Regenerating islet-derived protein 3α: A promising therapy for diabetes. Preliminary data in rodents and in humans.

The aim of our study was to test the hypothesis that administration of Regenerating islet-derived protein 3α (Reg3α), a protein described as having protective effects against oxidative stress and anti-inflammatory activity, could participate in the control of glucose homeostasis and potentially be a new target of interest in the treatment of type 2 diabetes. To that end the recombinant human Reg3α protein was administered for one month in insulin-resistant mice fed high fat diet. We performed glucose and insulin tolerance tests, assayed circulating chemokines in plasma and measured glucose uptake in insulin sensitive tissues. We evidenced an increase in insulin sensitivity during an oral glucose tolerance test in ALF-5755 treated mice vs controls and decreased the pro-inflammatory cytokine C-X-C Motif Chemokine Ligand 5 (CXCL5). We also demonstrated an increase in glucose uptake in skeletal muscle. Finally, correlation studies using human and mouse muscle biopsies showed negative correlation between intramuscular Reg3α mRNA expression (or its murine isoform Reg3γ) and insulin resistance. Thus, we have established the proof of concept that Reg3α could be a novel molecule of interest in the treatment of T2D by increasing insulin sensitivity via a skeletal muscle effect.

A Proof of Concept, Phase II Randomized European Trial, on the Efficacy of ALF-5755, a Novel Extracellular Matrix-Targeted Antioxidant in Patients with Acute Liver Diseases.

OBJECTIVE: No efficient medical treatment is available for severe acute hepatitis (SAH) except N-acetylcysteine for acetaminophen-induced acute liver failure. The human C-type lectin Reg3α, referred to as ALF-5755, improved survival in an animal model of acute liver failure and was well tolerated in a phase 1 trial in humans. We performed a phase 2a trial of ALF5755 in non-acetaminophen induced SAH. DESIGN: double-blind, randomized, placebo-controlled study. The primary end-point was the improvement in the coagulation protein synthesis assessed by the change of Prothrombin (PR) during the 72 hours following treatment initiation calculated as PRH0 minus PRH72 divided by 72 (PR slope H0H72). Intention to treat (ITT) and per-protocol (PP) analysis of the entire group and the Hepatitis B virus (HBV)/AIH (auto-immune hepatitis) sub-group were done separately. RESULTS: 57 patients were included. Twenty-eight received ALF-5755, 29 the placebo. Etiologies were: Hepatitis A (n = 10), HBV (n = 13), AIH (n = 9), drug-induced (n = 8), other (n = 17). On the whole group, nor the PR slope H0H72 (0.18±0.31 vs 0.25±0.32), nor the transplant-free survival rate at day 21 (75 vs 86%) differed between groups. Conversely, in the HBV-AIH subgroup, in which ALF was more severe, PR slope H0-H72 was higher in the ALF-5755 arm, the difference being significant in PP analysis (0.048±0.066 vs -0.040±0.099, p = 0.04); the median length of hospitalization was lower in the ALF-5755 group (8 vs 14 days, p = 0.02). CONCLUSION: ALF-5755 was not efficient in a ITT analysis performed on the whole sample; however it led to a significant, although moderate, clinical benefit in a PP analysis of the sub-group of patients with HBV or AIH related SAH. As HBV is the major cause of SAH in Asia and Africa and AIH a growing cause, this study emphasizes the need to pursuit the evaluation of this novel medical treatment of SAH. TRIAL REGISTRATION: ClinicalTrials.gov NCT01318525.

Actual incidence and long-term consequences of posthepatectomy liver failure after hepatectomy for colorectal liver metastases.

INTRODUCTION: Posthepatectomy liver failure (PHLF) is a severe complication after hepatectomy for colorectal liver metastases. This study evaluated its actual incidence and its effects on short- and long-term overall survival (OS) in a specialized center. MATERIALS AND METHODS: Between 2006 and 2008, 193 patients who underwent 232 hepatectomies (147 minor and 85 major) for colorectal liver metastasis were studied prospectively. Hepatectomy was performed if the remnant liver volume was >0.5% of body weight. Uni- and multivariate analyses on OS after all hepatectomies (n = 232) or major resection only (n = 85) were then performed on pre-, intra-, and postoperative (including pathological) data to determine the consequences of PHLF by comparison with those of other intra- and postoperative events. RESULTS: The 3-month postoperative mortality rate was 0.8%. PHLF was observed in six patients (7%) after major hepatectomy and in one (0.6%) after minor hepatectomy. With a 25-month follow-up, the 2-year OS rate was 84%. Preoperatively, pulmonary metastasis was the only determinant of OS. Intra- and postoperatively, four factors were determinant of OS: PHLF (risk ratio [RR] = 3.84, P = .04), mental confusion (RR = 3.11, P = .006), fluid collection (RR = 2.9, P = .01) and transfusion (RR = 2.27, P = .009). After major hepatectomy, only PHLF (RR = 4.14, P = .01) and confusion (RR = 3.6, P = .02) were identified. CONCLUSION: With improvements in postoperative management, PHLF was found to be less responsible for 3-month mortality but remains an event that exerts a major impact on 2-year survival.

Human hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein cures fas-induced acute liver failure in mice by attenuating free-radical damage in injured livers.

