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1.
Mol Ther Methods Clin Dev ; 23: 370-389, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34761052

RESUMEN

Delivery of adeno-associated viral vectors (AAVs) to cerebrospinal fluid (CSF) has emerged as a promising approach to achieve widespread transduction of the central nervous system (CNS) and peripheral nervous system (PNS), with direct applicability to the treatment of a wide range of neurological diseases, particularly lysosomal storage diseases. Although studies in small animal models have provided proof of concept and experiments in large animals demonstrated feasibility in bigger brains, there is not much information on long-term safety or durability of the effect. Here, we report a 7-year study in healthy beagle dogs after intra-CSF delivery of a single, clinically relevant dose (2 × 1013 vg/dog) of AAV9 vectors carrying the canine sulfamidase, the enzyme deficient in mucopolysaccharidosis type IIIA. Periodic monitoring of CSF and blood, clinical and neurological evaluations, and magnetic resonance and ultrasound imaging of target organs demonstrated no toxicity related to treatment. AAV9-mediated gene transfer resulted in detection of sulfamidase activity in CSF throughout the study. Analysis at tissue level showed widespread sulfamidase expression and activity in the absence of histological findings in any region of encephalon, spinal cord, or dorsal root ganglia. Altogether, these results provide proof of durability of expression and long-term safety for intra-CSF delivery of AAV-based gene transfer vectors encoding therapeutic proteins to the CNS.

2.
Expert Opin Pharmacother ; 22(6): 743-753, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33283570

RESUMEN

ABSTARCTIntroduction: Cardiovascular disease (CVD) continues to be an essential cause of morbidity and mortality among people living with human immunodeficiency virus infection (PLWH). Since the bulk of cardiovascular risk (CVR) factors are shared between PLWH and the general population, prevention and treatment strategies are similar. However, there are CVR factors particular to PLWH, which need separate consideration. These factors are those HIV-dependent, those related to HIV-derived consequences, and combination antiretroviral therapy (cART)-dependent.Areas covered: In this review, the authors discuss the management of CVD in PLWH, with a special interest in pharmacological treatment and drug-drug interactions with cART.Expert opinion: In recent years, we have witnessed a decreased CVD morbidity and mortality in PLWH, which probably reflects an improvement in the management of CVR factors and CVD in these patients, partially thanks to new developments in antiretroviral therapy. Therefore, although there is still room for improvement, at present, the old desideratum of equaling PLWH and the general population in terms of CVD incidence and prognosis is a little closer.


Asunto(s)
Enfermedades Cardiovasculares , Infecciones por VIH , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Incidencia
3.
Diabetes ; 69(5): 927-939, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32086292

RESUMEN

Vitamin D deficiency has been associated with increased incidence of diabetes, both in humans and in animal models. In addition, an association between vitamin D receptor (VDR) gene polymorphisms and diabetes has also been described. However, the involvement of VDR in the development of diabetes, specifically in pancreatic ß-cells, has not been elucidated yet. Here, we aimed to study the role of VDR in ß-cells in the pathophysiology of diabetes. Our results indicate that Vdr expression was modulated by glucose in healthy islets and decreased in islets from both type 1 diabetes and type 2 diabetes mouse models. In addition, transgenic mice overexpressing VDR in ß-cells were protected against streptozotocin-induced diabetes and presented a preserved ß-cell mass and a reduction in islet inflammation. Altogether, these results suggest that sustained VDR levels in ß-cells may preserve ß-cell mass and ß-cell function and protect against diabetes.


