Expresión y purificación de GDNF para su microencapsulación y aplicación en la enfermedad de Parkinson

La enfermedad de Parkinosn (EP) es un proceso neurodegenerativo del sistema nervioso central que afecta a las neuronas de dopamina de la sustancia negra, núcleo mesoencefálico del control motor. La perdida en el cerebro de este neurotransmisor vital causa los síntomas de la enfermedad. La EP afecta actualmente a 200 de cada 100.000 personas y a 2 de cada 100 entre los mayores de 60 años. En España hay unos 110.000 enfermos. Además, hoy por hoy no se conoce nada que pueda prevenir o curar la enfermedad, ni existe ninguna prueba de laboratorio que permita diagnosticarla. Recentiemente se ha demostrado que el GDNF, factor neurotrófico derivado de las células gliales, es capaz de proteger las neuronas dopaminérgicas e incluso inducir la regeneración del tejido dopaminérgico dañado in vivo. El objetivo del trabajo fue diseñar y desarrolar un método de expresión y purificación de GDNF bioactivo para su posterior microencapsulación y aplicación en la enfermedad de Parkison. El sistema escogido para expresar el GDNF fue el sistema de células eucariotas de mamífero. El vector utilizado para la producción del GDNF en células eucariotas fue el pDEST26 (Tecnología Gateway de Invitrogen). Como sistema de expresión de GDNF se utilizaron las líneas celulares eucariota BHK, 293 y COS 7. Estas células fueron cultivadas en medio D-MEM (Invitrogen) complementado con un 10% de suero fetal bovino (FBS) y Penicilina/Streptomicina (100u/ml) (Invitrogen). La transfección se realizó con Lipofectamine Plus (Invitrogen). Se analizó la expresión de GDNF a nivel de mRNA mediante PCR y a nivel de proteína mediante Western Blot del medio condicionado. Los clones positivos se crecieron en botellas de cultivo de 850 cm2 (Corning) y se realizaron ciclos de recolección del medio. Cada ciclo fue analizado por SDS-PAGE y Western Blot. Para evaluar la actividad de la proteína se ha desarrollado un ensayo de actividad en el que se demuestra la diferenciación morfológica de células PC-12 inducida por GDNF. La presencia de los receptores GFRa1 y RET, necesarios para que el GDNF ejerza su acción, fue determinada por PCR. Las conclusiones obtenidas de este estudio son la obtención de GDNF recombinante a partir de un sistema de expresión en células eucariotas, el desarrollo de un protocolo para su posterior purificación y la obtención de GDNF recombinante biológicamente activo

Microencapsulación de factores neurotróficos: aplicación al tratamiento de la enfermedad de Parkinson

La enfermedad de Parkinson (EP) es una enfermedad degenerativa, lentamente progresiva caracterizada por temblor de reposo, cara inexpresiva, rigidez, lentitud al iniciar y practicar movimientos voluntarios. Neuropatológicamente se caracteriza por pérdida de células dopaminérgicas en la sustancia nigra lo cual conlleva déficit en el suministro de dopamina a nivel de ganglios basales. Los factores de crecimiento nervioso, o factores neurotróficos, que respaldan la supervivencia, crecimiento y desarrollo de las células cerebrales, son un tipo de terapia prometedora para la enfermedad de Parkinson. Se ha demostrado que el GDNF, factor neurotrófico derivado de la línea celular glial, protege las neuronas de dopamina y promueve su supervivencia en los modelos animales de la enfermedad de Parkinson. Sin embargo, la administración de proteínas en el cerebro no está exenta de dificultades, por ello, el sistema elegido para administrar el GDNF en el cerebro será uno de los puntos clave para el éxito del tratamiento. En este sentido, el uso de micropartículas formuladas a partir de polímeros biodegradables parece ser la estrategia más apropia. En nuestro grupo de investigación hemos desarrollado un protocolo de expresión y purificación de GDNF en células eucariótas de mamífero. El objetivo de este estudio es la microencapsulación de la proteína en partículas biodegradables

Terapias neuroprotectoras y neurorestauradoras en el tratamiento de la enfermedad de Parkinson

