ascorbic-acid and Metabolic-Syndrome

ascorbic-acid has been researched along with Metabolic-Syndrome* in 40 studies

Reviews

5 review(s) available for ascorbic-acid and Metabolic-Syndrome

ArticleYear
Vitamin C: A Review on its Role in the Management of Metabolic Syndrome.
    International journal of medical sciences, 2020, Volume: 17, Issue:11

    Topics: Animals; Antioxidants; Ascorbic Acid; Humans; Inflammation; Metabolic Syndrome; Oxidative Stress

2020
The relationship between vitamin C status, the gut-liver axis, and metabolic syndrome.
    Redox biology, 2019, Volume: 21

    Metabolic syndrome (MetS) is a constellation of cardiometabolic risk factors, which together predict increased risk of more serious chronic diseases. We propose that one consequence of dietary overnutrition is increased abundance of Gram-negative bacteria in the gut that cause increased inflammation, impaired gut function, and endotoxemia that further dysregulate the already compromised antioxidant vitamin status in MetS. This discussion is timely because "healthy" individuals are no longer the societal norm and specialized dietary requirements are needed for the growing prevalence of MetS. Further, these lines of evidence provide the foundational basis for investigation that poor vitamin C status promotes endotoxemia, leading to metabolic dysfunction that impairs vitamin E trafficking through a mechanism involving the gut-liver axis. This report will establish a critical need for translational research aimed at validating therapeutic approaches to manage endotoxemia-an early, but inflammation-inducing phenomenon, which not only occurs in MetS, but is also prognostic of more advanced metabolic disorders including type 2 diabetes mellitus, as well as the increasing severity of nonalcoholic fatty liver diseases.

    Topics: Animals; Antioxidants; Ascorbic Acid; Endotoxemia; Gastrointestinal Tract; Humans; Liver; Metabolic Syndrome; Oxidants; Oxidation-Reduction; Oxidative Stress; Prevalence; Vitamin E

2019
Update on Importance of Diet in Gout.
    The American journal of medicine, 2016, Volume: 129, Issue:11

    Gout is an inflammatory arthritis caused by deposition of monosodium urate crystals within synovial joints. Although it is most well-known for its arthritis, gout has an intimate relationship with many other cardiovascular and metabolic conditions. Current recommendations support aggressive medical therapy to treat gout, whereas dietary counseling has become less emphasized. This article argues for the absolute importance of dietary counseling in gout and proves why this counseling may impact the long term well-being of a patient with gout.

    Topics: Alcohol Drinking; Ascorbic Acid; Carbonated Beverages; Coffee; Dairy Products; Diet Therapy; Disease Progression; Gout; High Fructose Corn Syrup; Humans; Hyperuricemia; Metabolic Syndrome; Purines; Tea; Vitamins

2016
The fetal origins of the metabolic syndrome: can we intervene?
    Journal of pregnancy, 2012, Volume: 2012

    Epidemiological studies have suggested that metabolic programming begins during fetal life and adverse events in utero are a critical factor in the etiology of chronic diseases and overall health. While the underlying molecular mechanisms linking impaired fetal development to these adult diseases are being elucidated, little is known about how we can intervene early in life to diminish the incidence and severity of these long-term diseases. This paper highlights the latest clinical and pharmaceutical studies addressing how dietary intervention in fetal and neonatal life may be able to prevent aspects of the metabolic syndrome associated with IUGR pregnancies.

    Topics: Antioxidants; Ascorbic Acid; Diet Therapy; Dietary Supplements; Exenatide; Fatty Acids, Omega-3; Female; Fetal Growth Retardation; Folic Acid; Humans; Hypoglycemic Agents; Melatonin; Metabolic Syndrome; Micronutrients; Peptides; Pregnancy; Prenatal Exposure Delayed Effects; Prenatal Nutritional Physiological Phenomena; Resveratrol; Stilbenes; Venoms

2012
Lessons from comparative physiology: could uric acid represent a physiologic alarm signal gone awry in western society?
    Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology, 2009, Volume: 179, Issue:1

    Uric acid has historically been viewed as a purine metabolic waste product excreted by the kidney and gut that is relatively unimportant other than its penchant to crystallize in joints to cause the disease gout. In recent years, however, there has been the realization that uric acid is not biologically inert but may have a wide range of actions, including being both a pro- and anti-oxidant, a neurostimulant, and an inducer of inflammation and activator of the innate immune response. In this paper, we present the hypothesis that uric acid has a key role in the foraging response associated with starvation and fasting. We further suggest that there is a complex interplay between fructose, uric acid and vitamin C, with fructose and uric acid stimulating the foraging response and vitamin C countering this response. Finally, we suggest that the mutations in ascorbate synthesis and uricase that characterized early primate evolution were likely in response to the need to stimulate the foraging "survival" response and might have inadvertently had a role in accelerating the development of bipedal locomotion and intellectual development. Unfortunately, due to marked changes in the diet, resulting in dramatic increases in fructose- and purine-rich foods, these identical genotypic changes may be largely responsible for the epidemic of obesity, diabetes and cardiovascular disease in today's society.

    Topics: Animals; Antioxidants; Ascorbic Acid; Blood Pressure; Evolution, Molecular; Fasting; Fructose; Gout; Humans; Inflammation Mediators; Insulin Resistance; Metabolic Syndrome; Models, Biological; Starvation; Urate Oxidase; Uric Acid; Weight Gain

2009

Trials

10 trial(s) available for ascorbic-acid and Metabolic-Syndrome

ArticleYear
The Consumption of Beef Burgers Prepared with Wine Grape Pomace Flour Improves Fasting Glucose, Plasma Antioxidant Levels, and Oxidative Damage Markers in Humans: A Controlled Trial.
    Nutrients, 2018, Oct-01, Volume: 10, Issue:10

    Wine grape pomace flour (WGPF) is a fruit byproduct that is high in fiber and antioxidants. We tested whether WGPF consumption could affect blood biochemical parameters, including oxidative stress biomarkers. In a three-month intervention study, 27 male volunteers, each with some components of metabolic syndrome, consumed a beef burger supplemented with 7% WGPF containing 3.5% of fiber and 1.2 mg gallic equivalents (GE)/g of polyphenols (WGPF-burger), daily, during the first month. The volunteers consumed no burgers in the second month, and one control-burger daily in the third month. At baseline and after these periods, we evaluated the metabolic syndrome components, plasma antioxidant status (i.e., 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH), vitamin E, vitamin C), and oxidative damage markers (i.e., advanced oxidation protein products (AOPPs), oxidized low-density lipoproteins (oxLDLs), malondialdehyde (MDA)). The WGPF-burger intake significantly reduced glycemia and homeostatic model assessment-based measurement of insulin resistance. Vitamin C increased and decreased during the consumption of the WGPF-burger and control-burger, respectively. The WGPF-burger intake significantly decreased AOPP and oxLDL levels. Vitamin E and MDA levels showed no significant changes. In conclusion, the consumption of beef burgers prepared with WGPF improved fasting glucose and insulin resistance, plasma antioxidant levels, and oxidative damage markers. Therefore, this functional ingredient has potential as a dietary supplement to manage chronic disease risk in humans.

    Topics: Adult; Advanced Oxidation Protein Products; Antioxidants; Ascorbic Acid; Blood Glucose; Dietary Fiber; Dietary Supplements; Eating; Fasting; Flour; Humans; Insulin Resistance; Lipoproteins, LDL; Longitudinal Studies; Male; Malondialdehyde; Metabolic Syndrome; Middle Aged; Postprandial Period; Red Meat; Vitamin E; Vitis

2018
[Physical activity in patients with symptoms of metabolic syndrome reduces the concentration of plasma antioxidant vitamins - protective effect of vitamin C].
    Polski merkuriusz lekarski : organ Polskiego Towarzystwa Lekarskiego, 2015, Volume: 38, Issue:227

    Patients with cardiovascular diseases, including those with the symptoms of metabolic syndrome (MS), are recommended regular exercise but many studies indicate its role in the production of reactive oxygen species. Vitamin C supplementation may enhance the antioxidant barrier in MS patients.. The aim of the study was to assess the impact of regular physical activity (PA)and vitamin C supplementation on plasma vitamin A, C and E levels in patients with MS.. The study included 62 patients with MS according to International Diabetes Federation criteria, 32 men and 30 women, aged 38-57 years (mean age 51,24 ± 5,29 years). The patients were divided in two groups: group I (MS+PA) - 31 patients with recommended regular physical activity; group II ( MS+PA+C) - 31 patients with recommended regular physical activity and vitamin C supplementation per os. The control group consisted of 23 healthy individuals without MS, 17 men and 6 women, aged 49-56 years (mean age 53,21 ± 3,6 years), who were not recommended any vitamin supplementation nor physical activity. Plasma vitamin A, C and E levels were estimated in MS patients with spectrophotometry using T60V spectrophotometer (PG Instruments) before and after regular exercise with and without vitamin C supplementation. In the control group plasma levels of antioxidant vitamins were assessed only once.. The plasma vitamin A, C and E levels were significantly lower (p<0,05) in MS patients than in the control group. After 6 weeks of regular physical activity a significant fall in plasma levels of antioxidant vitamins was observed in MS patients. In the group of patients with regular physical activity and vitamin C supplementation there was detected a significant rise in the level of all the tested vitamins close to the levels in control group.. Regular physical activity enhances the decrease in plasma antioxidant vitamin level in patients with MS. Vitamin C supplementation conducted in parallel with regular physical activity normalize plasma vitamin A, C and E levels in these patients.

