Yusong Ding

Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis

Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (p< 0.000001) following arsenic exposure: inorganic arsenic (iAs), monomethyl arsenic (MMA), dimethyl arsenic (DMA), and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD): 1.00; 95% confidence interval (CI): 0.60–1.40; p< 0.00001) and MMA (SMD: 0.49; 95% CI: 0.21–0.77; p = 0.0006) also increase, while the percentage of DMA (SMD: −0.57; 95% CI: −0.80–−0.31; p< 0.0001), primary methylation index (SMD: −0.57; 95% CI: −0.94–−0.20; p = 0.002), and secondary methylation index (SMD: −0.27; 95% CI: −0.46–−0.90; p = 0.004) decrease. Smoking, drinking, and older age can reduce arsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

Ethnic Differences in Prevalence of General Obesity and Abdominal Obesity among Low-Income Rural Kazakh and Uyghur Adults in Far Western China and Implications in Preventive Public Health

Background The global pandemic of obesity has become a disastrous public health issue that needs urgent attention. Previous studies have concentrated in high-income urban settings and few cover low-income rural settings especially nomadic residents in mountain areas. This study focused on low-income rural and nomadic minority people residing in China’s far west and investigated their prevalence and ethnic differences of obesity. Methods A questionnaire-based survey and physical examination of 8,036 individuals were conducted during 2009–2010, using stratified cluster random sampling method in nomadic Kazakhs and rural Uyghur residents (≥18 years old) in 18 villages, Xinjiang, China, about 4,407 km away from capital Beijing. Obesity was defined by BMI and WC. Results The overall prevalence of general and abdominal obesity in Kazakh adults were 18.3% and 60.0%, respectively and in Uyghur, 7.6% and 54.5%, respectively. Female’s prevalence of obesity was higher than male’s for general obesity (45–54 age group in Uyghur, P = 0.041) and abdominal obesity (≥55 years in Kazakhs, P55∼ = 0.010, P65∼ = 0.001; and ≥18 years in Uyghurs, P<0.001). Kazakh’s prevalence of obesity was higher than Uyghur’s (general obesity: ≥35 years, P<0.001; abdominal obesity: ≥25 years in males and ≥65 years in females, P<0.01). The prevalence of obesity increased after 18 years old and subsequently decreased after 55 years old. Meat consumption, older age, and female gender had a higher risk of obesity in these two minorities. Conclusions Both general and abdominal obesity were common in rural ethnic Kazakhs and Uyghurs. The prevalence rates were different in these two minorities depending on ethnicity, gender, and age. Kazakhs, females and elderly people may be prioritized in prevention of obesity in western China. Because of cost-effectiveness in measuring BMI and WC, we recommend that BMI and WC be integrated into local preventive policies in public health toward screening obesity and related diseases in low-income rural minorities.

Lutein Has a Protective Effect on Hepatotoxicity Induced by Arsenic via Nrf2 Signaling

Arsenic produces liver disease through the oxidative stress. While lutein can alleviate cytotoxic and oxidative injury, nuclear factor erythroid 2-related factor 2 (Nrf2) pathway plays a critical role in defending oxidative species. However, the mechanisms by which lutein protects the liver against the effect of arsenic are not known. Therefore, this study aims to investigate the mechanisms involved in the action of lutein using mice model in which hepatotoxicity was induced by arsenic. We found that mice treatment with lutein could reverse changes in morphological and liver indexes and result in a significant improvement in hepatic function comparing with arsenic trioxide group. Lutein treatment improved the activities of antioxidant enzymes and attenuated increasing of ROS and MDA induced by arsenic trioxide. Lutein could increase the mRNA and protein expression of Nrf2 signaling related genes (Nrf2, Nqo1, Ho-1, and Gst). These findings provide additional evidence that lutein may be useful for reducing reproductive injury associated with oxidative stress by the activation of Nrf2 signaling. Our findings suggest a possible mechanism of antioxidant lutein in preventing the hepatotoxicity, which implicate that a dietary lutein may be a potential treatment for liver diseases, especially for arsenicosis therapy.

