Regulation of the sphingomyelin pathway in the CL

CL 中鞘磷脂途径的调节

• 批准号: 6897138
• 负责人: Bo R. RUEDA
• 金额: $ 29.98万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-08 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6897138
• 关键词: apoptosis; biological signal transduction; cell membrane; ceramides; corpus luteum; cytokine; cytotoxicity; gene targeting; genetically modified animals; hydrolysis; immunocytochemistry; laboratory mouse; mitochondrial membrane; mitogen activated protein kinase; phosphatidylinositol 3 kinase; phosphorylation; progesterone; prostaglandin F; sphingomyelin phosphodiesterase; sphingomyelins; steroid hormone biosynthesis; tissue /cell culture; tumor necrosis factor alpha; western blottings

DESCRIPTION (provided by applicant): Luteolysis is multi-faceted involving numerous effectors that utilize multiple cellular signaling mechanisms. These effectors and the mechanisms by which they elicit their responses are not by themselves sufficient to explain the process of luteolysis in its entirety. Thus, other mediators must be involved. Cytokines, once thought to be secondary in the luteolytic process, are proving to be active players. Recent evidence suggests that cytokines (FasL and TNFalpha) signal via intermediates of the sphingomyelin pathway including sphingomyelinases (acid or neutral) and ceramide. The sphingomyelin pathway is a novel pathway involved in modulating cell signaling and cell death. There is also evidence that ceramide can regulate gonadotropin-induced steroidogenesis. Whether this is a direct effect, a by-product of altered membrane fluidity or due to disruption of pro-survival signaling is unknown. It is also possible that these events are pivotal to the structural involution of the CL. We hypothesize that ceramide generated at multiple sites within luteal cells mediates luteolysis. More specifically, an increase in the levels of ceramide via acid sphingomyelinase hydrolysis in the inner and/or outer leaflet of the plasma membrane alters the hierarchy of lipid ordering in the cellular membranes. Consequently, gonadotropin and PI(3)kinase signaling is inhibited, accelerating loss of function. Concomitantly, an increase in ceramide at the level of the mitochondria via ceramide synthase results in perturbation of the mitochondrial membrane contributing to loss of function and activation of the apoptosome. This hypothesis will be tested by the following Specific Aims: 1) determine if acid sphingomyelinase is functionally required in mouse CL for the disruption of steroidogenesis and induction of apoptosis using in vitro and in vivo models, 2) determine the mechanism(s) by which ceramide generated at the plasma membrane contributes to cytokine-induced loss of function or luteal cell death 3) determine at what cellular level TNFa inhibits gonadotropin-stimulated progesterone production in the CL, 4) ascertain whether increased levels of ceramide result in inhibition of the PI(3)-kinase by sequestering PI(3)-kinase in the caveolae fraction of luteal cells, and 5) establish if PGF2u or cytokine-mediated luteal cell apoptosis require involvement of the mitochondria and whether or not ceramide potentiates the dysregulation of mitochondrial function.

描述（由申请人提供）：黄体溶解是多方面的，涉及许多利用多种细胞信号传导机制的效应物。这些效应物和它们引起反应的机制本身不足以解释整个黄体溶解过程。因此，其他调解人必须参与。细胞因子，曾经被认为是次要的溶黄体过程中，被证明是积极的球员。最近的证据表明，细胞因子（FasL和TNF α）信号通过鞘磷脂途径的中间体，包括鞘磷脂酶（酸性或中性）和神经酰胺。鞘磷脂途径是一种参与调节细胞信号传导和细胞死亡的新途径。也有证据表明，神经酰胺可以调节促性腺激素诱导的类固醇生成。这是否是一个直接的影响，改变膜流动性的副产品或由于破坏促生存信号是未知的。这些事件也可能是CL结构内卷的关键。我们推测，神经酰胺产生于黄体细胞内的多个部位，介导了黄体溶解。更具体地说，通过质膜内叶和/或外叶中的酸性鞘磷脂酶水解增加神经酰胺水平改变了细胞膜中脂质排序的层次结构。因此，促性腺激素和PI（3）激酶信号被抑制，加速功能丧失。同时，通过神经酰胺合酶在线粒体水平上增加神经酰胺导致线粒体膜的扰动，导致线粒体功能丧失和激活。该假设将通过以下具体目标进行检验：1）使用体外和体内模型确定酸性鞘磷脂酶在小鼠CL中是否是破坏类固醇生成和诱导细胞凋亡的功能所需的，2）确定在质膜上产生的神经酰胺导致甜菜碱诱导的功能丧失或黄体细胞死亡的机制3）确定TNF α在何种细胞水平抑制CL中促性腺激素刺激的孕酮产生，4）确定增加的神经酰胺水平是否通过在黄体细胞的小窝部分中隔离PI（3）-激酶而导致PI（3）-激酶的抑制，和5）确定PGF 2u或精氨酸介导的黄体细胞凋亡是否需要线粒体参与，以及神经酰胺是否增强线粒体功能的失调。

项目成果

Caspase-3 Is a Pivotal Mediator of Apoptosis during Regression of the Ovarian Corpus Luteum.

• DOI: 10.1210/endo.143.4.8726
• 发表时间: 2002-04
• 期刊: Endocrinology
• 影响因子: 4.8
• 作者: S. Carambula;T. Matikainen;M. P. Lynch;R. Flavell;Paulo B Dias Gonc Alves;J. Tilly;B. Rueda

Signaling mechanisms in tumor necrosis factor alpha-induced death of microvascular endothelial cells of the corpus luteum.

• DOI: 10.1186/1477-7827-1-17
• 发表时间: 2003-02-11
• 期刊: Reproductive biology and endocrinology : RB&E
• 作者: Pru, James K;Lynch, Maureen P;Rueda, Bo R
• 通讯作者: Rueda, Bo R

Microvascular endothelial cells of the bovine corpus luteum: a comparative examination of the estrous cycle and pregnancy.

牛黄体的微血管内皮细胞：动情周期和妊娠的比较检查。

• DOI: 10.1262/jrd.19182
• 发表时间: 2008
• 期刊: The Journal of reproduction and development
• 作者: Cherry,JessicaAnn;Hou,Xiaoying;Rueda,BoRuben;Davis,JohnStewart;Townson,DavidHarrison
• 通讯作者: Townson,DavidHarrison

Microvascular endothelial cells of the corpus luteum.

• DOI: 10.1186/1477-7827-1-89
• 发表时间: 2003-11-10
• 期刊: Reproductive biology and endocrinology : RB&E
• 作者: Davis, John S;Rueda, Bo R;Spanel-Borowski, Katherina
• 通讯作者: Spanel-Borowski, Katherina

Prostaglandin F2alpha- and FAS-activating antibody-induced regression of the corpus luteum involves caspase-8 and is defective in caspase-3 deficient mice.

• DOI: 10.1186/1477-7827-1-15
• 发表时间: 2003-02-11
• 期刊: REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY
• 影响因子: 4.4
• 作者: Carambula, Silvia F;Pru, James K;Lynch, Maureen P;Matikainen, Tiina;Goncalves, Paulo Bayard D;Flavell, Richard A;Tilly, Jonathan L;Rueda, Bo R
• 通讯作者: Rueda, Bo R