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José Meseguer - One of the best experts on this subject based on the ideXlab platform.
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Tumouricidal activity of gilthead seabream (Sparus aurata L.) natural cytotoxic cells: the role played in vitro and in vivo by Retinol Acetate.
Fish & shellfish immunology, 2003Co-Authors: Alberto Cuesta, María Ángeles Esteban, José MeseguerAbstract:Abstract The natural cytotoxic activity of gilthead seabream head-kidney leucocytes was evaluated after in vitro incubation with Retinol Acetate as vitamin A source, and in samples taken from specimens receiving an intraperitoneal injection or a diet supplemented with this vitamin. Isolated leucocytes were incubated with 0 to 10 −10 m all-trans-Retinol Acetate-supplemented culture medium for 0, 6 or 24 h and assayed for their tumouricidal activity which was found to increase for all the assayed concentrations and incubation times. Seabream specimens were intraperitoneally injected with 0 (control), 1·75 or 5·25 μg Retinol Acetate 100 g −1 biomass and sampled 1, 3 or 5 days post-injection. Leucocyte natural cytotoxic activity increased in a dose-dependent manner 1 and 3 days post-injection. When fish were fed a commercial diet supplemented with 0 (control), 50, 150 or 300 mg Retinol Acetate kg −1 diet for 1, 2, 4 or 6 weeks, only fish which had been fed the highest supplement for 2 weeks showed any increase in head-kidney leucocyte cytotoxic activity. Serum was isolated and analysed for all-trans-Retinol concentration by reverse-phase high-pressure-liquid-chromatography. The normal level was about 0·4 μg ml −1 serum, while treatment for 1 to 4 weeks with vitamin A increased this level. In conclusion, Retinol Acetate increases gilthead seabream head-kidney leucocyte cytotoxic activity both in vitro and in vivo .
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Changes in some innate defence parameters of seabream (Sparus aurata L.) induced by Retinol Acetate
Fish & shellfish immunology, 2002Co-Authors: Alberto Cuesta, María Ángeles Esteban, J. Ortuño, Alejandro Rodríguez, José MeseguerAbstract:The effects of high doses of dietary or intraperitoneally (i.p.) injected Retinol Acetate on the gilthead seabream (Sparus aurata L.) innate immune system were studied. Gilthead seabream specimens were fed a commercial non-supplemented diet containing 1·75 mg of vitamin A kg−1 (as control) or the same diet supplemented with 50, 150 or 300 mg of Retinol Acetate kg−1 (as vitamin A source). After 1, 2, 4 or 6 weeks, serum samples and head-kidney leucocytes were obtained from each fish. Serum lysozyme activity and myeloperoxidase (MPO) content were unaffected by the vitamin A diet content. The phagocytic and respiratory burst activities of head-kidney leucocytes were established, as well as their myeloperoxidase content. While phagocytosis was not enhanced by dietary vitamin A intake and was even slightly decreased after 2 weeks, respiratory burst activity was enhanced in specimens fed supplements of 150 and 300 mg Retinol Acetate kg−1 diet for 1 or 2 weeks. Leucocyte MPO content was also enhanced when seabream were fed the highest vitamin A dose for 2 or 4 weeks and after being fed the 150 or 50 mg supplemented diets for 4 or 6 weeks, respectively. Three different groups of seabream were i.p. injected with 1 ml of phosphate buffer containing an amount of Retinol Acetate equivalent to the daily dietary supplements from the first experiment (0-control-, 0·05 or 0·30 mg 100 g−1 biomass). Both injection doses of Retinol Acetate were toxic for the gilthead seabream which showed hypervitaminic effects. These data show that Retinol Acetate plays an important role in the gilthead seabream nonspecific cellular immune system due to its antioxidant properties. They also point to the importance of the way in which it is administered, by dietary uptake or intraperitoneal injection.
Mansoor A. Khan - One of the best experts on this subject based on the ideXlab platform.
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Response Surface Methodology for the Development of Self-Nanoemulsified Drug Delivery System (SNEDDS) of All-Trans-Retinol Acetate
Pharmaceutical Development and Technology, 2008Co-Authors: Ehab I. Taha, Ahmed Mahmoud Samy, Alaa A. Kassem, Mansoor A. KhanAbstract:The purpose was to prepare, characterize, and optimize a self-nanoemulsified drug delivery system (SNEDDS) of a model lipophilic compound, all-trans-Retinol Acetate. As part of the optimization process, the main effects, interaction effects, and quadratic effects of the formulation ingredients were investigated. Method. A three-factor, three-level Box-Behnken design was used to explore the quadratic response surfaces and construct a second-order polynomial model in the form: Y = A + A1X1+ A2X2+ A3X3+ A4X1X2+ A5X2X3+ A6X1X3+ A7X12+ A8X22+ A9X32+ E. Amount of added oil (X1), surfactant (X2), and cosurfactant (X3) were selected as the factors. Particle size (Y1), turbidity (Y2), and cumulative amount of the active ingredient emulsified after 10 (Y3) and 30 (Y4) min were the observed variables. Response surface plots were used to demonstrate the effect of factors (X1), (X2), and (X3) on the response (Y4). Amount of added soybean oil (X1), Cremophor EL (X2), and Capmul MCM-C8 (X3) showed a significant effect o...
