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1.
Aliment Pharmacol Ther ; 39(11): 1276-85, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24738701

ABSTRACT

BACKGROUND: Gut microbiota modifiers may have beneficial effects of non-alcoholic fatty liver disease (NAFLD) but randomised controlled trials (RCT) are lacking in children. AIM: To perform a double-blind RCT of VSL#3 vs. placebo in obese children with biopsy-proven NAFLD. METHODS: Of 48 randomised children, 44 (22 VSL#3 and 22 placebo) completed the study. The main outcome was the change in fatty liver severity at 4 months as detected by ultrasonography. Secondary outcomes were the changes in triglycerides, insulin resistance as detected by the homoeostasis model assessment (HOMA), alanine transaminase (ALT), body mass index (BMI), glucagon-like peptide 1 (GLP-1) and activated GLP-1 (aGLP-1). Ordinal and linear models with cluster confidence intervals were used to evaluate the efficacy of VSL#3 vs. placebo at 4 months. RESULTS: At baseline, moderate and severe NAFLD were present in 64% and 36% of PLA children and in 55% and 45% of VSL#3 children. The probability that children supplemented with VSL#3 had none, light, moderate or severe FL at the end of the study was 21%, 70%, 9% and 0% respectively with corresponding values of 0%, 7%, 76% and 17% for the placebo group (P < 0.001). No between-group differences were detected in triglycerides, HOMA and ALT while BMI decreased and GLP-1 and aGLP1 increased in the VSL#3 group (P < 0.001 for all comparisons). CONCLUSIONS: A 4-month supplement of VSL#3 significantly improves NAFLD in children. The VSL#3-dependent GLP-1 increase could be responsible for these beneficial effects. Trial identifier: NCT01650025 (www.clinicaltrial.gov).


Subject(s)
Dietary Supplements , Fatty Liver/therapy , Obesity/complications , Probiotics/therapeutic use , Alanine Transaminase/metabolism , Biopsy , Body Mass Index , Child , Double-Blind Method , Fatty Liver/diagnostic imaging , Fatty Liver/physiopathology , Female , Glucagon-Like Peptide 1/metabolism , Humans , Insulin Resistance , Male , Non-alcoholic Fatty Liver Disease , Severity of Illness Index , Treatment Outcome , Ultrasonography
2.
Endocr Relat Cancer ; 13(2): 629-40, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16728588

ABSTRACT

An increase in the risk of cancer is one of the consequences of obesity. The predominant cancers associated with obesity have a hormonal basis and include breast, prostate, endometrium, colon and gall-bladder cancers. Leptin, the key player in the regulation of energy balance and body weight control also acts as a growth factor on certain organs in both normal and disease states. Therefore, it is plausible that leptin acts to promote cancer growth by acting as a mitogenic agent. However, a direct role for leptin in endometrial cancer has not been demonstrated. In this study, we analyzed the proliferative role of leptin and the mechanism(s) underlying this action in endometrial cancers which express both short and long isoforms of leptin receptors. Treatment with leptin resulted in increased proliferation of ECC1 and Ishikawa cells. The promotion of endometrial cancer cell proliferation by leptin involves activation of STAT3 and ERK2 signaling pathways. Moreover, leptin-induced phosphorylation of ERK2 and AKT was dependent on JAK/STAT activation. Therefore blocking its action at the JAK/STAT level could be a rational therapeutic strategy for endometrial carcinoma in obese patients. We also found that leptin potently induces invasion of endometrial cancer cells in a Matrigel invasion assay. Leptin-stimulated invasion was effectively blocked by pharmacological inhibitors of JAK/STAT (AG490) and phosphatidylinositol 3-kinase (LY294002). Taken together these data indicate that leptin promotes endometrial cancer growth and invasiveness and implicate the JAK/STAT and AKT pathways as critical mediators of leptin action. Our findings have potential clinical implications for endometrial cancer progression in obese patients.


