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1.
Phys Chem Chem Phys ; 21(41): 22679-22694, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31595905

RESUMO

Peptide misfolding and aberrant assembly in membranous micro-environments have been associated with numerous neurodegenerative diseases. The biomolecular mechanisms and biophysical implications of these amyloid membrane interactions have been under extensive research and can assist in understanding disease pathogenesis and potential development of rational therapeutics. But, the complex nature and diversity of biomolecular interactions, structural transitions, and dependence on local environmental conditions have made accurate microscopic characterization challenging. In this review, using cases of Alzheimer's disease (amyloid-beta peptide), Parkinson's disease (alpha-synuclein peptide) and Huntington's disease (huntingtin protein), we illustrate existing challenges in experimental investigations and summarize recent relevant numerical simulation studies into amyloidogenic peptide-membrane interactions. In addition we project directions for future in silico studies and discuss shortcomings of current computational approaches.


Assuntos
Biologia Computacional , Lipídeos/química , Doenças Neurodegenerativas , Dobramento de Proteína , Proteínas Amiloidogênicas/metabolismo , Membrana Celular/metabolismo , Simulação por Computador , Humanos , Metabolismo dos Lipídeos , Doenças Neurodegenerativas/fisiopatologia , Peptídeos/metabolismo
2.
Adv Exp Med Biol ; 1161: 133-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31562628

RESUMO

Bioactive lipids, or lipid mediators, are utilized for intercellular communications. They are rapidly produced in response to various stimuli and exported to extracellular spaces followed by binding to cell surface G protein-coupled receptors (GPCRs) or nuclear receptors. Many drugs targeting lipid signaling such as non-steroidal anti-inflammatory drugs (NSAIDs), prostaglandins, and antagonists for lipid GPCRs are in use. For example, the sphingolipid analog, fingolimod (also known as FTY720), was the first oral disease-modifying therapy (DMT) for relapsing-remitting multiple sclerosis (MS), whose mechanisms of action (MOA) includes sequestration of pathogenic lymphocytes into secondary lymphoid organs, as well as astrocytic modulation, via down-regulation of the sphingosine 1-phosphate (S1P) receptor, S1P1, by in vivo-phosphorylated fingolimod. Though the cause of MS is still under debate, MS is considered to be an autoimmune demyelinating and neurodegenerative disease. This review summarizes the involvement of bioactive lipids (prostaglandins, leukotrienes, platelet-activating factors, lysophosphatidic acid, and S1P) in MS and the animal model, experimental autoimmune encephalomyelitis (EAE). Genetic ablation, along with pharmacological inhibition, of lipid metabolic enzymes and lipid GPCRs revealed that each bioactive lipid has a unique role in regulating immune and neural functions, including helper T cell (TH1 and TH17) differentiation and proliferation, immune cell migration, astrocyte responses, endothelium function, and microglial phagocytosis. A systematic understanding of bioactive lipids in MS and EAE dredges up information about understudied lipid signaling pathways, which should be clarified in the near future to better understand MS pathology and to develop novel DMTs.


Assuntos
Encefalomielite Autoimune Experimental , Metabolismo dos Lipídeos , Lipídeos , Esclerose Múltipla , Doenças Neurodegenerativas , Animais , Modelos Animais de Doenças , Lipídeos/química , Esclerose Múltipla/fisiopatologia , Doenças Neurodegenerativas/enzimologia , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/fisiopatologia
3.
Adv Exp Med Biol ; 1159: 5-31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31502197

RESUMO

Mitochondria and bacteria share a myriad of properties since it is believed that the powerhouses of the eukaryotic cell have evolved from a prokaryotic origin. Ribosomal RNA sequences, DNA architecture and metabolism are strikingly similar in these two entities. Proteins and nucleic acids have been a hallmark for comparison between mitochondria and prokaryotes. In this chapter, similarities (and differences) between mitochondrial and prokaryotic membranes are addressed with a focus on structure-function relationship of different lipid classes. In order to be suitable for the theme of the book, a special emphasis is reserved to the effects of bioactive sphingolipids, mainly ceramide, on mitochondrial membranes and their roles in initiating programmed cell death.


