C-reactive protein and reactive oxygen metabolites in subjects with metabolic syndrome

Gender-specific factors associated with case complexity in middle-aged and older adults-Evidence from a large population-based study

OBJECTIVES

To investigate gender-specific factors associated with case complexity in a population-based sample of middle-aged and older adults using a holistic approach to complexity.

METHODS

Data were derived from the 8-year follow-up home visits of the ESTHER study-a German population-based study in middle-aged and older adults. Cross-sectional analyses were conducted for 2932 persons (aged 57-84). Complexity was assessed by the well-established INTERMED for the elderly interview, which uses a holistic approach to the definition of case complexity. The association between various bio-psycho-social variables and case complexity was analyzed using gender-specific logistic regression models, adjusted for sociodemographic factors (age, marital status, education).

RESULTS

Prevalence of complexity was 8.3% with significantly higher prevalence in female (10.6%) compared to male (5.8%) participants (p < 0.001). Variables associated with increased odds for complexity in both, women and men were: being divorced (odds ratio [OR] women: 1.86, 95% CI 1.05-3.30; OR men: 3.19, 1.25-8.12), higher total somatic morbidity (women: 1.08, 1.04-1.12; men: 1.06, 1.02-1.11), higher depression severity (women: 1.34, 1.28-1.40; men: 1.35, 1.27-1.44), and higher loneliness scores (women: 1.19, 1.05-1.36; men: 1.23, 1.03-1.47). Women (but not men) with obesity (Body mass index [BMI] ≥30) had higher odds (1.79, 1.11-2.89) for being complex compared to those with a BMI <25. High oxidative stress measured by derivatives of reactive oxygen metabolites in serum was associated with 2.02 (1.09-3.74) higher odds for complexity only in men.

CONCLUSIONS

This study provides epidemiological evidence on gender differences in prevalence and factors associated with case complexity in middle-aged and older adults. Moreover, this study adds to the holistic understanding of complexity by identifying novel variables linked to complexity among middle-aged and older individuals. These factors include loneliness for both genders, and high oxidative stress for men. These findings should be confirmed in future longitudinal studies.

Differential Modulation of Markers of Oxidative Stress and DNA Damage in Arterial Hypertension

Patients with arterial hypertension have an increased risk of developing tumors, particularly renal cell carcinoma. Arterial hypertension is linked to DNA damage via the generation of oxidative stress, in which an upregulated renin-angiotensin-aldosterone system plays a crucial role. The current study investigated surrogates of oxidative stress and DNA damage in a group of hypertensive patients (HypAll, n = 64) and subgroups of well (HypWell, n = 36) and poorly (HypPoor, n = 28) controlled hypertensive patients compared to healthy controls (n = 8). In addition, a longitudinal analysis was performed with some of the hypertensive patients. Markers for oxidative stress in plasma (SHp, D-ROM, and 3-nitrotyrosine) and urine (8-oxodG, 15-F2t-isoprostane, and malondialdehyde) and markers for DNA damage in lymphocytes (γ-H2AX and micronuclei) were measured. In HypAll, all markers of oxidative stress except malondialdehyde were increased compared to the controls. After adjustment for age, this association was maintained for the protein stress markers SHp and 3-nitrotyrosine. With regard to the markers for DNA damage, there was no difference between HypAll and the controls. Further, no significant differences became apparent in the levels of both oxidative stress and DNA damage between HypWell and HypPoor. Finally, a positive correlation between the development of blood pressure and oxidative stress was observed in the longitudinal study based on the changes in D-ROM and systolic blood pressure. In conclusion, we found increased oxidative stress in extensively treated hypertensive patients correlating with the level of blood-pressure control but no association with DNA damage.

Phase angle of bioimpedance as a marker of inflammation in cardiovascular diseases: A systematic review

OBJECTIVE

The aim of this systematic review was to investigate whether phase angle (PhA) of bioelectrical impedance is associated with inflammatory markers in cardiovascular diseases (CVDs).

METHODS

A search was performed in the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Latin American Caribbean Health Sciences Literature (LILACS), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science and Scopus; and in the gray literature up to January 2022. Studies with individuals with CVDs were included, to evaluate the association between PhA and the inflammatory markers interleukin (IL)-6, IL-10, IL-18, IL-1β, IL-33, tumor necrosis factor (TNF)-α, C-reactive protein (CRP), toll-like receptor (TLR) 2, TLR 4, nuclear factor κB, pathogen-associated molecular pattern molecules, lipopolysaccharides, interferon-γ-inducing factor, and JAK STAT.

RESULTS

We identified 755 articles and, after an eligibility analysis, 5 studies were included. The inflammatory markers investigated in the studies were CRP, TNF-α, and IL-33. In patients with CVDs, PhA was negatively associated with CRP and TNF-α in 80% and 100% of the studies, respectively.

CONCLUSIONS

The present results suggested that PhA is inversely associated with inflammatory markers in individuals with CVDs, and its clinical use is encouraged for better therapeutic planning.

