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Crown- and phosphoryl-containing metal phthalocyanines in solutions of poly(N-vinylpyrrolidone): Supramolecular organization, accumulation in cells, photo-induced generation of reactive oxygen species, and cytotoxicity. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 202:111722. [DOI: 10.1016/j.jphotobiol.2019.111722] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 10/29/2019] [Accepted: 11/22/2019] [Indexed: 01/05/2023]
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2
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Morita SY, Ikeda Y, Tsuji T, Terada T. Molecular Mechanisms for Protection of Hepatocytes against Bile Salt Cytotoxicity. Chem Pharm Bull (Tokyo) 2019; 67:333-340. [DOI: 10.1248/cpb.c18-01029] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Shin-ya Morita
- Department of Pharmacy, Shiga University of Medical Science Hospital
| | - Yoshito Ikeda
- Department of Pharmacy, Shiga University of Medical Science Hospital
| | - Tokuji Tsuji
- Department of Pharmacy, Shiga University of Medical Science Hospital
| | - Tomohiro Terada
- Department of Pharmacy, Shiga University of Medical Science Hospital
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3
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Supramolecular organization of crown- and phosphoryl-containing magnesium and zinc phthalocyaninates in solutions of synthetic and natural surfactants. Russ Chem Bull 2019. [DOI: 10.1007/s11172-018-2357-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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4
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Yadav SK, Parikh K, Kumar S. Mixed micelle formation of cationic gemini surfactant with anionic bile salt: a PAH solubilization study. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.02.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Ikeda Y, Morita SY, Terada T. Cholesterol attenuates cytoprotective effects of phosphatidylcholine against bile salts. Sci Rep 2017; 7:306. [PMID: 28331225 PMCID: PMC5428433 DOI: 10.1038/s41598-017-00476-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 02/27/2017] [Indexed: 01/03/2023] Open
Abstract
Bile salts have potent detergent properties and damaging effects on cell membranes, leading to liver injury. However, the molecular mechanisms for the protection of hepatocytes against bile salts are not fully understood. In this study, we demonstrated that the cytotoxicity of nine human major bile salts to HepG2 cells and primary human hepatocytes was prevented by phosphatidylcholine (PC). In contrast, cholesterol had no direct cytotoxic effects but suppressed the cytoprotective effects of PC. PC reduced the cell-association of bile salt, which was reversed by cholesterol. Light scattering measurements and gel filtration chromatography revealed that cholesterol within bile salt/PC dispersions decreased mixed micelles but increased vesicles, bile salt simple micelles and monomers. These results suggest that cholesterol attenuates the cytoprotective effects of PC against bile salts by facilitating the formation of bile salt simple micelles and monomers. Therefore, biliary PC and cholesterol may play different roles in the pathogenesis of bile salt-induced liver injury.
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Affiliation(s)
- Yoshito Ikeda
- Department of Pharmacy, Shiga University of Medical Science Hospital, Otsu City, Shiga, 520-2192, Japan
| | - Shin-Ya Morita
- Department of Pharmacy, Shiga University of Medical Science Hospital, Otsu City, Shiga, 520-2192, Japan.
