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The intent of this study was to assess whether the effect of birth weight on later body composition is modified by Pro12Pro, Pro12Ala, and Ala12Ala genotypes of the peroxisome proliferator–activated receptor ?-2 (PPAR?-2) gene. The PPAR?-2 gene polymorphism was genotyped in 273 adolescents aged 13–18.5 y, born at term and whose birth weight was known. They were selected from a cross-sectional multicenter study conducted in five Spanish cities in 2000–2002. Body mass index (BMI) was calculated from weight and height measurements, and body composition and fat distribution were estimated from skinfold thickness. A total of 229 subjects (111 males and 118 females) carried the Pro12Pro genotype and 44 (22 males and 22 females) the Pro12Ala and Ala12Ala PPAR?-2 genotypes. In the Pro12Pro group, birth weight Z score was positively associated with both fat-free mass (FFM) (p < 0.05) and fat mass (FM) (p < 0.05), but these relationships disappeared after controlling for age, gestational age, socioeconomic status (SES), physical activity, Tanner stage, sex, and BMI. In the Ala12 group, birth weight Z score was positively associated with FFM (p < 0.01), and this relationship remained significant after controlling for confounding variables (p < 0.05). Small body weight at birth may program lower FFM in adolescents carrying the Ala12 allele in the PPAR?-2 gene.

The intent of this study was to assess whether the effect of birth weight on later body composition is modified by Pro12Pro, Pro12Ala, and Ala12Ala genotypes of the peroxisome proliferator–activated receptor -2 (PPAR-2) gene. The PPAR-2 gene polymorphism was genotyped in 273 adolescents aged 13–18.5 y, born at term and whose birth weight was known. They were selected from a cross-sectional multicenter study conducted in five Spanish cities in 2000–2002. Body mass index (BMI) was calculated from weight and height measurements, and body composition and fat distribution were estimated from skinfold thickness. A total of 229 subjects (111 males and 118 females) carried the Pro12Pro genotype and 44 (22 males and 22 females) the Pro12Ala and Ala12Ala PPAR-2 genotypes. In the Pro12Pro group, birth weight Zscore was positively associated with both fat-free mass (FFM) (p< 0.05) and fat mass (FM) (p< 0.05), but these relationships disappeared after controlling for age, gestational age, socioeconomic status (SES), physical activity, Tanner stage, sex, and BMI. In the Ala12 group, birth weight Zscore was positively associated with FFM (p< 0.01), and this relationship remained significant after controlling for confounding variables (p< 0.05). Small body weight at birth may program lower FFM in adolescents carrying the Ala12 allele in the PPAR-2 gene.

Estudiar si la actividad física realizada o el grado de condición física (capacidad aeróbica y fuerza) que poseen los adolescentes españoles, están asociados con su perfil lipídico-metabólico.

N-3 fatty acid deficiency has been related to decreased docosahexaenoic acid (DHA) and increased docosapentaenoic acid (DPA) levels in brain and to learning disadvantages. The influence of n-3 deficiency and supplementation on brain fatty acids and learning were investigated in young rats. Newborn Wistar rats were assigned to three groups of cross-foster mothers. The control group (C) was nursed by mothers that received essential fatty acids during pregnancy and lactation, and the deficient group (D) was nursed by mothers that did not receive those fatty acids. The supplemental group (S) had the same conditions as D, receiving an additional DHA and arachidonic acid supplement during lactation. Cerebral cortex and hippocampus fatty acid composition was examined using thin-layer and capillary column gas chromatography, and learning was measured by passive-avoidance procedure. D brains showed low DHA and high DPA levels, but S brain composition was similar to C. Learning in the S group was unaffected, but in the D group, it was poorer than C. Learning was directly correlated with DHA levels and inversely with DPA levels in brain. Low DHA and high DPA brain levels both were correlated with poor learning. DPA seems not to be a suitable brain functional analogue of DHA, and DHA supplementation reversed both biochemical and learning adverse effects observed in n-3 deficiency.