Biomarkers of oxidative stress and reproductive complications

Oxidative stress is the result of an imbalance between the formation of reactive oxygen species (ROS) and the levels of enzymatic and non-enzymatic antioxidants. The assessment of biological redox status is performed by the use of oxidative stress biomarkers. An oxidative stress biomarker is defined as any physical structure or process or chemical compound that can be assessed in a living being (in vivo) or in solid or fluid parts thereof (in vitro), the determination of which is a reproducible and reliable indicator of oxidative stress. The use of oxidative stress biomarkers allows early identification of the risk of developing diseases associated with this process and also opens up possibilities for new treatments. At the end of the last century, interest in oxidative stress biomarkers began to grow, due to evidence of the association between the generation of free radicals and various pathologies. Up to now, a significant number of studies have been carried out to identify and apply different oxidative stress biomarkers in clinical practice. Among the most important oxidative stress biomarkers, it can be mentioned the products of oxidative modifications of lipids, proteins, nucleic acids, and uric acid as well as the measurement of the total antioxidant capacity of fluids in the human body. In this review, we aim to present recent advances and current knowledge on the main biomarkers of oxidative stress, including the discovery of new biomarkers, with emphasis on the various reproductive complications associated with variations in oxidative stress levels.

Perilla seed oil improves bone health by inhibiting bone resorption in healthy Japanese adults: A 12-month, randomized, double-blind, placebo-controlled trial

Accumulating evidence suggests the beneficial effect of omega-3 polyunsaturated fatty acids (PUFAs) on bone mineral density (BMD). However, the effects of perilla (Perilla frutescens) seed oil (PO), a rich source of α-linoleic acid (LNA), on human bone have not yet been elucidated. This randomized, double-blind, placebo-controlled trial investigated the effects of long-term PO intake on bone health in Japanese adults. After screening for eligibility, 52 participants (mean age 54.2 ± 6.4 years) were randomly assigned to placebo (n = 25) and PO (n = 27) groups, which received 7.0 ml of olive oil and PO daily, respectively. At baseline and 12-month, quantitative ultrasound of the right calcaneus was measured with an ultrasound bone densitometer and percentage of the Young Adult Mean (%YAM) was calculated. Serum levels of tartrate-resistant acid phosphatase 5b (TRACP-5b), and bone alkaline phosphatase (BALP) were evaluated. In addition, PUFA levels in the erythrocyte plasma membrane (RBC-PM), serum biological antioxidant potential (BAP), and diacron reactive oxygen metabolites (d-ROM) were evaluated. Compared with the placebo group, %YAM levels increased and serum TRACP-5b levels decreased significantly in the PO group at 12-month, while serum BALP levels remained unchanged. Moreover, RBC-PM LNA levels and BAP/d-ROM ratios increased significantly in the PO compared with the placebo group. These results suggest that long-term PO intake may improve age-related BMD decline by suppressing bone resorption and increasing LNA levels.

The Effect of Adding Job’s Tears to Yogurt on Plasma Glycated Albumin, Weight, and Lipid Profile in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Trial

Background

A potential effect of Job's tears on metabolic diseases has been recognized. However, studies on the effect of Job's tears on lipid profile and glycated albumin (GA) are still rare. This study aimed to examine the influence of Job's tears in conjunction with probiotics on the lipid profile and GA concentration of patients with type 2 diabetes mellitus.

Methods

This double-blind 12-week study involved 60 patients with type 2 diabetes assigned randomly into two groups. The first group consumed yogurt alone (containing Lactobacillus acidophilus La5 and Bifidobacterium Bb12), while the second had yogurt with Job's tears once daily (200 ml each). Lipids and GA concentrations were measured using an enzymatic colorimetric assay. Paired and unpaired Students t-test, Wilcoxon signed-rank, and Mann–Whitney test were applied. Statistical significance was set at p < 0.05.

Results

The characteristics of the groups were comparable except for baseline plasma GA (p=0.012). Subjects who used Metformin were distributed equally between the groups (p=0.118). Caloric intake between the groups also did not differ (p=0.856). There was also no change in weight, BMI, or plasma GA. Yogurt and the mixture of Job's tears and yogurt reduced cholesterol and LDL and increased HDL (all p < 0.05) within the groups. However, HDL levels in patients who had Job's tears were significantly elevated than yogurt alone (0.9 vs. 25 mg/dL, p=0.029).

Conclusion

The combination of Job's tears and yogurt improved HDL more than yogurt alone.

Post-Bariatric Hypoglycemia Is Associated with Endothelial Dysfunction and Increased Oxidative Stress

Post-bariatric hypoglycemia (PBH) is a potentially serious complication that may occur after bariatric surgery. Recurrent hypoglycemia may exert detrimental effects on vascular function. The aim of the present study was to evaluate endothelial function and oxygen reactive compounds in patients who experience PBH compared with controls. We performed a cross-sectional study on subjects with PBH (HYPO) and those without (NO-HYPO), detected by seven-day continuous glucose monitoring (CGM) performed at least twelve months after bariatric surgery. We enrolled 28 post-bariatric subjects (17.9% males, mean age 40.6 ± 10.7 years), with 18 in the HYPO group and 10 in the NO-HYPO group. In the two groups, we measured brachial artery flow-mediated dilation (FMD), oxidized low-density lipoproteins (oxLDL) and reactive oxygen metabolites (D-ROMs). The HYPO group had significantly lower FMD values than the NO-HYPO group (3.8% ± 3.0 vs. 10.5% ± 2.0, p < 0.001). A significant correlation was found between FMD and the time spent in hypoglycemia (rho = −0.648, p < 0.001), the number of hypoglycemic events (rho = −0.664, p < 0.001) and the mean glucose nadir (rho = 0.532, p = 0.004). The HYPO group showed significantly higher levels of D-ROMs (416.2 ± 88.7 UCARR vs. 305.5 ± 56.3 UCARR, p < 0.001) and oxLDLs (770.5 ± 49.7 µEq/L vs. 725.1 ± 51.6 µEq/L, p = 0.035) compared to the NO-HYPO group. In the multiple linear regression analysis, hypoglycemia independently predicted FMD values (β = −0.781, p < 0.001), D-ROMs (β = 0.548, p = 0.023) and oxLDL levels (β = 0.409, p = 0.031). PBH is associated with impaired endothelial function accompanied by increased oxidative stress.

