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1.
Pharmaceutics ; 16(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675102

RESUMO

Extracellular vesicles play an important role in intercellular communication, with the potential to serve as biomaterials for nanocarriers. Combining such extracellular vesicles and liposomes results in advanced drug delivery carriers. In this study, we attempted to fabricate hybrid vesicles using a membrane fusion method and incorporated an anticancer drug. As a result, we successfully prepared nanosized uniform hybrid vesicles and evaluated their physicochemical characteristics and intracellular uptake mechanisms via endocytosis in various cell lines. Compared to liposomes, the hybrid vesicles showed better physical properties and a relatively higher reduction in cell viability, which was presumably dependent on the specific cell type. These findings suggest that fusion-based hybrid vesicles offer a novel strategy for delivering therapeutic agents and provide insights into the types of extracellular vesicles that are useful in fabricating hybrid vesicles to develop an advanced drug delivery system.

2.
Int J Biol Macromol ; 267(Pt 2): 131674, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38641285

RESUMO

Polysaccharide CSTPs extracted from Camellia sinensis tea-leaves possessed unique against oxidative damage by scavenging ROS. Herein, acid tea polysaccharide CSTPs-2 with tightly packed molecular structure was isolated, purified and characterized in this research. Furthermore, the effects of CSTPs-2 on ROS-involved inflammatory responses and its underlying mechanisms were investigated. The results suggest that CSTPs-2 dramatically reduced the inflammatory cytokines overexpression and LPS-stimulated cell damage. CSTPs-2 could trigger the dephosphorylation of downstream AKT/MAPK/NF-κB signaling proteins and inhibit nuclear transfer of p-NF-κB to regulate the synthesis and release of inflammatory mediators in LPS-stimulated cells by ROS scavenging. Importantly, the impact of CSTPs-2 in downregulating pro-inflammatory cytokines and mitigating ROS overproduction is associated with clathrin- or caveolae-mediated endocytosis uptake mechanisms, rather than TLR-4 receptor-mediated endocytosis. This study presents a novel perspective for investigating the cellular uptake mechanism of polysaccharides in the context of anti-inflammatory mechanisms.


Assuntos
Camellia sinensis , Endocitose , Inflamação , NF-kappa B , Polissacarídeos , Espécies Reativas de Oxigênio , Transdução de Sinais , Endocitose/efeitos dos fármacos , Camellia sinensis/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Espécies Reativas de Oxigênio/metabolismo , Animais , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Lipopolissacarídeos/farmacologia , Células RAW 264.7 , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Proteínas Proto-Oncogênicas c-akt/metabolismo
3.
Conserv Physiol ; 12(1): coad108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38293640

RESUMO

Concentrations of selenium that exceed regulatory guidelines have been associated with coal mining activities and have been linked to detrimental effects on aquatic ecosystems and the organisms therein. Although the major route of selenium uptake in macroinvertebrates is via the diet, the uptake of waterborne selenite (HSeO3-), the prominent form at circumneutral pH, can be an important contributor to selenium body burden and thus selenium toxicity. In the current study, radiolabelled selenite (Se75) was used to characterize the mechanism of selenite uptake in the water flea, Daphnia magna. The concentration dependence (1-32 µM) of selenite uptake was determined in 1-hour uptake assays in artificial waters that independently varied in bicarbonate, chloride, sulphate, phosphate and selenate concentrations. At concentrations representative of those found in highly contaminated waters, selenite uptake was phosphate-dependent and inhibited by foscarnet, a phosphate transport inhibitor. At higher concentrations, selenite uptake was dependent on waterborne bicarbonate concentration and inhibited by the bicarbonate transporter inhibitor DIDS (4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid). These findings suggest that concentrations of phosphate in coal mining-affected waters could alter selenite uptake in aquatic organisms and could ultimately affect the toxic impacts of selenium in such waters.

