熊果酸和齐墩果酸对心脏保护作用的研究进展

熊果酸和齐墩果酸通过抗氧化作用,抑制心脏脂质过氧化反应,提高心脏组织的抗氧化酶活性和非酶抗氧化物质水平,阻滞心肌细胞凋亡,产生心脏保护作用。熊果酸和齐墩果酸还可通过激活ATP敏感性钾通道并促进心房利钠肽合成和分泌,产生心脏保护作用。熊果酸和齐墩果酸也可通过抑制血管紧张素Ⅱ诱导心肌成纤维细胞增殖、转化生长因子-β_1表达、胶原合成和分泌,阻滞心肌纤维化形成。熊果酸和齐墩果酸的以上作用被认为是它们对抗异丙肾上腺素、乙醇、高血糖、高血压缺血、缺血再灌注引起心脏损伤的主要机制。熊果酸和齐墩果酸还具有免疫调节作用,能抑制T细胞核因子-κB核易位和T细胞活化,因此能防治实验性自身免疫性心肌炎和抑制机体对心脏移植物的排异反应。综述熊果酸和齐墩果酸对心脏保护作用的文献,并对其研究进展作了分析。     

肝脏细胞自噬在肝纤维化中的作用研究进展

肝纤维化是由于各种致病因子引起的肝脏结缔组织的异常增生。肝星状细胞的活化被普遍认为肝纤维化的中心环节,在肝纤维化过程中,自噬在不同的肝脏细胞中发挥着不同作用。一方面,在肝巨噬细胞、肝内皮细胞和肝实质细胞中,自噬可影响肝细胞炎症损伤反应抑制肝纤维化的发生;另一方面,在肝星状细胞中,自噬可影响氧化应激、内质网应激和脂质代谢等促进肝纤维化的发生。本文对肝脏不同细胞自噬在肝纤维化中的作用进行综述,为开发延缓和逆转肝纤维化的药物提供更完善的理论基础。     

氧化苦参碱抗慢性肝损伤的药理作用及其机制研究进展

氧化苦参碱具有抗高脂饮食性、CCl₄性、CCl₄/酒精性、二甲基亚硝胺性、半乳糖胺性、免疫性慢性肝损伤作用。氧化苦参碱是通过抗氧化、抗炎作用,减轻肝脏的氧化应激和炎症反应以及抑制成纤维细胞和肝星状细胞的活化以及细胞外基质生成,产生抗肝纤维化作用。氧化苦参碱还可通过促进胰岛素信号转导,改善胰岛素抵抗,抑制肝细胞吸收长链脂肪酸和脂肪酸合成并加速游离脂肪酸的β-氧化,产生抗脂肪肝作用。     

微小RNA-29在肝纤维化进程中的作用

微小RNA(miRNA)是一段含21~23个核苷酸的小的内源性非编码RNA,通过与靶基因mRNA的3'-UTR部分或完全互补结合抑制翻译或降解mRNA,进而调节细胞的生物学功能。肝星状细胞由静息态向活化态转化是肝纤维化发生发展的核心过程。近年研究发现,miRNA-29(miR-29)在静息态的肝星状细胞中高表达,且在肝纤维化进程中扮演重要角色,可调控参与肝纤维化形成的多种细胞因子和肝星状细胞的活化增殖等。本文针对近年来miR-29在肝星状细胞活化和肝纤维化进程中的作用进行综述。     

明知山路有艰险 越是艰险越向前——北京市药品监督管理局举行第三届登山健步走比赛

首都医科大学附属北京友谊医院实验中心主任贾继东的《肝星状细胞在肝纤维化发生中的作用及枉抗纤维化治疗中的意义》项目荣获2007年中华医学科技成果三等奖。该研究项目从体内外两方面观察肝星状细胞活化、增殖、凋亡，受体表达变化等对细胞外基质消长的影响，系统观察了肝星状细胞在肝纤维化发生中的作用，为抑制肝星状细胞在抗肝纤维化治疗中的作用提供了理论依据。     

