RESUMO
We investigated the effect of the rheological properties and composition of lecithin reverse wormlike micelles (LRWs) on the skin permeation of a model of a hydrophilic drug to determine whether LRWs support uniform hydrophilic drug/oil-based formulations and good drug penetrate into skin. Here, we prepared LRWs with D (-)-ribose (RI) or glycerol (GL) as polar compounds, liquid paraffin (LP) or isopropyl myristate (IPM) as oils, and 6-carboxyfluorescein (CF) as a model for a hydrophilic drug, and evaluated the rheological properties and skin penetration characteristics of the preparations. The LRWs showed moderate viscosity at 25 °C, a typical storage temperature, but decreasing viscosity at 32 °C, the surface temperature of human skin, suggesting that the LRWs would penetrate the microstructure of skin (e.g., wrinkles and hair follicles). The highest skin permeability of CF was observed when IPM was used as the oil, suggesting that both the stratum corneum and hair follicle routes are involved in drug permeation. The penetration of CF into hair follicles is influenced not only by the rheology of the formulation but also by the interaction between IPM and sebum in the hair follicles.
Assuntos
Lecitinas , Micelas , Humanos , Lecitinas/química , Lecitinas/metabolismo , Pele/metabolismo , Absorção Cutânea , Óleos/química , ReologiaRESUMO
The objective of the study was to examine the effect of soy lecithin (SL) and cholesterol loaded cryclodestrin (CLC) on cryo-survival of sperm cryopreserved in the presence or absence of seminal plasma in Saanen dairy goats. Tris-based dilutions containing various concentrations of SL (0, 0.5%, 1.0% or 2.0%) and CLC (0, 2.0 g/L, 4.0 g/L or 6.0 g/L CLC) were used to cryopreserve Saanen dairy goat sperm. The quality of frozen-thawed sperm, including progressive motility, viability, acrosome and plasma membrane integrity, as well as fertility were detected. Results found that the optimal combination of the two cryoprotectants was 1.0% SL+4.0 g/L CLC, which significantly increased progressive motility, viability, acrosome and plasma membrane integrity of frozen thawed sperm. The impact of the two cryoprotectants in combination was not affected by the presence of seminal plasma. The conception rates obtained after artificial insemination using sperm cryopreserved with and without seminal plasma were 88.89% and 91.67% (P > 0.05), respectively. The respective values for average number of litter sizes were 1.55 ± 0.17 and 1.56 ± 0.21 (P > 0.05). Therefore, this study improved the cryopreservation efficiency of goat semen, enhanced the sperm cryosurvival, and layed a foundation for the wide application of frozen goat semen.
Assuntos
Ciclodextrinas , Preservação do Sêmen , Masculino , Animais , Ciclodextrinas/farmacologia , Lecitinas/farmacologia , Lecitinas/metabolismo , Glycine max/metabolismo , Criopreservação/métodos , Sementes , Espermatozoides , Crioprotetores/farmacologia , Crioprotetores/metabolismo , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Colesterol/farmacologia , Colesterol/metabolismo , Cabras/metabolismo , Motilidade dos EspermatozoidesRESUMO
To explore the potential benefits of dietary phospholipids (PLs) in fish glucose metabolism and to promote feed culture of Chinese perch (Siniperca chuatsi), we set up six diets to feed Chinese perch (initial mean body weight 37.01 ± 0.20 g) for 86 days, including: Control diet (CT), 1% (SL1), 2% (SL2), 3% (SL3), 4% (SL4) soybean lecithin (SL) and 2% (KO2) krill oil (KO) supplemental diets (in triplicate, 20 fish each). Our study found that the SL2 significantly improved the weight gain rate and special growth rate, but the KO2 did not. In addition, the SL2 diet significantly improved feed intake, which is consistent with the mRNA levels of appetite-related genes (npy, agrp, leptin A). Additionally, in the CT and SL-added groups, leptin A expression levels were nearly synchronized with serum glucose levels. Besides, the SL2 significantly upregulated expression levels of glut2, gk, cs, fas and downregulated g6pase in the liver, suggesting that it may enhance glucose uptake, aerobic oxidation, and conversion to fatty acids. The SL2 also maintained the hepatic crude lipid content unchanged compared to the CT, possibly by significantly down-regulating the mRNA level of hepatic lipase gene (hl), and by elevating serum low-density lipoprotein (LDL) level and intraperitoneal fat ratio in significance. Moreover, the serum high-density lipoprotein levels were significantly increased by PL supplementation, and the SL2 further significantly increased serum total cholesterol and LDL levels, suggesting that dietary PLs promote lipid absorption and transport. Furthermore, dietary SL at 1% level could enhance non-specific immune capacity, with serum total protein level being markedly higher than that in the CT group. In conclusion, it is speculated that the promotion of glucose utilization and appetite by 2% dietary SL could be linked. We suggest a 1.91% supplementation of SL in the diet for the best growth performance in juvenile Chinese perch.