4.
Adv Drug Deliv Rev ; 204: 115131, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977338

RESUMO

The cell membrane serves as a barrier against the free entry of foreign substances into the cell. Limited by factors such as solubility and targeting, it is difficult for some drugs to pass through the cell membrane barrier and exert the expected therapeutic effect. Two-dimensional nanomaterial (2D NM) has the advantages of high drug loading capacity, flexible modification, and multimodal combination therapy, making them a novel drug delivery vehicle for drug membrane attachment and intracellular transport. By modulating the surface properties of nanocarriers, it is capable of carrying drugs to break through the cell membrane barrier and achieve precise treatment. In this review, we review the classification of various common 2D NMs, the primary parameters affecting their adhesion to cell membranes, and the uptake mechanisms of intracellular transport. Furthermore, we discuss the therapeutic potential of 2D NMs for several major disorders. We anticipate this review will deepen researchers' understanding of the interaction of 2D NM drug carriers with cell membrane barriers, and provide insights for the subsequent development of novel intelligent nanomaterials capable of intracellular transport.


Assuntos
Nanopartículas , Nanoestruturas , Humanos , Nanoestruturas/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos , Transporte Biológico , Propriedades de Superfície , Nanopartículas/metabolismo
5.
Nanomaterials (Basel) ; 13(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37686976

RESUMO

The increasing release of engineered nanoparticles (NPs) into aquatic ecosystems makes it crucial to understand the interactions of NPs with aquatic organisms, such as algae. In this study, the association of CeO2 NPs with unicellular algae (Raphidocelis subcapitata) and changes to the cellular elemental profile were investigated using three exposure concentrations (1, 50, and 1000 µg CeO2/L) at two different algal growth conditions-exponential and inhibited growth (1% glutaraldehyde). After a 24 h-exposure, algal suspensions were settled by gravity and CeO2-NP/algae association was analyzed by single-cell inductively coupled plasma quadrupole mass spectrometry (sc-ICP-QMS) and ICP time-of-flight MS (sc-ICP-TOFMS). Concurrent detection of the cellular fingerprint with cerium indicated NP association with algae (adsorption/uptake) and changes in the cellular elemental profiles. Less than 5% of cells were associated with NPs when exposed to 1 µg/L. For 50 µg/L exposures in growing and inhibited cell treatments, 4% and 16% of cells were associated with CeO2 NPs, respectively. ICP-TOFMS analysis made it possible to exclude cellular exudates associated with CeO2 NPs due to the cellular fingerprint. Growing and inhibited cells had different elemental profile changes following exposure to CeO2 NPs-e.g., growing cells had higher Mg and lower P contents independent of CeO2 concentration compared to inhibited cells.

6.
Curr Drug Targets ; 24(12): 934-944, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37592775

RESUMO

BACKGROUND: Cancer is a life-threatening disease worldwide, but proper treatment has not yet been developed. Many therapies are available to treat cancer disorders, like chemotherapy, surgery, hormone therapy, and immunotherapy. Chemotherapy often relies on a combination of harmful, highly toxic platinum-based compounds. Also, there are chances of poor distribution of chemotherapeutic agents and cytotoxic to most cells which leads to damage to other healthy cells, also, there are chances of resistance. OBJECTIVE: The main objective of this study is the development of mesoporous silica nanoparticles. Mesoporous silica nanoparticles are recognized as carriers with high drug loading capacity and significant functionalized surface area for targeted drug delivery. Mesoporous silica nanoparticles have shape, particle size, pore volume, higher surface area, and the possibility of surface modification. Hence results in thermally and chemically stable nanomaterials. For targeted drug delivery, MSN is conjugated with a variety of ligands, including monoclonal antibodies, hyaluronic acid, transferrin, folic acid, etc., that have a particular affinity for the receptors that are overexpressed on the surface of malignant cells, so using this nanocarrier reducing the dose related toxicity of normal cell. METHODS: This review focuses on different methods for synthesizing mesoporous silica nanoparticles. Sol-gel method and modified stobber method were used for the synthesis of this nanoparticle. RESULTS: Successfully synthesized mesoporous silica nanoparticle with particle size around 50-200 nm and drug loading efficiency was found to be around 71%. CONCLUSION: Mesoporous silica nanoparticles are great carriers for intracellular and targeted drug delivery systems.

