RESUMEN
Endothelial barrier dysfunction leads to increased endothelial permeability and is an early step in the development of vascular inflammatory diseases such as atherosclerosis. Interferon-γ (IFN-γ), a proinflammatory cytokine, is known to cause increased endothelial permeability. However, the mechanisms by which IFN-γ disrupts the endothelial barrier have not been clarified. This study aimed to investigate how IFN-γ impairs the endothelial barrier integrity by specifically examining the roles of caldesmon, adherens junctions (AJs) and p38 mitogen-activated protein (MAP) kinase in IFN-γ-induced endothelial barrier dysfunction. IFN-γ exhibited a biphasic effect on caldesmon localization and both the structural organization and protein expression of AJs. In the early phase (4-8â¯h), IFN-γ induced the formation of peripheral caldesmon bands and discontinuous AJs, while AJ protein expression was unchanged. Interestingly, IFN-γ also stimulated caldesmon phosphorylation, resulting in actin dissociation from caldesmon at 8â¯h. Conversely, changes seen in the late phase (16-24â¯h) included cytoplasmic caldesmon dispersal, AJ linearization and junctional area reduction, which were associated with reduced membrane, cytoskeletal and total AJ protein expression. In addition, IFN-γ enhanced myosin binding to caldesmon at 12â¯h and persisted up to 24â¯h. Furthermore, inhibition of p38 MAP kinase by SB203580 did not reverse either the early or late phase changes observed. These data suggest that IFN-γ may activate signaling molecules other than p38 MAP kinase. In conclusion, our findings enhance the current understanding of how IFN-γ disrupts endothelial barrier function and reveal potential therapeutic targets, such as caldesmon and AJs, for the treatment of IFN-γ-associated vascular inflammatory diseases.
Asunto(s)
Uniones Adherentes/metabolismo , Proteínas de Unión a Calmodulina/metabolismo , Interferón gamma/metabolismo , Actinas/metabolismo , Cadherinas/metabolismo , Línea Celular , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Fosforilación/fisiología , Unión Proteica/fisiología , Transducción de Señal/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Human exposure to aflatoxin is through the diet, and probiotics are able to bind aflatoxin and prevent its absorption in the small intestine. This study aimed to determine the effectiveness of a fermented milk drink containing Lactobacillus casei Shirota (LcS) (probiotic drink) to prevent aflatoxin absorption and reduce serum aflatoxin B1-lysine adduct (AFB1-lys) and urinary aflatoxin M1 concentrations. The present study was a randomised, double-blind, cross-over, placebo-controlled study with two 4-week intervention phases. In all, seventy-one subjects recruited from the screening stage were divided into two groups--the Yellow group and the Blue group. In the 1st phase, one group received probiotic drinks twice a day and the other group received placebo drinks. Blood and urine samples were collected at baseline, 2nd and 4th week of the intervention. After a 2-week wash-out period, the treatments were switched between the groups, and blood and urine samples were collected at the 6th, 8th and 10th week (2nd phase) of the intervention. No significant differences in aflatoxin biomarker concentrations were observed during the intervention. A within-group analysis was further carried out. Aflatoxin biomarker concentrations were not significantly different in the Yellow group. Nevertheless, ANOVA for repeated measurements indicated that AFB1-lys concentrations were significantly different (P=0·035) with the probiotic intervention in the Blue group. The 2nd week AFB1-lys concentrations (5·14 (SD 2·15) pg/mg albumin (ALB)) were significantly reduced (P=0·048) compared with the baseline (6·24 (SD 3·42) pg/mg ALB). Besides, the 4th week AFB1-lys concentrations were significantly lower (P<0·05) with probiotic supplementation than with the placebo. Based on these findings, a longer intervention study is warranted to investigate the effects of continuous LcS consumption to prevent dietary aflatoxin exposure.
