[Gallstone biochemical characteristics using Fourier transform infrared spectroscopy method]. / Caractéristiques biochimiques des lithiases vésiculaires par spectrométrie infrarouge à Abidjan.

This study reports biochemical composition and morphological aspect of gallstones as investigated by spectroscopy IR method. Participants were 24 patients composed of 12 males and 12 females who underwent cholecystectomy with age mean of 44.8 years. The gallstones were classified either as pigments stones (n = 12), cholesterol stones (n = 8) or as mixed stones (n = 4) according to analysis by Fourier transform infrared spectroscopy. The infrared spectroscopy quantification reported eight stones contained 100% of cholesterol, eight of 100% of calcium bilirubinate, four stones were composed of 65% calcium bilirubinate phosphate and 35% calcium carbonate, and four stones contained 65% cholesterol, 30% neutral calcium bilirubinate, 5% protein and traces of calcium bilirubinate acid. Our findings showed that most gallstones were composed of pigment stones with relative large proportion of cholesterol stones, whereas previous study in Caucasian reported predominance of cholesterol stones. These findings indicate the influence of diet and chronic haemolysis in the stones formation in regard to biochemical composition differences between those found in European area and our results. Therefore, Fourier transform infrared spectroscopy method allowed to determine quality and quantity of biochemical components of gallstones. Therefore, a careful survey must allow knowing the nutritional and environmental factors in the occurrence of gallstones to Côte d'Ivoire, in order to prevent this disease.

Lack of beta-catenin in early life induces abnormal glucose homeostasis in mice.

AIMS/HYPOTHESIS: Wingless and iNT-1 (WNT) pathway members are critical for pancreatic development and exocrine tissue formation. Recently, much attention has focused on delineating the roles of beta-catenin in pancreatic organogenesis. However, little is known about the involvement of beta-catenin in the endocrine or exocrine function of the mature pancreas. We report for the first time the impact of beta-catenin deletion in the pancreatic beta cells. METHODS: We targeted the deletion of the beta-catenin gene in pancreatic beta cells by crossing a floxed beta-catenin mouse strain with a RIP-Cre mouse strain. RESULTS: Surprisingly, the majority of the mutant mice died shortly after birth and had deregulated glucose and insulin levels. The newborn mutant pancreases demonstrated increased insulin content, reflecting a defect in insulin release confirmed in vitro. Moreover, there was a reduction in total endocrine tissue at birth, while cellularity in islets was greater, suggesting that lack of beta-catenin affects beta cell size. Some newborns survived beta-catenin deletion and showed a milder phenotype during adulthood. CONCLUSIONS/INTERPRETATION: The deletion of beta-catenin in the maturing beta cells negatively impacts on islet morphology and function. This work reveals that lack of beta-catenin in early life is related to severe deregulation of glucose homeostasis.

Characteristics of undiagnosed diabetes in community-dwelling French elderly: the 3C study.

We aimed to assess clinical and socio-demographic characteristics of undiagnosed diabetes, including glucose control, in French community-living elderly people. Diagnosed and undiagnosed diabetes, impaired fasting glucose (IFG) and characteristics of subjects were assessed by interview, clinical examination and fasting blood glucose measures at the baseline visit of the Three-City (3C) study including 9294 people over 65 in three urban areas in France. In the Bordeaux sample, HbA1c was measured in diabetic and IFG subjects and in a sub-sample of non-diabetic subjects. The proportion of diagnosed diabetes, undiagnosed diabetes and IFG was, respectively, 8.2%, 1.4% and 3.6%. Diabetic and IFG subjects were more likely to be men, to suffer from hypertension and to be overweight. They were less likely to have a high income and more likely to have a lower educational level. These factors were unrelated to knowledge of diabetic status. In the Bordeaux sub-sample, 19.6% of the diagnosed diabetic subjects and 16.1% of those undiagnosed had an HbA1c greater than 8%. Prevalence of ischemic heart disease was more common in diagnosed than in undiagnosed diabetic subjects (P=.021). A significant number of undiagnosed elderly had poor glucose control suggesting a potential benefit for diabetes screening in the elderly.

Short-term insulin therapy and normoglycemia. Effects on erythrocyte lipid peroxidation in NIDDM patients.

