The Impact of Radiofrequency Ablation on Survival Outcomes and Stent Patency in Patients with Unresectable Cholangiocarcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Endoluminal biliary radiofrequency ablation (RFA) has been proposed as a palliative treatment for patients with malignant biliary obstruction (MBO) in order to improve stent patency and survival. However, the existing data on patients with inoperable extrahepatic cholangiocarcinoma (eCCA) are conflicting. We performed a meta-analysis of randomized trials comparing RFA plus stenting versus stenting alone in patients with inoperable eCCA. We searched for trials published in the PubMed/MEDLINE, Scopus, and Cochrane databases up to November 2023. Data extraction was conducted from published studies, and a quality assessment was carried out in accordance with the guidelines recommended by the Cochrane Collaboration. Hazard ratios (HRs) with 95% CI were estimated from the trials. The primary endpoints of interest were overall survival and stent patency. Out of 275 results, 5 randomized trials and 370 patients were included. While overall survival was not different between the groups (HR 0.62; 95% CI 0.36-1.07; p = 0.09; I2 = 80%;), the subgroup analysis of studies employing plastic stents showed a trend toward better survival in the RFA-treated group (HR 0.42; 95% CI 0.22-0.80; p = 0.009; I2 = 72%). Stent patency was improved in patients receiving RFA (HR 0.64; 95% CI 0.45-0.90; p = 0.01; I2 = 23%). Adverse events were not different between the groups (OR 1.21; 95% CI 0.69-2.12; p = 0.50; I2 = 0%). Despite the promising results, high heterogeneity and potential biases in the included studies suggest the need for further high-quality randomized trials to explore the potential cumulative effects of RFA on CCA treatment outcomes.

Ustekinumab safety and effectiveness in patients with ulcerative colitis: results from a large real-life study.

BACKGROUND: Ustekinumab (UST) is an interleukin-12/interleukin-23 receptor antagonist recently approved for treating ulcerative colitis (UC) but with limited real-world data. Therefore, we evaluated the effectiveness and safety of UST in patients with UC in a real-world setting. RESEARCH DESIGN AND METHODS: This is a multicenter, retrospective, observational cohort study. The primary endpoints were the clinical remission rate (partial Mayo score, PMS, ≤1) and the safety of UST. Other endpoints were corticosteroid-free remission (CSFR) rate, clinical response rate (PMS reduction of at least 2 points), and fecal calprotectin (FC) reduction at week 24. RESULTS: We included 256 consecutive patients with UC (M/F 139/117, median age 52). The clinical remission and clinical response rates at eight weeks were 18.7% (44/235) and 53.2% (125/235), respectively, and 27.6% (42/152) and 61.8% (94/152) at 24 weeks, respectively. At 24 weeks, CSFR was 20.3% (31/152), and FC significantly dropped at week 12 (p = 0.0004) and 24 (p = 0.038). At eight weeks, patients naïve or with one previous biologic treatment showed higher remission (p = 0.002) and clinical >response rates (p = 0.018) than patients previously treated with ≥ 2. Adverse events occurred in six patients (2.3%), whereas four patients (1.6%) underwent colectomy. CONCLUSION: This real-world study shows that UST effectively and safely treats patients with UC.

Gastrointestinal motility disorder assessment in systemic sclerosis.