    Topics: Adult; Antioxidants; Ascorbic Acid; Dietary Supplements; Exercise; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Vitamin A; Vitamin E

2015
The Dietary Approaches to Stop Hypertension (DASH) diet affects inflammation in childhood metabolic syndrome: a randomized cross-over clinical trial.
    Annals of nutrition & metabolism, 2014, Volume: 64, Issue:1

    The effects of the DASH (Dietary Approaches to Stop Hypertension) diet on inflammation in childhood metabolic syndrome (MetS) have still to be identified.. To examine the effects of the DASH diet on markers of systemic inflammation in adolescents with MetS.. In this randomized, cross-over clinical trial, 60 postpubescent girls with MetS were randomly assigned to receive either the DASH diet menu cycles or usual dietary advice (UDA) for 6 weeks. After a 4-week washout period, participants were crossed over to the alternate arm. The DASH diet was designed to maintain the current body weight. This diet contained high amounts of fruit, vegetables and low-fat dairy products and was low in saturated fats and cholesterol. UDA consisted of general oral advice and written information about healthy food choices based on the Healthy Eating Plate. Compliance to the DASH diet was assessed through quantification of plasma vitamin C levels. Fasting venous blood samples were taken 4 times from each participant: at baseline and at the end of each study arm. Circulating levels of biomarkers of systemic inflammation were quantified according to standard protocols.. Mean (SD) age and weight of participants was 14.2 years (1.7) and 69 kg (14.5), respectively. Serum vitamin C levels tended to increase during the DASH phase compared with the UDA phase (16.8 ± 12.9 vs. -13.8 ± 9.7 ng/dl, respectively, p = 0.06) indicating a relatively good compliance to the DASH diet. Adherence to the DASH diet, compared to the UDA, had a significant effect on serum high-sensitivity C-reactive protein levels (p = 0.002). This effect remained significant even after adjustment for weight changes and after further controlling for changes in lipid profiles. We did not observe any significant effect of intervention on levels of serum tumor necrosis factor-alpha, interleukin (IL)-2, IL-6 and adiponectin, in either the crude or adjusted models. There were no significant group*time interactions for any dependent variable, except for IL-6; this was close to the significant level.. In summary, consumption of the DASH eating pattern for 6 weeks may reduce circulating levels of hs-CRP among adolescents with MetS. Other inflammatory markers were not affected by the DASH diet.

    Topics: Adiponectin; Adolescent; Ascorbic Acid; Biomarkers; Body Weight; C-Reactive Protein; Child; Cross-Over Studies; Dairy Products; Diet; Fatty Acids; Female; Fruit; Humans; Inflammation; Interleukin-2; Interleukin-6; Metabolic Syndrome; Motor Activity; Tumor Necrosis Factor-alpha; Vegetables

2014
[Estimation of plasma vitamin A, C and E levels in patients with metabolic syndrome].
    Polski merkuriusz lekarski : organ Polskiego Towarzystwa Lekarskiego, 2014, Volume: 36, Issue:215

    Metabolic syndrome (MS) is a coexistence of metabolic risk factors affecting development of cardiovascular diseases. In the pathogenesis of MS there participate reactive oxygen species which are excessively produced in such elements of MS as hyperglycemia, insulin resistance and obesity. Vitamins A, C and E are an important part of the non-enzymatic antioxidative barrier in humans. The aim of the study was to estimate plasma vitamin A, C and E levels in patients with symptoms of MS.. The study included 68 patients with symptoms of MS according to International Diabetes Federation criteria (2005), 37 men and 31 women, aged 34-65 years (mean age 57, 76 +/- 8, 29 years). The control group consisted of 24 healthy individuals without MS, 18 men and 6 women, aged 49-67 (mean age 58, 5 +/- 5, 6 years). Plasma vitamin A, C and E levels were estimated in patients and the control group with spectrophotometry using T60V spectrophotometer (PG Instruments).. The plasma vitamin A, C and E levels were significantly lower (p < 0.05) in MS patients than in the healthy individuals without symptoms of MS. The most significant differences in the level of antioxidative vitamins in both groups were related to vitamin C and vitamin E.. The decreased level of vitamins A, C and E points to the weakening of antioxidative barrier in patients with MS.

    Topics: Adult; Aged; Antioxidants; Ascorbic Acid; Cholesterol, HDL; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Vitamin A; Vitamin E

2014
Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.
    American journal of physiology. Heart and circulatory physiology, 2014, Sep-15, Volume: 307, Issue:6

    We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise - rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P < 0.01) and a greater reduction in MRT with AA infusion (r = -0.43, P = 0.02). We concluded that AA infusion during moderate-intensity, rhythmic forearm exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA.

    Topics: Adolescent; Adult; Antioxidants; Arterial Pressure; Ascorbic Acid; Biomarkers; Blood Flow Velocity; Brachial Artery; C-Reactive Protein; Exercise; Female; Forearm; Humans; Inflammation Mediators; Infusions, Intra-Arterial; Male; Metabolic Syndrome; Obesity; Regional Blood Flow; Time Factors; Vasodilation; Young Adult

2014
Effects of recommendations to follow the Dietary Approaches to Stop Hypertension (DASH) diet v. usual dietary advice on childhood metabolic syndrome: a randomised cross-over clinical trial.
    The British journal of nutrition, 2013, Volume: 110, Issue:12

    The effects of the Dietary Approaches to Stop Hypertension (DASH) eating plan on childhood metabolic syndrome (MetS) and insulin resistance remain to be determined. The present study aimed to assess the effects of recommendations to follow the DASH diet v. usual dietary advice (UDA) on the MetS and its features in adolescents. In this randomised cross-over clinical trial, sixty post-pubescent adolescent girls with the MetS were randomly assigned to receive either the recommendations to follow the DASH diet or UDA for 6 weeks. After a 4-week washout period, the participants were crossed over to the alternate arm. The DASH group was recommended to consume a diet rich in fruits, vegetables and low-fat dairy products and low in saturated fats, total fats and cholesterol. UDA consisted of general oral advice and written information about healthy food choices based on healthy MyPlate. Compliance was assessed through the quantification of plasma vitamin C levels. In both the groups, fasting venous blood samples were obtained at baseline and at the end of each phase of the intervention. The mean age and weight of the participants were 14.2 (SD 1.7) years and 69 (SD 14.5) kg, respectively. Their mean BMI and waist circumference were 27.3 kg/m2 and 85.6 cm, respectively. Serum vitamin C levels tended to be higher in the DASH phase than in the UDA phase (860 (SE 104) v. 663 (SE 76) ng/l, respectively, P= 0.06). Changes in weight, waist circumference and BMI were not significantly different between the two intervention phases. Although changes in systolic blood pressure were not statistically significant between the two groups (P= 0.13), recommendations to follow the DASH diet prevented the increase in diastolic blood pressure compared with UDA (P= 0.01). We found a significant within-group decrease in serum insulin levels (101.4 (SE 6.2) v. 90.0 (SE 5.5) pmol/l, respectively, P= 0.04) and a non-significant reduction in the homeostasis model assessment for insulin resistance score (P= 0.12) in the DASH group. Compared with the UDA group, the DASH group experienced a significant reduction in the prevalence of the MetS and high blood pressure. Recommendations to follow the DASH eating pattern for 6 weeks among adolescent girls with the MetS led to reduced prevalence of high blood pressure and the MetS and improved diet quality compared with UDA. This type of healthy diet can be considered as a treatment modality for the MetS and its components in children.

    Topics: Adolescent; Ascorbic Acid; Blood Pressure; Body Mass Index; Child; Cross-Over Studies; Female; Humans; Hypertension; Insulin; Insulin Resistance; Metabolic Syndrome; Patient Compliance; Prevalence; Waist Circumference

2013
Microvascular function in younger adults with obesity and metabolic syndrome: role of oxidative stress.
    American journal of physiology. Heart and circulatory physiology, 2013, Oct-15, Volume: 305, Issue:8

    Older adults with cardiovascular disease exhibit microvascular dysfunction and increased levels of reactive oxygen species (ROS). We hypothesized that microvascular impairments begin early in the disease process and can be improved by scavenging ROS. Forearm blood flow (Doppler ultrasound) was measured in 45 young (32 ± 2 yr old) adults (n = 15/group) classified as lean, obese, and metabolic syndrome (MetSyn). Vasodilation in response to endothelial (ACh) and vascular smooth muscle [nitroprusside (NTP) and epoprostenol (Epo)] agonists was tested before and after intra-arterial infusion of ascorbic acid to scavenge ROS. Vasodilation was assessed as a rise in relative vascular conductance (ml·min(-1)·dl(-1)·100 mmHg(-1)). ACh and NTP responses were preserved (P = 0.825 and P = 0.924, respectively), whereas Epo responses were lower in obese and MetSyn adults (P < 0.05) than in lean controls. Scavenging of ROS via infusion of ascorbic acid resulted in an increase in ACh-mediated (P < 0.001) and NTP-mediated (P < 0.001) relative vascular conductance across all groups, suggesting that oxidative stress influences vascular responsiveness in adults with and without overt cardiovascular disease risk. Ascorbic acid had no effect on Epo-mediated vasodilation (P = 0.267). These results suggest that obese and MetSyn adults exhibit preserved endothelium-dependent vasodilation with reduced dependence on prostacyclin and are consistent with an upregulation of compensatory vascular control mechanisms.

