Sid Ahmed Merzouk

Abou Bakr Belkaid University of Tlemcen, Tlemsen, Tlemcen, Algeria

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Publications (17)34.39 Total impact

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    ABSTRACT: Background The aim of this investigation was to determine the in-vitro effects of linseed, olive and Nigel oils on T cell proliferation and function in gestational diabetes.Methods Blood samples were collected from 40 control healthy and 32 gestational diabetic mothers and their newborns. Peripheral blood lymphocytes were isolated using a density gradient of Ficoll. T cell proliferation, interleukin-2 and -4 (IL-2, IL-4) secretion, fatty acid composition and intracellular oxidative status were investigated.ResultsMitogen (Concanavalin A) stimulated lymphocyte proliferation, IL-2 secretion, intracellular reduced glutathione levels, SOD and catalase activities were lower while intracellular MDA and carbonyl proteins were higher in diabetic mothers and in their newborns as compared to their respective controls. Linseed oil induced a reduction in T-lymphocyte proliferation and IL-2 production, and alpha linolenic acid membrane enrichment in both diabetic and control groups. In the presence of Nigel oil, T-lymphocyte proliferation and IL-2 secretion, phospholipid linoleic and oleic acids were enhanced. Olive oil had no effect on lymphocyte proliferation in all groups. Linseed, olive and Nigel oils induced an increase in T cell levels of reduced glutathione levels and in activities of catalase and SOD with a concomitant decrease in MDA and carbonyl protein contents.Conclusion Linseed, olive and Nigel oils had beneficial effects on T cell functions in gestational diabetes.
    Journal of Diabetes 08/2014; · 2.94 Impact Factor
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    ABSTRACT: The aim of this work was to determine the effect of dietary n - 3 PUFA on oxidant/antioxidant status, in vitro very low and low density lipoprotein (VLDL-LDL), and VLDL-LDL-fatty acid composition in macrosomic pups of diabetic mothers. We hypothesized that n - 3 PUFA would improve oxidative stress in macrosomia. Diabetes was induced in female Wistar rats fed with the ISIO diet (control) or with the EPAX diet (enriched in n - 3 PUFAs), by streptozotocin. The macrosomic pups were killed at birth (day 0) and at adulthood (day 90). Lipid parameters and VLDL-LDL-fatty acid composition were investigated. The oxidant/antioxidant status was determined by measuring plasma oxygen radical absorbance capacity (ORAC), hydroperoxides, carbonyl proteins, and VLDL-LDL oxidation. Macrosomic rats of ISIO fed diabetic mothers showed an increase in plasma and VLDL-LDL-triglycerides and VLDL-LDL-cholesterol levels and altered VLDL-LDL-fatty acid composition. Plasma ORAC was low with high hydroperoxide and carbonyl protein levels. The in vitro oxidizability of VLDL-LDL was enhanced in these macrosomic rats. The EPAX diet corrected lipid parameters and improved oxidant/antioxidant status but increased VLDL-LDL susceptibility to oxidation. Macrosomia is associated with lipid abnormalities and oxidative stress. n - 3 PUFA exerts favorable effects on lipid metabolism and on the oxidant/antioxidant status of macrosomic rats. However, there are no evident effects on VLDL-LDL oxidation.
    BioMed Research International 01/2014; 2014:368107. · 2.71 Impact Factor
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    ABSTRACT: Objective To determine oxidative stress markers in maternal obesity during pregnancy and to evaluate feto-placental unit interaction, especially predictors of fetal metabolic alterations. Patients and methods 40 obese pregnant women (prepregnancy BMI > 30 kg/m²) were compared to 50 control pregnant women. Maternal, cord blood and placenta samples were collected at delivery. Biochemical parameters (total cholesterol and triglycerides) and oxidative stress markers (malondialdehyde, carbonyl proteins, superoxide anion expressed as reduced Nitroblue Tetrazolium, nitric oxide expressed as nitrite, reduced glutathione, catalase, superoxide dismutase) were assayed by biochemical methods. Results Maternal, fetal and placental triglyceride levels were increased in obese group compared to control. Maternal malondialdehyde, carbonyl proteins, nitric oxide and superoxide anion levels were high while reduced glutathione concentrations and superoxide dismutase activity were low in obesity. In the placenta and in newborns of these obese mothers, variations of redox balance were also observed indicating high oxidative stress. Maternal and placental interaction constituted a strong predictor of fetal redox variations in obese pregnancies. Discussion Maternal obesity compromised placental metabolism and antioxidant status which strongly impacted fetal redox balance. Oxidative stress may be one of the key downstream mediators that initiate programming of the offspring. Conclusion Maternal obesity is associated with metabolic alterations and dysregulation of redox balance in the mother- placenta – fetus unit. These perturbations could lead to maternal and fetal complications and should be carefully considered.
