RESUMEN

Clathrin-mediated vesicular formation and trafficking are responsible for molecular cargo transport and signal transduction among organelles. Our previous study shows that CHLOROPLAST VESICULATION (CV)-containing vesicles (CVVs) are generated from chloroplasts for chloroplast degradation under abiotic stress. Here, we show that CV interacts with the clathrin heavy chain (CHC) and induces vesicle budding toward the cytosol from the chloroplast inner envelope membrane. In the defective mutants of CHC2 and the dynamin-encoding DRP1A, CVV budding and releasing from chloroplast are impeded. The mutations of CHC2 inhibit CV-induced chloroplast degradation and hypersensitivity to water stress. Moreover, CV-CHC2 interaction is impaired by the oxidized GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE (GAPC). GAPC1 overexpression suppresses CV-mediated chloroplast degradation and hypersensitivity to water stress, while CV silencing alleviates the hypersensitivity of the gapc1gapc2 plant to water stress. Together, our work identifies a pathway of clathrin-assisted CVV budding outward from chloroplast, which is involved in chloroplast degradation and stress response.

Asunto(s)

Proteínas de Arabidopsis , Arabidopsis , Humanos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Deshidratación/metabolismo , Cloroplastos/metabolismo , Clatrina/metabolismo , Endocitosis/fisiología

RESUMEN

Maternal environmental factors have been demonstrated to exert significant influences on the health of offspring. The hypothalamic-pituitary-adrenal (HPA) axis is an important neuroendocrine stress system that can be influenced by early life challenges. Our previous research has revealed that the consumption of a high-fat diet (HFD) by pregnant and lactating rats leads to the programming of HPA axis activity in male offspring of the first generation (referred to as F1HFD/C). The present study aimed to investigate whether the observed remodeling of the HPA axis could be inherited by second-generation male offspring (referred to as F2HFD/C), following maternal HFD exposure. The results showed that F2HFD/C rats exhibited enhanced basal HPA axis activity, similar to their F1HFD/C ancestors. Moreover, F2HFD/C rats displayed exacerbated corticosterone responses to restraint and lipopolysaccharide-induced stress, but not to insulin-induced hypoglycemia stress. Furthermore, maternal HFD exposure significantly aggravated depression-like behavior in the F2 generation subjected to chronic unpredictable mild stress. To investigate the role of central calcitonin gene-related peptide (CGRP) signaling in maternal diet-induced programming of the HPA axis across generations, we conducted central infusion of αCGRP8-37, a CGRP receptor antagonist, in F2HFD/C rats. The results demonstrated that αCGRP8-37 attenuated depression-like behaviors and reduced the hyperresponsiveness of the HPA axis to restraint stress in these rats. Therefore, central CGRP signaling may contribute to maternal diet-induced programming of HPA axis across generations. In conclusion, our study provides evidence that maternal HFD consumption can lead to multigenerational programming of the HPA axis and behaviors in adult male descendants.

Asunto(s)

Dieta Alta en Grasa , Efectos Tardíos de la Exposición Prenatal , Embarazo , Femenino , Humanos , Ratas , Animales , Masculino , Dieta Alta en Grasa/efectos adversos , Sistema Hipotálamo-Hipofisario , Péptido Relacionado con Gen de Calcitonina/farmacología , Lactancia , Sistema Hipófiso-Suprarrenal , Corticosterona/farmacología

RESUMEN

The daphnezomine A-type subfamily of Daphniphyllum alkaloids structurally features a unique aza-adamantane core skeleton and anticipates efficient strategies for completing their syntheses to thoroughly investigate their biological activities. Herein, divergent total syntheses of (-)-daphnezomines A and B and (+)-dapholdhamine B have been accomplished in 16-20 steps from a known epoxide via rapid construction of a common core intermediate. The present work features a Ti-mediated radical cyclization to establish the azabicyclo[3.3.1]nonane ring system, an intramolecular Heck reaction to install the bridgehead all-carbon quaternary stereocenter, a tandem deprotection/reduction/keto amine-carbinolamine tautomerization to furnish the aza-adamantane backbone, and an NIS-promoted 6-endo-trig aminocyclization to assemble the (+)-dapholdhamine B backbone.

