[Evaluation of the survival of bone marrow mononucleate cells transplanted in a rat model of striatal lesion with quinolinic acid]. / Evaluacion de la supervivencia de las células mononucleadas de la médula ósea trasplantadas en un modelo de ratas con lesión estriatal por ácido quinolínico.

INTRODUCTION: Transplant is one of the alternatives available for the treatment of neurodegenerative diseases aimed at replacing the cells lost during the course of the disease. One promising source of cells for the development of transplants could be the mononucleate cells from bone marrow. AIMS. The purpose of this study was to study the capacity of bone marrow mononucleate cells to survive the transplant process, and to search for a method that enables tracking of these cells in vivo once they have been implanted. MATERIALS AND METHODS: Bone marrow mononucleate cells were extracted from the femur of rats by means of a Ficoll-Hypaque gradient. The cells under study were modified genetically with an adenovirus that expresses the PFV or which are marked with Hoechst dye. The marked cells were implanted in the striatum of rats with lesions caused by quinolinic acid. RESULTS: The viability of the genetically modified cells was low, whereas that of the cells marked with Hoechst dye was above 90%. The implanted cells survived the transplant at least a month and dispersed away from the site of entry towards the corpus callosum and cortex. CONCLUSIONS: We consider that the use of Hoechst dye offers more advantages for tracking these cells in vivo. Mononucleate cells have a number of characteristics that allow them to be included as candidate sources of cells for the treatment of neurodegenerative diseases.

[Survival of dopaminergic neurons that were hibernated in vitro for seven days]. / Supervivencia in vitro de neuronas dopaminérgicas hibernadas durante siete días.

INTRODUCTION: The use of fresh foetal tissue in neurotransplants entails considerable problems of logistics that limit its clinical applicability, something that can be resolved by the development of optimal tissue storage procedures that do not affect in vivo viability and survival of dopamine. AIMS. To determine whether 7 days' hibernation affects the survival of mesencephalic tissue in vitro, and to compare it to fresh tissue. MATERIALS AND METHODS: The midbrains of rats were hibernated for 1, 3, 5 and 7 days at 4 degrees C. A cellular suspension was prepared for culture throughout a 7-day period. The number of TH+ cells present in the fresh and hibernated cultures was determined. RESULTS: The morphology of the hibernated and cultured dopaminergic neurons was very similar to that of the fresh cells. Comparing the viability of the hibernated and fresh cells did not reveal any significant differences. No significant differences between the numbers of TH+ neurons were observed at any of the hibernation times. The lowest rate of TH+ cell survival was reached at seven days' hibernation. Significant differences (p < 0.05) were found between the number of TH+ neurons for fresh and hibernated tissue. CONCLUSIONS: Hibernation at 4 degrees C for up to five days guarantees the survival of TH+ cells in vitro, but it is affected by longer times. This procedure could be considered useful for preserving human tissue in clinical transplant applications. These results refer to in vitro conditions; therefore, studies must be conducted to investigate the survival and functionality of hibernated and transplanted neurons in animal models to enable us to evaluate its applicability in neurorestorative therapy.

[Marrow stromal cells cultured in N2-supplemented medium: implications on the generation of neural cells]. / Cultivo de las células estromales de la médula ósea en un medio suplementado con los nutrientes N2: implicaciones sobre la generación de células neurales.

INTRODUCTION: Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20% fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs. AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0.5 and 1% using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate. MATERIALS AND METHODS: Stromal cells isolated from rat femurs were cultivated in Dulbecco's modified Eagle medium at 10, 1, 0.5% FBS or in serum free medium containing N2 formula. In serum free medium or at low serum concentration culture surface was coated with PLL. Cell survival was determined by MTT method or by counting viable cells. RESULTS: Survival of MSCs cultured in N2 supplement was reduced at about 40% of that observed in 10% FBS containing medium. Under these conditions cell morphology was also affected. When N2 containing medium was supplemented with FBS at 0.5 or 1% a significant increase of survival with respect to that observed in N2-supplemented cultures was observed. Cells seeded on PLL-coated surface increased their survival by contrast with their homologous cultures seeded on uncoated surface. CONCLUSIONS: The culture system which combines N2 formula with FBS 1% and PLL-coated surface is useful for the maintenance of MSCs. These conditions offer advantages for the study of differentiation of these cells because they reduce the confounding influence of serum. The possible implication of this culture system for the study of neural differentiation by these cells is discussed.

