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1.
Crit Rev Food Sci Nutr ; : 1-15, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520155

RESUMEN

Microfluidics is revolutionizing the production of microparticles and nanoparticles, offering precise control over dimensions and internal structure. This technology facilitates the creation of colloidal delivery systems capable of encapsulating and releasing nutraceuticals. Nutraceuticals, often derived from food-grade ingredients, can be used for developing functional foods. This review focuses on the principles and applications of microfluidic systems in crafting colloidal delivery systems for nutraceuticals. It explores the foundational principles behind the development of microfluidic devices for nutraceutical encapsulation and delivery. Additionally, it examines the prospects and challenges with using microfluidics for functional food development. Microfluidic systems can be employed to form emulsions, liposomes, microgels and microspheres, by manipulating minute volumes of fluids flowing within microchannels. This versatility can enhance the dispersibility, stability, and bioavailability of nutraceuticals. However, challenges as scaling up production, fabrication complexity, and microchannel clogging hinder the widespread application of microfluidic technologies. In conclusion, this review highlights the potential role of microfluidics in design and fabrication of nutraceutical delivery systems. At present, this technology is most suitable for exploring the role of specific delivery system features (such as particle size, composition and morphology) on the stability and bioavailability of nutraceuticals, rather than for large-scale production of nutraceutical delivery systems.

2.
Nucleic Acids Res ; 47(14): 7690-7702, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31260525

RESUMEN

Bacterial toxin-antitoxin pairs play important roles in bacterial multidrug tolerance. Gcn5-related N-acetyltransferase (GNAT) toxins inhibit translation by acetylation of aminoacyl-tRNAs and are counteracted by direct contacts with cognate ribbon-helix-helix (RHH) antitoxins. Our previous analysis showed that the GNAT toxin KacT and RHH antitoxin KacA of Klebsiella pneumoniae form a heterohexamer in solution and that the complex interacts with the cognate promoter DNA, resulting in negative autoregulation of kacAT transcription. Here, we present the crystal structure of DNA-bound KacAT complex at 2.2 Å resolution. The crystal structure revealed the formation of a unique heterohexamer, KacT-KacA2-KacA2-KacT. The direct interaction of KacA and KacT involves a unique W-shaped structure with the two KacT molecules at opposite ends. Inhibition of KacT is achieved by the binding of four KacA proteins that preclude the formation of an active KacT dimer. The kacAT operon is auto-regulated and we present an experimentally supported molecular model proposing that the KacT:KacA ratio controls kacAT transcription by conditional cooperativity. These results yield a profound understanding of how transcription GNAT-RHH pairs are regulated.


Asunto(s)
Antitoxinas/genética , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Klebsiella pneumoniae/genética , Complejos Multiproteicos/genética , Operón , Antitoxinas/química , Antitoxinas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Cristalografía por Rayos X , Regulación Bacteriana de la Expresión Génica , Klebsiella pneumoniae/metabolismo , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Unión Proteica , Conformación Proteica , Multimerización de Proteína
3.
Biomacromolecules ; 21(3): 1285-1294, 2020 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-32053355

RESUMEN

Tumor angiogenesis with the vascular network formation provides nutrition and oxygen for cancer cells, promoting the proliferation and metastasis of malignant tumors. Bevacizumab (Bev) as an efficient antiangiogenic antibody is able to normalize the tumor vasculature with better blood flow and reduced interstitial fluid pressure, allowing drugs with more uniform distribution and deeper penetration into the tumor; however, it is highly difficult to realize the simultaneous delivery of Bev and anticancer drugs localized at the tumor tissue. Here, we prepared tumor-adhesive and pH-degradable poly(vinyl alcohol) (PVA) microgels for tumor-localized delivery of Bev and docetaxel (DTX), to achieve efficient antiangiogenesis and enhanced cancer chemotherapy. PVA microgels (∼200 µm) decorated with tissue-adhesive dopamine (DA) moieties were fabricated by a combination of high-throughput microfluidics technology and photo-cross-linking chemistry with a considerable coencapsulation efficiency for Bev and DTX. PVA microgels exhibited sustained drug release at the tumoral acidic conditions as the microgel degradation, and DA moieties on the microgels facilitated Bev with long retention at the tumor tissue, highly blocking the vascular endothelial growth factor (VEGF) and inhibiting tumor angiogenesis, as compared to free Bev or no DA-decorated microgels. In addition, the antitumor activity on the 4T1-Luc breast tumor mouse model treated with Bev/DTX-coloaded microgels showed obviously superior tumor growth inhibition than the other treatment groups, in which the combinational therapy efficacy of Bev and DTX mediated by the tumor-adhesive microgels was further confirmed by the immunohistochemistry (IHC) analysis. These PVA microgels with efficient antiangiogenesis and enhanced cancer chemotherapy provide a highly potential platform to treat different malignant tumors as well as the recurrent and metastatic tumors.


