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1.
Ann Gastroenterol ; 37(3): 333-340, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38779644

RESUMEN

Background: Recent advances in the treatment of inflammatory bowel disease include antitumor necrosis factor antibodies and the Janus kinase inhibitor tofacitinib, approved for ulcerative colitis. Janus kinase recruits signal transducers and activators of transcriptions (STAT), which are promising targets in inflammatory bowel diseases. However few inhibitors have been evaluated, and their selectivity with respect to STAT1 and STAT3 remains controversial. Here, we investigated the therapeutic potential of a selective inhibitor vs. a non-selective, closely related compound, in a dextran sulfate sodium (DSS) murine colitis model. Methods: Thirty Swiss/CD-1 male mice were used in this study. They were divided into a healthy control group, a colitis-DSS control group, a compound (cpd) 23-treated group, a cpd 46-treated group and an icariin-treated group. For the coadministration experiment with rutin, the cpd 46-treated group and the icariin-treated group were replaced by the oral rutin-treated group and the coadministration rutin/cpd 23-treated group. The effect of the tested inhibitors was also assessed by quantification of proinflammatory markers. Results: The selective inhibitor had a significantly greater effect than the dual inhibitor on the disease activity index. We also noticed in curative treatment a significant decrease in the most abundant proinflammatory biomarker present in neutrophilic granulocytes, myeloperoxidase and on proinflammatory cytokines, including tumor necrosis factor-α, interferon-γ, interleukins -6 and -23, with a mild synergy with rutin, the glycoside of quercetin. Conclusion: The current study shows how STAT3 selective inhibitors can exert a significant therapeutic effect in the treatment of experimental DSS-colitis.

2.
Nanoscale ; 16(11): 5715-5728, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38407269

RESUMEN

Inflammatory bowel diseases (IBDs), which include Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory diseases of the gastrointestinal tract and are characterized by chronic recurrent ulceration of the bowels. Colon-targeted drug delivery systems (DDS) have received significant attention for their potential to treat IBD by improving the inflamed tissue selectivity. Herein, antiMUC5AC-decorated drug loaded nanoparticles (NP) are suggested for active epithelial targeting and selective adhesion to the inflamed tissue in experimental colitis. NPs conjugated with antiMUC5AC (anti-MUC5) were tested for their degree of bioadhesion with HT29-MTX cells by comparison with non-targeted BSA-NP conjugates. In vivo, the selectivity of bioadhesion and the influence of ligand density in bioadhesion efficiency as well as the therapeutic benefit for glucocorticoid loaded anti-MUC5-NP were studied in a murine colitis model. Quantitative adhesion analyses showed that anti-MUC5-conjugated NP exhibited a much higher binding and selectivity to inflamed tissue compared to PNA-, IgG1- and BSA-NP conjugates used as controls. This bioadhesion efficiency was found to be dependent on the ligand density, present at the NP surface. The binding specificity between anti-MUC5 ligand and inflamed tissues was confirmed by fluorescence imaging. Both anti-MUC5-NP and all other glucocorticoid containing formulations led to a significant mitigation of the experimental colitis, as became evident from the substantial reduction of myeloperoxidase activity and pro-inflammatory cytokine concentrations (TNF-α, IL-1ß). Targeted NP by using anti-MUC5 appears to be a very promising tool in future treatment of various types of local disorders affecting the gastro-intestinal tract but not limited to colitis.


Asunto(s)
Colitis , Nanopartículas , Ratones , Animales , Glucocorticoides/uso terapéutico , Ligandos , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Nanopartículas/química , Resultado del Tratamiento , Colon/diagnóstico por imagen , Colon/metabolismo
3.
Pharmaceutics ; 15(7)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37514111

