Plasma Thiobarbituric Acid Reactive Substances Research Articles

α-Lipoic acid can improve endothelial dysfunction in subjects with impaired fasting glucose

Several studies showed that impairment of endothelium-dependent arterial dilation (EDAD) exists in subjects with impaired fasting glucose (IFG). The crucial mechanism of this endothelial dysfunction remains unclear. We hypothesized that oxidative stress may be partially responsible for the impairment in EDAD in subjects with IFG. Thus, the present study was designed to assess whether the antioxidant α-lipoic acid can improve endothelial dysfunction in subjects with IFG. Sixty subjects with newly diagnosed IFG and 32 healthy individuals with normal glucose tolerance were enrolled. Subjects were randomized into 2 groups: untreated experimental group (n = 30) and α-lipoic acid treatment group (n = 30, α-lipoic acid 600 mg via intravenous infusion once a day for 3 weeks). We measured EDAD at baseline and after 3 weeks of intervention. At baseline, EDADs in α-lipoic acid and untreated experimental groups were 4.03% and 4.14%, respectively, which were significantly lower than that in controls (5.72%) ( P < .001). After 3 weeks of intervention, there was a remarkable increase in EDAD (reaching 5.10%; ΔEDAD, 26.5%) ( P < .01) and a significant decrease in plasma thiobarbituric acid reactive substances (TBARS) (29.1%) ( P < .05) in IFG subjects treated with α-lipoic acid. Endothelium-dependent arterial dilation and TBARS remained unchanged before and after intervention in the untreated experimental group. The absolute changes in EDAD showed a significant negative correlation with the changes in TBARS ( r = −0.444, P = .014). Our data showed that IFG subjects have impaired endothelial function and that antioxidant α-lipoic acid can improve endothelial function through a decrease of oxygen-derived free radicals.

Lymphocyte enzymatic antioxidant responses to oxidative stress following high-intensity interval exercise

The purposes of this study were to 1) examine the immune and oxidative stress responses following high-intensity interval training (HIIT); 2) determine changes in antioxidant enzyme gene expression and enzyme activity in lymphocytes following HIIT; and 3) assess pre-HIIT, 3-h post-HIIT, and 24-h post-HIIT lymphocyte cell viability following hydrogen peroxide exposure in vitro. Eight recreationally active males completed three identical HIIT protocols. Blood samples were obtained at preexercise, immediately postexercise, 3 h postexercise, and 24 h postexercise. Total number of circulating leukocytes, lymphocytes, and neutrophils, as well as lymphocyte antioxidant enzyme activities, gene expression, cell viability (CV), and plasma thiobarbituric acid-reactive substance (TBARS) levels, were measured. Analytes were compared using a three (day) × four (time) ANOVA with repeated measures on both day and time. The a priori significance level for all analyses was P < 0.05. Significant increases in superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities were observed in lymphocytes following HIIT. No significant increases in lymphocyte SOD, CAT, or GPX gene expression were found. A significant increase in TBARS was found immediately post-HIIT on days 1 and 2. Lymphocyte CV in vitro significantly increased on days 2 and 3 compared with day 1. Additionally, there was a significant decrease in CV at 3 h compared with pre- and 24 h postexercise. These findings indicate lymphocytes respond to oxidative stress by increasing antioxidant enzyme activity. Additionally, HIIT causes oxidative stress but did not induce a significant postexercise lymphocytopenia. Analyses in vitro suggest that lymphocytes may become more resistant to subsequent episodes of oxidative stress. Furthermore, the analysis in vitro confirms that lymphocytes are more vulnerable to cytotoxic molecules during recovery from exercise.