OBJECTIVES: SSc is a clinically heterogeneous and generalized disease, characterized by thickness of the connective tissue of the skin and internal organs, such as the digestive tract, impairing gastrointestinal (GI) motility. Our aim is to evaluate retrospectively abnormalities of oesophageal motility, gastric emptying, oro-cecal transit time (OCTT) and small intestine bacterial overgrowth (SIBO) in a large cohort of SSc patients. METHODS: Ninety-nine SSc patients were included in the study. Forty-two patients underwent oesophageal conventional manometry, 45 performed a [(13)C]octanoic acid breath test to measure gastric emptying time and all 99 patients performed a lactulose breath test in order to evaluate OCTT and SIBO. Data were compared with healthy controls. RESULTS: In SSc patients, median lower oesophageal sphincter (LOS) pressure [14 mmHg (25th-75th; 8-19) vs 24 mmHg (19-28); P < 0.01] and median wave amplitude [30 mmHg (16-70) vs 72 mmHg (48-96); P < 0.01] were lower than in controls. Oesophageal involvement, defined as reduced LOS pressure and ineffective oesophageal motility pattern, was encountered in 70% of SSc patients. A delayed gastric emptying time was present in 38% of SSc patients: mean t½ was 141 ± 79 min vs 90 ± 40 min of controls (P < 0.01). Also, OCTT was significantly delayed in SSc: median OCTT was 160 min (25th-75th; 135-180) vs 105 min (25th-75th; 90-135) of controls (P < 0.01). SIBO was observed in 46% of SSc compared with 5% of controls (P < 0.01). CONCLUSION: GI involvement is very frequent in SSc patients. Oesophagus and small bowel are more frequently impaired, whereas delayed gastric emptying is less common.

Role of small intestinal bacterial overgrowth and Helicobacter pylori infection in chronic spontaneous urticaria: a prospective analysis.

The aim of this study is to assess the associations between chronic spontaneous urticaria (CSU), Helicobacter pylori infection and small intestinal bacterial overgrowth. Forty- eight patients with CSU were studied by scoring the urticaria activity and assesing the quality of life. Patients with H. pylori infection (n=11) or small intestinal bacterial overgrowth (n=13) were specifically treated for one week and clinically evaluated both before and 4 weeks after the eradication therapy. Eradication of H. pylori infection led to a significant improvement in CSU (p<0.002). In contrast, eradication of small intestinal bacterial overgrowth was not associated with any clinical improvement in CSU, despite the fact that these patients had statistically significant more urticaria activity at baseline. Thus there is no evidence to support the eradication of small intestinal bacterial overgrowth in CSU, but eradication of H. pylori infection may result in an improvement of the disease.

Serological response after anti-SARS-CoV-2 BNT162b2 vaccine in IBD patients on biological therapy: a monocentric case-control study.

BACKGROUND: Inflammatory bowel disease (IBD) patients on biological therapy are receiving vaccines against severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). However, it is unclear if IBD therapy could influence the response to this vaccine. In a case-control study, we assessed the antibody profiling after anti-SARS-CoV-2 BNT162b2 vaccine in IBD patients on biological therapy. METHODS: We analyzed seroprevalence and antibody titer, after 14 weeks from the first BNT162b2 vaccine dose, in IBD patients on biological therapy and health care workers (HCWs). In IBD patients, medical history and disease data were recorded. RESULTS: Eighty-two subjects were enrolled in this study. Among them, 40 were IBD patients on biological therapy and 42 were HCWs. All subjects developed an IgG anti-Spike antibody titer above the cut-off. IBD patients on biological therapy developed a lower antibody titer than HCWs (P<0.00001). No differences were reported in patients who received at least one dose of the vaccine within a period of 7 days from the last biological drug administration, compared to all other IBD patients. A difference was found between patients who were on concomitant immunosuppressive therapy and patients on sole biological therapy (P=0.0287). Patients with presence of any sign of disease activity (clinical, endoscopic or laboratory) showed a higher development of antibody titer compared to those in complete disease remission (P=0.0468). CONCLUSIONS: Our data indicate that in IBD patients, treatment with biological therapies do not affect the seroprevalence but leads to a lower antibody titer development after anti-SARS-CoV-2 BNT162b2 vaccine.

Use of tofacitinib as first or second-line therapy is associated with better outcomes in patients with ulcerative colitis: data from a real-world study.

