O2 is often taken from the limited endogenous supply of H2O2 in cancer cells. A water oxidation CoFe Prussian blue (CFPB) nanoframes is presented to provide sustained, external energy-free self-supply of ‧OH from H2O to process CDT and/or photothermal therapy (PTT). Unexpectedly, the as-prepared CFPB nanocubes with no near-infrared (NIR) absorption is transformed into CFPB nanoframes with NIR absorption due to the increased Fe3+-N ≡ C-Fe2+ composition through the proposed proton-induced metal replacement reactions. Surprisingly, both the CFPB nanocubes and nanoframes provide for the self-supply of O2, H2O2, and ‧OH from H2O, with the nanoframe outperforming in the production of ‧OH. Simulation analysis indicates separated active sites in catalyzation of water oxidation, oxygen reduction, and Fenton-like reactions from CFPB. The liposome-covered CFPB nanoframes prepared for controllable water-driven CDT for male tumoral mice treatments.


Asunto(s)
Nanopartículas , Neoplasias , Masculino , Animales , Ratones , Dominio Catalítico , Peróxido de Hidrógeno , Catálisis , Agua , Línea Celular Tumoral
5.
Biomater Sci ; 11(6): 2177-2185, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36740962

RESUMEN

Biosafety is a critical issue for the successful translocation of nanomaterial-based therapeutic/diagnostic agents from bench to bedside. For instance, after the withdrawal of clinically approved magnetic resonance (MR) imaging contrast agents (CAs) due to their biosafety issues, there is a massive demand for alternative, efficient, and biocompatible MR contrast agents for future MRI clinical applications. To this end, here we successfully demonstrate the in vivo MR contrast abilities and biocompatibilities of ligand-free FeSn2 alloy NPs for tracking in vivo lung tumors. In vitro and in vivo results reveal the FeSn2 alloy NPs acting as appreciable T2 weighted MR contrast agents to locate tumors. The construction of iron (Fe) on biocompatible tin (Sn) greatly facilitates the reduction of the intrinsic toxicities of Fe in vivo resulting in no significant abnormalities in liver and kidney functions. Therefore, we envision that constructing ligand-free alloy NPs will be a promising candidate for tracking in vivo tumors in future clinical applications.


Asunto(s)
Neoplasias Pulmonares , Nanopartículas , Humanos , Medios de Contraste , Imagen por Resonancia Magnética/métodos , Hierro , Neoplasias Pulmonares/diagnóstico por imagen
6.
Diabetologia ; 66(5): 913-930, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36692509

