Non-invasive and invasive brain stimulation in alcohol use disorders: A critical review of selected human evidence and methodological considerations to guide future research

INTRODUCTION

Alcohol use disorder (AUD) ranks among the leading causes of decrements in disability-adjusted life-years. Long-term exposure to alcohol leads to an imbalance of activity between frontal cortical systems and the striatum, thereby enhancing impulsive behaviours and weakening inhibitory control. Alternative therapeutic approaches such as non-invasive and invasive brain stimulation have gained some momentum in the field of addictology by capitalizing on their ability to target specific anatomical structures and correct abnormalities in dysfunctional brain circuits.

MATERIALS AND METHODS

The current review, covers original peer-reviewed published research on the use of brain stimulation methods for the rehabilitation of AUD. A broad and systematic search was carried out on four electronic databases: NCBI PubMed, Web of Science, Handbooks and the Cochrane Library. Any original article in English or French language, without restrictions of patient age or gender, article type and publication outlet, were included in the final pool of selected studies.

RESULTS

The outcomes of this systematic review suggest that the dorsolateral prefrontral cortex (DLPFC) is a promising target for treating AUD with high frequency repetitive transcranial magnetic stimulation. Such effect would reduce feelings of craving by enhancing cognitive control and modulating striatal function. Existing literature also supports the notion that changes of DLPFC activity driven by transcranial direct current stimulation, could decrease alcohol craving and consumption. However, to date, no major differences have been found between the efficacy of these two non-invasive brain-stimulation approaches, which require further confirmation. In contrast, beneficial stronger evidence supports an impact of deep brain stimulation reducing craving and improving quality of life in AUD, effects that would be mediated by an impact on the nucleus accumbens, a central structure of the brain's reward circuitry. Overall, neurostimulation shows promise contributing to the treatment of AUD. Nonetheless, progress has been limited by a number of factors such as the low number of controlled randomized trials, small sample sizes, variety of stimulation parameters precluding comparability and incomplete or questionable sham-conditions. Additionally, a lack of data concerning clinical impact on the severity of AUD or craving and the short follow up periods precluding and accurate estimation of effect duration after discontinuing the treatment, has also limited the clinical relevance of final outcomes.

CONCLUSION

Brain stimulation remains a promising approach to contribute to AUD therapy, co-adjuvant of more conventional procedures. However, a stronger therapeutic rational based on solid physio-pathological evidence and accurate estimates of efficacy, are still required to achieve further therapeutic success and expand clinical use.

Impact of hepatitis C virus and alcohol, alone and combined, on the unfolded protein response in primary human hepatocytes

Hepatitis C virus (HCV) infection and alcohol abuse are leading causes of chronic liver disease and frequently coexist in patients. The unfolded protein response (UPR), a cellular stress response ranging along a spectrum from cytoprotection to apoptosis commitment, has emerged as a major contributor to human diseases including liver injuries. However, the literature contains conflicting reports as to whether HCV and ethanol activate the UPR and which UPR genes are involved. Here we have used primary human hepatocytes (PHH) to reassess this issue and address combined impacts. In this physiologically relevant model, either stressor activated a chronic complete UPR. However, the levels of UPR gene induction were only modest in the case of HCV infection. Moreover, when combined to the strong stressor thapsigargin, ethanol exacerbated the activation of pro-apoptotic genes whereas HCV tended to limit the induction of key UPR genes. The UPR resulting from HCV plus ethanol was comparable to that induced by ethanol alone with the notable exception of three pro-survival genes the expressions of which were selectively enhanced by HCV. Interestingly, HCV genome replication was maintained at similar levels in PHH exposed to ethanol. In conclusion, while both HCV and alcohol activate the hepatocellular UPR, only HCV manipulates UPR signalling in the direction of a cytoprotective response, which appears as a viral strategy to spare its own replication.

Evaluation of laboratory tests for cirrhosis and for alcohol use, in the context of alcoholic cirrhosis

Laboratory tests can play an important role in assessment of alcoholic patients, including for evaluation of liver damage and as markers of alcohol intake. Evidence on test performance should lead to better selection of appropriate tests and improved interpretation of results. We compared laboratory test results from 1578 patients between cases (with alcoholic cirrhosis; 753 men, 243 women) and controls (with equivalent lifetime alcohol intake but no liver disease; 439 men, 143 women). Comparisons were also made between 631 cases who had reportedly been abstinent from alcohol for over 60 days and 364 who had not. ROC curve analysis was used to estimate and compare tests' ability to distinguish patients with and without cirrhosis, and abstinent and drinking cases. The best tests for presence of cirrhosis were INR and bilirubin, with areas under the ROC curve (AUCs) of 0.91 ± 0.01 and 0.88 ± 0.01, respectively. Confining analysis to patients with no current or previous ascites gave AUCs of 0.88 ± 0.01 for INR and 0.85 ± 0.01 for bilirubin. GGT and AST showed discrimination between abstinence and recent drinking in patients with cirrhosis, including those without ascites, when appropriate (and for GGT, sex-specific) limits were used. For AST, a cut-off limit of 85 units/L gave 90% specificity and 37% sensitivity. For GGT, cut-off limits of 288 units/L in men and 138 units/L in women gave 90% specificity for both and 40% sensitivity in men, 63% sensitivity in women. INR and bilirubin show the best separation between patients with alcoholic cirrhosis (with or without ascites) and control patients with similar lifetime alcohol exposure. Although AST and GGT are substantially increased by liver disease, they can give useful information on recent alcohol intake in patients with alcoholic cirrhosis when appropriate cut-off limits are used.

Hepatitis delta virus super-infection in a co-infected patient with the human immunodeficiency virus type 1 and a surface antigen-negative hepatitis B virus variant

Human immunodeficiency virus infection has a major impact on the natural history of chronic hepatitis B and favours the emergence of viral mutants. We describe an acute hepatitis D virus superinfection in an HIV-1-infected patient under HAART treatment who was previously a chronic carrier of a surface negative HBV variant resistant to lamivudine.

Subjective parameters markedly limit the referral of transplantation candidates to liver transplant centres

BACKGROUND & AIMS

Equality of access to organ transplantation is a mandatory public health requirement. Referral from a local to a university hospital and then registration on the national waiting list are the two key steps enabling access to liver transplantation (LT). Although the latter procedure is well defined using the Model for End-stage Liver Disease score that improves equality of access, the former is mostly reliant on the practices of referring physicians. The aim of this study was to clarify the factors determining this initial step.

METHODS

This observational study included consecutive inpatients with cirrhosis of whatever origin in a cohort constituted between 2003 and 2008, using medical records and structured questionnaires concerning patient characteristics and the opinions of hospital clinicians. Candidates for LT were defined in line with these opinions.

RESULTS

Four hundred and thirty-three patients, mostly affected by alcoholic cirrhosis, were included, 21.0% of whom were considered to be candidates for LT. Factors independently associated with their candidature were: physician empathy [odds ratio (OR) = 10.8; 95% CI: 4.0-29.5], adherence to treatment (OR = 16.6; 95% CI: 3.7-75.2), geographical area (OR = 6.8; 95% CI: 2.2-21.3) and the patient's physiological age (OR = 2.3; 95% CI: 1.1-4.7).