Subject(s)
Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , Leptin/pharmacology , Neoplasm Invasiveness , Protein Kinases/metabolism , Receptors, Cell Surface/agonists , Signal Transduction/drug effects , Cell Proliferation/drug effects , Enzyme Activation , Female , Humans , Janus Kinase 1 , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Obesity/metabolism , Phosphorylation , Protein Kinase Inhibitors/pharmacology , Protein Kinases/drug effects , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins c-akt/agonists , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Receptors, Leptin , STAT3 Transcription Factor/agonists , STAT3 Transcription Factor/metabolism
3.
Gut ; 53(1): 130-5, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14684587

ABSTRACT

BACKGROUND AND AIM: In this study, we compared the efficacy of triple therapy (interferon alfa, ribavirin, and amantadine) with standard therapy (interferon alfa and ribavirin) in treatment naïve patients with chronic hepatitis C virus (HCV). METHODS: In this prospective, randomised, double blind, placebo controlled, multicentre study, 85 patients (amantadine group) received a three drug regimen of interferon alfa-2b 3 million units three times per week, ribavirin 1000-1200 mg daily in divided doses, and amantadine 100 mg twice daily, and 86 patients (placebo group) received interferon alfa-2b, ribavirin, and identical placebo. Treatment was discontinued at 24 weeks if patients had detectable HCV RNA by polymerase chain reaction (PCR). All patients were followed for 24 weeks after completion of treatment. The primary end point was undetectable HCV-RNA by PCR at 24 weeks (sustained viral clearance) after completion of treatment. RESULTS: At the end of treatment, HCV RNA clearance was seen in 32.9% of the amantadine group and 38.4% of the placebo group (p=0.3). Sustained virological response was seen in 24.7% of the amantadine group and in 27.9% of the placebo group by intention to treat analysis; response rate was 30.4% and 34.8%, respectively, in those who completed 24 weeks of treatment. Poor response was seen in both groups among cirrhotics, African-Americans, genotype 1, and those with a higher viral load. By multivariate analysis, genotype 1, high viral load, and low serum albumin were the only predictors of poor response. Addition of amantadine to the standard regimen did not result in any unexpected side effects. CONCLUSION: Response to triple therapy of interferon alfa, ribavirin, and amantadine was similar to standard therapy of interferon alfa and ribavirin. Our results suggest that amantadine has no role in the management of HCV.


Subject(s)
Amantadine/therapeutic use , Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , Adult , Amantadine/adverse effects , Antiviral Agents/adverse effects , Double-Blind Method , Drug Therapy, Combination , Female , Hepacivirus/isolation & purification , Hepatitis C, Chronic/virology , Humans , Interferon alpha-2 , Interferon-alpha/adverse effects , Interferon-alpha/therapeutic use , Male , Middle Aged , Prospective Studies , RNA, Viral/analysis , Recombinant Proteins , Ribavirin/adverse effects , Ribavirin/therapeutic use , Risk Factors , Treatment Outcome
4.
Liver Transpl ; 7(11): 999-1001, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11699038

ABSTRACT

A patient was found to have numerous granulomata 7 years after orthotopic liver transplantation for primary sclerosing cholangitis (PSC) on a recent liver biopsy specimen. This histopathologic finding prompted a review of the literature to determine the commonality of this feature in the absence of the usual causes of granulomatous liver disease, none of which were found to be the cause of this patient's liver histopathologic state. The presence of posttransplantation granulomata is rare, and although previously reported to occur shortly after liver transplantation, this finding has not been reported previously with either PSC or vanishing bile duct syndrome. We are not aware of another case of granulomata associated with recurrent PSC or vanishing bile duct syndrome 7 years after liver transplantation.


Subject(s)
Bile Duct Diseases/complications , Bile Duct Diseases/etiology , Granuloma/etiology , Liver Diseases/etiology , Liver Transplantation/adverse effects , Bile Duct Diseases/pathology , Female , Graft Rejection/etiology , Humans , Liver/pathology , Middle Aged , Postoperative Period , Time Factors
5.
Free Radic Biol Med ; 30(8): 846-57, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11295527

