Q.T. Smith

Urinary hydroxyproline: Creatinine ratio of normal humans at various ages

Abstract The urinary hydroxyproline excretion from normal individuals ranging from birth to 70 years of age has been expressed as milligrams hydroxyproline to milligrams creatinine excreted per 24 hours. The ratio of hydroxyproline: creatinine corrects at least partially for differences in body size between individuals, yielding a narrower range of values than the range of the urinary hydroxyproline values alone. A definite relationship of the ratio with age was found: increasing from birth to one month of age, decreasing from six months to about five years of age, remaining constant to puberty, decreasing again to about age twenty, and subsequently remaining constant through age 70 years. At all ages the ratio is essentially equivalent in both sexes and the variability of the ratio between individuals was much less than that of the corresponding 24-h urinary hydroxyproline values. In the same individual, the variation of the ratio determined on multiple samples was also less than the variation observed in the 24-h urinary hydroxyproline from the same specimens. Possible application and advantages of the use of the hydroxyproline: creatinine ratio are discussed. Comprehensive urinary hydroxyproline excretion values are given for normal infants from birth to one month of age.

Radioactivity of hydroxyproline from urine and collagens of normal and cortisone-treated rats

Abstract Twelve weanling male rats each received 15μc of l -proline- 14 C in 3 equal and consecutive daily i.p. injections. Fourteen days after the third isotope injection, 4 of the animals were sacrificed (0-day control). Four of the remaining rats each received 9 daily injections of 10 mg cortisone acetate/kg body wt. and then were sacrificed with the other animals (9-day control) 24 hr after the final steroid injection. Salt-soluble skin collagen represented a significantly lower fraction of the total skin collagen in the cortisone-treated rats than in the 9-day control animals. The sp. act. of hydroxyproline from salt-soluble skin collagen, mature skin collagen, and total femur collagen from the cortisone-treated rats were each significantly greater than those of the 9-day control animals. The mean urinary hydroxyproline excretion of the steroid-treated rats was significantly less after 4 days of treatment until termination of the experiment. Slightly greater urinary hydroxyproline specific activities of the cortisone-treated rats reflected the higher sp. act. of the collagen hydroxyproline pool of the steroid-treated rats. No significant differences were observed between the 24-hr urinary hydroxyproline radio-activities of control and cortisone-treated rats. The above observations, in conjunction with additional data given in this report and the findings of earlier experiments, were interpreted as providing further evidence in agreement with anti-anabolic changes in collagen metabolism (decreased collagen synthesis) resulting from the administration of pharmacologie quantities of cortisone to rats which would normally undergo rapid body growth. Although the data from the various experiments indicate that the steroid had an anticatabolic effect on femur collagen (decreased collagen degradation), urinary hydroxyproline excretions and radioactivities were inconclusive for the demonstration of an anticatabolic effect of the hormone on the total body pool of collagen.

Cutaneous collagen and hexosamine and femur collagen of testosterone propionate-treated rats of various ages

Abstract Body weight, collagen per total skin, hexosamine per total skin, hexosamine-to-collagen ratios of the total skin, and collagen per femur were determined in normal and in testosterone propionate-treated (1 to 21 daily injections) weanling, young adult, and adult male and female rats. Differences with age and sex in the response of the substances measured to testosterone propionate were observed. The body weight of the testosterone propionate-treated male rats was not significantly greater than that of the control rats at any experimental period, but in each age group of female rats, the testosterone propionate treatment resulted in significantly increased body weights at certain experimental periods. An anabolic effect from testosterone propionate on collagen was observed only in the skin and femur collagen of the weanling female rats. The response of skin and femur collagen to testosterone propionate was different in some experimental groups. The hexosamine-to-collagen ratios did not indicate a consistent and significant change in the amount of hexosamine-containing substances of the ground substance (acid mucopolysaccharides and mucoproteins) relative to fibers (collagen) in the skin of either male or female testosterone propionate-treated rats.

Inhibition of human salivary and prostatic acid phosphatase and yeast enolase by low fluoride concentrations.

Summary A study was made of the effects of low concentrations of fluoride on activity of salivary and human prostate acid phosphatase and yeast enolase. Concentrations of fluoride or concentrations that could be derived from fluoridation of drinking water did not significantly alter enzymatic activity. The straight line relationship between the logarithms of low fluoride concentrations and logarithms of percent of enzyme activity remaining suggested that it is possible to analyze fluoride content of pure aqueous solutions by degree of inhibition of activity of acid phosphatase of human prostate tissue.

Red Cell Glutathione and Glutathione Reductase in Cystic Fibrosis

Summary Red blood cell glutathione reductase and whole blood total (oxidized and reduced) glutathione were assayed in cystic fibrosis subjects and non-cystic fibrosis controls. Glutathione reductase activity and total glutathione levels were greater in the cystic fibrosis sample. These findings are consistent with previous data reporting increased pentose phosphate pathway activity and decreased NADPH/NADP ratios in cystic fibrosis erythrocytes. They support the notion that pentose phosphate pathway alterations occur in cystic fibrosis. These data may indicate also the possible role of sulfhydryl group changes in membrane transport abnormalities of the disease.