RESUMEN

A major limitation in the current topical treatment strategies for inflammatory skin disorders is the inability to selectively target the inflamed site with minimal exposure of healthy skin. Atopic dermatitis is one of the most prevalent types of dermatitis. The use of polymeric nanoparticles for targeting inflamed skin has been recently proposed, and therefore the aim of this proof-of-concept clinical study was to investigate the skin penetration and deposition of polymeric biodegradable nanoparticles in the atopic dermatitis lesions and compare the data obtained to the deposition of the particles into the healthy skin or lesion-free skin of the atopic dermatitis patients. For that, fluorescent PLGA nanoparticles in sizes of approximately 100 nm were prepared and applied to the skin of healthy volunteers and the lesional and non-lesional skin of atopic dermatitis patients. Skin biopsies were examined using confocal laser scanning microscopy to track the skin deposition and depth of penetration of the particles. Immunohistochemistry was performed to investigate the alteration in tight-junction protein distribution in the different types of skin. Results have shown that nanoparticles were found to have higher deposition into the atopic dermatitis lesions with minimal accumulation in healthy or non-lesional skin. This has been primarily correlated with the impaired barrier properties of atopic dermatitis lesions with the reduced production of Claudin-1. It was concluded that polymeric nanoparticles offer a potential tool for selective drug delivery to inflamed skin with minimal exposure risk to healthy skin.

4.
Int J Mol Sci ; 24(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37047256

RESUMEN

Skin is a major administration route for drugs, and all transdermal formulations must be tested for their capability to overcome the cutaneous barrier. Therefore, developing highly reliable skin models is crucial for preclinical studies. The current in vitro models are unable to replicate the living skin in all its complexity; thus, to date, excised human skin is considered the gold standard for in vitro permeation studies. However, skin explants have a limited life span. In an attempt to overcome this problem, we used an innovative bioreactor that allowed us to achieve good structural and functional preservation in vitro of explanted human skin for up to 72 h. This device was then used to set up an in vitro inflammatory model by applying two distinct agents mimicking either exogenous or endogenous stimuli: i.e., dithranol, inducing the contact dermatitis phenotype, and the substance P, mimicking neurogenic inflammation. Our in vitro system proved to reproduce inflammatory events observed in vivo, such as vasodilation, increased number of macrophages and mast cells, and increased cytokine secretion. This bioreactor-based system may therefore be suitably and reliably used to simulate in vitro human skin inflammation and may be foreseen as a promising tool to test the efficacy of drugs and cosmetics.


Asunto(s)
Hidrodinámica , Piel , Humanos , Piel/metabolismo , Administración Cutánea , Absorción Cutánea , Inflamación/metabolismo , Preparaciones Farmacéuticas/metabolismo
5.
Materials (Basel) ; 16(3)2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36770166

RESUMEN

Lipoproteins are natural nanostructures responsible for the transport of cholesterol and other lipids in the blood. They are characterized by having a lipophilic core surrounded by an amphiphilic shell composed of phospholipids, cholesterol and one or more apolipoproteins. Being endogenous carriers makes them suitable for drug delivery purposes. Here, we investigate the effect of lipoproteins' intricate composition on the entrapment efficiency of a model drug "Cyclosporine A" into the different types of lipoproteins, namely, HDL, LDL and VLDL. It was observed that the protein content of the lipoproteins had the highest effect on the entrapment of the drug with a correlation coefficient of 0.80, 0.81 and 0.96 for HDL, LDL and VLDL respectively. This was even confirmed by the effect of plasma on the association rate of lipoproteins and the drug. The second effective factor is the cholesterol concentration, while triglycerides and phospholipids had a negligible effect.

6.
Acta Ophthalmol ; 101(1): e61-e68, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35920328

RESUMEN

PURPOSE: The aim of this study was to evaluate docosahexaenoic acid (DHA) as a potential antifibrotic agent after glaucoma filtration surgery (GFS) in rats. METHODS: A total of 36 10-week-old Brown Norway rats underwent GFS. Animals were equally divided into three groups: a control group, a DHA group and a mitomycin C (MMC) group. Intraocular pressure (IOP) was measured using a dynamic rebound tonometer, and a photograph of the surgical site was taken on days 1, 3, 7, 10, 14 and 17. The incorporation of DHA into fibroblasts was evaluated by gas chromatography. The expression of alfa-smooth muscle actin (α-SMA) and Smad proteins was assessed by Western blotting. RESULTS: IOP decreased after surgery in animals from the three groups on day 1 after surgery. Over time, IOP remained lower in the DHA and MMC groups than in the control group (median [interquartile range] 8.0 [7.0-8.0] and 8.0 [7.3-8.0] mmHg vs. 9.0 [8.0-9.0] mmHg, respectively; p < 0.001). Bleb area in the DHA and MMC groups remained larger than that of the control group from day 7 to day 14 (3.9 [2.9-5.2] and 3.5 [2.3-4.4] mm2 vs. 2.3 [2.0-2.8] mm2 , respectively; p = 0.0021). We did not observe any change in DHA concentrations in the fibroblasts of the DHA group compared with the other groups. CONCLUSION: The impact of DHA on IOP and bleb area was similar to that of MMC. The mechanisms of action of DHA in rat eye fibroblasts deserve further investigation.


