prostaglandin-d2 and Liver-Cirrhosis

Topics: Animals; Biomarkers; Chagas Disease; Cytokines; DNA, Protozoan; Immunologic Factors; Liver; Liver Cirrhosis; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Parasite Load; PPAR gamma; Prostaglandin D2; Protozoan Proteins; Real-Time Polymerase Chain Reaction; Trypanosoma cruzi

15-Deoxy-Δ(12,14) -Prostaglandin J(2) (15d-PGJ(2) ), a natural peroxisome proliferator-activated receptor gamma (PPAR-γ) ligand, has been implicated as a new antiinflammatory compound with possible clinical applications. Based on this concept, this study was designed to evaluate the effects of 15d-PGJ(2) on bone marrow-derived monocyte/macrophage (BMM) migration, phagocytosis, and cytokine expression after liver injury using mouse models induced by cholestasis or carbon tetrachloride. Mice were lethally irradiated and received bone marrow transplants from enhanced green fluorescent protein transgenic mice. Our results showed that recruitment of BMM was significantly increased during chronic liver injury, and that 15d-PGJ(2) administration reduced BMM, but not neutrophil, dendritic, or T cell migration toward the damaged liver, involving reactive oxygen species generation and independently of PPAR-γ. Moreover, 15d-PGJ(2) inhibited the phagocytic activity of BMM and down-regulated inflammatory cytokine expression in vivo and in vitro. Accordingly, hepatic inflammation and fibrosis were strikingly ameliorated after 15d-PGJ(2) administration.. Our findings strongly suggest the antiinflammation and antifibrogenic potential of 15d-PGJ(2) in chronic liver diseases.

Topics: Analysis of Variance; Animals; Bone Marrow Transplantation; Cell Movement; Cell Proliferation; Cells, Cultured; Chronic Disease; Disease Models, Animal; Flow Cytometry; Fluorescent Antibody Technique; Liver Cirrhosis; Macrophages; Mice; Mice, Transgenic; Phagocytosis; Prostaglandin D2; Random Allocation; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction

Current knowledge confers a crucial role to connective tissue growth factor (CTGF/CCN2) in hepatic fibrogenesis. Hepatocytes are likely to be the major cellular source of CTGF in the liver in which CTGF is sensitively upregulated by TGF-beta. Recently, we demonstrated that the methylxanthine derivate caffeine leads to an upregulation of peroxisome proliferator activated receptor gamma (PPARgamma) expression in hepatocytes, thus sensitizing these cells to the well-known inhibitory effect of 15-deoxy-Delta(12,14)-prostaglandin J(2) (15-d-PGJ(2)) on CTGF expression. However, upregulation of the receptor alone is not sufficient per se; its physiological ligand 15-d-PGJ(2) is required to exert an inhibitory effect on transforming growth factor-beta (TGF-beta) target genes such as CTGF.. This study compared serum concentrations of 15-d-PGJ(2) in Caucasian patients with fibrotic liver diseases (n=289), Caucasian controls (n=136) and Caucasian non-liver disease (NLD) sick (n=307), as well as of Chinese patients with hepatocellular carcinoma (HCC) (n=43) and Chinese healthy controls (n=63) in order to characterize their suitability for therapeutic approaches with PPARgamma-inducing (i.e. CTGF inhibitory) drugs such as caffeine.. The presented data showed that Caucasian patients with ongoing hepatic fibrogenesis (mean 6.2+/-5.9 microg/L) displayed strikingly higher serum concentrations of 15-d-PGJ(2) than healthy probands (mean 2.3+/-1.0) and Caucasian patients with NLD (mean 2.7+/-1.4 microg/L). Similar results were found in Chinese patients with fully developed HCC (mean 1.3+/-0.7 microg/L) compared with Chinese healthy controls (mean 0.4+/-0.2 microg/L).. In conclusion, our data thus proposed an increased suitability of these patient groups for therapeutic approaches with drugs inducing PPARgamma expression, such as methylxanthine derivates.

