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1.
Adv Mater ; : e2403979, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39044708

RESUMO

The manipulation of cell surface receptors' activity will open a new frontier for drug development and disease treatment. However, limited by the desensitization of drugs, effective physical intervention strategy remains challenging. Here, the controllable internalization of transient receptor potential vanilloid 1 (TRPV1) on neural cells by local piezoelectric field is reported. Single-cell-level local electric field is construct by synthesizing piezoelectric BiOIO3 nanosheets (BIONSs). Upon a mild ultrasound of 0.08 W cm-2, an electric field of 15.29 µV is generated on the surface of BIONSs, further inducing TRPV1 internalization in 5 min. The as-downregulated TRPV1 expression results in the reduction of Ca2+ signal in a spinal neuron and the inhibition of the activity of wide range dynamic neurons, therefore effectively preventing the transmission of cancer-induced bone pain (CIBP). This strategy not only charts a new course for CIBP alleviation, but also introduces a promising nanotechnology for regulating cell surface receptors, showing significant potential in neuropathological and receptor-related diseases.

2.
Nat Nanotechnol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862714

RESUMO

To fulfil the demands of rapid proliferation, tumour cells undergo significant metabolic alterations. Suppression of hyperactivated metabolism has been proven to counteract tumour growth. However, whether the reactivation of downregulated metabolic pathways has therapeutic effects remains unexplored. Here we report a nutrient-based metabolic reactivation strategy for effective melanoma treatment. L-Tyrosine-oleylamine nanomicelles (MTyr-OANPs) were constructed for targeted supplementation of tyrosine to reactivate melanogenesis in melanoma cells. We found that reactivation of melanogenesis using MTyr-OANPs significantly impeded the proliferation of melanoma cells, primarily through the inhibition of glycolysis. Furthermore, leveraging melanin as a natural photothermal reagent for photothermal therapy, we demonstrated the complete eradication of tumours in B16F10 melanoma-bearing mice through treatment with MTyr-OANPs and photothermal therapy. Our strategy for metabolism activation-based tumour treatment suggests specific nutrients as potent activators of metabolic pathways.

3.
Angew Chem Int Ed Engl ; : e202405131, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845566

RESUMO

The limited analgesic efficiency of magnesium restricts its application in pain management. Here, we report boron hydride (BH) with ion currents rectification activity that can enhance the analgesic efficiency of magnesium without the risks of drug tolerance or addiction. We synthesize MgB2, comprising hexagonal boron sheets alternating with Mg2+. In pathological environment, Mg2+ is exchanged by H+, forming two-dimensional borophene-analogue BH sheets. BH interacts with the charged cations via cation-pi interaction, leading to dynamic modulation of sodium and potassium ion currents around neurons. Additionally, released Mg2+ competes Ca2+ to inhibit its influx and neuronal excitation. In vitro cultured dorsal root neurons show a remarkable increase in threshold potential from the normal -35.9 mV to -5.9 mV after the addition of MgB2, indicating potent analgesic effect. In three typical pain models, including CFA-induced inflammatory pain, CINP- or CCI-induced neuropathic pain, MgB2 exhibits analgesic efficiency approximately 2.23, 3.20, and 2.0 times higher than clinical MgSO4, respectively, and even about 1.04, 1.66, and 1.95 times higher than morphine, respectively. The development of magnesium based intermetallic compounds holds promise in addressing the non-opioid medical need for pain relief.

4.
Food Chem X ; 22: 101312, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38559444

RESUMO

Protein glutaminase (PG), originating from Chryseobacterium proteolyticum, can catalyze the deamidation of glutamine residues in plant proteins into glutamic acid, thus enhancing its functional properties. However, the low yield of PG limits its industrial production. In this study, the yield of PG in C. proteolyticum TM1040 increased by 121 %, up to 7.30 U/mL in a 15 L fermenter after medium optimization. Subsequently, purified PG was obtained by cation exchange chromatography (CEX) coupled with hydrophobic interaction chromatography (HIC). The degree of deamidation (DD) of wheat gluten after purified PG deamidation was 87.11 %, which is superior to chemical deamidation in safety and DD. The emulsifying and foaming properties of deamidated wheat gluten were 2.67 and 18.86 times higher, and the water- and oil-holding properties were 4.23 and 18.77 times higher, respectively. The deamidated wheat gluten with enhanced functional properties was used to improve the flavor and texture in baking cakes.