姜黄素衍生物对原代大鼠肝星状细胞作用的体外研究

目的：观察姜黄素衍生物（Curc-OEG）抑制原代肝星状细胞（HSC）增殖、活化以及诱导其凋亡的作用,探讨其可能的作用机制。方法：采用IV型胶原酶、DNA酶消化SD雄性大鼠肝脏,percoll梯度离心得到纯化的肝星状细胞。细胞分离后1d分别加入0、6.25、12.5μg/mL的姜黄素衍生物,作用7d后用RT-PCR及Western blot检测细胞α-SMA、TGF-β1、Smad2的mRNA水平和蛋白表达量。活化的肝星状细胞在第14天分别加入0、6.25、12.5、25、50、75μg/mL的姜黄素衍生物,作用24h后RT-PCR检测凋亡基因Bax、Bcl-2的mRNA水平和纤维化相关基因TGF-β1、collagen I、NF-κB及TIMP-1的mRNA水平。结果：药物作用7d后,6.25μg/mL和12.5μg/mL浓度药物处理组与对照组相比,细胞数目分别减少了56%和86%。在12.5μg/mL浓度药物作用下,原代肝星状细胞α-SMA、TGF-β1及Smad2的mRNA表达水平分别下调83%、85%及75%,蛋白表达水平分别下调94%、92%及73%（P〈0.05）。25μg/mL浓度药物作用24h后,细胞凋亡明显。在50μg/mL浓度药物作用下,活化的肝星状细胞Bax的mRNA表达水平上调约2.3倍,Bcl-2的mRNA表达水平下调约5.6倍;TGF-β1、collagen I、NF-κB及TIMP-1的mRNA表达水平分别下调90%、83%、74%、65%（P〈0.05）。结论：姜黄素衍生物可以明显抑制原代肝星状细胞的增殖和活化,促进活化的肝星状细胞凋亡及减少细胞外基质的沉积。     

女贞子及其有效成分的保肝作用研究进展

女贞子具有保肝的药理作用,已经证实齐墩果酸、红景天苷、女贞子多糖等化合物是其保肝的有效成分。女贞子提取物及其有效成分能对抗多种化学性肝损伤、对抗免疫性或缺血再灌注性肝损伤以及抗肝纤维化,其中齐墩果酸的保肝作用被研究得最为广泛而深入;抗氧化应激、抗炎、抑制肝星状细胞增殖和活化、促进其凋亡以及肝细胞再生可能是它们共同的保肝机制。综述了女贞子粗提物、女贞子多糖和红景天苷保肝作用的研究进展。     

肝纤维化分子机制及治疗研究进展

肝纤维化由慢性肝炎造成,若治疗不及时将发展成为肝硬化、肝癌。目前,临床上尚无理想的治疗药物。随着肝纤维化分子机制逐渐得以阐明、基因技术不断发展,使肝纤维化的治疗成为可能。目前,肝纤维化治疗主要是通过抑制肝星状细胞（HSC）活化、增殖,抑制细胞外基质（ECM）的合成,促进ECM的降解,诱导活化HSC凋亡。本文就肝纤维化的分子机制和治疗进行综述,为以后的研究提供参考。     

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.     

三七皂苷抗肝纤维化作用的现状

肝纤维化是各种慢性肝病共同的病理基础，是慢性肝病发展到肝硬化、肝癌的必经途径。寻找有效的抗肝纤维化药物是近年研究的热点，其中对三七的研究也取得了很大进展。现综述近几年三七皂苷在保护肝细胞、抑制肝星状细胞活化、促进肝星状细胞凋亡、抑制细胞外基质的合成及促使其降解等方面的作用及可能机制，同时也阐述了三七皂苷在抗肝纤维化中的重要意义及应用前景。     

熊果酸抗实验性大鼠肝纤维化作用机制的研究

目的观察熊果酸对实验性大鼠肝纤维化的影响及可能的作用机理。方法将不同剂量的熊果酸10mg(kg/d)、20mg(kg/d)、40mg(kg/d)作用于二甲基亚硝胺(DMN)所致肝纤维化大鼠,在药物治疗4周后观察熊果酸对肝纤维化大鼠肝功能的影响;观察熊果酸对氧化指标SOD、MDA的影响;病理学方法观察熊果酸治疗后组织形态学的变化;RT-PCR方法检测熊果酸对MMP-1mRNA、TIMP-1mRNA表达变化。结果熊果酸可明显改善肝纤维化大鼠肝功能,并呈剂量依赖性;不同剂量熊果酸作用4周后能显著增加SOD表达,降低MDA表达;在病理学形态方面,熊果酸治疗组使肝组织结构不同程度改善;不同剂量熊果酸作用4周后RT-PCR方法检测治疗组MMP-1mRNA的表达较模型组相比明显升高,TIMP-1mRNA表达较模型组相比显著降低。结论熊果酸可明显改善肝纤维化大鼠肝功能,并呈剂量依赖性;熊果酸能显著增加SOD表达,降低MDA表达;熊果酸可上调MMP-1mRNA的表达,下调TIMP-1mRNA的表达;熊果酸治疗肝纤维化的作用机制可能与阻断氧化应激过程,抑制脂质过氧化,增加细胞外基质(ECM)的降解,减少ECM的沉积等机制有关。     

Hsian-tsao (Mesona procumbens Heml.) prevents against rat liver fibrosis induced by CCl4 via inhibition of hepatic stellate cells activation

