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1.
Int J Mol Sci ; 24(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894771

RESUMO

4-phenylbutyrate (PB) and structurally related compounds hold promise for treating many diseases, including cancers. However, pharmaceutical limitations, such as an unpleasant taste or poor aqueous solubility, impede their evaluation and clinical use. This study explores cyclodextrin (CD) complexation as a strategy to address these limitations. The structural chemistry of the CD complexes of these compounds was analyzed using phase solubility, nuclear magnetic resonance (NMR) spectroscopic techniques, and molecular modeling to inform the choice of CD for such application. The study revealed that PB and its shorter-chain derivative form 1:1 αCD complexes, while the longer-chain derivatives form 1:2 (guest:host) complexes. αCD includes the alkyl chain of the shorter-chain compounds, depositing the phenyl ring around its secondary rim, whereas two αCD molecules sandwich the phenyl ring in a secondary-to-secondary rim orientation for the longer-chain derivatives. ßCD includes each compound to form 1:1 complexes, with their alkyl chains bent to varying degrees within the CD cavity. γCD includes two molecules of each compound to form 2:1 complexes, with both parallel and antiparallel orientations plausible. The study found that αCD is more suitable for overcoming the pharmaceutical drawbacks of PB and its shorter-chain derivative, while ßCD is better for the longer-chain derivatives.


Assuntos
Ciclodextrinas , Ciclodextrinas/química , Química Farmacêutica/métodos , Fenilbutiratos , Preparações Farmacêuticas , Solubilidade
2.
Biol Pharm Bull ; 45(5): 576-582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35491162

RESUMO

The aim of this study was to investigate the beneficial effects of sacran, a sulfated polysaccharide, on renal damage and intestinal microflora, in 5/6 nephrectomy rats as a model for chronic kidney disease (CKD). 5/6 Nephrectomy rats were divided into sacran treated and non-treated groups and examined for lethality after 4 weeks. The 5/6 nephrectomy rats were also divided into three groups: sacran treated, non-treated and AST-120 treated groups, and treated orally in a concentration-dependent manner for 4 weeks. Renal function was estimated by biochemical and histopathological analyses. Metagenomic analysis of feces from each group after 4 weeks was also performed and changes in intestinal microflora were compared. The administration of sacran to CKD rats at ≥19 mg/d increased their survival. In addition, the sacran-treated group improved CKD-related parameters in a concentration-dependent manner, and the inhibitory effect of 40 mg/d of sacran was comparable to that of AST-120. The changes in the intestinal microflora of the sacran treated group were positively correlated with an increase in the number of Lactobacillus species, which are known to be rich in beneficial bacteria, and the increment of this beneficial bacteria was negatively correlated with the concentration of indoxyl sulfate, a uremic toxin, in plasma. These results strongly suggest that the oral administration of sacran could contribute to the stabilization of intestinal microflora in CKD rats and to the reduction of oxidative stress as well as the inhibition of progression of CKD.


Assuntos
Microbioma Gastrointestinal , Insuficiência Renal Crônica , Animais , Feminino , Humanos , Masculino , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Ratos , Insuficiência Renal Crônica/tratamento farmacológico , Sulfatos/uso terapêutico
3.
Chem Pharm Bull (Tokyo) ; 68(1): 100-102, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666462

RESUMO

Euglena gracilis EOD-1, a microalgal strain, produces large quantities of paramylon, a class of polymers known as ß-1,3-glucans and has been reported to function as a dietary fiber and to improve the metabolic syndrome including obesity. However, despite its importance, the morphometric analysis of paramylon has not been conducted so far. In this study, we attempted to observe the detailed three-dimensional structure of paramylon by focused ion beam/scanning electron microscopy (FIB/SEM). Paramylon samples were fixed and three-dimensional image reconstruction and segmentation of the image stack were created using computer software (Amira v6.0.1, FEI). The results indicated that the inside of paramylon particles (diameter: 5 µm, thickness: 3 µm) was comprised of a dense structure with no evidence of the presence of large pores and gaps, although a small 100 nm crack was observed. The specific surface area of paramylon particles measured by the Brunauer-Emmet-Teller (BET) method, was not as large as activated charcoal, but similar to those of plant starches, indicating that the cholesterol-lowering effect of paramylon cannot be simply attributed to its adsorption ability. The FIB/SEM method was found to be useful for elucidating the internal structure of small solid particles.


