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1.
PLoS One ; 15(10): e0239282, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33095778

RESUMO

OBJECTIVES: To determine if the URO-MCP-1 mouse model for bladder IC/BPS is associated with in vivo bladder hyper-permeability, as measured by contrast-enhanced MRI (CE-MRI), and assess whether molecular-targeted MRI (mt-MRI) can visualize in vivo claudin-2 expression as a result of bladder hyper-permeability. Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic, painful condition of the bladder that affects primarily women. It is known that permeability plays a substantial role in IC/BPS. Claudins are tight junction membrane proteins that are expressed in epithelia and endothelia and form paracellular barriers and pores that determine tight junction permeability. Claudin-2 is a molecular marker that is associated with increased hyperpermeability in the urothelium. MATERIALS AND METHODS: CE-MRI was used to measure bladder hyper-permeability in the URO-MCP-1 mice. A claudin-2-specific mt-MRI probe was used to assess in vivo levels of claudin-2. The mt-MRI probe consists of an antibody against claudin-2 conjugated to albumin that had Gd-DTPA (gadolinium diethylenetriamine pentaacetate) and biotin attached. Verification of the presence of the mt-MRI probe was done by targeting the biotin moiety for the probe with streptavidin-horse radish peroxidase (SA-HRP). Trans-epithelial electrical resistance (TEER) was also used to assess bladder permeability. RESULTS: The URO-MCP-1 mouse model for IC/BPS was found to have a significant increase in bladder permeability, following liposaccharide (LPS) exposure, compared to saline-treated controls. mt-MRI- and histologically-detectable levels of the claudin-2 probe were found to increase with LPS -induced bladder urothelial hyper-permeability in the URO-MCP-1 IC mouse model. Levels of protein expression for claudin-2 were confirmed with immunohistochemistry and immunofluorescence imaging. Claudin-2 was also found to highly co-localize with zonula occlidens-1 (ZO-1), a tight junction protein. CONCLUSION: The combination of CE-MRI and TEER approaches were able to demonstrate hyper-permeability, a known feature associated with some IC/BPS patients, in the LPS-exposed URO-MCP-1 mouse model. This MRI approach could be clinically translated to establish which IC/BPS patients have bladder hyper-permeability and help determine therapeutic options. In addition, the in vivo molecular-targeted imaging approach can provide invaluable information to enhance our understanding associated with bladder urothelium hyper-permeability in IC/BPS patients, and perhaps be used to assist in developing further therapeutic strategies.


Assuntos
Claudina-2/metabolismo , Cistite Intersticial/patologia , Imagem por Ressonância Magnética/métodos , Sondas Moleculares/química , Bexiga Urinária/fisiopatologia , Animais , Anticorpos/química , Anticorpos/imunologia , Claudina-2/imunologia , Cistite Intersticial/metabolismo , Modelos Animais de Doenças , Gadolínio DTPA/química , Imuno-Histoquímica , Lipopolissacarídeos/toxicidade , Camundongos , Permeabilidade/efeitos dos fármacos , Albumina Sérica/química
2.
PLoS One ; 15(9): e0238301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881954

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is a primary astrocytopathy driven by antibodies directed against the aquaporin-4 water channel located at the end-feet of the astrocyte. Although blood-brain barrier (BBB) breakdown is considered one of the key steps for the development and lesion formation, little is known about the molecular mechanisms involved. The aim of the study was to evaluate the effect of human immunoglobulins from NMOSD patients (NMO-IgG) on BBB properties. METHODS: Freshly isolated brain microvessels (IBMs) from rat brains were used as a study model. At first, analysis of the secretome profile from IBMs exposed to purified NMO-IgG, to healthy donor IgG (Control-IgG), or non-treated, was performed. Second, tight junction (TJ) proteins expression in fresh IBMs and primary cultures of brain microvascular endothelial cells (BMEC) was analysed by Western blotting (Wb) after exposition to NMO-IgG and Control-IgG. Finally, functional BBB properties were investigated evaluating the presence of rat-IgG in tissue lysate from brain using Wb in the rat-model, and the passage of NMO-IgG and sucrose in a bicameral model. RESULTS: We found that NMO-IgG induces functional and morphological BBB changes, including: 1) increase of pro-inflammatory cytokines production (CXCL-10 [IP-10], IL-6, IL-1RA, IL-1ß and CXCL-3) in IBMs when exposed to NMO-IgG; 2) decrease of Claudin-5 levels by 25.6% after treatment of fresh IBMs by NMO-IgG compared to Control-IgG (p = 0.002), and similarly, decrease of Claudin-5 by at least 20% when BMEC were cultured with NMO-IgG from five different patients; 3) a higher level of rat-IgG accumulated in periventricular regions of NMO-rats compared to Control-rats and an increase in the permeability of BBB after NMO-IgG treatment in the bicameral model. CONCLUSION: Human NMO-IgG induces both structural and functional alterations of BBB properties, suggesting a direct role of NMO-IgG on modulation of BBB permeability in NMOSD.