RESUMEN

AIMS/HYPOTHESIS: The mitochondrial chaperonin heat shock protein (HSP) 60 is indispensable in protein folding and the mitochondrial stress response; however, its role in nutrient metabolism remains uncertain. This study investigated the role of HSP60 in diet-induced non-alcoholic fatty liver disease (NAFLD). METHODS: We studied human biopsies from individuals with NAFLD, murine high-fat-diet (HFD; a diet with 60% energy from fat)-induced obesity (DIO), transgenic (Tg) mice overexpressing Hsp60 (Hsp60-Tg), and human HepG2 cells transfected with HSP60 cDNA or with HSP60 siRNA. Histomorphometry was used to assess hepatic steatosis, biochemistry kits were used to measure insulin resistance and glucose tolerance, and an automated home cage phenotyping system was used to assess energy expenditure. Body fat was assessed using MRI. Macrophage infiltration, the lipid oxidation marker 4-hydroxy-2-nonenal (4-HNE) and the oxidative damage marker 8-hydroxy-2'-deoxyguanosine (8-OHdG) were detected using immunohistochemistry. Intracellular lipid droplets were evaluated by Nile red staining. Expression of HSP60, and markers of lipogenesis and fatty acid oxidation were quantified using RT-PCR and immunoblotting. Investigations were analysed using the two-way ANOVA test. RESULTS: Decreased HSP60 expression correlated with severe steatosis in human NAFLD biopsies and murine DIO. Hsp60-Tg mice developed less body fat, had reduced serum triglyceride levels, lower levels of insulin resistance and higher serum adiponectin levels than wild-type mice upon HFD feeding. Respiratory quotient profile indicated that fat in Hsp60-Tg mice may be metabolised to meet energy demands. Hsp60-Tg mice showed amelioration of HFD-mediated hepatic steatosis, M1/M2 macrophage dysregulation, and 4-HNE and 8-OHdG overproduction. Forced HSP60 expression reduced the mitochondrial unfolded protein response, while preserving mitochondrial respiratory complex activity and enhancing fatty acid oxidation. Furthermore, HSP60 knockdown enhanced intracellular lipid formation and loss of sirtuin 3 (SIRT3) signalling in HepG2 cells upon incubation with palmitic acid (PA). Forced HSP60 expression improved SIRT3 signalling and repressed PA-mediated intracellular lipid formation. SIRT3 inhibition compromised HSP60-induced promotion of AMP-activated protein kinase (AMPK) phosphorylation and peroxisome proliferator-activated receptor α (PPARα levels), while also decreasing levels of fatty acid oxidation markers. CONCLUSION/INTERPRETATION: Mitochondrial HSP60 promotes fatty acid oxidation while repressing mitochondrial stress and inflammation to ameliorate the development of NAFLD by preserving SIRT3 signalling. This study reveals the hepatoprotective effects of HSP60 and indicates that HSP60 could play a fundamental role in the development of therapeutics for NAFLD or type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico , Sirtuina 3 , Animales , Humanos , Ratones , Diabetes Mellitus Tipo 2/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos/metabolismo , Resistencia a la Insulina/genética , Metabolismo de los Lípidos , Lípidos , Hígado/metabolismo , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Sirtuina 3/genética , Sirtuina 3/metabolismo
7.
Adv Healthc Mater ; 11(20): e2201613, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35879269

RESUMEN

Photodynamic therapy (PDT) is traditionally ineffective for deeply embedded tumors due to the poor penetration depth of the excitation light. Chemiluminescence resonance energy transfer (CRET) has emerged as a promising mode of PDT without external light. To date, related research has frequently used endogenous hydrogen peroxide (H2 O2 ) and oxygen (O2 ) inside the solid tumor microenvironment to trigger CRET-mediated PDT. Unfortunately, this significantly restricts treatment efficacy and the development of further biomedical applications because of the limited amounts of endogenous H2 O2 and O2 . Herein, a nanohybrid (mSiO2 /CaO2 /CPPO/Ce6: mSCCC) nanoparticle (NP) is designed to achieve synergistic CRET-mediated PDT and calcium (Ca2+ )-overload-mediated therapy. The calcium peroxide (CaO2 ) formed inside mesoporous SiO2 (mSC) with the inclusion of the chemiluminescent agent (CPPO) and photosensitizer (Ce6) self-supplies H2 O2 , O2 , and Ca2+ allowing for the subsequent treatments. The Ce6 in mSCCC NPs is excited by chemical energy in situ following the supply of H2 O2 and O2 to produce singlet oxygen (1 O2 ). The nanohybrid NPs are coated with stearic acid to avoid decomposition during blood circulation through contact with aqueous environment. This nanohybrid shows promising performance in the generation of 1 O2 for external light-free PDT and the release of Ca2+ ions for Ca2+ -overloaded therapy against orthotopic hepatocellular carcinoma.


Asunto(s)
Neoplasias Hepáticas , Nanopartículas , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Calcio , Oxígeno Singlete , Dióxido de Silicio/química , Peróxido de Hidrógeno , Línea Celular Tumoral , Nanopartículas/química , Oxígeno , Neoplasias Hepáticas/tratamiento farmacológico , Nanotecnología , Microambiente Tumoral
8.
Biomater Sci ; 10(18): 5032-5053, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-35858468