Assuntos
Evolução Biológica , Membrana Celular/química , Lipídeos/química , Mitocôndrias/química , Células Procarióticas/química , Ceramidas , Esfingolipídeos
4.
Adv Exp Med Biol ; 1161: 3-12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31562617

RESUMO

Keratitis is a sight-threatening inflammatory condition of the cornea that can be caused by both infectious and non-infectious agents. Physical or chemical trauma are typically related to non-infectious keratitis, which may then become secondarily infected or remain non-infected. Etiology of infectious keratitis is most often associated with bacteria; but viruses, fungi, and parasites are common causative pathogens as well. As a global concern, common risk factors include: systemic immunosuppression (secondary to malnutrition, alcoholism, diabetes, steroid use), previous corneal surgery (refractive corneal surgery, penetrating keratoplasty), extended wear contact lens use, pre-existing ocular surface diseases (dry eye, epithelial defect) and ocular trauma (agriculture- or farm-related) [1-8]. Annual rates of incidence include nearly one million clinical visits due to keratitis in the United States, while it has been reported that roughly two million people develop corneal ulcers in India. Clinically, patients may show signs of eye pain (ranging from mild to severe), blurred vision, photophobia, chemosis and redness. Pathogenesis is generally characterized by rapid progression, focal white infiltrates with underlying stromal inflammation, corneal thinning, stromal edema, mucopurulent discharge and hypopyon, which can lead to corneal scarring, endophthalmitis, and perforation. In fact, corneal opacity is not only a complication of keratitis, but among the leading causes of legal blindness worldwide. Despite that empirical treatment effectively controls most of the pathogens implicated in infectious keratitis, improved clinical outcomes are not guaranteed. Further, if treatment is not initiated in a timely manner, good visual outcome is reduced to approximately 50% of keratitis patients [9]. Moreover, resultant structural alterations, loss of tissue and an unresolved host response remain unaddressed through current clinical management of this condition.


Assuntos
Infecções Oculares , Ceratite , Metabolismo dos Lipídeos/fisiologia , Úlcera da Córnea/epidemiologia , Úlcera da Córnea/etiologia , Úlcera da Córnea/fisiopatologia , Infecções Oculares/complicações , Infecções Oculares/microbiologia , Infecções Oculares/parasitologia , Infecções Oculares/virologia , Humanos , Ceratite/epidemiologia , Ceratite/etiologia , Ceratite/microbiologia , Ceratite/fisiopatologia , Lipídeos/química , Estudos Retrospectivos
5.
Adv Exp Med Biol ; 1161: 193-217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31562631

RESUMO

Headache is a common complaint after mild traumatic brain injury (mTBI). Changes in the CNS lipidome were previously associated with acrolein-induced headache in rodents. mTBI caused similar headache-like symptoms in rats; therefore, we tested the hypothesis that mTBI might likewise alter the lipidome. Using a stereotaxic impactor, rats were given either a single mTBI or a series of 4 mTBIs 48 h apart. 72 h later for single mTBI and 7 days later for repeated mTBI, the trigeminal ganglia (TG), trigeminal nucleus (TNC), and cerebellum (CER) were isolated. Using HPLC/MS/MS, ~80 lipids were measured in each tissue and compared to sham controls. mTBI drove widespread alterations in lipid levels. Single mTBI increased arachidonic acid and repeated mTBI increased prostaglandins in all 3 tissue types. mTBI affected multiple TRPV agonists, including N-arachidonoyl ethanolamine (AEA), which increased in the TNC and CER after single mTBI. After repeated mTBI, AEA increased in the TG, but decreased in the TNC. Common to all tissue types in single and repeated mTBI was an increase the AEA metabolite, N-arachidonoyl glycine, a potent activator of microglial migration. Changes in the CNS lipidome associated with mTBI likely play a role in headache and in long-term neurodegenerative effects of repeated mTBI.


