Measurement of dermal collagen synthesis rate in vivo in
humans.
El-Harake, Wassim A., Mikhail A. Furman, Brian Cook, K. Sreekumaran
Nair, Jayme Kukowski, and Irwin G. Brodsky.
Departments of Medicine, Dermatology, and Human Nutrition,
University of Illinois at Chicago, Chicago, IL 60612, and Department
of Medicine and General Clinical Research Center, Mayo Clinic,
Rochester, MN 55905
APStracts 4:0284E, 1997.
Accumulation of collagen produces organ dysfunction in many
pathological conditions. We measured the fractional synthesis rate
(FSR) of dermal collagen in five human volunteers from the increment
of 13C-proline in detergent soluble dermal collagen hydroxylated to
hydroxyproline during a continuous infusion of L-[1-13C]-proline. In
these and 8 other volunteers, we measured 13C-proline enrichment in
skin amino acyl tRNA, skin tissue fluid amino acid, and plasma. The
13C-prolyl tRNA enrichment was half that in tissue fluid proline and
more than 3-fold less than in plasma. The FSR of dermal collagen was
0.076 +/- 0.063 %/h (mean +/- SD), similar to previously reported
rates for skeletal muscle contractile proteins and substantially
slower than hepatically derived circulating proteins such as albumin
or fibrinogen . We conclude that the FSR of human dermal collagen
resembles that of other human proteins considered to display slow
turnover. The current method for its measurement may be used to
determine the regulation of collagen synthesis in other organs and
disease states.
Received 28 June 1997; accepted in final form 18 December 1997.
APS Manuscript Number E307-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 7 January 1998