RESUMEN
End-stage renal disease (ESRD) patients present high levels of phosphorus and calcium products in serum, which contribute to the development of vascular calcification and cardiovascular disease, and to low iron stores and carnitine deficiency. For these reasons, ESRD patients are generally supplemented with different medicines. Some of the most common treatments include the use of Carnicor, Venofer, and Sevelamer drugs. Carnicor is used as a source of L-carnitine, acting as antioxidant and neuroprotector. Venofer is used to reduce the deficit of iron. Sevelamer is used to treat hyperphosphatemia. To determine the potential harmful genotoxic effects of these drugs, a group of 214 patients included in a hemodialysis program with different intakes of Carnicor, Venofer, and Sevelamer were evaluated. The levels of basal and oxidative DNA damage, as well as chromosomal damage, were measured in all individuals using the comet and the micronucleus assays, respectively. Our results indicate that Carnicor administration was associated with low but significant increases in the frequency of basal DNA damage and micronuclei. Environ. Mol. Mutagen. 59:302-311, 2018. © 2018 Wiley Periodicals, Inc.
Asunto(s)
Carnitina/farmacología , Daño del ADN/efectos de los fármacos , Compuestos Férricos/farmacología , Ácido Glucárico/farmacología , Fallo Renal Crónico , Linfocitos/efectos de los fármacos , Sevelamer/farmacología , Quelantes/farmacología , Ensayo Cometa , Femenino , Sacarato de Óxido Férrico , Hematínicos/farmacología , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/tratamiento farmacológico , Masculino , Pruebas de Micronúcleos , Persona de Mediana Edad , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacosRESUMEN
BACKGROUND: Over the past two decades, saccharolactone has been routinely used in in vitro microsomal incubations, and sometimes in incubations with recombinant Uridine diphosphoglucuronosyl transferases (UGT) while investigating glucuronidation reactions. The addition of saccharolactone is aimed at completely inhibiting ß-glucuronidases that may be present in the microsomes, in the anticipation of accurate identification and quantification of the formed glucuronide metabolites. Recent research has demonstrated that saccharolatone may not serve the intended objective, and may even lead to inhibition of certain UGTs. OBJECTIVE: This report investigates the historic evidence in the practice of saccharolactone addition in relation to ß- glucuronidases and UGTs. The chemical nature and inhibition potency of saccharolactone are explored in an attempt to unravel the myth in its application. Finally, the collective evidence is discussed in an effort to provide guidance to drug metabolism scientists on the utilization of saccharolactone. CONCLUSION: In-depth evaluation of the experimental evidence in the literature points toward a weak rationale for general in vitro application of saccharolactone. Furthermore, inhibition of recombinant or microsomal UGTs by saccharolactone may be model dependent. Overall, the integrated data suggests that saccharolactone should not be utilized in in vitro microsomal incubations with the objective of inhibiting ß-glucuronidases.
Asunto(s)
Ácido Glucárico/análogos & derivados , Glucuronosiltransferasa/antagonistas & inhibidores , Glucuronosiltransferasa/metabolismo , Microsomas/efectos de los fármacos , Ácido Glucárico/farmacología , Humanos , Microsomas/metabolismoRESUMEN
Olive oil vascular benefits have been attributed to hydroxytyrosol (HT). However, HT biological actions are still debated because it is extensively metabolized into glucuronides (GCs). The aim of this study was to test HT and GC vasculoprotective effects and the underlying mechanisms using aorta rings from 8-week-old male Wistar rats. In the absence of oxidative stress, incubation with 100 µM HT or GC for 5 min did not exert any vasorelaxing effect and did not influence the vascular function. Conversely, in condition of oxidative stress [upon incubation with 500 µM tert-butylhydroperoxide (t-BHP) for 30 min], preincubation with HT or GC improved acetylcholine-induced vasorelaxation compared with untreated samples (no t-BHP). This protective effect was lost for GC, but not for HT, when a washing step (15 min) was introduced between preincubation with HT or GC and t-BHP addition, suggesting that only HT enters the cells. In agreement, bilitranslocase inhibition with 100 µM phenylmethanesulfonyl fluoride for 20 min reduced significantly HT, but not GC, effect on the vascular function upon stress induction. Moreover, GC protective effect (improvement of endothelium-dependent relaxation in response to acetylcholine) in oxidative stress conditions was reduced by preincubation of aorta rings with 300 µM D-saccharolactone to inhibit ß-glucuronidase, which can deconjugate polyphenols. Finally, only HT was detected by high-pressure liquid chromatography in aorta rings incubated with GC and t-BHP. These results suggest that, in conditions of oxidative stress, GC can be deconjugated into HT that is transported through the cell membrane by bilitranslocase to protect vascular function.
