Associations of Maternal rs1801131 Genotype in MTHFR and Serum Folate and Vitamin B12 with Gestational Diabetes Mellitus in Chinese Pregnant Women.

Circumstantial evidence links one-carbon metabolism (OCM) related nutrients, such as folate and vitamin B12, with gestational diabetes mellitus (GDM). However, few studies have evaluated the combined effects of these nutrients with OCM related gene polymorphisms on GDM. This study investigated whether OCM related genetic variants modified the associations of folate and B12 with GDM. Logistic regression was used to estimate odds ratios (ORs) for OCM related nutrients and single nucleotide polymorphisms (SNPs) in genes encoding main OCM related enzymes (MTHFR, MTR, and MTRR) on GDM. Higher folate concentrations were associated with increased GDM risk (OR: 1.59; 95% CI: 1.22, 2.13). However, higher B12 concentrations were associated with reduced GDM risk (OR: 0.76; 95% CI: 0.65, 0.92). Pregnancies with MTHFR rs1801131 G alleles had a significantly lower risk of GDM than pregnancies with T alleles (OR: 0.65; 95% CI: 0.47, 0.91) under the dominant model. The genotype-stratified analysis revealed the association between folate and GDM (OR: 1.66, 95% CI: 1.20, 2.30) or B12 and GDM (OR: 0.80, 95% CI: 0.65, 0.98) was more evident in pregnancies with TT genotype. Higher folate and lower B12 are associated with GDM. Pregnancies with MTHFR rs1801131 TT genotype are more susceptible to OCM nutrient-related GDM.

Associations of urinary phenolic environmental estrogens exposure with blood glucose levels and gestational diabetes mellitus in Chinese pregnant women.

BACKGROUND: Endocrine-disrupting chemicals (EDCs) are considered to be related to diabetes, but studies of the association between phenolic EDCs and gestational diabetes mellitus (GDM) are limited. OBJECTIVES: To assess associations of maternal urinary bisphenol A (BPA), nonylphenol (NP), and 2-tert-octylphenol (2-t-OP) with GDM occurrence. METHODS: A cross-sectional study was performed among 390 Chinese women at 24-28 weeks of gestation. GDM was diagnosed with a 2-h 75-g oral glucose tolerance test (OGTT). BPA, NP, and 2-t-OP concentrations were determined in urine samples. Linear and logistic regression tests evaluated associations of BPA, NP, and 2-t-OP with blood glucose levels and GDM prevalence. RESULTS: The 2-t-OP concentrations in GDM patients were significantly higher than in non-GDM women with median values of 2.23 µg/g Cr and 1.79 µg/g Cr, respectively. No significant difference was observed in BPA and NP. Urinary 2-t-OP was positively associated with blood glucose levels after adjustment for several confounding factors and urinary BPA and NP. Higher 2-t-OP levels were associated with higher odds of GDM (OR: 5.78; 95% CI: 2.04, 16.37), whereas higher NP levels were associated with lower odds (OR: 0.22; 95% CI: 0.05, 0.85) in the adjusted models. In addition, compared to the first quartile of 2-t-OP, the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for GDM in the second, third, and fourth quartiles were 2.81 (1.23, 6.42), 3.01 (1.30, 6.93), and 5.49 (2.24, 13.46), respectively. CONCLUSION: Our study indicates that, for the first time to our knowledge, exposure to 2-t-OP is associated with a higher risk of GDM. However, higher NP exposure is associated with lower GDM risk. Further studies are necessary to affirm the associations of 2-t-OP and NP with GDM, and to elucidate the causality of these findings.

Risk Score for Detecting Dysglycemia: A Cross-Sectional Study of a Working-Age Population in an Oil Field in China.

BACKGROUND Dysglycemia (pre-diabetes or diabetes) in young adults has increased rapidly. However, the risk scores for detecting dysglycemia in oil field staff and workers in China are limited. This study developed a risk score for the early identification of dysglycemia based on epidemiological and health examination data in an oil field working-age population with increased risk of diabetes. MATERIAL AND METHODS Multivariable logistic regression was used to develop the risk score model in a population-based, cross-sectional study. All subjects completed the questionnaires and underwent physical examination and oral glucose tolerance tests. The performance of the risk score models was evaluated using the area under the receiver operating characteristic curve (AUC). RESULTS The study population consisted of 1995 participants, 20-64 years old (49.4% males), with undiagnosed diabetes or pre-diabetes who underwent periodic health examinations from March 2014 to June 2015 in Dagang oil field, Tianjin, China. Age, sex, body mass index, history of high blood glucose, smoking, triglyceride, and fasting plasma glucose (FPG) constituted the Dagang dysglycemia risk score (Dagang DRS) model. The performance of Dagang DRS was superior to m-FINDRISC (AUC: 0.791; 95% confidence interval (CI), 0.773-0.809 vs. 0.633; 95% CI, 0.611-0.654). At the cut-off value of 5.6 mmol/L, the Dagang DRS (AUC: 0.616; 95% CI, 0.592-0.641) was better than the FPG value alone (AUC: 0.571; 95% CI, 0.546-0.596) in participants with FPG <6.1 mmol/L (n=1545, P=0.028). CONCLUSIONS Dagang DRS is a valuable tool for detecting dysglycemia, especially when FPG <6.1 mmol/L, in oil field workers in China.

[Study on the expression of uncoupling protein 2 in the kidney of the rats with hypothyroidism].

OBJECTIVE: To observe the change in the expression of uncoupling protein 2 (UCP2) in kidney mitochondria in rats with hypothyroidism, and study the mechanism of renal injury due to hypothyroidism. METHODS: The Wistar rats were randomly divided into control group (n=10) and hypothyroidism group (n=10). The hypothyroidism rat model was reproduced by low-iodine diet. The intake of iodine in control group and hypothyroidism group were 10.00 µg/d and 1.24 µg/d, respectively. The rats were raised under these conditions respectively for 3 months after they adapted to the feeding for 1 week. Then the thyroid function parameters were measured in blood, and the expressions of UCP2 protein and mRNA in renal tissue were measured by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) methods. RESULTS: The thyrotropic-stimulating hormone (TSH, mU/L) in hypothyroidism group was significantly higher than that in control group (4.88±1.37 vs. 1.65±0.33, P<0.05). The levels of total triiodothyronine (TT(3)), total thyroxine (TT(4)), free triiodothyronine (FT(3)) and free thyroxine (FT(4)) in serum in hypothyroidism group were significantly lower than those in control group [TT(3) (nmol/L) : 0.54±0.07 vs. 0.98±0.17, TT(4) (nmol/L): 7.82±2.18 vs. 48.78±3.65, FT(3) (pmol/L): 2.28±0.22 vs. 2.99±0.10, FT(4) (pmol/L): 11.38±1.74 vs. 29.27±0.95, all P<0.01]. The immunohistochemistry study revealed that the UCP2 protein expression in both renal glomeruli and tubule tissues in the hypothyroidism group was significantly lower than that of control group (renal glomeruli: 0.17±0.02 vs. 0.24±0.04, renal tubule: 0.19±0.02 vs. 0.25±0.02, both P<0.01). The RT-PCR showed that the UCP2 mRNA expression in the hypothyroidism group was significantly lower than that of control group (0.70±0.19 vs. 1.30±0.09, P<0.01). CONCLUSION: Hypothyroidism may produce damage to kidney, which is related to the down-regulation of UCP2 expression in the mitochondria of renal cells.