Yongye Sun

Vitamin E supplementation protects erythrocyte membranes from oxidative stress in healthy Chinese middle-aged and elderly people

Elderly people are subject to higher levels of oxidative stress than are young people. Vitamin E, as a powerful antioxidant residing mainly in biomembranes, may provide effective protection against oxidative membrane damage and resultant age-related deterioration, especially in the elderly. We hypothesized that appropriate levels of vitamin E supplementation would protect erythrocyte membranes from oxidative stress and thus improve membrane fluidity in healthy middle-aged and elderly people. To test this, we conducted a 4-month double-blind, randomized trial in which 180 healthy subjects (55-70 years old) were randomly divided into 4 groups: group C (control), and 3 treatment groups in which daily doses of 100 mg (VE1), 200 mg (VE2), and 300 mg (VE3) dl-α-tocopheryl acetate were administered. We measured plasma α-tocopherol concentration, malondialdehyde, and superoxide dismutase levels, erythrocyte hemolysis, and erythrocyte membrane fluidity at the beginning and end of the trial. After 4 months supplementation, plasma α-tocopherol concentrations in the 3 treatment groups had increased by 71%, 78%, and 95%, respectively (all P < .01), and significant decreases in plasma malondialdehyde concentrations were observed in these groups (all P < .05). Erythrocyte hemolysis was decreased by 20% to 38% after vitamin E supplementation (all P < .05), and in addition, groups VE2 and VE3 showed dramatic improvements in erythrocyte membrane fluidity (P < .01). Surprisingly, superoxide dismutase activity also decreased significantly in the treatment groups (all P < .05). In summary, vitamin E supplementation apparently alleviates oxidative stress in healthy middle-aged to elderly people, at least in part by improving erythrocyte membrane fluidity and reducing erythrocyte hemolysis.

Anemia Prevalence among Pregnant Women and Birth Weight in Five Areas in China

Objectives: To investigate the current prevalence of anemia among pregnant women in different areas of China and the association with birth weight and educational level. Methods: A total of 6,413 women aged 24–37 in the third trimester of pregnancy from five areas were randomly selected from all gravidas who gave birth in the hospitals from 1999 to 2003. Blood hemoglobin concentration (Hb) was measured by the cyanomethemoglobin method; Hb <110 g/l was considered as anemia. Results: The overall prevalence of anemia was 58.6%, ranging from 48.1 to 70.5% in the five areas. There was a significant difference in the prevalence of anemia between women who have mental jobs and those who have physical jobs (52.3 vs. 61.1%, p < 0.01). The prevalence of anemia depended on the level of education: with 52.9, 62.4 and 66.5%, for college, secondary school and primary education, respectively, and the difference was statistically significant (p = 0.005). Results showed that higher birth weight was associated with Hb concentrations ranging from 90 to 140 g/l, whereas lower birth weight occurred below 80 g/l and above 140 g/l Hb. Conclusions: The prevalence of anemia in Chinese pregnant women was high both in rural areas and towns. Area of residence, education level and type of job influenced the prevalence of anemia. Low maternal Hb concentrations influenced birth weight.

Effects of vitamin E on plasma lipid status and oxidative stress in Chinese women with metabolic syndrome.