Parkinson's disease is the second most common neurodegenerative disorder after Alzheimer's disease. Current therapies are symptomatic and, although these therapies are efficacious during the early stages of the disease, they present important side effects when they are used for a long time. The ideal therapy would be the one that would slow down or stop the progression of the disease. This can be achieved, for instance, with neuroprotective and neurorestorative therapies. Among them, cell therapy and therapy with trophic factors such as glial cell line derived neurotrophic factor (GDNF) are the most challenging and promising ones for the scientific community. Although the use of GDNF as a treatment for Parkinson s disease was proposed several years ago, it is necessary to develop alternative strategies to deliver GDNF appropriately to concrete areas of the brain. Here, the use of microspheres as the most suitable tool for the administration of this neurotrophic factor is discussed

Long-term neuroprotection and neurorestoration by glial cell-derived neurotrophic factor microspheres for the treatment of parkinson's disease

BACKGROUND: Glial cell-derived neurotrophic factor is a survival factor for dopaminergic neurons and a promising candidate for the treatment of Parkinson's disease. However, the delivery issue of the protein to the brain still remains unsolved. Our aim was to investigate the effect of long-term delivery of encapsulated glial cell-derived neurotrophic factor within microspheres. METHODS: A single dose of microspheres containing 2.5 μg of glial cell-derived neurotrophic factor was implanted intrastriatally in animals 2 weeks after a 6-hydroxydopamine lesion. RESULTS: The amphetamine test showed a complete behavioral recovery after 16 weeks of treatment, which was maintained until the end of the study (week 30). This effect was accompanied by an increase in dopaminergic striatal terminals and neuroprotection of dopaminergic neurons. CONCLUSIONS: The main achievement was the long-term neurorestoration in parkinsonian animals induced by encapsulated glial cell-derived neurotrophic factor, suggesting that microspheres may be considered as a means to deliver glial cell-derived neurotrophic factor for Parkinson's disease treatment. © 2011 Movement Disorder Society

Production of highly pure human glycosylated GDNF in a mammalian cell line

The administration of glial cell line-derived neurotrophic factor (GDNF) has emerged as a promising strategy for the treatment of several diseases of the nervous system as Parkinson's disease, amyotrophic lateral sclerosis, spinal cord injury and nerve regeneration as well as ocular diseases and drug addictions. A procedure for the purification of human recombinant glycosylated GDNF using a mammalian expression system as the source of the protein is discussed in the present paper. The neurotrophic factor was purified using cation exchange chromatography and gel filtration. A human cell line was chosen as the source of therapeutic protein, since a recombinant protein with a structure and glycosylation pattern equivalent to the native form is desirable for its prospective therapeutic utilization. The activity of the highly pure protein obtained was confirmed with a cell-based bioassay. The purified protein is suitable for its in vivo evaluation in animals and for possible subsequent clinical application

Sustained release of bioactive glycosylated glial cell-line derived neurotrophic factor from biodegradable polymeric microspheres

Glial cell line-derived neurotrophic factor (GDNF), a potent neurotrophic factor for dopaminergic neurons, appeared as a promising candidate for treating Parkinson's disease. GDNF microencapsulation could ensure protection against degradation due to the fragile nature of the protein. Poly(lactide-co-glycolide) (PLGA) microparticles loaded with recombinant glycosylated GDNF obtained in a mammalian cell line were prepared by TROMS, a semi-industrial technique capable of encapsulating fragile molecules maintaining their native properties. The effects of several parameters as PLGA copolymer type, PEG 400 quantity co-encapsulated with GDNF or drug loading, on the properties of the particles were investigated. Microparticles showed a mean diameter between 8 and 30 μm, compatible with their stereotaxic implantation. The drug entrapment efficiency ranged from 50.6 to 100% depending on the microsphere composition. GDNF was better encapsulated using hydrophilic polymers with high molecular weight such as RG 503H. In vitro drug release was influenced by the polymer type as well as by the amount of PEG 400 co-encapsulated with GDNF. Microparticles prepared using PLGA RG 503H released 67% of the total protein content within 40 days. Moreover, very low concentrations of poly (vinyl alcohol) were detected after microparticles washing and freeze-drying. Finally, a PC-12 bioassay demonstrated that the in vitro GDNF released was bioactive

Effective GDNF brain delivery using microspheres-A promising strategy for Parkinson’s disease

