Relation of serum total antioxidant status with metabolic risk factors in Korean adults

Soluble Transferrin Receptor, Antioxidant Status and Cardiometabolic Risk in Apparently Healthy Individuals

Body iron excess appears to be related to insulin resistance and cardiometabolic risk and increased oxidative stress might be involved in this relationship. Very few studies have described the association between soluble transferrin receptor (sTfR) levels and cardiometabolic risk in the general population or antioxidant status. There were 239 subjects (20−65 years old) included in this cross-sectional study. Linear regressions adjusting for BMI, menopausal status, insulin resistance (HOMA-IR), physical inactivity, alcohol intake and subclinical/chronic inflammation were used to describe the association between sTfR, total antioxidant capacity (TAC), and measures of cardio-metabolic risk. sTfR levels were positively associated with TAC in men (βeta [95% confidence interval ]: 0.31 [0.14 to 0.48]) and women (βeta = 0.24 [0.07 to 0.40]) in non-adjusted and adjusted models (p < 0.05). In men, sTfR levels were inversely associated with waist circumference (βeta [95% confidence interval]: −1.12 [−2.30 to −0.22]) and fasting glucose (−2.7 (−4.82 to −0.57), and positively with LDL cholesterol (12.41 (6.08 to 18.57) before and after adjustments for confounding variables. LDL cholesterol had a significant and positive association with TAC in non-adjusted and adjusted models in men (p < 0.05). sTfR levels are significantly associated with antioxidant status and a few specific cardio-metabolic risk variables, independently of covariates that included serum ferritin and hepcidin. This might imply that iron biomarkers in regard to cardiometabolic risk reflect physiological contexts other than iron metabolism.

Comparison of the Effects of Brazil Nut Oil and Soybean Oil on the Cardiometabolic Parameters of Patients with Metabolic Syndrome: A Randomized Trial

Recent evidence suggests that replacing saturated fat with unsaturated fat is beneficial for cardiovascular health. This study compared the effects of Brazil nut oil (BNO) and soybean oil (SO) supplementation for 30 days on anthropometric, blood pressure, biochemical, and oxidative parameters in patients with metabolic syndrome (MS). Thirty-one patients with MS were randomly allocated to receive 30 sachets with 10 mL each of either BNO (n = 15) or SO (n = 16) for daily supplementation. Variables were measured at the beginning of the study and after 30 days of intervention. No change in anthropometric and blood pressure variables were observed (p > 0.05). Total (p = 0.0253) and low-density lipoprotein (p = 0.0437) cholesterol increased in the SO group. High-density lipoprotein cholesterol decreased (p = 0.0087) and triglycerides increased (p = 0.0045) in the BNO group. Malondialdehyde levels decreased in the BNO group (p = 0.0296) and total antioxidant capacity improved in the SO group (p = 0.0110). Although the addition of oils without lifestyle interventions did not affect anthropometric findings or blood pressure and promoted undesirable results in the lipid profile in both groups, daily supplementation of BNO for 30 days decreased lipid peroxidation, contributing to oxidative stress reduction.

Association between inflammation, oxidative stress, vitamin D, copper and zinc with pre-obesity and obesity in school children from the city of Podgorica, Montenegro

Background Childhood obesity is a serious health condition with increasing rates worldwide. The aim of this study was to investigate the association between inflammation, oxidative stress, vitamin D, copper and zinc in pre-obese and obese children compared to controls. Methods The study involved 202 children aged 7-15 years (63.9% boys), randomly chosen from 10 elementary schools in Podgorica, Montenegro. Participants were divided into three groups according to their nutritional status (International Obesity Task Force [IOTF] criteria): normal-weight (42.1%), pre-obese (40.6%) and obese (17.3%). Serum biochemical analyses were performed (C-reactive protein [CRP], retinol-binding protein [RBP], total antioxidant status [TAS], total vitamin D [VD], copper and zinc). Results Serum TAS and CRP concentrations were higher in pre-obese and obese children compared to controls (p < 0.001). Serum VD concentrations were lower in pre-obese and obese children compared to their normal-weight peers (p = 0.027 and p = 0.054, respectively). Copper, zinc and RBP concentrations did not differ significantly among the groups (p > 0.05). In pre-obese and obese children, a positive correlation was found between CRP and copper (r = 0.305, p = 0.011 and r = 0.440, p = 0.013, respectively), and TAS and RBP (r = 0.528, p < 0.001 and r = 0.434, p = 0.015, respectively). Standard regression analyses showed that CRP and TAS increase (p < 0.001) whereas VD decreases (p = 0.011) with the body mass index (BMI). Conclusions We show that pre-obesity and obesity in childhood are positively associated with oxidative stress and inflammation, and inversely associated with VD status. Copper and zinc concentrations were not associated with excess fat in children.

