scholarly journals Brain peptides and glial growth. II. Identification of cells that secrete glia-promoting factors.

1986 ◽  
Vol 102 (3) ◽  
pp. 812-820 ◽  
Author(s):  
D Giulian ◽  
D G Young

Glia-promoting factors (GPFs) are brain peptides which stimulate growth of specific macroglial populations in vitro. To identify the cellular sources of GPFs, we examined enriched brain cell cultures and cell lines derived from the nervous system for the production of growth factors. Ameboid microglia secreted astroglia-stimulating peptides, while growing neurons were the best source of the oligodendroglia-stimulating factors. These secretion products co-purified by gel filtration, anion exchange chromatography, and reverse-phase high performance liquid chromatography with GPFs isolated from goldfish and rat brain. Our findings suggest that glial growth in the central nervous system is regulated in part by a signaled release of peptides from specific secretory cells.

2007 ◽  
Vol 85 (1) ◽  
pp. 88-95 ◽  
Author(s):  
Amandeep Kaur ◽  
Sukhdev Singh Kamboj ◽  
Jatinder Singh ◽  
Rajinder Singh ◽  
Melissa Abrahams ◽  
...  

Three monomeric monocot lectins from Zephyranthes carinata, Zephyranthes candida, and Gloriosa superba with carbohydrate specificity towards mannose derivatives and (or) oligomannose have been isolated and purified from their storage tissues. The lectins were purified by anion-exchange chromatography on DEAE–Sephacyl and by gel filtration chromatography on Biogel P-200 followed by high-performance liquid chromatography. The purified lectins, Z. carinata, Z. candida, and G. superba had molecular masses of 12, 11.5, and 12.5 kDa, respectively, as determined by gel filtration and SDS–PAGE, indicating that they are monomers. In a hapten inhibition assay, methyl-α-d-mannopyranoside inhibited agglutination of both Z. candida and Z. carinata; the latter was also inhibited by Man(α1-2)Man and Man(α1-3)Man. Gloriosa superba showed inhibition only with Man(α1-4)Man of all of the sugars and glycoproteins tested. All purified lectins agglutinated red blood cells from rabbit, whereas G. superba was also reactive towards erythrocytes from guinea pig. All of the lectins were nonglycosylated and did not require metal ions for their activity. They were labile above 60 °C and were affected by denaturing agents such as urea, thiourea, and guanidine–HCl. The lectins were virtually nonmitogenic, like other members of Amaryllidaceae and Liliaceae. Of the 3 lectins, G. superba was found to be highly toxic to the BSC-1 cell line (African green monkey kidney epithelial cells), while both of the Zephyranthes species showed significant in vitro inhibition of poxvirus replication in BSC-1 cells without any toxic effects to the cells. In addition, Z. candida also exhibited significant anticancer activity against SNB-78, a CNS human cancer cell line.


Plant Disease ◽  
2003 ◽  
Vol 87 (3) ◽  
pp. 233-240 ◽  
Author(s):  
Edson L. Z. Figueira ◽  
Alejandro Blanco-Labra ◽  
Antônio Carlos Gerage ◽  
Elisabete Y. S. Ono ◽  
Elizabeth Mendiola-Olaya ◽  
...  

A screening for specific amylase inhibitor levels against amylase from Fusarium verticillioides (Fusarium moniliforme), the most relevant mycotoxigenic fungus in corn, was conducted on 37 corn hybrids. The amylase inhibitor levels in these hybrids ranged from 5.5 to 16.0 amylase inhibitor units per gram of corn (AIU/g) in the MASTER and AG5011 hybrids, respectively. The hybrid with the maximum content of inhibitor was used as the source of this new protein. The inhibitor was partially purified using fractional precipitation, gel filtration on Sephadex G-75 column, high performance liquid chromatography (HPLC) Superose HR 10/30 column, and HPLC anion exchange chromatography, obtaining a 20.7-fold purification. Electrophoresis after denaturing and heating under reductive conditions showed an apparent 23.8 kDa molecular mass and an acidic isoelectric point of 5.4, which differs from previous molecular masses reported for other inhibitors present in corn seeds (14 and 22 kDa). This inhibitor showed activity against amylases from human saliva and pancreas, from the fungi F. verticillioides and Aspergillus flavus, and from the insects Acanthoscelides obtectus, Zabrotes subfasciatus, Tribolium castaneum, and Sitotroga cerealella. The mycoflora found in the corn grain indicated Fusarium sp. as the most prevalent fungi (81.1% of the samples), with a count ranging from 1.5 × 102 to 2.4 × 106 CFU/g of corn. The presence of fumonisins was detected in 21 out of the 37 hybrids studied, ranging from 0.05 to 2.67 μg of FB per gram of corn. No correlation could be established between this amylase inhibitor level in the corn seeds and the presence of Fusarium sp. or with the fumonisin content under the experimental conditions of the test.