Efficacy of Procyanidins against In Vivo Cellular Oxidative Damage: A Systematic Review and Meta-Analysis.

Aims In this study, the efficacy of proanthocyanidins (PCs) against oxidative damage was systematically reviewed to facilitate their use in various applications. Methods A meta-analysis was performed by two researchers. Each investigator independently searched electronic databases, including Cochrane, PubMed, Springer, Web of Science, China National Knowledge Infrastructure (CKNI), China Science and Technology Journal Database (CSTJ), and WanFang Data, and analyzed published data from 29 studies on the effects of PCs against oxidative damage. Oxidative stress indexes included superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), and total antioxidative capacity (T-AOC). Results Compared with the oxidative damage model group, PCs effectively improved the T-AOC, SOD, GSH, GPx, and CAT levels, and reduced the MDA levels; these differences were statistically significant (P < 0.05). In studies that used the gavage method, SOD (95% CI, 2.33–4.00) and GPx (95% CI, 2.10–4.05) were 3.16-fold and 3.08-fold higher in the PC group than in the control group, respectively. In studies that used the feeding method, SOD (95% CI, 0.32–1.74) and GPx (95% CI, -0.31 to 1.65) were 1.03-fold and 0.67-fold higher in the PC group than in the control group, respectively. Statistically significant differences in the effects of PCs (P < 0.00001) were observed between these two methods. MDA estimated from tissue samples (95% CI, -5.82 to -2.60) was 4.32-fold lower in the PC group than in the control group. In contrast, MDA estimated using serum samples (95% CI, -4.07 to -2.06) was 3.06-fold lower in the PC group than in the control group. The effect of PCs on MDA was significantly greater in tissue samples than in serum samples (P = 0.02). Conclusion PCs effectively antagonize oxidative damage and enhance antioxidant capacity. The antagonistic effect may be related to intervention time, intervention method, and the source from which the indexes are estimated.

Prevalence of Diabetes Mellitus and Impaired Fasting Glucose, Associated with Risk Factors in Rural Kazakh Adults in Xinjiang, China

Objective: This study aimed to estimate the prevalence of diabetes mellitus (DM) and impaired fasting glucose (IFG) in a Kazakh population aged ≥18 years living in the YiLi District of Xinjiang, China and to evaluate the associated risk factors of diabetes. Methods: Randomly selected adults, living for at least 6 months in the YiLi District in Xinjiang had their clinical characteristics and standard blood chemistries measured. DM and IFG were defined according to WHO 1999 criteria. The adjusted odds ratio (ORs) and 95% confidence intervals were calculated for the association of diabetes risk factors in multivariate logistic regression models. Results: A total of 3919 subjects were randomly selected. The age-and gender-standardized prevalence of DM and IFG were 5.9% and 10.0%, respectively. The prevalence of DM and IFG increased with age and BMI. Prevalence of 7.4%, 12.2% in males and 4.9%, 8.6% in females for DM and IFG. Compared by sex, prevalence of DM and IFG was higher in males. Prevalence of 3.4%, 8.1% in normal, 6.7%, 11.9% in overweight and 12.0%, 13.0% in obesity for diabetes and IFG. In the multivariable logistic models, male sex, older age, unmarried, overweight, obesity, hypertension, triglycerides and smoking were all significantly associated with an increased risk of diabetes. Conclusions: The prevalence of DM and IFG among minorities was lower than the overall national level both in men and women (9.7% in total, 10.6% in males, 8.8% in females), and also lower than among the Han ethnicity (9.26%) which predominates in China today.

Lutein alleviates arsenic-induced reproductive toxicity in male mice via Nrf2 signaling.

