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2.
Food Res Int ; 186: 114339, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729694

RESUMO

The health-promoting activities of polyphenols and their metabolites originating from germinated quinoa (GQ) are closely related to their digestive behavior, absorption, and colonic fermentation; however, limited knowledge regarding these properties hinder further development. The aim of this study was to provide metabolomic insights into the profile, bioaccessibility, and transepithelial transport of polyphenols from germinated quinoa during in vitro gastrointestinal digestion and Caco-2 cell transport, whilst also investigating the changes in the major polyphenol metabolites and the effects of prebiotics during colonic fermentation. It was found that germination treatment increased the polyphenol content of quinoa by 21.91%. Compared with RQ group, 23 phenolic differential metabolites were upregulated and 47 phenolic differential metabolites were downregulated in GQ group. Compared with RQ group after simulated digestion, 7 kinds of phenolic differential metabolites were upregulated and 17 kinds of phenolic differential metabolites were downregulated in GQ group. Compared with RQ group after cell transport, 7 kinds of phenolic differential metabolites were upregulated and 9 kinds of phenolic differential metabolites were downregulated in GQ group. In addition, GQ improved the bioaccessibilities and transport rates of various polyphenol metabolites. During colonic fermentation, GQ group can also increase the content of SCFAs, reduce pH value, and adjust gut microbial populations by increasing the abundance of Actinobacteria, Bacteroidetes, Verrucomicrobiota, and Spirochaeota at the phylum level, as well as Bifidobacterium, Megamonas, Bifidobacterium, Brevundimonas, and Bacteroides at the genus level. Furthermore, the GQ have significantly inhibited the activity of α-amylase and α-glucosidase. Based on these results, it was possible to elucidate the underlying mechanisms of polyphenol metabolism in GQ and highlight its beneficial effects on the gut microbiota.


Assuntos
Chenopodium quinoa , Colo , Digestão , Fermentação , Metabolômica , Polifenóis , Prebióticos , Humanos , Polifenóis/metabolismo , Chenopodium quinoa/metabolismo , Células CACO-2 , Colo/metabolismo , Colo/microbiologia , Germinação , Transporte Biológico , Disponibilidade Biológica , Microbioma Gastrointestinal/fisiologia
3.
J Plant Res ; 137(3): 293-295, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38700602
4.
Cell Death Dis ; 15(5): 367, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806484

RESUMO

Mitochondria dysfunctions and mitophagy failure have been associated with several Alzheimer's disease (AD) related molecular actors including amyloid beta (Aß) and recently the amyloid precursor protein-C terminal fragments (APP-CTFs). The efficacy of the mitophagy process in neurons relies on regulated mitochondrial transport along axons involving a complex molecular machinery. The contribution of the amyloid precursor protein (APP) and its derived fragments to the mitochondrial transport machinery alterations in AD have not been investigated before. We report herein a change of the expression of mitochondrial transport proteins (SNPH and Miro1), motor adapters (TRANK1 and TRAK2), and components of the dynein and kinesin motors (i.e., IC1,2 and Kif5 (A, B, C) isoforms) by endogenous APP and by overexpression of APP carrying the familial Swedish mutation (APPswe). We show that APP-CTFs and Aß concomitantly regulate the expression of a set of transport proteins as demonstrated in APPswe cells treated with ß- and γ-secretase inhibitors and in cells Knock-down for presenilin 1 and 2. We further report the impact of APP-CTFs on the expression of transport proteins in AAV-injected C99 mice brains. Our data also indicate that both Aß oligomers (Aßo) and APP-CTFs impair the colocalization of mitochondria and transport proteins. This has been demonstrated in differentiated SH-SY5Y naive cells treated with Aßo and in differentiated SH-SY5Y and murine primary neurons expressing APPswe and treated with the γ-secretase inhibitor. Importantly, we uncover that the expression of a set of transport proteins is modulated in a disease-dependent manner in 3xTgAD mice and in human sporadic AD brains. This study highlights molecular mechanisms underlying mitochondrial transport defects in AD that likely contribute to mitophagy failure and disease progression.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Mitocôndrias , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Mitocôndrias/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Peptídeos beta-Amiloides/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Cinesinas/metabolismo , Transporte Biológico , Mitofagia , Proteínas do Tecido Nervoso , Proteínas rho de Ligação ao GTP , Peptídeos e Proteínas de Sinalização Intracelular
5.
Proc Natl Acad Sci U S A ; 121(22): e2313216121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38781209