Asunto(s)
Factor II del Crecimiento Similar a la Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Receptores de Calcitriol/metabolismo , Animales , Glucemia , Diabetes Mellitus , Diabetes Mellitus Experimental , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Glucosa/administración & dosificación , Glucosa/farmacología , Factor II del Crecimiento Similar a la Insulina/genética , Masculino , Ratones , Ratones Endogámicos NOD , Ratones Transgénicos , Receptores de Calcitriol/genética
4.
Nutr Hosp ; 34(4): 907-913, 2017 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-29095016

RESUMEN

INTRODUCTION: Malnutrition is common in patients admitted to hospital and is associated with morbidity and mortality. We conducted a study to assess the prevalence of nutritional risk, risk factors associated and its consequences in a third-level hospital. METHODS: This is a prospective nutritional screening study of hospitalized patients evaluated within the first 72 hours of admission, by Malnutrition Universal Screening Tool (MUST) and Short Nutritional Assessment Questionnaire (SNAQ) screening tests. The variables recorded included demographic, anthropometric, hospitalization and clinical data. RESULTS: Out of 409 patients, 12.7% and 15.3% were nutritionally at risk according to MUST and SNAQ, respectively, with the highest prevalence in critical care units (33.3%; 25.5%), amongst oncologic patients (17.5%; 28.4%) and those with higher Charlson comorbidity indices (CCI). Length of stay (LOS) was longer in patients at severe malnutrition risk (15.4 vs 9.9 days for MUST; 13.3 vs 9.9 days for SNAQ). Mortality was higher in those with high malnutrition risk (66.7% vs 10.9% for MUST; 50.0% vs 14.2% for SNAQ). Multivariate analysis showed that malnutrition was associated with CCI and mortality. Risk factors associated with LOS were admission as emergencies for both MUST and SNAQ tests. CONCLUSIONS: The prevalence of malnutrition is high in patients on admission to a third-level hospital, with a higher prevalence in critical care units, amongst oncologic patients and those with a higher CCI. Malnutrition is associated with longer LOS and higher mortality. The systematic clinical use of screening tools enables to detect patients at risk of malnutrition and take appropriate action.


Asunto(s)
Pruebas Diagnósticas de Rutina , Desnutrición/diagnóstico , Desnutrición/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estado Nutricional , Prevalencia , Estudios Prospectivos , Factores de Riesgo
5.
JCI Insight ; 1(9): e86696, 2016 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-27699273

RESUMEN

Mucopolysaccharidosis type II (MPSII) is an X-linked lysosomal storage disease characterized by severe neurologic and somatic disease caused by deficiency of iduronate-2-sulfatase (IDS), an enzyme that catabolizes the glycosaminoglycans heparan and dermatan sulphate. Intravenous enzyme replacement therapy (ERT) currently constitutes the only approved therapeutic option for MPSII. However, the inability of recombinant IDS to efficiently cross the blood-brain barrier (BBB) limits ERT efficacy in treating neurological symptoms. Here, we report a gene therapy approach for MPSII through direct delivery of vectors to the CNS. Through a minimally invasive procedure, we administered adeno-associated virus vectors encoding IDS (AAV9-Ids) to the cerebrospinal fluid of MPSII mice with already established disease. Treated mice showed a significant increase in IDS activity throughout the encephalon, with full resolution of lysosomal storage lesions, reversal of lysosomal dysfunction, normalization of brain transcriptomic signature, and disappearance of neuroinflammation. Moreover, our vector also transduced the liver, providing a peripheral source of therapeutic protein that corrected storage pathology in visceral organs, with evidence of cross-correction of nontransduced organs by circulating enzyme. Importantly, AAV9-Ids-treated MPSII mice showed normalization of behavioral deficits and considerably prolonged survival. These results provide a strong proof of concept for the clinical translation of our approach for the treatment of Hunter syndrome patients with cognitive impairment.


Asunto(s)
Terapia Genética , Iduronato Sulfatasa/genética , Mucopolisacaridosis II/terapia , Animales , Dependovirus , Modelos Animales de Enfermedad , Femenino , Vectores Genéticos , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL
6.
Dis Model Mech ; 9(9): 999-1013, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27491071