ABSTRACT

Hepatic stellate cells (HSCs) are responsible for type I collagen deposition in liver fibrosis that leads to cirrhosis. The purpose of this study was to examine potential molecular signals that lead to increased alpha(2)(I) collagen gene expression by acetaldehyde, the primary metabolite of alcohol and malondialdehyde (MDA), a lipid peroxidation product known to be associated with chronic liver injury. MDA and the combination of MDA and acetaldehyde were employed to determine the effect on alpha(2)(I) collagen gene expression as assessed by transient transfection analysis and reverse transcriptase polymerase chain reaction (RT-PCR). Immunoblot and subsequent immunoprecipitation analysis examined stress-activated protein kinase (SAPK) activity. Cotransfection with a dominant negative mutant for c-jun nuclear kinase (dnJNK1) was also employed with the alpha(2)(I) collagen promoter. MDA increased alpha(2)(I) collagen gene expression nearly 2.5- to 3-fold, however there was no synergistic effect of the combination of acetaldehyde and MDA on alpha(2)(I) collagen gene activation and expression. Acetaldehyde, MDA, or both significantly increased JNK activity when compared to untreated stellate cells. The dnJNK1 expression vector abrogated alpha(2)(I) collagen transgene activity. In conclusion, JNK activation appears to be critical in the signaling cascade of oxidative metabolites of chronic alcohol-related liver injury and collagen gene activation.


Subject(s)
Acetaldehyde/pharmacology , Collagen/genetics , Liver/drug effects , Malondialdehyde/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Transcriptional Activation/drug effects , Animals , Cells, Cultured , Collagen Type I , JNK Mitogen-Activated Protein Kinases , Liver/cytology , Liver/enzymology , Liver/metabolism , MAP Kinase Signaling System/drug effects , Male , Mitogen-Activated Protein Kinases/genetics , Mutation/genetics , Phosphorylation , Precipitin Tests , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Transfection , Transgenes/genetics
6.
J Biol Chem ; 275(46): 35715-22, 2000 Nov 17.
Article in English | MEDLINE | ID: mdl-10969082

ABSTRACT

The present study examined the roles of peroxisome proliferator-activated receptors (PPAR) in activation of hepatic stellate cells (HSC), a pivotal event in liver fibrogenesis. RNase protection assay detected mRNA for PPARgamma1 but not that for the adipocyte-specific gamma2 isoform in HSC isolated from sham-operated rats, whereas the transcripts for neither isoforms were detectable in HSC from cholestatic liver fibrosis induced by bile duct ligation (BDL). Semi-quantitative reverse transcriptase-polymerase chain reaction confirmed a 70% reduction in PPARgamma mRNA level in HSC from BDL. Nuclear extracts from BDL cells showed an expected diminution of binding to PPAR-responsive element, whereas NF-kappaB and AP-1 binding were increased. Treatment of cultured-activated HSC with ligands for PPARgamma (10 microm 15-deoxy-Delta(12,14)-PGJ(2) (15dPGJ(2)); 0.1 approximately 10 microm BRL49653) inhibited DNA and collagen synthesis without affecting the cell viability. Suppression of HSC collagen by 15dPGJ(2) was abrogated 70% by the concomitant treatment with a PPARgamma antagonist (GW9662). HSC DNA and collagen synthesis were inhibited by WY14643 at the concentrations known to activate both PPARalpha and gamma (>100 microm) but not at those that only activate PPARalpha (<10 microm) or by a synthetic PPARalpha-selective agonist (GW9578). 15dPGJ(2) reduced alpha1(I) procollagen, smooth muscle alpha-actin, and monocyte chemotactic protein-1 mRNA levels while inducing matrix metalloproteinase-3 and CD36. 15dPGJ(2) and BRL49653 inhibited alpha1(I) procollagen promoter activity. Tumor necrosis factor alpha (10 ng/ml) reduced PPARgamma mRNA, and this effect was prevented by the treatment with 15dPGJ(2). These results demonstrate that HSC activation is associated with the reductions in PPARgamma expression and PPAR-responsive element binding in vivo and is reversed by the treatment with PPARgamma ligands in vitro. These findings implicate diminished PPARgamma signaling in molecular mechanisms underlying activation of HSC in liver fibrogenesis and the potential therapeutic value of PPARgamma ligands for liver fibrosis.


