Urine Inositol Pentakisphosphate 2-kinase and Changes in Kidney Structure in Early Diabetic Kidney Disease in Type 1 Diabetes.

We examined the association of urine inositol pentakisphosphate 2-kinase (IPP2K) with the presence and progression of diabetic kidney disease (DKD) lesions. Urine IPP2K was measured at baseline by quantitative liquid chromatography mass spectrometry in 215 participants from the Renin-Angiotensin System Study who had type 1 diabetes and were normoalbuminuric and normotensive with normal or increased glomerular filtration rate (GFR). Urine IPP2K was detectable in 166 participants. Participants with IPP2K below the limit of quantification (LOQ) were assigned concentrations of LOQ/√2. All concentrations were then standardized to urine creatinine concentration. Kidney morphometric data were available from biopsies at baseline and after 5 years. Relationships of IPP2K/Cr with morphometric variables were assessed by linear regression after adjustment for age, sex, diabetes duration, HbA1c, mean arterial pressure, treatment assignment and, for longitudinal analyses, baseline structure. Baseline mean age was 29.7 years, mean diabetes duration 11.2 years, median AER 5.0 μg/min, and mean iohexol GFR 129 ml/min/1.73m². Higher IPP2K/Cr was associated with higher baseline peripheral glomerular total filtration surface density [Sv(PGBM/glom), tertile 3 vs. tertile 1 β=0.527, P=0.011] and with greater preservation of Sv(PGBM/glom) after 5 years (tertile 3 vs. tertile 1 β=0.317, P=0.013). Smaller increases in mesangial fractional volume (tertile 3 vs. tertile 1 β=-0.578, P=0.018) were ...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research