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1.
Scand J Rheumatol ; 48(5): 383-392, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31354003

RESUMEN

Objectives: The discovery of alternative and well-tolerated anti-arthritic drugs, especially from natural products, is becoming an area of active research. Pedunculoside (PE) is a novel triterpene saponin extracted from the dried bark of Ilex rotunda Thunb. Limited published papers have reported its pharmacological properties, including anti-inflammatory, anti-myocardial ischaemia, anti-liver injury, and hypocholesterolaemic activities. However, the effect of PE on rheumatoid arthritis (RA) remains unknown. Here, we investigated the anti-arthritic effect of PE in both in vitro and in vivo models. Method: The inhibitory effects of PE on proliferation, migration, and production of inflammatory mediators in primary fibroblast-like synoviocytes (FLSs) were examined by a 5-ethynyl-2'-deoxyuridine incorporation assay, wound-healing assay, and real-time polymerase chain reaction, respectively. Cellular signalling mechanisms were analysed by Western blot. The in vivo studies were performed using a collagen-induced arthritis (CIA) rat model. Multiple methods, including arthritis scoring, enzyme-linked immunoassay, radiography, and histopathological assessment, were used to evaluate the therapeutic effects of PE on CIA rats. Results: The in vitro studies revealed that PE significantly inhibited proliferation and migration of FLSs. PE also decreased the production of pro-inflammatory cytokines, including interleukin-1ß (IL-1ß), IL-6, IL-8, and tumour necrosis factor-α (TNF-α). Western blot results suggested that PE suppressed TNF-α-stimulated activation of p38 and extracellular signal-regulated kinase. The in vivo studies showed that PE treatment significantly inhibited synovial inflammation and bone destruction in CIA rats. Conclusion: These results demonstrate that PE exerts an inhibitory role in FLSs and CIA rats, and therefore may have therapeutic value for the treatment of RA.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Glucosa/análogos & derivados , Membrana Sinovial/patología , Triterpenos/farmacología , Animales , Artritis Experimental/diagnóstico , Artritis Experimental/metabolismo , Proliferación Celular , Células Cultivadas , Citocinas/metabolismo , Desoxicitidina/metabolismo , Medicamentos Herbarios Chinos , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Citometría de Flujo , Glucosa/farmacología , Fenotipo , Radiografía , Ratas , Ratas Wistar , Membrana Sinovial/metabolismo
2.
J Neuroendocrinol ; 29(5)2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28295740

RESUMEN

To study the mechanism by which monochromatic light affects gonadotrophin-releasing hormone (GnRH) expression in chicken hypothalamus, a total of 192 newly-hatched chicks were divided into intact, sham-operated and pinealectomy groups and exposed to white (WL), red (RL), green (GL) and blue (BL) lights using a light-emitting diode system for 2 weeks. In the GL intact group, the mRNA and protein levels of GnRH-I in the hypothalamus, the mean cell area and mean cell optical density (OD) of GnRH-I-immunoreactive (-ir) cells of the nucleus commissurae pallii were decreased by 13.2%-34.5%, 5.7%-39.1% and 9.9%-17.3% compared to those in the chicks exposed to the WL, RL and BL, respectively. GL decreased these factors related to GnRH-I expression and the effect of GL was not observed in pinealectomised birds. However, the mRNA and protein levels of hypothalamic gonadotrophin-inhibitory hormone (GnIH) and GnIH receptor (GnIHR), the mean cell area and mean cell OD of the GnIH-ir cells of the paraventricularis magnocellularis, and the plasma melatonin concentration in the chicks exposed to GL were increased by 18.6%-49.2%, 21.1%-60.0% and 8.6%-30.6% compared to the WL, RL and BL intact groups, respectively. The plasma melatonin concentration showed a negative correlation with GnRH-I protein and a positive correlation with GnIH and GnIHR proteins. Protein expression of both GnRH-I and GnIHR showed a negative correlation in the hypothalamus. After pinealectomy, GnRH-I expression increased, whereas plasma melatonin concentration, GnIH and GnIHR expression decreased, and there were no significant differences among the WL, RL, GL and BL groups. Double-labelled immunofluorescence showed that GnIH axon terminals were near GnRH-I neurones, some GnRH-I neurones coexpressed with GnIHR and GnIH neurones coexpressed with melatonin receptor subtype quinone reductase 2. These results demonstrate that green light inhibits GnRH-I expression by increasing melatonin secretion and stimulating melatonin receptor-GnIH-GnIH receptor pathway in the chick brain.


