Jesús Gámiz Jiménez

Goat milk is less immunogenic than cow milk in a murine model of atopy.

Objectives: Cow milk protein allergy occurs in 2% to 6% of infants population. Goat milk has been used as an alternative to cow milk, but there is probably some cross-reactivity between the milks. Little is known about the allergenicity of goat milk per se. The aim of this study is to compare cow and goat milk allergenicity in a mouse atopy model. Methods: Balb/C mice were intragastrically sensitized to cow or goat milk by five doses administrated weekly. Six weeks after the first dose mice were killed, sera were collected and spleens removed for analysis. Results: The number of mice with diarrhea was significantly higher in the cow milk-sensitized group than in the goat milk-sensitized group. Serum cow milk-specific immunoglobulin G1 and histamine levels were also significantly higher in cow milk-sensitized mice. Cytokine production by spleen derived T cells showed a Th2 response with high levels of interleukin-4 production and low levels of interferon-γ in cow milk-sensitized mice. In addition, goat milk induced a lower lymphocyte sensitization as a result of a significant decrease in the specific proliferation ratio of these cells. Conclusion: Goat milk, when used as the first source of protein after a breast-feeding period, is less allergenic than cow milk in mice. Further studies are needed to clarify if goat milk is suitable as an alternative to cow milk in milk based formulas for infant nutrition.

Changes in fatty acid profiles of red blood cell membranes mediated by dietary nucleotides in weanling rats

Dietary nucleotides have been described to play multiple physiological roles. We examined the effect of feeding, for 4 weeks, nucleotide-supplemented diets (N-50 and N-250) on red blood cell (RBC) membrane fatty acid composition in weanling rats. Long-chain polyunsaturated fatty acids (LC-PUFA) of the n-6 series, especially arachidonic acid, increased in total RBC phospholipids in N-50 and N-250 groups. Concentrations of LC-PUFA of the n-3 series were preserved or slightly decreased. Saturates and monoenates also decreased. Phosphatidylethanolamine and sphingomyelin followed the variations observed for total phospholipids. Phosphatidylcholine showed a different response; saturated fatty acids increased while n-6 LC-PUFA decreased. Dietary nucleotides seem to affect the conversion of essential fatty acids to their long-chain derivatives in weanling rats in a similar way to that occurring in newborn infants during early life. These results show that the rat may be a valid model with which to study the biochemical mechanisms by which dietary nucleotides affect fatty acid desaturation.

Influences of Postnatal Age and Dietary Nucleotides on Plasma Fatty Acids in the Weanling Rat

Dietary nucleotides seem to play a number of physiologic roles during early life. They are improved in the maintenance of the immune system, intestinal maturation, and lipid metabolism. Nucleotides affect the conversion of essential fatty acids into their long-chain polyunsaturated (PUFA) derivatives in both preterm and at-term newborn infants. This work examines the effect of postnatal age and dietary nucleotides on the fatty acid composition of total plasma lipids and lipid fractions in the rat. Weanling rats (21 days old) were divided into three groups. The first group was killed, and the other two groups were fed a standard semipurified diet, and the same diet supplemented with 250 mg each of CMP, UMP, AMP, GMP, and IMP per 100 g of diet for 4 weeks. Advancing postnatal age led to an increase of total plasma fatty acids, especially saturated, and PUFA of the n-6 series, whereas PUFA of the n-3 series decreased. The fatty acid profile of plasma phospholipids (PL) exhibited minor changes, although there was a tendency to show lower levels of saturates and PUFA of the n-3 series and increased levels of PUFA of the n-6 series. Cholesteryl esters showed a response similar to that of PL, although the increase in arachidonic acid (20:4n-6) was significant. For triglycerides, linoleic acid (18:2n-6) and monounsaturates increased their levels, whereas saturates decreased. Dietary nucleotides mediated a significant increase in total plasma fatty acids, namely monounsaturated fatty acids and PUFA of both n-6 and n-3 series as compared with the control group. The relative fatty acid composition of PL and cholesteryl esters was mostly unaffected.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of a formula supplemented with n-3 and n-6 long-chain polyunsaturated fatty acids on plasma phospholipid, liver microsomal, retinal, and brain fatty acid composition in neonatal piglets

