Heart-type fatty acid binding protein is associated with proteinuria in obesity

PLoS One. 2012;7(9):e45691. doi: 10.1371/journal.pone.0045691. Epub 2012 Sep 18.

Abstract

Rationale: Lipid metabolism contributes to the formation of obesity-related glomerulopathy (ORG). Heart-type fatty acid binding protein (H-FABP or FABP3) is involved in lipid metabolism and was predicted to relate to renal lesions in obesity.

Methods: A total of 28 patients with ORG were investigated, and renal tissue from 7 kidney donors served as controls. Db/db mice with albuminuria were treated with Simvastatin for 12 weeks.

Results: Immunohistochemistry demonstrated the H-FABP staining in glomerular and tubular areas of patients with ORG, and the percentage of H-FABP in the glomerular area was significantly higher than in controls (15.8±1.62 versus 4.51±0.56%, P<0.001). Moreover, H-FABP expression correlated with proteinuria, high-density lipoprotein (HDL) cholesterol, waist circumference and the homeostatic model assessment - insulin resistance (HOMA-IR) among patients with ORG. Enhanced expression of H-FABP was also detected in the db/db mice, and expression increased from 8 to 20 weeks of age and was weakly related to increased albuminuria (r = 0.433; P = 0.020). Furthermore, H-FABP was co-localized with synaptopodin and demonstrated a podocyte pattern distribution. After Simvastation treatment, the urine albumin levels decreased with lipid levels and H-FABP expression in the glomeruli. The expression of H-FABP was related to Simvastatin treatment, albuminuria and triglycerides, while it was only linked with triglycerides and albuminuria (r = 0.643, P = 0.036).

Conclusions: This study confirmed an association of H-FABP with the pathogenesis of clinical and experimental ORG, and suggests that such a process might be related to podocytes and lipid dysmetabolism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Fatty Acid Binding Protein 3
  • Fatty Acid-Binding Proteins / metabolism*
  • Humans
  • Immunohistochemistry
  • Mice
  • Mice, Inbred C57BL
  • Obesity / complications
  • Obesity / metabolism*
  • Podocytes / metabolism
  • Proteinuria / complications
  • Proteinuria / metabolism*

Substances

  • FABP3 protein, human
  • Fatty Acid Binding Protein 3
  • Fatty Acid-Binding Proteins

Grant support

This work was supported by the National Natural Science Foundation of China (grant number: 30800546, 81070579) and the Doctoral Foundation of Education Ministry of China (grant number: 200802841008). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.