1987 ◽  
Vol 114 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Chohei Shigeno ◽  
Itsuo Yamamoto ◽  
Shegiharu Dokoh ◽  
Megumu Hino ◽  
Jun Aoki ◽  
...  

Abstract. We have partially purified a tumour factor capable of stimulating both bone resorption in vitro and cAMP accumulation in osteoblastic ROS 17/2 cells from three human tumours associated with humoral hypercalcaemia of malignancy. Purification of tumour factor by sequential acid urea extraction, gel filtration and cation-exchange chromatography, reverse-phase high performance liquid chromatography followed by analytical isoelectric focussing provided a basic protein (pI > 9.3) with a molecular weight of approximately 13 000 as a major component of the final preparation which retained both the two bioactivities. Bone resorbing activity and cAMP-increasing activity in purified factor correlated with each other. cAMP-increasing activity of the factor was heat- and acid-stable, but sensitive to alkaline ambient pH. Treatment with trypsin destroyed cAMP-increasing activity of the factor. Synthetic parathyroid hormone (PTH) antagonist, human PTH-(3– 34) completely inhibited the cAMP-increasing activity of the factor. The results suggest that this protein factor, having its effects on both osteoclastic and osteoblastic functions, may be involved in development of enhanced bone resorption in some patients with humoral hypercalcaemia of malignancy.


1986 ◽  
Vol 164 (2) ◽  
pp. 594-604 ◽  
Author(s):  
D Giulian ◽  
T J Baker ◽  
L C Shih ◽  
L B Lachman

By screening specific populations of rat brain cells, we found that ameboid microglia secrete an 18 kD peptide with IL-1 biological activity. The IL-1 activity released by microglia was found to be identical to rat macrophage IL-1 on fractionation by gel filtration and high pressure liquid anion-exchange chromatography, and it was neutralized by an antiserum specific for murine IL-1. When added to astroglia grown in culture, microglial IL-1 increased the cell number of five- to sevenfold, and increased astroglial incorporation of [3H]thymidine by three- to fivefold. We propose that the proliferation of astroglia in specific brain regions may be regulated by the signaled release of IL-1 from activated microglial cells.


1993 ◽  
Vol 291 (3) ◽  
pp. 713-721 ◽  
Author(s):  
M Odenthal-Schnittler ◽  
S Tomavo ◽  
D Becker ◽  
J F Dubremetz ◽  
R T Schwarz

In this paper we report experiments demonstrating the presence of N-linked oligosaccharide structures in Toxoplasma gondii tachyzoites, providing the first direct biochemical evidence that this sporozoan parasite is capable of synthesizing N-linked glycans. The tachyzoite surface glycoprotein gp23 was metabolically labelled with [3H]glucosamine and [3H]mannose. Gel-filtration chromatography on Bio-Gel P4 columns produced four radiolabelled N-linked glycopeptides which were sensitive to peptidase-N-glycanase F, but resistant to endoglycosidases H and F. Using chemical analysis and exoglycosidase digestions followed by Dionex-high-pH anion-exchange chromatography and size fractionation on Bio-Gel P4 we show that gp23 has N-linked glycans in the hybrid- or complex-type structure composed of N-acetylgalactosamine, N-acetylglucosamine and mannose and devoid of sialic acid and fucose residues. In addition, the sensitivity of glycopeptides from glycoprotein extracts to endoglycosidases H and F revealed the in vivo synthesis of oligomannose-type structures by T. gondii tachyzoites. We have extended these findings by demonstrating the ability of T. gondii microsomes to synthesize in vitro a glucosylated lipid-bound high-mannose structure (Glc3Man9GlcNAc2) that is assumed to be identical with the common precursor for N-glycosylation in eukaryotes.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Jian Sun ◽  
Tzi-Bun Ng ◽  
Hexiang Wang ◽  
Guoqing Zhang

