scholarly journals Incorporation of sulphate by chick-embryo corium. Nature and products of the process in vitro

1965 ◽  
Vol 97 (2) ◽  
pp. 432-439
Author(s):  
NL Noble ◽  
RJ Boucek

1. The incorporation of sulphate into the trichloroacetic acid-precipitable fraction of 9-day chick-embryo corium, incubated in Krebs-Ringer phosphate buffer, pH7, is dependent on the sulphate concentration of the medium. Uptake of sulphate is linear with time for 3.5-4hr. and is maximal at 37.5 degrees in the presence of air or oxygen. d-Glucose stimulates the incorporation of sulphate but l-glutamine has no effect. 2. Incorporation of sulphate by the chick corium is enzymic and apparently involves the synthesis of active sulphate (adenosine 3‣-phosphate 5‣-sulphatophosphate) and the transfer of sulphate from adenosine 3‣-phosphate 5‣-sulphatophosphate to acceptor glycosaminoglycuronoglycan. This proposal on the nature of the process is suggested by the similarity between the energy of activation calculated for sulphate-incorporation in the chick-corium preparation and the energy requirement reported for sulphate-activation with purified yeast enzymes. 3. The 9-day chick-embryo corium is composed principally of fibroblasts; there are no histologically demonstrable mast cells. The young fibroblast is apparently responsible for the incorporation of sulphate into glycosaminoglycuronoglycans tentatively identified as chondroitin sulphate(s), heparan sulphate and heparin-like material.

Zygote ◽  
2007 ◽  
Vol 15 (3) ◽  
pp. 225-232 ◽  
Author(s):  
A.-S. Bergqvist ◽  
J. Ballester ◽  
A. Johannisson ◽  
N. Lundeheim ◽  
H. Rodríguez-Martínez

SummaryGlycosaminoglycans (GAGs) are present in the oviduct in which the major part of sperm capacitation occurs. In this study we have tested how capacitation of frozen-thawed bull spermatozoa is effected by exposure to different GAGs detectable or possibly present in oviductal fluid; i.e. heparin, hyaluronan, heparan sulphate, dermatan sulphate and chondroitin sulphate. Following exposure of different duration, the spermatozoa were stained with either Chlortetracycline (CTC) or merocyanine-540 and evaluated with epifluorescent light microscopy or flow cytometry, respectively. Heparin elicited a significant increase in the number of alive, capacitated spermatozoa, either expressed as higher merocyanine-540 fluorescence (p < 0.0001) or as B-pattern (p = 0.0021) in the CTC assay, during 4 h of incubation. When comparing the different GAG treatments one by one to the negative control in the flow cytometric study, only heparin and dermatan sulphate were significant (p < 0.0001) higher than the control at 0–30 min of incubation. Duration of incubation did not affect the proportion of capacitated spermatozoa when measured as merocyanine-540 fluorescence or CTC B-pattern, but the length of the incubation did affect the number of dead (Yo-PRO 1 positive) spermatozoa (p < 0.0001). Exposure to zona pellucida proteins significantly increased the proportion of acrosome reacted spermatozoa (p = 0.016). Both heparin and dermatan sulphate induce capacitation of frozen-thawed bull spermatozoa in vitro.


1987 ◽  
Vol 241 (2) ◽  
pp. 591-601 ◽  
Author(s):  
M Sobue ◽  
H Habuchi ◽  
K Ito ◽  
H Yonekura ◽  
K Oguri ◽  
...  