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Response Surface Methodology for the Development of Self-Nanoemulsified Drug Delivery System (SNEDDS) of All-Trans-Retinol Acetate
Pharmaceutical development and technology, 2005Co-Authors: Ehab I. Taha, Ahmed Mahmoud Samy, Alaa A. Kassem, Mansoor A. KhanAbstract:The purpose was to prepare, characterize, and optimize a self-nanoemulsified drug delivery system (SNEDDS) of a model lipophilic compound, all-trans-Retinol Acetate. As part of the optimization process, the main effects, interaction effects, and quadratic effects of the formulation ingredients were investigated. Method. A three-factor, three-level Box-Behnken design was used to explore the quadratic response surfaces and construct a second-order polynomial model in the form: Y = A + A1X1+ A2X2+ A3X3+ A4X1X2+ A5X2X3+ A6X1X3+ A7X12+ A8X22+ A9X32+ E. Amount of added oil (X1), surfactant (X2), and cosurfactant (X3) were selected as the factors. Particle size (Y1), turbidity (Y2), and cumulative amount of the active ingredient emulsified after 10 (Y3) and 30 (Y4) min were the observed variables. Response surface plots were used to demonstrate the effect of factors (X1), (X2), and (X3) on the response (Y4). Amount of added soybean oil (X1), Cremophor EL (X2), and Capmul MCM-C8 (X3) showed a significant effect o...
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Preparation and in vitro characterization of self-nanoemulsified drug delivery system (SNEDDS) of all-trans-Retinol Acetate.
International journal of pharmaceutics, 2004Co-Authors: Ehab I. Taha, S.m. Al-saidan, Ahmed Mahmoud Samy, Mansoor A. KhanAbstract:To prepare a self-nanoemulsified drug delivery system (SNEDDS) of all-trans-Retinol Acetate, with enhanced dissolution and better chance of oral absorption. All-trans-Retinol Acetate SNEDDS was prepared using different concentrations of soybean oil (solvent) Cremophor EL (surfactant) and Capmul MCM-C8 (co-surfactant). Particle size and turbidity of the SNEDDS were determined after adding water to the oily solution. Dissolution profile of SNEDDS filled in hydroxyl propyl methyl cellulose (HPMC) capsules was determined by using water in USP apparatus 2. Ternary phase diagrams were constructed to identify the self-nanoemulsified region. The SNEDDS were evaluated by the visual observation, turbidity in nephrometric turbidity units (NTU), mean particle size (microm) and Fourier transformed-infrared spectroscopy (FT-IR). SNEDDS were thermally characterized using differential scanning calorimetry (DSC) to ensure the compatibility of the SNEDDS ingredient. From the data obtained in this work, it was clear that surfactant to co-surfactant ratio has the main impact on the physical characteristics of the emulsion formed. The optimum surfactant to co-surfactant ratio was found to be 2:1 (37.5-50% for Cremophor EL, and 18.75-25% for Capmul MCM-C8). With this ratio, the resultant nanoemulsions obtained have a particle size range of 0.103-0.051 microm, turbidity range of 18.12-2.18 NTU and t30 values (cumulative% all-trans-Retinol Acetate dissolved in 30 min) of 90.42-99.5. Also the thermograms obtained from DSC experiments showed that there is no incompatibility or interaction between the SNEDDS ingredients (soybean oil, Cremophor EL, and Capmul MCM-C8) and all-trans-Retinol Acetate. The present study revealed that the self-nanoemulsified drug delivery system of all-trans-Retinol Acetate increased its dissolution rate and has the potential to enhance its bioavailability without interaction or incompatibility between the ingredients. copyright 2004 Elsevier B.V.
