Impact of liver transplantation on renal function of patients with congenital hepatic fibrosis associated with autosomal recessive polycystic kidney disease

Congenital hepatic fibrosis (CHF) is an uncommon autosomal recessive malformation. It may be associated with extrahepatic manifestations such as polycystic kidney disease. The main consequence is portal hypertension and bleeding from varices. Despite liver transplantation as a therapeutic option for this patient, long-term impact of liver transplantation on renal functions of patients with autosomal recessive polycystic kidney disease with associated liver disease is not well known. In this study, we aimed to analyze the patient's renal function after liver transplantation by creatinine clearance, glomerular filtration rate, and renal resistive indexes. Between March 1997 and September 2002, three of 50 orthotopic liver transplantation (OLT) were performed because of CHF associated with ARPKD at Ege University Organ Transplantation and Research Center. Baseline immunosuppression consisted of prednisone and cyclosporine A (CSA). The mean follow-up of the patients was 2.1 yr. Blood urea and creatinine levels were decreased after operation in all patients and remained within the normal range at the sixth and 12th month, whereas the level of the third patient were increased at the 18th month. RRI values of patients were not found different at the sixth month whereas, RRI values of patients were decreased at the 12th month and remained unchanged at the 18th month of follow-up. During the study period hypertension developed in one patient at the 16th month and resolved with antihypertensive treatment and decreasing dosage of CSA. Kidney function has remained satisfactory in all of the patients despite the use of cyclosporine. OLT can provide good survival in patients with CHF associated with ARPKD.     

Expression of AT1amRNA in rat hepatic stellate cells and its effects on cell growth collagen production

Activated hepatic stellate cells (HSCs) play important roles in hepatic fibrosis. Studies on HSCs activation in vitro have shown that this process is regulated by a wide variety of growth factors and cytokines。 Recent data indicate that Ang Ⅱ is responsible for the mechanisms of myocardial fibrosis and kidney fibrosis; but there are only few reports on hepatic fibrosis.     

Inhibitory effect of retroviral vector containing anti-sense Smad4 gene on Ito cell line, LI90

Background Transforming growth factor-β1 (TGF-β1) exerts strong fibrogenic potential in culture-activated HSCs. Smad4 is a key intracellular mediator for the transforming growth factor-β (TGF-β) superfamily of growth factors. The aim of this study was to assess the effects of the antisense Smad4 gene on Ito cell line, LI90.Methods The recombinant retroviral vector pLXSN-Smad4 was constructed by cloning the rat antisense Smad4 cDNA into the retroviral vector pLXSN. Retroviruses with or without the antisense gene were obtained by transfecting pLXSN-Smad4 and pLXSN vectors into PA317 cells. Human hepatic stellate cells (HSCs) LI90 were infected with these retroviruses followed by selection with G418. The expression of Smad4 was detected by Northern and Western blots. Cell biological characteristics, including cell growth curve, 3H-TdR and 3H-proline uptake by HSCs and the production of extracellular matrix were assessed.Results mRNA and protein expressions of Smad4 in LI90 cells transfected with retrovirus containing the antisense Smad4 gene were much lower than those in LI90 cells transfected with empty vector or parental LI90 cells. Cells hypoexpressing the Smad4 gene exhibited a slower rate of growth, a lower uptake of 3H-TdR and 3H-proline (P<0.01), and smaller production of th extracellular matrix, compared with parental LI90 cells and cells transfected with empty retrovirus.Conclusions The antisense Smad4 gene can suppress the expression of the Smad4 gene, reduce endogenous production of Smad4 mRNA and protein, block TGF-β1 signaling pathway, inhibit activation of Ito cells, obstruct the growth of Ito cells, decrease the production of the extracellular matrix （ECM）. Our results may provide a basis for the development of antifibrotic gene therapy.     

Immunomodulatory effect of oxymatrine on induced CCl4-hepatic fibrosis in rats

Liver fibrosis is a serious but reversible consequence of liver injuries. The treatment should include clearance of pathogeny, anti-fibrosis and heteropathy. As a potent ingredient extracted from traditional Chinese medicial herbs Sophora flavecientis and S. subprostratae ,oxymatrine contains a variety of alkaloids. Studies have shown that oxymatrine could relieve the inflammatory activity in liver tissue and has the effect of anti-fibrosis as well, whereas the therapeutic mechanism is not clear yet.The present study was designed to investigate the immunological mechanism of oxymatrine therapy for hepatic fibrosis.     

