Andréa Name Colado Simão

Influence of uric acid and γ-glutamyltransferase on total antioxidant capacity and oxidative stress in patients with metabolic syndrome

OBJECTIVE Metabolic syndrome (MS) is a cluster of risk factors for cardiovascular disease related mainly to insulin resistance, but also to oxidative stress. Uric acid and gamma-glutamyltransferase (GGT) levels are also associated with MS and oxidative stress. This study was undertaken to assess the role of GGT and uric acid in adult patients with MS and its relation to oxidative stress and antioxidant defense. METHODS A total of 88 adults (67 with MS and 21 controls) were selected among ambulatory patients and workers of the University Hospital of Londrina, Paraná, Brazil. Oxidative stress was assessed by determination of thiobarbituric acid-reactive substances and tert-butyl hydroperoxide-initiated chemiluminescence and antioxidant defenses by total radical-trapping antioxidant parameter. RESULTS The MS group presented higher significant results (P < 0.0001) than the control group in all parameters of MS and uric acid and GGT levels and significant lower values (P < 0.0001) in high-density lipoprotein cholesterol levels. Thiobarbituric acid-reactive substances and total radical-trapping antioxidant parameter did not show statistically significant differences between groups. However, lipid hydroperoxides, evaluated by tert-butyl hydroperoxide-initiated chemiluminescence, showed higher significant results in the MS group (P = 0.045) than in the control group. Total antioxidant capacity did not decrease and thiobarbituric acid-reactive substances did not increase, probably due to increased uric acid (r = 0.239, P = 0.04) in the MS group. CONCLUSION The present study confirmed that GGT is a strong predictor of MS and that lipid peroxide measured by tert-butyl hydroperoxide-initiated chemiluminescence and GGT activity are reliable markers of oxidative stress in this syndrome.

Oxidative stress in multiple sclerosis patients in clinical remission: Association with the expanded disability status scale

Increased levels of oxidative stress markers and/or decreased levels of antioxidant molecules have been described in patients with multiple sclerosis (MS). This imbalance has been implicated in demyelination and axonal damage. The aims of this study were to evaluate oxidative stress in MS patients and to verify its correlation with disability as assessed by the expanded disability status scale (EDSS). This case-controlled study included 91 patients with relapsing-remitting multiple sclerosis (RR-MS) and 196 healthy individuals matched by age, gender, ethnicity, smoking status, and body mass index. Oxidative stress was evaluated by tert-butyl hydroperoxide-initiated chemiluminescence (CL-LOOH), carbonyl protein, nitric oxide metabolites (NOx), total radical-trapping antioxidant parameter (TRAP), sulfhydryl groups of proteins and serum uric acid levels. MS patients exhibited higher plasma levels of CL-LOOH (p<0.0001) and carbonyl protein (p=0.0081), and lower plasma levels of NOx (p<0.0001), TRAP (p=0.0088), and sulfhydryl groups (p=0.0003) compared to the control subjects. A multivariate analysis showed an association between oxidative markers and the presence of MS. Patients with an EDSS >3.5 showed higher CL-LOOH than control subjects (p=0.0093). A positive correlation was observed between CL-LOOH and EDSS (r=0.3244, p=0.0026) and between carbonyl protein and EDSS (r=0.3012, p=0.0041). These results demonstrate that oxidative stress plays an important role in the physiopathology of MS progression.

