Prenatal LPS-induced changes in gene expression

描述（由申请人提供）：我们先前证明，用细菌毒素脂多糖（LPS）处理的妊娠雌性所生的幼崽出生时多巴胺（DA）神经元少于正常。我们将这些研究延长至16个月，结果表明，大鼠产前暴露于LPS后，表现出与DA活性增加、促炎细胞因子肿瘤坏死因子（TNF α）升高、α-突触核蛋白聚集和路易样小体相关的DA神经元进行性丢失（46%）。我们最近收到了NINDS的资助，通过22个月来描述这种新的帕金森病（PD）动物模型。然而，目前尚不清楚发育过程中DA神经元丢失的机制。最近的初步数据（实时RT-PCR）表明，促/抗炎细胞因子mRNA的比例增加。因此，在具体目标1中，我们将评估中脑、纹状体和小脑（对照区）中TNF-α、白细胞介素（IL）-113、IL-6、转化生长因子（TGF β）和IL-6的mRNA和细胞因子蛋白（ELISA）含量，以确定产前LPS是否改变发育期间或出生后早期这些因子的转录和翻译控制（P1 -21）。由于Nurr-1，音刺猬，Ptx-3，成纤维细胞生长因子-8（FGF 8）和胶质细胞系衍生的神经营养因子（GDNF）分别是转录和神经营养因子，调节DA神经元表型的发育，我们将评估这些因子的mRNA和蛋白质水平在特定目标2中，以确定它们参与LPS诱导的DA神经元减少。我们的初步数据进一步表明，LPS诱导小胶质细胞中TNF-α的增加，我们将在Aim 3中评估小胶质细胞和星形胶质细胞在LPS作用中的具体作用。这些研究的结果不仅将补充我们的长期研究，但将测试的假设，产前LPS永久改变基因，调节DA神经元的发展，并影响其表型在成年生活。这些研究的结果也将提供一个独特的机会，以确定产前神经毒素暴露是否可以永久改变基因，增加以后生活中神经退行性疾病的风险。

DESCRIPTION (provided by applicant): We previously demonstrated that pups born to gravid females treated with the bacteriotoxin lipopolysaccharide (LPS) were born with fewer than normal dopamine (DA) neurons. We have extended these studies out through 16 months and showed that rats exposed to LPS prenatally exhibit progressive loss of DA neurons (46%) associated with increased DA activity, elevations in the proinflammatory cytokine tumor necrosis factor (TNFalpha), aggregates of alpha-synuclein, and Lewy-like bodies. We have recently received funding from NINDS to characterize this new animal model of Parkinson's disease (PD) through 22 months. However, the mechanism(s) responsible for this DA neuron loss during development are currently unknown. Recent preliminary data (Real-time RT-PCR) suggests that the ratio of pro-/anti-inflammatory cytokine mRNA is increased. In specific aim 1 we will therefore assess both mRNA and cytokine protein (ELISA) content for TNF-a, interleukin (IL) -113, IL-6, transforming growth factor (TGFbeta), and IL-6 in the mesencephalon, striatum, and cerebellum (control region) to determine if prenatal LPS alters transcriptional and translational control of these factors during development or early postnatal life (P 1-21). Since Nurr-1, sonic hedgehog, Ptx-3, fibroblast growth factor-8 (FGF8) and glial cell line derived neurotrophic factor (GDNF) are transcriptional and neurotrophic factors, respectively, that regulate the development of the DA neuron phenotype, we will assess mRNA and protein levels of these factors in Specific Aim 2 to determine their involvement in the LPS-induced reduction in DA neurons. Our preliminary data further suggests that LPS induces increases in TNF-alpha in microglia and we will assess the specific roles of both microglia and astrocytes in the LPS effect in Aim 3. The results of these studies will not only compliment our long-term studies, but will test the hypothesis that prenatal LPS permanently alters genes that regulate the development of the DA neuron and affect its phenotype during adult life. The results of these studies will also provide a unique opportunity to determine if prenatal neurotoxin exposure can permanently alter genes that increase the risk of neurodegenerative disease in later life.