The relationship between serum biotin and oxidant/antioxidant activities in bovine lameness

Serum biotin concentrations, erythrocyte superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) and plasma thiobarbituric acid reactive substances (TBARS) were measured in 36 dairy cows, 18 of them were healthy and served as control. In the 18 cows with lameness problems, there were 5 cows with interdigital necrobacillosis, 5 cows with subsolar abscessation, 2 cows with solar ulcers, 2 cows with white line disease, 2 cows with chronic laminitis and 2 cows with septic arthritis. The degree of lameness was estimated to be slight in 3 cows, moderate in 11 cows and severe in 4 cows. Plasma fibrinogen levels and TBARS concentrations were increased significantly ( P ⩽ 0.05) in lame cows compared to control group. The antioxidant enzymes GSH-Px, and CAT concentrations were increased significantly ( P ⩽ 0.05) in lame cows. The level of reduced glutathione and the activity of SOD were significantly decreased in affected cows compared to healthy ones. Serum biotin levels in healthy cows ranged from 2.25 to 3.5 ng/ml while in lame cows, biotin levels ranged from 1.17 to 2.3 ng/ml. Biotin levels correlated positively with blood GSH ( r = 0.870, P ⩽ 0.05), ( r = 0.735, P ⩽ 0.05) and with GSH-Px ( r = 0.539, P ⩽ 0.05), ( r = 0.637, P ⩽ 0.05) and with SOD ( r = 0.637, P ⩽ 0.05), ( r = 0.449, P ⩽ 0.05) and with catalase ( r = 0.533, P ⩽ 0.05), ( r = 0.585, P ⩽ 0.05) in both healthy and lameness affected subjects, respectively.

Mitochondrial DNA copy number correlates with oxidative stress and predicts mortality in nondiabetic hemodialysis patients

Oxidative stress is highly prevalent in hemodialysis patients and may contribute to atherosclerosis and mortality. The copy number of mitochondrial DNA (mtDNA) is affected by oxidative stress in blood circulation. This study aimed to test whether mtDNA copy number correlates with oxidative stress and predicts all-cause mortality in nondiabetic hemodialysis patients. Ninety-five nondiabetic hemodialysis patients and 95 healthy subjects were enrolled. Plasma thiobarbituric acid-reactive substances (TBARS) and plasma free thiol were used as indicators of oxidative stress and antioxidant defense, respectively. Mitochondrial DNA copy number in peripheral blood leukocytes was measured by determining relative amounts of mtDNA to nuclear DNA by quantitative real-time PCR. All-cause mortality of hemodialysis patient was recorded during a follow-up of 3 years. Nondiabetic hemodialysis patients showed higher TBARS levels, lower free thiol levels and higher mtDNA copy numbers compared with normal control subjects. The plasma TBARS level was a significant factor correlating positively to the mtDNA copy number (p=0.024). Patients with a mtDNA copy number higher than the median had a higher all-cause mortality than patients with a lower mtDNA copy number (17.0% vs. 4.2%; log-rank test: p=0.038). A 1-log increase in mtDNA copy number was independently related to an increase in the risk for mortality (hazard ratio 21.360; 95% confidence interval, 1.298-351.572). Nondiabetic hemodialysis patients had higher oxidative stress and mtDNA copy numbers than healthy subjects. The mtDNA copy number correlates with oxidative stress and predicts mortality in nondiabetic hemodialysis patients.

Development of nutritional iron deficiency in growing male rats: haematological parameters, iron bioavailability and oxidative defence

Despite Fe deficiency having been widely studied, the sequence of events in its development still remains unclear. The aim of the present study was to elucidate the effects of nutritional Fe-deficiency development on haematological parameters, Fe bioavailability and the enzymes involved in oxidative defence in recently weaned male Wistar albino rats. Control (C) and Fe-deficient (ID) groups were fed the AIN-93 G diet with a normal Fe level (45mg/kg diet) or with a low Fe level (5mg/kg diet), respectively, for 20, 30 or 40d. At day 20 serum Fe, serum ferritin and the saturation of transferrin decreased drastically, decreasing further in the course of Fe-deficiency development for the saturation of transferrin. The development of Fe deficiency did not affect plasma thiobarbituric acid-reactive substance production, or catalase (CAT) and glutathione peroxidase (GPx) activities in erythrocyte cytosol. Fe deficiency diminished hepatic Fe content and CAT and GPx activities in hepatic cytosol only at day the 20. However, in spite of the minor Fe deposits in the brain of ID rats, the CAT and GPx activities in the brain cytosolic fraction did not differ in any of the studied periods v. control rats. These results show that brain is a tissue that does not seem to depend on Fe levels for the maintenance of antioxidant defence mechanisms in the course of nutritional Fe deficiency.