Asunto(s)

Adamantano , Alcaloides , Estereoisomerismo , Ciclización

RESUMEN

Schisandra chinensis (S. chinensis) is one of the core drugs used for relieving cough and asthma in traditional Chinese medicine. However, there are few basic studies on the treatment of respiratory diseases with S. chinensis in modern pharmacology, and the material basis and mechanism of its antiasthmatic effect are still unclear. Lignans are the main active components of S. chinensis. The aim of this study was to observe the relaxation effect of S. chinensis lignans (SCL) on the tracheal smooth muscle of rats by in vitro tracheal perfusion experiments, and to explore the mechanism by preincubation with L-type calcium channel blocker verapamil, four potassium channel blockers glibenclamide, tetraethylamine, 4-aminopyridine and barium chloride (BaCl2), ß-adrenoceptor blocker propranolol, nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME), and the cyclooxygenase inhibitor indomethacin, respectively. The results showed that SCL (0.25-1.75 mg/mL) reduced the contraction of isolated tracheal smooth muscle induced by acetylcholine, the preincubation with verapamil and glibenclamide could attenuate the relaxation effect, whereas propranolol, 4-aminopyridine, BaCl2, tetraethylamine, L-NAME, and indomethacin had no such effect. These results suggest that SCL has a significant relaxation effect on the isolated tracheal smooth muscle of rats, and the mechanism may be related to the inhibition of extracellular calcium influx and intracellular calcium release from the sarcoplasmic reticulum, as well as the activation of ATP-sensitive potassium channels. These findings may provide a pharmacological basis for the traditional use of S. chinensis to treat asthma.

Asunto(s)

Lignanos , Schisandra , Animales , Bloqueadores de los Canales de Calcio/farmacología , Lignanos/farmacología , Relajación Muscular , Músculo Liso , Óxido Nítrico , Bloqueadores de los Canales de Potasio/farmacología , Ratas

RESUMEN

Dynamic therapy, such as photodynamic therapy (PDT) or chemodynamic therapy (CDT), is one of the most promising therapeutic strategies for tumors. Integrating the advantages of near-infrared-induced PDT and CDT can potentially improve the therapeutic performance. A single primitive nanostructure, CuWO4 nanodots, was developed. It could generate reactive oxygen species under 808 nm light irradiation and release copper ions into the acid tumor microenvironment, thereby boosting Fenton-like reactions. The PDT and CDT would occur when the nanodots were introduced into the tumor tissue and irradiated under 808 nm light. The results of combined PDT and CDT antitumor studies showed the effective inhibition of tumor tissue growth, thereby suggesting that the nanodots are candidate agents for synergistic antitumor applications.

Asunto(s)

Cobre/química , Nanoestructuras/química , Óxidos/química , Fotoquimioterapia/métodos , Espectroscopía Infrarroja Corta/métodos , Tungsteno/química , Línea Celular Tumoral , Humanos , Fármacos Fotosensibilizantes/farmacología , Análisis Espectral/métodos , Microambiente Tumoral/efectos de los fármacos

RESUMEN

AIMS: Schisandra is a good choice in Traditional Chinese Medicine for the therapy of cardiovascular diseases, but whether it contains a or some specific component (s) responsible these effects are still unclear. In the present study, we explored whether Schisantherin A (SCA) causes vasorelaxation in isolated rat thoracic aorta. MAIN METHODS: We selected SCA, one of the main monomers of lignans from Schisandra, to examine its vasorelaxant effect on the isolated rat thoracic aorta and also exploited several tool inhibitors to probe its underlying mechanisms. KEY FINDINGS: SCA produced relaxation concentration-dependently on the endothelium-intact (43.56 ± 2.17%) and endothelium-denuded thoracic aorta strips (18.76 ± 3.95%) pre-contracted by phenylephrine (PE). However, after treated with indomethacin or L-NAME, SCA showed only partial vasorelaxant effects. Whereas, this vasorelaxation by SCA was not changed with specific K+-channel inhibitors, i.e. barium chloride (BaCl2), 4-aminopyridine (4-AP), tetraethylamine (TEA), and glibenclamide. SCA had no effect on the aorta strips pre-contracted by PE in neither Ca2+-free nor CaCl2 conditions. But, in the Ca2+ free and high K+ environment, SCA partly abolished the vasocontraction induced by CaCl2. SIGNIFICANCE: It was the first report to demonstrate that SCA had endothelium-dependent and -independent vasorelaxant effects on the isolated rat thoracic aorta, and the underlying mechanisms might be involved into its promoting the production of nitric oxide (NO) and prostacyclin (PGI2), and inhibiting the voltage-dependent calcium channels (VDCCs) opening. This study may partially explain the use of Schisandra in cardiovascular diseases and facilitate further drug development as well.