BACKGROUND: Data regarding the real-world (RW) use of tofacitinib (TOF) in patients with ulcerative colitis (UC) are limited. We aimed to investigate TOF's RW efficacy and safety in Italian UC patients. RESEARCH DESIGN AND METHODS: A retrospective assessment of clinical and endoscopic activity was performed according to the Mayo score. The primary endpoints were to evaluate the effectiveness and safety of TOF. RESULTS: We enrolled 166 patients with a median follow-up of 24 (IQR 8-36) weeks. Clinical remission was achieved in 61/166 (36.7%) and 75/166 (45.2%) patients at 8-week and 24-week follow-ups, respectively. The optimization was requested in 27 (16.3%) patients. Clinical remission was achieved more frequently when TOF was used as a first/second line rather than a third/fourth line treatment (p = 0.007). Mucosal healing was reported in 46% of patients at the median follow-up time. Colectomy occurred in 8 (4.8%) patients. Adverse events occurred in 12 (5.4%) patients and severe in 3 (1.8%). One case of simple Herpes Zoster and one of renal vein thrombosis were recorded. CONCLUSIONS: Our RW data confirm that TOF is effective and safe in UC patients. It performs remarkably better when used as the first/second line of treatment.

Upper Gastrointestinal Endoscopy Quality in Italy: A Nationwide Study.

BACKGROUND AND AIMS: International guidelines advise improving esophagogastroduodenoscopy (EGD) quality in Western countries, where gastric cancer is still diagnosed in advanced stages. This nationwide study investigated some indicators for the quality of EGD performed in endoscopic centers in Italy. METHODS: Clinical, endoscopic, and procedural data of consecutive EGDs performed in one month in the participating centers were reviewed and collected in a specific database. Some quality indicators before and during endoscopic procedures were evaluated. RESULTS: A total of 3,219 EGDs performed by 172 endoscopists in 28 centers were reviewed. Data found that some relevant information (family history for GI cancer, smoking habit, use of proton pump inhibitors) were not collected before endoscopy in 58.5-80.7% of patients. Pre-endoscopic preparation for gastric cleaning was routinely performed in only 2 (7.1%) centers. Regarding the procedure, sedation was not performed in 17.6% of patients, and virtual chromoendoscopy was frequently (>75%) used in only one (3.6%) center. An adequate sampling of the gastric mucosa (i.e., antral and gastric body specimens) was heterogeneously performed, and it was routinely performed only by 23% of endoscopists, and in 14.3% centers. CONCLUSIONS: Our analysis showed that the quality of EGD performed in clinical practice in Italy deserves to be urgently improved in different aspects.

Digital single-operator cholangioscopy in diagnostic and therapeutic bilio-pancreatic diseases: A prospective, multicenter study.

BACKGROUND AND AIM: Digital single-operator cholangioscopy (D-SOC) is an endoscopic procedure that is increasingly used for the management of bilio-pancreatic diseases. We aimed to investigate the efficacy and safety of D-SOC for diagnostic and therapeutic indications. METHODS: This is a multicenter, prospective study(January 2016-June 2019) across eighteen tertiary centers. The primary outcome was procedural success of D-SOC. Secondary outcomes were: D-SOC visual assessment and diagnostic yield of SpyBite biopsy in cases of biliary strictures, stone clearance rate in cases of difficult biliary stones, rate of adverse events(AEs) for all indications. RESULTS: D-SOC was performed in 369 patients (201(54,5%) diagnostic and 168(45,5%)therapeutic). Overall, procedural success rate was achieved in 360(97,6%) patients. The sensitivity, specificity, PPV, NPV and accuracy in biliary strictures were: 88,5%, 77,3%, 83,3%, 84,1% and 83,6% for D-SOC visual impression; 80,2%, 92,6%, 95,1%, 72,5% and 84,7% for the SpyBite biopsy, respectively. For difficult biliary stones, complete duct clearance was obtained in 92,1% patients (82,1% in a single session). Overall, AEs occurred in 37(10%) cases.The grade of AEs was mild or moderate for all cases, except one which was fatal. CONCLUSION: D-SOC is effective for diagnostic and therapeutic indications.Most of the AEs were minor and managed conservatively, even though a fatal event has happened that is not negligible and should be considered before using D-SOC.