Evaluation of matrix metalloproteinase, myeloperoxidase, and oxidative damage in mesenteric ischemia-reperfusion injury

BACKGROUND

In this study, we investigated the alterations of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinases (TIMPs), acute inflammation, and oxidative damage in the circulatory system and the intestine in response to mesenteric ischemia/reperfusion (I/R).

METHODS

Twenty-one rats were divided randomly into the following three groups (n = 7 in each group): a sham group (CG), an ischemic group (IG), and an I/R group (I/RG). MMP-9, TIMP-1, and myeloperoxidase (MPO) were measured using the enzyme-linked immunosorbent assay method, and lipid peroxidation (quantified as thiobarbituric acid reactive substances (TBARS) content), ischemia-modified albumin, the prooxidant-antioxidant balance (PAB), and ferric-reducing antioxidant power (FRAP) were measured spectrophotometrically. The degree of intestinal injury was evaluated according to the Chiu scoring system.

RESULTS

A significant difference between the mean serum TIMP-1 and MMP-9 levels and the alanine transaminase activity was found among the groups. Compared with the I/RG group a significant difference in the mean tissue MMP-9, MPO, and TBARS levels in addition to the PAB and FRAP was found between the CG and IG groups. The level of MMP-9 also demonstrated a strong, positive, and valid correlation with the TBA-RS levels. A significant morphological change was observed in both the IG and the I/RG groups. The degree of intestinal injury was more severe in the I/R group and was characterized by either villous denudation or villous loss.

CONCLUSIONS

These results suggest that MMP-9, TIMP-1, MPO, and oxidative stress may be important in the intestinal injury development that is induced by acute mesenteric I/R in a rat model. MMP-9 overexpression may increase the extent of intestinal villous loss, particularly when MMP-9 is upregulated by the TBARS present in the intestinal injury.

Measurement of antioxidant capacity using the biological antioxidant potential test and its role as a predictive marker of metabolic syndrome

BACKGROUND/AIMS

Oxidative stress increases the risk of cardiovascular complications of metabolic syndrome (MetS). This study was conducted to examine the difference in antioxidant capacity according to the presence of MetS, and to characterize the association between antioxidant capacity and MetS-related factors.

METHODS

We used the biological antioxidant potential (BAP) test to estimate antioxidant capacity. The BAP test has recently been used as an indicator of antioxidant capacity. We measured BAP levels in 45 patients with MetS (mean age, 44.6 ± 1.1 years) and 47 age- and sex-matched controls (mean age, 42.7 ± 1.1 years). To evaluate the association between antioxidant capacity and MetS, adiponectin, high-sensitivity C-reactive protein (hs-CRP), interleukin-6, tumor necrosis factor-α, and homeostatic model assessment for insulin resistance (HOMA-IR), linear regression and logistic analyses were performed.

RESULTS

The mean BAP of the MetS group (1,937.3 ± 36.5 µmol/L) was significantly lower than that of the non-MetS group (2,101.7 ± 29.5 µmol/L). Also, the mean BAP was low in persons having low high density lipoprotein and high triglyceride. Reduced antioxidant capacity was significantly associated with adiponectin, HOMA-IR and hs-CRP after adjusting for age and sex. The odds ratios for MetS with BAP, log adiponectin, log HOMA-IR, and log hs-CRP were 0.63 (95% confidence interval [CI], 0.49 to 0.82), 0.22 (0.10 to 0.51), 14.24 (4.35 to 46.58), and 1.93 (1.36 to 2.75), respectively.

CONCLUSIONS

Persons with MetS showed reduced antioxidant capacity. We identified relationships between antioxidant capacity measured by BAP test and MetS, as well as MetS-related factors, such as insulin resistance, hs-CRP, and adiponectin.

The association of oxidative stress markers with conventional risk factors in the metabolic syndrome

BACKGROUND AND AIMS

The metabolic syndrome (MetS) is a common and complex disorder that consists of various abnormalities, including dyslipidemia, obesity, hypertension and hyperglycemia. We investigated the relationships between the levels of advanced protein oxidation products (AOPPs), the total antioxidant capacity (TAC) and the pro-oxidant-antioxidant balance (PAB) in MetS patients.

METHODS

A total of 55 patients (37 women, 18 men) with MetS and 20 healthy controls (14 women, 6 men) with a body mass index (BMI) less than 25 kg/m(2) were enrolled in the study. Colorimetric methods were used to determine the levels of AOPPs, the TAC, and the PAB.

RESULTS

AOPP, TAC, and PAB values were significantly higher in patients with MetS than in control subjects (p<0.001, p=0.050, and p<0.001, respectively). A positive correlation was observed between the AOPP levels and the glucose, triglyceride, insulin and HOMA-IR levels. PAB values also exhibited significant positive correlations with diastolic blood pressure and fibrinogen levels. Logistic regression analysis revealed that higher serum PAB values were positively and independently associated with the MetS (odds ratio: 1.110; 95% confidence interval: 1.006-1.224; P<0.37).