Subject(s)
Liver/cytology , Liver/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Thiazolidinediones , Transcription Factors/metabolism , Animals , Cell Size/drug effects , Cell Survival/drug effects , Cells, Cultured , Collagen/biosynthesis , Collagen/genetics , DNA/biosynthesis , Gene Expression Regulation/drug effects , Liver/drug effects , Liver/pathology , Liver Cirrhosis, Biliary/genetics , Liver Cirrhosis, Biliary/metabolism , Liver Cirrhosis, Biliary/pathology , Liver Cirrhosis, Experimental/genetics , Liver Cirrhosis, Experimental/metabolism , Liver Cirrhosis, Experimental/pathology , Male , Promoter Regions, Genetic/genetics , Prostaglandin D2/analogs & derivatives , Prostaglandin D2/pharmacology , Protein Binding , Protein Isoforms/agonists , Protein Isoforms/genetics , Protein Isoforms/metabolism , Pyrimidines/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Receptors, Cytoplasmic and Nuclear/agonists , Receptors, Cytoplasmic and Nuclear/genetics , Rosiglitazone , Thiazoles/pharmacology , Transcription Factors/agonists , Transcription Factors/genetics , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/pharmacology
7.
JAMA ; 284(4): 450-6, 2000 Jul 26.
Article in English | MEDLINE | ID: mdl-10904508

ABSTRACT

CONTEXT: Hepatitis C virus (HCV) infection may resolve (viral clearance), persist without complications, or cause end-stage liver disease (ESLD). The frequency and determinants of these outcomes are poorly understood. OBJECTIVE: To assess the incidence and determinants of viral clearance and ESLD among persons who acquired HCV infection from injection drug use. DESIGN AND SETTING: Community-based prospective cohort study with enrollment in 1988-1989 and a median follow-up of 8.8 years. SUBJECTS: A total of 1667 persons aged 17 years or older with a history of injection drug use and an HCV antibody-positive test result during follow-up. MAIN OUTCOME MEASURES: Viral clearance was assessed in a subset of 919 patients and defined as failure to detect HCV RNA in at least 2 consecutive samples collected 5 or more months apart. End-stage liver disease was assessed at semiannual visits and by review of medical records and death certificates and defined by the presence of ascites, esophageal varices, or hepatic encephalopathy, or when ESLD was stated as a cause of death. RESULTS: Viral clearance was observed in 90 persons who were compared with 722 with persistent viremia, while the viremia of 107 was not resolved. Viral clearance occurred more often in nonblacks (adjusted odds ratio [OR], 5.15; 95% confidence interval [CI], 2.60-10.17) and those not infected with human immunodeficiency virus (HIV) (adjusted OR, 2.19; 95% CI, 1.26-3.47). Forty cases of ESLD were observed throughout follow-up (incidence, 3.1 per 1000 person-years). In a multivariate model, risk of ESLD was higher for persons aged 38 years or older at enrollment (adjusted relative incidence, 3.67; 95% CI, 1.96-6.88) and who reported ingestion of more than 260 g of alcohol per week (adjusted relative incidence, 3.60; 95% CI, 1.73-7.52). Of 210 patients without ESLD randomly selected for biopsy, only 2 had cirrhosis. CONCLUSIONS: Our results indicate that although HCV infection can be self-limited or associated with ESLD, the majority of adults have persistent viremia without clinically demonstrable liver disease. Further research is needed to explain the less frequent clearance of HCV infection among black persons and to improve utilization of treatment for those infected in the context of injection drug use. JAMA. 2000;284:450-456


Subject(s)
Hepatitis C/complications , Liver Diseases/etiology , Viremia , Adult , Cohort Studies , Disease Progression , Female , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis C/pathology , Hepatitis C/virology , Humans , Incidence , Liver/pathology , Liver Diseases/epidemiology , Logistic Models , Male , RNA, Viral/blood , Risk Factors , Substance Abuse, Intravenous/complications , Surveys and Questionnaires
8.
Semin Gastrointest Dis ; 11(2): 84-95, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10803633

