Francisco Colina

Uric acid and anti-TNF antibody improve mitochondrial dysfunction in ob/ob mice.

The mechanisms responsible for low mitochondrial respiratory chain (MRC) activity in the liver of patients with nonalcoholic steatohepatitis are unknown. In this study, we examined the cause of this dysfunction in ob/ob mice. Forty‐six mice were distributed in six groups: group I: C57BL/6J mice; group II: C57BL/6J Lep(−/−) mice (ob/ob); group III, ob/ob mice treated with manganese [III] tetrakis (5,10,15,20 benzoic acid) porphyrin (MnTBAP); group IV, ob/ob mice treated with IgG1 immunoglobulin; group V, ob/ob mice treated with anti‐TNF antibody; group VI: ob/ob mice treated with uric acid. In liver tissue, we measured MRC activity, fatty acid β‐oxidation, tumor necrosis factor (TNF), inducible nitric oxide synthase (iNOS), 3‐tyrosine‐nitrated proteins, 3‐tyrosine‐nitrated mitochondrial proteins, including cytochrome c and ND4 subunit of complex I. MRC activity was decreased in ob/ob mice. TNF levels, iNOS protein expression, and tyrosine nitrated proteins were markedly increased in the liver of ob/ob mice. In these animals, mitochondrial proteins were markedly tyrosine nitrated, particularly the ND4 subunit of complex I and cytochrome c. Treatment of these animals with uric acid, a peroxynitrite scavenger, anti‐TNF antibody, or MnTBAP decreased tyrosine nitrated proteins, improved the activity of MRC complexes, and led to a marked regression of hepatic steatosis and inflammation. In conclusion, MRC dysfunction and liver lesions found in ob/ob mice are likely to reflect the tyrosine nitration of mitochondrial proteins by peroxynitrite or a peroxynitrite‐derivate radical. Increased hepatic TNF and iNOS expression might enhance peroxynitrite formation and inhibition of MRC complexes. (HEPATOLOGY 2006;44:581–591.)

A pilot trial of fenofibrate for the treatment of non-alcoholic fatty liver disease

BACKGROUND Dyslipidaemia and insulin resistance are two important risk factors for non-alcoholic fatty liver disease. Both factors can improve with fenofibrate. AIMS To evaluate the effect of fenofibrate on the clinical, analytical and histological evolution of patients with non-alcoholic fatty liver disease. SUBJECTS AND METHODS Sixteen consecutive patients with biopsy-confirmed non-alcoholic fatty liver disease were treated with 200mg/day of fenofibrate for 48 weeks. A clinical and biochemical follow-up was done every 3 months. A new liver biopsy was performed in all patients at the end of therapy. RESULTS All patients completed 48 weeks of therapy with fenofibrate, without adverse events. At the end of the study, a significant decrease in triglyceride, glucose, alkaline phosphatase and gamma-glutamyl transpeptidase and an increase of apolipoprotein A1 levels were found. Insulin levels and insulin resistance showed a trend to decrease. Moreover, a reduction in the proportion of patients with abnormal aminotransferase levels (>45IU/L) was observed (alanine aminotransferase: 93.7% vs. 62.5%, p=0.02; aspartate aminotransferase: 50% vs. 18.7%, p=0.02). The body mass index did not show any significant change, but the proportion of patients with metabolic syndrome decreased significantly (43.7% vs. 18.7%, p=0.04). A control biopsy after treatment revealed a decrease in the grade of hepatocellular ballooning degeneration (p=0.03), but the grade of steatosis, lobular inflammation, fibrosis or non-alcoholic fatty liver disease activity score did not change significantly. CONCLUSIONS In patients with non-alcoholic fatty liver disease, treatment with fenofibrate is safe and improves metabolic syndrome, glucose and liver tests. However, its effects on liver histology are minimal.

Clinical and histological efficacy of pegylated interferon and ribavirin therapy of recurrent hepatitis C after liver transplantation

Treatment of recurrent hepatitis C in liver transplant is controversial. The aim of our study was to evaluate the clinical and histological efficacy of pegylated interferon alpha 2b (PEG‐IFN) and ribavirin therapy of recurrent hepatitis C after liver transplantation (LT). We prospectively included 47 liver transplant patients with: 1) a positive test for hepatitis C virus (HCV)‐ribonucleic acid (RNA) in serum; 2) alanine aminotransferase (ALT) >45 UI/mL; and 3) a liver biopsy showing chronic hepatitis without rejection in the previous 2 months. Patients received PEG‐IFN (1.5 μg/kg/week) and ribavirin (800‐1,000 mg/day) for 12 months. Follow‐up was based on biochemical (ALT), virological (RNA‐HCV), and histological (liver biopsy) examinations. Follow‐up lasted a minimum of 6 months after the end of antiviral therapy. Sustained virological response (SVR) was achieved in 23% of the patients. A total of 33 (70%) patients had normalized ALT levels at the end of therapy. Inflammatory portal and lobular score declined significantly in patients with SVR (P < 0.05) but not in nonresponder patients. Fibrosis did not change significantly in either group. SVR was significantly associated with low γ‐glutamyltransferase GGT (P = 0.04) and HCV‐RNA levels (P = 0.03), a virological response at 12 weeks (P = 0.002) and patients compliance (P = 0.04). Ten (21%) patients were withdrawn prematurely due to adverse effects. In conclusion, Therapy with PEG‐IFN and ribavirin achieved SVR and a significant histological improvement in 23% of liver transplant recipients with chronic hepatitis C. Toxicity is an important drawback of this therapy. Liver Transpl 12:1805‐1812, 2006.