RESUMEN

Mucopolysaccharidosis type IIIC (MPSIIIC) is a severe lysosomal storage disease caused by deficiency in activity of the transmembrane enzyme heparan-α-glucosaminide N-acetyltransferase (HGSNAT) that catalyses the N-acetylation of α-glucosamine residues of heparan sulfate. Enzyme deficiency causes abnormal substrate accumulation in lysosomes, leading to progressive and severe neurodegeneration, somatic pathology and early death. There is no cure for MPSIIIC, and development of new therapies is challenging because of the unfeasibility of cross-correction. In this study, we generated a new mouse model of MPSIIIC by targeted disruption of the Hgsnat gene. Successful targeting left LacZ expression under control of the Hgsnat promoter, allowing investigation into sites of endogenous expression, which was particularly prominent in the CNS, but was also detectable in peripheral organs. Signs of CNS storage pathology, including glycosaminoglycan accumulation, lysosomal distension, lysosomal dysfunction and neuroinflammation were detected in 2-month-old animals and progressed with age. Glycosaminoglycan accumulation and ultrastructural changes were also observed in most somatic organs, but lysosomal pathology seemed most severe in liver. Furthermore, HGSNAT-deficient mice had altered locomotor and exploratory activity and shortened lifespan. Hence, this animal model recapitulates human MPSIIIC and provides a useful tool for the study of disease physiopathology and the development of new therapeutic approaches.


Asunto(s)
Progresión de la Enfermedad , Mucopolisacaridosis III/patología , Acetiltransferasas/deficiencia , Acetiltransferasas/metabolismo , Animales , Conducta Animal , Encéfalo/enzimología , Encéfalo/patología , Modelos Animales de Enfermedad , Glicosaminoglicanos/metabolismo , Homeostasis , Humanos , Inflamación/patología , Longevidad , Lisosomas/metabolismo , Lisosomas/patología , Lisosomas/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/patología , Mucopolisacaridosis III/enzimología , Especificidad de Órganos , Análisis de Supervivencia
7.
Diabetes ; 65(8): 2139-50, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27207555

RESUMEN

Eicosanoids, such as leukotriene B4 (LTB4) and lipoxin A4 (LXA4), may play a key role during obesity. While LTB4 is involved in adipose tissue inflammation and insulin resistance, LXA4 may exert anti-inflammatory effects and alleviate hepatic steatosis. Both lipid mediators derive from the same pathway, in which arachidonate 5-lipoxygenase (ALOX5) and its partner, arachidonate 5-lipoxygenase-activating protein (ALOX5AP), are involved. ALOX5 and ALOX5AP expression is increased in humans and rodents with obesity and insulin resistance. We found that transgenic mice overexpressing ALOX5AP in adipose tissue had higher LXA4 rather than higher LTB4 levels, were leaner, and showed increased energy expenditure, partly due to browning of white adipose tissue (WAT). Upregulation of hepatic LXR and Cyp7a1 led to higher bile acid synthesis, which may have contributed to increased thermogenesis. In addition, transgenic mice were protected against diet-induced obesity, insulin resistance, and inflammation. Finally, treatment of C57BL/6J mice with LXA4, which showed browning of WAT, strongly suggests that LXA4 is responsible for the transgenic mice phenotype. Thus, our data support that LXA4 may hold great potential for the future development of therapeutic strategies for obesity and related diseases.


Asunto(s)
Proteínas Activadoras de la 5-Lipooxigenasa/genética , Proteínas Activadoras de la 5-Lipooxigenasa/metabolismo , Tejido Adiposo/metabolismo , Expresión Génica , Resistencia a la Insulina/genética , Lipoxinas/metabolismo , Obesidad/genética , Tejido Adiposo Blanco/metabolismo , Animales , Dieta Alta en Grasa/efectos adversos , Células Hep G2 , Humanos , Resistencia a la Insulina/fisiología , Leucotrieno B4/metabolismo , Ratones , Ratones Transgénicos , Obesidad/etiología , Obesidad/metabolismo , Obesidad/prevención & control , Termogénesis/genética , Termogénesis/fisiología
8.
Plant Physiol Biochem ; 102: 133-40, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26934102

