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1.
Carbohydr Polym ; 237: 116114, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32241406

RESUMEN

To extend the applications of natural products in nanomedicine, novel cellulose-based supramolecular nanoparticles (SNPs) were fabricated via a host-guest driven self-assembly strategy here. The adamantane-grafted carboxyethyl hydroxyethyl cellulose and ß-cyclodextrin-grafted glycerol ethoxylate were synthesized to self-assemble into the SNPs. Furthermore, doxorubicin (DOX)-functionalized ß-cyclodextrin was encapsulated into SNPs via an in situ co-assembly process to generate DOX-loaded SNPs (DOX-SNPs). The SNPs exhibited a quasi-spherical morphology with an average diameter of ∼25 nm. The DOX-SNPs with relatively larger diameter possessed a high DOX loading efficiency (∼94 %) and the pH-responsive drug release behaviors, which made them suitable as a drug delivery system. In vitro cytotoxicity assays demonstrated the excellent cytocompatibility of SNPs and the efficient inhibition of Hela cell proliferation of DOX-SNPs. Moreover, the DOX-SNPs could effectively enter Hela cells via endocytosis and release DOX under endo/lysosome pH. Thus, this nanocarrier has promising translational potential in cancer therapy and personalized nanomedicine.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Portadores de Fármacos , Nanopartículas , Adamantano/química , Materiales Biocompatibles , Celulosa/análogos & derivados , Celulosa/química , Portadores de Fármacos/síntesis química , Portadores de Fármacos/farmacología , Liberación de Fármacos , Éteres de Glicerilo/química , Células HeLa , Humanos , Nanomedicina , Nanopartículas/química , beta-Ciclodextrinas/química
2.
Int J Pharm ; 575: 118935, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31816353

RESUMEN

Novel liquid crystal nanoparticles (LCNs) composed of isostearyl glyceryl ether (GE-IS) and ethoxylated hydrogenated castor oil (HCO-60) were developed for the enhanced transdermal delivery of 4-biphenyl acetic acid (BAA). The physical properties and pharmaceutical properties of the LCNs were measured. The interaction between the intercellular lipid model of the stratum corneum and the LCNs was observed to elucidate the skin permeation mechanism. In the formulation, the LCNs form niosomes with mean particles sizes of 180-300 nm. The skin absorption mechanisms of LCNs are different, depending upon the application and buffer concentration. The LCNs composed of GE-IS and HCO-60 are attractive tools for use as transdermal drug delivery systems carriers for medicines and cosmetics, due to their high efficiency and safety.


Asunto(s)
Sistemas de Liberación de Medicamentos , Éteres de Glicerilo/administración & dosificación , Cristales Líquidos , Nanopartículas/administración & dosificación , Fenilacetatos/administración & dosificación , Administración Cutánea , Animales , Aceite de Ricino/administración & dosificación , Aceite de Ricino/química , Liberación de Fármacos , Éteres de Glicerilo/química , Humanos , Técnicas In Vitro , Cristales Líquidos/química , Masculino , Ratones Pelados , Nanopartículas/química , Fenilacetatos/química , Piel/metabolismo , Absorción Cutánea , Pruebas de Irritación de la Piel
3.
Adv Exp Med Biol ; 1161: 77-88, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31562623

RESUMEN

The Cyclooxygenase enzymes (COX-1 and COX-2) incorporate 2 molecules of O2 into arachidonic acid (AA), resulting in an array of bioactive prostaglandins. However, much work has been done showing that COX-2 will perform this reaction on several different AA-containing molecules, most importantly, the endocannabinoid 2-arachidonoylglycerol (2-AG). The products of 2-AG oxygenation, prostaglandin glycerol esters (PG-Gs), are analogous to canonical prostaglandins. This chapter reviews the literature detailing the production, metabolism, and bioactivity of these compounds, as well as their detection in intact animals.