Asunto(s)
Proteínas Aviares/metabolismo , Hormonas Hipotalámicas/metabolismo , Hipotálamo/metabolismo , Melatonina/metabolismo , Animales , Pollos , Luz , Masculino , Melatonina/sangre , Fibras Nerviosas/metabolismo , Neuronas/metabolismo , Transducción de Señal/fisiología
3.
Schizophr Res ; 189: 175-180, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28236519

RESUMEN

Schizophrenia is a prototypical disorder of brain connectivity with altered neural activity in regions extending throughout the brain. Regions, including the subcortex and cortex, present activity mainly within a specific frequency band in resting-state. Whether these altered resting-state functional connections also present frequency specificity is unknown. In the present study, empirical mode decomposition, which is a pure data-driven method suitable for nonlinear and nonstationary signals, was used to decompose blood-oxygen-level-dependent (BOLD) signals into different intrinsic frequency bands. Our study included 42 first-episode drug-naive patients with schizophrenia and 38 controls. Significant aberration in functional connectivity was observed only at a higher frequency range (the peak spectral density power was 0.06Hz). In this frequency band, patients with schizophrenia showed significantly increased functional connections between the bilateral cuneus and right supplementary motor area, reduced connections within the basal ganglia, and reduced connections between the dorsal striatum and left supplementary motor area. The dysfunction of the frontal gyrus significantly correlated with the dysfunction of the basal ganglia. Notably, these altered connections were significantly correlated with symptom severity. Our results demonstrate that frequency-selective altered corticostriatal-thalamo-cortical circuits in patients with schizophrenia are associated with symptoms severity.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Cuerpo Estriado/diagnóstico por imagen , Vías Nerviosas/diagnóstico por imagen , Descanso , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Adulto , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Oxígeno/sangre , Esquizofrenia/patología , Adulto Joven
4.
Vitam Horm ; 101: 257-310, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27125746

RESUMEN

Alpha-Klotho (αKlotho) protein is encoded by the gene, Klotho, and functions as a coreceptor for endocrine fibroblast growth factor-23. The extracellular domain of αKlotho is cleaved by secretases and released into the circulation where it is called soluble αKlotho. Soluble αKlotho in the circulation starts to decline in chronic kidney disease (CKD) stage 2 and urinary αKlotho in even earlier CKD stage 1. Therefore soluble αKlotho is an early and sensitive marker of decline in kidney function. Preclinical data from numerous animal experiments support αKlotho deficiency as a pathogenic factor for CKD progression and extrarenal CKD complications including cardiac and vascular disease, hyperparathyroidism, and disturbed mineral metabolism. αKlotho deficiency induces cell senescence and renders cells susceptible to apoptosis induced by a variety of cellular insults including oxidative stress. αKlotho deficiency also leads to defective autophagy and angiogenesis and promotes fibrosis in the kidney and heart. Most importantly, prevention of αKlotho decline, upregulation of endogenous αKlotho production, or direct supplementation of soluble αKlotho are all associated with attenuation of renal fibrosis, retardation of CKD progression, improvement of mineral metabolism, amelioration of cardiac function and morphometry, and alleviation of vascular calcification in CKD. Therefore in rodents, αKlotho is not only a diagnostic and prognostic marker for CKD but the enhancement of endogenous or supplement of exogenous αKlotho are promising therapeutic strategies to prevent, retard, and decrease the comorbidity burden of CKD.


Asunto(s)
Glucuronidasa/fisiología , Insuficiencia Renal Crónica , Animales , Biomarcadores , Enfermedades Cardiovasculares , Epigénesis Genética , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos , Regulación de la Expresión Génica , Glucuronidasa/deficiencia , Glucuronidasa/genética , Humanos , Riñón/metabolismo , Proteínas Klotho , Minerales/metabolismo , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/fisiopatología
5.
Free Radic Res ; 48(9): 1049-60, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24797165

RESUMEN

Male C57BL/6J mice treated with D-galactose (DG) were used to examine the effects of ergothioneine (EGT), melatonin (MEL), or their combination (EGT+MEL) on learning and memory abilities. The mice were divided into five groups and injected subcutaneously with DG (0.3 mL of 1% DG/mouse) except for group 1 (normal controls). Group 3 was orally supplemented with EGT [0.5 mg/kg body weight (bw)], group 4 with MEL (10 mg/kg bw, p.o.), and group 5 with EGT+MEL. EGT and MEL were provided daily for 88 days, while DG was provided between days 7 to 56. Active avoidance task and Morris water-maze task were used to evaluate learning and memory abilities. DG treatment markedly increased escape latency and decreased the number of avoidance in the active avoidance test, whereas EGT and MEL alone significantly improved the performance. DG also impaired the learning and memory abilities in the water-maze task, and EGT and MEL alone also significantly improved the performance. EGT+MEL produced the strongest effects in both tasks. EGT and MEL alone markedly decreased ß-amyloid protein accumulation in the hippocampus and significantly inhibited lipid peroxidation and maintained glutathione/glutathione disulfide ratio and superoxide dismutase activity in brain tissues of DG-treated mice. MEL alone completely prevented the rise in brain acetylcholine esterase activity induced by DG, whereas EGT and EGT+MEL were only partially effective. Overall, EGT, MEL, and, in particular, the combination of EGT and MEL effectively protect against learning and memory deficits in C57BL/6J mice treated with DG, possibly through attenuation of oxidative damage.