Assuntos
Lecitinas , Percas , Animais , Lecitinas/farmacologia , Lecitinas/metabolismo , Glycine max , Leptina/metabolismo , Dieta/veterinária , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Glucose/farmacologia , Glucose/metabolismo , RNA Mensageiro/metabolismoRESUMO
The utility of andrographolide (AN) in visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) is limited owing to poor solubility, hindered permeation, and unstable structure under physiological conditions. The present study mainly focuses on synthesizing of andrographolide-Soya-L-α-phosphatidyl choline (ANSPC) complex in ethanol and its characterization using various spectral and analytical techniques. Results from FT-IR, 1H NMR, ROSEY, and in silico docking techniques suggest ANSPC complex formation due to inter-molecular interaction between the hydrophilic head of SPC and hydroxyl group of AN present at 24th position. ANSPC complex demonstrated the solubility of 113.93 ± 6.66 µg/mL significantly (P < 0.05) greater than 6.39 ± 0.47 µg/mL of AN. The particle size of ANSPC complex was found to be 182.2 ± 2.69 nm. The IC50 value of AN suspension (PBS, pH ~ 7.4) at 24, 48, and 72 h against Leishmania donovani (L. donovani) was noticed to be 32.76 ± 4.53, 20.87 ± 2.37, and 17.71 ± 3.06 µM/mL, respectively. Moreover, augmented aqueous solubility of ANSPC complex led to significant (P < 0.05) reduction in IC50 value, i.e., 25.02 ± 4.35, 11.31 ± 0.60, and 8.33 ± 2.71 µM/mL at 24, 48, and 72 h, respectively. The IC50 values for miltefosine were noted to be 9.84 ± 2.65, 12.13 ± 7.26, and 6.56 ± 0.61 µM/mL at similar time periods. Moreover, ANSPC complex demonstrated augmented cellular uptake at 24 h as compared to 6 h in L. donovani. We suppose that submicron size and phospholipid-mediated complexation might have endorsed the permeation of ANSPC complex across the plasma membrane of L. donovani parasite by transport mechanisms such as P-type ATPase. ANSPC complex warrants further in-depth in vivo studies under a set of stringent parameters for translating the product into a clinically viable form.
Assuntos
Leishmania donovani , Leishmaniose Visceral , Humanos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Leishmania donovani/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Lecitinas/metabolismoRESUMO
The objective of the present research was to develop fluconazole-loaded transferosomal bigels for transdermal delivery by employing statistical optimization (23 factorial design-based). Thin-film hydration was employed to prepare fluconazole-loaded transferomal suspensions, which were then incorporated into bigel system. A 23 factorial design was employed where ratios of lipids to edge activators, lipids (soya lecithin to cholesterol), and edge activators (sodium deoxycholate to Tween 80) were factors. Ex vivo permeation flux (Jss) of transferosomal bigels across porcine skin was analyzed as response. The optimal setting for optimized formulation (FO) was A= 4.96, B= 3.82, and C= 2.16. The optimized transferosomes showed 52.38 ± 1.76% DEE, 76.37 nm vesicle size, 0.233 PDI, - 20.3 mV zeta potential, and desirable deformability. TEM of optimized transferosomes exhibited a multilamelar structure. FO bigel's FE-SEM revealed a globule-shaped vesicular structure. Further, the optimized transferosomal suspension was incorporated into thyme oil (0.1% w/w)-containing bigel (TO-FO). Ex vivo transdermal fluconazole permeation from different transferosomal bigels was sustained over 24 h. The highest permeation flux (4.101 µg/cm2/h) was estimated for TO-FO bigel. TO-FO bigel presented 1.67-fold more increments of antifungal activity against Candida albicans than FO bigel. The prepared thyme oil (0.1% w/w)-containing transfersomal bigel formulations can be used as topical delivery system to treat candida related fungal infections.