Asunto(s)
Aflatoxinas/metabolismo , Exposición a Riesgos Ambientales/prevención & control , Fermentación , Contaminación de Alimentos , Lacticaseibacillus casei , Leche/microbiología , Probióticos , Adulto , Aflatoxina B1/sangre , Aflatoxina M1/orina , Animales , Bebidas , Biomarcadores/metabolismo , Estudios Cruzados , Dieta , Método Doble Ciego , Exposición a Riesgos Ambientales/análisis , Femenino , Humanos , Lisina/sangre , Malasia , Masculino , Adulto JovenRESUMEN
BACKGROUND: Muntingia calabura L. (family Muntingiaceae), commonly known as Jamaican cherry or kerukup siam in Malaysia, is used traditionally to treat various ailments. The aim of this study is to elucidate the possible underlying gastroprotective mechanisms of ethyl acetate fraction (EAF) of Muntingia calabura methanolic leaves extract (MEMC). METHODS: MEMC and its fractions were subjected to HPLC analysis to identify and quantify the presence of its phyto-constituents. The mechanism of gastroptotection of EAF was further investigated using pylorus ligation-induced gastric lesion rat model (100, 250, and 500 mg/kg). Macroscopic analysis of the stomach, evaluation of gastric content parameters such as volume, pH, free and total acidity, protein estimation, and quantification of mucus were carried out. The participation of nitric oxide (NO) and sulfhydryl (SH) compounds was evaluated and the superoxide dismutase (SOD), gluthathione (GSH), catalase (CAT), malondialdehyde (MDA), prostaglandin E2 (PGE2) and NO level in the ethanol induced stomach tissue homogenate was determined. RESULTS: HPLC analysis confirmed the presence of quercetin and gallic acid in EAF. In pylorus-ligation model, EAF significantly (p <0.001) prevent gastric lesion formation. Volume of gastric content and total protein content reduced significantly (p < 0.01 and p < 0.05, respectively), while free and total acidity reduced in the doses of 250 and 500 mg/kg (p <0.001 and p <0.05, respectively). EAF also augmented the mucus content significantly (p < 0.001). Pre-treatment with N-nitro-L-arginine methyl ester (L-NAME) or N-ethylmaleimide (NEM) reversed the gastroprotective activity of EAF. EAF treatment markedly ameliorated the SOD, GSH and CAT activity and PGE2 and NO level while attenuating MDA level, relative to the vehicle group. CONCLUSIONS: In conclusion, the underlying gastroprotective mechanisms of EAF could be associated with the antisecretory, participation of mucus, antiperoxidative, improvement of antioxidant status, modulation of NO and SH compounds, stimulation of PGE2 as well as presence of quercetin and gallic acid.
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Antioxidantes/farmacología , Ácido Gálico/farmacología , Magnoliopsida/química , Extractos Vegetales/farmacología , Quercetina/farmacología , Úlcera Gástrica , Estómago/efectos de los fármacos , Animales , Antiulcerosos/análisis , Antiulcerosos/farmacología , Antiulcerosos/uso terapéutico , Antioxidantes/análisis , Antioxidantes/uso terapéutico , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Ácido Gálico/análisis , Ácido Gálico/uso terapéutico , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Masculino , Malondialdehído/sangre , Moco/metabolismo , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Quercetina/análisis , Quercetina/uso terapéutico , Ratas Sprague-Dawley , Estómago/patología , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/metabolismoRESUMEN
BACKGROUND: Histamine is established as a potent inflammatory mediator and it is known to increased endothelial permeability by promoting gap formation between endothelial cells. Previous studies have shown that aqueous extract of Bixa orellana leaves (AEBO) exhibits antihistamine activity in vivo, yet the mechanism of its action on endothelial barrier function remains unclear. Therefore, the current study aimed to determine the protective effect of AEBO against histamine-induced hyperpermeability in vitro. METHODS: The endothelial protective effect of AEBO was assess using an in vitro vascular permeability assay kit. Human umbilical vein endothelial cells (HUVEC) were used in the current study. HUVEC were pre-treated with AEBO for 12 h before histamine induction. Vascular permeability was evaluated by the amount of FITC-dextran leakage into the lower chamber. In order to elucidate the mechanism of action of AEBO, phospholipase C (PLC) activity, intracellular calcium level, nitric oxide (NO) concentration, cyclic guanosine monophosphate (cGMP) production and protein kinase C (PKC) activity were determined following histamine challenge. RESULTS: Histamine-induced increased HUVEC permeability was significantly attenuated by pretreatment with AEBO in a time- and concentration-dependent manner. Upregulation of PLC activity caused by histamine in HUVEC was suppressed by pretreatment with AEBO. Pretreatment with AEBO also blocked the production of intracellular calcium induced by histamine in HUVEC. In addition, AEBO suppressed the NO-cGMP signaling cascade when HUVEC were challenged with histamine. Moreover, PKC activity was significantly abolished by pretreatment with AEBO in HUVEC under histamine condition. CONCLUSION: In conclusion, the present data suggest that AEBO could suppress histamine-induced increased endothelial permeability and the activity may be closely related with the inhibition of the PLC-NO-cGMP signaling pathway and PKC activity.
