Tamm-Horsfall glycoprotein: role in inhibition and promotion of renal calcium oxalate stone formation studied with Fourier-transform infrared spectroscopy.
Tamm-Horsfall glycoprotein (THP) from healthy probands inhibits the precipitation of calcium oxalate, whereas THP from individuals who repeatedly develop calcium oxalate stones has no effect or even promotes precipitation. Using Fourier-transform infrared spectroscopy, we found a structural differentiation between these functionally different THPs: a decisive difference in sialic acid content. Quantitative analysis for sialic acid showed the same results. THP from healthy probands had a high sialic acid content (51 +/- 9 g/kg), whereas THP from recurrent stone formers had a decreased sialic acid content (21 +/- 4 g/kg). This explains the dual role of THP in the precipitation of calcium oxalate and the formation of renal stones and shows the importance of glycosylation in the function of this glycoprotein.
Knörle
R
R
Department of Physical Chemistry, University of Freiburg, Germany.
Schnierle
P
P
Koch
A
A
Buchholz
N P
NP
Hering
F
F
Seiler
H
H
Ackermann
T
T
Rutishauser
G
G
D002129:Calcium Oxalate; D006801:Humans; D007669:Kidney Calculi / Q000209:etiology* / Q000517:prevention & control; D009088:Mucoproteins / Q000737:chemistry / Q000502:physiology*; D019158:N-Acetylneuraminic Acid; D012016:Reference Values; D012794:Sialic Acids / Q000032:analysis; D017550:Spectroscopy, Fourier Transform Infrared; D058949:Uromodulin
D009088:Mucoproteins; D012794:Sialic Acids; C548612:UMOD protein, human; D058949:Uromodulin; D002129:Calcium Oxalate; D019158:N-Acetylneuraminic Acid