Retinol-binding protein 4: a promising circulating marker of liver damage in pediatric nonalcoholic fatty liver disease.

Abstract

BACKGROUND & AIMS:

Noninvasive methods are needed to identify pediatric nonalcoholic fatty liver disease (NAFLD), the most frequent chronic liver disease in children and adolescents in industrialized countries. Retinol-binding protein 4 (RBP4) is an adipocytokine that has been associated with the pathogenesis of insulin resistance. We tested the serum levels of RBP4 to assess their associations with the metabolic profile and histologic features in a large well-characterized group of children with NAFLD.

METHODS:

The study included 59 children with biopsy-proven NAFLD. Histologic analyses were performed by an experienced hepatopathologist; the NAFLD activity score and fibrosis score were calculated for each patient. RBP4 levels in serum samples were measured by an enzyme-linked immunosorbent assay analysis. Anthropometric, blood pressure, and metabolic profile analyses (including glucose tolerance, fasting glucose, insulin, and lipid panel tests) were performed on samples from all patients.

RESULTS:

Decreasing levels of RBP4 were associated significantly with increasing levels of serum triglyceride. High levels of RBP4 were associated significantly with low necroinflammatory activity, a low NAFLD activity score, and a low fibrosis score. Furthermore, serum RBP4 levels decreased significantly as disease severity increased; there was a stepwise decrease in RBP4 from children with steatosis (3.8 mg/dL) to borderline nonalcoholic steatohepatitis (2.9 mg/dL) to definitive nonalcoholic steatohepatitis (1.9 mg/dL) (P < .0001). This association remained significant after adjusting for other relevant clinical variables.

CONCLUSIONS:

Our study shows an inverse relationship between RBP4 levels and degree of liver damage. RBP4 therefore might be a potential novel noninvasive marker of severity of pediatric NAFLD.

• Authors: Valerio Nobili, Naim Alkhouri, Anna Alisi, Simonetta Ottino, Rocio Lopez, Melania Manco, Ariel E Feldstein
• Journal: Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association (Clin Gastroenterol Hepatol) Vol. 7 Issue 5 Pg. 575-9 (May 2009) ISSN: 1542-7714 [Electronic] United States
• PMID: 19268270 (Publication Type: Journal Article)

Chemical References

• Biomarkers
• RBP4 protein, human
• Retinol-Binding Proteins, Plasma

Topics

• Adolescent
• Biomarkers (analysis)
• Biopsy
• Child
• Fatty Liver (diagnosis)
• Female
• Humans
• Liver (pathology, physiopathology)
• Liver Cirrhosis (pathology)
• Male
• Metabolome
• Retinol-Binding Proteins, Plasma (analysis)
• Serum (chemistry)
• Severity of Illness Index