Asunto(s)

Aorta Torácica/efectos de los fármacos , Ciclooctanos/farmacología , Dioxoles/farmacología , Endotelio Vascular/efectos de los fármacos , Lignanos/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología , Animales , Aorta Torácica/fisiología , Western Blotting , Calcio/metabolismo , Relación Dosis-Respuesta a Droga , Endotelio Vascular/fisiología , Masculino , Bloqueadores de los Canales de Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa

RESUMEN

Maternal environmental factors such as diet have profound effects on offspring development and later health. The hypothalamic-pituitary-adrenal (HPA) axis is an important stress neuroendocrine system that is subject to programming by early life challenges. The present study was further to investigate whether maternal high fat diet (HFD) exposure during rat pregnancy and lactation can alter the HPA axis activity in adult male offspring. We observed that maternal HFD consumption exerted long-term effects on the basal activity of the HPA axis in adult offspring, with increased mean plasma corticosterone levels that result from elevated steroid pulse frequence and pulse amplitude. More importantly, maternal HFD offspring displayed enhanced corticosterone responses to restraint (1 h) and lipopolysaccharide (25 µg/kg, iv) but not insulin-induced hypoglycemia (0.3U/kg, iv) stress, suggesting a stressor-specific effect of maternal diet on the hyperresponsiveness of the HPA axis to stress. Additionally, maternal HFD exposure markedly attenuated the habituation of HPA responses to repeated restraint stress. These findings demonstrate that perinatal HFD exposure has a potent and long-lasting influence on development of neuroendocrine regulatory mechanisms. Maternal HFD consumption significantly increased basal corticotropin-releasing factor (CRF) mRNA expression in the paraventricular nucleus; nevertheless, similar increments in CRF mRNA levels following restraint were observed between maternal HFD offspring and control rats. Furthermore, the medial and central nuclei of amygdala played a pivotal role in maternal HFD-induced sensitization of the HPA response to psychological and systemic stress, respectively, suggesting that different neural pathways may mediate maternal HFD-induced HPA hyperresponsivity to different types of stressors. Take together, the long-term effects of maternal HFD challenge on the central regulation of the HPA axis, therefore, expose the adult offspring to greater HPA function throughout lifespan, in stressor-specific and region-specific manner.

Asunto(s)

Dieta Alta en Grasa/efectos adversos , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Encéfalo/metabolismo , Corticosterona/sangre , Corticosterona/metabolismo , Hormona Liberadora de Corticotropina/metabolismo , Grasas de la Dieta/metabolismo , Femenino , Hipocampo/metabolismo , Masculino , Núcleo Hipotalámico Paraventricular/metabolismo , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Restricción Física , Estrés Psicológico/metabolismo

RESUMEN

Maternal environmental factors such as diet have consequences on later health of the offspring. We found that maternal high-fat diet (HFD) exposure renders adult offspring brain more susceptible to ischemic injury. The present study was further to investigate whether HFD consumption during rat pregnancy and lactation influences the cerebral vasculature in adult male offspring. Besides the endothelial damage observed in the transmission electron microscopy, the MCAs of offspring from fat-fed dams fed with control diet (HFD/C) also displayed increased wall thickness and media/lumen ratio, suggesting that cerebrovascular hypertrophy or hyperplasia occurs. Moreover, smaller lumen diameter and elevated myogenic tone of the MCAs over a range of intralumenal pressures indicate inward cerebrovascular remodeling in HFD/C rats, with a concomitant increase in vessel stiffness. More importantly, both wire and pressure myography demonstrated that maternal HFD intake also enhanced the MCAs contractility to ET-1, accompanied by increases in ET types A receptor (ETAR) but not B (ETBR) density in the arteries. Furthermore, ETAR antagonism but not ETBR antagonism restored maternal HFD-induced cerebrovascular dysfunction in adult offspring. Taken together, maternal diet can substantially influence adult offspring cerebrovascular health, through remodeling of both structure and function, at least partially in an ET-1 manner.