Assuntos
Lesões Encefálicas Traumáticas , Sistema Nervoso Central , Cefaleia , Inflamação , Lipídeos , Neoplasias , Animais , Lesões Encefálicas Traumáticas/fisiopatologia , Sistema Nervoso Central/fisiopatologia , Cefaleia/fisiopatologia , Inflamação/fisiopatologia , Lipídeos/química , Lipídeos/genética , Lipídeos/fisiologia , Neoplasias/fisiopatologia , Ratos
6.
J Agric Food Chem ; 67(38): 10614-10623, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31483658

RESUMO

Type 2 diabetes (T2D) is a pandemic disease chiefly characterized by hyperglycemia. In this study, the combination of serum lipidomic and metabolomic approach was employed to investigate the effect of arabinoxylan on type 2 diabetic rats and identify the critical biomarkers of T2D. Metabolomics analysis revealed that branched-chain amino acids, 12α-hydroxylated bile acids, ketone bodies, and several short- and long-chain acylcarnitines were significantly increased in T2D, whereas lysophosphatidylcholines (LPCs) were significantly decreased. Lipidomics analysis indicated T2D-related dyslipidemia was mainly associated with the increased levels of acetylcarnitine, free fatty acids (FFA), diacylglycerols, triacylglycerols, and cholesteryl esters and the decreased levels of some unsaturated phosphatidylcholines (less than 22 carbons). These variations indicated the disturbed amino acid and lipid metabolism in T2D, and the accumulation of incompletely oxidized lipid species might eventually contribute to impaired insulin action and glucose homeostasis. Arabinoxylan treatment decreased the concentrations of 12α-hydroxylated bile acids, carnitines, and FFAs and increased the levels of LPCs. The improved bile acid and lipid metabolism by arabinoxylan might be involved in the alleviation of hypercholesterolemia and hyperlipidemia in T2D.


Assuntos
Anticolesterolemiantes/administração & dosagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipercolesterolemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipolipemiantes/administração & dosagem , Xilanos/administração & dosagem , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Carnitina/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Glucose/metabolismo , Humanos , Hipercolesterolemia/etiologia , Hipercolesterolemia/metabolismo , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Metabolômica , Ratos
7.
J Agric Food Chem ; 67(39): 10984-10993, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31525294

RESUMO

The objective of the present study was to reveal the effects of four types of nitrogen sources (soymeal, yeast extract, KNO3, and ammonium tartrate) on the lipid metabolism of the oleaginous fungus Mortierella alpina using untargeted lipidomics, targeted fatty acid, and reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis. Our results showed clear differences in the contents and compositions of lipids between four types of nitrogen sources. Soymeal and ammonium tartrate supplementation favored the accumulation of triglycerides with arachidonic acid (ARA) and C16-18 fatty acids, respectively. These results were further validated by our targeted fatty acid analysis. RT-qPCR analysis of related genes in M. alpina between the four nitrogen source conditions found that soymeal supplementation dramatically increased the expression of GPAT, ELOVL, and Δ12/Δ6 desaturase. Our findings provided new insights into the regulation of lipid biosynthesis in M. alpina and potential avenues for genetic manipulation and highlighted the importance of an optimal nitrogen source for ARA-rich oil production.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lipídeos/biossíntese , Lipídeos/química , Espectrometria de Massas/métodos , Mortierella/metabolismo , Nitrogênio/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos/biossíntese , Ácidos Graxos/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mortierella/química , Mortierella/enzimologia , Mortierella/genética
8.
Chem Commun (Camb) ; 55(82): 12288-12291, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31524898

RESUMO

Here we present a set of fluorescent cages prepared by tethering fluorescent dyes to a photolabile group. The developed molecules enable caging of signalling lipids, their delivery to specific cellular membranes, with further imaging, quantification, and controlled photorelease of active lipids in living cells.


