Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Publication year range
1.
Gastroenterol. hepatol. (Ed. impr.) ; 44(5): 355-365, May.2021. tab, graf
Article in English | IBECS | ID: ibc-221654

ABSTRACT

Objective: Non-alcoholic fatty liver disease (NAFLD) is an aberrant lipid metabolism disease. Hypoxia inducible factor-1 (HIF-1α) is a transcription factor which plays an important part in adapting lower oxygen condition. Here, we aimed to clarify the relationship between HIF-1α and NAFLD. Methods: HepG2 cells was stimulated by oleic acid (OA) and palmitic acid (PA) to establish in vitro model of NAFLD. The expression of lipid metabolism-related genes, the binding of PPARα to HIF-1α promoter, the lipid deposition, and oxidative stress were detected by qRT-PCR, western blot, Chip assay, Oil Red O staining and ELISA assays, respectively. Results: HIF-1α silence promoted lipid accumulation in NAFLD cells, accompanying by the significantly increased contents of TG (triglyceride) and ApoB (apolipoprotein B). In HepG2 cells treated with OA/PA, the expression of lipid metabolism-related genes and proteins, including APOE, A2m, TNFRSF11B, LDLr, and SREBP2, and the intracellular lipid deposition were up-regulated and further aggravated after silencing HIF-1α. In addition, the loss of HIF-1α could remarkably elevate MDA contents while inhibit the activities of beneficial antioxidant enzymes SOD and GSH-Px to activate oxidative stress, and promote the secretion of pro-inflammatory IL-6 and TNF-α to aggravate inflammation in NDFLD cells. PPARα positively bound to HIF-1α promoter. The silence of PPARα aggravated lipid deposition under normal or hypoxic environment in NAFLD cells. In addition, PPAR-α silence could decrease the expression of HIF-1α and ANGPTL4 in NAFLD cell model; moreover, the expression of APOE, A2m and TNFRSF11B and the production of TG and MDA were increased by PPAR-α suppression. Conclusion: HIF-1α plays a crucial role in the regulation of lipid metabolism through activating PPAR-α/ANGPTL4 signaling pathway in NAFLD.(AU)


Objetivo: La esteatohepatitis no alcohólica (EHNA) es una enfermedad del metabolismo aberrante de los lípidos. El factor inducible por hipoxia 1 (HIF-1α) es un factor de transcripción que desempeña una función importante en la adaptación de la afección de nivel de oxígeno bajo. En el presente documento, intentamos aclarar la relación entre HIF-1α y la EHNA. Métodos: Las células HepG2 se estimularon con ácido oleico (OA) y ácido palmítico (PA) para establecer un modelo in vitro de la EHNA. La expresión de los genes relacionados con el metabolismo de los lípidos, la unión de PPARα al promotor HIF-1α, el depósito de lípidos y el estrés oxidativo se detectaron mediante ensayos de qRT-PCR, inmunoelectrotransferencia, ensayo de inmunoprecipitación de cromatina (ChIP), ensayos de tinción de rojo aceite O y ELISA, respectivamente. Resultados: El silencio de HIF-1α promovió la acumulación de lípidos en las células de la EHNA, acompañada de un aumento significativo del contenido de triglicéridos (TG) y apolipoproteína B (ApoB). En las células HepG2 tratadas con OA/PA, la expresión de genes y proteínas relacionados con el metabolismo lipídico, incluidos APOE, A2m, TNFRSF11B, LDLr y SREBP2, y el depósito de lípidos intracelular se regularon al alza y se agravaron aún más después de silenciar HIF-1α. Además, la pérdida de HIF-1α podría elevar notablemente el contenido de MDA e inhibir las actividades de las enzimas antioxidantes beneficiosas SOD y GSH-Px para activar el estrés oxidativo, y promover la secreción de IL-6 pro-inflamatoria y TNF-α para agravar la inflamación en las células de la EHNA. PPARα se unió positivamente al promotor HIF-1α. El silencio de PPARα agravó el depósito de lípidos en un ambiente normal o hipóxico en las células de la EHNA. Además, el silencio de PPAR-α pudo disminuir la expresión de HIF-1α y ANGPTL4 en el modelo de células de la EHNA; por otra parte, la expresión de APOE, A2m y TNFRSF11B, y la producción de TG y MDA aumentaro,


Subject(s)
Humans , Angiopoietin-Like Protein 4/antagonists & inhibitors , Cells, Cultured , Gene Silencing , Hypoxia-Inducible Factor 1/genetics , Non-alcoholic Fatty Liver Disease
2.
Ann Transplant ; 26: e924461, 2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33397838