CONCLUSIONS

Increased AOPP levels and higher PAB values are likely to be a result of oxidative stress, a condition in which an imbalance occurs between the production and inactivation of reactive oxygen species. In addition, it appears that serum PAB values may accurately reflect the levels of oxidative stress in MetS patients.

Epidermal growth factor receptor expression in mice skin upon ultraviolet B exposure - Seborrheic Keratosis as a coincidental and unique finding

Background:

Ultraviolet B (UVB) is the most damaging component of sunlight. It rapidly activates the epidermal growth factor receptor (EGFR) and generates reactive oxygen species (ROS) in excessive quantities that quickly overwhelm tissue antioxidants.

Setting and Design:

To demonstrate the effects of UVB radiation on EGFR expression in mice skin and to evaluate the role of antioxidants in the exposed group.

Materials and Methods:

After obtaining the approval of the ethical committee, forty mice from BALB/c strain were used in this experiment and were allocated into 3 groups; 10 (control group); 15 (exposure group); and 15 (exposed and treated with antioxidants). Antioxidants were administered through subcutaneous injection. Skin biopsies from all groups were stained with EGFR antibodies. Total antioxidant status (TAS) was evaluated in all groups.

Statistical Analysis:

The data obtained were analyzed using ANOVA, Duncan's test, and Pearson's Correlation.

Results:

The highest EGFR expression in exposure group was of score 3⁺ (53%). The highest EGFR expression in treatment group was score 0 (40%). Apoptotic bodies and dermal mast cells increased in exposure group while decreased in treatment group. The mean values for TAS were measured for each group; control group = 1.2 mmol/l; exposure group = 0.87 mmol/l; treatment group =1.3 mmol/l.

Conclusions:

UVB led to Seborrheic Keratosis (SK) in mice through enhancement of EGFR expression. Antioxidants effectively reduced UVB-induced SK, reduced epidermal changes, apoptotic bodies, and decreased dermal mast cells. TAS measurement declined in exposure group, while it was within normal range in most treated cases.

Vitamin C and fibre consumption from fruits and vegetables improves oxidative stress markers in healthy young adults

The aim of the present cross-sectional study was to assess the potential relationships between fruit and vegetable (FV) consumption and some oxidative stress markers in young adults, with particular emphasis on fibre and vitamin C intake. The study enrolled 246 healthy subjects (eighty-eight men and 158 women), with a mean age of 22 (sd 3) years and a mean BMI of 21·9 (sd 2·8) kg/m2. Dietary intake, anthropometry, blood pressure, lifestyle features and blood biochemical data were assessed with validated procedures. Those subjects in the highest tertile (T) of FV consumption ( ≥ 705 g/d) had statistically lower oxidised LDL (ox-LDL) concentrations as well as higher plasma total antioxidant capacity (TAC) and glutathione peroxidase (GPx) activity (P for trend <0·05), after adjusting for sex, age, energy intake, physical activity, smoking, BMI, vitamin supplement use and other confounding factors. Moreover, plasma ox-LDL concentrations showed a decreasing trend and TAC an increasing trend across tertiles of fibre (T3: ≥14 g/d) and vitamin C (T3: ≥150 mg/d) from FV intake, while GPx activity was positively associated with vitamin C intake (P for trend < 0·05). In conclusion, greater FV consumption was independently associated with reduced ox-LDL as well as increased TAC and GPx activity in healthy young adults, with dietary fibre and vitamin C from FV clearly being implicated in this beneficial relationship.

Total Antioxidant Status in Patients with Major β-Thalassemia

OBJECTIVE

Beta-thalassemia major is an autosomal recessive disease causing severe and hemolytic anemia, which begins about 2-6 months after birth. Iron overload, which arises from recurrent transfusion and ineffective erythropoiesis, can enhance oxidative stress in thalassemic patients. The aim of this study was to evaluate the serum total antioxidant capacity of patients with ß-Thalassemia major.

METHODS

Sixty six Iranian patients with β-thalassemia major and 66 age-gender matched controls were evaluated for serum total antioxidant status (TAS), uric acid (UA), bilirubin and albumin. In addition, serum ferritin and transaminases were recorded in these subjects.

FINDINGS

Significant increases of TAS, UA, and bilirubin were observed in the patient group, compared with the control group (P<0.01). Mean TAS and bilirubin in male patients was higher than in females (P=0.005 and P=0.008, respectively). There was also direct correlation between TAS and albumin (P<0.001), bilirubin (P<0.001) and UA (P=0.002).

CONCLUSION

Endogenous antioxidants such as ferritin, UA and bilirubin can result in increased level of TAS in the patients with Beta-thalassemia major. Compensatory excess of TAS to oxidative stress could also be the reason for difference between our findings and previous studies.