Zhen Cang

Is Exposure to Famine in Childhood and Economic Development in Adulthood Associated With Diabetes

CONTEXT The Chinese were afflicted by great famine between 1959 and 1962. These people then experienced rapid economic development during which the gross domestic product per capita increased from

Low vitamin D levels and non-alcoholic fatty liver disease, evidence for their independent association in men in East China: a cross-sectional study (Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China)).

28 in 1978 to

Blood lead level and its association with body mass index and obesity in China - Results from SPECT-China study

6807 in 2013. We hypothesize that these two events are associated with the booming rate of diabetes in China. OBJECTIVE We aimed to explore whether exposure to famine in early life and high economic status in adulthood was associated with diabetes in later life. DESIGN AND SETTING Our data of 6897 adults were from a cross-sectional Survey on Prevalence in East China for Metabolic Diseases and Risk Factors study in 2014. Among them, 3844 adults experienced famine during different life stages and then lived in areas with different economic statuses in adulthood. MAIN OUTCOME MEASURE Diabetes was considered as fasting plasma glucose of 7.0 mmol/L or greater, hemoglobin A1c of 6.5% or greater, and/or a previous diagnosis by health care professionals. RESULTS Compared with nonexposed subjects, famine exposure during the fetal period (odds ratio [OR]1.53, 95% confidence interval [CI]1.09-2.14) and childhood (OR 1.82, 95% CI 1.21-2.73) was associated with diabetes after adjusting for age and gender. Further adjustments for adiposity, height, the lipid profile, and blood pressure did not significantly attenuate this association. Subjects living in areas with high economic status had a greater diabetes risk in adulthood (OR 1.46, 95% CI 1.20-1.78). In gender-specific analyses, fetal-exposed men (OR 1.64, 95% CI, 1.04-2.59) and childhood-exposed women (OR 2.81, 95% CI, 1.59-4.97) had significantly greater risk of diabetes. CONCLUSIONS The rapid increase in the prevalence of diabetes in middle-aged and elderly people in China is associated with the combination of exposure to famine during the fetal stage and childhood and high economic status in adulthood. Our findings may partly explain the booming diabetes phenomenon in China.

Modulation of Microbiota-Gut-Brain Axis by Berberine Resulting in Improved Metabolic Status in High-Fat Diet-Fed Rats

Recent studies have suggested an association between vitamin D and non-alcoholic fatty liver disease (NAFLD); however, some results are subject to debate. This study was carried out to evaluate the correlation between NAFLD and vitamin D in men and women in East China. The data were obtained from a cross-sectional study that focused on the health and metabolic status of adults in sixteen areas of East China. According to ultrasonic assessments, the patients were divided into normal and NAFLD groups. Demographic characteristics and biochemical measurements were obtained. Binary logistic regression analysis was used to explore the association. In total, 5066 subjects were enrolled, and 2193 (43·3 %) were diagnosed with NAFLD; 84·56 % of the subjects showed vitamin D deficiency. Subjects with high vitamin D levels had a lower prevalence of NAFLD, particularly male subjects. Within the highest quartile of vitamin D levels, the prevalence of NAFLD was 40·8 %, whereas the lowest quartile of vitamin D levels showed a prevalence of 62·2 %, which was unchanged in women across the vitamin D levels. Binary logistic analysis showed that decreased vitamin D levels were associated with an increased risk of NAFLD (OR 1·54; 95 % CI 1·26, 1·88). This study suggests that vitamin D levels are significantly associated with NAFLD and that vitamin D acts as an independent factor for NAFLD prevalence, particularly in males in East China. Vitamin D interventional treatment might be a new target for controlling NAFLD; elucidating the mechanism requires further research.

Lead Exposure Induces Weight Gain in Adult Rats, Accompanied by DNA Hypermethylation

We aimed to report environmental and blood lead level (BLL) in China, and investigate the relationship of BLL with body mass index (BMI) and obesity. 5558 subjects were enrolled from 16 sites in China. BLL was measured by atomic absorption spectrometry. Obesity was defined as BMI ≥ 30 kg/m2. Median (interquartile range) of BLL was 44.00 μg/L (29.00–62.16) for men and 37.79 μg/L (25.13–54.35) for women, about twice higher than in U.S. population. Subjects in rural and high-economic-status areas had significantly greater BLL (P < 0.001). However, in these areas, the lead levels in drinking water, river water and rice were comparable to or significantly lower than those in urban and low-economic-status areas. After adjustment for age, urbanization, economic status and metabolic factors, BLL was independently associated with BMI in women (P for trend < 0.001), but not in men. In fully adjusted model, increased quartiles of BLL were associated with significantly increased odds ratios of obesity (P for trend < 0.01) in women. In conclusion, BLLs in Chinese adults were much higher than in developed countries. There was a sex-specific association between BLL and BMI. Elevated BLL does not appear to be associated with lead levels in drinking water or rice, suggesting some other exposure source.

