[Changes in nerve growth factor levels related to age and neurotrophic treatment in non-human primate]. / Cambios en los niveles de factor de crecimiento nervioso con el envejecimiento y el tratamiento neurotrófico en primates no humanos.

INTRODUCTION: To examine the amounts and role of growth factors in different tissues and corporal fluid, new sensitive techniques have to be developed. A major problem is that the normal concentration of trophic substances, such as nerve growth factor (NGF), in central and peripheral nervous system and in fluids is very low (ng pg/ml). A valuable method of research is the sensitive two site enzyme immunoassay using the monoclonal antibody 27/21 to mouse NGF. Materials and methods. The present work applied this enzyme immunoassay to examine the NGF levels in normal non human primate sera (n= 94) and applied this assay to study of NGF levels in two non human primate receiving NGF infusion: one young and one aged. Two groups of non human primate sera were studied one young adult (n= 69) and one aged (n= 25). The serum samples NGF treated non human primate were taken before the infusion and at the 1st week and 1st, 3rd, 6th and 12th month after infusion. RESULTS: To further test the specificity of conjugate binding, dilutions of the non human primate sera were preincubated with an excess of monoclonal NGF antibody 27/21 in solution. With this strategy it was possible to completely block the signal obtained using the enzyme immunoassay. We found very low levels of NGF in aged monkeys (0.054 ng/ml) when compared with young adult group (0.152 ng/ml) (p> 0.01). The NGF levels in aged non human primate treatment with NGF was very low before (0.50 ng/ml) and during NGF treatment evolution time, whereas at the the 12th month showed an increase in NGF levels (0.180 ng/ml). We found normal values of NGF in the young monkey before and during the first year after NGF infusion. CONCLUSIONS: Using the enzyme immunoassay described it is possible to know the serum concentration of NGF immunoreactive in non human primate and this assay is able to detect peripheral changes in NGF levels after intracerebral infusion of NGF.

Indicadores del metabolismo oxidativo en primates no humanos viejos / Levels oxidative metabolism markers during aging in non-human primates

En condiciones fisiológicas las células aeróbicas producen cantidades de Especies Reactivas de Oxígeno. La supervivencia celular depende del balance entre los procesos oxidativos y las defensas antioxidantes. Esta interacción determina si la célula se encuentra en estrés oxidativo o no. Recientes estudios sugieren que una reducida capacidad en el metabolismo oxidativo así como estados proinflamatorios contribuyen a cambios neurodegenerativos relacionados con la edad en los humanos. Por tal motivo en el presente estudio nosotros comparamos los niveles séricos de la actividad de la superóxido dismutasa (SOD), Catalasa (CAT) y también los niveles de malonildialdehido (MDA) y el factor de necrosis tumoral a (TNFa) en primates no humanos jóvenes y viejos. Nuestros resultados sugieren relación entre las alteraciones del metabolismo oxidativo con los cambios neurodegenerativos que ocurren en los monos.

[A study of the oxidative stress indicators in elderly monkeys]. / Estudio de indicadores de estrés oxidativo en monos viejos.

INTRODUCTION: Under physiological conditions aerobic cells produce reactive species of oxygen. Cell survival depends on the equilibrium between the oxidation processes and the antioxidant defences. This interaction determines whether the cell suffers oxidation stress or not. Recent studies suggest that a reduced capacity for oxidation metabolism and proinflammatory states contribute to neurodegenerative changes related to age in humans. OBJECTIVE: To obtain information regarding the relation of TNF-mu to oxidation phenomena in nonhuman primates. MATERIAL AND METHODS: In this study we compare serum levels of the activity of superoxide dismutase (SOD) catalase (CAT), the levels of malonyldialdehyde (MDA) and tumor necrosis factor alpha TNF-alpha using spectrophotometric techniques in young and old nonhuman primates. RESULTS AND CONCLUSION: Our results suggest a relationship between the alterations in oxidation metabolism with the neurodegenerative changes which occur in monkeys.

[Nerve growth factor and neurological diseases]. / Factor de crecimiento nervioso y enfermedades neurológicas.

INTRODUCTION: The effects of Nerve Growth Factor (NGF) within and outside the nervous system have been amply discussed in recent decades. Recently clinical studies have shown the effectiveness of this growth factor in the treatment of neurodegenerative disorders. This clinical use makes it necessary to have sensitive, specific methods available to permit measurement of the level of this protein and to determine how it behaves during the course of treatment. OBJECTIVE: To describe the measurement of NGF levels in human serum using an immunoenzymatic method and evaluating the levels of this protein in some neurological disorders. Materials and methods. NGF levels were measured in the serum of healthy persons and in patients with Alzheimer's disease (AD) Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS) and Huntington's chorea (HC) using a double site immune-enzymatic assay. Murine 27/21 anti-beta-NGF monoclonal antibody was used as the antibody to cover the plate and as conjugate. RESULTS: Adding a block pass to the method, in which the sample was incubated with an excess of 27/21 antibody effectively reduced the signal observed in the immuno-enzymatic assay. A moderate reduction in beta-NGF levels was seen in the serum of patients with ALS and MS. There was a statistically significant reduction in the patients who were carriers of PD and HC. CONCLUSIONS: The significant reduction in NGF levels in patients with PD and HC may be associated with a disorder in the use of this protein in central and peripheral tissues.