| | - Tomohiro Terada
- Department of Pharmacy, Shiga University of Medical Science Hospital, Otsu City, Shiga, 520-2192, Japan
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6
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Development of self-nanoemulsifying drug delivery system for oral bioavailability enhancement of valsartan in beagle dogs. Drug Deliv Transl Res 2016; 7:100-110. [DOI: 10.1007/s13346-016-0342-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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7
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Yang X, Lu G, Huang K, Wang R, Duan X, Yang C, Yin H, Dang Z. Synergistic solubilization of low-brominated diphenyl ether mixtures in nonionic surfactant micelles. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.07.108] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Matsuoka K, Kase A, Matsuo T, Ashida Y. Competitive Solubilization of Cholesterol/Cholesteryl Oleate and Seven Species of Sterol/Stanol in Model Intestinal Solution System. J Oleo Sci 2015; 64:783-91. [PMID: 26136176 DOI: 10.5650/jos.ess15044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The addition of plant sterols/stanols (sterols or stanols) can reduce the solubilization of cholesterol in a model intestinal solution system. We studied the molecular structure of seven different sterols/stanols and the effect they had on the solubilization of cholesterol or cholesterol ester in a model intestinal solution. The differences in the molecular structures of the sterol/stanol species influenced their abilities to reduce the solubility of cholesterol in the competitive solubilization experiments. Cholestanol whose molecular structure resembled cholesterol was the most effective at reducing the solubilization of cholesterol and cholesterol ester, with the solubilities of cholesterol and cholesteryl oleate being 41% and 39% respectively of the values observed for the single solubilizate systems. β-Sitosterol was also able to reduce the solubilities of cholesterol and cholesteryl oleate to 43% and 45% of those observed in a single solubilizate system. Both, stigmasterol and brassicasterol have an unsaturated double bond in a steroid side chain and did not exhibit major cholesterol-lowering effects. These results were reflected by the Gibbs free energy change values (ΔG(0)) for solubilization, where the sterol/stanol species with cholesterol-lowering effects had similar or larger negative ΔG(0) values than those observed for cholesterol.
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Affiliation(s)
- Keisuke Matsuoka
- Faculty of Education, Laboratory of Chemistry, Saitama University
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9
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Maswal M, Chat OA, Jabeen S, Ashraf U, Masrat R, Shah RA, Dar AA. Solubilization and co-solubilization of carbamazepine and nifedipine in mixed micellar systems: insights from surface tension, electronic absorption, fluorescence and HPLC measurements. RSC Adv 2015. [DOI: 10.1039/c4ra09870f] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We present single and simultaneous solubilization of carabamezipine and nifedipine in mixed micelles.
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Affiliation(s)
- Masrat Maswal
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Oyais Ahmad Chat
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Suraya Jabeen
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Uzma Ashraf
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Rohi Masrat
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Rais Ahmad Shah
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
| | - Aijaz Ahmad Dar
- Department of Chemistry
- University of Kashmir
- Srinagar-190 006
- India
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10
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Takeuchi E, Matsuoka K, Ishii S, Ishikawa S, Honda C, Endo K. Solubilization of polycyclic aromatic hydrocarbons in C16E7 nonionic surfactant solutions. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.09.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Mixed micelles of sodium cholate and Brij30: Their rheological behaviour and capability towards solubilization and stabilization of rifampicin. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.07.039] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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12
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Matsuoka K, Takagi K, Honda C. Micelle formation of sodium hyodeoxycholate. Chem Phys Lipids 2013; 172-173:6-13. [PMID: 23665117 DOI: 10.1016/j.chemphyslip.2013.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/10/2013] [Accepted: 04/17/2013] [Indexed: 10/26/2022]
Abstract
Sodium hyodeoxycholate (NaHDC) is the main component of hog bile salts, which play a role in the absorption of sparingly soluble materials in the intestinal solution. The biosurfactant has an amphiphilic molecular structure, similar to that of ursodeoxycholate from bear gallbladder. Micelle formation from hyodeoxycholate was studied at 308.2K using pyrene fluorescence probe to determine critical micelle concentrations (cmc) at various NaCl concentrations. The change in the fluorescence spectrum peak ratios with NaHDC concentration indicated two steps for bile salt aggregation. The first step was the formation of small micelles (cmc) at 5mM, and the second step was the formation of stable aggregates at 14 mM in aqueous solution. The aggregation of hyodeoxycholate, analyzed using the stepwise association model, was found to grow its aggregation number from 4 to 7 with increasing concentration. The aggregation number in aqueous solution was also confirmed by the static light scattering method. The average measured aggregation number of the micelles was 6.7. The micellar size was relatively small as measured by either method, but it was covered by general aggregation number of human bile salts. The degree of counterion binding to the micelles, determined using a sodium ion-selective electrode, was ca. 0.5 for the NaHDC micelles. This value was relatively high among typical bile salts. Moreover, the solubilization capacity of the NaHDC micelles was assessed using cholesterol. It became clear that NaHDC micelles hardly solubilized cholesterol compared to typical human bile salts. The maximum solubilization by NaHDC was equivalent only to that by sodium ursodeoxycholate.