Asunto(s)

Circulación Cerebrovascular/fisiología , Dieta Alta en Grasa/efectos adversos , Arteria Cerebral Media/fisiopatología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Animales , Femenino , Embarazo , Ratas , Ratas Sprague-Dawley , Vasoconstricción/fisiología

RESUMEN

The sonic hedgehog (SHH) signaling pathway plays a critical role in embryonic development, tissue regeneration and organogenesis. The activation of SHH signaling produces profibrogenic effects in various tissues, such as the liver and the biliary ducts. However, the role of SHH signaling in renal fibrogenesis remains to be elucidated. For this purpose, in the present study, we evaluated the hypothesis that activated SHH signaling promotes the acquisition of a myofibroblastic phenotype through the epithelial-mesenchymal transition (EMT), resulting in renal interstitial fibrosis (RIF). Kidney samples from rats subjected to unilateral or bilateral ureteral obstruction exhibited the enhanced expression of SHH-pathway proteins, mesenchymal markers and the decreased expression of epithelial markers. Overactive SHH signaling as well as tubular EMT and RIF in the obstructed kidneys were inhibited by recanalization of the ureter. In vitro, SHH signaling was activated during EMT induction and extracellular matrix (ECM) deposition was observed in transforming growth factor-ß1 (TGF-ß1)-treated renal tubular epithelial cells [RTECs; NRK-52E cell line]. Exogenous SHH activated SHH signaling and resulted in the upregulated expression of mesenchymal genes, the profibrogenic cytokine TGF-ß1, and the downregulated expression of epithelial markers. The blockade of SHH signaling with cyclopamine abolished SHH-mediated EMT as well as the acquisition of a myofibroblastic phenotype, and decreased TGF-ß1 expression and ECM production. Thus, taken together, these findings demonstrate that the activation of the SHH signaling pathway promotes the induction of EMT and renal tubulointerstitial fibrosis. The pharmacological inhibition of SHH signaling may potentially be of therapeutic value in the management of fibrotic kidney diseases.

Asunto(s)

Transición Epitelial-Mesenquimal , Proteínas Hedgehog/metabolismo , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Animales , Biomarcadores , Modelos Animales de Enfermedad , Matriz Extracelular/metabolismo , Fibrosis , Enfermedades Renales/etiología , Masculino , Ratas , Transducción de Señal , Factor de Crecimiento Transformador beta1/metabolismo , Obstrucción Ureteral/complicaciones

RESUMEN

OBJECTIVE: To investigate the role of sub-transform macrophage in ischemia/reperfusion renal injury in rats, as well as under-lying mechanisms. METHODS: Thirty male Sprague-Dawley rats were randomly divided into ischemia/reperfusion (IRI, n=24, renal artery was occluded for 45 min) group and sham-operation (Sham, n=6) group. The kidneys in IRI group were collected at 0, 6, 24 and 72 h after operation (6 rats for each time point). The injury of the kidney was detected with HE staining. Immunohistochemistry staining was performed to evaluate the expression of proliferating cell nuclear antigen (PCNA). Real-time PCR was used to detect the mRNA expression of macrophage migration inhibitory factor (MIF). Moreover, the expression and location of MIF, monocyte chemoattractant protein-1 (MCP-1) and macrophage marker CD68 were examined by immunofluorescence staining. Most importantly, the distribution of macrophage subtypes M1 and M2 was analyzed by flow cytometry. RESULTS: The worst pathologic damage of the renal tissues, as well as infiltration of inflammatory cells, was observed at 24 h after operation in IRI rats, with obvious recovery afterwards. Immunohistochemistry staining showed that the expression of PCNA was significantly increased after the ischemia/reperfusion, peaking at 6 h and reducing at 72 h after operation. Compared with sham group, the levels of MIF at mRNA and protein levels were both significantly increased after the ischemia/reperfusion, while the expression of MCP-1 was peaked at 6 h and decreased afterwards. Moreover, the expression of CD68-positive macrophages were significantly increased in IRI rats, with peaking at 24 h and reducing at 72 h. Furthermore, after 6 h of reperfusion, the percentage of M1 macrophages reached the peak, and thereafter the relative expression of M1 and M2 was reduced and increased, respectively. CONCLUSIONS: In the early phase of ischemia/per-fu sion renal injury, M1 macrophage results in renal damage, and afterwards the M2 macrophage is increased and repairs the renal damage by improving the cell proliferation.

