POTENTIAL FETOPROTECTANTS FROM ETOH INDUCED STRESS

EtOH的摄入可导致各种自由基物质的产生。如果EtOH消耗量大且长期，体内器官开始恶化。一些器官损伤持续作为EtOH消耗的结果可能是由自由基的产生和随后的脂质过氧化（LPO）。现在理论上认为，LPO的广泛毒性作用可能有助于胎儿酒精综合征（FAS）的表达。水飞蓟素（SY），一种植物衍生的黄酮，已被确定为一种有效的抗氧化剂，目前在欧洲销售的商品名Legalon（R）作为一种保肝药物。我们已经进行了几项动物研究，SY对母亲和胎儿脑和肝组织中EtOH诱导的酶活性的保肝和护胎作用。我们现在想测试SY和其他四种抗氧化类黄酮的抗氧化作用;槲皮素，杨梅素，（+）-儿茶素，芹菜素对EtOH暴露的胎鼠脑和肝组织。根据研究结果预测了额外的黄酮类化合物的检测，其中证明这些黄酮类化合物也抑制EtOH诱导的自由基产生。为了比较抗氧化剂功效，还将测试N-乙酰半胱氨酸（NAC）和S-腺苷甲硫酮（SAM）。在先前的体外研究中已经证明，在EtOH中孵育胎鼠肝细胞（FRH）线粒体会增加氧化应激的指标。它进一步确定，在24小时暴露于乙醇之前和期间，用NAC或SAM处理FRH线粒体防止谷胱甘肽（GSH）的减少，恢复细胞复制，并缓和丙二醛（MDA）的产生。我们将该体外模型扩展到体内模型，以测试一种或所有类黄酮在使胎儿脑和肝组织中EtOH诱导的氧化应激正常化方面与NAC或SAM一样有效的一般假设。按照亨德森、Devi、Perez和Schencker（1995）中描述的程序，在妊娠第12、13和14天，每隔12小时，对母鼠进行6次EtOH插管。用于评估结局的相关指标包括：胎仔活力、胎仔体重、肝组织学、胎仔脑和肝组织谷胱甘肽水平、α生育酚水平、MDA水平和GGTP活性。 此外，为了继续我们实验室目前的研究，我们将建立平行组，其中大鼠幼崽将被饲养用于随后的行为测试。

The ingestion of EtOH can lead to the creation of a variety of free radical species. If EtOH consumption is heavy and chronic, organs within the body begin to deteriorate. Some of the organ damage sustained as a consequence of EtOH consumption might be caused by free radical generation and subsequent lipid peroxidation (LPO). It is now theorized that the pervasive and toxic effects of LPO may contribute to the expression of fetal alcohol syndrome (FAS). Silymarin (SY), a plant-derived flavone, has been identified as an effective antioxidant and is currently marketed in Europe wider the trade name Legalon(R) as a hepatoprotective medication. We have conducted several animal studies of the hepatoprotective and fetoprotective effects of SY against EtOH-induced enzyme activity in maternal and fetal brain and liver tissue. We now want to test the antioxidant effects of SY and four other antioxidant flavonoids; quercetin, myricetin, (+)-catechin, and apigenin on EtOH-exposed fetal rat brain and liver tissue. Testing of the additional bioflavonoid compounds is predicated on the results of studies in which it was demonstrated that these flavonoids also inhibited EtOH-induced free radical production. For purposes of comparison of antioxidant efficacy, N-acetylcysteine (NAC) and S- adenosylmethione (SAM) will also be tested. It has been demonstrated in previous in vitro studies that the incubation of fetal rat hepatocyte (FRH) mitochondria in EtOH increased indications of oxidative stress. It was further established that the treatment of the FRH mitochondria with NAC or SAM before and during the 24-hr exposure to EtOH prevented the decrease in glutathione (GSH), restored cell replication, and moderated malondialdehyde (MDA) production. We will extend this in vitro model to an in vivo model to test the general hypothesis that one or all of the flavonoids will be as effective as NAC or SAM at normalizing Et0H-induced oxidative stress in fetal brain and liver tissue. Dams will be intubated with EtOH six times at 12-hr. intervals over days 12, 13, and 14 of gestation following the procedures described in Henderson, Devi, Perez, & Schencker (1995). The dependent measures used to assess outcome will be: fetal viability, fetal weight, liver histology, fetal brain and liver tissue glutathione levels, alpha tocopherol levels, MDA levels, and GGTP activity. In addition, to continue with current studies in our lab, we will establish parallel groups in which rat pups will be raised for subsequent behavioral testing.