Asunto(s)
Microgeles , Neoplasias , Adhesivos , Animales , Concentración de Iones de Hidrógeno , Ratones , Microfluídica , Factor A de Crecimiento Endotelial Vascular
4.
Biomacromolecules ; 21(8): 2966-2982, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32568525

RESUMEN

Small interfering RNAs (siRNAs) have recently emerged as a new class of biopharmaceuticals for the treatment of various diseases, including genetic diseases, viral infections, heritable disorders, and most prominently, cancer. However, clinical applications of siRNA-based therapeutics through intravenous administration have been limited due to their rapid degradation and renal clearance, poor cellular uptake, low cytoplasmic release by escaping endocytic uptake, and off-target effects. The success of siRNA-based therapeutics depends upon the design and creation of efficient delivery vectors that should be able to protect siRNA from in vivo degradation and specifically deliver siRNA to cytosol of target cells. Over the past decade, myriad types of carrier systems composed of cationic polymers have been designed for delivery of siRNA to tumor cells. In this review, we overview recent advances in siRNA delivery by using these promising nonviral carrier systems in diverse approaches to overcome the delivery hindrances and provide valuable understanding to direct the future design of siRNA delivery carriers.


Asunto(s)
Neoplasias , Polímeros , Humanos , Neoplasias/genética , Neoplasias/terapia , ARN Interferente Pequeño/genética
5.
Mol Microbiol ; 108(4): 336-349, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29461656

RESUMEN

A type II toxin-antitoxin (TA) system, in which the toxin contains a Gcn5-related N-acetyltransferase (GNAT) domain, has been characterized recently. GNAT toxin acetylates aminoacyl-tRNA and blocks protein translation. It is abolished by the cognate antitoxin that contains the ribbon-helix-helix (RHH) domain. Here, we present an experimental demonstration of the interaction of the GNAT-RHH complex with TA promoter DNA. First, the GNAT-RHH TA locus kacAT was found in Klebsiella pneumoniae HS11286, a strain resistant to multiple antibiotics. Overexpression of KacT halted cell growth and resulted in persister cell formation. The crystal structure also indicated that KacT is a typical acetyltransferase toxin. Co-expression of KacA neutralized KacT toxicity. Expression of the bicistronic kacAT locus was up-regulated during antibiotic stress. Finally, KacT and KacA formed a heterohexamer that interacted with promoter DNA, resulting in negative autoregulation of kacAT transcription. The N-terminus region of KacA accounted for specific binding to the palindromic sequence on the operator DNA, whereas its C-terminus region was essential for the inactivation of the GNAT toxin. These results provide an important insight into the regulation of the GNAT-RHH family TA system.


Asunto(s)
Acetiltransferasas/química , Acetiltransferasas/metabolismo , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Klebsiella pneumoniae/patogenicidad , Acetiltransferasas/genética , Antibacterianos/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Simulación por Computador , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Sitios Genéticos/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Meropenem/farmacología , Regiones Promotoras Genéticas/genética , Conformación Proteica , Tigeciclina/farmacología , Difracción de Rayos X
6.
Biomacromolecules ; 19(1): 94-102, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29211452

RESUMEN

We investigated the effects of different oxygen tension (21% and 2.5% O2) on the chondrogenesis of different cell systems cultured in pH-degradable PVA hydrogels, including human articular chondrocytes (hACs), human mesenchymal stem cells (hMSCs), and their cocultures with a hAC/hMSC ratio of 20/80. These hydrogels were prepared with vinyl ether acrylate-functionalized PVA (PVA-VEA) and thiolated PVA-VEA (PVA-VEA-SH) via Michael-type addition reaction. The rheology tests determined the gelation of the hydrogels was controlled within 2-7 min, dependent on the polymer concentrations. The different cell systems were cultured in the hydrogel scaffolds for 5 weeks, and the safranin O and GAG assay showed that hypoxia (2.5% O2) greatly promoted the cartilage matrix production with an order of hAC > hAC/hMSC > hMSC. The real time quantitative PCR (RT-PCR) revealed that the hMSC group exhibited the highest hypertrophic marker gene expression (COL10A1, ALPL, MMP13) as well as the dedifferentiated marker gene expression (COL1A1) under normoxia conditions (21% O2), while these expressions were greatly inhibited by coculturing with a 20% amount of hACs and significantly further repressed under hypoxia conditions, which was comparative to the sole hAC group. The enzyme-linked immunosorbent assay (ELISA) also showed that coculture of hMSC/hAC greatly reduced the catabolic gene expression of MMP1 and MMP3 compared with the hMSC group. It is obvious that the hypoxia conditions promoted the chondrogenesis of hMSC by adding a small amount of hACs, and also effectively inhibited their hypotrophy. We are convinced that coculture of hAC/hMSC using in situ forming hydrogel scaffolds is a promising approach to producing cell source for cartilage engineering without the huge needs of primary chondrocyte harvest and expansion.