RESUMO

Plant root systems play a pivotal role in plant physiology and exhibit diverse phenotypic traits. Understanding the genetic mechanisms governing root growth and development in model plants like maize is crucial for enhancing crop resilience to drought and nutrient limitations. This study focused on identifying and characterizing ZmPILS6, an annotated auxin efflux carrier, as a key regulator of various crown root traits in maize. ZmPILS6-modified roots displayed reduced network area and suppressed lateral root formation, which are desirable traits for the "steep, cheap, and deep" ideotype. The research revealed that ZmPILS6 localizes to the endoplasmic reticulum and plays a vital role in controlling the spatial distribution of indole-3-acetic acid (IAA or "auxin") in primary roots. The study also demonstrated that ZmPILS6 can actively efflux IAA when expressed in yeast. Furthermore, the loss of ZmPILS6 resulted in significant proteome remodeling in maize roots, particularly affecting hormone signaling pathways. To identify potential interacting partners of ZmPILS6, a weighted gene coexpression analysis was performed. Altogether, this research contributes to the growing knowledge of essential genetic determinants governing maize root morphogenesis, which is crucial for guiding agricultural improvement strategies.


Assuntos
Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Proteínas de Plantas , Raízes de Plantas , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Morfogênese/genética , Transporte Biológico
6.
Cells ; 13(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38786013

RESUMO

Modern medicine has allowed for many advances in neurological and neurodegenerative disease (ND). However, the number of patients suffering from brain diseases is ever increasing and the treatment of brain diseases remains an issue, as drug efficacy is dramatically reduced due to the existence of the unique vascular structure, namely the blood-brain barrier (BBB). Several approaches to enhance drug delivery to the brain have been investigated but many have proven to be unsuccessful due to limited transport or damage induced in the BBB. Alternative approaches to enhance molecular delivery to the brain have been revealed in recent studies through the existence of molecular delivery pathways that regulate the passage of peripheral molecules. In this review, we present recent advancements of the basic research for these delivery pathways as well as examples of promising ventures to overcome the molecular hurdles that will enhance therapeutic interventions in the brain and potentially save the lives of millions of patients.


Assuntos
Barreira Hematoencefálica , Sistemas de Liberação de Medicamentos , Barreira Hematoencefálica/metabolismo , Humanos , Sistemas de Liberação de Medicamentos/métodos , Animais , Encéfalo/metabolismo , Transporte Biológico
7.
Plant Physiol Biochem ; 211: 108712, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733940

RESUMO

Phosphorus (P), a macronutrient, plays key roles in plant growth, development, and yield. Phosphate (Pi) transporters (PHTs) and PHOSPHATE1 (PHO1) are central to Pi acquisition and distribution. Potentially, PHO1 is also involved in signal transduction under low P. The current study was designed to identify and functionally characterize the PHO1 gene family in chickpea (CaPHO1s). Five CaPHO1 genes were identified through a comprehensive genome-wide search. Phylogenetically, CaPHO1s formed two clades, and protein sequence analyses confirmed the presence of conserved domains. CaPHO1s are expressed in different plant organs including root nodules and are induced by Pi-limiting conditions. Functional complementation of atpho1 mutant with three CaPHO1 members, CaPHO1, CaPHO1;like, and CaPHO1;H1, independently demonstrated their role in root to shoot Pi transport, and their redundant functions. To further validate this, we raised independent RNA-interference (RNAi) lines of CaPHO1, CaPHO1;like, and CaPHO1;H1 along with triple mutant line in chickpea. While single gene RNAi lines behaved just like WT, triple knock-down RNAi lines (capho1/like/h1) showed reduced shoot growth and shoot Pi content. Lastly, we showed that CaPHO1s are involved in root nodule development and Pi content. Our findings suggest that CaPHO1 members function redundantly in root to shoot Pi export and root nodule development in chickpea.


