齐墩果酸对四氯化碳所致大鼠肝纤维损伤的保护作用

目的：研究齐墩果酸对四氯化碳所致大鼠肝纤维损伤的保护作用.方法：取健康雄性SD大鼠,随机分成4组,A组正常对照组,B组模型对照组,C组齐墩果酸低剂量组（30 mg·kg-1OA溶液）,D组齐墩果酸高剂量组（60 mg·kg-1OA溶液）.除正常对照组灌胃给予花生油外,其余各组都灌胃给予40%四氯化碳花生油溶液,进行肝纤维化的造模.造模同时,正常对照组和模型对照组灌胃等容0.25%CMC-Na溶液,齐墩果酸组按分组灌胃齐墩果酸0.25%CMC-Na溶液.每日一次,连续5周.末次给药后禁食24 h,取大鼠血和肝脏,进行血清肝功能指标检测（ALT、AST、ALB、TP、HA、LN、C-Ⅳ、PC-Ⅲ）和组织病理学观察.结果：齐墩果酸各剂量治疗组大鼠血清中ALT和AST含量明显低于模型对照组（P＜0.01）,Alb含量则显著高于模型组（P＜0.01）,而TP值两组间差异无统计学意义（P＞0.05）;模型组大鼠肝纤维化指标HA、LN、C-Ⅳ、PC-Ⅲ水平明显高于空白组（P＜0.01）,而齐墩果酸各剂量治疗组大鼠血清中这四个参数水平则明显低于模型对照组（P＜0.01）.病理组织学检查表明,用药各组肝纤维病理变化明显减轻.结论：齐墩果酸对实验性肝纤维化大鼠肝细胞有保护作用及抗肝纤维化作用.     

熊果酸和齐墩果酸的抗消化系肿瘤作用

熊果酸（UA）和齐墩果酸（OA）广泛存在于蔬菜、水果和中药材中,是生物活性广而又低毒的天然化合物。体外实验证明,UA和OA通过诱导癌细胞凋亡和坏死抑制胃癌、肠癌、肝癌等消化系肿瘤细胞增殖。UA和OA还有抗诱变、抗促癌和增强机体免疫作用。因此,UA和OA有望成为临床防治消化系肿瘤的药物。     

齐墩果酸大鼠肠吸收动力学

目的研究齐墩果酸在大鼠小肠的吸收动力学特征及吸收机制。方法采用大鼠在体肠灌流吸收实验模型,对齐墩果酸在大鼠体内的吸收机制及吸收动力学进行研究;使用紫外分光光度计测定大鼠在体肠循环液中酚红的浓度;采用HPLC-UV法测定循环液中齐墩果酸的浓度。结果齐墩果酸在小肠上段和下段的吸收速率常数分别为（0.140±0.007）、（0.134±0.014）h^-1。20.0、35.7、70.2 mg·L^-13个不同浓度循环液灌流中药物吸收速率常数分别为（0.141±0.026）、（0.165±0.036）、（0.145±0.014）h^-1。结论齐墩果酸在小肠中吸收良好,没有特定吸收部位;不同浓度对齐墩果酸在大鼠全肠道的吸收无显著影响,在20.0-70.2 mg·L^-1剂量与药物的吸收呈一级吸收动力学特征,吸收机制为被动扩散。齐墩果酸是难溶性药物,可以通过增加药物的溶出度,进而提高药物的生物利用度。     

熊果酸和齐墩果酸抗脑瘤作用的研究进展

熊果酸和齐墩果酸广泛存在于蔬菜、水果和中草药里,并被广泛研究。二者不仅同属五环三萜酸类化合物,又是同分异构体,药理作用几乎相同,都具有抗炎、抗变态反应、抗微生物、降血糖、调血脂、减肥、抗动脉粥样硬化、抗骨质疏松、保肝和免疫调节以及抗焦虑、抗抑郁、改善学习记忆等作用。熊果酸和齐墩果酸还具有广谱抗肿瘤作用,包括呼吸系肿瘤、消化系肿瘤、性器官肿瘤、皮肤癌和白血病等。综述熊果酸和齐墩果酸抗脑瘤作用及其机制的研究进展,为新药研发提供依据。     

