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J Aikawa

Publications and source records attributed to J Aikawa.

70 records · Page 4Linked to original sources

Isolation and characterization of a high-molecular-weight glycoprotein from the endometrium of porcine uteri.

A novel glycoprotein was isolated from the endometrium of porcine uteri. This high-molecular-weight glycoprotein consisted of 25% of protein and 73% of carbohydrate. The carbohydrate composition was quite characteristic in that equimolar N-acetylglucosamine and galactose were major constituents. Its unique nature makes it distinguishable from hitherto-reported glycoproteins.

Amino Acids↗

Isolation and characterization of a blood group active glycopeptide from porcine aorta.

A fucose-rich glycopeptide was prepared from the pronase digest of porcine thoracic aorta by gel-filtration through Sephadex G-100, DEAE-Sephadex A-25 column chromatography and alpha-amylase digestion. This glycopeptide was electrophoretically homogeneous. The large molecular size and chemical composition suggested that this glycopeptide was derived from mucin-type glycoprotein. The results of the beta-elimination reaction indicated that this glycopeptide contained the O-glycosidic linkages between galactosamine and serine/threonine. This glycopeptide exhibited blood group A and H activities. The present study revealed that the porcine thoracic aorta contains a blood group antigen of mucin-type glycoprotein nature.

Animals↗

Sulfated glycopeptides, containing desmosine and isodesmosine, isolated from porcine aorta.

Intima-media of porcine thoracic aorta was digested with pronase, after extraction of saline-soluble matters and fat. A crude sulfated glycopeptide fraction (CSGP) was precipitated with 90% (v/v) ethanol from the 80% ethanol-soluble fraction of the trichloroacetic acid (7%)-soluble fraction of the pronase digest. CSGP was fractionated by DEAE-Sephadex A-25 (Cl- form) column chromatography. Of the resulting 9 fractions, 4 major fractions were further purified by gel filtration on Sephadex G-50, followed by affinity chromatography on concanavalin (Con) A-Sepharose 4B to a homogeneous state in electrophoresis on cellulose acetate membrane. All the purified fractions contained glucosamine, galactose, mannose, and sialic acid as the major sugars, and desmosine and isodesmosine as the unique constituents. The fractions with affinity for Con A (S1 and S2) contained much more mannose than those without affinity for this lectin (S3 and S4). The latter contained sulfate. The predominant amino acids in the former were glycine, aspartic acid (and/or asparagine), and serine, while those in the latter were glycine, proline, and alanine.

Amino Acids↗

Glycosaminoglycans from renal brush border membranes of rabbits.

Brush border membranes were prepared from the rabbit kidney cortex by sucrose density gradient centrifugation and digested with pronase. A glycosaminoglycan fraction was isolated from the digest by ion-exchange chromatography. Electrophoretogram on cellulose acetate membrane (Separax) of the glycosaminoglycan fraction indicated the presence of two components, which were identified as chondroitin sulfate A/C and dermatan sulfate on the basis of their mobility in Separax electrophoresis and sensitivity to chondroitinase ABC. Neither hyaluronic acid nor heparan sulfate was detected. The results of high-performance liquid chromatography of the pyridylamino derivatives of unsaturated disaccharides in the digests with chondroitinase AC and ABC of the glycosaminoglycan fraction indicated that the ratio of chondroitin 4-sulfate, chondroitin 6-sulfate and dermatan sulfate was 5.5 : 1.0 : 9.1.

Animals↗

Unusual low affinity of human liver fibronectin for gelatin.

Fibronectin extracted from the human livers was shown to have very low affinity for gelatin unlike plasma fibronectin. It was demonstrated that this unusual property of liver fibronectin was not due to its proteolytic fragmentation.

Chromatography, Affinity↗

Sulfated glycopeptides from middle ear effusions of secretory otitis media.

The middle ear effusion specimens were obtained by myringotomy and aspiration from 4 children of 4-7 years old, who had been diagnosed as patients with secretory otitis media on the basis of conductive hearing loss and tympanogram. In cases 1 and 2, their ear fluids were macroscopically serous, while those of cases 3 and 4 were mucous. These ear fluids were digested with pronase and the digests were analyzed by cellulose acetate membrane electrophoresis with alcian blue and high-iron-diamine stainings. All samples were found to contain glycopeptides possibly derived from sulfated mucin-type glycoproteins with small amounts of glycosaminoglycans. The glycoconjugates from cases 3 and 4 were further examined after hyaluronidase and chondroitinase ABC treatments, followed by heparitinase digestion. The resultant glycopeptide fractions appeared to be electrophoretically homogeneous and their chemical compositions suggested that they were typical mucin-type glycopeptides. Furthermore, they contained sulfates. The data suggest that in secretory otitis media, one of the major components of middle ear effusions is sulfated mucin-type glycoprotein.

Amino Acids↗

Evidence for the occurrence of lactosaminoglycan in porcine kidney.

