scholarly journals Synthesis by Schwann cells of basal lamina and membrane-associated heparan sulfate proteoglycans.

1985 ◽  
Vol 101 (2) ◽  
pp. 660-666 ◽  
Author(s):  
H Mehta ◽  
C Orphe ◽  
M S Todd ◽  
C J Cornbrooks ◽  
D J Carey
Keyword(s):  
Heparan Sulfate ◽  
Chondroitin Sulfate ◽  
Schwann Cells ◽  
Basal Lamina ◽  
Guanidine Hydrochloride ◽  
Primary Cultures ◽  
Sensory Nerve ◽  
Low Carbohydrate ◽  
Schwann Cell Development ◽  
Triton X

Primary cultures that contain only Schwann cells and sensory nerve cells synthesize basal lamina. The assembly of this basal lamina appears to be essential for normal Schwann cell development. In this study, we demonstrate that Schwann cells synthesize two major heparan sulfate-containing proteoglycans. Both proteoglycans band in dissociative CsCl gradients at densities less than 1.4 g/ml, and therefore, presumably, have relatively low carbohydrate-to-protein ratios. The larger of these proteoglycans elutes from Sepharose CL-4B in 4 M guanidine hydrochloride (GuHCl) at a Kav of 0.21 and contains heparan sulfate and chondroitin sulfate chains of Mr 21,000 in a ratio of approximately 3:1. This proteoglycan is extracted from cultures by 4 M GuHCl but not Triton X-100 and accumulates only when Schwann cells are actively synthesizing basal lamina. The smaller proteoglycan elutes from Sepharose CL-4B at a Kav of 0.44 and contains heparan sulfate and chondroitin sulfate chains of Mr 18,000 in a ratio of approximately 4:1. This proteoglycan is extracted by 4 M GuHCl or by Triton X-100. The accumulation of this proteoglycan is independent of basal lamina production.

Effects of beta-xylosides on proteoglycan biosynthesis and morphology of PC12 pheochromocytoma cells and primary cultures of rat cerebellum

1991 ◽  
Vol 99 (2) ◽  
pp. 237-246
Author(s):  
R.K. Margolis ◽  
B. Goossen ◽  
H. Tekotte ◽  
L. Hilgenberg ◽  
R.U. Margolis
Keyword(s):  
Heparan Sulfate ◽  
Chondroitin Sulfate ◽  
Pc12 Cells ◽  
Primary Cultures ◽  
Fold Increase ◽  
Pheochromocytoma Cells ◽  
Rat Cerebellum ◽  
Explant Cultures ◽  
Collagen Substratum ◽  
Pc12 Pheochromocytoma Cells

We have examined the effects of beta-xylosides, which act as exogenous acceptors for glycosaminoglycan chain initiation, on the morphology and proteoglycan biosynthesis of PC12 pheochromocytoma cells, and on monolayer, aggregate and explant cultures of early postnatal rat cerebellum. PC12 cells cultured for 13 days in the presence of nerve growth factor (NGF) and beta-xyloside, and labeled during days 11–13 with sodium [35S]sulfate, showed an 8- to 11-fold increase in [35S]sulfate-labeled macromolecules released into the culture medium. Most of the increase was accounted for by chondroitin sulfate, which was in the form of free glycosaminoglycan chains, which were not acid-precipitable. The presence of beta-xyloside also led to a 65–115% increase in [35S]sulfate incorporation into cell-associated glycosaminoglycans and glycoproteins of untreated and NGF-treated PC12 cells, respectively. beta-Xyloside treatment reduced the size of the chondroitin sulfate chains in both the cells and medium from approximately 34,000 to 10,000 Mr, but had much less effect on heparan sulfate, which decreased in size from 16,000 to 13,000-14,500 Mr (in the medium and cells, respectively). beta-Xyloside inhibition of proteoglycan biosynthesis was accompanied by significant morphological effects in NGF-treated PC12 cells, consisting of an increase in length and decrease in the branching, diameter and adhesion to the collagen substratum of the PC12 cell processes. p-Nitrophenyl- and 4-methylumbelliferyl-beta-D-xylosides produced similar effects, which were not seen with p-nitrophenyl-beta-D-galactoside. beta-Xylosides also produced distinct alterations in the adhesion and morphology of monolayer, aggregate, and explant cultures of early postnatal rat cerebellum, which occurred together with inhibition of chondroitin sulfate proteoglycan biosynthesis and a decrease in glycosaminoglycan chain size. These studies indicate that chondroitin sulfate (and probably also heparan sulfate) proteoglycans play a significant role in modulating cell-cell and cell-matrix interactions in nervous tissue development and differentiation.

scholarly journals Detection of S-100b protein in Triton cytoskeletons: an immunocytochemical study on cultured Schwann cells.