This study aims to investigate the mechanisms involved in the action of lutein (LU) alleviating arsenic-induced reproductive toxicity using mice model. Forty male Kunming mice were received following treatments by gavage: normal saline solution (control), arsenic trioxide (ATO; 5 mg/kg/day), LU (40 mg/kg/day), and ATO + LU (5 mg/kg/day + 40 mg/kg/day). At the end, the mice were killed by cervical dislocation and weighed. Pathological examination was done on the testis. The biomedical parameters including superoxide dismutase (SOD), glutathione (GSH), total antioxidative capability, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and reproductive indexes were analyzed. The messenger RNA (mRNA) and protein expression of Nrf2, heme oxygenase 1 (HO-1), glutathione S-transferase (GST), nicotinamide adenine dinucleotide phosphate dehydrogenase, quinone 1 (NQO1) in testis were detected by real-time polymerase chain reaction and Western blot. We found that there was a decrease in sperm count; testis somatic index; the activities of SOD, GSH, total antioxidative capacity (p < 0.01, respectively) in ATO-treated mice, while there was an increase in the levels of sperm abnormalities, MDA, and 8-OHdG than control (p < 0.01, respectively). The groups treated with ATO + LU showed recovery of the measured parameters between those of ATO or saline-treated group. The antagonized interaction between ATO and LU was statistically significant (p < 0.01). Mice treated with ATO + LU also showed greater mRNA expression of Nrf2, HO-1, NQO1, and GST than ATO or saline-treated groups. These findings suggest that LU alleviates reproductive toxicity induced by arsenic in male mice via Nrf2 signaling, which implicates a possible mechanism of LU in preventing the reproductive injury, and elucidates that consuming the rich plant sources of LU will alleviate the reproductive toxicity induced by chemicals.

Association of homeostasis model assessment of insulin resistance, adiponectin, and low-grade inflammation with the course of the metabolic syndrome.

OBJECTIVE We examined the association between insulin resistance (IR), adiponectin, and inflammation markers and the development of metabolic syndrome (MetS). Furthermore, we aimed to establish the relationship between IR, serum adiponectin, and parameters of chronic inflammation. METHODS MetS was assessed in 1628 Kazakh participants (768 men; 860 women) in Xinjiang, Northwestern China. RESULTS Adiponectin, homeostasis model assessment of IR (HOMA-IR), interleukin-6 (IL-6), and C-reactive protein (CRP) remained significantly associated with MetS after further adjustment for sex, age, smoking status, low-density lipoprotein cholesterol, total cholesterol, and high-density lipoprotein cholesterol. Moreover, HOMA-IR, IL-6, and CRP increased concurrently with an increased number of MetS components, and an inverse trend between adiponectin and increased number of MetS components was found. The median of IL-6 and CRP increased with HOMA-IR from the lowest to the highest quartile. In contrast, the median of adiponectin remarkably decreased with HOMA-IR from the lowest to the highest quartile (P<0.001). According to multiple linear regression analysis, adiponectin, CRP, and IL-6 also showed a significant association with HOMA-IR. CONCLUSION We strengthen the notion that HOMA-IR, adiponectin, and inflammatory markers can predict the course of MetS. Furthermore, our results suggest that a chronic state of inflammation and decreased serum adiponectin might be associated with IR.

