Maamar Souidi

Lipid atherogenic risk markers can be more favourably influenced by the cis-9,trans-11-octadecadienoate isomer than a conjugated linoleic acid mixture or fish oil in hamsters.

The aim of our present study was to compare the efficiency of conjugated linoleic acids (CLA) and fish oil in modulating atherogenic risk markers. Adult male hamsters were given a cholesterol-rich diet (0.6 g/kg) for 8 weeks; the diet was supplemented with 5 g cis-9,trans-11-CLA isomer/kg, 12 g CLA mixture (CLA-mix)/kg, 12 g fish oil/kg or 12 g fish oil+12 g CLA-mix/kg. The plasma cholesterol status was improved only with the cis-9,trans-11-CLA (HDL-cholesterol and HDL-cholesterol:LDL-cholesterol ratio, P<0.05), but was of borderline significance for CLA-mix (HDL-cholesterol:LDL-cholesterol ratio, P=0.06), with an increase (33-40 %) in the liver lipoprotein receptors (scavenger receptor-type I and LDL ApoB/E receptor) and HDL-binding protein 2 (P<0.05). A 100 % pigment gallstones incidence and a slight insulin resistance (homeostatic model assessment index) were observed in the CLA-mix-fed hamsters (P=-0.031). In comparison, fish-oil feeding alone improved merely the scavenger receptor-type I and HDL-binding protein 2 liver status and faeces sterol output. For most of our present observations, the concomitant intake of fish oil and CLA-mix gave dominant effects that were exclusive and specific to one or the other oil. In conclusion, part of the beneficial effects of CLA in the present study can be ascribed to the cis-9,trans-11-isomer, and these did not generally overlap with those of fish oil. In addition, the CLA-mix effects are clearly affected by the marine (n-3) fatty acids.

Concerted Uranium Research in Europe (CURE): toward a collaborative project integrating dosimetry, epidemiology and radiobiology to study the effects of occupational uranium exposure.

The potential health impacts of chronic exposures to uranium, as they occur in occupational settings, are not well characterized. Most epidemiological studies have been limited by small sample sizes, and a lack of harmonization of methods used to quantify radiation doses resulting from uranium exposure. Experimental studies have shown that uranium has biological effects, but their implications for human health are not clear. New studies that would combine the strengths of large, well-designed epidemiological datasets with those of state-of-the-art biological methods would help improve the characterization of the biological and health effects of occupational uranium exposure. The aim of the European Commission concerted action CURE (Concerted Uranium Research in Europe) was to develop protocols for such a future collaborative research project, in which dosimetry, epidemiology and biology would be integrated to better characterize the effects of occupational uranium exposure. These protocols were developed from existing European cohorts of workers exposed to uranium together with expertise in epidemiology, biology and dosimetry of CURE partner institutions. The preparatory work of CURE should allow a large scale collaborative project to be launched, in order to better characterize the effects of uranium exposure and more generally of alpha particles and low doses of ionizing radiation.