Anti-inflammatory and anti-oxidant effects of aloe vera in rats with non-alcoholic steatohepatitis

BACKGROUND Aloe vera exerts several biological activities, such as, anti-inflammatory, antioxidant, and antimicrobial effects. It was recently shown to reduce insulin resistance and triglyceride level. We hypothesized that aloe vera would have beneficial effects in alleviating non-alcoholic steatohepatitis(NASH) in rats.AIM To examine the therapeutic effects of aloe vera in NASH rats.METHODS All rats were randomly divided into 3 groups(n = 6 in each group). Rats in the control group were fed ad libitum with a standard diet for 8 wk. Rats in the NASH group were fed ad libitum with a high-fat high-fructose diet(HFHFD) for 8 wk. Rats in the aloe vera group were fed ad libitum with a HFHFD and aloe vera in dimethylsulfoxide(50 mg/kg) by gavage daily for 8 wk. Liver samples were collected at the end of the treatment period.RESULTS Hepatic malondialdehyde(MDA) levels increased significantly in the NASH group as compared with the control group(377 ± 77 nmol/mg vs 129 ± 51 nmol/mg protein, respectively, P 0.001). Glutathione(GSH) levels were significantly lower in the NASH group than the control group(9 ± 2 nmol/mg vs 24 ± 8 nmol/mg protein, respectively, P = 0.001). The expression of interleukin-18(IL-18), nuclear factor-kappa β, and caspase-3 increased, while peroxisome proliferator-activated receptor gamma decreased in the NASH group compared with the controls. Following aloe vera administration, MDA levels decreased(199 ± 35 nmol/mg protein) and GSH increased(18 ± 4 nmol/mg protein) markedly. Steatosis, hepatocyte ballooning, lobular inflammation and increased hepatocyte apoptosis were observed in the NASH group. Aloe vera treatment attenuated these changes in liver histology.CONCLUSION Aloe vera attenuated oxidative stress, hepatic inflammation and hepatocyte apoptosis, thus improving liver pathology in rats with NASH.     

Variations in peroxisomal catalase of neonatal rat hepatocyte subpopulations

Alcohol consumption during pregnancy is teratogenic and induces severe alterations in hepatocytes. In the hepatocyte peroxisomal system, ethanol is converted in the presence of H₂O₂ to acetaldehyde and water. Therefore, peroxisomal catalase also acts as an antioxidant defence mechanism by removing H₂O₂ and preventing the formation of hydroxyl radicals in the cell. Alterations in peroxisomal catalase after pre- and pre+postnatal alcohol exposure were investigated in the rat. The effect of pre- and postnatal exposure to ethanol on hepatocyte subpopulations was analysed in isolated hepatocytes originating from periportal, intermediate and perivenous zones. Analysis of catalase revealed that the total activity and content of this enzyme were higher in 12-day-old cells than in cells from newborns and that this increment was more pronounced in treated cells. In controls, the amount of peroxisomal catalase increased mainly in periportal cells, whereas alcohol exposure induced a significant increase in the catalase of perivenous hepatocytes. We conclude that pre- and postnatal alcohol exposure mainly affects the perivenous hepatocyte peroxisomes and that the increase in peroxisomal catalase could constitute a defence mechanism against free radical generation induced by alcohol exposure during the perinatal period.     

肝细胞生长因子在左肾动脉狭窄大鼠心血管中的表达及干预研究

目的　观察左肾动脉狭窄肾性高血压大鼠模型心肌和血管中肝细胞生长因子 (HGF)的表达 ,并观察缬沙坦和螺内酯对其表达的影响。方法　选用 6周龄SD大鼠 2 4只 ,制备左肾动脉狭窄肾性高血压模型 ,分为 4组 ,分别为手术组、假手术组、缬沙坦组、螺内酯组。治疗组分别用缬沙坦 3 0mg/kg·d-1、螺内酯 2 0mg/kg·d-1溶于饮水灌胃 ,1次 /d ,连续治疗 17周。用逆转录 聚合酶链反应 (RT PCR)法检测大鼠心肌和血管HGFmRNA水平。结果　 17周后 ,缬沙坦组和螺内酯组的心肌HGFmRNA/ β actinmRNA(1.17± 0 .0 8/ 0 .85± 0 .0 8)高于手术组 (0 .5 7± 0 .0 7) (P <0 .0 1) ,但低于假手术组 (1.3 5± 0 .0 9) (P均 <0 .0 1)。两治疗组肠系膜动脉HGFmRNA水平高于手术组 (P <0 .0 1) ,但低于假手术组 (P均 <0 .0 1)。结论　缬沙坦和螺内酯均能使左肾动脉狭窄肾性高血压大鼠心肌和血管中的HGF升高 ,同时伴有心肌和血管重塑的改善 ,说明HGF在左肾动脉狭窄肾性高血压大鼠的靶器官保护中起着重要作用     