RESUMEN

Magnetic resonance imaging (MRI) holds promise for the early clinical diagnosis of various diseases, but most clinical MR techniques require the use of a contrast medium. Several nanomaterial (NM) mediated contrast agents (CAs) are widely used as T1- and T2-based MR contrast agents for clinical and non-clinical applications. Unfortunately, most NM-based CAs are toxic or non-biocompatible, restricting their practical/clinical applications. Therefore, the development of nontoxic and biocompatible CAs for clinical MRI diagnosis is highly desired. To this end, several biocompatible and biomimetic strategies have been developed to offer long blood circulation time, significant biocompatibility, in vivo biodistribution and high contrast ability for efficient imaging. However, detailed review reports on biocompatible NMs, specifically for MR imaging have not yet been summarized. Thus, in the present review we summarize  various surface coating strategies (such as polymers, proteins, cell membranes, etc.) to achieve biocompatible NPs, providing a detailed discussion of advances and future prospects for safe MRI imaging.


Asunto(s)
Medios de Contraste , Nanoestructuras , Imagen por Resonancia Magnética/métodos , Polímeros , Distribución Tisular
9.
Int J Mol Sci ; 23(9)2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35563108

RESUMEN

Neurogenic inflammation and central sensitization play a role in chronic prostatitis/chronic pelvic pain syndrome. We explore the molecular effects of low-intensity shock wave therapy (Li-ESWT) on central sensitization in a capsaicin-induced prostatitis rat model. Male Sprague-Dawley rats underwent intraprostatic capsaicin (10 mM, 0.1 cm3) injections. After injection, the prostate received Li-ESWT twice, one day apart. The L6 dorsal root ganglion (DRG)/spinal cord was harvested for histology and Western blotting on days 3 and 7. The brain blood oxygenation level-dependent (BOLD) functional images were evaluated using 9.4 T fMRI before the Li-ESWT and one day after. Intraprostatic capsaicin injection induced increased NGF-, BDNF-, and COX-2-positive neurons in the L6 DRG and increased COX-2, NGF, BDNF, receptor Trk-A, and TRPV1 protein expression in the L6 DRG and the dorsal horn of the L6 spinal cord, whose effects were significantly downregulated after Li-ESWT on the prostate. Intraprostatic capsaicin injection increased activity of BOLD fMRI responses in brain regions associated with pain-related responses, such as the caudate putamen, periaqueductal gray, and thalamus, whose BOLD signals were reduced after Li-ESWT. These findings suggest a potential mechanism of Li-ESWT on modulation of peripheral and central sensitization for treating CP/CPPS.


Asunto(s)
Tratamiento con Ondas de Choque Extracorpóreas , Prostatitis , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Capsaicina , Ciclooxigenasa 2/metabolismo , Ganglios Espinales/metabolismo , Humanos , Imagen por Resonancia Magnética , Masculino , Factor de Crecimiento Nervioso/metabolismo , Prostatitis/inducido químicamente , Prostatitis/diagnóstico por imagen , Prostatitis/terapia , Ratas , Ratas Sprague-Dawley , Médula Espinal/metabolismo
10.
ACS Appl Mater Interfaces ; 14(11): 13056-13069, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35253424

RESUMEN

Ineffective site-specific delivery has seriously impeded the efficacy of nanoparticle-based drugs to a disease site. Here, we report the preparation of three different shapes (sphere, scroll, and oblate) to systematically evaluate the impact of the marginative delivery on the efficacy of magnetic resonance (MR) imaging-guided X-ray irradiation at a low dose of 1 Gy. In addition to the shape effect, the therapeutic efficacy is investigated for the first time to be strongly related to the structure effect that is associated with the chemical activity. The enhanced particle-vessel wall interaction of both the flat scroll and oblate following margination dynamics leads to greater accumulation in the lungs, resulting in superior performance over the sphere against lung tumor growth and suppression of lung metastasis. Furthermore, the impact of the structural discrepancy in nanoparticles on therapeutic efficacy is considered. The tetragonal oblate reveals that the feasibility of the charge-transfer process outperforms the orthorhombic scroll and cubic sphere to suppress tumors. Finally, surface area is also a crucial factor affecting the efficacy of X-ray treatments from the as-prepared particles.