    Placenta 01/2014; · 3.12 Impact Factor
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    Amina Ayad, Hafida Merzouk, Sid Ahmed Merzouk, Michel Narce
    Biomedical and Environmental Sciences 09/2013; 26(9):765-768. · 1.15 Impact Factor
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    ABSTRACT: In this study, plasma lipids, lipoproteins and markers of oxidant/antioxidant status were investigated in young (n = 45) and older (n = 40) obese men and compared to those in young (n = 65) and older (n = 55) normal weight controls. The purpose was to determine whether obesity exacerbates or not lipid, lipoprotein abnormalities and oxidative stress in older men. Our findings showed that all obese patients had increased plasma triglyceride, cholesterol, LDL-cholesterol, -triglyceride and HDL-triglyceride levels concentrations compared to controls (P < 0.01). However, the younger obese men had relatively larger and accentuated changes in plasma lipids and lipoproteins than the older patients. Additionally, total antioxidant capacity (ORAC), vitamins C and E were lower while hydroperoxides and carbonyl proteins were higher in young and older obese patients compared to their respective controls (P < 0.001). Erythrocyte antioxidant SOD and catalase activities were enhanced in obese young patients, but reduced in obese older men. Glutathione peroxidase activity was low in obesity irrespective of age. In multiple regression analysis, BMI significantly predicted total cholesterol, LDL-C, LDL-TG and HDL-TG (P < 0.0001). These relationships were not modified by age. BMI alone was a not a significant predictor for ORAC, vitamins C, E, catalase and Glutathione peroxidase. However, the interaction BMI-age significantly predicted these parameters and explained 28-45% of their changes. BMI was a significant predictor of SOD, carbonyl proteins and hydroperoxides. This effect became more significant (P < 0.0001) and worsened with BMI-age interaction. In conclusion, lipoprotein metabolism and oxidant/antioxidant status are altered in obesity irrespective of age. However, obesity-related lipid and lipoprotein alterations were attenuated while oxidative stress was aggravated in older adults.
    Nutrition, metabolism, and cardiovascular diseases: NMCD 10/2011; 21(10):792-9. · 3.52 Impact Factor
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    ABSTRACT: Background: Obesity has reached epidemic proportions world-wide. Its risk factors are poorly studied, especially among children in developing countries such as Algeria.Objectives: The purpose of this study was therefore to determine the prevalence and risk factors of obesity in Algerian schoolchildren 6 to 8 years aged by conducting a school-site retrospective cohort study in Tlemcen Department (western Algeria).Material and Mthods: From 2008 to 2010, socio-demographic characteristics, body mass index (BMI), physical activity categories, lifestyle and nutritional habits of 1520 children (839 boys and 681 girls), at entrance into primary school, were recorded using a self-administered questionnaire.Results: Among the 1520 participants, 99 (6.5%) were obese. Birthweight ≤ 2.5 kg and ≥ 4 kg, early introduction of solid foods and low physical activity were significantly associated with obesity (p<0.001). Additionally, mother's and grandmother's BMI ≥30 kg/m(2), fewer children in the household, higher parental education, household income and the presence of familial obesity may predispose significantly to childhood obesity (p<0.001). Furthermore, child's BMI was significant positively correlated with total energy, fat and saturated fatty acid (SFA) intakes (p<0.01). Mother's and grandmother's BMI were significant positively correlated with child total energy, fat and SFA intakes. Physical activity score was significant negatively correlated with child total energy, fat and SFA (p<0.01) intakes in obese children.Conclusions: Mother's and grandmother's obesity, excess energy and fat intakes and low physical activity are the strong predictors of childhood obesity in Algeria. Preventive measures should focus on the promotion of physical activity and maternal and children nutritional education.