N-3 fatty acid deficiency has been related to decreased docosahexaenoic acid (DHA) and increased docosapentaenoic acid (DPA) levels in brain and to learning disadvantages. The influence of n-3 deficiency and supplementation on brain fatty acids and learning were investigated in young rats. Newborn Wistar rats were assigned to three groups of cross-foster mothers. The control group (C) was nursed by mothers that received essential fatty acids during pregnancy and lactation, and the deficient group (D) was nursed by mothers that did not receive those fatty acids. The supplemental group (S) had the same conditions as D, receiving an additional DHA and arachidonic acid supplement during lactation. Cerebral cortex and hippocampus fatty acid composition was examined using thin-layer and capillary column gas chromatography, and learning was measured by passive-avoidance procedure. D brains showed low DHA and high DPA levels, but S brain composition was similar to C. Learning in the S group was unaffected, but in the D group, it was poorer than C. Learning was directly correlated with DHA levels and inversely with DPA levels in brain. Low DHA and high DPA brain levels both were correlated with poor learning. DPA seems not to be a suitable brain functional analogue of DHA, and DHA supplementation reversed both biochemical and learning adverse effects observed in n-3 deficiency.

In vitro, cells derived from Ewing sarcoma (ES) with the characteristic somatic rearrangement between the genes EWS and FLI1 can be induced to differentiate toward a neuronal phenotype by exposure to agents such as dibutyryl cyclic AMP (db cAMP) or retinoic acid. Therefore, expression of the chimeric Ews-Fli1 protein does not irreversibly block the capacity of Ewing cells to engage in the neuronal differentiation program initiated by these agents. To identify genes that might be involved in the maintenance of Ewing cells in their undifferentiated state, a PCR-based differential display method was used to compare gene expression patterns in Ewing cell lines with those induced to differentiate toward a neuronal phenotype. A cDNA was expressed at high levels in proliferating Ewing-derived EW-1 cells and downregulated in EW-1 cells induced to differentiate, which corresponds to ZNF43, a multi-zinc finger protein containing the Krüppel-associated box (KRAB) transcriptional repression domain. Treatment of EW-1 cells with antisense oligonucleotides complementary to ZNF43 mRNA induces morphological differentiation and growth arrest. These findings suggest a role for ZNF43 in the maintenance of ES cells in an undifferentiated state, and that ZNF43 could be a primary target for differentiation stimuli in Ewing cells.

AbstractFatty acid status in humans is usually related to plasma or red blood cell fatty acid profiles. The aim of the study was to explore whether a maternal deficiency in dietary essential fatty acids would differentially affect lipid fractions in several tissues of the offspring, including brain. Female Wistar rats were fed an essential fatty acid-deficient diet during 3 months before mating. The fatty acid composition of different lipid fractions was examined in maternal milk, and in plasma, red blood cells, liver, adipose tissue, cerebral cortex and hippocampus of the offspring using thin layer and capillary column gas chromatography. Lipid fractions from most tissues of deprived offspring showed a common fatty acid profile characterized by elevated 20:3 ω9/20:4 ω6 ratio, and decreased docosahexaenoic acid and arachidonic acid. However, arachidonic acid was not affected in brain, even though 22:5 ω6 was increased in phospholipids of cerebral cortex and hippocampus. The present results demonstrate different degrees of resistance to essential fatty acid deficiency in lipid fractions and tissues. This suggests a priority distribution of arachidonic acid to preferential areas and shows that blood phospholipid fatty acids do not exactly reflect brain phospholipid status.