Prevalence of Hypertension among Adults in Remote Rural Areas of Xinjiang, China

Objective: The present study aimed to estimate prevalence of hypertension among adults in rural remote areas of Xinjiang, China and evaluate the associated factors of hypertension. Methods: The survey was based on questionnaire interviews and clinical measurements of 11,340 individuals (≥18 years old), and was conducted during 2009–2010 via a stratified cluster random sampling method in the remote rural areas of Xinjiang, about 4407 km away from the capital Beijing. Hypertension was defined according to WHO/ISH criteria. Results: Systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the population were (126.3 ± 21.4) and (80.9 ± 13.4) mmHg. Compared with Han nationality subjects, SBP and DBP of Kazakh nationality subjects were significantly high (p < 0.05), while the SBP and DBP of Uyghur subjects were significantly low (Kazakh: (128.7 ± 23.9) and (83.0 ± 14.6) mmHg, Uyghur: (123.6 ± 19.3) and (77.4 ± 12.7) mmHg, Han: (126.5 ± 20.5) and (82.6 ± 11.9) mmHg, p < 0.05). Prevalence of hypertension of the population was 32.1%, and was greater among Kazakhs and lower among Uyghur than Han (Kazakh: 36.9%, Uyghur: 26.1%, Han: 33.7%, p < 0.05). The age-standardized prevalence of hypertension was 30.2%, and was greater among Kazakhs while lower among Uyghurs than Han subjects (Kazakh: 37.0%, Uyghur: 26.0%, Han: 33.8%, p < 0.05, p < 0.05). Multivariate logistic regression analyses showed Gender (OR = 1.324), age (OR = 2.098, 3.681, 6.794, 9.473, 14.646), nationality (OR = 1.541), occupation (OR = 1.659, 1.576), education (OR = 1.260), BMI (OR = 1.842), WC (OR = 1.585), WHR (OR = 1.188), WHR (OR = 1.188), diabetes (OR = 1.879), hypertriglyceridemia (OR = 1.361), hypercholesterolemia (OR = 1.131) and high blood low density lipoprotein cholesterol (LDL-C) (OR = 1.956) were all positively correlated with hypertension, while low blood high density lipoprotein cholesterol (HDL-C) (OR = 0.765) was negatively correlated with hypertension. Conclusions: Prevalence of hypertension among adults in remote rural areas of Xinjiang was higher than the national average. Prevalence of hypertension was greater among Kazakhs and lower among Uyghurs than Han nationals, thus indicating significant differences between regions and nationalities. Gender, age, nation, occupation, education, overweight or obesity, abdominal obesity, diabetes, hyperlipidemia, hypercholesterolemia, high LDL-C were positively correlated with hypertension, low HDL-C was negatively correlated with hypertension.

Association between Eight Functional Polymorphisms and Haplotypes in the Cholesterol Ester Transfer Protein (CETP) Gene and Dyslipidemia in National Minority Adults in the Far West Region of China

We have investigated the relationship between the polymorphisms and haplotypes in the CETP gene, and dyslipidemia among the Xinjiang Kazak and Uyghur populations in China. A total of 712 patients with dyslipidemia and 764 control subjects of CETP gene polymorphism at rs12149545, rs3764261, rs1800775, rs711752, rs708272, rs289714, rs5882, and rs1801706 loci were studied by the Snapshot method, linkage disequilibrium analysis and haplotype construction. The results are as follows: (1) the minor allele of eight loci of frequencies in the two groups were different from other results of similar studies in other countries; (2) In the linear regression analysis, the HDL-C levels of rs708272 TT, rs1800775 AA, rs289714 CC and rs711752 AA genotypes were significantly higher than those of other genotypes, however, the rs3764261 GG and rs12149545 GG genotypes were significantly lower than those of other genotypes in the two ethnic groups. The HDL-C levels of the rs12149545 GG genotype were lower than those of other genotypes; (3) in the control group, the rs708272 CT genotype of TG levels were lower than in the CC genotype, the T genotype of LDL-C levels were lower than in the CC genotype, and the HDL-C levels were higher than in the CT genotype; the rs1800775 AC genotype of TG levels were higher than in the AA genotype, the rs711752 AG genotype of TG levels were lower than in the GG genotype, the AA genotype LDL-C levels were lower than in the GG genotype, and the HDL-C levels were higher than in the AG genotype; the rs1800775 AC genotype of TG levels were higher than in the AA genotype. In the dyslipidemia group, the rs708272 TT genotype of TC and LDL-C levels were higher than in the CT genotype and the rs3764261 TT genotype of TC levels were higher than in the GG genotype. The rs711752 AA genotype of TC and LDL-C levels were higher than in the AG genotype, and the rs12149545 AA genotype of TC and LDL-C levels were higher than in the GG genotype; (4) perfect Linkage Disequilibrium was observed for two sets of two SNPs: rs3764261 and rs12149545; rs711752 and rs708272. (5) Using SHEsis software analysis, the five A/T/A/A/T/C/A/G, A/T/A/A/T/T/G/A, G/G/A/G/C/C/G/G, G/G/C/G/C/C/A/G and G/G/C/G/C/T/G/G haplotypes were between dyslipidemia group and control group statistically significantly different (p < 0.05 in each case). The polymorphism of CETP genes rs708272, rs3764261, rs1800775, rs711752, rs12149545 was closely related to the dyslipidemia in the Xinjiang Uyghur and Kazakh ethnic groups; and the rs708272 T, rs3764261 T, rs711752 A, and rs12149545 A alleles could reduce risk of dyslipidemia in the Uyghur and Kazakh populations, however, the rs1800775 C allele showed risk factors.