齐墩果酸磷酸酯单钠的合成

本文首次报道了齐墩果酸磷酸酯单钠的合成。首先齐墩果酸与三氯氧磷作用生成其磷酸酯,然后转化成单钠盐。     

齐墩果酸对氧化损伤模型人脐静脉内皮细胞的保护作用

目的:研究齐墩果酸对氧化损伤模型人脐静脉内皮细胞(HUVECs)的保护作用。方法:分别以含10%胎牛血清DMEM高糖培养液[含氧化低密度脂蛋白(ox-LDL,质量浓度分别为0、25、50、100、200、400μg/ml)]培养HUVECs,CCK-8法检测细胞活性以筛选复制模型最适质量浓度。以0、10、20、40、60、80、100μmol/L齐墩果酸培养HUVECs,CCK-8法检测细胞活性以考察齐墩果酸试验最适浓度。以5、10、20、40μmol/L齐墩果酸作用于氧化损伤模型HUVECs(100μg/ml ox-LDL诱导),CCK-8法检测细胞活性,测定一氧化氮(NO)、一氧化氮合酶(NOS)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-PX)水平。结果:复制模型ox-LDL最适质量浓度为100μg/ml;齐墩果酸试验最适浓度范围为0⁴0μmol/L;5、10、20、40μmol/L齐墩果酸可增加氧化损伤模型HUVECs存活率,增强CAT、GSH-PX、NOS活性,增加NO含量。结论:齐墩果酸能够保护ox-LDL氧化损伤的HUVECs,其保护机制与增强CAT、GSH-PX、NOS抗氧化酶活性有关。     

齐墩果酸脂质体对顺铂所致小鼠肾氧化损伤的保护作用研究

目的 探讨齐墩果酸脂质体(OA-Lips)对顺铂所致小鼠肾组织氧化损伤的保护作用.方法 乙醇注入法制备OA-Lips.60只ICR小鼠随机分为对照组、模型组、阳性对照组和OA-Lips低、中、高剂量组,每组10只.OA-Lips各剂量组分别给予25、50和100 mg/kg OA-Lips灌胃,阳性对照组给予50 mg...     

齐墩果酸钠盐对大鼠化学性肝损伤的保护作用

目的 观察齐墩果酸钠盐对化学性损伤的肝细胞保护作用。方法 采用CCl4亚急性染毒建立化学性肝损伤大鼠模型,用齐墩果酸钠盐每天按三个剂量(3mg／kg、15mg／kg、30mg／kg)喂食大白鼠30天,测其血液生化指标并作组织病理学检查。结果 与对照组比较,齐墩果酸钠盐能显著降低大鼠血清的ALT和AST活性．肝脏组织结构病理损伤明显改善。结论 齐墩果酸钠盐对亚急性OCl4损伤的肝细胞具有保护作用。     

齐墩果酸药理作用研究进展

齐墩果酸（oleanolic acid，简称OA）是一种齐墩果烷型五环三萜类化合物，广泛分布于自然界，据不完全统计，OA以游离形式和（或）与糖结合形式广泛分布于大约60个科190种植物中，如在青叶胆全草、白花蛇舌草、女贞果实等植物中以游离形式存在或与糖结合成苷存在。OA具有消炎、增强免疫、抑制血小板降集、降糖、抗氧化和利尿作用等多方面的临床药理作用，还具有护肝、抗高血脂、抗动脉粥样硬化及抗肿瘤等生物活性。OA是治疗急性黄胆型肝炎和慢性病毒性肝炎比较理想的药物，且毒性低，不良反应少。     

齐墩果酸和熊果酸的抗炎及其抗变态反应

齐墩果酸(OA)和熊果酸(UA)是一同分异构体,近年来国内外对其在抗炎及抗变态反应方面作了广泛研究,证实其对Ⅰ~Ⅳ型变态反应和各种炎症动物模型均有抑制作用。文中就OA和UA在抗炎与抗变态反应以及作用机制方面的研究进展作一综述。     