OBJECTIVE: To evaluate erythrocyte lipid peroxidation (LPO) before and after an adaptive short-term insulin therapy in NIDDM patients who were chronically hyperglycemic. RESEARCH DESIGN AND METHODS: Twenty-six patients with NIDDM (mean HbA1c, 11.28%) aged 53.04 +/- 2.03 years were submitted for 3 days to constant intravenous glucose and continuous insulin perfusion at an adaptable rate to maintain glycemia within the normal range. An evaluation of LPO at baseline and after euglycemic insulin therapy was determined by erythrocyte free and total malondialdehyde (MDA) levels, polyunsaturated fatty acid (PUFA) percentage, vitamin E and glutathione content, and the following antioxidant enzymatic activity determinations: glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT). Fasting serum glucose, HbA1c, triglycerides, cholesterol, and HDL cholesterol levels were also determined at these time points. RESULTS: At baseline, erythrocyte free and total MDA were significantly higher in NIDDM patients than in control subjects (11.14 +/- 0.80 vs. 1.74 +/- 0.11 nmol/g Hb [P < 0.0001] for free MDA; 18.04 +/- 1.79 vs. 7.85 +/- 0.55 nmol/g Hb [P < 0.0001] for total MDA). PUFAs, particularly C20:4 and C22:5, were increased (14.69 +/- 0.34 vs. 12.03 +/- 0.31 and 2.31 +/- 0.04 vs. 1.71 +/- 0.03% of total fatty acids, respectively). Vitamin E and glutathione were reduced significantly (6.16 +/- 0.61 vs. 14.84 +/- 0.64 nmol/g Hb and 0.42 +/- 0.04 vs. 0.97 +/- 0.06 mmol/l, respectively). No difference was observed for the enzymatic activities. After euglycemic insulin therapy, triglycerides significantly decreased compared with baseline concentrations (1.55 +/- 0.13 vs. 2.42 +/- 0.22 mmol/l; P < 0.001), whereas other lipidic parameters were unchanged. Free MDA significantly decreased (8.60 +/- 0.76 vs. 11.14 +/- 0.80 nmol/g Hb [P < 0.01]), while vitamin E increased (7.93 +/- 0.73 vs. 6.16 +/- 0.61 nmol/g Hb [P < 0.05]). No difference was observed for PUFAs, glutathione, or total MDA. CONCLUSIONS: The observed erythrocyte LPO in NIDDM decreased after a short-term adaptive insulin therapy. This decrease could be principally attributed to the normalized glycemia that reduces reactive oxygen species (ROS) production, which in turn may explain the increase in erythrocyte membrane vitamin E and the decrease in MDA. This study shows the value of a euglycemic environment in NIDDM to reduce LPO and, at long range, to minimize clinical diabetes complications.

Lipoperoxidation in plasma and red blood cells of patients undergoing haemodialysis: vitamins A, E, and iron status.

In 14 patients undergoing haemodialysis, lipoperoxidation (LPO) processes were determined in plasma and red blood cells (RBC) before and after a dialysis session by determining (a) the direct substrate, polyunsaturated fatty acids (PUFA); (b) the end product of LPO, malondialdehyde (MDA); and (c) the hydrophobic antioxidant systems, vitamins A and E. In plasma before dialysis, linoleic and arachidonic acid, and the antioxidant vitamin E, were significantly lowered as compared to the healthy controls (p < 0.05). On the contrary, the free MDA level was enhanced (p < 0.05). These results were emphasized by a dialysis session. In RBC of these patients, no difference in linoleic acid, free MDA, or vitamin E level were observed before or after dialysis when compared to controls. However, only vitamin A was significantly higher in haemodialysis patients (before and after dialysis) and in renal failure patients (p < 0.05) than in the healthy control group. The present results suggest that increased RBC vitamin A may offer some degree of protection against oxidative stress in erythrocytes, but not in plasma where LPO is demonstrated.

Antioxidant effects of a supplemented very low protein diet in chronic renal failure.