Assuntos
Euglena gracilis/metabolismo , Glucanos/química , Microscopia Eletrônica de Varredura , Software
4.
Chem Pharm Bull (Tokyo) ; 67(9): 915-920, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474729

RESUMO

Controlling drug crystallization is one of the important issues in pre-formulation study. In recent years, advanced approaches including the use of tailor-made additives have gathered considerable attention to control crystallization behavior of drugs. This review focuses on the use of hydrophilic cyclodextrins (CDs) as additives for controlling drug crystallization. CDs affect the crystallization of drugs in solution and in solid state based on a host-guest interaction. For example, 2,6-di-O-methyl-ß-CD and 2-hydroxybutyl-ß-CD suppressed solution-mediated transition of drugs during crystallization by the host-guest interaction; as a result, metastable forms selectively precipitated in solution. The use of CDs in crystal engineering provided an opportunity for the detection of a new polymorph by changing the crystallization pathway. It was also possible to modify crystal morphology (i.e., crystal habit) by selective suppression of crystal growth on a certain direction based on the host-gust interaction. For solid formulation, stable amorphous drug/CDs complex under humid conditions was prepared using two different CDs. An overview of some recent progress in the use of CDs in crystal engineering and in amorphous formulation is described in this review.


Assuntos
Preparações Farmacêuticas/química , beta-Ciclodextrinas/química , Acetoexamida/química , Aspirina/química , Cristalização , Composição de Medicamentos , Interações Hidrofóbicas e Hidrofílicas
5.
Chem Pharm Bull (Tokyo) ; 67(5): 493-497, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061376

RESUMO

A system for releasing a fragrance, citral (CR) over an extended period of time using three types of enteric capsules is reported. The L- and M-type capsules released CR into media with a pH above 6, while the H-type capsule released CR at a pH above 7. The pH of the releasing medium was controlled by sodium borate (SB), i.e., by adding SB-methylcellulose (MC) prepared in different weight ratios (SB-MC 1 : 2, 1 : 1 and 2 : 1) to tablets and by compressing them at different pressures. The tablet containing a large amount of SB and that was pressed at higher pressures permitted the pH of the releasing medium to be changed from 5 to 9, at 4-5 h after the addition of SB to the tablets, while negligible changes were observed for tablets containing low amounts of SB and which were compressed at lower pressures. Reflecting these pH changes, CR was released after different periods of time when SB-MC tablets and capsules containing CR were simultaneously added to the releasing medium. When enteric capsules containing CR and the pH adjusting tablets were simultaneously added to a benzyl acetate (BA) solution, BA was released at a constant rate, while CR was released for different periods of time depending on the type of capsule used. The results suggest that fragrances could be released over different time frames by using enteric capsules and pH adjusting agents, for example, the release of fragrances with sedative effects at night time and with stimulating effects in the morning.


Assuntos
Boratos/química , Preparações de Ação Retardada/química , Metilcelulose/química , Monoterpenos/administração & dosagem , Odorantes , Monoterpenos Acíclicos , Cápsulas , Composição de Medicamentos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Monoterpenos/química , Odorantes/análise
6.
Int J Mol Sci ; 20(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845767

RESUMO

Niemann-Pick disease Type C (NPC) is a rare lysosomal storage disease characterized by the dysfunction of intracellular cholesterol trafficking with progressive neurodegeneration and hepatomegaly. We evaluated the potential of 6-O-α-maltosyl-ß-cyclodextrin (G2-ß-CD) as a drug candidate against NPC. The physicochemical properties of G2-ß-CD as an injectable agent were assessed, and molecular interactions between G2-ß-CD and free cholesterol were studied by solubility analysis and two-dimensional proton nuclear magnetic resonance spectroscopy. The efficacy of G2-ß-CD against NPC was evaluated using Npc1 deficient Chinese hamster ovary (CHO) cells and Npc1 deficient mice. G2-ß-CD in aqueous solution showed relatively low viscosity and surface activity; characteristics suitable for developing injectable formulations. G2-ß-CD formed higher-order inclusion complexes with free cholesterol. G2-ß-CD attenuated dysfunction of intercellular cholesterol trafficking and lysosome volume in Npc1 deficient CHO cells in a concentration dependent manner. Weekly subcutaneous injections of G2-ß-CD (2.9 mmol/kg) ameliorated abnormal cholesterol metabolism, hepatocytomegaly, and elevated serum transaminases in Npc1 deficient mice. In addition, a single cerebroventricular injection of G2-ß-CD (21.4 µmol/kg) prevented Purkinje cell loss in the cerebellum, body weight loss, and motor dysfunction in Npc1 deficient mice. In summary, G2-ß-CD possesses characteristics favorable for injectable formulations and has therapeutic potential against in vitro and in vivo NPC models.