Assuntos
Lipossomos , Absorção Cutânea , Lipossomos/metabolismo , Fluconazol/metabolismo , Administração Cutânea , Lecitinas/metabolismo , Sistemas de Liberação de Medicamentos , Pele/metabolismoRESUMO
CONTEXT: Gallic acid (GA) and lecithin showed important roles in antioxidant and drug delivery, respectively. A complex synthesized from GA and soybean lecithin (SL-GAC), significantly improved bioavailability of GA and pharmacological activities. However, the antioxidant activity of SL-GAC and its effect on iron-overload-induced liver injury remains unexplored. OBJECTIVE: This study investigates the antioxidant properties of SL-GAC in vitro and in mice, and its remediating effects against liver injury by iron-overloaded. MATERIALS AND METHODS: In vitro, free radical scavenging activity, lipid peroxidation inhibition, and ferric reducing power of SL-GAC were measured by absorbance photometry. In vivo, C57BL/6J mice were randomized into 4 groups: control, iron-overloaded, iron-overloaded + deferoxamine, and iron-overloaded + SL-GAC. Treatments with deferoxamine (150 mg/kg/intraperitioneally) and SL-GAC (200 mg/kg/orally) were given to the desired groups for 12 weeks, daily. Iron levels, oxidative stress, and biochemical parameters were determined by histopathological examination and molecular biological techniques. RESULTS: In vitro, SL-GAC showed DPPH and ABTS free radicals scavenging activity with IC50 values equal to 24.92 and 128.36 µg/mL, respectively. In C57BL/6J mice, SL-GAC significantly reduced the levels of serum iron (22.82%), liver iron (50.29%), aspartate transaminase (25.97%), alanine transaminase (38.07%), gamma glutamyl transferase (42.11%), malondialdehyde (19.82%), total cholesterol (45.96%), triglyceride (34.90%), ferritin light chain (18.51%) and transferrin receptor (27.39%), while up-regulated the levels of superoxide dismutase (24.69%), and glutathione (11.91%). CONCLUSIONS: These findings encourage the use of SL-GAC to treat liver injury induced by iron-overloaded. Further in vivo and in vitro studies are needed to validate its potential in clinical medicine.
Assuntos
Sobrecarga de Ferro , Hepatopatias , Camundongos , Animais , Lecitinas/metabolismo , Lecitinas/farmacologia , Lecitinas/uso terapêutico , Antioxidantes/uso terapêutico , Glycine max , Ácido Gálico/farmacologia , Desferroxamina/farmacologia , Desferroxamina/metabolismo , Desferroxamina/uso terapêutico , Camundongos Endogâmicos C57BL , Hepatopatias/tratamento farmacológico , Estresse Oxidativo , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Fígado , Ferro/metabolismo , Peroxidação de LipídeosRESUMO
Lecithin:cholesterol acyltransferase protein (LCAT) promotes the esterification reaction between cholesterol and phospholipid-derived acyl chains. Positive allosteric modulators have been developed to treat LCAT deficiencies and, plausibly, also cardiovascular diseases in the future. The mechanism of action of these compounds is poorly understood. Here computational docking and atomistic molecular dynamics simulations were utilized to study the interactions between LCAT and the activating compounds. Results indicate that all drugs bind to the allosteric binding pocket in the membrane-binding domain in a similar fashion. The presence of the compounds in the allosteric site results in a distinct spatial orientation and sampling of the membrane-binding domain (MBD). The MBD's different spatial arrangement plausibly affects the lid's movement from closed to open state and vice versa, as suggested by steered molecular dynamics simulations.
Assuntos
Lecitinas/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Regulação Alostérica , Sítios de Ligação , Colesterol/metabolismo , Esterificação , HumanosRESUMO
The actinomycete Lentzea aerocolonigenes produces the antitumor antibiotic rebeccamycin. In previous studies the rebeccamycin production was significantly increased by the addition of glass beads during cultivation in different diameters between 0.5 and 2 mm and the induced mechanical stress by the glass beads was proposed to be responsible for the increased production. Thus, this study was conducted to be a systematic investigation of different parameters for macroparticle addition, such as bead diameter, concentration, and density (glass and ceramic) as well as shaking frequency, for a better understanding of the particle-induced stress on L. aerocolonigenes. The induced stress for optimal rebeccamycin production can be estimated by a combination of stress energy and stress frequency. In addition, the macroparticle-enhanced cultivation of L. aerocolonigenes was combined with soy lecithin addition to further increase the rebeccamycin concentration. With 100 g L-1 glass beads in a diameter of 969 µm and 5 g L-1 soy lecithin a concentration of 388 mg L-1 rebeccamycin was reached after 10 days of cultivation, which corresponds to the highest rebeccamycin concentrations achieved in shake flask cultivations of L. aerocolonigenes stated in literature so far.