Asunto(s)
Cirugía Filtrante , Glaucoma , Trabeculectomía , Animales , Ratas , Modelos Animales de Enfermedad , Ácidos Docosahexaenoicos , Fibrosis , Glaucoma/cirugía , Presión Intraocular , Mitomicina/farmacología
7.
Int J Pharm ; 627: 122235, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36170899

RESUMEN

Spray-freeze-drying (SFD) processes are usually using aqueous solvent systems, which however, exclude the use of SFD for poorly water-soluble drugs/excipients. Here, we evaluated dimethyl sulfoxide for its suitability in formulating SFD particles (lyospheres®). Rivaroxaban was spray-freeze-dried from DMSO solutions containing polyvinyl pyrrolidone (PVP; Kollidon® 25), vinylpyrrolidone-vinyl acetate copolymer (PVP-VA; Kollidon® VA64) or polyvinyl alcohol 4-88 (PVA) forming porous lyospheres® (median particle size 250 to 350 µm). Rivaroxaban was amorphous with all three polymers, which in combination with the high porosity resulted in rapid dissolution in vitro within 10 min. Consequently, this translated in lower Tmax (0.5-1.0 h) after oral administration of lyospheres® to rats (compared with Tmax of 4 h with coarse rivaroxaban). Lyosphere formulations achieved a distinct bioavailability increase (AUC(0-inf) = 1487 ± 657 ng*h/ml with PVP; 4426 ± 1553 ng*h/ml with PVP-VA; 9569 ± 3868 ng*h/ml with PVA lyospheres®; whereas 385 ± 145 ng*h/ml with coarse rivaroxaban). These in vitro and in vivo results underlined the benefit of using DMSO in SFD that can broaden the applicability of the SFD process to a much larger repertoire of poorly water-soluble drugs/excipients.


Asunto(s)
Dimetilsulfóxido , Excipientes , Ratas , Animales , Rivaroxabán , Solubilidad , Povidona , Alcohol Polivinílico , Polivinilos , Liofilización/métodos , Tamaño de la Partícula , Solventes , Agua
8.
Nanotoxicology ; 16(2): 165-182, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35579945

RESUMEN

The E551 food additive is composed of synthetic amorphous silica particles. The current regulation does not mention any specifications regarding their size and granulometric distribution, thus allowing the presence of silica nanoparticles despite their potential toxicity. The digestion process could modify their physicochemical properties and then influence their toxicological profile. After physicochemical characterization, subacute toxicity of engineered silica nanoparticles from 20 to 200 nm, native and digested E551 additives were evaluated from in vitro models of the intestinal barrier. Single cultures and a co-culture of enterocytes and mucus-secreting cells were established to investigate the mucus role. Toxicological endpoints including cytotoxicity, ROS production, intestinal permeability increase, and actin filament disruption were addressed after a 7-day exposure. The results showed a size-dependent effect of silica nanoparticles on cytotoxicity and intestinal permeability. A time-dependent disruption of actin filaments was observed in Caco-2 cells. The mucus layer spread on the HT29-MTX single culture acted as an efficient protective barrier while in the co-culture, small nanoparticles were able to cross it to reach the cells. From a hydrodynamic diameter of 70 nm, nanoparticles were not internalized in the intestinal cells, even in mucus-free models. Digestion did not affect the physicochemical properties of the additive. Due to a mean hydrodynamic diameter close to 200 nm, both native and digested E551 additives did not induce any toxic effect in intestinal barrier models. This study emphasized a cutoff size of 70 nm from which the interactions of the E551 additive with intestinal cells would be limited.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Células CACO-2 , Técnicas de Cocultivo , Aditivos Alimentarios/química , Aditivos Alimentarios/toxicidad , Células HT29 , Humanos , Mucosa Intestinal , Moco , Nanopartículas/química , Nanopartículas/toxicidad , Dióxido de Silicio/química , Dióxido de Silicio/toxicidad
9.
Eur J Pharm Biopharm ; 174: 20-28, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35339657