ABSTRACT

Since the National Institutes of Health (NIH) Consensus Conference in 1997, our understanding of the natural history of hepatitis C (HCV) infection and our ability to treat patients has improved. Thus, a large number of clinical studies, confounding terminology, and a growing dilemma in targeting particular populations for treatment who have HCV infection, will continue to be at the forefront of clinical research and treatment. In this report, we examine which HCV-infected populations of patients should be treated. Beginning with treatment guidelines from the NIH Consensus Conference, and a brief overview of the terminology used in the HCV literature, we subsequently review data regarding treatment outcomes based on HCV viral load, genotype, and various epidemiological factors. Similarly, more challenging treatment strategies are discussed for patients with HCV infection, including those with ongoing psychiatric disorders, patients who are coinfected with the human immunodeficiency virus and HCV, and those patients with normal serum transaminases. Finally, a review and guidelines about other HCV treatment dilemmas, including patients with chronic renal failure on hemodialysis, patients who have undergone renal transplantation, and treatment of patients acutely exposed to HCV are also addressed.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C/diagnosis , Hepatitis C/drug therapy , Patient Selection , Practice Guidelines as Topic/standards , Age Factors , Female , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/drug therapy , Humans , Male , Middle Aged , Risk Factors , Severity of Illness Index , Sex Factors
9.
Liver ; 19(2): 135-44, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10220744

ABSTRACT

AIMS/BACKGROUND: Liver stellate cells are transdifferentiated to collagen-producing myofibroblast-like cells in vivo during liver injury or when placed in culture. The purpose of this study was to determine the presence of retinoids and the expression of the immediate early genes as they relate to the transdifferentiation of liver stellate cells in culture. METHODS: Rat liver stellate cells were studied immediately after isolation or sequentially after culture for varying periods of time. RNA was isolated and specific messages were determined by RT-PCR. Cells were also isolated for determination of retinoid autofluorescence and immunofluorescent staining with specific antibodies by laser confocal microscopy. RESULTS: c-fos message and immunoprotein were high in the freshly isolated cells prior to culture, while c-myc expression increased markedly after one day of culture. Both c-fos and c-myc gene expression decreased prior to the transdifferentiation of the cells to myofibroblast-like cells and to the increase in alpha 1(I) and alpha 2(I) collagen messages and collagen production. The presence of retinoid autofluorescence and retinoic acid receptor (RAR-alpha and RAR-beta) messages and RAR-beta immunoprotein persisted during initial transdifferentiation of the stellate cells. CONCLUSIONS: This study shows a high initial level of c-fos expression and a transient increase in c-myc expression followed by a decrease to lower levels prior to transdifferentiation and collagen production by stellate cells. A total loss of retinoid autofluorescence or a decrease in RAR-alpha or RAR-beta are not required for initial transdifferentiation of stellate cells or collagen production.


Subject(s)
Liver/cytology , Proto-Oncogene Proteins c-myc/metabolism , Animals , Cell Differentiation , Cells, Cultured , Collagen/metabolism , Fibroblasts/cytology , Immunohistochemistry , In Vitro Techniques , Liver/metabolism , Male , Microscopy, Confocal , Rats , Rats, Sprague-Dawley , Receptors, Retinoic Acid/metabolism , Reverse Transcriptase Polymerase Chain Reaction
10.
Alcohol Clin Exp Res ; 23(2): 279-84, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10069557

ABSTRACT

Protein kinase C (PKC) inhibitors decrease alpha1(I) collagen mRNA in stellate cells exposed to 200 micromol/liter of acetaldehyde. The purpose of these studies was to determine whether PKC activation plays a role in transcriptional activation of the alpha2(I) collagen gene. Cultured stellate cells were exposed to 200 micromol/liter of acetaldehyde. PKC, inositol triphosphate, diacylglycerol (DAG), and intracellular free calcium (Ca2+i) were measured. Alpha1(I) and alpha2(I) collagen messages were determined by reverse transcriptase-polymerase chain reaction. Activation of the alpha2(I) collagen promoter was determined in transiently transfected stellate cells. Acetaldehyde exposure enhanced PKC activity translocation to the particulate fraction at 20 min. Acetaldehyde did not increase Ca2+i, or inositol triphosphate but increased DAG levels at 20 min and 3 hr. Acetaldehyde increased both the alpha1(I) and alpha2(I) collagen messages in stellate cells. Calphostin C, a specific PKC inhibitor, which blocks DAG binding, eliminated both activation of the alpha2(I) collagen promoter by acetaldehyde and mRNA production by reverse transcriptase-polymerase chain reaction analysis. Similarly, D609, an inhibitor of DAG production, also inhibited alpha2(I) collagen gene expression. This study shows that collagen production by acetaldehyde is mediated by a calcium-independent PKC mechanism.