Effect of Red Wine on Adipocytokine Expression and Vascular Alterations in Fructose-Fed Rats

Imbalance in adipocytokines secretion is related to the development of metabolic syndrome (MS). In addition, moderate consumption of red wine (RW) decreases the risk of cardiovascular disease. The aim of this study was to evaluate the effects of moderate consumption of RW or ethanol (E) on adiponectin and resistin expression, and vascular alterations in fructose-fed rats (FFRs) as an experimental model of MS. Thirty-day-old male Wistar rats were assigned to control (C), F (10% fructose in drinking water), F+E (4.5 ml/kg), and F+RW (35 ml/kg of Malbec RW containing 4.5 ml/kg E). E and RW were administered during the last 4 weeks of a 10-week period. RW administration to F rats was able to significantly decrease insulin resistance, mesenteric adipose tissue weight, and systolic blood pressure (SBP) compared to F group. F+E only reduced the SBP (P < 0.05 vs. F). F+RW also reduced aortic NAD(P)H-oxidase activity, NAD(P)H subunits Nox4 expression in mesenteric tissue, plasma thiobarbituric acid reactive substances (TBARS), and recovered plasma total antioxidant activity (TAA) compared to F and F+E groups (P < 0.05). Adiponectin expression decreased, whereas resistin, vascular cell adhesion molecules-1 (VCAM-1), and nuclear factor-κB (NF-κB) expression and vascular remodeling in mesenteric arteries were higher in F than in C group (P < 0.05). Only RW was able to partially reverse the aforementioned alterations. In this study, Malbec RW, but not alcohol alone, improved the balance of adipocytokines and attenuated the oxidative stress and vascular inflammation in a model of MS, suggesting that nonalcohol components of RW are responsible for the beneficial effects.

Oxidative Stress Status in Rats After Intermittent Exposure to Hypobaric Hypoxia

Programs of intermittent hypobaric hypoxia (IHH) exposure are used to raise hemoglobin concentration and erythrocyte mass. Although acclimation response increases blood oxygen transport capacity leading to a VO(2max) increase, the effects of reactive oxygen species (ROS) might determine the behavior of erythrocytes and plasma, thus causing a worse peripheral blood flow. The goals of the study were to establish the hematological changes and to discern whether an IHH protocol modifies the antioxidant/pro-oxidant balance in laboratory rats. Male rats were subjected to an IHH program consisting of a daily 4-hour session for 5 days/week until completing 22 days of hypoxia exposure in a hypobaric chamber at a simulated altitude of 5000 m. Blood samples were taken at the end of the exposure period (H) and at 20 (P20) and 40 (P40) days after the end of the program, and compared to control (C), maintained at sea-level pressure. Hematological parameters were measured together with several oxidative stress indicators: plasma thiobarbituric acid reactive substances (TBARS) and erythrocyte catalase (CAT) and superoxide dismutase (SOD). Red blood cell (RBC) count, hemoglobin concentration and hematocrit were higher in H group as compared to all the other groups (p < 0.001). However, there were no significant differences between the 4 groups in any of the oxidative stress-related parameters. The absence of significant differences between groups indicates that our IHH program has little impact on the general redox status, even in the laboratory rat, which is more sensitive to hypoxia than humans. We conclude that IHH does not increase oxidative stress.