5.
J Am Chem Soc ; 146(13): 9413-9421, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506128

RESUMO

Precise control of cellular signaling events during programmed cell death is crucial yet challenging for cancer therapy. The modulation of signal transduction in cancer cells holds promise but is limited by the lack of efficient, biocompatible, and spatiotemporally controllable approaches. Here we report a photodynamic strategy that modulates both apoptotic and pyroptotic cell death by altering caspase-3 protein activity and the associated signaling crosstalk. This strategy employs a mitochondria-targeting, near-infrared activatable probe (termed M-TOP) that functions via a type-I photochemical mechanism. M-TOP is less dependent on oxygen and more effective in treating drug-resistant cancer cells, even under hypoxic conditions. Our study shows that higher doses of M-TOP induce pyroptotic cell death via the caspase-3/gasdermin-E pathway, whereas lower doses lead to apoptosis. This photodynamic method is effective across diverse gasdermin-E-expressing cancer cells. Moreover, the M-TOP mediated shift from apoptotic to pyroptotic modulation can evoke a controlled inflammatory response, leading to a robust yet balanced immune reaction. This effectively inhibits both distal tumor growth and postsurgical tumor recurrence. This work demonstrates the feasibility of modulating intracellular signaling through the rational design of photodynamic anticancer drugs.


Assuntos
Gasderminas , Neoplasias , Humanos , Caspase 3/metabolismo , Apoptose , Transdução de Sinais , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Caspase 8/metabolismo , Caspase 8/farmacologia , Caspase 1/metabolismo , Caspase 1/farmacologia
6.
Int J Biol Macromol ; 262(Pt 2): 130092, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354920

RESUMO

Protein glutaminase (PG; EC 3.5.1.44) is a novel deamidase that helps to improve functional properties of food proteins. Currently, the highest activated PG enzyme activity was 26 U/mg when recombinantly expressed via the twin-arginine translocation (Tat) pathway in Corynebacterium glutamicum. In this study, superfolder green fluorescent protein (sfGFP) was used to replace traditional signal peptides to facilitate efficient heterologous expression and secretion of Propeptide-Protein glutaminase (PP) in Bacillus subtilis. The fusion protein, sfGFP-PP, was secreted from 12 h of fermentation and reached its highest extracellular expression at 28 h, with a secretion efficiency of about 93 %. Moreover, when fusing sfGFP with PP at the N-terminus, it significantly enhances PG expression up to 26 U/mL by approximately 2.2-fold compared to conventional signal-peptides- guided PP with 11.9 U/mL. Finally, the PG enzyme activity increased from 26 U/mL to 36.9 U/mL after promoter and RBS optimization. This strategy not only provides a new approach to increase PG production as well as extracellular secretion but also offers sfGFP as an effective N-terminal tag for increased secreted production of difficult-to-express proteins.


Assuntos
Bacillus subtilis , Glutaminase , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/química , Glutaminase/genética , Glutaminase/metabolismo , Transporte Proteico , Sinais Direcionadores de Proteínas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
7.
Adv Mater ; 36(2): e2307980, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37823714

RESUMO

Chemodynamic therapy (CDT) is an emerging tumor microenvironment-responsive cancer therapeutic strategy based on Fenton/Fenton-like reactions. However, the effectiveness of CDT is subject to the slow kinetic rate and non-homogeneous distribution of H2 O2 . In this study, a conceptual non-metallic "Fenton-active" center construction strategy is proposed to enhance CDT efficiency using Bi0.44 Ba0.06 Na0.5 TiO2.97 (BNBT-6) nanocrystals. The separated charge carriers under a piezoelectric-induced electric field synchronize the oxidation of H2 O and reduction of H2 O2 , which consequently increases hydroxyl radical (·OH) yield even under low H2 O2 levels. Moreover, acceptor doping induces electron-rich oxygen vacancies to facilitate the dissociation of H2 O2 and H2 O and further promote ·OH generation. In vitro and in vivo experiments demonstrate that BNBT-6 induces extensive intracellular oxidative stress and enhances cell-killing efficiency by activating necroptosis in addition to the conventional apoptotic pathway. This study proposes a novel design approach for nanomaterials used in CDT and presents a new treatment strategy for apoptosis-resistant tumors.