Weakly acidic glycopeptides were obtained from he pronase digest of porcine kidney. The glycopeptides were digested with endo-beta-galactosidase. An oligosaccharide fraction was separated from the digest by gel-filtration through Sephadex G-50. The fraction contained galactose and glucosamine in an equimolar ratio.

Amino Sugars↗

N-sulfation of heparan sulfate with microsomal fraction of endometrium of rabbit uterus.

Heparan sulfate was prepared from the pronase digest of the porcine kidney and modified chemically to yield N-desulfated, N-, O-desulfated, and N- O-desulfated N-acetylated heparan sulfates. Heparan sulfate and its modifications thus obtained were used as substrates to measure the sulfotransferase activity in the microsomal fraction of the endometrium of the rabbit uterus. N-, O-Desulfated heparan sulfate was the best acceptor of sulfate from 3'-phosphoadenylyl [35S] sulfate and intact heparan sulfate was the poorest one. The products of enzymatic reaction were treated with nitrous acid and examined by gel-filtration and electrophoresis. The results indicated that sulfate was almost exclusively incorporated as N-sulfate into all the present substrates.

Animals↗

Changes of glycosaminoglycan composition of uterine myometrium of rabbit induced by female sex steroids.

Glycosaminoglycan fractions were separately prepared from the myometrium of control, estrogen-treated, and estrogen-progesterone-treated rabbits after digestion with pronase. The glycosaminoglycan composition of each glycosaminoglycan fraction was determined by digestion with specific mucopolysaccharidases and nitrous acid. It was found that foregoing hormones showed no effects on the total glycosaminoglycan content, expressed as mg per g of the delipidated dry tissue. These hormones, however, markedly affected the glycosaminoglycan composition. As compared with the control, the estrogen-treatment decreased the contents of hyaluronic acid and dermatan sulfate, but increased those of chondroitin 4- and 6-sulfates. The effect of estrogen on the content of hyaluronic acid was strikingly enhanced by subsequent treatment with progesterone, and those of chondroitin 4- and 6-sulfates were also enhanced. On the other hand, progesterone abolished effect on the content of dermatan sulfate. Although no effect was observed on the content of heparan sulfate by the estrogen treatment, subsequent treatment with progesterone decreased the content of this glycosaminoglycan.

Animals↗

Further characterization of porcine plasma fibronectin which contains fucosylated carbohydrate chains.

Porcine plasma fibronectin and its functional four fragments produced by cathepsin B digestion were examined for biological, immunochemical and biochemical properties. Native fibronectin, 150-kDa and 130-kDa fragments exhibited similar cell attachment-promoting activity to each other. In an Ouchterlony double immunodiffusion system, these three polypeptides formed a precipitin line with anti-fibronectin antiserum, while the 50-kDa and 30-kDa fragments did not. The 150-kDa and 130-kDa fragments contained free sulfhydryl(s). The glycopeptide fractions were prepared by pronase digestion of porcine and human plasma fibronectin, and radiolabeled with [14C]acetic anhydride. The results of affinity chromatography with concanavalin A and lentil lectin immobilized on agarose indicated that the porcine glycopeptide fraction was different from the human fraction in that a larger part (58%) of the former was bound to lentil lectin. About 90% of this lentil lectin-reactive glycopeptides lost this reactivity upon alpha-L-fucosidase digestion. The glycopeptide fractions were also prepared from three carbohydrate-containing domains. Less than 30% of the radioactivity of the glycopeptide fractions of 150-kDa and 130-kDa fragments was retained on the lentil lectin-agarose, while about 90% of that from the 50-kDa fragment was retained. These results indicate that porcine plasma fibronectin has characteristics very similar to those of human plasma fibronectin and others, but is unique in that it contains fucosylated carbohydrate chains which unevenly distribute through functional domains.

Animals↗

Isolation and characterization of human placenta fibronectin.

Fibronectin was isolated from human placenta tissues and compared with human plasma fibronectin. Placenta and plasma fibronectins had similar amino acid compositions, immunological properties, and cell attachment-promoting activities, but differed in apparent molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which could be accounted for at least partly by the difference in carbohydrate composition. Unlike plasma fibronectin, placenta fibronectin failed to form a precipitin line with concanavalin A in a double diffusion system. The non- or low-reactivity of placenta fibronectin with this lectin was also demonstrated by affinity chromatography with concanavalin A-agarose, in which more than 90% of the radiolabeled glycopeptides derived from placenta fibronectin was not retained on the gel. The two fibronectins also differed in the reactivity with Lens culinaris agglutinin of their glycopeptide fractions. These data indicate that placenta and plasma fibronectins are different in their carbohydrate structures and, therefore, suggest the presence of a tissue- or cell-specific mechanism for processing the carbohydrates of this glycoprotein.

Amino Acids↗

Glycosaminoglycans of human colonic mucosa and colonic adenocarcinoma.