Increased peroxidation of lipids in red blood cells (RBC) in patients with advanced chronic renal failure (CRF) reflects increased generation of reactive oxygen species (ROS), which may contribute to the metabolic damage induced by CRF and to its progression. We have evaluated parameters indicative of lipoperoxidation (LPO) of RBC at baseline in patients with CRF compared to controls, and the effects of a very low protein diet supplemented with amino and keto acids and vitamins A, C, E (VLPD) over a 6-month period. The presence of peroxidation damage in CRF patients before the administration VLPD was demonstrated by elevated levels of free malondialdehyde (MDA) (p < .0003) and decreased levels of polyunsaturated fatty acids (PUFA), particularly C20:4 (p < .001), C22:4 (p < .0001) and C22:5 (p < .0001) when compared to controls. Similarly, RBC vitamin E content was significantly decreased (p < .0001) while enzymatic activities were unalterated. VLPD reduced erythrocyte LPO as suggested by (a) decreased levels of free and total RBC MDA (p < .003 and p < .03, respectively), (b) increased levels of PUFA, particularly C22:4 and C22:5 (p < .003 and p < .03, respectively), and (c) increased levels of vitamins A and E (p < .001 and p < .04, respectively) as compared to prediet results. Antioxidant enzyme activities were not modified. These results suggest that VLPD has a protective role against LPO of erythrocytes in patients with CRF.

The enzymatic antioxidant system in blood and glutathione status in human immunodeficiency virus (HIV)-infected patients: effects of supplementation with selenium or beta-carotene.

To investigate the effects of selenium or beta-carotene supplementation in human immunodeficiency virus (HIV)-infected patients, who are known to have deficiencies of selenium and vitamin A, we evaluated the blood enzymatic antioxidant system, including superoxide dismutase (SOD), selenodependent glutathione peroxidase (GPX), and catalase (Cat); glutathione (GSH) status; and plasma selenium concentration. The placebo group consisted of 18 HIV-infected patients with no supplementation, the selenium group was composed of 14 patients receiving oral selenium treatment, and the beta-carotene group comprised 13 patients receiving oral beta-carotene supplementation. All groups were studied for 1 y. At the beginning of the study, a significantly higher SOD activity (P < 0.001) was observed in all HIV-infected patients compared with uninfected control subjects, and GPX activity at baseline was higher in the placebo (P < 0.004) and selenium (P < 0.014) groups than in the control subjects. These higher enzyme activities could be related to an increased synthesis of these enzymes in erythrocyte precursors under oxidative stress. Moreover, we observed significantly lower GSH values in all HIV-infected patients than in control subjects at the beginning of the study (P < 0.001). After selenium or beta-carotene supplementation, no significant difference was observed for SOD activity compared with baseline. On the contrary, GPX activity increased significantly after selenium treatment (P < 0.04 between 3 and 6 mo), whereas a slight increase was found after beta-carotene treatment. Similarly, a significant increase in GSH values was observed at 12 mo compared with baseline both after selenium supplementation (P < 0.001) and beta-carotene supplementation (P < 0.01). Because GPX and GSH play an important role in the natural enzymatic defense system in detoxifying hydrogen peroxide in water, selenium supplementation could be of great interest in protecting cells against oxidative stress. The lower efficiency of beta-carotene could be attributed to the seriousness of the pathology at the time of recruitment into the beta-carotene group.

Absence of "A"-esterase activity in the serum of a patient with Tangier disease.

The levels of apolipoprotein A-I, A-II and B in subjects who are homozygous or heterozygous for Tangier disease are reported and compared with the amount of "A"-esterase in the serum. The "A"-esterases hydrolyse toxic organophosphate pesticides and are currently classified by the nomenclature committee of the International Union of Biochemistry as arylesterases (EC 3.1.1.2) although recent evidence has cast doubt on this classification. The apolipoprotein data are consistent with previous data reported for a number of Tangier patients. The homozygote has a marked reduction in apo A-I and A-II levels and a 30% reduction in apo B. The heterozygotes have about a 50% reduction of apo A-I, a slight reduction in apo A-II and no change in apo B. These apolipoprotein values correspond to a marked reduction in HDL cholesterol for the homozygote and substantial reductions in the heterozygotes. The "A"-esterase activity is zero in one homozygote while heterozygotes have about 5% of the levels in control subjects. Arylesterase activity appears to be essentially normal. The data thus support previous observations that the HDL "A"-esterase activity is greatly reduced in those conditions where HDL apo A-I is markedly reduced, e.g., in "Fish-eye" Disease.

Fatty acids and plasma antioxidants in HIV-positive patients: correlation with nutritional and immunological status.