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Affiliation(s)
- Keisuke Matsuoka
- Department of Physical Chemistry, Showa Pharmaceutical University, Higashi-Tamagawagakuen 3-3165, Machida, Tokyo, 194-8543, Japan.
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13
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Rahman MA, Hussain A, Hussain MS, Mirza MA, Iqbal Z. Role of excipients in successful development of self-emulsifying/microemulsifying drug delivery system (SEDDS/SMEDDS). Drug Dev Ind Pharm 2012; 39:1-19. [DOI: 10.3109/03639045.2012.660949] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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Competitive solubilization of cholesterol and β-sitosterol with changing biliary lipid compositions in model intestinal solution. Chem Phys Lipids 2012; 165:7-14. [DOI: 10.1016/j.chemphyslip.2011.10.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 10/05/2011] [Accepted: 10/11/2011] [Indexed: 11/17/2022]
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15
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Competitive solubilization of cholesterol and six species of sterol/stanol in bile salt micelles. Chem Phys Lipids 2010; 163:397-402. [PMID: 20346931 DOI: 10.1016/j.chemphyslip.2010.03.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 03/16/2010] [Accepted: 03/18/2010] [Indexed: 11/22/2022]
Abstract
Slight differences in the molecular structures of a category of sterol/stanol species affect the solubility of cholesterol in a bile salt solution. We systematically studied the preferential solubilization of cholesterol and sterol/stanol in sodium taurodeoxycholate solutions using relatively minor plant species of sterol/stanol (brassicasterol and stigmasterol) and a non-plant sterol (cholestanol). As relatively major sterol/stanol species (beta-sitosterol, beta-sitostanol, and campesterol) have already been examined using nearly identical procedures to that used in our system, we were able to sufficiently discuss the cholesterol-lowering effects resulting from the molecular structures of six sterol/stanol species. The results of competitive solubilization revealed that cholestanol has the largest cholesterol-lowering effect, decreasing cholesterol solubility to 33% of that in a single solubilizate system. The molecular structure of cholestanol is also most similar to that of cholesterol. In contrast, brassicasterol and stigmasterol have little ability to decrease cholesterol solubility in a mixed binary system. Both have an unsaturated double bond at the side chain of the steroid ring. By applying thermodynamic analyses to these results, we found that the Gibbs energy changes (DeltaG degrees ) of solubilization for sterol/stanol species with cholesterol-lowering effects show larger negative values than that for cholesterol.