Evaluation of Oxidative Stress in Overweight Subjects With or Without Metabolic Syndrome

Although oxidative stress is considered the underlying mechanism by which dysfunctional metabolism occurs in obese subjects, there are few studies on oxidative stress in overweight subjects. The objective of this study was to verify the influence of metabolic syndrome (MetS) on oxidative stress and antioxidant defense in overweight subjects. There were 123 subjects (50 in the control group and 73 in the overweight group) chosen to participate in this cross‐sectional study. The control group included 50 healthy individuals with a BMI between 20 and 24.9 kg/m2 and without MetS. The overweight group included 73 subjects with a BMI between 25 and 29.9 kg/m2. Overweight subjects were divided into two groups: with MetS (29 subjects) and without MetS (44 subjects). Control group and overweight group subjects without MetS showed no differences in oxidative stress parameters and total antioxidant capacity (TRAP). Overweight subjects with MetS had higher hydroperoxide concentrations measured by chemiluminescence compared to the control group (P < 0.05), higher hydroperoxide and hydrogen peroxide concentrations determined by ferrous oxidation‐xylenol orange assay compared to overweight subjects without MetS (P < 0.001), and higher advanced oxidation protein product (AOPP) concentrations (P < 0.001) compared to the other groups. AOPP was directly correlated with uric acid concentrations. Overweight subjects with MetS had lower TRAP concentrations compared to the control group (P < 0.001). In conclusion, this study showed that overweight subjects with MetS, in contrast to overweight subjects without MetS, have a redox imbalance characterized by increased plasma oxidation and reduced antioxidant capacity.

Association between soy and green tea (Camellia sinensis) diminishes hypercholesterolemia and increases total plasma antioxidant potential in dyslipidemic subjects

OBJECTIVE To evaluate the hypolipemic and antioxidant effects of soy and green tea alone and/or in association in dyslipidemic subjects. METHODS One hundred dyslipidemic individuals were allocated into four groups. The soy group ingested 50 g of soy (kinako) daily, and the green tea group ingested 3 g of green tea in 500 mL of water per day. A third group ingested 50 g of soy and 3 g of green tea daily, and the control group had a hypocholesterolemic diet. Evaluations were performed at baseline and after 45 and 90 d. Plasma levels of total cholesterol, high-density lipoprotein, and triacylglycerols were evaluated by automated methods. Low-density lipoprotein (LDL) cholesterol was calculated using the Friedewald equation. LDL was isolated by ultracentrifugation. Total plasma antioxidant capacity and plasma levels of total lipid hydroperoxides and those linked to LDL were evaluated by chemiluminescence. The results were expressed as median values and their 25th to 75th percentiles, with a 5% level of significance. RESULTS No significant difference occurred in LDL, high-density lipoprotein cholesterol, and triacylglycerol levels across groups. However, a statistically significant difference in total cholesterol occurred within the soy/green tea group 45 and 90 d after intervention. No statistically significant difference occurred in plasma levels of lipid hydroperoxides or those linked to LDL in any of the groups studied. All the groups that used soy and/or green tea presented increased total plasma antioxidant potential. CONCLUSION Soy and green tea, alone or in combination, increased the total antioxidant potential of hypercholesterolemic patients, whereas only the combination decreased total cholesterol levels.

Time course of skeletal muscle loss and oxidative stress in rats with walker 256 solid tumor

Reactive oxygen species oxidize proteins and modulate the proteasomal system in muscle‐wasting cancer cachexia. On day 5 (D5), day 10 (D10), and day 14 (D14) after tumor implantation, skeletal muscle was evaluated. Carbonylated proteins and thiobarbituric acid reactive substances were measured. Chemiluminescence was employed for lipid hydroperoxide estimation. Glutathione, superoxide dismutase, and total radical antioxidant capacity were evaluated. The proteasomal system was assessed by mRNA atrogin‐1 expression. Increased muscle wasting, lipid hydroperoxide, and superoxide dismutase, and decreased glutathione levels and total radical antioxidant capacity, were found on D5 in accordance with increased mRNA atrogin‐1 expression. All parameters were significantly modified in animals treated with α‐tocopherol. The elevation in aldehylde levels and carbonylated proteins observed on D10 were reversed by α‐tocopherol treatment. Oxidative stress may trigger signal transduction of the proteasomal system and cause protein oxidation. These pathways may be associated with the mechanism of muscle wasting that occurs in cancer cachexia. Muscle Nerve 42: 950–958, 2010

Disability in patients with multiple sclerosis: influence of insulin resistance, adiposity, and oxidative stress.