Asunto(s)
Hipoxia de la Célula , Condrocitos/citología , Condrogénesis , Hidrogeles/química , Células Madre Mesenquimatosas/citología , Andamios del Tejido , Fosfatasa Alcalina/metabolismo , Materiales Biocompatibles/química , Cartílago Articular/citología , Cartílago Articular/enzimología , Cartílago Articular/metabolismo , Condrocitos/enzimología , Condrocitos/metabolismo , Técnicas de Cocultivo , Colágeno/genética , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Glicosaminoglicanos/metabolismo , Humanos , Metaloproteinasa 13 de la Matriz/genética , Células Madre Mesenquimatosas/enzimología , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Fenazinas/metabolismo , Alcohol Polivinílico/química
7.
Mol Cell Proteomics ; 12(5): 1363-76, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23408684

RESUMEN

Bacillus thuringiensis is a well-known entomopathogenic bacterium used worldwide as an environmentally compatible biopesticide. During sporulation, B. thuringiensis accumulates a large number of parasporal crystals consisting of insecticidal crystal proteins (ICPs) that can account for nearly 20-30% of the cell's dry weight. However, the metabolic regulation mechanisms of ICP synthesis remain to be elucidated. In this study, the combined efforts in transcriptomics and proteomics mainly uncovered the following 6 metabolic regulation mechanisms: (1) proteases and the amino acid metabolism (particularly, the branched-chain amino acids) became more active during sporulation; (2) stored poly-ß-hydroxybutyrate and acetoin, together with some low-quality substances provided considerable carbon and energy sources for sporulation and parasporal crystal formation; (3) the pentose phosphate shunt demonstrated an interesting regulation mechanism involving gluconate when CT-43 cells were grown in GYS medium; (4) the tricarboxylic acid cycle was significantly modified during sporulation; (5) an obvious increase in the quantitative levels of enzymes and cytochromes involved in energy production via the electron transport system was observed; (6) most F0F1-ATPase subunits were remarkably up-regulated during sporulation. This study, for the first time, systematically reveals the metabolic regulation mechanisms involved in the supply of amino acids, carbon substances, and energy for B. thuringiensis spore and parasporal crystal formation at both the transcriptional and translational levels.


Asunto(s)
Bacillus thuringiensis/fisiología , Proteínas Bacterianas/genética , Transcriptoma , Acetoína/metabolismo , Proteínas Bacterianas/metabolismo , Ciclo del Ácido Cítrico , Hidroxibutiratos/metabolismo , Anotación de Secuencia Molecular , Fosforilación Oxidativa , Vía de Pentosa Fosfato , Poliésteres/metabolismo , Biosíntesis de Proteínas , Proteoma/genética , Proteoma/metabolismo , Proteómica , ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Esporas Bacterianas/fisiología , Transcripción Genética
8.
Biomater Sci ; 12(12): 3202-3211, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38747944

RESUMEN

Glucose -sensitive delivery systems hold great promise as a therapeutic approach for high-incidence diabetes owing to their ability to release insulin whenever elevated glycemia is detected. However, they are unstable in a hyperglycemic environment, which leads to short-term sustained insulin release. Herein, we designed dually crosslinked insulin polyionic micelles (DCM@insulin) based on triblock polymers of o-glycol and phenylboronic acid-functionalized poly(ethylene glycol)-poly(dimethylamino carbonate)-poly(dimethylamino-trimethylene carbonate) (mPEG-P(AC-co-MPD)-PDMAC and mPEG-P(AC-co-MAPBA)-PDMATC, respectively) for sustained glucose-responsive insulin release. DCM@insulin with a phenylboronic acid ester structure (first crosslinking structure) enhanced glycemic responsiveness by regulating insulin release in a hyperglycemic environment. Additionally, the UV-crosslinking structure (second crosslinking structure) formed by the residual double bonds in AC units endowed DCM@insulin with the ability to effectively protect the loaded insulin against protease degradation and avoid burst release under multiple insulin release. The in vivo findings demonstrated that DCM@insulin effectively maintained glycemic levels (BGLs) within the normal range for 6 h in comparison to single-crosslinked micelles (SCM@insulin). Therefore, the glucose-responsive and dually crosslinked polyionic micelle system exhibits potential as a viable option for the treatment of diabetes.