Asunto(s)
Antioxidantes/farmacología , Encéfalo/efectos de los fármacos , Ergotioneína/farmacología , Melatonina/farmacología , Enfermedad de Alzheimer/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Galactosa/toxicidad , Inmunohistoquímica , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Trastornos de la Memoria/inducido químicamente , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos
6.
Curr Pharm Biotechnol ; 14(13): 1088-92, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24725126

RESUMEN

A 46-year-old female underwent surgery for cancer of the right breast mammary (T3N2M0) in Sep 2010. Following post surgery, adjuvant chemotherapy of CAF regimens (cyclophosphamide+adriamycin+fluorouracil) was administered. Two years later, multiple pulmonary and skeletal metastatic lesions had been found by CT (computerized tomography) and ECT (emission computed tomograph) imaging. She received the treatment of second-line chemotherapy regimens of GP (cisplatin + gemcitabine). In the meantime, we administered Chinese traditional herb drugs (Fei Decoction, mixed a variety of effective herbal components) to help her recover from the poor condition. After taking the Chinese herbs for 2 months, the tumour marker (CEA, CA15-3) dramatically decreased, resulting in the normal range. Both lung and bone metastatic sites reduced according to CT and ECT imaging, and the patient felt free from the complaint of pulmonary and cardiac discomfort. Over time, the quality of life has been greatly improved, we have managed to prolong the PFS (progression-free-survival) and TTP (time-to-progression) from the onset to date. CTM (Chinese traditional medicine) considers human body as a dynamic platform in which all organs are correlative and bind each other. Relationship between heart, liver, spleen, lung and kidney is like an interlink between mother and son, and runs in cycle as a circle. In the course of this combined treatment, we showed that Chinese herbal medicine played an important role in the therapy of breast cancer. Chinese herbs might be an additional choice with their better benefits and tolerability in the treatment of recurrent breast cancer.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico por imagen , Terapia Combinada , Ciclofosfamida , Supervivencia sin Enfermedad , Femenino , Fluorouracilo , Humanos , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
7.
Tissue Cell ; 46(1): 103-11, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24411713

RESUMEN

Layer 10 neurons of the chick tectum were morphologically investigated. The layer 10 neurons displayed heterogeneous immunoreactivities to calcium-binding proteins (CaBPs). Calbindin (CB)-immunoreactive (ir) neurons had pyramidal or round somata, primarily found in layers 5, 9, and 13. Parvalbumin (PV)-ir neurons were of various shapes with small to large somata (109.7±48.6µm(2)) that were located mainly in layers 4 and 10. Calretinin (CR)-ir neurons had small to middle-sized somata (79.3±9.7µm(2)) located primarily in layers 10 and 13, and most of them were similar to typical radial cells in size and shape. Two distinct types of neurons that projected to the nucleus geniculatus lateralis, pars ventralis (GLv) and ventral thalamus were demonstrated in layer 10. Type 1 cells had small to middle-sized somata (74.3±33µm(2)), and each cell had a single apical dendrite that ramified into bush-like branches in layer 7. These cells corresponded to CR-ir neurons and radial cells in size and shape. Type 2 cells had larger somata (124.7±52.6µm(2)), and their shapes were pyramidal, polygonal, or oval. They had multiple obliquely ascending dendrites that ramified into bush-like branches in layer 7. These cells often appeared similar to PV-ir neurons.


Asunto(s)
Forma de la Célula , Neuronas/citología , Parvalbúminas/metabolismo , Tálamo/citología , Vías Visuales/anatomía & histología , Animales , Calbindinas/metabolismo , Pollos , Proteínas del Tejido Nervioso/metabolismo , Vías Visuales/fisiología , Cigoto
8.
Curr Pharm Biotechnol ; 13(9): 1718-30, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22039823

RESUMEN

Herbal supplements are often used concomitantly with conventional medications resulting in considerable potential for herb-drug interactions. These interactions, which are generally through interfering with pharmacokinetic and/or pharmacodynamic pathways, may result in beneficial effects or more often adverse reactions such as toxicity or treatment failure and may be influenced by multiple environmental and/or genetic factors. The pharmacogenetic approach may help to identify some interactions which may be more pronounced or only occur in specific groups of subjects although the complex nature of the herbal medicines may limit the discovery of such an interaction. Preclinical studies such as gene expression profiling in rodent liver may help to define metabolic pathways influenced by herbal medicines and facilitate more accurate targeting of human in vivo studies. This review discusses the mechanisms of herb-drugs interaction and the potential influence of genetic variation on herb-drug interactions based on available clinical evidence.