Asunto(s)
Bixaceae , Permeabilidad Capilar/efectos de los fármacos , GMP Cíclico/metabolismo , Endotelio Vascular/efectos de los fármacos , Fosfolipasas de Tipo C/metabolismo , Histamina/efectos adversos , Histamina/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Óxido Nítrico/metabolismo , Extractos Vegetales/farmacología , Hojas de la Planta , Transducción de SeñalRESUMEN
Spirulina spp. is a blue-green algae belongs to the family of Oscillatoriaceae, which having diverse biological activity. The aim of this current study was to evaluate and compare the anti-pyretic and anti-inflammatory activity of Spirulina platensis/SP and Spirulina lonar/SL extracts. In the anti-pyretic study, the ability to reduce the rectal temperature of rats induced pyrexia with 2g/kg Brewer's Yeast (BY) was performed. Rats were dosed either 2 or 4 mg/kg SP or SL. Rectal temperature was taken every hour for 8 hours. Results shown that there were significant dose-dependent (p<0.05) reduction of both treatments. However, SP treatment revealed faster reduction in rectal temperature. For anti-inflammatory activity, the reduction in the volume of paw edema induced by Prostaglandin E2 (100 IU/rat intraplantar) was measured. Rats were dosed orally with 2 or 4 mg/kg SP or SL. The paw edema was measured every 30 minutes for 4 hours using plethysmometer. Results had shown a significant dose dependent reduction in diameter of paw edema (p<0.05). The finding suggests that SP and SL extracts have anti-pyretic and anti-inflammatory properties. However, SP was found to be more effective than SL as anti-pyretic and anti-inflammatory agent.
Asunto(s)
Antiinflamatorios/farmacología , Antipiréticos/farmacología , Extractos Vegetales/farmacología , Spirulina , Animales , Temperatura Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , RatasRESUMEN
BACKGROUND: Bixa orellana L. has been traditionally used in Central and South America to treat a number of ailments, including internal inflammation, and in other tropical countries like Malaysia as treatment for gastric ulcers and stomach discomfort. The current study aimed to determine the major chemical constituents of the aqueous extract of B. orellana (AEBO) and to evaluate the antihistamine activity of AEBO during acute inflammation induced in rats. METHODS: Acute inflammation was produced by subplantar injection of 0.1 mL of 0.1% histamine into the right hind paw of each rat in the control and treatment groups. The degree of edema was measured before injection and at the time points of 30, 60, 120, 180, 240 and 300 min after injection. Changes of peritoneal vascular permeability were studied using Evans blue dye as a detector. Vascular permeability was evaluated by the amount of dye leakage into the peritoneal cavity in rats. To evaluate the inhibitory effect of AEBO on biochemical mediators of vascular permeability, the levels of nitric oxide (NO) and vascular endothelial growth factor (VEGF) were determined in histamine-treated paw tissues. The major constituents of AEBO were determined by gas chromatography-mass spectrometry (GC-MS) analysis. RESULTS: AEBO produced a significant inhibition of histamine-induced paw edema starting at 60 min time point, with maximal percentage of inhibition (60.25%) achieved with a dose of 150 mg/kg of AEBO at 60 min time point. Up to 99% of increased peritoneal vascular permeability produced by histamine was successfully suppressed by AEBO. The expression of biochemical mediators of vascular permeability, NO and VEGF, was also found to be downregulated in the AEBO treated group. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the major constituent in AEBO was acetic acid. CONCLUSIONS: The experimental findings demonstrated that the anti-inflammatory activity of AEBO was due to its inhibitory effect on vascular permeability, which was suppressed as a result of the reduced expression of biochemical mediators (NO and VEGF) in tissues. Our results contribute towards the validation of the traditional use of Bixa orellana in the treatment of inflammatory disorders.
Asunto(s)
Ácido Acético/uso terapéutico , Bixaceae/química , Permeabilidad Capilar/efectos de los fármacos , Antagonistas de los Receptores Histamínicos/uso terapéutico , Inflamación/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Ácido Acético/análisis , Ácido Acético/farmacología , Animales , Regulación hacia Abajo , Edema/tratamiento farmacológico , Edema/metabolismo , Histamina/metabolismo , Histamina/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Inflamación/metabolismo , Masculino , Óxido Nítrico/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta , Ratas , Ratas Sprague-Dawley , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The cytotoxic structure-activity relationships among a series of xanthone derivatives from Mesua beccariana, Mesua ferrea and Mesua congestiflora were studied. Eleven xanthone derivatives identified as mesuarianone (1), mesuasinone (2), mesuaferrin A (3), mesuaferrin B (4), mesuaferrin C (5), 6-deoxyjacareubin (6), caloxanthone C (7), macluraxanthone (8), 1,5-dihydroxyxanthone (9), tovopyrifolin C (10) and α-mangostin (11) were isolated from the three Mesua species. The human cancer cell lines tested were Raji, SNU-1, K562, LS-174T, SK-MEL-28, IMR-32, HeLa, Hep G2 and NCI-H23. Mesuaferrin A (3), macluraxanthone (8) and α-mangostin (11) showed strong cytotoxicities as they possess significant inhibitory effects against all the cell lines. The structure-activity relationship (SAR) study revealed that the diprenyl, dipyrano and prenylated pyrano substituent groups of the xanthone derivatives contributed towards the cytotoxicities.