RESUMEN

Poorly water-soluble drugs are still a major challenge to overcome in order to achieve sufficiently high oral bioavailability. Spray freeze drying (SFD) is proposed here as an alternative for the preparation of amorphous, free-flowing porous celecoxib spheres for enhanced drug dissolution. Tertiary butyl alcohol solutions of celecoxib + excipient (povidone, hydroxypropyl methylcellulose acetate succinate (HPMC-AS) and Soluplus®) at variable ratios were sprayed into a cooled spray tower, followed by vacuum freeze drying. Final porous particles were free-flowing, highly spherical (circularity ≥ 0.96) and mean diameters ranging from 210 to 800 µm, depending on excipient and drug content. XRPD measurements showed that Celecoxib was amorphous in all formulations and remained stable during 6 months storage. Kollidon 25 and HPMC-AS combinations resulted in the highest dissolution rates as well as dissolved drug amounts (30.4 ± 1.5 µg/ml and 41.8 ± 1.7 µg/ml) which in turn was 2-fold and 1.3-fold increase compared to film casted amorphous reference formulations, respectively. This phenomenon also translated into a faster onset of the drug absorption in-vivo, with significantly lower tmax values, while AUC values were non-significantly lowered compared to amorphous references. The high porosity of SFDs led to the advantageous accelerated dissolution which also translated into faster onset of absorption in-vivo.


Asunto(s)
Excipientes , Povidona , Celecoxib , Liofilización , Porosidad , Solubilidad
10.
Pharmaceutics ; 14(2)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35214083

RESUMEN

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract with increasing incidence worldwide. Although a deeper understanding of the underlying mechanisms of IBD has led to new therapeutic approaches, treatment options are still limited. Severe adverse events in conventional drug therapy and poor drug targeting are the main cause of early therapy failure. Nanoparticle-based targeting approaches can selectively deliver drugs to the site of inflammation and reduce the risk of side effects by decreasing systemic availability. Here, we developed a nanoparticulate platform for the delivery of the anti-TNF-α antibody adalimumab (ADA) by covalent crosslinking to the particle surface. ADA binding to nanoparticles improved the stability of ADA against proteolytic degradation in vitro and led to a significantly better therapeutic outcome in a murine colitis model. Moreover, immobilization of ADA reduced systemic exposure, which can lead to enhanced therapeutic safety. Thus, nanoparticle protein decoration constitutes a platform through which epithelial delivery of any biological of interest to the inflamed gut and hence a local treatment can be achieved.

12.
Pharmaceutics ; 13(6)2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34201254

RESUMEN

Pharmacologically active macromolecules, such as peptides, are still a major challenge in terms of designing a delivery system for their transport across absorption barriers and at the same time provide sufficiently high long-term stability. Spray freeze dried (SFD) lyospheres® are proposed here as an alternative for the preparation of fast dissolving porous particles for nasal administration of insulin. Insulin solutions containing mannitol and polyvinylpyrrolidone complemented with permeation enhancing excipients (sodium taurocholate or cyclodextrins) were sprayed into a cooled spray tower, followed by vacuum freeze drying. Final porous particles were highly spherical and mean diameters ranged from 190 to 250 µm, depending on the excipient composition. Based on the low density, lyospheres resulted in a nasal deposition rates of 90% or higher. When tested in vivo for their glycemic potential in rats, an insulin-taurocholate combination revealed a nasal bioavailability of insulin of 7.0 ± 2.8%. A complementary study with fluorescently labeled-dextrans of various molecular weights confirmed these observations, leading to nasal absorption ranging from 0.7 ± 0.3% (70 kDa) to 10.0 ± 3.1% (4 kDa). The low density facilitated nasal administration in general, while the high porosity ensured immediate dissolution of the particles. Additionally, due to their stability, lyospheres provide an extremely promising platform for nasal peptide delivery.