1990 ◽  
Vol 38 (11) ◽  
pp. 1583-1589 ◽  
Author(s):  
M G Rambotti ◽  
A Spreca ◽  
P Leoncini ◽  
M Estenoz ◽  
E Costantino-Ceccarini ◽  
...  
Keyword(s):  
Schwann Cells ◽  
Peripheral Nerves ◽  
Immune Reaction ◽  
Primary Cultures ◽  
Immunocytochemical Study ◽  
Resistant Material ◽  
Cultured Schwann Cells ◽  
Triton X ◽  
Short Time ◽  
In Cells

We investigated the subcellular distribution of S-100b protein in primary cultures of Schwann cells. The subcellular localization of the protein in cells fixed and then permeabilized is similar, if not identical, to that seen in Schwann cells in peripheral nerves, i.e., S-100b protein is found in the cytoplasm and associated with membranes and filamentous structures. In cells either fixed in the presence of Triton X-100 or exposed to Triton X-100 for a short time before fixation (Triton cytoskeletons), the immune reaction product is considerably less intense, and the protein is associated with filaments running parallel to the long axis of the cell as well as in a submembranous position. Including CaCl2 in the buffer during fixation in the presence of Triton X-100 does not result in any increase in the intensity of the immune reaction product in Triton cytoskeletons, suggesting that, within the limits of the technique employed, no binding of additional S-100b protein to the Triton X-100-resistant material can be induced. On the other hand, including EGTA results in a substantial decrease in the intensity of the immune reaction product in Triton cytoskeletons. Altogether, these findings suggest that a remarkable fraction of S-100b protein in cultured Schwann cells is associated with elements of the cytoskeleton and that Ca2+ exerts some regulatory role in the association of S-100b protein with the cytoskeleton.

Proteoglycan involvement during development of lesional pulmonary edema

1998 ◽  
Vol 274 (2) ◽  
pp. L203-L211 ◽  
Author(s):  
Daniela Negrini ◽  
Alberto Passi ◽  
Giancarlo De Luca ◽  
Giuseppe Miserocchi
Keyword(s):  
Heparan Sulfate ◽  
Chondroitin Sulfate ◽  
Solid Phase ◽  
Guanidine Hydrochloride ◽  
Membrane Integrity ◽  
Weight Ratio ◽  
Chondroitin Sulfate Proteoglycans ◽  
Initial Increase ◽  
Parietal Pleura ◽  
Tissue Compliance

We evaluated the effect of pancreatic elastase (7 IU iv) on pulmonary interstitial pressure (Pip) in in situ rabbit lungs by a micropuncture technique through the intact parietal pleura. Pip was −10.8 ± 2.2 (SD) cmH2O in the control condition, increased to +5.1 ± 1.7 cmH2O at ∼60 min [condition referred to as mild edema (ME)], and subsequently decreased to −0.15 ± 0.8 cmH2O, remaining steady from 80 up to 200 min with a marked increase in lung wet-to-dry weight ratio [condition referred to as severe edema (SE)], suggesting an increase in tissue compliance. We functionally correlated the measured Pip to structural modifications of proteoglycans, the major interfibrillar component of the extracellular matrix (ECM). The strength of the noncovalent bonds linking proteoglycans to other ECM components decreased with increasing severity of edema, as indicated by the increased extractability of proteoglycans with guanidine hydrochloride. Total proteoglycan recovery (expressed as μg hexuronate/g dry tissue) increased from 436.8 ± 14 in the control condition to 495.3 ± 23 and 547.0 ± 10 in ME and SE, respectively. Gel-filtration chromatography showed in ME a fragmentation of heparan sulfate proteoglycans, suggesting that elastase treatment first affected basement membrane integrity, whereas large chondroitin sulfate proteoglycans were degraded only in SE. Elastase caused a fragmentation only of the core protein of proteoglycans, the binding properties of which to collagens, fibronectin, and hyaluronic acid were markedly decreased, as indicated by a solid-phase binding assay. The sequential degradation of heparan sulfate and chondroitin sulfate proteoglycans may account for the initial increase in microvascular permeability, followed by a loss of the native architecture of the ECM, which may be responsible for the increase in tissue compliance.

scholarly journals Interleukin-4 Regulates the Expression of CD209 and Subsequent Uptake of Mycobacterium leprae by Schwann Cells in Human Leprosy

2010 ◽  
Vol 78 (11) ◽  
pp. 4634-4643 ◽  
Author(s):  
Rosane M. B. Teles ◽  
Stephan R. Krutzik ◽  
Maria T. Ochoa ◽  
Rosane B. Oliveira ◽  
Euzenir N. Sarno ◽  
...  
Keyword(s):  
Schwann Cell ◽  
Peripheral Nerve ◽  
Schwann Cells ◽  
Primary Cultures ◽  
Mycobacterium Leprae ◽  
Microbial Pathogens ◽  
Interleukin 4 ◽  
Common Mechanism ◽  
Specific Cell