Asunto(s)

Riñón/patología , Macrófagos/citología , Daño por Reperfusión , Lesión Renal Aguda , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Proliferación Celular , Quimiocina CCL2/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley

RESUMEN

Amino acid-derived metabolites, including protein-bound uremic toxins, may have prognostic value for patients with heart failure (HF). The aim of this study was to investigate whether p-cresyl sulfate (PCS), indoxyl sulfate (IS), and arginine metabolites provided prognostic values in addition to the traditional biomarker, B-type natriuretic peptide (BNP), in patients with HF. Chromatography mass spectrometry was performed to measure tyrosine, tryptophan, arginine, PCS, IS, and asymmetric (ADMA) and symmetric dimethylarginine (SDMA) in the plasma from 51 normal controls and 136 HF patients. Compared to the normal controls, PCS levels significantly increased in HF patients (p = 0.003). During the follow-up (2.3 ± 1.1 years), 35 (25.7 %) patients experienced a composite event of death or HF-related re-hospitalization. In univariable analysis, PCS, estimated glomerular filtration rate (eGFR), BNP, DMA/arginine ratio, and ADMA/arginine ratio were associated with a higher rate of composite events. In the multivariable analysis, PCS was the only independent predictor of composite events [hazard ratio (HR) 1.06 (per 10 µM), 95 % confidence interval (CI) 1.01-1.11, p = 0.02]. Kaplan-Meier curves showed that a PCS level of ≥50 µM was significantly associated with a higher composite event rate than those with a PCS level of <50 µM (Log rank = 5.11, p = 0.024; HR 2.13, 95 % CI 1.09-4.16, p = 0.02). In conclusion, among protein-bound uremic toxins, eGFR, and DMA metabolites, increased PCS is the only independent predictor of HF-related events in patients with HF. A combination of PCS and BNP should better risk-stratify patients with HF.

Asunto(s)

Cresoles/sangre , Insuficiencia Cardíaca/sangre , Ésteres del Ácido Sulfúrico/sangre , Adulto , Anciano , Anciano de 80 o más Años , Arginina/sangre , Biomarcadores/sangre , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Cromatografía Liquida , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/terapia , Humanos , Indicán/sangre , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Péptido Natriurético Encefálico/sangre , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Riesgo , Espectrometría de Masa por Ionización de Electrospray , Factores de Tiempo , Regulación hacia Arriba , Adulto Joven

RESUMEN

Diet-induced epigenetic modifications in early life could contribute to later health problem. However, it remains to be established whether high-fat diet (HFD) consumption during pregnancy and the suckling period could predispose the offspring to stroke. The present study investigated the influence of maternal HFD on stroke outcome in adult offspring. Female Sprague-Dawley rats were fed a normal diet (5.3% fat) or a HFD (25.7% fat), just before pregnancy until the end of lactation. Male offspring were fed with the control diet or the HFD after weaning, to form four groups (control offspring fed with the control diet (C/C) or the HFD (C/HFD) and offspring of fat-fed dams fed with the control diet (HFD/C) or the HFD (HFD/HFD)). The offspring received middle cerebral artery occlusion on day 120 followed by behavioral tests (neurological deficit score, staircase-reaching test and beam-traversing test), and infarct volumes were also calculated. We found that the HFD/C rats displayed larger infarct volume and aggravated functional deficits (all P<0.05), compared with the C/C rats, indicating that maternal fat-rich diet renders the brain more susceptible to the consequences of ischemic injury. Moreover, maternal HFD offspring displayed elevated glucocorticoid concentrations following stroke, and increased glucocorticoid receptor expression. In addition, adrenalectomy reversed the effects of maternal HFD on stroke outcome when corticosterone was replaced at baseline, but not ischemic, concentrations. Furthermore, expression of brain-derived neurotrophic factor (BDNF) in the ipsilateral hippocampus was decreased in the HFD/C offspring (P<0.05), compared with the C/C offspring. Taken together, maternal diet can substantially influence adult cerebrovascular health, through the programming of central BDNF expression and the hypothalamic-pituitary-adrenal axis.

