Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 12 de 12
Filter
1.
Free Radic Biol Med ; 52(9): 1658-65, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22343419

ABSTRACT

The only currently recommended treatment for nonalcoholic fatty liver disease (NAFLD) is lifestyle modification. Preliminary studies of silybin showed beneficial effects on liver function. Realsil (RA) comprises the silybin phytosome complex (silybin plus phosphatidylcholine) coformulated with vitamin E. We report on a multicenter, phase III, double-blind clinical trial to assess RA in patients with histologically documented NAFLD. Patients were randomized 1:1 to RA or placebo (P) orally twice daily for 12 months. Prespecified primary outcomes were improvement over time in clinical condition, normalization of liver enzyme plasma levels, and improvement of ultrasonographic liver steatosis, homeostatic model assessment (HOMA), and quality of life. Secondary outcomes were improvement in liver histologic score and/or decrease in NAFLD score without worsening of fibrosis and plasma changes in cytokines, ferritin, and liver fibrosis markers. We treated 179 patients with NAFLD; 36 were also HCV positive. Forty-one patients were prematurely withdrawn and 138 patients analyzed per protocol (69 per group). Baseline patient characteristics were generally well balanced between groups, except for steatosis, portal infiltration, and fibrosis. Adverse events (AEs) were generally transient and included diarrhea, dysgeusia, and pruritus; no serious AEs were recorded. Patients receiving RA but not P showed significant improvements in liver enzyme plasma levels, HOMA, and liver histology. Body mass index normalized in 15% of RA patients (2.1% with P). HCV-positive patients in the RA but not the P group showed improvements in fibrogenesis markers. This is the first study to systematically assess silybin in NAFLD patients. Treatment with RA but not P for 12 months was associated with improvement in liver enzymes, insulin resistance, and liver histology, without increases in body weight. These findings warrant further investigation.


Subject(s)
Fatty Liver/drug therapy , Phosphatidylcholines/therapeutic use , Silymarin/therapeutic use , Vitamin E/therapeutic use , Body Mass Index , Humans , Phosphatidylcholines/administration & dosage , Romania , Silybin , Silymarin/administration & dosage , Vitamin E/administration & dosage
2.
Hepatology ; 54(3): 890-9, 2011 Sep 02.
Article in English | MEDLINE | ID: mdl-21618579

ABSTRACT

UNLABELLED: Cholangiocarcinoma (CCA) carries a severe prognosis because of its strong invasiveness and early metastasization. In several patients, otherwise eligible for surgical resection, micrometastasis are already present at the time of surgery. The mechanisms responsible for CCA invasiveness are unclear. S100A4, a member of the S100 family of small Ca(2+)-binding proteins, is expressed in mesenchymal cells, regulates cell motility in several cell types, and is expressed in some epithelial cancers. Thus, we aimed to study the role of S100A4 in CCA invasiveness and metastasization. The expression of S100A4 was studied by immunohistochemistry in 93 human liver samples of CCA patients undergoing surgical resection and correlated with metastases development (67 cases) and patient survival following surgery using log rank tests and multivariate analysis. S100A4 expression was studied in EGI-1 and TFK-1, human CCA cell lines with and without nuclear S100A4 expression, respectively. Metastatic properties of CCA cells were assessed by xenotransplantation in severe combined immunodeficiency (SCID) mice after transduction with lentiviral vectors encoding firefly luciferase gene. Proliferation, motility (wound healing), invasiveness (Boyden chamber), and metalloproteinases (MMPs) secretion were studied in CCA cells, with or without lentiviral silencing of S100A4. Nuclear expression of S100A4 by neoplastic ducts was a strong predictor of metastasization and reduced survival after resection (P < 0.01). EGI-1 CCA cells showed stronger metastatic properties than TFK-1 when xenotransplanted in SCID mice. S100A4-silenced EGI-1 cells showed significantly reduced motility, invasiveness, and MMP-9 secretion in vitro, without changes in cell proliferation. CONCLUSION: Nuclear S100A4 identifies a subset of CCA patients with a poor prognosis after surgical resection. Nuclear expression of S100A4 increases CCA cells invasiveness and metastasization, indicating that S100A4 may also represent a potential therapeutic target.