Assuntos
Actinobacteria/crescimento & desenvolvimento , Carbazóis/metabolismo , Vidro , Lecitinas/farmacologia , Estresse Mecânico , Lecitinas/metabolismoRESUMO
A 70-day experiment was carried out to assess the effect of different levels (0, 1 and 2%) of soy lecithin in the diet on growth, survival, antioxidant defense markers, immune gene expression and thermal tolerance limits of golden mahseer, Tor putitora fry. Percentage weight gain, specific growth rate (SGR %) and survival of mahseer fed lecithin supplemented diets were not significantly different from those of the control group. Also, the mRNA expression levels of different immune related genes such as tnfα, il-1ß, il-10, complement-3, interferon-gamma (ifnγ) and tlr4 were unaffected by dietary lecithin supplementation. Nevertheless, superoxide dismutase (SOD) activity was significantly greater in the lecithin-fed groups than the control fish. The glutathione-S-transferase (GST) activity was exceptionally high in the 2% lecithin supplemented group compared to the rest two groups. This increase in antioxidant status with dietary lecithin supplementation, however, was not reflected in the whole body malonaldehyde (MDA) levels, as it did not vary significantly among the dietary groups. Importantly, dietary inclusion of soy lecithin significantly increased upper thermal tolerance limits as evidenced by higher CTmax and LTmax values. Likewise, golden mahseer fry fed with lecithin supplemented diets (both 1 and 2%) registered significantly lower critical and lethal thermal minimum (CTmin and LTmin) values than the control group, indicating higher cold tolerance capacity. Our results thus demonstrate that the dietary inclusion of soy lecithin could enhance the upper and lower thermal tolerance limits and antioxidant status of golden mahseer fry and failed to enhance immune related gene expression.
Assuntos
Antioxidantes/metabolismo , Cyprinidae/imunologia , Imunidade Inata/genética , Lecitinas/metabolismo , Termotolerância , Ração Animal/análise , Animais , Cyprinidae/genética , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Espécies em Perigo de Extinção , Imunidade Inata/efeitos dos fármacos , Lecitinas/administração & dosagem , Distribuição Aleatória , Glycine max , Termotolerância/efeitos dos fármacosRESUMO
BACKGROUND: α-cyclodextrin (α-CD) is one of the dietary fibers that may have a beneficial effect on cholesterol and/or glucose metabolism, but its efficacy and mode of action remain unclear. METHODS: In the present study, we examined the anti-hyperglycemic effect of α-CD after oral loading of glucose and liquid meal in mice. RESULTS: Administration of 2 g/kg α-CD suppressed hyperglycemia after glucose loading, which was associated with increased glucagon-like peptide 1 (GLP-1) secretion and enhanced hepatic glucose sequestration. By contrast, 1 g/kg α-CD similarly suppressed hyperglycemia, but without increasing secretions of GLP-1 and insulin. Furthermore, oral α-CD administration disrupts lipid micelle formation through its inclusion of lecithin in the gut luminal fluid. Importantly, prior inclusion of α-CD with lecithin in vitro nullified the anti-hyperglycemic effect of α-CD in vivo, which was associated with increased intestinal mRNA expressions of SREBP2-target genes (Ldlr, Hmgcr, Pcsk9, and Srebp2). CONCLUSIONS: α-CD elicits its anti-hyperglycemic effect after glucose loading by inducing lecithin inclusion in the gut lumen and activating SREBP2, which is known to induce cholecystokinin secretion to suppress hepatic glucose production via a gut/brain/liver axis.