Steroid withdrawal is safe and beneficial in stable cyclosporine-treated liver transplant patients

BACKGROUND In the immunosuppression of orthotopic liver transplant recipients, steroids are used despite their unspecific action and long-term side effects. Few studies have been carried out on steroid withdrawal and many aspects remain to be elucidated. METHODS A prospective study was performed to analyse the effect of steroid withdrawal on 86 patients with stable graft function, more than 1 year after orthotopic liver transplant. Thirty patients had chronic hepatitis in the graft. Seventy-two continued with cyclosporine (CsA) and 14 with CsA-azathioprine (AZA) therapy. The follow-up was 23.2 +/- 8.1 months (range 12-52 months). A paired t-test was used for statistical analysis. RESULTS No acute or chronic rejection occurred, and steroids were not reinstituted. There were no changes in serum transaminase levels, but bilirubin levels decreased (p < 0.01). At the end of the follow-up, we found improvements in blood pressure in hypertensive patients (systolic 156.1 +/- 8.4 mmHg vs. 139.4 +/- 8.7 mmHg, p < 0.001); body weight (72 +/- 13.5 kg vs. 70.8 +/- 13 kg, p < 0.05); serum cholesterol (211.3 +/- 42 mg/dl vs. 191.6 +/- 43.5 mg/dl, p < 0.001) and bone mineral density in lumbar spine (0.823 +/- 0.13 g/cm2 vs. 0.893 +/- 0.135 g/cm2, p < 0.001). Four of ten diabetic patients were no longer insulin-dependent and insulin requirements decreased in the remaining six. No significant biochemical changes were found in patients with hepatitis in the graft, and we found an improvement in inflammatory activity in the nine biopsied patients. CONCLUSIONS Steroid withdrawal with CsA monotherapy is feasible, safe and beneficial in patients who have stable liver graft function 1 year after orthotopic liver transplant. We consider that AZA therapy is not necessary unless drastic reduction of CsA levels is required because of renal dysfunction.

Malignant lymphoma of Jejunum with common variable hypogammaglobulinemia and diffuse nodular hyperplasia of the small intestine : a case study and literature review

We report a patient with common variable hypogammaglobulinemia and diffuse nodular lymphoid hyperplasia of the small intestine complicated by a jejunal malignant lymphoma. Immunopathological and histological studies showed a polymorphous centroblastic lymphoma with intracytoplasmatic IgM immunoglobulin and lambda light chains. Some mucosal nodules separate from the tumor mass showed atypical lymphoid cell populations similar to lymphoma cells, suggesting a transition between hyperplastic nodules and lymphoma nodules. Four similar cases, and six other patients with malignant lymphoma of the small intestine, associated with diffuse nodular lymphoid hyperplasia, but without immunodeficiency, have already been described. All these cases suggest that nodular lymphoid hyperplasia increases the risk of small intestine lymphoma.

Antimitochondrial antibody-negative chronic nonsuppurative destructive cholangitis. Atypical primary biliary cirrhosis or autoimmune cholangitis?

We investigated whether autoimmune cholangitis (AC) has specific features that constitute an entity other than primary biliary cirrhosis (PBC). We compared clinical, laboratory, and liver biopsy features; response to treatment; and the follow-up of two groups of patients. The first group comprised seven patients with AC criteria-PBC with negative antimitochondrial antibodies (AMAs) and positive antinuclear antibodies (ANAs)-termed the PBC AMA-negative group; the second was made up of another seven PBC patients with positive AMA, labeled the PBC AMA-positive group. We found that the PBC AMA-negative group had, besides negative AMAs and positive ANAs, a significantly higher incidence of asthenia, a higher and earlier incidence of liver failure, and higher ANA titers and serum immunoglobulin G levels than the PBC AMA-positive group. There were no significant differences in the other laboratory tests, although the PBC AMA-negative group showed higher serum bilirubin and aminotransferase and lower serum alkaline phosphatase and immunoglobulin M levels. Liver histological data were similar in both groups. Patients in the PBC AMA-negative group, with more markedly abnormal liver tests, responded to immunosuppressive therapy. We concluded that patients with criteria for PBC but with negative AMAs and positive ANAs have a few specific features that fall between PBC and autoimmune chronic hepatitis. This finding suggests that these patients have a different disease, for which autoimmune cholangitis seems to be an appropriate name.

High-fat diet decreases activity of the oxidative phosphorylation complexes and causes nonalcoholic steatohepatitis in mice.