Asunto(s)
Transporte Biológico/genética , Enzimas/genética , Interacciones de Hierba-Droga/genética , Inactivación Metabólica/genética , Animales , Enzimas/metabolismo , Variación Genética , Medicina de Hierbas/métodos , Humanos
9.
Waste Manag ; 29(12): 3029-35, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19747813

RESUMEN

The effects of temperature on the release of chemical components of six solid organic materials under conditions of oversaturation were investigated in this paper. The six materials were peat moss (PM), weathered coals (WC), charred rice husks (CRH), sawdust (Sd), turfgrass clippings (TC), and chicken manure (CM). Significant differences were observed in the available nitrogen and phosphorus content of the aqueous extracts of organic materials at different temperatures. The available nitrogen content in aqueous extracts of PM and WC at 25 degrees C was higher than that registered at 15 degrees C and 35 degrees C. Available nitrogen content in the aqueous extracts of CRH, Sd, TC, and WC at 35 degrees C was higher than at 15 degrees C and 25 degrees C. The available phosphorus content in the aqueous extracts of organic materials at 35 degrees C was higher than that available at 15 degrees C and 25 degrees C, with the exception of Sd. In addition, the release of available phosphorus in the aqueous solution of organic materials at different temperatures varied constantly for 108h. The release of potassium (K(+)) and sodium (Na(+)) ions in the aqueous extracts of organic materials was basically steady over time, with the exception of CM. High temperature (35 degrees C) may significantly hasten the release of K(+) from organic substrates (except for WC) with low temperatures significantly inhibiting release of K(+) in Sd and CRH. High temperatures (35 degrees C) might significantly facilitate the release of Na(+) in CM and TC. However, no significant differences were manifested in the release of Na(+) from organic substrates at different temperatures, with the exception of CM and TC. Moreover, no significant differences were observed in the release of calcium, magnesium and iron ions with time, nor were there any significant differences in the contents of iron ions in the aqueous extracts of organic materials at different temperatures. The results indicate that multiple mediums should be pretreated in water for a week before being used for planting. They should be used when all mineral elements of organic materials are steady and ignoring the effect of organic mediums.


Asunto(s)
Agricultura/métodos , Temperatura , Residuos/análisis , Agua/química , Elementos Químicos , Metales/análisis , Nitrógeno/análisis , Fósforo/análisis
10.
Pain Physician ; 8(3): 315-8, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16850089

RESUMEN

BACKGROUND: Meralgia paresthetica is a clinical syndrome of pain, dysesthesia or both, in the anterolateral thigh. It is associated with an entrapment mononeuropathy of the lateral femoral cutaneous nerve. Diagnosis of meralgia paresthetica is typically made clinically and is based on the characteristic location of pain or dysesthesia, sensory abnormality on exam, and absence of any other neurological abnormality in the leg. The majority of patients with meralgia paresthetica respond well to conservative treatment. OBJECTIVE: To present a case of intractable meralgia paresthetica in which conservative treatment options failed but which was successfully treated with a spinal cord stimulator. CASE REPORT: A 44-year-old woman presented to the pain clinic with a one-year history of bilateral anterolateral thigh pain. History, physical exam, and diagnostic work-up were consistent with meralgia paresthetica. Multiple medications, physical therapy, and chiropractic therapy were not successful for this patient. In addition, local anesthetic/steroid injection of the lateral femoral cutaneous nerve provided only short-term relief. Ultimately, a spinal cord stimulator was implanted after a successful temporary percutaneous trial. Two months after the implantation, she continued to have 100% pain relief, worked full-time, was physically active, and no longer required any pain medication including opioids. CONCLUSION: An implanted spinal cord stimulator may be an ideal treatment for intractable meralgia paresthetica after conservative treatments have failed because it is not destructive and can always be explanted without significant permanent adverse effects.