ABSTRACT The ability of microbial pathogens to target specific cell types is a key aspect of the pathogenesis of infectious disease. Mycobacterium leprae, by infecting Schwann cells, contributes to nerve injury in patients with leprosy. Here, we investigated mechanisms of host-pathogen interaction in the peripheral nerve lesions of leprosy. We found that the expression of the C-type lectin, CD209, known to be expressed on tissue macrophages and to mediate the uptake of M. leprae, was present on Schwann cells, colocalizing with the Schwann cell marker, CNPase (2′,3′-cyclic nucleotide 3′-phosphodiesterase), along with the M. leprae antigen PGL-1 in the peripheral nerve biopsy specimens. In vitro, human CD209-positive Schwann cells, both from primary cultures and a long-term line, have a higher binding of M. leprae compared to CD209-negative Schwann cells. Interleukin-4, known to be expressed in skin lesions from multibacillary patients, increased CD209 expression on human Schwann cells and subsequent Schwann cell binding to M. leprae, whereas Th1 cytokines did not induce CD209 expression on these cells. Therefore, the regulated expression of CD209 represents a common mechanism by which Schwann cells and macrophages bind and take up M. leprae, contributing to the pathogenesis of leprosy.

scholarly journals Globular and asymmetric acetylcholinesterase in frog muscle basal lamina sheaths.

1986 ◽  
Vol 102 (3) ◽  
pp. 762-768 ◽  
Author(s):  
M Nicolet ◽  
M Pinçon-Raymond ◽  
F Rieger
Keyword(s):  
Basal Lamina ◽  
Acetylcholine Receptors ◽  
Muscle Fibers ◽  
Frog Muscle ◽  
Motor Endplate ◽  
Molecular Forms ◽  
Nonionic Detergent ◽  
Plasmic Membrane ◽  
Triton X

After denervation in vivo, the frog cutaneus pectoris muscle can be led to degenerate by sectioning the muscle fibers on both sides of the region rich in motor endplate, leaving, 2 wk later, a muscle bridge containing the basal lamina (BL) sheaths of the muscle fibers (28). This preparation still contains various tissue remnants and some acetylcholine receptor-containing membranes. A further mild extraction by Triton X-100, a nonionic detergent, gives a pure BL sheath preparation, devoid of acetylcholine receptors. At the electron microscope level, this latter preparation is essentially composed of the muscle BL with no attached plasmic membrane and cellular component originating from Schwann cells or macrophages. Acetylcholinesterase is still present in high amounts in this BL sheath preparation. In both preparations, five major molecular forms (18, 14, 11, 6, and 3.5 S) can be identified that have either an asymmetric or a globular character. Their relative amount is found to be very similar in the BL and in the motor endplate-rich region of control muscle. Thus, observations show that all acetylcholinesterase forms can be accumulated in frog muscle BL.

Abnormal expression of heparan sulfate proteoglycan on basal lamina of muscle fibers in two Japanese patients with adhalin deficiency

1995 ◽  
Vol 5 (6) ◽  
pp. 467-474 ◽  
Author(s):  
Itsuro Higuchi ◽  
Hidetoshi Fukunaga ◽  
Kiichiro Matsumura ◽  
Masaru Inose ◽  
Kotaro Izumi ◽  
...  
Keyword(s):  
Heparan Sulfate ◽  
Basal Lamina ◽  
Muscle Fibers ◽  
Japanese Patients ◽  
Heparan Sulfate Proteoglycan ◽  
Sulfate Proteoglycan ◽  
Abnormal Expression

scholarly journals Glucose stimulates transcription of fatty acid synthase and malic enzyme in avian hepatocytes

1998 ◽  
Vol 274 (3) ◽  
pp. E493-E501 ◽  
Author(s):  
F. Bradley Hillgartner ◽  
Tina Charron
Keyword(s):  
Fatty Acid ◽  
High Fat Diet ◽  
Malic Enzyme ◽  
Fatty Acid Synthase ◽  
Primary Cultures ◽  
Pentose Phosphate ◽  
Mrna Abundance ◽  
Low Fat Diet ◽  
Low Carbohydrate

Transcription of fatty acid synthase (FAS) and malic enzyme (ME) in avian liver is low during starvation or feeding a low-carbohydrate, high-fat diet and high during feeding a high-carbohydrate, low-fat diet. The role of glucose in the nutritional control of FAS and ME was investigated by determining the effects of this metabolic fuel on expression of FAS and ME in primary cultures of chick embryo hepatocytes. In the presence of triiodothyronine, glucose (25 mM) stimulated an increase in the activity and mRNA abundance of FAS and ME. These effects required the phosphorylation of glucose to glucose 6-phosphate but not further metabolism downstream of the aldolase step of the glycolytic pathway. Xylitol mimicked the effects of glucose on FAS and ME expression, suggesting that an intermediate of the pentose phosphate pathway may be involved in mediating this response. The effects of glucose on the mRNA abundance of FAS and ME were accompanied by similar changes in transcription of FAS and ME. These data support the hypothesis that glucose plays a role in mediating the effects of nutritional manipulation on transcription of FAS and ME in liver.

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