In this study, the protective effect of extract of Hsian-tsao (Mesona procumbens) (EHT) against liver fibrogenesis in carbon tetrachloride (CCl₄)-injured rats was evaluated. The inhibitory effect of oleanolic acid (OA) and ursolic acid (UA), which are the active compounds in EHT, on the activation of hepatic stellate cells (HSC) was also determined. The results showed that EHT at a dosage of 1.2 g/kg of b.w. significantly reduced the liver injury induced by CCl₄ in rats. It also decreased the activity of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and the deposition of collagen in the liver. Oral administration of EHT reduced the levels of alpha-smooth muscle actin (α-SMA) and the activity of metalloproteinases (MMPs) in rats injured by treatment with CCl₄. In addition, we performed experiments with the rat hepatic stellate cell line HSC-T6 in which we induced the expression of MMP-2 and α-SMA with phorbol-12-myristate-13-acetate (PMA). Treating these cells with OA (20 μM) or UA (10 μM) caused a decrease in the levels of both proteins. Taken together, our data indicate that EHT can efficiently inhibit CCl₄-induced liver fibrosis in rats. EHT may therefore be a useful functional food for preventing liver fibrosis.     

熊果酸和齐墩果酸的血管药理作用研究进展

熊果酸和齐墩果酸能对抗氧化型低密度脂蛋白（ox-LDL）、C-反应蛋白、非酶糖基化终产物、高糖、H₂O₂、脂多糖对血管内皮细胞的损伤,其血管药理作用是多方面的。熊果酸和齐墩果酸能抑制血管平滑肌细胞增殖,也能对抗血清、ox-LDL、高糖、瘦蛋白诱导血管平滑肌细胞增殖,从而产生血管保护作用和改善血管功能;减轻糖尿病大鼠的血管损伤,减轻球囊导管损伤引起的血管狭窄,抑制静脉桥移植后的血管壁炎症反应和血管外膜成纤维细胞增殖并防止血管狭窄,以及防止多种实验性动脉粥样硬化模型动物的血管狭窄;对血管内皮细胞有抑制增殖作用,也有对抗伤害因子抑制增殖或促进增殖的双向作用,因此对血管生成也有双向调控作用,能抑制角膜、糖尿病动物视网膜及肿瘤组织内的血管新生;还有扩张血管,降低血管阻力,对正常的和多种高血压动物有显著的降压作用。     

Combined effects of a high-fat diet and chronic valproic acid treatment on hepatic steatosis and hepatotoxicity in rats

Aim： To investigate the potential interactive effects of a high-fat diet （HFD） and valproic acid （VPA） on hepatic steatosis and hepatotoxicity in rats. Methods： Male SD rats were orally administered VPA （100 or 500 mg.kgl.d1） combined with HFD or a standard diet for 8 weeks. Blood and liver samples were analyzed to determine lipid levels and hepatic function biomarkers using commercial kit assays. Low- molecular-weight compounds in serum, urine and bile samples were analyzed using a metabonomic approach based on GC/TOF-MS. Results： HFD alone induced extensive hepatocyte steatosis and edema in rats, while VPA alone did not cause significant liver lesions. VPA significantly aggravated HFD-induced accumulation of liver lipids, and caused additional spotty or piecemeal necrosis, accompanied by moderate infiltration of inflammatory cells in the liver. Metabonomic analysis of serum, urine and bile samples revealed that HFD significantly increased the levells of amino acids, free fatty acids （FFAs） and 3-hydroxy-butanoic acid, whereas VPA markedly decreased the levels of amino acids, FFAs and the intermediate products of the tricarboxylic acid cycle （TCA） compared with the control group. HFD aggravated VPA-induced inhibition on lipid and amino acid metabolism. Conclusion： HFD magnifies VPA-induced impairment of mitochondria113-oxidation of FFAs and TCA, thereby increases hepatic steatosis and hepatotoxicity. The results suggest the patients receiving VPA treatment should be advised to avoid eating HFD.     

GATA6抑制肝星状细胞活化在胆道闭锁肝纤维化中的研究进展

摘要：胆道闭锁（BA）以肝内外胆管进行性炎性阻塞和肝纤维化为特征,是引起婴幼儿梗阻性黄疸的常见原因之一。肝门空肠吻合术（Kasai术）是BA患儿的首选治疗手段。及时有效解除胆管炎性阻塞、遏制肝纤维化是延长或实现BA患儿自体肝生存的关键。GATA结合蛋白6（GATA6）具有调节转录活性的功能,可通过调控细胞增殖分化、协同上调铁调素的表达以及参与丝裂原活化蛋白激酶（MAPKs）依赖的信号通路等途径抑制肝星状细胞（HSCs）的活化,促进HSCs衰老,减轻肝纤维化,在BA肝损伤后肝修复过程中发挥一定的作用。该文就GATA6的功能特点、作用途径及其与BA肝纤维化之间的关系进行综述。     