11.
Free Radic Res ; 35(2): 203-13, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11697201

RESUMEN

Two recent clinical trials suggest that beta-carotene may be harmful to smokers. In this study we examined the hypothesis that beta-carotene may become toxic when degradation occurs. beta-Carotene (BC) and lycopene (LP) with or without prior heat treatment (60 degrees C for 1 h in open air) were incubated at 20 and 40 microM with calf thymus DNA or human fibroblasts Hs68 cells. The heat treatment resulted in ca. 80% and 35% bleaching of BC and LP, respectively. When Hs68 cells were incubated with the oxidized beta-carotene (OBC) or oxidized lycopene (OLP) at 37 degrees C for 20 h, cell viability was significantly and dose-dependently decreased whereas cell viability was not affected by BC or LP. Cell death, which was already evident at 4 h after incubation with OBC or OLP, was possibly attributable to apoptosis, as shown by the increased histone-associated DNA fragmentation. However, cell lysis, measured as release of lactate dehydrogenase, also occurred at 4 h after incubation with OBC and OLP, although the extent was relatively small and was greater for OLP than for OBC. When calf thymus DNA was incubated with OBC or OLP at 37 degrees C for 20 h, the 8-hydroxy-2-deoxyguanosine (8-OH-dG) level was significantly and dose-dependently increased by OLP whereas the increase by OBC was only significant at 40 microM. When Hs68 cells were incubated with OBC and OLP for 20 h, both compounds increased the 8-OH-dG level, but the effect was only significant for 40 microM OLP. Comet (single-cell gel electrophoresis) assay of DNA damage in Hs68 cells was determined at 2 h after incubation with OBC or OLP because of its high sensitivity. Both OBC and OLP significantly and dose-dependently increased DNA breakage while BC and LP had no effect. Inclusion of BHT during incubation of cells with 40 microM OBC or OLP partially inhibited (ca. 40%, p < .05) the extent of comet formation. Intriguingly, OBC and OLP neither induce lipid peroxidation in Hs68 cells (measured as thiobarbituric acid-reactive substances released into the medium) nor increased the intracellular level of reactive oxygen species. Although it is presently unclear about what degradation products are formed, this study has demonstrated that, when oxidized, BC and LP lead to oxidative damage to both purified DNA and cellular DNA. The results suggest that such damage may contribute to the adverse effects of beta-carotene reported in recent clinical studies and caution that it is important to prevent oxidation of BC and LP for human uses such as in supplemental studies.


Asunto(s)
Carotenoides/farmacología , Daño del ADN/efectos de los fármacos , Desoxiguanosina/análogos & derivados , beta Caroteno/análogos & derivados , beta Caroteno/farmacología , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Bovinos , Línea Celular , Supervivencia Celular/efectos de los fármacos , ADN/metabolismo , Desoxiguanosina/metabolismo , Electroforesis en Gel de Agar , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Histonas/metabolismo , Humanos , Peroxidación de Lípido/efectos de los fármacos , Licopeno , Masculino , Oxidación-Reducción/efectos de los fármacos , Factores de Tiempo , beta Caroteno/metabolismo
12.
Eur J Pharm Sci ; 12(1): 63-8, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11121734

RESUMEN

Human CYP3A4, the major human, intestinal, drug metabolizing cytochrome P450, has been introduced into three mammalian cell lines (Caco-2, MDCK and LLC-PK1) suitable for making drug permeability measurements. The levels and stability of expression were analyzed by enzyme assays (testosterone 6beta-hydroxylase and nifedipine oxidase). Long term, stable CYP3A4 expression/cell growth rate was obtained in MDCK cells. In the LLC-PK1 system, shorter term, stable expression was achieved. However, in Caco-2 cells, derivatives with better properties than those previously reported could not be obtained. The highest level of CYP3A4 catalytic activity was obtained in LLC-PK1 cells. In this system, CYP3A4 activity levels appeared comparable to median level human intestinal microsomes. Metabolite formation and inhibition kinetics were examined in cell monolayers. Nifedipine was found to be extensively metabolized (19%) during passage across cell monolayers. In general, affinity related parameters (apparent Km and apparent Ki) were 1.5- to three-fold higher under conditions of flux through the monolayers relative to steady-state conditions. These systems should be useful for examining the role of intestinal CYP3A4 in first-pass metabolism and drug-drug interactions.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Oxigenasas de Función Mixta/metabolismo , Preparaciones Farmacéuticas/metabolismo , Animales , Atenolol/metabolismo , Transporte Biológico , Línea Celular , Permeabilidad de la Membrana Celular , Cimetidina/metabolismo , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/genética , ADN Complementario , Eritromicina/metabolismo , Glucosa/metabolismo , Humanos , Mamíferos , Manitol/metabolismo , Oxigenasas de Función Mixta/genética , Fenilalanina/metabolismo , Propranolol/metabolismo , Proteínas Recombinantes/metabolismo , Testosterona/metabolismo , Células Tumorales Cultivadas , Verapamilo/metabolismo
13.
J Steroid Biochem Mol Biol ; 75(2-3): 159-66, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11226832