Protective role of curcumin in nephrotoxic oxidative damage induced by vancomycin in rats

Vancomycin (VAN) is a glycopeptide antibiotic which is active against gram positive bacteria including methicillin resistant Staphylococci. Free radicals are involved in the pathogenesis of vancomycin-induced nephrotoxicity. Therefore, the present study was conducted to investigate the antioxidant potential of curcumin (CUR) against the nephrotoxicity of vancomycin in male rats. Animals used in this study were divided into four groups; the first group was used as control, the second, third and fourth groups were treated orally with curcumin (200 mg/kg BW/day), vancomycin (200 mg/kg BW/day, i.p.), vancomycin plus curcumin, respectively. Curcumin was administered 2 weeks before and 1 week simultaneously with vancomycin. Results showed that thiobarbituric acid reactive substances (TBARS) in plasma and kidney tissue were significantly increased after vancomycin administration. While, the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in plasma and kidney tissue and the content of glutathione (GSH) in kidney tissue were decreased compared to control. Vancomycin significantly increased the levels of urea and creatinine. The presence of curcumin with vancomycin caused reduction in induction levels of TBARS in plasma and kidney, urea and creatinine. It ameliorated vancomycin-induced decrease in the activities of antioxidant enzymes and GSH. The presence of curcumin with vancomycin alleviated its nephrotoxic effects. It can be concluded that curcumin has beneficial influences and could be able to antagonize vancomycin nephrotoxicity.

Regulation of oxidative stress in response to acute aerobic and resistance exercise in HIV-infected subjects: a case–control study

Human immunodeficiency virus (HIV)-infected subjects have increased levels of oxidative stress which could impair immunological function and therefore contribute to the progression of AIDS. These characteristics are usually evaluated at rest and responses to exercise have yet to be evaluated. The aim of the present study was to assess the effect of a bout of aerobic exercise followed by resistance exercises on antioxidant system in HIV-infected and non-HIV subjects. There were included 14 cases (HIV-positive) and 14 controls (HIV-negative). The exercise protocol consisted of a single session of 20 minutes on a cycloergometer followed by a set of six resistance exercises. The activity of glutathione S-transferase (GST) and catalase were measured in plasma samples, total glutathione (TGSH) and thiobarbituric acid reactive substances (TBARS) were measured in erythrocytes. T CD4+ cells, T CD8+, viral load, complete blood count, and white blood count were also assessed. All measurements were performed at three times: baseline, after aerobic exercise, and after resistance exercises. At baseline, the HIV group had lower GST activity than controls, but after the exercise session GST values were similar in both groups. Compared to the control group TGSH was significantly lower in the HIV group at baseline, after aerobic and resistance exercises. The control group presented higher TBARS values after aerobic exercise compared to the HIV group. The neutrophil count was lower in the HIV group after aerobic and resistance exercises. These data indicate that HIV-infected subjects had lower antioxidant activity at rest. Physical exercise stimulated the enzymatic activity similarly in both groups.

Dietary genistein and equol (4′, 7 isoflavandiol) reduce oxidative stress and protect rats against focal cerebral ischemia

High soy diets reduce injury in rat models of focal cerebral ischemia and are proposed as alternatives to hormone replacement therapy for postmenopausal women. The present study tests the hypothesis that the major soy isoflavone genistein and the daidzein metabolite equol are neuroprotective in transient focal cerebral ischemia in male and ovariectomized (OVX) female rats by inhibiting oxidative stress. Genistein is the primary circulating soy isoflavone in humans, whereas equol is the primary circulating isoflavone in rats. Male and OVX female Sprague-Dawley rats were fed an isoflavone-reduced diet alone or supplemented with genistein (500 ppm) or equol (250 ppm) for 2 wk prior to 90-min transient middle cerebral artery occlusion followed by reperfusion under isoflurane anesthesia. Indices of oxidative stress were determined 24 h after reperfusion, and cerebral injury was evaluated 3 days after reperfusion. Genistein and equol significantly reduced infarct size in both sexes. Further studies in OVX female rats revealed that this neuroprotection was accompanied by a decrease in NAD(P)H oxidase activity and superoxide levels in the brain. In addition, equol reduced plasma thiobarbituric acid reactive substances, and neurological deficits up to 7 days after injury. There were no significant differences in cerebral blood flow among treatment groups. In conclusion, dietary soy isoflavones are neuroprotective in transient focal cerebral ischemia in male and OVX female rats. These isoflavones may protect the brain via increases in endogenous antioxidant mechanisms and reduced oxidative stress.