Assuntos
Trato Gastrointestinal/metabolismo , Hiperglicemia/prevenção & controle , Lecitinas/metabolismo , Período Pós-Prandial , Canais de Potássio Corretores do Fluxo de Internalização/fisiologia , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , alfa-Ciclodextrinas/farmacologia , Animais , Trato Gastrointestinal/efeitos dos fármacos , Hiperglicemia/etiologia , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína de Ligação a Elemento Regulador de Esterol 2/genéticaRESUMO
Brucine, one of the natural medications obtained from Nux vomica seeds, is used as an anti-inflammatory drug. Several investigations were performed to overcome its drawbacks, which will affect significantly its pharmaceutical formulation. The goal of the current investigation was to design, optimize, and evaluate the anti-inflammatory performance of BRU ethosomal gel. Brucineethosomal formulations were prepared using thin film hydration method and optimized by central composite design approach using three independent variables (lecithin concentration, cholesterol concentration, and ethanol percentage) and three response variables (vesicular size, encapsulation efficiency, and skin permeation). The optimized formulation was examined for its stability and then incorporated into HPMC gel to get BRU ethosomal gel. The obtained BRU-loaded ethosomal gel was evaluated for its physical properties, in vitro release, and ex vivo permeation and skin irritation. Finally, carrageenan-induced rat hind paw edema test was adopted for the anti-inflammatory activity. The developed BRU ethosomal gel exhibited good physical characteristics comparable with the conventional developed BRU gel. In vitro release of BRU from ethosomal gel was effectively extended for 6 h. Permeation of BRU from ethosomes was significantly higher than all formulations (p < 0.05), since it recorded steady state transdermal flux value 0.548 ± 0.03 µg/cm2 h with enhancement ratio 2.73 ± 0.23. Eventually, BRU ethosomal gel exhibited potent anti-inflammatory activity as manifested by a significant decrease in rat hind paw inflammation following 24 h. In conclusion, the study emphasized the prospective of ethosomal gel as a fortunate carrier for intensifying the anti-inflammatory effect of Brucine.
Assuntos
Absorção Cutânea , Pele , Administração Cutânea , Animais , Anti-Inflamatórios/metabolismo , Lecitinas/metabolismo , Lipossomos/metabolismo , Estudos Prospectivos , Ratos , Pele/metabolismo , Estricnina/análogos & derivadosRESUMO
A feeding experiment was conducted to evaluate the effects of dietary soybean lecithin (SBL) supplementation on performance, hemato-immunological parameters, lipid biochemistry, antioxidant status, digestive enzymes activity and intestinal histomorphometry of Caspian brown trout, Salmo trutta caspius in the pre-spawning stage. The basal diet was supplemented with 0% (control), 3%, 6%, 9% and 12% of SBL to obtain five experimental diets. Fish with an average weight of 350⯱â¯10â¯g were randomly distributed among five experimental groups and fed for 90 days. Dietary SBL resulted in better performance including specific growth rate (SGR), weight gain (WG) and feed conversion ratio (FCR) (pâ¯<â¯0.05). Among the different hemato-immunological parameters, white blood cell counts (WBC), lysozyme, alternative complement activity (ACH50) and total immunoglobulin (IgM) content of serum were significantly increased with dietary SBL inclusion (pâ¯<â¯0.05). For antioxidant enzymes, glutathione S-transferase (GST) and catalase (CAT) showed significant differences among various experimental diets (pâ¯<â¯0.05). Furthermore, digestive enzymes activity including alkaline protease, lipase and amylase were increased in those fish received SBL supplemented diets (pâ¯<â¯0.05). Our results revealed that the dietary SBL improved some physiological responses of the fish and indicate 6-9% dietary SBL supplementation would improve the physiological competence of the pre-spawning Caspian brown trout breeders.
Assuntos
Antioxidantes/metabolismo , Digestão/fisiologia , Lecitinas/metabolismo , Truta/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão/efeitos dos fármacos , Relação Dose-Resposta a Droga , Intestinos/anatomia & histologia , Intestinos/efeitos dos fármacos , Intestinos/enzimologia , Lecitinas/administração & dosagem , Distribuição Aleatória , Truta/anatomia & histologia , Truta/imunologiaRESUMO
Application of agro-industrial by-products for the production of lactic acid was studied in this paper. Brewer's spent grain (BSG), malt rootlets (MR), brewer's yeast (BY), and soy lecithin (SL) were used as raw materials in L-(+)-LA fermentation by free and immobilized Lactobacillus rhamnosus ATCC 7469. The BSG, solid remains after BSG and MR hydrolysis (BSGMRSR), and MR were evaluated as carriers for batch and repeated batch fermentations with immobilized cells. During batch fermentations with immobilized cells, high cell viability (10 to 11 log CFU/g) was achieved on all carriers. In batch fermentation with BSG as a carrier, the highest LA yield of 93.79% and volumetric productivity of 1.15 g/L/h were obtained. Furthermore, very high LA yield (95.46%), volumetric productivity (1.98 g/L/h) and L. rhamnosus viability (11.5 log CFU/g) were achieved in repeated batch fermentations with the cells immobilized on this carrier. The immobilized cells showed high survival rate (94-95%) during exposure to simulated gut condition. Based on the analysis of BSGMRSR, and BY solid remains, and on in vitro evaluation of the probiotic characteristics of immobilized cells, it was observed that they could satisfy the recommendations for high-quality feed preparation.