A series of aryl and alkyl O-beta-D-xylosides and their analogues with S, NH or CH2 in the glycosidic linkage were prepared and examined for their ability to act as artificial chain initiators of chondroitin (dermatan) sulphate synthesis in embryonic chick cartilage, foetal rat skin and 6-week-old-rat aorta under conditions where normal protein-core synthesis was inhibited by cycloheximide. For all these tissues in culture, phenyl O-beta-D-xyloside and phenyl beta-D-thioxyloside were clearly more effective than the corresponding N-xyloside and homo-C-xyloside. Introduction of a carboxy group to the para position of their aglycone yielded derivatives with far lower initiator activity. In a concentration range lower than 0.1 mM, the effectiveness of alkyl beta-D-thioxyloside was greatly influenced by the carbon number (n) of the alkyl group and was at a maximum at n = 7 or 8 for the cartilage, at n = 5 for the skin and at n = 4 for the aorta. In the beta-xyloside-treated cartilages, the average length of newly formed chondroitin sulphate chains reflected the chain-initiator activity of added xyloside, i.e. the higher the initiator activity, the shorter the average chain length. In the skin and aorta, none of the drugs could relieve the inhibition of heparan sulphate synthesis caused by cycloheximide. Fertilized hens' eggs were each injected on day 9 with 9.2 mumol of beta-xyloside and the skeletal systems of embryos were examined a week later. The embryos treated with beta-xylosides of relatively high initiator activity showed a 30-40% decrease in the overall growth rate of skeletons, whereas those treated with beta-xylosides of low initiator activity showed little or no decrease in the growth rate. The results are consistent with the notion that the observed change in skeletal morphology results mainly, if not completely, from beta-xyloside-induced synthesis of core-protein-free chondroitin sulphate, and further suggest that a procedure employing a series of beta-xyloside homologues with various initiator activities will furnish an easily applied criterion on which to test the specificity of xyloside action on biological processes.


1985 ◽  
Vol 227 (3) ◽  
pp. 805-814 ◽  
Author(s):  
J A Robinson ◽  
H C Robinson

beta-Galactosides were found to initiate chondroitin sulphate chain synthesis in chick-embryo cartilage in vitro and thereby relieve inhibition by cycloheximide of [3H]-acetate incorporation into chondroitin sulphate. beta-Galactosides with an apolar aglycan group such as phenyl O-beta-galactoside were active, whereas those with a charged or polar aglycan group such as pyridine 3-O-beta-galactoside or those with sulphur instead of oxygen in the glycosidic linkage (phenyl beta-thiogalactoside) were not. beta-Galactosides also serve as substrates for microsomal galactosyltransferase activity from chick-embryo cartilage. Phenyl O-beta-galactoside and pyridine 3-O-beta-galactoside were effective substrates for this enzyme, but phenyl S-beta-thiogalactoside and pyridine 2-S-beta-thiogalactoside were only slightly active. This galactosyltransferase was shown to be a separate enzyme from galactosyltransferase I, which catalyses transfer of galactose from UDP-galactose to beta-xylosides. It is proposed that the enzyme catalysing this reaction is galactosyltransferase II, responsible for transfer of the second galactose residue of the chondroitin sulphate linkage oligosaccharide. No transfer of glucuronic acid from UDP-glucuronic acid to beta-galactosides, catalysed by the microsomal preparation could be detected.


1988 ◽  
Vol 251 (2) ◽  
pp. 411-418 ◽  
Author(s):  
L A Beavan ◽  
M Davies ◽  
R M Mason

Newly synthesized rat glomerular [35S]proteoglycans were labelled in vivo after injecting Na2[35S]SO4 intraperitoneally. At the end of the labelling period (7 h) the kidneys were perfused in situ with 0.01% (w/v) cetylpyridinium chloride. This fixed proteoglycans in the tissue and increased their recovery 2-3-fold during subsequent isolation of glomeruli from the renal cortex. The glomeruli were fractionated by a modified osmotic lysis and detergent extraction procedure [Meezan, Brendel, Hjelle & Carlson (1978) in The Biology and Chemistry of Basement Membranes (Kefalides, N.A., ed.), Academic Press, New York; Kanwar & Farquhar (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 4493-4497] to obtain a basement membrane preparation. The proteoglycans released at each stage of the procedure were characterized using DEAE-Sephacel ion-exchange chromatography, chondroitinase ABC and HNO2 digestion and Sepharose CL-4B gel-permeation chromatography. About 85% of the [35S]proteoglycans synthesized were of the heparan sulphate variety, the remainder being chondroitin sulphate proteoglycans. Three sizes of heparan sulphate proteoglycans were identified. The largest (HS1, Kav. 0.47) accounts for 44% of the total extractable heparan sulphates. About one third of HS1 were extracted from the glomerular basement-membrane fraction with 8 M-urea and 4 M-guanidine hydrochloride but the remainder were released from the glomerulus during preparation of the fraction. The two smaller molecules (HS2, Kav. 0.56 and HS3, Kav. 0.68) accounted for 27% and 28% of the extractable heparan sulphate respectively and were not associated with the basement membrane fraction. HS1, HS2 and HS3 were also isolated from non-fixed glomeruli labelled in vivo but with much lower recovery. In glomeruli labelled in vitro, heparan sulphate accounted for only 35% of the proteoglycans, the remainder being of the chondroitin sulphate type. Proteoglycans similar to HS1, HS2 and HS3 were present in glomeruli labelled in vitro but, in addition, a large, highly charged heparan sulphate (HS1a) was extracted from the glomerular basement-membrane fraction of these glomeruli. It accounted for 6% of the total heparan sulphate.


