Overexpression of kynurenic acid in stroke: An endogenous neuroprotector?

It is known that kynurenic acid (KYNA) exerts a neuroprotective effect against the neuronal loss induced by ischemia; acting as a scavenger, and exerting antioxidant action. In order to study the distribution of KYNA, a highly specific monoclonal antibody directed against KYNA was developed. This distribution was studied in control rats and in animals in which a middle cerebral artery occlusion (stroke model) was induced. By double immunohistochemistry, astrocytes containing KYNA and GFAP were exclusively found in the ipsilateral cerebral cortex and/or striatum, at 2, 5 and 21days after the induction of stroke. In control animals and in the contralateral side of the stroke animals, no immunoreactivity for KYNA was found. Under pathological conditions, the presence of KYNA is reported for the first time in the mammalian brain from early phases of stroke. The distribution of KYNA matches perfectly with the infarcted regions suggesting that, in stroke, this overexpressed molecule could be involved in neuroprotective/scavenger/antioxidant mechanisms.

3-hydroxi-anthranilic acid is early expressed in stroke

Using an immunohistochemical technique, we have studied the distribution of 3-OH-anthranilic acid (3-HAA) in the rat brain. Our study was carried out in control animals and in rats in which a stroke model (single transient middle cerebral artery occlusion) was performed. A monoclonal antibody directed against 3-HAA was also developed. 3-HAA was exclusively observed in the infarcted regions (ipsilateral striatum/cerebral cortex), 2, 5 and 21 days after the induction of stroke. In control rats and in the contralateral side of the stroke animals, no immunoreactivity for 3-HAA was visualized. Under pathological conditions (from early phases of stroke), we reported for the first time the presence of 3-HAA in the mammalian brain. By double immunohistochemistry, the coexistence of 3-HAA and GFAP was observed in astrocytes. The distribution of 3-HAA matched perfectly with the infarcted regions. Our findings suggest that, in stroke, 3-HAA could be involved in the tissue damage observed in the infarcted regions, since it is well known that 3-HAA exerts cytotoxic effects.

NO-tryptophan: a new small molecule located in the rat brain

A highly specific monoclonal antibody directed against nitric oxide-tryptophan (NO-W) with good affinity (10-9 M) and specificity was developed. In the rat brain, using an indirect immunoperoxidase technique, cell bodies containing NO-W were exclusively found in the intermediate and dorsal parts of the lateral septal nucleus. No immunoreactive fibres were found in the rat brain. This work reports the first visualization and the morphological characteristics of cell bodies containing NO-W in the mammalian brain. The restricted distribution of NO-W in the rat brain suggests that this molecule could be involved in specific physiological mechanisms.

Direct visualization of retinoic acid in the rat hypothalamus: an immunohistochemical study

In order to increase our knowledge about the distribution of vitamins in the mammalian brain, we have developed a highly specific antiserum directed against retinoic acid with good affinity (10(-8) M), as evaluated by ELISA tests. In the rat brain, no immunoreactive fibers containing retinoic acid were detected. Cell bodies containing retinoic acid were only found in the hypothalamus. This work reports the first visualization and the morphological characteristics of cell bodies containing retinoic acid in the mammalian paraventricular hypothalamic nucleus and in the dorsal perifornical region, using an indirect immunoperoxidase technique. The restricted distribution of retinoic acid in the rat brain suggests that this vitamin could be involved in very specific physiological mechanisms.

Mapping of somatostatin-28 (1-12) in the alpaca diencephalon

Using an immunocytochemical technique, we report for the first time the distribution of immunoreactive cell bodies and fibers containing somatostatin-28 (1-12) in the alpaca diencephalon. Somatostatin-28 (1-12)-immunoreactive cell bodies were only observed in the hypothalamus (lateral hypothalamic area, arcuate nucleus and ventromedial hypothalamic nucleus). However, immunoreactive fibers were widely distributed throughout the thalamus and hypothalamus. A high density of such fibers was observed in the central medial thalamic nucleus, laterodorsal thalamic nucleus, lateral habenular nucleus, mediodorsal thalamic nucleus, paraventricular thalamic nucleus, reuniens thalamic nucleus, rhomboid thalamic nucleus, subparafascicular thalamic nucleus, anterior hypothalamic area, arcuate nucleus, dorsal hypothalamic area, around the fornix, lateral hypothalamic area, lateral mammilary nucleus, posterior hypothalamic nucleus, paraventricular hypothalamic nucleus, suprachiasmatic nucleus, supraoptic hypothalamic nucleus, and in the ventromedial hypothalamic nucleus. The widespread distribution of somatostatin-28 (1-12) in the thalamus and hypothalamus of the alpaca suggests that the neuropeptide could be involved in many physiological actions.