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16
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Moulik SP, Mitra D. Amphiphile self-aggregation: An attempt to reconcile the agreement–disagreement between the enthalpies of micellization determined by the van’t Hoff and Calorimetry methods. J Colloid Interface Sci 2009; 337:569-78. [DOI: 10.1016/j.jcis.2009.05.064] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 05/24/2009] [Accepted: 05/27/2009] [Indexed: 10/20/2022]
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17
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Vlasova NN, Golovkova LP. Effect of bile salts on adsorption of cholesterol on silica adsorbent. COLLOID JOURNAL 2009. [DOI: 10.1134/s1061933x09040073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Efrat R, Kesselman E, Aserin A, Garti N, Danino D. Solubilization of hydrophobic guest molecules in the monoolein discontinuous QL cubic mesophase and its soft nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1316-1326. [PMID: 18781793 DOI: 10.1021/la8016084] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Hydrophobic bioactive guest molecules were solubilized in the discontinuous cubic mesophase (QL) of monoolein. Their effects on the mesophase structure and thermal behavior, and on the formation of soft nanoparticles upon dispersion of the bulk mesophase were studied. Four additives were analyzed. They were classified into two types based on their presumed location within the lipid bilayer and their influence on the phase behavior and structure. Differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), polarized light microscopy, cryogenic-transmission electron microscopy (cryo-TEM), and dynamic light scattering (DLS) were used for the analysis. We found that carbamazepine and cholesterol (type I molecules) likely localize in the hydrophobic domains, but close to the hydrophobic-hydrophilic region. They induce strong perturbation to the mesophase packing by influencing both the order of the lipid acyl chains and interactions between lipid headgroups. This results in significant reduction of the phase transition enthalpy, and phase separation into lamellar and cubic mesophases above the maximum loading capacity. The inclusion of type I molecules in the mesophase also prevents the formation of soft nanoparticles with long-range internal order upon dispersion. In their presence, only vesicles or sponge-like nanoparticles form. Phytosterols and coenzyme Q10 (type II molecules) present only moderate effects. These molecules reside in the hydrophobic domains, where they cannot alter the lipid curvature or transform the QL mesophase into another phase. Therefore, above maximum loading, excess solubilizate precipitates in crystal forms. Moreover, when type II-loaded QL is dispersed, nanoparticles with long-range order and cubic symmetry (i.e., cubosomes) do form. A model for the growth of the ordered nanoparticles was developed from a series of intermediate structures identified by cryo-TEM. It proposes the development of the internal structure by fusion events between bilayer segments.
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Affiliation(s)
- Rivka Efrat
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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19
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Solubilization of cholesterol in aqueous solution by two β-cyclodextrin dimers and a negatively charged β-cyclodextrin derivative. J INCL PHENOM MACRO 2008. [DOI: 10.1007/s10847-008-9524-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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20
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21
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Study of thermodynamic parameters for solubilization of plant sterol and stanol in bile salt micelles. Chem Phys Lipids 2008; 154:87-93. [DOI: 10.1016/j.chemphyslip.2008.05.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 05/10/2008] [Accepted: 05/13/2008] [Indexed: 11/21/2022]
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22
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Savva M, Sivakumar B, Selvi B. The Conventional Langmuir Trough Technique as a Convenient Means to Determine the Solubility of Sparingly Soluble Surface Active Molecules: Case Study Cholesterol. Colloids Surf A Physicochem Eng Asp 2008; 325:1-6. [PMID: 19609337 DOI: 10.1016/j.colsurfa.2008.04.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The feasibility of a method based on mass preservation [G. Schwarz, J. Zhang, Chem. Phys. Lipids, 110 (2001) 35-45] to determine the solubility of Cholesterol in water from monomolecular films on air/water interface was investigated. Using a mass balance equation, it was found that Cholesterol undergoes an exponential desorption at very low surface pressures followed by an almost linear desorption into the subphase at higher surface pressures until monolayer collapse. Processing of the surface pressure measurements as a function of trough area in accord with the theory, enabled the accurate determination of the molecular dimensions of Cholesterol as a function of surface pressure. Slight modification of the theory enabled accurate quantification of the surface pressure-independent apparent solubility of Cholesterol and the amount of Cholesterol desorbed into the subphase as a function of surface pressure, in the nanomolar range.