Asunto(s)
Neoplasias Pulmonares , Nanopartículas , Terapia por Rayos X , Humanos , Pulmón , Neoplasias Pulmonares/diagnóstico por imagen , Imagen por Resonancia Magnética , Nanopartículas/química , Nanopartículas/uso terapéutico
11.
J Nanobiotechnology ; 20(1): 157, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35337331

RESUMEN

BACKGROUND: Late diagnosis of lung cancer is one of the leading causes of higher mortality in lung cancer patients worldwide. Significant research attention has focused on the use of magnetic resonance imaging (MRI) based nano contrast agents to efficiently locate cancer tumors for surgical removal or disease diagnostics. Although contrast agents offer significant advantages, further clinical applications require improvements in biocompatibility, biosafety and efficacy. RESULTS: To address these challenges, we fabricated ultra-fine Iron Carbonate Nanoparticles (FeCO3 NPs) for the first time via modified literature method. Synthesized NPs exhibit ultra-fine size (~ 17 nm), good dispersibility and excellent stability in both aqueous and biological media. We evaluated the MR contrast abilities of FeCO3 NPs and observed remarkable T2 weighted MRI contrast in a concentration dependent manner, with a transverse relaxivity (r2) value of 730.9 ± 4.8 mM-1 S-1at 9.4 T. Moreover, the r2 values of present FeCO3 NPs are respectively 1.95 and 2.3 times higher than the clinically approved contrast agents Resovist® and Friedx at same 9.4 T MR scanner. FeCO3 NPs demonstrate an enhanced T2 weighted contrast for in vivo lung tumors within 5 h of post intravenous administration with no apparent systemic toxicity or induction of inflammation observed in in vivo mice models. CONCLUSION: The excellent biocompatibility and T2 weighted contrast abilities of FeCO3 NPs suggest potential for future clinical use in early diagnosis of lung tumors.


Asunto(s)
Neoplasias Pulmonares , Imagen por Resonancia Magnética , Animales , Medios de Contraste , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Magnetismo , Ratones , Fenómenos Físicos
12.
Biomolecules ; 11(7)2021 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-34356639

RESUMEN

Nanomaterial-mediated cancer therapeutics is a fast developing field and has been utilized in potential clinical applications. However, most effective therapies, such as photodynamic therapy (PDT) and radio therapy (RT), are strongly oxygen-dependent, which hinders their practical applications. Later on, several strategies were developed to overcome tumor hypoxia, such as oxygen carrier nanomaterials and oxygen generated nanomaterials. Among these, oxygen species generation on nanozymes, especially catalase (CAT) mimetic nanozymes, convert endogenous hydrogen peroxide (H2O2) to oxygen (O2) and peroxidase (POD) mimetic nanozymes converts endogenous H2O2 to water (H2O) and reactive oxygen species (ROS) in a hypoxic tumor microenvironment is a fascinating approach. The present review provides a detailed examination of past, present and future perspectives of POD mimetic nanozymes for effective oxygen-dependent cancer phototherapeutics.


Asunto(s)
Nanoestructuras/uso terapéutico , Neoplasias/tratamiento farmacológico , Peroxidasa/química , Fotoquimioterapia/métodos , Animales , Materiales Biomiméticos/farmacología , Humanos , Nanoestructuras/química , Neoplasias/patología , Oxígeno , Peroxidasa/metabolismo , Hipoxia Tumoral , Microambiente Tumoral
13.
Sci Rep ; 11(1): 11406, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34075115

RESUMEN

The stochastic tunnelling-basin hopping-discrete molecular dynamics (STUN-BH-DMD) method was applied to the search for the most stable biomolecular complexes in water by using the MARTINI coarse-grained (CG) model. The epithelial cell adhesion molecule (EpCAM, PDB code: 4MZV) was used as an EpCAM adaptor for an EpA (AptEpA) benchmark target molecule. The effects of two adsorption positions on the EpCAM were analysed, and it is found that the AptEpA adsorption configuration located within the EpCAM pocket-like structure is more stable and the energy barrier is lower due to the interaction with water. By the root mean square deviation (RMSD), the configuration of EpCAM in water is more conservative when the AptEpA binds to EpCAM by attaching to the pocket space of the EpCAM dimer. For AptEpA, the root mean square fluctuation (RMSF) analysis result indicates Nucleobase 1 and Nucleobase 2 display higher flexibility during the CGMD simulation. Finally, from the binding energy contour maps and histogram plots of EpCAM and each AptEpA nucleobase, it is clear that the binding energy adsorbed to the pocket-like structure is more continuous than that energy not adsorbed to the pocket-like structure. This study has proposed a new numerical process for applying the STUN-BH-DMD with the CG model, which can reduce computational details and directly find a more stable AptEpA/EpCAM complex in water.