Assuntos
Colesterol/metabolismo , Proteína C1 de Niemann-Pick/deficiência , Doença de Niemann-Pick Tipo C/tratamento farmacológico , beta-Ciclodextrinas/administração & dosagem , Animais , Células CHO , Cricetinae , Cricetulus , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Injeções Subcutâneas , Camundongos , Doença de Niemann-Pick Tipo C/metabolismo , Ressonância Magnética Nuclear Biomolecular , Resultado do Tratamento , beta-Ciclodextrinas/farmacologia
7.
Mol Pharm ; 15(3): 1097-1104, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29411982

RESUMO

A novel glucose (Glc)-responsive gel formed by worm-like micelles (WLMs) has the potential to provide a self-regulating insulin delivery system. We have prepared a WLM gel system using 75 mM cetyltrimethylammonium bromide, 75 mM phenylboronic acid, and water. At pH 9.4, this gel-like system was highly viscous and supported its own weight, and dynamic viscoelasticity measurement indicated that it contained long and entangled WLMs. The visual observation of gels prepared to include >6 mM Glc revealed that these adopted a sol-like appearance, whereas those prepared to include a control compound (2-10 mM diethylene glycol) retained their gel-like appearance. The storage modulus ( G') of this system decreased as the Glc concentration increased (2-10 mM), indicating a gradual shortening of the WLMs. In vitro release was evaluated using a test compound (fluorescein isothiocyanate dextran) in a microsized flow system. By 120 min, the release of this compound from the WLM gel was around 27-fold greater in the presence of 100 mM Glc than without Glc or with 100 mM diethylene glycol. This demonstrated the successful preparation of a WLM gel that showed an altered drug release rate, depending on Glc concentration.


Assuntos
Glicemia/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Hipoglicemia/tratamento farmacológico , Micelas , Ácidos Borônicos/química , Cetrimônio/química , Dextranos/administração & dosagem , Dextranos/farmacocinética , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/farmacocinética , Géis/química , Humanos , Concentração de Íons de Hidrogênio , Hipoglicemia/sangue , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Viscosidade/efeitos dos fármacos , Água/química
9.
Mol Pharm ; 14(8): 2740-2748, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28661690

RESUMO

We report herein on the preparation of thermoresponsive hydrogels by taking advantage of the interaction of cyclodextrins (CDs) and a hydrophobically modified polymer. A hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC) gel formed thermoresponsive hydrogels when small amounts of α-CD were added to the solution. The HM-HPMC/α-CD showed reversible sol-gel transition in the physiological temperature range that was completely opposite to the temperature dependency shown by the original HM-HPMC. The thermoresponsive gelation was attributed to the temperature dependency of the interaction between α-CD and the hydrophobic moiety of HM-HPMC. The potency of the HM-HPMC/α-CD sol-gel transition system in ophthalmic formulation was tested on the eyes of a rabbit. The use of HM-HPMC/α-CD significantly improved the ocular absorption of a drug, diclofenac sodium, by virtue of the rapid formation of a gel on the ocular surface. That is, the HM-HPMC/α-CD was in a low viscous sol state at room temperature, which made administration easy, but it rapidly formed a viscous hydrogel on the ocular surface at physiological temperature. The thermoresponsive hydrogel based on the hydrophobically modified polymer and CD promises to have widespread applications in drug delivery.


