Face aux besoins et à la réalité des consommations, quelles sont les spécificités des différentes sources d’acides gras oméga 3 disponibles ?

Les données de consommation en acides gras oméga 3 de la population française montrent les déficits d’apports, en particulier en acide alpha-linolénique (ALA), compte tenu des ANC (apports nutritionnels conseillés). En regard de ces données et des sources actuellement utilisées, les spécificités des différents vecteurs alimentaires des oméga 3 sont décrites. L’étude Aquitaine a montré que les lipides d’origine animale contribuaient à 73 % de l’apport alimentaire en ALA. Augmenter le contenu de celui-ci dans les produits d’animaux d’élevage via leur alimentation dans laquelle on introduit des sources d’ALA (colza, lin) ou de DHA (huiles de poissons) représente une stratégie d’optimisation. À cet égard, les résultats sont plus intéressants avec les monogastriques comparés aux polygastriques. En dépit de son potentiel, le vecteur des huiles végétales est trop peu exploité, il n’apporte actuellement que 9 % de l’apport global d’ALA. Pour couvrir les besoins en ALA, sans modification des autres habitudes alimentaires, il faudrait que l’ALA représente 8 % des acides gras totaux consommés sous forme d’huile, contre 0,5-0,6 % actuellement. Les spécificités de trois huiles linoléniques sont comparées. Par rapport aux objectifs, l’huile de colza présente les caractéristiques les plus intéressantes

The activation of neuronal NO synthase is mediated by Gâ protein βγ subunit and the tyrosine phosphatase SHPâ 2

In CHO cells we had found that CCK positively regulated cell proliferation via the activation of a soluble guanylate cyclase. Here we demonstrate that CCK stimulated a nitric oxide synthase (NOS) activity. The production of NO was involved in the proliferative response elicited by CCK regarding the inhibitory effect of NOS inhibitors Lâ NAME and αâ guanidinoglutaric acid. We identified the NOS activated by the peptide as the neuronal isoform: the expression of the C415A neuronal NOS mutant inhibited both CCKâ induced stimulation of NOS activity and cell proliferation. These two effects were also inhibited after expression of the C459S tyrosine phosphatase SHPâ 2 mutant and the βARKl (495â 689) sequestrant peptide, indicating the requirement of activated SHPâ 2 and Gâ βγ subunit. Kinetic analysis (Western blot after coimmunoprecipitation and specific SHPâ 2 activity) revealed that in response to CCKâ treatment, SHPâ 2 associated to Gâ β1 subunit, became activated, and then dephosphorylated the neuronal NOS through a direct association. These data demonstrate that the neuronal NOS is implicated in proliferative effect evoked by CCK. A novel growth signaling pathway is described, involving the activation of neuronal NOS by dephosphorylation of tyrosyl residues.â Cordelier, P., Estève, J.â P., Rivard, N., Marletta, M., Vaysse, N., Susini, C., Buscail, L. The activation of neuronal no synthase is mediated by Gâ protein βγ subunit and the tyrosine phosphatase SHPâ 2. FASEB J. 13, 2037â 2050 (1999)Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154447/1/fsb2fasebj13142037.pd

Differential impact of milk fatty acid profiles on cardiovascular risk biomarkers in healthy men and women

International audienceObjectives: to evaluate the impact of three specific ruminant (R) milk fats resulting from modification of the cow's diet on cardiovascular risk factors in healthy volunteers. R-milk fats were characterized by increased content in total trans fatty acids (R-TFA) and parallel decrease in saturated fatty acids (SFA). Methods: 111 healthy, normolipemic men and women have been recruited for a monocentric, randomised, double-blind, and parallel intervention, 4-week controlled study. Volunteers consumed 3 experimental products (butter, dessert cream and cookies) made with one of the 3 specific milk fats (55 g fat/day). During the first week (run-in period), the subjects consumed on a daily basis dairy products containing 72% SFA/2.85% R-TFA (called "L0"). For the next 3 weeks of the study (intervention period), the first group continued to consume L0 products. The second group received dairy products containing 63.3% SFA/4.06% R-TFA (called "L4"), and the third group received dairy products containing 56.6% SFA/12.16% R-TFA (called "L9"). Results: plasma concentrations of HDL-cholesterol was not significantly altered by either diet (p = 0.38). Compared to L0 diet, L4 diet contributed to reduce LDL-cholesterol (-0.140.38 mmol/L, p= 0.04), total cholesterol (-0.130.50 mmol/L, p = 0.04), LDL-cholesterol/HDL-cholesterol (-0.140.36, p = 0.03) and total cholesterol/HDL-cholesterol (-0.180.44, p = 0.02). Conclusion: different milk fat profiles can change cardiovascular plasma parameters in human healthy volunteers. A limited increase of the R-TFA/SFA ratio in dairy products is associated with an improvement in some cardiovascular risk factors. However, a further increase in R-TFA/SFA ratio has no additional benefit