Caloric restriction improves endothelial dysfunction during vascular aging: Effects on nitric oxide synthase isoforms and oxidative stress in rat aorta

Aging is characterized by activation of inducible over endothelial nitric oxide synthase (iNOS and eNOS), impaired antioxidant activity and increased oxidative stress, which reduces nitric oxide bioavailability and causes endothelial dysfunction. Caloric restriction (CR) blunts oxidative stress. We investigated whether CR impacts endothelial dysfunction in aging and the underlying mechanisms. Aortas from young (YC, 6 months of age) and old (OC, 24 months of age) rats ad-libitum fed and from old rats caloric-restricted for 3-weeks (OR, 26%) were investigated. Endothelium-dependent vasorelaxation was impaired in OC, associated with reduced eNOS and increased iNOS expression (P < 0.05). Aortic nitrite was similar in OC and YC, but the contribution of calcium-independent NOS to total NOS activity was increased whereas that of calcium-dependent NOS was reduced (p ≤ 0.0003). Plasma thiobarbituric acid-reactive substances (TBARS) were elevated in OC as well as aortic nitrotyrosine (P < 0.05). Expression of manganese superoxide dismutase (MnSOD) and total SOD activity were impaired in OC (P < 0.05 vs. YC), whereas copper-zinc (CuZn) SOD expression was similar in OC and YC. CR restored endothelial dysfunction in old rats, reduced iNOS expression, total nitrite and calcium-independent NOS activity in aorta (P < 0.05) without changes in eNOS expression and calcium-dependent NOS activity. Sirtuin-1 expression did not differ among groups. Plasma TBARS and aortic nitrotyrosine were reduced (P < 0.05) in OR compared with OC. In OR CuZnSOD protein and SOD activity increased (P < 0.05) without changes in MnSOD expression. Short-term CR improves age-related endothelial dysfunction. Reversal of altered iNOS/eNOS ratio, reduced oxidative stress and increased SOD enzyme activity rather than enhanced NO production appear to be involved in this effect.

Cardiac troponins and oxidative stress markers in non-pregnant, pregnant and preeclampsia women

Free radicals play an important role in the pathogenesis of tissue damage in many clinical disorders, including atherosclerosis. This study was to investigate lipids and oxidative stress markers among women with 50 healthy non-pregnant compare with 50 healthy pregnant and 50 pregnancy-induced hypertensive subjects and correlate with cardiac troponin I (cTnI) and troponin T (cTnT). The level of plasma thiobarbituric acid reactive substances (TBARS), cTnI and cTnT levels significantly increase in pregnancy-induced hypertension compare with other groups. The level of lipids significantly altered in pregnancy-induced hypertension. Conversely, the activities of both enzymatic and non-enzymatic antioxidants were significantly decreased in pregnancy-induced hypertension compared to nonpregnant and healthy pregnant. Our data suggest that there is an imbalance between lipoperoxidation and antioxidants levels during pregnancy and preeclampsia. Serum cTnI and cTnT are elevated in women with pregnancy-induced hypertension indicating some degree of cardiac myofibrillar damage and cardiac dysfunction.