    Topics: Acetylcholine; Adult; Antioxidants; Ascorbic Acid; Case-Control Studies; Endothelium, Vascular; Epoprostenol; Humans; Infusions, Intra-Arterial; Metabolic Syndrome; Microvessels; Muscle, Skeletal; Muscle, Smooth, Vascular; Nitroprusside; Obesity; Oxidative Stress; Regional Blood Flow; Ultrasonography, Doppler; Vasodilation; Vasodilator Agents

2013
Effects of long-term antioxidant supplementation and association of serum antioxidant concentrations with risk of metabolic syndrome in adults.
    The American journal of clinical nutrition, 2009, Volume: 90, Issue:2

    Limited observational evidence suggests lower antioxidant concentrations in individuals with the metabolic syndrome (MetS); few randomized controlled trials have addressed the effect of multiple antioxidants on the risk of MetS.. The objective was to examine the effect of antioxidant supplementation for 7.5 y on the incidence of MetS and the epidemiologic association between baseline serum antioxidant concentrations and the prospective risk of MetS.. Adults (n = 5220) participating in the SUpplementation en VItamines et Minéraux AntioXydants (SU.VI.MAX) primary prevention trial were randomly assigned to receive a supplement containing a combination of antioxidants (vitamins C and E, beta-carotene, zinc, and selenium) at nutritional doses or a placebo. Subjects were free of MetS at baseline and were followed for 7.5 y.. Antioxidant supplementation for 7.5 y did not affect the risk of MetS. Baseline serum antioxidant concentrations of beta-carotene and vitamin C, however, were negatively associated with the risk of MetS; the adjusted odds ratios (and 95% CIs) for the highest compared with the lowest tertile were 0.34 (0.21, 0.53; P for trend = 0.0002) and 0.53 (0.35, 0.80; P for trend = 0.01), respectively. Baseline serum zinc concentrations were positively associated with the risk of developing MetS; the adjusted odds ratio (and 95% CI) for the highest compared with the lowest tertile was 1.81 (1.20, 2.72; P for trend = 0.01).. The experimental finding of no beneficial effects of antioxidant supplementation in a generally well-nourished population is consistent with recent reports of a lack of efficacy of antioxidant supplements. However, the relations observed between the risk of MetS and baseline serum antioxidant concentrations, which probably reflect associations with overall dietary patterns, do support the current recommendations to consume antioxidant-rich foods. This trial was registered at clinicaltrials.gov as NCT00272428.

    Topics: Antioxidants; Ascorbic Acid; beta Carotene; Dietary Supplements; Double-Blind Method; Female; Follow-Up Studies; France; Humans; Incidence; Male; Metabolic Syndrome; Middle Aged; Minerals; Odds Ratio; Risk Factors; Selenium; Vitamin E; Vitamins; Zinc

2009
Oxidative stress-mediated arterial dysfunction in patients with metabolic syndrome: Effect of ascorbic acid.
    Free radical biology & medicine, 2007, Sep-01, Volume: 43, Issue:5

    Arterial dysfunction is a hallmark of early atherosclerosis; however, its behavior in patients with metabolic syndrome (MS) is still unclear. We investigated the role of oxidative stress on ischemia-induced flow-mediated dilatation (FMD) in patients with MS. FMD and oxidative stress, as assessed by serum levels of 8-hydroxy-2-deoxy-2-deoxyguanosine (8-OHdG), were studied in 18 MS and 30 control subjects. Thereafter, in the 18 MS patients, FMD was assessed after iv infusion of 1 g vitamin C or placebo in a randomized, double-blind, crossover design; serial blood samples were taken in peripheral circulation before and after FMD to analyze 8-OHdG. Compared to controls, MS patients had higher 8-OHdG (p<0.001) and lower FMD (p<0.001); 8-OHdG and FMD were inversely correlated (R=-0.74; p<0.01). In MS patients, placebo administration did not change FMD, whereas vitamin C significantly enhanced it (p<0.001). After placebo, ischemia-induced FMD was associated with a significant increase in 8-OHdG (p<0.001), an effect that was counteracted by vitamin C. Vitamin C infusion was associated with an inverse correlation between the changes in FMD and oxidative stress (R=-0.67; p<0.01). The present study shows that arterial dilatation is impaired and that enhanced oxidative stress may play a key role in patients with MS.

    Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Arteries; Ascorbic Acid; Cross-Sectional Studies; Deoxyguanine Nucleotides; Humans; Male; Metabolic Syndrome; Middle Aged; Oxidative Stress

2007
Insulin causes endothelial dysfunction in humans: sites and mechanisms.
    Circulation, 2002, Feb-05, Volume: 105, Issue:5

    Insulin resistance is often accompanied by hyperinsulinemia and may predispose to atherosclerosis. Endothelium plays a central role in atherogenesis. The in vivo effects of hyperinsulinemia on endothelial function of large conduit arteries are unknown.. Twenty-five healthy subjects were enrolled for study. In study A (n=9), subjects underwent both a time-control saline study and a euglycemic low-dose insulin (insulin approximately 110 pmol/L) clamp for 6 hours. Study B (n=5) was identical to study A except that the euglycemic clamp was performed at high physiological insulin concentrations (approximately 440 pmol/L). In study C (n=7), subjects underwent two 4-hour euglycemic insulin (approximately 110 pmol/L) clamps with and without the concomitant infusion of an antioxidant (vitamin C). In study D (n=4), two saline time-control studies were performed with and without the concomitant infusion of vitamin C. In all studies, both at baseline and throughout the experimental period, endothelium-dependent (flow-mediated) and endothelium-independent (nitroglycerin-induced) vasodilation was assessed in femoral and brachial arteries by echo Doppler. Both low (study A) and high physiological (study B) hyperinsulinemia abolished endothelium-dependent vasodilation, whereas endothelium-independent vasodilation was unaffected. Vitamin C fully restored insulin-impaired endothelial function without affecting endothelium-independent vasodilation (study C). Vitamin C had no effects on endothelium-dependent or endothelium-independent vasodilation during saline control studies (study D).. Modest hyperinsulinemia, mimicking fasting hyperinsulinemia of insulin-resistant states, abrogates endothelium-dependent vasodilation in large conduit arteries, probably by increasing oxidant stress. These data may provide a novel pathophysiological basis to the epidemiological link between hyperinsulinemia/insulin-resistance and atherosclerosis in humans.

    Topics: Adult; Antioxidants; Ascorbic Acid; Brachial Artery; Dose-Response Relationship, Drug; Endothelium, Vascular; Female; Femoral Artery; Glucose Clamp Technique; Humans; Hyperinsulinism; Insulin; Male; Metabolic Syndrome; Regional Blood Flow; Sodium Chloride; Ultrasonography, Doppler; Vascular Patency; Vasodilation; Vasodilator Agents

2002

Other Studies

25 other study(ies) available for ascorbic-acid and Metabolic-Syndrome

ArticleYear
Association of polygenic risk scores for insulin resistance risk and their interaction with a plant-based diet, especially fruits, vitamin C, and flavonoid intake, in Asian adults.
    Nutrition (Burbank, Los Angeles County, Calif.), 2023, Volume: 111

    Insulin resistance is a common risk factor for metabolic syndrome (MetS), leading to type 2 diabetes mellitus and cardiovascular diseases. This study tested the hypothesis that the polygenic variants associated with the risk of insulin resistance (IR) interact with the lifestyles and nutrient intake of participants aged >40 in a large city hospital-based cohort (n = 58 701).. Polygenic risk score (PRS)-lifestyle interactions were evaluated. The participants were categorized into IR (case) and no IR (control) groups using a cutoff of a homeostasis model assessment of IR of 2.32, as estimated with a prediction model generated from the Ansan-Ansung cohort. Single-nucleotide polymorphism (SNP) with an SNP-SNP interaction influencing IR risk were identified using a genome-wide association study and generalized multifactor dimensionality reduction analysis after adjusting for IR-related variables. The selected genetic variants were confirmed in the Ansan-Ansung cohort.. IR was associated mainly with body mass index by 14.24, fat mass by 4.57, and MetS by 8.10 times. Serum high-sensitive C-reactive protein, aspartate aminotransferase, and alanine aminotransferase concentrations were positively associated with IR risk. Plant-based diet (PBD), vitamin C (V-C), and flavonoid intakes were inversely associated with IR risk. The optimal model with SNP-SNP interaction included seven SNPs (CDKAL1_rs7754840, HNF4A_rs4812829, GCKR_rs780093, SLC30A8_rs11558471, KCNQ1_rs2237895, ANK2_rs12503758, and PTPRD_rs10977434) from generalized multifactor dimensionality reduction. After adjusting for the covariates, a high PRS of the seven-SNP model was positively associated with an IR risk of 1.78 times. The seven-SNP model interacted with the energy and PBD intake (especially, high in fruit, V-C and flavonoid). to influence IR risk. In the participants with low-energy, PBD, fruit, flavonoid, and V-C intakes, the percentage of high IR was higher in the high- than in the low-PRS group.. Adults having a high PRS for IR may benefit from a PBD containing high amounts of fruits, V-C, and flavonoids, which were found inversely related to IR risk. The results can be applied to personalized nutrition.

    Topics: Adult; Ascorbic Acid; Diabetes Mellitus, Type 2; Diet, Vegetarian; Flavonoids; Fruit; Genome-Wide Association Study; Humans; Insulin Resistance; Metabolic Syndrome; Polymorphism, Single Nucleotide; Risk Factors

2023
Maternal consumption of l-malic acid enriched diets improves antioxidant capacity and glucose metabolism in offspring by regulating the gut microbiota.
    Redox biology, 2023, Volume: 67

    Maternal diets during pregnancy and lactation are key determinants that regulate the development of metabolic syndrome (MetS) in offspring. l-malic acid (MA) was previously reported to improve antioxidant capacity and aerobic metabolism. However, the effects of maternal MA consumption on the metabolic features of offspring remain largely unexplored. Herein, through pig models consuming MA-enriched diets during late pregnancy and lactation, we found that maternal MA consumption potentiated the anti-inflammatory and antioxidant capacity of sows, thereby improving their reproductive performance and the growth performance of piglets. Maternal MA consumption also induced a transition of slow-twitch to fast-twitch fibers in the early life of offspring. Along with muscle growth and fiber-type transition, insulin sensitivity and glucose metabolism, including aerobic metabolism and glycolysis, were improved in the skeletal muscle of offspring. An untargeted metabolomic analysis further revealed the contribution of modified amino acid metabolism to the improved aerobic metabolism. Mechanistically, maternal MA consumption remodeled colonic microbiota of their offspring. Briefly, the abundance of Colidextribacter, Romboutsia, and Family_XIII_AD3011_group increased, which were positively associated with the antioxidant capacity and glucose metabolism of skeletal muscles. A decreased abundance of Prevotella, Blautia, Prevotellaceae_NK3B31_group, and Collinsella was also detected, which were involved in less insulin sensitivity. Notably, milk metabolites, such as ascorbic acid (AA) and granisetron (GS), were found as key effectors regulating the gut microbiota composition of piglets. The properties of AA and GS in alleviating insulin resistance, inflammation, and oxidative stress were further verified through mice treated with high-fat diets. Overall, this study revealed that maternal MA consumption could modulate the inflammatory response, antioxidant capacity, and glucose metabolism by regulating the gut microbiota of offspring through the vertical transmission of milk metabolites. These findings suggest the potential of MA in the prevention and treatment of MetS in early life.