Ethnic Differences in the Prevalence of High Homocysteine Levels Among Low-Income Rural Kazakh and Uyghur Adults in Far Western China and Its Implications for Preventive Public Health

Objective: Homocysteine (Hcy) is a relevant biomarker of vascular disease: serum Hcy concentrations will increase the risk of systolic hypertension, whereas hyperhomocysteinemia (HHcy) has a synergistic effect with hypertension and increases the risk of cardiovascular disease. However, information has primarily been gathered from high-income and urban settings, and little is known regarding low-income rural settings. This study focused on a low-income rural and nomadic minority residing in far western China. Hcy levels were tested, and the prevalences of HHcy and H-type hypertension were investigated in this population. Methods: This study used a stratified cluster random sampling method, selecting 2,180 individuals as subjects from Kazakh and Uyghur inhabitants (≥25 years old) of 18 villages in Xinjiang, China, which is approximately 4407 km from the capital, Beijing. Hcy levels were determined using a double reagent enzymatic cycling method. HHcy (Hcy > 10 μmol/L) was defined by the criteria of the American Heart Association. Results: The Kazakh geometrical mean of Hcy was 13.34 μmol/L, and the Uyghur mean was 13.75 μmol/L; the mean values were higher in males than in females of both ethnicities (15.99 μmol/L vs. 11.63 μmol/L; 15.71 μmol/L vs. 11.91 μmol/L, respectively, p < 0.01). The serum levels of Hcy increased with increasing age in both ethnicities, and except for Kazakh individuals >65 years old, Hcy serum levels were higher in males than in females in all age groups of both ethnicities, with a p value less than 0.01. The Kazakh prevalence of HHcy was 80.0%, and the Uyghur prevalence was 78.2%; the male prevalence was higher than that in females for both ethnicities (93.5% vs. 69.6%; 90.8% vs. 64.6%, respectively, p < 0.05). Among the Kazakh, the prevalence of hypertension was 35.1%, and the prevalence was higher in males than in females (44.3% vs. 28.1%, p < 0.001); 87.6% of the Kazakh individuals had H-type hypertension, and the prevalence was higher in males than in females (95.0% vs. 80.0%, p < 0.05). In Uyghur, the prevalence of hypertension was 30.6%, and the prevalence was higher in males than in females (37.9% vs. 22.8%, p < 0.001); 88.0% of the Uyghur individuals had H-type hypertension, and the prevalence was higher in males than in females (93.9% vs. 79.1%, p < 0.05). Conclusions: HHcy was found to be common among the Kazakh and Uyghur. The prevalences of HHcy and H-type hypertension were high among both ethnicities and differed depending on gender and age. Community interventions should be conducted to improve public health conditions among the Kazakh and Uyghur in Xinjiang.