Hypothalamic-Pituitary-Gonadal Axis in Aging Men and Women: Increasing Total Testosterone in Aging Men

Objective: To investigate whether or not berberine could improve metabolic status of high-fat-fed rats through modulation of microbiota-gut-brain axis. Methods: Berberine was administered on high-fat-fed Sprague-Dawley rats. Brain-gut hormones were detected, and changes of gut microbiota were analyzed by 16S rRNA gene sequencing. Results: Berberine could reduce weight gain and lipolysis in the high-fat diet-fed group. Moreover, trends of ameliorated insulin resistance and decreased endogenous glucose production were observed. In addition, the microbiota-gut-brain axis was found to be modulated, including structural and diversity changes of microbiota, elevated serum glucagon-like peptide-1 and neuropeptide Y level, decreased orexin A level, up-regulated glucagon-like peptide-1 receptor mRNA level as well as ultra-structural improvement of the hypothalamus. Conclusion: Taken together, our findings suggest that berberine improved metabolic disorders induced by high-fat diet through modulation of the microbiota-gut-brain axis.

Investigation of vitamin D status and its correlation with insulin resistance in a Chinese population

Objective Previous studies have revealed the association of lead (Pb) exposure with obesity. DNA methylation alteration has been suggested to be one of the regulatory mechanisms of obesity. We aimed to explore whether Pb exposure is related with weight gain and DNA methylation alteration. Methods Male adult 8 week Wistar rats were divided into 5 groups: the normal chow diet (NCD); the NCD+0.05%Pb; the NCD+0.15%Pb; the NCD+0.45%Pb and the high fat diet. Rats were exposed to different dosages of Pb through drinking water for 21 weeks. Body weight, fasted blood glucose level, fasted insulin level, homeostasis assessment of insulin resistance (HOMA-IR) index and lipid profile were detected. Intra-peritoneal glucose tolerance test (IPGTT) was constructed to evaluate the glucose tolerance. Lipid accumulation of liver was detected and liver DNA underwent whole genome bisulfite sequencing. Results The NCD+0.05%Pb group had significantly greater weight, HOMA-IR and triglycerides, and lower glucose intolerance than the NCD group (P <0.05). This group also showed hepatic lipid accumulation. These metabolic changes were not observed in the other two Pb dosage groups. Furthermore, DNA hypermethylation extended along pathways related to glucose and lipid metabolism in NCD+0.05%Pb group. Conclusion Pb exposure resulted in dose-specific weight gain in adult Wistar rats, accompanied by alteration of DNA methylation.

Low Sex Hormone-Binding Globulin Levels Associate with Prediabetes in Chinese Men Independent of Total Testosterone.

Background: Aging is associated with variations in hypothalamic-pituitary-gonadal (HPG) axis hormones. However, it is not clear how aging changes these hormones. This study examined the natural alterations in the HPG axis in aging men and women in China. Methods: Data were obtained from our cross-sectional study (SPECT-China) in 16 areas of three provinces in East China between February and June 2014. There were 6,825 subjects selected, including 2,908 men and 3,917 women aged 25-93 years who had no diseases affecting HPG hormones and did not take exogenous supplements. Total testosterone (TT), estradiol (E2), free testosterone, sex hormone-binding globulin (SHBG), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were measured. Results: In men, the ranges of the 10-90th percentiles for each hormone were as follows: TT, 9.9-23.4 nmol/l; SHBG, 20.6-79.54 nmol/l; E2, 34.84-187 pmol/l. TT values were higher in men aged 25-30 years than in those aged 31-35 years and began to increase progressively at the age of 41-50 years until men reached their eighties. The unadjusted annual age trend (β) was 0.079 nmol/l/year (p < 0.001). A linear regression analysis, after full adjustment for demographic variables, metabolic factors, other hormones, lifestyle and co-morbidities, showed that higher TT levels were still associated with aging (p < 0.05). However, the ratio of TT to LH decreased with age (β = -0.272/year, p < 0.001). E2 and SHBG increased with age (β = 1.774 pmol/l/year and 1.118 nmol/l/year, respectively, p < 0.001). In women, the 10-90th percentile range of E2 was 32.79-565.8 pmol/l. E2 began to decrease at the age of 46-50 years, declined sharply at the age of 51-55 years (β = -5.73 pmol/l/year, p < 0.001) and then stabilized at a low concentration after the age of 55 years. The 10-90th percentile ranges of LH and FSH in men were 2.4-9.2 and 3.4-15.5 IU/l, and in women they were 3-36.6 and 4-89.28 IU/l, respectively. FSH increased by 7.11% per annum in men and by 12.76% per annum in women, but LH increased by only approximately 4.00% per annum in both sexes. Conclusions: The influence of aging on the HPG axis is sex dependent. The pattern of age-related TT was different in Chinese Han men when compared with previous studies in Western populations. TT values increased in aging men, so it is not suitable to estimate the life quality of older Chinese men just based on TT.

