P2X7 Receptors Drive Poly(I:C) Induced Autism-like Behavior in Mice.

Maternal immune activation (MIA) is a principal environmental risk factor contributing to autism spectrum disorder (ASD), which compromises fetal brain development at critical periods of pregnancy and might be causally linked to ASD symptoms. We report that endogenous activation of the purinergic ion channel P2X7 (P2rx7) is necessary and sufficient to transduce MIA to autistic phenotype in male offspring. MIA induced by poly(I:C) injections to P2rx7 WT mouse dams elicited an autism-like phenotype in their offspring, and these alterations were not observed in P2rx7-deficient mice, or following maternal treatment with a specific P2rx7 antagonist, JNJ47965567. Genetic deletion and pharmacological inhibition of maternal P2rx7s also counteracted the induction of IL-6 in the maternal plasma and fetal brain, and disrupted brain development, whereas postnatal P2rx7 inhibition alleviated behavioral and morphological alterations in the offspring. Administration of ATP to P2rx7 WT dams also evoked autistic phenotype, but not in KO dams, implying that P2rx7 activation by ATP is sufficient to induce autism-like features in offspring. Our results point to maternal and offspring P2rx7s as potential therapeutic targets for the early prevention and treatment of ASD.SIGNIFICANCE STATEMENT Autism spectrum disorder (ASD) is a neurodevelopmental psychiatric disorder caused by genetic and environmental factors. Recent studies highlighted the importance of perinatal risks, in particular, maternal immune activation (MIA), showing strong association with the later emergence of ASD in the affected children. MIA could be mimicked in animal models via injection of a nonpathogenic agent poly(I:C) during pregnancy. This is the first report showing the key role of a ligand gated ion channel, the purinergic P2X7 receptor in MIA-induced autism-like behavioral and biochemical features. We show that genetic or pharmacological inhibition of both maternal and offspring P2X7 receptors could reverse the compromised brain development and autistic phenotype pointing to new possibilities for prevention and treatment of ASD.

Horváth G ，Otrokocsi L ，Beko K ，Baranyi M ，Kittel Á ，Fritz-Ruenes PA ，Sperlágh B ... -  《-》

Maternal P2X7 receptor inhibition prevents autism-like phenotype in male mouse offspring through the NLRP3-IL-1β pathway.

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition caused by interactions of environmental and genetic factors. Recently we showed that activation of the purinergic P2X7 receptors is necessary and sufficient to convert maternal immune activation (MIA) to ASD-like features in male offspring mice. Our aim was to further substantiate these findings and identify downstream signaling pathways coupled to P2X7 upon MIA. Maternal treatment with the NLRP3 antagonist MCC950 and a neutralising IL-1β antibody during pregnancy counteracted the development of autistic characteristics in offspring mice. We also explored time-dependent changes of a widespread cytokine and chemokine profile in maternal blood and fetal brain samples of poly(I:C)/saline-treated dams. MIA-induced increases in plasma IL-1β, RANTES, MCP-1, and fetal brain IL-1β, IL-2, IL-6, MCP-1 concentrations are regulated by the P2X7/NLRP3 pathway. Offspring treatment with the selective P2X7 receptor antagonist JNJ47965567 was effective in the prevention of autism-like behavior in mice using a repeated dosing protocol. Our results highlight that in addition to P2X7, NLRP3, as well as inflammatory cytokines, may also be potential biomarkers and therapeutic targets of social deficits and repetitive behaviors observed in autism spectrum disorder.

Szabó D ，Tod P ，Gölöncsér F ，Román V ，Lendvai B ，Otrokocsi L ，Sperlágh B ... -  《-》

Exogenous PD-L1 binds to PD-1 to alleviate and prevent autism-like behaviors in maternal immune activation-induced male offspring mice.

Zeng X ，Fan L ，Qin Q ，Zheng D ，Wang H ，Li M ，Jiang Y ，Wang H ，Liu H ，Liang S ，Wu L ，Liang S ... -  《-》

Oral probiotic administration during pregnancy prevents autism-related behaviors in offspring induced by maternal immune activation via anti-inflammation in mice.

Maternal immune activation (MIA) is associated with an increased risk for autism spectrum disorders (ASD) in offspring. Animal experiments have found that interleukin 6 (IL-6) and IL-17a are key cytokines in the induction of ASD by MIA. Moreover, probiotics were verified to inhibit the production of proinflammatory cytokines. Therefore, we investigated whether the administration of oral probiotics during pregnancy might protect the offspring that have suffered MIA from developing ASD. Probiotics were orally administered to pregnant mice with/without the simultaneous administration of Poly(I:C). We found that oral probiotics prevented the ASD-like behaviors induced by MIA in offspring. Furthermore, oral probiotics prevented the MIA-induced increases in the IL-6 and IL-17a levels in both maternal serum and fetal brains, parvalbumin positive (PV+ ) neuron loss, and the decrease in the γ-aminobutyric acid levels in the prefrontal cortex of adult offspring. This work suggests that administering oral probiotics during pregnancy may help decrease the risk of ASD following MIA during pregnancy. Autism Res 2019, 12: 576-588. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Interleukin 6 (IL-6) and IL-17a are key cytokines in the maternal immune activation (MIA)-induced autism spectrum disorders (ASD). Based on emerging evidence that probiotics can inhibit the production of proinflammatory cytokines, we found that oral probiotics prevented MIA-induced ASD-like behaviors in offspring. This work suggested that oral probiotics during pregnancy may be an effective means for decreasing the incidence of ASD in offspring.

Wang X ，Yang J ，Zhang H ，Yu J ，Yao Z ... -  《-》

NOX1/NADPH oxidase affects the development of autism-like behaviors in a maternal immune activation model.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder caused by genetic and environmental factors. Among the environmental factors, maternal infection is known as one of the principal risk factors for ASD. On the other hand, postmortem studies suggested the relationship of oxidative stress with ASD etiology. However, the role of oxidative stress in the development of ASD remains unclear. Here, we report the involvement of NOX1/NADPH oxidase, an enzyme generating reactive oxygen species (ROS), in behavioral and anatomical abnormalities in a maternal immune activation (MIA) model. In the MIA model of gestational polyinosinic-polycytidylic acid (poly(I:C)) exposure, increased serum levels of IL-6 were observed in both wild-type (WT) and Nox1-deficient mice (Nox1KO). Following the comparable induction of MIA in the two genotypes, impairment of social preference and defects in motor coordination were observed in WT offspring but not in offspring deficient in Nox1. MIA up-regulated NOX1 mRNA in the cerebral cortex and cerebellum of the fetus but not in the adult offspring. Although the development of cortical neurons was unaffected by MIA in either genotype, the dropout of Purkinje cells in lobule VII of MIA-affected offspring was significantly ameliorated in Nox1KO. Taken together, these results suggested that NOX1/NADPH oxidase plays an essential role in some behavioral phenotypes observed in ASD, possibly by promoting the loss of Purkinje cells in the cerebellum.

Zhang X ，Ibi M ，Haga R ，Iwata K ，Matsumoto M ，Asaoka N ，Liu J ，Katsuyama M ，Yabe-Nishimura C ... -  《-》