Assuntos
Apoptose , Neoplasias , Humanos , Ultrassonografia , Eletricidade , Elétrons , Radical Hidroxila , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Peróxido de Hidrogênio , Microambiente Tumoral
8.
Adv Sci (Weinh) ; 10(34): e2304668, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870166

RESUMO

Positive computed tomography (CT) contrast nanoagent has significant applications in diagnosing tumors. However, the sensitive differentiation between hepatoma and normal liver tissue remains challenging. This challenge arises primarily because both normal liver and hepatoma tissues capture the nanoagent, resulting in similar positive CT contrasts. Here, a strategy for fusing positive and negative CT contrast nanoagent is proposed to detect hepatoma. A nanoagent Hf-MOF@AB@PVP initially generates a positive CT contrast signal of 120.3 HU in the liver. Subsequently, it can specifically respond to the acidic microenvironment of hepatoma to generate H2 , further achieving a negative contrast of -96.0 HU. More importantly, the relative position between the negative and positive signals area is helpful to determine the location of hepatoma and normal liver tissues. The distinct contrast difference of 216.3 HU and relative orientation between normal liver and tumor tissues are meaningful to sensitively distinguish hepatoma from normal liver tissue utilizing CT imaging.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Microambiente Tumoral
9.
Adv Mater ; 35(18): e2211597, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36746119

RESUMO

The spatiotemporal characterization of signaling crosstalk between subcellular organelles is crucial for the therapeutic effect of malignant tumors. Blocking interactive crosstalk in this fashion is significant but challenging. Herein, a communication interception strategy is reported, which blocks spatiotemporal crosstalk between subcellular organelles for cancer therapy with underlying molecular mechanisms. Briefly, amorphous-core@crystalline-shell Fe@Fe3 O4 nanoparticles (ACFeNPs) are fabricated to specifically block the crosstalk between lysosomes and endoplasmic reticulum (ER) by hydroxyl radicals generated along with their trajectory through heterogeneous Fenton reaction. ACFeNPs initially enter lysosomes and trigger autophagy, then continuous lysosomal damage blocks the generation of functional autolysosomes, which mediates ER-lysosome crosstalk, thus the autophagy is paralyzed. Thereafter, released ACFeNPs from lysosomes induce ER stress. Without the alleviation by autophagy, the ER-stress-associated apoptotic pathway is fully activated, resulting in a remarkable therapeutic effect. This strategy provides a wide venue for nanomedicine to exert biological advantages and confers new perspective for the design of novel anticancer drugs.


Assuntos
Estresse do Retículo Endoplasmático , Neoplasias , Neoplasias/metabolismo , Autofagia , Lisossomos/metabolismo , Humanos
10.
Pharmaceutics ; 14(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36559134

RESUMO

Metal-organic frameworks (MOFs) are crystalline porous materials with periodic network structures formed by self-assembly of metal ions and organic ligands. Attributed to their tunable composition and pore size, ultrahigh surface area (1000-7000 m2/g) and pore volume (1.04-4.40 cm3/g), easy surface modification, appropriate physiological stability, etc., MOFs have been widely used in biomedical applications in the last two decades, especially for the delivery of bioactive agents. In the initial stage, MOFs were widely used to load small molecule drugs with ultra-high doses. Whereafter, more recent work has focused on the load of biomacromolecules, such as nucleic acids and proteins. Over the past years, we have devoted extensive effort to investigate the function of MOF materials for bioactive agent delivery. MOFs can be used not only as an intelligent nanocarrier to deliver or protect bioactive agents but also as an activator for their release or activation in response to the different microenvironments. Altogether, this review details the current progress of MOF materials for bioactive agent delivery and looks into their future development.

11.
Nat Commun ; 13(1): 7353, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446788

RESUMO

Bacteria and excessive inflammation are two main factors causing non-healing wounds. However, current studies have mainly focused on the inhibition of bacteria survival for wound healing while ignoring the excessive inflammation induced by dead bacteria-released lipopolysaccharide (LPS) or peptidoglycan (PGN). Herein, a boron-trapping strategy has been proposed to prevent both infection and excessive inflammation by synthesizing a class of reactive metal boride nanoparticles (MB NPs). Our results show that the MB NPs are gradually hydrolyzed to generate boron dihydroxy groups and metal cations while generating a local alkaline microenvironment. This microenvironment greatly enhances boron dihydroxy groups to trap LPS or PGN through an esterification reaction, which not only enhances metal cation-induced bacterial death but also inhibits dead bacteria-induced excessive inflammation both in vitro and in vivo, finally accelerating wound healing. Taken together, this boron-trapping strategy provides an approach to the treatment of bacterial infection and the accompanying inflammation.


