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1.
Drug Deliv Transl Res ; 9(3): 694-706, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30825078

RESUMO

Diabetes mellitus is a chronic metabolic disorder characterized by insulin deficiency and impaired glucose metabolism. Overexpression of cAMP response element binding protein (CREB)-regulated transcriptional coactivator 2 (CRTC2) plays an important role in high gluconeogenesis in patients with diabetes type II. Using RNA interference technology for silencing CRTC2 gene expression could be helpful in controlling the level of blood glucose and gluconeogenesis. In this study, we designed a siRNA delivery platform comprising blended chitosan lactate (CT) and polyethylene glycol (PEG) conjugated with glycyrrhetinic acid (GA) for controlling gluconeogenesis. The nanoparticles showed spherical and smooth surface with ~ 189-nm size and + 5.1 zeta potential. Targeted nanoparticles were efficiently stable in serum and different levels of heparin media over 48 h. The gene knockdown efficiency of nanoparticles was comparable to Lipofectamine®, while they had no significant in vitro and in vivo toxicity. The in vivo therapeutic efficacy of targeted nanoparticles was also confirmed by reduced amount of fasting blood sugar in diabetic rat models. Furthermore, the nanoparticles were mostly accumulated in the liver after 2 h indicating the significant targeting ability of the prepared nanoparticles. Therefore, CT/PEG-GA nanoparticles can be considered as a potential candidate for targeted delivery of siRNA into hepatocytes in order to regulate gluconeogenesis in diabetes.


Assuntos
Quitosana/administração & dosagem , Gluconeogênese/efeitos dos fármacos , Ácido Glicirretínico/administração & dosagem , Ácido Láctico/administração & dosagem , Fígado/efeitos dos fármacos , Nanopartículas/administração & dosagem , Polietilenoglicóis/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Fatores de Transcrição/genética , Animais , Quitosana/farmacocinética , Quitosana/toxicidade , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/terapia , Expressão Gênica , Ácido Glicirretínico/farmacocinética , Ácido Glicirretínico/toxicidade , Células Hep G2 , Humanos , Ácido Láctico/farmacocinética , Ácido Láctico/toxicidade , Fígado/metabolismo , Fígado/patologia , Masculino , Nanopartículas/toxicidade , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/toxicidade , RNA Interferente Pequeno/farmacocinética , RNA Interferente Pequeno/toxicidade , Ratos Wistar , Distribuição Tecidual
2.
Toxicol In Vitro ; 57: 164-173, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30851411

RESUMO

The incidence of sensitive skin with stinging and itch following chemical exposure in products such as cosmetics is increasing, but molecular mechanisms underlying this pathophysiology remain understudied. Here we performed transcriptional analysis of reconstructed human epidermis (RHE) 1, 6, and 24 h following topical lactic acid (LA) application, a known inducer of the sensitive skin reaction. Since little is known about the specific role of keratinocyte transcriptional changes in mediating stinging and itch, we performed pathway analysis using several publically available databases and then focused on significantly changed transcripts involved in stress responses and itch signaling using the Comparative Toxicogenomics Database. LA treatment induced damage-associated genes HSPA1A, DDIT3, IL1A, and HMGB2. Neurotrophic factors including BDNF, ARTN, PGE2, and chemokines were also upregulated. Stimulation of the RHE with 5% LA did not reduce cell viability, but reduced the trans-epidermal electric resistance, suggesting barrier dysfunction. Accordingly, skin barrier formation genes such as filaggrins (FLG, FLG2) and corneodesmosin (CDSN) were downregulated. To our knowledge, this is the first study focusing on transcriptional changes underlying the stinging response of keratinocytes upon LA stimulation. While follow-up research is needed, this study provides new insight into the mechanisms underlying the sensitive skin reaction.


Assuntos
Epiderme/efeitos dos fármacos , Irritantes/toxicidade , Ácido Láctico/toxicidade , Prurido/genética , Transcriptoma/efeitos dos fármacos , Epiderme/metabolismo , Humanos
3.
Glia ; 67(1): 27-36, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30430652

RESUMO

Astrocytes play a key role in the maintenance of synaptic transmission by producing L-lactate via the astrocyte-neuron lactate shuttle (ANLS). Astrocyte activation in the spinal cord is involved in the expression of neuropathic pain. We investigated the role of the ANLS in the spinal cord on hyperalgesia in neuropathic pain in mice. Specific activation of dorsal horn astrocytes induced mechanical hyperalgesia, which was attenuated by α-cyano-4-hydroxycinnamate (4-CIN), an inhibitor of monocarboxylate transporters that deliver L-lactate from astrocytes to neurons. Intrathecal L-lactate administration lowered the mechanical nociceptive threshold, which was attenuated by pretreatment with 4-CIN and isosafrole (a lactate dehydrogenase inhibitor), but not gliotoxin. Intrathecal L-lactate administration significantly upregulated c-Fos and cofilin phosphorylation, which was reversed by 4-CIN. The lowered mechanical nociceptive threshold was significantly attenuated by intrathecal fluorocitrate (an astrocyte-specific Krebs cycle inhibitor), 4-CIN, and isosafrole treatment. Thus, these results suggested that, in neuropathic pain, mechanical hyperalgesia was maintained by excessive L-lactate supplied by activated astrocytes via an aberrant ANLS.