RESUMEN

Seed germination and dormancy are tightly regulated by hormone metabolism and signaling pathway. We investigated the endogenous content of abscisic acid (ABA), its catabolites, and gibberellins (GAs), as well as the expression level of certain ABA and GAs metabolic and signaling genes in embryo of dry and imbibed cypselas of inbred sunflower (Helianthus annuus L., Asteraceae) lines: B123 (dormant) and B91 (non-dormant). Under our experimental conditions, the expression of RGL2 gene might be related to the ABA peak in B123 line at 3 h of imbibition. Indeed, RGL2 transcripts are absent in dry and early embedded cypselas of the non-dormant line B91. ABA increase was accompanied by a significant ABA-Glucosyl ester (ABA-GE) and phaseic acid (PA) (two ABA catabolites) decrease in B123 line (3 h) which indicates that ABA metabolism seems to be more active in this line, and that it would be involved in the imposition and maintenance of sunflower seed dormancy, as it has been reported for many species. Finally, an increase of bioactive GAs (GA1 and GA3) occurs at 12 h of imbibition in both lines after a decrease in ABA content. This study shows the first report about the RGL2 tissue-specific gene expression in sunflower inbred lines with contrasting dormancy level. Furthermore, our results provide evidence that ABA and GAs content and differential expression of metabolism and signaling genes would be interacting in seed dormancy regulation through a mechanism of action related to embryo itself.


Asunto(s)
Regulación de la Expresión Génica de las Plantas/fisiología , Helianthus/metabolismo , Endogamia , Latencia en las Plantas/fisiología , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Helianthus/genética , Proteínas de Plantas/genética , Factores de Transcripción/genética
9.
J Biol Chem ; 290(27): 16772-85, 2015 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-25971976

RESUMEN

The human insulin-like growth factor 2 (IGF2) and insulin genes are located within the same genomic region. Although human genomic studies have demonstrated associations between diabetes and the insulin/IGF2 locus or the IGF2 mRNA-binding protein 2 (IGF2BP2), the role of IGF2 in diabetes pathogenesis is not fully understood. We previously described that transgenic mice overexpressing IGF2 specifically in ß-cells (Tg-IGF2) develop a pre-diabetic state. Here, we characterized the effects of IGF2 on ß-cell functionality. Overexpression of IGF2 led to ß-cell dedifferentiation and endoplasmic reticulum stress causing islet dysfunction in vivo. Both adenovirus-mediated overexpression of IGF2 and treatment of adult wild-type islets with recombinant IGF2 in vitro further confirmed the direct implication of IGF2 on ß-cell dysfunction. Treatment of Tg-IGF2 mice with subdiabetogenic doses of streptozotocin or crossing these mice with a transgenic model of islet lymphocytic infiltration promoted the development of overt diabetes, suggesting that IGF2 makes islets more susceptible to ß-cell damage and immune attack. These results indicate that increased local levels of IGF2 in pancreatic islets may predispose to the onset of diabetes. This study unravels an unprecedented role of IGF2 on ß-cells function.


Asunto(s)
Diabetes Mellitus/genética , Factor II del Crecimiento Similar a la Insulina/genética , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Animales , Desdiferenciación Celular , Línea Celular Tumoral , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatología , Humanos , Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Ratas
10.
Hum Mol Genet ; 24(7): 2078-95, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25524704

RESUMEN

Gene therapy is an attractive tool for the treatment of monogenic disorders, in particular for lysosomal storage diseases (LSD) caused by deficiencies in secretable lysosomal enzymes in which neither full restoration of normal enzymatic activity nor transduction of all affected cells are necessary. However, some LSD such as Mucopolysaccharidosis Type IIIB (MPSIIIB) are challenging because the disease's main target organ is the brain and enzymes do not efficiently cross the blood-brain barrier even if present at very high concentration in circulation. To overcome these limitations, we delivered AAV9 vectors encoding for α-N-acetylglucosaminidase (NAGLU) to the Cerebrospinal Fluid (CSF) of MPSIIIB mice with the disease already detectable at biochemical, histological and functional level. Restoration of enzymatic activity in Central Nervous System (CNS) resulted in normalization of glycosaminoglycan content and lysosomal physiology, resolved neuroinflammation and restored the pattern of gene expression in brain similar to that of healthy animals. Additionally, transduction of the liver due to passage of vectors to the circulation led to whole-body disease correction. Treated animals also showed reversal of behavioural deficits and extended lifespan. Importantly, when the levels of enzymatic activity were monitored in the CSF of dogs following administration of canine NAGLU-coding vectors to animals that were either naïve or had pre-existing immunity against AAV9, similar levels of activity were achieved, suggesting that CNS efficacy would not be compromised in patients seropositive for AAV9. Our studies provide a strong rationale for the clinical development of this novel therapeutic approach as the treatment for MPSIIIB.