    Topics: Animals; Antioxidants; Ascorbic Acid; Diet, High-Fat; Female; Gastrointestinal Microbiome; Glucose; Insulin Resistance; Metabolic Syndrome; Mice; Pregnancy; Swine

2023
Nutrient patterns and their relation to obesity and metabolic syndrome in Iranian overweight and obese adult women.
    Eating and weight disorders : EWD, 2022, Volume: 27, Issue:4

    Nutrient patterns have been associated with an increased risk for chronic disease. Evidence to confirm a direct relationship between nutrient patterns and obesity and metabolic syndrome (MetS) throughout population-based differences including cultural contexts add complexity is not well established yet. The aim of this study is to investigate the association between nutrient patterns and MetS among overweight and obese Iranian women.. Three hundred and sixty obese and overweight women (25 < BMI < 40) were included in this cross-sectional analysis. Dietary intake of 19 nutrients was evaluated by a semi-quantitative standard food frequency questionnaire (FFQ). MetS was determined by abdominal obesity > 88 (cm) in females, Triglycerides ≥ 150 (mg/dL), dyslipidemia (HDL < 50 mg/dL), systolic blood pressure > 130/85 (millimeters), and glucose > 100 (mg/dL). Body composition was assessed by a multi-frequency bioelectrical impedance analyzer, InBody 770 scanner. Principle components analysis was applied and four nutrient patterns were identified as following: Pattern 1 (thiamin, iron, carbohydrate, zinc, niacin, protein, magnesium, phosphorus, riboflavin), represented the carbo-vitamin group. Lipid group was showed in pattern 2 (PUFAs, MUFA, vitamin E, trans fatty acids, and Pattern 3 (beta-carotene, vitamin K, vitamin A, vitamin C) represented the anti-oxidant group, finally Pattern 4 was the indicator of the milk group (vitamin D, calcium).. A significant positive association was observed between the anti-oxidant group and obesity (OR 1.40; 95% CI 1.09-1.8; P = 0.01). No relationship between other nutrient pattern and MetS was observed.. The nutrient patterns that are highly loading of beta-carotene, vitamin K, vitamin A, and vitamin C in nutrient patterns may be associated to higher risk of obesity in overweight and obese Iranian women.. Level V, cross-sectional descriptive study.

    Topics: Adult; Antioxidants; Ascorbic Acid; beta Carotene; Cross-Sectional Studies; Female; Humans; Iran; Metabolic Syndrome; Nutrients; Obesity; Overweight; Vitamin A; Vitamin K

2022
Dietary calamondin supplementation slows the progression of non-alcoholic fatty liver disease in C57BL/6 mice fed a high-fat diet.
    International journal of food sciences and nutrition, 2021, Volume: 72, Issue:3

    Obesity is associated with an increased risk of metabolic abnormalities. The citrus fruit calamondin contains nobiletin and hesperidin, which are involved in lipid metabolism, and vitamin C, which is an antioxidant. We investigated the metabolic profiles of C57BL/6 mice fed a normal diet, high-fat diet (HFD), HFD + 1% (w/w) calamondin puree (HFD + CL1), or HFD + 5% (w/w) calamondin puree (HFD + CL5). Glucose tolerance was significantly higher in HFD + CL than in HFD-fed mice. Histological analysis revealed less lipid accumulation in the livers of HFD + CL-fed mice than in those of HFD-fed control mice. Hepatocyte ballooning and large lipid droplets - key non-alcoholic fatty liver disease characteristics - were observed in HFD-fed mice after 4 weeks; however, they were nearly absent in HFD + CL-fed mice. The serum expression level of inflammation-associated Ccl2 was lower in HFD + CL-fed mice than in HFD-fed mice. Thus, calamondin may ameliorate HFD-induced metabolic disturbances, including the progression of non-alcoholic fatty liver disease.

    Topics: Adipose Tissue; Alanine Transaminase; Animals; Antioxidants; Ascorbic Acid; Body Weight; Chemokine CCL2; Citrus; Diet; Diet, High-Fat; Dietary Supplements; Gene Expression; Inflammation; Insulin; Lipid Metabolism; Liver; Male; Metabolic Syndrome; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Obesity

2021
[An assessment of the antioxidant vitamins concentration in people with metabolic syndrome working in agriculture].
    Medycyna pracy, 2021, Apr-09, Volume: 72, Issue:2

    Vitamins A, C and E are important parts of the antioxidant barrier. Polish data on antioxidant vitamins deficiency in the population are rare, especially among physically active people with metabolic disorders. The aim of this study was to evaluate the serum concentrations of vitamins A, C and E in people with metabolic syndrome (MS) working in agriculture, the prevalence of their deficiency in these workers, and the correlation between antioxidant vitamins concentration and traditional biomarkers of cardiovascular diseases.. The study included 332 residents of the Łódź Voivodeship working in agriculture: 231 people with MS and 101 healthy ones. The serum concentrations of vitamins A, C and E were assessed using the chemiluminescent immunoassay technology. The antioxidant vitamins intake was assessed by means of a 24-h recall questionnaire using Diet 5.0 software.. The mean serum concentrations of vitamins A, C and E were significantly lower in the MS workers than in the healthy ones No correlation was found between the antioxidant vitamins concentration and the dietary intake but there was a correlation between the antioxidant vitamins concentration and high-density lipoprotein cholesterol (HDL-C). A correlation was found between the serum concentrations of vitamins A and C, and vitamins A and E, in the MS workers.. The serum concentrations of antioxidant vitamins in the MS workers were significantly lower than in the healthy controls, despite the similar physical activity level. The dietary intake had no impact on the serum concentrations of these vitamins. The HDL-C concentration in the MS workers correlated with the concentrations of all antioxidant vitamins. Med Pr. 2021;72(2):123-9.. Witaminy A, C i E stanowią ważną barierę antyoksydacyjną. Danych dotyczących stanu odżywienia populacji polskiej witaminami antyoksydacyjnymi jest niewiele, a szczególnie mało dotyczy osób aktywnych fizycznie z zaburzeniami metabolicznymi. Celem badania była ocena stężenia witamin A, C i E w surowicy krwi i częstości ich niedoborów u osób z zespołem metabolicznym (ZM) pracujących w rolnictwie oraz zależności między stężeniem witamin antyoksydacyjnych w surowicy a tradycyjnymi biomarkerami chorób sercowo-naczyniowych.. W badaniu wzięło udział 332 mieszkańców województwa łódzkiego pracujących w rolnictwie: 231 osób z ZM i 101 osób zdrowych. Stężenie witamin A, C i E w surowicy krwi badano za pomocą wysokosprawnej chromatografii cieczowej, a spożycie witamin z dietą oceniano za pomocą programu Dieta 5.0 na podstawie 24-godzinnych wywiadów żywieniowych.. Średnie stężenia witamin A, C i E w surowicy krwi osób z ZM były istotnie mniejsze niż w grupie bez ZM. Stężenie nie korelowało ze spożyciem witamin z dietą, ale korelowało ze stężeniem cholesterolu HDL. Stwierdzono korelację między stężeniem w surowicy witamin A i C oraz A i E u pracowników z ZM.. Stężenie witamin antyoksydacyjnych w surowicy pracowników z ZM było istotnie mniejsze niż w grupie osób zdrowych, mimo podobnego poziomu aktywności fizycznej. Wysokie spożycie witamin z dietą nie różnicowało ich stężenia w surowicy osób z ZM zatrudnionych w rolnictwie. Stężenie cholesterolu HDL u osób z ZM korelowało ze stężeniem wszystkich witamin antyoksydacyjnych. Med. Pr. 2021;72(2):123–129.

    Topics: Adult; Aged; Agriculture; Ascorbic Acid; Cholesterol, HDL; Eating; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Poland; Vitamin A; Vitamin E

2021
A Healthy Diet Rich in Calcium and Vitamin C Is Inversely Associated with Metabolic Syndrome Risk in Korean Adults from the KNHANES 2013-2017.
    Nutrients, 2021, Apr-16, Volume: 13, Issue:4

    The association between metabolic syndrome and eating patterns remains unclear. We hypothesized that Korean Healthy Eating Index (KHEI) scores were related to metabolic syndrome (MetS) risk in adults in a gender-dependent manner. We aimed to examine the hypothesis using the Korea National Health and Nutrition Examination Survey-VI (2013-2017) data with a complex sample survey design. Adjusted means and 95% confidence intervals of KHEI scores and nutrient intake estimated by the 24-h recall were calculated according to MetS status after adjusting for age, residence area, region, education, obesity, income, drinking status, smoking status, marriage, and exercise. Adjusted odds ratios for MetS were measured according to KHEI quartiles using logistic regression analysis while controlling for covariates. MetS incidence was significantly higher in females than in males. Those who were older, less educated, earning less income, more obese, living in rural areas, drinking severely, non-exercising, and married had higher MetS incidence than those with the opposite state. Total KHEI scores of all components KHEI scores were lower for those with MetS (MetS group) than those without MetS (Non-MetS group) in both genders. For KHEI components, having breakfast and milk and fat intake had lower scores for the MetS group than for the Non-MetS group in women, whereas fruits and milk and milk product intake had lower scores for the MetS group in men. Nutrient intake influenced the MetS risk in females more than in males. Fat, calcium, and vitamin C intakes from 24-h recall were lower in the MetS group than in the Non-MetS group in women. KHEI scores had an inverse association with MetS risk by 0.98-fold in both genders after adjusting for covariates. In conclusion, a healthy diet that includes adequate calcium and vitamin C is associated with a lower the risk of MetS in both men and women.