Assuntos
Astrócitos/metabolismo , Hiperalgesia/metabolismo , Ácido Láctico/metabolismo , Neurônios/metabolismo , Nociceptividade/fisiologia , Medula Espinal/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Hiperalgesia/induzido quimicamente , Injeções Espinhais , Ácido Láctico/administração & dosagem , Ácido Láctico/toxicidade , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos
4.
J Agric Food Chem ; 66(30): 7889-7898, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30039704

RESUMO

The use of herbicides plays a vital role in controlling weeds and conserving crops; however, its usage generates both environmental and economic problems. For example, herbicides pose a financial issue as farmers must apply large quantities to protect crops due to absorption rates of less than 0.1%. Therefore, there is a great need for the development of new methods to mitigate these issues. Here, we report for the first time the synthesis of poly(lactic- co-glycolic-acid) (PLGA) nanoherbicides loaded with atrazine as an active ingredient. We used potato plants as a biological model to assess the herbicidal activity of the engineered PLGA nanoherbicides. Our method produced nanoherbicides with an average size of 110 ± 10 nm prior to lyophilization. Fifty percent of the loaded atrazine in the PLGA matrix is released in 72 h. Furthermore, we performed Monte Carlo simulations to determine the chemical interaction among atrazine, PLGA, and the solvent system. One of the most significant outcomes of these simulations was to find the formation of a hydrogen bond of 1.9 Å between PLGA and atrazine, which makes this interaction very stable. Our in vitro findings showed that as atrazine concentration is increased in PLGA nanoparticles, potato plants undergo a significant decrease in stem length, root length, fresh weight, dry weight, and the number of leaves, with root length being the most affected. These experimental results suggest the herbicidal effectiveness of atrazine-loaded PLGA nanoherbicides in inhibiting the growth of the potato plant. Hence, we present the proof-of-concept for using PLGA nanoherbicides as an alternative method for inhibiting weed growth. Future studies will involve a deep understanding of the mechanism of plant-nanoherbicide interaction as well as the role of PLGA as a growth potentiator.


Assuntos
Atrazina/química , Portadores de Fármacos/química , Herbicidas/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Portadores de Fármacos/toxicidade , Composição de Medicamentos , Herbicidas/toxicidade , Ácido Láctico/toxicidade , Nanopartículas/toxicidade , Tamanho da Partícula , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/crescimento & desenvolvimento
5.
Int J Pharm ; 545(1-2): 318-328, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29746999

RESUMO

Plasmid DNA (pDNA) vaccines have the potential for protection against a wide range of diseases including rabies but are rapid in degradation and poor in uptake by antigen-presenting cells. To overcome the limitations, we fabricated a pDNA nanoparticulate vaccine. The negatively charged pDNA was adsorbed onto the surface of cationic PLGA (poly (d, l-lactide-co-glycolide))-chitosan nanoparticles and were used as a delivery vehicle. To create a hydrogel for sustainable vaccine release, we dispersed the pDNA nanoparticles in poloxamer 407 gel which is liquid at 4 °C and turns into soft gels at 37 °C, providing ease of administration and preventing burst release of pDNA. Complete immobilization of pDNA to cationic nanoparticles was achieved at a pDNA to nanoparticles ratio (P/N) of 1/50. Cellular uptake of nanoparticles was both time and concentration dependent and followed a saturation kinetics with Vmax of 11.389 µg/mL h and Km of 139.48 µg/mL. The in vitro release studies showed the nanoparticulate vaccine has a sustained release for up to 24 days. In summary, pDNA PLGA-chitosan nanoparticles were non-cytotoxic, their buffering capacity and cell uptake were enhanced, and sustained the release of pDNA. We expect our pDNA vaccine's potency will be greatly improved in the animal studies.


Assuntos
Quitosana/química , Portadores de Fármacos , Ácido Láctico/química , Nanopartículas , Poloxâmero/química , Ácido Poliglicólico/química , Vacinas Antirrábicas/química , Animais , Linhagem Celular , Quitosana/toxicidade , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ensaio de Desvio de Mobilidade Eletroforética , Hidrogéis , Cinética , Ácido Láctico/toxicidade , Camundongos Endogâmicos C57BL , Nanotecnologia , Poloxâmero/toxicidade , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vacinas Antirrábicas/administração & dosagem , Vacinas Antirrábicas/imunologia , Vacinas Antirrábicas/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tecnologia Farmacêutica/métodos , Vacinas de DNA/química , Vacinas de DNA/imunologia
6.
Arch Dermatol Res ; 310(6): 495-504, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29728858