Circulating Antibodies to IDO/THO Pathway Metabolites in Alzheimer's Disease

In Alzheimer's disease, indoleamine 2,3-dioxygenase and tryptophan hydroxylase are known to induce an overproduction of neurotoxic compounds, such as quinolinic acid and 3-hydroxykynurenine from the former, and 5-hydroxytryptophol and 5-methoxytryptophol from the latter. Other compounds, such as kynurenic acid, serotonin, and melatonin are produced via the same pathways. An improved ELISA method identified circulating antibodies directed against these compounds, linked to proteins, as previously described for other chronic diseases. This describes how only the A isotype of circulating immunoglobulins recognized a pattern of conjugated tryptophan metabolites in the sera of Alzheimer patients. These data indirectly confirmed the involvement of tryptophan derivatives in the pathogenic processes of Alzheimer's disease. Further studies are required to evaluate the relevance of these antibody patterns in monitoring this disease.

Evaluation of the effects of a new drug candidate (GEMSP) in a chronic EAE model

Chronic Experimental Autoimmune Encephalomyelitis (EAE) was induced in rats to evaluate a new drug candidate (GEMSP) for the treatment of multiple sclerosis. This work is a part of preclinical studies on GEMSP, which is made up of fatty acids, vitamins and amino acids or their derivatives; all these compounds were linked to Poly-L-Lysine. In order to evaluate the effects of GEMSP, animals were divided into three experimental groups: 1) EAE rats treated with GEMSP; 2) EAE rats treated with NaCl; and 3) non-EAE rats. Using immunocytochemical techniques with a pan-leukocyte marker (anti-CD 45), differential leukocyte infiltration was compared in the central nervous systems of the different experimental groups. Antibodies directed against a component of GEMSP, the conjugated methionine, were used in all three groups. We found that: 1) GEMSP was effective in abolishing EAE. The crises and clinical scores were completely abolished in the animals of the first group, but not in the animals belonging to the second group; 2) the degree of leukocyte infiltration varied, depending on the different EAE stages, but was not related to the clinical score; and 3) after using anti-conjugated methionine antibodies, we observed immunoreactivity only in the motoneurons of the ventral horn of the spinal cord in the animals of the first group. This immunoreactivity was not found in the animals of the second or third groups. No methionine immunoreactivity was found in the brain. Our results suggest that GEMSP may be a potential drug candidate against the pathogenic processes involved in multiple sclerosis, inhibiting EAE episodes and brain leukocyte infiltration. Our results also show that one component of GEMSP, the methionine compound, is stored inside motoneurons. The possible physiological actions of GEMSP on spinal cord motoneurons are discussed.

Immunocytochemical visualization of d-glutamate in the rat brain

Using highly specific antisera directed against conjugated d-amino acids, the distribution of d-glutamate-, d-tryptophan-, d-cysteine-, d-tyrosine- and d-methionine-immunoreactive structures in the rat brain was studied. Cell bodies containing d-glutamate, but not d-glutamate-immunoreactive fibers, were found. Perikarya containing this d-amino acid were only found in the mesencephalon and thalamus of the rat CNS. Thus, the highest density of cell bodies containing d-glutamate was observed in the dorsal raphe nucleus, the ventral part of the mesencephalic central gray, the superior colliculus, above the posterior commissure, and in the subparafascicular thalamic nucleus. A moderate density of immunoreactive cell bodies was observed in the dorsal part of the mesencephalic central gray, above the rostral linear nucleus of the raphe, the nucleus of Darkschewitsch, and in the medial habenular nucleus, whereas a low density was found below the medial forebrain bundle and in the posterior thalamic nuclear group. Moreover, no immunoreactive fibers or cell bodies were visualized containing d-tryptophan, d-cysteine, d-tyrosine or d-methionine in the rat brain. The distribution of d-glutamate-immunoreactive cell bodies in the rat brain suggests that this d-amino acid could be involved in several physiological mechanisms. This work reports the first visualization and the morphological characteristics of conjugated d-glutamate-immunoreactive cell bodies in the rat CNS using an indirect immunoperoxidase technique. Our results suggest that the immunoreactive neurons observed have an uptake mechanism for d-glutamate.