Asunto(s)
Clusiaceae/química , Xantonas/química , Xantonas/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Quercetina/farmacología , Relación Estructura-ActividadRESUMEN
Abstract Context: Muntingia calabura L. (Muntingiaceae) is a native plant species of the American continent and is widely cultivated in warm areas in Asia, including Malaysia. The plant is traditionally used to relieve pain from gastric ulcers. Objective: This study was designed to determine the antiulcer activity of a methanol extract of M. calabura leaves (MEMC) and the possible mechanisms of action involved. Materials and methods: An acute toxicity study was conducted using a single oral dose of 2000 mg/kg MEMC. The antiulcer activity of MEMC was evaluated in absolute ethanol- and indomethacin-induced gastric ulcer rat models. MEMC was administered orally (dose range 25-500 mg/kg) to rats fasted for 24 h. The animals were pretreated with NG-nitro-l-arginine methyl esters (l-NAME) or N-ethylmaleimide (NEM) prior to MEMC treatment to assess the possible involvement of endogenous nitric oxide (NO) and nonprotein sulfhydryl (NP-SH) compounds in the gastroprotective effect of MEMC. Results: As the administered dose did not cause toxicity in the rats, the oral median lethal dose (LD50) of MEMC was >2000 mg/kg in rats. MEMC exerted significant (p < 0.001) gastroprotective activity in the ethanol- and indomethacin-induced ulcer models dose-dependently. Histological evaluation supported the observed antiulcer activity of MEMC. l-NAME and NEM pretreatment significantly (p < 0.05) reversed and abolished the gastroprotective effect of MEMC, respectively. Discussion and conclusion: The results obtained indicate that MEMC has significant antiulcer activity that might involve the participation of endogenous NO and NP-SH compounds. These findings provide new pharmacological information regarding the potential use of M. calabura.
RESUMEN
Voriconazole is a new, potent broad-spectrum triazole systemic antifungal drug, a second-generation azole antifungal that is increasing in popularity, especially for the treatment of invasive aspergillosis and fluconazole-resistant invasive Candida infections. However, it is also known to induce hepatotoxicity clinically. The aim of this study was to investigate the hepatotoxicity and nephrotoxicity potential of voriconazole in vivo in rats. Forty rats were treated intraperitoneally with voriconazole as single (0, 10, l00, and 200 mg/kg) or repeated (0, 10, 50, and l00 mg/kg per day for 14 days) doses. Venous blood was collected for the repeated-dose group on days 1 and 14. Rats were sacrificed 24 hours after the last dose. Body weight, liver weight, and kidney weight of rats were recorded. Livers and kidneys samples were taken for histological and transmission electron microscopy (TEM) analysis. Results revealed that voriconazole had no effects on serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphotase, gamma glutamyl transpeptidase, blood urea nitrogen, and creatinine for both the single- and repeated-dose groups. However, histologically, in the repeated 50- and 100-mg/kg voriconazole-treated rats, mild focal inflammation was observed. Under TEM, only small changes in the 100 mg/kg/day group were revealed. These results collectively demonstrated that voriconazole did not induce significant hepatotoxicity and nephrotoxicity, even at very high doses.
Asunto(s)
Antifúngicos/efectos adversos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Pirimidinas/efectos adversos , Triazoles/efectos adversos , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Antifúngicos/administración & dosificación , Antifúngicos/química , Aspartato Aminotransferasas/sangre , Nitrógeno de la Urea Sanguínea , Peso Corporal/efectos de los fármacos , Creatinina/sangre , Relación Dosis-Respuesta a Droga , Inyecciones Intraperitoneales , Riñón/patología , Hígado/patología , Microscopía Electrónica de Transmisión , Estructura Molecular , Tamaño de los Órganos/efectos de los fármacos , Pirimidinas/administración & dosificación , Pirimidinas/química , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad/métodos , Triazoles/administración & dosificación , Triazoles/química , Voriconazol , gamma-Glutamiltransferasa/sangreRESUMEN
The amino acid and fatty acid composition of polypeptide k and oil isolated from the seeds of Momordica charantia was analysed. The analysis revealed polypeptide k contained 9 out of 11 essential amino acids, among a total of 18 types of amino acids. Glutamic acid, aspartic acid, arginine and glycine were the most abundant (17.08%, 9.71%, 9.50% and 8.90% of total amino acids, respectively). Fatty acid analysis showed unusually high amounts of C18-0 (stearic acid, 62.31% of total fatty acid). C18-1 (oleic acid) and C18-2 (linoleic acid) were the other major fatty acid detected (12.53% and 10.40%, respectively). The oil was devoid of the short fatty acids (C4-0 to C8-0). Polypeptide k and oil were also subjected to in vitro α-glucosidase and α-amylase inhibition assays. Both polypeptide k and seed oil showed potent inhibition of α-glucosidase enzyme (79.18% and 53.55% inhibition, respectively). α-Amylase was inhibited by 35.58% and 38.02%, respectively. Collectively, the in vitro assay strongly suggests that both polypeptide k and seed oil from Momordica charantia are potent potential hypoglycemic agents.