Assuntos
Aquaporina 4/imunologia , Barreira Hematoencefálica/metabolismo , Imunoglobulina G/farmacologia , Neuromielite Óptica/patologia , Permeabilidade/efeitos dos fármacos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Células Cultivadas , Quimiocinas/metabolismo , Claudina-5/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Imunoglobulina G/isolamento & purificação , Microvasos/citologia , Microvasos/metabolismo , Neuromielite Óptica/metabolismo , Ratos
3.
Arch Biochem Biophys ; 692: 108522, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32781051

RESUMO

About one quarter of people worldwide are infected with tuberculosis, and multi-drug resistant tuberculosis (MDR-TB) remains a health threat. It is known that two-Component Signal Transduction Systems (TCSs) of Mycobacterium tuberculosis are closely related to tuberculosis resistance, but the mechanism by which orphan response protein Rv3143 regulates strain sensitivity to drug is still unclear. This study found that Rv3143 overexpression resulted in approximately two-fold increase in Mycobacterium smegmatis antibiotic sensitivity. Transcriptome sequencing indicated that 198 potential genes were regulated by Rv3143, affecting the sensitivity of the strain to rifampicin (RIF). MSMEG_4740 promoter binding with Rv3143, was screened out by surface plasmon resonance (SPR). Rv1524, the homologous gene of MSMEG_4740, belonging to the glycosyltransferase (Gtf) family, was related to cell wall modification. By measuring ethidium bromide (EB) accumulation, we found when Rv3143 or MSMEG_4740, or Rv1524 was overexpressed, the cell wall permeability of Mycobacterium smegmatis was increased. In addition, a combination of Rv3143 and RIF was observed. Our findings provide a new strategy for treating drug-resistant tuberculosis by increasing the expression of Rv3143 to enhance the strain sensitivity to antibiotics.


Assuntos
Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Farmacorresistência Bacteriana , Mycobacterium smegmatis/metabolismo , Proteínas de Bactérias/genética , Parede Celular/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Mycobacterium smegmatis/genética , Permeabilidade/efeitos dos fármacos , Rifampina/farmacologia , Transcriptoma/efeitos dos fármacos
4.
PLoS One ; 15(7): e0233252, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701962

RESUMO

Phthiocerol dimycocerosates (PDIMs) are a class of mycobacterial lipids that promote virulence in Mycobacterium tuberculosis and Mycobacterium marinum. It has recently been shown that PDIMs work in concert with the M. tuberculosis Type VII secretion system ESX-1 to permeabilize the phagosomal membranes of infected macrophages. As the zebrafish-M. marinum model of infection has revealed the critical role of PDIM at the host-pathogen interface, we set to determine if PDIMs contributed to phagosomal permeabilization in M. marinum. Using an ΔmmpL7 mutant defective in PDIM transport, we find the PDIM-ESX-1 interaction to be conserved in an M. marinum macrophage infection model. However, we find PDIM and ESX-1 mutants differ in their degree of defect, with the PDIM mutant retaining more membrane damaging activity. Using an in vitro hemolysis assay-a common surrogate for cytolytic activity, we find that PDIM and ESX-1 differ in their contributions: the ESX-1 mutant loses hemolytic activity while PDIM retains it. Our observations confirm the involvement of PDIMs in phagosomal permeabilization in M. marinum infection and suggest that PDIM enhances the membrane disrupting activity of pathogenic mycobacteria and indicates that the role they play in damaging phagosomal and red blood cell membranes may differ.


Assuntos
Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Lipídeos/farmacologia , Macrófagos/citologia , Mycobacterium marinum/metabolismo , Fagossomos/efeitos dos fármacos , Linhagem Celular , Humanos , Macrófagos/efeitos dos fármacos , Mycobacterium marinum/fisiologia , Permeabilidade/efeitos dos fármacos , Fagossomos/metabolismo
5.
PLoS One ; 15(6): e0234039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555710

RESUMO

Sepsis is characterized by organ dysfunction due to a dysregulated immune response to infection. Currently, no effective treatment for sepsis exists. Platelets are recognized as mediators of the immune response and may be a potential therapeutic target for the treatment of sepsis. We previously demonstrated that NLRP3 inflammasome activation in sepsis-induced activated platelets was associated with multi-organ injury in the cecal-ligation puncture (CLP) rat model of sepsis. In this study, we tested the hypothesis that inhibition of NLRP3 would inhibit platelet activation and attenuate multi-organ injury in the CLP rat. CLP (n = 10) or Sham (n = 10) surgery were performed in male and female Sprague-Dawley rats. A subset of CLP rats were treated with MCC950 (50mg/kg/d), a specific NLRP3 inhibitor (CLP+MCC950, n = 10). At 72 hrs. post-CLP, blood and organs were harvested for analysis of platelet activation, NLRP3 activation, inflammation and end organ damage. Platelet activation increased from 8±0.8% in Sham to 16±1% in CLP, and was reduced to 9±1% in CLP+M rats (p<0.05). NLRP3 activation was also increased in platelets of CLP vs Sham. NLRP3 expression was unchanged in kidney and lung after CLP, but Caspase 1 expression and IL-1ß were increased. MCC950 treatment attenuated NLRP3 activation in platelets. Plasma, kidney, and lung levels of NLRP3 inflammasome associated cytokines, IL-1ß and IL-18, were significantly increased in CLP compared to Sham rats. Inhibition of NLRP3 normalized cytokine levels. Glomerular injury, pulmonary edema, and endothelial dysfunction markers were increased in CLP rats vs Sham. MCC950 treatment significantly decreased renal and pulmonary injury and endothelial dysfunction in CLP+M. Our results demonstrate a role for NLRP3 in contributing to platelet activation and multi-organ injury in sepsis.