RESUMO

We determined whether compensating ceramides in the stratum corneum (SC) may ameliorate the impaired barrier function and subsequently attenuate the enhanced skin sensitivity. Treatment for 4 weeks with the ceramide complex cream or the placebo cream significantly ameliorated the intensity of lactic acid sensations in 39 female subjects with sensitive skin, the degree of which was attenuated to a greater extent at 1 week by the ceramide complex cream compared with the placebo cream. The amelioration of skin sensations was accompanied by a significant increase in total ceramide content in the SC elicited by the ceramide complex cream that was significantly more effective than the placebo cream at 4 weeks. Consistently, TEWL and conductance values were significantly decreased or increased at 1 and 4 weeks, respectively, to a greater extent by the ceramide complex cream than by the placebo cream. TEWL levels were significantly correlated with the increased levels of SC total ceramide in the ceramide complex cream-treated skin but not in the placebo cream-treated skin. Thus, the amelioration of lactic acid sensations by topical application of a ceramide complex cream, provides a deep insight into the pathophysiology of sensitive skin as a reduced barrier function-dependent sub-clinical sensory response.


Assuntos
Ceramidas/farmacologia , Epiderme/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Administração Cutânea , Ceramidas/biossíntese , Método Duplo-Cego , Quimioterapia Combinada/métodos , Epiderme/inervação , Epiderme/metabolismo , Eucalyptus/química , Feminino , Voluntários Saudáveis , Humanos , Ácido Láctico/toxicidade , Placebos , Sensação/efeitos dos fármacos , Creme para a Pele , Perda Insensível de Água/efeitos dos fármacos
7.
Toxicol In Vitro ; 50: 433-438, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29462660

RESUMO

Several irritants were used in the in vitro irritation medical device round robin. The objective of this study was to verify their irritation potential using the human patch test (HPT), an in vitro assay, and in vivo data. The irritants were lactic acid (LA), heptanoic acid (HA), sodium dodecyl sulfate (SDS), Genapol® X-80 (GP), and Y-4 polymer. Dilute saline and sesame seed oil (SSO) solutions of each were evaluated using a 4 and 18 h HPT and the EpiDerm™ SIT-MD RhE assay; results were then compared to existing rabbit skin irritation test data. Results from the 4 h HPT were negative in most cases except for GP and SDS, while the 18 h HPT also identified some LA, HA, and GP samples as irritants. EpiDerm™ SIT-MD correctly identified all irritants except GP in SSO due to limited solubility. Data from cutaneous rabbit irritation tests were negative, while all intracutaneous results were strongly or weakly positive except for the most dilute GP solutions. These findings indicate that EpiDerm™ SIT-MD results correlate with those from the rabbit intracutaneous test and confirm that RhE assays are suitable replacements for animals in evaluating the tissue irritation potential of medical devices.


Assuntos
Equipamentos e Provisões , Irritantes/toxicidade , Testes do Emplastro/métodos , Testes de Irritação da Pele/métodos , Alternativas aos Testes com Animais , Animais , Benchmarking , Ácidos Heptanoicos/toxicidade , Humanos , Ácido Láctico/toxicidade , Polietilenoglicóis/toxicidade , Cloreto de Polivinila/toxicidade , Coelhos , Reprodutibilidade dos Testes , Pele/efeitos dos fármacos , Dodecilsulfato de Sódio/toxicidade
8.
J Cell Physiol ; 233(2): 1168-1178, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28464242

RESUMO

Magnetic nanoparticles (MNPs) are used as contrast agents and targeted drug delivery systems (TDDS) due to their favorable size, surface charge, and magnetic properties. Unfortunately, the toxicity associated with MNPs limits their biological applications. Surface functionalization of MNPs with selective polymers alters the surface chemistry to impart better biocompatibility. We report the preparation of surface functionalized MNPs using iron oxide NPs (MNPs), poly (lactic-co-glycolic acid) (PLGA), and sodium alginate via co-precipitation, emulsification, and electro-spraying, respectively. The NPs are in the nanosize range and negatively charged. Morphological and structural analyses affirm the surface functionalized nanostructure of the NPs. The surface functionalized MNPs are biocompatible, and demonstrate enhanced intracellular delivery under an applied magnetic field (H), which evinces the targeting ability of MNPs. After NP treatment, the physico-mechanical properties of fibroblasts are decided by the selective MNP uptake under "on" or "off" magnetic field conditions. We envision potential use of biocompatible surface functionalized MNP for intracellular-, targeted-DDS, imaging, and for investigating cellular mechanics.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Reagentes para Ligações Cruzadas/química , Ácido Láctico/química , Campos Magnéticos , Magnetismo/métodos , Nanopartículas de Magnetita/química , Nanomedicina/métodos , Ácido Poliglicólico/química , Alginatos/metabolismo , Alginatos/toxicidade , Animais , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/toxicidade , Transporte Biológico , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/metabolismo , Reagentes para Ligações Cruzadas/toxicidade , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácido Glucurônico/toxicidade , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Ácidos Hexurônicos/toxicidade , Ácido Láctico/metabolismo , Ácido Láctico/toxicidade , Nanopartículas de Magnetita/toxicidade , Camundongos , Células NIH 3T3 , Tamanho da Partícula , Ácido Poliglicólico/metabolismo , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Propriedades de Superfície
9.
Pharm Dev Technol ; 23(4): 324-333, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27670289