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Pharmaceutical Nanotechnology Preparation and in vitro characterization of self-nanoemulsified drug delivery system (SNEDDS) of all-trans-Retinol Acetate
2004Co-Authors: Ehab I. Taha, S.m. Al-saidan, Ahmed Mahmoud Samy, Mansoor A. KhanAbstract:Purpose: To prepare a self-nanoemulsified drug delivery system (SNEDDS) of all-trans-Retinol Acetate, with enhanced dissolution and better chance of oral absorption. Method: All-trans-Retinol Acetate SNEDDS was prepared using different concentrations of soybean oil (solvent) Cremophor EL (surfactant) and Capmul MCM-C8 (co-surfactant). Particle size and turbidity of the SNEDDS were determined after adding water to the oily solution. Dissolution profile of SNEDDS filled in hydroxyl propyl methyl cellulose (HPMC) capsules was determined by using water in USP apparatus 2. Ternary phase diagrams were constructed to identify the self-nanoemulsified region. The SNEDDS were evaluated by the visual observation, turbidity in nephrometric turbidity units (NTU), mean particle size (m) and Fourier transformed-infrared spectroscopy (FT-IR). SNEDDS were thermally characterized using differential scanning calorimetry (DSC) to ensure the compatibility of the SNEDDS ingredient. Results: From the data obtained in this work, it was clear that surfactant to co-surfactant ratio has the main impact on the physical characteristics of the emulsion formed. The optimum surfactant to co-surfactant ratio was found to be 2:1 (37.5–50% for Cremophor EL, and 18.75–25% for Capmul MCM-C8). With this ratio, the resultant nanoemulsions obtained have a particle size range of 0.103–0.051m, turbidity range of 18.12–2.18 NTU and t30 values (cumulative% all-trans-Retinol Acetate dissolved in 30 min) of 90.42–99.5. Also the thermograms obtained from DSC experiments showed that there is no incompatibility or interaction between the SNEDDS ingredients (soybean oil, Cremophor EL, and Capmul MCM-C8) and all-trans-Retinol Acetate. Conclusion: The present study revealed that the self-nanoemulsified drug delivery system of all-trans-Retinol Acetate increased its dissolution rate and has the potential to enhance its bioavailability without interaction or incompatibility between the ingredients.
Alberto Cuesta - One of the best experts on this subject based on the ideXlab platform.
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Tumouricidal activity of gilthead seabream (Sparus aurata L.) natural cytotoxic cells: the role played in vitro and in vivo by Retinol Acetate.
Fish & shellfish immunology, 2003Co-Authors: Alberto Cuesta, María Ángeles Esteban, José MeseguerAbstract:Abstract The natural cytotoxic activity of gilthead seabream head-kidney leucocytes was evaluated after in vitro incubation with Retinol Acetate as vitamin A source, and in samples taken from specimens receiving an intraperitoneal injection or a diet supplemented with this vitamin. Isolated leucocytes were incubated with 0 to 10 −10 m all-trans-Retinol Acetate-supplemented culture medium for 0, 6 or 24 h and assayed for their tumouricidal activity which was found to increase for all the assayed concentrations and incubation times. Seabream specimens were intraperitoneally injected with 0 (control), 1·75 or 5·25 μg Retinol Acetate 100 g −1 biomass and sampled 1, 3 or 5 days post-injection. Leucocyte natural cytotoxic activity increased in a dose-dependent manner 1 and 3 days post-injection. When fish were fed a commercial diet supplemented with 0 (control), 50, 150 or 300 mg Retinol Acetate kg −1 diet for 1, 2, 4 or 6 weeks, only fish which had been fed the highest supplement for 2 weeks showed any increase in head-kidney leucocyte cytotoxic activity. Serum was isolated and analysed for all-trans-Retinol concentration by reverse-phase high-pressure-liquid-chromatography. The normal level was about 0·4 μg ml −1 serum, while treatment for 1 to 4 weeks with vitamin A increased this level. In conclusion, Retinol Acetate increases gilthead seabream head-kidney leucocyte cytotoxic activity both in vitro and in vivo .