Asunto(s)
Liberación de Fármacos , Glucosa , Insulina , Micelas , Animales , Ratones , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Ácidos Borónicos/química , Ácidos Borónicos/farmacología , Reactivos de Enlaces Cruzados/química , Preparaciones de Acción Retardada/química , Portadores de Fármacos/química , Glucosa/metabolismo , Glucosa/química , Insulina/metabolismo , Insulina/administración & dosificación , Insulina/química , Polietilenglicoles/química , Masculino , Ratones Endogámicos BALB C
9.
Biomater Sci ; 12(2): 507-517, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38088652

RESUMEN

"Closed-loop" insulin-loaded microneedle patche shows great promise for improving therapeutic outcomes and life quality for diabetes patients. However, it is typically hampered by limited insulin loading capacity, random degradation, and intricate preparation procedures for the independence of the "closed-loop" bulk microneedles. In this study, we combined the solubility of microneedles and "closed-loop" systems and designed poly(vinyl alcohol)-based bulk microneedles (MNs@GI) through in situ photopolymerization for multi-responsive and sustained hypoglycemic therapy, which significantly simplified the preparation process and improved insulin loading. GOx/insulin co-encapsulated MNs@GI with a phenylboronic ester structure improved glycemic responsiveness to control the insulin release under high glucose conditions and reduced inflammation risk in the normal skin. MNs@GI could further degrade to increase insulin release due to the crosslinked acetal-linkage hydrolysis in the presence of gluconic acid, which was caused by GOx-mediated glucose-oxidation in a hyperglycemic environment. The in vivo results showed that MNs@GI effectively regulated glycemic levels within the normal range for approximately 10 h compared to that of only insulin-loaded microneedles (MNs@INS). Consequently, the highly insulin-loaded, multi-responsive, and pH-triggered MN system has tremendous potential for diabetes treatment.


Asunto(s)
Diabetes Mellitus Experimental , Hipoglucemiantes , Animales , Humanos , Hipoglucemiantes/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Insulina/química , Glucosa/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Concentración de Iones de Hidrógeno
10.
Adv Healthc Mater ; 13(7): e2302677, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38245865

RESUMEN

Oral insulin therapies targeting the liver and further simulating close-looped secretion face significant challenges due to multiple trans-epithelial barriers. Herein, ursodeoxycholic acid (UDCA)-decorated zwitterionic nanoparticles (NPs) (UC-CMs@ins) are designed to overcome these barriers, target the liver, and respond to glycemia, thereby achieving oral one-time-per-day therapy. UC-CMs@ins show excellent mucus permeability through the introduction of zwitterion (carboxy betaine, CB). Furthermore, UC-CMs@ins possess superior cellular internalization via proton-assisted amino acid transporter 1 (PAT1, CB-receptor) and apical sodium-dependent bile acid transporter (ASBT, UDCA-receptor) pathways. Moreover, UC-CMs@ins exhibit excellent endolysosomal escape ability and improve the basolateral release of insulin into the bloodstream via the ileal bile acid-binding protein and the heteromeric organic solute transporter (OSTα- OSTß) routes compared with non-UDCA-decorated C-CMs@ins. Therefore, CB and UDCA jointly overcome mucus and intestinal barriers. Additionally, UC-CMs@ins prevent insulin degradation in the gastrointestinal tract for crosslinked structure, improve insulin accumulation in the liver for UDCA introduction, and effectively regulate glycemia for "closed-loop" glucose control. Surprisingly, oral ingestion of UC-CMs@ins shows a superior effect on glycemia (≈22 h, normoglycemia) and improves postprandial glycemic levels in diabetic mice, illustrating the enormous potential of the prepared NPs as a platform for oral insulin administration in diabetes treatment.