ABSTRACT

BACKGROUND Enterovirus 71 (EV71) is the pathogen most likely to cause HFMD in young children (1-5 years old). A small number of virion protein (VP) vaccine candidates are considered as the protective molecules in EV71 models. This study aimed to observe comprehensive immunogenicity for a promising EV71 vaccine depending on VP1 in neonatal mouse EV71 models. MATERIAL AND METHODS VP1 was isolated from patients and associated peptides were synthesized. EV71 particles were inactivated and mixed with Freund's complete adjuvant to prepare peptide vaccines. An EV71 vaccine was administered to establish the mouse model and the mice were infected with EV71. Hematoxylin and eosin staining was used to examine inflammatory response in EV71-infected neonatal mice. A semi-quantitative reverse transcription-polymerase chain reaction assay was performed to evaluate the levels of EV71 virus in skeletal muscle, small intestines, and brain tissues. RESULTS Three peptides were selected from 20 VP1 peptides due to their exhibition of the highest immunogenicity. The peptide injection improved inflammation and decreased EV71 particle levels in muscle, small intestines, and brain tissues. The injection also decreased lesions in the small intestines of EV71-infected mice and protected brain tissues from the EV71 infection. CONCLUSIONS The present study confirmed the immuno-protective effects of VP1 vaccine transplantation in mice infected with EV71 virus. Our results provide valuable information that can be used in further studies investigating the specific mechanism of the anti-EV71 vaccine.


Subject(s)
Enterovirus A, Human , Enterovirus Infections/prevention & control , Viral Vaccines , Animals , Animals, Newborn , Antibodies, Neutralizing , Antibodies, Viral , Enterovirus A, Human/immunology , Mice , Vaccines, Virus-Like Particle , Virion
3.
Gastroenterol Hepatol ; 44(5): 355-365, 2021 May.
Article in English, Spanish | MEDLINE | ID: mdl-33272734

ABSTRACT

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is an aberrant lipid metabolism disease. Hypoxia inducible factor-1 (HIF-1α) is a transcription factor which plays an important part in adapting lower oxygen condition. Here, we aimed to clarify the relationship between HIF-1α and NAFLD. METHODS: HepG2 cells was stimulated by oleic acid (OA) and palmitic acid (PA) to establish in vitro model of NAFLD. The expression of lipid metabolism-related genes, the binding of PPARα to HIF-1α promoter, the lipid deposition, and oxidative stress were detected by qRT-PCR, western blot, Chip assay, Oil Red O staining and ELISA assays, respectively. RESULTS: HIF-1α silence promoted lipid accumulation in NAFLD cells, accompanying by the significantly increased contents of TG (triglyceride) and ApoB (apolipoprotein B). In HepG2 cells treated with OA/PA, the expression of lipid metabolism-related genes and proteins, including APOE, A2m, TNFRSF11B, LDLr, and SREBP2, and the intracellular lipid deposition were up-regulated and further aggravated after silencing HIF-1α. In addition, the loss of HIF-1α could remarkably elevate MDA contents while inhibit the activities of beneficial antioxidant enzymes SOD and GSH-Px to activate oxidative stress, and promote the secretion of pro-inflammatory IL-6 and TNF-α to aggravate inflammation in NDFLD cells. PPARα positively bound to HIF-1α promoter. The silence of PPARα aggravated lipid deposition under normal or hypoxic environment in NAFLD cells. In addition, PPAR-α silence could decrease the expression of HIF-1α and ANGPTL4 in NAFLD cell model; moreover, the expression of APOE, A2m and TNFRSF11B and the production of TG and MDA were increased by PPAR-α suppression. CONCLUSION: HIF-1α plays a crucial role in the regulation of lipid metabolism through activating PPAR-α/ANGPTL4 signaling pathway in NAFLD.


Subject(s)
Angiopoietin-Like Protein 4/antagonists & inhibitors , Gene Silencing , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Non-alcoholic Fatty Liver Disease/genetics , PPAR alpha/antagonists & inhibitors , Cells, Cultured , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Signal Transduction
4.
AAPS PharmSciTech ; 18(5): 1699-1709, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27714702

ABSTRACT

The aim of this study was to develop a hydrophilic oral controlled release system (CRS) using the amorphous form of gliclazide, a BCS class II compound, listed on the WHO list of essential medicines. For this purpose, spray-dried dispersions (SDDs) of gliclazide were produced using various grades of hydroxypropyl methylcellulose acetate succinate (HPMCAS) or copovidone as carrier under fully automated conditions. The solid-state properties of prepared SDDs were characterized using X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), modulated differential scanning calorimetry (MDSC), and Fourier transform infrared spectroscopy (FTIR). Supersaturated micro-dissolution testing of SDDs in fasted state-simulated intestinal fluid showed prolonged supersaturation state, with solubility increases of 1.5- to 4.0-fold. Solubility and stability characteristics of the most desirable SDDs in terms of relative dissolution area under the curves (AUCs) (AUC(SDD)/AUC(crystalline)) and stable supersaturated state concentration ratio up to 180 min (C180/Cmax) were determined. The optimized gliclazide-SDD amorphous forms were included into matrix tablets with HPMC blends using compaction simulator. Developed matrix systems were subjected to standard USP dissolution testing. Dissolution profiles obtained were linear with different slopes indicating varying rates of dissolution. Six-month storage stability testing was performed, and dissolution profiles remained stable with "similarity factor" (f 2 = 85). Results show that the use of various HPMCAS as a drug carrier in the spray-drying process produces homogeneous single-phase SDDs which are stable and promising for inclusion into HPMC-based hydrophilic matrix systems.