    Mædica. 04/2011; 6(2):90-9.
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    ABSTRACT: Pesticides have been shown to possess marked immunotropic activity. The aim of this work was to study the in vitro effects of different concentrations (1–100μM) of Mancozeb (fungicide) and Metribuzin (herbicide), on the proliferative responses of human and rat spleen lymphocytes stimulated by concanavalin A (ConA, mitogen), the Th1- (IL-2, INFγ) and Th2- (IL-4) cytokine secretion and on the intracellular oxidative status. The results showed that Mancozeb significantly reduced ConA lymphocyte proliferation in a dose-dependent manner in both humans and rats. It also decreased IL-2, INFγ and IL-4 secretion with a a shift away to Th1 phenotype. Metribuzin at low concentrations (1–10μM) resulted in activation of ConA stimulated lymphocyte proliferation and cytokine production in both human and rat spleen cells. However, at high concentrations (25–100μM), Metribuzin induced a dose-dependent inhibition of lymphocyte proliferation and cytokines. Changes in intracellular levels of reduced Glutathione, hydroperoxides and carbonyl proteins and in the activities of catalase and SOD were observed after Mancozeb and Metribuzin exposure reflecting oxidative stress and DNA damage specially at high concentrations.In conclusion, Mancozeb and Metribuzin had significant immunomodulatory properties with oxidative stress induction at high concentrations.
    Pesticide Biochemistry and Physiology - PESTIC BIOCHEM PHYSIOL. 01/2011; 101(1):27-33.
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    ABSTRACT: The combined effects of developmental programming and high-fat feeding at weaning on fatty acid metabolism of the offspring are not well known. In the present study, we aim at characterizing the influence of maternal and offspring's own diets on liver and very low-density lipoprotein (VLDL) lipids; fatty acid profiles of VLDL and liver phospholipids, triglycerides, and cholesteryl esters; and hepatic enzyme activities. Twenty obese male rats born to cafeteria diet-fed dams and 20 control rats born to control diet-fed dams were selected. At weaning, 10 rats of each group were fed control or cafeteria diet. Obese rats had a significant increase in serum glucose, insulin, leptin, VLDL apolipoprotein B100 and lipid levels, and hepatic fatty acid synthase and a reduction in acyl-coenzyme A oxidase and dehydrogenase activities compared with control pups at day 21 and day 90. Hepatic steatosis was apparent only at day 90. The proportions of saturated fatty acids and monounsaturated fatty acids and the oleic to stearic acid ratio were significantly increased, whereas polyunsaturated fatty acids and the arachidonic to linoleic acid ratio were decreased, in liver and VLDL lipids of obese pups compared with controls. The cafeteria diet at weaning induced more severe abnormalities in obese rats. In conclusion, maternal cafeteria diet induced a permanent reduction in hepatic β-oxidation and an increase in hepatic lipogenesis that caused liver steatosis and VLDL and fatty acid alterations in adult offspring. These preexisting alterations in offspring were worsened under a high-fat diet from weaning to adulthood. Nutritional recommendations in obesity must then target maternal and postnatal nutrition, especially fatty acid composition.
    Metabolism: clinical and experimental 12/2010; 59(12):1701-9. · 3.10 Impact Factor
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    ABSTRACT: To show that lipid and lipoprotein levels and cell sodium and potassium content and transport could change depending on the degree of hypertension. Forty-three hypertensive patients and 20 healthy subjects were recruited at the Cardiology and Biochemistry Departments of Tlemcen University Hospital Centre (Northwest of Algeria). Levels of CHOL, TG, PL, HDL-TG, LDLc, LDL-TG, LDL-PL, HDL2-TG and HDL3-TG were significantly higher in hypertensive patients than those in controls. HDL-PL levels were significantly lower in patients compared with controls and decreased according to the grade of hypertension. HDL2c, HDL2-PL and HDL3-TG and cell content and fluxes of sodium and potassium change gradually with higher grades of hypertension. Hypertensive patients with circulating lipid alterations are associated to ion cell content and transport abnormalities, which were worsened progressively with higher grade of hypertension.
