Potent antifibrotic activity of mTOR inhibitors sirolimus and everolimus but not of cyclosporine A and tacrolimus in experimental liver fibrosis.

Background & Aims: Recurrence of chronic hepatitis C and progressive fibrosis in liver transplants is frequent and impairs both graft and patient survival. Whether or not the choice of immunosuppression affects progression of fibrosis remains unclear. The aim of the present study was to compare the potential of the commonly used immunosuppressants to halt experimental liver fibrosis progression.

The production and composition of rat sebum is unaffected by 3 Gy gamma radiation.

Purpose: The aim of this work was to use metabolomics to evaluate sebum as a source of biomarkers for gamma-radiation exposure in the rat, and potentially in man. Proof of concept of radiation metabolomics was previously demonstrated in both mouse and rat urine, from the radiation dose- and time-dependent excretion of a set of urinary biomarkers.

Materials And Methods: Rats were gamma-irradiated (3 Gy) or sham irradiated and groups of rats were euthanised at 1 h or 24 h post-irradiation.

Pharmacological inhibition of integrin alphavbeta3 aggravates experimental liver fibrosis and suppresses hepatic angiogenesis.

Unlabelled: The vitronectin receptor integrin alphavbeta3 promotes angiogenesis by mediating migration and proliferation of endothelial cells, but also drives fibrogenic activation of hepatic stellate cells (HSCs) in vitro. Expecting antifibrotic synergism, we studied the effect of alphavbeta3 inhibition in two in vivo models of liver fibrogenesis. Liver fibrosis was induced in rats by way of bile duct ligation (BDL) for 6 weeks or thioacetamide (TAA) injections for 12 weeks.

Radiation metabolomics. 3. Biomarker discovery in the urine of gamma-irradiated rats using a simplified metabolomics protocol of gas chromatography-mass spectrometry combined with random forests machine learning algorithm.

Abstract Radiation metabolomics employing mass spectral technologies represents a plausible means of high-throughput minimally invasive radiation biodosimetry. A simplified metabolomics protocol is described that employs ubiquitous gas chromatography-mass spectrometry and open source software including random forests machine learning algorithm to uncover latent biomarkers of 3 Gy gamma radiation in rats. Urine was collected from six male Wistar rats and six sham-irradiated controls for 7 days, 4 prior to irradiation and 3 after irradiation.

Effects on hepatocellular carcinoma of doxorubicin-loaded immunoliposomes designed to target the VEGFR-2.

To maintain a tumour vasculature in proportion of the tumour growth, the endothelial cells proliferate and up-regulate the expression of the VEGF receptor 2 (VEGFR-2), whose expression is restricted to this cell type. This specificity implies that one therapeutically target the tumour endothelium. We investigated the use of immunoliposomes (IL), containing conjugated Fab' fragments of the monoclonal rat anti-VEGFR-2 antibody DC101 (DC101-IL) to cargo doxorubicin to the tumour endothelium.

Expression and activity of the cytochrome P450 2E1 in patients with nonalcoholic steatosis and steatohepatitis.

Background/aims: Nonalcoholic steatohepatitis (NASH) and nonalcoholic fatty liver (NAFL) have a different prognosis and should be dealt with differently. The pathogenesis of NASH implicates the overexpression of cytochrome P450 2E1 (CYP2E1). We investigated whether the noninvasive determination of CYP2E1 activity could replace a liver biopsy in order to differentiate NASH from NAFL.

Low-dose oral rapamycin treatment reduces fibrogenesis, improves liver function, and prolongs survival in rats with established liver cirrhosis.

Background/aims: Mammalian target of rapamycin (mTOR) signalling is central in the activation of hepatic stellate cells (HSCs), the key source of extracellular matrix (ECM) in fibrotic liver. We tested the therapeutic potential of the mTOR inhibitor rapamycin in advanced cirrhosis.

Methods: Cirrhosis was induced by bile duct-ligation (BDL) or thioacetamide injections (TAA).

Oral imatinib treatment reduces early fibrogenesis but does not prevent progression in the long term.

Background/aims: Transactivated hepatic stellate cells (HSCs) represent the key source of extra cellular matrix (ECM) in fibrotic liver. Imatinib, a potent inhibitor of the PDGF receptor tyrosine kinase, reduces HSC proliferation and fibrogenesis when treatment is initiated before fibrosis has developed. We tested the antifibrotic potential of imatinib in ongoing liver injury and in established fibrosis.

Endothelial nitric oxide synthase is not essential for the development of fibrosis and portal hypertension in bile duct ligated mice.

Background/aims: It is postulated that nitric oxide (NO) is responsible for the hyperdynamic circulation of portal hypertension. Therefore, we investigated induction of fibrosis and hyperdynamic circulation in endothelial NO synthase knock-out (KO) mice.

Methods: Fibrosis was induced by bile duct ligation.

Long-term treatment of bile duct-ligated rats with rapamycin (sirolimus) significantly attenuates liver fibrosis: analysis of the underlying mechanisms.

Rapamycin is an immunosuppressant with antiproliferative properties. We investigated whether rapamycin treatment of bile duct-ligated (BDL) rats is capable of inhibiting liver fibrosis and thereby affecting hemodynamics. Following BDL, rats were treated for 28 days with rapamycin (BDL SIR).

Effect of vascular endothelial growth factor on functional recovery after hepatectomy in lean and obese mice.

Background/aims: Liver regeneration is dependent upon coordinated proliferation of hepatocytes and endothelial cells. Vascular endothelial growth factor (VEGF) promotes angiogenesis. Hepatic steatosis delays regeneration and increases liver resection morbidity.

Extended preservation of rat liver graft by induction of heme oxygenase-1.

Livers can be preserved only for a short period without jeopardizing the transplantation outcome. Heat shock proteins (HSPs) protect against ischemia and reperfusion injury. We studied whether their induction and, in particular, the induction of heme oxygenase 1 (HO-1), improves transplantation survival after an extended time of cold storage.