Brigitte Périquet

Micronutrient levels in HIV-1-infected children.

DesignProspective study. SettingThe study was performed on HIV-1-infected children at the Paediatric Haematology, and Oncology Unit of Toulouse Hospital, France. PatientsTwenty-one children, suffering from HIV-1 infection, and 21 control subjects of similar age (2–9 years) were included in the study. In the HIV-1-infected children, two subgroups were considered according to stage (non-AIDS or AIDS), based on the Centers for Disease Control, and Prevention 1987 criteria. ResultsThe first statistically significant deficiencies occurred at non-AIDS stage, and were confirmed at AIDS stage: P<0.05 for lycopene, retinol, tocopherol, and P< 0.001 for transthyretin, and serum albumin. Levels of copper (40%), and long-chain polyunsaturated fatty acids (21%) were higher in the non-AIDS group than the controls. ConclusionBiological impairing of the micronutrient levels was observed in the non-AIDS stage without clinical sign. This information is useful in delineating eventual, and well considered nutritional intervention strategies that may improve the clinical status of HIV-1-infected children, and perhaps alter the course of their disease.

Adipose Tissue Proadipogenic Redox Changes in Obesity

The role of inflammation and oxidative stress in the development of obesity and associated metabolic disorders is under debate. We investigated the redox metabolism in a non-diabetic obesity model, i.e. 11-week-old obese Zucker rats. Antioxidant enzyme activities, lipophilic antioxidant (α-tocopherol, coenzymes Q) and hydrophilic antioxidant (glutathione, vitamin C) contents and their redox state (% oxidized form), were studied in inguinal white fat and compared with blood and liver. The adipose tissues of obese animals showed a specific higher content of hydrophilic molecules in a lower redox state than those of lean animals, which were associated with lower lipophilic molecule content and lipid peroxidation. Conversely and as expected, glutathione content decreased and its redox state increased in adipose tissues of rats subjected to lipopolysaccharide-induced systemic oxidative stress. In these in vivo models, oxidative stress and obesity thus had opposite effects on adipose tissue redox state. Moreover, the increase in glutathione content and the decrease of its redox state by antioxidant treatment promoted in vitro the accumulation of triglycerides in preadipocytes. Taken together and contrary to the emergent view, our results suggest that obesity is associated with an intracellular reduced redox state that promotes on its own the development of a deleterious proadipogenic process.

Biological validation of coenzyme Q redox state by HPLC‐EC measurement: relationship between coenzyme Q redox state and coenzyme Q content in rat tissues

The properties of coenzymes Q (CoQ9 and CoQ10) are closely linked to their redox state (CoQox/total CoQ) × 100. In this work, CoQ redox state was biologically validated by high performance liquid chromatography‐electrochemical measurement after modulation of mitochondrial electron flow of cultured cells by molecules increasing (rotenone, carbonyl cyanide chlorophenylhydrazone) or decreasing (antimycin) CoQ oxidation. The tissue specificity of CoQ redox state and content were investigated in control and hypoxic rats. In control rats, there was a strong negative linear regression between tissular CoQ redox state and CoQ content. Hypoxia increased CoQ9 redox state and decreased CoQ9 content in a negative linear relationship in the different tissues, except the heart and lung. This result demonstrates that, under conditions of mitochondrial impairment, CoQ redox control is tissue‐specific.

Site specific changes of redox metabolism in adipose tissue of obese Zucker rats

Adipose tissues are differently involved in lipid metabolism and obesity according to their type and location. Increasing reports stress on the impact of redox metabolism on obesity and metabolic syndrome. The aim of this work is to investigate the site‐specific redox metabolism in three different adipose tissues and its changes occurring in obesity. We analysed enzymatic and non‐enzymatic parameters, and focused on the reduced/oxidized glutathione and coenzyme Q couples. In lean compared with obese non‐diabetic Zucker rats, interscapular brown fat seems well protected against oxidative stress and epididymal adipose tissue shows a more reduced glutathione redox state, associated with a higher susceptibility to lipophilic oxidative stress than inguinal adipose tissue. Epididymal adipose tissue redox metabolism significantly differs from inguinal one by its limited redox metabolism adaptation. Our results demonstrate site‐specific managements of reactive oxygen species metabolism in obese Zucker rats. These results are not consistent with the classic deciphering of inflammatory situation and produce a new conception of the redox parameters implication in the development of the metabolic syndrome.

Positive impact of long-term lifestyle change on erythrocyte fatty acid profile after acute coronary syndromes.