CONCLUSIONS

Several subjective markers restrict the referral of patients from local hospitals to liver transplant centres. Their advancement to this second step is thus markedly weakened by initial subjectivity. The development of objective guidelines for local hospital physicians to assist them with their initial decision-making on LT is now necessary.

Quality indicators for colonoscopy procedures: a prospective multicentre method for endoscopy units

Background and Aims

Healthcare professionals are required to conduct quality control of endoscopy procedures, and yet there is no standardised method for assessing quality. The topic of the present study was to validate the applicability of the procedure in daily practice, giving physicians the ability to define areas for continuous quality improvement.

Methods

In ten endoscopy units in France, 200 patients per centre undergoing colonoscopy were enrolled in the study. An evaluation was carried out based on a prospectively developed checklist of 10 quality-control indicators including five dependent upon and five independent of the colonoscopy procedure.

Results

Of the 2000 procedures, 30% were done at general hospitals, 20% at university hospitals, and 50% in private practices. The colonoscopies were carried out for a valid indication for 95.9% (range 92.5–100). Colon preparation was insufficient in 3.7% (range 1–10.5). Colonoscopies were successful in 95.3% (range 81–99). Adenoma detection rate was 0.31 (range 0.17–0.45) in successful colonoscopies.

Conclusion

This tool for evaluating the quality of colonoscopy procedures in healthcare units is based on standard endoscopy and patient criteria. It is an easy and feasible procedure giving the ability to detect suboptimal practice and differences between endoscopy-units. It will enable individual units to assess the quality of their colonoscopy techniques.

[Abstinence from cocaine after long-term addiction]

BACKGROUND

Experimental data strongly suggest that in animal and probably in man, noradrenergic and serotoninergic become uncoupled during repeated consumption of drugs of abuse, strongly suggesting that different drugs share common mechanisms for drug-dependence. Using cocaine-dependence as model of strong addiction we speculate that careful analysis of psychic adjustments in patients who experience prolonged abstinence could be a useful tool for patient's care.

AIM

The aim of this retrospective study was first to establish similarities in patients' histories concerning modes of entrance, circumstances favouring the stopping, and modality of withdrawal. Secondly, we analysed the different ways used by subjects to substitute their cocaine-dependence.

PATIENTS AND METHODS

Cocaine-dependent subjects who had succeeded in supporting abstinence for at least 12 months without consumption were evaluated retrospectively by a face-to face interview.

RESULTS

We obtained a list of circumstances associated with entries and exit from cocaine-dependence. Second, when seeking for similarities in addictive behaviour, before and after, between cocaine users, we proposed to classify patients according to the strength in their addictive dominant trait between strong, moderate, mild, or absence of addictive behaviour. For didactic aims, purposes are illustrated by clinical vignettes.

CONCLUSIONS

This retrospective study allows us to clear arbitrarily four types of psychical modifications associated with prolonged abstinence in cocaine-dependent patients. Prospective clinical studies are clearly needed to standardize and to validate these clinical criteria.

Production of infectious hepatitis C virus in primary cultures of human adult hepatocytes

BACKGROUND & AIMS

Although hepatitis C virus (HCV) can be grown in the hepatocarcinoma-derived cell line Huh-7, a cell-culture model is needed that supports its complete, productive infection cycle in normal, quiescent, highly differentiated human hepatocytes. We sought to develop such a system.

METHODS

Primary cultures of human adult hepatocytes were inoculated with HCV derived from Huh-7 cell culture (HCVcc) and monitored for expression of hepatocyte differentiation markers and replication of HCV. Culture supernatants were assayed for HCV RNA, core antigen, and infectivity titer. The buoyant densities of input and progeny virus were compared in iodixanol gradients.

RESULTS

While retaining expression of differentiation markers, primary hepatocytes supported the complete infectious cycle of HCV, including production of significant titers of new infectious progeny virus, which was called primary-culture-derived virus (HCVpc). Compared with HCVcc, HCVpc had lower average buoyant density and higher specific infectivity; this was similar to the characteristics of virus particles associated with the very-low-density lipoproteins that are produced during in vivo infection. These properties were lost after re-culture of HCVpc in poorly differentiated Huh-7 cells, suggesting that authentic virions can be produced only by normal hepatocytes that secrete authentic very-low-density lipoproteins.

CONCLUSIONS

We have established a cell-culture-based system that allows production of infectious HCV in physiologically relevant human hepatocytes. This provides a useful tool for the study of HCV interactions with its natural host cell and for the development of antiviral therapies.

Inhibitory effects of cyclosporine on human regulatory T cells in vitro

BACKGROUND

Inevitable hepatitis C virus (HCV) recurrence after liver transplantation is a major barrier to the survival of a transplanted liver. It may be promoted by immunosuppression and the emergence of CD4+CD25+ regulatory T cells (Treg). Treg cells can mediate the induction and maintenance of immunological self-tolerance as well as transplant tolerance. We investigated the effects of cyclosporine (CsA), a widely used immunosuppressive agent, on human CD4+CD25+ Treg cells.

METHODS

Human CD4+CD25+ cells isolated from healthy donors were cultured in the presence of 40 or 400 ng/mL CsA. The suppressive activity of Treg was assessed in mixed leukocyte reactions (MLR) using CD25+ and autologous activated peripheral blood mononuclear cells (PBMC). Phenotype analysis (flow cytometric, Q-PCR) and cytokine production (ELISA) of Treg cells were then performed on cultures.

RESULTS

CsA (40 or 400 ng/mL) inhibited the proliferative capacity of PBMC and CD4+CD25+ Treg in a dose-dependent manner. Interestingly, addition of 40 ng/mL CsA in MLR impaired the suppressive activity of CD4+CD25+ cells, whereas a higher dose of CsA had no effect on Treg function. It appears that a therapeutic dose of CsA (40 ng/mL) did not change the phenotype of CD4+CD25+ T cells, but altered Treg activity by switching the regulatory to an inflammatory cytokine profile.

CONCLUSION

CsA significantly impaired the function of CD4+CD25+ Treg cells by inducing interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) secretion. The present studies suggested that CsA may block the induction of immune tolerance and decrease the risk of hepatitis C recurrence.

Increased expression of regulatory Tr1 cells in recurrent hepatitis C after liver transplantation

Immune response failure during HCV infection has been associated with the activity of regulatory T cells. Hepatitis C-related cirrhosis is the main reason for liver transplantation. However, 80% of transplanted patients present an accelerated recurrence of the disease. This study assessed the involvement of regulatory T-cell subsets (CD4+CD25+ cells: 'Treg' and CD49b+CD18+ cells: 'T regulatory-1' cells), in the recurrence of HCV after liver transplantation, using transcriptomic analysis, ELISA assays on serum samples and immunohistochemistry on liver biopsies from liver recipients 1 and 5 years after transplantation. Three groups of patients were included: stable HCV-negative recipients and those with mild and severe hepatitis C recurrence. At 5 years, Treg markers were overexpressed in all HCV+ recipients. By contrast, Tr1 markers were only overexpressed in patients with severe recurrence. At 1 year, a trend toward the overexpression of Tr1 was noted in patients evolving toward severe recurrence. IL-10 production, a characteristic of the Tr1 subset, was enhanced in severe recurrence at both 1 and 5 years. These results suggest that Tr1 are enhanced during severe HCV recurrence after liver transplantation and could be predictive of HCV recurrence. High levels of IL-10 at 1 year could be predictive of severe recurrence, and high IL-10 producers might warrant more intensive management.