Assuntos
Nanopartículas Metálicas , Infecção dos Ferimentos , Humanos , Peptidoglicano , Lipopolissacarídeos/toxicidade , Boro/farmacologia , Cicatrização , Bactérias , Ligante de CD40 , Inflamação , Compostos de Boro
12.
Angew Chem Int Ed Engl ; 61(45): e202210487, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36117387

RESUMO

T lymphocytes (T cells) are essential for tumor immunotherapy. However, the insufficient number of activated T cells greatly limits the efficacy of tumor immunotherapy. Herein, we proposed an oncolytic virus-mimicking strategy to enhance T cell recruitment and activation for tumor treatment. We constructed an oncolytic virus-like nanoplatform (PolyIC@ZIF-8) that was degraded in the acidic tumor environment to release PolyIC and Zn2+ . The released PolyIC exhibited an oncolytic virus-like function that induced tumor cell apoptosis and promoted T cell recruitment and activation through a tumor antigen-dependent manner. More importantly, the released Zn2+ not only enhanced T cell recruitment by inducing CXCL9/10/11 expression but also promoted T cell activation to increase interferon-γ (INF-γ) expression by inducing the phosphorylation of ZAP-70 via a tumor antigen-independent manner. This Zn2+ -enhanced oncolytic virus-mimicking strategy provides a new approach for tumor immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/metabolismo , Imunoterapia , Neoplasias/terapia , Antígenos de Neoplasias , Linhagem Celular Tumoral
13.
Adv Sci (Weinh) ; 9(23): e2201232, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35712774

RESUMO

In the field of nanomedicine, there is a tendency of matching designed nanomaterials with a suitable type of orthotopic cancer model, not just a casual subcutaneous one. Under this condition, knowing the specific features of the chosen cancer model is the priority, then introducing a proper therapy strategy using designed nanomaterials. Here, the Fenton chemistry is combined with zinc peroxide nanoparticles in the treatment of orthotopic liver cancer which has a "chemical factory" including that liver is the main place for iron storage, metabolism, and also the main metabolic sites for the majority of ingested substances, guaranteeing customized and enhanced chemodynamic therapy and normal liver cells protection as well. The good results in vitro and in vivo can set an inspiring example for exploring and utilizing suitable nanomaterials in corresponding cancer models, ensuring well-fitness of nanomaterials for disease and satisfactory therapeutic effect.


Assuntos
Neoplasias Hepáticas , Nanopartículas , Nanoestruturas , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Nanomedicina/métodos , Fototerapia
14.
ACS Nano ; 16(3): 4217-4227, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35254050

RESUMO

B-mode ultrasound imaging is a significant anatomic technique in clinic, which can display the anatomic variation in tissues. However, it is difficult to evaluate the functional state of organs and display the physiological information in organisms such as the tumor acidic microenvironment (TME). Herein, inspired by the phenomenon of sonographic acoustic shadow during detecting calculus in clinic, a strategy of self-enhanced acoustic impedance difference is proposed to monitor the acidic TME. BiF3@PDA@PEG (BPP) nanoparticles can self-aggregate in a specific response to the acidic TME to form huge "stones" BiF3@PDA, resulting in an increase of local tumor density, and further causing a significant acoustic impedance difference. In in vitro experiments, the enhanced ultrasound signals change from 15.2 to 196.4 dB, which can discriminate different pH values from 7.0 to 5.0, and the sensitivity can reach to 0.2 value. In in vivo experiments, the enhanced ultrasound signal is 107.7 dB after BPP self-aggregated, displaying the weak acidic TME that has a close relationship with the size and species of the tumor. More importantly, the accuracy is away from the interference of pressure because huge "stones" BiF3@PDA change little. However, SonoVue microbubbles will diffuse and rupture under pressure, which results in false positive signals. To sum up, this strategy will be helpful to the further development of ultrasound molecular imaging.