Asunto(s)
Diabetes Mellitus Experimental , Nanopartículas , Ratones , Animales , Insulina/uso terapéutico , Ácido Ursodesoxicólico/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Nanopartículas/química , Hígado , Ácidos y Sales Biliares/uso terapéutico , Administración Oral
11.
Acta Biomater ; 182: 288-300, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38729547

RESUMEN

The formation of pre-metastatic niche (PMN) in a hospitable organ derived from the primary tumor requires the communication between the tumor cells and the host environment. Pyruvate is a fundamental nutrient by which the tumor cells metabolically reshape the extracellular matrix in the lung to facilitate their own metastatic development. Here we report a combination regimen by integrating the photo-sensitizer and the mitochondrial pyruvate carrier (MPC) inhibitor in a dendritic polycarbonate core-hyaluronic acid shell nano-platform with multivalent reversible crosslinker embedded in it (DOH-NI+L) to reinforce photodynamic therapy (PDT) toward the primary tumor and interrupt PMN formation in the lung via impeding pyruvate uptake. We show that DOH-NI+L mediates tumor-specific MPC inhibitor liberation, inhibiting the aerobic respiration for facilitated PDT and restraining ATP generation for paralyzing cell invasion. Remarkably, DOH-NI+L is demonstrated to block the metabolic crosstalk of tumor cell-host environment by dampening pyruvate metabolism, provoking a series of metabolic responses and resulting in the pulmonary PMN interruption. Consequently, DOH-NI+L realizes a significant primary tumor inhibition and an efficient pulmonary metastasis prevention. Our research extends nano-based anti-metastatic strategies aiming at PMN intervention and such a dendritic core-shell nano-inhibitor provides an innovative paradigm to inhibit tumor growth and prevent metastasis efficiently. STATEMENT OF SIGNIFICANCE: In the progression of cancer metastasis, the formation of a pre-metastatic niche (PMN) in a hospitable organ derived from the primary tumor is one of the rate-limiting stages. The current nano-based anti-metastatic modalities mainly focus on targeted killing of tumor cells and specific inhibition of tumor cell invasion, while nanomedicine-mediated interruption of PMN formation has been rarely reported. Here we report a combination regimen by integrating a photo-sensitizer and an inhibitor of mitochondrial pyruvate carrier in a dendritic core-shell nano-platform with a reversible crosslinker embedded in it to reinforce PDT toward the primary tumor and interrupt PMN formation via impeding the uptake of pyruvate that is a fundamental nutrient facilitating aerobic respiration and PMN formation. Our research proposed a nano-based anti-metastatic strategy aiming at PMN intervention.


Asunto(s)
Fotoquimioterapia , Ácido Pirúvico , Especies Reactivas de Oxígeno , Fotoquimioterapia/métodos , Animales , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacología , Ratones , Humanos , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Nanopartículas/química , Nanopartículas/uso terapéutico , Ratones Endogámicos BALB C , Femenino , Metástasis de la Neoplasia , Microambiente Tumoral/efectos de los fármacos
12.
J Control Release ; 371: 16-28, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763388

RESUMEN

Metastasis leads to high mortality among cancer patients. It is a complex, multi-step biological process that involves the dissemination of cancer cells from the primary tumor and their systemic spread throughout the body, primarily through the epithelial-mesenchymal transition (EMT) program and immune evasion mechanisms. It presents a challenge in how to comprehensively treat metastatic cancer cells throughout the entire stage of the metastatic cascade using a simple system. Here, we fabricate a nanogel (HNO-NG) by covalently crosslinking a macromolecular nitric oxide (NO) donor with a photothermal IR780 iodide-containing hyaluronic acid derivative via a click reaction. This enables stable storage and tumor-targeted, photothermia-triggered release of NO to combat tumor metastasis throughout all stages. Upon laser irradiation (HNO-NG+L), the surge in NO production within tumor cells impairs the NF-κB/Snail/RKIP signaling loop that promotes the EMT program through S-nitrosylation, thus inhibiting cell dissemination from the primary tumor. On the other hand, it induces immunogenic cell death (ICD) and thereby augments anti-tumor immunity, which is crucial for killing both the primary tumor and systemically distributed tumor cells. Therefore, HNO-NG+L, by fully leveraging EMT reversal, ICD induction, and the lethal effect of NO, achieved impressive eradication of the primary tumor and significant prevention of lung metastasis in a mouse model of orthotropic 4T1 breast tumor that spontaneously metastasizes to the lungs, extending the NO-based therapeutic approach against tumor metastasis.