Phase Angle: Could Be an Easy Tool to Detect Low-Grade Systemic Inflammation in Adults Affected by Prader-Willi Syndrome?

Prader-Willi syndrome (PWS) is the most common genetic inherited obesity syndrome. Obesity-related complications, mostly related to chronic low-grade systemic inflammation (LGI), are the commonest cause of mortality and morbidity in PWS adults. Phase angle (PhA) is an easy tool to screen a state of LGI in healthy subjects and in subjects with obesity and is obtained from bioelectrical impedance analysis (BIA). The aim of this study was to validate the PhA in PWS adults as a potential biomarker of LGI. In this single-center, cross-sectional study, fifteen PWS adults (six males, aged 19-41 years, and body mass index (BMI) 31.0-68.0 Kg/m2) and fifteen control subjects matched by gender, age, and BMI were evaluated. PhA values were significantly lower (p < 0.001), while high-sensitivity C-reactive protein (hs-CRP) levels were significantly higher (p < 0.001) in PWS adults compared with controls (p < 0.001), without a gender difference in the latter. After adjustment for gender, BMI, and waist circumference, significant correlation was found between PhA and hs-CRP levels (r = -0.69, p = 0.01). At the ROC analysis, the threshold value of PhA predicting the highest hs-CRP levels above the median value was found at PhA ≤ 4.8° (p = 0.01; AUC, 0.82; standard error, 0.12; 95% CI, 0.58 to 1.00). These results suggest that PWS adults had a significant higher degree of LGI compared with their counterparts. Moreover, our finding suggest that PhA is a valid biomarker of LGI also in PWS adults.

Outcomes Assessment of Sustainable and Innovatively Simple Lifestyle Modification at the Workplace - Drinking Electrolyzed-Reduced Water (OASIS-ERW): A Randomized, Double-Blind, Placebo-Controlled Trial

Oxidative stress has been associated with many diseases as well as aging. Electrolyzed-reduced water (ERW) has been suggested to reduce oxidative stress and improve antioxidant potential. This study investigated the effects of drinking ERW on biomarkers of oxidative stress and health-related indices in healthy adults. We conducted a randomized, double-blind, placebo-controlled clinical trial on 65 participants, who were allocated into two groups. Of these, 61 received intervention (32 with ERW and 29 MW [mineral water]). All participants were instructed to drink 1.5 L/day of ERW or MW for eight weeks. Biomarkers of oxidative stress and health-related indices were assessed at baseline as well as after 4 weeks and 8 weeks of intervention. Of the primary outcome variables assessed, diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential showed a significant interaction between the groups and time, with d-ROMs levels significantly decreased at 8 weeks in ERW compared to those in MW. Among the secondary outcome variables, total, visceral, and subcutaneous fat mass significantly changed over time, with a significant association observed between the groups and time. Thus, daily ERW consumption may be a potential consideration for a sustainable and innovatively simple lifestyle modification at the workplace to reduce oxidative stress, increase antioxidant potential, and decrease fat mass.

Association of Serum Markers of Oxidative Stress With Incident Major Cardiovascular Events, Cancer Incidence, and All-Cause Mortality in Type 2 Diabetes Patients: Pooled Results From Two Cohort Studies

OBJECTIVE

Oxidative stress plays an important role in the pathophysiology of type 2 diabetes mellitus (T2DM). However, associations of biomarkers of oxidative stress with diabetes complications have not yet been addressed in large cohort studies.

RESEARCH DESIGN AND METHODS

Derivatives of reactive oxygen metabolites (d-ROMs) levels, a proxy for the reactive oxygen species burden, and total thiol levels (TTLs), a proxy for the reductive capacity, were measured in 2,125 patients with T2DM from two German cohort studies of almost equal size at baseline and 3-4 years later. Multivariable adjusted Cox proportional hazards models with time-dependent modeled d-ROMs levels and TTLs were used to assess the associations with incident major cardiovascular events (MCE), cancer incidence, and all-cause mortality.

RESULTS

In total, 205, 179, and 394 MCE, cancer, and all-cause mortality cases were observed during 6-7 years of follow-up, respectively. Both oxidative stress biomarkers and the d-ROMs-to-TTL ratio were statistically significantly associated with all-cause mortality in both cohorts, and the pooled hazard ratios (HRs) and 95% CIs for top versus bottom tertiles were 2.10 (95% CI 1.43, 3.09) for d-ROMs levels, 0.59 (0.40, 0.87) for TTLs, and 2.50 (1.86, 3.36) for d-ROMs-to-TTL ratio. The d-ROMs-to-TTL ratio was also statistically significantly associated with incident MCE for top versus bottom tertile (1.65 [1.07, 2.54]), but this association did not persist after additional adjustment for chronic diseases. No associations with cancer were detected.

