Hepatic regeneration. Effects of age, sex hormone status, prolactin, and cyclosporine

Acetaminophen dose does not predict outcome in acetaminophen-induced acute liver failure

BACKGROUND

Acetaminophen is a dose-dependent toxin. Prognosis in severe acute liver injury is related presumably in part to the dose ingested. We sought to assess the value of acetaminophen dosing information in patients with acute liver failure (ALF) due to acetaminophen toxicity to determine the role of dose as a prognostic indicator.

METHODS

Prospective data from 113 patients with ALF having single-time-point ingestions of acetaminophen were analyzed. Multivariate and chi tests were used to determine the relationship of dose to clinical outcome. We also used the Mann-Whitney U test to compare prognosis and survival in ALF with acetaminophen dose ingested.

RESULTS

Multivariate and chi analyses failed to show any relationship between acetaminophen dose and spontaneous survival. A separate analysis showed no correlation between acetaminophen dose and clinical prognostic indicators.

CONCLUSIONS

Dose of acetaminophen ingested did not seem to play a role in prognosis. The most important prognostic factor was coma grade on admission to study. Acetaminophen dosing information is not always obtainable. When it is, it adds little to the clinical assessment. Severity of encephalopathy is a more reliable indicator of prognosis in these critically ill patients.

The therapeutic potential of human umbilical mesenchymal stem cells from Wharton's jelly in the treatment of rat liver fibrosis

We investigated the effect of human umbilical mesenchymal stem cells (HUMSCs) from Wharton's jelly on carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Rats were treated with CCl4 for 4 weeks, and this was followed by a direct injection of HUMSCs into their livers. After 4 more weeks of CCl4 treatment (8 weeks in all), rats with HUMSC transplants [CCl4 (8W)+HUMSC liver] exhibited a significant reduction in liver fibrosis, as evidenced by Sirius red staining and a collagen content assay, in comparison with rats treated with CCl4 for 8 weeks without HUMSC transplants [CCl4 (8W)]. Moreover, rats in the CCl4 (8W)+HUMSC (liver) group had significantly lower levels of serum glutamic oxaloacetic transaminase, glutamic pyruvate transaminase, alpha-smooth muscle actin, and transforming growth factor-beta1 in the liver, whereas the expression of hepatic mesenchymal epithelial transition factor-phosphorylated type (Met-P) and hepatocyte growth factor was up-regulated, in comparison with the CCl4 (8W) group. Notably, engrafted HUMSCs scattered mostly in the hepatic connective tissue but did not differentiate into hepatocytes expressing human albumin or alpha-fetoprotein. Instead, these engrafted, undifferentiated HUMSCs secreted a variety of bioactive cytokines that may restore liver function and promote regeneration. Human cytokine assay revealed that the amounts of human cutaneous T cell-attracting chemokine, leukemia inhibitory factor, and prolactin were substantially greater in the livers of the CCl4 (8W)+HUMSC (liver) group, with considerably reduced hepatic inflammation manifested by a micro positron emission tomography scan. Our findings suggest that xenogeneic transplantation of HUMSCs is a novel approach for treating liver fibrosis and may be a promising therapeutic intervention in the future.

Natural history of hepatic fibrosis progression in chronic hepatitis C virus infection in India

BACKGROUND AND AIM

The rate of fibrosis progression per year can predict the time for the development of cirrhosis in chronic hepatitis C (CHC). We assessed the rate of fibrosis progression and the predictors of disease severity in Indian CHC patients.

METHODS

Of the 355 treatment-naïve, histologically-proven CHC patients, the precise duration of infection (from the time of exposure to HCV until liver biopsy) could be determined in 213 patients (age = 41.6 +/- 14.7 years, male : female = 139 : 74, genotype 3 = 75%). The rate of fibrosis progression per year was calculated. The correlation of the advanced degree of fibrosis and age, duration of infection, age at the onset of infection, sex, mode of infection, hepatitis C virus (HCV) genotype, histological activity index (HAI), and the presence of diabetes mellitus were studied.

RESULTS

The median rate of fibrosis progression per year was 0.25 (0.0-1.5) fibrosis units. The fibrosis progression rate was higher in patients who acquired infection at > 30 years of age, those < 30 years (0.33 vs 0.15; P < 0.001), and those who acquired HCV infection with a history of blood transfusion than with other modes of transmission (0.25 vs 0.19; P = 0.04). The median time to progress to cirrhosis was 16 years. The multivariate analysis found that the HAI score (odds ratio [OR]= 14.03; P < 0.001) and the duration of infection > 10 years (OR = 4.83; P < 0.001) correlated with severe liver disease (fibrosis > or = 3).