Nonalcoholic fatty liver disease (NAFLD) is the most frequent histological finding in individuals with abnormal liver-function tests in the Western countries. In previous studies, we have shown that oxidative phosphorylation (OXPHOS) is decreased in individuals with NAFLD, but the cause of this mitochondrial dysfunction remains uncertain. The aims of this study were to determine whether feeding mice a high-fat diet (HFD) induces any change in the activity of OXPHOS, and to investigate the mechanisms involved in the pathogenesis of this defect. To that end, 30 mice were distributed between five groups: control mice fed a standard diet, and mice on a HFD and treated with saline solution, melatonin (an antioxidant), MnTBAP (a superoxide dismutase analog) or uric acid (a scavenger of peroxynitrite) for 28 weeks intraperitoneously. In the liver of these mice, we studied histology, activity and assembly of OXPHOS complexes, levels of subunits of these complexes, gene expression of these subunits, oxidative and nitrosative stress, and oxidative DNA damage. In HFD-fed mice, we found nonalcoholic steatohepatitis, increased gene expression of TNFα, IFNγ, MCP-1, caspase-3, TGFβ1 and collagen α1(I), and increased levels of 3-tyrosine nitrated proteins. The activity and assembly of all OXPHOS complexes was decreased to about 50–60%. The amount of all studied OXPHOS subunits was markedly decreased, particularly the mitochondrial-DNA-encoded subunits. Gene expression of mitochondrial-DNA-encoded subunits was decreased to about 60% of control. There was oxidative damage to mitochondrial DNA but not to genomic DNA. Treatment of HFD-fed mice with melatonin, MnTBAP or uric acid prevented all changes observed in untreated HFD-fed mice. We conclude that a HFD decreased OXPHOS enzymatic activity owing to a decreased amount of fully assembled complexes caused by a reduced synthesis of their subunits. Antioxidants and antiperoxynitrites prevented all of these changes, suggesting that nitro-oxidative stress played a key role in the pathogenesis of these alterations. Treatment with these agents might prevent the development of NAFLD in humans.

Etiopathogenesis and prognosis of centrilobular necrosis in hepatic grafts

The incidence, contributing etiopathogenetic factors, and prognostic significance of centrilobular necrosis were investigated in 270 hepatic transplants to 215 immunosuppressed patients in whom 837 biopsies were performed. Twenty-six (9.6%) grafts demonstrated centrilobular necrosis in one or more biopsy specimens. The immunological, clinical, histopathological, and evolutionary features of this patient group (group A) were compared with a control group of patients who had undergone 92 consecutive transplants with no necrosis (group B). Group A was younger (p < 0.01), had a higher average of warm and cold-ischemia time (p < 0.05), a higher incidence (p < 0.001) and earlier appearance of acute rejection episodes (p < 0.01), and a closer association with evolution to chronic rejection (A: 53.8% vs B: 13.1%, p < 0.001). Survival rates for grafts and patients with necrosis at 12 and 30 months were significantly lower (p < 0.001). The 26 grafts were distributed into three chronological subgroups according to when necrosis appeared: (1) First week--All these grafts were lost (four through primary graft nonfunction and one due to protal recurrent thrombosis); (2) Second week--seven grafts with associated acute rejection, with three evolving to chronic rejection; (3) After the second week (116 +/- 82 days)--five with isolated necrosis, two with associated acute rejection, four with associated ductopenia, and three with associated acute rejection and ductopenia. In 11 grafts the necrosis persisted and evolved to chronic rejection. In conclusion, these findings indicate that centrilobular necrosis is a histopathological sign associated with poor prognosis in most hepatic grafts.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus-related fibrosing cholestatic hepatitis after cardiac transplantation: is azathioprine a contributory factor?

We report a patient who acquired hepatitis C virus (HCV) infection at cardiac transplantation, developing fibrosing cholestatic hepatitis (FCH) with early liver failure and a fatal outcome. FCH is a recently described clinicopathological entity characterized by a cholestatic pattern of serum liver enzyme abnormalities, a progressive course leading to liver failure, and a pathological picture defined by periportal fibrosis, neutrophilic infiltrates and signs of histological cholestasis. Although it was initially described secondary to hepatitis B virus infection, it has also been recently related to HCV infection. Some histopathological features consistent with azathioprine hepatotoxicity like cholestasis, perisinusoidal fibrosis, veno-subocclusive lesions and nodular regenerative hyperplasia were also observed in this case. Therefore, a direct cytopathic effect of HCV and the concurrent pathogenic role of azathioprine hepatotoxicity may be involved in the development of this complication of transplantation.

Porphyria cutanea tarda as a Predictor of Poor Response to Interferon Alfa Therapy in Chronic Hepatitis C

Background: Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-a) in the treatment of patients with chronic hepatitis C and PCT. Methods: We treated a total of 66 patients with chronic hepatitis C with IFN-a 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown. Results: Sustained virologie response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status. Conclusion: Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNa therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNa treatment.