Asunto(s)
Hipoglucemiantes/farmacología , Momordica charantia/química , Péptidos/farmacología , Aceites de Plantas/farmacología , Semillas/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Péptidos/química , Péptidos/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificaciónRESUMEN
CONTEXT: Conjugated linoleic acids (CLAs) are a mixture of positional and geometric isomers of linoleic acid (LA) and believed to have many positive biological activities. OBJECTIVE: The present study was undertaken to assess the antioxidant activity of cis-9, trans-11 and trans-10, cis-12 as single or mixed CLA isomers at two ratios, 1:6 and 1:13 (trans-10, cis-12/cis-9, trans-11). MATERIALS AND METHODS: A microplate reader was used to determine the free radical scavenging properties of CLAs against DPPH radical in ethanol. RESULTS: The kinetic reactions of CLA-DPPH(â¢) showed that all tested CLAs have exerted radical scavenging activities in a dose-dependent manner and observed to immediately react and quench DPPH radicals at all tested levels and no lag phase was noticed in CLA-DPPH(â¢) reactions. The median inhibitory concentration (IC50) value for cis-9, trans-11 CLA was observed to be more effective than other tested CLA. Total antioxidant capacity (TAC) of all tested CLAs were less effective radical scavengers as compared to vitamin E and butylated hydroxytoluene, although all tested CLAs were quenched a high amount (P < 0.05) of DPPH free radicals. DISCUSSION AND CONCLUSION: All tested CLAs have the ability to directly react and quench DPPH free radicals in ethanol. Furthermore, trans-10, cis-12 CLA has greater maximal efficacy than other tested CLAs as free radical scavenger, while cis-9, trans-11 CLA is the most potent isomer to directly react and quench free radicals at low concentrations in the system, suggesting that the free radical scavenging activity of CLA isomers may contribute to their diverse biological activities.
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Depuradores de Radicales Libres/química , Ácidos Linoleicos Conjugados/química , Anticarcinógenos/química , Antioxidantes/química , Compuestos de Bifenilo/química , Hidroxitolueno Butilado/química , Grasas de la Dieta/análisis , Etanol/química , Indicadores y Reactivos/química , Cinética , Concentración Osmolar , Picratos/química , Solventes/química , Estereoisomerismo , Vitamina E/químicaRESUMEN
Development of early stage atherosclerosis involves the activation of endothelial cells by oxidized low-density lipoprotein (oxLDL) with subsequent increases in endothelial permeability and expression of adhesion molecules favoring the adherence of monocytes to the endothelium. Cryptotanshinone (CTS), a major compound derived from the Chinese herb Salvia miltiorrhiza, is known for its protective effects against cardiovascular diseases. The aim of this study was to determine whether CTS could prevent the oxLDL-induced early atherosclerotic events. OxLDL (100 µg/mL) was used to increase endothelial permeability and induce monocyte-endothelial cell adhesion in human umbilical vein endothelial cells (HUVECs). Endothelial nitric oxide (NO) concentrations, a permeability-regulating molecule, and expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were measured. Results show that a) endothelial hyperpermeability was suppressed by 94â% (p < 0.005), b) monocyte adhesion by 105â% (p < 0.01), and c) ICAM-1 and VCAM-1 expressions by 90â% (p < 0.01) and 150â% (p < 0.005), respectively, when CTS was applied. In contrast, CTS increased NO levels by 129â% (p < 0.01) and was found to be noncytotoxic in the concentrations between 1-10 µM. These findings indicate that CTS suppresses an increase in endothelial permeability, likely due to the restoration of NO bioavailability in endothelial cells. They also indicate that CTS may attenuate monocyte adhesion to endothelial cells through the inhibition of adhesion molecules' expression. Thus, CTS may play an important role in the prevention of early or pre-lesional stage of atherosclerosis.