Increased expression of regulatory Tr1 cells in recurrent hepatitis C after liver transplantation

Immune response failure during HCV infection has been associated with the activity of regulatory T cells. Hepatitis C-related cirrhosis is the main reason for liver transplantation. However, 80% of transplanted patients present an accelerated recurrence of the disease. This study assessed the involvement of regulatory T-cell subsets (CD4+CD25+ cells: 'Treg' and CD49b+CD18+ cells: 'T regulatory-1' cells), in the recurrence of HCV after liver transplantation, using transcriptomic analysis, ELISA assays on serum samples and immunohistochemistry on liver biopsies from liver recipients 1 and 5 years after transplantation. Three groups of patients were included: stable HCV-negative recipients and those with mild and severe hepatitis C recurrence. At 5 years, Treg markers were overexpressed in all HCV+ recipients. By contrast, Tr1 markers were only overexpressed in patients with severe recurrence. At 1 year, a trend toward the overexpression of Tr1 was noted in patients evolving toward severe recurrence. IL-10 production, a characteristic of the Tr1 subset, was enhanced in severe recurrence at both 1 and 5 years. These results suggest that Tr1 are enhanced during severe HCV recurrence after liver transplantation and could be predictive of HCV recurrence. High levels of IL-10 at 1 year could be predictive of severe recurrence, and high IL-10 producers might warrant more intensive management.

Analysis of gene transcription in sera during chronic hepatitis C infection

Alternative, non-invasive techniques are necessary to monitor the progression of liver disease during chronic hepatitis C. Firstly, because serum is the most accessible material for studies using qPCR in microplates, gene transcription was compared in 219 selected genes involved in the pathogenesis of hepatitis C virus (HCV) infection between sera, PBMCs and liver samples collected simultaneously from five patients infected chronically. Secondly, using sera, gene profiles were compared between HCV-infected patients (n = 10) and healthy controls (n = 10). In addition, the influence of alcohol intake was examined in patients infected with HCV genotype-1. Firstly, amplifiable mRNAs were obtained in all samples. After amplification, significant correlations were observed between: liver versus serum; liver versus PBMCs; and serum versus PBMCs (r(2) = 0.37, r(2) = 0.54, r(2) = 0.49, respectively). A comparison of gene transcription by gene involved in T- and B-cell markers, adhesion molecules, apoptosis, liver matrix turnover and inflammation, revealed comparable, significant correlations between serum and liver, (r(2) = 0.30, r(2) = 0.60, r(2) = 0.51, r(2) = 0.51, r(2) = 0.26, and r(2) = 0.61 respectively). Secondly, a quantitative analysis of gene expression in sera between genotype-1b-infected patients and healthy controls revealed that 41 genes involved closely in T-cell activation and apoptosis were over-expressed significantly in patients infected with HCV. In these patients, alcohol consumption was associated with an increased expression of six genes involved in the inflammatory response, together with a decrease of genes associated with dendritic cell function. It is concluded that in patients infected with HCV, serum can be used to evaluate expression of liver genes. Further prospective studies are clearly needed to validate the initial results and to define the relevant genes.

Interleukin-4 induces the activation and collagen production of cultured human intrahepatic fibroblasts via the STAT-6 pathway

Interleukin-4 (IL-4) is overexpressed in liver grafts in a context of severe recurrent hepatitis C, during which the development of fibrosis is dramatically accelerated. In this study, we examined the effects of IL-4 on the activation and collagen production of cultured human intrahepatic (myo)fibroblasts (hIHFs), and investigated the underlying mechanisms. The myofibroblastic nature of cells was evaluated morphologically using activation markers (smooth muscle alpha-actin, vimentin and prolyl 4-hydroxylase). Quiescent hIHFs were obtained by cell incubation in serum-free medium or cell culture on Matrigel. We first analyzed IL-4 receptor expression, STAT-6 activation by IL-4, and STAT-6 inhibition by an anti-IL-4 antibody or by STAT-6 small-interfering RNA (siRNA) transfection. We then focused on collagen production, using quantitative real-time PCR to analyze the effect of IL-4 on the mRNA expression of collagens I, III and IV, and on collagen levels in supernatants of hIHFs, using the Sircol collagen assay. hIHFs cultured in plastic wells appeared to be morphologically activated. The expression of activation markers was reduced by serum deprivation or culture on Matrigel, and restored by IL-4 incubation. The IL-4 receptor was expressed by hIHFs, and STAT-6 was activated following incubation with IL-4. Both anti-IL-4 antibody and STAT-6 siRNA transfection inhibited this activation. The treatment of hIHFs with IL-4 increased the mRNA expression of collagens I, III and IV (P<0.05) and elevated collagen levels in supernatants (P=0.01 vs untreated cells). Therefore, IL-4 exerts profibrotic effects by activating hIHFs and inducing collagen production and secretion. This effect requires IL4-R binding and STAT-6 activation. IL-4 may thus be involved in accelerated course of fibrogenesis during recurrent hepatitis C.

Rosiglitazone for nonalcoholic steatohepatitis: one-year results of the randomized placebo-controlled Fatty Liver Improvement with Rosiglitazone Therapy (FLIRT) Trial

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is a liver disease that complicates insulin-resistant states. This trial tested the efficacy and safety of rosiglitazone, an insulin-sensitizing agent, in patients with NASH.

METHODS

Sixty-three patients with histologically proven NASH were randomly assigned to receive rosiglitazone (4 mg/day for the first month and 8 mg/day thereafter; n = 32) or placebo (n = 31) for 1 year. Liver biopsy was performed at the end of treatment. End points were improvement in the histologic score of steatosis, normalization of serum transaminase levels, and improvement in necroinflammation and fibrosis.

RESULTS

More patients treated with rosiglitazone than receiving placebo had improved steatosis (47% vs 16%; P = .014) and normalized transaminase levels (38% vs 7%; P = .005), although only half of patients responded. There was no improvement in other histologic lesions, including fibrosis, and a composite score of activity, the nonalcoholic fatty liver disease activity score. Improvement of steatosis correlated with reduction of transaminase levels (r = 0.36; P < .005), improvement in insulin sensitivity (r = 0.34; P = .008), and increase in adiponectin levels (r = -0.54; P < .01) but not with weight variations. Independent predictors of response were rosiglitazone treatment, the absence of diabetes, and massive steatosis. Weight gain was the main adverse effect (mean gain of 1.5 kg in the rosiglitazone group vs -1 kg in the placebo group; P < .01), and painful swollen legs was the main reason for dose reduction/discontinuation. Serum hemoglobin level was slightly but significantly reduced. There was no hepatic toxicity.

CONCLUSIONS

In patients with NASH, rosiglitazone improves steatosis and transaminase levels despite weight gain, an effect related to an improvement in insulin sensitivity. However, there is no improvement in other parameters of liver injury.

CD25, CD28 and CD38 expression in peripheral blood lymphocytes as a tool to predict acute rejection after liver transplantation

BACKGROUND/AIM

The aim of this study was to determine whether the expression of CD25, CD28 and CD38 (which reflects the degree of T-cell activation) by peripheral blood mononuclear cells constitutes a useful means of measuring the immune status of liver transplant recipients.