Asunto(s)
Antioxidantes/metabolismo , Ceruloplasmina/metabolismo , Endotelio Vascular/metabolismo , Glucuronidasa/metabolismo , Glucurónidos/metabolismo , Estrés Oxidativo , Alcohol Feniletílico/análogos & derivados , Animales , Antioxidantes/química , Aorta Torácica , Transporte Biológico Activo/efectos de los fármacos , Ceruloplasmina/antagonistas & inhibidores , Suplementos Dietéticos , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/enzimología , Inhibidores Enzimáticos/farmacología , Ácido Glucárico/análogos & derivados , Ácido Glucárico/farmacología , Glucuronidasa/antagonistas & inhibidores , Glucurónidos/química , Técnicas In Vitro , Masculino , Moduladores del Transporte de Membrana/farmacología , Oxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Alcohol Feniletílico/química , Alcohol Feniletílico/metabolismo , Fluoruro de Fenilmetilsulfonilo/farmacología , Ratas Wistar , Enfermedades Vasculares/enzimología , Enfermedades Vasculares/metabolismo , Enfermedades Vasculares/prevención & control , Vasodilatación/efectos de los fármacos , terc-Butilhidroperóxido/farmacologíaRESUMEN
Pharmacological doses (> 1mM) of ascorbate (a.k.a., vitamin C) have been shown to selectively kill cancer cells through a mechanism that is dependent on the generation of H2O2 at doses that are safely achievable in humans using intravenous administration. The process by which ascorbate oxidizes to form H2O2 is thought to be mediated catalytically by redox active metal ions such as iron (Fe). Because intravenous iron sucrose is often administered to colon cancer patients to help mitigate anemia, the current study assessed the ability of pharmacological ascorbate to kill colon cancer cells in the presence and absence of iron sucrose. In vitro survival assays showed that 10mM ascorbate exposure (2h) clonogenically inactivated 40-80% of exponentially growing colon cancer cell lines (HCT116 and HT29). When the H2O2 scavenging enzyme, catalase, was added to the media, or conditionally over-expressed using a doxycycline inducible vector, the toxicity of pharmacological ascorbate was significantly blunted. When colon cancer cells were treated in the presence or absence of 250µM iron sucrose, then rinsed, and treated with 10mM ascorbate, the cells demonstrated increased levels of labile iron that resulted in significantly increased clonogenic cell killing, compared to pharmacological ascorbate alone. Interestingly, when colon cancer cells were treated with iron sucrose for 1h and then 10mM ascorbate was added to the media in the continued presence of iron sucrose, there was no enhancement of toxicity despite similar increases in intracellular labile iron. The combination of iron chelators, deferoxamine and diethylenetriaminepentaacetic acid, significantly inhibited the toxicity of either ascorbate alone or ascorbate following iron sucrose. These observations support the hypothesis that increasing intracellular labile iron pools, using iron sucrose, can be used to increase the toxicity of pharmacological ascorbate in human colon cancer cells by a mechanism involving increased generation of H2O2.
Asunto(s)
Ácido Ascórbico/toxicidad , Compuestos Férricos/farmacología , Ácido Glucárico/farmacología , Hierro/metabolismo , Estrés Oxidativo/efectos de los fármacos , Catalasa/metabolismo , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Deferoxamina/farmacología , Sacarato de Óxido Férrico , Células HCT116 , Células HT29 , Humanos , Peróxido de Hidrógeno/metabolismo , Quelantes del Hierro/farmacologíaRESUMEN
Tin protoporphyrin (SnPP), a heme oxygenase (HO) inhibitor, can paradoxically protect against diverse forms of acute kidney injury (AKI). This study sought potential underlying mechanisms. CD-1 mice received intravenous SnPP, followed 4-18 hours later by a variety of renal biochemical, histologic, and genomic assessments. Renal resistance to ischemic-reperfusion injury (IRI) was also sought. SnPP was rapidly taken up by kidney and was confined to proximal tubules. Transient suppression of renal heme synthesis (decreased δ aminolevulinic acid synthase expression), a 2.5-fold increase in "catalytic" Fe levels and oxidant stress resulted (decreased glutathione; increased malondialdehyde, and protein carbonyl content). Nrf2 nuclear translocation (â¼2x Nrf2 increase; detected by enzyme-linked immunosorbent assay, Western blotting), with corresponding activation of â¼20 Nrf2-sensitive genes (RNA-Seq) were observed. By 18 hours after SnPP injection, marked protection against IRI emerged. This represented "preconditioning", not a direct SnPP effect, given that SnPP administered at the time of IRI exerted no protective effect. The importance of transient oxidant stress in SnPP "preconditioning" was exemplified by the following: (1) oxidant stress induced by a different mechanism (myoglobin injection) recapitulated SnPP's protective action; (2) GSH treatment blunted SnPP's protective influence; (3) SnPP raised cytoprotective heavy chain ferritin (Fhc), a response enhanced by exogenous Fe injection; and (4) SnCl2, a â¼35- to 50-fold HO-1 inducer (not inhibitor) evoked neither oxidant stress nor mitigated IRI (seemingly excluding HO-1 activity in SnPP's protective effect). SnPP specifically accumulates within proximal tubule cells; transient "catalytic" Fe overload and oxidative stress result; Nrf2-cytoprotective pathways are upregulated; and these changes help protect against ischemic AKI.