13.
Front Microbiol ; 12: 709838, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34290691

RESUMEN

Essential oils (EOs) or their components are widely used by inhalation or nebulization to fight mild respiratory bacterial infections. However, their interaction with antibiotics is poorly known. In this study we evaluated the effects of citral, the main component of lemongrass oil, on in vitro susceptibility of Pseudomonas aeruginosa to antibiotics. Exposure of strain PA14 to subinhibitory concentrations of citral increased expression of operons encoding the multidrug efflux systems MexEF-OprN and MexXY/OprM, and bacterial resistance to anti-pseudomonal antibiotics including imipenem (twofold), gentamicin (eightfold), tobramycin (eightfold), ciprofloxacin (twofold), and colistin (≥128-fold). Use of pump deletion mutants showed that in addition to efflux other mechanisms were involved in this citral-induced phenotype. Determination of Zeta potential suggested that citral impairs the cell surface binding of aminoglycosides and colistin used at low concentrations (≤10 µg/mL). Moreover, experiments based on Raman spectroscopy and high-resolution mass spectrometry demonstrated formation of a Schiff base between the aldehyde group of citral and amino-groups of tobramycin and colistin. Chemical synthesis of tobracitryl, the imine compound resulting from condensation of citral and tobramycin, confirmed the loss of antibiotic activity due to adduct formation. Altogether these data point to the potential risk concern of self-medication with EOs containing citral in patients suffering from P. aeruginosa chronic lung infections and being treated with aerosols of aminoglycoside or colistin.

14.
Biomol Ther (Seoul) ; 29(5): 536-544, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34059563

RESUMEN

5-amino salicylic acid (5-ASA) is a standard therapy for the treatment of mild to moderate forms of inflammatory bowel diseases (IBD) whereas more severe forms involve the use of steroids and immunosuppressive drugs. Hyaluronic acid (HA) is a naturally occurring non-sulfated glycosaminoglycan that has shown epithelium protective effects in experimental colitis recently. In this study, both 5-ASA (30 mg/kg) and HA (15 mg/kg or 30 mg/kg) were administered rectally and investigated for their potential complementary therapeutic effects in moderate or severe murine colitis models. Intrarectal treatment of moderate and severe colitis with 5-ASA alone or HA alone at a dose of 30 mg/kg led to a significant decrease in clinical activity and histology scores, myeloperoxidase activity (MPO), TNF-α, IL-6 and IL-1ß in colitis mice compared to untreated animals. The combination of HA (30 mg/kg) and 5-ASA in severe colitis led to a significant improvement of colitis compared to 5-ASA alone. Combined rectal therapy with HA and 5-ASA could be a treatment alternative for severe cases of IBD as it was the only treatment tested that was not significantly different from the healthy control group. This study further underlines the benefit of searching for yet unexplored drug combinations that show therapeutic potential in IBD without the need of designing completely new drug entities.

15.
Colloids Surf B Biointerfaces ; 205: 111875, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34058691

RESUMEN

Due to their imaging and radiosensitizing properties, ultrasmall gadolinium chelate-coated gold nanoparticles (AuNP) represent a promising approach in the diagnosis and the treatment of tumors. However, their poor pharmacokinetic profile, especially their rapid renal clearance prevents from an efficient exploitation of their potential for medical applications. The present study focuses on a strategy which resides in the encapsulation of AuNP in large polymeric NP to avoid the glomerular filtration and then to prolong the vascular residence time. An original encapsulation procedure using the polyethyleneimine (PEI) was set up to electrostatically entrap AuNP in biodegradable poly(lactic-co-glycolic acid) (PLGA) and polyethylene glycol -PLGA (PLGA-PEG) NP. Hydrodynamic diameters of NP were dependent of the PEI/Au ratio and comprised between 115 and 196 nm for ratios equal or superior to 4. Encapsulation yield was close to 90 % whereas no loading was observed without PEI. No toxicity was observed after 24 h exposure in hepatocyte cell-lines. Entrapement of AuNP in polymeric nanocarriers facilitated the passive uptake in cancer cells after only 2 h incubation. In healthy rat, the encapsulation allowed increasing the gold concentration in the blood within the first hour after intravenous administration. Polymeric nanoparticles were sequestered in the liver and the spleen rather than the kidneys. T1-weighted magnetic resonance demonstrated that encapsulation process did not alter the contrast agent properties of gadolinium. The encapsulation of the gold nanoparticles in PLGA particles paves the way to innovative imaging-guided anticancer therapies in personalized medicine.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Animales , Portadores de Fármacos , Oro , Tamaño de la Partícula , Polietilenglicoles , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Distribución Tisular
16.
Int J Pharm X ; 3: 100080, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33997765