RESUMO

Frequent intravitreal injections are currently used to overcome the ocular barriers and provide sufficient drug to the posterior eye segment. However, intravitreal injections have been associated with a number of complications and high treatment costs. To overcome these limitations, peptide-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) were developed using the nanoprecipitation technique and were optimized via Box-Behnken Design (BBD) and Response Surface Methodology (RSM). Developed NPs were evaluated for potential toxicity and cell apoptosis using the zebrafish embryo toxicity (ZET) model with titanium dioxide NPs and ethanol (1% v/v) serving as positive controls. Developed NPs had a size of 75.6-153.8 nm, a polydispersity index between 0.11 and 0.25 and a zeta potential of -9.4 to -46.0 mV. Loaded peptide was found to be stable under various experimental conditions tested. BBD and RSM were validated through the characterization of optimized formulations. Survival and hatching rates of NP-treated zebrafish 0-144 h post-fertilization were found to be normal with no significant malformations. Cellular apoptosis studies also endorsed the non-cytotoxic nature of the NPs. The overall results indicate that optimized PLGA nanoparticles could be a promising platform for efficient peptide delivery to the posterior segment of the eye.


Assuntos
Portadores de Fármacos/toxicidade , Ácido Láctico/toxicidade , Nanopartículas/toxicidade , Peptídeos/administração & dosagem , Ácido Poliglicólico/toxicidade , Animais , Apoptose/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/efeitos adversos , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Injeções Intravítreas , Ácido Láctico/administração & dosagem , Ácido Láctico/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Peptídeos/química , Ácido Poliglicólico/administração & dosagem , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Testes de Toxicidade , Peixe-Zebra/embriologia
10.
J Dermatol Sci ; 89(1): 33-39, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29122406

RESUMO

BACKGROUND: Sensitive skin is a condition of cutaneous hypersensitivity to environmental factors. Lactic acid stinging test (LAST) is commonly used to assess sensitive skin and composed of four distinct sensations (pain, burning sensation, itch, and crawly feeling). A link between sensitive skin and barrier dysfunction has been proposed in atopic dermatitis (AD) patients. However, clinical and laboratory factors that are associated with sensitive skin remain unelucidated. OBJECTIVE: To investigate relationship between sensitive skin and AD-associated markers. METHODS: Forty-two Japanese AD patients and 10 healthy subjects (HS) were enrolled. AD patients were divided into extrinsic (EAD; high IgE levels) and intrinsic (IAD; normal IgE levels) types. We conducted 1% LAST by assessing the four distinct sensations and calculated the frequencies of sensitive skin in EAD, IAD, and HS. We also performed clinical AD-related tests, including transepidermal water loss (TEWL), visual analogue scale (VAS) of pruritus, and quality of life, and measured laboratory markers, including blood levels of IgE, CCL17/TARC, lactate dehydrogenase (LDH) and eosinophil counts, and concentration levels of serum Th1/Th2 cytokines. Filaggrin (FLG) mutations were examined in 21 patients. These values were subjected to correlation analyses with each of the four sensation elements. RESULTS: According to the standard criteria for LAST positivity, the frequencies of LAST-positive subjects were 54.8% and 10.0% in AD and HS, respectively (P=0.014). EAD patients showed a significantly (P=0.026) higher frequency of positive LAST (65.6%) than did IAD patients (20.0%). Among the four LAST sensation elements, the crawly feeling and pain scores positively correlated with VAS of pruritus, total serum IgE, mite-specific IgE, CCL17/TARC, and/or LDH. There was no association of the LAST scores with serum Th1/Th2 cytokine levels. Notably, neither TEWL nor FLG mutations correlated with LAST positivity or any sensation scores. CONCLUSIONS: The frequency of sensitive skin is higher in EAD than in IAD. Sensitive skin is associated with AD severity, but not necessarily with barrier condition.