Asunto(s)
Lesión Renal Aguda/prevención & control , Compuestos Férricos/farmacología , Ácido Glucárico/farmacología , Metaloporfirinas/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Protoporfirinas/farmacología , Animales , Compuestos Férricos/administración & dosificación , Sacarato de Óxido Férrico , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Ácido Glucárico/administración & dosificación , Masculino , Metaloporfirinas/administración & dosificación , Ratones , Factor 2 Relacionado con NF-E2/genética , Oxidantes , Unión Proteica , Protoporfirinas/administración & dosificación , Daño por ReperfusiónRESUMEN
Renal anemia is a major complication in chronic kidney disease (CKD). Iron supplementation, as well as erythropoiesis-stimulating agents, are widely used for treatment of renal anemia. However, excess iron causes oxidative stress via the Fenton reaction, and iron supplementation might damage remnant renal function including erythropoietin (EPO) production in CKD. EPO gene expression was suppressed in mice following direct iron treatment. Hypoxia-inducible factor-2 alpha (HIF-2α), a positive regulator of the EPO gene, was also diminished in the kidney of mice following iron treatment. Anemia-induced increase in renal EPO and HIF-2α expression was inhibited by iron treatment. In in vitro experiments using EPO-producing HepG2 cells, iron stimulation reduced the expression of the EPO gene, as well as HIF-2α. Moreover, iron treatment augmented oxidative stress, and iron-induced reduction of EPO and HIF-2α expression was restored by tempol, an antioxidant compound. HIF-2α interaction with the Epo promoter was inhibited by iron treatment, and was restored by tempol. These findings suggested that iron supplementation reduced EPO gene expression via an oxidative stress-HIF-2α-dependent signaling pathway.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Eritropoyetina/metabolismo , Hierro/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Eritropoyetina/análisis , Compuestos Férricos/farmacología , Sacarato de Óxido Férrico , Fibroblastos , Ácido Glucárico/farmacología , Células Hep G2 , Humanos , Riñón/efectos de los fármacos , Riñón/metabolismo , Ratones , Regulación hacia Arriba/efectos de los fármacos , Obstrucción UreteralRESUMEN
BACKGROUND: Intravenous (IV) iron preparations are widely used in the treatment of anemia in patients undergoing hemodialysis (HD). All IV iron preparations carry a risk of causing hypersensitivity reactions. However, the pathophysiological mechanism is poorly understood. We hypothesize that a relevant number of these reactions are mediated by complement activation, resulting in a pseudo-anaphylactic clinical picture known as complement activation-related pseudo allergy (CARPA). METHODS: First, the in-vitro complement-activating capacity was determined for 5 commonly used IV iron preparations using functional complement assays for the 3 pathways. Additionally, the preparations were tested in an ex-vivo model using the whole blood of healthy volunteers and HD patients. Lastly, in-vivo complement activation was tested for one preparation in HD patients. RESULTS: In the in-vitro assays, iron dextran, and ferric carboxymaltose caused complement activation, which was only possible under alternative pathway conditions. Iron sucrose may interact with complement proteins, but did not activate complement in-vitro. In the ex-vivo assay, iron dextran significantly induced complement activation in the blood of healthy volunteers and HD patients. Furthermore, in the ex-vivo assay, ferric carboxymaltose and iron sucrose only caused significant complement activation in the blood of HD patients. No in-vitro or ex-vivo complement activation was found for ferumoxytol and iron isomaltoside. IV iron therapy with ferric carboxymaltose in HD patients did not lead to significant in-vivo complement activation. CONCLUSION: This study provides evidence that iron dextran and ferric carboxymaltose have complement-activating capacities in-vitro, and hypersensitivity reactions to these drugs could be CARPA-mediated.
Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Activación de Complemento/efectos de los fármacos , Hematínicos/farmacología , Compuestos de Hierro/farmacología , Fallo Renal Crónico/terapia , Administración Intravenosa , Anemia Ferropénica/complicaciones , Complemento C1q/efectos de los fármacos , Complemento C1q/metabolismo , Complemento C3d/efectos de los fármacos , Complemento C3d/metabolismo , Complejo de Ataque a Membrana del Sistema Complemento/efectos de los fármacos , Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Disacáridos/farmacología , Disacáridos/uso terapéutico , Compuestos Férricos/farmacología , Compuestos Férricos/uso terapéutico , Sacarato de Óxido Férrico , Óxido Ferrosoférrico/farmacología , Óxido Ferrosoférrico/uso terapéutico , Ácido Glucárico/farmacología , Ácido Glucárico/uso terapéutico , Hematínicos/uso terapéutico , Humanos , Técnicas In Vitro , Compuestos de Hierro/uso terapéutico , Complejo Hierro-Dextran/farmacología , Complejo Hierro-Dextran/uso terapéutico , Fallo Renal Crónico/complicaciones , Maltosa/análogos & derivados , Maltosa/farmacología , Maltosa/uso terapéutico , Lectina de Unión a Manosa/efectos de los fármacos , Lectina de Unión a Manosa/metabolismo , Properdina/efectos de los fármacos , Properdina/metabolismo , Diálisis RenalRESUMEN
BACKGROUND: Treatment of iron deficiency with intravenous (i.v.) iron is a first-line strategy to improve anaemia of chronic kidney disease. Previous in vitro experiments demonstrated that different i.v. iron preparations inhibit differentiation of haematopoietic stem cells to monocytes, but their effect on monocyte differentiation to macrophages and mature dendritic cells (mDCs) has not been assessed. We investigated substance-specific effects of iron sucrose (IS), sodium ferric gluconate (SFG), ferric carboxymaltose (FCM) and iron isomaltoside 1000 (IIM) on monocytic differentiation to M1/M2 macrophages and mDCs. METHODS: Via flow cytometry and microRNA (miRNA) expression analysis, we morphologically and functionally characterized monocyte differentiation to M1/M2 macrophages and mDCs after monocyte stimulation with IS, SFG, FCM and IIM (0.133, 0.266 and 0.533 mg/mL, respectively). To assess potential clinical implications, we compared monocytic phagocytosis capacity in dialysis patients who received either 500 mg IS or IIM. RESULTS: Phenotypically, IS and SFG dysregulated the expression of macrophage (e.g. CD40, CD163) and mDC (e.g. CD1c, CD141) surface markers. Functionally, IS and SFG impaired macrophage phagocytosis capacity. Phenotypic and functional alterations were less pronounced with FCM, and virtually absent with IIM. In miRNA expression analysis of mDCs, IS dysregulated miRNAs such as miR-146b-5p and miR-155-5p, which are linked to Toll-like receptor and mitogen-activated protein kinase signalling pathways. In vivo, IS reduced monocytic phagocytosis capacity within 1 h after infusion, while IIM did not. CONCLUSIONS: This study demonstrates that less stable i.v. iron preparations specifically affect monocyte differentiation towards macrophages and mDCs.
Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Diferenciación Celular/efectos de los fármacos , Células Dendríticas/citología , Compuestos de Hierro/administración & dosificación , Macrófagos/citología , Monocitos/citología , Anemia Ferropénica/inmunología , Anemia Ferropénica/patología , Estudios de Casos y Controles , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Disacáridos/administración & dosificación , Disacáridos/farmacología , Compuestos Férricos/administración & dosificación , Compuestos Férricos/farmacología , Sacarato de Óxido Férrico , Ácido Glucárico/administración & dosificación , Ácido Glucárico/farmacología , Hematínicos/administración & dosificación , Hematínicos/farmacología , Humanos , Inyecciones Intravenosas , Compuestos de Hierro/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Maltosa/administración & dosificación , Maltosa/análogos & derivados , Maltosa/farmacología , MicroARNs/genética , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Fagocitosis/efectos de los fármacosRESUMEN
Skin cancer is among the most common cancers worldwide and identifiable molecular changes for early and late stage of skin tumorigenesis can suggest the better targets for its control. In this study, we investigated the status of K-Ras-PI3K-AKTpathway followed by NF-κB, cyclin D1, MMP-9 and regulatory micro RNA during 7, 12-dimethylbenz[a]anthracene (DMBA) induced mouse skin tumorigenesis and its prevention by butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG), individually or in combination with respect to time. DMBA upregulated the K-Ras, PI3K, Akt, NF-κB, cyclin D1 and MMP-9, but downregulated the PTEN in a time dependent manner. DMBA also reduced the levels of micoRNA let-7a but induced the levels of miR-21 and miR-20a as a function of time. BA, NA and CAG were found to prevent DMBA induced changes, but they were most effective when used together in a combination. Reduced let-7a and miR-211 were correlated with the overexpression of K-Ras and MMP-9. Overexpression of miR-21 and miR-20a was correlated with the down regulation of PTEN and overexpression of Cyclin D1. Collectively, the enhanced chemopreventive potential of natural compound in combination via regulation of K-Ras-PI3K-AKTpathway along with regulatory micro RNAs provide a newer and effective mean for cancer management.
Asunto(s)
Ácido Butírico/farmacología , Ácido Glucárico/farmacología , MicroARNs/genética , Niacinamida/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Cutáneas/metabolismo , 9,10-Dimetil-1,2-benzantraceno , Animales , Antineoplásicos/farmacología , Western Blotting , Ratones , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Neoplasias Cutáneas/inducido químicamenteRESUMEN
The presence of labile iron fractions in intravenous iron supplements compromises their safety. Poly(ethylene glycol) (PEG)-assisted silica xerogel was evaluated as a potential drug carrier for iron sucrose with the purpose of limiting labile iron available for in vitro uptake by transferrin. The drug entrapped xerogels were synthesized by the sol-gel process with varying amounts of PEG. In vitro release studies were conducted in simulated body fluid (SBF) at 37 ± 0.02 °C (pH 7.4). The results indicated that the cumulative release percentage increased with the increase in the amount of PEG in the matrix. The biphasic release profile followed first-order kinetics for the first 6 h and Higuchi model for the remaining time (up to 168 h). The sample showing highest percentage of cumulative release (the xerogel with 16 % PEG) was used for in vitro transferrin saturation studies in contrast with the plain drug. The xerogel formulation exhibited 7.25 ± 0.4 % transferrin saturation in 180 min as compared to 12.89 ± 0.2 % for the raw drug. These results indicate that encapsulation of iron sucrose in PEG-assisted silica xerogel and subsequent sustained release from the matrix can improve the safety of the drug when presence of labile iron is a major concern.
Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Geles/farmacología , Transferrina/metabolismo , Liberación de Fármacos , Compuestos Férricos/química , Compuestos Férricos/farmacología , Sacarato de Óxido Férrico , Geles/química , Ácido Glucárico/química , Ácido Glucárico/farmacología , Humanos , Cinética , Polietilenglicoles/química , Polietilenglicoles/farmacología , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Transferrina/efectos de los fármacosRESUMEN
The POU4F2/Brn-3b transcription factor has been identified as a potentially novel regulator of key metabolic processes. Loss of this protein in Brn-3b knockout (KO) mice causes profound hyperglycemia and insulin resistance (IR), normally associated with type 2 diabetes (T2D), whereas Brn-3b is reduced in tissues taken from obese mice fed on high-fat diets (HFD), which also develop hyperglycemia and IR. Furthermore, studies in C2C12 myocytes show that Brn-3b mRNA and proteins are induced by glucose but inhibited by insulin, suggesting that this protein is itself highly regulated in responsive cells. Analysis of differential gene expression in skeletal muscle from Brn-3b KO mice showed changes in genes that are implicated in T2D such as increased glycogen synthase kinase-3ß and reduced GLUT4 glucose transporter. The GLUT4 gene promoter contains multiple Brn-3b binding sites and is directly transactivated by this transcription factor in cotransfection assays, whereas chromatin immunoprecipitation assays confirm that Brn-3b binds to this promoter in vivo. In addition, correlation between GLUT4 and Brn-3b in KO tissues or in C2C12 cells strongly supports a close association between Brn-3b levels and GLUT4 expression. Since Brn-3b is regulated by metabolites and insulin, this may provide a mechanism for controlling key genes that are required for normal metabolic processes in insulin-responsive tissues and its loss may contribute to abnormal glucose uptake.
Asunto(s)
Diabetes Mellitus Tipo 2/genética , Proteínas de Homeodominio/genética , Hiperglucemia/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , ARN Mensajero/metabolismo , Factor de Transcripción Brn-3B/genética , Animales , Peso Corporal/genética , Inmunoprecipitación de Cromatina , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Ácido Glucárico/farmacología , Intolerancia a la Glucosa/genética , Prueba de Tolerancia a la Glucosa , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Proteínas de Homeodominio/efectos de los fármacos , Proteínas de Homeodominio/metabolismo , Immunoblotting , Insulina/farmacología , Ratones , Ratones Noqueados , Fibras Musculares Esqueléticas/efectos de los fármacos , Mutación , ARN Mensajero/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción Brn-3B/efectos de los fármacos , Factor de Transcripción Brn-3B/metabolismoRESUMEN
BACKGROUND: There is a significant clinical need for effective treatment of iron deficiency. A number of compounds that can be administered intravenously have been developed. This study examines how the compounds are handled by macrophages and their relative potential to provoke oxidative stress. METHODS: Human kidney (HK-2) cells, rat peritoneal macrophages and renal cortical homogenates were exposed to pharmaceutical iron preparations. Analyses were performed for indices of oxidative stress and cell integrity. In addition, in macrophages, iron uptake and release and cytokine secretion was monitored. RESULTS: HK-2 cell viability was decreased by iron isomaltoside and ferumoxytol and all compounds induced lipid peroxidation. In the renal cortical homogenates, lipid peroxidation occurred at lowest concentrations with ferric carboxymaltose, iron dextran, iron sucrose and sodium ferric gluconate. In the macrophages, iron sucrose caused loss of cell viability. Iron uptake was highest for ferumoxytol and iron isomaltoside and lowest for iron sucrose and sodium ferric gluconate. Iron was released as secretion of ferritin or as ferrous iron via ferroportin. The latter was blocked by hepcidin. Exposure to ferric carboxymaltose and iron dextran resulted in release of tumor necrosis factor α. CONCLUSIONS: Exposure to iron compounds increased cell stress but was tissue and dose dependent. There was a clear difference in the handling of iron from the different compounds by macrophages that suggests in vivo responses may differ.