METHODS

Fifty-two patients enrolled in a prospective randomized study comparing cyclosporine and tacrolimus as the principal immunosuppressive drugs were monitored prospectively. The expression of CD25, CD28 and CD38 was analyzed on CD3-, CD4- and CD8-positive cells from whole blood using flow cytometry. The prognostic value of baseline and day 14 measurements regarding acute rejection was examined using Kaplan-Meier estimates for univariate analyses and the Cox model for multivariate analyses.

RESULTS

The mean frequencies of CD28 and CD38-expressing T cells were significantly higher in patients with acute rejection (p = 0.01 and p = 0.001, respectively), whereas the frequency CD25-expressing T cells did not differ significantly. Under univariate analysis, baseline CD25 levels, the type of calcineurin inhibitor, as well as the CD28 and CD38 frequencies obtained at day 14 were associated with the subsequent development of acute rejection. Under multivariate analysis, only CD28 and CD38 frequencies obtained at day 14 were independently associated with acute rejection.

CONCLUSIONS

The evaluation of CD28 and CD38 expression in peripheral blood lymphocytes is a simple marker that could be used routinely in clinical practice to assess the level of immunosuppression.

Fulminant autoimmune hepatitis after successful interferon treatment in an HIV-HCV co-infected patient

Hepatitis C (HCV) treatment using interferon-alpha (IFN-alpha) and ribavirin is recommended in HIV/HCV co-infected patients to prevent liver cirrhosis and liver-related death. However, in addition to its antiviral activity, IFN is a pleiotropic cytokine able to synergistically amplify T-cell autoreactivity. Here, we report for the first time the induction of a subfulminant autoimmune hepatitis (AIH) after four months of a successful treatment of HCV-1b infection using peg-IFN and ribavirin, in a 48-year-old woman co-infected with HIV. Diagnosis was assessed according to the international AIH scoring system, including liver biopsy and confirmed by positive response to steroid challenge.

Elevated interleukin-4 expression in severe recurrent hepatitis C virus after liver transplantation

BACKGROUND

Chronic hepatitis C virus (HCV) is usually associated with high levels of hepatic interleukin (IL)-2 and low levels of IL-4 transcripts. HCV frequently recurs after liver transplantation, and its course is accelerated in this setting. We compared in situ expression of IL-2 and IL-4 in transplanted and nontransplanted patients with HCV.

METHODS

A total of 74 liver biopsy specimens were studied; 52 came from transplanted patients, 38 of whom were HCV-positive (17 mild and 21 severe cases of recurrent HCV) and 22 came from nontransplanted patients, 17 of whom were HCV-positive (7 mild and 10 severe cases of HCV). The expression of IL-2 and IL-4 mRNA and IL-4 protein was studied using the reverse transcriptase polymerase chain reaction and immunohistochemical methods, respectively.

RESULTS

IL-2 transcript levels were significantly higher in severe than in mild HCV in both liver graft recipients and nontransplanted patients. However, IL-2 levels were higher in nontransplanted than in transplanted patients. IL-4 transcripts and protein were preferentially detected in graft recipients with severe recurrent HCV.

CONCLUSION

IL-4 expression is elevated in severe recurrent HCV and may play a role in the progression of hepatic lesions after liver transplantation.

A novel, sensitive, and specific RT-PCR technique for quantitation of hepatitis C virus replication

The detection of negative-strand hepatitis C virus (HCV) RNA is a hallmark of replication. A highly sensitive and specific method is required to quantify the very low level of replication inherent to in vitro infection systems. Based on reverse transcription with a tagged primer in the 5' non-coding region of the HCV genome, followed by a nested PCR with a second round of real-time PCR, a novel method is described with improved sensitivity for negative-strand HCV RNA quantification. The lower detection level was 25 copies per reaction of negative-strand HCV RNA, even in the presence of 1 x 10(5) copies of positive-strand HCV RNA. This protocol was applied to the detection of negative HCV strand RNA in the liver of HCV-infected patients as well as in primary human hepatocytes infected in vitro. In both models, and particularly in each of three, independent in vitro infection experiments, this assay permitted the quantitation of HCV replication.

Interleukin-4 induces human hepatocyte apoptosis through a Fas-independent pathway

IL-4 is overexpressed in liver grafts during severe recurrent hepatitis C and rejection. Hepatocyte apoptosis is involved in both these phenomena. We therefore examined the proapoptotic effect of IL-4 on HepG2 cells and human hepatocytes in vitro, together with the underlying mechanisms. We first measured IL-4 receptor expression, STAT6 activation by IL-4, and STAT6 inhibition by an anti-IL-4 antibody or by STAT6 siRNA transfection. We then focused on the pathways involved in IL-4-mediated apoptosis and the role of STAT6 activation in apoptosis initiation. The IL-4 receptor was expressed on both cell types, and STAT6 was activated by IL-4. Both anti-IL-4 and STAT-6 siRNA inhibited this activation. IL-4 induced apoptosis of both HepG2 cells (P=0.008 vs. untreated control) and human hepatocytes (P<0.001 vs. untreated control). IL-4 reduced the mitochondrial membrane potential, activated Bid and Bax, and augmented caspase 3, 8, and 9 activity. STAT6 blockade inhibited IL-4-induced apoptosis. Expression of Fas and Fas ligand was unaffected when HepG2 cells and hepatocytes were cultured with IL-4, and Fas/FasL pathway blockade failed to inhibit IL-4-induced apoptosis. These results show that IL-4 induces apoptosis of human hepatocytes through IL-4 receptor binding, STAT6 activation, decreased mitochondrial membrane potential, and increased caspase activation, independently of the Fas pathway. IL-4 might thus contribute to the progression of severe liver graft damage.

Low density lipoprotein receptor transcripts correlates with liver hepatitis C virus RNA in patients with alcohol consumption

Alcohol consumption has a major impact on the natural history of chronic hepatitis C virus (HCV) infection, although the underlying mechanisms are still debated. We designed a clinical study to evaluate the impact of alcohol abuse on both viral load and expression of low-density lipoprotein receptor (LDLR) and CD81 expression. Thirty-eight consecutive HCV-infected patients were enrolled. Group 1 (n = 18), < or =10 g alcohol/day, group 2 (n = 8), < or =30 g alcohol/day, group 3 (n = 12), >or =30 g alcohol/day. Receptors expression was measured by flow cytometry analysis in peripheral blood mononuclear cells (PBMC) and by specific real-time retrotranscription polymerase chain reaction (RT-PCR) in the liver. Serum viral load was evaluated by quantification of both HCV genomic RNA and total core antigen. The hepatic viral load was assessed by real-time RT-PCR. Serum HCV-RNA and total core antigen were significantly correlated, and were higher, albeit not significantly, in group 3 than in group 1. Alcohol consumption had no effect on expression of HCV putative receptors in PBMC, except for CD81, which was upregulated on monocytes in group 2. In the liver, viral load and levels of LDLR transcripts were significantly higher in group 3 than in group 1. Remarkably, a significant positive correlation was found between LDLR transcripts and HCV-RNA (r2 = 0.83, P < 10(-3)). Finally, in vitro experiments suggested that the effect of ethanol on LDLR expression was indirectly mediated by both tumour necrosis factor-alpha and interleukin-1beta. In conclusion, this study is the first to support a role for LDLR in the natural infection by HCV in man.