Subject(s)
Bile Duct Neoplasms/pathology , Bile Ducts, Intrahepatic , Cell Nucleus/chemistry , Cholangiocarcinoma/pathology , S100 Proteins/physiology , Aged , Animals , Apoptosis , Bile Duct Neoplasms/chemistry , Bile Duct Neoplasms/surgery , Cell Movement , Cell Proliferation , Cholangiocarcinoma/chemistry , Cholangiocarcinoma/surgery , Female , Humans , Male , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Mice , Middle Aged , Neoplasm Invasiveness , Neoplasm Metastasis , Prognosis , S100 Calcium-Binding Protein A4 , S100 Proteins/analysis
3.
Expert Opin Drug Saf ; 8(6): 695-707, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19832551

ABSTRACT

Inflammatory bowel diseases (IBDs) are a group of disorders characterised by chronic or relapsing inflammation within the gastrointestinal tract of variable severity. A chronic medication is often needed and management of fertile women is a crucial point because of the possible adverse effects associated with the administered drugs and the disease itself. The risk of pregnancy-related complications and the disease behaviour during pregnancy depends mainly on disease activity at time of conception. So, it is very important to plan the pregnancy and reach and maintain a clinical remission of the disease before conception. Drugs usually used in IBD treatment include 5- aminosalicylic acid compounds, corticosteroids, azathioprine and 6-mercaptopurine, cyclosporine A, mesalazine, and antibiotics such as metronidazole and ciprofloxacin. Management of IBD in pregnancy at present is not standardised or supported by strong evidence. In this report, we summarise the available data, mainly derived from retrospective and case-control studies, about IBD management in pregnancy, focusing mostly on the safety of drugs during gestation and peripartum.


Subject(s)
Inflammatory Bowel Diseases/drug therapy , Lactation/physiology , Adult , Animals , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/therapeutic use , Anti-Inflammatory Agents/adverse effects , Anti-Inflammatory Agents/therapeutic use , Antidiarrheals/adverse effects , Antidiarrheals/therapeutic use , Biological Therapy/adverse effects , Female , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Postpartum Period , Pregnancy , Pregnancy Complications/drug therapy , Probiotics/adverse effects , Probiotics/therapeutic use
4.
Gastrointest Endosc ; 70(2): 212-24, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19409558

ABSTRACT

BACKGROUND: Advances in medical practice in recent decades have influenced the etiology and management of acute upper-GI bleeding (UGIB), but their impact on the incidence and mortality is unclear. OBJECTIVE: To analyze the time trends of UGIB in 2 different management eras. DESIGN: Prospective observational study. SETTING: General university-affiliated hospital. PATIENTS AND INTERVENTIONS: A total of 587 patients who presented with UGIB during the 1983-to-1985 period were compared with 539 patient in the 2002-to-2004 period. RESULTS: The overall incidence of UGIB decreased from 112.5 to 89.8 per 100,000/y, which corresponds to a 35.5% decrease after adjustment for age (95% CI, 24.2%-46.8%). The age standardized incidence of ulcer bleeding decreased by 41.6% (95% CI, 27.2%-56%); the decrease occurred only in people younger than 70 years of age. The rate of history of peptic ulcer disease decreased from 32.7% in the 1983-to-1985 period versus 19.5% in the 2002-to-2004 period (P < .001). The mean age increased from 61.0 to 68.7 years (P < .001), and the male:female ratio decreased from 2.7 to 1.8 (P = .002). The comorbidities increased from 69% to 75% (P = .01), the use of nonsteroidal anti-inflammatory drugs from 40.0% to 46.4% (P = .03), and the cases of bleeding occurring during hospitalization from 10.4% to 17.1% (P < .001). In the 1983-to-1985 cohort, the endoscopy was solely diagnostic, and antisecretory therapy consisted of H2-antagonists drugs. In the second period, 39.3% of patients underwent endoscopic therapy, whereas proton pump inhibitors were administered in 47%. Rebleeding rates decreased from 32.5% to 7.4% (P < .001) and surgery from 10.2% to 2.0% (P < .001). Overall mortality decreased from 17.1 to 8.2 per 100,000/y, which corresponded to a 60.8% decrease after adjustment for age (95% CI, 46.5%-75.1%). The age standardized mortality rate for ulcer bleeding decreased by 56.5% (95% CI, 41.9%-71.1%). LIMITATIONS: A single-center study and a potential lack of generalizability. CONCLUSIONS: From the 1983-to-1985 period to the 2002-to-2004 period, major changes occurred in the incidence of UGIB, features of patients, management, and outcomes. The incidence and mortality of UGIB overall and ulcer bleeding decreased significantly, and the decline of incidence occurred only in patients younger than 70 years old.