UNLABELLED: Acute liver failure (ALF) is a rare syndrome with a difficult clinical management and a high mortality rate. During ALF, several molecular pathways governing oxidative stress and apoptosis are activated to induce massive tissue injury and suppress cell proliferation. There are few anti-ALF drug candidates, among which is the C-type lectin Reg3α, or human hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein (HIP/PAP), which displayed promising properties for tissue regeneration and protection against cellular stress in transgenic mice. We report on substantial preclinical and clinical advances in the development of a recombinant (rc) full-length human HIP/PAP protein as an anti-ALF drug. The curative effects and mechanisms of action of rcHIP/PAP were investigated in murine Fas-induced ALF. Primary hepatocytes were cultured with cytotoxic doses of tumor necrosis factor α/actinomycin-D, transforming growth factor ß, agonistic Fas antibody or hydrogen peroxide, and various concentrations of rcHIP/PAP. Cell viability, proliferation index, apoptosis, and oxidation were monitored. We found that rcHIP/PAP significantly improved survival in Fas-intoxicated mice in a dose-dependent and time-dependent manner, with optimum effects when it was injected at advanced stages of ALF. Primary hepatocytes were efficiently protected against multiple cell death signals by rcHIP/PAP. This survival benefit was linked to a depletion of oxidized biomolecules in injured liver cells due to a strong reactive oxygen species scavenging activity of rcHIP/PAP. Clinically, an escalating dose phase 1 trial demonstrated a good tolerability and pharmacokinetic profile of rcHIP/PAP in healthy subjects. CONCLUSION: The rcHIP/PAP protein exhibited significant curative properties against ALF in mice. It is a free-radical scavenger that targets a broad spectrum of death effectors and favors liver regeneration. The good safety profile of rcHIP/PAP during a phase 1 trial encourages evaluation of its efficacy in patients with ALF.

Dysfunction of the cholesterol biosynthetic pathway in Huntington's disease.

The expansion of a polyglutamine tract in the ubiquitously expressed huntingtin protein causes Huntington's disease (HD), a dominantly inherited neurodegenerative disease. We show that the activity of the cholesterol biosynthetic pathway is altered in HD. In particular, the transcription of key genes of the cholesterol biosynthetic pathway is severely affected in vivo in brain tissue from HD mice and in human postmortem striatal and cortical tissue; this molecular dysfunction is biologically relevant because cholesterol biosynthesis is reduced in cultured human HD cells, and total cholesterol mass is significantly decreased in the CNS of HD mice and in brain-derived ST14A cells in which the expression of mutant huntingtin has been turned on. The transcription of the genes of the cholesterol biosynthetic pathway is regulated via the activity of sterol regulatory element-binding proteins (SREBPs), and we found an approximately 50% reduction in the amount of the active nuclear form of SREBP in HD cells and mouse brain tissue. As a consequence, mutant huntingtin reduces the transactivation of an SRE-luciferase construct even under conditions of SREBP overexpression or in the presence of an exogenous N-terminal active form of SREBP. Finally, the addition of exogenous cholesterol to striatal neurons expressing mutant huntingtin prevents their death in a dose-dependent manner. We conclude that the cholesterol biosynthetic pathway is impaired in HD cells, mice, and human subjects, and that the search for HD therapies should also consider cholesterol levels as both a potential target and disease biomarker.

Prenatal exposure to alcohol does not affect radial maze learning and hippocampal mossy fiber sizes in three inbred strains of mouse.

BACKGROUND: The aim of this study was to investigate the effects of prenatal alcohol exposure on radial-maze learning and hippocampal neuroanatomy, particularly the sizes of the intra- and infrapyramidal mossy fiber (IIPMF) terminal fields, in three inbred strains of mice (C57BL/6J, BALB/cJ, and DBA/2J). RESULTS: Although we anticipated a modification of both learning and IIPMF sizes, no such effects were detected. Prenatal alcohol exposure did, however, interfere with reproduction in C57BL/6J animals and decrease body and brain weight (in interaction with the genotype) at adult age. CONCLUSION: Prenatal alcohol exposure influenced neither radial maze performance nor the sizes of the IIPMF terminal fields. We believe that future research should be pointed either at different targets when using mouse models for Fetal Alcohol Syndrome (e.g. more complicated behavioral paradigms, different hippocampal substructures, or other brain structures) or involve different animal models.

Increased drinking in mutant mice with truncated M5 muscarinic receptor genes.

The rarest and least understood of the muscarinic receptors is the M5 subtype. Recombinant methods were used to create mutant mice with a deletion in the third intracellular loop of the M5 receptor gene. Salivation induced by the nonselective muscarinic agonist pilocarpine (1 mg/kg s.c.) was reduced in homozygous mutants from 15 to 60 min after injection as compared with wild-type mice. After 18-h food and water deprivation, drinking was increased in homozygous mutants, but feeding was not increased. The mutant and wild-type mice had similar responses in tests of open-field exploration, seizures induced by pilocarpine (300 mg/kg) or hypothermia induced by pilocarpine (1-3 mg/kg). These results indicate that M5 muscarinic receptors are important for fluid intake and suggest that M5 receptors are involved in slow secretory processes.