RESUMEN

Dehydroepiandrosterone (DHEA), a major steroid secreted by the adrenal gland which decreases with age after adolescence, is available as a nutritional supplement. DHEA is known to have antiproliferative effects but the mechanism is unclear. In this study using BV-2 cells, a murine microglial cell line, we investigated the effect of DHEA on cell viability and the interaction between DHEA and glucose concentrations in the medium. We showed that DHEA inhibited cell viability and G6PD activity in a dose-dependent manner and that the effect of DHEA on cell viability was inversely associated with glucose concentrations in the medium, i.e. lowered glucose strongly enhanced the inhibition of cell viability by DHEA. DHEA inhibited cell growth by causing cell cycle arrest primarily in the G0--G1 phase, and the effect was more pronounced at zero glucose (no glucose added, G0) than high glucose (4.5 mg/ml of the medium, G4.5). Glucose deprivation also enhanced apoptosis induced by DHEA. At G4.5, DHEA did not induce formation of DNA ladder until it reached 200 microM. However, at G0, 100 microM DHEA was able to induce apoptosis, as evidenced by the formation of DNA ladder, elevation of histone-associated DNA fragmentation and increase in cells positively stained with annexin V-FITC and annexin V-FITC/propidium iodide. The interactions between DHEA and glucose support the contention that DHEA exerts its antiproliferative effects through alteration of glucose metabolism, possibly by inhibition of G6PD activity leading to decreased supply of ribose-5-phosphate for synthesis of DNA and RNA. Although DHEA is only antiproliferative at pharmacological levels, our results indicate that its antiproliferative effect can be enhanced by limiting the supply of glucose such as by energy restriction. In addition, the present study shows that glucose concentration is an important factor to consider when studying the antiproliferative and toxicological effects of DHEA.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Deshidroepiandrosterona/farmacología , Glucosa/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Animales , Ciclo Celular/fisiología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Medios de Cultivo , Fragmentación del ADN , Relación Dosis-Respuesta a Droga , Glucosa/farmacología , Humanos , Ratones , Microglía/fisiología
14.
Diabetes Educ ; 25(2): 237-45, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10531849

RESUMEN

PURPOSE: The adsorption characteristics and stability profile of an insulin analog, lispro insulin, were evaluated against a recombinant human regular insulin using intravenous infusion sets and syringes. METHODS: Studies were performed using either 0.9% NaCl or 5% dextrose intravenous injection solution. Effects of container type, infusion rate, product concentration, presence-absence of an in-line filter, and storage condition on release profiles of lispro and human regular insulin infusion solutions were determined. RESULTS: Lispro insulin and m-cresol were chemically stable. Release rates of insulin (both types) were steady after an initial lag time. The lag time was much longer with intravenous bag infusion than with intravenous syringe infusion. A higher product concentration, faster flow rate, and prewash of the infusion tubing were shown to substantially decrease the lag time. CONCLUSIONS: The adsorption profile of lispro insulin was the same as that of human regular insulin in both syringes and bags. Use of a load-and-sit prewash scheme may shorten or nearly eliminate the lag time, which in turn may be used to make a more accurate calculation of a patient's dose.


Asunto(s)
Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacología , Infusiones Intravenosas/instrumentación , Insulina/análogos & derivados , Adsorción , Cresoles/administración & dosificación , Cresoles/farmacología , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Humanos , Insulina/administración & dosificación , Insulina/farmacología , Insulina Lispro , Factores de Tiempo
15.
Food Chem Toxicol ; 37(5): 503-8, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10456678

RESUMEN

This study examined the in vivo antioxidant and/or prooxidant effect of short-term dehydroepiandrosterone (DHEA) injection and the effect of dietary vitamin E. Male Sprague-Dawley rats (4 wk old) were fed vitamin E-deficient or vitamin E-adequate (30 mg DL-alpha-tocopheryl acetate/kg) diet for 4 weeks followed by intraperitoneal injection of DHEA for 1 week. The results showed that DHEA injection caused a dose-dependent decrease in body weight, and this effect was more pronounced in vitamin E-deficient rats. In contrast, DHEA injection significantly increased liver, kidney and adrenal weights. Hepatic vitamin E content was significantly lowered by vitamin E deficiency, which led to significantly increased ex vivo and iron-induced lipid peroxidation. DHEA injection did not affect hepatic vitamin E content but significantly decreased ex vivo and iron-induced lipid peroxidation in vitamin E-deficient rats. Hepatic total sulfhydryl (SH) groups and non-protein SH contents were not affected by vitamin E but were significantly increased by DHEA injection, which at 100 mg/kg was not more effective than at 50 mg/kg. Hepatic glutathione S-transferase (GST) activity was significantly decreased by DHEA, but vitamin E alleviated such a decrease. DHEA injection significantly increased hepatic glucose 6-phosphate dehydrogenase (G6PD) activity, and the effect was dose dependent in vitamin E-deficient rats. Thus, DHEA may compensate for vitamin E deficiency in vivo, and this effect is masked when dietary vitamin E is adequate. The antioxidant effect of DHEA is accompanied by decreased body weights, enlarged (fat-laden) tissues and altered activities of hepatic GST and G6PD.