1995 ◽  
Vol 312 (1) ◽  
pp. 215-222 ◽  
Author(s):  
J Fischer

Tilorone (2,7-bis[2-(diethylamino)ethoxy]-fluoren-9-one) and several other bis-basic compounds are known to induce lysosomal glycosaminoglycan (GAG) storage. The responsible pathomechanism has not been elucidated yet. The assumption of an unspecific disturbance of lysosomal proenzyme targeting due to elevation of endosomal pH is opposed by the hypothesis of formation of a complex between tilorone and GAGs within the lysosomes, which renders GAGs indigestible to glycosidases. In cultures of bovine corneal fibroblasts the amounts of intracellular GAGs [dermatan sulphate (DS), heparan sulphate (HS) and chondroitin sulphate (CS)] were quantified. The fibroblasts were exposed to tilorone (5 microM), which was found to be readily taken up by the cells and to be accumulated within acidic compartments to finally achieve millimolar concentrations. Under these conditions the GAG storage is predominantly due to the accumulation of DS; however, the DS secretion into the culture medium was not affected. The HS accumulation was much less pronounced, accounting only for 3% of total GAG storage. Ammonium chloride (10 mM), which is known to diminish lysosomal enzyme activity by interfering with the mannose 6-phosphate receptor-mediated transport, prevents both HS and DS breakdown. By means of NMR spectroscopy it was shown that tilorone itself tends to display a concentration-dependent aggregation which was enhanced in the presence of GAGs. The diethylamino groups of tilorone interact physicochemically with DS, and to a smaller extent with HS, but not with chondroitin 4-sulphate. Thus, the strength of the interaction between tilorone and the different GAGs in vitro correlates with the potency of tilorone to inhibit the breakdown of the individual GAGs in cultured bovine fibroblasts. The results support the hypothesis of a specific interaction between tilorone and particular GAGs, rendering these resistant to enzymic degradation.


1985 ◽  
Vol 228 (2) ◽  
pp. 443-450 ◽  
Author(s):  
G Venn ◽  
R M Mason

The absence of keratan sulphate synthesis from skeletal tissues of young and mature mice and rats has been confirmed by (1) analysis of specific enzyme degradation products of newly synthesized glycosaminoglycans, and (2) immunohistochemistry and radioimmunoassay using a monoclonal antibody directed against keratan sulphate. Approx. 98% of the [35S]glycosaminoglycans synthesized in vivo by mouse and rat costal cartilage, and all of those of lumbar disc, are chondroitin sulphate. The remainder in costal cartilage were identified as heparan sulphate in mature rats. In contrast, [35S]glycosaminoglycans synthesized by cornea of both species comprised both chondroitin sulphate and keratan sulphate. In mice keratan sulphate accounted for 12-25% and in rats 40-50% of the total [35S]glycosaminoglycans, depending on the age of the animal. Experiments in vitro with organ culture of cartilage and cornea confirm these results. Absence of keratan sulphate from mouse costal cartilage and lumbar disc D1-proteoglycans was corroborated by inhibition radioimmunoassay with the monoclonal antibody MZ15 and by lack of staining for keratan sulphate in indirect immunofluorescence studies using the same antibody.


