Supplementary Material for: Perinatal High-Fat Diet and Bisphenol A: Effects on Behavior and Gene Expression in the Medial Prefrontal Cortex

Both high-fat diets (HFD) and bisphenol A (BPA), an environmental endocrine disruptor, are prevalent in industrialized societies. Previous studies have detected separate effects of BPA and HFD; however, none have assessed possible interactive effects. Here, pregnant dams consumed 0, 40, or 400 µg BPA/kg/day and were fed either a control (CON; 15.8% kcal fat) or HFD (45% kcal fat) from gestational day 2 through parturition. The pups were individually dosed with BPA from postnatal days (P) 1–10, while the dams continued to consume one of the two diets. Maternal behavior increased with the HFD while the offspring’s periadolescent social play decreased with BPA, but no interactive effects were observed. Neither HFD nor BPA exposure changed performance on a social recognition task, and only BPA had an effect on the elevated plus maze. BPA increased several cytokines in the medial prefrontal cortex (mPFC) of P10 males but not females. Expression of several genes related to hormone synthesis and receptors, inflammation, oxidative stress, and apoptosis in the mPFC on P10 and P90 were altered due to BPA and/or HFD exposure with rare interactive effects. BPA resulted in an increase in the gene expression of <i>Esr1</i> in the mPFC of females on both P10 and P90. Epigenetic analysis on P90 did not show a change in methylation<i></i> or in the levels of pre-mRNA or microRNA. Thus, perinatal BPA and HFD have separate effects but rarely interact.

高脂饮食（high-fat diet, HFD）与环境内分泌干扰物双酚A（bisphenol A, BPA）在工业化社会中均呈广泛流行态势。既往研究已分别阐明BPA与HFD的独立生物学效应，但尚无研究评估二者可能存在的交互作用。本研究中，妊娠母鼠每日暴露0、40或400 μg BPA/kg体重，并从妊娠第2天至分娩全程喂食对照饲料（control diet, CON；热量占比15.8%的脂肪）或高脂饲料（HFD；热量占比45%的脂肪）。幼崽于出生后第1至10天（P1–P10）每日单独接受BPA染毒，同期母鼠仍维持两种饲料之一的喂食方案。研究结果显示，高脂饮食组母鼠的母性行为（maternal behavior）显著增强，而BPA暴露组子代的青春期前社交玩耍行为（periadolescent social play）明显减少，但未观察到二者的交互效应。HFD与BPA暴露均未改变受试对象在社交识别任务（social recognition task）中的行为表现，且仅BPA暴露对高架十字迷宫（elevated plus maze, EPM）测试结果存在显著影响。BPA暴露可使出生后第10天（P10）雄性幼崽内侧前额叶皮层（medial prefrontal cortex, mPFC）中的多种细胞因子（cytokine）水平升高，而雌性幼崽未出现该变化。在出生后第10天（P10）与第90天（P90）的内侧前额叶皮层中，与激素合成及受体、炎症反应（inflammation）、氧化应激（oxidative stress）、细胞凋亡（apoptosis）相关的多种基因表达均因BPA和/或HFD暴露发生显著改变，二者的交互效应较为罕见。BPA暴露可使出生后第10天及第90天雌性幼崽内侧前额叶皮层中Esr1基因的表达水平显著升高。对出生后第90天样本的表观遗传学分析（epigenetic analysis）未发现甲基化（methylation）水平、前体mRNA（pre-mRNA）或微小RNA（microRNA, miRNA）水平存在显著变化。综上，围产期（perinatal）BPA与HFD暴露各自产生独立生物学效应，但二者极少存在交互作用。