OBJECTIVE: To investigate red blood cell (RBC) and plasma fatty acids (FA) in HIV-positive patients in relation to oxidative stress and nutritional or immunological status. DESIGN AND METHODS: FA, plasma selenium, vitamins A and E were measured in 95 patients divided into four groups according to CD4 cells. RESULTS: Poly- and di-unsaturated FA (PUFA, DUFA) decreased and saturated FA (SFA) increased in RBC in the patients below 400/mm3 and in plasma in the patients below 50/mm3. RBC SFA correlated to CD4 cells, PUFA to MDA. Unlike vitamin E, plasma vitamin A and selenium decreased in most groups. Plasma SFA and MUFA correlated negatively to selenium and PUFA and DUFA to vitamin E. No correlation was found between PUFA and nutritional markers. CONCLUSION: FA seem to be modified during HIV infection by oxidative stress and disease evolution, but not by denutrition.

Relationship between red blood cell antioxidant enzymatic system status and lipoperoxidation during the acute phase of malaria.

OBJECTIVE: To investigate the relationship between oxidative stress and aggrevation of the disease in patients with malaria. METHODS AND RESULTS: In the present study lipoperoxidation was demonstrated during the acute phase of malaria by a significant decrease in polyunsaturated fatty acids (PUFA). The lowest values of PUFA were obtained for C20:4 and C22:6, which were the main targets of reactive oxygen species (ROS) when parasitemia was higher than 1%. Similarly, plasma vitamins E and A were significantly reduced during the acute phase of malaria owing to their consumption in part as antioxidants. However, evaluation of the antioxidant enzymatic system in red blood cells of malaria patients indicated no significant difference from controls. Only superoxide dismutase activity tended to decrease when parasitemia increased. CONCLUSION: The results suggest that superoxide radicals are the main ROS produced during the acute phase of malaria, and that rejuvenation of RBC during hemolysis involving increased enzyme activities interacts to protect RBC from excessive superoxide radical production.

The place of electron spin resonance methods in the detection of oxidative stress in type 2 diabetes with poor glycemic control.

OBJECTIVE: Chronic production of reactive oxygen species (ROS) and/or deficiency in the antioxidant defense system are observed in non-insulin-dependent diabetes mellitus (NIDDM) patients. As an adjunct to the usual indirect parameters for evaluating oxidative stress, we assessed the feasibility of oxyradicals detection in venous blood by electron spin resonance spectroscopy (ESR). Detection of the ascorbate pool was also performed using the validated ESR analysis of the ascorbyl free radial (AFR)-dimethyl sulfoxide (DMSO) complex. METHODS AND RESULTS: Plasma lipoperoxidation was characterized by higher levels of total MDA (1.50 +/- 0.08 nmol/L), lower levels of GSH (0.54 +/- 0.02 mmol/L) and of vitamin A (2.13 +/- 0.52 mumol/L) in the NIDDM group than in the controls (0.75 +/- 0.05 nmol/L, 0.90 +/- 0.05 mmol/L, 3.52 +/- 1.04 mumol/L, respectively). Improvement of the ESR measurement of oxyradical adducts has been previously obtained by addition of a new sensitive nitrone (DEPMPO), which acts as a spin-trap. However, in our experiment the ESR signal-to-noise ratio was too low to detect significative oxyradicals adducts in total venous blood of NIDDM patients having a weak production of ROS. A significant difference (p < 0.002) was observed in DMSO/AFR index between controls (24.00 +/- 4.10 nmol/L) and NIDDM patients (7.28 +/- 2.36 nmol/L) suggesting ascorbate depletion related to the free radical production. CONCLUSION: The DMSO/AFR index could be an interesting additional marker of oxidative stress during a chronic production of ROS.

Fecal lipid chromatography--identification of an unusual fraction in relation to colon cancer.

The thin-layer chromatography of fecal lipids with revelation by phosphomolybdic reagent indicates the presence of an unusual fraction only in colon cancer patients. After isolation and identification, this fraction appears to be composed of coprostanol and its derivatives. The quantitative analysis of fecal neutral steroids in colon cancer patients compared to controls, patients with other digestive diseases and polypi shows a positive relationship between this fraction and colon cancer.

Discriminant analysis of urinary calculi by near-infrared reflectance spectroscopy.

Near-infrared reflectance analysis has been used to determine the qualitative and semi-quantitative composition of urinary calculi. This simple method requires calibration of the most common urinary calculi. Analysis time is short (less than 1 min) and only very small amounts of calculus in powder form (less than 100 micrograms) are required without the use of any reagent. Moreover, when compared to infrared spectroscopy, this method provides sufficient accuracy to identify mixed calculi containing two or three components, and permits semi-quantitative determinations. The speed and simplicity of this technique makes it a powerful method for the routine analysis of urinary calculi in clinical laboratories.

A compensatory mechanism improving red cell membrane fluidity in hemodialysed patients.