OBJECTIVE The aims of the present study were to report the prevalence of insulin resistance (IR) in patients with multiple sclerosis (MS); to verify differences in metabolic and inflammatory biomarkers, and oxidative stress in patients with MS with or without IR; and to assess if IR and adiposity are associated with disability in these patients. METHODS The study enrolled 110 patients with MS and 175 healthy individuals. Patients with MS were divided in those with IR (n = 44) and those without (n = 66). Metabolic and inflammatory markers, oxidative stress, and disability were evaluated by the Extended Disability Status Scale (EDSS). RESULTS IR prevalence was verified in 40% of the patients with MS and in 21.1% of the control group (odds ratio, 2.48; 95% confidence interval, 1.469-4.210; P = 0.0006). Patients with the disease and IR showed higher EDSS (P = 0.031), interleukin (IL)-6 (P = 0.028), IL-17 (P = 0.006), oxidative stress evaluated by tert-butyl hydroperoxide-initiated chemiluminescence (P = 0.029), and advanced oxidation protein products (P = 0.025) than those patients without IR. The multivariate analysis showed that disability was associated with IR evaluated by homeostasis model assessment of insulin resistance (P = 0.030) and adiposity evaluated by waist circumference (P = 0.0179) and body mass index (P = 0.0033). CONCLUSION This is the first study to demonstrate an increase IR prevalence and the association between IR and adiposity with disability assessed by EDSS in patients with MS. IR seems to be associated with chronic inflammatory process and oxidative stress in patients with MS. More studies are warranted to elucidate the mechanisms by which IR and adiposity could contribute to the progression and disability in patients with MS.

Beneficial effects of Lactobacillus plantarum on glycemia and homocysteine levels in postmenopausal women with metabolic syndrome

OBJECTIVE Metabolic syndrome (MetS) in postmenopausal women is an important risk factor for cardiovascular morbidity, especially stroke and coronary heart disease and mortality. Preventing and treating MetS would be useful in preventing disability and promoting normal aging. Previous human studies have found some beneficial effects of Lactobacillus species on some isolated parameters of MetS. Nevertheless, we are not aware, to date, of any study which has verified the influence of probiotics in patients with MetS. Therefore, the aim of the present study was to evaluate the influence of fermented milk with L. plantarum in the classical parameters related to MetS, as well as in other parameters related to cardiovascular risk in postmenopausal women. METHODS Twenty-four individuals were paired by age, ethnicity, and body mass index in two groups: Non-fermented milk (NFM = 12) 80 mL/d and fermented milk (FM = 12) 80 mL/d. Anthropometric and blood pressure measurements, biochemical, inflammatory, and immunologic biomarkers were measured. RESULTS Total cholesterol and γ-glutamyltranspeptidase had a significant reduction both in NFM (P = 0.043 and P = 0.036, respectively) and FM groups (P = 0.010 and P = 0.018, respectively) after 90 d, whereas low-density lipoprotein cholesterol showed a significant reduction in NFM group (P = 0.002) and trend in the FM group (P = 0.092). Glucose and homocysteine levels showed a significant reduction in the FM group compared with the NFM group (P = 0.037 and P = 0.019, respectively). In relation to inflammatory biomarkers, there was a significant decrease in interleukin-6 both in NFM (P = 0.032) and in FM (P = 0.001) groups. CONCLUSION FM with L. plantarum showed more favorable results than NFM in relation to cardiovascular risk factors in postmenopausal women with MetS.

Blood pressure decrease with ingestion of a soya product (kinako) or fish oil in women with the metabolic syndrome: role of adiponectin and nitric oxide.