Effects of the Amino Acid Constituents of Microcystin Variants on Cytotoxicity to Primary Cultured Rat Hepatocytes

Microcystins, which are cyclic heptapeptides produced by some cyanobacterial species from algal blooms, strongly inhibit serine/threonine protein phosphatase and are known as hepatotoxins. Microcystins have many structural variations, yet insufficient information is available on the differences in the cytotoxic potentials among the structural variants. In this study, the cytotoxicities of 16 microcystin variants at concentrations of 0.03–10 μg/mL to primary cultured rat hepatocytes were determined by measuring cellular ATP content, and subsequently determined by their 50% inhibitory concentration (IC₅₀). Differences in the amino acid constituents were associated with differences in cytotoxic potential. [d-Asp³, Z-Dhb⁷] microcystin-LR exhibited the strongest cytotoxicity at IC₅₀ of 0.053 μg/mL among the microcystin variants tested. Furthermore, [d-Asp³, Z-Dhb⁷] microcystin-HtyR was also highly cytotoxic. These results suggest that both d-Asp and Z-Dhb residues are important in determining the cytotoxic potential of microcystin variants.     

牛磺酸对原代培养大鼠肝细胞的促凋亡作用研究

目的探索分离培养原代正常大鼠肝细胞的条件和方法,研究牛磺酸对原代培养的正常大鼠肝细胞的促凋亡作用。方法使用经典的两步灌注法分离原代肝实质细胞后贴壁培养,记录细胞生长状况,台盼蓝拒染法测定细胞活率、绘制生长曲线。经用不同浓度的牛磺酸培养24 h后,用TUNEL法测定牛磺酸对原代培养大鼠肝细胞致凋亡作用,测定细胞凋亡率(AI)。结果两步灌注分离取得的肝细胞活率>70%,贴壁生长良好,从生长曲线可看出培养第3天进入对数生长期;TUNEL实验3个给药组AI分别为:3.71%,29.72%,42.56%。结论两步灌注法是一种细胞产量高,损伤小,纯度高的分离原代正常大鼠肝细胞的方法;高浓度的牛磺酸对体外培养肝细胞有一定致凋亡作用。     

Effect of Antihepatotoxic Agents Against Microcystin-LR Toxicity in Cultured Rat Hepatocytes

Primary cultures of adult rat hepatocytes were used to investigate the effects of two putative therapeutic agents, dithioerythritol and silymarin on microcystin-LR-induced hepatotoxicity. Cell injury was assessed by the extent of cellular [¹⁴C]adenine nucleotides and lactate dehydrogenase (LDH) release into the medium and the extent of hepatocyte detachment from monolayers. Microcystin-LR (1 µM) induced a significant release of both ¹⁴C-labeled nucleotides and LDH from hepatocytes as well as significant detachment of cells from monolayers. Although both dithioerythritol (0.63–5 mM) and silymarin (25–200 µM) reduced the amount of marker release and cell detachment from microcystin-LR-treated wells, silymarin provided significantly greater protection than dithioerythritol at one-tenth the concentration. Furthermore, silymarin and dithioerythritol treatment prevented morphological deformations and detachment of cells.     