Little was known about bioactive compounds from the hallucinogenic mushroomBoletus speciosus. In the present study, a hemagglutinin (BSH,B. speciosushemagglutinin) was isolated from its fruiting bodies and enzymatic properties were also tested. The chromatographic procedure utilized comprised anion exchange chromatography on Q-Sepharose, cation exchange chromatography on CM-Cellulose, cation exchange chromatography on SP-Sepharose, and gel filtration by FPLC on Superdex 75. The hemagglutinin was a homodimer which was estimated to be approximately 31 kDa in size. The activity of BSH was stable up to 60°C, while there was a precipitous drop in activity when the temperature was elevated to 70°C. BSH retained 25% hemagglutinating activity when exposed to 100 mM NaOH and 25 mM HCl. The activity was potently inhibited by 1.25 mM Hg2+and slightly inhibited by Fe2+, Ca2+, and Pb2+. None of the sugars tested showed inhibition towards BSH. Its hemagglutinating activity towards human erythrocytes type A, type B, and type AB was higher than type O. The hemagglutinin showed antiproliferative activity towards hepatoma Hep G2 cells and mouse lymphocytic leukemia cells (L1210)in vitro, with IC50of 4.7 μM and 7.0 μM, respectively. It also exhibited HIV-1 reverse transcriptase inhibitory activity with an IC50of 7.1 μM.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Pai-Feng Kao ◽  
Shwu-Huey Wang ◽  
Wei-Ting Hung ◽  
Yu-Han Liao ◽  
Chun-Mao Lin ◽  
...  

The major cell wall constituent ofGanoderma lucidum(G. lucidum) isβ-1,3-glucan. This study examined the polysaccharide from the residues of alkaline-extracted fruiting bodies using high-performance anion-exchange chromatography (HPAEC), and it employed nuclear magnetic resonance (NMR) and mass spectrometry (MS) to confirm the structures. We have successfully isolated low-molecular-weightβ-1,3-glucan (LMG), in high yields, from the waste residue of extracted fruiting bodies ofG. lucidum. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay evaluated the capability of LMG to suppress H2O2-induced cell death in RAW264.7 cells, identifying that LMG protected cells from H2O2-induced damage. LMG treatment decreased H2O2-induced intracellular reactive oxygen species (ROS) production. LMG also influenced sphingomyelinase (SMase) activity, stimulated by cell death to induce ceramide formation, and then increase cell ROS production. Estimation of the activities of neutral and acid SMasesin vitroshowed that LMG suppressed the activities of both neutral and acid SMases in a concentration-dependent manner. These results suggest that LMG, a water-solubleβ-1,3-glucan recycled from extracted residue ofG. lucidum, possesses antioxidant capability against H2O2-induced cell death by attenuating intracellular ROS and inhibiting SMase activity.


1986 ◽  
Vol 102 (3) ◽  
pp. 803-811 ◽  
Author(s):  
D Giulian ◽  
R L Allen ◽  
T J Baker ◽  
Y Tomozawa

Glia-promoting factors (GPFs) are peptides of the central nervous system which accelerate the growth of specific glial populations in vitro. Although these factors were first discovered in the goldfish visual system (Giulian, D., Y. Tomozawa, H. Hindman, and R. Allen, 1985, Proc. Natl. Acad. Sci. USA., 83:4287-4290), we now report similar peptides are found in mammalian brain. The cerebral cortex of rat contains oligodendroglia-stimulating peptides, GPF1 (15 kD) and GPF3 (6 kD), as well as astroglia-stimulating peptides, GPF2 (9 kD) and GPF4 (3 kD). The concentrations of specific GPFs increase in brain during periods of gliogenesis. For example, GPF1 and GPF3 are found in postnatal rat brain during a peak of oligondendroglial growth while GPF2 and GPF4 are first detected at a time of astroglial proliferation in the embryo. Stab wound injury to the cerebral cortices of rats stimulates astroglial proliferation and induces marked elevations in levels of GPF2 and GPF4. Our findings suggest that two distinct classes of GPFs, those acting upon oligodendroglia and those acting upon astroglia, help to regulate cell growth in the developing and injured central nervous system.


1999 ◽  
Vol 19 (3) ◽  
pp. 219-225 ◽  
Author(s):  
Hasi Das ◽  
Vani Jayaraman ◽  
Indranil Bhattacharya

Composition analysis of monosaccharides of Sepharose 4B purified NC 92 LPS and the polysaccharides fractions from Sephadex G-50 chromatography was performed by high performance anion exchange chromatography using pulsed amperometric detection. Rhamnose, mannose, galactose and glucose are present in a substantial amount in the purified LPS (Pk I). High molecular weight purified polysaccharides (PS I) obtained after sephadex gel filtration of the purified LPS (Pk I) acid hydrolysate showed an increase in glucose:galactose ratio. This indicates the presence of the peanut root lectin (PRA II) specific sugar in higher proportion on the O-antigen part of the LPS molecule, which may aid in the critical recognition reaction.


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