Abstract：
Polycystic ovary syndrome (PCOS) severely affects women\'s fertility and accompanies serious metabolic disturbances, affecting 5%-20% of women of reproductive age globally. We previously found that exposure to toxic metals in the blood raised the risk of PCOS, but the association between exposure to toxic metals and the risk of PCOS in the follicular fluid, the microenvironment for oocyte growth and development in females, and its effect on metabolism has not been reported. This study aimed to evaluate the associations between the concentrations of cadmium (Cd), mercury (Hg), barium (Ba) and arsenic (As) in FF and the risk of PCOS, and to explore the mediating effect of metabolic markers in FF on the above relationship. We conducted a case-control study, including 557 women with PCOS and 651 controls. Ba, Cd, Hg and As levels in FF were measured by ICP-MS, metabolites levels in FF was measured by LC-MS/MS among 168 participants randomly selected from all the participants. Logistic regression models were used to assess the association of a single metal level with the PCOS risk, and linear regression models were used to assess the relationships of a single metal level with clinical phenotype parameters and metabolites levels. Combined effect of metals mixture levels on the risk of PCOS were assessed via weighted quantile sum (WQS) regression and bayesian kernel machine regression (BKMR). Medication analysis was performed to explore the role of metabolic markers on the relationship of toxic metals levels with the risk of PCOS. The exposure levels of Cd, Hg, Ba and As in FF were all positively and significantly associated with the PCOS risk (with respect to the highest vs. lowest tertile group: OR = 1.57, 95% CI = 1.17 ~ 2.12 for Cd, OR = 1.69, 95% CI = 1.22 ~ 2.34 for Hg, OR = 1.76, 95% CI = 1.32 ~ 2.34 for Ba, OR = 1.42, 95% CI = 1.05 ~ 1.91 for As). In addition, levels of metal mixture also significantly correlated with the risk of PCOS, Cd level contributed most to it. Moreover, we observed significant positive relationships between Cd level and LH (β = 0.048, 95% CI = 0.002 ~ 0.094), T (β = 0.077, 95% CI = 0.029 ~ 0.125) and HOMA-IR value (β = 0.060, 95% CI = 0.012 ~ 0.107), as well as Hg level with LH, FSH/LH ratio and TC. Furthermore, we revealed that estrone sulfate, LysoPE 22:6 and N-Undecanoylglycine were significantly and positively mediating the association between Cd level and the risk of PCOS (with mediated proportion of 0.39, 0.24 and 0.35, respectively), and between Hg level and the risk of PCOS (with mediated proportion of 0.29, 0.20 and 0.46, respectively). These highly expressed metabolites significantly enriched in the fatty acid oxidation, steroid hormone biosynthesis and glycerophospholipids metabolism, which may explain the reason why the levels of Cd and Hg in FF associated with the phenotype of PCOS. Ba and As in FF was not found the above phenomenon. Our results suggested that exposure to multiple toxic metals (Cd, Hg, Ba and As) in FF associated with the increased risk of PCOS, Cd was a major contributor. Levels of Cd and Hg in FF significantly associated with the phenotype of PCOS. The above association may result from that Cd and Hg in FF related with the disturbance of fatty acid oxidation, steroid hormone biosynthesis and the glycerophospholipids metabolism.
摘要：
多囊卵巢综合征（PCOS）严重影响女性的生育能力，并伴随着严重的代谢紊乱，影响全球5％-20％的育龄妇女。我们以前发现，暴露于血液中的有毒金属会增加PCOS的风险，但是暴露于有毒金属与卵泡液中PCOS风险之间的关联，雌性卵母细胞生长和发育的微环境，其对新陈代谢的影响尚未见报道。本研究旨在评估镉（Cd）浓度之间的关联，汞(Hg),FF中的钡（Ba）和砷（As）与PCOS的风险，探讨代谢标志物在FF中的中介作用。我们进行了病例对照研究,包括557名PCOS女性和651名对照。Ba,Cd,通过ICP-MS测量FF中的Hg和As水平，在从所有参与者中随机选择的168名参与者中,通过LC-MS/MS测量FF中的代谢物水平.Logistic回归模型用于评估单一金属水平与PCOS风险的相关性，和线性回归模型用于评估单一金属水平与临床表型参数和代谢物水平的关系。通过加权分位数和（WQS）回归和贝叶斯核机回归（BKMR）评估金属混合物水平对PCOS风险的综合影响。进行药物分析以探讨代谢标志物在有毒金属水平与PCOS风险关系中的作用。镉的暴露水平，Hg,FF中的Ba和As均与PCOS风险呈正相关且显着相关(相对于最高vs.最低三元组:Cd的OR=1.57,95%CI=1.17~2.12,汞的OR=1.69，95%CI=1.22~2.34，Ba的OR=1.76，95%CI=1.32~2.34，对于As），OR=1.42，95%CI=1.05~1.91。此外,金属混合物的水平也与PCOS的风险显着相关，Cd水平对其贡献最大。此外，我们观察到Cd水平与LH之间存在显着正相关（β=0.048，95％CI=0.002〜0.094），T(β=0.077,95%CI=0.029~0.125)和HOMA-IR值(β=0.060,95%CI=0.012~0.107),以及LH的Hg水平，FSH/LH比值和TC。此外，我们发现硫酸雌酮，LysoPE22:6和N-十一酰甘氨酸显著正介导Cd水平与PCOS风险之间的关联（介导比例分别为0.39、0.24和0.35），以及Hg水平与PCOS风险之间的差异（介导比例分别为0.29、0.20和0.46）。这些高表达代谢产物显著富集脂肪酸氧化，类固醇激素生物合成和甘油磷脂代谢，这可以解释FF中Cd和Hg水平与PCOS表型相关的原因。Ba和As在FF中未发现上述现象。我们的结果表明，暴露于多种有毒金属(Cd，Hg,Ba和As)在FF中与PCOS风险增加相关，Cd是主要贡献者。FF中Cd和Hg水平与PCOS表型显著相关。上述关联可能是由于FF中的Cd和Hg与脂肪酸氧化的干扰有关。类固醇激素生物合成和甘油磷脂代谢。