CONCLUSIONS

The observed strong associations of both biomarkers with mortality suggest an important contribution of an imbalanced redox system to the premature mortality of patients with diabetes.

Evaluation of oxidative stress and antioxidant capacity in healthy children

BACKGROUND

Measurement of the levels of the derivatives of reactive oxygen metabolites (d-ROMs) and of the biological antioxidant potential (BAP) enables simultaneous assessment of oxidation degree and antioxidant capacity, using the same sample and testing equipment. At present, reference values of healthy adults are clarified, but the reference value of healthy children is unknown. This study was undertaken to clarify the age-related changes and the reference values of d-ROMs and BAP in healthy children.

METHODS

The study population consisted of 77 children, ranging in age from 2 to 15 years, in normal mental and physical health as examined by a pediatrician, and seven healthy adult volunteers. Serum samples were obtained from the subjects for assay. Using these samples, d-ROMs and BAP values were measured, and the relationship with age was analyzed.

RESULTS

The d-ROMs level decreased as the age increased, while the BAP showed no correlation with the age. The d-ROMs level was significantly higher in 2-6 years group than in 7-11 years group, 12-15 years group, or healthy adults group. The BAP/d-ROMs ratio, an index of antioxidant capacity, increased significantly with higher age.

CONCLUSION

This study was carried out for the first time in healthy children in oxidative stress assessment using d-ROMs and BAP. In the infancy 2-6 years, the d-ROMs value was significantly higher and the BAP/d-ROMs ratio was significantly lower. From this, it was suggested that age should be considered when performing oxidative stress assessment using d-ROMs and BAP in children.

Association of serum markers of oxidative stress with myocardial infarction and stroke: pooled results from four large European cohort studies

Oxidative stress contributes to endothelial dysfunction and is involved in the pathogenesis of myocardial infarction (MI) and stroke. However, associations of biomarkers of oxidative stress with MI and stroke have not yet been addressed in large cohort studies. A nested case-control design was applied in four population-based cohort studies from Germany, Czech Republic, Poland and Lithuania. Derivatives of reactive oxygen metabolites (d-ROMs) levels, as a proxy for the reactive oxygen species burden, and total thiol levels (TTL), as a proxy for the reductive capacity, were measured in baseline serum samples of 476 incident MI cases and 454 incident stroke cases as well as five controls per case individually matched by study center, age and sex. Statistical analyses were conducted with multi-variable adjusted conditional logistic regression models. d-ROMs levels were associated with both MI (odds ratio (OR), 1.21 [95% confidence interval (CI) 1.05-1.40] for 100 Carr units increase) and stroke (OR, 1.17 [95% CI 1.01-1.35] for 100 Carr units increase). TTL were only associated with stroke incidence (OR, 0.79 [95% CI 0.63-0.99] for quartiles 2-4 vs. quartile 1). The observed relationships were stronger with fatal than with non-fatal endpoints; association of TTL with fatal MI was statistically significant (OR, 0.69 [95% CI 0.51-0.93] for 100 μmol/L-increase). This pooled analysis of four large population-based cohorts suggests an important contribution of an imbalanced redox system to the etiology of mainly fatal MI and stroke events.

Modulation of human osteoclastogenesis and osteoblastogenesis by lycopene

Lycopene is a lipid-soluble pigment that is mainly found in tomato. It is the carotenoid that presents the highest antioxidant potential, and due to that, it has been implicated in a decrease of the risk of several oxidative-stress-related disorders, such as cancer, inflammatory diseases and osteoporosis. Nevertheless, at the present, there is no detailed information about how lycopene affects bone metabolism. The aim of the present work was to characterize the cellular and molecular effects of lycopene on human osteoclast and osteoblast differentiation and function. It was observed that lycopene, at levels found in plasma after the ingestion of lycopene-containing products, decreased osteoclast differentiation but did not affect cell density/survival; calcium-phosphate resorbing ability was also decreased. On the other hand, osteoblast proliferation (via a decrease on apoptosis) and differentiation were increased in the presence of lycopene. The observed effects in both cell types appeared to be related to significant changes in MEK signaling pathway, but also in protein kinase C pathway in osteoclasts and NFkB signaling in osteoblasts. In conclusion, lycopene appears to promote an anabolic state of bone metabolism, stimulating osteoblastogenesis and inhibiting osteoclastogenesis, which may contribute to the promotion of a proper health status of bone tissue. This information might be relevant for the prevention and delay in the progression of osteolytic bone conditions.