Assuntos
Corantes Fluorescentes/química , Metabolismo dos Lipídeos , Lipídeos/química , Nitrobenzenos/química , Transdução de Sinais , Membrana Celular/química , Células HeLa , Humanos
9.
J Agric Food Chem ; 67(40): 11210-11218, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31512471

RESUMO

The aim of this work was to provide recent fatty acid (FA) profiling of chocolates and chocolate products, principally C18:1 trans FAs (TFAs). Thirty-two samples were analyzed by gas chromatography and FAs were quantified. The total TFA content declared in chocolate labeling and the real TFA content were compared. The TFA content ranged from 0.04 to 2.51 g/100 g of sample, and it was noticed that several manufacturers were underestimating the total TFA content in their labeling. The main TFA isomers quantified were C18:1 trans-9 (0.006-0.244%), C18:1 trans-10 (0.009-0.392%), and C18:1 trans-11 (0.013-0.464%), expressed in g/100 g of sample. Principal component analysis was used to discriminate industrial fats from natural trans fats based on the isomeric TFA profile and dairy fat (DF) biomarkers allowing to group samples in four clusters: high TFA content and high DF content, high TFA content and low DF content, low TFA content and high DF content, and low TFA content and low DF content.


Assuntos
Chocolate/análise , Lipídeos/química , Ácidos Graxos Trans/química , Brasil , Rotulagem de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Isomerismo
10.
Int J Nanomedicine ; 14: 5073-5085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371948

RESUMO

Purpose: To potentiate the anticancer activity of curcumin (CUR) by improving its cell penetration potentials through formulating it into nanostructured lipid carriers (NLCs) and using the prepared NLCs in photodynamic therapy. Methods: A 3×4 factorial design was used to obtain 12 CUR-NLCs using two factors on different levels: (1) the solid lipid type at four levels and (2) the solid to liquid lipid ratio at three levels. Olive oil, Tween 80 and lecithin were chosen as liquid lipid, surfactant and co-surfactant, respectively. CUR-NLCs prepared by high shear hot homogenization method were evaluated by determination of particle size (PS), polydispersity index, zeta potential (ZP), entrapment efficiency percent, drug loading percent and in vitro drug release. Optimization was based on the evaluation results using response surface modeling (RSM). Optimized formulae were tested for their in vitro release pattern and for dark and photo-cytotoxic anticancer activity on breast cancer cell line in comparison to free CUR. Results: Evaluation tests showed the appropriateness of NLCs prepared from glyceryl monooleate and Geleol™ helped choosing two optimized formulae, PE3 and GE3. PE3 (prepared using glyceryl monooleate) showed enhanced release rates compared to GE3 (prepared from Geleol) and superior cytotoxic anticancer activity compared to both GE3 and free CUR under both light and dark conditions. The small mean PS, spherical shape as well as the negative ZP enhanced the internalization of the NLCs within cells. Modulation and inhibition of P-glycoprotein expression by glyceryl monooleate synergized the cytotoxic activity of CUR. Conclusion: CUR loading in NLCs enhanced its cell penetration and cytotoxic anticancer properties both in dark and in light conditions.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Curcumina/uso terapêutico , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Ácidos Oleicos/química , Azeite de Oliva/química , Fotoquimioterapia , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática
11.
Int J Nanomedicine ; 14: 5381-5396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409994

RESUMO

Background: Tacrolimus (TCR), also known as FK-506, is a biopharmaceutics classification system (BCS) class II drug that is insoluble in water because of its high log P values. After dermal application, TCR remains in the stratum corneum and passes through the skin layers with difficulty. Purpose: The objectives of this study were to develop and evaluate solid lipid nanoparticles (SLNs) with thermosensitive properties to improve penetration and retention. Methods: We prepared TCR-loaded thermosensitive solid lipid nanoparticles (TCR-SLNs) with different types of surfactants on the shell of the particle, which conferred the advantages of enhancing skin permeation and distribution. We also characterized them from a physic point of view and performed in vitro and in vivo evaluations. Results: The TCR contained in the prepared TCR-SLN was in an amorphous state and entrapped in the particles with a high loading efficiency. The assessment of ex vivo skin penetration using excised rat dorsal skin showed that the TCR-SLNs penetrated to a deeper layer than the reference product (0.1% Protopic®). In addition, the in vivo skin penetration test demonstrated that TCR-SLNs delivered more drug into deeper skin layers than the reference product. FT-IR images also confirmed drug distribution of TCR-SLNs into deeper layers of the skin. Conclusion: These results revealed the potential application of thermosensitive SLNs for the delivery of difficult-to-permeate, poorly water-soluble drugs into deep skin layers.