    Clinical biochemistry 08/2010; 43(12):942-7. · 2.02 Impact Factor
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    ABSTRACT: This study was carried out to determine the relationships between leptin concentrations, lipid alterations, oxidant/ antioxidant status, in vitro LDL oxidizability and LDL-fatty acid composition in overweight breast cancer patients. Glucose, insulin, leptin, lipids, LDL-cholesteryl ester fatty acids, markers of oxidant status (MDA, Hydroperoxides, carbonyl proteins, conjugated dienes) and markers of antioxidant status (vitamins A, C, E, erythrocyte activities of the enzymes superoxide dismutase, SOD, catalase, glutathione peroxidase,GPx, and glutathione reductase, GR and the serum total antioxidant status, ORAC) were investigated in breast cancer patients and in control women. Our findings showed that insulin, leptin, triglyceride, cholesterol and LDL-C concentrations were increased in patients compared to controls. ORAC and vitamin C and E values were lower while plasma hydroperoxide, carbonyl protein and conjugated diene levels, SOD and GPx activities were higher than in controls. Alterations in LDL-fatty acid composition were associated with their enhanced oxidative susceptibility. There were significant positive correlations between leptin concentrations and LDL-C, hydroperoxides, carbonyl proteins, SOD activity, baseline conjugated diene levels and oxidation rate, and significant negative correlations between leptin and ORAC, lag time and LDL-PUFA in patients. In conclusion, breast cancer is associated with lipid alterations and enhanced oxidative stress linked to high leptin levels in overweight.
    Pathology & Oncology Research 10/2009; 16(2):159-67. · 1.56 Impact Factor
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    ABSTRACT: The aim of this study is to determine the oxidant and antioxidant status in Algerian mothers and their newborns according to birth weight. Subjects for the study were consecutively recruited from Tlemcen hospital. 139 pregnant women and their newborns were included. The plasma total antioxidant activity (ORAC), vitamins A, C, E, hydroperoxides, carbonyl proteins, and erythrocyte antioxidant enzyme activities (catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase) were measured on mothers and their newborns. Lipid and lipoprotein parameters were also determined. The results were assessed in accordance with small for gestational age (SGA), appropriate (AGA) and large (LGA) birth weight of the newborn. SGA newborns and their mothers had low ORAC, vitamin C and E values (P<0.01) and high plasma hydroperoxide and carbonyl protein levels (P<0.01) compared to AGA groups. The SGA group showed also altered erythrocyte antioxidant enzyme activities and several lipid and lipoprotein changes. In LGA compared to control newborns, hydroperoxide, carbonyl protein levels and SOD activity were enhanced while ORAC, vitamin A and E levels were reduced. However, oxidant and antioxidant status in their mothers was similar to that in control mothers. Oxidative stress is present in both SGA and LGA newborns, with a concomitant alteration in maternal oxidant and antioxidant status only in intrauterine growth restriction.
    European journal of obstetrics, gynecology, and reproductive biology 09/2008; 141(2):95-9. · 1.97 Impact Factor
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    ABSTRACT: In this work, we assessed the in-vitro effects of eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) (final concentration, 15 microM) on T cell blastogenesis, interleukin-2 and -4 (IL-2, IL-4) secretion, fatty acid composition and intracellular oxidative status in type I diabetic patients with or without complications. Con A stimulated lymphocyte proliferation, glucose uptake, intracellular reduced glutathione levels and catalase activity were lower in diabetics as compared to controls, regardless to the presence of complications. EPA and DHA diminished T-lymphocyte proliferation and IL-2 production but enhanced IL-4 secretion in both diabetic and control groups. No changes in the levels of reduced glutathione and in the activities of catalase and SOD were observed in control T cells cultured in the presence of EPA and DHA. However, in diabetic patients, addition of n-3 PUFA to culture induced an increase in T cell levels of reduced glutathione and hydroperoxide, and in activities of catalase and SOD. Low levels of arachidonic acid (C20:4n-6) were found in plasma membrane phospholipids of lymphocytes from diabetic patients compared to controls. Incubation of lymphocytes with EPA and DHA was associated with an incorporation of these fatty acids in membrane phospholipids. In conclusion, the beneficial effects of n-3 PUFA on T cell functions in type I diabetes could be attributed to their suppressive action and modulation of cytokine secretion, and to the improvement of intracellular oxidative status.