Assuntos
Nanopartículas , Microambiente Tumoral , Acústica , Impedância Elétrica , Microbolhas , Nanopartículas/química
15.
Adv Mater ; 34(17): e2108653, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35244228

RESUMO

The tumor microenvironment is a complex milieu where neurons constitute an important non-neoplastic cell type. From "cancer neuroscience," the crosstalk between tumors and neurons favors the rapid growth of both, making the cancer-nerve interaction a reciprocally beneficial process. Thus, cancer-nerve crosstalk may provide new targets for therapeutic intervention against cancer and cancer-related symptoms. We proposed a nerve-cancer crosstalk blocking strategy for metastatic bone cancer pain treatment, achieved by Mg/Al layered-double-hydroxide nanoshells (Mg/Al-LDH) with AZ-23 loaded inside and alendronate decorated outside. The pain-causing H+ is rapidly eliminated by the LDH, with neurogenesis inhibited by the antagonist AZ-23. As positive feedback, the decreased pain reverses the nerve-to-cancer Ca2+ crosstalk-related cell cycle, dramatically inhibiting tumor growth. All experiments confirm the improved pain threshold and enhanced tumor inhibition. The study may inspire multidisciplinary researchers to focus on cancer-nerve crosstalk for treating cancer and accompanied neuropathic diseases.


Assuntos
Neoplasias Ósseas , Dor do Câncer , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Dor do Câncer/tratamento farmacológico , Dor do Câncer/metabolismo , Humanos , Neurônios/metabolismo , Dor/metabolismo , Microambiente Tumoral
16.
Chem Sci ; 13(8): 2202-2217, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35310479

RESUMO

Redox homeostasis, as an innate cellular defense mechanism, not only contributes to malignant transformation and metastasis of tumors, but also seriously restricts reactive oxygen species (ROS)-mediated tumor therapies, such as chemotherapy, radiotherapy, photodynamic therapy (PDT), and chemodynamic therapy (CDT). Therefore, the development of the redox dyshomeostasis (RDH) strategy based on nanomaterials chemistry is of great significance for developing highly efficient tumor therapy. This review will firstly introduce the basic definition and function of cellular redox homeostasis and RDH. Subsequently, the current representative progress of the nanomaterial-based RDH strategy for tumor therapy is evaluated, summarized and discussed. This strategy can be categorized into three groups: (1) regulation of oxidizing species; (2) regulation of reducing species and (3) regulation of both of them. Furthermore, the current limitations and potential future directions for this field will be briefly discussed. We expect that this review could attract positive attention in the chemistry, materials science, and biomedicine fields and further promote their interdisciplinary integration.

17.
Biomolecules ; 11(9)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34572575

RESUMO

Cell autophagy is a well-known phenomenon in cancer, which limits the efficacy of cancer therapy, especially cancer starvation therapy. Glucose oxidase (GOx), which is considered as an attractive starvation reagent for cancer therapy, can effectively catalyze the conversion of glucose into gluconic acid and hydrogen peroxide (H2O2) in the presence of O2. However, tumor cells adapt to survive by inducing autophagy, limiting the therapy effect. Therefore, anti-cell adaptation via autophagy inhibition could be used as a troubleshooting method to enhance tumor starvation therapy. Herein, we introduce an anti-cell adaptation strategy based on dendritic mesoporous organosilica nanoparticles (DMONs) loaded with GOx and 3-methyladenine (3-MA) (an autophagy inhibition agent) to yield DMON@GOx/3-MA. This formulation can inhibit cell adaptative autophagy after starvation therapy. Our in vitro and in vivo results demonstrate that autophagy inhibition enhances the efficacy of starvation therapy, leading to tumor growth suppression. This anti-cell adaptation strategy will provide a new way to enhance the efficacy of starvation cancer therapy.


Assuntos
Adenina/análogos & derivados , Dendrímeros/química , Glucose Oxidase/metabolismo , Nanopartículas/química , Neoplasias/metabolismo , Neoplasias/terapia , Compostos de Organossilício/química , Adenina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/sangue , Porosidade
18.
Angew Chem Int Ed Engl ; 60(40): 21905-21910, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34322970