Topics: Adult; Aged; Asian People; Caffeine; Connective Tissue Growth Factor; Female; Hepatocytes; Humans; Liver Cirrhosis; Male; Middle Aged; PPAR gamma; Prostaglandin D2; Up-Regulation; White People

Liver fibrosis can be induced by environmental chemicals or toxicants, and finally stimulates fibrogenic cytokines expression, such as transforming growth factor-beta (TGF-beta) and its downstream mediator connective tissue growth factor (CTGF). 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) is a metabolite of arachidonic acid, can act as a peroxisome proliferator-activated receptor gamma (PPARgamma) ligand, and function as either anti-inflammatory or inflammatory agents in different cell types. In this study, CTGF was detected in three human hepatoma cell lines, Hep3B, HepG2, and Huh-7, and it was up-regulated by TGF-beta. 15d-PGJ(2) significantly inhibited TGF-beta-induced CTGF protein and mRNA expressions, and promoter activity in hepatoma cells. 15d-PGJ(2) suppressed TGF-beta-induced Smad2 phosphorylation, however enhancing the phosphorylation of ERK, c-Jun N-terminal kinase (JNK), and p38 in TGF-beta-treated Hep3B cells. Other PPAR ligands like the PPARgamma agonist, troglitazone; the PPARalpha agonist, Wy-14643, and bezafibrate were also able to inhibit TGF-beta-induced CTGF. The results suggest that 15d-PGJ(2) inhibits TGF-beta-induced CTGF expression by inhibiting the phosphorylation of Smad2, which is independent of PPAR, and 15d-PGJ(2) might also act through a PPAR-dependent mechanism in human hepatoma cells. 15d-PGJ(2) might have a beneficent effect on prevention of liver fibrosis induced by environmental toxicants.

Topics: Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Survival; Connective Tissue Growth Factor; Fibrosis; Gene Expression; Hepatic Stellate Cells; Hepatocytes; Humans; Immunologic Factors; Liver Cirrhosis; Phosphorylation; Prostaglandin D2; RNA, Messenger; Smad2 Protein; Transforming Growth Factor beta; Up-Regulation

Delivery of apoptosis-inducing compounds to hepatic stellate cells (HSC) may be an effective strategy to reverse liver fibrosis. The aim of this study was therefore to examine the selective targeting of the apoptosis-inducing drug 15-deoxy-delta12,14-prostaglandin J2 (15dPGJ2) with two different HSC-carriers: human serum albumin modified with the sugar mannose-6-phosphate (M6PHSA) or albumin modified with PDGF-receptor recognizing peptides (pPBHSA).. After chemical conjugation of 15dPGJ2 to the carriers, the constructs displayed pharmacological activity and specific receptor-mediated binding to HSC in vitro. Unlike 15dPGJ2-pPBHSA, the cellular binding of 15dPGJ2-M6PHSA was reduced by a scavenger receptor antagonist. In vivo, both conjugates rapidly accumulated in fibrotic livers. Intrahepatic analysis revealed that 15dPGJ2-M6PHSA mainly accumulated in HSC, and to a lesser extent in Kupffer cells. 15dPGJ2-pPBHSA also predominantly accumulated in HSC with additional uptake in hepatocytes. Assessment of target receptors in human cirrhotic livers revealed that M6P/IGFII-receptor expression was present in fibrotic areas. PDGF-P receptor expression was abundantly expressed on human fibroblasts.. These studies show that 15dPGJ2 coupled to either M6PHSA or pPBHSA is specifically taken up by HSC and is highly effective within these cells. Both carriers differ with respect to receptor specificity, leading to differences in intrahepatic distribution. Nevertheless, both carriers can be used to deliver the apoptosis-inducing drug 15dPGJ2 to HSC in vivo.

Topics: Animals; Apoptosis; Apoptosis Regulatory Proteins; Drug Delivery Systems; Enzyme-Linked Immunosorbent Assay; Humans; Immunohistochemistry; Liver; Liver Cirrhosis; Liver Cirrhosis, Experimental; Male; Mannosephosphates; Peptides; Prostaglandin D2; Rats; Rats, Wistar; Receptor, Platelet-Derived Growth Factor beta; Reproducibility of Results; Serum Albumin

Hepatic myofibroblasts are central in liver fibrogenesis associated with chronic liver diseases. We previously showed that heme-oxygenase-1 (HO-1) displays antifibrogenic properties in human hepatic myofibroblasts. Here, we further investigated the mechanisms regulating HO-1 expression.. Expression of HO-1 was assayed in cultured human hepatic myofibroblasts by Northern and Western blot. Functional studies were also performed in cultured human hepatic myofibroblasts.. 15-Deoxy-Delta(12,14)-prostaglandin J2 (15-d-PGJ2) elicited inhibition of proliferation and of alpha1(I) collagen mRNA expression. These effects were reproduced by the glutathione depletor diethyl maleate and blunted by the glutathione precursor N-acetyl cysteine, indicating the involvement of oxidative stress. Two consecutive events mediated inhibition of proliferation and of alpha1(I) collagen mRNA expression by 15-d-PGJ2: (i) mild oxidative stress characterized by a transient GSH decrease and (ii) activation of p38 MAPK, resulting in increased HO-1 mRNA stability.. Our results provide new insights into the regulatory mechanisms governing HO-1 expression in human hepatic myofibroblasts and identify mild oxidative stress and p38 MAPK as two consecutive early signals promoting HO-1 induction that are crucial for its antifibrogenic properties, namely inhibition of growth and extracellular matrix gene expression.