    Lipids 07/2008; 43(6):485-97. · 2.56 Impact Factor
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    ABSTRACT: The aim of this study was to determine serum lecithin:cholesterol acyltransferase (LCAT) activity in parallel with HDL2 and HDL3 amounts and composition in pregnancy induced hypertension (PIH) and chronic hypertensive (CH) mothers and in their small for gestational age (SGA) newborns. LCAT activity was assayed by conversion of [3H] cholesterol to labelled cholesteryl ester. HDL2 and HDL3 were separated by ultracentrifugation. At term, cholesterol values were similar in PIH, CH and controls. However, higher levels of triglycerides were observed in PIH and CH (+20% and +21%, respectively) as compared with normotensive control mothers (NC). HDL2 and HDL3-phospholipids, HDL2-cholesterol concentrations and LCAT activity were lower in PIH and CH mothers than in NC mothers. Similar changes were also observed in SGA newborns of PHI mothers and in SGA newborns of CH mothers when compared to appropriate for gestational age newborns of control mothers (AGA-NC). In addition, SGA newborns showed low HDL2 and HDL3 apoA-I contents. Maternal hypertension and foetal intrauterine growth retardation are associated with profound abnormalities in HDL metabolism, consistent with an atherogenic risk. SGA lipoprotein profiles appear to implicate later metabolic diseases.
    European Journal of Pediatrics 06/2008; 167(5):525-32. · 1.98 Impact Factor
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    ABSTRACT: The effects of dietary n-3 polyunsaturated fatty acids on lipoprotein concentrations and on lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL) and lecithin cholesterol acyltransferase (LCAT) activities were studied in streptozotocin-induced diabetic rats during pregnancy and in their macrosomic offspring from birth to adulthood. Pregnant diabetic and control rats were fed Isio-4 diet (vegetable oil) or EPAX diet (concentrated marine omega-3 EPA/DHA oil), the same diets were consumed by pups at weaning. Compared with control rats, diabetic rats showed, during pregnancy, a significant elevation in very low density lipoprotein (VLDL) and low and high density lipoprotein (LDL-HDL(1))-triglyceride, cholesterol and apoprotein B100 concentrations and a reduction in apoprotein A-I levels. HTGL activity was high while LPL and LCAT activities were low in these rats. The macrosomic pups of Isio-4-fed diabetic rats showed a significant enhancement in triglyceride and cholesterol levels at birth and during adulthood with a concomitant increase in lipase and LCAT activities. EPAX diet induces a significant diminution of VLDL and LDL-HDL(1) in mothers and in their macrosomic pups, accompanied by an increase in cholesterol and apoprotein A-I levels in HDL(2-3) fraction. It also restores LPL, HTGL and LCAT activities to normal range. EPAX diet ameliorates considerably lipoprotein disorders in diabetic mothers and in their macrosomic offspring.
