Acid Mucopolysaccharide Composition Research Articles

Gas-liquid chromatographic analysis of the monosaccharide composition of acid glycosaminoglycans (mucopolysaccharides) derived from animal tissues

Quantitative, gas-liquid chromatography was investigated for analysis of the monosaccharide composition of acid mucopolysaccharides from animal tissues. The method entailed the analysis of the trimethylsilyl (Me 3Si) derivatives of methyl glycosides on two liquid phases. Good resolution of monosaccharides was achieved by use of columns of SE-30 and Apiezon-M. The procedure was tested with chondroitin 4-sulfate, and the results were slightly different from those of Mathews et al. When the analysis is performed according to this method, important points are:(1) absolutely anhydrous, methanolic hydrogen chloride is necessary, to ensure detection of hexosamines and sialic acid; and (2) high moisture in the air obstructs high recovery of methyl glycosides and their Me 3Si derivatives, except in the case of neutral sugars.

The decreased synthesis of chondroitin sulfate-containing extracellular proteoglycans by SV40 transformed Balb/c 3T3 cells

Balb/c 3T3 cells synthesize 5--10 times more 35SO2/4- -labeled extracellular proteoglycan per cell than do Balb/c 3T3 cells transformed by SV40 (SV3T3). The extracellular 35SO2/4- -labeled proteoglycans of the Balb/c 3T3 and SV3T3 cells differ markedly in their acid mucopolysaccharide composition. Extracellular Balb/c 3T3 proteoglycans contain about 70--80% chondroitin sulfate, most of which is chondroitin 4-sulfate, and small amounts of heparan sulfate and/or heparin. On the other hand, extracellular SV3T3 proteoglycans contain 65-75% heparan sulfate and/or heparin and less than 15% chondroitin sulfate. Analysis of extracellular 35SO2/4- -labeled proteoglycan by sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveals that Balb/c 3T3 alone synthesizes a class of proteoglycans capable of migrating in a 10% separating gel. This class of proteoglycans, designated as fraction C, accounts for up to 45% of the total extracellular Balb/c 3T3 35 SO2/4- -labeled proteoglycans and contains chondroitin sulfate extracellular SV3T3 proteoglycans. The absence of this and other classes of chondroitin sulfate-containing proteoglycans can account for the 5-10-fold decreased synthesis of 35SO2/4- -labeled proteoglycans by SV3T3 cells when compared to Balb/c 3T3 cells.

Altersbedingte Konzentrationsänderungen saurer Mukopolysaccharide in der Mitralklappe des Menschen

The acid glycosaminoglycans of human mitral valves are differentiated histochemically by the critical electrolyte concentrations of alcian blue. Age- dependent changes in the composition of acid mucopolysaccharides in the ground substances of valves are investigated by histophotometric measurements between the free valve edge and the line of closure. With respect to these values, the concentration of the total acid mucopolysaccharides in mitral valves grows with aging. The first increase is seen until to the 4th decade, a second one with the 5th decade reaching its maximum in old age. Sulfomucopolysaccharides show similar variations; increasing until the 4th decade, they are followed by a slight decrease and new increasing until old age. The concentration of more alcianophilic chondroitin sulfates, however, reaches a maximum in the 4th decade, falling off in later life. No acid mucopolysaccharides of higher sulfation grade are detected in mitral valve ground substances. Hyaluronic acid represents the main part of acid mucopolysaccharides in mitral valves. With advancing age the content of hyaluronic acid grows at a rate equal to that of the total acid mucopolysaccharides and reaches its maximum concentration in the 8th and 9th decade. The chondroitin sulfates represents 20–22% of the total acid mucopolysaccharides. This ratio does not change substantially during the aging process.

Glycoprotein changes in diabetic kidneys.