Assuntos
Cicer , Proteínas de Plantas , Nodulação , Cicer/genética , Cicer/metabolismo , Cicer/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nodulação/genética , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Proteínas de Transporte de Fosfato/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Filogenia , Transporte Biológico/genética , Família Multigênica
8.
Elife ; 132024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780415

RESUMO

Stramenopiles form a clade of diverse eukaryotic organisms, including multicellular algae, the fish and plant pathogenic oomycetes, such as the potato blight Phytophthora, and the human intestinal protozoan Blastocystis. In most eukaryotes, glycolysis is a strictly cytosolic metabolic pathway that converts glucose to pyruvate, resulting in the production of NADH and ATP (Adenosine triphosphate). In contrast, stramenopiles have a branched glycolysis in which the enzymes of the pay-off phase are located in both the cytosol and the mitochondrial matrix. Here, we identify a mitochondrial carrier in Blastocystis that can transport glycolytic intermediates, such as dihydroxyacetone phosphate and glyceraldehyde-3-phosphate, across the mitochondrial inner membrane, linking the cytosolic and mitochondrial branches of glycolysis. Comparative analyses with the phylogenetically related human mitochondrial oxoglutarate carrier (SLC25A11) and dicarboxylate carrier (SLC25A10) show that the glycolytic intermediate carrier has lost its ability to transport the canonical substrates malate and oxoglutarate. Blastocystis lacks several key components of oxidative phosphorylation required for the generation of mitochondrial ATP, such as complexes III and IV, ATP synthase, and ADP/ATP carriers. The presence of the glycolytic pay-off phase in the mitochondrial matrix generates ATP, which powers energy-requiring processes, such as macromolecular synthesis, as well as NADH, used by mitochondrial complex I to generate a proton motive force to drive the import of proteins and molecules. Given its unique substrate specificity and central role in carbon and energy metabolism, the carrier for glycolytic intermediates identified here represents a specific drug and pesticide target against stramenopile pathogens, which are of great economic importance.


All living organisms breakdown food molecules to generate energy for processes, such as growing, reproducing and movement. The series of chemical reactions that breakdown sugars into smaller molecules ­ known as glycolysis ­ is so important that it occurs in all life forms, from bacteria to humans. In higher organisms, such as fungi and animals, these reactions take place in the cytosol, the space surrounding the cell's various compartments. A transport protein then shuttles the end-product of glycolysis ­ pyruvate ­ into specialised compartments, known as the mitochondria, where most energy is produced. However, recently it was discovered that a group of living organisms, called the stramenopiles, have a branched glycolysis in which the enzymes involved in the second half of this process are located in both the cytosol and mitochondrial matrix. But it was not known how the intermediate molecules produced after the first half of glycolysis enter the mitochondria. To answer this question, Pyrihová et al. searched for transport protein(s) that could link the two halves of the glycolysis pathway. Computational analyses, comparing the genetic sequences of many transport proteins from several different species, revealed a new group found only in stramenopiles. Pyrihová et al. then used microscopy to visualise these new transport proteins ­ called GIC-1 and GIC-2 ­ in the parasite Blastocystis, which infects the human gut, and observed that they localise to mitochondria. Further biochemical experiments showed that GIC-1 and GIC-2 can physically bind these intermediate molecules, but only GIC-2 can transport them across membranes. Taken together, these observations suggest that GIC-2 links the two halves of glycolysis in Blastocystis. Further analyses could reveal corresponding transport proteins in other stramenopiles, many of which have devastating effects on agriculture, such as Phytophthora, which causes potato blight, or Saprolegnia, which causes skin infections in farmed salmon. Since human cells do not have equivalent transporters, they could be new drug targets not only for Blastocystis, but for these harmful pathogens as well.