Subject(s)
Gliclazide/chemistry , Delayed-Action Preparations , Drug Carriers/chemistry , Drug Liberation , Methylcellulose/analogs & derivatives , Methylcellulose/chemistry , Pyrrolidines/chemistry , Solubility , Vinyl Compounds/chemistry
5.
Int J Pharm ; 511(2): 957-68, 2016 Sep 25.
Article in English | MEDLINE | ID: mdl-27492020

ABSTRACT

Spray dried dispersions (SDDs) of glipizide, a BCS Class II model drug, were prepared using various grades of hydroxypropyl methylcellulose acetate succinate (HPMCAS) and copovidone S-630 as carriers. The SDDs appeared as a single amorphous phase with up to 60% drug loading level as revealed by X-ray powder diffraction (XRPD), modulated differential scanning calorimetry (mDSC) and scanning electron microscopy (SEM). Supersaturated micro-dissolution testing of various SDDs in fasted state simulated intestinal fluid showed prolonged supersaturation state (up to 180min) with solubility increases of 5.2-13.9 fold relative to crystalline drug under similar conditions. Solubility and stability characteristics of the most desirable SDDs in terms of relative dissolution AUCs (AUC(SDD)/AUC(crystalline)) and supersaturated concentration ratios (C180/Cmax) were determined. Results show that HPMCAS-based SDDs achieve a higher degree of supersaturation compared to Copovidone S-630 and that SDDs comprising HPMCAS-M and HPMCAS-H maintained stable supersaturated concentration. Dissolution data showed that SDD-loaded CR tablets provide stable supersaturated concentration within the hydrated matrix with increased rate and extent of drug dissolution over 24h. Co-existence of HPMCAS and HPMC within the hydrating matrix showed strong suppression of drug crystallization and allowed achievement of zero-order and slow-first order release kinetics.


Subject(s)
Chemistry, Pharmaceutical/methods , Glipizide/chemistry , Glipizide/metabolism , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/metabolism , Solubility , X-Ray Diffraction
6.
J Pharm Pharmacol ; 67(7): 918-38, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25645386

ABSTRACT

OBJECTIVES: This study focuses on the application of hot melt extrusion (HME) to produce solid dispersions containing griseofulvin (GF) and investigates the in-vitro dissolution performance of HME powders and resulting tablet compositions containing HME-processed dispersions. METHODS: Binary, ternary and quaternary dispersions containing GF, enteric polymer (Eudragit L100-55 or AQOAT-LF) and/or vinyl pyrrolidone-based polymer (Plasdone K-12 povidone or S-630 copovidone) were processed by HME. Two plasticizers, triethyl citrate (TEC) and acetyl tributyl citrate (ATBC), were incorporated to aid in melt processing and to modify release of GF in neutral media following a pH-change in dissolution. Products were characterized for GF recovery, degrees of compositional amorphous character, intermolecular interactions and non-sink dissolution performance. KEY FINDINGS: Binary dispersions exhibited lower maximum observed concentration values and magnitudes of supersaturated GF in neutral media dissolution in comparison with the ternary dispersions. The quaternary HME products, 1 : 2 : 1 : 0.6 GF : L100-55 : S-630 : ATBC and GF : AQOAT-LF : K-12 : ATBC, were determined as the most optimal concentration-enhancing compositions due to increased hydrogen bonding of enteric functional groups with carbonyl/acetate groups of vinyl pyrrolidone-based polymers, reduced compositional crystallinity and presence of incorporated hydrophobic plasticizer. CONCLUSIONS: HME products containing combinations of concentration-enhancing polymers can supersaturate and sustain GF dissolution to greater magnitudes in neutral media following the pH-transition and be compressed into immediate-release tablets exhibiting similar dissolution profiles.


