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1.
Int J Mol Sci ; 22(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668543

RESUMO

Chrysin (CHR) is a natural flavonoid with a wide range of pharmacological activities, including hepatoprotection, but poor water solubility. By including water-soluble hydroxypropyl (HPBCD) and randomly methylated (RAMEB) ß-cyclodextrin, we aimed to increase its biodisponibility and the effectiveness of the antifibrotic effects of chrysin at oral administration. Liver fibrosis in mice was induced in 7 weeks by CCl4 i.p. administration, and afterwards treated with 50 mg/kg of CHR-HPBCD, CHR-RAMEB, and free chrysin. CCl4 administration increased hepatic inflammation (which was augmented by the upregulation of nuclear factor kappa-light-chain enhancer of activated B cells (NF-kB), tumor necrosis factor (TNF)-α, and interleukin 6 (IL-6) and induced fibrosis, as determined using histopathology and electron microscopy. These results were also confirmed by the upregulation of Collagen I (Col I) and matrix metalloproteinase (MMP) expression, which led to extracellular fibrotic matrix proliferation. Moreover, the immunopositivity of alpha-smooth muscle actin (a-SMA) in the CCl4 group was evidence of hepatic stellate cell (HSC) activation. The main profibrotic pathway was activated, as confirmed by an increase in the transforming growth factor- ß1 (TGF-ß1) and Smad 2/3 expression, while Smad 7 expression was decreased. Treatment with CHR-HPBCD and CHR-RAMEB considerably reduced liver injury, attenuated inflammation, and decreased extracellular liver collagen deposits. CHR-RAMEB was determined to be the most active antifibrotic complex. We conclude that both nanocomplexes exert anti-inflammatory effects and antifibrotic effects in a considerably stronger manner than for free chrysin administration.


Assuntos
Flavonoides/farmacologia , Cirrose Hepática , MicroRNAs/biossíntese , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , beta-Ciclodextrinas/farmacologia , Animais , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , MicroRNAs/genética , NF-kappa B/genética , Transdução de Sinais/genética , Proteínas Smad/genética , Fator de Crescimento Transformador beta1/genética
2.
Rev Sci Instrum ; 92(1): 015120, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514212

RESUMO

In this work, we report the development of a measurement chamber linked with a quadrupole mass spectrometer (QMS) for in situ investigation of the effect of thin film cracking on the gas permeation of coated flexible polymeric substrates. The chamber enables the establishment of a bulged state of the substrate/coating system, which causes the cracking of the coating layer. The increase in the gas permeation rate due to the presence of cracks can be monitored precisely using the QMS without movement or re-clamping of the samples between each measurement step. This method eliminates the probability of uncontrollable mechanical changes in the sample, and with the mass spectrometer, high sensitivity, reliability, and reproducibility of the experimental data become available.

3.
Front Pharmacol ; 9: 883, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30150935

RESUMO

Silymarin (Sy) shows limited water solubility and poor oral bioavailability. Water-soluble hydroxypropyl (HPBCD) and randomly methylated (RAMEB) ß-cyclodextrins were designed to enhance anti-fibrotic efficiency of silymarin in CCl4-induced liver fibrosis in mice. Experimental fibrosis was induced by intraperitoneal injection with 2 ml/kg CCl4 (20% v/v) twice a week, for 7 weeks. Mice were orally treated with 50 mg/kg of Sy-HPBCD, Sy-RAMEB and free silymarin. For assessment of the spontaneous reversion of fibrosis, CCl4 treated animals were investigated after 2 weeks of recovery time. The CCl4 administration increased hepatic oxidative stress, augmented the expression of transforming growth factor-ß1 (TGF-ß1) and Smad 2/3, and decreased Smad 7 expression. Furthermore, increased α-smooth muscle actin (α-SMA) expression indicated activation of hepatic stellate cells (HSCs), while up-regulation of collagen I (Col I) and matrix metalloproteinases (MMPs) expression led to an altered extracellular matrix enriched in collagen, confirmed as well by trichrome staining and electron microscopy analysis. Treatment with Sy-HPBCD and Sy-RAMEB significantly reduced liver injury, attenuating oxidative stress, restoring antioxidant balance in the hepatic tissue, and significantly decreasing collagen deposits in the liver. The levels of pro-fibrogenic markers' expression were also significantly down-regulated, whereas in the group for spontaneous regression of fibrosis, they remained significantly higher, even at 2 weeks after CCl4 administration was discontinued. The recovery was significantly lower for free silymarin group compared to silymarin/ß cyclodextrins co-treatments. Sy-HPBCD was found to be the most potent anti-fibrotic complex. We demonstrated that Sy-HPBCD and Sy-RAMEB complexes decreased extracellular matrix accumulation by inhibiting HSC activation and diminished the oxidative damage. This might occur via the inhibition of TGF-ß1/Smad signal transduction and MMP/tissue inhibitor of MMPs (TIMP) rebalance, by blocking the synthesis of Col I and decreasing collagen deposition. These results suggest that complexation of silymarin with HPBCD or RAMEB represent viable options for the its oral delivery, of the flavonoid as a potential therapeutic entity candidate, with applications in the treatment of liver fibrosis.

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