Sexual Dimorphism for the Association between Vitamin D and Insulin Resistance in Chinese People

OBJECTIVE Although many studies worldwide have focused on the relationship between vitamin D and insulin resistance, results remain controversial. Furthermore, concentrations of serum 25-hydroxyvitamin D (25(OH)D) in the Chinese population are unclear. We aimed to investigate vitamin D status and its correlation with insulin resistance among a Chinese adult population. DESIGN Serum 25(OH)D, fasting blood glucose, fasting insulin, glycated Hb (HbA1c) and other metabolic parameters were assessed. Neck circumference, waist circumference, hip circumference, weight and height were also measured. Lifestyle factors including smoking and drinking status were obtained. Diabetes mellitus was diagnosed by HbA1c according to the 2010 American Diabetes Association criteria. SETTING Eastern China. SUBJECTS Of 7200 residents included, 6597 individuals were ultimately analysed. RESULTS We enrolled 2813 males (mean age 52·7 (sd 13·5) years) and 3784 females (52·3 (sd 13·5) years); mean serum 25(OH)D concentration was 43·1 (sd 11·6) and 39·6 (sd 9·8) nmol/l, respectively. Additionally, 83·3 % of participants were 25(OH)D deficient. A significant difference in 25(OH)D was observed between males and females in winter and spring (P<0·001). Furthermore, 25(OH)D concentrations were inversely associated with the homeostasis model assessment of insulin resistance (HOMA-IR) in the overweight and pre-diabetic populations. After adjusting for several variables, 25(OH)D was significantly associated with HOMA-IR in winter. When 25(OH)D values were categorized into quartiles, HOMA-IR was significantly associated with decreasing 25(OH)D. CONCLUSIONS The majority of the Chinese population was vitamin D deficient and this deficiency was negatively associated with insulin resistance, particularly in the overweight and pre-diabetic populations. Moreover, these associations might be more evident in the winter.

Serum Uric Acid Is Associated with Erectile Dysfunction: A Population-Based Cross-Sectional Study in Chinese Men

Objective The association ns between prediabetes and androgens have been rarely reported, especially in Chinese men. We aimed to investigate whether androgens were associated with the prevalence of prediabetes diagnosed with new American Diabetes Association criteria in Chinese men and then to assess which androgen value was the most relevant factor. Methods A total of 2654 men (52.6±13.4 years old) were selected. Serum total testosterone (TT), sex hormone-binding globulin (SHBG) and free testosterone (FT) were measured. Covariance analysis of different androgen values were performed in age subgroups. Multinomial logistic regression was used for the association of TT, SHBG and FT with prediabetes and diabetes, as well as prediabetes in age subgroups. Results According to ADA new criteria, normoglycemia, prediabetes, and diabetes were diagnosed in 1405, 907 and 342 men, respectively. In covariance analysis, SHBG of prediabetes were found lower than that of normoglycemia but higher than that of diabetes (P <0.05). In multinomial logistic regression, serum TT and SHBG were inversely associated with prediabetes and diabetes. While, after full adjustment for age, residence area, economic status, waist circumference, metabolic factors, other two androgen values and HOMA-IR, only the associations of SHBG with prevalence of prediabetes and diabetes persisted statistically significant, especially in the elderly with prediabetes (all P for trend <0.05). Conclusions Serum androgen was inversely associated with prediabetes and diabetes in Chinese men. Low serum SHBG was the most relevant factor for prediabetes and diabetes. Whether it is an independent predictor for incident prediabetes in Chinese men needs further explorations.