Subject(s)
Acetaldehyde/pharmacology , Calcium/metabolism , Collagen/metabolism , Liver/metabolism , Protein Kinase C/metabolism , Animals , Cells, Cultured , Collagen/genetics , Collagen Type I , Diglycerides/metabolism , Enzyme Activation/physiology , Fura-2/metabolism , Gene Expression Regulation , Inositol 1,4,5-Trisphosphate/metabolism , Liver/cytology , Liver/enzymology , Male , RNA/isolation & purification , RNA/metabolism , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects
11.
Arch Biochem Biophys ; 361(1): 7-16, 1999 Jan 01.
Article in English | MEDLINE | ID: mdl-9882423

ABSTRACT

We recently identified three areas of Sp1 binding located between -568 and -453 of the 5' flanking region of the murine alpha2(I) collagen promoter which are necessary for optimal activity. We now identify two additional regions of Sp1 binding located at -371 to -351 (region 4) and at -690 to -613 (region 5), which when mutated increased promoter activity in transfected rat hepatic stellate cells indicating they contain negative regulatory elements. AP-2 bound to region 4 while YY1 bound most strongly to region 5. AP-2 decreased Sp1 binding to region 4 and had a dual effect on Sp1 binding to region 5 decreasing and increasing Sp1 binding at low and high concentrations of AP-2, respectively. YY1 enhanced Sp1 binding to both regions. AP-2 inhibited or enhanced the stimulatory effect of a transfected Sp1 expression vector on the alpha2(I) collagen promoter in Drosophila cells at low or high AP-2 expression, respectively. YY1 enhanced or inhibited the activation of the promoter by low or high Sp1 expression, respectively. This study identifies two negative regulatory elements in the murine alpha2(I) collagen promoter and shows that AP-2 and YY1 interact with Sp1 at these sites and can inhibit the activating action of Sp1.


Subject(s)
Collagen/genetics , Promoter Regions, Genetic/genetics , Repressor Proteins/genetics , Acetaldehyde/pharmacology , Animals , Collagen/biosynthesis , DNA-Binding Proteins/metabolism , Electrophoresis, Polyacrylamide Gel , Erythroid-Specific DNA-Binding Factors , Gene Expression Regulation/drug effects , Male , Mice , Nuclear Proteins/metabolism , Oligonucleotides/metabolism , Promoter Regions, Genetic/drug effects , Protein Binding/drug effects , Protein Binding/genetics , Rats , Rats, Sprague-Dawley , Sp1 Transcription Factor/metabolism , Transcription Factor AP-2 , Transcription Factors/metabolism , YY1 Transcription Factor
12.
Biochem Biophys Res Commun ; 244(1): 178-82, 1998 Mar 06.
Article in English | MEDLINE | ID: mdl-9514867

ABSTRACT

Leptin is a peptide hormone that appears critical in regulating Fat metabolism. Recently, circulating leptin levels were reported higher in patients with alcoholic cirrhosis. In health, hepatic stellate cells store retinoids, but following liver injury they transdifferentiate into myofibroblast-like cells with loss of the retinoid stores. Leptin expression was demonstrated by detection of leptin mRNA by RT-PCR analysis and by immunohistochemistry viewed with confocal microscopy in transdifferentiated stellate cells after 14 days, or more, of culture. Leptin expression was not found in freshly isolated quiescent stellate cells. Leptin expression was not demonstrated in freshly isolated or cultured Kupffer cells. Treatment of activated stellate cells with either 1 microM retionic acid or 10 microM retinol acetate resulted in the inhibition of leptin mRNA expression. The observation that activated stellate cells in culture can express leptin has implications for understanding adipocyte biology in liver disease and treatment of malnutrition in cirrhotics.