Thiamine-like fibers in the monkey brain: an immunocytochemical study

The distribution of thiamine-immunoreactive structures was studied in the brain of the monkey using an indirect immunoperoxidase technique. Fibers containing thiamine, but no thiamine-immunoreactive cell bodies, were found. The highest density of fibers containing thiamine was observed in the pulvinar nucleus and in the region extending from the pulvinar nucleus to the caudate nucleus. In the mesencephalon, immunoreactive fibers containing thiamine were only found at rostral level close to the medial lemniscus (at the mesencephalic-diencephalic junction). In the thalamus, the distribution of thiamine-immunoreactive structures was more widespread. Thus, immunoreactive fibers were found in nuclei close to the midline (centrum medianum/parafascicular complex), in the ventrolateral thalamus (medial geniculate nucleus, inferior pulvinar nucleus), and in the dorsolateral thalamus (lateral posterior nucleus, pulvinar nucleus). Finally, in the anterior commissure and in the cerebral cortex a low density immunoreactive fibers was visualized. Thus, in the brainstem, no immunoreactive structures were visualized in the medulla oblongata, pons, or in the medial-caudal mesencephalon, and no immunoreactive fibers were observed in the cerebellum, hypothalamus and in the basal ganglia. The present report describes the first visualization and the morphological characteristics (thick, smooth and short, medium or long in length) of the thiamine-immunoreactive fibers in the primate central nervous system using an antiserum directed against this vitamin. The distribution of thiamine-immunoreactive structures in the monkey brain suggests that this vitamin could be involved in several physiological mechanisms.

Riboflavin-like inmunoreactive fibers in the monkey brain

Using an antiserum directed against the vitamin riboflavin, we studied the distribution of riboflavin-like immunoreactive structures in the monkey brain. In the mesencephalon, at the level of the mesencephalic-diencephalic junction, single riboflavin-like immunoreactive fibers were observed in its dorsal part, whereas a low density of immunoreactive fibers was found below the surface of the section and close to substantia nigra, and a high density was observed above the substantia nigra and close to the medial geniculate nucleus. In the thalamus, single riboflavin-like immunoreactive fibers were found in the ventral regions of the lateral posterior and the medial geniculate nuclei; a low density in the region located above the medial and lateral geniculate nuclei and a high density in the ventral part of the pulvinar nucleus and in the region extending from this latter to the caudate nucleus. Immunoreactive fibers were not observed in the medulla oblongata, pons, cerebellum, hypothalamus, basal ganglia and cerebral cortex. Moreover, no riboflavin-like immunoreactive cell bodies were observed in the monkey brain. The distribution of riboflavin-like immunoreactive fibers in the monkey suggests that this vitamin could be involved in several physiological mechanisms.

Folic acid in the monkey brain: an immunocytochemical study

The present report describes the first visualization of folic acid-immunoreactive fibers in the mammalian central nervous system using a highly specific antiserum directed against this vitamin. The distribution of folic acid-immunoreactive structures was studied in the brainstem and thalamus of the monkey using an indirect immunoperoxidase technique. We observed fibers containing folic acid, but no folic acid-immunoreactive cell bodies were found. In the brainstem, no immunoreactive structures were visualized in the medulla oblongata, pons, or in the medial-caudal mesencephalon, since at this location immunoreactive fibers containing folic acid were only found at the rostral level in the dorsolateral mesencephalon (in the mesencephalic-diencephalic junction). In the thalamus, the distribution of folic acid-immunoreactive structures was more widespread. Thus, we found immunoreactive fibers in the midline, in nuclei close to the midline (dorsomedial nucleus, centrum medianum/parafascicular complex), in the ventral region of the thalamus (ventral posteroinferior nucleus, ventral posteromedial nucleus), in the ventrolateral thalamus (medial geniculate nucleus, lateral geniculate nucleus, inferior pulvinar nucleus) and in the dorsolateral thalamus (lateral posterior nucleus, pulvinar nucleus). The highest density of fibers containing folic acid was observed in the dorsolateral mesencephalon and in the pulvinar nucleus. The distribution of folic acid-immunoreactive structures in the monkey brain suggests that this vitamin could be involved in several mechanisms, such as visual, auditory, motor and somatosensorial functions.

[Surgical treatment of a pheocromocytoma bilateral in a 5 year old patient with the von Hippel-Lindau disease]

INTRODUCTION

The disease of Von Hippel Lindau (VHL) is hereditary and causes a predisposition to the development of tumours. Organs such as the cerebellum, the pancreas, the kidney, the suprarenal glands and the retina are more usually affected by this disease.

