Urine glycyl-L-proline increase and skin trophicity.
Glycyl-L-proline (gly-pro) is an end product of collagen metabolism that is further cleaved by prolidase (EC 3.4.13.9); the resulting proline molecules are recycled into collagen or other proteins. We postulated a relationship between defective gly-pro hydrolysis, increased collagen degradation and skin destruction. This relationship was tested using HPLC to measure the gly-pro in urine. 24 hour urine samples were collected from 27 old people (86 +/- 6 years old), of whom 15 were suffering from skin pressure sores of the sacrum or calcaneus. The urine from patients with pressure sores contained significantly more gly-pro than the urine from the control. A cut-off at 7 mumol/mmol creatinine gave the test a positive predictive value of 70%. Collagen breakdown was also increased as indicated by the increase of hydroxyproline (hyp) in the urine. But this breakdown seemed to stop at the gly-pro step.
Le
J
J
Laboratoire de Biochimie, Faculté de Médecine, Saint-Etienne, France.
Perier
C
C
Peyroche
S
S
Rascle
F
F
Blanchon
M A
MA
Gonthier
R
R
Frey
J
J
Chamson
A
A
D000368:Aged; D000369:Aged, 80 and over; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003094:Collagen / Q000378:metabolism; D004151:Dipeptides / Q000652:urine*; D006801:Humans; D008297:Male; D003668:Pressure Ulcer / Q000652:urine*; D012867:Skin / Q000473:pathology*
D004151:Dipeptides; C015248:glycylproline; D003094:Collagen