Asunto(s)
Éteres de Glicerilo , Prostaglandinas , Animales , Ácidos Araquidónicos/metabolismo , Ciclooxigenasa 2/metabolismo , Endocannabinoides/metabolismo , Glicéridos/metabolismo , Éteres de Glicerilo/análisis , Éteres de Glicerilo/química , Éteres de Glicerilo/metabolismo , Prostaglandinas/análisis , Prostaglandinas/química , Prostaglandinas/metabolismo
4.
Int J Syst Evol Microbiol ; 69(7): 1892-1902, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30938665

RESUMEN

Two mesophilic, neutrophilic and aerobic marine ammonia-oxidizing archaea, designated strains NF5T and D3CT, were isolated from coastal surface water of the Northern Adriatic Sea. Cells were straight small rods 0.20-0.25 µm wide and 0.49-2.00 µm long. Strain NF5T possessed archaella as cell appendages. Glycerol dibiphytanyl glycerol tetraethers with zero to four cyclopentane moieties (GDGT-0 to GDGT-4) and crenarchaeol were the major core lipids. Menaquinone MK6 : 0 was the major respiratory quinone. Both isolates gained energy by oxidizing ammonia (NH3) to nitrite (NO2-) and used bicarbonate as a carbon source. Strain D3CT was able use urea as a source of ammonia for energy production and growth. Addition of hydrogen peroxide (H2O2) scavengers (catalase or α-keto acids) was required to sustain growth. Optimal growth occurred between 30 and 32 °C, pH 7.1 and 7.3 and between 34 and 37‰ salinity. The cellular metal abundance ranking of both strains was Fe>Zn>Cu>Mn>Co. The genomes of strains NF5T and D3CT have a DNA G+C content of 33.4 and 33.8 mol%, respectively. Phylogenetic analyses of 16S rRNA gene sequences revealed that both strains are affiliated with the class Nitrososphaeria, sharing ~85 % 16S rRNA gene sequence identity with Nitrososphaera viennensis EN76T. The two isolates are separated by phenotypic and genotypic characteristics and are assigned to distinct species within the genus Nitrosopumilus gen. nov. according to average nucleotide identity thresholds of their closed genomes. Isolates NF5T (=JCM 32270T =NCIMB 15114T) and D3CT (=JCM 32271T =DSM 106147T =NCIMB 15115T) are type strains of the species Nitrosopumilusadriaticus sp. nov. and Nitrosopumiluspiranensis sp. nov., respectively.


Asunto(s)
Amoníaco/metabolismo , Archaea/clasificación , Filogenia , Agua de Mar/microbiología , Archaea/aislamiento & purificación , Composición de Base , ADN de Archaea/genética , Éteres de Glicerilo/química , Peróxido de Hidrógeno , Océanos y Mares , Oxidación-Reducción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Methods Mol Biol ; 1949: 307-324, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30790264

RESUMEN

For uncompromised in vitro assays for intermembrane lipid transfer and membrane fusion fluorescent membrane-spanning lipids have proved to be invaluable tools. These lipids in contrast to phosphoglycerolipids and sphingolipids are resistant to spontaneous as well as protein-mediated intermembrane transfer. Here I describe the synthesis of some homo-substituted fluorescent bipolar membrane-spanning lipids that bear a fluorescent tag either directly or via a phosphoethanolamine spacer to the lipid core. For the synthesis the lipid core of the bipolar membrane-spanning lipids, i.e., the tetraether lipid caldarchaeol, is prepared from cultures of the archaea Thermoplasma acidophilum.


Asunto(s)
Membrana Celular/metabolismo , Metabolismo de los Lípidos , Fusión de Membrana , Lípidos de la Membrana/metabolismo , Archaea/metabolismo , Membrana Celular/química , Etanolaminas/química , Etanolaminas/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Éteres de Glicerilo/química , Éteres de Glicerilo/metabolismo , Liposomas , Lípidos de la Membrana/química
6.
Langmuir ; 35(9): 3568-3575, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30720282

RESUMEN

Monoglycerides are esterified adducts of fatty acid and glycerol molecules that disrupt phospholipid membranes, leading to a wide range of biological functions such as antimicrobial activity. Among monoglycerides, glycerol monolaurate (GML) exhibits particularly high antimicrobial activity, although enzymatic hydrolysis of its ester group can diminish potency. Consequently, there have been efforts to identify more chemically stable versions of GML, most notably its alkylglycerol ether equivalent called dodecylglycerol (DDG). However, despite high structural similarity, biological studies indicate that DDG and GML are not functionally equivalent and it has been speculated that the two compounds might have different interaction profiles with phospholipid membranes. To address this outstanding question, herein, we employed supported lipid bilayer (SLB) platforms to experimentally characterize the interactions of DDG with phospholipid membranes. Quartz crystal microbalance-dissipation experiments identified that DDG causes concentration-dependent membrane morphological changes in SLBs and the overall extent of membrane remodeling events was greater than that caused by GML. In addition, time-lapsed fluorescence microscopy imaging experiments revealed that DDG causes extensive membrane tubulation that is distinct from how GML induces membrane budding. We discuss how differences in the head group properties of DDG and GML contribute to distinct membrane interaction profiles, offering insight into how the molecular design of DDG not only improves chemical stability but also enhances membrane-disruptive activity.