高糖对大鼠系膜细胞肝细胞生长因子受体表达的影响及其机制研究

目的 观察高糖作用下大鼠系膜细胞(MsC)肝细胞生长因子（HGF）受体c-Met的表达，并探讨其机制和意义。 方法 用RT-PCR和Western 印迹方法检测高糖作用大鼠MsC的不同时间点（0、12、24、48、96 h）c-Met的表达。分别用光辉霉素A（mithramycin A）和SU11274抑制转录因子Sp1的DNA结合活性和阻断c-Met。用电泳迁移率改变实验(EMSA)观察Sp1与c-Met基因启动子的结合活性。以荧光探剂二氯双氢荧光素二乙酸酯(DCFH-DA)捕获细胞内活性氧。 结果 大鼠MsC的c-Met表达在高糖作用12、24和48 h都明显上升，96 h开始下降。光辉霉素A呈浓度依赖性抑制高糖作用下大鼠MsC的c-Met表达上调。大鼠MsC内Sp1与c-Met基因启动子的结合活性在高糖作用下明显增强。HGF及c-Met显著抑制高糖诱导的大鼠MsC内活性氧的增多。 结论 高糖作用下大鼠MsC的c-Met表达增强，其机制可能是通过Sp1介导。HGF-c-Met信号通路激活能抑制高糖所致大鼠MsC内的氧化应激反应。     

Hepatocyte isolation from pig livers after warm ischaemic injury

Abstract Hepatocyte cultures have been used extensively for a wide variety of physiological, pharmacological and experimental studies. The warm ischaemic period before isolation is kept to a minimum to achieve a high yield of cells isolated and a good viability for culture. We have recently introduced a new concept of liver resuscitation after warm ischaemia that is based on a 3-h reperfusion period with an improved perfusate and simultaneous dialysis. In this study, we applied the new technique for hepatocyte isolation from livers subjected to 80 min of complete ischaemia at 37 °C. Cell yield was improved by a resuscitating perfusion from 58% to 73% and viability from 39% to 76%.     

闭合型双循环生物人工肝支持系统治疗犬急性肝功能衰竭实验研究

目的探讨和评价闭合型双循环生物人工肝支持系统(CBC-BALSS)在治疗犬急性肝功能衰竭模型过程中的稳定性、安全性和有效性。方法建立犬急性肝功能衰竭模型(门腔分流联合胆总管离断),采用CBC-BALSS进行支持治疗。20只模型犬分为两组CBC-BALSS治疗组(n=11);无肝细胞CBC-BALSS对照组(n=9)。治疗时限6h。检测实验犬血氨、生化全套、凝血因子(FactorⅦ)、支/芳氨基酸(BCAA/AAA)、单乙基甘氨酸二甲苯胺(monoethylglycinexylidide,MEGX)和细胞循环路生化全套、肝细胞密度和数量。结果CBC-BALSS细胞回路细胞悬液总体积200ml,肝细胞的总数1×1010个、密度5×107/ml、活率98%左右。治疗中16只犬的生命体征平稳,在治疗30min内均出现一过性低血压;2只转流开始15min出现过敏反应;1只转流中因上消化道出血死亡;1只因穿刺部位出血死亡。模型治疗前血氨、ALT、TBil/DBil、白蛋白、FactorⅦ和BCAA/AAA分别达150mmol/L、400U/L、80/55mmol/L、35g/L、20%和1.6;CBC-BALSS治疗6h后,血氨、TBil/DBil下降均显著低于对照组;ALT存在下降趋势且在第6小时差异有统计学意义;白蛋白、FactorⅦ和BCAA/AAA在所有时段、组间差异均无统计学意义。在治疗1h和2h,MEGX差异有统计学意义,治疗组MEGX比对照组提前2h达最高点。治疗15~30min后,双循环路压力至115mmHg趋于平稳,且在±5mmHg波动。在治疗过程中,治疗组细胞循环路ALT显著性升高;组间细胞循环路TBil/DBil变化差异无统计学意义,而两组在各时间点均显著性升高;白蛋白变化无统计学意义。结论CBC-BALSS治疗犬急性肝功能衰竭过程中,安全、有效、稳定且代谢支持作用明显。     