14.
Sci Rep ; 11(1): 9628, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33953248

RESUMEN

In this simulation work, the linearized Bregman iterative algorithm was applied to solve the magnetic source distribution problem of a magnetic particle imaging (MPI) system for small animals. MPI system can apply an excitation magnetic field, and the induced magnetic field from the magnetic nanoparticles (MNPs) can be detected by the sensors of MPI system. With a gaussian distribution source at the upper side of the mouse brain, sensors set above the mouse brain and the constant excitation magnetic field, the average deviation of the calculated source distribution from the multiplane scanning along the axis away from the mouse brain and the closest plane scanning are 2.78 × 10-3 and 2.84 × 10-3 respectively. The simulated result showed that combination of multiplane scanning hardly improves the accuracy of the source localization. In addition, a gradient scan method was developed that uses gradient magnetic field to scan the mouse brain. The position of the maximum of the lead field matrix will be controlled by the gradient field. With a set up gaussian distribution source at the bottom of the mouse brain, the average deviation of the calculated source distribution from the gradient scan method and the constant field are 4.42 × 10-2 and 5.05 × 10-2. The location error from the two method are 2.24 × 10-1 cm and 3.61 × 10-1 cm. The simulation showed that this method can improve the accuracy compared to constant field when the source is away from the sensor and having a potential for application.

15.
Brain Sci ; 11(4)2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805440

RESUMEN

Imaging evidence for the effect of rehydration on cerebral perfusion and brain ischemia has never been proposed in the literature. This study aimed to test the hypothesis that early rehydration treatment can improve cerebral perfusion and decrease infarct volume, consequently reducing mortality of dehydrated stroke animals. METHODS: Thirty dehydrated experimental rats were randomly assigned to either a rehydration or control group after middle cerebral artery occlusion (MCAO). Diffusion-weighted imaging and dynamic contrast enhancement perfusion imaging were performed at 30 min and 6 h after MCAO using a 9.4T MR imaging scanner to measure the infarct volume and brain perfusion. RESULTS: The survival rates after the first MRI scan were 91.7% for the rehydration group and 58.3% for the control group (p = 0.059). The survival rates after the second MRI scan were 66.7% for the rehydration group, and 8.3% of the control group survived (p = 0.003). The infarct volume of the rehydration group was significantly smaller than control group at 30 min after MCAO (p = 0.007). The delay time and time to maximum were significantly shorter in the rehydration group at 30 min (p = 0.004 and 0.035, respectively). CONCLUSIONS: The findings suggest that early rehydration therapy can decrease the infarct volume, shorten the delay time of cerebral perfusion, and increase survival of dehydrated ischemic-stroke rats. This preliminary study provided imaging evidence that more intensive early hydration therapies and reperfusion strategies may be necessary for acute stroke patients with dehydrated status.

16.
Sci Rep ; 11(1): 1909, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33479331

RESUMEN

Diabetic nephropathy (DN) is one of the major leading cause of kidney failure. To identify the progression of chronic kidney disease (CKD), renal function/fibrosis is playing a crucial role. Unfortunately, lack of sensitivities/specificities of available clinical biomarkers are key major issues for practical healthcare applications to identify the renal functions/fibrosis in the early stage of DN. Thus, there is an emerging approach such as therapeutic or diagnostic are highly desired to conquer the CKD at earlier stages. Herein, we applied and examined the application of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) to identify the progression of fibrosis between wild type (WT) and miR29a transgenic (Tg) mice during streptozotocin (STZ)-induced diabetes. Further, we also validate the potential renoprotective role of miR29a to maintain the renal perfusion, volume, and function. In addition, Ktrans values of DCE-MRI and apparent diffusion coefficient (ADC) of DWI could significantly reflect the level of fibrosis between WT and Tg mice at identical conditions. As a result, we strongly believed that the present non-invasive MR imaging platforms have potential to serveas an important tool in research and clinical imaging for renal fibrosis in diabetes, and that microenvironmental changes could be identified by MR imaging acquisition prior to histological biopsy and diabetic podocyte dysfunction.