Assuntos
Dermatite Atópica/imunologia , Pele/imunologia , Perda Insensível de Água/fisiologia , Adulto , Idoso , Biomarcadores/sangue , Citocinas/sangue , Dermatite Atópica/sangue , Dermatite Atópica/genética , Dermatite Atópica/patologia , Feminino , Humanos , Imunoglobulina E/sangue , Proteínas de Filamentos Intermediários/genética , Ácido Láctico/toxicidade , Masculino , Pessoa de Meia-Idade , Prurido/sangue , Prurido/genética , Prurido/imunologia , Prurido/patologia , Índice de Gravidade de Doença , Pele/fisiopatologia , Testes de Irritação da Pele/métodos
11.
Molecules ; 22(12)2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29186078

RESUMO

In response to the demand for new implant materials characterized by high biocompatibility and bioresorption, two prototypes of fibrous nanocomposite implants for osseous tissue regeneration made of a newly developed blend of poly(l-lactide-co-glycolide) (PLGA) and syntheticpoly([R,S]-3-hydroxybutyrate), PLGA/PHB, have been developed and fabricated. Afibre-forming copolymer of glycolide and l-lactide (PLGA) was obtained by a unique method of synthesis carried out in blocksusing Zr(AcAc)4 as an initiator. The prototypes of the implants are composed of three layers of PLGA or PLGA/PHB, nonwoven fabrics with a pore structure designed to provide the best conditions for the cell proliferation. The bioactivity of the proposed implants has been imparted by introducing a hydroxyapatite material and IGF1, a growth factor. The developed prototypes of implants have been subjected to a set of in vitro and in vivobiocompatibility tests: in vitro cytotoxic effect, in vitro genotoxicity and systemic toxicity. Rabbitsshowed no signs of negative reactionafter implantation of the experimental implant prototypes.


Assuntos
Implantes Absorvíveis , Regeneração Óssea , Hidroxibutiratos , Ácido Láctico/química , Ácido Láctico/farmacologia , Nanocompostos , Poliésteres , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacologia , Tecidos Suporte , Animais , Biomarcadores , Linhagem Celular , Sobrevivência Celular , Humanos , Hidroxibutiratos/química , Ácido Láctico/toxicidade , Camundongos , Nanocompostos/química , Poliésteres/química , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , Coelhos , Engenharia Tecidual
12.
Invest Ophthalmol Vis Sci ; 58(10): 4274-4285, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28850638

RESUMO

Purpose: Poly(lactic-co-glycolic) acid (PLGA) inserts have been successfully developed for the treatment of posterior eye disease as a means of reducing injection frequency of intravitreally administered therapeutics. PLGA microspheres are also of interest for the delivery of intravitreal drugs, since they offer the advantage of being easily injected without surgical procedures or large injectors. Methods: In the current study, the toxicity of PLGA microspheres and rods was investigated in nonhuman primates (NHPs) and rabbits. An in vitro assessment of cytokine responses to PLGA in peripheral blood mononuclear cells (PBMCs) and macrophages was also performed. Results: Intravitreal administration of 3, 10, or 12.5 mg/eye of PLGA microspheres in NHPs resulted in a severe immune response characterized by a foreign body response. Follow-up studies in the rabbit confirmed this finding for PLGA microspheres ranging in size from 20 to 100 µm. In contrast, administration of PLGA rod implants with a similar PLGA mass did not elicit a significant immune response. In vitro assays in PBMCs and macrophages confirmed proinflammatory cytokine release upon treatment with PLGA microspheres but not PLGA rods. Conclusions: These data demonstrate a lack of tolerability of PLGA microspheres upon intravitreal injection, and suggest that the size, shape, and/or surface area of PLGA depots are critical attributes in determining ocular toxicity.


Assuntos
Materiais Biocompatíveis/toxicidade , Sistemas de Liberação de Medicamentos/efeitos adversos , Ácido Láctico/toxicidade , Microesferas , Ácido Poliglicólico/toxicidade , Animais , Materiais Biocompatíveis/administração & dosagem , Citocinas/metabolismo , Modelos Animais de Doenças , Reação a Corpo Estranho/metabolismo , Reação a Corpo Estranho/patologia , Injeções Intravítreas , Ácido Láctico/administração & dosagem , Macrófagos/metabolismo , Ácido Poliglicólico/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Retina/efeitos dos fármacos , Retina/patologia , Corpo Vítreo/efeitos dos fármacos , Corpo Vítreo/patologia
13.
An Acad Bras Cienc ; 89(2): 1073-1084, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28640354

RESUMO

This study aimed to evaluate the teratogenic and hepatotoxic potential of the usnic acid encapsulated into PLGA-microspheres. In total, 12 female Wistar rats in pregnancy were randomly distributed in the control group (n= 6) that received 1.0 mL of physiological solution and treatment group (n= 6) that received 25 mg/kg of encapsulated usnic acid by oral administration. All females were euthanized at day 20 of pregnancy and their fetuses were removed and analyzed. During the pregnancy was observed a reduction in weight gain. There was no difference in serum transaminases levels analyzed as well as any difference in liver weight in both groups. The histomorphometric analysis of the liver from the treatment group revealed an increase in number of hepatocytes and a decrease in nuclear area of these cells. Moreover, no alteration was observed in cell area of hepatocytes or number of Kupffer cells. The fetuses had an increase in total number of hepatocytes and a reduction in the amount of megakaryocytes. These results show the hepatotoxic potential of usnic acid during pregnancy. However, its toxicity can be minimized by encapsulation in microspheres.