7.
Environ Int ; 179: 108139, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37595535

RESUMO

Pydiflumetofen (PYD), a highly effective and broad-spectrum fungicide, is commonly employed for the control of fungal diseases. In this study, the uptake, translocation, and biotransformation of PYD by wheat (Triticum aestivum L.) were firstly investigated at a chiral level. The findings revealed that the residue concentration of R-PYD in wheat was higher than that of S-PYD, because of its higher uptake rate (k1 = 0.0421 h-1) and lower elimination rate (k2 = 0.0459 h-1). Additionally, R-PYD exhibited higher root bioconcentration factors and translocation factors compared with S-enantiomer, indicating R-PYD was more easily accumulating in roots and translocating to shoots. Furthermore, a total of 9 metabolites, including hydroxylated, demethylated, demethoxylated, dechlorinated, hydrolyzed, and glycosylated-conjugated products, were detected qualitatively in wheat roots or shoots. Symplastic pathway-mediated uptake, which predominantly relied on aquaporins and anion channels, was confirmed by root adsorption and inhibition experiments, without displaying any enantioselective effect. Molecular simulations demonstrated that R-PYD exhibited stronger binding affinity with TaLTP 1.1 with a lower grid score (-6.79 kcal/mol), whereas weaker interaction with the metabolic enzyme (CYP71C6v1) compared to the S-enantiomer. These findings highlight the significance of plant biomacromolecules in the enantioselective bioaccumulation and biotransformation processes. Importantly, a combination of experimental and theoretical evidence provide a comprehensive understanding of the fate of chiral pesticides in plants from an enantioselective perspective.


Assuntos
Triticum , Estereoisomerismo , Transporte Biológico , Biotransformação
8.
Biomedicines ; 11(7)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37509610

RESUMO

Cell-penetrating peptides (CPPs), developed for more than 30 years, are still being extensively studied due to their excellent delivery performance. Compared with other delivery vehicles, CPPs hold promise for delivering different types of drugs. Here, we review the development process of CPPs and summarize the composition and classification of the CPP-based delivery systems, cellular uptake mechanisms, influencing factors, and biological barriers. We also summarize the optimization routes of CPP-based macromolecular drug delivery from stability and targeting perspectives. Strategies for enhanced endosomal escape, which prolong its half-life in blood, improved targeting efficiency and stimuli-responsive design are comprehensively summarized for CPP-based macromolecule delivery. Finally, after concluding the clinical trials of CPP-based drug delivery systems, we extracted the necessary conditions for a successful CPP-based delivery system. This review provides the latest framework for the CPP-based delivery of macromolecular drugs and summarizes the optimized strategies to improve delivery efficiency.

9.
Sci Total Environ ; 898: 165562, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37454835

RESUMO

Historical concentrations of atmospheric mercury (Hg) are uncertain, as monitoring only began a few decades ago. Tree rings can serve as historical archives of Hg, providing centennial trends. The vast majority of tree-ring Hg studies have been published in the last decade, demonstrating the growing use of tree rings for Hg dendrochemistry. Thus, there is a need for a systematic review on current knowledge of tree rings as archives of atmospheric Hg. In this review, the predominant pathways of Hg uptake to tree rings are discussed, including the initial Hg uptake from the surrounding environment, fixation, and subsequent translocation. Foliar uptake of Hg was found to be the most important uptake route for Hg in tree rings, the root and bark route being negligible. Our summary of the suitability of different tree species indicates that radial translocation is the biggest limiting factor for Hg dendrochemistry, shifting and blurring historical Hg trends. Based on the review findings, Picea (spruce) and Larix (larch) are the most promising genera for Hg dendrochemistry. Additionally, the use of tree-ring Hg archives in combination with other co-located archives, namely lake sediments, peat, and ice, is suggested as it enhances the viability of observed tree-ring historical Hg trends. Finally, we propose future directions and recommendations for research using tree-ring Hg, including sampling protocols, experimental designs, and tree selection.