Liver metastases in germ cell cancer: defining a role for surgery after chemotherapy

OBJECTIVE: To review the clinical course and outcome of patients with germ cell cancer and liver metastases treated at one centre, as the presence of hepatic metastases, although rare, is a poor prognostic feature in germ cell cancer. PATIENTS AND METHODS: The case records of all patients with germ cell cancer and liver metastases at presentation, and treated with chemotherapy at a medical oncology unit between 1984 and 2001, were reviewed. The treatment regimens, tumour responses and patient outcome were recorded. RESULTS: Twenty-seven patients with germ cell cancer metastatic to the liver were identified. Complete biochemical and radiological responses were achieved in eight patients after initial chemotherapy and surgery for non-hepatic residual disease. Seven patients had only residual radiological hepatic abnormalities with normal tumour markers at the completion of initial treatment. There were no immediate hepatic resections and no further therapy was given. Serial computed tomography (CT) confirmed a progressive reduction in the size of hepatic lesions in six of seven patients. The persistence of residual hepatic abnormalities was not predictive of relapse, and overall survival of these patients (median survival 49 months, range 15-120) compared well with recent reports of such patients who have undergone hepatic resection. CONCLUSIONS: Conservative management with regular assessment by CT is an acceptable alternative to immediate hepatic resection for patients with isolated residual radiological hepatic abnormalities on completing first-line therapy for metastatic germ cell cancer, and does not adversely affect their survival.     

New support for branched-chain amino acid supplementation in advanced hepatic failure

Nutritional supplementation with branched-chain amino acids (BCAA) has been a topic of considerable debate for more than two decades. Several studies have demonstrated that supplementation with BCAA is associated with improvement of the catabolic state commonly seen in people with cirrhosis, whereas other studies have showed an improvement in portosystemic encephalopathy in patients with liver disease. Some studies have also shown there to be no benefit in BCAA supplementation in advanced cirrhosis. A recent large clinical trial showed that long-term BCAA supplementation may be useful in preventing progressive hepatic failure and improving liver function in some patients.     

Pancreatic stellate cell migration: role of the phosphatidylinositol 3-kinase(PI3-kinase) pathway

Pancreatic stellate cells (PSCs) are implicated as key mediators of pancreatic fibrogenesis and are found in increased numbers in areas of pancreatic injury. This increase in number may be due to increased local proliferation and/or migration of PSCs to affected areas from surrounding tissue. We have recently shown that PSCs can migrate and that this migration is stimulated by PDGF in a predominantly chemotactic manner [Gut 52 (2003) 677]. However, the signalling mechanisms responsible for PDGF-induced PSC migration are not known. Aims: (i) To determine whether PDGF-induced PSC migration is mediated by the PI3-kinase pathway. (ii) To investigate whether cell migration is influenced by cell proliferation and whether an interaction exists between the PI3-kinase pathway and the ERK1/2 pathway (known to mediate cell proliferation) in PSCs exposed to PDGF. Methods: (i) PI3-kinase activity was assessed by measuring the activation (phosphorylation) of its downstream substrate Akt in rat PSCs incubated with PDGF (10ng/mL) for 5min, 15min, 60min, and 24hr in the presence or absence of the specific PI3-kinase inhibitor wortmannin. (ii) The role of the PI3-kinase pathway in PSC migration was examined by assessing PSC migration through a porous membrane after exposure to PDGF in the presence and absence of wortmannin for 24hr. (iii) The relationship between migration and proliferation was assessed by examining migration of PSCs exposed to PDGF in the presence and absence of mitomycin C, an inhibitor of cell proliferation. (iv) The interaction between PI3-kinase and ERK1/2 was examined by incubation of PSCs with PDGF in the presence and absence of wortmannin, followed by assessment of ERK1/2 activation by western blot. Results: PDGF increased Akt activation in PSCs as early as at 5min of incubation and this increase was sustained for 24hr. Inhibition of PI3-kinase by wortmannin decreased basal as well as PDGF-induced migration and also inhibited ERK1/2 activation. Inhibition of PSC proliferation with mitomycin C significantly reduced (but did not abolish) basal and PDGF-induced PSC migration. Conclusions: (i) The PI3-kinase pathway is induced in PSCs after exposure to PDGF and this induction is sustained for at least 24hr. (ii) The PI3-kinase pathway plays a role in PDGF-induced PSC migration and is partially involved in mediating ERK1/2 activation. (iii) PSC migration is dependent, at least in part, on cell proliferation.     