    General Physiology and Biophysics 04/2008; 27(1):3-11. · 0.85 Impact Factor
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    ABSTRACT: We investigated the role of dietary n-3 polyunsaturated fatty acids (n-3 PUFA) in the modulation of total antioxidant status in streptozotocin (STZ)-induced diabetic rats and their macrosomic offspring. Female wistar rats, fed on control diet or n-3 PUFA diet, were rendered diabetic by administration of five mild doses of STZ on day 5 and were killed on days 12 and 21 of gestation. The macrosomic (MAC) pups were killed at the age of 60 and 90 days. Lipid peroxidation was measured as the concentrations of plasma thiobarbituric acid reactive substances (TBARS), and the total antioxidant status was determined by measuring (i) plasma oxygen radical absorbance capacity (ORAC), (ii) plasma vitamin A, E and C concentrations, and (iii) antioxidant enzymes activities in erythrocytes. The plasma lipid concentrations and fatty acid composition were also determined. Diabetes increased plasma triglyceride and cholesterol concentrations, whereas macrosomia was associated with enhanced plasma cholesterol and triglyceride levels, which diminished by feeding n-3 PUFA diet. N-3 PUFA diet also reduced increased plasma TBARS and corrected the decreased ORAC values in diabetic rats and their macrosomic offspring. EPAX diet increased the diminished vitamin A levels in diabetic mothers and vitamin C concentrations in macrosomic pups. Also, this diet improved the decreased erythrocyte superoxide dismutase and glutathione peroxidase activities in diabetic and macrosomic animals. Diabetes and macrosomia were associated with altered lipid metabolism, antioxidant enzyme activities and vitamin concentrations. N-3 PUFA diet improved hyperlipidemia and restored antioxidant status in diabetic dams and MAC offspring.
    International Journal of Obesity 06/2006; 30(5):739-50. · 5.22 Impact Factor
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    ABSTRACT: This study was carried out to determine the relationships between oxidant/antioxidant status, in vitro LDL oxidizability and LDL-fatty acid composition in diabetes mellitus. Plasma total antioxidant capacity (oxygen radical absorbance capacity, ORAC) and LDL-cholesteryl ester fatty acids were investigated in type 1 and type 2 diabetic subjects with and without complications. The degree of LDL oxidation was determined by the measurement of hydroperoxide levels before and after in vitro peroxidative stress with CuSO4. ORAC values were decreased in diabetic subjects who showed high basal hydroperoxide levels. Oxidizability of LDL in these subjects was higher than in control subjects and it was unrelated to LDL-fatty acid composition. However, in type 2 diabetic subjects with complications, alterations in LDL-fatty acid composition were associated with their enhanced oxidative susceptibility. LDL-fatty acid alterations might be an additional factor that influences LDL oxidizability especially in type 2 diabetes. In conclusion, diabetes mellitus is associated with enhanced oxidative stress and defective antioxidant/oxidant balance regardless the type of diabetes and presence of complications.
    General Physiology and Biophysics 01/2005; 23(4):387-99. · 0.85 Impact Factor
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    ABSTRACT: Plasma vitamin A, C and E levels and erythrocyte antioxidant enzyme activities were investigated in type I and type II diabetic subjects with and without complications, i.e., hypertension, coronary artery disease and renal failure. Reverse phase HPLC was used to quantify vitamin A and E levels. We observed that the vitamin C levels were not significantly different between control and diabetic subjects. However, vitamin A and E levels were significantly lower in type I and type II diabetic subjects compared to controls. Superoxide dismutase (SOD) activity was significantly lower in type II, but not in type I, diabetic patients compared to controls. Interestingly, glutathione reductase and peroxidase activities were diminished in type I, but not in type II, diabetic subjects as compared to controls. Catalase activity was lower in both types of diabetic patients in comparison with their respective controls. Altogether these results suggest that diabetes mellitus may be associated with altered antioxidant status regardless to various complications.
    General Physiology and Biophysics 04/2003; 22(1):15-27. · 0.85 Impact Factor

Publication Stats

156 Citations
34.39 Total Impact Points

Institutions

  • 2003–2014
    • Abou Bakr Belkaid University of Tlemcen
      • • Département des Sciences et Techniques
      • • Département de Biologie
      • • Faculté des Sciences
      • • Département de Physique
      Tlemsen, Tlemcen, Algeria
  • 2009
    • Université des Sciences et de la Technologie d'Oran Mohamed Boudiaf
      Wahrān, Oran, Algeria
  • 2006
    • University of Burgundy
      Dijon, Bourgogne, France