    Topics: Adult; Ascorbic Acid; Calcium, Dietary; Cardiometabolic Risk Factors; Diet, Healthy; Eating; Feeding Behavior; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Nutrition Surveys; Odds Ratio; Republic of Korea; Young Adult

2021
Glycomacropeptide Prevents Iron/Ascorbate-Induced Oxidative Stress, Inflammation and Insulin Sensitivity with an Impact on Lipoprotein Production in Intestinal Caco-2/15 Cells.
    Nutrients, 2020, Apr-22, Volume: 12, Issue:4

    Metabolic Syndrome (MetS), a major worldwide concern for the public health system, refers to a cluster of key metabolic components, and represents a risk factor for diabetes and cardiovascular diseases. As oxidative stress (OxS) and inflammation are the major triggers of insulin sensitivity (IS), a cardinal MetS feature, the principal aim of the present work is to determine whether glycomacropeptide (GMP), a milk-derived bioactive peptide, exerts beneficial effects on their expression.. Fully differentiated intestinal Caco-2/15 cells are used to evaluate the preventive action of 2 mg/mL GMP against OxS and inflammation induced by the mixture iron-ascorbate (Fe/Asc) (200 μM:2 mM). The potency of GMP of decreasing the production of lipoproteins, including chylomicrons (CM), very-low-density lipoproteins (VLDL) and low-density lipoproteins (LDL) is also assessed.. The administration of GMP significantly reduces malondialdehyde, a biomarker of lipid peroxidation, and raises superoxide dismutase 2 and glutathione peroxidase via the induction of the nuclear factor erythroid 2-related factor 2, a transcription factor, which orchestrates cellular antioxidant defenses. Similarly, GMP markedly lowers the inflammatory agents tumor necrosis factor-α and cyclooxygenase-2 via abrogation of the nuclear transcription factor-kB. Moreover, GMP-treated cells show a down-regulation of Fe/Asc-induced mitogen activated protein kinase pathway, suggesting greater IS. Finally, GMP decreases the production of CM, VLDL, and LDL.. Our results highlight the effectiveness of GMP in attenuating OxS, inflammation and lipoprotein biogenesis, as well as improving IS, the key components of MetS. Further investigation is needed to elucidate the mechanisms mediating the preventive action of GMP.

    Topics: Ascorbic Acid; Caco-2 Cells; Caseins; Glutathione Peroxidase; Humans; Inflammation; Inflammation Mediators; Insulin Resistance; Intestinal Mucosa; Iron; Lipoproteins; Malondialdehyde; Metabolic Syndrome; Mitogen-Activated Protein Kinases; Oxidative Stress; Peptide Fragments; Superoxide Dismutase

2020
Association of antioxidant status and inflammatory markers with metabolic syndrome in Thais.
    Journal of health, population, and nutrition, 2019, 01-03, Volume: 38, Issue:1

    An oxidant/antioxidant disequilibrium has been suggested as having a role in the pathogenesis of some diseases. Metabolic syndrome (MS) is significantly associated with cardiovascular disease and type 2 diabetes. The pathogenesis of MS is complex and not well understood. The purposes of the present study were to compare enzymatic and non-enzyme antioxidants, anthropometric, hematological, and biochemical findings between subjects with MS and without MS and to evaluate the relationship between antioxidant status and hematological parameters with the components of MS.. Metabolic syndrome was assessed by using the modified National Cholesterol Education Program, Adult Treatment Panel III criteria. Three hundred Thais, 124 with MS and 176 without MS, were included in the study. Each subject was tested for erythrocyte superoxide dismutase (SOD), glutathione peroxidase, (GPX), catalase (CAT), albumin and vitamin C levels, and hematological findings.. Subjects with MS had lower SOD and CAT levels than those without MS (p < 0.01). Subjects with MS had lower vitamin C and albumin levels than those without MS (p < 0.05). The hematological findings were not significantly different between those with and without MS except the white blood cell (WBC) count which was significantly higher in those with MS. SOD and CAT levels were significantly positively associated with HDL-C levels and negatively associated with components of MS. After adjusting for potential covariates, we found lower SOD and vitamin C levels and higher WBC counts were significantly associated with MS (p < 0.05).. These findings suggest an alteration in antioxidant status and an increase in inflammatory markers are associated with MS and its components among Thais; subjects with MS may be more likely to have oxidative stress problems.

    Topics: Adult; Anthropometry; Antioxidants; Ascorbic Acid; Biomarkers; Catalase; Female; Glutathione Peroxidase; Humans; Inflammation; Logistic Models; Male; Metabolic Syndrome; Middle Aged; Superoxide Dismutase; Thailand

2019
The risk of plasma vitamin A, C, E and D deficiency in patients with metabolic syndrome: A case-control study.
    Advances in clinical and experimental medicine : official organ Wroclaw Medical University, 2017, Volume: 26, Issue:4

    The increasing incidence of metabolic diseases such as obesity or diabetes have made them a major public health problem. Increasing oxidative stress induced by reactive oxygen species, which initiate the oxidative adverse changes in the cell, is mentioned, among other risk factors, to underlie these diseases. Vitamin A, C and E are listed among the non-enzymatic mechanisms counteracting this phenomenon. Vitamin D deficiency is also associated with cardiovascular diseases.. The aim of the study was to assess the risk of vitamin A, C, E and D deficit in the plasma of metabolic syndrome (MS) patients.. The study included 191 patients with MS and 98 subjects without MS. Loglinear analysis was used in the assessment of mutual interactions between the vitamin concentration and the analysis of classification by ROC curves to predict the frequency of vitamin deficiency in MS patients.. A correlation was found between the plasma level of vitamins in the group of MS patients. Vitamin A concentration correlated with that of vitamin C (r = 0.51, p = 0.0000), vitamin D (r = 0.49, p = 0.0000) and E (r = 0.32, p = 0.0001). The plasma level of vitamin D correlated with the level of vitamin E (r = 0.46, p = 0.00000) and vitamin C (r = 0.37, p = 0.0000). Regression analysis showed a correlation between the concentration of the tested vitamins in patients with MS. Interactions were observed between vitamins C and A and between C and D. HDL cholesterol level was lower in patients with vitamin A deficiency compared to patients with its normal level.. The plasma levels of vitamin A, C, E and D were significantly lower in patients with MS than in healthy subjects and they mutually correlated with each other. The normalization of glucose and HDL level may contribute to the regulation of the concentration of vitamin A in patients with MS.

    Topics: Adult; Aged; Ascorbic Acid; Ascorbic Acid Deficiency; Case-Control Studies; Cholesterol, HDL; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Reactive Oxygen Species; Risk; Vitamin A; Vitamin A Deficiency; Vitamin D; Vitamin D Deficiency; Vitamin E; Vitamin E Deficiency

2017
Chemical and functional characterization of seed, pulp and skin powder from chilto (Solanum betaceum), an Argentine native fruit. Phenolic fractions affect key enzymes involved in metabolic syndrome and oxidative stress.
    Food chemistry, 2017, Feb-01, Volume: 216

    The aim of this work was to assess the nutritional and functional components of powder obtained by lyophilization of whole fruits, seeds, pulp and skin from chilto (Solanum betaceum Cav) cultivated in the ecoregion of Yungas, Argentina. The powders have low carbohydrate and sodium content and are a source of vitamin C, carotenoid, phenolics, potassium and fiber. The HPLC-ESI-MS/MS analysis of the fractions enriched in phenolics allowed the identification of 12 caffeic acid derivatives and related phenolics, 10 rosmarinic acid derivatives and 7 flavonoids. The polyphenols enriched extracts before and after simulated gastroduodenal digestion inhibited enzymes associated with metabolic syndrome, including α-glucosidase, amylase and lipase and exhibited antioxidant activity by different mechanisms. None of the analyzed fruit powders showed acute toxicity or genotoxicity. The powders from the three parts of S. betaceum fruit may be a potential functional food and the polyphenol enriched extract of seed and skin may have nutraceutical properties.