[Stromal cell transplant in the 6-OHDA lesion model]. / Trasplante de células estromales en el modelo de lesión por 6-OHDA.

INTRODUCTION: A good deal of evidence currently exists to show that transplanting foetal mesencephalic tissue can produce symptomatic benefits both in patients and in disease models. Nevertheless, the technical and ethical difficulties involved in obtaining enough suitable foetal cerebral tissue have been a serious obstacle to its application. Stromal cells derived from bone marrow, due to their potential capacity to generate different types of cells, could be an ideal source of material for cell restoration in neurodegenerative diseases. AIMS: Our aim was to evaluate the effect of transplanting stromal cells derived from bone marrow on the behaviour of 6-OHDA rats, when they are inserted into the striatum. MATERIAL AND METHODS: In this study we used rats with a lesion in the substantia nigra induced by 6-hydroxydopamine, divided into several experimental groups. Rotary activity induced by D-amphetamine (5 mg/kg, intraperitoneally) was evaluated before and throughout the three months following the transplant in all the experimental groups, except in the group of healthy controls. Hemiparkinsonian rats received a total of 350 000 foetal ventral mesencephalic cells and 8 x 10(4) stromal cells/microL, which were implanted in the striatum. RESULTS AND CONCLUSIONS: Animals with stromal cells transplanted in the body of the striatum significantly reduced the number of turns induced by amphetamine (p < 0.05); yet this reduction was not greater than that induced by foetal mesencephalic cell transplants. We were also unable to demonstrate any significant improvement in the motor skills of the forelimbs.

Trasplante de células estromales en el modelo de lesión por 6-OHDA / Stromal cell transplant in the 6-OHDA lesion model

A good deal of evidence currently exists to show that transplanting foetal mesencephalic tissue can produce symptomatic benefits both in patients and in disease models. Nevertheless, the technical and ethical difficulties involved in obtaining enough suitable foetal cerebral tissue have been a serious obstacle to its application. Stromal cells derived from bone marrow, due to their potential capacity to generate different types of cells, could be an ideal source of material for cell restoration in neurodegenerative diseases. AIMS: Our aim was to evaluate the effect of transplanting stromal cells derived from bone marrow on the behaviour of 6-OHDA rats, when they are inserted into the striatum(AU)

[In vitro viability and glutathione levels in mesencephalic neurons after seven days hibernation]. / Viabilidad in vitro y niveles de glutati n en neuronas mesencef licas hibernadas durante siete d as.

In embryonic mesencephalic transplant in patients with Parkinson s disease dopaminergic survival is low (5 10%), and for this reason the use of multiple donors has been considered. The difficulty of obtaining more tissue determines the need for a procedure that enables human nigral tissue to be stored for a time without affecting its physiological state in any significant way. This study was designed to determine whether hibernation of tissue fragments has any influence on viability, how the viability of the mesencephalic cells behaves after 7 days hibernation and the glutathione levels in the hibernated tissue (HT). The viability of the HT in pieces (82.37 2.12) was found to be higher than the value for the whole mesencephalon (70.29 3.43). Viability of the HT, seven days at 4 C, at different post dissociation times, did not differ significantly. Despite the significant differences found between hibernated and fresh tissue at t= 0, this procedure does not seem to affect the mesencephalic tissue in any significant way, as it conserved a 94% viability after hibernation. No evidence was found of increased glutathione content as an antioxidizing response to the damage that might be caused by hibernation. These results suggest that since hibernation does not have any significant effect on the state of the cells it could be considered a useful procedure for conserving tissue to be used in clinical transplants. Moreover, further research is needed on survival and functionality of hibernated cells after being transplanted into animal models in order to evaluate their potential for use in cell therapy.