参附注射液对单侧输尿管梗阻大鼠肾脏肝细胞生长因子表达的影响

目的：探讨单侧输尿管梗阻后大鼠肾间质纤维化发生过程中肝细胞生长因子（HGF）的表达及中药参附注射液对其的影响。方法：采用单侧输尿管结扎（UUO）制造梗阻性肾病模型，将56只大鼠随机分为对照组（假手术组）、手术组（UUO组）和治疗组（UUO＋参附），术后7d、14d观察肾组织病理改变，应用免疫组织化学方法检测肾组织中HGF的表达。结果：与对照组相比，手术组肾间质出现了明显的纤维化，HGF的表达在术后第7天明显增加，第14天较第7天减弱，与手术组相比，治疗组肾间质纤维化明显减轻，而且HGF的表达在术后第7天明显上调，第14天较第7天上调更明显，有统计学差异（P〈0．05）。结论：参附注射液可以上调肾组织HGF的表达，减轻肾小管一间质纤维化，发挥肾保护作用。     

重组肝细胞生长因子促进大鼠移植肝细胞的再生

目的探讨术后应用重组肝细胞生长因子(r HGF)对大鼠移植肝细胞再生的促进作用。方法采用改良“二袖套法”建立SD大鼠原位部分肝移植模型,受鼠分为实验组和对照组,术后经尾静脉分别给予r HGF和相同体积的生理盐水,2次/d。两个组分别在术后第1、2、4、7d时随机挑取5只大鼠处死,称取移植物湿重,采血检测血清丙氨酸转氨酶及白蛋白,流式细胞仪检测移植肝的增殖活性,免疫组织化学法检测移植肝Ki-67的表达情况。结果术后第1、2d,实验组移植物湿重较对照组同时间段明显增加;术后第4、7d,实验组血清丙氨酸转氨酶水平较对照组同时间段明显降低,而白蛋白水平较对照组同时间段明显增高;术后第2、4d,实验组的移植肝增殖指数和Ki-67表达较对照组高(P<0.05)。结论大鼠部分肝移植后使用r HGF能够明显促进移植肝细胞的再生。     

High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel

Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 10⁷ cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit.     

7例肝细胞体内移植患者临床护理需求的探讨

目的观察肝细胞体内移植术的有效性与安全性,探讨相应的护理需求。方法从自愿捐献者的肝脏内分离纯化肝细胞,制成悬液,经股动脉插管行脾动脉灌注移植,观察治疗后肝衰竭患者的肝功能恢复率、恢复时间、治疗不良反应及患者心态变化,针对不良反应及患者心理给予完善护理,建立肝细胞体内移植术护理规范。结果7例肝衰竭患者治疗后,4例临床治愈,有效率为57.1%,胆红素、凝血酶原活动度改善50%以上的发生时间约在术后4周。术后患者不同程度出现恶心、呕吐(57.1%),少量腹水(57.1%),肝性脑病(42.9%),发热(42.9%),穿刺点皮下血肿(28.6%),肺部真菌感染(14.3%)。术后71.4%的患者有焦虑情绪。经过相应的临床及心理护理,症状均有不同程度的改善。结论肝细胞体内移植可延长终末期肝病患者生存期,但病情明显改善所需时间约4周,防治肝性脑病、预防穿刺点皮下血肿及运用心理护理消除患者焦虑情绪是重要的护理需求。