Assuntos
Ceco/cirurgia , Inflamassomos/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Ativação Plaquetária/efeitos dos fármacos , Punções/efeitos adversos , Sepse/tratamento farmacológico , Sepse/fisiopatologia , Animais , Caspase 1/metabolismo , Citocinas/metabolismo , Endotélio/efeitos dos fármacos , Endotélio/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Ligadura/efeitos adversos , Masculino , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Sepse/metabolismo
6.
Mol Immunol ; 124: 61-69, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32534355

RESUMO

OBJECTIVES: Although mycophenolate mofetil-induced (MMF) effectively improves long-term graft survival, the gastrointestinal (GI) side effects due to MMF-induced GI barrier damage limit its use in clinic. Keratinocyte growth factor (KGF) plays a crucial role in the intestinal protection and repair process. This study is designed to investigate the protective effect of KGF on MMF-induced intestinal mucosal barrier disruption and the potential mechanism. METHODS: Thirty adult male C57BL/6 mice were assigned to one of the following groups: the MMF group, the MMF + KGF group, and the control group (n = 10 in each group). Animals in the MMF group received MMF (500 mg/kg) by gavage once daily for 15 consecutive days; animals in the MMF + KGF group received MMF (500 mg/kg) by gavage and KGF (5 mg/kg) by intraperitoneal injection once daily for 15 consecutive days; and control mice were given an equal volume of vehicle during the 15-day experimental period. In each group, intestinal paracellular permeability, histopathological changes and shifts in tight junction (TJ) protein were evaluated; further, proliferation and apoptosis of intestinal epithelial cells (IECs) were assessed, and intraepithelial lymphocytes (IELs) were isolated and analyzed by flow cytometry. RESULTS: MMF caused intestinal mucosal injury, increased intestinal mucosal permeability, and altered expression of TJ protein. Moreover, MMF treatment inhibited IEC proliferation and increased apoptosis. MMF treatment resulted in a lower proportion of γδ+ T cells in IELs (γδ+ IELs). Conversely, concurrent administration of KGF with MMF effectively alleviated MMF-induced intestinal mucosal disruption, inhibited the increase in intestinal permeability, and maintained TJ protein expression. KGF also reversed the MMF-mediated inhibition of proliferation and promotion of apoptosis in IECs. In addition, KGF significantly enhanced the proportion of γδ+ IELs. CONCLUSION: Our findings suggest that MMF induces intestinal epithelial barrier disruption in mice. KGF may play a protective role to ameliorate the disruption and provide a therapeutic intervention for gastrointestinal disorders induced by MMF.


Assuntos
Fator 7 de Crescimento de Fibroblastos/farmacologia , Imunossupressores/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Ácido Micofenólico/toxicidade , Animais , Apoptose/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
7.
PLoS One ; 15(5): e0227844, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470043

RESUMO

Morroniside is a biologically active polyphenol found in Cornus officinalis Sieb. et Zucc (CO) that exhibits a broad spectrum of pharmacological activities, such as protecting nerves, and preventing diabetic liver damage and renal damage. However, little data are available regarding the mechanism of its intestinal absorption. Here, an in vitro human intestinal epithelial cell model of cultured Caco-2 cells was applied to study the absorption and transport of morroniside. The effects of donor concentration, pH and inhibitors were investigated. The bidirectional permeability of morroniside from the apical (AP) to the basolateral (BL) side and in the reverse direction was studied. When administered at three tested concentrations (5, 25 and 100 µM), the apparent permeability coefficient (Papp) values in the AP-to-BL direction ranged from 1.59 × 10-6 to 2.66 × 10-6 cm/s. In the reverse direction, BL-to-AP, the value was ranged from 2.67 × 10-6 to 4.10 × 10-6 cm/s. The data indicated that morroniside transport was pH-dependent. The permeability of morroniside was affected by treatment with various inhibitors, such as multidrug resistance protein inhibitors MK571 and indomethacin, as well as the breast cancer resistance protein inhibitor apigenin. The mechanisms of the intestinal absorption of morroniside may involve multiple transport pathways, such as the passive diffusion and efflux protein-mediated active transport especially involving multidrug resistance protein 2 and breast cancer resistance protein. After the addition of CO, the Papp values in the AP-to-BL direction increased significantly, therefore, it can be assumed that some ingredients in the CO promote morroniside absorption in the small intestine.