1991 ◽  
Vol 275 (2) ◽  
pp. 515-520 ◽  
Author(s):  
M Norman ◽  
G Ekman ◽  
U Ulmsten ◽  
K Barchan ◽  
A Malmström

Profound changes occur in the cervix during pregnancy. In particular, the connective tissue is remodelled. To elucidate the mechanisms behind this process, the metabolism of cervical connective tissue was studied using tissue cultures. Cervical biopsies from non-pregnant and pregnant women were incubated with [35S]sulphate. The proteoglycans of the tissue specimens were purified by ion-exchange and gel chromatography and characterized by SDS/PAGE and by enzymic degradation. In the non-pregnant cervix, the incorporation of [35S]sulphate into the proteoglycans was linear for 48 h. During the first 6 h of incubation the accumulation of chiefly one small labelled proteoglycan (apparent Mr 110,000) substituted with dermatan sulphate was recorded. This is in accordance with the known proteoglycan composition of non-pregnant cervical tissue. In addition, small amounts of two larger radioactive dermatan/chondroitin sulphate proteoglycans (apparent Mr values 220,000 and greater than 500,000) were recorded. After longer periods of incubation the proportion of heparan sulphate proteoglycans increased considerably. The pregnant tissue showed a clearly different composition of labelled proteoglycans. An increased accumulation of the two larger dermatan/chondroitin sulphate proteoglycans was seen in addition to the dominant small dermatan sulphate proteoglycan of the non-pregnant cervix. The rate of accumulation of these two proteoglycans was about 3 times higher in the pregnant tissue, whereas that of the small dermatan sulphate proteoglycan was only increased 2-fold. The fact that the concentration of proteoglycans in the pregnant cervix is approximately one-half of that in the non-pregnant cervix indicates that the turnover of proteoglycans in pregnant cervical tissue is significantly increased. The major effect of this profound change of metabolism was a 50% decrease in proteoglycan content and a 2-fold increased proportion of a dermatan sulphate proteoglycan with an apparent Mr of 220,000.


1980 ◽  
Vol 189 (3) ◽  
pp. 625-633 ◽  
Author(s):  
Gunilla Bengtsson ◽  
Thomas Olivecrona ◽  
Magnus Höök ◽  
Johan Riesenfeld ◽  
Ulf Lindahl

1. Lipoprotein lipase (EC 3.1.1.34), which was previously shown to bind to immobilized heparin, was now found to bind also to heparan sulphate and dermatan sulphate and to some extent to chondroitin sulphate. 2. The relative binding affinities were compared by determining (a) the concentration of NaCl required to release the enzyme from polysaccharide-substituted Sepharose; (b) the concentration of free polysaccharides required to displace the enzyme from immobilized polysaccharides; and (c) the total amounts of enzyme bound after saturation of immobilized polysaccharides. By each of these criteria heparin bound the enzyme most efficiently, followed by heparan sulphate and dermatan sulphate, which were more efficient than chondroitin sulphate. 3. Heparin fractions with high and low affinity for antithrombin, respectively, did not differ with regard to affinity for lipoprotein lipase. 4. Partially N-desulphated heparin (40–50% of N-unsubstituted glucosamine residues) was unable to displace lipoprotein lipase from immobilized heparin. This ability was restored by re-N-sulphation or by N-acetylation; the N-acetylated product was essentially devoid of anticoagulant activity. 5. Partial depolymerization of heparin led to a decrease in ability to displace lipoprotein lipase from heparin–Sepharose; however, even fragments of less than decasaccharide size showed definite enzyme-releasing activity. 6. Studies with hepatic lipase (purified from rat post-heparin plasma) gave results similar to those obtained with milk lipoprotein lipase. However, the interaction between the hepatic lipase and the glycosaminoglycans was weaker and was abolished at lower concentrations of NaCl. 7. The ability of the polysaccharides to release lipoprotein lipase to the circulating blood after intravenous injection into rats essentially conformed to their affinity for the enzyme as evaluated by the experiments in vitro.