Assuntos
Derme/metabolismo , Lipídeos/química , Nanopartículas/química , Tacrolimo/farmacologia , Temperatura Ambiente , Administração Cutânea , Animais , Varredura Diferencial de Calorimetria , Derme/efeitos dos fármacos , Liberação Controlada de Fármacos , Irritantes/toxicidade , Nanopartículas/ultraestrutura , Tamanho da Partícula , Coelhos , Ratos Sprague-Dawley , Absorção Cutânea/efeitos dos fármacos , Testes Cutâneos , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química , Difração de Raios X
12.
Int J Nanomedicine ; 14: 5201-5213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371956

RESUMO

Background: SN38 (7-ethyl-10-hydroxy camptothecin), as a potent metabolite of irinotecan, is highly efficacious in cancer treatment. However, the clinical utility of SN38 has been greatly limited due to its undesirable properties, such as poor solubility and low stability. Materials and methods: In order to overcome these weaknesses, moeixitecan, a lipophilic SN38 prodrug containing a SN-38, a trolox, a succinic acid linker, and a hexadecanol chain, was loaded into liposomal nanoparticles by ethanol injection method. Results: Experiments showed that the moeixitecan-loaded liposomal nanoparticles (MLP) with a diameter of 105.10±1.49 nm have a satisfactory drug loading rate (90.54±0.41%), high solubility and stability, and showed sustained release of SN38. Notably, MLP exhibited better antitumor activity against human colon adenocarcinoma cells than irinotecan, a FDA-approved drug for the treatment of advanced colorectal cancer. Furthermore, xenograft model results showed that MLP outperformed irinotecan in terms of pharmacokinetics, in vivo therapeutic efficacy and safety. Finally, we used molecular dynamic simulations to explore the association between the structure of MLP and the physical and functional properties of MLP, moeixitecan molecules in MLP folded themselves inside the hydrocarbon chain of the lipid bilayer, which led an increased acyl chain order of the lipid bilayer, and therefore enhanced the lactone ring stability protecting it from hydrolysis. Conclusion: Our MLP constructing strategy by liposome engineering technology may serve a promising universal approach for the effective and safe delivery of lipophilic prodrug.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Irinotecano/uso terapêutico , Lipídeos/química , Pró-Fármacos/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Células HT29 , Humanos , Irinotecano/sangue , Irinotecano/farmacocinética , Lipossomos , Camundongos Nus , Simulação de Dinâmica Molecular , Nanopartículas/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Ratos Sprague-Dawley , Solubilidade , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Pharm Res ; 36(10): 145, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31396764

RESUMO

PURPOSE: The immediate plasma metabolism and development of chemo-resistance (single agent) severely hampers the clinical effectiveness of Sorafenib (SRF) in liver cancer therapy. MicroRNA27a inhibition is a promising biological strategy for breast cancer therapy. METHODS: In this study, we aimed to prepare SRF and anti-miRNA27a-loaded anti-GPC3 antibody targeted lipid nanoparticles to enhance the therapeutic efficacy against liver cancers. In this study, we have employed a unique cationic switchable lipid (CSL) as a mean to encapsulate miRNA as well as to confer pH-responsiveness to the nanocarrier system. RESULTS: The G-S27LN was nanosized and offered a pH-responsive release of SRF from the carrier system and we have demonstrated the specific affinity of G-S27LN towards the GPC3-overexpressed HepG2 cancer cells. Anti-microRNA27a significantly increased the protein expression of FOXO1 and PPAR-γ which are crucial components involved in proliferation and apoptosis of tumor cells. Combination of SRF and anti-miRNA27a (G-S27LN) resulted in significantly lower cell viability with a marked increase in the apoptosis cell proportion compared to that of free SRF indicating the synergistic anticancer effect. Animal studies in liver cancer xenograft model demonstrated significant suppression of tumor burden, reduced tumor cell and elevated TUNEL positive apoptosis with no toxicity concerns in animals treated with G-S27LN formulation. CONCLUSION: The CSL-based G-S27LN efficiently co-delivered anti-microRNA27a and SRF and therefore represents a promising therapy to treat liver cancer. This study also brings forth a platform strategy for the effective treatment of number of other advanced cancers.