Particulate matter exposure during pregnancy is associated with birth weight, but not gestational age, 1962-1992: a cohort study

<p>Abstract</p> <p>Background</p> <p>Exposure to air pollutants is suggested to adversely affect fetal growth, but the evidence remains inconsistent in relation to specific outcomes and exposure windows.</p> <p>Methods</p> <p>Using birth records from the two major maternity hospitals in Newcastle upon Tyne in northern England between 1961 and 1992, we constructed a database of all births to mothers resident within the city. Weekly black smoke exposure levels from routine data recorded at 20 air pollution monitoring stations were obtained and individual exposures were estimated via a two-stage modeling strategy, incorporating temporally and spatially varying covariates. Regression analyses, including 88,679 births, assessed potential associations between exposure to black smoke and birth weight, gestational age and birth weight standardized for gestational age and sex.</p> <p>Results</p> <p>Significant associations were seen between black smoke and both standardized and unstandardized birth weight, but not for gestational age when adjusted for potential confounders. Not all associations were linear. For an increase in whole pregnancy black smoke exposure, from the 1^st(7.4 μg/m³) to the 25^th(17.2 μg/m³), 50^th(33.8 μg/m³), 75^th(108.3 μg/m³), and 90^th(180.8 μg/m³) percentiles, the adjusted estimated decreases in birth weight were 33 g (SE 1.05), 62 g (1.63), 98 g (2.26) and 109 g (2.44) respectively. A significant interaction was observed between socio-economic deprivation and black smoke on both standardized and unstandardized birth weight with increasing effects of black smoke in reducing birth weight seen with increasing socio-economic disadvantage.</p> <p>Conclusions</p> <p>The findings of this study progress the hypothesis that the association between black smoke and birth weight may be mediated through intrauterine growth restriction. The associations between black smoke and birth weight were of the same order of magnitude as those reported for passive smoking. These findings add to the growing evidence of the harmful effects of air pollution on birth outcomes.</p

Face aux besoins et à la réalité des consommations, quelles sont les spécificités des différentes sources d’acides gras oméga 3 disponibles ?

Les données de consommation en acides gras oméga 3 de la population française montrent les déficits d’apports, en particulier en acide alpha-linolénique (ALA), compte tenu des ANC (apports nutritionnels conseillés). En regard de ces données et des sources actuellement utilisées, les spécificités des différents vecteurs alimentaires des oméga 3 sont décrites. L’étude Aquitaine a montré que les lipides d’origine animale contribuaient à 73 % de l’apport alimentaire en ALA. Augmenter le contenu de celui-ci dans les produits d’animaux d’élevage via leur alimentation dans laquelle on introduit des sources d’ALA (colza, lin) ou de DHA (huiles de poissons) représente une stratégie d’optimisation. À cet égard, les résultats sont plus intéressants avec les monogastriques comparés aux polygastriques. En dépit de son potentiel, le vecteur des huiles végétales est trop peu exploité, il n’apporte actuellement que 9 % de l’apport global d’ALA. Pour couvrir les besoins en ALA, sans modification des autres habitudes alimentaires, il faudrait que l’ALA représente 8 % des acides gras totaux consommés sous forme d’huile, contre 0,5-0,6 % actuellement. Les spécificités de trois huiles linoléniques sont comparées. Par rapport aux objectifs, l’huile de colza présente les caractéristiques les plus intéressantes

Effets du tétrapeptide CCK-4 sur la sécrétion pancréatique exocrine du rat in vitro et in vivo

International audienc