Subject(s)
Liver/cytology , Liver/metabolism , Protein Biosynthesis , Animals , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Separation , Cells, Cultured , Diterpenes , Leptin , Liver/drug effects , Male , Obesity/metabolism , Obesity/pathology , Proteins/antagonists & inhibitors , Proteins/genetics , Proteins/isolation & purification , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley , Retinyl Esters , Tretinoin/pharmacology , Vitamin A/analogs & derivatives , Vitamin A/pharmacology
13.
Arch Biochem Biophys ; 341(1): 140-52, 1997 May 01.
Article in English | MEDLINE | ID: mdl-9143363

ABSTRACT

Acetaldehyde activates the mouse alpha 2(I) collagen promoter and this effect is mediated in part by increased binding of nuclear factor I (NF-I). Additional mechanisms may exist since deletions in the promoter upstream to the NF-I binding site prevented enhancement by acetaldehyde. Three adjacent areas of binding by nuclear proteins from activated hepatic stellate cells were identified at -568 to -554 (region 1), -542 to -518 (region 2), and -473 to -453 (region 3) of the promoter using DNase I protection analyses. Multiple DNA-protein complexes were formed in electrophoretic mobility shift assays with oligonucleotide probes specifying the three regions. Sp1 and NF-1 bound to all three regions, while Sp3 bound to region 2. Acetaldehyde decreased nuclear protein binding to all three regions. Mutations of regions 1, 2, and 3 reduced basal activity of the promoter and inhibited acetaldehyde stimulation in transfected stellate cells. Acetaldehyde inhibited the stimulatory effect of the Sp1 vector pPacSp1 on the promoter in transfected Drosophila cells. In conclusion, three regions of Sp1 binding were identified and are required for optimal activity of the alpha 2(I) collagen promoter. Sp1 is required for basal activity of the alpha 2(I) collagen promoter; however, the enhancing effect of acetaldehyde on the promoter is not mediated by Sp1.


Subject(s)
Acetaldehyde/pharmacology , CCAAT-Enhancer-Binding Proteins , Collagen/genetics , Promoter Regions, Genetic , Sp1 Transcription Factor/metabolism , Animals , Antibodies/immunology , Antibodies/metabolism , Blotting, Western , Cells, Cultured , Cross-Linking Reagents/metabolism , DNA Footprinting , DNA-Binding Proteins/metabolism , Liver , Male , Mice , Mutation , NFI Transcription Factors , Nuclear Proteins/immunology , Nuclear Proteins/metabolism , Rats , Rats, Sprague-Dawley , Sp3 Transcription Factor , Transcription Factors/metabolism , Transfection/genetics , Y-Box-Binding Protein 1
14.
G Chir ; 18(4): 222-8, 1997 Apr.
Article in Italian | MEDLINE | ID: mdl-9303637

ABSTRACT

Nonparasitic cysts of the spleen are uncommon and often result from blunt abdominal trauma. Nonsurgical management of blunt splenic injuries increases the number of observations of the post-traumatic cysts. Complications (infection, rupture and hemorrhage) are lifethreatening, difficult to diagnose and require urgent surgical management. Until recently, splenectomy has been the primary choice of treatment of these cysts. Small (< 4 cm) asymptomatic post-traumatic pseudocysts stand a reasonable chance of involution with time (3-36 months) and so may be initially observed. Splenic preservation by partial splenectomy, enucleation or by marsupialization is actually recommended in children when technically feasible. Splenectomy is required for voluminous, central, multifocal cysts, in the presence of complications and in the adults with low immunologic risk. The Authors report 5 cases of large cysts successfully treated by splenectomy with one 12-year-old girl treated in emergency for infection by Salmonella.