Beneficial effects of fructo-oligosaccharides supplementation on fecal bifidobacteria and index of peroxidation status in constipated nursing-home residents—A placebo-controlled, diet-controlled trial

Objective This study assessed effects of fructo-oligosaccharides (FOS) supplementation on fecal bifidobacteria, lipid peroxidation index, indices of nutritional status, and whether effects of FOS were sustained after its withdrawal in constipated nursing-home residents. The associations of fecal bifidobacteria and blood measurements were also examined. Methods Six men and four women participated in a double-blind, diet-controlled study that consisted of a 4-wk placebo (3 mL of fructose syrup) period, a 4-wk FOS (10 g/d) period, and a 4-wk post-FOS period. Stools were collected during the last week of each period to determine the microflora and fecal weight. Fasting blood was collected at the end of each period and analyzed for thiobarbituric acid-reactive substances (TBARS) and biochemical indices. Results Fecal counts (log counts/gram of dry feces) and daily fecal output of bifidobacteria significantly increased with FOS compared with placebo. The effect on bifidobacteria output was sustained in the post-FOS period. Plasma TBARS concentration was reduced by 16% and 21% in the FOS and post-FOS periods, respectively, compared with that in the placebo period. The plasma cholesterol level was significantly lowered by 7% in the FOS and post-FOS periods compared with that in the placebo period. The increases in fecal bifidobacteria output during the FOS period (log colony-forming units per day) were associated with decreases in plasma TBARS and plasma cholesterol, respectively. Conclusion Supplementation of FOS increases the daily output of bifidobacteria and decreases plasma TBARS and cholesterol concentrations in constipated nursing-home elderly residents and these effects remained at the end the post-FOS period.

Effect of synergic dietary calcium enrichment and induced ferropenic anemia on antioxidant enzymes activity in rats

Objective The aim of this study was to examine the synergism of dietary calcium enrichment (added to goat's or cow's milk) and induced nutritional ferropenic anemia on oxidative status. Methods Control rats and rats with induced nutritional ferropenic anemia were fed for 14 d with diets containing normal (5000 mg/kg) or double (10 000 mg/kg) the recommended calcium content. Thiobarbituric acid-reactive substances in plasma were measured, as were the activities of the antioxidant enzyme catalase, copper/zinc superoxide dismutase, and glutathione peroxidase in erythrocyte cytosol. Results Dietary calcium enrichment did not affect oxidative stress as assessed by thiobarbituric acid-reactive substances; however, it significantly upregulated the activities of some antioxidant enzymes examined in the erythrocyte cytosol. In particular, adding calcium to standard or milk-based diets significantly increased glutathione peroxidase activity in control and anemic rats and copper/zinc superoxide dismutase activity in control rats. Conclusion The increased activities of glutathione peroxidase and copper/zinc superoxide dismutase induced by dietary calcium enrichment suggest that calcium supplementation may protect against oxidative stress even in nutritionally induced ferropenic anemia.

Tempol, a superoxide dismutase mimetic, prevents cerebral vessel remodeling in hypertensive rats

Increased reactive oxygen species (ROS) production is involved in the pathogenesis of hypertension and stroke. The effects of ROS on cerebral vessels from hypertensive rats have not been studied. We hypothesized that tempol, a superoxide dismutase mimetic, would prevent middle cerebral artery (MCA) remodeling in stroke-prone spontaneously hypertensive rats (SHRSP). Six-week-old male SHRSP were treated with tempol (1 mM) for 6 weeks. The MCA was then removed and mounted in a pressure myograph to study tone generation, vessel reactivity, and passive vessel structure. Data are shown as mean ± SEM, tempol vs. control. Plasma thiobarbituric acid reactive substances (TBARS) were decreased by tempol treatment (14.15 ± 1.46 vs. 20.55 ± 1.25 nM of malondialdehyde [MDA]/ml, p = 0.008). Maximum serotonin-induced constriction was increased by tempol treatment, without changes in dilation to adenosine diphosphate or tone generation. At an intralumenal pressure of 80 mm Hg, tempol caused a dramatic increase in the MCA lumen diameter (246 ± 5 vs. 207 ± 3 μm, p < 0.001), outer diameter (281 ± 5 vs. 241 ± 3 μm, p < 0.001), lumen cross-sectional area, and vessel cross-sectional area. Collagen IV mRNA expressions were increased by 2.4-fold after tempol treatment. These results suggest that ROS are involved in the remodeling of the cerebral vasculature of SHRSP and that ROS scavenging can attenuate this process.