RESUMEN

Findings from recent studies revealed a significant anti-inflammatory effect of polysaccharide-based excipients when formulated with classical drugs in experimental inflammatory bowel disease models. In this study, acacia and guar gum were investigated beyond their typical functionality for a possible additive anti-inflammatory effect when administered with 5-amino salicylic acid (5ASA) in murine experimental colitis. Anti-inflammatory effects of acacia and guar gum-based aqueous suspensions of 5ASA were evaluated in a murine experimental colitis. Acacia or guar gum (30 or 300 mg/kg) were administered via rectal administration alone or in combination with 5ASA (30 mg/kg). Disease activity, myeloperoxidase activity (MPO) and intratissue concentrations of various cytokines were assessed. Both acacia and guar gum separately showed significant effects in reducing the inflammatory markers in murine colitis model in vivo. When combined with the anti-inflammatory drug 5ASA, acacia showed a stronger therapeutic effect than guar gum, especially at the higher dose of acacia (300 mg/kg) which significantly reduced the inflammation in vivo compared to 5ASA alone (MPO, 5ASA: 5743 ± 1334, 5ASA + 30 mg/kg acacia: 3762 ± 2342; 5ASA + 30 mg/kg guar gum: 7373 ± 2115, 5ASA + 300 mg/kg acacia: 3131 ± 1012, 5ASA + 300 mg/kg guar gum: 6358 ± 2379; all U/g tissue). Acacia and guar gum separately showed significant anti-inflammatory effects in murine colitis, and furthermore, high dose acacia led to an additional therapeutic benefit when co-administered with 5ASA. These results indicate that further investigations are surely warranted in the search of better colitis therapy.

17.
Int J Pharm X ; 3: 100076, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33851133

RESUMEN

Using polymers as additives to formulate ternary amorphous solid dispersions (ASDs) has successfully been established to increase the bioavailability of poorly soluble drugs, when one polymer is not able to provide both, stabilizing the drug in the matrix and the supersaturated solution. Therefore, we investigated the influence of low-viscosity hydroxypropyl cellulose (HPC) polymers as an additive in HPMC based ternary ASD formulations made by hot-melt extrusion (HME) on the bioavailability of itraconazole (ITZ). The partitioning potential of the different HPC grades was screened in biphasic supersaturation assays. Solid-state analytics were performed using differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD). The addition of HPCs, especially HPC-UL, resulted in a superior partitioned amount of ITZ in biphasic supersaturation assays. Moreover, the approach in using HPCs as an additive in HPMC based ASDs led to an increase in partitioned ITZ compared to Sporanox® in biorelevant biphasic dissolution studies. The results from the biphasic dissolution experiments correlated well with the in vivo studies, which revealed the highest oral bioavailability for the ternary ASD comprising HPC-UL and HPMC.