Assuntos
Antagomirs/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Glipicanas/imunologia , Lipídeos/química , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/imunologia , Nanopartículas/química , Sorafenibe/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Sinergismo Farmacológico , Proteína Forkhead Box O1/metabolismo , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Camundongos Nus , PPAR gama/metabolismo , Fosforilcolina/química , Polietilenoglicóis/química
14.
Eur J Histochem ; 63(3)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31455073

RESUMO

RNA interference is a powerful approach to understand gene function both for therapeutic and experimental purposes. Since the lack of knowledge in the gene silencing of various hepatic cell lines, this work was aimed to compare two transfection agents, the liposome-based Lipofectamine™ RNAiMAX and the HepG2-specific, polymer-based GenMute™, in two cellular models of human hepatoma, HepG2 and Huh7.5. In the first part, we assessed transfection efficiency of a fluorescent Cy3-labeled negative control siRNA by cell imaging analysis; we found that cells treated with GenMute present a higher uptake of the fluorescent negative control siRNA when compared to Lipofectamine RNAiMAX-transfected cells, both in HepG2 and in Huh7.5 cells. In the second part, we evaluated GAPDH silencing with the two transfection reagents by RT-PCR similar GAPDH mRNA expression after each transfection treatment. Finally, we measured cell viability by the MTT assay, observing that cells transfected with GenMute have higher viability with respect to Lipofectamine RNAiMAX-administered cells. These results suggest that GenMute reagent might be considered the most suitable transfection agent for hepatic gene silencing.


Assuntos
Técnicas de Transferência de Genes , Lipídeos/química , Polímeros/química , RNA Interferente Pequeno/genética , Transfecção/métodos , Sequência de Bases , Carbocianinas/química , Carbocianinas/metabolismo , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Inativação Gênica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Metabolismo dos Lipídeos , Lipídeos/toxicidade , Lipossomos/química , Lipossomos/metabolismo , Lipossomos/toxicidade , Neoplasias Hepáticas/genética , Polímeros/metabolismo , Polímeros/toxicidade , Interferência de RNA
15.
Pharm Res ; 36(10): 142, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376020

RESUMO

BACKGROUND: With the recent approval of the first small interfering RNA (siRNA) therapeutic formulated as nanoparticles, there is increased incentive for establishing the factors of importance for the design of stable solid dosage forms of such complex nanomedicines. METHODS: The aims of this study were: (i) to identify factors of importance for the design of spray-dried siRNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles (LPNs), and (ii) to evaluate their influence on the resulting powders by using a quality-by-design approach. Critical formulation and process parameters were linked to critical quality attributes (CQAs) using design of experiments, and an optimal operating space (OOS) was identified. RESULTS: A series of CQAs were identified based on the quality target product profile. The loading (ratio of LPNs to the total solid content) and the feedstock concentration were determined as critical parameters, which were optimized systematically. Mannitol was chosen as stabilizing excipient due to the low water content of the resulting powders. The loading negatively affected the colloidal stability of the LPNs, whereas feedstock concentration correlated positively with the powder particle size. The optimal mannitol-based solid formulation, defined from the OOS, displayed a loading of 5% (w/w), mass median aerodynamic diameter of 3.3 ± 0.2 µm, yield of 60.6 ± 6.6%, and a size ratio of 1.15 ± 0.03. Dispersed micro-embedded LPNs had preserved physicochemical characteristics as well as in vitro siRNA release profile and gene silencing, as compared to non-spray-dried LPNs. CONCLUSION: The optimal solid dosage forms represent robust formulations suitable for higher scale-up manufacturing.