Asunto(s)
Antioxidantes/farmacología , Deshidroepiandrosterona/toxicidad , Dieta , Deficiencia de Vitamina E/tratamiento farmacológico , Análisis de Varianza , Animales , Deshidroepiandrosterona/farmacología , Evaluación Preclínica de Medicamentos , Glucosafosfato Deshidrogenasa/efectos de los fármacos , Glutatión Transferasa/efectos de los fármacos , Inyecciones Intraperitoneales , Masculino , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Factores de Tiempo
16.
J Biol Chem ; 274(31): 21515-8, 1999 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-10419454

RESUMEN

We have identified a cDNA for pleckstrin 2 that is 39% identical and 65% homologous to the original pleckstrin. Like the original pleckstrin 1, this protein contains a pleckstrin homology (PH) domain at each end of the molecule as well as a DEP (Dishevelled, Egl-10, and pleckstrin) domain in the intervening sequence. A Northern blot probed with the full-length cDNA reveals that this homolog is ubiquitously expressed and is most abundant in the thymus, large bowel, small bowel, stomach, and prostate. Unlike pleckstrin 1, this newly discovered protein does not contain obvious sites of PKC phosphorylation, and in transfected Cos-7 cells, it is a poor substrate for phosphorylation, even after PMA stimulation. Cells expressing pleckstrin 2 undergo a dramatic shape change associated with actin rearrangement, including a loss of central F-actin and a redistribution of actin toward the cell cortex. Overexpression of pleckstrin 2 causes large lamellipodia and peripheral ruffle formation. A variant of pleckstrin 2 lacking both PH domains still had some membrane binding but did not efficiently induce lamellipodia, suggesting that the PH domains of pleckstrin 2 contribute to lamellipodia formation. This work describes a novel, widely expressed, membrane-associating protein and suggests that pleckstrin 2 may help orchestrate cytoskeletal arrangement.


Asunto(s)
Actinas/metabolismo , Tamaño de la Célula/fisiología , Proteínas de la Membrana/metabolismo , Secuencia de Aminoácidos , Animales , Células COS , Clonación Molecular , Cartilla de ADN , ADN Complementario , Femenino , Humanos , Masculino , Mamíferos , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Ratones , Datos de Secuencia Molecular , Especificidad de Órganos , Fosforilación , Reacción en Cadena de la Polimerasa , Proteína Quinasa C/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transfección , Dominios Homologos src
17.
Metabolism ; 48(5): 558-63, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10337853

RESUMEN

To study the effects of lithium supplementation on the diabetic condition, we measured the lithium concentration in the liver, kidney, and muscle from streptozotocin (STZ)-induced diabetic male Sprague-Dawley (SD) rats that were either treated or untreated with peroral lithium carbonate (0.3 mg/mL). The data showed that the lithium content of the liver and muscle was significantly lower in STZ rats than in normal control rats (0.22 +/- 0.05 v 1.30 +/- 0.15, P < .01, and 0.79 +/- 0.30 v 2.48 +/- 2.00 microg/g, respectively). After 4 weeks of lithium carbonate supplementation, we found that (1) the lithium content of the liver and muscle returned to the normal range, (2) the extent of STZ-mediated destruction of beta cells in the pancreas decreased, (3) fasting blood glucose (FBG) and 2-hour postprandial blood glucose (PBG) decreased (P < .05), (4) among the indicators of oxidative stress and antioxidant defenses, blood lipid peroxidate (LPO) decreased and erythrocyte superoxide dismutase (RBC-SOD) and glutathione (GSH) returned to normal, and (5) hepatic LPO decreased and glutathione peroxidase (GSH-Px) increased. These results suggest that the restoration of lithium to control levels in the liver and muscle of diabetic animals is associated not only with decreased blood glucose but also with reduced oxidative stress, and consequently with the protection of insulin-secreting pancreatic islet cells.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Carbonato de Litio/administración & dosificación , Litio/metabolismo , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Suplementos Dietéticos , Insulina/sangre , Islotes Pancreáticos/patología , Carbonato de Litio/farmacología , Masculino , Estrés Oxidativo/fisiología , Ratas , Ratas Sprague-Dawley
18.
J Biol Chem ; 274(11): 7095-102, 1999 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-10066767