Assuntos
Larix , Mercúrio , Monitoramento Ambiental , Mercúrio/análise , Solo , Projetos de Pesquisa
10.
Environ Pollut ; 331(Pt 2): 121938, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37263566

RESUMO

Per- and polyfluoroalkyl substances (PFAS) have extensively contaminated freshwater aquatic ecosystems where they can be transported in water and partition to sediment and biota. In this paper, three freshwater benthic macroinvertebrates with different foraging modes were exposed to environmentally relevant concentrations of eight perfluoroalkyl carboxylates (PFCA), three perfluoroalkyl sulfonates (PFSA), and three fluorotelomer sulfonates (FTS) at varying divalent cation concentrations of magnesium (Mg2+) and calcium (Ca2+). Divalent cations can impact PFAS partitioning to solids, especially to sediments, at higher concentrations. Sediment dwelling worms (Lumbriculus variegatus), epibenthic grazing snails (Physella acuta), and sediment-dwelling filter-feeding bivalves (Elliptio complanata) were selected due to their unique foraging modes. Microcosms were composed of synthetic sediment, culture water, macroinvertebrates, and PFAS and consisted of a 28-day exposure period. L. variegatus had significantly higher PFAS bioaccumulation than P. acuta and E. complanata, likely due to higher levels of interactions with and ingestion of the contaminated sediment. "High Mg2+" (7.5 mM Mg2+) and "High Ca2+" (7.5 mM Ca2+) conditions generally had statistically higher bioaccumulation factors (BAF) than the "Reference Condition" (0.2 mM Ca2+ and 0.2 mM Mg2+) for PFAS with perfluorinated chain lengths greater than eight carbons. Long-chain PFAS dominated the PFAS profiles of the macroinvertebrates for all groups of compounds studied (PFCA, PFSA, and FTS). These results indicate that the study organism has the greatest impact on bioaccumulation, although divalent cation concentration had observable impacts between organisms depending on the environmental conditions. Elevated cation concentrations in the microcosms led to significantly greater bioaccumulation in the test organisms compared to the experimental reference conditions for long-chain PFAS.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Cátions Bivalentes , Bioacumulação , Ecossistema , Poluentes Químicos da Água/análise , Fluorocarbonos/análise , Água Doce , Alcanossulfonatos , Água , Ácidos Carboxílicos
11.
J Agric Food Chem ; 71(22): 8356-8366, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37219541

RESUMO

Here, we investigated the uptake, transport, and subcellular distribution of the pesticides pymetrozine and spirotetramat, and spirotetramat metabolites B-enol, B-glu, B-mono, and B-keto, under hydroponic conditions. Spirotetramat and pymetrozine exhibited high bioconcentrations in lettuce roots, with both having root concentration factor (RCF) values >1 after exposure for 24 h. The translocation of pymetrozine from roots to shoots was higher than that of spirotetramat. Pymetrozine is absorbed in roots mainly via the symplastic pathway and is primarily stored in the soluble fraction of lettuce root and shoot cells. The cell wall and soluble fractions were the major enrichment sites of spirotetramat and its metabolites in root cells. Spirotetramat and B-enol were mainly enriched in the soluble fractions of lettuce shoot cells, whereas B-keto and B-glu accumulated in cell walls and organelles, respectively. Both symplastic and apoplastic pathways were involved in spirotetramat absorption. Pymetrozine and spirotetramat uptake by lettuce roots was passive, with no aquaporin-mediated dissimilation or diffusion. The findings of this study enhance our understanding of the transfer of pymetrozine, spirotetramat, and spirotetramat metabolites from the environment to lettuce, and their subsequent bioaccumulation. This study describes a novel approach for the efficient management of lettuce pest control using spirotetramat and pymetrozine. At the same time, it is of great significance to evaluate the food safety and environmental risks of spirotetramat and its metabolites.