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Changes in some innate defence parameters of seabream (Sparus aurata L.) induced by Retinol Acetate
Fish & shellfish immunology, 2002Co-Authors: Alberto Cuesta, María Ángeles Esteban, J. Ortuño, Alejandro Rodríguez, José MeseguerAbstract:The effects of high doses of dietary or intraperitoneally (i.p.) injected Retinol Acetate on the gilthead seabream (Sparus aurata L.) innate immune system were studied. Gilthead seabream specimens were fed a commercial non-supplemented diet containing 1·75 mg of vitamin A kg−1 (as control) or the same diet supplemented with 50, 150 or 300 mg of Retinol Acetate kg−1 (as vitamin A source). After 1, 2, 4 or 6 weeks, serum samples and head-kidney leucocytes were obtained from each fish. Serum lysozyme activity and myeloperoxidase (MPO) content were unaffected by the vitamin A diet content. The phagocytic and respiratory burst activities of head-kidney leucocytes were established, as well as their myeloperoxidase content. While phagocytosis was not enhanced by dietary vitamin A intake and was even slightly decreased after 2 weeks, respiratory burst activity was enhanced in specimens fed supplements of 150 and 300 mg Retinol Acetate kg−1 diet for 1 or 2 weeks. Leucocyte MPO content was also enhanced when seabream were fed the highest vitamin A dose for 2 or 4 weeks and after being fed the 150 or 50 mg supplemented diets for 4 or 6 weeks, respectively. Three different groups of seabream were i.p. injected with 1 ml of phosphate buffer containing an amount of Retinol Acetate equivalent to the daily dietary supplements from the first experiment (0-control-, 0·05 or 0·30 mg 100 g−1 biomass). Both injection doses of Retinol Acetate were toxic for the gilthead seabream which showed hypervitaminic effects. These data show that Retinol Acetate plays an important role in the gilthead seabream nonspecific cellular immune system due to its antioxidant properties. They also point to the importance of the way in which it is administered, by dietary uptake or intraperitoneal injection.
Lucy Sun Hwang - One of the best experts on this subject based on the ideXlab platform.
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Inhibitory effects of antioxidant vitamins against thiyl radical-induced trans fatty acid formation in PC-12 cells
Journal of Functional Foods, 2016Co-Authors: Wei Lun Hung, Bo Yang Hsu, Yen Chen Tung, Lucy Sun HwangAbstract:Abstract Alzheimer's disease (AD) is the most common form of dementia. It is characterized by aggregation of amyloid plaques and neurofibrillary tangles. The neurotoxic action of amyloid β-peptide (Aβ) involves formation of reactive oxygen species. Trans fatty acids (TFAs) are not only exogenously derived from dietary food, but also endogenously formed by free radicals. Thus, we utilized the PC-12 cell model to investigate the correlation between radical stress and endogenous formed TFAs. The results showed that thiyl radicals significantly increased TFA formation in PC-12 cells in both pre-treatment and co-treatment experiments. It was also found that Retinol Acetate significantly decreased thiyl radical-catalysed TFA formation in PC-12 cells. The anti-isomerization activity of Retinol Acetate resulted, at least in part, from its high absorption efficiency by PC-12 cells and its thiyl radical scavenging activity. Therefore, Retinol Acetate may serve as a potential antioxidant for functional foods against TFA formation during pathogenesis of AD.
A. I. Slivkin - One of the best experts on this subject based on the ideXlab platform.
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Separation and Determination of a Mixture of Fat-Soluble Vitamins A, D2, AND E and β-Carotene by Gradient Thin-Layer Chromatography
Pharmaceutical Chemistry Journal, 2016Co-Authors: O. V. Trineeva, E. F. Safonova, A. I. SlivkinAbstract:A procedure for determining and separating a mixture of fat-soluble vitamins by gradient thin-layer chromatography was developed. It was shown that a theoretical approach could be used to select the optimum thin-layer chromatographic conditions for determining tocopherol Acetate, Retinol Acetate, ergocalciferol, and β-carotene. The developed procedure was validated in terms of detection limit, specificity, efficiency, and precision. The procedure could be used for quality control of complex multivitamin preparations, medicinal plant raw material, and vegetable oils, oil extracts, and dietary supplements based on them.
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Separation and Determination of a Mixture of Fat-Soluble Vitamins A, D_2, AND E and β-Carotene by Gradient Thin-Layer Chromatography
Pharmaceutical Chemistry Journal, 2016Co-Authors: O. V. Trineeva, E. F. Safonova, A. I. SlivkinAbstract:A procedure for determining and separating a mixture of fat-soluble vitamins by gradient thin-layer chromatography was developed. It was shown that a theoretical approach could be used to select the optimum thin-layer chromatographic conditions for determining tocopherol Acetate, Retinol Acetate, ergocalciferol, and β-carotene. The developed procedure was validated in terms of detection limit, specificity, efficiency, and precision. The procedure could be used for quality control of complex multivitamin preparations, medicinal plant raw material, and vegetable oils, oil extracts, and dietary supplements based on them.
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Choice of Optimum Parameters for Vitamin a Determination in a Thin Sorbent Layer
Pharmaceutical Chemistry Journal, 2014Co-Authors: O. V. Trineeva, E. F. Safonova, A. I. SlivkinAbstract:The optimum conditions for quantitative determination of vitamin A by thin-layer chromatography (TLC) were established. It was shown that a theoretical approach could be used to choose the optimum parameters for TLC determination of Retinol Acetate.