The aim of the present study was to verify the effects of fish oil and a soya-based product on inflammatory markers and endothelial function measured by NO in women with the metabolic syndrome (MetS). A total of sixty-five women (mean age: 47·9 (SD 9·98) years) were studied in a 90-d parallel, randomised design. A control group maintained their usual diet; the second group received 29 g/d of soyabean (kinako); the third group received 3 g/d of fish oil n-3 fatty acids; and the fourth group received fish oil (3 g/d) and kinako (29 g/d). Anthropometric, blood pressure (BP), inflammatory markers, anti-inflammatory marker (adiponectin) and NO concentrations were evaluated. In relation to the baseline values, the group that received fish oil and kinako concomitantly presented a statistically significant decrease in systolic BP (SBP; P < 0·05), whereas there was a significant decrease in diastolic BP (DBP) in the control group (P < 0·05), kinako group (P < 0·01) and fish oil group (P < 0·01) after 90 d. There was a significant increase in adiponectin (P < 0·01) and NO values (P < 0·05) after 90 d in the kinako and fish oil groups. Differences between treatment groups verified a significant decrease (P < 0·05) in DBP in the kinako group after 90 d when compared to the results obtained from the fish oil and kinako groups. In conclusion, the findings of increased serum adiponectin and NO metabolite levels after 90 d, both in the fish oil and soya groups, reinforce the importance of the influence of adiponectin and NO levels on BP decrease in patients with the MetS.

Nitric oxide enhancement and blood pressure decrease in patients with metabolic syndrome using soy protein or fish oil.

OBJECTIVE To verify the effects of fish oil and soy on nitric oxide (NO) and blood pressure in patients with metabolic syndrome (MS). SUBJECTS AND METHODS Sixty women with MS were investigated in a parallel randomized design study. The first group maintained their usual diet; the second group received 25 g/day of soy; the third group received 3 g/day of n-3 fatty acids, and the fourth group the same amount previously cited of n-3 fatty acids and soy. RESULTS Serum nitric oxide metabolites showed significant increase after 90 days in the fish oil and soy groups. Systolic pressure reduced after 45 days of treatment with fish oil, whereas diastolic pressure decreased significantly throughout the study in the soy group. CONCLUSIONS NO increase and blood pressure reduction with fish oil or soy protein reinforce the importance of the influence of NO on blood pressure in patients with MS.

Reduced-energy cranberry juice increases folic acid and adiponectin and reduces homocysteine and oxidative stress in patients with the metabolic syndrome

The metabolic syndrome (MetS) comprises pathological conditions that include insulin resistance, arterial hypertension, visceral adiposity and dyslipidaemia, which favour the development of CVD. Some reports have shown that cranberry ingestion reduces cardiovascular risk factors. However, few studies have evaluated the effect of this fruit in subjects with the MetS. The objective of the present study was to assess the effect of reduced-energy cranberry juice consumption on metabolic and inflammatory biomarkers in patients with the MetS, and to verify the effects of cranberry juice concomitantly on homocysteine and adiponectin levels in patients with the MetS. For this purpose, fifty-six individuals with the MetS were selected and divided into two groups: control group (n 36) and cranberry-treated group (n 20). After consuming reduced-energy cranberry juice (0·7 litres/d) containing 0·4mg folic acid for 60 d, the cranberry-treated group showed an increase in adiponectin (P=0·010) and folic acid (P=0·033) and a decrease in homocysteine (P<0·001) in relation to baseline values and also in comparison with the controls (P<0·05). There was no significant change in the pro-inflammatory cytokines TNF-a, IL-1 and IL-6. In relation to oxidative stress measurements, decreased (P<0·05) lipoperoxidation and protein oxidation levels assessed by advanced oxidation protein products were found in the cranberry-treated group when compared with the control group. In conclusion, the consumption of cranberry juice for 60 d was able to improve some cardiovascular risk factors. The present data reinforce the importance of the inverse association between homocysteine and adiponectin and the need for more specifically designed studies on MetS patients.