Lack of both bradykinin B1 and B2 receptors enhances nephropathy, neuropathy, and bone mineral loss in Akita diabetic mice

An insertion polymorphism of the angiotensin-I converting enzyme gene (ACE) is common in humans and the higher expressing allele is associated with an increased risk of diabetic complications. The ACE polymorphism does not significantly affect blood pressure or angiotensin II levels, suggesting that the kallikrein-kinin system partly mediates the effects of the polymorphism. We have therefore explored the influence of lack of both bradykinin receptors (B1R and B2R) on diabetic nephropathy, neuropathy, and osteopathy in male mice heterozygous for the Akita diabetogenic mutation in the insulin 2 gene (Ins2). We find that all of the detrimental phenotypes observed in Akita diabetes are enhanced by lack of both B1R and B2R, including urinary albumin excretion, glomerulosclerosis, glomerular basement membrane thickening, mitochondrial DNA deletions, reduction of nerve conduction velocities and of heat sensation, and bone mineral loss. Absence of the bradykinin receptors also enhances the diabetes-associated increases in plasma thiobarbituric acid-reactive substances, mitochondrial DNA deletions, and renal expression of fibrogenic genes, including transforming growth factor beta1, connective tissue growth factor, and endothelin-1. Thus, lack of B1R and B2R exacerbates diabetic complications. The enhanced renal injury in diabetic mice caused by lack of B1R and B2R may be mediated by a combination of increases in oxidative stress, mitochondrial DNA damage and over expression of fibrogenic genes.

Aqueous Garlic Extracts Prevent Oxidative Stress and Vascular Remodeling in an Experimental Model of Metabolic Syndrome

The organosulfur profile and the effect on oxidative stress and vascular remodeling in fructose-fed rats (FFR) were evaluated in Fuego INTA and Morado INTA garlic cultivars. Wistar rats were fed either normal rat chow (control) or the same diet plus 10% fructose in drinking water. During the last 6 weeks of a 12 week period of the corresponding diet, a subgroup of control and FFR received an aqueous extract of Fuego INTA and Morado INTA. Fuego INTA showed higher levels of total thiosulfinates, allicin, and pungency than Morado INTA. FFR showed an increase of systolic blood pressure, aortic NAD(P)H oxidase activity, plasma thiobarbituric acid reactive substances, and vascular remodeling that was significantly reduced after both garlic administrations. The beneficial effect was slightly higher when Fuego INTA was administered. Both aqueous garlic extracts prevent oxidative stress and vascular remodeling in rats with metabolic syndrome, suggesting the existence of slight differences among cultivars.

The Dietary Supplement Protandim® Decreases Plasma Osteopontin and Improves Markers of Oxidative Stress in Muscular Dystrophy Mdx Mice

ABSTRACT.Therapeutic options for Duchenne muscular dystrophy (DMD), the most common and lethal neuromuscular disorder in children, remain elusive. Oxidative damage is implicated as a pertinent factor involved in its pathogenesis. Protandim® is an over-the-counter supplement with the ability to induce antioxidant enzymes. In this study we investigated whether Protandim® provided benefit using surrogate markers and functional measures in the dystrophin-deficient (mdx) mouse model of DMD. Male 3-week-old mdx mice were randomized into two treatment groups: control (receiving standard rodent chow) and Protandim®-supplemented standard rodent chow. The diets were continued for 6-week and 6-month studies. The endpoints included the oxidative stress marker thiobarbituric acid-reactive substances (TBARS), plasma osteopontin (OPN), plasma paraoxonase (PON1) activity, H&E histology, gadolinium-enhanced magnetic resonance imaging (MRI) of leg muscle and motor functional measurements. The Protandim® chow diet in mdx mice for 6 months was safe and well tolerated. After 6 months of Protandim®, a 48% average decrease in plasma TBARS was seen; 0.92 nmol/mg protein in controls versus 0.48 nmol/mg protein in the Protandim® group (p = .006). At 6 months, plasma OPN was decreased by 57% (p = .001) in the Protandim®-treated mice. Protandim® increased the plasma antioxidant enzyme PON1 activity by 35% (p = .018). After 6 months, the mdx mice with Protandim® showed 38% less MRI signal abnormality (p = .07) than mice on control diet. In this 6-month mdx mouse study, Protandim® did not significantly alter motor function nor histological criteria.