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Affiliation(s)
- Michalakis Savva
- Division of Pharmaceutical Sciences, Arnold & Marie Schwartz College of Pharmacy & Health Sciences, Long Island University, Brooklyn, NY 11201, USA
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23
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Nonappa, Maitra U. First Chemical Synthesis, Aggregation Behavior and Cholesterol Solubilization Properties of Pythocholic Acid and 16α-Hydroxycholic Acid. European J Org Chem 2007. [DOI: 10.1002/ejoc.200700211] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Zhang HM, Wang Y, Jin WJ. Study on the kinetic properties of phosphor in deoxycholate aggregates by phosphorescent quenching methodology. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 88:36-42. [PMID: 17570675 DOI: 10.1016/j.jphotobiol.2007.04.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 02/17/2007] [Accepted: 04/30/2007] [Indexed: 11/20/2022]
Abstract
Owing to the unique molecular structure and aggregate behaviors in aqueous solution, dihydroxy bile salts can provide phosphorescent probe with a special microenvironment in which the room temperature phosphorescence of probe can be detected in the presence of dissolved oxygen. It, however, is not very clear how the bile salts work in inducing this kind of oxygen-independent phosphorescence. The present work tries to offer with possible more insights by investigating the particular kinetic behaviors of 3-bromoquinoline (3-BrQ) as probe in sodium deoxycholate (NaDC) aggregate based on phosphorescent quenching methodology. The critical aggregate concentration of NaDC is estimated as about 0.5mM based on the enhancement of probe phosphorescence. As the functions of quencher Cu(2+) and NO(2)(-), the rate constants of various photophysical processes for 3-BrQ are obtained in NaDC solution and full aqueous solution, respectively. In NaDC solution, the quenching rate constant k(cu2+) equals to 1.77x10(7)M(-1)s(-1) k(no-2)(mq) 1.62x10(6)M(-1)s(-1). The exit rate k(-) and entrance rate k(+) are determined to be 16-46s(-1) and 10(6)M(-1)s(-1) levels, respectively. The quenching rate constant k(o2)(q) of dissolved oxygen is estimated as 4.15x10(4)M(-1)s(-1) in air-saturated NaDC solution at 1atm.
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Affiliation(s)
- Hong-Mei Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China
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25
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Megyesi M, Biczók L. Berberine Alkaloid as a Sensitive Fluorescent Probe for Bile Salt Aggregates. J Phys Chem B 2007; 111:5635-9. [PMID: 17474769 DOI: 10.1021/jp067702g] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Effect of sodium cholate (NaC) bile salt on the absorption and fluorescence properties of berberine cation was studied in aqueous solution and water-cosolvent mixtures. The alteration of the fluorescent behavior with increasing NaC concentration showed an entirely different trend from that found previously in the presence of sodium dodecylsulfate. Binding to bile salt agglomerates led to significant fluorescence intensity enhancement, and the fluorescence lifetime of berberine proved to be highly sensitive to the structure and size of the aggregates. The dual exponential decay kinetics above 10 mM NaC concentration showed that the probe resided in two totally different binding sites. At 2-10 mM NaC concentrations, only primary aggregates were detected. The aggregate disrupting power of cosolvents decreased in the series of dimethylformamide, acetonitrile, formamide, and methanol. These compounds enhanced the water accessibility of berberine bound to aggregates and diminished the number of secondary aggregates.
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Affiliation(s)
- Mónika Megyesi
- Chemical Research Center, Hungarian Academy of Sciences, P.O. Box 17, 1525 Budapest, Hungary
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26
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Matsuoka K, Hirosawa T, Honda C, Endo K, Moroi Y, Shibata O. Thermodynamic study on competitive solubilization of cholesterol and beta-sitosterol in bile salt micelles. Chem Phys Lipids 2007; 148:51-60. [PMID: 17524379 DOI: 10.1016/j.chemphyslip.2007.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Revised: 04/09/2007] [Accepted: 04/14/2007] [Indexed: 10/23/2022]
Abstract
Differences in the preferential solubilization of cholesterol and competitive solubilizates (beta-sitosterol and aromatic compounds) in bile salt micelles was systematically studied by changing the molar ratio of cholesterol to competitive solubilizates. The cholesterol solubility in a mixed binary system (cholesterol and beta-sitosterol) was almost half that of the cholesterol alone system, regardless of the excess beta-sitosterol quantity added. On the other hand, the mutual solubilities of cholesterol and pyrene were not inhibited by their presence in binary mixed crystals. Finally, the cholesterol solubility was measured by changing the alkyl chain length of n-alkylbenzenes. When tetradecylbenzene was added to the bile solution, the cholesterol solubility decreased slightly and was below the original cholesterol solubility. Based on Gibbs energy change (DeltaG degrees ) for solubilization, chemicals that inhibit cholesterol solubility in their combined crystal systems showed a larger negative DeltaG degrees value than cholesterol alone.