Assuntos
Lactuca , Praguicidas , Lactuca/metabolismo , Praguicidas/metabolismo , Biotransformação , Raízes de Plantas/metabolismo
12.
Colloids Surf B Biointerfaces ; 227: 113357, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37210795

RESUMO

Functionalized metal oxide nanoparticles (NPs) have demonstrated specific binding affinity to antigens or receptors presented on the cancer cell surface, favouring selective targeting and minimizing side effects during the chemotherapy. Placenta-specific protein 1 (PLAC-1) is a small cell surface protein overexpressed in certain types of breast cancer (BC); therefore, it can be used as a therapeutic target. The objective of this study is to develop NPs that can bind PLAC-1 and hence can inhibit the progression and metastatic potential of BC cells. Zinc oxide (ZnO) NPs were coated with a peptide (GILGFVFTL), which possesses a strong binding ability to PLAC-1. The physical attachment of the peptide to ZnO NPs was verified through various physicochemical and morphological characterization techniques. The selective cytotoxicity of the designed NPs was investigated using PLAC-1-bearing MDA-MB 231 human BC cell line and compared to LS-180 cells that do not express PLAC-1. The anti-metastatic and pro-apoptotic effects of the functionalized NPs on MDA-MB 231 cells were examined. Confocal microscopy was used to investigate the mechanism of NPs uptake by MDA-MB 231 cells. Compared to non-functionalized NPs, peptide functionalization significantly improved the targeting and uptake of the designed NPs by PLAC-1-expressing cancer cells with significant pro-apoptotic and anti-metastatic effects. The uptake of peptide functionalized ZnO NPs (ZnO-P NPs) occurred via peptide-PLAC1 interaction-assisted clathrin-mediated endocytosis. These findings highlight the potential targeted therapy of ZnO-P NPs against PLAC-1-expressing breast cancer cells.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Nanopartículas , Proteínas da Gravidez , Óxido de Zinco , Humanos , Feminino , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/química , Nanopartículas Metálicas/química , Peptídeos/farmacologia
13.
Int J Pharm ; 635: 122753, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36863545

RESUMO

The aim of this study was to evaluate the uptake mechanism of thiolated nanostructured lipid carriers (NLCs). NLCs were decorated with a short-chain polyoxyethylene(10)stearyl ether with a terminal thiol group (NLCs-PEG10-SH) or without (NLCs-PEG10-OH) as well as with a long-chain polyoxyethylene(100)stearyl ether with thiolation (NLCs-PEG100-SH) or without (NLCs-PEG100-OH). NLCs were evaluated for size, polydispersity index (PDI), surface morphology, zeta potential and storage stability over six months. Cytotoxicity, adhesion to the cell surface and internalization of these NLCs in increasing concentrations were evaluated on Caco-2 cells. The influence of NLCs on the paracellular permeability of lucifer yellow was determined. Furthermore, cellular uptake was examined with and without various endocytosis inhibitors as well as reducing and oxidizing agents. NLCs were obtained in a size ranging from 164 to 190 nm, a PDI of 0.2, a negative zeta potential < -33 mV and stability over six months. Cytotoxicity was shown to be concentration dependent and to be lower for NLCs with shorter PEG chains. Permeation of lucifer yellow was 2-fold increased by NLCs-PEG10-SH. All NLCs displayed concentration dependent adhesion to the cell surface and internalization, which was in particular 9.5-fold higher for NLCs-PEG10-SH compared to NLCs-PEG10-OH. Short PEG chain NLCs and especially thiolated short PEG chain NLCs showed higher cellular uptake than NLCs with longer PEG chain. Cellular uptake of all NLCs was mainly clathrin-mediated endocytosis. Thiolated NLCs showed also caveolae-dependent and clathrin- and caveolae-independent uptake. Macropinocytosis was involved in NLCs with long PEG chains. NLCs-PEG10-SH indicated thiol-dependent uptake, which was influenced by reducing and oxidizing agents. Due to thiol groups on the surface of NLCs their cellular uptake and paracellular permeation enhancing properties can be substantially improved.