Assuntos
Hidrogéis/química , Polímeros/química , alfa-Ciclodextrinas/química , Animais , Diclofenaco/química , Sistemas de Liberação de Medicamentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Coelhos , Temperatura
10.
Biochim Biophys Acta ; 1840(9): 2806-12, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24769178

RESUMO

BACKGROUND: Sodium octanoate (Oct) and N-acetyl-l-tryptophan (N-AcTrp) are widely used as stabilizers during pasteurization and storage of albumin products. However, exposure to light photo-degrades N-AcTrp with the formation of potentially toxic compounds. Therefore, we have examined the usefulness of N-acetyl-l-methionine (N-AcMet) in comparison with N-AcTrp for long-term stability, including photo stability, of albumin products. METHODS: Recombinant human serum albumin (rHSA) with and without additives was photo-irradiated for 4weeks. The capability of the different stabilizers to scavenge reactive oxygen species (ROS) was examined by ESR spectrometry. Carbonyl contents were assessed by a spectrophotometric method using fluoresceinamine and Western blotting, whereas the structure of rHSA was examined by SDS-PAGE, far-UV circular dichroism and differential scanning calorimetry. Binding was determined by ultrafiltration. RESULTS: N-AcMet was found to be a superior ROS scavenger both before and after photo-irradiation. The number of carbonyl groups formed was lowest in the presence of N-AcMet. According to SDS-PAGE, N-AcMet stabilizes the monomeric form of rHSA, whereas N-AcTrp induces degradation of rHSA during photo-irradiation. The decrease in α-helical content of rHSA was the smallest in the presence of Oct, without or with N-AcMet. Photo-irradiation did not affect the denaturation temperature or calorimetric enthalpy of rHSA, when N-AcMet was present. CONCLUSION: The weakly bound N-AcMet is a superior protectant of albumin, because it is a better ROS-protector and structural stabilizer than N-AcTrp, and it is probable and also useful for other protein preparations. GENERAL SIGNIFICANCE: N-AcMet is an effective stabilizer of albumin during photo-irradiation, while N-Ac-Trp promotes photo-oxidative damage to albumin.


Assuntos
Sequestradores de Radicais Livres/química , Metionina/análogos & derivados , Espécies Reativas de Oxigênio/química , Albumina Sérica/química , Triptofano/análogos & derivados , Humanos , Metionina/química , Oxirredução , Processos Fotoquímicos , Estabilidade Proteica , Triptofano/química
11.
Chem Pharm Bull (Tokyo) ; 63(5): 318-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25948325

RESUMO

The inclusion mode of Limaprost in the presence of α- and ß-cyclodextrins (CDs) was investigated to gain insight into the stabilization mechanism of Limaprost-alfadex upon the addition of ß-CD in the solid state. The inclusion sites of α- and ß-CDs were studied by NMR spectroscopic and kinetic methods. With the addition of α- and ß-CDs, displacements in (13)C chemical shifts of prostaglandin F2α (PGF2α) were observed in the ω-chain and the five-membered ring, respectively, of the drug. Similar shift changes were observed with the addition of both α- and ß-CDs. In two-dimensional (2D) (1)H-NMR spectra, intermolecular correlation peaks were observed between protons of PGF2α and protons of both α- and ß-CDs, suggesting that PGF2α interacts with α- and ß-CDs to form a ternary complex by including the ω-chain with the former CD and the five-membered ring with the latter. In kinetic studies in aqueous solution, Limaprost was degraded to 17S,20-dimethyl-trans-Δ(2)-PGA1 (11-deoxy-Δ(10)) and 17S,20-dimethyl-trans-Δ(2)-8-iso-PGE1 (8-iso). The addition of α-CD promoted the dehydration to 11-deoxy-Δ(10), while ß-CD promoted the isomerization to 8-iso, under these conditions. In the presence of both α- and ß-CDs, dehydration and isomerization were also accelerated, supporting the formation of the ternary Limaprost/α-CD/ß-CD complex.


Assuntos
Alprostadil/análogos & derivados , Água/química , alfa-Ciclodextrinas/química , beta-Ciclodextrinas/química , Alprostadil/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
12.
Int J Mol Sci ; 16(10): 24707-17, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26501272

RESUMO

In this study, we examined a possible use of a surface-deacetylated chitin nano-fiber (SDCH-NF) and hyaluronic acid (HA) interpolymer complex (IPC) tablet as a potential antioxidative compound in extended-release matrix tablets. The antioxidant properties of untreated chitin (UCH), SDCH-NF, and HA were examined using N-centered radicals derived from 1,1'-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). SDCH-NF and HA had acceptable scavenging abilities and were relatively efficient radical scavengers, but UCH was much less effective. The results suggest that SDCH-NF and HA could serve as scavengers of compounds related to the development of oxidative stress. An SDCH-NF/HA IPC tablet was prepared and evaluated as an extended-release tablet matrix using famotidine (FMT) as a model drug. The release of FMT from the IPC tablet (DCF-NF:HA=1:1) was slower than that from a SDCH-NF only tablet. Turbidity measurements and X-ray diffraction (XRD) data also indicated that the optimum complexation ratio for IPC between SDCH-NF/HA is 1/1, resulting in a good relationship between turbidity or XRD of the complex and the release ratio of FMT. These results suggest that an SDCH-NF/HA tablet has the potential for use in an extended-release IPC tablet with a high antioxidant activity.