Subject(s)
Gastrointestinal Hemorrhage/epidemiology , Acute Disease , Aged , Endoscopy, Gastrointestinal , Female , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/therapy , Humans , Incidence , Male , Middle Aged , Prospective Studies , Time Factors
5.
Hepatology ; 47(2): 719-28, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18157837

ABSTRACT

UNLABELLED: Intrahepatic bile ducts maintain a close anatomical relationship with hepatic arteries. During liver ontogenesis, the development of the hepatic artery appears to be modulated by unknown signals originating from the bile duct. Given the capability of cholangiocytes to produce angiogenic growth factors and influence peribiliary vascularization, we studied the immunohistochemical expression of vascular endothelial growth factor (VEGF), angiopoietin-1, angiopoietin-2, and their cognate receptors (VEGFR-1, VEGFR-2, Tie-2) in fetal human livers at different gestational ages and in mice characterized by defective biliary morphogenesis (Hnf6(-/-)). The results showed that throughout the different developmental stages, VEGF was expressed by developing bile ducts and angiopoietin-1 by hepatoblasts, whereas their cognate receptors were variably expressed by vascular cells according to the different maturational stages. Precursors of endothelial and mural cells expressed VEGFR-2 and Tie-2, respectively. In immature hepatic arteries, endothelial cells expressed VEGFR-1, whereas mural cells expressed both Tie-2 and Angiopoietin-2. In mature hepatic arteries, endothelial cells expressed Tie-2 along with VEGFR-1. In early postnatal Hnf6(-/-) mice, VEGF-expressing ductal plates failed to incorporate into the portal mesenchyma, resulting in severely altered arterial vasculogenesis. CONCLUSION: The reciprocal expression of angiogenic growth factors and receptors during development supports their involvement in the cross talk between liver epithelial cells and the portal vasculature. Cholangiocytes generate a VEGF gradient that is crucial during the migratory stage, when it determines arterial vasculogenesis in their vicinity, whereas angiopoietin-1 signaling from hepatoblasts contributes to the remodeling of the hepatic artery necessary to meet the demands of the developing epithelium.


Subject(s)
Epithelial Cells/physiology , Growth Substances/physiology , Hepatic Artery/cytology , Hepatic Artery/physiology , Liver/cytology , Liver/embryology , Neovascularization, Physiologic , Animals , Bile Ducts/embryology , Gestational Age , Hepatocyte Nuclear Factor 6/deficiency , Humans , Mice , Mice, Knockout , Portal System/embryology , Portal System/pathology , Portal System/physiology
6.
Gastroenterology ; 133(5): 1603-13, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17983806