    Topics: alpha-Amylases; alpha-Glucosidases; Antioxidants; Argentina; Ascorbic Acid; Carotenoids; Cinnamates; Depsides; Dietary Fiber; Female; Flavonoids; Fruit; Glycoside Hydrolase Inhibitors; Humans; Inhibitory Concentration 50; Lipase; Male; Metabolic Syndrome; Oxidative Stress; Phytochemicals; Plant Preparations; Polyphenols; Potassium, Dietary; Powders; Recommended Dietary Allowances; Rosmarinic Acid; Seeds; Solanum; Tandem Mass Spectrometry

2017
Physical activity, dietary vitamin C, and metabolic syndrome in the Korean adults: the Korea National Health and Nutrition Examination Survey 2008 to 2012.
    Public health, 2016, Volume: 135

    Metabolic syndrome is a global public health problem, and regular physical activity is a well-known critical factor in its management. A recent study suggests that the effect of exercise on metabolic syndrome may be enhanced by sufficient plasma vitamin C concentrations. We therefore examined the combined effect of physical activity and dietary vitamin C on the risk of metabolic syndrome in the general Korean population.. Cross-sectional study.. We analyzed data from 22,671 adults aged 20 years or older from the Korea National Health and Nutrition Examination Survey 2008-2012. Physical activity was computed as the total metabolic equivalent (METs-hr/week) summed from MET scores of walking, moderate activity, and vigorous activity. Vitamin C intake was assessed using a 24-h dietary recall. Participants were classified into four combined groups based on median values of physical activity and vitamin C intake.. After adjustment for potential confounders, the odds ratio (OR) for metabolic syndrome in individuals with both high physical activity and vitamin C intake (vs. both low physical activity and vitamin C intake) was 0.79 (95% confidence interval (CI), 0.71-0.87). The estimated combined effect was more than either high physical activity alone (OR, 0.81 (95% CI, 0.73-0.90)) or high vitamin C intake alone (OR, 0.89 (95% CI, 0.80-0.99)), although each of those was beneficial.. Physical activity and dietary intake of vitamin C are both associated with a lower risk of metabolic syndrome. Our findings suggest further that a combination of physical activity and a diet rich in vitamin C may help in preventing metabolic syndrome.

    Topics: Adult; Ascorbic Acid; Cross-Sectional Studies; Diet; Exercise; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Nutrition Surveys; Republic of Korea; Risk Factors; Young Adult

2016
Effects of total vitamin A, vitamin C, and fruit intake on risk for metabolic syndrome in Korean women and men.
    Nutrition (Burbank, Los Angeles County, Calif.), 2015, Volume: 31, Issue:1

    The question of whether the consumption of antioxidants prevents and alleviates metabolic syndrome (MetS) by reducing insulin resistance remains controversial. The aim of this study was to assess whether the intake of vitamin A (including β-carotene), vitamin C, fruits, or vegetables was negatively associated with MetS in Korean adults aged ≥ 20 y.. We conducted a cross-sectional study of 27,656 adults ≥ 20 y of age who participated in the 2007-2012 Korean National Health and Nutrition Examination Survey. Daily intake of vitamin A and vitamin C was assessed by 24-h recall, and the consumption of fruits and vegetables was determined using a food frequency questionnaire. Odds ratios (ORs) for MetS were calculated for log2-transformed vitamin A and C intake values and for the interaction of sex with vitamin A and C intake, after covariate adjustment.. Interactions were seen between total vitamin A and C intake and sex for MetS. With a twofold increase in total vitamin A and C intake in women, the ORs (95% confidence intervals) for metabolic syndrome were 0.942 (0.901-0.985) and 0.933 (0.883-0.987), indicating decreases of 5.8% and 6.7% in MetS, respectively. There were no equivalent decreases in men. Women in the second and highest tertiles of fruit intake exhibited 17.5% and 21.8% lower incidences of MetS, respectively, compared with women in the lowest tertile.. The intake of total vitamin A and C, as well as moderate and high fruit intake, may have alleviated MetS in women, but not in men, in a representative sample of the general South Korean population.

    Topics: Adult; Antioxidants; Ascorbic Acid; Asian People; Blood Glucose; Blood Pressure; Body Mass Index; Cholesterol, HDL; Cross-Sectional Studies; Fasting; Female; Fruit; Humans; Insulin Resistance; Male; Mental Recall; Metabolic Syndrome; Middle Aged; Nutrition Surveys; Prevalence; Republic of Korea; Risk Factors; Surveys and Questionnaires; Triglycerides; Vegetables; Vitamin A; Waist Circumference; Young Adult

2015
Associations between Dietary Antioxidant Intake and Metabolic Syndrome.
    PloS one, 2015, Volume: 10, Issue:6

    The objective of this study was to evaluate the association between dietary antioxidant intake (carotenoid, vitamin C, E and selenium) intake and metabolic syndrome (MS).. This cross-sectional study included 2069 subjects undergoing a regular health checkup. Biochemical test results and data on dietary intakes were collected for analysis. Adjustment for energy intake and multi-variable logistic regression were performed to determine adjusted odds ratios (ORs) and corresponding 95% confidence intervals (95%CI) for the relationship between dietary antioxidants intake and MS. The lowest quartile of antioxidant intake was regarded as the reference category.. Dietary vitamin C intake (P values for trend were 0.02 in energy adjusted analysis and 0.08 in multivariable adjusted analysis) had a negative association with MS, as did selenium intake in the second quartile (energy adjusted OR: 0.60, 95%CI: 0.43 to 0.85; multivariable adjusted OR: 0.60, 95%CI: 0.43 to 0.86). However, there was no significant relationship between dietary carotenoid and vitamin E intake and MS.. Subjects with low intake of vitamin C might be predisposed to development of MS, while dietary selenium intake had a moderate negative association with MS. Dietary carotenoid and vitamin E intake was not associated with MS.

    Topics: Antioxidants; Ascorbic Acid; Carotenoids; Cross-Sectional Studies; Diet; Energy Intake; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Selenium; Vitamin E

2015
Contribution of Inflammation, Oxidative Stress, and Antioxidants to the Relationship between Sleep Duration and Cardiometabolic Health.
    Sleep, 2015, Dec-01, Volume: 38, Issue:12

    To explore the interrelationship and mediating effect of factors that are beneficial (i.e., antioxidants) and harmful (i.e., inflammation and oxidative stress) to the relationship between sleep and cardiometabolic health.. Cross-sectional data from the 2005-2006 National Health and Nutrition Examination Survey.. Nationally representative population sample from the US.. Age ≥ 20 y with sleep data; final analytical sample of n = 2,079.. N/A.. Metabolic syndrome was classified according to the Joint Interim Statement, and sleep duration was categorized as very short, short, adequate, and long sleepers (≤ 4, 5-6, 7-8, and ≥ 9 h per night, respectively). The indirect mediation effect was quantified as large (≥ 0.25), moderate (≥ 0.09), modest (≥ 0.01), and weak (< 0.01). In general, inflammation was above the current clinical reference range across all sleep duration categories, whereas oxidative stress was elevated among short and very short sleepers. Select sleep duration- cardiometabolic health relationships were mediated by C-reactive protein (CRP), γ-glutamyl transferase (GGT), carotenoids, uric acid, and vitamins C and D, and were moderated by sex. Specifically, moderate-to-large indirect mediation by GGT, carotenoids, uric acid, and vitamin D were found for sleep duration-waist circumference and -systolic blood pressure relationships, whereas vitamin C was a moderate mediator of the sleep duration-diastolic blood pressure relationship.. Several factors related to inflammation, oxidative stress, and antioxidant status were found to lie on the casual pathway of the sleep duration-cardiometabolic health relationship. Further longitudinal studies are needed to confirm our results.

    Topics: Adult; Aged; Antioxidants; Ascorbic Acid; Blood Pressure; C-Reactive Protein; Cardiovascular Physiological Phenomena; Carotenoids; Cross-Sectional Studies; Female; Health Surveys; Humans; Inflammation; Longitudinal Studies; Male; Metabolic Syndrome; Middle Aged; Nutrition Surveys; Oxidative Stress; Sex Characteristics; Sleep; Time Factors; Transglutaminases; United States; Uric Acid; Vitamin D; Waist Circumference

2015
Quantitative combination of natural anti-oxidants prevents metabolic syndrome by reducing oxidative stress.
    Redox biology, 2015, Volume: 6

    Insulin resistance and abdominal obesity are present in the majority of people with the metabolic syndrome. Antioxidant therapy might be a useful strategy for type 2 diabetes and other insulin-resistant states. The combination of vitamin C (Vc) and vitamin E has synthetic scavenging effect on free radicals and inhibition effect on lipid peroxidation. However, there are few studies about how to define the best combination of more than three anti-oxidants as it is difficult or impossible to test the anti-oxidant effect of the combination of every concentration of each ingredient experimentally. Here we present a math model, which is based on the classical Hill equation to determine the best combination, called Fixed Dose Combination (FDC), of several natural anti-oxidants, including Vc, green tea polyphenols (GTP) and grape seed extract proanthocyanidin (GSEP). Then we investigated the effects of FDC on oxidative stress, blood glucose and serum lipid levels in cultured 3T3-L1 adipocytes, high fat diet (HFD)-fed rats which serve as obesity model, and KK-ay mice as diabetic model. The level of serum malondialdehyde (MDA) in the treated rats was studied and Hematoxylin-Eosin (HE) staining or Oil red slices of liver and adipose tissue in the rats were examined as well. FDC shows excellent antioxidant and anti-glycation activity by attenuating lipid peroxidation. FDC determined in this investigation can become a potential solution to reduce obesity, to improve insulin sensitivity and be beneficial for the treatment of fat and diabetic patients. It is the first time to use the math model to determine the best ratio of three anti-oxidants, which can save much more time and chemical materials than traditional experimental method. This quantitative method represents a potentially new and useful strategy to screen all possible combinations of many natural anti-oxidants, therefore may help develop novel therapeutics with the potential to ameliorate the worldwide metabolic abnormalities.