Assuntos
Ascomicetos/química , Benzofuranos/toxicidade , Feto/efeitos dos fármacos , Ácido Láctico/toxicidade , Líquens/química , Fígado/efeitos dos fármacos , Ácido Poliglicólico/toxicidade , Anormalidades Induzidas por Medicamentos , Animais , Benzofuranos/química , Feminino , Peso Fetal/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Ácido Láctico/química , Fígado/patologia , Exposição Materna , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Gravidez , Distribuição Aleatória , Ratos Wistar , Valores de Referência
14.
J Pharm Sci ; 106(8): 2106-2114, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28535975

RESUMO

Paclitaxel (PTX) incorporation in poly(lactic-co-glycolic acid) (PLGA) matrices produce films with high tensile rigidity and slow release that fail to deliver the required release rate for most biomedical applications such as in drug eluting stents and cancer treatments. To modify and improve this behavior, a set of poly(diol sebacate)s were synthesized and fully characterized as possible additives. The tensile properties of PLGA blends were evaluated as these materials could be used as coatings in drug eluting stent applications. A significant improvement in mechanical flexibility was observed with 20% additive content, as it reduced the Young's modulus value and increased the maximum deformation at break. PTX release was studied and correlated with the release of additive from PLGA films. An increase in the initial burst release phase was observed on all blends when compared to the control films of PLGA. Modulation of PTX release was achieved by altering the hydrophilicity degree of the additive or its percentage content on the blend. This supports the possibility that PTX was partitioned into the additive phase. Cytotoxicity analyses of novel additives were performed on mouse embryonic fibroblasts NIH/3T3.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Materiais Biocompatíveis/química , Ácidos Decanoicos/química , Ácidos Dicarboxílicos/química , Portadores de Fármacos/química , Ácido Láctico/química , Paclitaxel/administração & dosagem , Ácido Poliglicólico/química , Polímeros/química , Animais , Materiais Biocompatíveis/toxicidade , Ácidos Decanoicos/toxicidade , Ácidos Dicarboxílicos/toxicidade , Portadores de Fármacos/toxicidade , Módulo de Elasticidade , Ácido Láctico/toxicidade , Camundongos , Células NIH 3T3 , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/toxicidade
15.
Microvasc Res ; 112: 14-19, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28161429

RESUMO

Endothelial dysfunction is initial and critical step of atherosclerosis. Impaired bioavailability of endothelial nitric oxide synthase (eNOS) is one of the main reasons of endothelial dysfunction. Improving bioavailability of eNOS by increasing its expression or activity using statins is an effective therapeutic strategy in restoring endothelial dysfunction. In this study, simvastatin (SIM) as a poorly water-soluble drug was loaded in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (SIM-PLGA-NPs). NPs were then conjugated with mZD7349 peptide (mZD7349-SIM-PLGA-NPs) and directed against vascular cell adhesion molecule 1 (VCAM-1). In vitro evaluation of the NPs for targeted delivery of SIM was performed on activated Human Umbilical Cord Vascular Endothelial Cells (HUVECs) by tumor necrosis factor alpha (TNF-α). Effect of mZD7349-SIM-PLGA-NPs and SIM-PLGA-NPs was compared on eNOS phosphorylation (ser-1177). Results of western blot showed SIM post-treatment increased significantly phosphor-eNOS (Ser1177) expression but no total eNOS expression. The study showed that mZD7349-SIM-PLGA-NPs have particle size, zeta potential value, polydispersity index (PDI) and encapsulation efficacy % of 233±18nm, -9.6±1.1mV, 0.59±0.066 and 69±17.3%, respectively. Also phosphor-eNOS (Ser1177) expression in activated HUVECs treated with mZD7349-SIM-PLGA-NPs was significantly (p<0.05) better than treated cells with SIM-PLGA-NPs. The results suggest that mZD7349-SIM-PLGA-NPs may be usable as an appropriate drug carrier for restoring endothelial dysfunction.


Assuntos
Anti-Inflamatórios/farmacologia , Portadores de Fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inflamação/prevenção & controle , Ácido Láctico/química , Nanopartículas , Peptídeos Cíclicos/metabolismo , Ácido Poliglicólico/química , Sinvastatina/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/toxicidade , Células Cultivadas , Composição de Medicamentos , Liberação Controlada de Fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Inflamação/metabolismo , Inflamação/patologia , Ácido Láctico/toxicidade , Óxido Nítrico Sintase Tipo III/metabolismo , Peptídeos Cíclicos/química , Peptídeos Cíclicos/toxicidade , Fosforilação , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Serina , Sinvastatina/química , Sinvastatina/metabolismo , Sinvastatina/toxicidade , Solubilidade , Fatores de Tempo , Fator de Necrose Tumoral alfa/farmacologia
16.
Drug Deliv ; 24(1): 40-50, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28155565