A fluorescence polarization technique with 1,6-diphenyl 1,3,5-hexatriene as a fluorescent probe was used to determine the fluidity of red cell membranes from hemodialysed patients before and after dialysis. After dialysis, there was a decrease in fluidity and activation energy values revealed a significantly changed distribution. The membrane lipid composition showed a significant increase in cholesterol after dialysis (p less than 0.001) and a significant reduction in saturated fatty acids (p less than 0.01) with an increase in unsaturated fatty acids (p less than 0.05). A compensatory mechanism could be suggested involving a reduction of saturated fatty acids in response to the increase in the cholesterol/phospholipid ratio. This could lead to an optimization of membrane fluidity.

Increase of erythrocyte resistance to hemolysis and modification of membrane lipids induced by hemodialysis.

Mechanical fragility, deformability and lipid composition of erythrocyte membranes were studied in 22 uremic dialysed patients before and after dialysis in comparison to controls. While deformability was not affected by a dialysis session, osmotic and saponin resistances to hemolysis were significantly increased after dialysis (p less than 0.001). The lipid composition of erythrocyte membranes was also altered during dialysis, with a notable increase in cholesterol and a different phospholipid distribution, i.e. phosphatidylcholine and sphingomyelin significantly decreased (p less than 0.001). Likewise, the fatty acid distribution showed large variations with an increase in polyunsaturated fatty acid. The acute effect of dialysis on the membrane lipid composition seems to be linked to erythrocyte alterations. Its significance is discussed in relation to the asymmetric transverse distribution of phospholipids previously described in human erythrocyte.

Association between antioxidant nutritional indicators and the incidence of dementia: results from the PAQUID prospective cohort study.

OBJECTIVE: To analyse the relation between antioxidant vitamins A, E, and malondialdehyde (MDA) lipoperoxidation product plasma concentrations with incident dementia. DESIGN: : A nested case-control within the PAQUID (Personnes Agées QUID) cohort. SETTING: The PAQUID population-based prospective cohort in southwestern France. SUBJECTS: Among 626 subjects with blood collection at baseline, 46 developed a dementia during the follow-up and were considered to be cases. Each case was matched (on age and sex) to three controls. RESULTS: Plasma vitamin E concentrations were lower among cases (mean value at 22.62 micromol/l (s.d.: 7.38) vs 24.99 (s.d.: 6.73 among controls). The same trend was observed for vitamin A concentrations, but the difference was not significant. On the contrary, MDA concentrations tended to be higher (mean value 1.35 micromol/l (s.d.: 0.53) vs 1.23 (s.d.: 0.44)) among cases. In logistic regression models, plasma values were split into tertiles. Adjusted for confounders, the risk of dementia was significantly increased in the lowest vitamin E tertile (< or =21.0 micromol/l) (OR=3.12, P=0.033) compared to the highest one (> or =25.5 micromol/l). The risk of Alzheimer's disease was also increased, with borderline significance (OR=3.06, P=0.053). Risks associated with vitamin A were nonsignificant. Similarly, there was a trend to an increased risk of dementia in the highest tertile of MDA (OR=1.67, P=0.31). CONCLUSIONS: These results suggest that subjects with low plasma vitamin E concentrations are at a higher risk of developing a dementia in subsequent years.

Lipoprotein(a) in 505 hospitalized patients with various pathological states: correlations with cardiovascular diseases and therapies.

OBJECTIVE: Our aim was to study the lipoprotein (a) (Lp(a)) levels in various pathological states. EXPERIMENTAL DESIGN: This investigation was prospective and included a healthy control group. SETTING: This study was carried out in two internal medicine and angiology services in teaching hospitals. PATIENTS: 505 patients were included with various diseases: 66 acute infections, 9 HIV infections, 25 cancers, 86 diabetes, 36 systemic diseases, 94 atheromatous vascular disease, 27 arterial hypertensions. A control group was composed of 21 healthy subjects. INTERVENTIONS: There was no therapeutic intervention but cardiovascular treatments were recorded. MEASURES: Serum Lp(a), total cholesterol, triglycerides, HDL-cholesterol, calculated LDL-cholesterol, apolipoproteins A-I and B were measured together with inflammatory parameters, serum creatinine, proteinuria, serum aminotransferase activity. RESULTS: There was no difference in Lp(a) levels between controls and each patient group. However, a correlation was found in systemic diseases between Lp(a) and C reactive protein (r = 0.371, p = 0.026) or serum albumin concentration (r = 0.453, p = 0.006). In hypertension, Lp(a) correlated with serum creatinine (r = 0.420, p = 0.03). In the whole patient population, Lp(a) was correlated with cholesterol (r = 0.156, p = 0.0001), apolipoprotein B (r = 0.215, p = 0.0001), age (r = 0.108, p = 0.015), arterial events (r = 0.174, p = 0.0001) and platelet anti-aggregant drugs (r = 0.169, p = 0.0001). CONCLUSIONS: Lp(a), was related to atheromatous events and in systemic diseases to inflammation, suggesting that Lp(a) might vary in some patients in a manner similar to acute phase proteins.