[Management of psychological disorders in patients with chronic hepatitis C]

BACKGROUND

Chronic hepatitis C remains a public heath problem. In France, 400,000 to 500,000 subjects are chronically infected with HCV.

LITERATURE FINDINGS

The purpose of this review was first to summarize the clinical aspects of the disease and the guidelines and results of antiviral treatment. The authors focus on the psychiatric side effects of antiviral treatment, and discuss the importance of good patient-provider interaction in patient's satisfaction, highlighting the mandatory role of the dynamic management of patients by hepatologists and psychiastrists.

CONCLUSION

Multidisciplinary approaches have to be set up to better treat these patients.

Prise en charge des complications de la cirrhose chez les patients VIH co-infectés par une hépatite virale B ou C

Cirrhosis is a serious complication of viral hepatitis, and its incidence is increasing in HIV patients coinfected with HCV or HBV as they live longer, thanks to effective antiretroviral treatment (Haart). HIV coinfection accelerates the progression of fibrosis in hepatitis. To implement preventive measures, prompt diagnosis of cirrhosis is important, either by liver biopsy or the noninvasive tests for fibrosis now under wide study (FibroTest, FibroScan, etc.). Afterwards, assessment of the severity of cirrhosis and screening for complications are both necessary: testing for liver failure (Child-Pugh and MELD scores), portal hypertension (upper gastrointestinal endoscopy), and hepatocellular carcinoma (ultrasound and alpha fetoprotein assay). Careful consideration of drug prescriptions and possible interactions is essential. Specific treatment for hepatitis B or C virus is possible at this stage of cirrhosis, although more difficult, especially for HCV (results influenced by genotype, additional risk of complications by lactic acidosis or hepatic decompensation). Management of the complications of portal hypertension must be planned, as for those without HIV infection. Treatment of hepatocellular carcinoma is still disappointing, and liver transplantation, although possible in these patients, must be evaluated.

[Carcinomatous meningitis as a rare presentation of gastric cancer]

INTRODUCTION

Carcinomatous meningitis is a rare complication of gastric cancer.

CASE

A 46 year-old man with an unremarkable medical history was hospitalized for treatment of suspected meningitis. Despite treatment, his clinical state rapidly worsened and he died without regaining consciousness, shortly after transfer to the ICU. Autopsy showed that he had anchorage-independent cell gastric carcinoma, with simultaneous lymphatic, pulmonary, cutaneous and meningeal metastases.

DISCUSSION

The rising incidence of secondary meningeal lesions in the last two decades is probably associated with the treatment-related improvement in life expectancy. Prognosis is very grave, and median survival time is only several weeks. Carcinomatous meningitis is difficult to diagnosis, especially as the first sign of a primary tumor. This rare presentation of gastric cancer indicates diffuse metastatic spread and extremely poor prognosis.

Impaired expression of the peroxisome proliferator-activated receptor alpha during hepatitis C virus infection

BACKGROUND AND AIMS

Liver inflammation, fibrosis, and dyslipidemia are common features in patients with chronic hepatitis C virus (HCV) infection. Because peroxisome proliferator-activated receptor alpha (PPARalpha) is highly expressed in the liver and is involved in the regulation of lipid metabolism and inflammation, we sought to determine whether HCV infection may locally impair PPARalpha expression and activity.

METHODS

PPARalpha expression was investigated in liver biopsy specimens of 86 untreated patients with HCV infection and controls, by using real-time polymerase chain reaction (PCR), Western blot analysis, and immunohistochemistry. PPARalpha activity was assessed by quantification of the key gene target carnitine palmitoyl acyl-CoA transferase 1 (CPT1A) messenger RNA (mRNA). The influence of HCV core protein on PPARalpha mRNA expression was analyzed in vitro by real-time PCR in HCV core-expressing HepG2 cells activated with the PPARalpha ligand fenofibric acid.

RESULTS

Hepatic concentrations of PPARalpha and CPT1A expressed by hepatocytes were impaired profoundly in the livers of untreated patients with HCV infection compared with controls. A mean decrease of 85% in PPARalpha mRNA expression paralleled with a lack of CPT1A mRNA induction also were observed in HCV core-expressing HepG2 cells compared with controls.

CONCLUSIONS

HCV infection is related to altered expression and function of the anti-inflammatory nuclear receptor PPARalpha. These results identify hepatic PPARalpha as one mechanism underlying the pathogenesis of HCV infection, and as a new therapeutic target in traditional treatment of HCV-induced liver injury.

Response to antiviral treatment in hepatitis C virus-associated marginal zone lymphomas

A link between chronic hepatitis C virus (HCV) infection and low-grade B-cell lymphomas has been suggested by epidemiological studies. Marginal zone lymphomas (MZLs) including splenic lymphomas with villous lymphocytes are among the most frequently reported subgroups in the setting of chronic HCV infection. In this study, we examined the effect of antiviral treatment in eight patients with HCV-associated MZL. We found that five out of eight patients have responded to interferon alpha and ribavirin. In some cases, hematologic responses were correlated to virologic responses. In addition, we report a case of large granular lymphocyte leukemia occurring in association with MZL and HCV, and responding to interferon and ribavirin. We suggest that there is an etiologic link between HCV and antigen-driven lymphoproliferative disorders.

Hepatitis C virus NS5A-regulated gene expression and signaling revealed via microarray and comparative promoter analyses

Most individuals exposed to hepatitis C virus (HCV) become chronically infected and are predisposed to liver disease. The mechanisms underlying viral persistence and disease progression are unknown. A role for the HCV NS5A protein in viral replication and interferon resistance has been demonstrated. To identify mechanisms affected by NS5A, we analyzed the gene expression of Huh7 cells expressing NS5A and control cells using oligonucleotide microarrays. A set of 103 genes (43 up-regulated, 60 down-regulated) whose expression was modified by at least twofold was selected. These included genes involved in cell adhesion and motility, calcium homeostasis, lipid transport and metabolism, and genes regulating immune responses. The finding of modulated expression of genes related to the TGF-beta superfamily and liver fibrosis was observed. Interestingly, both the tumor necrosis factor and lymphotoxin beta receptors were down-regulated by NS5A. Similar data were obtained following expression of four NS5A mutants obtained from patients who were not responsive or were sensitive to interferon therapy. Through computational analysis, we determined that 39 of the 43 genes up-regulated by NS5A contained one or more nuclear factor kappaB (NF-kappaB) binding sites within their promoter region. Using the Gibbs sampling method, we also detected enrichment of NF-kappaB consensus binding sites in the upstream regions of the 43 coexpressed genes. Activation of NF-kappaB by NS5A was subsequently demonstrated in luciferase reporter assays. Adenovirus-mediated expression of IkappaBalpha reverted NS5A mediated up-regulation of gene expression. In conclusion, this study suggests a role of NS5A and NF-kappaB in HCV pathogenesis and related liver disease. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).

Defective inhibition of peripheral CD8+ T cell IL-2 production by anti-calcineurin drugs during acute liver allograft rejection

BACKGROUND

The aim of this study was to evaluate calcineurin activity and interleukin-2 (IL-2) expression by peripheral blood cells as a means of assessing the immune status of liver transplant recipients.