Subject(s)
Cysts/surgery , Splenectomy , Splenic Diseases/surgery , Adult , Child , Cysts/pathology , Female , Humans , Length of Stay , Spleen/pathology , Splenic Diseases/pathology
15.
Arch Biochem Biophys ; 331(2): 187-93, 1996 Jul 15.
Article in English | MEDLINE | ID: mdl-8660697

ABSTRACT

The effect of acetaldehyde in activating the mouse alpha2(I) collagen promoter in transiently transfected rat activated stellate cells and the possible mediating effect of transforming growth factor beta1 (TGFbeta1) on type I collagen gene expression were determined. Acetaldehyde and TGFbeta1, each had a similar effect in activating the wild-type promoter, but failed to activate the promoter with a -352 to -104 deletion, or the promoter containing a 3-bp substitution between -305 and -303 in the putative nuclear factor I (NF-I) binding site. The effects of acetaldehyde and TGFbeta1 are therefore mediated by a similar factor or factors that bind to the NF-I consensus sequence within the region -352 to -104. Additional factors may also play a role in the effects of acetaldehyde and TGFbeta1, which have similar effects on the wild-type promoter, but become additive in activating the promoter with a more distal deletion containing a cis-repressor element. Pretreatment of activated stellate cells with antibodies to TGFbeta1 suppressed the effect of acetaldehyde in increasing the alpha1(I) collagen message, indicating that TGFbeta1 mediates the effect of the acetaldehyde-induced increase in the expression of the alpha1(I) collagen gene which also contains NF-I binding sites.


Subject(s)
Acetaldehyde/pharmacology , Adipocytes/physiology , Collagen/genetics , Liver/drug effects , Animals , Base Sequence , Cells, Cultured , Drosophila melanogaster , Gene Expression Regulation/drug effects , Liver/cytology , Male , Mice , Molecular Sequence Data , Oligodeoxyribonucleotides/chemistry , Promoter Regions, Genetic , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Transfection , Transforming Growth Factor beta/pharmacology
16.
Hepatology ; 21(6): 1640-8, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7768510

ABSTRACT

Acetaldehyde has been shown to increase collagen production in cultured rat myofibroblastlike cells and to activate the mouse alpha 2(I) collagen promoter in transfected NIH 3T3 cells. Nuclear factor I (NF-I), a CCAAT binding transcription factor, is known to bind and activate the alpha 1(I) and alpha 2(I) collagen genes. Activation of the alpha 2(I) collagen promoter was not observed when the NF-I binding site of the promoter was deleted. In this study, we determined if acetaldehyde influences the binding of NF-I to the alpha 2(I) collagen promoter. Nuclear proteins extracted from NIH 3T3 cells, or myofibroblastlike cells, 36 hours after the addition of acetaldehyde (200 mumol/L) in serum-free media showed increased binding to the consensus sequence of the NF-I binding site by DNase I protection analysis and by electrophoretic mobility shift assay (EMSA) as compared with control nuclear extracts that were not exposed to acetaldehyde. Furthermore, nuclear proteins extracted from myofibroblastlike cells that had been previously exposed to acetaldehyde had a marked increase in NF-I protein, as shown by Western blot with NF-I antibodies. Antisera to NF-I resulted in a slow migrating DNA-protein-antibody complex (supershift) on EMSA. However, the NF-I antibody did not supershift all the DNA-protein complexes, and the supershift band was not increased with nuclear proteins from acetaldehyde-treated cells despite the increased binding of these nuclear protein preparations to the NF-I oligo. Therefore, nuclear proteins, in addition to NF-I, bind to the NF-I consensus sequence and may have their binding altered by acetaldehyde.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Acetaldehyde/pharmacology , CCAAT-Enhancer-Binding Proteins , Collagen/genetics , DNA-Binding Proteins/metabolism , DNA/metabolism , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Transcription Factors , 3T3 Cells , Animals , Base Sequence , Binding Sites , Collagen/biosynthesis , Consensus Sequence , DNA/chemistry , Deoxyribonuclease I , Fibroblasts/metabolism , Mice , Molecular Sequence Data , Muscles , NFI Transcription Factors , Nuclear Proteins/isolation & purification , Rats , Recombinant Proteins/biosynthesis , Transfection , Y-Box-Binding Protein 1
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