Asunto(s)
Nefropatías Diabéticas/diagnóstico por imagen , Fibrosis/diagnóstico por imagen , Riñón/diagnóstico por imagen , MicroARNs/genética , Animales , Biopsia , Medios de Contraste/farmacología , Diabetes Mellitus Experimental/diagnóstico por imagen , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/fisiopatología , Imagen de Difusión por Resonancia Magnética , Progresión de la Enfermedad , Fibrosis/diagnóstico , Fibrosis/genética , Fibrosis/patología , Humanos , Riñón/fisiopatología , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Transgénicos/genética , Persona de Mediana Edad , Podocitos/metabolismo , Podocitos/patología , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/fisiopatología
17.
ACS Appl Bio Mater ; 4(4): 3264-3275, 2021 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35014413

RESUMEN

Combining upconversion nanoparticles (UCNPs) and UV-sensitive polymers to form a smart drug delivery system (DDS) is a promising strategy to circumvent drawbacks of direct UV excitation in clinical applications. This study tuned up core-shell UCNPs with a shell thickness of 6 nm and emission wavelength falling in the ultraviolet region at 350 nm under near-infrared (NIR) light irradiation at 980 nm. An amphiphilic block copolymer with UV-responsive o-nitrobenzyl ester (ONB) next to a glutathione (GSH)-responsive disulfide linkage was synthesized and formulated into a polymersome. Core-shell UCNPs and doxorubicin (DOX) were simultaneously encapsulated into the polymersome during double emulsion for DDS. The combination of NIR light-inducing photolysis of the ONB linkage and GSH cleaving the disulfide linkage enhanced DOX release for chemotherapy. From in vitro evaluation, the polymersome alone was nontoxic against three lung cancer cell lines, but the one loaded with core-shell UCNPs and DOX showed severe cell-killing effect under the assistance of a 980 nm diode laser. In vivo study in A549 tumor-bearing mice verified significant inhibition of tumor growth in mice treated with the polymersome containing core-shell UCNPs and DOX under 980 nm diode laser irradiation as compared with those without laser irradiation and those treated with free DOX. This intriguing nanomedicine of well-defined structures responsive to NIR light and reducing agents offers potential for smart DDS applications.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Materiales Biocompatibles/química , Doxorrubicina/farmacología , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Animales , Antibióticos Antineoplásicos/química , Materiales Biocompatibles/síntesis química , Cápsulas/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Rayos Infrarrojos , Ensayo de Materiales , Ratones , Estructura Molecular , Neoplasias/patología , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Oxidación-Reducción , Tamaño de la Partícula
18.
Int J Nanomedicine ; 15: 8623-8639, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33177822

RESUMEN

BACKGROUND: To improve responses to tumor microenvironments for achieving a better therapeutic outcome in combination cancer therapy, poly(ε-caprolactone)-SS-poly(methacrylic acid) diblock copolymer (PCL-SS-PMAA) with a disulfide linkage between the hydrophobic and hydrophilic junctions was synthesized. MATERIALS AND METHODS: Repeating units of PCL and PMAA in PCL-SS-PMAA were controlled and formulated into polymersomes (PSPps). Truncated octahedral Fe3O4 nanoparticles (IONPs) were synthesized and encapsulated to produce IONPs-PSPps NPs and doxorubicin (DOX) was further loaded to produce IONPs-PSPps@DOX NPs for theranostic applications. RESULTS: IONPs-PSPps NPs remained a superparamagnetic property with a saturation magnetization value of 85 emu⋅gFe3O4 -1 and a relaxivity value of 180 mM-1⋅s-1. Upon exposure to an alternating magnetic field (AMF), IONPs-PSPps NPs increased temperature from 25°C to 54°C within 15 min. Among test groups, the cell apoptosis was greatest in the group exposed to IONPs-PSPps@DOX NPs with AMF and magnet assistance. In vivo T2-weighted magnetic resonance images of A549 tumor-bearing mice also showed highest contrast and greatest tumor suppression in the tumor with AMF and magnet assistance. CONCLUSION: IONPs-PSPps@DOX NPs are a potential theranostic agent having multifaceted applications involving magnetic targeting, MRI diagnosis, hyperthermia and chemotherapy.


