hydroxylysine and Chronic-Disease

To investigate age related and site specific variations in turnover and chemistry of the collagen network in healthy tendons as well as the role of collagen remodelling in the degeneration of the supraspinatus tendon (ST-D) in rotator cuff tendinitis.. Collagen content and the amount of hydroxylysine (Hyl), hydroxy-lysylpyridinoline (HP), lysylpyridinoline (LP), and the degree of non-enzymatic glycation (pentosidine) were investigated in ST-D and in normal human supraspinatus (ST-N) and biceps brachii tendons (BT-N) by high-performance liquid chromatography.. In BT-N, tendons that served as control tissue as it shows rarely matrix abnormalities, pentosidine levels rise linearly with age (20-90 years), indicating little tissue remodelling (resulting in an undisturbed accumulation of pentosidine). A similar accumulation was observed in ST-N up to 50 years. At older ages, little pentosidine accumulation was observed and pentosidine levels showed large interindividual variability. This was interpreted as remodelling of collagen in normal ST after age 50 years because of microruptures (thus diluting old collagen with newly synthesised collagen). All degenerate ST samples showed decreased pentosidine levels compared with age matched controls, indicating extensive remodelling in an attempt to repair the tendon defect. Collagen content and the amount of Hyl, HP, and LP of ST-N and BT-N did not change with age. With the exception of collagen content, which did not differ, all parameters were significantly (p < 0.001) lower in BT-N. The ST-D samples had a reduced collagen content and had higher Hyl, HP, and LP levels than ST-N (p < 0.001).. Inasmuch as Hyl, HP, and LP levels in ST-N did not change with age, tissue remodelling as a consequence of microruptures does not seem to affect the quality of the tendon collagen. On the other hand, the clearly different profile of post-translational modifications in ST-D indicates that the newly deposited collagen network in degenerated tendons is qualitatively different. It is concluded that in ST-D the previously functional and carefully constructed matrix is replaced by aberrant collagen. This may result in a mechanically less stable tendon; as the supraspinatus is constantly subjected to considerable forces this could explain why tendinitis is mostly of a chronic nature.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Amino Acids; Arginine; Child; Chronic Disease; Collagen; Cross-Linking Reagents; Humans; Hydroxylation; Hydroxylysine; Lysine; Middle Aged; Rotator Cuff; Tendinopathy

In patients with or without various chronic liver diseases, the total urinary excretion of hydroxyproline and hydroxylysine and the hepatic content of hydroxyproline were examined. In 7 patients without liver disease, the urinary excretion of hydroxyproline and hydroxylysine were 10.3 +/- 1.5 and 1.31 +/- 0.21 mmol/mol creatinine, respectively, and the hepatic content of hydroxyproline was 4.9 +/- 0.6 mumol/g of wet liver. In 33 patients with liver disease, the urinary excretion of hydroxyproline and hydroxylysine and the hepatic content of hydroxyproline were increased in proportion to the severity of liver disease. The hepatic content of hydroxyproline showed a significant correlation with the urinary excretion of hydroxyproline and hydroxylysine (r = +0.406 and r = +0.531, respectively). These results suggest that the study of urinary hydroxyproline and hydroxylysine excretion may yield useful information on the metabolism of hepatic collagen in chronic liver disease. Moreover, urinary hydroxylysine excretion seemed to be a better index of hepatic collagen metabolism than urinary hydroxyproline excretion; perhaps urinary hydroxylysine excretion is not much affected by dietary collagen intake.

Topics: Adult; Chronic Disease; Female; Hepatitis; Hepatitis, Chronic; Humans; Hydroxylysine; Hydroxyproline; Liver Cirrhosis; Male; Middle Aged

A method was established to isolate the glomeruli from the kidney fixed in formaldehyde. O-Hydroxylysylglycosides and hydroxyproline in the isolated glomeruli from the kidney of normal subjects, diabetics and subjects with chronic glomerulonephritis were measured on the alkaline hydrolyzate of the glomeruli. O-Hydroxylysylglycosides in 1000 glomeruli were 9.42 +/- 2.68 nmoles (mean +/- S.D.) for controls, 12.92 +/- 7.36 nmoles for diabetics and 12.54 +/- 4.62 nmoles for subjects with chronic glomerulonephritis. Hydroxyproline in 1000 glomeruli from control, diabetics and subjects with chronic glomerulonephritis was 43.0 +/- 10.7, 82.0 +/- 39.3 and 52.1 +/- 21.3 nmoles, respectively. Hydroxyproline in the hyalinized glomeruli from diabetics was 123.3 +/- 22.4 nmoles/1000 glomeruli, and significantly increased in comparison with that in the glomeruli from chronic glomerulonephritis or control subjects.

Topics: Adult; Aged; Chronic Disease; Diabetes Mellitus; Glomerulonephritis; Glycoproteins; Humans; Hydroxylysine; Hydroxyproline; Kidney Glomerulus; Middle Aged

Free hydroxylysine and hydroxylysing glycosides were separated from urine and serum extracts on cation exchange resin and assayed spectrophotometrically. The method in conjunction with gel filtration in Bio-Gel P2 allowed to separate from urine also polypeptide hydroxylysine and hydroxylysine bound in small molecules of neutral or acidic character. Glycosylgalactosylhydroxylysineand galactosylhydroxylysine were separated by partition and/or ion exchange chromatography. Patients with chronic renal insufficiency had elevated serum levels and urinary excretion of hydroxylysine glycosides with increased excretion of hydroxylysine bound in polypeptides and in small molecules of neutral or acidic character. The excretion of free hydroxylysine was often within normal limits. When compared to values found in normal growing subjects and in adult patients with increased bone turnover and normal renin function the urinary excretion of hydroxylysine glycosides in chronic uremia was more markedly increased than excretion of hydroxyproline polypeptides and total hydroxyproline.

Topics: Bone Diseases; Chemical Fractionation; Chronic Disease; Collagen; Glycosides; Humans; Hydroxylysine; Uremia