Assuntos
Antioxidantes/química , Quitina/química , Ácido Hialurônico/química , Comprimidos/química , Difração de Raios X
13.
Chem Pharm Bull (Tokyo) ; 62(8): 786-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24859193

RESUMO

Stabilization against humidity of Limaprost (a prostaglandin E1 derivative), which is currently marketed as Opalmon, was undertaken using ß-cyclodextrin (ß-CD). Aqueous solutions of Limaprost alfadex/dextran 40 were lyophilized with and without ß-CD. Limaprost alfadex lyophilized with ß-CD was more chemically stable in humid conditions than that without ß-CD. Moreover, the addition of ß-CD as an excipient to tablets of these lyophilized composites remarkably improved the stability of Limaprost, and Limaprost in this moisture-resistant formulation was chemically stable for 19 weeks at 30°C, 75% relative humidity (R.H.). Chemical analysis of Limaprost and its degradation products indicated that degradation proceeded in the inclusion form (i.e., within the CD cavity). Solid (2)H-NMR spectroscopic studies showed that ß-CD constrained the molecular mobility of water in the solid state. These results suggested that the stabilization of Limaprost by ß-CD was at least partly due to the restricted molecular mobility of water, which acted as a catalytic species for the degradation, and also to the protection of the five-membered ring of Limaprost from water catalytic dehydration through inclusion complex formation with ß-CD.


Assuntos
Alprostadil/análogos & derivados , Excipientes/química , alfa-Ciclodextrinas/química , beta-Ciclodextrinas/química , Alprostadil/química , Dextranos/química , Estabilidade de Medicamentos , Liofilização , Umidade , Comprimidos
14.
Pharmaceutics ; 16(1)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38258093

RESUMO

Despite major improvements brought about by the introduction of taste-masked formulations of 4-phenylbutyrate (PB), poor compliance remains a significant drawback to treatment for some pediatric and dysphagic patients with urea cycle disorders (UCDs). This study reports on the development of a cyclodextrin (CD)-based orally disintegrating tablet (ODT) formulation for PB as an alternative to existing formulations. This is based on previous reports of the PB taste-masking potential of CDs and the suitability of ODTs for improving compliance in pediatric and dysphagic populations. In preliminary studies, the interactions of PB with α and ßCD in the solid state were characterized using X-ray diffraction, scanning electron microscopy, dissolution, and accelerated stability studies. Based on these studies, lyophilized PB-CD solid systems were formulated into ODTs after wet granulation. Evaluation of the ODTs showed that they had adequate physical characteristics, including hardness and friability and good storage stability. Notably, the developed αCD-based ODT for PB had a disintegration time of 28 s and achieved a slightly acidic and agreeable pH (≈5.5) in solution, which is suitable for effective PB-CD complexation and taste masking. The developed formulation could be helpful as an alternative to existing PB formulations, especially for pediatric and dysphagic UCD patients.

15.
J Pharm Pharmacol ; 75(2): 236-244, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36548517

RESUMO

OBJECTIVES: 4-Phenylbutyrate (PB), which is used in the management of urea cycle disorders, has an unpleasant taste leading to poor patient compliance. Existing PB formulations though helpful, have some limitations in their use. This study reports on attempts to mask this unpleasant taste by complexing PB with cyclodextrins (CDs) to improve patient compliance. METHODS: α, ß and γCD were used as CDs. Phase solubility studies, circular dichroism, 1H-NMR spectroscopy, including ROESY, and molecular modelling were used to investigate and characterize the PB-CD interactions in solution. The taste-masking effect of the CDs was evaluated using in vitro taste sensor measurements. KEY FINDINGS: PB interacts with α, ß and γCD in solution to form 1:1, 1:1 and 1:2 CD: PB inclusion complexes, respectively, with stability constants in the order αCD > ßCD > γCD. Taste evaluation revealed that the CDs significantly mask the taste of PB through the formation of the inclusion complexes. Notably, αCD masked the bitter taste of PB to 30% of the initial taste at a 1:1 molar ratio. CONCLUSION: αCD significantly masks the unpleasant taste of PB in solution and can be used to formulate PB to address the limitations of existing formulations and improve patient compliance and quality of life.


