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Ito J, Kato T, Yamakawa Y, Kato H, Sakazaki Y, Lim R, Tanaka R. Interaction of glia maturation factor with the glial cell membrane. Brain Res 1982; 243:309-14. [PMID: 7104741 DOI: 10.1016/0006-8993(82)90254-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Glia maturation factor (GMF) immobilized on agarose beads retained the same mitogenic and morphological transforming activities as free GMF when tested on glioblasts. The exposure of glioblasts to immobilized GMF for 5 min provoked the initiation of DNA synthesis and maximal stimulation was obtained within 30 min. Thiol-reducing agents, such as dithiothreitol and cysteine, increased the biological activity of GMF. These data suggest the presence of a surface receptor to GMF on the glioblasts, while the reduction of the thiol group(s) in GMF promotes the binding to its receptor. Repeated use of immobilized GMF decreased both the mitogenic and the morphological transforming activities. Immobilized GMF used for the third time lost its biological activity. This implies the existence of a certain kind of degradation system such as a proteolytic enzyme located close to the GMF receptor on the glial cell surface.
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277
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Turriff DE, Lim R. Temperature dependence of morphological response of glioblasts to glia maturation factor. Dev Neurosci 1982; 5:205-7. [PMID: 7128483 DOI: 10.1159/000112677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Glioblasts respond to glia maturation factor (GMF) by outgrowth of cell processes. This morphological response takes place at 37 degrees C but not at 23 degrees C, suggesting the involvement of temperature-dependent chemical processes in the mechanism of action of GMF. The morphological response of glioblasts to GMF is correlated with the rearrangement of microtubules but not with any net change in tubulin content of the cells.
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278
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Lim R, Troy SS, Turriff DE, Prunskis JV. Enucleation blocks the morphological response of glioblasts to glia maturation factor. Dev Neurosci 1982; 5:308-13. [PMID: 6291892 DOI: 10.1159/000112690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Culture glioblasts obtained from rat fetuses were enucleated with cytochalasin B. The glia maturation factor stimulated the morphological differentiation of nucleated but not enucleated cells. In contrast, 8-bromo-cyclic AMP stimulated the morphological differentiation of both nucleated and enucleated cells. This distinction implies a difference in the mode of action of the two agents on cultured glioblasts, and suggests that an interaction between the nucleus and cytoplasm is required for expression of the morphological effect of the glia maturation factor.
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279
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Lim R, Nakagawa S, Arnason BG, Turriff DE. Glia maturation factor promotes contact inhibition in cancer cells. Proc Natl Acad Sci U S A 1981; 78:4373-7. [PMID: 6945589 PMCID: PMC319792 DOI: 10.1073/pnas.78.7.4373] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The effect of bovine glia maturation factor on the growth pattern of cancer cells was investigated in the rat glioma cell line 354A. When the cells were grown in the serum-free defined medium N2 in the absence of the factor, the cells proliferated with a doubling time of 24 hr without showing contact inhibition. After reaching confluency, the cell layer formed numerous foci from which heaps of cell colonies arose. The addition of glia maturation factor to the culture stimulated cell division in the logarithmic phase but prevented overgrowth once the cells arrived at confluency. The ability of glia maturation factor to restore contact inhibition suggests a regulatory role in normal and neoplastic cells.
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280
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Kato T, Fukui Y, Turriff DE, Nakagawa S, Lim R, Arnason BG, Tanaka R. Glia maturation factor in bovine brain: partial purification and physicochemical characterization. Brain Res 1981; 212:393-402. [PMID: 7225875 DOI: 10.1016/0006-8993(81)90471-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Glia maturation factor (GMF) is partially purified from bovine brains by the following procedure: extraction at physiologic pH, dialysis and freeze-drying of the extract, ethanol washing of the dried powder and re-extraction of the ethanol-washed residue with Tris-buffered saline, ion-exchange chromatography with DEAE Sephadex and molecular sieving with Bio-gel P-200. The partially purified protein has an apparent molecular weight of 23,000 and an isoelectric point of 4.75, and retains both morphological transforming and mitogenic activities when tested on glioblasts. Both activities are susceptible to protease digestion and heat inactivation. The procedure results in a 400-fold purification of the morphological activity and a 1400-fold purification of the mitogenic activity. Both activities are detectable when GMF is used in nanogram quantities. The possibility that both functions are expressions of the same factor and the possible role of GMF in the differential or sequential stimulation of cell growth and maturation are discussed.