Assuntos
Cornus/química , Glicosídeos/farmacologia , Absorção Intestinal/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indometacina/farmacologia , Absorção Intestinal/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias/patologia , Permeabilidade/efeitos dos fármacos , Propionatos/farmacologia , Quinolinas/farmacologia
8.
Food Chem ; 327: 127057, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464461

RESUMO

Chilling injury (CI) restricts the quality and shelf life of bell pepper fruits; reducing these CI-induced detrimental effects is therefore of high economic and agricultural relevance. Here, we investigated the effects of trisodium phosphate (TSP), salicylic acid (SA), and TSP + SA treatments on pepper fruits under cold stress at 4 °C for 25 d. Combined TSP + SA treatment performed an optimal effect. Specifically, TSP + SA treatment enhanced fatty-acid desaturation efficiency, as indicated by the increased expression of key fatty acid desaturase genes, and higher content of unsaturated fatty acids. Meanwhile, TSP + SA treatment inhibited the CI-induced membrane damage, manifested as lower electrolyte leakage and malondialdehyde content. Furthermore, low field-nuclear magnetic resonance and proline content also revealed that TSP + SA treatment mitigated CI through enhancing water retention in pepper fruits. Collectively, our results may shed new light on optimizing the low-temperature storage conditions of post-harvest peppers.


Assuntos
Capsicum/química , Ácidos Graxos/química , Fosfatos/química , Ácido Salicílico/química , Água/química , Capsicum/efeitos dos fármacos , Capsicum/metabolismo , Parede Celular/efeitos dos fármacos , Temperatura Baixa , Ácidos Graxos/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malondialdeído/química , Malondialdeído/metabolismo , Permeabilidade/efeitos dos fármacos , Fosfatos/farmacologia , Prolina/química , Ácido Salicílico/farmacologia
9.
Braz J Med Biol Res ; 53(5): e9211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321150

RESUMO

Strenuous exercise triggers deleterious effects on the intestinal epithelium, but their mechanisms are still uncertain. Here, we investigated whether a prolonged training and an additional exhaustive training protocol alter intestinal permeability and the putative effect of alanyl-glutamine (AG) pretreatment in this condition. Rats were allocated into 5 different groups: 1) sedentary; 2 and 3) trained (50 min per day, 5 days per week for 12 weeks) with or without 6 weeks oral (1.5 g/kg) AG supplementation; 4 and 5) trained and subjected to an additional exhaustive test protocol with or without oral AG supplementation. Venous blood samples were collected to determine gasometrical indices at the end of the 12-week protocol or after exhaustive test. Lactate and glucose levels were determined before, during, and after the exhaustive test. Ileum tissue collected after all experimental procedures was used for gene expression analysis of Zonula occludens 1 (ZO-1), occludin, claudin-2, and oligopeptide transporter 1 (PepT-1). Intestinal permeability was assessed by urinary lactulose/mannitol test collected after the 12-week protocol or the exhaustive test. The exhaustive test decreased pH and base excess and increased pCO2. Training sessions delayed exhaustion time and reduced the changes in blood glucose and lactate levels. Trained rats exhibited upregulation of PEPT-1, ZO-1, and occludin mRNA, which were partially protected by AG. Exhaustive exercise induced intestinal paracellular leakage associated with the upregulation of claudin-2, a phenomenon protected by AG treatment. Thus, AG partially prevented intestinal training adaptations but also blocked paracellular leakage during exhaustive exercise involving claudin-2 and occludin gene expression.


Assuntos
Dipeptídeos/administração & dosagem , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/fisiopatologia , Permeabilidade/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Animais , Masculino , Modelos Animais , Ratos , Ratos Wistar
10.
J Mycol Med ; 30(2): 100949, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32234349

RESUMO

Onychomycosis is one of the most prevalent and severe nail fungal infections, which is affecting a wide population across the globe. It leads to variations like nail thickening, disintegration and hardening. Oral and topical drug delivery systems are the most desirable in treating onychomycosis, but the efficacy of the results is low, resulting in a relapse rate of 25-30%. Due to systemic toxicity and various other disadvantages associated with oral therapy like gastrointestinal, hepatotoxicity, topical therapy is commonly used. Topical therapy improves patient compliance and reduces the cost of treatment. However, due to poor penetration of topical therapy across the nail plate, research is focused on different chemical, mechanical and physical methods to improve drug delivery. Penetration enhancers like Thioglycolic acid, Hydroxypropyl-ß-cyclodextrin (HP-ß-CD), Sodium lauryl sulfate (SLS), carbocysteine, N-acetylcysteine etc. have shown results enhancing the drug penetration across the nail plate. Results with physical techniques such as iontophoresis, laser and Photodynamic therapy are quite promising, but the long-term suitability of these devices is in need to be determined. In this article, a brief analysis of the treatment procedures, factors affecting drug permeation across nail plate, chemical, mechanical and physical devices used to increase the drug delivery through nails for the onychomycosis management has been achieved.