CLINICAL CASE

We present the case of a 5-year-old patient who suffers from asiymptomatic high blood pressure. In the family antecedents, it is relevant the case of the father, with pheocromocytoma bilateral, which led us to carry out a genetic study of his two sons. Our patient, the younger; presented a mutation of the VHL gene in the short arm of the chromosome 3. In one of the periodic controls, it could be detected high blood pressure of 160/100 mm. Hg, clinically asymptomatic. The other child did not present a genetic mutation and has no disease. The presence of high catecholamines, the detection of a 3 cm left suprarenal mass through the ecography, the TAC that did not show a right suprarenal pathology and the MBIG scintigraphy confirmed the diagnostic of pheocromocytoma. The RNM showed another 0.8-cm mass which confirmed a pheocromocytoma bilateral. We started the treatment against high blood pressure with fenoxibenzamine and diltiazem, and we controlled this problem. We also prepared the pre-and-post operation anesthetic strategy, which is so important for the surgical success. The operation started by a laparoscopic, we made left adrenalectomy and we had to reconvert to laparotomy to make partial right adrenalectomy. Six months after the operation, the patient is free from symptomatology and follows a treatment with glucocorticoides with smaller and smaller doses.

COMMENTS

The case is exceptional because it embodies the following characteristics: early diagnostic age, family affectation and discovery of asymptomatic high blood pressure. It needed an appropriate preanesthetic and anesthetic preparation, which gave way to an operation without complications. The postoperation was also stable and presented no complications.

Spanish children's diet: compliance with nutrient and food intake guidelines

OBJECTIVE

To compare the diet of Spanish children against the nutrient and food intake guidelines. To calculate an index of overall diet quality and check its validity against nutrient intake.

DESIGN AND SETTING

Cross-sectional study in four cities in Spain, where information on food and nutrient intake was obtained from schoolchildren through a food frequency questionnaire.

PARTICIPANTS

The sample included 1112 children (overall response rate of 85%) attending public and private schools and aged 6-7 y. Children were selected through random cluster sampling in schools, and stratified by sex and socioeconomic level.

MAIN OUTCOME MEASURES

Mean nutrient intake, number of food servings, and the percentage of children who meet recommended nutrient and food-serving intake levels. The overall dietary quality was assessed using the Healthy Eating Index (HEI).

RESULTS

Mean micronutrient intake exceeded 100% of the recommended dietary allowances, except for vitamin B6, which registered a mean intake of 77.1%. For almost all children, intake of saturated fat was above, and that of carbohydrate below, the recommended level, in contrast to the relatively high compliance with the recommendations for poly- and monounsaturated fatty acid, salt and fiber intake (69.7, 43.7, 40.7, and 30.1%, respectively). Consumption of food servings for each of the five American pyramid food groups came close to or exceeded USDA guidelines, with the exception of cereals, with 5.4 servings per day. The mean score obtained in the HEI was 64.6. Children who complied with all the food guide pyramid recommendations registered a higher dietary variety and a healthier nutritional profile.

CONCLUSIONS

Children aged 6-7 y show scant compliance with the macronutrient goals for healthy eating. Micronutrient intake is adequate in general, yet there are small groups of children with risk of deficient intake of vitamins B6 and D. While Spanish children's eating habits are reasonably in line with American food guide pyramid guidelines, consumptions of cereals and fruit should be improved.

[Effects of pharmacological doses of polyunsaturated fatty acids of the series 3 on the concentration of plasma lipoproteins]

Cardiovascular disease is one of the main causes of death in developed countries. Its incidence may be modified through dietary changes, this being supported by the low incidence of the disease among populations with high intake of fatty fishes. The aim of this work was to study the modifications on plasmatic levels of polyunsaturated fatty acids omega 3 after an additional supply of fish oils and to assess its effect on the metabolism of lipids and lipoproteins. The study was conducted on 8 healthy volunteers, their age ranging between 24 and 37 years. They received, during 30 days and in tablets of 500 mg, 7.5 gr/24 h of fish oil concentrate which supplied 2.5 gr/24 h of fatty acids omega 3. After 12 hours of fasting, blood samples were taken before and after the intake of this concentrate. Methyl esters from fatty acids omega 3 were assessed through gas chromatography; cholesterol, triglycerides, LDL, VLDL, HDLt, HDL2 and HDL3, through several enzymatic techniques; and lipoprotein(a) Lp(a), through ELISA. The statistical analysis was conducted using the Student's method for matched data. After 30 days of supplement, we observed: a significant increase in the plasmatic percentage of fatty acids omega 3 (EPA + DHA) along with a significant decrease of triglycerides, VLDL and HDL3 and a significant increase of HDL2, We did not observe any significant changes in cholesterol, LDL and HDLt. With respect to Lp(a), after one month of dietary supplement, its plasmatic levels did not change. Our results supports the clinical usefulness of the dietary supplementation with fatty acid omega 3 for the management of hypertriglyceridemias.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of dietary oil (olive/sunflower) on the plasmatic apolipoprotein profile]