Role of Ketotifen on metabolic profiles, inflammation and oxidative stress in diabetic rats

We aim to explore effects of Ketotifen on metabolic profiles, inflammation and oxidative stress. Sprague Dawley (SD) male rats were randomly divided into normal control group (NC) and experimental groups, and experimental group rats were fed with high-sugar and fat diet for 6 weeks. Then, experimental group rats were divided into diabetes group (DM) and ketotifen treatment group (KT). KT group was given ketotifen via Intragastric for 8 weeks with the dosage of 0.09 mg/kg/d. Fasting plasma glucose (FPG) was measured using glucose oxidase-phenol amino phenazone method. Fasting insulin (FINS), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were tested by enzyme-linked immunosorbent assay. Malondialdehyde (MDA) and superoxide dismutase (SOD) were quantified by spectrophotometer method. Before Ketotifen administration, compared with NC group, DM and KT groups showed significantly high levels of body weight, FPG, FINS, HOMA-IR, TC, TG, LDL, IL-6, TNF-α and MDA, and lower levels of HDL and SOD (All p <0.05). After 4 weeks of Ketotifen administration, levels of body weight, FPG, FINS, HOMA-IR, TC, TG, LDL, IL-6, TNF-α in KT group decreased significantly, and levels of HDL and SOD elevated significantly (All p <0.05). After 8 weeks of Ketotifen administration, levels of body weight, FPG, FINS, HOMA-IR, TC, TG, LDL, IL-6, TNF-α and MDA in KT group decreased more obviously, and levels of HDL and SOD elevated significantly further (All p <0.05). Ketotifen improved metabolic profiles, and ameliorated status of inflammation and oxidative stress.

Associations of self-reported smoking, cotinine levels and epigenetic smoking indicators with oxidative stress among older adults: a population-based study

Tobacco smoking and oxidative stress (OS) are both related to a wide spectrum of adverse age-related health outcomes, but their association is not yet well-established. We examined the associations of self-reported smoking indicators, serum cotinine levels and smoking-related DNA methylation biomarkers with two urinary proxy markers of OS, 8-isoprostane (8-iso) and 8-hydroxy-2'-deoxyguanosine (8-oxodG), in two independent subsets of older adults recruited in Germany (discovery set: n = 978, validation set: n = 531). We obtained DNA methylation profiles in whole blood samples by Illumina Human Methylation450K Beadchip and measured the urinary levels of both OS markers using commercial ELISA kits. After controlling for potential confounders, current smoking, cumulative smoking exposure (pack-years) and serum cotinine levels (ng/ml) were strongly associated with 8-iso levels (p values <0.0001, 0.004 and 0.001, respectively). Of 151 previously identified smoking-related CpG sites, 71 loci were associated with 8-iso levels after correction for multiple testing (FDR < 0.05) in the validation phase and were designated as loci related to 8-iso levels defined OS. In addition, serum cotinine levels, cumulative smoking exposure and a smoking index (SI) based on the 71 identified loci manifested monotonic associations with 8-iso levels. However, we did not observe any associations between these smoking indicators and 8-oxodG levels. In conclusion, this study suggests that smoking-related epigenetic alterations are closely correlated with smoking-induced OS. The identified CpG sites could potentially be prognostic epigenetic markers of OS and OS-related health outcomes. Our findings and the underlying mechanisms should be followed up in further, preferably longitudinal studies.

Molecular biomarkers of oxidative stress and role of dietary factors in gasoline station attendants

Exposure to benzene promotes oxidative stress through the production of ROS, which can damage biological structures with the formation of new metabolites which can be used as markers of oxidant/antioxidant imbalance. This study aims to assess modifications in circulating levels of advanced oxidation protein products (AOPP), advanced glycation end-products (AGE) and serum reactive oxygen metabolites (ROMs) in a group of gasoline station attendants exposed to low-dose benzene and to evaluate the influence of antioxidant food intake on these biomarkers of oxidative stress. The diet adopted by the population examined consisted of compounds belonging to the classes of terpenoids, stilbenes and flavonoids, notably resveratrol, lycopene and apigenin. Ninety one gasoline station attendants occupationally exposed to benzene and 63 unexposed male office workers were recruited for this study. Urinary trans, trans-muconic acid (t,t-MA) concentration, determined to assess individual exposure level, resulted significantly higher in exposed workers. In subjects exposed to benzene, we observed a significant increase (p < 0.001) in ROMs and AOPP levels, which were also negatively correlated with fruit and vegetables consumption. By contrast, AGE did not show a significant increase and consequently any relation with antioxidant food intake. Only ROMs, representing a global biomarker of oxidative status, resulted correlated to t,t-MA levels (p < 0.01), probably due to low-dose exposure. Increase of ROS induced by reactive benzene metabolites may promote specific biochemical pathways with a major production of AOPP, which seem to represent a more sensitive biochemical marker of oxidative stress in workers exposed to benzene compared to AGE. Furthermore, this is the first study demonstrating ROMs increment in subject exposed to benzene. These biomarkers may be useful for screening purposes in gasoline station workers and other subjects exposed to low-dose benzene. Moreover, a diet rich in fruits and vegetables demonstrated an inverse association with the levels of oxidative stress markers, suggesting a protective role of antioxidant food intake in workers exposed to oxidant agents.

Associations of metabolic, inflammatory and oxidative stress markers with total morbidity and multi-morbidity in a large cohort of older German adults

BACKGROUND

imbalances in metabolic, inflammatory and redox homeostasis play an important role in the leading theories of age-related morbidity, but no large-scale epidemiological study has been conducted so far assessing their associations with total morbidity and multi-morbidity in the same model.

METHODS

analyses were conducted in 2,547 participants of an established population-based cohort study from Germany. The participants' median age was 70 years (range: 57-84) and 51.9% were women. End points were total somatic morbidity and multi-morbidity, assessed by the Cumulative Illness Rating Scale-Geriatric version.