Assuntos
Ciclodextrinas , gama-Ciclodextrinas , Humanos , Paladar , Qualidade de Vida , Ciclodextrinas/química , Solubilidade
16.
Mol Pharm ; 8(4): 1276-84, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21591726

RESUMO

A number of papers have reported that the large cavity of γ-CyD is favorable for inclusion of C(60) and forms a 1:2 (C(60):γ-CyD) complex, whereas it is thought to be difficult for ß-CyD to form a complex at the molecular level. This is because the cavity size of ß-CyD (0.78 nm) is smaller than the van der Waals diameter of C(60) (1.0 nm). In this paper, we will report on the formation of the stable C(60) nanoparticles by the hydrophilic 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CyD) layer through weak interaction on the surface of the nanoparticles. C(60) was coground with ß-CyD, γ-CyD or HP-ß-CyD mainly in a 1:2 molar ratio by an automatic magnetic agitating mortar, the coground powders were dispersed in water, and the resulting solutions were filtered through a pore size of 0.8 µm filter. The γ-CyD and HP-ß-CyD systems gave transparent colloidal solutions consisting of C(60)/CyD nanoparticles with the size lower than 100 nm, with high yields (about 100%). The C(60)/HP-ß-CyD nanoparticles are physically stable, keeping a small size for more than 28 days, whereas the γ-CyD nanoparticles are readily aggregated to form large particles (>800 nm). Solid and liquid NMR spectroscopic studies including measurements of spin-lattice relaxation times indicated that C(60) interacted with γ-CyD and HP-ß-CyD in the solid and colloidal solutions. When compared with the γ-CyD nanoparticles, adsorption studies of a hydrophobic dye on the surface of C(60)/CyD nanoparticles indicated that the surface of the HP-ß-CyD nanoparticles is largely covered by HP-ß-CyD molecules forming hydrophilic hydration layers. The present results suggest that HP-ß-CyD is useful for the preparation of C(60) nanoparticles and medical applications such as photodynamic therapy, in spite of having a cavity size smaller than that of γ-CyD.


Assuntos
Nanopartículas/química , Nanoestruturas/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Adsorção , Coloides/química , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Modelos Químicos , Nanoestruturas/ultraestrutura
17.
Carbohydr Polym ; 256: 117419, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483011

RESUMO

Recently, antibody drugs have been used worldwide, and based on worldwide sales, 7 of the top 10 pharmaceutical products in 2019 were antibody-based drugs. However, antibody drugs often form aggregates upon thermal and shaking stresses with few efficient stabilizing agents against both stresses. Herein, we developed polypseudorotaxane (PpRX) hydrogels consisting of cyclodextrins (CyDs) and polyethylene glycol (PEG)-polypropylene glycol (PPG)-PEG block copolymers (Pluronics F108, F87, F68, and L44), and evaluated their utility as antibody stabilizing agents. α- and γ-CyDs formed PpRX hydrogels with Pluronics, where CyD/F108 gels showed remarkable stabilizing effects for human immunoglobulin G (IgG) against both thermal and shaking stresses beyond CyD/PEG gels or generic gels. The effects were probably due to the interaction between IgG and the free PPG block of Pluronic F108, resulting in the strong IgG retention in the gels. These findings suggest the great potential of CyD/Pluronic gels as pharmaceutical materials for antibody formulations.