Following the change of dietary structure and living style, metabolic syndrome (MetS) has become increasingly common in China, especially in women, who have abnormal plasma lipid profiles with increased levels of oxidative stress. Vitamin E (VitE) is a powerful chain-breaking antioxidant, which may be a protective factor against oxidative stress-related diseases. This study investigated the effects of three different dosages of tocopherol supplementation (100 IU /day, 200 IU /day, 300 IU /day) for 4 months in Chinese women with MetS. The plasma VitE concentrations increased significantly after the 4 months of supplementation (p < 0.01). The protective decreases in plasma total cholesterol were significant in 200 IU/day and 300 IU/day VitE groups (p < 0.05), but decreases in high-density lipoprotein cholesterol were also significant in all the supplementation groups (p < 0.05). Plasma triglycerides were unaltered (p > 0.05). The indicators of oxidative stress decreased substantially in all of the VitE supplementation groups: malondialdehyde (MDA) was reduced by nearly 50 percent (all groups, p < 0.001), erythrocyte hemolysis was decreased by nearly 40 percent (all groups, p < 0.05); among which the 300IU/day VitE group showed the most significant effect. However, the activity of superoxide dismutase (SOD) decreased after the trial (p < 0.001). VitE provided marked benefits in reducing oxidative stress levels and improving lipid status in women with MetS. Although no dose-effect relationship was observed, 300 IU VitE per day showed the optimal effect. Research is needed to identify potential protective mechanisms or utilization of vitamin E during MetS.

Screening and intervention of diabetes mellitus in patients with pulmonary tuberculosis in poverty zones in China: rationale and study design.

BACKGROUND The merging epidemics of pulmonary tuberculosis (PTB) and diabetes mellitus (DM) have been raised concerns by many experts but no large scale screening and intervention have been launched yet, especially in low-income areas. The current study aims to understand the prevalence of DM in active PTB patients and evaluate the outcomes of diet and living habit intervention in poverty zones in China. METHODS/DESIGN A cross-sectional investigation and intervention study will be carried out. At least 7000 active PTB patients will be recruited, together with 7000 nonTB persons from the same community. The project will be divided into two stages. The first stage is to train TB workers on DM screening and regular treatment. Screening and related investigation will be carried out afterwards. The second stage is focussed on intervention. A comprehensive strategy will be utilized to conduct health promotion among the patients, the health providers and the lay public. DISCUSSION To our knowledge, this is the first and largest study which focuses on the prevalence of DM in PTB in China. We hypothesize that the current prevalence of DM in PTB in China will be understood and the results of our study will provide important evidence for preventing and controlling DM and PTB.

Association between Sarcopenia and Metabolic Syndrome in Middle-Aged and Older Non-Obese Adults: A Systematic Review and Meta-Analysis

The associations between sarcopenia and metabolic syndrome (MetS) in non-obese middle-aged and older adults remain controversial. Thus, this meta-analysis aimed to evaluate the overall prevalence of MetS and the correlations between sarcopenia and MetS in middle-aged and older non-obese adults. We performed a systematic searched strategy using PUBMED, EMBASE and Web of Science databases for relevant observational studies investigating sarcopenia and MetS up to 11 May 2017. The polled prevalence of MetS and odds ratios with 95% confidence intervals (CI), as well as subgroup analyses were calculated using a random effects model. Twelve articles with a total of 35,581 participants were included. The overall prevalence of MetS was 36.45% (95% CI, 28.28–45.48%) in middle-aged and older non-obese adults with sarcopenia. Our analysis demonstrated a positive association between sarcopenia and MetS (OR = 2.01, 95% CI, 1.63–2.47). The subgroup analysis showed that both larger cohort size and the use of dual-energy X-ray absorptiometry to measure body composition can enhance the relationship. Our study revealed that a higher proportion of MetS in middle-aged and older non-obese people with sarcopenia. Moreover, sarcopenia was positively associated with MetS in this population. Further large-scale prospective cohort studies are needed to investigate the causality between sarcopenia and MetS.

Enhancement of vitamin A combined vitamin D supplementation on immune response to Bacille Calmette-Guérin vaccine revaccinated in Chinese infants