    Topics: 3T3-L1 Cells; Adipocytes; Animals; Ascorbic Acid; Blood Glucose; Catechin; Cell Differentiation; Diet, High-Fat; Dietary Supplements; Factor Analysis, Statistical; Free Radical Scavengers; Grape Seed Extract; Hydroxyl Radical; Lipid Peroxidation; Male; Malondialdehyde; Metabolic Syndrome; Mice; Obesity; Oxidative Stress; Proanthocyanidins; Rats; Rats, Sprague-Dawley

2015
Serum and dietary antioxidant status is associated with lower prevalence of the metabolic syndrome in a study in Shanghai, China.
    Asia Pacific journal of clinical nutrition, 2013, Volume: 22, Issue:1

    The aim of our study was to examine the association between the metabolic syndrome (MS) and serum antioxidant status.. A cross-sectional study was conducted with 221 cases and 329 controls aged 18 to 65 years. Weight, height, body mass index, waist circumference, blood pressure, fasting blood glucose and lipids, as well as serum superoxide dismutase, glutathione peroxidase, malondialdehide, vitamins A, E, β-carotene and lycopene were examined. Intakes of antioxidants were also estimated.. Mean serum superoxide dismutase activity, β-carotene concentrations were significantly lower, malondialdehide was higher (p<0.05) in persons with the MS (after adjusting for age, sex) than those without. Superoxide dismutase, glutathione peroxidase, and β- carotene also decreased significantly (p<0.05) with increased number of components of the MS. Low levels of serum superoxide dismutase activity and β-carotene concentration appeared to be associated with the MS status. Moreover, dietary energy, carbohydrate, vitamin C, zinc and copper intake in the MS patients were lower, but fat intake were higher. Vitamins E, C and manganese intake decreased with the elevated number of the MS components. For zinc and manganese, a lower risk was observed for other quartile of intake compared with the first one. Inverse links between dietary fat, energy intake and serum antioxidant status were found in MS patients, meanwhile dietary vitamin C was positively related with serum antioxidant level.. Serum antioxidant status was associated with a lower prevalence of the MS, and with lower dietary fat, energy intake and higher vitamin C intake.

    Topics: Adolescent; Adult; Aged; Antioxidants; Ascorbic Acid; beta Carotene; Blood Glucose; Blood Pressure; Body Mass Index; Carotenoids; Case-Control Studies; China; Cross-Sectional Studies; Dietary Carbohydrates; Energy Intake; Female; Glutathione Peroxidase; Humans; Linear Models; Logistic Models; Lycopene; Male; Malondialdehyde; Metabolic Syndrome; Middle Aged; Multivariate Analysis; Nutrition Assessment; Nutritional Status; Oxidative Stress; Prevalence; Superoxide Dismutase; Vitamin A; Vitamin E; Waist Circumference; Young Adult; Zinc

2013
Protective effects of azelaic acid against high-fat diet-induced oxidative stress in liver, kidney and heart of C57BL/6J mice.
    Molecular and cellular biochemistry, 2013, Volume: 377, Issue:1-2

    Excess fat intake induces hyperinsulinaemia, increases nutrient uptake and lipid accumulation, amplifies ROS generation, establishes oxidative stress and morphological changes leading to tissue injury in the liver, kidney and heart of high-fat diet (HFD)-fed mice. The effect of azelaic acid (AzA), a C9 α,ω-dicarboxylic acid, against HFD-induced oxidative stress was investigated by assaying the activities and levels of antioxidants and oxidative stress markers in the liver, kidney and heart of C57BL/6J mice. Mice were segregated into two groups, one fed standard diet (NC) and the other fed high-fat diet (HFD) for 15 weeks. HFD-fed mice were subjected to intragastric administration of AzA (80 mg/kg BW)/RSG (10 mg/kg BW) during 11-15 weeks. Glucose, insulin, triglycerides, hepatic and nephritic markers were analysed in the plasma and the activity of enzymatic, non-enzymatic antioxidants and lipid peroxidation markers were examined in the plasma/erythrocytes, liver, kidney and heart of normal and experimental mice. We inferred significant decrease in enzymatic and non-enzymatic antioxidants along with significant increase in glucose, insulin, hepatic and nephritic markers, triglycerides and lipid peroxidation markers in HFD-fed mice. Administration of AzA could positively restore the levels of plasma glucose, insulin, triglycerides, hepatic and nephritic markers to near normal. AzA increased the levels of enzymatic and nonenzymatic antioxidants with significant reduction in the levels of lipid peroxidation markers. Histopathological examination of liver, kidney and heart substantiated these results. Hence, we put forward that AzA could counteract the potential injurious effects of HFD-induced oxidative stress in C57BL/6J mice.

    Topics: Animals; Antioxidants; Ascorbic Acid; Biomarkers; Blood Glucose; Body Weight; Dicarboxylic Acids; Diet, High-Fat; Eating; Erythrocytes; Glutathione; Glutathione Peroxidase; Glutathione Transferase; Heart; Hypoglycemic Agents; Insulin; Kidney; Liver; Male; Metabolic Syndrome; Mice; Mice, Inbred C57BL; Myocardium; Oxidative Stress; Rosiglitazone; Thiazolidinediones; Thiobarbituric Acid Reactive Substances; Triglycerides; Vitamin E

2013
Attenuation of insulin resistance, metabolic syndrome and hepatic oxidative stress by resveratrol in fructose-fed rats.
    Pharmacological research, 2012, Volume: 66, Issue:3

    Metabolic syndrome and oxidative stress are common complications of type 2 diabetes mellitus. The present study was designed to determine whether resveratrol, a widely used nutritional supplement, can improve insulin sensitivity, metabolic complication as well as hepatic oxidative stress in fructose-fed rats. Male Sprague Dawley rats (180-200 g) were divided into four groups with 8 animals each. Fructose-fed insulin resistant group (Dia) animals were fed 65% fructose (Research diet, USA) for a period of 8 weeks, whereas control group (Con) animals were fed 65% cornstarch (Research Diet, USA). Resveratrol, 10 mg/kg/day (Dia+Resv) or metformin 300 mg/kg/day (Dia+Met) were administered orally to the 65% fructose-fed rats for 8 weeks. At the end of the feeding schedule, Dia group had insulin resistance along with increased blood glucose, triglyceride, uric acid and nitric oxide (NO) levels. Significant (p<0.05) increase in hepatic TBARS and conjugated dienes, and significant (p<0.05) decrease in hepatic SOD and vitamin C was observed in Dia group compared to Con group. Administration of metformin or resveratrol significantly (p<0.05) normalized all the altered metabolic parameters. However, a marked insulin sensitizing action was only observed in the Dia+Resv group. Similarly, while metformin administration failed to normalize the increased TBARS levels and decreased SOD activity, resveratrol showed a more promising effect of all oxidative stress parameters measured in the present study. Attenuation of hepatic oxidative stress in fructose-fed rat liver after resveratrol administration was associated with significant (p<0.05) increase in nuclear level of NRF2 compared with other groups. The present study demonstrates that resveratrol is more effective than metformin in improving insulin sensitivity, and attenuating metabolic syndrome and hepatic oxidative stress in fructose-fed rats.

    Topics: Animals; Ascorbic Acid; Blood Glucose; Body Weight; Catalase; Eating; Fructose; Glucose Tolerance Test; Glutathione; Insulin; Insulin Resistance; Liver; Male; Metabolic Syndrome; Metformin; NF-E2-Related Factor 2; Nitric Oxide; Oxidative Stress; Rats; Rats, Sprague-Dawley; Resveratrol; Stilbenes; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Triglycerides; Uric Acid

2012
100% orange juice consumption is associated with better diet quality, improved nutrient adequacy, decreased risk for obesity, and improved biomarkers of health in adults: National Health and Nutrition Examination Survey, 2003-2006.
    Nutrition journal, 2012, Dec-12, Volume: 11

    Consumption of 100% orange juice (OJ) has been positively associated with nutrient adequacy and diet quality, with no increased risk of overweight/obesity in children; however, no one has examined these factors in adults. The purpose of this study was to examine the association of 100% OJ consumption with nutrient adequacy, diet quality, and risk factors for metabolic syndrome (MetS) in a nationally representative sample of adults.. Data from adults 19+ years of age (n = 8,861) participating in the National Health and Nutrition Examination Survey 2003-2006 were used. The National Cancer Institute method was used to estimate the usual intake (UI) of 100% OJ consumption, selected nutrients, and food groups. Percentages of the population below the Estimated Average Requirement (EAR) or above the Adequate Intake (AI) were determined. Diet quality was measured by the Healthy Eating Index-2005 (HEI-2005). Covariate adjusted logistic regression was used to determine if consumers had a lower odds ratio of being overweight or obese or having risk factors of MetS or MetS.. Usual per capita intake of 100% OJ was 50.3 ml/d. Among consumers (n = 2,310; 23.8%), UI was 210.0 ml/d. Compared to non-consumers, consumers had a higher (p < 0.05) percentage (% ± SE) of the population meeting the EAR for vitamin A (39.7 ± 2.5 vs 54.0 ± 1.2), vitamin C (0.0 ± 0.0 vs 59.0 ± 1.4), folate (5.8 ± 0.7 vs 15.1 ± 0.9), and magnesium (51.6 ± 1.6 vs 63.7 ± 1.2). Consumers were also more likely to be above the AI for potassium (4.1 ± 0.8 vs 1.8 ± 0.2). HEI-2005 was significantly (p < 0.05) higher in consumers (55.0 ± 0.4 vs 49.7 ± 0.3). Consumers also had higher intakes of total fruit, fruit juice, whole fruit, and whole grain. Consumers had a lower (p < 0.05) mean body mass index (27.6 ± 0.2 vs 28.5 ± 0.1), total cholesterol levels (197.6 ± 1.2 vs 200.8 ± 0.75 mg/dL), and low density lipoprotein-cholesterol levels (112.5 ± 1.4 vs 116.7 ± 0.93 mg/dL). Finally, compared to non-consumers of 100% OJ, consumers were 21% less likely to be obese and male consumers were 36% less likely to have MetS.. The results suggest that moderate consumption of 100% OJ should be encouraged to help individuals meet the USDA daily recommendation for fruit intake and as a component of a healthy diet.