Asunto(s)
Transición Epitelial-Mesenquimal , Ratones Endogámicos BALB C , Nanogeles , Óxido Nítrico , Animales , Transición Epitelial-Mesenquimal/efectos de los fármacos , Nanogeles/química , Nanogeles/administración & dosificación , Femenino , Línea Celular Tumoral , Metástasis de la Neoplasia/prevención & control , Humanos , Ratones , Ácido Hialurónico/química , Ácido Hialurónico/administración & dosificación , Polietileneimina/química , Polietileneimina/administración & dosificación , Donantes de Óxido Nítrico/administración & dosificación , Donantes de Óxido Nítrico/farmacología , Terapia Fototérmica/métodos , Polietilenglicoles
13.
Adv Healthc Mater ; : e2402556, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39319484

RESUMEN

Despite the potential benefits of close-looped insulin delivery systems in regulating glycemic homeostasis and effectively alleviating diabetes, they still encounter challenges such as limited effectiveness in preventing low glycemic episodes due to sluggish glucose response, and issues with the instability of enzymes and carriers. In this study, dually-crosslinked and glucose oxidase (GOx)-immobilized insulin nanogels (DC-NGs@Ins) are developed for rapid-responsive and sustained hypoglycemic therapy. The DC-NGs@Ins with the phenylborate ester linker enabled the insulin release in a close-looped fashion, and moreover, immobilized GOx-generated hydrogen peroxide (H2O2) by consuming the glucose, which can further bind to phenylborate ester for enhancing glucose response and accelerating the insulin release. The dually-crosslinked structure (phenylboronic ester and UV-crosslinking) effectively minimized the initial burst release of insulin, thus preventing the potential risk of hypoglycemia. More interestingly, GOx immobilized in the nanogels mitigated GOx leakage and enhanced its multiple utilization compared to free GOx. In vivo study demonstrated that DC-NGs@Ins effectively maintained glycemic levels (BGLs) below 200 mg dL-1 for at least 8 h compared to singly-crosslinked nanogels (SC-NGs@Ins). Therefore, this intelligent insulin delivery system shows potential applications in diabetes treatment.

14.
Artículo en Inglés | MEDLINE | ID: mdl-39301793

RESUMEN

In the process of tumor metastasis, tumor cells can acquire invasion by excessive uptake of nutrients and energy and interact with the host microenvironment to shape a premetastatic niche (PMN) that facilitates their colonization and progression in the distal sites. Pyruvate is an essential nutrient that engages in both energy metabolism and remodeling of the extracellular matrix (ECM) in the lungs for PMN formation, thus providing a target for tumor metastasis treatment. There is a paucity of strategies focusing on PMN prevention, which is key to metastasis inhibition. Here, we design a bioresponsive nanoparticle (HP/GU) based on a disulfide-cross-linked hyperbranched polyethylenimine (D-PEI) core and a hyaluronic acid (HA) shell with a reactive oxygen species (ROS)-sensitive cross-linker between them to encapsulate glucose oxidase (GOX) and a mitochondrial pyruvate carrier (MPC) inhibitor via electrostatic interaction, which reinforces starvation therapy and reduces PMN formation in the lungs via inhibiting pyruvate metabolism. In tumor cells, GOX and MPC inhibitors can be rapidly released and synergistically reduce the energy supply of tumor cells by consuming glucose and inhibiting pyruvate uptake to decrease tumor cell invasion. MPC inhibitors can also reduce ECM remodeling by blocking cellular pyruvate metabolism to prevent PMN formation. Consequently, HP/GU achieves an efficient inhibition of both primary and metastatic tumors and provides an innovative strategy for the treatment of tumor metastases.

15.
Artículo en Inglés | MEDLINE | ID: mdl-38461446

RESUMEN

This study proposes a novel inferior vena cava filter (IVCF) design, "Lotus," aiming to enhance release stability and endothelialization. A catheter-filter-vessel model was established for IVCF property analysis, validated by comparing numerical simulations and in vitro tests. Lotus's mechanical properties were analyzed, and optimization suggestions are provided. Compared to existing clinical filters, Lotus demonstrates improved release stability and thrombus capture ability. This work suggests Lotus as a potential technical reference for improved IVCF treatment.

16.
J Proteome Res ; 12(12): 5487-501, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24215520

RESUMEN

Bacillus thuringiensis, a Gram-positive endospore-forming bacterium, is characterized by the formation of parasporal crystals consisting of insecticidal crystal proteins (ICPs) during sporulation. We reveal gene expression profiles and regulatory mechanisms associated with spore and parasporal crystal formation based on transcriptomics and proteomics data of B. thuringiensis strain CT-43. During sporulation, five ICP genes encoded by CT-43 were specifically transcribed; moreover, most of the spore structure-, assembly-, and maturation-associated genes were specifically expressed or significantly up-regulated, with significant characteristics of temporal regulation. These findings suggest that it is essential for the cell to maintain efficient operation of transcriptional and translational machinery during sporulation. Our results indicate that the RNA polymerase complex δ and ω subunits, cold shock proteins, sigma factors, and transcriptional factors as well as the E2 subunit of the pyruvate dehydrogenase complex could cooperatively participate in transcriptional regulation via different mechanisms. In particular, differences in processing and modification of ribosomal proteins, rRNA, and tRNA combined with derepression of translational inhibition could boost the rate of ribosome recycling and assembly as well as translation initiation, elongation, and termination efficiency, thereby compensating for the reduction in ribosomal levels. The efficient operation of translational machineries and powerful protein-quality controlling systems would thus ensure biosyntheses of a large quantity of proteins with normal biological functions during sporulation.