Asunto(s)

Dieta Alta en Grasa/efectos adversos , Hipocampo/patología , Infarto de la Arteria Cerebral Media/patología , Efectos Tardíos de la Exposición Prenatal/patología , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Corticosterona/sangre , Susceptibilidad a Enfermedades , Femenino , Expresión Génica , Hipocampo/irrigación sanguínea , Hipocampo/metabolismo , Infarto de la Arteria Cerebral Media/sangre , Infarto de la Arteria Cerebral Media/etiología , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/etiología , Fenómenos Fisiologicos de la Nutrición Prenatal , Ratas Sprague-Dawley , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo

RESUMEN

Early life exposure to specific environmental factors can contribute to development of behavioral disorders in adulthood. Although maternal high fat diet (HFD) consumption during the perinatal period has been reported to program offspring behavior, the underlying mechanisms remain to be elucidated. The present study was designed to evaluate the influence of maternal HFD on offspring behavior under nonstressed and stressful conditions, using male Sprague-Dawley offspring, which mothers were fed with HFD or normal diet (ND), receiving chronic unpredictable mild stress (CUMS) in the adulthood. We found that although the detrimental effects of maternal HFD consumption on offspring depressive behavior did not persist into adulthood, it markedly aggravated the behavioral disorder response to stressful challenge in adult offspring. Moreover, calcitonin gene-related peptide (CGRP) concentration in CSF and hippocampus were increased in the HFD+CUMS rats, compared to the ND+CUMS subjects. Another separate groups were fitted with intracerebroventricular (icv) cannulae. Central infusion of αCGRP8-37, a CGRP antagonist, produced antidepressant effects in HFD+CUMS rats, implying that the programming of maternal HFD on offspring behavior responses to stress may be mediated partially by endogenous central CGRP signaling. Moreover, we found that maternal HFD significantly exacerbated HPA profile response to acute restraint stress and attenuated the habituation of HPA responses to repeated restraint stress, suggesting that maternal HFD may program the changes of HPA-regulatory mechanisms. Overall, our findings suggest that maternal HFD influence adult depressive disorder response to stressful challenge, through the modulation of endogenous central CGRP signaling and HPA-regulatory components.

Asunto(s)

Trastorno Depresivo/fisiopatología , Dieta Alta en Grasa/efectos adversos , Hipocampo/fisiopatología , Efectos Tardíos de la Exposición Prenatal , Estrés Psicológico/fisiopatología , Animales , Antidepresivos/farmacología , Péptido Relacionado con Gen de Calcitonina/antagonistas & inhibidores , Péptido Relacionado con Gen de Calcitonina/metabolismo , Péptido Relacionado con Gen de Calcitonina/farmacología , Catéteres de Permanencia , Enfermedad Crónica , Trastorno Depresivo/tratamiento farmacológico , Grasas de la Dieta/efectos adversos , Modelos Animales de Enfermedad , Femenino , Habituación Psicofisiológica/efectos de los fármacos , Habituación Psicofisiológica/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/crecimiento & desarrollo , Masculino , Fragmentos de Péptidos/farmacología , Embarazo , Distribución Aleatoria , Ratas Sprague-Dawley , Estrés Psicológico/tratamiento farmacológico , Incertidumbre