可乐定对原代培养大鼠皮质神经元氧糖剥夺损伤的保护作用

目的：研究可乐定对原代培养大鼠皮质神经元氧糖剥夺( OGD)损伤的保护作用。方法取培养8 d的皮质神经元,分为正常对照组、模型对照组、可乐定(1.0,3.0,10.0μmol·L-1)预处理组。神经元氧糖剥脱损伤模型通过化学性缺氧、孵育液缺糖的方法建立。神经元损伤程度采用噻唑蓝( MTT)染色法和检测乳酸脱氢酶( LDH)的释放量来进行评价,观察预给予可乐定(1.0,3.0,10.0μmol·L-1)对神经元损伤的保护作用。结果显微镜下,正常对照组细胞密集,胞体饱满,边缘光滑,有较强折光性;神经元存活率(100.00±32.12)％,LDH释放比率(100.00±37.51)％。模型对照组细胞核固缩,细胞膜不完整,折光性差,MTT染色吸光度值明显降低,神经元存活率(53.61±7.62)％,LDH释放量显著增加,释放率为(166.07±9.65)％。可乐定(1.0,3.0,10μmol·L-1)预处理可明显逆转ODG损伤所致细胞形态的改变,剂量依耐性升高MTT染色吸光度值,神经元存活率分别为(67.53±10.54)％,(71.50±9.79)％和(87.48±5.29)％,同时可明显降低LDH的释放量,释放率分别为(136.45±25.72)％,(130.92±24.94)％和(121.63±32.68)％。结论可乐定对原代培养大鼠皮质神经元ODG损伤具有良好的保护作用。     

Effect of Rat Serum Lipoproteins on mRNA Levels and Amiodarone Metabolism by Cultured Primary Rat Hepatocytes

Hyperlipidemia can significantly increase amiodarone (AM) in vivo liver uptake and decrease its velocity of microsomal metabolism. Here, hepatocytes isolated from normolipidemic (NL) and hyperlipidemic rats were incubated with AM in the presence or absence of diluted NL or hyperlipidemic serum. The serum was added either as preincubation before drug, or concurrently with drug; incubations without rat serum were used as controls. The hepatocyte levels of mRNA for several proteins and enzymes were also measured. Disappearance of AM was seen up to 72 h. There was little difference between hepatocytes from NL or hyperlipidemic animals in intrinsic clearance (CL_int) of AM. The effect of hyperlipidemic rat serum, either before or with AM, was profound, causing a significant reduction in the CL_int. Reductions were seen in mRNA for cytochrome P450 1A1, 3A2, and 2D1, some transporters, and low‐density lipoprotein receptors after exposure of hepatocytes to lipoprotein‐rich sera. In conclusion, exposure of isolated hepatocytes to hyperlipidemic serum caused decreases in AM CL_int and lower mRNA levels for some proteins involved in the uptake and metabolism of AM. When coincubated with serum, an additional effect of increased binding to lipoproteins seemed to further contribute to a reduced CL of AM.     

Evaluation of the Uptake of Pravastatin by Perfused Rat Liver and Primary Cultured Rat Hepatocytes

Purpose. We have already demonstrated that the HMG-CoA reductase inhibitor, pravastatin is actively taken up by isolated rat hepatocytes via a multispecific anion transporter (Yamazaki et al., Am. J. Physiol. 264, G36-44, (1993)). We further attempted the quantitative evaluation of this uptake in different experimental systems. Methods. We have quantified the initial uptake of pravastatin by both primary cultured hepatocytes and by isolated perfused rat liver using the multiple indicator dilution (MID) method. Results. The permeability surface area product for the influx (PSinf) of pravastatin evaluated in MID study was comparable with those reported previously in isolated rat hepatocytes and in vivo. Furthermore, the highly concentrative uptake (influx clearance >> efflux clearance) of pravastatin was confirmed by kinetic analysis of the dilution curves obtained in the MID study. On the other hand, the uptake by primary cultured cells was significantly lower than that by isolated cells, and the ability of hepatocytes to take up pravastatin showed a decrease with time in culture (0-96 hr). The Vmax for uptake diminished with increasing time in culture, while no significant change was observed in both Km and nonspecific diffusion clearance. Conclusions. The MID method in isolated perfused liver which maintains the spatial and anatomical architecture can be used to quantitatively evaluate the initial uptake of pravastatin. Furthermore, the ability of hepatocytes to take up pravastatin is diminished in culture with time and this is caused by a decrease in Vmax.     