Topics: Cell Proliferation; Cells, Cultured; Collagen Type I; Enzyme Induction; Gene Expression; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Humans; Liver; Liver Cirrhosis; MAP Kinase Signaling System; Membrane Proteins; Oxidation-Reduction; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Prostaglandin D2; RNA Stability; RNA, Messenger

Hepatic myofibroblasts play a key role in the development of liver fibrosis associated with chronic liver diseases. We have shown that oxidative stress is a messenger of 15-deoxy-delta-12,14-prostaglandin J2 (15-d-PGJ2) in human hepatic myofibroblasts. The aim of the present study was to investigate the role of a stress-inducible protein, heme oxygenase-1 (HO-1), in the action of 15-d-PGJ2.. Expression of HO-1 was characterized in biopsy specimens of normal human liver and active cirrhosis by immunohistochemistry, and in cultured human hepatic myofibroblasts by Northern and Western blot analysis. Functional studies also were performed in cultured human hepatic myofibroblasts.. Immunohistochemistry showed that in biopsy specimens from normal livers, HO-1 protein expression was restricted to Kupffer cells. Biopsy specimens from cirrhotic patients displayed HO-1 protein both in macrophages and in myofibroblasts within fibrotic septa. HO-1 messenger RNA (mRNA) and protein also were detected in cultured human hepatic myofibroblasts and increased in response to 15-d-PGJ2 in a time- and dose-dependent manner. Induction of HO-1 in human hepatic myofibroblasts mediated 2 major antifibrogenic properties of 15-d-PGJ2, namely, inhibition of proliferation and of procollagen I mRNA expression. These effects were ascribed to bilirubin, one of the products of HO-1-mediated heme degradation.. This study shows that HO-1 is expressed in human hepatic myofibroblasts and induced during chronic liver injury. Moreover, these data unravel HO-1 as a major antifibrogenic pathway.

Topics: Adult; Aged; Cell Division; Collagen Type I; Female; Fibroblasts; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Humans; Liver; Liver Cirrhosis; Male; Membrane Proteins; Middle Aged; Prostaglandin D2; RNA, Messenger

Proliferation and migration of hepatic stellate cells (HSCs) and expression of chemokines are involved in the pathogenesis of liver inflammation and fibrogenesis. Peroxisome proliferator-activated receptor (PPAR)-gamma is a receptor transcription factor that controls growth and differentiation in different tissues. We explored the effects of PPAR-gamma agonists on the biological actions of cultured human HSCs.. HSCs were isolated from normal human liver tissue and used in their myofibroblast-like phenotype or immediately after isolation. Activation of PPAR-gamma was induced with 15-deoxy-Delta(12, 14)-prostaglandin J(2) or with troglitazone.. PPAR-gamma agonists dose-dependently inhibited HSC proliferation and chemotaxis induced by platelet-derived growth factor. This effect was independent of changes in postreceptor signaling or expression of c-fos and c-myc and was associated with inhibition of cell cycle progression beyond the G(1) phase. Activation of PPAR-gamma also resulted in a complete inhibition of the expression of monocyte chemotactic protein 1 at the gene and protein levels. Comparison of quiescent and culture-activated HSCs revealed a marked decrease in PPAR-gamma expression in activated cells.. Activation of PPAR-gamma modulates profibrogenic and proinflammatory actions in HSCs. Reduced PPAR-gamma expression may contribute to confer an activated phenotype to HSCs.

Topics: Antineoplastic Agents; Biological Transport; Cell Division; Cell Movement; Cell Survival; Cells, Cultured; Chemokine CCL2; Chromans; Cytotoxins; Gene Expression; Hepatitis; Humans; Interleukin-1; Ligands; Liver; Liver Cirrhosis; Mitogen-Activated Protein Kinases; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Platelet-Derived Growth Factor; Prostaglandin D2; Proto-Oncogenes; Receptors, Cytoplasmic and Nuclear; RNA, Messenger; Thiazoles; Thiazolidinediones; Transcription Factor AP-1; Transcription Factors; Troglitazone; Tyrosine; Wound Healing