Asunto(s)
Acetilglucosaminidasa/genética , Terapia Genética/métodos , Mucopolisacaridosis III/genética , Mucopolisacaridosis III/terapia , Acetilglucosaminidasa/líquido cefalorraquídeo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Dependovirus/genética , Dependovirus/metabolismo , Femenino , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Mucopolisacaridosis III/líquido cefalorraquídeo , Mucopolisacaridosis III/enzimología
11.
J Agric Food Chem ; 61(47): 11243-9, 2013 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-24188169

RESUMEN

Silicon has been extensively researched in relation to the response of plants to biotic and abiotic stress, as an element triggering defense mechanisms which activate the antioxidant system. Furthermore, in some species, adding silicon to unstressed plants modifies the activity of certain antioxidant enzymes participating in detoxifying processes. Thus, in this study, we analyzed the activity of antioxidant enzymes in leaves and roots of unstressed cotton plants fertilized with silicon (Si). Cotton plants were grown in hydroponic culture and added with increasing doses of potassium silicate; then, the enzymatic activity of catalase (CAT), guaiacol peroxidase (GPOX), ascorbate peroxidase (APX), and lipid peroxidation were determined. Using multivariate analysis, we found that silicon altered the activity of GPOX, APX, and CAT in roots and leaves of unstressed cotton plants, whereas lipid peroxidation was not affected. The analysis of these four variables in concert showed a clear differentiation among Si treatments. We observed that enzymatic activities in leaves and roots changed as silicon concentration increased, to stabilize at 100 and 200 mg Si L(-1) treatments in leaves and roots, respectively. Those alterations would allow a new biochemical status that could be partially responsible for the beneficial effects of silicon. This study might contribute to adjust the silicon application doses for optimal fertilization, preventing potential toxic effects and unnecessary cost.


Asunto(s)
Antioxidantes/metabolismo , Enzimas/metabolismo , Gossypium/efectos de los fármacos , Gossypium/metabolismo , Silicio/farmacología , Ascorbato Peroxidasas/metabolismo , Catalasa/metabolismo , Hidroponía , Peroxidación de Lípido/efectos de los fármacos , Análisis Multivariante , Peroxidasa/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/enzimología , Raíces de Plantas/metabolismo , Estrés Fisiológico
12.
J Clin Invest ; 123(8): 3254-3271, 2013 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-23863627

RESUMEN

For most lysosomal storage diseases (LSDs) affecting the CNS, there is currently no cure. The BBB, which limits the bioavailability of drugs administered systemically, and the short half-life of lysosomal enzymes, hamper the development of effective therapies. Mucopolysaccharidosis type IIIA (MPS IIIA) is an autosomic recessive LSD caused by a deficiency in sulfamidase, a sulfatase involved in the stepwise degradation of glycosaminoglycan (GAG) heparan sulfate. Here, we demonstrate that intracerebrospinal fluid (intra-CSF) administration of serotype 9 adenoassociated viral vectors (AAV9s) encoding sulfamidase corrects both CNS and somatic pathology in MPS IIIA mice. Following vector administration, enzymatic activity increased throughout the brain and in serum, leading to whole body correction of GAG accumulation and lysosomal pathology, normalization of behavioral deficits, and prolonged survival. To test this strategy in a larger animal, we treated beagle dogs using intracisternal or intracerebroventricular delivery. Administration of sulfamidase-encoding AAV9 resulted in transgenic expression throughout the CNS and liver and increased sulfamidase activity in CSF. High-titer serum antibodies against AAV9 only partially blocked CSF-mediated gene transfer to the brains of dogs. Consistently, anti-AAV antibody titers were lower in CSF than in serum collected from healthy and MPS IIIA-affected children. These results support the clinical translation of this approach for the treatment of MPS IIIA and other LSDs with CNS involvement.