Assuntos
Blastocystis , Citosol , Glicólise , Mitocôndrias , Blastocystis/metabolismo , Blastocystis/genética , Humanos , Mitocôndrias/metabolismo , Citosol/metabolismo , Transporte Biológico , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética
9.
Nat Commun ; 15(1): 4036, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740750

RESUMO

Microbial Ni2+ homeostasis underpins the virulence of several clinical pathogens. Ni2+ is an essential cofactor in urease and [NiFe]-hydrogenases involved in colonization and persistence. Many microbes produce metallophores to sequester metals necessary for their metabolism and starve competing neighboring organisms. The fungal metallophore aspergillomarasmine A (AMA) shows narrow specificity for Zn2+, Ni2+, and Co2+. Here, we show that this specificity allows AMA to block the uptake of Ni2+ and attenuate bacterial Ni-dependent enzymes, offering a potential strategy for reducing virulence. Bacterial exposure to AMA perturbs H2 metabolism, ureolysis, struvite crystallization, and biofilm formation and shows efficacy in a Galleria mellonella animal infection model. The inhibition of Ni-dependent enzymes was aided by Zn2+, which complexes with AMA and competes with the native nickelophore for the uptake of Ni2+. Biochemical analyses demonstrated high-affinity binding of AMA-metal complexes to NikA, the periplasmic substrate-binding protein of the Ni2+ uptake system. Structural examination of NikA in complex with Ni-AMA revealed that the coordination geometry of Ni-AMA mimics the native ligand, Ni-(L-His)2, providing a structural basis for binding AMA-metal complexes. Structure-activity relationship studies of AMA identified regions of the molecule that improve NikA affinity and offer potential routes for further developing this compound as an anti-virulence agent.


Assuntos
Proteínas de Bactérias , Níquel , Níquel/metabolismo , Níquel/química , Animais , Virulência/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Zinco/metabolismo , Zinco/química , Mariposas/microbiologia , Urease/metabolismo , Urease/antagonistas & inibidores , Transporte Biológico
10.
AAPS PharmSciTech ; 25(5): 113, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750336

RESUMO

Transport of oral nanocarriers across the GI epithelium necessitates transport across hydrophilic mucus layer and the hydrophobic epithelium. Based on hydrophobic-hydrophilic balance, Curcumin-Lipomer (lipid-polymer hybrid nanoparticles) comprising hydrophobic stearic acid and hydrophilic Gantrez™ AN 119 (Gantrez) were developed, by a radical in-situ approach, to successfully traverse both barriers. A monophasic preconcentrate (Cur-Pre) comprising Cur (Curcumin), stearic acid, Gantrez and stabilizers, prepared by simple solution, was added to an aqueous phase to instantaneously generate Curcumin-Lipomer (Cur-Lipo) of nanosize and high entrapment efficiency (EE). Cur-Lipo size and EE was optimized by Box-Behnken Design. Cur-Lipomers of varying hydrophobic-hydrophilic property obtained by varying the stearic acid: Gantrez ratio exhibited size in the range 200-400 nm, EE > 95% and spherical morphology as seen in the TEM. A decrease in contact angle and in mucus interaction, evident with increase in Gantrez concentration, indicated an inverse corelation with hydrophilicity, while a linear corelation was observed for mucopenetration and hydrophilicity. Cur-SLN (solid lipid nanoparticles) which served as the hydrophobic reference revealed contact angle > 90°, maximum interaction with mucus and minimal mucopenetration. The ex-vivo permeation study through chicken ileum, revealed maximum permeation with Cur-Lipo1 and comparable and significantly lower permeation of Cur-Lipo1-D and Cur-SLN proposing the importance of balancing the hydrophobic-hydrophilic property of the nanoparticles. A 1.78-fold enhancement in flux of hydrophobic Cur-SLN, with no significant change in permeation of the hydrophilic Cur-Lipomers (p > 0.05) following stripping off the mucosal layer was observed. This reiterated the significance of hydrophobic-hydrophilic balance as a promising strategy to design nanoformulations with superior permeation across the GI barrier.