METHODS

Twenty-one patients were studied in a randomized study comparing cyclosporine and tacrolimus as the main immunosuppressive drug. Calcineurin activity was determined after separation of phosphorylated and dephosphorylated products of a calcineurin specific peptide substrate by high performance liquid chromatography(HPLC). Intracellular IL-2 expression was measured by flow cytometry. In 34 additional patients, intracellular IL-2 expression was prospectively measured.

RESULTS

Calcineurin activity fell after transplantation. Values were marginally higher in patients with acute rejection (P=0.059). The percentage of IL-2-producing T cells fell after transplantation. This percentage did not differ between patients with and without rejection. In contrast, the proportion of IL-2-producing CD8+ T cells was higher in patients with acute rejection than in patients free of acute rejection (P=0.003). Moreover, pretransplantation IL-2 expression by CD8+ T cells was higher in patients who subsequently developed acute rejection, suggesting that IL-2 production may be constitutively higher in those patients. The results obtained in the 34 additional patients confirmed these results.

CONCLUSIONS

These data suggest that quantification of intracellular IL-2 in CD8+ T cells may be a useful index of immune status in liver transplant recipients. Preoperative IL-2 levels might serve to individually tailor the immunosuppressive regimen.

[Cholestatic icterus induced by the administration of fusidic acid in a cirrhotic patient]

INTRODUCTION

Fucidic acid is an antibiotic essentially used to treat staphylococcal infections. Its chemical structure is very similar to that of bilary acids and hence implies competitive mechanisms between their elimination and metabolization.

OBSERVATION

A patient with a past history of alcohol-induced cirrhosis was treated with fucidic acid for a Staphylococci aureus urinary infection. On day 2 of treatment a conjugate bilirubine icterus appeared. There was no argument to suggest a decompensation of the icterus. The icterus disappeared on suspension of fucidic acid.

COMMENTS

The occurrence of an icterus in a cirrhotic patient may evoke decompensation of the hepatopathy and an extensive exploration must be made. A thorough survey of all drug administration must be made. Notably, the possibility of the occurrence of a connective bilirubin icterus during treatment with fucidic acid must be known. The icterus always regresses on withdrawal of treatment and this etiology must be evoked before conducting invasive examinations.

Effects of bile acids on the humoral immune response: a mechanistic approach

Whereas bile acids in excess depress the cell-mediated immune response, their effects on the humoral response have been little investigated. The aim of this study was to investigate the effects of bile acids on immunoglobulin production. Human peripheral blood mononuclear cells were stimulated for 5 days by Staphylococcus aureus Cowan I (SAC-I). Immunoglobulins were measured in the supernatants and cell lysates using ELISA. We found that bile acids inhibited IgM production in a dose-dependent manner. The inhibitory effects of 50 microM chenodeoxycholic acid (CDCA) and its glyco- and tauro-conjugates (62, 53 and 51%, respectively) were stronger than those of ursodeoxycholic acid (UDCA) and its conjugates (45, 40 and 34%, respectively). The inhibition of IgG production by CDCA and UDCA was weak (23 and 12%, respectively, at 50 microM). IgA production was not modified. The inhibition of intracellular IgM concentration paralleled that observed in the secreted compartment. By contrast, CDCA enhanced intracellular concentration of IgG. In the absence of significant necrosis or apoptosis, CDCA-mediated inhibition of SAC-I-induced IgM production was significantly correlated to the ability of the bile acid to inhibit cell proliferation (r=0.98; p<0.05). In conclusion, we showed that hydrophobic bile acids strongly depress the primary humoral response. This effect resulted from both an inhibition of cell proliferation, and to a lesser extent from a deficient exocytosis of immunoglobulins.

Activation of the interferon-inducible protein kinase PKR by hepatocellular carcinoma derived-hepatitis C virus core protein

Hepatitis C virus (HCV) is a major etiological agent of chronic liver disease and hepatocellular carcinoma (HCC). We demonstrate herewith that HCV core proteins encoded by sequences isolated from HCC tumor tissues, but not those derived from their non-tumor counterparts in the same liver, co-localise in vitro and in vivo and co-immunoprecipitate with PKR in hepatocytic Huh7 cells. We show that this association in fact augments the autophosphorylation of PKR and the phosphorylation of the translation initiation factor eIF2alpha, which are two markers of PKR activity. The present study therefore identifies a novel model of virus-cell interactions whereby a viral protein, the HCV core, activates PKR activity.

Expression of hepatitis C virus NS5A natural mutants in a hepatocytic cell line inhibits the antiviral effect of interferon in a PKR-independent manner

The impact of hepatitis C virus NS5A protein mutations on interferon alfa (IFN-alpha) signaling pathway, cell proliferation, and viability is an important issue that is still under debate. We have therefore combined transient and stable expression in a human hepatocytic cell line (Huh7) of 3 full-length NS5A sequences, isolated from patients with or without response to IFN-alpha therapy. Expression of all 3 NS5A-reduced IFN-alpha global antiviral activity on both vesicular stomatitis virus (VSV) and encephalomyocarditis virus (EMCV) replication. We did not show, however, an effect of these 3 NS5A proteins on double-stranded RNA-dependent kinase (PKR) expression and activity as well as colocalization and coimmunoprecipitation between NS5A and PKR. We also failed to show an effect of the 3 NS5A mutants tested on cell proliferation and viability. Overall, our results support an important role of NS5A in controlling IFN-alpha antiviral activity; they show, however, that PKR-independent mechanisms are implicated, at least in liver-derived cells.

[Liver transplantation for alcoholic liver disease]

Alcoholic cirrhosis is a major public health issue in France. The prevalence of alcoholic cirrhosis and the number of potential candidates for liver transplantation is unknown but certainly underestimated. Despite physicians' ethical reserves concerning this self-inflicted disease and the public's misgivings, liver transplantation for alcoholic cirrhosis can provide survival rates comparable with those observed for other chronic liver diseases. in this indication, liver transplantation if often associated with a low risk of acute rejection and a high rate cancer of the upper respiratory and digestive tracts. The risk of recurrent alcoholism after liver transplantation is also a major problem. Its prevalence varies from 10 to 50%, depending on the assessment criteria, and the rate recurrent risk for the liver graft (alcohol intake>40 g/d) is to the order of 10%. These figures illustrate the importance of careful management and support for these patients. At least 6 months weaning from alcohol is a commonly accepted selection criterion for transplantation candidates. Criteria for liver transplantation generally include patients aged under 65 years, weaned for more than 6 months, with Child C cirrhosis or less, uncontrollable digestive tract hemorrhage, spontaneous severe infection, hepatorenal syndrome, hepatopulmonary syndrome, or multifocal hepatocellular carcinoma if the largest nodule measures less than 3 cm. Acute alcoholic hepatitis is a severe disease, fatal in 50% of the cases, and resistant tot corticosteroid therapy. Liver transplantation in this subpopulation of often young patient who have not achieved weaning merits further evaluation.

Effects of bile salts and aliphatic ionic surfactants on human lymphocyte proliferation

BACKGROUND

The molecular mechanisms involved in the immunosuppressive properties of bile salts are partly unknown.