Assuntos
Nanopartículas , Nanoestruturas , Humanos , Portadores de Fármacos/farmacologia , Células CACO-2 , Lipídeos/farmacologia , Polietilenoglicóis , Tamanho da Partícula
14.
Mol Biotechnol ; 65(9): 1387-1402, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36719639

RESUMO

Novel effective drugs or therapeutic vaccines have been already developed to eradicate viral infections. Some non-viral carriers have been used for effective drug delivery to a target cell or tissue. Among them, cell penetrating peptides (CPPs) attracted a special interest to enhance drug delivery into the cells with low toxicity. They were also applied to transfer peptide/protein-based and nucleic acids-based therapeutic vaccines against viral infections. CPPs-conjugated drugs or vaccines were investigated in several viral infections including poliovirus, Ebola, coronavirus, herpes simplex virus, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, Japanese encephalitis virus, and influenza A virus. Some studies showed that the uptake of CPPs or CPPs-conjugated drugs can be performed through both non-endocytic and endocytic pathways. Despite high potential of CPPs for cargo delivery, there are some serious drawbacks such as non-tissue-specificity, instability, and suboptimal pharmacokinetics features that limit their clinical applications. At present, some solutions are utilized to improve the CPPs properties such as conjugation of CPPs with targeting moieties, the use of fusogenic lipids, generation of the proton sponge effect, etc. Up to now, no CPP or composition containing CPPs has been approved by the Food and Drug Administration (FDA) due to the lack of sufficient in vivo studies on stability, immunological assays, toxicity, and endosomal escape of CPPs. In this review, we briefly describe the properties, uptake mechanisms, advantages and disadvantages, and improvement of intracellular delivery, and bioavailability of cell penetrating peptides. Moreover, we focus on their application as an effective drug carrier to combat viral infections.


Assuntos
Peptídeos Penetradores de Células , Viroses , Humanos , Peptídeos Penetradores de Células/farmacologia , Peptídeos Penetradores de Células/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Proteínas , Viroses/tratamento farmacológico , Viroses/prevenção & controle
15.
Appl Environ Microbiol ; 89(1): e0173222, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36533965

RESUMO

Marine cyanobacteria contribute to approximately half of the ocean primary production, and their biomass is limited by low iron (Fe) bioavailability in many regions of the open seas. The mechanisms by which marine cyanobacteria overcome Fe limitation remain unclear. In this study, multiple Fe uptake pathways have been identified in a coastal strain of Synechococcus sp. strain PCC 7002. A total of 49 mutants were obtained by gene knockout methods, and 10 mutants were found to have significantly decreased growth rates compared to the wild type (WT). The genes related to active Fe transport pathways such as TonB-dependent transporters and the synthesis and secretion of siderophores are found to be essential for the adaptation of Fe limitation in Synechococcus sp. PCC 7002. By comparing the Fe uptake pathways of this coastal strain with other open-ocean cyanobacterial strains, it can be concluded that the Fe uptake strategies from different cyanobacteria have a strong relationship with the Fe bioavailability in their habitats. The evolution and adaptation of cyanobacterial iron acquisition strategies with the change of iron environments from ancient oceans to modern oceans are discussed. This study provides new insights into the diversified strategies of marine cyanobacteria in different habitats from temporal and spatial scales. IMPORTANCE Iron (Fe) is an important limiting factor of marine primary productivity. Cyanobacteria, the oldest photosynthetic oxygen-evolving organisms on the earth, play crucial roles in marine primary productivity, especially in the oligotrophic ocean. How they overcome Fe limitation during the long-term evolution process has not been fully revealed. Fe uptake mechanisms of cyanobacteria have been partially studied in freshwater cyanobacteria but are largely unknown in marine cyanobacterial species. In this paper, the characteristics of Fe uptake mechanisms in a coastal model cyanobacterium, Synechococcus sp. PCC 7002, were studied. Furthermore, the relationship between Fe uptake strategies and Fe environments of cyanobacterial habitats has been revealed from temporal and spatial scales, which provides a good case for marine microorganisms adapting to changes in the marine environment.


