title: Urinary fatty acid-binding protein as a new clinical marker of the progression of chronic renal disease.
abstract: Previous studies have indicated that in massive proteinuria, free fatty acids (FFAs) bound to albumin were overloaded in the proximal tubule and exacerbated tubulointerstitial damage. Liver-type fatty acid-binding protein (L-FABP) is an intracellular carrier protein of FFAs that is expressed in the proximal tubule of human kidney. We sought to evaluate urinary L-FABP as a clinical marker in chronic renal disease. Urinary L-FABP was measured in patients with nondiabetic chronic renal disease (n = 120) with the use of a newly established ELISA method. We then monitored these patients for 15 to 51 months. Clinical data were analyzed with multivariate analysis. Urinary L-FABP was correlated with urinary protein, urinary alpha(1)-microglobulin, and serum creatinine concentrations. Urinary L-FABP at the start of follow-up (F = 17.1, r =.36, P <.0001) was selected as a significant clinical factor correlated with the progression rate, defined as a slope of a reciprocal of serum creatinine over time. We next selected the patients with mild renal dysfunction (n = 35) from all 120 patients and divided them into 2 groups according to progression rate: the progression group (n = 22) and the nonprogression group (n = 13). Serum creatinine and urinary protein concentrations and blood pressure at the start of follow-up were higher in the progression group than in the nonprogression group, although we detected no significant difference between the 2 groups. Urinary L-FABP was significantly higher in the former group than in the latter (P <.05). The results showed that urinary L-FABP reflected the clinical prognosis of chronic renal disease. Urinary L-FABP may be a clinical marker that can help predict the progression of chronic glomerular disease.
authors.affiliation: Second Department of Internal Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Kamijo
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Kimura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sugaya
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamanouchi
authors.forename: Akihisa
authors.initials: A
authors.lastname: Hikawa
authors.forename: Norihito
authors.initials: N
authors.lastname: Hirano
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Hirata
authors.forename: Atsuo
authors.initials: A
authors.lastname: Goto
authors.forename: Masao
authors.initials: M
authors.lastname: Omata
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D015415:Biomarkers / Q000652:urine*; D001706:Biopsy; D002352:Carrier Proteins / Q000276:immunology / Q000652:urine*; D003404:Creatinine / Q000097:blood; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000473:pathology / Q000652:urine*; D008099:Liver / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000652:urine; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011507:Proteinuria; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000652:urine; D025521:Tumor Suppressor Proteins
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D002352:Carrier Proteins; C493319:FABP1 protein, human; C107608:FABP7 protein, human; C493320:Fabp1 protein, mouse; C082667:Fabp5 protein, mouse; C086936:Fabp7 protein, mouse; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; C109148:SPINT2 protein, human; D025521:Tumor Suppressor Proteins; D014360:Trypsin Inhibitor, Kunitz Soybean; D003404:Creatinine