RESUMEN

Stress exerts profound inhibitory effects on reproductive function by suppression of the pulsatile release of GnRH and therefore LH. Besides the corticotrophin-releasing factor (CRF), this effect also might be mediated via GABAergic signaling within the arcuate nucleus (ARC) since its inhibitory effects on LH pulses and increased activity during stress. In the present study, we investigated the role of endogenous GABAergic signaling within the ARC in stress-induced suppression of LH pulses. Ovariectomised oestradiol-replaced rats were implanted with bilateral and unilateral cannulae targeting toward the ARC and lateral cerebral ventricle respectively. Blood samples (25 µl) were taken via chronically implanted cardiac catheters every 5 min for 6 h for measurement of LH pulses. Intra-ARC infusion of GABAA receptor antagonist, bicuculline (0.2 pmol in 200 nl artificial cerebrospinal fluid (aCSF) each side, three times at 20-min intervals) markedly attenuated the inhibitory effect of lipopolysaccharide (LPS; 25 µg/kg i.v.) but not restraint (1 h) stress on pulsatile LH secretion. In contrast, restraint but not LPS stress-induced suppression of LH pulse frequency was reversed by intra-ARC administration of GABABR antagonist, CGP-35348 (1.5 nmol in 200 nl aCSF each side, three times at 20-min intervals). Moreover, intra-ARC application of either bicuculline or CGP-35348 attenuated the inhibitory effect of CRF (1 nmol in 4 µl aCSF, i.c.v.) on the LH pulses. These data indicate a pivotal and differential role of endogenous GABAA and GABAB signaling mechanisms in the ARC with respect to mediating immunological and psychological stress-induced suppression of the GnRH pulse generator respectively.

Asunto(s)

Núcleo Arqueado del Hipotálamo/metabolismo , Hormona Luteinizante/metabolismo , Estrés Fisiológico/fisiología , Ácido gamma-Aminobutírico/metabolismo , Animales , Núcleo Arqueado del Hipotálamo/efectos de los fármacos , Bicuculina/farmacología , Núcleos Cerebelosos/efectos de los fármacos , Núcleos Cerebelosos/metabolismo , Hormona Liberadora de Corticotropina/metabolismo , Estradiol/metabolismo , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Compuestos Organofosforados/farmacología , Pulso Arterial/métodos , Ratas , Receptores de GABA/metabolismo , Estrés Fisiológico/efectos de los fármacos

RESUMEN

Epithelial-to-mesenchymal transition (EMT), a biologic process in which tubular cells lose their epithelial phenotypes and acquire new characteristic features of mesenchymal properties, is increasingly recognized as an integral part of renal tissue fibrogenesis. Recent studies indicate that resveratrol, a botanical compound derived mainly from the skins of red grapes, may have anti-fibrotic effects in many tissues, but the potential molecular mechanism remains unknown. In the present study, we identified that resveratrol inhibits the induction of EMT and deposition of extracellular matrix (ECM) through antagonizing the hedgehog pathway in vitro and in vivo. In rats with unilateral ureteral obstruction (UUO), administration of resveratrol (20mg/kg/day) significantly reduced serum creatinine. Resveratrol also decreased expression of TGF-ß1, and inhibited the phenotypic transition from epithelial cells to mesenchymal cells, and the deposition of ECM in UUO rats. In cultured renal tubular epithelial cells (NRK-52E), TGF-ß1-induced EMT and ECM synthesis was abolished with the treatment of resveratrol. The induction of EMT was associated with the activation of the hedgehog pathway. Resveratrol treatment markedly inhibited the over-activity of the hedgehog pathway in the obstructed kidney and in TGF-ß1-treated NRK-52E cells, resulted in reduction of cellular proliferation, EMT and ECM accumulation. Thus, these results suggest that resveratrol is able to inhibit EMT and fibrosis in vivo and in vitro through antagonizing the hedgehog pathway, and resveratrol may have therapeutic potential for patients with fibrotic kidney diseases.