A study of glycoproteins from renal cortical tissue from seventeen individuals with diabetes mellitus and four controls was performed. The diabetic tissues were divided, based on observations of the acid mucopolysaccharide composition from an earlier study, into three groups: seven showed a milder clinical course of diabetes and minimal histologic changes; five had severe clinical diabetes and predominantly nodular Kimmelstiel-Wilson lesions; and the remaining five had moderate to severe clinical diabetes with predominantly diffuse intercapillary glomerulosclerosis. In the latter two groups, a marked increase of neutral sugars was noted, particularly suggesting an increase in galactose-containing glycoprotein. Similarly, shifts to electrophoretically faster-moving glycoproteins and more intense PAS'staining were noted in severe diabetic changes. These observations suggest that there may be significant chemical changes in the nature of glycoproteins asociated with diabetes which may reflect on an uncontrolled metabolic defect of this disease.

Changes of acid mucopolysaccharides in the heart involved by amyloidosis

The acid mucopolysaccharide composition of cardiac tissue from 5 patients with amyloidosis and from control tissue was determined. Heparitin sulfate was consistently increased in the heart and other organs with amyloid deposition. (A corollary study of experimentally induced amyloidosis closely mimicked secondary amyloidosis in man, but in addition to the marked increase of heparitin sulfate in parenchymal organs, a slight increase of this mucopolysaccharide was observed in the heart as well.) In the myocardium, particularly with primary cardiac disease, hyaluronic acid was significantly increased. The observations of acid mucopolysaccharide chemistry in amyloidosis and in diabetic kidneys and the aorta suggest that heparitin sulfate arises from mesangial cells intimately involved in the formation of blood vessels and other cardiovascular structures. Hyaluronic acid, which also increases in the heart in forms of cardiac localization of amyloid, is probably part of the general connective tissue response of the cardiac tissue to disease.

The effect of nicotine on dietary atherogenesis in rabbits

Rabbits (New Zealand, albino, females) on a cholesterol (1%) diet and injected with nicotine (2.78 mg/kg 5 days a week for 6 weeks) demonstrated wider areas of involvement of the internal surface (9.4% vs. 5.7%) in the aorta than rabbits on a cholesterol diet alone. In both stock-fed and cholesterol-fed animals, nicotine produced an increase in aortic triglycerides and a decrease in the free cholesterol content. An increase in phospholipids, particularly in lecithin and cephalin, was observed in the cholesterol-fed rabbits treated with nicotine. Aortic acid mucopolysaccharide composition did not exhibit any significant changes following nicotine treatment. In experiments in vitro, it was shown that heparin and nicotine form a relatively stable complex, in a molar ratio of about 1:20; nicotine also inhibits the hydrolysis of 14C-labeled triolein in a homogenate from rabbit aortic tissue. It is suggested that some of the biological effects of nicotine may be the result of a complex formation between nicotine and heparin in vivo.

Hormonal effects on the acid mucopolysaccharide composition of the rat aorta

Summary Both thyroidectomized and methimazole-treated rats had lower concentrations of the sulfated acid mucopolysaccharides in their aortas. This decrease could be prevented or reversed by the administration of thyroxine. The same observations were made in hypophysectomized rats, and it was concluded that the acid mucopolysaccharide (AMPS) changes were due to a lack of thyroid hormone rather than to any changes in thyroid stimulating hormone (TSH) concentration. On the other hand, growth hormone specifically increased the chondroitin sulfate concentration in hypophysectomized rats, and this proceeded independently from the action of thyroxine. Cortisone decreased the amounts of chondroitin sulfate in rat aorta, but it had no effect upon the other AMPS fractions. Estradiol and testosterone administration as well as adrenalectomy and gonadectomy had no effect upon the aortic AMPS, and it was concluded that the rat aorta is mainly dependent upon thyroid hormone for the maintenance of its AMPS composition. The administration of methimazole prevented the accumulation of chondroitin sulfate in the aortas of lathyritic rats. This suggests that hypothyroidism decreases the biosynthesis of aortic AMPS.