RESUMO

Amphotericin B (AMB) is used most commonly in severe systemic life-threatening fungal infections. There is currently an unmet need for an efficacious (AMB) formulation amenable to oral administration with better bioavailability and lower nephrotoxicity. Novel PEGylated polylactic-polyglycolic acid copolymer (PLGA-PEG) nanoparticles (NPs) formulations of AMB were therefore studied for their ability to kill Candida albicans (C. albicans). The antifungal activity of AMB formulations was assessed in C. albicans. Its bioavalability was investigated in nine groups of rats (n = 6). Toxicity was examined by an in vitro blood hemolysis assay, and in vivo nephrotoxicity after single and multiple dosing for a week by blood urea nitrogen (BUN) and plasma creatinine (PCr) measurements. The MIC of AMB loaded to PLGA-PEG NPs against C. albicans was reduced two to threefold compared with free AMB. Novel oral AMB delivery loaded to PLGA-PEG NPs was markedly systemically available compared to Fungizone® in rats. The addition of 2% of GA to the AMB formulation significantly (p < 0.05) improved the bioavailability from 1.5 to 10.5% and the relative bioavailability was > 790% that of Fungizone®. The novel AMB formulations showed minimal toxicity and better efficacy compared to Fungizone®. No nephrotoxicity in rats was detected after a week of multiple dosing of AMB NPs based on BUN and PCr, which remained at normal levels. An oral delivery system of AMB-loaded to PLGA-PEG NPs with better efficacy and minimal toxicity was formulated. The addition of glycyrrhizic acid (GA) to AMB NPs formulation resulted in a significant oral absorption and improved bioavailability in rats.


Assuntos
Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Candida albicans/efeitos dos fármacos , Portadores de Fármacos , Ácido Láctico/química , Nanopartículas , Polietilenoglicóis/química , Ácido Poliglicólico/química , Administração Oral , Anfotericina B/química , Anfotericina B/farmacocinética , Anfotericina B/toxicidade , Animais , Antifúngicos/química , Antifúngicos/farmacocinética , Antifúngicos/toxicidade , Disponibilidade Biológica , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Candida albicans/crescimento & desenvolvimento , Creatinina/sangue , Composição de Medicamentos , Ácido Glicirrízico/administração & dosagem , Ácido Glicirrízico/química , Hemólise/efeitos dos fármacos , Nefropatias/sangue , Nefropatias/induzido quimicamente , Ácido Láctico/toxicidade , Testes de Sensibilidade Microbiana , Polietilenoglicóis/toxicidade , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley , Tecnologia Farmacêutica/métodos
17.
Int J Biol Macromol ; 95: 750-756, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27919818

RESUMO

Biocompatible and biodegradable polymers like PLGA have revolutionized the drug delivery approaches. However, poor drug loading and substantially high lipophilicity, pave a path for further tailing of this promising agent. In this regard, PLGA was feathered with biocompatible phospholipid and polymeric micelles were developed for delivery of Methotrexate (MTX) to cancer cells. The nanocarriers (114.6nm±5.5nm) enhanced the cytotoxicity of MTX by 2.13 folds on MDA-MB-231 cells. Confocal laser scanning microscopy confirmed the increased intracellular delivery. The carrier decreased the protein binding potential and enhanced the bioavailable fraction of MTX. Pharmacokinetic studies vouched substantial enhancement in AUC and bioresidence time, promising an ideal carrier to effectively deliver the drug to the site of action. The developed nanocarriers offer potential to deliver the drug in the interiors of cancer cells in an effective manner for improved therapeutic action.


Assuntos
Ácido Láctico/química , Ácido Láctico/metabolismo , Lecitinas/química , Metotrexato/química , Micelas , Ácido Poliglicólico/química , Ácido Poliglicólico/metabolismo , Soja/química , Animais , Transporte Biológico , Bovinos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Humanos , Ácido Láctico/farmacocinética , Ácido Láctico/toxicidade , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Soroalbumina Bovina/metabolismo
18.
FEMS Yeast Res ; 16(5)2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27381983

RESUMO

The ability of Zygosaccharomyces bailii to grow at low pH and in the presence of considerable amounts of weak organic acids, at lethal condition for Saccharomyces cerevisiae, increased the interest in the biotechnological potential of the yeast. To understand the mechanism of tolerance and growth effect of weak acids on Z. bailii, we evaluated the physiological and macromolecular changes of the yeast exposed to sub lethal concentrations of lactic acid. Lactic acid represents one of the important commodity chemical which can be produced by microbial fermentation. We assessed physiological effect of lactic acid by bioreactor fermentation using synthetic media at low pH in the presence of lactic acid. Samples collected from bioreactors were stained with propidium iodide (PI) which revealed that, despite lactic acid negatively influence the growth rate, the number of PI positive cells is similar to that of the control. Moreover, we have performed Fourier Transform Infra-Red (FTIR) microspectroscopy analysis on intact cells of the same samples. This technique has been never applied before to study Z. bailii under this condition. The analyses revealed lactic acid induced macromolecular changes in the overall cellular protein secondary structures, and alterations of cell wall and membrane physico-chemical properties.