Prevalence of small intestinal bacterial overgrowth in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is associated with gastrointestinal motility abnormalities that could favor the occurrence of small intestinal bacterial overgrowth. The aim of the study was to assess the prevalence of small intestinal bacterial overgrowth in PD patients. METHODS: Consecutive PD patients were enrolled. The controls were subjects without PD. All patients and controls underwent the glucose breath test to assess small intestinal bacterial overgrowth. RESULTS: Forty-eight PD patients and 36 controls were enrolled. The prevalence of small intestinal bacterial overgrowth was significantly higher in PD patients than in controls (54.17% vs 8.33%; P < .0001; OR, 2.24; 95% CI, 3.50-48.24). Multivariate analysis showed Hoehn and Yahr stage (OR, 3.07; 95% CI, 1.14-8.27) and Unified PD Rating score (OR, 1.12; 95% CI, 1.02-1.23) were significantly associated with small intestinal bacterial overgrowth in PD patients. CONCLUSIONS: Small intestinal bacterial overgrowth is highly prevalent in PD. Gastrointestinal motility abnormalities might explain this association.

Gastrointestinal Complications after Allogeneic Hematopoietic Stem Cell Transplant: A Multidisciplinary Approach with Early Endoscopic Evaluation.

Gastrointestinal complications (GICs) represent the major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Differential diagnosis of GICs is of paramount importance since early and reliable identification of graft-versus-host disease (GVHD) is essential for a correct management of the patients. The aim of the present retrospective study was to evaluate the occurrence of GICs after allo-HSCT and to assess the diagnostic performance of a quick endoscopic and histological assessment in the differential diagnosis between GVHD and other GI conditions. Between January 2015 and August 2019, 122 consecutive patients receiving an allo-HSCT were managed by an interdisciplinary team, supported by a dedicated endoscopic service. Clinical, therapeutic, endoscopic and histological data were analyzed for each patient. Collectively, 94 of the patients developed GICs (77%). A moderate-severe mucositis was the most frequent complication, occurring in 79 patients (84%). Acute GI-GVHD was diagnosed in 35 patients (37% of whom with GICs) and 19 of them with a moderate-severe grade. Infective acute colitis developed in eight patients, mainly due to Clostridium difficile (CD) and Cytomegalovirus infections (8.5%). Rectal biopsy showed the highest sensitivity and specificity (80% and 100%, respectively). However, when biopsy procedures were guided by symptoms and performed on apparently intact mucosa, upper histology also provided a high negative predictive value (80%). Our multidisciplinary approach with a quick endoscopic/histologic investigation in the patients receiving an allo-HSCT and who suffered GICs could improve diagnostic and therapeutic management in this challenging setting.

Ethyl caffeate from Verdicchio wine: chromatographic purification and in vivo evaluation of its antifibrotic activity.

Ethyl caffeate (CfE, caffeic acid ethyl ester) was extracted from dealcoholized Verdicchio, a white wine from Marche (Italy) with ethyl acetate and then purified with semipreparative reversed-phase high-performance liquid chromatography (RP-HPLC) using an ODS2 column (25 cm x 20 mm id) at an isocratic flow of 5 mL/min (the mobile phase A was formic acid 4.5% in water and the mobile phase B was acetonitrile). The CfE extract administered intraperitoneally at 1 mumol/L in rats previously treated with 10 mg/kg dimethylnitrosamine was able to prevent the dimethylnitrosamine-induced loss in body and liver weight, as well as to reduce the degree of liver injury, as determined by alanine aminotransferase values and necroinflammatory score, after a 1-week treatment. This was associated with a reduced hepatic stellate cells activation (from 16.8 to 8.3% of smooth muscle actin positive parenchyma) and proliferation (from 11.3 to 5.5 cells/mm(2)). The collagen synthesis was also reduced: the percentage of Sirius Red positive parenchyma decreased from 21.7 to 7.2%. The CfE levels of Verdicchio wine determined with RP-HPLC-DAD were about 14 times the active levels tested in the in vivo test. CfE can be considered as a promising natural compound for future application in chronic liver disease.