Asunto(s)
Membrana Celular/efectos de los fármacos , Éteres de Glicerilo/farmacología , Lauratos/farmacología , Membrana Dobles de Lípidos/química , Monoglicéridos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Éteres de Glicerilo/química , Éteres de Glicerilo/toxicidad , Humanos , Lauratos/química , Lauratos/toxicidad , Microscopía Fluorescente , Monoglicéridos/química , Monoglicéridos/toxicidad , Fosfatidilcolinas/química , Tecnicas de Microbalanza del Cristal de Cuarzo
7.
PLoS One ; 13(12): e0208067, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30513093

RESUMEN

Archaeosomes are liposomes traditionally comprised of total polar lipids (TPL) or semi-synthetic glycerolipids of ether-linked isoprenoid phytanyl cores with varied glyco- and amino-head groups. As adjuvants, they induce robust, long-lasting humoral and cell-mediated immune responses and enhance protection in murine models of infectious disease and cancer. Traditional total polar lipid (TPL) archaeosome formulations are relatively complex and first generation semi-synthetic archaeosomes involve many synthetic steps to arrive at the final desired glycolipid composition. We have developed a novel archaeosome formulation comprising a sulfated disaccharide group covalently linked to the free sn-1 hydroxyl backbone of an archaeal core lipid (sulfated S-lactosylarchaeol, SLA) that can be more readily synthesized yet retains strong immunostimulatory activity for induction of cell-mediated immunity following systemic immunization. Herein, we have evaluated the immunostimulatory effects of SLA archaeosomes when used as adjuvant with ovalbumin (OVA) and hepatitis B surface antigen (HBsAg) and compared this to various other adjuvants including TLR3/4/9 agonists, oil-in-water and water-in-oil emulsions and aluminum hydroxide. Overall, we found that semi-synthetic sulfated glycolipid archaeosomes induce strong Ag-specific IgG titers and CD8 T cells to both antigens. In addition, they induce the expression of a number of cytokines/chemokines including IL-6, G-CSF, KC & MIP-2. SLA archaeosome formulations demonstrated strong adjuvant activity, superior to many of the other tested adjuvants.


Asunto(s)
Adyuvantes Inmunológicos , Éteres de Glicerilo/inmunología , Glucolípidos/inmunología , Halobacterium salinarum/química , Inmunidad Celular/efectos de los fármacos , Liposomas/inmunología , Vacunas/inmunología , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Citocinas/inmunología , Citocinas/metabolismo , Femenino , Éteres de Glicerilo/administración & dosificación , Éteres de Glicerilo/química , Glucolípidos/administración & dosificación , Glucolípidos/química , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Antígenos de Superficie de la Hepatitis B/inmunología , Inmunogenicidad Vacunal , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Liposomas/administración & dosificación , Liposomas/química , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Modelos Animales , Ovalbúmina , Pruebas Serológicas , Vacunas/administración & dosificación , Vacunas/química
8.
Int J Syst Evol Microbiol ; 68(10): 3084-3095, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30124400

RESUMEN

A mesophilic, chemolithoautotrophic, neutrophilic and aerobic ammonia-oxidizing archaeon, designated strain MY1T, was isolated from agricultural soil. Microscopic observation revealed short, rod-shaped cells with a diameter of 0.3-0.5 µm and length of 0.6-1.0 µm. The isolate had no flagella and pili, and possessed no genes associated with archaeal flagella synthesis. The major membrane lipids consisted mainly of the glycerol dibiphytanyl glycerol tetraether (GDGT) lipids GDGT-0 to GDGT-4 and crenarchaeol. The major intact polar lipids (IPLs) were determined as hexose plus phosphohexose IPL and dihexose IPL. Strain MY1T obtains energy by aerobically oxidizing ammonia and carbon by fixing CO2. An optimal growth was observed at 25 °C, at pH 7 and with 0.2-0.4 % (w/v) salinity that corresponds with its terrestrial habitat. The addition of α-keto acids was necessary to stimulate growth. The strain tolerated ammonium and nitrite concentrations up to 10 and 5 mM, respectively. The MY1T genome has a DNA G+C content of 32.7 mol%. Phylogenetic analysis based on the 16S rRNA gene showed that strain MY1T belongs to the family Nitrosopumilaceaeof the phylum Thaumarchaeota, sharing the highest 16S rRNA gene sequence similarity (96.6-97.1 %) with marine isolates of the genus Nitrosopumilus. The average nucleotide identity was 78 % between strain MY1T and Nitrosopumilus maritimus SCM1T, indicating distant relatedness. Based on the phenotypic, phylogenetic and genomic analyses, it was concluded that strain MY1T belongs to the novel genus Nitrosarchaeum, under which the name Nitrosarchaeum koreense sp. nov. is proposed as the type species. The type strain is MY1T (=JCM 31640T=KCTC 4249T).