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Aterosclerosis/prevención & control , Medicamentos Herbarios Chinos/farmacología , Fenantrenos/farmacología , Salvia miltiorrhiza/química , Aterosclerosis/inducido químicamente , Disponibilidad Biológica , Adhesión Celular/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Molécula 1 de Adhesión Intercelular/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Lipoproteínas LDL/toxicidad , Monocitos/efectos de los fármacos , Monocitos/fisiología , Óxido Nítrico/farmacocinética , Permeabilidad/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Endothelial hyperpermeability represents an initiating step in early atherosclerosis and it often occurs as a result of endothelial barrier dysfunction. Asiatic acid, a major triterpene isolated from Centella asiatica (L.) Urban, has previously been demonstrated to protect against tumor necrosis factor (TNF)-α-induced endothelial barrier dysfunction. The present study aimed to investigate the mechanisms underlying the barrier protective effect of asiatic acid in human aortic endothelial cells (HAECs). The localization of F-actin, diphosphorylated myosin light chain (diphospho-MLC), adherens junctions (AJs) and tight junctions (TJs) was studied using immunocytochemistry techniques and confocal microscopy. Their total protein expressions were examined using western blot analysis. The endothelial permeability was assessed using In Vitro Vascular Permeability Assay kits. In addition, intracellular redistribution of the junctional proteins was evaluated using subcellular fractionation kits. We show that asiatic acid stabilized F-actin and diphospho-MLC at the cell periphery and prevented their rearrangement stimulated by TNF-α. However, asiatic acid failed to attenuate cytochalasin D-induced increased permeability. Besides, asiatic acid abrogated TNF-α-induced structural reorganization of vascular endothelial (VE)-cadherin and ß-catenin by preserving their reticulum structures at cell-cell contact areas. In addition, asiatic acid also inhibited TNF-α-induced redistribution of occludin and zona occludens (ZO)-1 in different subcellular fractions. In conclusion, the barrier-stabilizing effect of asiatic acid might be associated with preservation of AJs and prevention of TJ redistribution caused by TNF-α. This study provides evidence to support the potential use of asiatic acid in the prevention of early atherosclerosis, which is initiated by endothelial barrier dysfunction.
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Uniones Adherentes/efectos de los fármacos , Aorta/efectos de los fármacos , Permeabilidad Capilar/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Triterpenos Pentacíclicos/farmacología , Uniones Estrechas/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Actinas/metabolismo , Uniones Adherentes/metabolismo , Aorta/metabolismo , Células Cultivadas , Citoesqueleto/metabolismo , Células Endoteliales/metabolismo , Humanos , Cadenas Ligeras de Miosina/metabolismo , Fosforilación , Estabilidad Proteica , Transducción de Señal , Uniones Estrechas/metabolismoRESUMEN
BACKGROUND: Endothelial cell activation is characterized by increased endothelial permeability and increased expression of cell adhesion molecules (CAMs). This allows monocyte adherence and migration across the endothelium to occur and thereby initiates atherogenesis process. Asiatic acid is a major triterpene isolated from Centella asiatica (L.) Urban and has been shown to possess anti-oxidant, anti-hyperlipidemia and anti-inflammatory activities. PURPOSE: We aimed to investigate protective effects of asiatic acid on tumor necrosis factor-α (TNF-α)-induced endothelial cell activation using human aortic endothelial cells (HAECs). STUDY DESIGN: For cell viability assays, HAECs were treated with asiatic acid for 24 h. For other assays, HAECs were pretreated with various doses of asiatic acid (10-40 µM) for 6 h followed by stimulation with TNF-α (10 ng/ml) for 6 h. METHODS: Fluorescein isothiocyanate (FITC)-dextran permeability assay was performed using commercial kits. Total protein expression of CAMs such as E-selectin, ICAM-1, VCAM-1 and PECAM-1 as well as phosphorylation of IκB-α were determined using western blot. The levels of soluble form of CAMs were measured using flow cytometry. Besides, we also examined the effects of asiatic acid on U937 monocyte adhesion and monocyte migration in HAECs using fluorescent-based assays. RESULTS: Asiatic acid significantly suppressed endothelial hyperpermeability, increased VCAM-1 expression and increased levels of soluble CAMs (sE-selectin, sICAM-1, sVCAM-1 and sPECAM-1) triggered by TNF-α. Neither TNF-α nor asiatic acid affects PECAM-1 expression. However, asiatic acid did not inhibit TNF-α-induced increased monocyte adhesion and migration. Interestingly, asiatic acid suppressed increased phosphorylation of IκB-α stimulated by TNF-α. CONCLUSION: These results suggest that asiatic acid protects against endothelial barrier disruption and this might be associated with the inhibition of NF-κB activation. We have demonstrated a novel protective role of asiatic acid on endothelial function. This reveals the possibility to further explore beneficial effects of asiatic acid on chronic inflammatory diseases that are initiated by endothelial cell activation.