Clinical and patient reported outcomes of the multidisciplinary management in patients with inflammatory bowel disease-associated spondyloarthritis.

OBJECTIVE: Arthritis is the most frequent extra-intestinal manifestation in patients with inflammatory bowel diseases (IBD). The coexistence of intestinal and articular inflammation advocates the need for a multidisciplinary management of patients with IBD-associated spondyloarthritis. METHODS: Consecutive IBD patients were evaluated jointly by the gastroenterologist and the rheumatologist in a combined clinic. All the patients were assessed and screened for articular involvement, disease activity and health related quality of life. After the prescription of a shared treatment, patients with spondyloarthritis were followed up for 24 months. RESULTS: Two hundred sixty-two IBD patients, including 80 who were classified as affected by spondyloarthritis according to the ASAS criteria, were included in the study. At baseline, patients with both IBD and spondyloarthritis showed worse quality of life in both the physical and mental domains. The multidisciplinary management provided a significant improvement of gastrointestinal and articular manifestations, as well as the health-related quality of life. Moreover, global and gastrointestinal-specific quality of life significantly correlated with articular disease activity. CONCLUSION: The multidisciplinary management significantly improves both articular and gastrointestinal disease activities and the quality of life of patients with IBD-associated spondyloarthritis. An appropriate screening strategy and the integrated management of these patients should be encouraged and employed in clinical practice.

Postoperative Recurrence of Crohn's Disease: Pathophysiology, Diagnosis and Treatment.

BACKGROUND: Abstract: Up to 80% of Crohn's disease (CD) patients require at least one surgical intervention in their lifetime and up to 70% of these patients develop postoperative endoscopic recurrence within 1 year. METHODS: The most important predictors of early postoperative recurrence are represented by smoking, prior intestinal surgery, penetrating disease and perianal location. Genetic factors, gut microbiota structure and immunological alterations may be involved in the pathogenesis of postoperative recurrence of CD, although their specific roles have to be determined yet. RESULTS: Different drugs, such as metronidazole, thiopurines and anti-tumor necrosis factor α (anti- TNFα) have been shown to reduce the risk of recurrence in many clinical trials, although the choice of the drug should take into consideration the benefits, the potential side effects and also the costs. Patients who are at high risk for postoperative recurrence should be considered for early medical prophylaxis with thiopurines or anti-TNFα drugs; on the contrary, patients who do not have risk factors may receive no treatment or receive a course of antibiotic or mesalazine followed by tailored therapy based on endoscopy at 6 months. CONCLUSION: Therefore, stratifying patients according to their risk of recurrence and tailoring therapy are at present the ideal and most cost-effective ways to treat operated CD patients, although many aspects require further evaluation.

Biologic Drugs in Crohn's Disease and Ulcerative Colitis: Safety Profile.

Ulcerative Colitis (UC) and Crohn's Disease (CD) are chronic, progressive and disabling disorders characterized by a heterogeneous clinical course. Some years ago the main goal of the therapy was to achieve and maintain clinical remission, whereas at present the main goal of therapy is represented by the deep remission, characterized by sustained clinical remission, complete mucosal healing and normalization of serological markers of inflammation. In the last years new therapeutic approaches have been introduced which have led to a reduction in the mortality rate and have modified the natural history of Inflammatory Bowel Diseases (IBD). In addition, several prognostic factors have been identified which have allowed to better stratify the disease and to choose the most appropriate therapy for the single patient. Moreover, early treatment with immunosuppressive drugs and/or biologics has changed, at least in the short term, the course of the disease by reducing hospitalization rate and the need for surgery. Therefore, the development of biologic therapies has represented an important step in the treatment of IBD, since these drugs induce remission and response rates that are not achieved by other therapies. Since their use can result in significant adverse events that increase morbidity, patients must be aware of the risks associated with treatment and must be strictly monitored. Although treatment with biologic drugs is not successful in all patients and many of them lose clinical response, new therapies are currently under evaluation.