Asunto(s)
Amoníaco/metabolismo , Archaea/clasificación , Filogenia , Microbiología del Suelo , Agricultura , Archaea/genética , Archaea/aislamiento & purificación , Composición de Base , Genes Arqueales , Éteres de Glicerilo/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Suelo/química
9.
Biophys Chem ; 238: 39-48, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29742444

RESUMEN

Liposomes have received attention as a promising class of drug delivery vehicles. To date, many approaches have been tried developing liposomes for oral use. However, no liposomal formulation is on the market so far that is approved for oral application. In this study, we investigate the miscibility of two glycerol diether bolalipids with classical saturated and unsaturated phosphatidylcholines by means of differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and dynamic light scattering (DLS). Our bolalipids contain a long C32 alkyl chain bound to glycerol in the sn-3 position and a short C16 in the sn-2 position, which further carries a racemic methyl branch. The sn-1 position of the glycerol as well as the end of the long C32 alkyl chain contain polar headgroups: either two phosphocholine headgroups (PC-Gly(2C16Me)C32-PC) or a phosphocholine and a phosphodimethylethanolamine headgroup (PC-Gly(2C16Me)C32-Me2PE). We demonstrate that glycerol diether bolalipids show better miscibility with unsaturated phosphatidylcholines than with saturated ones. Both bolalipids in mixture with the unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) form liposomes, which are stable in size upon storage. These mixed bolalipid/phospholipid vesicles could be used as an oral liposomal formulation in the future.


Asunto(s)
Éteres de Glicerilo/química , Lípidos/química , Fosfatidilcolinas/química , Estructura Molecular
10.
Macromol Biosci ; 18(1)2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28834620

RESUMEN

Treatment of retinal diseases currently demands frequent intravitreal injections due to rapid clearance of the therapeutics. The use of high molecular weight polymers can extend the residence time in the vitreous and prolong the injection intervals. This study reports a water soluble graft copolymer as a potential vehicle for sustained intravitreal drug delivery. The copolymer features a high molecular weight hyaluronic acid (HA) backbone and poly(glyceryl glycerol) (PGG) side chains attached via hydrolysable ester linkers. PGG, a polyether with 1,2-diol groups in every repeating unit available for conjugation, serves as a detachable carrier. The influence of synthesis conditions and incubation in physiological media on the molecular weight of HA is studied. The cleavage of the PGG grafts from the HA backbone is quantified and polymer-from-polymer release kinetics are determined. The biocompatibility of the materials is tested in different cell cultures.


Asunto(s)
Portadores de Fármacos/química , Ácido Hialurónico/farmacología , Polímeros/química , Enfermedades de la Retina/tratamiento farmacológico , Portadores de Fármacos/farmacología , Glicerol/química , Glicerol/farmacología , Éteres de Glicerilo/química , Éteres de Glicerilo/farmacología , Humanos , Ácido Hialurónico/química , Inyecciones Intravítreas , Cinética , Peso Molecular , Polímeros/farmacología , Enfermedades de la Retina/patología , Cuerpo Vítreo/efectos de los fármacos , Agua/química
11.
Appl Microbiol Biotechnol ; 102(1): 461-474, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29103169