Asunto(s)
Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Biosíntesis de Proteínas , Esporas Bacterianas/genética , Transcripción Genética , Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas y Péptidos de Choque por Frío/genética , Proteínas y Péptidos de Choque por Frío/metabolismo , Cristalización , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Perfilación de la Expresión Génica , Anotación de Secuencia Molecular , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Complejo Piruvato Deshidrogenasa/genética , Complejo Piruvato Deshidrogenasa/metabolismo , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Ribosomas/genética , Ribosomas/metabolismo , Factor sigma/genética , Factor sigma/metabolismo , Esporas Bacterianas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(5): 524-527, 2023 May.
Artículo en Zh | MEDLINE | ID: mdl-37308235

RESUMEN

OBJECTIVE: To observe the correlation between early fluid resuscitation and prognosis in patients with severe acute pancreatitis (SAP). METHODS: SAP patients admitted to the department of critical care medicine of the People's Hospital of Chuxiong Yi Autonomous Prefecture of Yunnan Province from June 2018 to December 2020 were enrolled and analyzed retrospectively. All patients were given the routine treatment according to their condition and relevant diagnostic According to their different prognosis, enrolled patients were divided into death group and survival group. The differences in gender, age, acute physiology and chronic health evaluation II (APACHE II) and Ranson score on admission between the two groups were analyzed. Taking 24 hours as an observation day, the fluid inflow, outflow, and net balance at the first, second, and third 24 hours after admission were recorded, and the ratio of the fluid inflow at the first 24 hours to the total fluid inflow in 72 hours (FV24 h-1 st) was calculated as a study index. Using 33% as the standard, compare the proportion of patients in the two groups who achieved FV24 h-1 st < 33%. The differences of various indicators between the two groups were compared, and the effect of early fluid balance on the prognosis of SAP patients was analyzed. RESULTS: Eighty-nine patients were included in the study (41 in the death group, 48 in the survival group). There were no statistically significant differences on age (years old: 57.6±15.2 vs. 49.5±15.2), gender (male: 61.0% vs. 54.2%), APACHE II score (18.0±2.4 vs. 17.3±2.3), and Ranson score (6.3±1.4 vs. 5.9±1.2) between the death group and the survival group at the time of admission on the intensive care unit (ICU) (all P > 0.05). The fluid intake of the death group in the first 24 hours, the second 24 hours and the third 24 hours after admission to ICU was significantly higher than that of the survival group, and the difference was statistically significant (mL: 4 138±832 vs. 3 535±1 058, 3 883±729 vs. 3 324±516, 3 786±490 vs. 3 212±609, all P < 0.05), and the fluid inflow in the death group at the first 24 hours was greater than 4 100 mL. After treatment, the fluid outflow of the death group at the three 24-hour periods after admission on the ICU was an increasing trend, but it was still significantly less than that of the survival group at the three 24-hour periods (mL: 1 242±465 vs. 1 795±819, 1 536±579 vs. 2 080±524, 1 610±585 vs. 2 932±752, all P < 0.01). Due to the fact that the total fluid inflow and total fluid outflow in the three 24-hour periods in the death group were more than those in the survival group, the net fluid balances in the three 24-hour periods in the death group were still significantly more than those in the survival group finally (mL: 2 896±782 vs. 1 740±725, 2 347±459 vs. 1 243±795, 2 176±807 vs. 338±289, all P < 0.01). There was no difference in FV24 h-1 st between the death group and survival group [FV24 h-1 st > 33%: 56.1% (23/41) vs. 54.2% (26/48), P > 0.05]. CONCLUSIONS: Fluid resuscitation is an important method for early treatment of SAP, but it also has many adverse reactions. Fluid resuscitation indexes such as fluid inflow, outflow, net balance, and FV24 h-1 st within 24 to 72 hours after admission are related to the prognosis of patients with SAP, and can be used as indicators to evaluate the prognosis of SAP. The optimized fluid resuscitation strategy can improve the prognosis of patients with SAP.