CONCLUSION

The median rate of fibrosis progression per year in Indian CHC patients is 0.25 fibrosis units. A higher HAI and longer duration of infection are associated with a significant risk of advanced liver disease, and merit early therapeutic interventions.

Effect of prolactin on release of selected enzymes from the isolated rabbit liver

This report analyzes the effect of prolactin (PRL) on ALT and AST release from the rabbit liver into the preservation solution. Dissected and perfused livers were stored for 24 hours in Ringer's solution without (control group) or with PRL (experimental group). During the organ preservation, sample of the solution were obtained at 1, 8, 12, 16, 18, and 24 hours. It was found that PRL added to Ringer's solution significantly decreased the quantity and rate of released ALT (P < .081) and AST (P < .029) from the preserved liver. ALT was released 2.51 times more slowly (kappa = -0.03329 [h(-1)]) and AST 3.43 times more slowly (kappa = -0.08356 [h(-1)]) into Ringer's solution with PRL. The experimental group showed maintenance of the value of the de Ritis index at a stable level between 2.0-3.0. In conclusion, PRL added to a preservation solution significantly decreased the quantity and slowed the release rate of ALT and AST aminotransferases from the preserved rabbit liver, implying that this hormone has hepatoprotective properties.

The influence of host factors on the natural history of chronic hepatitis C viral infections

The natural history of hepatitis C is variable, with some patients progressing rapidly to cirrhosis and others showing no significant fibrosis over many decades. A number of studies have examined the factors that influence disease progression. Age at time of infection, gender, alcohol abuse and, perhaps, route of transmission, appear to have the greatest influence on the natural history of the hepatitis C virus with the possible exception of alcohol, the mechanism whereby these factors influence disease progression has yet to be determined.

Increases in the mitochondrial DNA replication and transcription in the remnant liver of rats

We studied mitochondrial DNA (mtDNA) replication and transcription in association with major hepatectomy. Changes in nuclear respiratory factor 1 (NRF-1) mRNA and RNA moiety of mitochondrial RNA-processing endoribonuclease (MRP-RNase RNA) were followed at 0, 3, 6, 12, and 24 h after hepatectomy. Contents of mtDNA, cytochrome b mRNA, and beta-actin mRNA were also measured. Contents of NRF-1 mRNA and MRP-RNase RNA increased to maximum or sub-maximum level 1 h after hepatectomy. mtDNA and cytochrome b mRNA increased to maximum level 3 h after. On the contrary, content of beta-actin mRNA increased to maximum level 12 h after. From these results, mtDNA replication and transcription occurred in the initial phase of liver regeneration, which might lead to an increase in mitochondrial respiratory function in the remnant liver, and cytoskeleton proteins such as beta-actin were followed thereafter.

Endocrine treatment of hepatocellular carcinoma. Any evidence of benefit?

In the past 20 years, a number of studies have investigated the relationship between sex hormones and liver cancer. Experimental studies indicate that a dynamic process, with sequential modifications in the pattern of sex hormones in the serum and of sex hormone receptors in the liver, occurs progressively during hepatocarcinogenesis. Overall, it seems that both androgens and oestrogens may enhance liver carcinogenesis, while androgens may also support the growth of established liver tumours. Unfortunately, clinical studies of endocrine treatment of hepatocellular carcinoma (HCC) have not adequately tested the suggestions from biological studies. So far, no clinical trial has been performed to test the efficacy of endocrine manipulation for the chemoprevention of HCC in cirrhotic patients nor in preventing relapse after radical resection of primary HCC. Anti-oestrogens have been the most studied agents for the endocrine treatment of established HCC, although the rationale that supports their use is weaker than for anti-androgens. Studies with anti-androgens have produced prevalently negative results, due to either a lack of activity or excessive toxicity. The use of chemical castration, which theoretically could enhance the activity of antihormonal compounds, yielded no benefit at all. In summary, there is, as yet, no definitive evidence that endocrine treatment favourably affects the outcome of patients with HCC.