Subject(s)
Griseofulvin/chemistry , Polymers/chemistry , Acrylic Resins/chemistry , Citrates/chemistry , Drug Carriers/chemistry , Drug Compounding/methods , Hot Temperature , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Plasticizers/chemistry , Povidone/chemistry , Powders/chemistry , Solubility , Tablets/chemistry
7.
Exp Lung Res ; 41(1): 12-20, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25275819

ABSTRACT

The aim of the study was to investigate the effects of substance P (SP) in hyperoxia-induced lung injury in newborn rats. Thirty-two rat pups were randomly divided into four groups: normoxia/saline, normoxia/SP, hyperoxia/saline and hyperoxia/SP. In a separate set of experiments, the neonatal rat pups were exposed to 21% or >95% O2 for 14 days with or without intraperitoneal administration of SP. On day 14, the animals were sacrificed and the lungs were processed for histology and biochemical analysis. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was used for the detection of apoptosis. Antioxidant capacity was assessed by glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), oxidative stress was assessed by determining the extent of formation of malondialdehyde (MDA), activities of NADPH oxidase activity, and formation of reactive oxygen species (ROS). The activity of phospho-p38 (p-p38) and -ERK1/2 (p-ERK1/2) proteins and expression of NF-E2-related factor 2 (NRF2) were detected by Western blot, and the expression of p-p38 was detected by immunofluorescence analysis. Compared with the hyperoxia treatment, the lung damage was significantly ameliorated following the SP treatment. Furthermore, the lungs from the pups exposed to hyperoxia TUNEL-positive nuclei increased markedly and decreased significantly after SP treatment. The levels of MDA decreased and that of GSH-Px and SOD increased following the SP treatment. The SP treatment significantly suppressed the activity of NADPH oxidase and reduced ROS production. SP stimulation may result in blocking p38 MAPK and ERK signaling pathways, and the activities of p-p38 and p-ERK, and expression of NRF2 decreased following the SP treatment. These findings indicate that SP can ameliorate hyperoxic lung injury through decreasing cell apoptosis, elevating antioxidant activities, and attenuating oxidative stress.


Subject(s)
Bronchopulmonary Dysplasia/prevention & control , Hyperoxia/complications , Neurotransmitter Agents/therapeutic use , Substance P/therapeutic use , Animals , Animals, Newborn , Bronchopulmonary Dysplasia/enzymology , Bronchopulmonary Dysplasia/etiology , Drug Evaluation, Preclinical , Edema/etiology , Edema/prevention & control , Enzyme Activation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Glutathione Peroxidase/metabolism , Hyperoxia/enzymology , Lung/enzymology , Malondialdehyde/metabolism , NF-E2-Related Factor 2/metabolism , Neurotransmitter Agents/pharmacology , Pregnancy , Random Allocation , Rats, Sprague-Dawley , Substance P/pharmacology , Superoxide Dismutase/metabolism
8.
J Pharm Sci ; 104(1): 124-34, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25410968

ABSTRACT

The primary aim of this research was to produce successfully taste masked formulations of Sildenafil Citrate (SC) using hot-melt extrusion (HME) technology. Multiple screw configurations and polymeric carriers were evaluated for their effects on taste masking efficiency, which was assessed by both E-tongue analysis and in vitro dissolution in simulated salivary fluid (SSF, pH 6.8 artificial saliva). The screw configurations were further assessed for their effects on the morphology of the API using PXRD, FT-IR and mid-infrared chemical imaging. It was determined that the screw configuration had a profound effect on the taste masking efficiency of the formulations as a result of altering the physical state of the API. Selected extruded formulations using ethylcellulose (EC) with a pore former were further formulated into orally disintegrating tablets (ODTs), which were optimized by varying the grade and percentage of the superdisintegrant used. An optimized disintegration time of approximately 8 seconds was achieved. The final ODT formulation exhibited excellent taste masking properties with over 85% drug release in gastric media as well as physical tablet properties. Interestingly, friability, which tends to be a common concern when formulating ODTs, was well within the acceptable limits (<1%) for common tablets.


Subject(s)
Drug Carriers/chemistry , Drug Compounding/instrumentation , Excipients/chemistry , Models, Biological , Piperazines/chemistry , Polymers/chemistry , Saliva/chemistry , Sulfonamides/chemistry , Acetates/chemistry , Cellulose/analogs & derivatives , Cellulose/chemistry , Drug Carriers/administration & dosage , Drug Carriers/adverse effects , Equipment Design , Gastric Juice/chemistry , Hot Temperature , Humans , Phosphodiesterase 5 Inhibitors/administration & dosage , Phosphodiesterase 5 Inhibitors/adverse effects , Phosphodiesterase 5 Inhibitors/chemistry , Piperazines/administration & dosage , Piperazines/adverse effects , Povidone/analogs & derivatives , Povidone/chemistry , Purines/administration & dosage , Purines/adverse effects , Purines/chemistry , Sildenafil Citrate , Solubility , Sulfonamides/administration & dosage , Sulfonamides/adverse effects , Surface Properties , Tablets , Taste , Vasodilator Agents/administration & dosage , Vasodilator Agents/adverse effects , Vasodilator Agents/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...