Assuntos
Ração Animal/análise , Fermentação , Ácido Láctico/biossíntese , Probióticos , Células Imobilizadas , Grão Comestível/metabolismo , Hidrólise , Lacticaseibacillus rhamnosus/metabolismo , Lecitinas/metabolismo , Viabilidade Microbiana , Hidrolisados de Proteína , Saccharomyces cerevisiae/metabolismoRESUMO
The aim of this study was to evaluate the quality of ram semen after cryopreservation with different levels of fennel (Foeniculum vulgare) extract (0 (F0), 5 (F5), 10 (F10) and 15 (F15) mg/L) and sperm concentrations (200 (C200) and 400 (C400)â¯×â¯106 sperm/mL) in a soy lecithin (SL)-based extender. Twenty ejaculates were collected from four ghezel rams and diluted with eight sperm concentrations/fennel combinations: F0C200, F5C200, F10C200, F15C200, F0C400, F5C400, F10C400 and F15C400. Sperm motility, abnormality, plasma membrane, viability, mitochondrial activity, lipid peroxidation (LPO), mitochondrial activity and apoptotic changes were evaluated after freeze-thawing process. It was observed that F10C400 significantly improved total and progressive motility, VSL, membrane integrity of post-thawed ram sperm. MDA level was lower in F5C200 and F10C400 compared to other treatments. The higher percentage of live sperm and the lower percentage of apoptotic sperm were obtained in F10C200 compared to F0C200, F5C200 F15C400, F0C400, F5C400 and F15C400. Extender F10C200 resulted in the highest mitochondria activity compared to the rest of the extenders except F10C400. We conclude that a combination of 10â¯mg/mL fennel (Foeniculum vulgare) extract and sperm concentration of 200â¯×â¯106 sperm/mL can improve the ram semen quality cryopreserved in a soybean lecithin based extender.
Assuntos
Crioprotetores/farmacologia , Foeniculum/química , Preparações de Plantas/farmacologia , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Animais , Membrana Celular/fisiologia , Criopreservação/métodos , Congelamento , Lecitinas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Estresse Oxidativo , Sêmen/metabolismo , Análise do Sêmen , Ovinos , Espermatozoides/metabolismoRESUMO
ApoA-I activates LCAT that converts lipoprotein cholesterol to cholesteryl ester (CE). Molecular dynamic simulations suggested earlier that helices 5 of two antiparallel apoA-I molecules on discoidal HDL form an amphipathic tunnel for migration of acyl chains and unesterified cholesterol to the active sites of LCAT. Our recent crystal structure of Δ(185-243)apoA-I showed the tunnel formed by helices 5/5, with two positively charged residues arginine 123 positioned at the edge of the hydrophobic tunnel. We hypothesized that these uniquely positioned residues Arg123 are poised for interaction with fatty acids produced by LCAT hydrolysis of the sn-2 chains of phosphatidylcholine, thus positioning the fatty acids for esterification to cholesterol. To test the importance of Arg123 for LCAT phospholipid hydrolysis and CE formation, we generated apoA-I[R123A] and apoA-I[R123E] mutants and made discoidal HDL with the mutants and WT apoA-I. Neither mutation of Arg123 changed the particle composition or size, or the protein conformation or stability. However, both mutations of Arg123 significantly reduced LCAT catalytic efficiency and the apparent Vmax for CE formation without affecting LCAT phospholipid hydrolysis. A control mutation, apoA-I[R131A], did not affect LCAT phospholipid hydrolysis or CE formation. These data suggest that Arg123 of apoA-I on discoidal HDL participates in LCAT-mediated cholesterol esterification.
Assuntos
Apolipoproteína A-I/química , Apolipoproteína A-I/metabolismo , Arginina/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferase/química , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Apolipoproteína A-I/genética , Colesterol/metabolismo , Humanos , Hidrólise , Lecitinas/metabolismo , Conformação Molecular , Fosfatidilcolina-Esterol O-Aciltransferase/genética , Fosfolipídeos/metabolismoRESUMO
The effect of the antimicrobial compound triclosan (5-chloro-2'-(2,4-dichlorophenoxy)phenol) on the permeability of lecithin liposomes and rat liver mitochondria was studied. It was found that triclosan was able to increase nonspecific permeability of liposomes in a dose-dependent manner, which was detected by the release of the fluorescent probe sulforhodamine B (SRB) from vesicles. A partial release of SRB occurs instantly at the moment of triclosan addition, which is followed by a slow leakage of the dye. The triclosan-induced release of SRB from liposomes grew as pH of the medium was decreased from 9.5 to 7.5. As revealed by the laurdan generalized polarization (GP) technique, triclosan increased laurdan GP in lecithin liposomes, indicating a decrease in membrane fluidity. Measurements of GP as a function of fluorescence excitation wavelength gave an ascending line for triclosan-containing liposomes, which can be interpreted as phase heterogeneity of the lipid/triclosan system. Dynamic light scattering experiments also showed that at a high triclosan-to-lipid molar ratio (~0.5), a population of smaller light-scattering particles (~0.4 of the size of liposomes) appear in the system. Experiments with rat liver mitochondria demonstrated that triclosan (10-70µM) induced a high-amplitude cyclosporin Ð-insensitive swelling of the organelles accompanied the release of cytochrome c. On the basis of the results obtained, possible mechanisms of the toxic effect of triclosan in eukaryotic cells are discussed.