Asunto(s)

Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibrosis/tratamiento farmacológico , Riñón/patología , Estilbenos/farmacología , Animales , Línea Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Fibrosis/metabolismo , Proteínas Hedgehog/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Túbulos Renales/citología , Túbulos Renales/efectos de los fármacos , Masculino , Ratas Sprague-Dawley , Receptores Acoplados a Proteínas G/metabolismo , Resveratrol , Transducción de Señal/efectos de los fármacos , Receptor Smoothened , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Obstrucción Ureteral/fisiopatología

RESUMEN

AIMS: Sedum sarmentosum Bunge, a traditional Chinese herbal medicine, has a wide range of clinical effects, including anti-oxidation, anti-inflammation, and anti-cancer properties. In this study, we determined whether S. sarmentosum Bunge Extract (SSBE) has anti-fibrotic effects on renal tissues. MAIN METHODS: We investigated the effects of SSBE on aristolochic acid (AA)-induced injury to renal tubular epithelial cells (RTECs) in vitro and unilateral ureteral obstruction (UUO)-induced renal fibrosis in vivo by evaluating epithelial-to-mesenchymal transition (EMT) and the accumulation of extracellular matrix (ECM) components. Furthermore, we examined the expression levels of TGF-ß1 and its receptor. KEY FINDINGS: In cultured RTECs (NRK-52E), AA promoted renal EMT and ECM accumulation by up-regulating the expression of mesenchymal markers and ECM components and by down-regulating the expression of epithelial markers. In addition, AA induced an imbalance between MMP-2 and TIMP-2 and enhanced expression of TGF-ß1 and its receptor. SSBE treatment significantly inhibited AA-induced TGF-ß1 expression and prevented the induction of EMT and deposition of ECM. In the UUO rats, tubular injury and interstitial fibrosis were obviously increased. SSBE administration protected renal function, as indicated by reduced serum creatinine levels, and alleviated renal interstitial fibrosis. These anti-fibrotic effects were associated with a reduction in TGF-ß1 expression and inhibition of EMT and ECM accumulation. SIGNIFICANCE: These findings suggest that SSBE may have therapeutic potential for fibrotic kidney diseases.

Asunto(s)

Medicamentos Herbarios Chinos/farmacología , Células Epiteliales/efectos de los fármacos , Fibrosis/tratamiento farmacológico , Túbulos Renales/patología , Fitoterapia/métodos , Extractos Vegetales/farmacología , Sedum/química , Análisis de Varianza , Animales , Ácidos Aristolóquicos/toxicidad , Células Cultivadas , Cartilla de ADN/genética , Ensayo de Inmunoadsorción Enzimática , Transición Epitelial-Mesenquimal/efectos de los fármacos , Matriz Extracelular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Túbulos Renales/citología , Túbulos Renales/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa

Asunto(s)

Transición Epitelial-Mesenquimal , Riñón/patología , Obstrucción Ureteral/patología , Animales , Fibrosis , Túbulos Renales/citología , Masculino , Ratas , Ratas Sprague-Dawley

RESUMEN

AIM: To investigate the relationship between polymorphisms present in the vitamin D receptor (VDR) gene and colorectal cancer risk, a systematic meta-analysis of population-based studies was performed. METHODS: A total of 38 relevant reports published between January 1990 and August 2010 were identified, of which only 23 qualified for this meta-analysis based on our selection criteria. Five polymorphic variants of the VDR gene, including Cdx-2 (intron 1e) and FokI (exon 2) present in the 5' region of the gene, and BsmI (intron 8), ApaI (intron 8), and TaqI (exon 9) sites present in the 3' untranslated region (UTR), were evaluated for possible associations with colorectal cancer risk. Review manager 4.2 was used to perform statistical analyses. RESULTS: In the meta-analysis performed, only the BsmI polymorphism was found to be associated with colorectal cancer risk. In particular, the BsmI B genotype was found to be related to an overall decrease in the risk for colorectal cancer [BB vs bb: odds ratio (OR) = 0.87, 95% CI: 0.80-0.94, P = 3 × 10(-4); BB vs Bb + bb: OR = 0.90, 95% CI: 0.84-0.97, P = 5 × 10(-4)]. Moreover, in subgroup analyses, the BsmI B genotype was significantly associated with colon cancer, and not rectal cancer. An absence of between-study heterogeneity was also observed. CONCLUSION: A meta-analysis of 23 published studies identified the BsmI polymorphism of the VDR gene to be associated with an increased risk of colon cancer.

Asunto(s)

Neoplasias Colorrectales/genética , Polimorfismo Genético , Receptores de Calcitriol/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Oportunidad Relativa , Factores de Riesgo