Mycophenolic acid induces apoptosis of hepatic stellate cells in an in vitro model of HCV.

Introduction: Hepatitis C virus (HCV) infection is an important risk factor for the development of liver fibrosis and progression to cirrhosis. Liver transplantation as terminal treatment option for liver disease requires life-long immunosuppression. However, immunomodulatory therapy may promote reinfection and renewed fibrogenesis.

Vitamin D counteracts fibrogenic TGF-β signalling in human hepatic stellate cells both receptor-dependently and independently.

Objective: Non-alcoholic fatty liver disease (NAFLD) is closely linked to obesity and constitutes part of the metabolic syndrome, which have been associated with low serum vitamin D (VD). Due to known crosstalk between VD and transforming growth factor (TGF)-β signalling, VD has been proposed as an antifibrotic treatment.

Design: We evaluated the association between VD, the vitamin D receptor (VDR) and liver fibrosis in primary human hepatic stellate cells (phHSC) and 106 morbidly obese patients with NAFLD.

Expression of apoptosis- and vitamin D pathway-related genes in hepatocellular carcinoma.

Background/aims: Hepatocellular carcinoma (HCC) is the sixth most common malignancy worldwide and therapeutic options are scarce. As they might represent future targets for cancer therapy, the expression of apoptosis-related genes in HCC is of particular interest. In this pilot study, we further examined apoptosis-related genes in human HCC and also focused on vitamin D signaling as this might be a regulator of HCC cell apoptosis.

Fetuin-A mRNA expression is elevated in NASH compared with NAFL patients.

Fetuin-A is a pro-inflammatory protein expressed by hepatocytes. Its course in morbidly obese patients with NAFLD (non-alcoholic fatty liver disease) following weight loss by BAS (bariatric surgery) has not been fully elucidated yet. In the present study, we prospectively examined the effects of weight loss on various metabolic factors at 4 weeks and 6 months after surgery.

Free fatty acids repress small heterodimer partner (SHP) activation and adiponectin counteracts bile acid-induced liver injury in superobese patients with nonalcoholic steatohepatitis.

Unlabelled: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in industrialized countries and may proceed to steatohepatitis (NASH). Apoptosis and free fatty acid (FFA)-induced lipotoxicity are important features of NASH pathogenesis. We have shown a hepatoprotective effect of adiponectin in steatotic livers of hepatitis C virus (HCV) patients and recent data links bile acid (BA) metabolism to the pathogenesis of NAFLD.

Vitamin D ameliorates stress ligand expression elicited by free fatty acids in the hepatic stellate cell line LX-2.

Background/aims: Hepatic stellate cells play an important role as the major source of fibrillar and non-fibrillar matrix proteins in the process of liver fibrosis. Natural killer cells have an anti-fibrotic effect through the killing of activated hepatic stellate cells. Major histocompatibility complex class I-related molecules, MICA and MICB, function as ligands for the NKG2D receptor and play an important role in hepatic stellate cells susceptibility to natural killer cells during hepatic inflammation.

Differential effects of factor IIa inhibitors on the endogenous thrombin potential.

Calibrated automated thrombin generation measurement in clotting plasma (endogenous thrombin potential, ETP) is being used increasingly to monitor the effects of anticoagulant drugs. Calibrated automated thrombography measures the concentration of thrombin in clotting plasma by monitoring the cleavage of a fluorogenic substrate (Z-Gly-Gly-Arg-7-amino-4-methylcoumarin) and comparing it with a constant known thrombin activity in a parallel nonclotting sample. This study compared the concentration-dependent effects of different factor IIa inhibitors on the ETP.

Inhibition of Na+/H+-exchanger with sabiporide attenuates the downregulation and uncoupling of the myocardial beta-adrenoceptor system in failing rabbit hearts.

Chronic heart failure (HF) is characterized by left ventricular (LV) structural remodeling, impaired function, increased circulating noradrenaline (NA) levels and impaired responsiveness of the myocardial beta-adrenoceptor (betaAR)-adenylyl cyclase (AC) system. In failing hearts, inhibition of the sodium/proton-exchanger (NHE)-1 attenuates LV remodeling and improves LV function. The mechanism(s) involved in these cardioprotective effects remain(s) unclear, but might involve effects on the impaired betaAR-AC system.

G-protein-coupled receptor kinase activity in human heart failure: effects of beta-adrenoceptor blockade.

Objectives: In human end-stage heart failure as well as in experimental animal models of heart failure, G-protein-coupled receptor kinase activity (GRK) is increased while beta-adrenoceptor responsiveness is diminished. In animal studies, beta-adrenoceptor blockers reverse the GRK-mediated desensitization and down-regulation of myocardial beta-adrenoceptors. The aim of this study was to investigate whether alterations in GRK activity are an early or late accompaniment of human heart failure and whether also in humans beta-adrenoceptor blocker treatment is able to influence myocardial GRK activity.

Unchanged G-protein-coupled receptor kinase activity in the aging human heart.

Objectives: We sought to find out whether G-protein-coupled receptor kinase (GRK) activity is also increased in the aging human heart.

Background: In the aging and failing human heart, cardiac beta-adrenoceptors (beta-AR) are desensitized. In heart failure (HF), an increase in cardiac GRK activity considerably contributes to this beta-AR desensitization.

Genotype-dependent time course of lymphocyte beta 2-adrenergic receptor down-regulation.

Background: Volunteers homozygous for Glu27 beta(2)-adrenergic receptor (beta(2)AR) polymorphism have delayed onset of agonist-induced desensitization of cardiac beta(2)AR responses.

Methods And Results: To determine whether this can also be demonstrated for Glu27Glu beta(2)AR natively expressed in circulating lymphocytes, we assessed the effects of 2 weeks of oral treatment with 3 x 5 mg/d terbutaline on lymphocyte beta(2)AR density (determined by [-]-[iodine 125]iodocyanopindolol binding) and responsiveness (assessed as [-]-isoproterenol hydrochloride [INN, isoprenaline] [1 nmol/L to 1 micromol/L]-induced lymphocyte cyclic adenosine monophosphate increases) in 23 healthy volunteers (13 with wild-type beta(2)AR [group A], 5 homozygous for Glu27 with Gly16Gly or Arg16Gly [group B], and 5 homozygous for Gly16 with Gln27Gln or Gln27Glu [group C]). Before terbutaline treatment, lymphocyte beta(2)AR density and isoproterenol-induced lymphocyte cyclic adenosine monophosphate accumulation were not significantly different in the genotype groups; 2 weeks of terbutaline treatment significantly decreased lymphocyte beta(2)AR density and responsiveness in the 3 genotype groups to a nearly identical extent, and no differences were observed.

Ventricular hypertrophy plus neurohumoral activation is necessary to alter the cardiac beta-adrenoceptor system in experimental heart failure.

Treatment of rats with monocrotaline (MCT) leads to pulmonary hypertension, right ventricular (RV) hypertrophy, and finally to RV heart failure. This is associated with characteristic changes in right ventricular beta-adrenoceptors (beta-AR), neuronal noradrenaline transporter (NAT) density and activity (uptake1), and G protein-coupled receptor kinase (GRK) activity. This study aimed to find out factors that determine beta-AR, uptake1, and GRK changes.