Asunto(s)
Doxorrubicina/farmacocinética , Magnetosomas/química , Neoplasias Experimentales/terapia , Nanomedicina Teranóstica/métodos , Células A549 , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacocinética , Apoptosis/efectos de los fármacos , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Humanos , Imagen por Resonancia Magnética , Masculino , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Ratones Endogámicos BALB C , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/patología , Poliésteres/química , Ácidos Polimetacrílicos/química , Microambiente Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Sci Rep ; 10(1): 7600, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32371894

RESUMEN

This research uses molecular dynamics simulation (MD) to study the mechanical properties of pristine polyethylene (PE) and its composites which include silver nanoparticles (PE/AgNPs) at two AgNP weight fractions of 1.05 wt% and 3.10 wt%. The stress-strain distribution of the tensile process shows that the embedded AgNPs can significantly improve the Young's modulus and tensile strength of the pristine PE, due to improvements in the local density and strength of the PE near the AgNP surface in the range of 12 Å. Regarding the effect of temperature on the mechanical properties of pristine PE and PE/AgNP composites, the Young's modulus and the strength of the pristine PE and PE/AgNP composites decreased significantly at 350 K and 450 K, respectively, consistent with predicted melting temperature of pristine PE, which lies at around 360 K. At such temperatures as these, PE material has stronger ductility and a higher mobility of AgNPs in the PE matrix than those at 300 K. With the increase of tensile strain, AgNPs tend to be close, and the fracture of PE leads to a similarity between both the Young's modulus and ultimate strength found for the pristine PE and those found for the PE/AgNP composites at 350 K and 450 K, respectively.

20.
FASEB J ; 34(2): 3267-3288, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31908036

RESUMEN

TIAM2S, the short form of human T-cell lymphoma invasion and metastasis 2, can have oncogenic effects when aberrantly expressed in the liver or lungs. However, it is also abundant in healthy, non-neoplastic brain tissue, in which its primary function is still unknown. Here, we examined the neurobiological and behavioral significance of human TIAM2S using the human brain protein panels, a human NT2/D1-derived neuronal cell line model (NT2/N), and transgenic mice that overexpress human TIAM2S (TIAM2S-TG). Our data reveal that TIAM2S exists primarily in neurons of the restricted brain areas around the limbic system and in well-differentiated NT2/N cells. Functional studies revealed that TIAM2S has no guanine nucleotide exchange factor (GEF) activity and is mainly located in the nucleus. Furthermore, whole-transcriptome and enrichment analysis with total RNA sequencing revealed that TIAM2S-knockdown (TIAM2S-KD) was strongly associated with the cellular processes of the brain structural development and differentiation, serotonin-related signaling, and the diseases markers representing neurobehavioral developmental disorders. Moreover, TIAM2S-KD cells display decreased neurite outgrowth and reduced serotonin levels. Moreover, TIAM2S overexpressing TG mice show increased number and length of serotonergic fibers at early postnatal stage, results in higher serotonin levels at both the serum and brain regions, and higher neuroplasticity and hyperlocomotion in latter adulthood. Taken together, our results illustrate the non-oncogenic functions of human TIAM2S and demonstrate that TIAM2S is a novel regulator of serotonin level, brain neuroplasticity, and locomotion behavior.


Asunto(s)
Encéfalo/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Locomoción , Serotonina/metabolismo , Animales , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Línea Celular Tumoral , Células Cultivadas , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Proyección Neuronal , Plasticidad Neuronal
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