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Affiliation(s)
- Keisuke Matsuoka
- Department of Physical Chemistry, Showa Pharmaceutical University, Higashi-Tamagawagakuen 3-3165, Machida, Tokyo, Japan.
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27
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Nava P, Cecchini M, Chirico S, Gordon H, Morley S, Manor D, Atkinson J. Preparation of fluorescent tocopherols for use in protein binding and localization with the alpha-tocopherol transfer protein. Bioorg Med Chem 2006; 14:3721-36. [PMID: 16481173 DOI: 10.1016/j.bmc.2006.01.053] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 01/11/2006] [Accepted: 01/12/2006] [Indexed: 11/23/2022]
Abstract
Sixteen fluorescent analogues of the lipid-soluble antioxidant vitamin alpha-tocopherol were prepared incorporating fluorophores at the terminus of omega-functionalized 2-n-alkyl-substituted chromanols (1a-d and 4a-d) that match the methylation pattern of alpha-tocopherol, the most biologically active form of vitamin E. The fluorophores used include 9-anthroyloxy (AO), 7-nitrobenz-2-oxa-1,3-diazole (NBD), N-methyl anthranilamide (NMA), and dansyl (DAN). The compounds were designed to function as fluorescent reporter ligands for protein-binding and lipid transfer assays. The fluorophores were chosen to maximize the fluorescence changes observed upon moving from an aqueous environment (low fluorescence intensity) to an hydrophobic environment such as a protein's binding site (high fluorescence intensity). Compounds 9d (anthroyloxy) and 10d (nitrobenzoxadiazole), having a C9-carbon chain between the chromanol and the fluorophore, were shown to bind specifically and reversibly to recombinant human tocopherol transfer protein (alpha-TTP) with dissociation constants of approximately 280 and 60 nM, respectively, as compared to 25 nM for the natural ligand 2R,4'R,8'R-alpha-tocopherol. Thus, compounds have been prepared that allow the investigation of the rate of alpha-TTP-mediated inter-membrane transfer of alpha-tocopherol and to investigate the mechanism of alpha-TTP function at membranes of different composition.
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Affiliation(s)
- Phillip Nava
- Department of Chemistry and Centre for Biotechnology, Brock University, St. Catharines, Ont., Canada L2S 3A1
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28
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Sah H. Degradation patterns of tetracycline antibiotics in reverse micelles and water. Biomed Chromatogr 2006; 20:1142-9. [PMID: 16729272 DOI: 10.1002/bmc.662] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The objective of this study was to determine the chemical stability of tetracycline and oxytetracycline hydro-chlorides in reverse micelles. Their reverse micellar solutions were prepared using cetyltrimethylammonium bromide, water and ethyl formate. The aqueous solutions of the tetracycline antibiotics were also prepared for comparison. The reverse micellar and aqueous solutions were stored at 37 degrees C. Samples were analyzed by high performance liquid chromatography. When evaluation was performed on an aqueous tetracycline HCl solution, its half-life was estimated to be 329 h. Its chemical stability was not improved after being dissolved in the reverse micelles, and a similar half-life of 330 h was observed. However, there were noticeable differences between the two systems in terms of degradation kinetics and degradation byproducts. On the other hand, oxytetracycline HCl was unstable in water so that its half-life was only 34 h. Very interestingly, pronounced improvement in stability was attained with the reverse micellar system: upon dissolving in the reverse micelles, its half-life was increased to 2402 h. There were also marked differences in degradation patterns and mechanisms of oxytetracycline HCl in water and the reverse micelles. Our study indicates that the reverse micellar system has potential applications in solubilizing and stabilizing oxytetracycline HCl, thereby contributing to the development of its dosage forms.
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Affiliation(s)
- Hongkee Sah
- Department of Pharmaceutical Science, College of Pharmacy, Ewha Womans University, Daehyun-Dong, Seodaemun-Gu, Seoul 120-750, Korea.