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281
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Kato T, Yamakawa Y, Lim R, Turriff DE, Tanaka R. Biological effects of bovine glia maturation factor on glial cells in culture. Neurochem Res 1981; 6:401-12. [PMID: 7266748 DOI: 10.1007/bf00963855] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Optimal bioassay conditions for bovine glia maturation factor (GMF) were determined among glial cells from normal glioblasts to glioma cells. Rat glioblasts 4-8 days after subculture show the highest response t GMF with regard to morphological transformation and mitogenic activity. Bovine GMF enhances DNA synthesis of rat glioblasts at 12 h after stimulation; maximum incorporation of [methyl-3H]thymidine was detected at 18 h. GMF increases twofold the saturation density of rat glioblasts but does not alter that of C6 astrocytoma cells. The apparent inhibition of mitogenic activity of high doses of GMF is seen in both normal and malignant glial cells.
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282
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Lim R, Cheung ST, Crayton JW. alpha-L-Aspartyl-L-alanine (a neural dipeptide) enhances synaptic transmission. EXPERIENTIA 1981; 37:158-60. [PMID: 6263669 DOI: 10.1007/bf01963206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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283
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Turriff DE, Lim R. Distribution of glia maturation factor-like activity in organs and cells. Dev Neurosci 1981; 4:110-7. [PMID: 7227225 DOI: 10.1159/000112746] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Glia maturation factor (GMF) is a protein first isolated from the adult pig brain. GMF-like activity can be demonstrated in rat organs, including brain, kidney and heart. The activity in these organs is low in newborn animals, but increases with development, reaching the adult level in 1 or 2 weeks. GMF-like activities in the various organs are similar in physicochemical properties, being heat-labile, susceptible to proteolytic enzymes, and are associated with an acidic molecule of large size. Cultured rat glioblasts and C6 glioma cells, but not their conditioned media, contain large amounts of endogenous GMF-like activity. GMF obtained from brains and cultured glial cells also possess mitogenic action. Subcellular fractionation localizes GMF-like activity in the cytosol and in microsomal and nerve ending fractions. GMF-like activity is also detectable in bovine, sheep, monkey and human brains. The results suggest that GMF is ubiquitous in distribution, and at least a portion of it may be associated with the structural components of the cells.
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284
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Cheung ST, McIlhany MP, Lim R, Mullan S. Preliminary characterization of vasocontractile activities in erythrocytes. J Neurosurg 1980; 53:37-43. [PMID: 7411207 DOI: 10.3171/jns.1980.53.1.0037] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The vasocontractile activities of washed red cell preparations hemolyzed by various methods were studied in vitro using isolated canine basilar arteries. Significant contractions were induced by each preparation. The maximum strength of contraction attained by the various preparations was similar. The contractile activity appeared to be dose-related, and molecular exclusion chromatography demonstrated that the activity migrated with the fraction of approximately 40,000 to 45,000 molecular weight. The vasocontractile effect of the active fraction was sustained in vitro when tested against basilar artery, but was inactive in peripheral arterial preparations. Preliminary biochemical characterization indicates that the contractile activity resides in a protein. Enzymatic digestion of the crude fraction appears to enhance the contractile activity significantly, and this observation suggests a possible mechanism for the delayed onset of ischemic symptoms encountered in the clinical situation.
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285
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Cheung ST, Lim R. Isolation of gamma-glutamylaspartic acid and alpha-aspartylalanine from pig brain. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 586:418-24. [PMID: 476146 DOI: 10.1016/0304-4165(79)90110-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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286
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Kato T, Chiu TC, Lim R, Troy SS, Turriff DE. Multiple molecular forms of glia maturation factor. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 579:216-27. [PMID: 465531 DOI: 10.1016/0005-2795(79)90100-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Glia maturation factor from the pig brain can be detected in two molecular forms: the high molecular weight form which is 200 000 dalton in size and the low molecular weight form which is 40 000 dalton in size, as determined by Sephadex gel filtration. The former accounts for 85% of the total biological activity extracted at physiologic pH. The proportion of the low molecular weight form increases following freeze-thawing and ion-exchange chromatography. In addition to the morphological effects, both forms possess mitogenic activity but no esteropeptidase activity. Both forms show similar enzyme susceptibility, being inactivated by papain, ficin and pronase but resistant to subtilisin, thermolysin and trypsin. The high molecular weight form is more resistant to denaturation by low pH, heating and urea than the low molecular weight form. The high molecular weight factor has an isoelectric point of 4.27 whereas the low molecular weight factor has one of 5.04.