Glial cell line-derived neurotrophic factor (GDNF) has shown promise in the treatment of neurodegenerative disorders of basal ganglia origin such us Parkinson's disease (PD). In this study, we investigated the neurorestorative effect of controlled GDNF delivery using biodegradable microspheres in an animal model with partial dopaminergic lesion. Microspheres were loaded with N-glycosylated recombinant GDNF and prepared using the Total Recirculation One-Machine System (TROMS). GDNF-loaded microparticles were unilaterally injected into the rat striatum by stereotaxic surgery two weeks after a unilateral partial 6-OHDA nigrostriatal lesion. Animals were tested for amphetamine-induced rotational asymmetry at different times and were sacrificed two months after microsphere implantation for immunohistochemical analysis. The putative presence of serum IgG antibodies against rat glycosylated GDNF was analyzed for addressing safety issues. The results demonstrated that GDNF-loaded microspheres, improved the rotational behavior induced by amphetamine of the GDNF-treated animals together with an increase in the density of TH positive fibers at the striatal level. The developed GDNF-loaded microparticles proved to be suitable to release biologically active GDNF over up to 5 weeks in vivo. Furthermore, none of the animals developed antibodies against GDNF demonstrating the safety of glycosylated GDNF use

Revista de Vertebrados de la Estación Biológica de Doñana

Página 298 con error de impresiónEstudio cariológico en dos especies de Serránidos del Mediterráneo (Peces: PerciformesRelaciones morfométricas de Atherina boyeri Risso (Pisces: Atherinidae) de la laguna de Zoñar (Córdoba, España)Contribución al conocimiento de la biometríay osteología de Barbus barbus bocagei, Steindachner, 1866 (Pisces: CyprinidaeLa actividad de la salamandra, Salamandra salamandra (L.), en Galicia.Estudios sobre el sapo corredor (Bufo calamita) en el Sur de España.1. BiometríaEstudios sobre el sapo corredor (Bufo calamita) en el Sur de España. II. AlimentaciónBiología de la reproducción de Rana iberica Boulenger 1879 en zonas simpátridas con Rana temporaria Linneo, 1758Nuevos datos sobre la distribución geográfica de Lacerta monticola cantabrica Mertens, 1929. (Sauria, lacertidae).Datos sobre Lacerta monticola Boulenger, 1905 (Saurio: lacertidae)en el oeste del Sistema Central.Nueva especie de Anolis (lacertilia, Iguanidae) para CubaEtograma cuantificado del cortejo en Falco naumannOntogénesis del comportamiento predador en Falco naumanniContaminación xenobiótica del Parque Nacional de Doñana. 1. Residuos de insecticidas organoclorados, bifenilos policlorados y mercurio en anseriformes y gruiformesReproducción del críalo (Clamator glandarius) en Sierra Morena CentraNidificación de Picus viridis en taludes de arcilla en Ramblas de Guadix (Granada)Comportamiento del calamón Porphyrio porphyrio (Linnaeus, 1758) en Doñana, Marismas del GuadalquiviBiología y ecología de la malvasía (Oxyura leucocephala) en Andalucía.On the differential diet of Carnivora in islands:a method for analysing it and a particular case.Notas sobre la distribución pasada y actual del meloncillo Herpestes ichneumon (L.) en la Península IbéricaEstructuración de las interacciones en una camada de lobos (Canís lupus)Nuevos datos sobre la distribución del Cottus gobio L. (pisces, cottidae) en EspañaSobre la alimentación de Callopistes maculatus (Reptilia,teiidaeObservación de Lacerta lepida depredando un nido de Alectoris rufaNueva cita del galápago leproso Mauremys leprosa (Scheigger, 1812) en los pirineosPrimera cita de Psammodromus hispanicus (Fitzinger) para GaliciaSobre la presencia de Gallotia (=Lacerta) atlantica (Peters y Doria, 1882) en Gran CanariaNota sobre las Lacerta monticola Boulenger, 1905 de las zonas del norte de GaliciaPrimeras notas herpetológicas de la provincia de Soria.Datos sobre selección de hábitat y ecología alimenticia del porrón pardo (Aythya nyroca)Probable nueva área de cría del pechiazul (Luscinia svecica cyanecula) en el sistema central. PerisPredación de Falco peregrinus y Falco subbuteo sobre quirópterosResultados de la producción de Oxyura leucocephala en el año 1981 en las lagunas de Zóñar y el rincónAnálisis de la dieta de Tyto alba en un medio árido antropógeno de los alrededores de Almería¿Son Eudocimus ruber y E. albus distintas especies?EL Estornino pinto (Sturnus vulgaris) en Canarias: nueva especie nidifiante en el archipiélagoDatos sobre la alimentación otoñal del cárabo (Strix aluco) en la sierra de CádizObservación primaveral de rapaces y otras aves en el páramo del estado de Mérida (Venezuela).Murciélago hematófago (Desmodus rotundus) parasitando a un chigüire (Hidrochoerus hydrochaeris)Observaciones sobre la reproducción del zacatuche o teporinho Romerolagus diazi (Mammalia: lagomorpha)Estudio electroforético de hemoglobinas y esterasas sanguíneas en Rhinolophus ferrumequinum (Chiroptera: rhinolophidae) y de hemoglobinas en Tadaria taeniotis (chiroptera: molossidae)Peer reviewe