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Células Endoteliales/efectos de los fármacos , Endotelio Vascular/citología , Triterpenos Pentacíclicos/farmacología , Aorta/citología , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Selectina E/metabolismo , Endotelio Vascular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas I-kappa B/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Monocitos/efectos de los fármacos , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Fosforilación , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Células U937 , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
Endothelial dysfunction has been implicated in the pathogenesis of atherosclerosis. Salvia miltiorrhiza (danshen) is a traditional Chinese medicine that has been effectively used to treat cardiovascular disease. Cryptotanshinone (CTS), a major lipophilic compound isolated from S. miltiorrhiza, has been reported to possess cardioprotective effects. However, the anti-atherogenic effects of CTS, particularly on tumor necrosis factor-α (TNF-α)-induced endothelial cell activation, are still unclear. This study aimed to determine the effect of CTS on TNF-α-induced increased endothelial permeability, monocyte adhesion, soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), monocyte chemoattractant protein 1 (MCP-1) and impaired nitric oxide production in human umbilical vein endothelial cells (HUVECs), all of which are early events occurring in atherogenesis. We showed that CTS significantly suppressed TNF-α-induced increased endothelial permeability, monocyte adhesion, sICAM-1, sVCAM-1 and MCP-1, and restored nitric oxide production. These observations suggest that CTS possesses anti-inflammatory properties and could be a promising treatment for the prevention of cytokine-induced early atherogenesis.
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Aterosclerosis/tratamiento farmacológico , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Fenantrenos/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Aterosclerosis/inducido químicamente , Permeabilidad Capilar/efectos de los fármacos , Quimiocina CCL2/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Humanos , Técnicas In Vitro , Molécula 1 de Adhesión Intercelular/fisiología , Monocitos/efectos de los fármacos , Monocitos/fisiología , Óxido Nítrico/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/fisiologíaRESUMEN
The objectives of the present study were to determine the mechanisms of antinociceptive effect of methanol extract of Clinacanthus nutans (Acanthaceae) leaves (MECN) using various animal nociceptive models. The antinociceptive activity of orally administered 10% DMSO, 100 mg/kg acetylsalicylic acid (ASA), 5 mg/kg morphine, or MECN (100, 250, and 500 mg/kg) was determined using the acetic acid-induced abdominal constriction (ACT), formalin-induced paw licking (FT), and hot plate tests (HPT). The role of opioid and nitric oxide/cyclic guanosine monophosphate (NO/cGMP) systems was also investigated. The results showed that MECN produced a significant (p < 0.05) antinociceptive response in all nociceptive models with the recorded ED50 value of 279.3 mg/kg for the ACT, while, for the early and late phases of the FT, the value was >500 mg/kg or 227.7 mg/kg, respectively. This antinociceptive activity was fully antagonized by naloxone (a nonselective opioid antagonist) but was partially reversed by l-arginine (l-arg; a nitric oxide [NO] precursor), Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME; an NO synthase inhibitor), or their combinations thereof. In contrast, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ; a soluble guanylyl cyclase inhibitor) enhanced the extract's antinociception. UHPLC analysis revealed the presence of several flavonoid-based compounds with antinociceptive action. In conclusion, MECN exerted the peripherally and centrally mediated antinociceptive activity via the modulation of the opioid/NO-mediated, but cGMP-independent, systems.
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BACKGROUND: Obesity and overweight are major public health problems. Various factors, such as daily nutritional habits, physical inactivity, and genetic, are related to the prevalence of obesity. Recently, it was revealed that the gut microflora may also play an important role in weight management. Thus, this study aimed to determine the anti-obesity effects of Lactobacillus casei strain Shirota (LcS) compared with those of orlistat in an animal model fed a high-fat diet (HFD). DESIGN: Thirty-two male Sprague-Dawley rats were assigned to four groups fed various diets as follows: a standard diet group, HFD group, HFD supplemented with LcS (108109 colony-forming units (HFD-LcS) group, and HFD group treated with Orlistat (10 mg/kg body weight)). After 15 weeks, the weights of organs, body weight, body fat mass and serological biomarkers were measured. In addition, histological analysis of the liver and adipose tissue was performed. RESULTS: Body weight, body mass index, fat mass, leptin and glucose levels were lower, and high-density lipoprotein and adiponectin levels were higher in the HFD-LcS and HFD-orlistat groups than in the HFD group. In addition a significant difference in body fat mass was observed between HFD-LcS group with HFD-orlistat group (19.19±5.76 g vs. 30.19±7.98 g). Although the interleukin-6 level was significantly decreased in the HFD-LcS and HFD-orlistat groups compared with the HFD group, no significant change was observed in other inflammatory biomarkers. CONCLUSION: The results of the present study show that LcS supplementation improves body weight management and the levels of some related biomarkers. In addition, LcS supplementation showed a better result in fat mass and alanine aminotransferase reduction than Orlistat. Further studies are needed to elucidate the anti-obesity effects of LcS, with a longer period of supplementation.