RESUMO

In solid tumors, tumor invasion and metastasis account for 90 % of cancer-related deaths. Cell migration is steered by the lamellipodia formed at the leading edge. These lamellipodia can drive the cell body forward by its mechanical deformation regulated by cofilin. Inhibiting cofilin activity can cause significant defects in directional lamellipodia formation and the locomotory capacity of cell invasion, thus contributing to antimetastatic treatment. Herein, a near infrared light (NIR)-controlled nanoscale proton supplier was designed with upconversion nanoparticles (UCNPs) as a core coated in MIL-88B for interior photoacids loading; this photoacids loading can boost H+ transients in cells, which converts the cofilin to an inactive form. Strikingly, inactive cofilin loses the ability to mediate lamellipodia deformation for cell migration. Additionally, the iron, which serves as a catalyticaly active center in MIL-88B, initiates an enhanced Fenton reaction due to the increased H+ in the tumor, ultimately achieving intensive chemodynamic therapy (CDT). This work provides new insight into H+ transients in cells, which not only regulates cofilin protonation for antimetastatic treatment but also improves chemodynamic therapy.


Assuntos
Antineoplásicos/farmacologia , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Fotoquimioterapia , Pseudópodes/efeitos dos fármacos , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raios Infravermelhos , Estruturas Metalorgânicas/química , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Tamanho da Partícula , Propriedades de Superfície
19.
Adv Sci (Weinh) ; 8(11): e2002548, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34105274

RESUMO

Timely detection of liver fibrosis by X-ray computed tomography (CT) can prevent its progression to fatal liver diseases. However, it remains quite challenging because conventional CT can only identify the difference in density instead of X-ray attenuation characteristics. Spectral CT can generate monochromatic imaging to specify X-ray attenuation characteristics of the scanned matter. Herein, an X-ray energy-dependent attenuation strategy originated from bismuth (Bi)-based nanoprobes (BiF3 @PDA@HA) is proposed for the accurate diagnosis of liver fibrosis. Bi element in BiF3 @PDA@HA can exhibit characteristic attenuation depending on different levels of X-ray energy via spectral CT, and that is challenging for conventional CT. In this study, selectively accumulating BiF3 @PDA@HA nanoprobes in the hepatic fibrosis areas can significantly elevate CT value for 40 Hounsfield units on 70 keV monochromatic images, successfully differentiating from healthy livers and achieving the diagnosis of liver fibrosis. Furthermore, the enhancement produced by the BiF3 @PDA@HA nanoprobes in vivo increases as the monochromatic energy decreases from 70 to 40 keV, optimizing the conspicuity of the diseased areas. As a proof of concept, the strategically designed nanoprobes with energy-dependent attenuation characteristics not only expand the scope of CT application, but also hold excellent potential for precise imaging-based disease diagnosis.


Assuntos
Bismuto/farmacologia , Cirrose Hepática/diagnóstico , Nanopartículas/química , Tomografia Computadorizada por Raios X , Animais , Bismuto/química , Meios de Contraste/química , Meios de Contraste/farmacologia , Modelos Animais de Doenças , Humanos , Indóis/química , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Camundongos , Nanopartículas/uso terapêutico , Imagens de Fantasmas , Polímeros/química , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
20.
Front Pharmacol ; 12: 671563, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054544

RESUMO

Lack of vascularization is directly associated with refractory wound healing in diabetes mellitus (DM). Enrichment of endothelial precursor cells (EPCs) is a promising but challenging approach for the treatment of diabetic wounds. Herein, we investigate the action of nicotinamide riboside (NR) on EPC function for improved healing of diabetic wounds. Db/db mice that were treated with NR-supplemented food (400 mg/kg/d) for 12 weeks exhibited higher wound healing rates and angiogenesis than untreated db/db mice. In agreement with this phenotype, NR supplementation significantly increased the number of blood EPCs and bone marrow (BM)-derived EPCs of db/db mice, as well as the tube formation and adhesion functions of BM-EPCs. Furthermore, NR-supplemented BM-EPCs showed higher expression of sirtuin 1 (Sirt1), phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), and lower expression of acetylated peroxisome proliferator-activated receptor γ coactivator (PGC-1α) than BM-EPCs isolated from untreated db/db mice. Knockdown of Sirt1 in BM-EPCs significantly abolished the tube formation and adhesion function of NR as well as the expression of p-AMPK and deacetylated PGC-1a. Inhibition of AMPK abolished the NR-regulated EPC function but had no effect on Sirt1 expression, demonstrating that NR enhances EPC function through the Sirt1-AMPK pathway. Overall, this study demonstrates that the oral uptake of NR enhances the EPC function to promote diabetic wound healing, indicating that NR supplementation might be a promising strategy to prevent the progression of diabetic complications.

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