18.
Int J Pharm ; 603: 120648, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33915180

RESUMEN

The influence of supersaturation and solubilization on oral absorption was assessed independently from the dissolution process for the non-formulated model drugs celecoxib and telmisartan. In vitro, physicochemical characterization and biphasic dissolution were used to characterize the supersaturation and solubilization effects of three water soluble polymers (copovidone, methylcellulose and Soluplus®) on the drugs. While celecoxib precipitated in a crystalline form resulting in pronounced stabilization of supersaturation, telmisartan precipitated as a highly energetic amorphous form and the potential of the polymers to enhance its solubility was subsequently, limited. In vivo, for the crystalline precipitating celecoxib, supersaturation and solubilization increased its oral bioavailability up to 10-fold. On the contrary, the amorphous precipitating telmisartan did not benefit from the limited stabilization in terms of oral exposure. Amongst all investigated in vitro tests the biphasic dissolution test was the most predictive in relation to supersaturation. However, for the potential micellar solubilization and the respective impact in the aqueous/organic interface, prediction accuracy of the biphasic dissolution test was limited in combination with Soluplus®. Despite the hetergeneous micellar distribution in vitro and permeation in vivo, the biphasic approach could clearly show the supersaturation potential on bioavailability (BA) for celecoxib on the one hand and the inferiority of supersaturation on BA for telmisartan.


Asunto(s)
Micelas , Polímeros , Disponibilidad Biológica , Tracto Gastrointestinal , Solubilidad
19.
Eur Neuropsychopharmacol ; 46: 56-67, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33531260

RESUMEN

Anxio-depressive symptoms as well as severe cognitive dysfunction including aberrant decision-making (DM) are documented in neuropsychiatric patients with hypercortisolaemia. Yet, the influence of the hypothalamo-pituitary-adrenal (HPA) axis on DM processes remains poorly understood. As a tractable mean to approach this human condition, adult male C57BL/6JRj mice were chronically treated with corticosterone (CORT) prior to behavioural, physiological and neurobiological evaluation. The behavioural data indicate that chronic CORT delays the acquisition of contingencies required to orient responding towards optimal DM performance in a mouse Gambling Task (mGT). Specifically, CORT-treated animals show a longer exploration and a delayed onset of the optimal DM performance. Remarkably, the proportion of individuals performing suboptimally in the mGT is increased in the CORT condition. This variability seems to be better accounted for by variations in sensitivity to negative rather than to positive outcome. Besides, CORT-treated animals perform worse than control animals in a spatial working memory (WM) paradigm and in a motor learning task. Finally, Western blotting neurobiological analyses show that chronic CORT downregulates glucocorticoid receptor expression in the medial Prefrontal Cortex (mPFC). Besides, corticotropin-releasing factor signalling in the mPFC of CORT individuals negatively correlates with their DM performance. Collectively, this study describes how chronic exposure to glucocorticoids induces suboptimal DM under uncertainty in a mGT, hampers WM and motor learning processes, thus affecting specific emotional, motor, cognitive and neurobiological endophenotypic dimensions relevant for precision medicine in biological psychiatry.


Asunto(s)
Glucocorticoides , Sistema Hipófiso-Suprarrenal , Animales , Corticosterona/metabolismo , Corticosterona/farmacología , Glucocorticoides/metabolismo , Glucocorticoides/farmacología , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Psicológico/psicología
20.
Drug Deliv Transl Res ; 11(3): 1301-1308, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32794147

RESUMEN

Lipoproteins are biodegradable and biocompatible natural carriers that can be utilized for the transport of hydrophobic drugs, such as cyclosporin A (CycloA), a calcineurin inhibitor utilized for the inflammatory bowel disease, such as ulcerative colitis. A major limitation in the drug treatment of inflammatory bowel disease is the inability to deliver the drug selectively toward the inflamed tissues. Nanotechnology-based drug delivery systems have led to an amelioration of the therapeutic selectivity, but still the majority of the entrapped drug is eliminated without exercising a therapeutic effect. The present study aimed to prepare three lipoprotein formulations (HDL-, LDL-, and VLDL-based) loaded with cyclosporin A for the treatment of colitis in a murine model. After an intravenous injection of a drug dose of 2 mg/kg, clinical activity (colon weight/length ratio) and therapeutic effects (evaluated by the inflammatory markers MPO and TNF-α) were compared with those of the untreated colitis control group. All CycloA-containing lipoproteins reduced clinical activity, with a significant decrease in the case of LDL-CycloA formulation, which also led to the higher therapeutic effect.


Asunto(s)
Colitis Ulcerosa , Colitis , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis Ulcerosa/tratamiento farmacológico , Colon , Ciclosporina , Lípidos , Ratones
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