Assuntos
Curcumina , Portadores de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Mucosa Intestinal , Nanopartículas , Ácidos Esteáricos , Nanopartículas/química , Administração Oral , Animais , Ácidos Esteáricos/química , Curcumina/administração & dosagem , Curcumina/farmacocinética , Curcumina/química , Mucosa Intestinal/metabolismo , Portadores de Fármacos/química , Tamanho da Partícula , Lipídeos/química , Polímeros/química , Transporte Biológico/fisiologia , Polivinil/química
11.
Mol Cell ; 84(10): 1932-1947.e10, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38703769

RESUMO

Mutations in transporters can impact an individual's response to drugs and cause many diseases. Few variants in transporters have been evaluated for their functional impact. Here, we combine saturation mutagenesis and multi-phenotypic screening to dissect the impact of 11,213 missense single-amino-acid deletions, and synonymous variants across the 554 residues of OCT1, a key liver xenobiotic transporter. By quantifying in parallel expression and substrate uptake, we find that most variants exert their primary effect on protein abundance, a phenotype not commonly measured alongside function. Using our mutagenesis results combined with structure prediction and molecular dynamic simulations, we develop accurate structure-function models of the entire transport cycle, providing biophysical characterization of all known and possible human OCT1 polymorphisms. This work provides a complete functional map of OCT1 variants along with a framework for integrating functional genomics, biophysical modeling, and human genetics to predict variant effects on disease and drug efficacy.


Assuntos
Simulação de Dinâmica Molecular , Humanos , Células HEK293 , Relação Estrutura-Atividade , Mutação de Sentido Incorreto , Farmacogenética , Fenótipo , Transportador 1 de Cátions Orgânicos/genética , Transportador 1 de Cátions Orgânicos/metabolismo , Mutação , Conformação Proteica , Transporte Biológico , Fator 1 de Transcrição de Octâmero
12.
PLoS One ; 19(5): e0299160, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748761

RESUMO

Microphysiological models (MPS) are increasingly getting recognized as in vitro preclinical systems of pathophysiology and drug discovery. However, there is also a growing need to adapt and advance MPS to include the physiological contributions of the capillary vascular dynamics, because they undergo angiogenesis or vasculogenesis to deliver soluble oxygen and nutrients to its organs. Currently, the process of formation of microvessels in MPS is measured arbitrarily, and vascularized MPS do not include oxygen measurements in their analysis. Sensing and measuring tissue oxygen delivery is extremely difficult because it requires access to opaque and deep tissue, and/or requires extensive integration of biosensors that makes such systems impractical to use in the real world. Here, a finite element method-based oxygen transport program, called AngioMT, is built in MATLAB. AngioMT processes the routinely acquired 2D confocal images of microvascular networks in vitro and solves physical equations of diffusion-reaction dominated oxygen transport phenomena. This user-friendly image-to-physics transition in AngioMT is an enabling tool of MPS analysis because unlike the averaged morphological measures of vessels, it provides information of the spatial transport of oxygen both within the microvessels and the surrounding tissue regions. Further, it solves the more complex higher order reaction mechanisms which also improve the physiological relevance of this tool when compared directly against in vivo measurements. Finally, the program is applied in a multicellular vascularized MPS by including the ability to define additional organ/tissue subtypes in complex co-cultured systems. Therefore, AngioMT serves as an analytical tool to enhance the predictive power and performance of MPS that incorporate microcirculation.