Assuntos
Onicomicose/terapia , Administração Oral , Administração Tópica , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Química Farmacêutica/métodos , Terapia Combinada , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Iontoforese/métodos , Iontoforese/tendências , Terapia a Laser/métodos , Terapia a Laser/tendências , Unhas/efeitos dos fármacos , Unhas/metabolismo , Unhas/efeitos da radiação , Onicomicose/tratamento farmacológico , Onicomicose/epidemiologia , Onicomicose/microbiologia , Permeabilidade/efeitos dos fármacos , Permeabilidade/efeitos da radiação , Fotoquimioterapia/métodos , Fotoquimioterapia/tendências
11.
J Nanobiotechnology ; 18(1): 67, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345323

RESUMO

BACKGROUND: Exenatide is an insulinotropic peptide drug for type 2 diabetes treatment with low risk of hypoglycemia, and is administrated by subcutaneous injection. Oral administration is the most preferred route for lifelong treatment of diabetes, but oral delivery of peptide drug remains a significant challenge due to the absorption obstacles in gastrointestinal tract. We aimed to produce exenatide-loaded nanoparticles containing absorption enhancer, protectant and stabilizer using FDA approved inactive ingredients and easy to scale-up method, and to evaluate their long-term oral therapeutic effect in type 2 diabetes db/db mice. RESULTS: Two types of nanoparticles, named COM NPs and DIS NPs, were fabricated using anti-solvent precipitation method. In COM NPs, the exenatide was complexed with cholic acid and phosphatidylcholine to increase the exenatide loading efficiency. In both nanoparticles, zein acted as the cement and the other ingredients were embedded in zein nanoparticles by hydrophobic interaction. Casein acted as the stabilizer. The nanoparticles had excellent lyophilization, storage and re-dispersion stability. Hypromellose phthalate protected the loaded exenatide from degradation in simulated gastric fluid. Cholic acid promoted the intestinal absorption of the loaded exenatide via bile acid transporters. The exenatide loading efficiencies of COM NPs and DIS NPs were 79.7% and 53.6%, respectively. The exenatide oral pharmacological availability of COM NPs was 18.6% and DIS NPs was 13.1%. COM NPs controlled the blood glucose level of the db/db mice well and the HbA1c concentration significantly decreased to 6.8% during and after 7 weeks of once daily oral administration consecutively. Both DIS NPs and COM NPs oral groups substantially increased the insulin secretion by more than 60% and promoted the ß-cell proliferation by more than 120% after the 7-week administration. CONCLUSIONS: Both COM NPs and DIS NPs are promising systems for oral delivery of exenatide, and COM NPs are better in blood glucose level control than DIS NPs. Using prolamin to produce multifunctional nanoparticles for oral delivery of peptide drug by hydrophobic interaction is a simple and effective strategy.


Assuntos
Exenatida/farmacologia , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Nanopartículas/química , Zeína/química , Administração Oral , Animais , Glicemia/análise , Ácido Cólico/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Exenatida/administração & dosagem , Exenatida/química , Trato Gastrointestinal/química , Trato Gastrointestinal/patologia , Hemoglobina A Glicada/análise , Meia-Vida , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Células Secretoras de Insulina/classificação , Células Secretoras de Insulina/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/metabolismo , Permeabilidade/efeitos dos fármacos , Fosfatidilcolinas/química
12.
Ann N Y Acad Sci ; 1470(1): 14-24, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32112442

RESUMO

The blood-brain barrier (BBB) contributes to the maintenance of brain homeostasis. Gut microbiome composition affects BBB development and expression of tight junction proteins in rodents. However, we still do not know if there is any direct effect of gut microbial composition on BBB permeability and function in normal adult animals. In the current study, we determined temporal and spatial changes in BBB permeability of rhesus monkeys receiving amoxicillin-clavulanic acid (AC) by monitoring the cerebrospinal fluid/serum albumin ratio and the volume transfer constant (Ktrans ). We showed that oral, but not intravenous, AC was associated with subsequent significant alteration in gut microbial composition and an increase in BBB permeability in all monkeys, especially in the thalamus area. Acetic and propionic acids might play a pivotal role in this newly found communication between the gut and the central nervous system. Antibiotic-induced gut microbial composition change, especially the decrease in acetic acid- and propionic acid-producing phyla and genera, might have a potential effect on the increase in BBB permeability, which may contribute to a variety of neurological and psychological diseases.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Macaca mulatta , Permeabilidade/efeitos dos fármacos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
13.
J Mycol Med ; 30(2): 100938, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32111505

