Subject(s)
Burns/therapy , Colonic Diseases/surgery , Intestinal Perforation/surgery , Accidents, Aviation , Adult , Burns/complications , Colectomy , Colonic Diseases/complications , Humans , Intestinal Perforation/complications , Male , Multiple Organ Failure/etiology , Wound Infection/drug therapy , Wound Infection/etiologyABSTRACT
Collagen from human skin was fractionated into neutral salt-soluble, acid-soluble, pepsin-released, and insoluble fractions. No age-related changes were observed in the proportion of collagen extracted by neutral salt. A significant age-related decrease in the proportion of acid-soluble collagen was found. A highly significant (P less than 0.001) age-related decrease in the amount of collagen released by pepsin digestion was observed, with a concomitant age-related increase in the fraction of insoluble collagen. The amount of ketoamine-linked glucose bound to this insoluble collagen also increased significantly with age. Skin collagen from three juvenile onset diabetics (JOD) and one young maturity onset diabetic (MOD) appeared to have undergone accelerated aging. JOD and the young MOD had significantly less collagen released by pepsin digestion and significantly more insoluble collagen than would be predicted by their ages. The collagen released by pepsin digestion of the diabetic samples had more high molecular weight components than similar fractions obtained from age-matched nondiabetic controls. There was also more ketoamine-linked glucose bound to the insoluble collagen of JOD than to that fraction from comparably aged control subjects. The apparent acceleration of collagen aging in diabetes mellitus may play a role in complications of diabetes that occur in collagen-rich tissues.
Subject(s)
Aging , Collagen/metabolism , Diabetes Mellitus/metabolism , Skin/metabolism , Adolescent , Adult , Aged , Collagen/analysis , Diabetes Mellitus, Type 1/metabolism , Electrophoresis, Polyacrylamide Gel , Glucose/analysis , Glucose/metabolism , Humans , Middle Aged , Pepsin A , SolubilityABSTRACT
Several of the characteristic complications of diabetes mellitus resemble age-like changes in collagen-rich tissues. It has been reported that increased glucosylation of hemoglobin and serum proteins occurs in diabetes. Glucosylation of insoluble human tendon collagen, a protein with little or no turnover was determined by a thiobarbituric acid method in 23 subjects as a function of age and the presence or absence of diabetes. Amounts of glucose and collagen solubilized by collagenase digestion of the samples were also determined. Glucosylation of collagen was found to increase with age and was markedly increased in juvenile onset diabetes. There appeared to be a limit to the amount of glucosylation that could occur, and older individuals with maturity-onset diabetes demonstrated glucosylation within that limit. The glucose nonenzymatically bound to human collagen may indicate the level of long-term control of the diabetes, and may play a role in the alteration of collagenous tissue properties that occurs in both aging and diabetes.