Blood levels of perfluoroalkyl substances (PFASs), elements and their associations with metabolic syndrome (MetS) in Chinese male adults mediated by metabolic-related risk factors.

Our preliminary studies have suggested PFASs, heavy metals, and trace elements could bring significant risks to MetS. However, the role of epigenetic mechanisms (i.e., miRNAs) and risk factors of metabolic alternation (i.e., thyroid functions, glucose and lipids metabolism) are not fully understood. To test this hypothesis, a further cross-sectional study with 80 male MetS cases and 64 male references was undertaken. Negative association between the serum n-perfluorooctanoic acid (n-PFOA) with miR-140-5p was found [β = -0.772; 95% confidence interval (CI), -0.244 to -0.300; p < 0.01, q < 0.05)] after adjusted with age. Higher levels of leptin and total bile acid were observed in the MetS group. The significantly positive associations between leptin with Cd (β = 1.015, p < 0.01, q < 0.05), Cu (β = 6.796, p < 0.05, q = 0.077) and Se (β = 7.633, p < 0.05, q = 0.060) were found; whereas total bile acid was significantly associated with Se (β = 8.954, p < 0.05, q = 0.140). Significantly positive associations between leptin and systolic/diastolic blood pressure were showed. Moreover, increased total bile acid concentrations were associated with hypertriglyceridemia [odds ratio (OR): 2.24 (95%CI, 1.10-4.58) adjusted by age.