Assuntos
Ferro , Synechococcus , Ferro/metabolismo , Synechococcus/genética , Synechococcus/metabolismo , Transporte Biológico , Sideróforos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
16.
Biomed Pharmacother ; 157: 113973, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36413836

RESUMO

Exosomes released from cancer cells are involved in the reorganization of the tumor microenvironment which is the essential aspect of cancer pathogenesis. The intercommunications between cancer cells and diverse cell types in the microenvironment are accomplished by exosomes in ovarian cancer. Internalization pathway, intracellular fate, and biological functions in recipient cells mediated by exosomes released from cisplatin-resistant A2780cis have been studied. Also, histopathological evaluation of tumor, ovary, liver tissues and lymph nodes in vivo studies have been performed. The recipient cells internalized the exosomes via active uptake mechanisms, as shown by confocal microscopy. However, inhibitor studies and flow cytometry analysis showed that each recipient cell line used different uptake pathways. Also, confocal microscopy imaging indicated that the internalized exosomes trapped in the endosomes or phagosomes were distributed to the different cellular compartments including ER, Golgi, and lysosome. The transfer of exosomal oncogenic cargo into the cells modified the intracellular signaling of recipient cells including invasion and metastasis by Boyden-Chamber assay, proliferation by ATP analysis, epithelial-mesenchymal transition (EMT) markers at protein and mRNA levels by western blotting and real-time PCR, and protein kinases in the phospho-kinase array. This remodeling contributed to the initiation of carcinogenesis in ovarian epithelial and peritoneal mesothelial cells, and the progression of carcinogenesis in ovarian cancer cells. In addition, intraperitoneal tumor model studies show that exosomes released from cisplatin-resistant A2780cis cells may play role in the enlargement of lymph nodes, and tumor formations integrated with the liver, attached to the stomach and in the ovarian tissues.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , Cisplatino/farmacologia , Microambiente Tumoral , MicroRNAs/genética , Linhagem Celular Tumoral , Neoplasias Ovarianas/patologia
17.
Microorganisms ; 10(11)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36422309

RESUMO

Electromethanogenesis is an interesting next-generation technology to produce methane from CO2 and electricity by using methanogens. Iron-corroding methanogens might be of special interest for that application due to their natural ability for electron uptake. Methanococcus maripaludis Mic1c10 and KA1 were tested in bioelectrochemical systems. Strain Mic1c10 showed a 120% higher current density and an 84% higher methane production rate (16.2 mmol m-2 d-2) than the non-corrosive strain Methanococcus maripaludis S2, which was identified earlier as the best methane producer under the same experimental conditions. Interestingly, strain KA1 also showed a 265% higher current density than strain S2. Deposits at the cathodes were detected and analyzed, which were not described earlier. A comparative genome analysis between the corrosive methanogen and the S2 strain enables new insights into proteins that are involved in enhanced electron transfer.

18.
Expert Opin Drug Deliv ; 19(12): 1650-1663, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36377494

RESUMO

INTRODUCTION: Ionizable lipids are critical components in lipid nanoparticles. These molecules sequester nucleic acids for delivery to cells. However, to build more efficacious delivery molecules, the field must continue to broaden structure-function studies for greater insight. While nucleic acid-binding efficiency, degradability and nanoparticle stability are vitally important, this review offers perspective on additional factors that must be addressed to improve delivery efficiency. AREAS COVERED: We discuss how administration route, cellular heterogeneity, uptake pathway, endosomal escape timing, age, sex, and threshold effects can change depending on the type of LNP ionizable lipid. EXPERT OPINION: Ionizable lipid structure-function studies often focus on the efficiency of RNA utilization and biodistribution. While these focus areas are critical, they remain high-level observations. As our tools for observation and system interrogation improve, we believe that the field should begin collecting additional data. At the cellular level, this data should include age (dividing or senescent cells), sex and phenotype, cell entry pathway, and endosome type. Additionally, administration route and dose are essential to track. This additional data will allow us to identify and understand heterogeneity in LNP efficacy across patient populations, which will help us provide better ionizable lipid options for different groups.