Application of a rapid and reliable method for determination of hexosamine in the skin of estrogen-treated rats☆

Abstract A procedure which allows rapid and reproducible quantitation of hexosamine in tissue hydrolyzates has been devised. Elimination of specific tedious and cumbersome details from previously reported procedures results in an efficient and reliable method for hexosamine determination. The improved method was employed for the determination of skin hexosamine of estradiol benzoate treated and control rats. Differences were demonstrated in the quantity of hexosamine in dry fat-free skin and in total skin of male and female estradiol benzoate treated rats.

Serum Glutathione Reductase and Cystic Fibrosis

Extract: Serum glutathione reductase (NADPH:GSSG oxidoreductase, EC. 1.6.4.2 (GR)) has been examined in cystic fibrosis subjects (CF), obligate CF heterozygotes, and control subjects. Serum protein concentration was similar in the three groups. Regardless of the units used to express activity (milligrams of protein or milliliters of serum) or whether or not samples were dialyzed against water or phosphate buffer, mean serum GR in CF was greater than in control subjects (P ≤ 0.002) in all series over several years. Under the above assay conditions no difference in serum GR between control subjects and carriers was detected. Calculated and assayed values of combined control and CF sera agreed as did expected and observed 50% activity in 1:2 sera dilutions in CF, control subjects, and carriers. Addition of FAD to incubation media did not effect enzyme activity in the three groups. Differences between CF and control subjects persisted after dialysis in membranes permitting passage of molecules of approximately 12,000 mol wt or less. These findings would tend to exclude the effect of extraneous serum factors in explaining the differences between CF and control subjects. The percentage of initial GR activity after four days storage (0-4°) was significantly greater in CF than in control subjects (P < 0.025). The effect of heparin on serum GR was recorded as the percentage of activity after incubation with heparin vs. activity in the standard assay for individual subjects. The effect of incubation with 5 μg/ml heparin on serum GR activity was greater in control subjects than in carriers (P < 0.0005) and CF (P < 0.0005). Mean serum GR activity in CF and carriers was unaffected by heparin, whereas mean activity in control subjects was decreased. In no control was the percentage of initial activity with heparin greater than the mean of CF and carrier groups. Only 3 of 20 CF and 4 of 20 carrier individuals had percentages lower than the control mean. The CF and carrier distributions were clearly different from the control distribution. Serum GR was determined in seven non-CF individuals with chronic obstructive pulmonary disease (COPD). Activity in the COPD was different from CF and no different from control subjects. In none of these controls or COPD was serum GR as great as the CF mean. Serum GR in no CF was as low as the mean of control subjects or COPD. It is concluded that serum GR activity is greater in CF than in control subjects, carriers, and non-CF COPD subjects; that the difference in activity is not attributable to an extraneous serum factor, that the activity difference is not secondary to chronic respiratory disease; that in comparison with control subjects, GR from CF serum behaves differently after storage; and that serum GR from CF and carriers behaves differently from control GR in the presence of heparin.Speculation: Abnormal activity of glutathione reductase may be fundamentally related to the pathogenesis of cystic fibrosis.

Biochemical Composition of Rat Costal Cartilage Prior to and During Calcification

Summary The ash, calcium and phosphorus contents of rat costal cartilage began to increase subsequent to 20, 16 and 18 days of age, respectively. However, at termination of the experiment (49 days of age), the quantities of the above 3 substances in costal cartilage were still much less than in rib bone. The amounts of collagen, hexosamine and uronic acid in rat costal cartilage had different relationships to animal age. No consistent relationships were observed among changes in the quantities of organic and inorganic cartilage components.

Isolation of radiocarbon-labeled glycine as glycine copper picrate from collagen☆

Abstract Methodology has been developed which permits the concurrent isolation and determination of the specific activity of radiocarbon-labeled glycine from a large number of connective tissue samples. Collagen is separated from other constituents of the tissues by conversion to gelatin, and the gelatin is then hydrolyzed with sulfuric acid. The acid in the hydrolyzate is neutralized with anion-exchange resin, and the glycine is then precipitated as glycine copper picrate complex. The glycine copper picrate complex is weighed and dissolved in distilled water. An aliquot of the solution is transferred to a special planchet and, following drying, its radioactivity is determined. Experimental results indicating validity of the procedure are described.

Cellular glycosaminoglycans in lymphocytes from patients with cystic fibrosis

Cellular glycosaminoglycans were isolated from lymphocytes from patients with cystic fibrosis and controls. The isolated glycosaminoglycans were fractionated by cellulose acetate electrophoresis, analyzed for glucosamine and galactosamine content, and subjected to hydrolysis with bovine testicular hyaluronidase. The total glycosaminoglycan content, the per cent glucosamine and galactosamine, and the distribution of cellular glycosaminoglycans in circulating lymphocytes in cystic fibrosis were no different from controls.