Assuntos
Lecitinas/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Triclosan/farmacologia , Lipossomas Unilamelares/metabolismo , Animais , Anti-Infecciosos Locais/farmacologia , Citocromos c/metabolismo , Concentração de Íons de Hidrogênio , Lecitinas/química , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/ultraestrutura , Dilatação Mitocondrial/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Ratos Wistar , Rodaminas/metabolismo , Espectrometria de Fluorescência , Lipossomas Unilamelares/químicaRESUMO
This study aimed to determine the effects of supplementing the diet of adult Nile tilapia Oreochromis niloticus with phosphatidylcholine (PC) on growth performance, body composition, fatty acid composition and gene expression. Genetically Improved Farmed Tilapia fish with an initial body weight of 83·1 (sd 2·9) g were divided into six groups. Each group was hand-fed a semi-purified diet containing 1·7 (control diet), 4·0, 6·5, 11·5, 21·3 or 41·0 g PC/kg diet for 68 d. Supplemental PC improved the feed efficiency rate, which was highest in the 11·5 g PC/kg diet. Weight gain and specific growth rate were unaffected. Dietary PC increased PC content in the liver and decreased crude fat content in the liver, viscera and body. SFA and MUFA increased and PUFA decreased in muscle with increasing dietary PC. Cytoplasmic phospholipase A 2 and secreted phospholipase A 2 mRNA expression were up-regulated in the brain and heart in PC-supplemented fish. PC reduced fatty acid synthase mRNA expression in the liver and visceral tissue but increased expression in muscle. Hormone-sensitive lipase and lipoprotein lipase expression increased in the liver with increasing dietary PC. Growth hormone mRNA expression was reduced in the brain and insulin-like growth factor-1 mRNA expression in liver reduced with PC above 6·5 g/kg. Our results demonstrate that dietary supplementation with PC improves feed efficiency and reduces liver fat in adult Nile tilapia, without increasing weight gain, representing a novel dietary approach to reduce feed requirements and improve the health of Nile tilapia.
Assuntos
Ciclídeos/genética , Suplementos Nutricionais , Lecitinas/metabolismo , Fosfatidilcolinas/metabolismo , Ração Animal , Animais , Composição Corporal , Encéfalo/metabolismo , Caseínas/química , Ácido Graxo Sintases/metabolismo , Ácidos Graxos/química , Gelatina/química , Perfilação da Expressão Gênica , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Lipase Lipoproteica/metabolismo , Masculino , Músculos/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Glycine max/química , Esterol Esterase/metabolismoRESUMO
Melanoma is the deadliest type of skin cancer. CD20+ melanoma stem cells (CSCs) are pivotal for metastasis and initiation of melanoma. Therefore, selective elimination of CD20+ melanoma CSCs represents an effective treatment to eradicate melanoma. Salinomycin has emerged as an effective drug toward various CSCs. Due to its poor solubility, its therapeutic efficacy against melanoma CSCs has never been evaluated. In order to target CD20+ melanoma CSCs, we designed salinomycin-loaded lipid-polymer nanoparticles with anti-CD20 aptamers (CD20-SA-NPs). Using a single-step nanoprecipitation method, salinomycin-loaded lipid-polymer nanoparticles (SA-NPs) were prepared, then CD20-SA-NPs were obtained through conjugation of thiolated anti-CD20 aptamers to SA-NPs via a maleimide-thiol reaction. CD20-SA-NPs displayed a small size of 96.3 nm, encapsulation efficiency higher than 60% and sustained drug release ability. The uptake of CD20-SA-NPs by CD20+ melanoma CSCs was significantly higher than that of SA-NPs and salinomycin, leading to greatly enhanced cytotoxic effects in vitro, thus the IC50 values of CD20-SA-NPs were reduced to 5.7 and 2.6 µg/mL in A375 CD+20 cells and WM266-4 CD+ cells, respectively. CD20-SA-NPs showed a selective cytotoxicity toward CD20+ melanoma CSCs, as evidenced by the best therapeutic efficacy in suppressing the formation of tumor spheres and the proportion of CD20+ cells in melanoma cell lines. In mice bearing melanoma xenografts, administration of CD20-SA-NPs (salinomycin 5 mg·kg-1·d-1, iv, for 60 d) showed a superior efficacy in inhibition of melanoma growth compared with SA-NPs and salinomycin. In conclusion, CD20 is a superior target for delivering drugs to melanoma CSCs. CD20-SA-NPs display effective delivery of salinomycin to CD20+ melanoma CSCs and represent a promising treatment for melanoma.