RESUMO

Onychomycosis are fungal nail infections comprising of about 50% of onychopathies and are commonly caused by dermatophytes. The treatment of this dermatomycosis requires a long period of time and is associated with high rates of recurrence. In view of the need to evaluate the antifungal performance of promising preclinical compounds, we developed, in this study, a practical and accessibleex vivo model for establishing a Trichophyton rubrum onychomycosis framework using porcine hooves. This model has as its main advantage the similar structural and three-dimensional characteristics that the porcine hooves have with the human nail. The proposed model allowed to evaluate the antifungal activity of a new antifungal compound and a reference drug (terbinafine), both already incorporated into a nail lacquer for topical use. Treatments with compound 3-selenocyanate-indole (Se4a) and with terbinafine incorporated into this nail lacquer completely inhibited fungal growth, corresponding to the profile of in vitro activity observed against T. rubrum. This study concludes that the ex vivo porcine hoof model is an effective alternative method for preclinical screening of drugs or new topical compounds developed to combat onychomycosis. Further studies are needed to compare the permeability of porcine hooves with human nails permeability.


Assuntos
Antifúngicos/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Casco e Garras/patologia , Onicomicose/tratamento farmacológico , Técnicas de Cultura de Órgãos , Suínos , Administração Tópica , Animais , Antifúngicos/farmacologia , Cianatos/química , Casco e Garras/efeitos dos fármacos , Humanos , Laca , Testes de Sensibilidade Microbiana/métodos , Modelos Biológicos , Onicomicose/patologia , Permeabilidade/efeitos dos fármacos , Compostos de Selênio/química , Terbinafina/administração & dosagem , Terbinafina/farmacologia , Trichophyton/efeitos dos fármacos , Trichophyton/crescimento & desenvolvimento
14.
J Vis Exp ; (156)2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32116297

RESUMO

The human blood-brain barrier (BBB) is characterized by a very low permeability for biomolecules in order to protect and regulate the metabolism of the brain. The BBB is mainly formed out of endothelial cells embedded in collagen IV and fibronectin-rich basement membranes. Several pathologies result from dysfunction of the BBB followed by microbial traversal, causing diseases such as meningitis. In order to test the effect of multiple parameters, including different drugs and anesthetics, on the permeability of the BBB we established a novel human cell culture model mimicking the BBB with human brain microvascular endothelial cells. The endothelial cells are grown on collagen IV and fibronectin-coated filter units until confluence and can then be treated with different compounds of interest. In order to demonstrate a microbial traversal, the upper chamber with the apical surface of the endothelial cells is inoculated with bacteria. After an incubation period, samples of the lower chamber are plated on agar plates and the obtained colonies are counted, whereby the number of colonies correlate with the permeability of the BBB. Endogenous cellular factors can be analyzed in this experimental set-up in order to elucidate basic cellular mechanisms of the endothelial cells contributing to the BBB. In addition, this platform allows performing a screen for compounds that might affect the permeability of the endothelial cells. Finally, bacterial traversal can be studied and linked to different pathologies, such as meningitis. It might be possible to extend the model and analyze the pathways of the bacteria through the BBB. In this article, we provide a detailed protocol of the described method to investigate the permeability of the BBB.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/microbiologia , Células Endoteliais/microbiologia , Microvasos/citologia , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/metabolismo , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Fibronectinas/farmacologia , Glicosilação , Humanos , Permeabilidade/efeitos dos fármacos
15.
Fluids Barriers CNS ; 17(1): 5, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036791

RESUMO

BACKGROUND: Excitotoxicity is a central pathological pathway in many neurological diseases with blood-brain barrier (BBB) dysfunction. Kainate, an exogenous excitotoxin, induces epilepsy and BBB damage in animal models, but the direct effect of kainate on brain endothelial cells has not been studied in detail. Our aim was to examine the direct effects of kainate on cultured cells of the BBB and to test three anti-inflammatory and antioxidant drugs used in clinical practice, simvastatin, edaravone and dexamethasone, to protect against kainate-induced changes. METHODS: Primary rat brain endothelial cell, pericyte and astroglia cultures were used to study cell viability by impedance measurement. BBB permeability was measured on a model made from the co-culture of the three cell types. The production of nitrogen monoxide and reactive oxygen species was followed by fluorescent probes. The mRNA expression of kainate receptors and nitric oxide synthases were studied by PCR. RESULTS: Kainate damaged brain endothelial cells and made the immunostaining of junctional proteins claudin-5 and zonula occludens-1 discontinuous at the cell border indicating the opening of the barrier. The permeability of the BBB model for marker molecules fluorescein and albumin and the production of nitric oxide in brain endothelial cells were increased by kainate. Simvastatin, edaravone and dexamethasone protected against the reduced cell viability, increased permeability and the morphological changes in cellular junctions caused by kainate. Dexamethasone attenuated the elevated nitric oxide production and decreased the inducible nitric oxide synthase (NOS2/iNOS) mRNA expression increased by kainate treatment. CONCLUSION: Kainate directly damaged cultured brain endothelial cells. Simvastatin, edaravone and dexamethasone protected the BBB model against kainate-induced changes. Our results confirmed the potential clinical usefulness of these drugs to attenuate BBB damage.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Edaravone/farmacologia , Células Endoteliais/efeitos dos fármacos , Sinvastatina/farmacologia , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Células Endoteliais/metabolismo , Óxido Nítrico/metabolismo , Permeabilidade/efeitos dos fármacos , Ratos
16.
Sci Rep ; 10(1): 2027, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029808

