Neutrophil gelatinase-associated lipocalin as an early biomarker of nephropathy in diabetic patients

Kidney Blood Press Res. 2009;32(2):91-8. doi: 10.1159/000209379. Epub 2009 Mar 24.


Background/aims: Renal tubulointerstitium plays an important role in the development and progression of diabetic nephropathy.

Methods: With the present study, we aimed at evaluating the levels of neutrophil gelatinase-associated lipocalin (NGAL), a tubular stress protein, in serum (sNGAL) and urine (uNGAL) from a cohort of 56 patients with type 2 diabetes mellitus categorized into three groups (normoalbuminuria, microalbuminuria and diabetic nephropathy).

Results: All groups showed increased NGAL values with respect to controls; interestingly, increased NGAL levels were already found in diabetic patients without early signs of glomerular damage (normoalbuminuric). Both sNGAL and uNGAL increased in parallel with the severity of renal disease, reaching higher levels in patients with manifest diabetic nephropathy. The assessment of Pearson coefficient evidenced significant relationships between sNGAL and, respectively, uNGAL, serum creatinine and GFR (inversely) and between uNGAL and, respectively, serum creatinine, proteinuria, albuminuria, serum albumin and GFR (both inversely).

Conclusions: NGAL might play an important role in the pathophysiology of renal adaptation to diabetes, probably as a defensive mechanism aiming to mitigate tubular suffering. Furthermore, NGAL measurement might become a useful and noninvasive tool for the evaluation of renal involvement in diabetic patients as well as for the early diagnosis of incipient nephropathy.

Publication types

  • Comparative Study

MeSH terms

  • Acute-Phase Proteins / urine*
  • Adult
  • Biomarkers / blood
  • Biomarkers / urine
  • Cohort Studies
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / diagnosis
  • Diabetes Mellitus, Type 2 / urine*
  • Diabetic Nephropathies / blood*
  • Diabetic Nephropathies / diagnosis
  • Diabetic Nephropathies / urine*
  • Female
  • Humans
  • Kidney Tubules / chemistry
  • Kidney Tubules / metabolism
  • Lipocalin-2
  • Lipocalins / blood*
  • Lipocalins / urine*
  • Male
  • Middle Aged
  • Proto-Oncogene Proteins / blood*
  • Proto-Oncogene Proteins / urine*
  • Time Factors


  • Acute-Phase Proteins
  • Biomarkers
  • LCN2 protein, human
  • Lipocalin-2
  • Lipocalins
  • Proto-Oncogene Proteins