Characterization of a novel rat cholangiocarcinoma cell culture model-CGCCA

AIM:To characterize a culture model of rat CCA cells,which were derived from a transplantable TTA-induced CCA and designated as Chang Gung CCA(CGCCA).METHODS:The CGCCA cells were cultured at in vitro passage 12 times on a culture dish in DMEM medium.To measure the doubling time,103 cells were plated in a 96-well plate containing the growth medium.The cells were harvested 4 to 10 d after seeding,and astandard MTT assay was used to measure the growth.The phenotype of CACCA cell and xenograft was determined by...     

Protective effect of Pisonia aculeata on thioacetamide induced hepatotoxicity in rats

Objective

To evaluate the protective effect of Pisonia aculeata (P. aculeata) on thioacetamide induced hepatotoxicity in rats.

Methods

Male Wistar rats were administered 250 or 500 mg/kg p.o. of P. aculeata extract for 21 days and simultaneously administered thioacetamide (TAA) 50 mg/kg bw s.c. 1 h after the respective assigned treatments every 72 h. At the end of all experimental methods, all the animals were sacrificed by cervical decapitation. Blood samples were collected. Serum was separated and analyzed for various biochemical parameters.

Results

TAA induced a significant rise in aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), total bilirubin, gamma glutamate transpeptidase (GGTP), lipid peroxidase (LPO) with a reduction of total protein, superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and glutathione S-transferase (GST). Treatment of rats with different doses of plant extract (250 and 500 mg/kg) significantly (P<0.001) altered serum marker enzymes and antioxidant levels to near normal against TAA treated rats. The activity of the extract at a dose of 300 mg/kg was comparable to the standard drug, silymarin (50 mg/kg, p.o.).

Conclusions

It can be concluded that P. aculeata extract possesses a remarkable hepatoprotective and antioxidant activity against TAA induced hepatotoxicity. More research is required to derive an optimal therapeutic dose.     

桃核承气汤对大鼠肝性脑病模型干预治疗的分析

目的探讨桃核承气汤(去甘草)对硫代乙酰胺(TAA)诱导的大鼠肝性脑病的干预治疗作用。方法通过TAA腹腔注射诱导建立大鼠肝性脑病模型,观察桃核承气汤(去甘草)颗粒对肝性脑病的神经行为改变、神经病学测试、血清生化指标及肝脏和脑病理损伤的影响。结果本实验成功构建了大鼠肝性脑病模型。桃核承气汤(去甘草)颗粒低、中、高剂量均能不同程度地改善TAA引起的HE大鼠的神经反射情况,降低HE级别,降低血氨和生化指标指数以及使病理结果均呈现减轻的现象,其中以高剂量组为最佳(P0.05),效果与阳性药相近。结论桃核承气汤(去甘草)对TAA引起的大鼠肝性脑病有较好的预防治疗作用,本实验为该方剂的临床肝性脑病的使用提供了坚实的实验依据。     

急性肝性脑病大鼠脑水肿与脑水通道蛋白-4的相关性

目的 探讨水通道蛋白-4(AQP4)在急性肝衰竭肝性脑病与脑水肿的相关性。方法 采用硫代乙酰胺(TAA)腹腔注射制备急性肝衰竭肝性脑病大鼠模型。将健康雄性SD大鼠随机分为对照组8只和模型组24只,其中模型组根据造模后处死大鼠时间不同,分为24、48、60h组。观察大鼠一般情况,评估HE等级,测定血浆丙氨酸转氨酶、天冬氨酸转氨酶、总胆红素和血氨,观察肝组织病理学,检测脑含水量和脑组织AQP4（包括蛋白和mRNA）表达水平。结果 模型组大鼠表现出典型肝性脑病症状,随着造模后观察时间延长,HE等级进行性升高,肝脏生化和血氨水平较对照组显著升高(P＜0.05),肝组织病理变化与对照组差异有统计学意义。脑含水量和AQP4表达水平（包括蛋白和mRNA）明显高于对照组(P＜0.05),并且AQP4蛋白和mRNA表达水平分别与脑含水量呈正相关(r =0.536,P＜0.01;r=0.566,P=0.01)。结论 急性肝衰竭肝性脑病大鼠脑水通道蛋白-4(AQP4)表达与脑水肿密切相关,因此AQP4是急性肝衰竭肝性脑病脑水肿发生发展的重要分子机制之一。     