Assuntos
Antineoplásicos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Melanoma/tratamento farmacológico , Nanopartículas/uso terapêutico , Células-Tronco Neoplásicas/efeitos dos fármacos , Piranos/uso terapêutico , Animais , Antígenos CD20/química , Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Aptâmeros de Nucleotídeos/uso terapêutico , Aptâmeros de Nucleotídeos/toxicidade , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Humanos , Lecitinas/química , Lecitinas/metabolismo , Lecitinas/uso terapêutico , Lecitinas/toxicidade , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Polietilenoglicóis/uso terapêutico , Polietilenoglicóis/toxicidade , Piranos/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Micellar liquid chromatography is a popular method used in the determination of a compound's lipophilicity. This study describes the use of the obtained micelle-water partition coefficient (log Pmw ) by such a method in the prediction of human intestinal absorption (HIA). As a result of the close resemblance of the novel composition of the micellar mobile phase to that of physiological intestinal fluid, prediction was deemed to be highly successful. The unique micellar mobile phase consisted of a mixed micellar mixture of lecithin and six bile salts, i.e. a composition matching that found in the human intestinal environment, prepared in ratios resembling those in the intestine. This is considered to be the first method to use a physiological mixture of biosurfactants in the prediction of HIA. As a result, a mathematical model with high predictive ability (R2 PRED = 81%) was obtained using multiple linear regression. The micelle-water partition coefficient (log Pmw ) obtained from micellar liquid chromatography was found to be a successful tool for prediction where the final optimum model included log Pmw and polar surface area as key descriptors with high statistical significance for the prediction of HIA. This can be attributed to the nature of the mobile phase used in this study which contains the lecithin-bile salt complex, thus forming a bilayer system and therefore mimicking absorption across the intestinal membrane.
Assuntos
Ácidos e Sais Biliares/metabolismo , Cromatografia Líquida/métodos , Absorção Intestinal/fisiologia , Micelas , Modelos Biológicos , Ácidos e Sais Biliares/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lecitinas/química , Lecitinas/metabolismo , Modelos Lineares , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: The goal of this study is to improve the transdermal delivery of phosphatidylcholine (PC) via constructing a novel nanolipid vesicular system (NLVS) with high level of permeability through the stratum corneum (SC). SIGNIFICANCE: In our study, a novel drug free NLVS was developed. The system depends on PC boundary cartilage lubrication to relieve osteoarthritic pain without developing gastrointestinal problems associated with anti-inflammatory drug. MATERIALS AND METHODS: A full two-level (23) factorial design is applied to optimize the quality of the prepared NLVS. The selected independent variables are the concentration of PC, the concentration of edge activator (EA), and EA type. The developed NLVS was evaluated for in-vitro, ex-vivo as well as in-vivo efficacy in rat animal model. RESULTS: Based on the factorial design, the selected formulation variables significantly affect the tested responses. The prepared NLV formulations have a particle size (PS)in the range of 10.34 to 496.3 nm, polydispersity index (PdI) values less than one, and negative zeta potential (ZP) range of -1.42 to -32.01 mV. In-vitro and ex-vivo study results reveal that the designed NLVS is effective in sustaining PC release and enhancing its transdermal permeation over 24 h. The optimal permeation flux through ex-vivo study is 0.415 mg/cm2/h following zero-order kinetics. Moreover, in-vivo study of the optimized formulations demonstrated remarkable reduction in inflammatory mediators associated with osteoarthritis (OA). CONCLUSION: The results indicate that the optimized drug free NLVS significantly augment transdermal delivery of PC and have a potential role in treatment of OA without the risk of systemic side effects.