The mucosal scrapings of the normal human colons and the colonic adenocarcinoma tissues were digested with pronase, and the glycosaminoglycan fractions were prepared by fractionation with cetylpyridinium chloride after treatment with deoxyribonuclease. Chondroitin sulfate A/C, heparan sulfate, and hyaluronic acid were contained in the glycosaminoglycan fraction of the normal tissue, but dermatan sulfate was undetectable. In contrast, the glycosaminoglycan fractions derived from the tumors contained substantial amounts of dermatan sulfate together with the foregoing three glycosaminoglycans. The total content of glycosaminoglycans per wet tissue weight was elevated in the tumor tissues, which was consistent with histochemical findings.

Adenocarcinoma↗

Comparison of glycosaminoglycans from thoracic aortas of several mammals.

Intima-media of porcine, canine, rabbit, and human thoracic aortas were separately digested with pronase, after extraction of fat. Glycosaminoglycan fractions were then separated from the resulting glycoconjugate fractions by precipitation with cetylpyridinium chloride. Glycosaminoglycan compositions were determined by sequential digestion with Streptomyces hyaluronidase, chondroitinase AC, chondroitinase ABC and heparitinase 1. All the tissues contained hyaluronic acid, chondroitin sulfates AC, dermatan sulfate and heparan sulfate. Of these glycosaminoglycans, chondroitin sulfates AC were the most prominent ones. Relatively large proportions of heparan sulfate were contained in these tissues except for canine aorta. It is noteworthy that the proportions of glycosaminoglycans in the intima-media of rabbit and human thoracic aortas with similar maturation were quite similar, although those of others differed from each other.

Animals↗

Hormonal effects on glycosaminoglycans in thoracic aortas of rabbits.

Intima-media of thoracic aortas obtained from estrogen-treated, estrogen-progesterone-treated and sham-treated ovariectomized rabbits were separately digested with pronase after extraction of fat. Glycosaminoglycan fractions were then separated from the resulting glycoconjugate fractions by precipitation with cetylpyridinium chloride. The glycosaminoglycan levels increased after treatments with estrogen and estrogen-progesterone. Glycosaminoglycan compositions were determined by sequential digestion with Streptomyces hyaluronidase, chondroitinase AC, chondroitinase ABC and heparitinase 1. The proportions of dermatan sulfate and chondroitin sulfates AC increased after treatments with these hormones, while those of hyaluronic acid and heparan sulfate decreased. The changes of the proportions of dermatan sulfate and hyaluronic acid were dramatic. The changes of the glycosaminoglycan compositions with these hormones are thought to be an anti-atherosclerotic effect of these female hormones.

Animals↗

Acidic glycopeptides isolated from young human aortas.

Intima-media of young human thoracic aortas were digested with pronase, after extraction of saline-soluble matters and fat. Glycopeptide fractions were separated from the resulting glycoconjugate fractions by fractionation with cetylpyridinium chloride. Acidic glycopeptides (0.15 M Fr and 0.3 M Fr) were then isolated from the glycopeptide fractions by DEAE-Sephadex A-25 (Cl- form) column chromatography. They contained glucosamine, galactose, mannose and sialic acid as the major sugars and glucose as the minor one, although the proportions of these constituents differed from each other. In addition, galactosamine and fucose were the minor sugars in 0.3 M Fr and 0.15 M Fr, respectively. 0.3 M Fr contained much more sulfate and amino acids than 0.15 M Fr. Aspartic acid, proline, glycine, threonine, glutamic acid, valine, serine and alanine were the major amino acids, amounting to 82-89% in total, in these acidic glycopeptides, although their contents differed from each other. It is noteworthy that the proportions of the constituents in the corresponding fractions from young boy and girl with the same age showed similar trend. Although the data indicated the heterogeneity of the carbohydrate and peptide chains of the acidic glycopeptides, the degree of the heterogeneity is smaller than that of sialoglycopeptides isolated previously from aged human aortas.

Aged↗

Effect of captopril on acetylcholine-induced relaxation in the presence of nitroglycerin tolerance in isolated rabbit aorta.

We investigated the effects of angiotensin converting enzyme inhibitors on acetylcholine-induced endothelium-dependent vasodilation in the presence of nitroglycerin tolerance in rings of rabbit thoracic aorta mounted in tissue baths and precontracted with 10(-6) M norepinephrine. The vasorelaxant effects of acetylcholine were measured before and after 1 h treatment with 5 x 10(-4) M nitroglycerin. The acetylcholine dose-response curve shifted to the right after the induction of nitroglycerin tolerance. Pretreatment with captopril (a sulfhydryl angiotensin converting enzyme inhibitor), but not with M-1 (a metabolite of delapril and a nonsulfhydryl angiotensin converting enzyme inhibitor) restored acetylcholine-induced relaxation. Pretreatment with N-acetylcysteine also restored reduced acetylcholine-induced relaxation. These results suggest that the sulfhydryl group plays a major role in restoration of reduced acetylcholine-induced vasodilation in the presence of nitroglycerin tolerance.

Acetylcholine↗