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29
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Matsuoka K, Suzuki M, Honda C, Endo K, Moroi Y. Micellization of conjugated chenodeoxy- and ursodeoxycholates and solubilization of cholesterol into their micelles: comparison with other four conjugated bile salts species. Chem Phys Lipids 2006; 139:1-10. [PMID: 16256096 DOI: 10.1016/j.chemphyslip.2005.08.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Revised: 08/26/2005] [Accepted: 08/31/2005] [Indexed: 10/25/2022]
Abstract
Micelle formations of sodium glyco- and taurochenodeoxycholate (NaGCDC and NaTCDC) and sodium glyco- and tauroursodeoxycholates (NaGUDC and NaTUDC) was studied at 308.2 K for their critical micelle concentrations at various NaCl concentrations by pyrene fluorescence probe, and the degree of counterion binding to micelle was determined using the Corrin-Harkins plots. The degree of counterion binding was found to be 0.37-0.38 for chenodeoxycholate conjugates, while the determination of the degree was quite difficult for ursodeoxycholate conjugates. The change of I1/I3 values on the fluorescence spectrum with the conjugate bile salt concentration suggested two steps for their bile salt aggregation. The first step is a commencement of smaller aggregates, the first cmc, and the second one is a starting of stable aggregates, the second cmc. The aggregation number was determined at 308.2 K and 0.15 M NaCl concentration by static light scattering: 16.3 and 11.9 for sodium NaGCDC and NaTCDC, and 7.9 and 7.1 for NaGUDC and NaTUDC, respectively. The solubilization of cholesterol into the bile salt micelles in the presence of coexisting cholesterol phase and the maximum additive concentration (MAC) of cholesterol was determined against the bile salt concentration. The standard Gibbs energy change for the solubilization was evaluated, where the micelles were regarded as a chemical species. The solubilization was stabilized in the order of NaGUDC approximately = NaTUDC < NaTC < NaGC < NaTCDC < NaGCDC < NaTDC < NaGDC, where the preceding results were taken into the order.
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Affiliation(s)
- Keisuke Matsuoka
- Department of Physical Chemistry, Showa Pharmaceutical University, Higashi-Tamagawagakuen 3-3165, Machida, Tokyo 194-8543, Japan.
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30
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Gursoy RN, Benita S. Self-emulsifying drug delivery systems (SEDDS) for improved oral delivery of lipophilic drugs. Biomed Pharmacother 2004; 58:173-82. [PMID: 15082340 DOI: 10.1016/j.biopha.2004.02.001] [Citation(s) in RCA: 803] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Indexed: 11/24/2022] Open
Abstract
The oral delivery of hydrophobic drugs presents a major challenge because of the low aqueous solubility of such compounds. Self-emulsifying drug delivery systems (SEDDS), which are isotropic mixtures of oils, surfactants, solvents and co-solvents/surfactants, can be used for the design of formulations in order to improve the oral absorption of highly lipophilic drug compounds. SEDDS can be orally administered in soft or hard gelatin capsules and form fine relatively stable oil-in-water (o/w) emulsions upon aqueous dilution owing to the gentle agitation of the gastrointestinal fluids. The efficiency of oral absorption of the drug compound from the SEDDS depends on many formulation-related parameters, such as surfactant concentration, oil/surfactant ratio, polarity of the emulsion, droplet size and charge, all of which in essence determine the self-emulsification ability. Thus, only very specific pharmaceutical excipient combinations will lead to efficient self-emulsifying systems. Although many studies have been carried out, there are few drug products on the pharmaceutical market formulated as SEDDS confirming the difficulty of formulating hydrophobic drug compounds into such formulations. At present, there are four drug products, Sandimmune and Sandimmun Neoral (cyclosporin A), Norvir (ritonavir), and Fortovase (saquinavir) on the pharmaceutical market, the active compounds of which have been formulated into specific SEDDS. Significant improvement in the oral bioavailability of these drug compounds has been demonstrated for each case. The fact that almost 40% of the new drug compounds are hydrophobic in nature implies that studies with SEDDS will continue, and more drug compounds formulated as SEDDS will reach the pharmaceutical market in the future.