Assuntos
Anticorpos/química , Materiais Biocompatíveis/química , Ciclodextrinas/química , Composição de Medicamentos , Excipientes/química , Hidrogéis/química , Poloxâmero/química , Química Farmacêutica/instrumentação , Preparações de Ação Retardada , Portadores de Fármacos , Humanos , Imunoglobulina G/química , Luz , Oligossacarídeos/química , Tamanho da Partícula , Polímeros/química , Rotaxanos/química , Espalhamento de Radiação , Análise Espectral Raman , Viscosidade , Difração de Raios X
18.
ACS Omega ; 6(20): 13284-13292, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34056476

RESUMO

A simple strategy for synthesizing supramolecular hybrids was developed for the preparation of bioavailable nanohybrid photosensitizers by assembling visible-light-sensitive Pt(II) meso-tetrakis(4-carboxyphenyl)porphyrinporphyrin (PtTCPP)/tomatine analogues. The hybrids were self-assembled into nanofibrous or nanosheet structures approximately 3-5 nm thick and several micrometers wide. α-Tomatine generated a unique fibrous vesicle nanostructure based on intermolecular interactions, while dehydrotomatine generated nanosheet structures. Nanoassembly of these fibrous vesicles and sheets directly affected the properties of the light-responsive photosensitizer for tumor photodynamic therapy (PDT), depending on the nanostructure of the hybrid PtTCPP/tomatine analogues. The cytotoxicity of PtTCPP to cancer cells under photoirradiation was significantly enhanced by a tomatine assembly with a fibrous vesicle nanostructure, attributable to increased incorporation of the drug into cells.

19.
Carbohydr Polym ; 253: 117246, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33279001

RESUMO

A carrier and an oral absorbent for the treatment of chronic diseases in the form of a tablet was prepared from granulated chitosan (G-CS) particles. The resulting tablet was highly dispersible and disintegrated rapidly (< 30 s) in aqueous media. The non-granulated chitosan (N-CS) powder partially crystallized (2θ = 12-15° and 20°) during wet granulation to give G-CS crystalline particles. The rate of penetration of water into G-CS aggregates was markedly faster than that for N-CS aggregates, as evidenced by the ease of disintegration of the tablets. The rapid disintegration and dispersion of the tablets in vivo was confirmed by MRI measurements after the oral administration of the both tablets to rats. Some ureic toxins were adsorbed more strongly to G-CS tablets than on N-CS tablets. The results suggest that G-CS tablets have great potential for use as a fast disintegrating carrier and as an oral adsorbent in lifestyle-related diseases.


Assuntos
Quitosana/administração & dosagem , Quitosana/química , Estilo de Vida , Desintoxicação por Sorção/métodos , Comprimidos/administração & dosagem , Comprimidos/química , Administração Oral , Adsorção , Animais , Quitosana/metabolismo , Doença Crônica/tratamento farmacológico , Cristalização , Portadores de Fármacos/química , Trato Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pós/química , Ratos , Ratos Wistar , Comprimidos/metabolismo , Temperatura , Água/química
20.
Life Sci ; 268: 118991, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33417955

RESUMO

AIMS: The objective of this study was to investigate the effects of administering sacran, a sulfated polysaccharide, on liver biology, gut microbiota, oxidative stress, and inflammation on stroke-prone spontaneously hypertensive (SHRSP5/Dmcr) rats that develop fibrotic steatohepatitis with histological similarities to that of non-alcoholic steatohepatitis (NASH). MAIN METHODS: Four groups of 8-week-old SHRSP5/Dmcr rats were fed a high fat-cholesterol (HFC) diet for 4 and 8 weeks and administered either sacran (80 mg/kg/day) or a non-treatment, respectively. Liver function was evaluated by biochemical and histopathological analyses. Hepatic inflammatory markers were measured using mRNA expression. Fecal microbial profiles were determined via 16S rRNA sequencing. A triglyceride (TG) absorption test was administered to the 8-week-old Sprague-Dawley (SD) rats. KEY FINDING: Sacran administration was observed to decrease the extent of oxidative stress and hepatic biochemical parameters in serum and hepatic injury with the levels of transforming growth factor-beta (TGF-ß1) and tumor necrosis factor-alpha (TNF-α), being increased compared to those of the non-treatment group. At the genus level, sacran administration caused a significant decrease in the harmful Prevotella genus, and a significant increase in the useful Blautia genus was observed. Sacran administration also decreased the serum TG increase that was induced by administering corn oil to the SD rats. SIGNIFICANCE: We conclude that sacran administration has the potential to reduce the absorption of lipids into blood and to improve several gut microbiotas, in the gastrointestinal tract, thereby inhibiting the subsequent development of oxidative stress and hepatic markers in the systematic circulation on NASH.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Lipídeos/farmacocinética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Polissacarídeos/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Microbioma Gastrointestinal/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Ratos Endogâmicos SHR , Ratos Sprague-Dawley
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