Hepatic arterial catheterization combining interventional radiological and laparotomic approaches

BACKGROUND AND OBJECTIVES: This report describes a modified method of implanting a catheter-port system for hepatic arterial infusion chemotherapy (HAIC) that combines interventional radiological (IVR) and laparotomic approaches. METHODS AND RESULTS: In patients, scheduled for HAIC and laparotomic surgery, we now employ a modified method of implanting the catheter-port system. In our method, an IVR approach is used to implant the catheter-port, and arterial occlusions are primarily carried out using a laparotomic approach. Following celiac and superior mesenteric arteriographies, a tapered microcatheter with a side hole is inserted by a catheter exchange method. The catheter tip is advanced far into the gastroepiploic artery via the gastroduodenal artery (GDA). The side hole is located at the orifice of the proper hepatic artery, and its location is confirmed by injection of contrast media. The microcatheter is connected to the port, and the port is buried in the subcutaneous pocket. During the laparotomy stage, the GDA lumen and the catheter lumen are clipped, and the right gastric artery (RGA) and all small branches supplying the stomach, duodenum, and pancreas are ligated. Among the 13 patients successfully implanted with a port-catheter system using our combined approach, no patients had hepatic artery occlusion or occlusion of the catheter system. CONCLUSIONS: Initial results from a study of a new method of implanting a microcatheter-port system in the hepatic artery using combined IVR and laparotomic approaches suggest that this method may enable operators to avoid complicated selective coiling and may lower the incidence of hepatic artery occlusion in patients receiving long-term HAIC.     

The Complexities of Hepatic Drug Transport: Current Knowledge and Emerging Concepts

Recently, hepatic transport processes have been recognized as important determinants of drug disposition. Therefore, it is not surprising that characterization of the hepatic transport and biliary excretion properties of potential drug candidates is an important part of the drug development process. Such information also is useful in understanding alterations in the hepatobiliary disposition of compounds due to drug interactions or disease states. Basolateral transport systems are responsible for translocating molecules across the sinusoidal membrane, whereas active canalicular transport systems are responsible for the biliary excretion of drugs and metabolites. Several transport proteins involved in basolateral transport have been identified including the Na(+)-taurocholate co-transporting polypeptide [NTCP (SLC10A1)], organic anion transporting polypeptides [OATPs (SLCO family)], multidrug resistance-associated proteins [MRPs (ABCC family)], and organic anion and cation transporters [OATs, OCTs (SLC22A family)]. Canalicular transport is mediated predominantly via P-glycoprotein (ABCB1), MRP2 (ABCC2), the bile salt export pump [BSEP (ABCB11)], and the breast cancer resistance protein [BCRP (ABCG2)]. This review summarizes current knowledge regarding these hepatic basolateral and apical transport proteins in terms of substrate specificity, regulation by nuclear hormone receptors and intracellular signaling pathways, genetic differences, and role in drug interactions. Transport knockout models and other systems available for hepatobiliary transport studies also are discussed. This overview of hepatobiliary drug transport summarizes knowledge to date in this rapidly growing field and emphasizes the importance of understanding these fundamental processes in hepatic drug disposition.     

川芎嗪联用左旋精氨酸对缺血-再灌注损伤兔肝脏能量代谢的影响

目的:探讨川芎嗪(LGT)、左旋精氨酸(L-Arg)联合使用对肝缺血-再灌注损伤(HIRI)时肝细胞能量代谢的影响及其机制。方法:实验兔40只,建立肝缺血-再灌注模型后随机分4组:模型组,LGT组,L-Arg组和LGT+L-Arg组,每组10只。再灌注45 min时,分别检测肝组织内三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、一磷酸腺苷(AMP)含量、总腺苷酸量(TAN)、能荷(EC)、丙二醛浓度(MDA)、超氧化物歧化酶活性(SOD)、一氧化氮代谢产物(NO2-／NO3-)水平、血栓素B2(TXB2)、6-酮基-前列腺素F1α(6-keto-PGF1α)含量和TXB2／6-keto-PGF1α比值。结果:与模型组比较,LGT组、L-Arg组、LGT+L-Arg组肝组织内ATP、EC、NO2-／NO3-、6-keto-PGF1α含量及SOD活性均明显增高(P<0.05和P<0.01),MDA、TXB2含量及TXB2／6-keto-PGF1α比值均显著减少(P<0.05和P<0.01)。结论:LGT联用L-Arg可通过降低体内氧自由基水平、提高一氧化氮水平、纠正TXA2与PGI2的平衡,而改善缺血-再灌注损伤肝脏的能量代谢。