Asunto(s)
Pancreatitis , Humanos , Masculino , Enfermedad Aguda , Estudios Retrospectivos , China , Pronóstico , Equilibrio Hidroelectrolítico
18.
Int J Pharm ; 646: 123458, 2023 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-37776964

RESUMEN

Although complexation technique has been documented as a promising strategy to enhance the dissolution rate and bioavailability of water-insoluble drugs, prediction of the enhanced drug solubility related to clathrate compositions and operating conditions is still a challenge. Herein, clathrate compositions (drug content (DC), drug molecular weight (M) and molar ratio (Ratio)), operating conditions (drug concentration (C), pH, pressure (P), temperature (T) and dissolution time (t)) under the different excipients (PEG, PVP, HPMC and cyclodextrin) as main solubilizers of the clathrates condition as input parameters were used to predict two indexes (drug dissolved percentage and dissolution efficiency) simultaneously through machine learning methodfor the first time. The results show that PVP as the main solubilizer of clathrates had higher prediction accuracy to the drug dissolved percentage, and HPMC as the main solubilizer of clathrates had higher prediction accuracy to the drug dissolution efficiency. In addition, the influence of various factors and interactions on the target variables were analyzed. This study affords achievable hints to the quantitative prediction of the drug solubility affected by various compositions and different operating conditions.

19.
J Control Release ; 359: 147-160, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37277053

RESUMEN

Bacteria-infected chronic wound is one of the most serious complications of diabetes and characterized with high morbidity and risk of lower extremity amputation. Nitric oxide (NO) represents a promising strategy to accelerate wound healing through down-regulating inflammation, promoting angiogenesis and bacterial eradication. However, stimuli-responsive and control release of NO at the wound microenvironment remains a challenge. In this work, an injectable, self-healing and antibacterial hydrogel characterized with glucose-responsive and constant NO release behaviors has been engineered for diabetic wound management. The hydrogel (CAHG) is prepared by in situ crosslinking of L-arginine (L-Arg)-coupled chitosan and glucose oxidase (GOx)-modified hyaluronic acid based on Schiff-base reaction. The system is capable of mediating a continuous release of hydrogen peroxide (H2O2) and NO by the cascaded consumption of glucose and L-Arg in the presence of hyperglycemia environment. In vitro studies demonstrate that bacteria proliferation is significantly inhibited by CAHG hydrogel involving in the cascaded release of H2O2 and NO. More importantly, a full-thickness skin wound model on a diabetic mouse demonstrates that H2O2 and NO release from CAHG hydrogel exhibits a superior efficiency for wound healing through bacterial inhibition, down-regulation of pro-inflammatory factors and the elevation of M2-type macrophage, contributing to the collagen deposition and angiogenesis. In conclusion, CAHG hydrogel with excellent biocompatibility and glucose-responsive NO release characteristic can serve as a highly efficient therapeutic strategy for diabetic wound treatment.


Asunto(s)
Diabetes Mellitus , Glucosa , Animales , Ratones , Hidrogeles , Óxido Nítrico , Peróxido de Hidrógeno , Antibacterianos/uso terapéutico , Arginina
20.
J Control Release ; 364: 261-271, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37839641

RESUMEN

Glioblastoma multiforme (GBM) remains incurable in clinical, nanotechnology-based drug delivery strategies show promising perspective in alleviating GBM, while limited blood-brain-barrier (BBB) permeation, short blood half-live accompanied by the poor tumor accumulation and penetration, significantly restrict the therapeutic outcomes. Herein, a versatile super-small zwitterionic nano-system (MCB(S)) based on carboxybetaine (CB) zwitterion functionalized hyperbranched polycarbonate (HPCB) is developed to overcome the brain delivery challenges. After grafting with amino-functionalized IR780 (free IR780), the ultimate paclitaxel (PTX)-encapsulated micelles (MCB(S)-IR@PTX) are precisely activated by near-infrared (NIR) for accelerated drug release and effective combinational GBM therapy. Importantly, MCB(S)-IR@PTX with the crosslinked structure and CB zwitterion prolongs blood-circulation, and CB-zwitterion further facilitates BBB-traversing through betaine/γ-aminobutyric acid (GABA) transporter-1 (BGT-1) pathway. Combined with the benefit of super small-size, MCB(S)-IR@PTX highly accumulates at tumor sites and penetrates deeply, thus efficiently inhibiting tumor growth and strikingly improving survival time in U87MG orthotopic GBM-bearing mouse model. The ingenious nanoplatform furnishes a versatile strategy for delivering therapeutics into the brain and realizing efficient brain cancer therapy.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Ratones , Animales , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Micelas , Barrera Hematoencefálica , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Paclitaxel , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología
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