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287
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Glisson SN, El-Etr AA, Lim R. Prolongation of pancuronium-induced neuromuscular blockade by intravenous infusion of nitroglycerin. Anesthesiology 1979; 51:47-9. [PMID: 110176 DOI: 10.1097/00000542-197907000-00010] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Based upon clinical observation of undue prolongation of pancuronium-induced blockade in the presence of intravenous infusion of nitroglycerin, neuromuscular blockades produced by pancuronium, succinylcholine and d-tubocurarine were studied in 51 cats using the sciatic-gastrocnemius nerve-muscle preparation. Pancuronium-induced blockade was found to be significantly prolonged (P less than 0.1) in the presence of a nitroglycerin infusion of 1 microgram/kg/min (65 vs. 127 min). Less, but still significant, prolongation occurred when nitroglycerin, 0.5 microgram/kg/min, was infused. The intravenous infusion of nitroglycerin must be started prior to the pancuronium injection for the block to be prolonged. Neuromuscular blocks produced by succinylcholine and d-tubocurarine were not altered by nitroglycerin. In experiments using the isolated rat diaphragm preparation, the depth of pancuronium-induced block was found not to be changed by nitroglycerin, suggesting an effect of nitroglycerin on the process of recovery from blockade. These findings indicate a selective pancuronium-nitroglycerin interaction.
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288
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289
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Lim R, Troy SS, Turriff DE. Fine structure of cultured glioblasts before and after stimulation by a glia maturation factor. Exp Cell Res 1977; 106:357-72. [PMID: 558886 DOI: 10.1016/0014-4827(77)90181-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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290
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Lim R, Turriff DE, Troy SS, Moore BW, Eng LF. Glia maturation factor: effect on chemical differentiation of glioblasts in culture. Science 1977; 195:195-6. [PMID: 188136 DOI: 10.1126/science.188136] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A protein factor from the adult brain increases the concentrations of adenosine 3',5'-monophosphate and S-100 protein in glioblasts in culture. Such changes are correlated with the outgrowth of cell processes.
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291
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Lim R, Turriff DE, Troy SS. Response of glioblasts to a morphological transforming factor: cinematographic and chemical correlations. Brain Res 1976; 113:165-70. [PMID: 182320 DOI: 10.1016/0006-8993(76)90014-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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292
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Lim R, Mitsunobu K. Partial purification of a morphological transforming factor from pig brain. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 400:200-7. [PMID: 1164504 DOI: 10.1016/0005-2795(75)90175-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A protein that changes one type of embryonic rat brain cell in culture from a primitive morphology to one resembling mature glial cell has been purified 400-fold from pig brain. The procedure includes differential centrifugation, ethanol treatment, trypsin digestion and column chromatography with Sephadex G-200 and Sepharose 4B. Although not completely homogeneous, the protein is biologically active at a concentration of 1-10(-8) M. It has a molecular weight of 350 000 and is heat labile. It is inactivated by the extremes of pH and by 8 M urea. The isoionic point is lower than neutrality. The activity is resistant to DNAase, RNAase, periodate and trypsin, but is susceptible to pronase digestion.
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293
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Lim R, Mullan S. Enhancement of resistance of glial cells by dimethyl sulfoxide against sonic disruption. Ann N Y Acad Sci 1975; 243:358-61. [PMID: 1055553 DOI: 10.1111/j.1749-6632.1975.tb25376.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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294
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Abstract
One type of elmbryonic rat brain cell having an epithelioid morphology in the monolayer culture can be transformed by brain extract into cells having extensive processes resembling mature astrocytes. The transforming factor is a protein with a molecular weight of 350,000. A partially purified sample showed that it is active at a concentration as low as 1 x 10(-8)M. The transforming actvity is high in adult brains but low in embryonic brains and tumors of the nervous systems.
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295
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Lim R, Goedken MP. A partially purified membrane protein specific to the brain. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 322:359-71. [PMID: 4358087 DOI: 10.1016/0005-2795(73)90311-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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296
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Lim R, Mitsunobu K, Li W. Maturation-stimulating effect of brain extract and dibutyryl cyclic AMP on dissociated embryonic brain cells in culture. Exp Cell Res 1973. [DOI: 10.1016/0014-4827(73)90512-0] [Citation(s) in RCA: 188] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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297
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Lim R, Mitsunobu K, Li WK. Maturation-stimulation effect of brain extract and dibutyryl cyclic AMP on dissociated embryonic brain cells in culture. Exp Cell Res 1973; 79:243-6. [PMID: 4360531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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298
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Lim R, Mitsunobu K, Li WK. Maturation-stimulating effect of brain extract and dibutyryl cyclic AMP on dissociated embryonic brain cells in culture. Exp Eye Res 1973; 79:243-6. [PMID: 4350890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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299
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Lim R, Mitsunobu K. Effect of dibutyryl cyclic AMP on nucleic acid and protein synthesis in neuronal and glial tumor cells. LIFE SCIENCES. PT. 2: BIOCHEMISTRY, GENERAL AND MOLECULAR BIOLOGY 1972; 11:1063-70. [PMID: 4349502 DOI: 10.1016/0024-3205(72)90208-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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300
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Lim R, De la Torre JC, Mullan S. Protein and enzyme alterations in experimental brain injury. ARCHIVES OF NEUROLOGY 1972; 27:314-21. [PMID: 4262399 DOI: 10.1001/archneur.1972.00490160042006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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