Assuntos
Fermentação , Ácido Láctico/metabolismo , Ácido Láctico/toxicidade , Viabilidade Microbiana/efeitos dos fármacos , Estresse Fisiológico , Zygosaccharomyces/efeitos dos fármacos , Zygosaccharomyces/fisiologia , Anaerobiose , Reatores Biológicos/microbiologia , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Parede Celular/química , Parede Celular/efeitos dos fármacos , Parede Celular/fisiologia , Fenômenos Químicos , Meios de Cultura/química , Proteínas Fúngicas/química , Concentração de Íons de Hidrogênio , Propídio/análise , Conformação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier , Coloração e Rotulagem , Zygosaccharomyces/crescimento & desenvolvimento
19.
Biomed Res Int ; 2016: 4652876, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446952

RESUMO

D-lactate is a natural component of many fermented foods like yogurts, sour milk, cheeses, and pickles vegetable products. D-lactate in high concentrations is toxic for children and people with short bowel syndrome and provokes encephalopathy. These facts convincingly demonstrate a need for effective tools for the D-lactate removal from some food products. The main idea of investigation is focused on application of recombinant thermotolerant methylotrophic yeast Hansenula polymorpha "tr6," overproducing D-lactate: cytochrome c oxidoreductase (EC 1.1.2.4, D-lactate cytochrome c oxidoreductase, D-lactate dehydrogenase (cytochrome), DLDH). In addition to 6-fold overexpression of DLDH under a strong constitutive promoter (prAOX), the strain of H. polymorpha "tr6" (gcr1 catX/Δcyb2, prAOX_DLDH) is characterized by impairment in glucose repression of AOX promoter, devoid of catalase and L-lactate-cytochrome c oxidoreductase activities. Overexpression of DLDH coupling with the deletion of L-lactate-cytochrome c oxidoreductase activity opens possibility for usage of the strain as a base for construction of bioreactor for removing D-lactate from fermented products due to oxidation to nontoxic pyruvate. A laboratory prototype of column-type bioreactor for removing a toxic D-lactate from model solution based on permeabilized cells of the H. polymorpha "tr6" and alginate gel was constructed and efficiency of this process was tested.


Assuntos
Reatores Biológicos , Lactato Desidrogenases/genética , Ácido Láctico/toxicidade , Pichia/enzimologia , Encefalopatias/induzido quimicamente , Encefalopatias/patologia , Fermentação , Doenças Transmitidas por Alimentos/enzimologia , Doenças Transmitidas por Alimentos/genética , Glucose/química , Glucose/metabolismo , Lactato Desidrogenases/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo , Oxirredução , Pichia/genética
20.
IET Nanobiotechnol ; 10(3): 114-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27256889

RESUMO

Picroliv, a mixture of picroside I and kutkoside isolated from rhizome of Picrorrhiza kurroa has been reported for many pharmaceutical properties such as hepatoprotective, anticholestatic, antioxidant and immune-modulating activity. However, picroliv possessed lesser efficacy due to its poor aqueous solubility and lesser bioavailability. To find solution, picroliv was loaded into biodegradable poly lactic acid nanoparticles (PLA NPs) using solvent evaporation method. The picroliv-loaded PLA NPs were characterised by UV-vis spectroscopy, atomic force microscopy, transmission electron microscopy, Fourier transform infrared and Zeta sizer. The size of picroliv-loaded PLA NPs was 182 ± 20 nm. Zeta potential of picroliv-loaded PLA NPs was -23.5 mV, indicated their good stability. In vitro picroliv release from picroliv-loaded PLA NPs showed an initial burst release followed by slow and sustained release. The efficacy of picroliv-loaded PLA NPs was assessed against KB cell lines. Blank PLA NPs showed no cytotoxicity on KB cells. The picroliv-loaded PLA NPs showed more cytotoxic activity on KB cells as compared to the pure drug. Hence, the developed picroliv nanoformulation would find potential application in pharma-sector.


Assuntos
Cinamatos/química , Cinamatos/farmacocinética , Portadores de Fármacos/química , Glicosídeos/química , Glicosídeos/farmacocinética , Nanopartículas/química , Picrorhiza/química , Ácido Vanílico/química , Ácido Vanílico/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Cinamatos/isolamento & purificação , Cinamatos/toxicidade , Portadores de Fármacos/toxicidade , Glicosídeos/isolamento & purificação , Glicosídeos/toxicidade , Humanos , Células KB , Ácido Láctico/química , Ácido Láctico/toxicidade , Nanopartículas/toxicidade , Poliésteres , Polímeros/química , Polímeros/toxicidade , Ácido Vanílico/isolamento & purificação , Ácido Vanílico/toxicidade
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