Assuntos
Dessecação/métodos , Lipídeos/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , RNA Interferente Pequeno/química , Administração por Inalação , Animais , Composição de Medicamentos , Excipientes/química , Inativação Gênica , Técnicas de Transferência de Genes , Manitol/química , Camundongos , Nanomedicina , Tamanho da Partícula , Pós , Células RAW 264.7 , RNA Interferente Pequeno/administração & dosagem , Solubilidade , Solventes/química
16.
J Agric Food Chem ; 67(33): 9432-9440, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31368703

RESUMO

Potassium fertilization is commonly practiced in oil palm (Elaeis guineensis) plantations to increase yield. However, its effects on fruit oil content and composition are not well documented. Here, we conducted bunch, metabolomics, and oil composition analyses in two contrasting crosses (Deli × La Mé and Deli × Yangambi) grown under different K fertilization conditions. K availability impacted bunch oil content, resulting in lower water content and higher oil proportion in fruit mesocarp, in Deli × La Mé only, thus showing differential responses of crosses to K. Oil composition at maturity did not significantly change under low K conditions despite clear alterations in fruit metabolism associated with lipid production during maturation, demonstrating the resilience of oil biosynthetic metabolism. However, the analysis of variance in oil content (across K treatments and crosses) demonstrates that sugar availability, lipid synthesis rates, and metabolic recycling are all important in determining the oil content.


Assuntos
Arecaceae/metabolismo , Fertilizantes/análise , Frutas/química , Lipídeos/química , Óleo de Palmeira/química , Potássio/metabolismo , Arecaceae/química , Arecaceae/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Metabolismo dos Lipídeos
17.
J Chem Ecol ; 45(8): 673-683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407198

RESUMO

Animals modulate intraspecific signal shape and intensity, notably during reproductive periods. Signal variability typically follows a seasonal scheme, traceable through the expression of visual, acoustic, chemical and behavioral patterns. The chemical channel is particularly important in lizards, as demonstrated by well-developed epidermal glands in the cloacal region that secrete lipids and proteins recognized by conspecifics. In males, the seasonal pattern of gland activity is underpinned by variation of circulating androgens. Changes in the composition of lipid secretions convey information about the signaler's quality (e.g., size, immunity). Presumably, individual identity is associated with a protein signature present in the femoral secretions, but this has been poorly investigated. For the first time, we assessed the seasonal variability of the protein signal in relation to plasma testosterone level (T), glandular activity and the concentration of provitamin D3 in the lipid fraction. We sampled 174 male common wall lizards (Podarcis muralis) over the entire activity season. An elevation of T was observed one to two months before the secretion peak of lipids during the mating season; such expected delay between hormonal fluctuation and maximal physiological response fits well with the assumption that provitamin D3 indicates individual quality. One-dimensional electrophoretic analysis of proteins showed that gel bands were preserved over the season with an invariant region; a result in agreement with the hypothesis that proteins are stable identity signals. However, the relative intensity of bands varied markedly, synchronously with that of lipid secretion pattern. These variations of protein secretion suggest additional roles of proteins, an issue that requires further studies.


Assuntos
Glândulas Exócrinas/metabolismo , Lipídeos/análise , Lagartos/fisiologia , Proteínas de Répteis/análise , Animais , Desidrocolesteróis/análise , Eletroforese em Gel de Campo Pulsado , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo dos Lipídeos , Lipídeos/química , Masculino , Análise de Componente Principal , Estações do Ano , Comportamento Sexual Animal , Testosterona/sangue
18.
Int J Nanomedicine ; 14: 5555-5567, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413562