METHODS

The aim of the study was to compare the effects of bile salts to those of various compounds with a steroid structure, or straight-chain hydrocarbons of different lengths and polar groups in the human mixed lymphocyte reaction.

RESULTS

We showed a significant correlation between the effects of bile salts and a low critical micellar concentration, a high surface activity index, and the absence of conjugation. In addition to mixed lymphocyte reaction (MLR) inhibition, chenodeoxycholate (CDC) inhibit ConA-induced IL2 production without any effect on IL2 R expression. Fusidate, a negatively charged steroid, with physical properties comparable to those of deoxycholate, had similar effects. Cetyltrimethylammonium bromide (CTAB), which exhibited a very low critical micellar concentration, inhibited mixed lymphocyte reaction in an extent comparable to cyclosporin A. In contrast, aliphatic compounds with critical micellar concentrations in the same range as bile salts but with a lower molecular area had no effect.

CONCLUSIONS

Amphiphilic negatively charged molecules inhibit T-cell proliferation to an extent that is dependent upon their hydrophobicity. These results may be explained, at least in part, by a modification in the cell membrane lipid bilayer structure.

Bile acids modulate the interferon signalling pathway

We have previously shown that cholestasis and bile acids inhibit 2', 5' oligoadenylate synthetase (OAS) activity in the liver and in primary hepatocyte cultures. Here, we assessed the influence of bile acids on interferon (IFN) pathway activation in three hepatoma cell lines. In HepG2 cells, bile acids (100-200 micromol/L) inhibited IFN-induced 2',5' OAS activity to an extent depending on their surface activity index. In Western blot analysis, IFN-induced expression of two major antiviral proteins, MxA and OAS p100, was reduced by 54% +/- 8% and 44% +/- 12%, respectively, when cells were preincubated for 4 hours with 100 micromol/L chenodeoxycholic acid (CDCA). In the same conditions, CDCA did not modify the IFN-induced signal transducers and activators of transcription (STAT)s tyrosine phosphorylation. In contrast, it reduced IFN-induced MxA promoter activity by 60%. The inhibitory effect of CDCA was not mediated by a 4beta-phorbol 12beta-myristate 13alpha-acetate (PMA)-sensitive protein kinase C (PKC)-dependent pathway. Finally, using CHO cells stably expressing a functional human bile acid carrier (Na+-dependent taurocholate cotransporting polypeptide [NTCP]), we found that bile acid inhibition of the IFN pathway occurred in the range of more physiological concentrations (12-50 micromol/L). In summary, our results provide strong evidence that bile acids inhibit the induction of proteins involved in the antiviral activity of IFN. This might partly explain the lack of responsiveness to IFN therapy in some patients with advanced chronic viral liver diseases.

High doses of hydroxyethyl starch and human albumin have similar effects on monocyte function and oncotic pressure

The accumulation of hydroxyethyl starches (HES) in monocytes/macrophages has raised concern over their potential detrimental effects on host defences. We assessed prospectively the function of circulating monocytes isolated from patients treated with plasma exchange (PE) using HES. The study was carried out in the medical intensive care unit of a university hospital. Eight patients underwent PE for neurological disorders. Each patient underwent three PEs, 48 h apart. The total exchange volume was 4 L per PE. Only 4% human albumin was used for the first PE. In the second and third PEs, the plasma substitute was 2 L of HES (200,000/6%/0.62) and 2 L of albumin. Mononuclear cells were collected before and immediately after each PE and 48 h after the last PE. They were placed in suspension culture and incubated with lipopolysaccharide (LPS). Monocyte function was assessed in terms of procoagulant activity (PCA) and tumour necrosis factor alpha (TNF-alpha) production. LPS-stimulated PCA increased after the first PE (P < 0.05). Stimulated TNF-alpha production increased, but not significantly so. Similar effects were observed after the second and third PE (P < 0.05 for stimulated TNF-alpha). Values 48 h after the last PE were similar to those obtained before the second PE, suggesting that repeated infusions of HES had no detrimental effect on monocyte function. Furthermore, plasma oncotic pressure was preserved after PE with HES. These results support the partial replacement of costly human albumin with HES during repetitive PE, and suggest that HES might be a safe plasma expander in septic patients.

Evidence for a deficiency of interferon response in mononuclear cells from hepatitis C viremic patients

BACKGROUND/AIMS

The pathophysiology of chronic hepatitis C and the mechanisms of resistance to interferon alpha are poorly understood. The aim of this work was to assess the influence of HCV infection and the viral genotype on lymphocyte production of 2',5' oligo-adenylate synthetase activity and monocyte production of TNF alpha and IL1 beta.

METHODS

Mononuclear cells from 50 consecutive patients were studied after 6 months of interferon treatment. Patients with persistent viremia (PCR-positive, elevated ALT, n = 39) were compared with the PCR-negative patients with normal ALT activity (n = 11) of similar age and sex ratio.

RESULTS

Cells from the viremic patients showed lower basal and stimulated 2',5' oligo-adenylate synthetase activity, and a lower in vitro response capacity to human recombinant interferon. In contrast, no difference was observed in basal and stimulated TNF alpha or IL1 beta production between the two groups. In the PCR-positive patients the viral genotype had no significant influence on the response of mononuclear cells to interferon or endotoxin.

CONCLUSIONS

These results show that the presence of HCV in blood is associated with an elective defect in interferon system activation, independently of the viral genotype.

Bile acid inhibition of interferon activity in human lymphocytes: no evidence of oxidative stress

Cholestasis and bile acids are two factors involved in resistance to interferon therapy in patients with chronic hepatitis C. As bile acids inhibit the biological activity of this cytokine in vitro and are capable of generating oxidative stress in hepatocytes, we investigated the potential involvement of such a mechanism in human lymphocytes. Thus, we evaluated (a) the effects of bile acids (0-200 mumol L-1) on lymphocyte reduced glutathione content and malondialdehyde production and (b) the ability of antioxidants to prevent the inhibitory effect of chenodeoxycholic acid on interferon-induced lymphocyte 2',5'-oligoadenylate synthetase activity, an index of the biological activity of interferon. We found that treatment of lymphocytes with bile acids for 24 h did not induce malondialdehyde release or significantly modify cellular reduced glutathione content. Synthetic precursors of glutathione (N-acetylcysteine and S-adenosylmethionine) and antioxidants (superoxide dismutase and catalase) had no preventive influence on the inhibitory effect of chenodeoxycholic acid on interferon-induced 2',5'-oligoadenylate synthetase activity. These negative results do not provide evidence for the use of glutathione precursors in cholestatic conditions associated with viral diseases.

Effect of cholestasis and bile acids on interferon-induced 2',5'-adenylate synthetase and NK cell activities

BACKGROUND/AIMS

The mechanisms involved in resistance to interferon alfa in patients with chronic hepatitis C are unclear. Both cirrhosis and cholestasis have been shown to be predictive of resistance. The aim of this study was to evaluate the influence of cholestasis and bile acids on 2',5'-oligoadenylate synthetase and natural killer activities, which are both involved in the antiviral activity of interferon.