Asunto(s)
Disacáridos/farmacología , Células Epiteliales/efectos de los fármacos , Compuestos Férricos/farmacología , Óxido Ferrosoférrico/farmacología , Hierro/metabolismo , Macrófagos Peritoneales/efectos de los fármacos , Animales , Proteínas de Transporte de Catión/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/metabolismo , Sacarato de Óxido Férrico , Ferritinas/metabolismo , Ácido Glucárico/farmacología , Hepcidinas/metabolismo , Humanos , Complejo Hierro-Dextran/farmacología , Riñón/citología , Riñón/efectos de los fármacos , Riñón/metabolismo , Peroxidación de Lípido , Macrófagos Peritoneales/citología , Macrófagos Peritoneales/metabolismo , Maltosa/análogos & derivados , Maltosa/farmacología , Estrés Oxidativo , Cultivo Primario de Células , Ratas , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Triple recycling (i.e., enterohepatic, enteric and local recycling) plays a central role in governing the disposition of phenolics such as flavonoids, resulting in low systemic bioavailability but higher gut bioavailability and longer than expected apparent half-life. The present study aims to investigate the coexistence of these recycling schemes using model bioactive flavonoid tilianin and a four-site perfused rat intestinal model in the presence or absence of a lactase phlorizin hydrolase (LPH) inhibitor gluconolactone and/or a glucuronidase inhibitor saccharolactone. The result showed that tilianin could be metabolized into tilianin glucuronide, acacetin, and acacetin glucuronide, which are excreted into the bile and luminal perfusate (highest in the duodenum and lowest in the colon). Gluconolactone (20 mM) significantly reduced the absorption of tilianin and the enteric and biliary excretion of acacetin glucuronide. Saccharolactone (0.1 mM) alone or in combination of gluconolactone also remarkably reduced the biliary and intestinal excretion of acacetin glucuronide. Acacetin glucuronides from bile or perfusate were rapidly hydrolyzed by bacterial ß-glucuronidases to acacetin, enabling enterohepatic and enteric recycling. Moreover, saccharolactone-sensitive tilianin disposition and glucuronide deconjugation, which was more active in the small intestine than the colon, points to the small intestinal origin of the deconjugation enzyme and supports the presence of local recycling scheme. In conclusion, our studies have demonstrated triple recycling of a bioactive phenolic (i.e., a model flavonoid), and this recycling may have an impact on the site and duration of polyphenols pharmacokinetics in vivo.
Asunto(s)
Flavonas/metabolismo , Flavonoides/farmacocinética , Glicósidos/farmacocinética , Mucosa Intestinal/metabolismo , Administración Oral , Animales , Bilis/metabolismo , Disponibilidad Biológica , Flavonoides/administración & dosificación , Ácido Glucárico/análogos & derivados , Ácido Glucárico/farmacología , Gluconatos/farmacología , Glucuronidasa/antagonistas & inhibidores , Glucuronidasa/metabolismo , Glucurónidos/metabolismo , Glicósidos/administración & dosificación , Semivida , Lactasa-Florizina Hidrolasa/antagonistas & inhibidores , Lactasa-Florizina Hidrolasa/metabolismo , Lactonas/farmacología , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Intravenous iron preparations, like iron sucrose (IS) and ferric carboxymaltose (FCM) differ in their physicochemical stability. Thus differences in storage and utilization can be expected and were investigated in a non-clinical study in liver parenchyma HepG2-cells and THP-1 macrophages as models for toxicological and pharmacological target cells. HepG2-cells incorporated significant amounts of IS, elevated the labile iron pool (LIP) and ferritin and stimulated iron release. HepG2-cells had lower basal cellular iron and ferritin content than THP-1 macrophages, which showed only marginal accumulation of IS and FCM. However, FCM increased the LIP up to twofold and significantly elevated ferritin within 24 h in HepG2-cells. IS and FCM were non-toxic for HepG2-cells and THP-1 macrophages were more sensitive to FCM compared to IS at all concentrations tested. In a cell-free environment redox-active iron was higher with IS than FCM. Biostability testing via assessment of direct transfer to serum transferrin did not reflect the chemical stability of the complexes (i.e., FCM > IS). Effect of vitamin C on mobilisation to transferrin was an increase with IS and interestingly a decrease with FCM. In conclusion, FCM has low bioavailability for liver parenchyma cells, therefore liver iron deposition is unlikely. Ascorbic acid reduces transferrin-chelatable iron from ferric carboxymaltose, thus effects on hepcidin expression should be investigated in clinical studies.
Asunto(s)
Compuestos Férricos/farmacología , Ácido Glucárico/farmacología , Maltosa/análogos & derivados , Ácido Ascórbico/metabolismo , Línea Celular , Sacarato de Óxido Férrico , Ferritinas/metabolismo , Células Hep G2 , Humanos , Hierro/metabolismo , Hígado/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Maltosa/farmacologíaRESUMEN
We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development.