Helicobacter pylori infection in psoriasis: results of a clinical study and review of the literature.

BACKGROUND: Data from the literature concerning the role of Helicobacter pylori (H. pylori) infection in psoriasis are still conflicting. This study was carried out to evaluate prevalence of H. pylori in patients with mild to severe psoriasis, correlation between H. pylori infection and severity of psoriasis, and effect of H. pylori eradication on the clinical course of psoriasis. METHODS: Two hundred and ten patients with psoriasis and 150 healthy controls were screened for H. pylori through [(13) C] urea breath test at baseline (T0). All patients with psoriasis received standardized phototherapy treatment, and those infected by H. pylori were also treated with a 1-week triple therapy, then they were all re-evaluated four weeks later at the end of therapy (T5). RESULTS: The prevalence of H. pylori was not higher in psoriasis than in the control group (20.27 vs. 22%; P > 0.05). Patients infected by H. pylori showed more severe psoriasis than uninfected patients (psoriasis area and severity index score 17.9 ± 7.1 vs. 13.7 ± 6.9; P = 0.04), and patients who received successful eradication of H. pylori infection showed a greater improvement of psoriasis than the others (psoriasis area and severity index score at T5 in patients infected by H. pylori was 8.36 ± 3.76, in uninfected patients was 10.85 ± 3.49; P = 0.006). CONCLUSIONS: Patients with mild to severe psoriasis do not show a greater prevalence of H. pylori infection; however, H. pylori seems able to affect the clinical severity of psoriasis.

The Novel Crohn's Disease Marker Anti-GP2 Antibody Is Associated with Ileocolonic Location of Disease.

Crohn's disease (CD) is an inflammatory bowel disease (IBD) that can affect the whole gastrointestinal tract. The ileocolonic variant of CD, an inflammation of both the ileum and the large intestine, accounts for up to 50% of the cases with CD, whereas Crohn's ileitis affecting the ileum is diagnosed in about 30%. Crohn's colitis, which is confined to the large intestine and accounts for the remaining 20%, is difficult to distinguish from the large bowel inflammation seen in patients with ulcerative colitis (UC). The pathogenesis of CD is not yet completely understood. Autoimmunity is one factor that can partake in the triggering or modulation of inflammatory processes in IBD. The major zymogen-granule membrane glycoprotein 2 (GP2) has been recently identified as a major autoantigenic target in CD. Interestingly, GP2 is mainly expressed in the pancreas and has also been demonstrated to be a membrane-anchored receptor of microfold cells in the follicle-associated epithelium. Remarkably, GP2 is overexpressed at the site of CD inflammation in contrast to the one in UC. By utilizing novel enzyme-linked immunosorbent assays for the detection of GP2-specific IgA and IgG, the loss of tolerance to GP2 has been associated with a specific clinical phenotype in CD, in particular with the ileocolonic location of the disease.

Selective Na+/H+ exchange inhibition by cariporide reduces liver fibrosis in the rat.

The aim of this study was to evaluate the effect of cariporide, a selective Na(+)/H(+) exchange inhibitor, on isolated and cultured hepatic stellate cells (HSCs) and in 2 in vivo models of rat liver fibrosis. Platelet-derived growth factor (PDGF)-induced HSC proliferation, evaluated by measuring the percentage of bromodeoxyuridine-positive cells, was significantly inhibited by cariporide, with a maximal effect at 10 micromol/L. Incubation with cariporide did not inhibit PDGF-induced extracellular-regulated kinase 1/2 (ERK1/2), Akt (a downstream component of the phosphatidylinositol [PI]-3 kinase pathway), and protein kinase C (PKC) activation but reduced PDGF-induced activation of the Na(+)/H(+) exchanger, with a maximal effect at 10 micromol/L. Rats treated with dimethylnitrosamine (DMN; 10 mg/kg) for 1 and 5 weeks received a diet with or without 6 ppm cariporide. Treatment with cariporide reduced the degree of liver injury, as determined by alanine aminotransferase (ALT) values, also when administered after the induction of hepatic damage. This was associated with reduced HSC activation and proliferation and reduced collagen deposition, as determined by morphometric evaluation of alpha-smooth muscle actin (SMA)/proliferating cell nuclear antigen-positive cells and percentage of Sirius red-positive parenchyma, respectively. Moreover, cariporide was also able to reduce alpha(1)I procollagen messenger RNA (mRNA) expression. Similar effects were observed in bile duct-ligated (BDL) rats. In conclusion, selective inhibition of the Na(+)/H(+) exchanger by cariporide may represent an effective therapeutic strategy in the treatment of hepatic fibrosis.