BACKGROUND The outcome of coronary diseases is influenced by lifestyle and diet. Among dietary factors, n-3 polyunsaturated fatty acids reduce mortality from cardiovascular diseases. AIMS To evaluate the impact of dietary and lifestyle advice by calculation of scores and analysis of plasmatic lipids and the fatty acid composition of erythrocyte membrane phospholipids after 1 year of patient education in 66 patients with acute coronary syndromes. METHODS The answers given by patients during questioning were transformed into scores (atherosclerosis risk, dietary habits and global scores) at inclusion and after 1 year of follow-up. Classical metabolic risk factors and fatty acid composition of erythrocyte phospholipids were determined at the same time. RESULTS After 1 year of education, patients improved their different scores, particularly by changing dietary habits. The positive impact was seen in the blood lipid and erythrocyte fatty acid levels: plasma low-density lipoprotein cholesterol and triglyceride concentrations were lowered and n-3 polyunsaturated fatty acid percentages were improved in phospholipids. CONCLUSION Global score, lipid variables and the nature of the polyunsaturated fatty acids in erythrocyte phospholipids help us to evaluate patients with high coronary artery disease risk and the benefits of long-term dietary and lifestyle advice.

Total parenteral nutrition decreases liver oxidative metabolism and antioxidant defenses in healthy rats: comparative effect of dietary olive and soybean oil.

BACKGROUND Total parenteral nutrition (TPN) is used for critically ill patients undergoing surgery, after trauma, or during disease conditions that favor oxidative stress. We studied the effect of TPN on liver oxidative metabolism and antioxidant defenses in rats, and we compared the effect of soybean oil- and olive oil-based diets. METHODS Seven-week-old rats (n = 28) were divided into four groups. Two experimental groups received a TPN solution containing soybean oil (TPN-S) or a mixture of olive/soybean oil, 80/20 (TPN-O), IV for 6 days. Orally fed animals received a solid diet including soybean oil (Oral-S) or olive/soybean oil, 80/20 (Oral-O). The following parameters were measured: DL-alpha-tocopherol, vitamin A, malondialdehyde and thiobarbituric acid reactive substances (MDA-TBARS), and total radical-trapping antioxidant parameter (TRAP) in serum; DL-alpha-tocopherol, vitamin A, glutathione (GSH), and catalase (Cat) activity in liver homogenate; fatty acids from phospholipid, cytochrome P-450 content, NADPH-cytochrome c2 reductase activity in liver microsomes; superoxide dismutase (SOD), glutathione peroxidase (Gpx), glutathione reductase (GR), glutathione transferase (GST), and glucose-6-phosphate dehydrogenase (G6PD) in liver cytosol. RESULTS The soybean or olive oil diets modified the liver microsomal fatty acid phospholipid composition, but the unsaturation index remained unchanged. TPN specifically increased the saturation of the membrane. The cytochrome P-450 level and the NADPH-cytochrome c2 reductase, SOD, Gpx, Cat, and GST activities were unchanged by soybean oil or olive oil diet but decreased receiving TPN. CONCLUSIONS In rats, TPN decreased the liver oxidative metabolism and enzymatic antioxidant defenses. This may be related to saturation of the liver microsomal fatty acids.

Retinol and retinyl ester concentrations in rat tissues during total parenteral nutrition

Abstract We have previously observed that continuous total parenteral nutrition (TPN) that supplies retinyl palmitate induces a strong decrease of the circulating retinol, which is associated with an impaired hepatic production of retinol-binding protein. We have investigated the effect of 7 days of TPN on the retinol and retinyl ester concentrations in rat tissues, relative to the vitamin A status [n = 30 for vitamin A-sufficient (A+) and n = 30 for deficient (A−)]. Rats were cannulated for intravenous feeding (n = 12 for TPN-A+, n = 12 for TPN-A−) and were compared with their per os pair-fed counterparts (n = 12 for O-A+ and n = 12 for O-A−). Retinol and retinoic acid in serum and retinol and retinyl ester concentrations in liver, kidney, lung, heart, and testis were measured by high performance liquid chromatography. TPN induced a dramatic decrease in circulating retinol of A+ rats, whereas retinoic acid concentration in serum was unchanged. When TPN was given to A− rats, retinol concentration in serum remained low. Lower retinol and retinyl ester concentrations were measured in the livers of TPN rats compared with orally pair-fed rats, no matter the initial vitamin A status (P

Retinol storage in the rat liver after daily intramuscular administration of physiological doses of a vitamin A oil emulsion.

We have recently shown the kinetic behavior of liver retinyl esters in rats with adequate vitamin A levels receiving oral vitamin supplementation. In the present work we have studied the effects of intramuscular administration of a vitamin A preparation on the metabolism of vitamin A in the rat. Retinol administered intramuscularly to rats in the form of an emulsion brought about a significant increase in the serum and liver concentration of vitamin A; this increase was slightly less than in orally treated rats. In each group, retinyl palmitate constituted 80-85% of the total retinyl esters, followed by stearate (9-13%), laurate, palmitoleate, myristate, linoleate and pentadecanoate making up 3-10%. The subcellular localization of all retinyl esters is similar and dependent on age but not on the route of administration. These results indicate that although the best hepatic storage is achieved with an orally administered vitamin A emulsion, the intramuscular administration of a physiological dose might provide an effective supplementation method if oral vitamin A is contraindicated.