RESUMEN

The p38 mitogen-activated protein kinases (MAPK) play a crucial role in stress and inflammatory responses and are also involved in activation of the human immunodeficiency virus gene expression. We have isolated the murine cDNA clones encoding p38-delta MAPK, and we have localized the p38-delta gene to mouse chromosome 17A3-B and human chromosome 6p21.3. By using Northern and in situ hybridization, we have examined the expression of p38-delta in the mouse adult tissues and embryos. p38-delta was expressed primarily in the lung, testis, kidney, and gut epithelium in the adult tissues. Although p38-delta was expressed predominantly in the developing gut and the septum transversum in the mouse embryo at 9.5 days, its expression began to be expanded to many specific tissues in the 12.5-day embryo. At 15.5 days, p38-delta was expressed virtually in most developing epithelia in embryos, suggesting that p38-delta is a developmentally regulated MAPK. Interestingly, p38-delta and p38-alpha were similar serine/threonine kinases but differed in substrate specificity. Overall, p38-delta resembles p38-gamma, whereas p38-beta resembles p38-alpha. Moreover, p38-delta is activated by environmental stress, extracellular stimulants, and MAPK kinase-3, -4, -6, and -7, suggesting that p38-delta is a unique stress-responsive protein kinase.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Citocinas/fisiología , Mediadores de Inflamación/metabolismo , Estrés Oxidativo , Secuencia de Aminoácidos , Secuencia de Bases , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Línea Celular , Mapeo Cromosómico , Cromosomas Humanos Par 6 , Clonación Molecular , ADN Complementario , Activación Enzimática , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
19.
Free Radic Res ; 28(1): 15-24, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9554829

RESUMEN

The possible involvement of oxidative damage and antioxidant protection has been suggested in the pathogenesis of stroke which is the second-leading cause of death in Taiwan. In this study we investigated the relationship between ischemic stroke and plasma status of antioxidants and oxidative products. Plasma levels of vitamin A, alpha-tocopherol, carotenoids, selenium (Se), total SH groups (T-SH), thiobarbituric acid-reactive substances (TBARS) and protein carbonyl, a marker of protein damage, were determined in ischemic-stroke patients (n = 36, blood sampled within 24 hrs after the clinical event) in comparison with 21 matched controls. The cholesterol-adjusted carotenoids and vitamin E were significantly lower (P < 0.05) in the plasma of ischemic-stroke patients than those of the controls. TBARS were higher (P < 0.05) in the patients than in the controls but Se, T-SH and protein carbonyls were not significantly different between the two groups. Separation of the patients into small-artery ischemic stroke (SAIS, n = 17) and large-artery ischemic stroke (LAIS, n = 19) groups revealed that both carotenoids/cholesterol and vitamin E/cholesterol ratios were significantly lower in both LAIS and SAIS groups than the controls (n = 21) while vitamin A/cholesterol was not different among the three groups. TBARS were only significantly higher in the LAIS group. The results demonstrated that, within 24 hrs after the clinical event, the acute-ischemic stroke patients had lowered levels of cholesterol-adjusted carotenoids and alpha-tocopherol but elevated levels of TBARS in the plasma as compared to the matched controls. It remains to be resolved as to whether enhanced lipid peroxidation is a cause or a result of lowered antioxidants in ischemic stroke.


Asunto(s)
Antioxidantes/metabolismo , Isquemia Encefálica/sangre , Trastornos Cerebrovasculares/sangre , Selenio/sangre , Compuestos de Sulfhidrilo/sangre , Vitaminas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Carotenoides/sangre , Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Taiwán , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Vitamina A/sangre , Vitamina E/sangre
20.
Miner Electrolyte Metab ; 23(1): 7-12, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9058363

RESUMEN

The mechanism of colonic phosphate absorption is not well defined. We measured unidirectional phosphate fluxes across rat distal colon epithelium in the absence of transepithelial electrochemical gradients. Steady-state mucosal-to-serosal flux (Jms) was not different from the serosal-to-mucosal flux (Jsm), generating no net flux (Jnet = Jms - Jsm, was not different from "0'). Simultaneous fluxes of mannitol, a paracellular probe, exhibited an identical flux pattern, suggesting that phosphate flux across the colonic epithelium may be mediated through the paracellular pathway. Tight junction permeability was increased with mucosal addition of taurodeoxycholate (TDC, 2 mM) which caused a prompt increase in transepithelial conductance from 7.03 +/- 0.35 to 13.88 +/- 0.35 mS/cm2 (p < 0.001). This was associated with an increase in Jsm, but no change in Jms, for mannitol, resulting in a net flux in the secretary direction. Identical TDC-induced changes were observed in phosphate fluxes, again suggesting phosphate permeation through the intercellular, mannitol pathway. A significant correlation was observed between the permeability of phosphate and the permeability of mannitol, measured both in the mucosal-to-serosal and the serosal-to-mucosal directions and under both control and experimental (mucosal TDC) conditions. Thus, colonic phosphate transport is mediated through the paracellular pathway and enema with high phosphate concentrations (1,760 times blood concentration), can trigger rapid and massive phosphate absorption through this diffusive pathway.


Asunto(s)
Colon/metabolismo , Enema/efectos adversos , Absorción Intestinal , Fosfatos/farmacocinética , Animales , Masculino , Manitol/farmacocinética , Permeabilidad , Fosfatos/sangre , Ratas , Ratas Wistar , Ácido Taurodesoxicólico/farmacología , Uniones Estrechas/metabolismo
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