Asunto(s)
9,10-Dimetil-1,2-benzantraceno/toxicidad , Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Productos Biológicos/farmacología , Carcinogénesis/efectos de los fármacos , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/prevención & control , Animales , Factor Apoptótico 1 Activador de Proteasas/genética , Factor Apoptótico 1 Activador de Proteasas/metabolismo , Ácido Butírico/farmacología , Caspasas/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Citocromos c1/metabolismo , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Interacciones Farmacológicas , Activación Enzimática/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ácido Glucárico/farmacología , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Niacinamida/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Identification of the bioactive ingredient from traditional Chinese medicine (TCM) remains a challenging task by traditional approach that focuses on chemical isolation coupled with biological activity screening. Here, we present a metabonomics-based approach for bioactive ingredient discovery in LiuWeiDiHuang pills (LWPs). First, a non-targeted high-performance liquid chromatography ultraviolet (HPLC-UV) profiling of rat urine was used to discriminate urinary profiling intervened by LWPs. Orthogonal partial least-squares discriminant analysis (OPLS-DA) revealed that eight chromatographic peaks made a significant contribution to the classification of the LWPs group and the control group. Five of these chromatographic peaks were successfully isolated and identified as hippurate, genistein (GT), daidzein (DZ), and glucuronide conjugate of GT and that of DZ by mass spectroscopy (MS). Subsequently, we found that LWPs significantly decreased the activity of intestinal ß-glucuronidase by 18 % and exerted a dose-dependent inhibitory effect on rat liver lysosomal fraction, suggesting that LWPs were a ß-glucuronidase inhibitor. In the end, by inhibiting ß-glucuronidase-guided isolation, D-glucaro-1,4-lactone, a previously unreported ingredient of LWPs, was identified by MS, MS/MS, and nuclear magnetic resonance spectroscopy. Our findings indicated that metabonomics might increase research productivity toward the drug targets and/or bioactive compounds from TCM.
Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Ácido Glucárico/análogos & derivados , Glucuronidasa/antagonistas & inhibidores , Metabolómica/métodos , Animales , Biomarcadores/análisis , Cromatografía Líquida de Alta Presión/métodos , Análisis Discriminante , Medicamentos Herbarios Chinos/análisis , Inhibidores Enzimáticos/análisis , Inhibidores Enzimáticos/farmacología , Ácido Glucárico/análisis , Ácido Glucárico/farmacología , Análisis de los Mínimos Cuadrados , Espectroscopía de Resonancia Magnética , Masculino , Ratas Sprague-Dawley , Urinálisis/métodosRESUMEN
D-Glucaro-1,4-lactone (1,4-GL) has been shown to have a hypocholesterolemic effect in rats and human subjects. However, little information is known concerning the alteration of metabolome associated with the effect. Here, we show that 1,4-GL delays the development of hypercholesterolemia with the coadministration of a high-fat, high-cholesterol diet (HFHC) in rats. Metabonomic results based on proton nuclear magnetic resonance indicate that urinary trimethylamine N-oxide, trimethylamine, lactate, acetate, formate, and creatinine are significantly altered after 1,4-GL and HFHC treatments. Colonic flora test results reveal that the quantity of Bifidobacterium and Lactobacillus in the intestines respectively increase by about 1.7- and 4.2-fold in rats treated with 1,4-GL compared with those in the control group. Rats that were coadministered with HFHC and 1,4-GL exhibit normal levels of lactate and acetate in serum and display urinary excretions of lactate and acetate that are 2 to 3 times higher compared with those treated with HFHC alone. The results imply that the increased probiotic quantities and urinary excretion of breakdown products of fat/cholesterol after 1,4-GL treatment contribute to the prevention of hypercholesterolemia. Our study offers insights into the model of action for 1,4-GL in preventing hypercholesterolemia.
Asunto(s)
Tracto Gastrointestinal/microbiología , Ácido Glucárico/análogos & derivados , Hipercolesterolemia/prevención & control , Metaboloma/efectos de los fármacos , Animales , Bifidobacterium , Colesterol en la Dieta/administración & dosificación , Colesterol en la Dieta/efectos adversos , Creatinina/orina , Dieta Alta en Grasa/efectos adversos , Femenino , Ácido Glucárico/farmacología , Hipercolesterolemia/sangre , Lactobacillus , Hígado/efectos de los fármacos , Hígado/metabolismo , Metilaminas , Probióticos/administración & dosificación , Ratas , Ratas Sprague-Dawley , Triglicéridos/sangreRESUMEN
High-dose intravenous iron supplementation is associated with adverse cardiovascular outcomes in patients with CKD, but the underlying mechanism is unknown. Our study investigated the causative role of iron sucrose in leukocyte-endothelium interactions, an index of early atherogenesis, and subsequent atherosclerosis in the mouse remnant kidney model. We found that expression levels of intracellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and adhesion of U937 cells increased in iron-treated human aortic endothelial cells through upregulated NADPH oxidase (NOx) and NF-κB signaling. We then measured mononuclear-endothelial adhesion and atherosclerotic lesions of the proximal aorta in male C57BL/6 mice with subtotal nephrectomy, male apolipoprotein E-deficient (ApoE(-/-)) mice with uninephrectomy, and sham-operated mice subjected to saline or parenteral iron loading. Iron sucrose significantly increased tissue superoxide production, expression of tissue cell adhesion molecules, and endothelial adhesiveness in mice with subtotal nephrectomy. Moreover, iron sucrose exacerbated atherosclerosis in the aorta of ApoE(-/-) mice with uninephrectomy. In patients with CKD, intravenous iron sucrose increased circulating mononuclear superoxide production, expression of soluble adhesion molecules, and mononuclear-endothelial adhesion compared with healthy subjects or untreated patients. In summary, iron sucrose aggravated endothelial dysfunction through NOx/NF-κB/CAM signaling, increased mononuclear-endothelial adhesion, and exacerbated atherosclerosis in mice with remnant kidneys. These results suggest a novel causative role for therapeutic iron in cardiovascular complications in patients with CKD.