13.
Plant Cell Environ ; 36(3): 569-78, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22897345

RESUMEN

Ozone (O(3) ) is an air pollutant with an impact increasingly important in our industrialized world. It affects human health and productivity in various crops. We provide the evidences that treatment of Arabidopsis thaliana with O(3) results in ascorbate-derived oxalic acid production. Using cultured cells of A. thaliana as a model, here we further showed that oxalic acid induces activation of anion channels that trigger depolarization of the cell, increase in cytosolic Ca(2+) concentration, generation of reactive oxygen species and cell death. We confirmed that O(3) reacts with ascorbate in the culture, thus resulting in production of oxalic acid and this could be part of the O(3) -induced signalling pathways that trigger programmed cell death.


Asunto(s)
Arabidopsis/metabolismo , Ácido Oxálico/metabolismo , Ozono/metabolismo , Transducción de Señal , Contaminantes Atmosféricos/metabolismo , Aniones/metabolismo , Arabidopsis/citología , Ácido Ascórbico/metabolismo , Calcio/metabolismo , Muerte Celular , Células Cultivadas , Citoplasma/metabolismo , Especies Reactivas de Oxígeno/metabolismo
14.
Plant Cell Environ ; 31(6): 842-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18266898

RESUMEN

Aerial parts of plants curve towards the light (i.e. positive phototropism), and roots typically grow away from the light (i.e. negative phototropism). In addition, Arabidopsis roots exhibit positive phototropism relative to red light (RL), and this response is mediated by phytochromes A and B (phyA and phyB). Upon light stimulation, phyA and phyB interact with the phytochrome kinase substrate (PKS1) in the cytoplasm. In this study, we investigated the role of PKS1, along with phyA and phyB, in the positive phototropic responses to RL in roots. Using a high-resolution feedback system, we studied the phenotypic responses of roots of phyA, phyB, pks1, phyA pks1 and phyB pks1 null mutants as well as the PKS1-overexpressing line in response to RL. PKS1 emerged as an intermediary in the signalling pathways and appears to promote a negative curvature to RL in roots. In addition, phyA and phyB were both essential for a positive response to RL and act in a complementary fashion. However, either photoreceptor acting without the other results in negative curvature in response to red illumination so that the mode of action differs depending on whether phyA and phyB act independently or together. Our results suggest that PKS1 is part of a signalling pathway independent of phyA and phyB and that PKS1 modulates RL-based root phototropism.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Luz , Fosfoproteínas/metabolismo , Fototropismo/fisiología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana , Mutación , Fosfoproteínas/genética , Fitocromo A/metabolismo , Fitocromo B/metabolismo , Factores de Tiempo
15.
J Exp Bot ; 57(12): 3217-29, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908503

RESUMEN

Red light, acting through the phytochromes, controls numerous aspects of plant development. Many of the signal transduction elements downstream of the phytochromes have been identified in the aerial portions of the plant; however, very few elements in red-light signalling have been identified specifically for roots. Gene profiling studies using microarrays and quantitative Real-Time PCR were performed to characterize gene expression changes in roots of Arabidopsis seedlings exposed to 1 h of red light. Several factors acting downstream of phytochromes in red-light signalling in roots were identified. Some of the genes found to be differentially expressed in this study have already been characterized in the red-light-signalling pathway for whole plants. For example, PHYTOCHROME KINASE 1 (PKS1), LONG HYPOCOTYL 5 (HY5), EARLY FLOWERING 4 (ELF4), and GIGANTEA (GI) were all significantly up-regulated in roots of seedlings exposed to 1 h of red light. The up-regulation of SUPPRESSOR OF PHYTOCHROME A RESPONSES 1 (SPA1) and CONSTITUTIVE PHOTOMORPHOGENIC 1-like (COP1-like) genes suggests that the PHYA-mediated pathway was attenuated by red light. In addition, genes involved in lateral root and root hair formation, root plastid development, phenylpropanoid metabolism, and hormone signalling were also regulated by exposure to red light. Interestingly, members of the RPT2/NPH3 (ROOT PHOTOTROPIC 2/NON PHOTOTROPIC HYPOCOTYL 3) family, which have been shown to mediate blue-light-induced phototropism, were also differentially regulated in roots in red light. Therefore, these results suggest that red and blue light pathways interact in roots of seedlings and that many elements involved in red-light-signalling found in the aerial portions of the plant are differentially expressed in roots within 1 h of red light exposure.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Luz , Transducción de Señal/genética , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Arabidopsis/metabolismo , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/genética , Cloroplastos/genética , Cloroplastos/metabolismo , Perfilación de la Expresión Génica , Modelos Biológicos , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenilalanina/metabolismo , Fitocromo B/genética , Fitocromo B/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de la radiación , Plastidios/genética , Plastidios/metabolismo , Reacción en Cadena de la Polimerasa
16.
Mol Ther ; 13(2): 401-10, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16271515