Factor de crecimiento nervioso y enfermedades neurológicas / Nerve growth factor and neurological diseases

Introducción. Los efectos del factor de crecimiento nervioso (NGF, Nerve Growth Factor) dentro y fuera del sistema nervioso son ampliamente discutidos en las últimas décadas. Recientemente algunos estudios clínicos han demostrado la efectividad de este factor de crecimiento como tratamiento en enfermedades neurodegenerativas. Este uso clínico va necesariamente aparejado con la necesidad de contar con métodos sensibles y específicos que permitan cuantificar los niveles de esta proteina y conocer cómo se comportan los mismos durante la evolución del tratamiento. Objetivo. Describir la cuantificación del NGF en suero humano mediante el empleo de un método inmunoenzimático y evaluar los niveles de esta proteina en algunas enfermedades neurológicas. Material y métodos. Los niveles de NGF fueron cuantificados en suero de pacientes sanos y de pacientes con enfermedad de Alzheimer (EA), enfermedad de Parkinson (EP), esclerosis lateral amiotrófica (ELA), esclerosis múltiple (EM) y corea de Huntington (CH) mediante la utilización de un ensayo inmunoenzimático de doble sitio. Se utilizó el anticuerpo monoclonal anti B-NGF 27/21 murino como anticuerpo recubridor de la placa y como conjugado. Resultados. La adición al método de un paso de bloqueo, donde se incuba la muestra con un exceso de anticuerpo 27/21, redujo de manera efectiva la señal observada en el ensayo inmunoenzimático. Se evidenció una disminución moderada en los niveles de B-NGF en suero de pacientes con ELA y EM, y una disminución estadísticamente significativa en los pacientes portadores de EP y CH. Conclusiones. La disminución significativa en los niveles de NGF en pacientes con EP y CH puede estar relacionada con una alteración en la utilización de esta proteina en tejidos centrales o periféricos

[Neuronal toxicity of human recombinant interleukin-2 in rats. Morphological and behavioral validation]. / Toxicidad neuronal de la interleucina-2 recombinante humana en ratas. Validación morfoconductual.

INTRODUCTION AND OBJECTIVE: The memory impairment which accompanies the aging process is a manifestation of diminished cognitive function. This is intimately related to neuropathological and biochemical changes in cholinergic areas of central nervous system (CNS). Cytokines, first described as immunoregulators, are also implied in defense reactions of the brain. Some studies on the action of IL-2 on the CNS suggest an action blocking the release of acetylcholine in the hippocampus. MATERIAL AND METHODS: We have studied the possible central neurotoxic effect of this soluble factor using the chronic intraperitoneal infusion of human recombinant IL-2 (hr-IL 2) to young and old Sprague Dawley rats. RESULTS AND CONCLUSIONS: The results do not show an in vivo action of IL-2 on the cholinergic function but are consistent with the probable role of this cytokine in the senescent cognitive impairment, in particular the age-related loss of spatial memory and/or during the evolution of neurodegenerative related process.

Toxicidad neuronal de la interleucina-2 recombinante humana en ratas: validación morfoconductual / Neuronal toxicity of human recombinant interleukin 2 in rats: morphoconductual validation

Introducción y objetivo. La afectación de memoria que se observa en el envejecimiento es una manifestación de la disminución de las funciones cognitivas con la edad, la cual está estrechamente asociada a cambios neuropatológicos y bioquímicos en áreas colinérgicas del sistema nervioso central (SNC). Las citoquinas, descritas por primera vez como moléculas inmunoreguladoras, están también implicadas en reacciones defensivas del cerebro. Estudios relacionados con la acción de la IL-2 sobre el SNC le atribuyen un efecto bloqueador sobre la secreción de acetilcolina a nivel hipocampal. Material y métodos. Hemos desarrollado un estudio dirigido a caracterizar los efectos neurotóxicos centrales de esta citoquina mediante la infusión crónica intraperitoneal de IL-2 recombinante humana (IL-2rh) en ratas jóvenes y viejas de la línea Sprague Dawley. Resultados y conclusiones. Los resultados obtenidos, aunque parciales, no parecen referir el posible efecto in vivo de la IL-2 sobre la función colinérgica central, pero si son consistentes con la implicación probable de esta citoquina en el deterioro cognitivo senescente y, de manera particular, en el deterioro de la memoria espacial asociada a la edad y/o en el curso de trastornos neurodegenerativos relacionados

Evolutive levels of NGF in neurodegenerative disorders

The two-site enzyme immunoassasy (EIA) using the monoclonal antibody (MAb) 27/21 is a valuable method capable of detecting mouse and human NGF quantitatively (Soderstrom et al., 1990). The presence of NGF in serum has been controversial, since t6he previous assay methods failed to detect circulating NGF. Recently, we described the immunological detection of low levels of NGF in human serum samples and introduced a blocking test validating the specificity of the immunoreactivity for NGF in human serum (Lorigados et al., 1982). In the present work, we applied this two-site EIA using monoclonal NGF antibody 27/21 in the study of NGF serum levels from diverse neurodegenerative disorders. We also studied evolutive samples of Parkinson's patients that received neural transplant