Oridonin ameliorates carbon tetrachloride-induced liver fibrosis in mice through inhibition of the NLRP3 inflammasome

Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs) and accumulation of the extracellular matrix. There are limitations in the current therapies for liver fibrosis. Recently, oridonin was shown to induce apoptosis in HSCs. Thus, we aimed to determine the roles of oridonin in chronic liver injury and fibrosis. Liver fibrosis was induced by CCl₄ in mice injected intraperitoneally with oridonin for 6 weeks. The administration of oridonin significantly attenuated liver injury and reduced ALT levels. In addition, Sirius Red staining and the expression of α-smooth muscle actin (α-SMA) were significantly reduced by oridonin in murine livers with fibrosis. The expression of NLRP3, caspase-1, and IL-1β was downregulated with the oridonin treatment. Furthermore, the expression of F4/80 in liver tissues was also decreased by oridonin treatment. These results demonstrate that oridonin ameliorates chronic liver injury and fibrosis. Mechanically, oridonin may inhibit the activity of the NLRP3 inflammasome and inflammation in the liver. These results highlight the potential of oridonin as a therapeutic agent for liver fibrosis.     

转运体和代谢酶在胆汁淤积性肝损伤中的作用机制

胆汁淤积性肝损伤是临床常见的肝脏疾病,主要由体内胆汁酸平衡失调引起,其发病机制与胆汁酸转运体、合成酶和代谢酶的表达和功能变化直接相关。核受体通过调控胆汁酸转运体及代谢酶的表达,在胆汁淤积所致的肝损伤中发挥重要作用。对肝脏转运体和代谢酶在胆汁淤积性肝损伤中的作用及核受体对转运体和代谢酶的调控机制作一综述。     

Farnesoid X receptor contributes to oleanolic acid-induced cholestatic liver injury in mice

Farnesoid X receptor (FXR) is a nuclear receptor involved in the metabolism of bile acid. However, the molecular signaling of FXR in bile acid homeostasis in cholestatic drug-induced liver injury remains unclear. Oleanolic acid (OA), a natural triterpenoid, has been reported to produce evident cholestatic liver injury in mice after a long-term use. The present study aimed to investigate the role of FXR in OA-induced cholestatic liver injury in mice using C57BL/6J (WT) mice and FXR knockout (FXR^−/−) mice. The results showed that a significant alleviation in OA-induced cholestatic liver injury was observed in FXR^−/− mice as evidenced by decreases in serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase as well as reduced hepatocyte necrosis. UPLC-MS analysis of bile acids revealed that the contents of bile acids decreased significantly in liver and serum, while increased in the bile in FXR^−/− mice compared with in WT mice. In addition, the mRNA expressions of hepatic transporter Bsep, bile acid synthesis enzymes Bacs and Baat, and bile acids detoxifying enzymes Cyp3a11, Cyp2b10, Ephx1, Ugt1a1, and Ugt2b5 were increased in liver tissues of FXR^−/− mice treated with OA. Furthermore, the expression of membrane protein BSEP was significantly higher in livers of FXR^−/− mice compared with WT mice treated with OA. These results demonstrate that knockout of FXR may alleviate OA-induced cholestatic liver injury in mice by decreasing accumulation of bile acids both in the liver and serum, increasing the export of bile acids via the bile, and by upregulation of bile acids detoxification enzymes.     

Exendin-4 Improves Nonalcoholic Fatty Liver Disease by Regulating Glucose Transporter 4 Expression in ob/ob Mice

Exendin-4 (Ex-4), a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been known to reverse hepatic steatosis in ob/ob mice. Although many studies have evaluated molecular targets of Ex-4, its mechanism of action on hepatic steatosis and fibrosis has not fully been determined. In the liver, glucose transporter 4 (GLUT4) is mainly expressed in hepatocytes, endothelial cells and hepatic stellate cells (HSCs). In the present study, the effects of Ex-4 on GLUT4 expression were determined in the liver of ob/ob mice. Ob/ob mice were treated with Ex-4 for 10 weeks. Serum metabolic parameters, hepatic triglyceride levels, and liver tissues were evaluated for hepatic steatosis. The weights of the whole body and liver in ob/ob mice were reduced by long-term Ex-4 treatment. Serum metabolic parameters, hepatic steatosis, and hepatic fibrosis in ob/ob mice were reduced by Ex-4. Particularly, Ex-4 improved hepatic steatosis by enhancing GLUT4 via GLP-1R activation in ob/ob mice. Ex-4 treatment also inhibited hepatic fibrosis by decreasing expression of connective tissue growth factor in HSCs of ob/ob mice. Our data suggest that GLP-1 agonists exert a protective effect on hepatic steatosis and fibrosis in obesity and type 2 diabetes.