Abstract We explore in this study the influence of dietary (n-6) and (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) on tissues fatty acid composition in early life. Eight newborn piglets were fed sow milk for 20 days (group SM, n = 8); another sixteen newborn piglets were initially fed an adapted pig milk formula for 3 days and then assigned to receive for 17 days either the same adapted formula (group F, n = 8), or a formula supplemented with a phospholipid source of (n-6) and (n-3) LC-PUFA (group P, n = 8). Plasma phospholipid and liver microsomes 16:1(n-7) and 18:1(n-7) were increased in animals fed maternal milk compared with those fed formulas. Feeding the LC-PUFA formula produced significantly high plasma phospholipid and liver microsomal 22:6(n-3) than feeding the control formula. Similar plasma phospholipid and liver microsomal (n-6) and (n-3) LC-PUFA were found in animals fed SM and in those fed the control formula. The supplementation of LC-PUFA did not lead to any change in brain and retinal 20:4(n-6) and 22:6(n-3). No differences were found in brain and retinal 22:6(n-3) between animals fed the formula devoid of LC-PUFA and those fed sow milk. Retinal 22:4(n-6), 22:5(n-6) and 22:5(n-3) contents were significantly higher in maternal milk fed animals as compared with control formula fed animals. In brain, animals fed sow milk had higher (n-6) LC-PUFA than animals fed the supplemented formula. The results obtained in this study indicate that the supplementation of a phospholipid source of LC-PUFA influences plasma and liver microsomes 22:6(n-3). Under these experimental conditions, brain and retinal 22:6(n-3) were insensitive to the dietary supplementation.

EFFECT OF DIETARY NUCLEOTIDES AND OROTATE ON THE BLOOD LEVELS OF PROSTACYCLIN (PGI2) AND THROMBOXANE (TXA2) IN THE WEANLING RAT

Dietary nucleotides affect the maintenance of immune responses, tissue repair and polyunsaturated fatty acid metabolism. Orotate, a pyrimidine nucleotide precursor, induces fatty livers by impairing VLDL hepatic secretion. The aim of this study was to evaluate the changes in the blood levels of fatty acids and prostacyclin (PGI2) and thromboxane (TXA2) in the weanling rat caused by the dietary intake of nucleotides and orotate. Three groups of rats at weaning were fed a control diet, an orotate supplemented diet (O-50) and a nucleotide supplemented diet (N-50) during 4 weeks, respectively. Absolute values of plasma polyunsaturated fatty acids greater than 18 carbon atoms of the n-6 and n-3 series were increased in the N-50 group and decreased in O-50 with regard to the control. However, the relative fatty acid composition of plasma lipid fractions was mostly unaffected. Plasma 6-keto-PGF1 alpha showed a trend to be increased in N-50 and serum TXB2 was significantly increased in that group. Both eicosanoids were unchanged by dietary orotate intake. These results may be explained because of the increased plasma 20:4n-6 found in rats fed a supplemented nucleotide diet. Thus, nucleotides present in foods appear to modulate PUFA conversion and eicosanoids synthesis in early life.

¿Fíbulas peninsulares de codo «sículas» o de tipo «Monachil»? Novedades y revisión

We study a wide range of elbow fibulae, traditionally referred to as «siculas» in our Monachil nomenclature. This study will fulfill our knowledge of these problematic and paradigmatic devices in the Late Bronze in the Iberian Peninsula. The different typologies and chronologies are deeply analyzed, as well as their regional distribution, focusing on their native or foreign origin. Our aim is to build a chrono-cultural framework incorporating these fibulae. With the current information available, we cannot conclude that these Iberian fibulae have a Sicilian origin.

Changes in liver microscope lipids and plasma fatty acids induced by dietary orotate in the weanling rat

1. Dietary orotate produced a decrease in total plasma fatty acids which was reflected in low values of saturated, monounsaturated and polyunsaturated fatty acids longer than 18 carbon atoms of the n-6 series. The relative content of saturated fatty acids in microsomes of animals fed orotate was also decreased. 2. Rat liver delta-9 desaturase activity was lower in the group fed orotate. However, delta-6 desaturase activity did not show significant differences between the groups. 3. Microsomal cholesterol content was lower in rats fed orotate than in controls but phospholipid phosphorus contents were similar. These results suggest a direct effect of dietary orotate on the key enzymes which regulates cholesterol liver metabolism.