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Interferon-gamma (IFN-γ) is known to potentiate the progression of inflammatory diseases, such as inflammatory bowel disease and atherosclerosis. IFN-γ has been found to disrupt the barrier integrity of epithelial and endothelial cell both in vivo and in vitro. However, the mechanisms of IFN-γ underlying increased endothelial cell permeability have not been extensively elucidated. We reported that IFN-γ exhibits a biphasic nature in increasing endothelial permeability. The changes observed in the first phase (4-8 h) involve cell retraction and rounding in addition to condensed peripheral F-actin without a significant change in the F-/G-actin ratio. However, cell elongation, stress fiber formation, and an increased F-/G-actin ratio were noticed in the second phase (16-24 h). Consistent with our finding from the permeability assay, IFN-γ induced the formation of intercellular gaps in both phases. A delayed phase of increased permeability was observed at 12 h, which paralleled the onset of cell elongation, stress fiber formation, and increased F-/G-actin ratio. In addition, IFN-γ stimulated p38 mitogen-activated protein (MAP) kinase phosphorylation over a 24 h period. Inhibition of p38 MAP kinase by SB203580 prevented increases in paracellular permeability, actin rearrangement, and increases in the F-/G-actin ratio caused by IFN-γ. Our results suggest that p38 MAP kinase is activated in response to IFN-γ and causes actin rearrangement and altered cell morphology, which in turn mediates endothelial cell hyperpermeability. The F-/G-actin ratio might be involved in the regulation of actin distribution and cell morphology rather than the increased permeability induced by IFN-γ.
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Citoesqueleto de Actina/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/enzimología , Interferón gamma/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Actinas/metabolismo , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Imidazoles , Fosforilación , PiridinasRESUMEN
Probiotics are live microorganisms that exert beneficial effects on the host, when administered in adequate amounts. Mostly, probiotics affect the gastrointestinal (GI) tract of the host and alter the composition of gut microbiota. Nowadays, the incidence of hip fractures due to osteoporosis is increasing worldwide. Ovariectomized (OVX) rats have fragile bone due to estrogen deficiency and mimic the menopausal conditions in women. Therefore, this study aimed to examine the effects of Bifidobacterium longum (B. longum) on bone mass density (BMD), bone mineral content (BMC), bone remodeling, bone structure, and gene expression in OVX rats. The rats were randomly assigned into 3 groups (sham, OVX, and the OVX group supplemented with 1 mL of B. longum 10(8)-10(9) colony forming units (CFU)/mL). B. longum was given once daily for 16 weeks, starting from 2 weeks after the surgery. The B. longum supplementation increased (p < 0.05) serum osteocalcin (OC) and osteoblasts, bone formation parameters, and decreased serum C-terminal telopeptide (CTX) and osteoclasts, bone resorption parameters. It also altered the microstructure of the femur. Consequently, it increased BMD by increasing (p < 0.05) the expression of Sparc and Bmp-2 genes. B. longum alleviated bone loss in OVX rats and enhanced BMD by decreasing bone resorption and increasing bone formation.
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Bifidobacterium/metabolismo , Densidad Ósea/efectos de los fármacos , Densidad Ósea/genética , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Proteína Morfogenética Ósea 2/genética , Osteonectina/genética , Probióticos/farmacología , Animales , Enfermedades Óseas Metabólicas/genética , Enfermedades Óseas Metabólicas/metabolismo , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/genética , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/genética , Resorción Ósea/metabolismo , Femenino , Fémur/efectos de los fármacos , Fémur/metabolismo , Fracturas Óseas/tratamiento farmacológico , Fracturas Óseas/genética , Fracturas Óseas/metabolismo , Osteocalcina/genética , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Osteoporosis/tratamiento farmacológico , Osteoporosis/genética , Osteoporosis/metabolismo , Ovariectomía/efectos adversos , Ratas , Ratas Sprague-DawleyRESUMEN
PURPOSE: Nonsteroidal anti-inflammatory drugs (NSAIDs) are used for the treatment of many joint disorders, inflammation and to control pain. Numerous reports have indicated that NSAIDs are capable of producing nephrotoxicity in human. Therefore, the objective of this study was to evaluate mefenamic acid, a NSAID nephrotoxicity in an animal model. METHODS: Mice were dosed intraperitoneally with mefenamic acid either as a single dose (100 or 200 mg/kg in 10% Dimethyl sulfoxide/Palm oil) or as single daily doses for 14 days (50 or 100 mg/kg in 10% Dimethyl sulfoxide/Palm oil per day). Venous blood samples from mice during the dosing period were taken prior to and 14 days post-dosing from cardiac puncture into heparinized vials. Plasma blood urea nitrogen (BUN) and creatinine activities were measured. RESULTS: Single dose of mefenamic acid induced mild alteration of kidney histology mainly mild glomerular necrosis and tubular atrophy. Interestingly, chronic doses induced a dose dependent glomerular necrosis, massive degeneration, inflammation and tubular atrophy. Plasma blood urea nitrogen was statistically elevated in mice treated with mefenamic acid for 14 days similar to plasma creatinine. CONCLUSION: RESULTS from this study suggest that mefenamic acid as with other NSAIDs capable of producing nephrotoxicity. Therefore, the study of the exact mechanism of mefenamic acid induced severe nephrotoxicity can be done in this animal model.