FOUNDATIONS: The dietary oil provides a significant portion of the caloric intake in the form of fat, although there is some controversy with respect to the potential positive action of each type of oil. In this study, the effect on the lipo-apoprotein profile of monounsaturated fatty acids (MUFA) provided by olive oil and the polyunsaturated fatty acids (PUFA) provided by girasol oil are compared in a population with high risk of arteriosclerosis, as it is the aged population.

METHODOLOGY

44 aged patients living in the same institution, 21 males and 23 females (age: 79 +/- 6 years), and following two different diets during 3 months, with olive and girasol oils, respectively, participated in the study. Both diets were isocaloric: 2.300 kcal/day, 17% proteins, 33% lipids (30 g/day of oil), and 50% carbohydrates. Plasmatic concentrations of cholesterol (C), triglycerides (TG), c-LDL, c-VLDL, c-HDL2, c-HDL3 and lipoprotein a (Lp[a]), as well as apoproteins A1, B, CII, CIII and E, were assessed. Applied statistics: Student's t test for matched samples.

RESULTS

C and TG plasmatic levels did not changed, whereas levels of c-LDL decreased significantly, as well as levels of polyunsaturated fatty acids (135 +/- 43 and 124 +/- 33 mg/dl., p < 0.009) and levels of apo B (151 +/- 47 and 139 +/- 36 mg/dl., p < 0.009). Levels of c-HDL increased significantly (49 +/- 14 and 52 +/- 16 mg/dl., p < 0.01) as well as levels of apo A1 (190 +/- 32 and 205 +/- 41 mg/dl., p < 0.01). Levels of apo CIII (8.2 +/- 2.8 and 9.9 +/- 3.2 mg/dl., p < 0.008) and apo E (3.2 +/- 1.1 and 3.7 +/- 0.9 mg/dl., p < 0.01) also increased in men. Women did not showed any significant variations in lipoproteins, although apo A1 and apo E increased slightly and apo B decreased, although not significantly, with the polyunsaturated fat. The levels of Lp(a) did not changed.

CONCLUSIONS

In the aged population following a standard diet, without overloads, the PUFAs induced positive changes in the lipoapoprotein profile when compared to a previous diet with MUFA. Those changes were more evident in men than in women.

[Beta-thromboglobulin levels and atherosclerosis. Its relationship with the presence of risk factors]

In order to evaluate whether plasma beta-thromboglobulin (as a marker of the degree of platelet function) in patients presenting clinically evident atherosclerosis is related to the presence or absence of different risk factors (smoking habit, arterial hypertension, hypercholesterolemia, diabetes, hypertriglyceridemia, obesity, hyperuricemia, alcoholism), 40 patients have been studied in whom mean beta-thromboglobulin levels was 54 +/- 25.56 ng/ml, which is very superior to levels considered normal. However, the presence of one or more risk factors did not lead to significant variations in b-thromboglobulin concentrations, and no differences were found either when each risk factor was considered separately. The positive correlation (r = 0.98; p less than 0.01) between beta-thromboglobulin and apo B levels is highlighted. The results suggest that platelet hyperfunction seems to be due to a greater extent to the atherosclerotic process rather than to the existence of a particular risk factor.

Role of growth hormone-releasing hormone on pentagastrin-induced growth hormone release in normal subjects

In order to investigate the mechanisms by which gastrin cause GH release in humans we measured the GH response to pentagastrin alone (1.5 micrograms/kg/hour from 120 to 210 min) and following pretreatment with GHRH (GHRH 1-29,250 micrograms, iv at 0 min) in normal male subjects. Prior GHRH administration abolished the GH response to the second bolus of GHRH (1 micrograms/kg) administered two hours later. Pentagastrin infusion induced a rise in GH levels maximal at 60 min (9.1 + 0.6 ng/ml, mean + SE), but this rise was abolished by pretreatment with GHRH. Finally, we found that gastrin did not modify basal GH release or GH responses to GHRH by rat anterior pituitary cells in monolayer culture. Taken together, these data suggest that gastrin regulates GH secretion by acting at hypothalamic level.