缬草提取物对胆汁酸代谢及肝损伤影响的实验研究

［摘要］目的探讨缬草提取物对高胆固醇 高脂肪 高糖膳食所致的胆汁 胆汁酸代谢变化及肝损害的影响。方法①大耳白种家兔24只,随机分为3组,每组8只。治疗组和对照组给予高胆固醇 高脂肪 高糖饲料。治疗组每天灌胃缬草提取物30 mg•kg 1,对照组灌胃等容积0.9%氯化钠溶液,正常组自由进食标准颗粒饲料,同时每天灌胃等容积0.9%氯化钠溶液。观察实验兔的血清丙氨酸氨基转移酶（ALT）、血总胆固醇（TC）及总胆汁酸（TBA）含量、胆汁的流量及其TC 磷脂 TBA含量、胆囊结石形成情况、肝组织学检查以及主动脉壁粥样斑块观察。②Wistar大鼠24只,随机分为3组,每组8只。治疗组和对照组给予高胆固醇 高脂肪 高糖饲料,正常组自由进食基础饲料。治疗组每天灌胃缬草提取物50 mg•kg 1,对照组则每天灌胃等容0.9%氯化钠溶液。观察血清TC、TBA及肝组织学检查。结果①家兔治疗组胆总管胆汁流量及固形物含量较对照组显著增加（P＜0.01）,胆汁中的TBA含量明显增加（P＜0.05）,血清TBA较对照组明显降低（P＜0.05）,胆囊内凝结物形成率明显低于对照组（P＜0.05）、肝损伤较对照组显著减轻。②大鼠治疗组血清TBA较对照组降低（P＜0.05）,肝损伤较对照组减轻。结论缬草提取物可以增加胆汁中TBA含量,提高TBA/TC结石形成,降低血清TBA浓度,明显减轻肝损伤。     

南沙参多糖对四氯化碳损伤原代培养大鼠肝细胞保护作用的研究

目的:探讨南沙参多糖(RAPS)对四氯化碳(CCl4)损伤原代培养大鼠肝细胞的保护作用及其机制。方法:通过原位灌流法分离大鼠肝细胞,培养36h后加入RAPS,同时造成CCl4损伤,分别于损伤24h和48h时检测培养液中丙二醛(MDA)的含量、丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)的活性,48h后用MTT法测定肝细胞存活率。结果:RAPS对CCl4引起的ALT、AST活力的升高有抑制作用,同时抑制MDA的产生及肝细胞损伤造成的SOD活性及GSH-PX活性的降低。而且能明显改善肝细胞存活率。结论:RAPS能有效抑制CCl4造成的原代培养大鼠肝细胞损伤,机制可能与其抗氧化作用有关。     

Protective Effects of Ferulic Acid on Deoxynivalenol-Induced Toxicity in IPEC-J2 Cells

Deoxynivalenol (DON), a mycotoxin that contaminates crops such as wheat and corn, can cause severe acute or chronic injury when ingested by animals or humans. This study investigated the protective effect of ferulic acid (FA), a polyphenolic substance, on alleviating the toxicity induced by DON (40 μM) in IPEC-J2 cells. The experiments results showed that FA not only alleviated the decrease in cell viability caused by DON (p < 0.05), but increased the level of superoxide dismutase (SOD) (p < 0.01), glutathione peroxidase (GSH-Px), (catalase) CAT and glutathione (GSH) (p < 0.05) through the nuclear factor erythroid 2-related factor 2 (Nrf2)-epoxy chloropropane Kelch sample related protein-1 (keap1) pathway, and then decreased the levels of intracellular oxidative stress. Additionally, FA could alleviate DON-induced inflammation through mitogen-activated protein kinases (MAPKs) and nuclear factor kappa-B (NF-κB) pathways, down-regulated the secretion of interleukin-6 (IL-6) (p < 0.0001), interleukin-8 (IL-8) (p < 0.05), interleukin-1β (IL-1β), interferon-γ (IFN-γ) and further attenuated the DON-induced intracellular apoptosis (10.7% to 6.84%) by regulating the expression of Bcl2-associated X protein (Bax) (p < 0.0001), B-cell lymphoma-2 (Bcl-2) (p < 0.0001), and caspase-3 (p < 0.0001). All these results indicate that FA exhibits a significantly protective effect against DON-induced toxicity.