RESUMO

A multifunctional system comprised of hyaluronic acid microneedles was developed as an effective transdermal delivery platform for rapid local delivery. The microneedles can regulate the filling amount on the tip, by controlling the concentration of hyaluronic acid solution. Ultrasonication induces dissolution of the HA microneedles via vibration of acoustic pressure, and AC iontophoresis improves the electrostatic force-driven diffusion of HA ions and rhodamine B. The effect of ultrasound on rhodamine release was analyzed in vitro using a gelatin hydrogel. The frequency and voltage dependence of the AC on the ion induction transfer was also evaluated experimentally. The results showed that the permeability of the material acts as a key material property. The delivery system based on ultrasonication and iontophoresis in microneedles increases permeation, thus resulting in shorter initial delivery time than that required by delivery systems based on passive or ultrasonication alone. This study highlights the significance of the combination between ultrasonic waves and iontophoresis for improving the efficiency of the microneedles, by shortening the reaction duration. We anticipate that this system can be extended to macromolecular and dependence delivery, based on drug response time.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ácido Hialurônico/farmacologia , Iontoforese/métodos , Adesivo Transdérmico , Administração Cutânea , Animais , Sistemas de Liberação de Medicamentos/instrumentação , Liberação Controlada de Fármacos/efeitos dos fármacos , Liberação Controlada de Fármacos/efeitos da radiação , Iontoforese/instrumentação , Agulhas , Permeabilidade/efeitos dos fármacos , Permeabilidade/efeitos da radiação , Rodaminas/administração & dosagem , Rodaminas/farmacocinética , Pele/metabolismo , Pele/efeitos da radiação , Absorção Cutânea/efeitos da radiação , Suínos , Ondas Ultrassônicas
17.
Sci Rep ; 10(1): 1577, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005861

RESUMO

The iron chelator Deferasirox (DFX) causes severe toxicity in patients for reasons that were previously unexplained. Here, using the kidney as a clinically relevant in vivo model for toxicity together with a broad range of experimental techniques, including live cell imaging and in vitro biophysical models, we show that DFX causes partial uncoupling and dramatic swelling of mitochondria, but without depolarization or opening of the mitochondrial permeability transition pore. This effect is explained by an increase in inner mitochondrial membrane (IMM) permeability to protons, but not small molecules. The movement of water into mitochondria is prevented by altering intracellular osmotic gradients. Other clinically used iron chelators do not produce mitochondrial swelling. Thus, DFX causes organ toxicity due to an off-target effect on the IMM, which has major adverse consequences for mitochondrial volume regulation.


Assuntos
Deferasirox/farmacologia , Quelantes de Ferro/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Animais , Linhagem Celular , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Membranas Mitocondriais/metabolismo , Permeabilidade/efeitos dos fármacos
18.
Sci Rep ; 10(1): 2793, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066787

RESUMO

Carbon-based nanomaterials are being increasingly used, demanding strong information to support their safety in terms of human health. As ingestion is one of the most important exposure routes in humans, we have determined their potential risk by using an in vitro model simulating the human intestinal barrier and evaluated the effects of both graphene oxide (GO) and graphene nanoplatelets (GNPs). A coculture of differentiated Caco-2/HT29 cells presenting inherent intestinal epithelium characteristics (i.e. mucus secretion, brush border, tight junctions, etc.) were treated with GO or GNPs for 24 h. Different endpoints such as viability, membrane integrity, NPs localization, cytokines secretion, and genotoxic damage were evaluated to have a wide view of their potentially harmful effects. No cytotoxic effects were observed in the cells that constitute the barrier model. In the same way, no adverse effects were detected neither in the integrity of the barrier (TEER) nor in its permeability (LY). Nevertheless, a different bio-adhesion and biodistribution behavior was observed for GO and GNPs by confocal microscopy analysis, with a more relevant uptake of GNPs. No oxidative damage induction was detected, either by the DCFH-DA assay or the FPG enzyme in the comet assay. Conversely, both GO and GNPs were able to induce DNA breaks, as observed in the comet assay. Finally, low levels of anti-inflammatory cytokines were detected, suggesting a weak anti-inflammatory response. Our results show the moderate/severe risk posed by GO/GNPs exposures, given the observed genotoxic effects, suggesting that more extensive genotoxic evaluations must be done to properly assess the genotoxic hazard of these nanomaterials.


