TY - JOUR
T1 - Crystal surface adhesion explains the pathological activity of calcium oxalate hydrates in kidney stone formation
AU - Sheng, Xiaoxia
AU - Ward, Michael D.
AU - Wesson, Jeffrey A.
PY - 2005
Y1 - 2005
N2 - Renal tubular fluid in the distal nephron of the kidney is supersaturated with calcium oxalate (CaOx), which crystallizes in the tubules as either calcium oxalate monohydrate (COM) or calcium oxalate dihydrate (COD). Kidney stones are aggregates, most commonly containing microcrystals of COM as the primary inorganic constituent. Stones also contain small amounts of embedded proteins, which are thought to play an adhesive role in these aggregates, and they often are found attached to the tip of renal papilla, presumably through adhesive contacts. Voided urine, however, often contains COD in the form of single micron-sized crystals. This suggests that COD formation protects against stone disease because of its reduced capacity to form stable aggregates and strong adhesion contacts to renal epithelial cells. Using atomic force microscopy configured with tips modified with biologically relevant functional groups, we have compared the adhesion strengths of the morphologically important faces of COM and COD. These measurements provide direct experimental evidence, at the near molecular level, for poorer adhesion at COD crystal faces, which explains the benign character of COD and has implications for resolving one of the mysteries of kidney stone formation.
AB - Renal tubular fluid in the distal nephron of the kidney is supersaturated with calcium oxalate (CaOx), which crystallizes in the tubules as either calcium oxalate monohydrate (COM) or calcium oxalate dihydrate (COD). Kidney stones are aggregates, most commonly containing microcrystals of COM as the primary inorganic constituent. Stones also contain small amounts of embedded proteins, which are thought to play an adhesive role in these aggregates, and they often are found attached to the tip of renal papilla, presumably through adhesive contacts. Voided urine, however, often contains COD in the form of single micron-sized crystals. This suggests that COD formation protects against stone disease because of its reduced capacity to form stable aggregates and strong adhesion contacts to renal epithelial cells. Using atomic force microscopy configured with tips modified with biologically relevant functional groups, we have compared the adhesion strengths of the morphologically important faces of COM and COD. These measurements provide direct experimental evidence, at the near molecular level, for poorer adhesion at COD crystal faces, which explains the benign character of COD and has implications for resolving one of the mysteries of kidney stone formation.
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U2 - 10.1681/ASN.2005040400
DO - 10.1681/ASN.2005040400
M3 - Article
C2 - 15930089
AN - SCOPUS:27744447545
SN - 1046-6673
VL - 16
SP - 1904
EP - 1908
JO - Journal of the American Society of Nephrology
JF - Journal of the American Society of Nephrology
IS - 7
ER -