RESUMEN

Archaea are widespread and abundant in aquatic and terrestrial habitats and play fundamental roles in global biogeochemical cycles. Archaeal lipids, such as isoprenoid glycerol diakyl glycerol tetraethers (iGDGTs), are important biomarkers tracing changes in archaeal community structure and biogeochemical processes in nature. However, the linkage between the archaeal populations and the GDGT distribution in the natural environment is poorly examined, which hindered the application and interpretation of GDGT-based climate or environmental proxies. We addressed this question by investigating changes in archaeal lipid composition and community structure in the context of environmental variables along the subtropical Jiulong River Watershed (JRW) and Jiulong River Estuary (JRE) in southern China. The results showed that both the archaeal cells and the polar GDGTs (P-GDGTs) in the JRW and JRE were mostly autochthonous rather than exogenous input from surrounding soils. We further found that only five (Methanobacteriales, Ca. Bathyarchaeota, Marine Benthic Groups A (MBGA), Marine Benthic Groups B (MBGB), and Marine Benthic Groups D (MBGD)) out of sixteen lineages showed significant impacts on the composition of P-GDGTs, suggesting the significant contribution of those archaea to the changes of P-GDGT compositions. Salinity and total phosphorus (TP) showed significant impact on the distribution of both genetic and P-GDGTs compositions of archaea; whereas, sand and silt contents only had significant impact on the P-GDGTs. MBGD archaea, which occur widely in marine sediments, showed positive correlations with P-TEX86 in the JRW and JRE, suggesting that uncultivated MBGD might also contribute to the variations in TEX86 signals in marine sediments. This study provided insight into the sources of P-GDGTs and the factors controlling their distributions in river-dominated continental margins, which has relevance to applications of GDGT-based proxies in paleoclimate studies.


Asunto(s)
Archaea/química , Archaea/metabolismo , Microbiología Ambiental , Éteres de Glicerilo/análisis , Lípidos/análisis , Archaea/genética , Archaea/aislamiento & purificación , China , Ecosistema , Estuarios , Sedimentos Geológicos/química , Éteres de Glicerilo/química , Lípidos/química , Ríos
12.
Int J Syst Evol Microbiol ; 67(12): 5067-5079, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29034851

RESUMEN

Four mesophilic, neutrophilic, and aerobic marine ammonia-oxidizing archaea, designated strains SCM1T, HCA1T, HCE1T and PS0T, were isolated from a tropical marine fish tank, dimly lit deep coastal waters, the lower euphotic zone of coastal waters, and near-surface sediment in the Puget Sound estuary, respectively. Cells are straight or slightly curved small rods, 0.15-0.26 µm in diameter and 0.50-1.59 µm in length. Motility was not observed, although strain PS0T possesses genes associated with archaeal flagella and chemotaxis, suggesting it may be motile under some conditions. Cell membranes consist of glycerol dibiphytanyl glycerol tetraether (GDGT) lipids, with crenarchaeol as the major component. Strain SCM1T displays a single surface layer (S-layer) with p6 symmetry, distinct from the p3-S-layer reported for the soil ammonia-oxidizing archaeon Nitrososphaera viennensis EN76T. Respiratory quinones consist of fully saturated and monounsaturated menaquinones with 6 isoprenoid units in the side chain. Cells obtain energy from ammonia oxidation and use carbon dioxide as carbon source; addition of an α-keto acid (α-ketoglutaric acid) was necessary to sustain growth of strains HCA1T, HCE1T, and PS0T. Strain PS0T uses urea as a source of ammonia for energy production and growth. All strains synthesize vitamin B1 (thiamine), B2 (riboflavin), B6 (pyridoxine), and B12 (cobalamin). Optimal growth occurs between 25 and 32 °C, between pH 6.8 and 7.3, and between 25 and 37 ‰ salinity. All strains have a low mol% G+C content of 33.0-34.2. Strains are related by 98 % or greater 16S rRNA gene sequence identity, sharing ~85 % 16S rRNA gene sequence identity with Nitrososphaera viennensis EN76T. All four isolates are well separated by phenotypic and genotypic characteristics and are here assigned to distinct species within the genus Nitrosopumilus gen. nov. Isolates SCM1T (=ATCC TSD-97T =NCIMB 15022T), HCA1T (=ATCC TSD-96T), HCE1T (=ATCC TSD-98T), and PS0T (=ATCC TSD-99T) are type strains of the species Nitrosopumilusmaritimus sp. nov., Nitrosopumilus cobalaminigenes sp. nov., Nitrosopumilus oxyclinae sp. nov., and Nitrosopumilus ureiphilus sp. nov., respectively. In addition, we propose the family Nitrosopumilaceae fam. nov. and the order Nitrosopumilales ord. nov. within the class Nitrososphaeria.