ABSTRACT

BACKGROUND & AIMS: Cholangiopathies are characterized by impaired cholangiocyte secretion. Ursodeoxycholic acid (UDCA) is widely used for cholangiopathy treatment, but its effects on cholangiocyte secretory functions remain unclear and are the subject of this study. METHODS: Polarized mouse cholangiocytes in tubular (isolated bile-duct units [IBDU]) or monolayer configuration were obtained from wild-type (WT) and B6-129-Cftr(tm1Kth) and Cftr(tm1Unc) mice that are defective in CFTR, an adenosine 3',5'-cyclic monophosphate (cAMP)-stimulated Cl(-) channel expressed in cholangiocytes. Fluid secretion was assessed by video-optical planimetry, Cl(-) and Ca(2+) efflux by microfluorimetry (6-methoxy-N-ethylquinolinium chloride, fura-2, and fluo-4), adenosine triphosphate (ATP) secretion by luciferin-luciferase assay, and protein kinase C (PKC) by Western blot. RESULTS: UDCA stimulated fluid secretion and Cl(-) efflux in WT-IBDU but not in CFTR-KO-IBDU or in WT-IBDU exposed to CFTR inhibitors. UDCA did not affect intracellular cAMP levels but increased [Ca(2+)]i in WT and not in CFTR-KO cholangiocytes. UDCA stimulated apical ATP secretion in WT but not in CFTR-KO cholangiocytes. UDCA-stimulated [Ca(2+)]i increase was inhibited by suramin, a purinergic 2Y-receptor inhibitor. UDCA stimulated the translocation of PKC-alpha and PKC-epsilon to the plasma membrane. UDCA-stimulated secretion was inhibited by 2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid and by phospholipase C and PKC inhibitors. UDCA increased ATP output in isolated perfused livers from WT but not from CFTR-KO mice. CONCLUSIONS: Our data indicate that UDCA stimulates a CFTR-dependent apical ATP release in cholangiocytes. Secreted ATP activates purinergic 2Y receptors, and, through [Ca(2+)]i increase and PKC activation stimulates Cl(-) efflux and fluid secretion. These data support the concept that CFTR plays a role in modulating purinergic signaling in secretory epithelia and suggest a novel mechanism explaining the choleretic effect of UDCA.


Subject(s)
Adenosine Triphosphate/metabolism , Bile Ducts, Intrahepatic/metabolism , Cholagogues and Choleretics/pharmacology , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Ursodeoxycholic Acid/pharmacology , Animals , Bile Ducts, Intrahepatic/pathology , Calcium/metabolism , Calcium Signaling/physiology , Cyclic AMP/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/drug effects , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Mice , Mice, Knockout , Protein Kinase C/metabolism , Wnt Proteins/metabolism
7.
Am J Pathol ; 171(2): 641-53, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17600123

ABSTRACT

Patients with Alagille syndrome (AGS), a genetic disorder of Notch signaling, suffer from severe ductopenia and cholestasis, but progression to biliary cirrhosis is rare. Instead, in biliary atresia (BA) severe cholestasis is associated with a pronounced "ductular reaction" and rapid progression to biliary cirrhosis. Given the role of Notch in biliary development, we hypothesized that defective Notch signaling would influence the reparative mechanisms in cholestatic cholangiopathies. Thus we compared phenotype and relative abundance of the epithelial components of the hepatic reparative complex in AGS (n = 10) and BA (n = 30) using immunohistochemistry and computer-assisted morphometry. BA was characterized by an increase in reactive ductular and hepatic progenitor cells, whereas in AGS, a striking increase in intermediate hepatobiliary cells contrasted with the near absence of reactive ductular cells and hepatic progenitor cells. Hepatocellular mitoinhibition index (p21(waf1)/Ki67) was similar in AGS and BA. Fibrosis was more severe in BA, where portal septa thickness positively correlated with reactive ductular cells and hepatic progenitor cells. AGS hepatobiliary cells failed to express hepatic nuclear factor (HNF) 1beta, a biliary-specific transcription factor. These data indicate that Notch signaling plays a role in liver repair mechanisms in postnatal life: its defect results in absent reactive ductular cells and accumulation of hepatobiliary cells lacking HNF1beta, thus being unable to switch to a biliary phenotype.


Subject(s)
Alagille Syndrome/pathology , Biliary Atresia/pathology , Liver Regeneration , Liver/pathology , Receptors, Notch/physiology , Adolescent , Adult , Alagille Syndrome/metabolism , Biliary Atresia/metabolism , Biliary Atresia/surgery , Child , Child, Preschool , Cyclin-Dependent Kinase Inhibitor p21/analysis , Female , Hepatocyte Nuclear Factor 1-beta/analysis , Hepatocytes/chemistry , Hepatocytes/pathology , Humans , Immunohistochemistry , Infant , Keratin-19/analysis , Keratin-7/analysis , Ki-67 Antigen/analysis , Liver/chemistry , Liver/physiopathology , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Liver Transplantation , Male , Middle Aged , Severity of Illness Index , Signal Transduction/physiology
8.
Hepatology ; 43(5): 1001-12, 2006 May.
Article in English | MEDLINE | ID: mdl-16628643