1990 ◽  
Vol 266 (1) ◽  
pp. 15-24 ◽  
Author(s):  
Y Takeuchi ◽  
T Matsumoto ◽  
E Ogata ◽  
Y Shishiba

Proteoglycans in mineralized (0.5 M-EDTA/4 M-guanidinium chloride-extractable) and non-mineralized (4 M-guanidinium chloride-extractable) matrices synthesized by a mouse osteoblastic-cell line MC3T3-E1 were characterized at different phases of mineralization in vitro. Cell cultures were labelled with [35S]sulphate and either [3H]glucosamine or 3H-labelled amino acids. At the mineralization phase a large majority of proteoglycans were extracted with 4 M-guanidinium chloride (G extract), and at least five species of labelled proteoglycans were identified; dermatan sulphate proteoglycans (DSPG), apparent Mr approx. 120,000 and 70,000), heparan sulphate proteoglycans (HSPG, apparent Mr approx. 200,000 and 120,000) and DS chains with very little core protein. DSPGs weakly bound to an octyl-Sepharose CL-4B column and HSPGs bound more tightly, whereas DS chains did not bind to the column. Amounts of labelled proteoglycans extracted with 0.5 M-EDTA/4 M-guanidinium chloride (EDTA extract) were much less than those in G extract. Although the predominant species in the EDTA extract were comparable with the DS or DSPGs in the G extract, none of them bound to octyl-Sepharose CL-4B, indicating their lack of hydrophobicity. At the nonmineralizing phase a large chondroitin sulphate proteoglycan (Mr greater than 600,000) was found in the matrix in addition to the five proteoglycan species similar to those at the mineralization phase. Although DS chains at the early phase were similar in size to those at the mineralization phase, the ratio of 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulpho-D-galactose to 2-acetamido-2-deoxy-3-O-(beta-D-gluculo-4-enepyranosyluronic acid)-6-O-sulpho-D-galactose was less than that at the mineralization phase. These results agree with those of previous studies performed in vivo and suggest that alteration in the synthesis of proteoglycans is involved in the mineralization process. They also suggest that at the osteoblastic mineralization front proteoglycans undergo partial degradation and lose their hydrophobicity.


1994 ◽  
Vol 302 (1) ◽  
pp. 49-56 ◽  
Author(s):  
G J Thomas ◽  
M T Bayliss ◽  
K Harper ◽  
R M Mason ◽  
M Davies

Recent studies have shown that mesangial cells derived from human adult glomeruli synthesize a number of 35S-labelled proteoglycans including a large chondroitin sulphate proteoglycan (CSPG), two dermatan sulphate proteoglycans (biglycan and decorin) and two heparan sulphate proteoglycans [Thomas, Mason and Davies (1991) Biochem. J. 277, 81-88]. In the present study we have examined the interaction of these proteoglycans with hyaluronan (HA) using associative gel chromatography. Only the large CSPG bound to HA, with 60% of those molecules in the medium and 80% of those in the cell layer being able to interact. Reduction and alkylation, or treatment of the monomer CSPG with proteinases, prevented the formation of aggregates, suggesting that the core protein was involved. The aggregates formed between purified CSPG and HA could be dissociated in the presence of HA-oligosaccharides of at least 10 monosaccharides in length. The inclusion of link protein with CSPG and HA promoted the formation of aggregates. Experiments with 3H-labelled mesangial-cell proteoglycans confirmed that only the large CSPG, with core protein molecular masses of 400 kDa and 500 kDa, interacted with HA. After chondroitin ABC lyase treatment of CSPG isolated from conditioned culture medium, several bands similar to those observed with 3H-labelled core proteins were identified using a polyclonal antiserum that recognizes versican. A monoclonal antibody recognizing the 1-C-6 epitope in the G1 and G2 globular regions of aggrecan did not recognize either mesangial-cell CSPG or bovine aortic versican. Northern-blot analysis confirmed that human mesangial cells express versican. Thus human mesangial large CSPG is a member of the versican family of proteoglycans. The interaction of CSPG and HA within the glomerulus may be important in glomerular cell migration and proliferation.


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