Urinary inhibitors of calcium oxalate crystallization and their potential role in stone formation

1997 ◽  
Vol 15 (3) ◽  
pp. 155-164 ◽  
Author(s):  
R. L. Ryall
Nephrology ◽  
1984 ◽  
pp. 1025-1029
Author(s):  
Charles Y. C. Pak ◽  
John L. Meyer ◽  
Peter G. Werners ◽  
William B. Gill ◽  
Lawrence Resnick ◽  
...  

2021 ◽  
Vol 28 ◽  
Author(s):  
Priyadarshini ◽  
Abhishek Negi ◽  
Chetna Faujdar ◽  
Lokesh Nigam ◽  
Naidu Subbarao

Background: Human serum albumin (HSA) is one of the most abundant proteins in the blood plasma, urine as well as in the organic matrix of renal calculi. Macromolecules present in the urine modulate kidney stone formation either by stimulating or inhibiting crystallization process. Objective: In the present study, effect of HSA protein on the growth of calcium oxalate monohydrate crystal (COM) was investigated. Methods: Crystal growth assay was used to measure oxalate depletion in the crystal seeded solution in the presence of HSA. HSA concentrations exhibiting effect on crystal growth were selected for FTIR and XRD analysis. In silico docking was performed on seven different binding sites of HSA. Results: Albumin is playing dual role in growth of calcium oxalate crystallization. FTIR and XRD studies further revealed HSA exerted strain over crystal thus affecting its structure by interacting with amino acids of its pocket 1. Docking results indicate that out of 7 binding pocket in protein, calcium oxalate interacts with Arg-186 and Lys-190 amino acids of pocket 1. Conclusion: Our study confirms the role of HSA in calcium oxalate crystallization where acidic amino acids arginine and lysine are binding with COM crystals, revealing molecular interaction of macromolecule and crystal in urolithiasis.


2007 ◽  
Vol 293 (6) ◽  
pp. F1935-F1943 ◽  
Author(s):  
Lan Mo ◽  
Lucy Liaw ◽  
Andrew P. Evan ◽  
Andre J. Sommer ◽  
John C. Lieske ◽  
...  

Although often supersaturated with mineral salts such as calcium phosphate and calcium oxalate, normal urine possesses an innate ability to keep them from forming harmful crystals. This inhibitory activity has been attributed to the presence of urinary macromolecules, although controversies abound regarding their role, or lack thereof, in preventing renal mineralization. Here, we show that 10% of the mice lacking osteopontin (OPN) and 14.3% of the mice lacking Tamm-Horsfall protein (THP) spontaneously form interstitial deposits of calcium phosphate within the renal papillae, events never seen in wild-type mice. Lack of both proteins causes renal crystallization in 39.3% of the double-null mice. Urinalysis revealed elevated concentrations of urine phosphorus and brushite (calcium phosphate) supersaturation in THP-null and OPN/THP-double null mice, suggesting that impaired phosphorus handling may be linked to interstitial papillary calcinosis in THP- but not in OPN-null mice. In contrast, experimentally induced hyperoxaluria provokes widespread intratubular calcium oxalate crystallization and stone formation in OPN/THP-double null mice, while completely sparing the wild-type controls. Whole urine from OPN-, THP-, or double-null mice all possessed a dramatically reduced ability to inhibit the adhesion of calcium oxalate monohydrate crystals to renal epithelial cells. These data establish OPN and THP as powerful and functionally synergistic inhibitors of calcium phosphate and calcium oxalate crystallization in vivo and suggest that defects in either molecule may contribute to renal calcinosis and stone formation, an exceedingly common condition that afflicts up to 12% males and 5% females.


1994 ◽  
Vol 87 (2) ◽  
pp. 137-142 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Villis R. Marshall ◽  
Rosemary L. Ryall

1. Increasing the concentration of dissolved urate promotes calcium oxalate crystallization in urine from which Tamm-Horsfall mucoprotein, an inhibitor of calcium oxalate crystal aggregation, has almost completely been removed. This study aimed to determine whether the effect of urate could be reduced or abolished by a physiological concentration of Tamm-Horsfall mucoprotein. This was approached in two ways. 2. The effect of Tamm-Horsfall mucoprotein on calcium oxalate crystallization induced by urate was tested in ultrafiltered (10 kDa) urine samples from 10 healthy men. Tamm-Horsfall mucoprotein (35 mg/l) was added to half of each specimen, the urate concentration was increased by the addition of sodium urate solution and crystallization was induced by a standard load of oxalate. The remainder of each urine specimen was used as a control; these specimens were treated with an identical amount of urate solution, but contained no Tamm-Horsfall mucoprotein. Tamm-Horsfall mucoprotein had no effect on the urinary metastable limit or on the deposition of calcium oxalate, but significantly reduced the size of the particles precipitated. 3. The effect of increasing the urate concentration in the presence of Tamm-Horsfall mucoprotein was tested. Tamm-Horsfall mucoprotein (35 mg/l) was added to 10 ultrafiltered urine samples as before, the samples were divided, and the concentration of urate was increased in half of each specimen. Compared with the control to which no urate was added, urate significantly reduced the amount of oxalate required to induce spontaneous calcium oxalate nucleation and increased the median volume and the particle size of the material deposited. 4. It was concluded that, in vivo, (a) hyperuricosuria would encourage the formation of calcium oxalate stones by promoting calcium oxalate crystallization, (b) Tamm-Horsfall mucoprotein would not lessen the effect of urate on calcium oxalate nucleation or bulk deposition but would reduce its effect on crystal aggregation; it could therefore reduce the likelihood of stone formation in patients with hyperuricosuria.


2000 ◽  
Vol 98 (4) ◽  
pp. 471-480 ◽  
Author(s):  
Caroline DEAN ◽  
Jerry KANELLOS ◽  
Hung PHAM ◽  
Maria GOMES ◽  
Adrian OATES ◽  
...  

The bikunin peptide chain of the protease inhibitor inter-α-inhibitor (∣α∣) has been reported to be an inhibitor of calcium oxalate (CaOx) crystallization, and hence has been proposed as having a role in CaOx kidney stone formation. However, further experimental evidence is required to assess if fragments of ∣α∣ other than bikunin may play a role in the regulation of crystallization events in stone formation. The aim of the present study was to assess the effects of ∣α∣ and several of its derivatives on CaOx crystallization in a seeded inorganic system and to compare these effects with those of a known inhibitor of crystallization, prothrombin. ∣α∣ was purified from a preparation of human plasma and fragmented by alkaline hydrolysis, and two of its peptide chains, bikunin and heavy chain 1 (H1), were purified further by HPLC. Their purity was confirmed by SDS/PAGE. Using Coulter counter and [14C]oxalate analysis and scanning electron microscopy, ∣α∣, its H1 chain and bikunin from urine and from plasma were shown to be relatively weak inhibitors of CaOx crystallization in vitro at expected physiological concentrations. It was concluded that members of the ∣α∣ family may not be as important in kidney stone formation as has been generally proposed, although further studies are required before a possible role for ∣α∣ and its fragments in stone formation can be unambiguously discounted.


1995 ◽  
Vol 2 (2) ◽  
pp. 81-86 ◽  
Author(s):  
Takuo Koide ◽  
Seiji Yamaguchi ◽  
Masato Utsunomiya ◽  
Toshiaki YoshiokaY ◽  
Kiyoshi Sugiyawia

Sign in / Sign up

Export Citation Format

Share Document