Assuntos
Oxigênio , Oxigênio/metabolismo , Humanos , Animais , Transporte Biológico , Neovascularização Fisiológica , Microvasos/metabolismo , Microvasos/diagnóstico por imagem , Microcirculação , Modelos Biológicos , Sistemas Microfisiológicos
13.
Nat Commun ; 15(1): 3985, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734677

RESUMO

Pentamidine and melarsoprol are primary drugs used to treat the lethal human sleeping sickness caused by the parasite Trypanosoma brucei. Cross-resistance to these two drugs has recently been linked to aquaglyceroporin 2 of the trypanosome (TbAQP2). TbAQP2 is the first member of the aquaporin family described as capable of drug transport; however, the underlying mechanism remains unclear. Here, we present cryo-electron microscopy structures of TbAQP2 bound to pentamidine or melarsoprol. Our structural studies, together with the molecular dynamic simulations, reveal the mechanisms shaping substrate specificity and drug permeation. Multiple amino acids in TbAQP2, near the extracellular entrance and inside the pore, create an expanded conducting tunnel, sterically and energetically allowing the permeation of pentamidine and melarsoprol. Our study elucidates the mechanism of drug transport by TbAQP2, providing valuable insights to inform the design of drugs against trypanosomiasis.


Assuntos
Aquagliceroporinas , Microscopia Crioeletrônica , Melarsoprol , Simulação de Dinâmica Molecular , Pentamidina , Trypanosoma brucei brucei , Trypanosoma brucei brucei/metabolismo , Aquagliceroporinas/metabolismo , Aquagliceroporinas/química , Melarsoprol/metabolismo , Melarsoprol/química , Pentamidina/química , Pentamidina/metabolismo , Transporte Biológico , Tripanossomicidas/química , Tripanossomicidas/metabolismo , Tripanossomicidas/farmacologia , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Humanos
14.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731891

RESUMO

The past five decades have witnessed remarkable advancements in the field of inhaled medicines targeting the lungs for respiratory disease treatment. As a non-invasive drug delivery route, inhalation therapy offers numerous benefits to respiratory patients, including rapid and targeted exposure at specific sites, quick onset of action, bypassing first-pass metabolism, and beyond. Understanding the characteristics of pulmonary drug transporters and metabolizing enzymes is crucial for comprehending efficient drug exposure and clearance processes within the lungs. These processes are intricately linked to both local and systemic pharmacokinetics and pharmacodynamics of drugs. This review aims to provide a comprehensive overview of the literature on lung transporters and metabolizing enzymes while exploring their roles in exogenous and endogenous substance disposition. Additionally, we identify and discuss the principal challenges in this area of research, providing a foundation for future investigations aimed at optimizing inhaled drug administration. Moving forward, it is imperative that future research endeavors to focus on refining and validating in vitro and ex vivo models to more accurately mimic the human respiratory system. Such advancements will enhance our understanding of drug processing in different pathological states and facilitate the discovery of novel approaches for investigating lung-specific drug transporters and metabolizing enzymes. This deeper insight will be crucial in developing more effective and targeted therapies for respiratory diseases, ultimately leading to improved patient outcomes.


Assuntos
Pulmão , Proteínas de Membrana Transportadoras , Humanos , Administração por Inalação , Pulmão/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Animais , Preparações Farmacêuticas/metabolismo , Preparações Farmacêuticas/administração & dosagem , Transporte Biológico
15.
Int J Mol Sci ; 25(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38732233