RESULTS

overall, 251 study participants had multi-morbidity (9.9%). Except for the redox marker 'total thiol levels of proteins', all other assessed metabolic (obesity, diabetes, dyslipidaemia and hypertension), inflammatory (C-reactive protein) and oxidative stress markers (derivatives of reactive oxygen metabolites) were significantly associated with total somatic morbidity and multi-morbidity if assessed individually. If modelled jointly, effect estimates were attenuated but remained statistically significant for the outcome 'total morbidity' and for low weight, obesity, insufficiently controlled diabetes and derivatives of reactive oxygen metabolites with respect to the outcome 'multi-morbidity'.

CONCLUSIONS

results from this large sample of older adults support hypotheses that relate imbalances in metabolic, inflammatory and redox homeostasis to age-related morbidity. Despite over adjustment for closely related metabolic, inflammatory and oxidative stress conditions in the full model, independent associations of the markers with total morbidity and/or multi-morbidity were observed. Therefore, adverse metabolic, inflammatory and oxidative stress conditions may all play important roles in the pathogenesis of age-related morbidity, which should be investigated further in future longitudinal studies.

Evidence for the free radical/oxidative stress theory of ageing from the CHANCES consortium: a meta-analysis of individual participant data

BACKGROUND

The free radical/oxidative stress theory of ageing has received considerable attention, but the evidence on the association of oxidative stress markers with mortality is sparse.

METHODS

We measured derivatives of reactive oxygen metabolite (D-ROM) levels as a proxy for the reactive oxygen species concentration and total thiol levels (TTL) as a proxy for the redox control status in 10,622 men and women (age range, 45-85 years), from population-based cohorts from Germany, Poland, Czech Republic, and Lithuania, of whom 1,702 died during follow-up.

RESULTS

Both oxidative stress markers were significantly associated with all-cause mortality independently from established risk factors (including inflammation) and from each other in all cohorts. Regarding cause-specific mortality, compared to low D-ROM levels (≤ 340 Carr U), very high D-ROM levels (>500 Carr U) were strongly associated with both cardiovascular (relative risk (RR), 5.09; 95 % CI, 2.67-9.69) and cancer mortality (RR, 4.34; 95 % CI, 2.31-8.16). TTL was only associated with CVD mortality (RR, 1.30; 95 % CI, 1.15-1.48, for one-standard-deviation-decrease). The strength of the association of TTL with CVD mortality increased with age of the participants (RR for one-standard-deviation-decrease in those aged 70-85 years was 1.65; 95 % CI, 1.22-2.24).

CONCLUSIONS

In these four population-based cohort studies from Central and Eastern Europe, the oxidative stress serum markers D-ROM and TTL were independently and strongly associated with all-cause and CVD mortality. In addition, D-ROM levels were also strongly associated with cancer mortality. This study provides epidemiological evidence supporting the free radical/oxidative stress theory of ageing and suggests that d-ROMs and TTL are useful oxidative stress markers associated with premature mortality.

Discovery of a novel epigenetic cancer marker related to the oxidative status of human blood

Long-lasting oxidative stress exposure may lead to relatively stable epigenetic modifications of the DNA in order to activate anti-oxidative defence mechanisms. Oxidative stress related DNA methylation may therefore be associated (causally or as a by-product) with cancer. We measured derivatives of reactive oxygen metabolites (D-ROM), total thiol levels (TTL) and DNA methylation with the Illumina Infinium 450K BeadChip in three samples of German individuals aged ≥50 years: n = 1,000 ESTHER study baseline participants (DNA methylation only), n = 99 ESTHER eight-year follow-up participants and n = 142 participants of the BLITZ study. The correlation coefficient of methylation at cg10342304 and D-ROM in the ESTHER 8-year follow-up sample (r = -0.427; P = 1 × 10(-5)) was replicated with a P-value indicating statistical significance after correction for multiple testing in the BLITZ sample (r = -0.192; P = 0.022). The association was robust to adjusting for potential confounders. In the ESTHER baseline sample, the hazard ratio for cancer development in 11 years of follow-up comparing bottom and top quartile of DNA methylation at cg10342304 was 1.86 (95%-confidence-interval 1.01-3.43). In summary, this first epigenome-wide screening and replication study with oxidative status markers observed a negative correlation of D-ROM levels and DNA methylation at cg10342304 in two independent cohorts. This CpG site is located in the body region of the nucleoredoxin gene. The nucleoredoxin protein is a redox-dependent inhibitor of the Wnt/ß-catenin signaling pathway, a well-characterized cancer pathway. If the observed CpG-cancer association can be successfully replicated by other studies, this epigenetic marker could be an interesting biomarker of cancer risk.

The protective effect of lycopene intake on bone loss in ovariectomized rats

Antioxidant lycopene supplementation has been shown to decrease oxidative stress and have beneficial effects on bone health. However, it remains unclear whether lycopene exerts its beneficial effect on bone metabolism through mitigation of oxidative stress in vivo. The aim of this study was to investigate whether lycopene intake protects against bone loss by reducing oxidative stress in ovariectomized rats. Female Sprague-Dawley 6-week-old rats were ovariectomized and randomly divided into four groups according to the lycopene content of their diet: 0, 50, 100, and 200 ppm. The tibial bone mineral density (BMD) in the 50, 100, and 200 ppm groups was significantly higher than that in the 0 ppm group. Serum and urinary bone resorption marker levels were significantly lower in the 50, 100, and 200 ppm groups than in the 0 ppm group. There was no significant difference in systemic oxidative stress markers among all groups. However, systemic oxidative stress levels were inversely correlated with the tibial BMD. Our findings suggest that lycopene intake significantly inhibits bone loss by suppressing bone resorption in ovariectomized rats. Further studies are necessary to clarify the effect of lycopene on oxidative stress in local tissues such as bone tissue.

