EFFECTS OF ETHANOL ON APOPTOSIS

慢性酒精中毒的组织损伤机制及 与胎儿酒精综合征相关的发育异常 未知然而，酒精引起的组织损伤通常与 具有程序性细胞死亡特征的孤立细胞损失， 凋亡，而不是坏死形式的损伤。在这方面我们 最近已经证明，乙醇显着敏感细胞， 通过抑制胰岛素样受体酪氨酸激酶活性， 生长因子I受体（IGF-IR），是一种对生存至关重要的受体， 许多细胞类型。我们假设乙醇诱导的毒性是 至少部分地通过IGF-IR的表达和激活来调节。 表现出紧密生长的鼠成纤维细胞和神经胶质细胞系 因子调节，特别是IGF-I，将用作体外模型， 测试乙醇对细胞凋亡启动的各种模式的影响。的 乙醇对细胞凋亡的促进作用与IGF-IR有关 表达和酪氨酸自磷酸化，以及表达和 激活关键的近端信号介质，如胰岛素相关的 底物-1（IRS-1）、Src-同源2/α-胶原（Shc）和磷脂酰 肌醇3-激酶乙醇对IGF-IR和细胞凋亡的影响 在啮齿动物和鸡的原代神经元细胞培养物中以及在 体内模型具体来说，我们将分析乙醇对 发育中的鸡，胎儿酒精综合征的既定模型，和 神经嵴细胞死亡与IGF-IR的发育动力学相关 表情细胞死亡也将研究使用植入式生物扩散 乙醇中毒小鼠的室中。 最后，我们将使用一本小说 功能表达克隆法鉴定IGF-I诱导型 生存基因我们将研究乙醇对表达的影响 这些基因，并确定是否过度表达的基因， 使细胞对乙醇的促凋亡作用不敏感。

The mechanisms of tissue injury in the setting of chronic alcoholism and developmental abnormalities associated with fetal alcohol syndrome are unknown. However, alcohol-induced tissue injury is generally associated with isolated cell loss that is characteristic of programmed cell death, apoptosis, rather than necrotizing forms of injury. In this regard, we have recently demonstrated that ethanol markedly sensitizes cells to apoptosis by suppressing the tyrosine kinase activity of the insulin-like growth factor I receptor (IGF-IR), a receptor that is key to the survival of many cell types. We hypothesize that ethanol-induced toxicity is modulated, at least in part, by expression and activation of the IGF-IR. Murine fibroblasts and neuroglial cell lines that exhibit tight growth factor regulation, IGF-I in particular, will be used as in vitro models to test the effect of ethanol on various modes of apoptosis initiation. The enhancement of apoptosis by ethanol will be correlated with IGF-IR expression and tyrosine auto-phosphorylation, and the expression and activation of key proximal signal mediators such as insulin-related substrate-1 (IRS-1), Src-homology 2/alpha-collagen (Shc), and phosphatidyl inositol 3-kinase. The effect of ethanol on IGF-IR and apoptosis will then be studied in rodent and chicken primary neuronal cell cultures and in vivo models. Specifically, we will analyze ethanol effects on the developing chicken, an established model for fetal alcohol syndrome, and relate neural crest cell death to the developmental dynamics of IGF-IR expression. Cell death will also be studied using implantable biodiffusion chamber in ethanol-intoxicated mice. Finally, we will use a novel functional expression cloning approach to identify IGF-I-inducible survival genes. We will study the effect of ethanol of the expression of these genes, and determine whether the overexpression of the genes desensitizes cells to the pro-apoptotic effect of ethanol.