Distribution and composition of acid mucopolysaccharides in normal and atherosclerotic human aortas

The relationship between tissue concentration and composition of the acid mucopolysaccharides (acid MPS) of the human aorta and the stage of atherosclerosis and/or age has been examined. Acid MPS have been analysed in the intima, the media, and excised atherosclerotic lesions from aortas at different stages of atherosclerosis. The analyses comprised the determination of the total acid MPS; the acid MPS that are digestible by testicular hyaluronidase, i.e. hyaluronic acid (HA) plus chondroitin sulphate C (CSA-C); the hyaluronidase-resistant MPS, i.e. heparitin sulphate (HS) plus chondroitin sulphate B (CSA-B), and the four components separately. The concentrations of total acid MPS (per dry defatted weight) vary according to kind of tissue and lesions, but show little correlation with the stage of atherosclerosis. The concentrations of resistant acid MPS are highest in the fatty streaks and spots and lowest in the ulcerated lesions. The concentration of HA decreases with increasing stage of atherosclerosis and/or ageing; that of HS shows a maximum at stage I; that of CSA-C is maximal at II; no correlation was found between CSA-B concentration and stage of the disease. A decreased permeability of the arterial wall and a decreased fibrinolytic activity consequent upon these changes in MPS composition are seen as possible factors in the development of atherosclerotic plaques.

14 Urinary Acid Mucopolysaccharides in Myxedema

Changes of the skin in myxedema are thought due to changes in its composition of acid mucopolysaccharides (AMPS). In the skin of the hypothyroid rat it has been shown that the content of hyaluronic acid is increased and the content of chondroitin sulfate decreased. A study of the changes in the urinary excretion of acid mucopolysaccharides in two children with acquired myxedema was carried out in order to gain more knowledge about the character of myxedema in humans. Twenty-four hour urines were collected on both children before and at the beginning of treatment with dessicated thyroid. AMPS were precipitated with cetyl trimethyl ammonium bromide and excretion expressed as mg of hexuronic acid/gm of creatinine. AMPS were then fractionated on columns of Dowex 1X2 (Cl-) and eluted with 6 stepwise gradients of NaCl. Components in each fraction were identified by microelectrophoresis on cellulose acetate, analysis of hexuronic acid, hexosamine and sulfate content and identification of the specific hexosamine by paper chromatography. Pretreatment total AMPS were normal for both children and remained so during initial treatment with dessicated thyroid. However, chromatographic fractionation of the pretreatment urinary AMPS yielded a product in the first fraction which is nearly identical in both children and which appears to be hyaluronic acid. Hyaluronic acid is not found in this fraction of AMPS from control urine in this laboratory. The results suggest that human myxedema also contains increased hyaluronic acid. (SPR)

Acid mucopolysaccharide composition of serous effusions. Study of 100 patients with neoplastic and non-neoplastic conditions.

Acid mucopolysaccharide composition of serous effusions. Study of 100 patients with neoplastic and non-neoplastic conditions.

Effect of age on the heparin content of rat skin.

IN 1955, Shetlar and Masters1 demonstrated a change with age in the composition of acid mucopolysaccharides of human cartilage. They found that both uronic acid and hexosamine decreased with age but the decrease in hexosamine was less striking, indicating a relative increase in some hexosamine-containing polysaccharide. Further evidence for a shift in the relative proportions of acid mucopolysaccharides in ageing cartilage was provided by Kuhn and Leppelmann2, who reported a decrease in the ratio of galactosamine to glucosamine. Recently, Kaplan and Meyer3 observed that the content of chondroitinsulphuric acid in human cartilage decreased and that of keratosulphate increased with age. On the basis of an increasing glucosamine to galactosamine ratio, Hallen4 concluded that the ratio of keratosulphate to chondroitinsulphuric acid in human nucleus pulposus increased with age. A difference in the distribution of mucopolysaccharides between embryonic and mature pig skin was reported by Loewi and Meyer5. They found that hyaluronic acid comprised 78 per cent of the total skin mucopolysaccharides in the embryo and only 30 per cent in the adult, whereas chondroitinsulphuric acid-B represented 5–12 per cent in embryonic skin and 64 per cent of total mucopolysaccharides in adult skin.