D. Oró

Cerium oxide nanoparticles reduce steatosis, portal hypertension and display anti-inflammatory properties in rats with liver fibrosis

BACKGROUND & AIMS Cerium oxide nanoparticles (CeO2NPs) have proven to behave as free radical scavengers and/or anti-inflammatory agents. The aim of the study was to determine whether CeO2NPs display hepatoprotective properties in experimental chronic liver disease. METHODS Systemic and hepatic effects of nanoparticles were assessed in CCl4-treated rats receiving CeO2NPs or vehicle twice weekly for two weeks and CCl4 treatment was continued for 8 additional weeks. Thereafter, mean arterial pressure and portal pressure (PP) were assessed and serum samples obtained to measure standard hepatic and renal function tests. Organ and subcellular distribution of NPs were assessed using mass spectrometry (ICP-MS) and transmission electron microscopy. Liver samples were obtained to evaluate steatosis, α-SMA expression, macrophage infiltration, apoptosis and mRNA expression of oxidative stress, inflammatory or vasoactive related genes. RESULTS Most CeO2NPs were located in the liver and it reduced hepatic steatosis, ameliorated systemic inflammatory biomarkers and improved PP without affecting mean arterial pressure. In addition, a marked reduction in mRNA expression of inflammatory cytokines (TNFα, IL1β, COX-2, iNOS), ET-1 and messengers related to oxidative (Epx, Ncf1, Ncf2) or endoplasmic reticulum (Atf3, Hspa5) stress signaling pathways was observed in the liver of rats receiving CeO2NPs. This was associated with reduced macrophage infiltration and reduced abundance of caspase-3, α-SMA and inflammatory cytokines. CONCLUSIONS CeO2NPs administration to CCl4-treated rats protects against chronic liver injury by reducing liver steatosis and portal hypertension and markedly attenuating the intensity of the inflammatory response, thereby suggesting that CeO2NPs may be of therapeutic value in chronic liver disease.

Adenoviral dominant-negative soluble PDGFRβ improves hepatic collagen, systemic hemodynamics, and portal pressure in fibrotic rats

BACKGROUND & AIMS Platelet-derived growth factor (PDGF) is the most potent stimulus for proliferation and migration of stellate cells. PDGF receptor β (PDGFRβ) expression is an important phenotypic change in myofibroblastic cells that mediates proliferation and chemotaxis. Here we analyzed the relationship between PDGFRβ expression, hemodynamic deterioration, and fibrosis in CCl(4)-treated rats. Thereafter, we investigated the effects produced by an adenovirus encoding a dominant-negative soluble PDGFRβ (sPDGFRβ) on hemodynamic parameters, PDGFRβ signaling pathway, and fibrosis. METHODS Mean arterial pressure, portal pressure, PDGFRβ mRNA expression, and hepatic collagen were assessed in 6 controls and 21 rats induced to hepatic fibrosis/cirrhosis. Next, 30 fibrotic rats were randomized into three groups receiving iv saline and an adenovirus encoding for sPDGFRβ or β-galactosidase. After 7days, mean arterial pressure, portal pressure, serum sPDGFRβ, and hepatic collagen were measured. RESULTS CCl(4)-treated animals for 18weeks showed a significantly higher increase in PDGFRβ mRNA compared to those treated for 13weeks and control rats. In CCl(4)-treated rats, the fibrous tissue area ranged from moderate to severe fibrosis. A direct relationship between the degree of fibrosis, hemodynamic changes, and PDGFRβ expression was observed. Fibrotic rats transduced with the adenovirus encoding sPDGFRβ showed increased mean arterial pressure, decreased portal pressure, lower activation of the PDGFRβ signaling pathway, and reduced hepatic collagen than fibrotic rats receiving β-galactosidase or saline. CONCLUSIONS PDGFRβ activation closely correlates with hemodynamic disorders and increased fibrosis in CCl(4)-treated rats. Adenoviral dominant negative soluble PDGFRβ improved fibrosis. As a result, the hemodynamic abnormalities were ameliorated.

Vasopressin 1a receptor partial agonism increases sodium excretion and reduces portal hypertension and ascites in cirrhotic rats

Patients and rats with cirrhosis and ascites have portal hypertension and circulatory dysfunction. Synthetic arginine vasopressin (AVP) receptor agonists able to induce systemic and mesenteric vasoconstriction have shown their usefulness in reducing portal pressure (PP) in this condition. We assessed the potential therapeutic value of a new V1a‐AVP receptor partial agonist with a preferential splanchnic vasoconstrictor effect (FE 204038) in rats with cirrhosis and ascites. The hemodynamic effects of cumulative intravenous doses of FE 204038, terlipressin, or vehicle were investigated. Mean arterial pressure and PP were continuously recorded and cardiac output and systemic vascular resistance (SVR) assessed at 30‐minute intervals for 90 minutes. Urine volume, urine osmolality, and urinary excretion of sodium and creatinine were measured in basal conditions and following twice‐daily subcutaneous doses of FE 204038 or vehicle. PP, mean arterial pressure, cardiac output, SVR, and ascites volume were also measured after 6 days. The expression of an array of vasoactive genes was assessed in the thoracic aorta and the mesenteric circulation of control rats and rats with cirrhosis and ascites. FE 204038 dose‐dependently decreased PP, did not modify mean arterial pressure, and increased SVR. The effect of the V1a‐AVP receptor partial agonist on PP was associated with an improvement in urine volume and urinary excretion of sodium during the first day of treatment. SVR was higher and cardiac output and ascites volume were lower in rats with cirrhosis and ascites treated with FE 204038. V1a‐AVP receptor expression in rats with cirrhosis and ascites was markedly enhanced in the mesenteric circulation compared to the thoracic aorta. Conclusion: FE 204038 increases sodium excretion and reduces portal hypertension and ascites in experimental cirrhosis. V1a‐AVP receptor partial agonism could be a useful pharmacological treatment in decompensated patients with cirrhosis. (Hepatology 2016;63:207–216)

