Effects of fish oil on the neuro-endocrine responses to an endotoxin challenge in healthy volunteers

Résumé Introduction et hypothèse : Certains acides gras polyinsaturés de type n-3 PUFA, qui sont contenus dans l'huile de poisson, exercent des effets non-énergétiques (fluidité des membranes cellulaires, métabolisme énergétique et prostanoïdes, régulation génique de la réponse inflammatoire). Les mécanismes de la modulation de cette dernière sont encore mal connus. L'administration d'endotoxine (LPS) induit chez les volontaires sains une affection inflammatoire aiguë, comparable à un état grippal, associé à des modifications métaboliques et inflammatoires transitoires, similaires au sepsis. Ce modèle est utilisé de longue date pour l'investigation clinique expérimentale. Cette étude examine les effets d'une supplémentation orale d'huile de poisson sur la réponse inflammatoire (systémique et endocrinienne) de sujets sains soumis à une injection d'endotoxine. L'hypothèse était que la supplémentation d'huile de poisson réduirait les réponses physiologiques à l'endotoxine. Méthodes : Quinze volontaires masculins (âge 26.0±3.1 ans) ont participé à une étude randomisée, contrôlée. Les sujets sont désignés au hasard à recevoir ou non une supplémentation orale : 7.2 g d'huile de poisson par jour correspondant à un apport de 1.1 g/jour d'acides gras 20:5 (n-3, acide écosapentaénoïque) et 0.7 g/jour de 22:6 (n-3, acide docosahexaénoïque). Chaque sujet est investigué deux fois dans des conditions identiques : une fois il reçoit une injection de 2 ng par kg poids corporel de LPS intraveineuse, l'autre fois une injection de placebo. Les variables suivantes sont relevées avant l'intervention et durant les 360 min qui suivent l'injection :signes vitaux, dépense énergétique (EE) et utilisation nette des substrats (calorimétrie indirecte, cinétique du glucose (isotopes stables), taux plasmatique des triglycérides et FFA, du glucose, ainsi que des cytokines et hormones de stress (ACTH, cortisol, Adré, Nor-Adré). Analyses et statistiques :moyennes, déviations standards, analyse de variance (one way, test de Scheffé), différences significatives entre les groupes pour une valeur de p < 0.05. Résultats :L'injection de LPS provoque une augmentation de la température, de la fréquence cardiaque, de la dépense d'énergie et de l'oxydation nette des lipides. On observe une élévation des taux plasmatiques de TNF-a et IL-6, de la glycémie, ainsi qu'une élévation transitoire des concentrations plasmatiques des hormones de stress ACTH, cortisol, adrénaline et noradrénaline. L'huile de poisson atténue significativement la fièvre, la réponse neuro-endocrinienne (ACTH et cortisol) et sympathique (baisse de la noradrénaline plasmatique). Par contre, les taux des cytokines ne sont pas influencés par la supplémentation d'huile de poisson. Conclusion : La supplémentation d'huile de poisson atténue la réponse physiologique à l'endotoxine chez le sujet sain, en particulier la fièvre et la réponse endocrinienne, sans influencer la production des cytokines. Ces résultats soutiennent l'hypothèse que les effets bénéfiques de l'huile de poisson sont principalement caractérisés au niveau du système nerveux central, par des mécanismes non-inflammatoires qui restent encore à élucider.

Short-term and sustained renal effects of angiotensin II receptor blockade in healthy subjects.

We investigated the short-term and sustained hormonal and renal effects of angiotensin II (Ang II) receptor blockade in normotensive healthy volunteers. Twenty-four subjects maintained on a fixed sodium diet were randomized to receive for 8 days a placebo or 10 or 50 mg doses of the Ang II antagonist irbesartan (SR 47436, BMS 186295) according to a double-blind, parallel group design. Plasma renin activity, plasma immunoreactive Ang II and aldosterone levels, blood pressure, renal hemodynamics, and urinary electrolyte excretion were measured for 8 hours after the first and eighth administration of each dose of irbesartan or placebo. Ang II receptor blockade with irbesartan induced a dose-dependent compensatory increase in plasma renin activity and plasma angiotensin levels and a significant decrease in plasma aldosterone levels. The compensatory rise in plasma renin activity and Ang II levels was more pronounced on day 8, reflecting a long duration of the blocking effect of irbesartan. Irbesartan induced small changes in blood pressure and did not significantly modify renal blood flow and glomerular filtration rate. However, a significant decrease in filtration fraction was observed during receptor blockade on days 1 and 8. The tubular effects of irbesartan were characterized by a dose-dependent increase in sodium and chloride excretions. Interestingly, the cumulative natriuretic response to Ang II receptor blockade was similar on days 1 and 8, suggesting that in these subjects, renal Ang II receptors are not blocked over 24 hours during repeated administration even though this antagonist has a long duration of action (t1/2 of 15 to 17 hours).(ABSTRACT TRUNCATED AT 250 WORDS)

Healthy, educated and wealthy : Is the welfare state really harmful for growth?

In this paper, we study how public and private expenditures in health and education affect economic growth by their influence on people's health, abilities, skills and knowledge. We consider a growth accounting framework in order to test whether welfare expenditures more than offset the efficiency losses caused by distortionary taxation, and whether the effects of public expenditure on economic growth differ from those of private expenditure. Our empirical analysis is based on a panel of 19 OECD countries observed between 1971 and 1998. The results are consistent with the hypothesis that the contribution of welfare expenditures more than compensates for the distortions caused by the tax system; and the estimated positive impact is stronger for health than for education. We also find some evidence that public expenditure influences GDP growth more than private expenditure.

Healthy Family Newsletter, January 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, February2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, March 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, April 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, May 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, August 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, September 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, October 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, November 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, December 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, December 2010

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.

Healthy Family Newsletter, January 2011

The Iowa Dept. of Public Health, Iowa's Food Assistance Program provides nutrition assistance to people with low income. It can help you buy nutritious foods for a better diet, this newsletter is provided to help instruct people about healthy food choices.