Risk factors for non-diabetic renal disease in diabetic patients

Background. Diabetic patients with kidney disease have a high prevalence of non-diabetic renal disease (NDRD). Renal and patient survival regarding the diagnosis of diabetic nephropathy (DN) or NDRD have not been widely studied. The aim of our study is to evaluate the prevalence of NDRD in patients with diabetes and to determine the capacity of clinical and analytical data in the prediction of NDRD. In addition, we will study renal and patient prognosis according to the renal biopsy findings in patients with diabetes. Methods. Retrospective multicentre observational study of renal biopsies performed in patients with diabetes from 2002 to 2014. Results. In total, 832 patients were included: 621 men (74.6%), mean age of 61.7 6 12.8 years, creatinine was 2.8 6 2.2 mg/dL and proteinuria 2.7 (interquartile range: 1.2–5.4) g/24 h. About 39.5% (n ¼ 329) of patients had DN, 49.6% (n ¼ 413) NDRD and 10.8% (n ¼ 90) mixed forms. The most frequent NDRD was nephroangiosclerosis (NAS) (n ¼ 87, 9.3%). In the multivariate logistic regression analysis, older age [odds ratio (OR) ¼ 1.03, 95% CI: 1.02–1.05, P < 0.001], microhaematuria (OR ¼ 1.51, 95% CI: 1.03–2.21, P ¼ 0.033) and absence of diabetic retinopathy (DR) (OR ¼ 0.28, 95% CI: 0.19–0.42, P < 0.001) were independently associated with NDRD. Kaplan–Meier analysis showed that patients with DN or mixed forms presented worse renal prognosis than NDRD (P < 0.001) and higher mortality (P ¼ 0.029). In multivariate Cox analyses, older age (P < 0.001), higher serum creatinine (P < 0.001), higher proteinuria (P < 0.001), DR (P ¼ 0.007) and DN (P < 0.001) were independent risk factors for renal replacement therapy. In addition, older age (P < 0.001), peripheral vascular disease (P ¼ 0.002), higher creatinine (P ¼ 0.01) and DN (P ¼ 0.015) were independent risk factors for mortality. Conclusions. The most frequent cause of NDRD is NAS. Elderly patients with microhaematuria and the absence of DR are the ones at risk for NDRD. Patients with DN presented worse renal prognosis and higher mortality than those with NDRD. These results suggest that in some patients with diabetes, kidney biopsy may be useful for an accurate renal diagnosis and subsequently treatment and prognosis

Association of candidate gene polymorphisms with chronic kidney disease : Results of a case-control analysis in the NEFRONA cohort

Chronic kidney disease (CKD) is a major risk factor for end-stage renal disease, cardiovascular disease and premature death. Despite classical clinical risk factors for CKD and some genetic risk factors have been identified, the residual risk observed in prediction models is still high. Therefore, new risk factors need to be identified in order to better predict the risk of CKD in the population. Here, we analyzed the genetic association of 79 SNPs of proteins associated with mineral metabolism disturbances with CKD in a cohort that includes 2,445 CKD cases and 559 controls. Genotyping was performed with matrix assisted laser desorption ionization-time of flight mass spectrometry. We used logistic regression models considering different genetic inheritance models to assess the association of the SNPs with the prevalence of CKD, adjusting for known risk factors. Eight SNPs (rs1126616, rs35068180, rs2238135, rs1800247, rs385564, rs4236, rs2248359, and rs1564858) were associated with CKD even after adjusting by sex, age and race. A model containing five of these SNPs (rs1126616, rs35068180, rs1800247, rs4236, and rs2248359), diabetes and hypertension showed better performance than models considering only clinical risk factors, significantly increasing the area under the curve of the model without polymorphisms. Furthermore, one of the SNPs (the rs2248359) showed an interaction with hypertension, being the risk genotype affecting only hypertensive patients. We conclude that 5 SNPs related to proteins implicated in mineral metabolism disturbances (Osteopontin, osteocalcin, matrix gla protein, matrix metalloprotease 3 and 24 hydroxylase) are associated to an increased risk of suffering CKD