ABSTRACT

Liver involvement in autosomal dominant polycystic kidney disease (ADPKD) is characterized by altered remodeling of the embryonic ductal plate (DP) with presence of biliary cysts and aberrant portal vasculature. The genetic defect causing ADPKD has been identified, but mechanisms of liver cyst growth remain uncertain. To investigate the possible role of angiogenic mechanisms, we have studied the immunohistochemical expression of vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and their receptors (VEGFR-1, VEGFR-2, Tie-2) in ADPKD, Caroli's disease, normal and fetal livers. In ADPKD and control livers Ang-1 and Ang-2 gene expression was studied by real-time-PCR. Effects of VEGF on cholangiocyte proliferation were studied by PCNA Western Blot in isolated rat cholangiocytes and by MTS assay in cultured cholangiocytes isolated from ADPKD patients and from an ADPKD mouse model (Pkd2(WS25/-)). Cholangiocytes were strongly positive for VEGF, VEGFR-1, VEGFR-2 and Ang-2 in ADPKD and Caroli, and also for Ang-1 and Tie-2 in ADPKD, similar to fetal ductal plate cells. VEGF stimulated proliferation in both normal and ADPKD cholangiocytes, but the effect was particularly evident in the latter. Ang-1 alone had no effect, but was synergic to VEGF. VEGF expression on cholangiocytes positively correlated with microvascular density. In conclusion, consistent with the immature phenotype of the cystic epithelium, expression of VEGF, VEGFRs, Ang-1 and Tie-2 is strongly upregulated in cholangiocytes from polycystic liver diseases. VEGF and Ang-1 have autocrine proliferative effect on cholangiocyte growth and paracrine effect on portal vasculature, thus promoting the growth of the cysts and their vascular supply. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).


Subject(s)
Angiogenic Proteins/biosynthesis , Bile Ducts/cytology , Bile Ducts/metabolism , Cysts/metabolism , Liver Diseases/metabolism , Animals , Cysts/etiology , Humans , Immunohistochemistry , Liver Diseases/etiology , Mice , Polycystic Kidney, Autosomal Dominant/complications , Vascular Endothelial Growth Factor A/biosynthesis
9.
Gastroenterology ; 129(1): 220-33, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16012949

ABSTRACT

BACKGROUND & AIMS: Progressive liver disease is a severe complication of cystic fibrosis, a genetic disease characterized by impaired epithelial adenosine 3',5'-cyclic monophosphate-dependent secretion caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). In the liver, CFTR is expressed in cholangiocytes and regulates the fluid and electrolyte content of the bile. Glibenclamide, a sulfonylurea and a known CFTR inhibitor, paradoxically stimulates cholangiocyte secretion. We studied the molecular mechanisms underlying this effect and whether glibenclamide could restore cholangiocyte secretion in cystic fibrosis. METHODS: NRC-1 cells, freshly isolated rat cholangiocytes, isolated rat biliary ducts, and isolated biliary ducts from CFTR-defective mice (Cftr tm1Unc ) were used to study fluid secretion (by video-optical planimetry), glibenclamide-induced secretion (by high-performance liquid chromatography in cell culture medium), intracellular pH and intracellular Ca 2+ concentration transients [2'7'-bis(2-carboxyethyl)-5,6,carboxyfluorescein-acetoxymethylester and Fura-2 f-AM (5-Oxazolecarboxylic acid, 2-(6-(bis(2-((acetyloxy)methoxy)-2-oxoethyl)amino)-5-(2-(2-(bis(2-((acetyloxy)methoxy)-2-oxoethyl)amino)-5-methylphenoxy)ethoxy)-2-benzofuranyl)-, (acetyloxy)methyl ester) microfluorometry], gene expression (by reverse-transcription polymerase chain reaction), and changes in membrane capacitance (by patch-clamp experiments). RESULTS: Stimulation of cholangiocyte secretion by glibenclamide and tolbutamide required Cl - and was mediated by the sulfonylurea receptor 2B. Glibenclamide-induced secretion was blocked by inhibitors of exocytosis (colchicine, wortmannin, LY294002, and N -ethylmaleimide) and by inhibitors of secretory granule acidification (vanadate, bafilomycin A1, and niflumic acid) but was Ca 2+ and depolarization independent; membrane capacitance measurements were consistent with stimulation of vesicular transport and fusion. Glibenclamide, unlike secretin and forskolin, was able to stimulate secretion in Cftr tm1Unc mice, thus indicating that this secretory mechanism was preserved. CONCLUSIONS: The ability of glibenclamide to stimulate secretion in CFTR-defective mice makes sulfonylureas a model class of compounds to design drugs useful in the treatment of cystic fibrosis with liver impairment and possibly of other cholestatic diseases.