Asunto(s)
Archaea/clasificación , Sedimentos Geológicos/microbiología , Filogenia , Agua de Mar/microbiología , Amoníaco/metabolismo , Archaea/genética , Archaea/aislamiento & purificación , Composición de Base , ADN de Archaea/genética , Estuarios , Éteres de Glicerilo/química , Oxidación-Reducción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Washingtón
13.
Chemosphere ; 183: 277-285, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28551204

RESUMEN

Glycerol is currently considered a raw, renewable material, which can be used to synthesize new glycerol derivatives that may be used as green solvents. However, these compounds must be environmentally evaluated before their use. The acute ecotoxicity of a series of mono-, di-, and trialkyl ethers synthesized from glycerol for the crustacean Daphnia magna has been studied. The EC50 values of these ethers after 24 h of exposure were determined according to the OECD 202 protocol. Their possible structural-toxicity relationships according to different alkyl substituents have been discussed after applying different QSAR models (with the DARC-PELCO approach and topological parameters). The results of the immobilization test show that most of the glycerol derivatives studied exhibit relatively low ecotoxicity. There is a correlation between the lipophilicity and the increase of the toxic effect in the crustacean biomodel. Furthermore, the length and the number of the alkyl substituents and ecotoxicity are highly related.


Asunto(s)
Daphnia/efectos de los fármacos , Éteres de Glicerilo/toxicidad , Relación Estructura-Actividad Cuantitativa , Animales , Ecosistema , Éteres de Glicerilo/química , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Biológicos , Contaminantes Químicos del Agua/toxicidad
14.
Sci Rep ; 7: 44289, 2017 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-28281634

RESUMEN

This study was to develop novel soy protein isolate-based films for packaging using halloysite nanotubes (HNTs), poly-vinyl alcohol (PVA), and 1,2,3-propanetriol-diglycidyl-ether (PTGE). The structural, crystallinity, opacity, micromorphology, and thermal stability of the resultant SPI/HNTs/PVA/PTGE film were analyzed by the Attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), UV-Vis spectrophotometry, scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). The SPI/HNTs/PVA/PTGE film illustrated that HNTs were uniformly dispersed in the SPI matrix and the thermal stability of the film was enhanced. Furthermore, the tensile strength (TS) of the SPI/HNTs/PVA/PTGE film was increased by 329.3% and the elongation at the break (EB) remained unchanged. The water absorption (WA) and the moisture content (MC) were decreased by 5.1% and 10.4%, respectively, compared to the unmodified film. The results highlighted the synergistic effects of SPI, HNTs, PVA, and PTGE on the mechanical properties, water resistance, and thermal stability of SPI films, which showed excellent strength and flexibility. In short, SPI films prepared from HNTs, PVA, and PTGE showed considerable potential as packaging materials.


Asunto(s)
Éteres de Glicerilo/química , Membranas Artificiales , Nanotubos/química , Alcohol Polivinílico/química , Proteínas de Soja/química , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo , Nanotubos/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X
15.
Biochim Biophys Acta Biomembr ; 1859(5): 966-974, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28214513

RESUMEN

Archaeal tetraether membrane lipids span the whole membrane width and present two C40 isoprenoid chains bound by two glycerol groups (or one glycerol and calditol). These lipids confer stability and maintain the membrane fluidity in mesophile to extremophile environments, making them very attractive for biotechnological applications. The isoprenoid lipid composition in archaeal membranes varies with temperature, which has placed these lipids in the focus of paleo-climatological studies for over a decade. Non-hydroxylated isoprenoid archaeal lipids are typically used as paleo-thermometry proxies, but recently identified hydroxylated (OH) derivatives have also been proposed as temperature proxies. The relative abundance of hydroxylated lipids increases at lower temperatures, but the physiological function of the OH moiety remains unknown. Here we present molecular dynamics simulations of membranes formed by the acyclic glycerol-dialkyl-glycerol-tetraether caldarchaeol (GDGT-0), the most widespread archaeal core lipid, and its mono-hydroxylated variant (OH-GDGT-0) to better understand the physico-chemical properties conferred to the membrane by this additional moiety. The molecular dynamics simulations indicate that the additional OH group forms hydrogen bonds mainly with the sugar moieties of neighbouring lipids and with water molecules, effectively increasing the size of the polar headgroups. The hydroxylation also introduces local disorder that propagates along the entire alkyl chains, resulting in a slightly more fluid membrane. These changes would help to maintain trans-membrane transport in cold environments, explaining why the relative abundance of hydroxylated Archaea lipids increases at lower temperatures. The in silico approach aids to understand the underlying physiological mechanisms behind the hydroxylated lipid based paleo-thermometer recently proposed.