RESUMO

Background: Vinpocetine (VPN) is a synthetic derivative of the Vinca minor alkaloids. The drug is characterized by a short half-life, limited water solubility and high hepatic first-pass effect. The objective was to develop different lipid-based nanocarriers (NCs) loaded into a thermosensitive in situ gelling (ISG) system to improve VPN bioavailability and brain targeting via intranasal (IN) delivery. Methods:  Different lipid-based NCs were developed and characterized for vesicle size, zeta potential, VPN entrapment efficiency (EE) and morphological characterization using transmission electron microscope (TEM). The prepared NCs were loaded into ISG formulations and characterized for their mucoadhesive properties. Ex-vivo permeation and histological study of the nasal mucosa were conducted. Pharmacokinetic and brain tissue distribution were investigated and compared to a marketed VPN product following administration of a single dose to rats. Results: VPN-D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) micelles nano-formulation showed the smallest particle size, highest EE among the studied NCs. TEM images revealed an almost spherical shape for all the prepared NCs. Among the NCs studied, VPN-loaded TPGS micelles demonstrated the highest percent cumulative VPN ex vivo permeation. All the prepared ISG formulations revealed the presence of mucoadhesive properties and showed no signs of inflammation or necrosis upon histological examination. Rats administered IN VPN-loaded TPGS-micelles ISG showed superior VPN concentration in the brain tissue and significant high relative bioavailability when compared to that received raw VPN-loaded ISG and marketed drug oral tablets. VPN-D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) micelles nano-formulation showed the smallest particle size, highest EE among the studied NCs. TEM images revealed an almost spherical shape for all the prepared NCs. Among the NCs studied, VPN-loaded TPGS micelles demonstrated the highest percent cumulative VPN ex vivo permeation. All the prepared ISG formulations revealed the presence of mucoadhesive properties and showed no signs of inflammation or necrosis upon histological examination. Rats administered IN VPN-loaded TPGS-micelles ISG showed superior VPN concentration in the brain tissue and significant high relative bioavailability when compared to that received raw VPN-loaded ISG and marketed drug oral tablets. Conclusion: VPN-loaded TPGS-micelles ISG formulation is a successful brain drug delivery system with enhanced bioavailability for drugs with poor bioavailability and those that are frequently administered.


Assuntos
Géis/administração & dosagem , Micelas , Temperatura Ambiente , Alcaloides de Vinca/administração & dosagem , Vitamina E/química , Administração Intranasal , Animais , Disponibilidade Biológica , Encéfalo/metabolismo , Bovinos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Lipídeos/química , Masculino , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Sprague-Dawley , Solubilidade , Distribuição Tecidual , Alcaloides de Vinca/sangue , Alcaloides de Vinca/farmacocinética
19.
Food Chem ; 298: 125002, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260958

RESUMO

Lipids are only minor wheat flour constituents but play major roles in bread making (BM). Here, the importance of a well-balanced lipid population in BM was studied by applying a lipase from Fusarium oxysporum in the process. Monogalactosyldiacylglycerols and N-acyl phosphatidylethanolamines were the most accessible lipase substrates. Hydrolysis thereof into their corresponding lysolipids was largely if not entirely responsible for loaf volume increases upon lipase application. Degradation of endogenously present lipids and enzymatically released lysolipids caused loaf volume to decrease, confirming that an appropriate balance between different types of lipids is crucial in BM. For optimal dough gas cell stability, the level of lipids promoting lamellar mesophases and, thus, liquid condensed monolayers needs to be maximal while maintaining an appropriate balance between lipids promoting hexagonal I phases, non-polar lipids and lipids promoting hexagonal II or cubic phases.


Assuntos
Pão , Farinha , Lipase/metabolismo , Lipídeos/química , Triticum , Fermentação , Fusarium/enzimologia , Galactolipídeos/química , Galactolipídeos/metabolismo , Hidrólise , Lipase/química , Lisofosfolipídeos/química , Lisofosfolipídeos/metabolismo , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/metabolismo , Triticum/química , Triticum/metabolismo
20.
Food Chem ; 298: 125029, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260974

RESUMO

Thermal processing methods have important effects on food lipids. In this work, ultra-high-performance liquid chromatography-Q-Extractive Orbitrap mass spectrometry and lipidsearch software were applied to analyze effect of three types of thermal processing methods on the lipidomics profile of tilapia fillets. A total 15 classes of compound lipids (Cer, DG, LPC, LPE, LPG, LPI, LPS, PC, PE, PG, PI, PS, SM, So, TG) were analyzed. In addition, free DHA, EPA, and ARA were also identified. Furthermore, statistical analyses of these lipids were performed based on MetaboAnalyst software. The results demonstrated three types of thermal processing methods had different effects on lipidomics profile differences of tilapia fillets. A total of eight lipid species variables (LPS, LPG, LPI, DG, LPC, TG, LPE, and Cer) and 137 individual lipids variables showed significant differences among raw, steamed, boiled, and roasted tilapia fillets. This work could provide useful information for aquatic product processing and lipidomics.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Indústria de Processamento de Alimentos/métodos , Lipídeos/química , Tilápia , Animais , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/estatística & dados numéricos , Lipídeos/análise , Espectrometria de Massas/métodos
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