Association between Oxidative Stress and Frailty in an Elderly German Population: Results from the ESTHER Cohort Study

BACKGROUND

Oxidative stress (OS) and inflammatory biomarkers have been postulated to be important factors in the development of age-related diseases. While causes of frailty are complex and multidimensional based on the interaction of genetic, biological, physical, and environmental factors, the biological basis of frailty has been difficult to establish.

OBJECTIVE

In this study, we aimed to assess the possible association between different OS and inflammatory biomarkers and frailty.

METHODS

This cross-sectional analysis was performed among 2,518 subjects participating in a large population-based cohort study on aging conducted in Germany. Frailty was assessed as proposed by Fried et al. [J Gerontol A Biol Sci Med Sci 2001;56:M146-M156]. OS biomarkers, biological antioxidant potential (BAP), derivate of reactive oxygen metabolites (d-ROM) and total thiol levels (TTL), and an established biomarker of inflammation C-reactive protein (CRP) were measured by spectrophotometry and immunoturbidimetry. Logistic regression models were performed to assess the relationship between the OS biomarkers and frailty status. Odds ratios (OR) and 95% confidence intervals (CI) were calculated to quantify the associations.

RESULTS

Mean levels of d-ROM, TTL, and CRP differed between frail and non-frail participants (p values <0.0001). Comparing highest and lowest quartiles of the biomarkers, statistically significant positive associations with frailty were observed for d-ROM (OR: 2.02, 95% CI: 1.25-3.25) and CRP (OR: 3.15, 95% CI: 2.00-4.96), respectively, after controlling for age and sex. An inverse statistically significant association with frailty was observed for TTL (OR: 0.42, 95% CI: 0.25-0.69).

CONCLUSION

The strong associations with OS biomarkers and CRP support a major role of OS and inflammation in the development of frailty, which should be followed up in further longitudinal studies on frailty.

Lycopene intake facilitates the increase of bone mineral density in growing female rats

Intake of the antioxidant lycopene has been reported to decrease oxidative stress and have beneficial effects on bone health. However, few in vivo studies have addressed these beneficial effects in growing female rodents or young women. The aim of this study was to investigate the effect of lycopene intake on bone metabolism through circulating oxidative stress in growing female rats. Six-week-old Sprague-Dawley female rats were randomly divided into 3 groups according to the lycopene content in their diet: 0, 50, and 100 ppm. The bone mineral density (BMD) of the lumbar spine and the tibial proximal metaphysis increased with lycopene content in a dose-dependent manner; the BMD in 100 ppm group was significantly higher than in the 0 ppm group. The urine deoxypyridinoline concentrations were significantly lower in the 50 and 100 ppm groups than in the 0 ppm group, and the serum bone-type alkaline phosphatase activity was significantly higher in 100 ppm group than in the 0 ppm group. No difference in systemic oxidative stress level was observed; however, the oxidative stress level inversely correlated with the tibial BMD. Our findings suggested that lycopene intake facilitates bone formation and inhibits bone resorption, leading to an increase of BMD in growing female rats.

The impact of match-play tennis in a hot environment on indirect markers of oxidative stress and antioxidant status

Objectives

The purpose of this study was to determine the impact of changes in oxidative stress and antioxidant status in response to playing tennis in HOT (∼36°C and 35% relative humidity (RH)) and COOL (∼22°C and 70% RH) conditions.

Methods

10 male tennis players undertook two matches for an effective playing time (ie, ball in play) of 20 min, corresponding to ∼122 and ∼107 min of total play in HOT and COOL conditions, respectively. Core body temperature, body mass and indirect markers of oxidative stress (diacrons reactive oxygen metabolic test) and antioxidant status (biological antioxidant potential test) were assessed immediately prematch, midmatch and postmatch, and 24 and 48 h into recovery.

Results

Regardless of the condition, oxidative stress remained similar throughout play and into recovery. Likewise, match-play tennis in the COOL had no impact on antioxidant status. However, antioxidants status increased significantly in the HOT compared with COOL environment (p<0.05). Body mass losses (∼0.5 kg) were similar between conditions. Rectal temperature increased during both matches (p<0.05), but with a greater magnitude in the HOT (39.3±0.5°C) versus COOL (38.7±0.2°C) environment (p<0.05).

Conclusions

Match-play tennis in the heat does not exacerbate the development of oxidative stress, but significantly increases antioxidant status. These data suggest that the heat stress observed in the HOT environment may provide a necessary signal for the upregulation of antioxidant defence, dampening cellular damage.

Oxidative stress markers and all-cause mortality at older age: a population-based cohort study

BACKGROUND

The free radical/oxidative stress theory of aging has recently received much attention but the association of oxidative stress markers with all-cause mortality was not yet assessed in humans.