Asunto(s)
Aterosclerosis/metabolismo , Compuestos Férricos/metabolismo , Ácido Glucárico/metabolismo , Insuficiencia Renal Crónica/metabolismo , Superóxidos/metabolismo , Animales , Aterosclerosis/inducido químicamente , Aterosclerosis/patología , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Células Endoteliales/citología , Compuestos Férricos/farmacología , Sacarato de Óxido Férrico , Ácido Glucárico/farmacología , Humanos , Inyecciones Intravenosas , Molécula 1 de Adhesión Intercelular/metabolismo , Leucocitos/citología , Leucocitos/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/fisiología , Masculino , Ratones Endogámicos C57BL , Monocitos/citología , Monocitos/metabolismo , FN-kappa B/metabolismo , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/patología , Células U937 , Regulación hacia Arriba/fisiología , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
BACKGROUND: Kombucha tea (KT), a traditional health beverage containing potential hepatoprotective agents, is fermented from sugared tea by a symbiotic culture of yeast and bacteria for 8 days. However, the functional strains that produce components for the hepatoprotective property of KT remain unclear. Multiple strains are involved in traditional KT production. Therefore, KT has not been standardized or produced commercially. This study aimed to identify the functional strains and quantify the functional components with hepatoprotective effects in kombucha tea. RESULTS: Gluconacetobacter sp. A4 was one of the microorganisms in KT in which the D-saccharic acid-1,4-lactone (DSL) produced by G. sp. A4 was significantly higher than that produced by original tea fungus at 8 days of fermentation. Traditional KT (TKT, tea broth fermented by mixed tea fungus), modified KT (MKT, fermented by single G. sp. A4), and DSL significantly inhibited the acetaminophen-induced increase of alanine aminotransferase, alkaline phosphatase, triglyceride and malondialdehyde, as well as facilitating the reduction of total antioxidant capacity in mice. Furthermore, MKT and TKT are both similar to DSL in terms of protection against acetaminophen-induced liver injury in mice. These results suggested a positive relationship between DSL content and the hepatoprotective effect of TKT, MKT and DSL groups. CONCLUSION: G. sp. A4 was concluded to be a potential functional strain and DSL might be the key functional component for the hepatoprotective property in KT. The stronger capability of G. sp. A4 in producing DSL makes it a better choice for the commercial production of KT.
Asunto(s)
Camellia sinensis/química , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Ácido Glucárico/uso terapéutico , Gluconacetobacter , Lactonas/uso terapéutico , Hígado/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Té/microbiología , Acetaminofén , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Bebidas , Camellia sinensis/microbiología , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Fermentación , Ácido Glucárico/farmacología , Lactonas/farmacología , Hígado/enzimología , Masculino , Malondialdehído/sangre , Ratones , Ratones Endogámicos ICR , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Triglicéridos/sangre , LevadurasRESUMEN
Hepcidin, which is mainly produced by the liver, is the key regulator in iron homeostasis. Hepcidin expression is up-regulated by iron loading in vivo, but the mechanism underlying this process is not completely understood. In the present study, we investigated the mechanism, following the hypothesis that hepcidin production in response to iron loading is regulated by extra-hepatic iron sensors. We measured serum hepcidin concentrations and iron indices in Wistar rats treated with saccharated ferric oxide (SFO). Human hepatoma-derived HepG2 cells were stimulated using SFO-administered rat sera, and co-cultured with rat spleen cells, human monocyte-derived THP-1 cells, or human monocytes with diferric transferrin (holo-Tf), and hepcidin concentrations in the conditioned media were measured. SFO elevated rat serum hepcidin concentrations. SFO-treated rat sera increased hepcidin production from HepG2 cells, and this induction correlated with serum hepcidin levels, but not with iron indices. Holo-Tf up-regulated hepcidin concentrations in media from HepG2 cells co-cultured with rat spleen cells, THP-1 cells, or human monocytes with or without cell-to-cell contacts, while holo-Tf did not up-regulate hepcidin from HepG2 cells alone. Our results suggest the existence of humoral factors capable of inducing hepcidin production that are secreted by extra-hepatic cells, such as reticuloendothelial monocytes, in response to iron.