[In vivo study of the antilipoperoxidant effect of 3',5,7-trihydroxy-4'-methoxy flavone 7 rutinoside]. / Etude in vivo de l'effet antilipoperoxydant du 7 rutinoside de la 3',5,7-trihydroxy-4'-méthoxy flavone.

In 3-month-old Wistar rats carrageenan and CCl4 injected intraperitoneally induce an acute phase reaction which is characterized by a marked increase in alpha 1, alpha 2, beta serum globulins. This reaction corresponds to a large increase in these globulins in the first case and a smaller one in the second. A lipoperoxidant effect is demonstrated by the serum lipoprotein mobility as the lipoperoxidation index (in MDA units) or the decrease in serum vitamin A and E concentrations. This effect is also greater in the first case than in the second one. In the same way the lipoperoxidant effect is shown in liver microsomes but with a lower amplitude in the first case than in the second one. The treatment of rats by intraperitoneal injection of diosmine (150 mg/kg per week) during the 8 weeks which precede the injection of carrageenan or CCl4 results in: i) a marked decrease in the acute-phase reaction and a lower one in the lipoperoxidant effect, in serum; ii) a decrease in the CCl4 induced lipoperoxidant effect in liver microsomes. It may be concluded that diosmine, not injected at the same time as carrageenan or CCl4, but during the previous 8 weeks is sufficiently well distributed in the whole body to produce a marked inhibition of the acute phase reaction and a perceptible effect on lipoperoxidation. It may be considered an effective complement to the natural antioxidant defences of the organism (vitamins A and E).

[First observations on the main plasma parameters of oxidative stress in homozygous sickle cell disease]. / Premières observations sur les principaux paramètres plasmatiques du stress oxydatif chez le drépanocytaire homozygote.

The present study report 7 cases of sickle homozygous disease which have been analysed using markers of the oxidative-stress, 26 african male subjects were studied: 7 Hb SS subjects (age: m = 20) and 19 control subjects (Hb AA, age: m = 40). Plasma concentrations of F-MDA, T-MDA, TBARS, alpha tocopherol, retinol and beta carotene were measured. Plasma MDA and TBARS mean levels increased in sickle homozygous patients more than in controls. However, only TBARS mean concentrations were significantly increased between patients and controls: TBARS: 4.14 +/- 1.49 nMol/ml for Hb SS versus 2.10 +/- 1.21 nMol/ml for Hb AA (P less than 0.005). Vitamin A and vitamin E concentrations were significantly lower in Hb SS than in Hb AA. Beta carotene was significantly increased in patients vs controls. The significant increase of TBARS explains the great importance of the oxidative damage, whereas the significant decrease of vitamins A and E, may contribute, at least for a part, to maintain the autoxidation process or reveals its intensity in these patients.

[Oxidative stress and malaria. Apropos of 24 cases of Plasmodium falciparum malaria]. / Stress oxydatif et paludisme. A propos de 24 observations de paludisme à Plasmodium falciparum.

Oxidative stress has been suggested to be implicated in malaria. But it is not clear whether its major role is to kill intraerythrocytic parasites or to cause damage to host tissues. We have studied it in 24 European subjects hospitalized in Saint-André hospital, Bordeaux, France for Plasmodium falciparum access returning from a tropical trip, and in a group control of 16 subjects. Malondialdehyde, one of the oxidative stress markers is significantly increased in patients compared to the control group (m = 5.24 vs 2.14 mol/l). At the same time, it is observed a significative decrease in antioxidant factors, vitamin A and vitamin E. We found no relationship of the severity of malaria to the importance of the oxidative stress, and the question whether the oxidative stress attack host tissues or kill parasites remains entire. These observations should be completed by larger studies, particularly to improve malaria treatments available nowadays.