Assuntos
Dano ao DNA/efeitos dos fármacos , Grafite/farmacologia , Intestinos/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Células CACO-2/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Grafite/química , Células HT29 , Humanos , Mucosa Intestinal/efeitos dos fármacos , Nanopartículas/química , Nanoestruturas/química , Junções Íntimas/efeitos dos fármacos
19.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32102880

RESUMO

Rabies, caused by rabies virus (RABV), is a fatal encephalitis in humans and other mammals, which continues to present a public health threat in most parts of the world. Our previous study demonstrated that Toll-like receptor 7 (TLR7) is essential in the induction of anti-RABV antibodies via the facilitation of germinal center formation. In the present study, we investigated the role of TLR7 in the pathogenicity of RABV in a mouse model. Using isolated plasmacytoid dendritic cells (pDCs), we demonstrated that TLR7 is an innate recognition receptor for RABV. When RABV invaded from the periphery, TLR7 detected viral single-stranded RNA and triggered immune responses that limited the virus's entry into the central nervous system (CNS). When RABV had invaded the CNS, its detection by TLR7 led to the production of cytokines and chemokines and an increase the permeability of the blood-brain barrier. Consequently, peripheral immune cells, including pDCs, macrophages, neutrophils, and B cells infiltrated the CNS. While this immune response, triggered by TLR7, helped to clear viruses, it also increased neuroinflammation and caused immunopathology in the mouse brain. Our results demonstrate that TLR7 is an innate recognition receptor for RABV, which restricts RABV invasion into the CNS in the early stage of viral infection but also contributes to immunopathology by inducing neuroinflammation.IMPORTANCE Developing targeted treatment for RABV requires understanding the innate immune response to the virus because early virus clearance is essential for preventing the fatality when the infection has progressed to the CNS. Previous studies have revealed that TLR7 is involved in the immune response to RABV. Here, we establish that TLR7 recognizes RABV and facilitates the production of some interferon-stimulated genes. We also demonstrated that when RABV invades into the CNS, TLR7 enhances the production of inflammatory cytokines which contribute to immunopathology in the mouse brain. Taken together, our findings suggest that treatments for RABV must consider the balance between the beneficial and harmful effects of TLR7-triggered immune responses.


Assuntos
Vírus da Raiva/metabolismo , Raiva/patologia , Receptor 7 Toll-Like/metabolismo , Animais , Anticorpos Antivirais , Linfócitos B/imunologia , Barreira Hematoencefálica/metabolismo , Encéfalo/virologia , Quimiocinas/metabolismo , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Imunidade Inata/imunologia , Interferons , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade/efeitos dos fármacos , Raiva/imunologia , Vírus da Raiva/imunologia , Vírus da Raiva/patogenicidade , Receptor 7 Toll-Like/imunologia
20.
Drug Dev Ind Pharm ; 46(2): 227-235, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928244

RESUMO

Objective: Aim of the present work was to optimize and formulate resveratrol loaded vesicular cream intended for dermal delivery of resveratrol with high skin deposition potential.Methods: Formulation was developed and optimized using Central Composite Design. Amount of phospholipid and sodium cholate were selected as critical material attributes and vesicle size and entrapment efficiency of resveratrol were taken as critical quality attributes. To increase the skin applicability and patient compliance, vesicles were further developed as vesicular cream which was then thoroughly characterized for physicochemical parameters, ex vivo skin permeation/deposition profile and antioxidant potential.Results: Vesicle size and entrapment efficiency of the optimized batch were found to be 178.9 ± 12.87 nm with 72.32 ± 3.45% respectively. Physicochemical properties and viscosity of cream formulation were also found to be favorable for skin applicability. Permeation flux at the end of 24 h was found to be 2.70 ± 0.73, 4.45 ± 0.56 and 4.95 ± 0.69 µg cm-2 h-1 for conventional cream, vesicular dispersion, and vesicular cream formulation respectively. Higher drug deposition in the skin via vesicular cream formulation was observed i.e. 335.2 ± 4.12 µg cm-2 (70.16 ± 0.87%) as compared to conventional cream i.e. 67.12 ± 19.63 µg cm-2 (14.05 ± 4.11%). Resveratrol encapsulated in vesicular cream has retained its inherent antioxidant activity suggesting the stability of resveratrol in vesicular cream.Conclusion: Thus, it can be concluded that deformable vesicular cream is capable of delivering encapsulated bioactive in deeper layers of skin, where it can be retained for achieving higher dermatological benefits.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/química , Pomadas/administração & dosagem , Pomadas/química , Resveratrol/administração & dosagem , Resveratrol/química , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Química Farmacêutica/métodos , Portadores de Fármacos/química , Tamanho da Partícula , Permeabilidade/efeitos dos fármacos , Fosfolipídeos/química , Absorção Cutânea/efeitos dos fármacos , Suínos , Viscosidade/efeitos dos fármacos
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