Rearrangement of the cytoskeletal network induced by platelet-derived growth factor in rat hepatic stellate cells: role of different intracellular signalling pathways.

BACKGROUND/AIMS: Cytoskeletal reorganization plays an important role in the regulation of different cell functions, such as proliferation and migration. Since platelet-derived growth factor (PDGF) stimulates both proliferation and chemotaxis of hepatic stellate cells (HSC), we investigated the effects of this cytokine on cytoskeletal components of cultured rat HSC. METHODS/RESULTS: Exposure of HSC to PDGF induced the formation of stress fibres and of a ruffled configuration of the plasma membrane, evaluated by both fluorescence and electron microscopy. These modifications were also induced by exposure to the protein kinase C (PKC) activator phorbol-12-myristate-13-acetate (PMA) and abolished by pretreatment with the PKC inhibitor calphostin C, with the Rho inhibitor C3 exoenzyme and with the intracellular calcium chelator MAPTAM, but not with the PI-3 kinase inhibitor wortmannin or with the mitogen-activated protein kinase kinase inhibitor PD 98059. PDGF induced a translocation of Rho from the cytosol to the membrane which was inhibited by C3 exoenzyme and by calpostin C, and which was also induced by PMA. Moreover, PDGF induced a rearrangement of vinculin which was prevented by C3 exoenzyme and calphostin C. CONCLUSIONS: PDGF-induced cytoskeletal reorganization in HSC is dependent on PKC and Rho, thus suggesting that these two pathways may play an important role in the response of liver to injury.

Effect of pirfenidone on rat hepatic stellate cell proliferation and collagen production.

BACKGROUND/AIMS: Pirfenidone has been recently shown to reduce dimethynitrosamine-induced liver fibrosis in the rat, but no information are available on the effect of this drug on cultured hepatic stellate cells (HSC). METHODS: HSC proliferation was evaluated by measuring bromodeoxyuridine incorporation; PDGF-receptor autophosphorylation, extracellular signal-regulated kinase (ERK1/2) and pp70(S6K) activation were evaluated by western blot; protein kinase C activation was evaluated by western blot and by ELISA; type I collagen accumulation and alpha1(I) procollagen mRNA expression were evaluated by ELISA and northern blot, respectively. RESULTS: Pirfenidone significantly inhibited PDGF-induced HSC proliferation, starting at a concentration of 1 microM, with a maximal effect at 1000 microM, without affecting HSC viability and without inducing apoptosis. The inhibition of PDGF-induced HSC proliferation was associated neither with variations in PDGF-receptor autophosphorylation, or with ERK1/2 and pp70(S6K) activation. On the other hand, pirfenidone was able to inhibit PDGF-induced activation of the Na(+)/H(+) exchanger, which is involved in PDGF-induced HSC proliferation in HSC, with a maximal effect at 1000 microM and inhibited PDGF-induced protein kinase C activation. Pirfenidone 100 and 1000 microM inhibited type I collagen accumulation in the culture medium induced by transforming growth factor(beta1) by 54% and 92%, respectively, as well as TGF(beta1)-induced alpha1(I) procollagen mRNA expression. RESULTS: Pirfenidone could be a new candidate for antifibrotic therapy in chronic liver diseases.