RESUMEN

Phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32) is the rate-controlling enzyme in gluconeogenesis. In diabetic individuals, altered rates of gluconeogenesis are responsible for increased hepatic glucose output and sustained hyperglycemia. Liver-specific inhibition of PEPCK has not been assessed to date as a treatment for diabetes. We have designed a therapeutic, vector-based RNAi approach to induce posttranscriptional gene silencing of hepatic PEPCK using nonviral gene delivery. A transient reduction of PEPCK enzymatic activity (7.6 +/- 0.6 vs 9.7 +/- 1.1 mU/mg, P < 0.05) that correlated with decreased protein content of up to 50% was achieved using this strategy in diabetic mice. PEPCK partial silencing was sufficient to demonstrate lowered blood glucose (218 +/- 26 vs 364 +/- 33 mg/dl, P < 0.001) and improved glucose tolerance together with decreased circulating FFA (0.89 +/- 0.10 vs 1.44 +/- 0.11 mEq/dl, P < 0.001) and TAG (65 +/- 11 vs 102 +/- 16 mg/dl, P < 0.01), in the absence of liver steatosis or lactic acidosis. SREBP1c was down-regulated in PEPCK-silenced animals, suggesting a role for this pathway in the alterations of lipid metabolism. These data reinforce the significance of PEPCK in sustaining diabetes-induced hyperglycemia and validate liver-specific intervention at the level of PEPCK for diabetes gene therapy.


Asunto(s)
Diabetes Mellitus Experimental/terapia , Marcación de Gen , Hiperglucemia/terapia , Hígado/enzimología , Fosfoenolpiruvato Carboxiquinasa (GTP)/antagonistas & inhibidores , Fosfoenolpiruvato Carboxiquinasa (GTP)/genética , Interferencia de ARN , Animales , Línea Celular Tumoral , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/enzimología , Silenciador del Gen , Marcación de Gen/métodos , Técnicas de Transferencia de Gen , Humanos , Hiperglucemia/enzimología , Hiperglucemia/etiología , Interferones/fisiología , Masculino , Ratones , Ratones Endogámicos ICR , Fosfoenolpiruvato Carboxiquinasa (GTP)/administración & dosificación , eIF-2 Quinasa/fisiología
17.
Asunción; s.n; 2000. 143 p. tab, graf. (PY).
Tesis en Español, Inglés | LILACS, PARAGUAY | ID: biblio-1018388

RESUMEN

Estudio descriptivo de carácter cuali-cuantitativo con una muestra de 53 pacientes que reingresaron al Sanatorio Juan Max Boettner. Presenta el perfil de los enfermos que por abandono o interrupción de su tratamiento regresan al hospital originandose nuevas reacciones y se buscan estrategias de solución. Describe el impacto de esta enfermedad en la sociedad y sus connotaciones


Asunto(s)
Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/dietoterapia , Tuberculosis Pulmonar/patología , Tuberculosis Pulmonar/prevención & control , Tuberculosis/diagnóstico , Tuberculosis/dietoterapia , Tuberculosis/patología
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