METHODS

2',5'-Oligoadenylate synthetase activity was evaluated in spleen, liver, and isolated hepatocytes from bile duct-ligated rats, and the effect of bile acids in vitro on interferon-induced 2',5'-oligoadenylate synthetase and natural killer activities was examined in fresh mononuclear cells from healthy subjects.

RESULTS

Cholestasis had a time-dependent inhibitory effect on 2',5'-oligoadenylate synthetase activity in liver, spleen, and isolated hepatocytes from cholestatic rats (-70%, 86%, and 70% relative to baseline, respectively). In vitro, endogenous bile acids had a concentration-dependent inhibitory effect on interferon-induced 2',5'-oligoadenylate synthetase and natural killer activities, which was related to their structure. This inhibitory effect correlated with the surface activity index.

CONCLUSIONS

Cholestasis and bile acids diminish the biological activity of interferon and natural killer activity. The results suggest a decrease in the antiviral defenses in cholestatic conditions.

Inhibition of procoagulant activity of human monocytes by chenodeoxycholic acid: involvement of protein kinase C

Endogenous bile acids such as chenodeoxycholic acid have been shown to display a suppressive effect in vitro on mononuclear cell activation. We investigated the signal transduction pathway involved in the effect of chenodeoxycholic acid on monocyte procoagulant activity, a model of monocyte activation. Chenodeoxycholic acid (25 to 250 mumol/L) had a concentration-dependent inhibitory effect on procoagulant activity expressed by endotoxin-stimulated mononuclear cells, with half-maximal and maximal inhibition occurring at concentrations of 100 and 250 mumol/L, respectively. The inhibitory effect of chenodeoxycholic acid was (a) closely mimicked by 4 beta-phorbol 12 beta-myristate 13 alpha-acetate (PMA), a protein kinase C activator, but not by forskolin or dibutyryl cyclic AMP, two activators of the protein kinase A-dependent pathway; (b) prevented by staurosporine, a potent protein kinase C inhibitor; (c) partially abolished in protein kinase C-depleted cells; and (d) observed in conditions under which chenodeoxycholic acid, like PMA, significantly increased (41%) protein kinase C activity, as assessed by phosphorylation of exogenous (histone III-S) and endogenous (37-kD protein) substrates. In conclusion, our results (a) provide clear evidence of a marked inhibitory effect of chenodeoxycholic acid on monocyte activation, suggesting a potential role of primary endogenous bile acids in the immune defect associated with cholestasis; and (b) indicate that the inhibition of monocyte activation by chenodeoxycholic acid is mediated by way of protein kinase C activation.

Differential effects of chenodeoxycholic and ursodeoxycholic acids on expression of procoagulant activity by human monocytes

Cell-mediated immunity is impaired during cholestasis, and there is evidence for the involvement of endogenous bile acids. The aim of this study was to evaluate the effects of individual bile acids on immunity and to determine whether monocytes are a target. The effects of bile acids on the procoagulant activity of human monocytes, a lymphocyte-dependent model of monocyte activation, were assessed. Chenodeoxycholic acid, one of the main human primary bile acids, had a concentration-dependent inhibitory effect on procoagulant activity expressed by endotoxin-stimulated mononuclear cells, with half-maximal and maximal inhibitions at 100 and 250 microM, respectively. The inhibitory concentrations were similar for the procoagulant activity of unstimulated mononuclear cells and for endotoxin-stimulated isolated monocytes. In contrast, ursodeoxycholic acid, a bile acid which has beneficial effects in cholestatic diseases, had no significant inhibitory effects at concentrations up to 250 microM. These results indicate that endogenous bile acids tend to inhibit monocyte activation, suggesting a potential role for primary endogenous bile acids in the immune defect associated with cholestasis; ursodeoxycholic acid, which is devoid of effects on the immune system, may potentially reverse cholestasis-induced immunodeficiency.

Current approach to the management of gastrinoma and insulinoma in adults with multiple endocrine neoplasia type I

The difficult and controversial diagnostic and therapeutic management of patients having gastrinoma or insulinoma with multiple endocrine neoplasia type I (MEN-I) has been discussed by reference to the literature and a personal series of 45 gastrinoma/MEN-I patients followed consecutively at Bichat Hospital. In both gastrinoma/ and insulinoma/MEN-I patients, anatomic distribution and morphology of tumoral process(es) are usually multiple, diffuse, of small size, and associated with endocrine cell hyperplasia and even nesidioblastosis. These features enhance the difficulty of tumor localization and eradication. Despite the dramatic development of modern medical imagery and surgical experience, the real possibility, on a long-term basis, of curing the patients from their disease remains limited, especially in the gastrinoma/MEN-I patients. In the latter group, according to our experience, persistence or recurrence of the disease after surgery is usual, and metachronous hepatic metastasis development is frequently observed when the follow-up is long enough. Patients with liver metastases, however, seem to undergo a more indolent course than sporadic gastrinoma cases. In insulinoma/MEN-I patients, removal of the functionally dominant islet cell area(s) is essential. Various preoperative and intraoperative localization techniques allow efficacious selective pancreatic surgery in many cases. The latter refinements and the promises of long-acting somatostatin analogs, if confirmed, might restrict to exceptional circumstances the indication of near-total or total pancreatectomy.

Clinical, anatomical, and evolutive features of patients with the Zollinger-Ellison syndrome combined with type I multiple endocrine neoplasia

The clinical evolution of type I multiple endocrine neoplasia (MEN I) was studied in 45 patients among a consecutive series of 172 with Zollinger-Ellison syndrome (ZES). These 172 patients were seen in our hospital between 1959 and 1989. Diarrhea was half as frequent in ZES-MEN I as in sporadic ZES cases. At diagnosis, mean basal acid output and serum gastrin levels in MEN I patients (28.8 +/- 6.6 mmol/h and 587 +/- 487 pg/ml, respectively) were not different from those observed in the others with sporadic ZES. Laparotomy was performed in all 36 patients with no diffuse liver involvement to attempt the removal of gastrinomas. Twenty-nine patients had adenomas, located in the pancreas in 21, in the duodenal wall in 3, and in both in 5. Adenomas were multiple in 23 cases (78%). No tumor was found in seven patients. Twenty-nine of the 36 operated patients were tumor-free after surgery; 7 died in the postoperative period between 1959 and 1970. Median follow-up of the 38 other patients was 95 months (range 17-278 months). Among the 24 patients without residual tumor at discharge (group I), biological and/or morphological evidence of a persistent or recurrent source of gastrin was obtained in 22. Among the 14 patients with residual tumor (group II), an increase in tumor size was seen in 5 after a median of 27 months (range 9-36 months), while no change occurred in 9 after 54 months (3-100 months). Actuarial survival curves were not different, either in group I versus group II patients (67 and 72% at 5-year follow-up, respectively) or in MEN I versus sporadic ZES patients. Apparently, complete resection of primary tumor did not reduce the incidence of subsequent liver metastases. In all, 21 of the 45 patients had malignant gastrinomas (47%), consisting of liver metastases in 14 (31%), metastatic lymph nodes in 11 (24%), and lung metastases in 2 (4%). Monitoring of fundic argyrophil cells disclosed hyperplasia in 13 of the 14 MEN I patients (92%), and 5 had invasive carcinoid tumors. Taken together, these results prompt us to recommend that in ZES-MEN I patients, surgery should be avoided and oxyntic mucosa regularly monitored.