[Effects of simultaneous transplant of foetal mesencephalic cells in the striatum and the subthalamic nucleus of hemiparkinsonian rats]. / Efectos del trasplante simultáneo de células mesencefálicas fetales en el estriado y el núcleo subtalámico de ratas hemiparkinsonianas.

INTRODUCTION: The main strategy followed in neural transplants as a method of treatment for Parkinson s disease, both experimental and clinical, has been to introduce foetal mesencephalic cells into the target area: the striatum. However, when the dopaminergic cells in the substantia nigra degenerate, not only is the dopaminergic innervation of the striatum affected but also other nuclei: globus pallidus, substantia nigra, substantia nigra pars reticulata and subthalamic nucleus. A series of data from pharmacological and physiological studies offer strong evidence that the dopamine released in these nuclei may play an important role in regulating the output nuclei of the basal ganglia. AIM: To evaluate the effect of transplanting foetal mesencephalic cells on the behaviour of 6 OH DA rats when introduced into the striatum and the subthalamic nucleus. MATERIALS AND METHODS: 6 OH DA was used to induce lesions in the substantia nigra of rats, which were divided into several experimental groups. The rotating activity induced by D amphetamine (5 mg/kg, intraperitoneally) and apomorphine (0.05 mg/kg, subcutaneously) was evaluated before and three months after the transplant in all the experimental groups, except in the control group of healthy rats. The hemiparkinsonian rats received a total of 350,000 foetal ventral mesencephalic cells, which were implanted within small deposits in the striatum (8) and in the subthalamic nucleus (4). RESULTS AND CONCLUSIONS: Rotation induced by both drugs was significantly lower (p= 0.05) in animals that had had dopaminergic cells transplanted into the striatum body. No significant improvement in this behaviour was to be found when transplants were limited to just the subthalamus or, simultaneously, also to the striatum. A significant increase in rotating behaviour induced by apomorphine was observed in the group which received a transplant in just the subthalamus.

Purification and characterization of murine beta-nerve growth factor.

Beta-nerve growth factor (beta-NGF) is a trophic factor in the nervous system. We aimed to isolate and characterize this protein in view of its potential therapeutic use in neurodegenerative diseases. For purification a two-step ion-exchange procedure was followed. The characterization was performed using separation and immunological techniques, as well as a biological assay. These studies showed that the obtained protein consisted of a mixture of beta-NGF molecules, intact at their NH2-terminal extreme, and molecules which have lost the NH2-terminal octapeptide and exhibit modifications increasing its hydrophobicity. All these molecular species were recognized immunologically and showed biological activity.

[Fetal nerve tissue, ethics and transplants]. / Tejido nervioso fetal, ética y trasplante.

INTRODUCTION: The moral-ethical problem of the use of human embryos as a source of cells for neurotransplants involves serious conflicts as to which tissues to use, from which source, what method should be used to obtain them and also the search for alternative sources of tissues. DEVELOPMENT: In this paper we present a brief summary of ethical and medical points involved in the obtention, protection of the donor, preparation, safety and efficacy of human foetal nervous tissue in the context of neural transplants. The ethics of human foetal nervous tissue are very complex in that they represent a dilemma involving several points of medical ethics, which are themselves very controversial, including abortion, transplants and incorporation in the cerebral function of an individual. From a bioethical point of view, we consider aspects such as the establishment of an optimal source for obtention of nervous tissue for transplants, the safety and efficacy of this, informed consent for donation of tissue, availability and storage among other aspects. CONCLUSIONS: All programmes that envisage the use of foetal tissue for the purpose of transplants should strictly and truly conform to local and national ethical regulations before starting clinical trials.