Influence of fish oil or folate supplementation on the time course of plasma redox markers during pregnancy

Maternal supplementation with long-chain PUFA, to improve infant neurological development, might cause additional increase of oxidative stress. Pregnant women aged 18-41 years were randomised into one of four supplementation groups. From week 22 on, they received supplements containing either modified fish oil (n 69), 5-methyl-tetrahydro-folate (n 65), both (n 64), or placebo (n 72). Plasma Trolox-equivalent antioxidative capacity (TEAC), concentrations of alpha-tocopherol, retinol, beta-carotene, free thiol groups, uric acid and thiobarbituric acid-reactive substances (TBARS) were determined at weeks 20 and 30 and at delivery. The studied antioxidants showed no significant differences between the four supplementation groups. At week 30 plasma TBARS levels were found to be significantly higher in the fish oil group (0.80 (sem 0.04) micromol/l) than in the folate (0.67 (sem 0.03) micromol/l; P = 0.024) and control (0.69 (sem 0.04) micromol/l; P = 0.01) groups. Concentrations of retinol and free thiol groups decreased during pregnancy, whereas uric acid increased and beta-carotene as well as TEAC showed only minor changes. Fish oil supplementation during the second half of pregnancy appears not to decrease antioxidant status. The increased TBARS levels at week 30 may indicate a period of increased oxidative stress in plasma at this time.

Preventive effect of caffeic acid on lysosomal dysfunction in isoproterenol‐induced myocardial infarcted rats

We evaluated the preventive effect of caffeic acid (CA) on lysosomal enzymes in isoproterenol (ISO)-treated myocardial infarcted rats. Male albino Wistar rats were pretreated with CA (15 mg/kg) daily for a period of 10 days. After the pretreatment period, ISO (100 mg/kg) was subcutaneously injected to rats twice at an interval of 24 h. The activity of serum creatine kinase-MB and lactate dehydrogenase was increased significantly (P < 0.05) in ISO-induced myocardial infarcted rats. The levels of plasma thiobarbituric acid reactive substances and lipid hydroperoxides were significantly (P < 0.05) increased, and the level of plasma-reduced glutathione was significantly (P < 0.05) decreased in ISO-induced myocardial infarcted rats. The activities of lysosomal enzymes (beta-glucuronidase, beta-N-acetylglucosaminidase, beta-galactosidase, cathepsin-B and cathepsin-D) were increased significantly (P < 0.05) in the serum and heart of ISO-induced myocardial infarcted rats. ISO induction also resulted in decreased stability of membranes, which was reflected by lowered activities of beta-glucuronidase and cathepsin-D in different fractions except cytosol. Pretreatment with CA (15 mg/kg) to ISO-treated rats significantly (P < 0.05) prevented the changes in the activities of cardiac marker enzymes, the levels of lipid peroxidation products, reduced glutathione and the activities of lysosomal enzymes in the serum, heart, and subcellular fractions. Oral treatment with CA (15 mg/kg) to normal control rats did not show any significant effect. Thus, the results of our study showed that CA prevented the lysosomal membrane damage against ISO-induced myocardial infarction. The observed effects of CA are due to membrane-stabilizing, antilipo peroxidative, and antioxidant effects.