Exposure to persistent organic pollutants (POPs), encompassing chlorinated (Cl), brominated (Br) and perfluoroalkyl acid (PFAA) compounds is associated with adverse neurobehaviour in humans and animals, and is observed to cause adverse effects in nerve cell cultures. Most studies focus on single POPs, whereas studies on effects of complex mixtures are limited. We examined the effects of a mixture of 29 persistent compounds (Cl + Br + PFAA, named Total mixture), as well as 6 sub-mixtures on in vitro exposed rat cerebellar granule neurons (CGNs). Protein expression studies of cerebella from in vivo exposed mice offspring were also conducted. The selection of chemicals for the POP mixture was based on compounds being prominent in food, breast milk or blood from the Scandinavian human population. The Total mixture and sub-mixtures containing PFAAs caused greater toxicity in rat CGNs than the single or combined Cl/Br sub-mixtures, with significant impact on viability from 500x human blood levels. The potencies for these mixtures based on LC₅₀ values were Br + PFAA mixture > Total mixture > Cl + PFAA mixture > PFAA mixture. These mixtures also accelerated induced lipid peroxidation. Protection by the competitive N-methyl-D-aspartate (NMDA) receptor antagonist 3-((R)-2-Carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP) indicated involvement of the NMDA receptor in PFAA and Total mixture-, but not Cl mixture-induced toxicity. Gene-expression studies in rat CGNs using a sub-toxic and marginally toxic concentration ((0.4 nM-5.5 µM) 333x and (1 nM-8.2 µM) 500x human blood levels) of the mixtures, revealed differential expression of genes involved in apoptosis, oxidative stress, neurotransmission and cerebellar development, with more genes affected at the marginally toxic concentration. The two important neurodevelopmental markers Pax6 and Grin2b were downregulated at 500x human blood levels, accompanied by decreases in PAX6 and GluN2B protein levels, in cerebellum of offspring mice from mothers exposed to the Total mixture throughout pregnancy and lactation. In rat CGNs, the glutathione peroxidase gene Prdx6 and the regulatory transmembrane glycoprotein gene Sirpa were highly upregulated at both concentrations. In conclusion, our results support that early-life exposure to mixtures of POPs can cause adverse neurodevelopmental effects.

暴露于持久性有机污染物（POPs），其中包括氯化物（Cl），溴化物（Br）和全氟烷基酸（PFAA）化合物与人类和动物的不良神经行为有关，并被观察到会对神经细胞培养产生不利影响。大多数研究集中在单一的持久性有机污染物上，而对复杂混合物的影响的研究是有限的。我们检查了29种持久性化合物（Cl + Br + PFAA，称为总混合物）的混合物以及6种亚混合物对体外暴露的大鼠小脑颗粒神经元（CGNs）的影响。小脑体内蛋白质表达研究还进行了暴露的小鼠后代。持久性有机污染物混合物的化学物质选择是基于斯堪的纳维亚人口在食物，母乳或血液中突出的化合物。含有PFAA的总混合物和子混合物对大鼠CGN的毒性要比单一或组合的Cl / Br子混合物更大，对人类血液500倍水平的生存能力产生重大影响。基于LC ₅₀值，这些混合物的效力为Br + PFAA混合物>总混合物> Cl + PFAA混合物> PFAA混合物。这些混合物也加速了脂质过氧化的诱导。由竞争性N-甲基-D-天冬氨酸（NMDA）受体拮抗剂3-（（R）-2-羧哌嗪-4-基）-丙基-1-膦酸（CPP）表明NMDA受体参与了PFAA和总混合物诱导的毒性，但不涉及Cl混合物诱导的毒性。在大鼠CGN的基因表达研究中，使用该混合物的亚毒性和微毒性浓度（（0.4 nM-5.5 µM）333x和（1 nM-8.2 µM）500x人血水平），发现凋亡相关基因的差异表达，氧化应激，神经传递和小脑发育，在边缘毒性浓度下影响更多的基因。两个重要的神经发育标记Pax6和Grin2b在妊娠和哺乳期间，暴露于Total混合物的母亲的后代小鼠小脑中，其血液水平被下调至500倍人类血液水平，并伴随着PAX6和GluN2B蛋白水平的降低。在大鼠CGN中，两种浓度下的谷胱甘肽过氧化物酶基因Prdx6和调节性跨膜糖蛋白基因Sirpa都被上调。总之，我们的结果支持生命早期暴露于POPs混合物可能引起不良的神经发育作用。