Assuntos
Nanopartículas , Ácidos Nucleicos , Lipídeos/química , Distribuição Tecidual , Nanopartículas/química , RNA/metabolismo , Endossomos/metabolismo , RNA Interferente Pequeno
19.
Small ; 18(40): e2203207, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057991

RESUMO

Triple ionic and electronic conductivity (TIEC) in cathode materials for protonic ceramic fuel cells (PCFCs) is a desirable feature that enhances the spatial expansion of active reaction sites for electrochemical oxygen reduction reaction. The realization of optimal TIEC in single-phase materials, however, is challenging. A facile route that facilitates the optimization of TIEC in PCFC cathodes is the strategic development of multiphase cathode materials. In this study, a cubic-rhombohedral TIEC nanocomposite material with the composition Ba(CeCo)0.4 (FeZr)0.1 O3- δ (BCCFZ) is designed via self-assembly engineering. The material consists of a mixed ionic and electronic conducting phase, BaCo1-( x + y + z ) Cex Fey Zrz O3- δ (M-BCCFZ), and a dominant proton-conducting phase, BaCe1-( x + y + z ) Cox Zry Fez O3- δ (H-BCCZF). The dominant cerium-rich H-BCCFZ phase enhances the material's oxygen vacancy concentration and the proton defects formation and transport with a low enthalpy of protonation of -30 ± 9 kJ mol-1 . The area-specific resistance of the BCCFZ symmetrical cell is 0.089 Ω cm2 at 650 °C in 2.5% H2 O-air. The peak power density of the anode-supported single cell based on BCCFZ cathode reaches 1054 mW cm-2 at 650 °C with good operation stability spanning over 500 h at 550 °C. These promote BCCFZ as a befitting cathode material geared toward PCFC commercialization.

20.
Int J Biol Macromol ; 196: 144-150, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-34914913

RESUMO

Epigallocatechin-3-gallate (EGCG) has gained appreciable attention because of its health benefits. However, the poor permeability across the intestine limits its use. In this study, we have fabricated chitosan-coated EGCG-hordein nanoparticles (Cs-EHNs), with the aim to enhance the intestinal permeability of EGCG. Cs-EHNs were fabricated by layer-by-layer electrostatic stacking method, and its uptake and transcellular permeability were studied in the Caco-2/HT29 co-culture model. The constructed Cs-EHNs had the average diameter of 296 nm, polymer dispersity index (PDI) of 0.30, zeta potential of 59.6 mV, and showed a spherical morphology. Encapsulation efficiency of EGCG was 87.3%. The transcellular permeability experiments indicated that the apparent permeability coefficient (Papp) of Cs-EHNs was higher than that of free EGCG. Furthermore, the cellular uptake of Cs-EHNs was studied by specific endocytosis inhibitors, and results showed that the uptake mechanisms of Cs-EHNs were through caveolae-mediated endocytosis and macropinocytosis. This study demonstrated that encapsulation of EGCG using chitosan-coated hordein nanoparticles could be a promising approach to improve the absorption of EGCG.


Assuntos
Catequina/análogos & derivados , Quitosana/química , Portadores de Fármacos/química , Glutens/química , Nanopartículas/química , Transporte Biológico , Células CACO-2 , Catequina/química , Linhagem Celular , Células Cultivadas , Humanos , Tamanho da Partícula , Permeabilidade , Análise Espectral
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