Subject(s)
Bile Ducts/drug effects , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Cystic Fibrosis/drug therapy , Glyburide/pharmacology , Hypoglycemic Agents/pharmacology , ATP-Binding Cassette Transporters/metabolism , Animals , Bile Ducts/cytology , Bile Ducts/metabolism , Body Fluids/metabolism , Calcium/metabolism , Cell Line , Cystic Fibrosis/metabolism , Cystic Fibrosis/physiopathology , Electric Capacitance , Electric Conductivity , Liver/drug effects , Liver/physiology , Mice , Mice, Inbred CFTR , Patch-Clamp Techniques , Potassium Channels/metabolism , Potassium Channels, Inwardly Rectifying/metabolism , Rats , Receptors, Drug/metabolism , Sulfonylurea Receptors
10.
Pancreas ; 26(4): 388-91, 2003 May.
Article in English | MEDLINE | ID: mdl-12717273

ABSTRACT

INTRODUCTION: Chronic pancreatitis (CP) is characterized by irreversible morphologic and functional alterations of the pancreas, clinically presenting with upper abdominal pain as well as exocrine and endocrine insufficiencies. According to a more recent hypothesis, the pathogenesis may involve genetic and immunologic factors. AIM: To investigate the major histocompatibility complex (MHC) genes as a genetic background of chronic pancreatitis. METHODOLOGY: Allelic polymorphisms were investigated in the genes of the MHC region (HLA B, DRB, DQB) with PCR-based methodologies (PCR-SSP) in 56 patients with CP (44 males and 12 females) and 183 normal controls (78 males and 105 females) of the same ethnic group. All patients and controls gave their informed consent. RESULTS: Among HLA-DRB1 genes, DRB1*04 was significantly higher in CP patients than in controls (26.78% versus 8.1%; pc < 0.003; OR = 4.1; CI = 1.85-9.06). DRB1*04 allele specificities in the DRB1*04-positive patients demonstrated significantly higher frequencies of DRB1*0401 allele (14.3% versus 1.1%; p = 0.00017; OR = 15.08; CI = 3.1-73.36). Neither HLA-B nor HLA-DQB1 associations with the disease were found. CONCLUSIONS: This study supports a role of HLA-DRB1*0401 as a susceptibility factor for patients with CP. HLA DRB1*0401 contains the 70QKRAA74 amino acid sequence, which is also expressed by several human pathogens, including Epstein-Barr virus. T cells may be triggered in the pancreatic tissue upon exposure to foreign peptides similar enough to cross-react and to break immunologic tolerance.


Subject(s)
HLA-DR Antigens/genetics , Pancreatitis/genetics , Adult , Aged , Chronic Disease , DNA/genetics , DNA/isolation & purification , Female , Gene Frequency , Genotype , HLA-DRB1 Chains , Humans , Male , Middle Aged , Pancreatitis/pathology
11.
Gastroenterology ; 124(3): 737-53, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12612912