METHODS

We measured derivatives of reactive oxygen metabolites (d-ROM) as a proxy for the reactive oxygen species concentration and total thiol levels (TTL) as a proxy for the redox control status in 2,932 participants of a population-based cohort study from Germany.

RESULTS

The median age of the population was 70 years and 120 (4.1%) study participants died during a mean follow-up of 3.3 years. Compared with the bottom tertiles, the top tertiles of d-ROM and TTL concentrations were both associated with all-cause mortality in models adjusted for age, sex, education, smoking, physical activity, and alcohol consumption (hazard ratios and 95% confidence intervals: 1.63 [1.01; 2.63] and 0.68 [0.53; 0.87], respectively). Adding diseases, the inflammatory marker C-reactive protein or a cumulative somatic morbidity index did not alter the results for TTL. However, the association of d-ROM and mortality was attenuated and no longer statistically significant after adding C-reactive protein and the somatic morbidity index to the model.

CONCLUSIONS

This study adds epidemiological evidence to the free radical/oxidative stress theory of aging. Both d-ROM and TTL were associated with mortality at older age. For TTL, this association was independent of baseline health status. Inflammation and higher general morbidity could be intermediate states on the pathway from high d-ROM levels to mortality. This hypothesis should to be explored by future studies with repeated measurements.

Effect of dietary prebiotic supplementation on advanced glycation, insulin resistance and inflammatory biomarkers in adults with pre-diabetes: a study protocol for a double-blind placebo-controlled randomised crossover clinical trial

BACKGROUND

Advanced glycation endproducts (AGEs) contribute to the development of vascular complications of diabetes and have been recently implicated in the pathogenesis of diabetes. Since AGEs are generated within foodstuffs upon food processing, it is increasingly recognised that the modern diet is replete with AGEs. AGEs are thought to stimulate chronic low-grade inflammation and promote oxidative stress and have been linked to the development of insulin resistance. Simple therapeutic strategies targeted at attenuating the progression of chronic low-grade inflammation and insulin resistance are urgently required to prevent or slow the development of type 2 diabetes in susceptible individuals. Dietary modulation of the human colonic microbiota has been shown to confer a number of health benefits to the host, but its effect on advanced glycation is unknown. The aim of this article is to describe the methodology of a double-blind placebo-controlled randomised crossover trial designed to determine the effect of 12 week consumption of a prebiotic dietary supplement on the advanced glycation pathway, insulin sensitivity and chronic low-grade inflammation in adults with pre-diabetes.

METHODS/DESIGN

Thirty adults with pre-diabetes (Impaired Glucose Tolerance or Impaired Fasting Glucose) aged between 40-60 years will be randomly assigned to receive either 10 grams of prebiotic (inulin/oligofructose) daily or 10 grams placebo (maltodextrin) daily for 12 weeks. After a 2-week washout period, study subjects will crossover to receive the alternative dietary treatment for 12 weeks. The primary outcome is the difference in markers of the advanced glycation pathway carboxymethyllysine (CML) and methylglyoxal (MG) between experimental and control treatments. Secondary outcomes include HbA1c, insulin sensitivity, lipid levels, blood pressure, serum glutathione, adiponectin, IL-6, E-selectin, myeloperoxidase, C-reactive protein, Toll-like Receptor 4 (TLR4), soluble receptor for AGE (sRAGE), urinary 8-isoprostanes, faecal bacterial composition and short chain fatty acid profile. Anthropometric measures including BMI and waist circumference will be collected in addition to comprehensive dietary and lifestyle data.

DISCUSSION

Prebiotics which selectively stimulate the growth of beneficial bacteria in the human colon might offer protection against AGE-related pathology in people at risk of developing type 2 diabetes.

TRIAL REGISTRATION

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12613000130763.

Zinc, iron and vitamins A, C and e are associated with obesity, inflammation, lipid profile and insulin resistance in Mexican school-aged children

The objective of this cross-sectional study was to evaluate the relationship between micronutrient status and obesity, lipids, insulin resistance and chronic inflammation in children. Weight, height, waist circumference and body composition (dual-energy X-ray absorptiometry (DEXA)) were determined in 197 school-aged children. Lipids, glucose, insulin, C-reactive protein (CRP), zinc, iron and vitamins A, C and E were analyzed in blood. Vitamin C and vitamin E:lipids were negatively associated with Body Mass Index (BMI), waist-to-height ratio (WHR) and body and abdominal fat (p < 0.05). Vitamin A was positively associated with BMI, BMI-for-age, WHR and abdominal fat (p < 0.05). Iron and vitamin E:lipids were negatively associated with insulin (p < 0.05). Vitamins A, C and E and iron were negatively associated with CRP (p < 0.05). Interaction analysis showed that children who were overweight and obese who also had low concentrations of vitamin A had higher CRP and lower triglycerides (p < 0.1), children with low vitamin E had significantly lower glucose and triglycerides (p < 0.1) and higher low-density lipoprotein (LDL) concentrations (p < 0.05), and children with low zinc concentrations had higher insulin resistance compared with children with adequate weight (p < 0.05). In conclusion, low vitamin C concentration and vitamin E:lipids were associated with obesity. Furthermore, low concentrations of zinc, vitamins A and E in children who were overweight and obese were associated with lipids, inflammation and insulin resistance.