Apo AIV and Citrulline Plasma Concentrations in Short Bowel Syndrome Patients: The Influence of Short Bowel Anatomy

Introduction Parenteral nutrition (PN) dependence in short bowel syndrome (SBS) patients is linked to the functionality of the remnant small bowel (RSB). Patients may wean off PN following a period of intestinal adaptation that restores this functionality. Currently, plasma citrulline is the standard biomarker for monitoring intestinal functionality and adaptation. However, available studies reveal that the relationship the biomarker with the length and function of the RSB is arguable. Thus, having additional biomarkers would improve pointing out PN weaning. Aim By measuring concomitant changes in citrulline and the novel biomarker apolipoprotein AIV (Apo AIV), as well as taking into account the anatomy of the RSB, this exploratory study aims to a better understanding of the intestinal adaptation process and characterization of the SBS patients under PN. Methods Thirty four adult SBS patients were selected and assigned to adapted (aSBS) and non-adapted (nSBS) groups after reconstructive surgeries. Remaining jejunum and ileum lengths were recorded. The aSBS patients were either on an oral diet (ORAL group), those with intestinal insufficiency, or on oral and home parenteral nutrition (HPN group), those with chronic intestinal failure. Apo AIV and citrulline were analyzed in plasma samples after overnight fasting. An exploratory ROC analysis using citrulline as gold standard was performed. Results Biomarkers, Apo AIV and citrulline showed a significant correlation with RSBL in aSBS patients. In jejuno-ileocolic patients, only Apo AIV correlated with RSBL (rb = 0.54) and with ileum length (rb = 0.84). In patients without ileum neither biomarker showed any correlation with RSBL. ROC analysis indicated the Apo AIV cut-off value to be 4.6 mg /100 mL for differentiating between the aSBS HPN and ORAL groups. Conclusions Therefore, in addition to citrulline, Apo AIV can be set as a biomarker to monitor intestinal adaptation in SBS patients. As short bowel anatomy is shown to influence citrulline and Apo AIV plasma values, both biomarkers complement each other furnishing a new insight to manage PN dependence.

Sipa1l1 is an early biomarker of liver fibrosis in CCl4-treated rats

ABSTRACT At present, several procedures are used for staging liver fibrosis. However, these methods may involve clinical complications and/or present diagnostic uncertainty mainly in the early stages of the disease. Thus, this study was designed to unveil new non-invasive biomarkers of liver fibrosis in an in vivo model of fibrosis/cirrhosis induction by CCl4 inhalation by using a label-free quantitative LC-MS/MS approach. We analyzed 94 serum samples from adult Wistar rats with different degrees of liver fibrosis and 36 control rats. Firstly, serum samples from 18 CCl4-treated rats were clustered into three different groups according to the severity of hepatic and the serum proteome was characterized by label-free LC-MS/MS. Furthermore, three different pooled serum samples obtained from 16 control Wistar rats were also analyzed. Based on the proteomic data obtained, we performed a multivariate analysis which displayed three main cell signaling pathways altered in fibrosis. In cirrhosis, more biological imbalances were detected as well as multi-organ alterations. In addition, hemopexin and signal-induced proliferation-associated 1 like 1 (SIPA1L1) were selected as potential serum markers of liver fibrogenesis among all the analyzed proteins. The results were validated by ELISA in an independent group of 76 fibrotic/cirrhotic rats and 20 controls which confirmed SIPA1L1 as a potential non-invasive biomarker of liver fibrosis. In particular, SIPA1L1 showed a clear diminution in serum samples from fibrotic/cirrhotic rats and a great accuracy at identifying early fibrotic stages. In conclusion, the proteomic analysis of serum samples from CCl4-treated rats has enabled the identification of SIPA1L1 as a non-invasive marker of early liver fibrosis. Summary: Proteomic analysis of serum samples from fibrotic and cirrhotic rats revealed a reduction in SIPA1L1 concentration with potential use as a marker for early liver fibrosis diagnosis.

P33 HEPATOPROTECTIVE EFFECT OF CeO2 NANOPARTICLES IN RATS TREATED WITH CCl4

Resumen del poster presentado al International Liver Congress-49th Annual Meeting of the European Association for the Study of the Liver, celebrado del 9 al 13 de Abril de 2014 en London (UK).-- et al.