[The obtaining of neural cell suspensions. Their application in neurobiological studies]. / Obtención de suspensiones de células neurales. Aplicación en las investigaciones neurobiológicas.

INTRODUCTION: Techniques of intracranial grafting have become powerful tools used in the study of the mechanisms of regeneration and plasticity taking place in the central nervous system (CNS). Suspensions of foetal neural cells have been successfully used as intracerebral grafts in deep regions of the brain. OBJECTIVE: The objective of this paper is to describe the methodology used by our group to obtain and prepare suspensions of cells from different parts of rat embryo brain (midbrain, striatum and septum) used for experimental transplants in animal models. MATERIAL AND METHODS: We give a detailed description of the steps involved in the preparation of tissue in the form of a suspension of cells. These steps include the obtention of tissue at the optimum stage of development, dissection of the donor tissue, enzymatic treatment and mechanical dissociation until a suspension of cells is obtained. Viability counts showed a high percentage (more than 95%) of viable cells in the suspensions thus obtained. Cellular viability is affected by different factors and is a prerequisite for good survival of the graft. CONCLUSION: The methodology described permits obtention of suspensions of foetal neural cells which are optimal for use in studies both in vitro and in experimental transplants.

[The action of epidermal growth factor on the development of cultured striatum cells]. / Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales en cultivo.

INTRODUCTION: Epidermic growth factor (EGF) has a neurotrophic mitogenic effect on different cell populations in the nervous system. This is modulated by the stage of development and microenvironment of the cells. OBJECTIVE AND METHODS: In this paper we describe the action of EGF on embryonic striatum cells of a culture system dissociated from neurons and glias. The cell culture is prepared from 16-17 day rat embryos. In the system used, the cell population was cultured for 20-24 hours in a medium containing serum. This medium was later replaced by a mixture of specific nutrients and treated for 6 days with 20 mg/ml of EGF. RESULTS AND CONCLUSIONS: The substitution of serum during the initial period of development led to an appreciable reduction in the living cells in the treated cultures and in the controls. The surviving cells were mainly cellular precursors, taking into account their morphological characteristics and capacity for proliferation. The effect of EGF was seen in an increase in the number of cells and was shown to be a stimulus to the proliferation of neuronal and astrocyte precursors. The specific activity of choline acetyl-transferases determined in the cultures at 16 days showed differentiation of a cholinergic neurons subpopulation, which responded to treatment with nerve growth factor with an increase in the activity of this enzyme.

Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales en cultivo / Action of the epidermal growth factor on the development of striatal cell culture

Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)

Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales en cultivo / Action of the epidermal growth factor on the development of striatal cell culture

Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)

Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales en cultivo / Action of the epidermal growth factor on the development of striatal cell culture

Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima (AU)

Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales en cultivo / Action of the epidermal growth factor on the development of striatal cell culture

Introducción. El factor de crecimiento epidérmico (FCE) ejerce un efecto neurotrófico o mitogénico sobre diferentes poblaciones celulares en el sistema nervioso, lo que está modulado por el estadío de desarrollo celular y el microambiente donde se desarrollan las células. Objetivo y métodos. En este trabajo se describe la acción del FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glias. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema empleado la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y posteriormente se sutituyó este por una mezcla de nutrientes definidos y se trató con 20 ng/ml de FCE durante 6 días. Resultados y conclusiones. La sustitución del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Las células sobrevivientes estaban representadas mayoritariamente por precursores celulares teniendo en cuenta sus características morfológicas y su capacidad proliferativa. El efecto del FCE se manifestó en un aumento del número de células y se demostró un estímulo de la proliferación de los precursores neuronales y de los astrocitos. La actividad específica de la colina acetiltransferasa determinada en los cultivos a los 16 días evidenció la diferenciación de una subpoblación neuronal colinérgica, la cual respondió al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de esta enzima