RESUMO

Donepezil (DNPZ) is a cholinesterase inhibitor used for the management of Alzheimer's disease (AD) and is dependent on membrane transporters such as ABCG2 to actively cross brain barriers and reach its target site of action in the brain. Located in the brain ventricles, the choroid plexus (CP) forms an interface between the cerebrospinal fluid (CSF) and the bloodstream, known as the blood-CSF barrier (BCSFB). Historically, the BCSFB has received little attention as a potential pathway for drug delivery to the central nervous system (CNS). Nonetheless, this barrier is presently viewed as a dynamic transport interface that limits the traffic of molecules into and out of the CNS through the presence of membrane transporters, with parallel activity with the BBB. The localization and expression of drug transporters in brain barriers represent a huge obstacle for drug delivery to the brain and a major challenge for the development of therapeutic approaches to CNS disorders. The widespread interest in understanding how circadian clocks modulate many processes that define drug delivery in order to predict the variability in drug safety and efficacy is the next bridge to improve effective treatment. In this context, this study aims at characterizing the circadian expression of ABCG2 and DNPZ circadian transport profile using an in vitro model of the BCSFB. We found that ABCG2 displays a circadian pattern and DNPZ is transported in a circadian way across this barrier. This study will strongly impact on the capacity to modulate the BCSFB in order to control the penetration of DNPZ into the brain and improve therapeutic strategies for the treatment of AD according to the time of the day.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Barreira Hematoencefálica , Donepezila , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Barreira Hematoencefálica/metabolismo , Animais , Humanos , Encéfalo/metabolismo , Inibidores da Colinesterase/farmacocinética , Inibidores da Colinesterase/farmacologia , Transporte Biológico , Plexo Corióideo/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Camundongos , Ritmo Circadiano , Proteínas de Neoplasias
16.
Planta ; 259(6): 141, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695915

RESUMO

MAIN CONCLUSION: This review highlights the roles of phloem in the long-distance transport and accumulation of As in rice plants, facilitating the formulation of new strategies to reduce the grain As content. Rice is a staple diet for a significant proportion of the global population. As toxicity is a major issue affecting the rice productivity and quality worldwide. Phloem tissues of rice plants play vital roles in As speciation, long-distance transport, and unloading, thereby controlling the As accumulation in rice grains. Phloem transport accounts for a significant proportion of As transport to grains, ranging from 54 to 100% depending on the species [inorganic arsenate (As(V)), arsenite (As(III)), or organic dimethylarsinic acid (DMA(V)]. However, the specific mechanism of As transport through phloem leading to its accumulation in grains remains unknown. Therefore, understanding the molecular mechanism of phloem-mediated As transport is necessary to determine the roles of phloem in long-distance As transport and subsequently reduce the grain As content via biotechnological interventions. This review discusses the roles of phloem tissues in the long-distance transport and accumulation of As in rice grains. This review also highlights the biotechnological approaches using critical genetic factors involved in nodal accumulation, vacuolar sequestration, and cellular efflux of As in phloem- or phloem-associated tissues. Furthermore, the limitations of existing transgenic techniques are outlined to facilitate the formulation of novel strategies for the development of rice with reduced grain As content.


Assuntos
Arsênio , Oryza , Floema , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/genética , Floema/metabolismo , Arsênio/metabolismo , Transporte Biológico , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento
17.
J Plant Physiol ; 297: 154260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38701679

RESUMO

Sulfur is an essential nutrient for all plants, but also crucial for the nitrogen fixing symbiosis between legumes and rhizobia. Sulfur limitation can hamper nodule development and functioning. Until now, it remained unclear whether sulfate uptake into nodules is local or mainly systemic via the roots, and if long-distance transport from shoots to roots and into nodules occurs. Therefore, this work investigates the systemic regulation of sulfur transportation in the model legume Lotus japonicus by applying stable isotope labeling to a split-root system. Metabolite and protein extraction together with mass spectrometry analyses were conducted to determine the plants molecular phenotype and relative isotope protein abundances. Data show that treatments of varying sulfate concentrations including the absence of sulfate on one side of a nodulated root was not affecting nodule development as long as the other side of the root system was provided with sufficient sulfate. Concentrations of shoot metabolites did not indicate a significant stress response caused by a lack of sulfur. Further, we did not observe any quantitative changes in proteins involved in biological nitrogen fixation in response to the different sulfate treatments. Relative isotope abundance of 34S confirmed a long-distance transport of sulfur from one side of the roots to the other side and into the nodules. Altogether, these results provide evidence for a systemic long-distance transport of sulfur via the upper part of the plant to the nodules suggesting a demand driven sulfur distribution for the maintenance of symbiotic N-fixation.