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Affiliation(s)
- R Neslihan Gursoy
- Hacettepe University, Faculty of Pharmacy, Department of Pharmaceutical Technology, 06100 Ankara, Turkey
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31
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Characteristics of conjugate bile salt–phosphatidylcholine–cholesterol–water systems. Colloids Surf B Biointerfaces 2004. [DOI: 10.1016/j.colsurfb.2003.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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32
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Mukhopadhyay S, Maitra U. Facile Synthesis, Aggregation Behavior, and Cholesterol Solubilization Ability of Avicholic Acid. Org Lett 2003; 6:31-4. [PMID: 14703343 DOI: 10.1021/ol036073f] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Avicholic acid, a major constituent of the bile of several avian species, was synthesized in eight steps from readily available chenodeoxycholic acid in 9% overall yield using Breslow's remote functionalization strategy in a key step. Micelle formation and equilibrium cholesterol solubilization properties were studied for avicholate in aqueous solution.
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Affiliation(s)
- Samrat Mukhopadhyay
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
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33
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Ninomiya R, Matsuoka K, Moroi Y. Micelle formation of sodium chenodeoxycholate and solubilization into the micelles: comparison with other unconjugated bile salts. Biochim Biophys Acta Mol Cell Biol Lipids 2003; 1634:116-25. [PMID: 14643799 DOI: 10.1016/j.bbalip.2003.09.003] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Micellization of sodium chenodeoxycholate (NaCDC) was studied for the critical micelle concentration (CMC), the micelle aggregation number, and the degree of counterion binding to micelle at 288.2, 298.2, 308.2, and 318.2 K. They were compared with those of three other unconjugated bile salts; sodium cholate (NaC), sodium deoxycholate (NaDC), and sodium ursodeoxycholate (NaUDC). The I(1)/I(3) ratio of pyrene fluorescence and the solubility dependence of solution pH were employed to determine the CMC values. As the results, a certain concentration range for the CMC and a stepwise molecular aggregation for micellization were found reasonable. Using a stepwise association model of the bile salt anions, the mean aggregation number (n) of NaCDC micelles was found to increase with the total anion concentration, while the n values decreased with increasing temperature; 9.1, 8.1, 7.4, and 6.3 at 288.2, 298.2, 308.2, and 318.2 K, respectively, at 50 mmol dm(-3). The results from four unconjugated bile salts indicate that the number, location, and orientation of hydroxyl groups in the steroid nucleus are quite important for growth of the micelles. Activity of the counterion (Na(+)) was determined by a sodium ion selective electrode in order to confirm the low counterion binding to micelles. The solubilized amount of cholesterol into the aqueous bile salt solutions increased in the order of NaUDC<NaC<NaCDC<NaDC. The first stepwise association or solubilization constants (K(1)) between a cholesterol monomer and a vacant micelle were evaluated at different bile salt concentrations. The constants were also determined for polycyclic aromatic compounds (benzene, naphthalene, anthracene, and pyrene). The corresponding DeltaG(0) value was most negative for cholesterol among the solubilizates studied, which indicated that cholesterol was thermodynamically stabilized most by solubilization into the bile salt micelles.
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Affiliation(s)
- Ryoko Ninomiya
- Chemistry and Physics of Condensed Matter, Graduate School of Sciences, Kyushu University, Ropponmatsu 4-2-1, Chuo-ku, Fukuoka 810-8560, Japan
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Matsuoka K, Maeda M, Moroi Y. Micelle formation of sodium glyco- and taurocholates and sodium glyco- and taurodeoxycholates and solubilization of cholesterol into their micelles. Colloids Surf B Biointerfaces 2003. [DOI: 10.1016/s0927-7765(03)00148-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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