Oxidized human serum albumin as a possible correlation factor for atherosclerosis in a rural Japanese population: the results of the Yakumo Study

BACKGROUND@#The effect of the redox state of human serum albumin (HSA) on the antioxidant properties of the entire body has been a focus of recent research. The usefulness of HSA redox state as a biomarker for reducing oxidative stress has been investigated in clinical settings; however, evidence for its significance as a health index in non-clinical settings is yet to be established. This study aimed to examine the associations between HSA redox state and the atherosclerotic indices of carotid intima-media thickness (IMT) and plaque formation in a rural Japanese population.@*METHODS@#We conducted a cross-sectional study as part of a health check-up program in the rural area of Hokkaido, Japan, at the end of August 2013. A total of 281 residents (124 men and 157 women) were included in the final analysis. Lifestyle-related data were obtained through a self-reported questionnaire, and ultrasound examinations were performed to measure IMT and determine plaque formation. The high-performance liquid chromatography postcolumn bromocresol green method was used to separate HSA into human nonmercaptalbumin and human mercaptalbumin (HMA).@*RESULTS@#We found a significant negative relationship between the fraction of HMA [f(HMA)] and IMT (standardized β = - 0.132, p = 0.03). Moreover, f(HMA) was significantly associated with plaque formation (p < 0.01) with an odds ratio of 0.89 (95% confidence interval, 0.81-0.97) for every 10% increment in f(HMA).@*CONCLUSIONS@#We found that the HSA redox state, as determined by f(HMA), was associated with atherosclerotic indices in Japanese subjects. These results suggest that the HSA redox state indicates the risk of developing atherosclerosis.

Relationship between dietary habits and urinary concentrations of 3-phenoxybonzoic acid in a middle-aged and elderly general population in Japan

<p><b>OBJECTIVES</b>The ingestion of pesticides in the daily diet is assumed to be the main modality of pesticide exposure for most people. A widely used class of pesticides in agricultural or residential settings is pyrethroid. We have examined the relationship between the intake frequency of selected items of vegetables and fruits and urinary metabolites of pyrethroid pesticides in a healthy general population.</p><p><b>METHODS</b>A total of 535 residents (184 men and 351 women) who attended a healthcare checkup program conducted in a rural area of Hokkaido, Japan, in August 2005 provided informed consent for their spot urine samples to be used for the determination of 3-phenoxybenzoic acid (3-PBA) levels. They also completed a self-administered questionnaire regarding the intake frequency of 12 food items. The concentrations of creatinine-corrected 3-PBA were predicted by the intake frequency of each item, using analysis-of-covariance models to adjust for age, sex, body mass index, and drinking and smoking status.</p><p><b>RESULTS</b>Both a significant association between the 3-PBA concentration and the frequency of tomato consumption and a significant positive linear trend was found in female subjects. In contrast, no such association was found in the male subjects.</p><p><b>CONCLUSIONS</b>The frequency of tomato consumption was confirmed to strongly predict the urinary pyrethroid metabolite levels in the general population-presumably because tomatoes are most often consumed raw and unpeeled (more so than all other vegetables and fruits analyzed in the current study). However, it should be noted that the 3-PBA levels, even among those subjects with the highest consumption of tomatoes, were far below the levels of toxicological significance, although the health consequences from long-term low-level exposure to pyrethroid requires further exploration.</p>

Association of serum NO( x ) level with clustering of metabolic syndrome components in middle-aged and elderly general populations in Japan

<p><b>OBJECTIVES</b>The aim of this study was to determine whether the serum nitrite plus nitrate (NO( x )) level correlates with biomarkers that are known components of the metabolic syndrome (MetS).</p><p><b>METHODS</b>Serum NO( x ) levels were measured using a commercial kit in 608 Japanese men and women between the ages of 39 and 85 years. Multivariate adjustments for age, smoking status, alcohol consumption and exercise were made in the analysis of covariance (ANCOVA). The components of the metabolic syndrome were defined based on the following criteria: body mass index (BMI) >/=25.0 kg/m(2), glycated hemoglobin (HbA1c) >/=5.6%, systolic blood pressure >/=130 mmHg or diastolic blood pressure >/=85 mmHg, high-density lipoprotein-cholesterol (HDL-C) </=1.03 mmol/l for men and </=1.29 mmol/l for women and triglyceride >/=1.69 mmol/l.</p><p><b>RESULTS</b>The logarithmically transformed age-adjusted serum NO( x ) (lnNO( x )) value was significantly higher in the low HDL-C group (1.76 +/- 0.05 mumol/l; p < 0.05) than MetS component groups (1.65 +/- 0.01 mumol/l) in men, but no difference was found in women. The means of serum lnNO( x ) after multivariate adjustment were 1.64, 1.65, 1.64, 1.66, and 1.81 mumol/l for 0, 1, 2, 3, and 4-5 MetS components for all subjects, respectively. The results of ANCOVA confirmed that the serum lnNO( x ) level was significantly correlated with the clustering of MetS components in both men and women (p < 0.0001 for trend).</p><p><b>CONCLUSION</b>Our results suggest that an increase in the clustering of MetS components was associated with the increase in serum NO levels in our general population.</p>