Asunto(s)
Éteres de Glicerilo/química , Membrana Dobles de Lípidos/química , Simulación de Dinámica Molecular , Hidroxilación , Fluidez de la Membrana , Modelos Moleculares , Temperatura
16.
Colloids Surf B Biointerfaces ; 152: 114-123, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28103528

RESUMEN

Ultradeformable archaeosomes (UDA) are nanovesicles made of total polar archaeolipids (TPA) from the archaea Halorubrum tebenquichense, soybean phosphatidylcholine and sodium cholate (3:3:1w/w). Fresh dispersions of UDA including different type of antigens are acknowledged as efficient topical vaccination agents. UDA dispersions however, if manufactured for pharmaceutical use, have to maintain colloidal stability upon liposomicidal processes such as sterilization and lyophilization (SLRUDA), needed to extend shelf life during storage. The remaining capacity of SLRUDA to act as adjuvants was therefore tested here for the first time. Another unexplored issue addressed here, is the outcome of replacing classical antigen inclusion into nanovesicles by their physical mixture. Our results showed that UDA behaved as super-stable nanovesicles because of its high endurance during heat sterilization and storage for 5 months at 40°C. The archaeolipid content of UDA however, was insufficient to protect it against lyophilization, which demanded the addition of 2.5% v/v glycerol plus 0.07% w/v glucose. No significant differences were found between serum anti-ovalbumin (OVA) IgG titers induced by fresh or SLRUDA upon topical application of 4 weekly doses at 600µg lipids/75µg OVA to Balb/c mice. Finally, SLRUDA mixed with OVA elicited the same Th2 biased plus a non-specific cell mediated response than OVA encapsulated within UDA. Concluding, we showed that TPA is key component of super-stable nanovesicles that confers resistance to heat sterilization and to storage under cold-free conditions. The finding of SLRUDA as ready-to-use topical adjuvant would lead to simpler manufacture processing and cheaper products. .


Asunto(s)
Nanopartículas/química , Vacunación , Liofilización , Éteres de Glicerilo/química , Esterilización
17.
J Asian Nat Prod Res ; 19(7): 691-696, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27756152

RESUMEN

Chemical investigation on CH2Cl2 extract of the marine sponge Leucandra sp. afforded two new compounds named leucanone A (1) and naamine J (2), together with eight known compounds (3-10). Their structures were elucidated on the basis of NMR spectroscopic analyses, and comparing with the literature. The cytotoxic activities of the compounds were evaluated against four cancer cell lines, and compound 2 showed mild cytotoxic activities against MCF-7, A549, HeLa, and PC9 cancer cell lines with IC50 values in the range of 20.1-45.3 µM.


Asunto(s)
Alcaloides/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Imidazoles/aislamiento & purificación , Lípidos/aislamiento & purificación , Poríferos/química , Alcaloides/química , Alcaloides/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Éteres de Glicerilo/química , Éteres de Glicerilo/aislamiento & purificación , Éteres de Glicerilo/farmacología , Células HeLa , Humanos , Imidazoles/química , Imidazoles/farmacología , Concentración 50 Inhibidora , Lípidos/química , Lípidos/farmacología , Células MCF-7 , Biología Marina , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
18.
Rapid Commun Mass Spectrom ; 30(1): 54-60, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26661970

RESUMEN

RATIONALE: Recent advances in analytical techniques used to study archaeal membrane lipids have led to the identification of several novel di- and tetraether lipid structures. Here, we report the presence of a previously unknown series of archaeal diethers that have been detected exclusively in hydrothermally affected environments. METHODS: Polar lipid extracts were analyzed using high-performance liquid chromatography coupled to positive ion atmospheric pressure chemical ionization mass spectrometry (HPLC/APCI-MS). Identification of the novel archaeal diethers was achieved using a triple quadrupole mass spectrometer operated in MS/MS mode and by comparison of characteristic retention time patterns. RESULTS: Modern and fossil sediments deposited under hydrothermal conditions contained variable abundances of archaeal lipids including archaeol, glycerol trialkyl glycerol tetraether (GTGT-0), isoprenoid glycerol dialkyl glycerol tetraethers (GDGTs), glycerol monoalkyl glycerol tetraethers (GMGTs) and glycerol dialkanol diethers (GDDs). In addition to these well-established archaeal lipids, we detected a novel series of archaeal diethers (i.e., glycerol monoalkanediol diethers (GMDs)) that are structurally related to GMGTs but which lack one terminal glycerol moiety and contain 0-2 cyclopentyl ring systems. CONCLUSIONS: The unique presence of GMDs in hydrothermally affected environments suggests that these compounds may constitute an exclusive and yet unknown component of the cell wall membrane of (hyper)thermophilic Archaea. The presented mass spectral characteristics will facilitate detection of these components in pure cultures of Archaea and natural environments.