Assuntos
Lotus , Proteínas de Plantas , Nódulos Radiculares de Plantas , Enxofre , Simbiose , Nódulos Radiculares de Plantas/metabolismo , Enxofre/metabolismo , Proteínas de Plantas/metabolismo , Lotus/metabolismo , Transporte Biológico , Fixação de Nitrogênio , Sulfatos/metabolismo , Raízes de Plantas/metabolismo
18.
J Phys Chem B ; 128(20): 4911-4921, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38736363

RESUMO

To combat surging multidrug-resistant Gram-negative bacterial infections, better strategies to improve the efficacy of existing drugs are critical. Because the dual membrane cell envelope is the first line of defense for these bacteria, it is crucial to understand the permeation properties of the drugs through it. Our recent study shows that isosmotic conditions prevent drug permeation inside Gram-negative bacteria, Escherichia coli, while hypoosmotic stress enhances the process. Here, we unravel the reason behind such differential drug penetration. Specifically, we dissect the roles of electrostatic screening and low membrane permeability in the penetration failure of drugs under osmotically balanced conditions. We compare the transport of a quaternary ammonium compound malachite green in the presence of an electrolyte (NaCl) and a wide variety of commonly used organic osmolytes, e.g., sucrose, proline, glycerol, sorbitol, and urea. These osmolytes of different membrane permeability (i.e., nonpermeable sucrose and NaCl, freely permeable urea and glycerol, and partially permeable proline and sorbitol) clarify the role of osmotic stress in cell envelope permeability. The results showcase that under balanced osmotic conditions, drug molecules fail to penetrate inside E. coli cells because of low membrane permeabilities and not because of electrostatic screening imposed by the osmolytes. Contribution of the electrostatic interactions, however, cannot be completely overruled as at osmotically imbalanced conditions, drug transport across the bacterial subcellular compartments is found to be dependent on the osmolytes used.


Assuntos
Permeabilidade da Membrana Celular , Escherichia coli , Pressão Osmótica , Eletricidade Estática , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Transporte Biológico , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Membrana Celular/metabolismo , Membrana Celular/química
20.
Virulence ; 15(1): 2351234, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38773735

RESUMO

Chlamydia infection is an important cause of public health diseases, and no effective vaccine is currently available. Owing to its unique intracellular lifestyle, Chlamydia requires a variety of nutrients and substrates from host cells, particularly sphingomyelin, cholesterol, iron, amino acids, and the mannose-6-phosphate receptor, which are essential for inclusion development. Here, we summarize the recent advances in Chlamydia nutrient acquisition mechanism by hijacking host cell vesicular transport, which plays an important role in chlamydial growth and development. Chlamydia obtains the components necessary to complete its intracellular developmental cycle by recruiting Rab proteins (major vesicular trafficking regulators) and Rab effector proteins to the inclusion, interfering with Rab-mediated multivesicular trafficking, reorienting the nutrition of host cells, and reconstructing the intracellular niche environment. Consequently, exploring the role of vesicular transport in nutrient acquisition offers a novel perspective on new approaches for preventing and treating Chlamydia infection.


Assuntos
Infecções por Chlamydia , Chlamydia , Interações Hospedeiro-Patógeno , Nutrientes , Humanos , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/metabolismo , Chlamydia/metabolismo , Chlamydia/fisiologia , Chlamydia/patogenicidade , Nutrientes/metabolismo , Animais , Transporte Biológico
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