ABSTRACT

BACKGROUND & AIMS: The biliary epithelium is involved both in bile production and in the inflammatory/reparative response to liver damage. Recent data indicate that inflammatory aggression to intrahepatic bile ducts results in chronic progressive cholestasis. METHODS: To understand the effects of nitric oxide on cholangiocyte secretion and biliary tract pathophysiology we have investigated: (1) the effects of proinflammatory cytokines on NO production and expression of the inducible nitric oxide synthase (NOS2), (2) the effects of NO on cAMP-dependent secretory mechanisms, and (3) the immunohistochemical expression of NOS2 in a number of human chronic liver diseases. RESULTS: Our results show that: (1) tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma, synergically stimulate NO production in cultured cholangiocytes through an increase in NOS2 gene and protein expression; (2) micromolar concentrations of NO inhibit forskolin-stimulated cAMP production by adenylyl cyclase (AC), cyclic adenosine monophosphate (cAMP)-dependent fluid secretion, and cAMP-dependent Cl(-) and HCO(3)(-) transport mediated by cystic fibrosis transmembrane conductance regulator (CFTR) and anion exchanger isoform 2, respectively; (3) cholestatic effects of NO and of proinflammatory cytokines are prevented by NOS-2 inhibitors and by agents (manganese(III)-tetrakis(4-benzoic acid)porphyrin [MnTBAP], urate, trolox) able to block the formation of reactive nitrogen oxide species (RNOS); (4) NOS2 expression is increased significantly in the biliary epithelium of patients with primary sclerosing cholangitis (PSC). CONCLUSIONS: Our findings show that proinflammatory cytokines stimulate the biliary epithelium to generate NO, via NOS2 induction, and that NO causes ductular cholestasis by a RNOS-mediated inhibition of AC and of cAMP-dependent HCO(3)(-) and Cl(-) secretory mechanisms. This pathogenetic sequence may contribute to ductal cholestasis in inflammatory cholangiopathies.


Subject(s)
Adenylyl Cyclase Inhibitors , Bile Ducts/metabolism , Cyclic AMP/physiology , Interferon-gamma/pharmacology , Nitric Oxide/biosynthesis , Tumor Necrosis Factor-alpha/pharmacology , Adenylyl Cyclases/metabolism , Animals , Bile Ducts/cytology , Bile Ducts, Intrahepatic/cytology , Bile Ducts, Intrahepatic/metabolism , Cell Line , Cyclic AMP/metabolism , Drug Synergism , Gene Expression/drug effects , Humans , Intracellular Fluid/metabolism , Ion Transport/drug effects , Liver Diseases/enzymology , Nitrates/metabolism , Nitric Oxide Donors/pharmacology , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type II , Nitrites/metabolism , Rats
12.
Acta Biomed ; 73(1-2): 37-40, 2002.
Article in English | MEDLINE | ID: mdl-12233276

ABSTRACT

This case is a report of a male, 52 year old, heavy smoker, with a history of about 10 years of alcohol abuse (he quitted in 1993), gastric resection for ulcer (Billroth II 1970), hypoparathyroidism and macroamylasemia, died for undiagnosed pancreatic carcinoma revealed at necroscopy. The only clinical evidence of carcinoma were pulmonary metastasis and paraneoplastic syndrome characterized from hyponatriemia due to inappropriate secretion of antidiuretic hormone and elevation of seric calcium caused by parathyroid hormone related protein. In patients without endocrine abnormalities, such unusual paraneoplastic syndrome could cause hypercalcemia, but in our patient, the increased calcemia did not reach abnormal levels due to the previous hypoparathyroidism. At present time, there are no clinical reports of parathyroid related protein secretion by pancreatic carcinoma and therefore, it could speculate that this modification together with ectopic secretion of antidiuretic hormone, represent a peculiar evidence of otherwise unknown and undetectable pancreatic carcinoma.


Subject(s)
Adenocarcinoma/metabolism , Hormones, Ectopic/metabolism , Hypercalcemia/etiology , Pancreatic Neoplasms/metabolism , Paraneoplastic Endocrine Syndromes/etiology , Proteins/metabolism , Adenocarcinoma/secondary , Alcoholism/complications , Fatal Outcome , Fatigue/etiology , Humans , Hypocalcemia/etiology , Hypoparathyroidism/etiology , Inappropriate ADH Syndrome/etiology , Lung Neoplasms/secondary , Male , Middle Aged , Parathyroid Hormone-Related Protein
SELECTION OF CITATIONS
SEARCH DETAIL
...