    Topics: Adult; Ascorbic Acid; Beverages; Biomarkers; Body Mass Index; Cardiovascular Diseases; Cholesterol; Citrus sinensis; Diet; Edible Grain; Female; Folic Acid; Fruit; Humans; Magnesium; Male; Metabolic Syndrome; Motor Activity; Nutrition Surveys; Nutritional Status; Obesity; Potassium, Dietary; Regression Analysis; Risk Factors; Socioeconomic Factors; Surveys and Questionnaires; Vitamin A

2012
Antioxidant status of subjects with Metabolic Syndrome in Port Harcourt, Nigeria.
    The Nigerian postgraduate medical journal, 2012, Volume: 19, Issue:4

    Increased free radical production and thus oxidative stress have been implicated in the pathogenesis of metabolic syndrome. As a result there is depletion of defences against free radical damage which comprise antioxidant enzymes and vitamins like vitamins C and E, resulting in low plasma levels. This study was designed to determine if the plasma total antioxidant status and vitamins C and E levels are lower in metabolic syndrome subjects living in Port Harcourt, Nigeria compared to healthy controls.. One hundred subjects between 21 and 73 years of age who satisfied the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III criteria for metabolic syndrome were recruited into the study. One hundred controls were age- and sex-matched. After determining their blood pressure (mmHg) and waist circumference (cm), the concentrations of plasma glucose (mmol/L), lipid profile (mmol/L), total antioxidant status (TAS, mmol/L), vitamin C (mol/L) and vitamin E (mol/L) were estimated in all participants.. The mean plasma TAS (1.23 ± 0.28mmol/L), vitamin C (27.5 ± 7.4mol/L) and vitamin E (16.9 ± 4.9mol/L) of metabolic syndrome subjects were significantly lower (P=0.0001 for all) than that of controls (1.58 ± 0.28mmol/L, 44.3 ± 7.3mol/ L, 30.8 ± 6.1mol/L respectively).. The TAS, vitamins C and E are reduced in metabolic syndrome subjects compared with that of controls. This may be due to increased oxidative stress resulting from an imbalance between antioxidant defences and increased free radical production.

    Topics: Adult; Aged; Antioxidants; Ascorbic Acid; Blood Glucose; Blood Pressure; Case-Control Studies; Female; Free Radicals; Humans; Lipids; Male; Metabolic Syndrome; Middle Aged; Nigeria; Oxidative Stress; Vitamin E; Waist Circumference

2012
Effects of Zn(II) complex with vitamins C and U, and carnitine on metabolic syndrome model rats.
    Metallomics : integrated biometal science, 2011, Volume: 3, Issue:7

    The insulinomimetic activity of a Zn(ii) complex is reported. The effects of the Zn(ii) complex with ascorbic acid (Vitamin C; VC), methylmethionine sulfonium chloride (Vitamin U; VU) and l-carnitine were assessed in diet-induced metabolic syndrome model rats. Zn(VU)(2)Cl(2) and Zn(VC)Cl(2) were suggested to be useful supplementary materials for preventing metabolic syndrome by reducing visceral adipose tissues or accelerating blood fluidity.

    Topics: Adipocytes; Adipose Tissue; Animals; Ascorbic Acid; Body Weight; Carnitine; Cell Separation; Diet; Disease Models, Animal; Fatty Acids; Feeding Behavior; Glucose; Inhibitory Concentration 50; Insulin; Metabolic Syndrome; Rats; Vitamin U; Zinc

2011
Generalized impairment of vasodilator reactivity during hyperinsulinemia in patients with obesity-related metabolic syndrome.
    American journal of physiology. Endocrinology and metabolism, 2010, Volume: 299, Issue:6

    Defective insulin-dependent vasodilation might contribute importantly to metabolic and vascular abnormalities of the metabolic syndrome (MetS). However, despite extensive investigation, the precise mechanisms involved in insulin's vasoactive effects have not been fully elucidated. Therefore, this study sought to better characterize insulin's physiological actions on vascular reactivity and their potential derangement in the MetS. Forearm blood flow responses to graded doses of acetylcholine, sodium nitroprusside, and verapamil were assessed by strain-gauge plethysmography in patients with obesity-related MetS (n = 20) and in matched controls (n = 18) before and after intra-arterial infusion of insulin (0.2 mU·kg(-1)·min(-1)). Possible involvement of increased oxidative stress in the impaired insulin-stimulated vasodilator responsiveness of patients with MetS (n = 12) was also investigated using vitamin C (25 mg/min). In control subjects, significant potentiation of the vasodilator responses to acetylcholine, nitroprusside, and verapamil was observed after insulin infusion (all P < 0.05). However, no significant change in vasodilator reactivity to either of these drugs was observed following hyperinsulinemia in patients with MetS (all P > 0.05). Interestingly, administration of vitamin C to patients with MetS during hyperinsulinemia significantly enhanced the vasodilator responsiveness to acetylcholine, nitroprusside, and verapamil (all P < 0.05 vs. hyperinsulinemia alone). In conclusion, insulin exerts a generalized facilitatory action on vasodilator reactivity, and this effect is impaired in patients with MetS likely because of increased oxidative stress. Given the importance of vasodilator reactivity in affecting glucose disposal and vascular homeostasis, this defect may then contribute to the development of metabolic and vascular complications in insulin-resistant states.

    Topics: Acetylcholine; Analysis of Variance; Ascorbic Acid; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Female; Forearm; Glutathione; Humans; Hyperinsulinism; Insulin; Interleukin-6; Male; Metabolic Syndrome; Nitroprusside; Obesity; Regional Blood Flow; Tumor Necrosis Factor-alpha; Vasodilation; Vasodilator Agents; Verapamil

2010
Key functions of the energetic regulation are implicated in vitamin C action.
    Acta physiologica (Oxford, England), 2009, Volume: 195, Issue:4

    Topics: Animals; Ascorbic Acid; Catecholamines; Dietary Fats; Energy Metabolism; Humans; Insulin Resistance; Lipolysis; Metabolic Syndrome; Motor Activity; Obesity; Rats

2009
Effect of diesel exhaust inhalation on antioxidant and oxidative stress responses in adults with metabolic syndrome.
    Inhalation toxicology, 2009, Volume: 21, Issue:13

    Traffic-related air pollution is associated with cardiovascular morbidity and mortality. Although the biological mechanisms are not well understood, oxidative stress may be a primary pathway. Subpopulations, such as individuals with metabolic syndrome (MeS), may be at increased risk of adverse effects associated with air pollution. Our aim was to assess the relationship between exposure to diesel exhaust (DE) and indicators of systemic antioxidant and oxidative responses in adults with MeS. We hypothesized that DE exposure would result in greater oxidative stress and antioxidant responses compared with filtered air (FA).. Ten adult subjects with MeS were exposed on separate days for two hours to FA or DE (at 200microg/m3), in a double blind, crossover experiment. Urinary 8-isoPGF2alpha (F2-isoprostanes), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were assessed as markers of oxidative stress at 3 hrs and 22 hrs, respectively, after exposure initiation. To assess the short-term antioxidant response we analyzed plasma ascorbic acid (AA) 90 minutes after exposure initiation. All outcomes were compared to pre-exposure levels, and mean changes were compared between FA and DE exposures.. Mean changes in urinary F2-isoprostanes (ng/mg creatinine), (-0.05 [95% CI = -0.29, 0.15]), and 8-OHdG (microg/g creatinine) (-0.09 [-0.13, 0.31]), were not statistically significant. Mean changes in plasma AA (mg/dl) were also not significant (-0.02 [-0.78, 0.04]).. In this carefully controlled experiment, we did not detect significant changes in oxidative stress or systemic antioxidant responses in subjects with MeS exposed to 200microg/m3 DE.

    Topics: 8-Hydroxy-2'-Deoxyguanosine; Adolescent; Adult; Age Factors; Antioxidants; Ascorbic Acid; Biomarkers; Creatinine; Cross-Over Studies; Deoxyguanosine; Double-Blind Method; F2-Isoprostanes; Female; Follow-Up Studies; Humans; Inhalation Exposure; Male; Metabolic Syndrome; Middle Aged; Oxidative Stress; Vehicle Emissions; Young Adult

2009
The metabolic syndrome and antioxidant concentrations: findings from the Third National Health and Nutrition Examination Survey.
    Diabetes, 2003, Volume: 52, Issue:9

    Oxidative stress may play a role in the pathophysiology of diabetes and cardiovascular disease, but little is known about antioxidant status among individuals with the metabolic syndrome who are at high risk for developing these conditions. Using data from the Third National Health and Nutrition Examination Survey (1988-1994), we compared circulating concentrations of vitamins A, C, and E; retinyl esters; five carotenoids; and selenium in 8,808 U.S. adults aged > or = 20 years with and without the metabolic syndrome. After adjusting for age, sex, race or ethnicity, education, smoking status, cotinine concentration, physical activity, fruit and vegetable intake, and vitamin or mineral use, participants with the metabolic syndrome had significantly lower concentrations of retinyl esters, vitamin C, and carotenoids, except lycopene. With additional adjustment for serum lipid concentrations, vitamin E concentrations were significantly lower in participants with the metabolic syndrome than those without the syndrome. Retinol concentrations were similar between the two groups. After excluding participants with diabetes, the results were very similar. Consumption of fruits and vegetables was also lower among people with the metabolic syndrome. Adults with the metabolic syndrome have suboptimal concentrations of several antioxidants, which may partially explain their increased risk for diabetes and cardiovascular disease.

    Topics: Adult; Antioxidants; Ascorbic Acid; beta Carotene; Carotenoids; Esters; Female; Fruit; Humans; Male; Metabolic Syndrome; Middle Aged; Nutrition Assessment; Prevalence; Vegetables; Vitamin A; Vitamin E

2003