Auxiliary partial orthotopic liver transplantation for fulminant hepatitis. The Paul Brousse experience

OBJECTIVE

The authors objective is to report their experience with auxiliary partial orthotopic liver transplantation in fulminant hepatitis (FH) and to discuss the principles that may help in its safe application.

SUMMARY BACKGROUND DATA

Auxiliary partial orthotopic liver transplantation is an attractive therapeutic method in FH because it provides hepatic function, whereas the remaining native liver is given the possibility to recover. Despite early encouraging reports, its place in the treatment of FH remains to be defined.

METHODS

Evaluation of 5 cases of FH treated with auxiliary partial orthotopic liver transplantation from a collective of 22 transplantations for 35 cases of FH referred to the authors' center from January 1994 to November 1995. The grafts were one left lobe, two left livers, and two right livers.

RESULTS

The native liver regenerated in three patients: one with Reye's syndrome who died of irreversible neurologic damage, one with FH caused by the hepatitis B virus who is alive 20 months after ABO incompatible graft removal, and one with FH caused by the hepatitis A virus who had her graft removed at 4 months. In two patients, regeneration did not occur: one with drug-induced FH who died of sepsis 3 months after surgery and one with FH of unknown origin who was retransplanted with a standard liver transplantation at 4 months for uncontrollable biliary rejection of an ABO incompatible graft (alive at 10 months). Two of the three patients who survived suffered severe neurologic complications.

CONCLUSIONS

Auxiliary partial orthotopic liver transplantation is an attractive treatment for FH, especially in the presence of good prognostic factors for native liver regeneration: a young patient, rapid onset of the disease, and viral hepatitis. It should be considered cautiously in patients with advanced encephalopathy. By providing a smaller mass of liver tissue than with standard orthotopic liver transplantation, and as a more complex operative procedure, auxiliary partial orthotopic liver transplantation may not be as effective in arresting the progression of neurologic damage.

Correlation between rat liver regeneration and mitochondrial energy metabolism

The time course of changes in mitochondrial energy metabolism during liver regeneration, following partial hepatectomy, is analyzed. For 24 h after surgical operation, a lag phase in the time course of the growth of liver is observed. In this period mitochondria showed a decrease of: (1) the respiratory control index; (2) the rate of oxidative phosphorylation; (3) the amount of immunodetected beta-F1 and F01-PVP subunits of F0F1-ATP synthase. No decrease, but instead a small increase in the content of mRNA for beta-F1 was observed in this phase. After this lag phase the growth of liver started, the content of mRNA for beta F1, as well as the level of immunodetected mitochondrial beta-F1 and F01-PVP subunits, increased and oxidative phosphorylation recovered. Analysis of the relative beta F1 protein/mRNA ratio indicates a decrease of beta F1 translational efficiency which remained low up to 72 h after partial hepatectomy and reached the same ratio of control at 96 h. It is concluded that the regenerating capability of rat liver is correlated with the efficiency of oxidative phosphorylation.

Increased risk of hepatocellular carcinoma development in patients with cirrhosis and with high hepatocellular proliferation

The immunohistochemical determination of the accessory protein of DNA-polymerase delta (PCNA), a marker of an early S-phase of the cell cycle, was used to evaluate cell proliferation retrospectively in formalin-fixed, paraffin-embedded liver biopsy sections in a group of patients with cirrhosis of similar age and duration of follow up, and with no evidence of hepatocellular carcinoma (41), including 17 patients with and 24 without hepatocellular carcinoma appearance during follow up. Proliferation was expressed as total (PCNA-TOT) and strongly (PCNA-STRO) positive nuclei per 1000 hepatocytes. The presence of dysplasia was also recorded. Histological findings and biochemical data, at the time of liver biopsy, were compared in the two groups. While total PCNA positivities were not significantly different in the two groups, strong reactivity was significantly higher in patients who eventually developed hepato-cellular carcinoma (median 0.7 vs 2.6). Univariate analysis of histological and biochemical data at the time of biopsy, followed by a stepwise regression study, showed that the significant parameters for a time-dependent disease-free state were, in decreasing order: cholesterol, PCNA-STRO, PCNA-TOT and alpha foeto-protein. Other clinical, biochemical and histological parameters, including dysplasia, provided no further information. From these data, hepatocellular proliferation can be evaluated in patients with cirrhosis with a currently available technique. Patients with high cell proliferation are at increased risk of developing hepatocellular carcinoma and may require differentiated follow up.