OBJECTIVE To investigate whether there is an association between diameter of bacille Calmette-Guérin (BCG) scars and effect of purified protein derivative (PPD) reaction and to determine whether vitamin A (VA) combined vitamin D (VD) supplementation influences the immune response to BCG revaccinated in Chinese infants. METHODS A cross-section and 3-month community-randomised trial was conducted. A total of 5 629 infants at 3, 6 and 12 months of age in Junan County of China were examined for BCG scar formation. Then, 597 revaccinated infants were randomly assigned to supplementation (n=307) and control (n=290) groups. The supplementation group were daily assigned to 1 500 IU VA and 500 IU VD for 3 months. Then all infants were subjected to skin test with PPD. RESULTS The diameter of BCG scars was positively correlated with diameter of skin indurations of PPD (r=0.17, P<0.05) in the 5 629 infants. The rate of positive response to PPD was higher in the supplementation group than in the control group (96.1% versus 89.7%, P<0.05, prevalence ratio 1.07, 95% CI 1.02-1.12). The prevalence ratio of PPD response for the supplementation group compared with that for the control group was 1.07 (95% CI 1.01-1.13) for the males and 1.08 (95% CI 1.00-1.17) for the females. For the supplementation group, the males got larger tuberculin induration than the females [(0.73±0.21) cm versus (0.67±0.20) cm, P<0.05) after intervention. CONCLUSIONS The diameter of BCG scars was effectively correlated with PPD response, which indicates BCG scar formation may be an useful tool to evaluate the effect of tuberculosis prevention. VA combined VD supplementation may play an immuno-regulatory role in BCG revaccination. This may contribute to the prevention of childhood tuberculosis.

Antioxidant micronutrient supplementation increases erythrocyte membrane fluidity in adults from a rural Chinese community

The objective of the present study was to investigate age-related differences in erythrocyte membrane fluidity (EMF) and changes in antioxidant capacity following supplementation. A total of seventy-four children were randomly divided into two groups: group A1 was the placebo-controlled group and group A2 was supplemented daily with 600 μg retinol, 1·0 mg β-carotene, 100 mg tocopherol, 300 mg ascorbic acid and 200 μg Se. A total of ninety young people were randomly divided into B1 and B2 groups, and ninety-one elderly subjects were divided into C1 and C2 groups. Groups B1 and C1 were placebo-controlled groups, and groups B2 and C2 were daily supplemented with 900 μg retinol, 1·5 mg β-carotene, 200 mg tocopherol, 500 mg ascorbic acid and 400 μg Se. Results showed that plasma malondialdehyde (MDA) was 5·35 μmol/l in children, which was lower than in young and elderly people. The MDA levels of the young and elderly individuals in the treated groups were significantly lower compared with the control groups, but the supplementation did not alter MDA levels in children. At baseline, there was a lower value of polarisation (ρ) and microviscosity (η) in children, indicating a higher EMF, than in both the young and elderly subjects. After the 2-month trial, the ρ and η values of young and elderly subjects in the treated groups decreased significantly in comparison with the placebo groups, indicating an increase in EMF. In conclusion, there was a background of higher MDA levels and lower EMF in young and elderly people than in children, which could be improved by antioxidant supplementation.

The association between obesity and restless legs syndrome: A systemic review and meta-analysis of observational studies

OBJECTIVE Restless legs syndrome (RLS) has been reported to occur more frequently in obese individuals than in those with normal weight. In this study, a systematic review and meta-analysis was performed to explore the relationship between obesity and RLS. METHODS Published articles were identified through a comprehensive review of PUBMED and EMBASE from inception to the 16th December 2017. Data from studies reporting relative risks, odds ratios, or hazard ratios comparing the risk of RLS among individuals with obesity versus people with normal weight were analyzed. A random-effect model was used to calculate pooled odds ratios and 95% confident intervals (CI) for the association between obesity and RLS. RESULTS Findings for a total of 197,204 participants were pooled across 15 studies and were examined. Our analyses demonstrated a positive association between obesity and RLS, with an odds ratio (OR) of 1.44 (95%CI: 1.31-1.58, I2 = 62.3%). Overweight subjects were also likely to have RLS, with an odds ratio of 1.29 (95%CI: 1.22-1.36, I2 = 0). In subgroup analysis, women (OR = 1.42) with obesity were more likely to have RLS as compared with men (OR = 1.19). CONCLUSIONS Adults with obesity are more likely to suffer from RLS, with women at higher risk.