Asunto(s)
Archaea/química , Glicerofosfolípidos/química , Éteres de Glicerilo/química , Lípidos de la Membrana/química , Cromatografía Líquida de Alta Presión , Fósiles , Sedimentos Geológicos/química , Glicerofosfolípidos/análisis , Éteres de Glicerilo/análisis , Respiraderos Hidrotermales/microbiología , Lípidos de la Membrana/análisis , Espectrometría de Masas en Tándem
19.
Chem Phys Lipids ; 194: 2-11, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26187854

RESUMEN

We have assessed the effect of two ether glycerol lipids, 77-6 ((2S, 3R)-4-(Tetradecyloxy)-2-amino-1,3-butanediol) and 56-5 ((S)-2-Amino-3-O-hexadecyl-1-propanol), which are substrates for sphingosine kinases, on inflammatory responses. Treatment of differentiated U937 macrophage-like cells with 77-6 but not 56-5 enhanced IL-1ß release; either alone or in the presence of LPS. The stimulatory effect of sphingosine or 77-6 on LPS-stimulated IL-1ß release was reduced by pretreatment of cells with the caspase-1 inhibitor, Ac-YVAD-CHO, thereby indicating a role for the inflammasome. The enhancement of LPS-stimulated IL-1ß release in response to sphingosine, but not 77-6, was reduced by pretreatment of cells with the cathepsin B inhibitor, CA074Me, indicating a role for lysosomal destabilization in the effect of sphingosine. Administration of 56-5 to mice increased disease progression in an experimental autoimmune encephalomyelitis model and this was associated with a considerable increase in the infiltration of CD4(+) T-cells, CD11b(+) monocytes and F4/80(+) macrophages in the spinal cord. 56-5 and 77-6 were without effect on the degradation of myc-tagged sphingosine 1-phosphate 1 receptor in CCL39 cells. Therefore, the effect of 56-5 on EAE disease progression is likely to be independent of the inflammasome or the sphingosine 1-phosphate 1 receptor. However, 56-5 is chemically similar to platelet activating factor and the exacerbation of EAE disease progression might be linked to platelet activating factor receptor signaling.


Asunto(s)
Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Éteres de Glicerilo/farmacología , Interleucina-1beta/metabolismo , Lípidos/farmacología , Animales , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Encefalomielitis Autoinmune Experimental/metabolismo , Éteres de Glicerilo/química , Células HEK293 , Humanos , Lípidos/química , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Esfingosina/farmacología , Relación Estructura-Actividad , Células Tumorales Cultivadas , Células U937
20.
Drug Deliv ; 23(7): 2497-2512, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25777339

RESUMEN

Archaeosomes as liposomes made with one or more ether lipids that are unique to the domain of Archaeobacteria, found in Archaea constitute a novel family of liposome. Achaean-type lipids consist of archaeol (diether) and/or caldarchaeol (tetraether) core structures. Archaeosomes can be produced using standard procedures (hydrated film submitted to sonication, extrusion and detergent dialysis) at any temperature in the physiological range or lower, therefore making it possible to encapsulate thermally stable compounds. Various physiological as well as environmental factors affect its stability. Archaeosomes are widely used as drug delivery systems for cancer vaccines, Chagas disease, proteins and peptides, gene delivery, antigen delivery and delivery of natural antioxidant compounds. In this review article, our major aim was to explore the applications of this new carrier system in pharmaceutical field.


Asunto(s)
Adyuvantes Inmunológicos/química , Archaea/química , Portadores de Fármacos , Sistemas de Liberación de Medicamentos/métodos , Éteres de Glicerilo/administración & dosificación , Liposomas/química , Péptidos/administración & dosificación , Péptidos/metabolismo , Estabilidad de Medicamentos , Técnicas de Transferencia de Gen , Éteres de Glicerilo/química , Éteres de Glicerilo/metabolismo , Éteres de Glicerilo/farmacología , Humanos , Péptidos/química
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