Hyperlipidemia and insulin resistance frequently develop after renal transplantation, contributing to cardiovascular disease. Individual differences in response based upon genetic variations in proteins regulating lipidic and glucose tolerance metabolism could be expected. In the general population, the S2 allelic variant of the apoprotein (apo) C‐III gene has been associated with hypertriglyceridemia and an insulin resistant state, whereas the E4 allele of the apo E has been associated with hypercholesterolemia and atherosclerosis. Its influence in renal transplant patients remains to be seen. In order to assess the impact of apo E and C‐III major polymorphisms on atherosclerotic vascular disease, lipid profile and impaired glucose tolerance in renal transplant patients, we studied 110 consecutively examined patients undergoing kidney transplantation (age range 24–73 years). Atherosclerotic complications were detected in 25% of patients, with age, male sex and hypercholesterolemia being significant atherosclerotic risk factors. Among the male patients with E4 allele, the odds ratio for coronary disease and global atherosclerosis were 10.2 (95% CI) and 6.4 (95% CI), respectively. There were no significant differences in the frequency of any of the polymorphisms among patients with dyslipidemia and impaired glucose tolerance. As the number of patients in our sample was small, larger studies are needed to verify these issues. While in the studied population C‐III polymorphism appears to have little association with the prevalence of atherosclerotic complications, E4 allele should be considered as a genetic marker of coronary artery disease and global atherosclerosis in renal transplant patients.

En las últimas décadas se han identificado diferentesfactores relacionados con la estenosis coronaria,cuya manifestación clínica, la cardiopatía isquémica,es la primera causa de muerte en lospaíses desarrollados. Distintos modelos experimentaleshan contribuido a definir alguno de estos factores,y a comprender la fisiopatología de los sucesosque tienen lugar en la pared arterial durante laformación de la lesión aterosclerótica. Actualmentese están tratando de establecer las bases genéticasrelacionadas con este fenómeno, que condicionanlas diferentes respuestas individuales ante unamisma situación. Dado el papel fundamental de losmecanismos de reparación endotelial en el desarrollode estas lesiones, los pacientes que sufren unproceso de reestenosis tras ser sometidos a intervencionesde revascularización, son un modelo útilpara el estudio de posibles condicionantes genéticosen el desarrollo de la lesión aterosclerótica.Recogemos, de los diferentes trabajos de la bibliografía,aquellos factores genéticos relacionadoscon los procesos de la formación del coágulo quepueden estar implicados en los fenómenos de reestenosistras una angioplastia coronaria transluminalpercutánea (ACTP), cuya caracterización podríaayudar a definir la terapéutica más adecuadapara cada individuo. Nos referimos a la reciente caracterizaciónde los genes que codifican los receptoresde membrana plaquetaria y su relación con elfibrinógeno, a la implicación del factor de la coagulaciónXa y del péptido inhibidor del activador delplasminógeno, así como al papel que puede desempeñarla apolipoproteína (a) en los fenómenos decoagulación.

Cases of hypomagnesaemia of hereditary renal origin represent at least three different congenital disorders of tubular reabsorption of magnesium (Mg).Isolated familial hypomagnesaemia has been reported in a heterogeneous group of patients and an autosomal dominant pattern of inheritance has often been found to be present.Familial hypokalaemia-hypomagnesaemia, inherited as an autosomal recessive trait, has been reported in 17 patients and we now describe 3 additional cases. Hypomagnesaemia is accompanied by hypokalaemia, metabolic alkalosis, hypocalciuria and moderate sodium chloride wasting. Titration of renal Mg reabsorption indicates the presence of a low threshold but a normal Tm. The inherited defect is probably situated at the level of the distal convoluted tubule and mimics the therapeutic effect of thiazides. This condition is frequently confused with Bartter's syndrome.Familial hypomagnesaemia-hypercalciuria, also inherited as an autosomal resessive trait, has been reported in at least 15 patients and we now add 3 new cases. Hypomagnesaemia is always accompanied by hypercalciuria and nephrocalcinosis. Ocular abnormalities such as myopia and horizontal nystagmus are often present. Hypermagnesiuria is of a greater degree than that observed in the previous entity and reflects a low Tm of Mg reabsorption. The defect must be situated at the level of the ascending limb of the loop of Henle and affects the transport of both calcium and Mg but not of sodium and chloride. This condition has not been clearly separated from hereditary distal renal tubular acidosis in the literature.