Air pollution is a public health concern that has been associated with adverse effects on the development and functions of the central nervous system (CNS). However, studies on the effects of exposure to pollutants on the CNS across the entire developmental period still remain scarce. In this study, we investigated the impacts of prenatal and/or postnatal exposure to fine particulate matter (PM_2.5) from São Paulo city, on the brain structure and behavior of juvenile male mice. BALB/c mice were exposed to PM_2.5 concentrated ambient particles (CAP) at a daily concentration of 600 μg/m³ during the gestational [gestational day (GD) 1.5–18.5] and the postnatal periods [postnatal day (PND) 22–90] to filtered air (FA) in both periods (FA/FA), to CAP only in the postnatal period (FA/CAP), to CAP only in the gestational period (CAP/FA), and to CAP in both periods (CAP/CAP). Behavioral tests were performed when animals were at PND 30 and PND 90. Glial activation, brain volume, cortical neuron number, serotonergic and GABAergic receptors, as well as oxidative stress, were measured. Mice at PND 90 presented greater behavioral changes in the form of greater locomotor activity in the FA-CAP and CAP-CAP groups. In general, these same groups explored objects longer and the CAP-FA group presented anxiolytic behavior. There was no difference in total brain volume among groups, but a lower corpus callosum (CC) volume was observed in the CAP-FA group. Also, the CAP-CAP group presented an increase in microglia in the cortex and an increased in astrocytes in the cortex, CC, and C1A and dentate gyrus of hippocampus regions. Gene expression analysis showed a decrease in BDNF in the hippocampus of CAP-CAP group. Treatment of immortalized glial cells with non-cytotoxic doses of ambient PM_2.5 increased micronuclei frequencies, indicating genomic instability. These findings highlight the potential for negative neurodevelopmental outcomes induced by exposure to moderate levels of PM_2.5 in Sao Paulo city.

空气污染是对公共卫生的关注，与对中枢神经系统（CNS）的发育和功能产生不利影响有关。然而，关于在整个发展时期内接触污染物对中枢神经系统影响的研究仍然很少。在这项研究中，我们调查了出生前和/或出生后暴露于圣保罗市细颗粒物（PM _2.5）对幼年雄性小鼠脑结构和行为的影响。BALB / c小鼠暴露于PM _2.5在妊娠[妊娠日（GD）1.5-18.5]和产后[产后日（PND）22-90]期间，将每天浓度为600μg/m³的浓缩环境颗粒（CAP）过滤后的空气（FA） （FA / FA），仅在产后时期（CAP / FA）进入CAP，仅在妊娠期（CAP / FA）进入CAP，以及两个时期都在CAP（CAP / CAP）。当动物分别处于PND 30和PND 90时进行行为测试。测量了神经胶质的激活，脑容量，皮层神经元数量，血清素能和GABA能受体以及氧化应激。PND 90的小鼠在FA-CAP和CAP-CAP组中表现出更大的行为变化，表现出更大的运动活动。通常，这些相同的小组探索对象的时间更长，而CAP-FA小组则表现出抗焦虑的行为。各组之间的总脑容量没有差异，但是在CAP-FA组中观察到较低的call体（CC）容量。此外，CAP-CAP组的皮层小胶质细胞增加，皮层，CC和C1A以及海马齿状回的星形胶质细胞增加。基因表达分析表明，CAP-CAP组海马BDNF减少。用无细胞毒性剂量的环境PM治疗永生胶质细胞_2.5增加的微核频率，表明基因组不稳定。这些发现凸显了圣保罗市由于暴露于中等水平的PM _2.5而导致的负面神经发育结果的潜力。