TAA诱导大鼠肝硬化模型及内毒素血症在肝硬化中作用的探讨

目的:建立稳定高效的硫代乙酰胺(thioacetamide,TAA)大鼠肝纤维化模型,探讨TAA诱导大鼠肝纤维化模型最佳初始浓度,观察大鼠肝纤维化模型建立成功后肝脏病理、血清ALT、内毒素变化。方法:SD雄性大鼠30只,随机分为两组,对照组15只、TAA组15只,对照组只给予饮用水,TAA组前6周在饮用水中加入0.03%TAA、后6周在饮用水中加入0.04%TAA造模,共12周。结果:TAA组肝硬化形成率95.8%,病死率4.2%;TAA组光镜下见正常肝小叶结构消失,形成大小不等的假小叶;TAA组血浆ALT水平及内毒素明显高于对照组,差异有统计学意义(P0.05)。结论:口服0.03%TAA作为诱导剂量,可成功诱导大鼠肝硬化,且肝硬化形成率高,该剂量大鼠死亡率低;且说明内毒素血症与大鼠肝硬化有一定关系。     

Effects of thioacetamide on pancreatic islet B-cell function

Thioacetamide (0.01–1.3 mM) fails to exert any significant immediate effect upon insulin release from rat isolated islets. However, when administered (4 μmol/g body wt) intraperitoneally 24 h before sacrifice, it reduced food intake and body weight and affected the secretory response of isolated islets to several secretagogues, despite unaltered insulin content of such islets. This coincided with a decrease in d-[U-¹⁴C]glucose oxidation, total islet calcium content and the ionized calcium content of secretory granules in islet B-cells, and changes in both ¹³³Ba and ⁴⁵Ca net uptake. Likewise, in islets prepared from thioacetamide-injected rats and prelabeled with ⁴⁵Ca before perifusion, the cationic and insulin secretory responses to d-glucose or gliclazide, but not to the association of Ba²⁺ and theophylline in the absence of extracellular Ca²⁺, often differed from that otherwise found in islets prepared from control rats. These findings are interpreted as indicative of an impaired capacity of Ca²⁺ sequestration by intracellular organelles in the islet B-cells of thioacetamide-treated rats.     

Protective Effects of Diallyl Sulfide against Thioacetamide-Induced Toxicity: A Possible Role of Cytochrome P450 2E1

Effects of diallyl sulfide (DAS) on thioacetamide-induced hepatotoxicity and immunotoxicity were investigated. When male Sprague-Dawley rats were treated orally with 100, 200 and 400 mg/kg of DAS in corn oil for three consecutive days, the activity of cytochrome P450 (CYP) 2E1-selective p-nitrophenol hydroxylase was dose-dependently suppressed. In addition, the activities of CYP 2B-selective benzyloxyresorufin O-debenzylase and pentoxyresorufin O-depentylase were significantly induced by the treatment with DAS. Western immunoblotting analyses also indicated the suppression of CYP 2E1 protein and/or the induction of CYP 2B protein by DAS. To investigate a possible role of metabolic activation by CYP enzymes in thioacetamide-induced hepatotoxicity, rats were pre-treated with 400 mg/kg of DAS for 3 days, followed by a single intraperitoneal treatment with 100 and 200 mg/kg of thioacetamide in saline for 24 hr. The activities of serum alanine aminotransferase and aspartate aminotransferase significantly elevated by thioacetamide were protected in DAS-pretreated animals. Likewise, the suppressed antibody response to sheep erythrocytes by thioacetamide was protected by DAS pretreatment in female BALB/c mice. Taken together, our present results indicated that thioacetamide might be activated to its toxic metabolite(s) by CYP 2E1, not by CYP 2B, in rats and mice.     

TAA可能诱发骨与关节病变

我国是世界上老年人口最多的国家,其数量占到了世界老年人口总量的五分之一。随着老年人口数量的持续增加,特别是肥胖老年人口的增多,骨与关节退行性疾病人群剧增。骨与关节退行性病变成为医学界关注的焦点之一,然而其临床治疗仍是难题,这个问题在进入老龄化的中国显得尤为重要。目前,很多研究退行性病的实验没有合适的动物模型,治疗骨与关节退行性变困难的原因之一是没有合适的动物模型进行药物的筛选。硫代乙酰胺(TAA)诱导的肝纤维化动物模型稳定且重复性较好,因此该药是制备肝纤维化动物模型的常用化学药剂,而本实验室在动物实验中发现TAA可以导致试验动物骨及关节的病变,也有不少文献报道TAA在诱发肝纤维化的同时可导致骨质的破坏,因此,我们推测可以通过TAA建立一种骨与关节退行性病变的动物模型。建立TAA诱发骨与关节退行性变动物模型不仅可以证实TAA导致骨与关节病变的因果关系,并能为研究骨与关节退行性病变的发病机制、临床治疗等提供研究平台;更能引发自然界中TAA的存在、转化形式、进入人体的途径、在人体特异蓄积部位以及对人体各器官的危害等重大社会环境问题的探讨。