Heparan sulfate and cell division

Heparan sulfate is a component of vertebrate and invertebrate tissues which appears during the cytodifferentiation stage of embryonic development. Its structure varies according to the tissue and species of origin and is modified during neoplastic transformation. Several lines of experimental evidence suggest that heparan sulfate plays a role in cellular recognition, cellular adhesion and growth control. Heparan sulfate can participate in the process of cell division in two distinct ways, either as a positive or negative modulator of cellular proliferation, or as a response to a mitogenic stimulus.Universidade Federal de São Paulo (UNIFESP)UNIFESP, EPM, São PauloSciEL

CXCL12 N-terminal end is sufficient to induce chemotaxis and proliferation of neural stem/progenitor cells

Neural stem/progenitor cells (NSC) respond to injury after brain injuries secreting IL-1, IL-6, TNF-alpha, IL-4 and IL-10, as well as chemokine members of the CC and CXC ligand families. CXCL12 is one of the chemokines secreted at an injury site and is known to attract NSC-derived neuroblasts, cells that express CXCL12 receptor, CXCR4. Activation of CXCR4 by CXCL12 depends on two domains located at the N-terminal of the chemokine. in the present work we aimed to investigate if the N-terminal end of CXCL12, where CXCR4 binding and activation domains are located, was sufficient to induce NSC-derived neuroblast chemotaxis. Our data show that a synthetic peptide analogous to the first 21 amino acids of the N-terminal end of CXCL12, named PepC-C (KPVSLSYRCPCRFFESHIARA), is able to promote chemotaxis of neuroblasts in vivo, and stimulate chemotaxis and proliferation of CXCR4+ cells in vitro, without affecting NSC fate. We also show that PepC-C upregulates CXCL12 expression in vivo and in vitro. We suggest the N-terminal end of CXCL12 is responsible for a positive feedback loop to maintain a gradient of CXCL12 that attracts neuroblasts from the subventricular zone into an injury site. (C) 2013 the Authors. Published by Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Escola Paulista Med, Dept Biochem, São Paulo, BrazilUniversidade Federal de São Paulo, Neurobiol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Physiol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biophys, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biochem, São Paulo, BrazilUniversidade Federal de São Paulo, Neurobiol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Physiol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biophys, São Paulo, BrazilFAPESP: 2005/04061-8FAPESP: 2012/00652-5CNPq: 573909/2008-3]Web of Scienc

Heparan sulfates and heparins: similar compounds performing the same functions in vertebrates and invertebrates?

The distribution and structure of heparan sulfate and heparin are briefly reviewed. Heparan sulfate is a ubiquitous compound of animal cells whose structure has been maintained throughout evolution, showing an enormous variability regarding the relative amounts of its disaccharide units. Heparin, on the other hand, is present only in a few tissues and species of the animal kingdom and in the form of granules inside organelles in the cytoplasm of special cells. Thus, the distribution as well as the main structural features of the molecule, including its main disaccharide unit, have been maintained through evolution. These and other studies led to the proposal that heparan sulfate may be involved in the cell-cell recognition phenomena and control of cell growth, whereas heparin may be involved in defense mechanisms against bacteria and other foreign materials. All indications obtained thus far suggest that these molecules perform the same functions in vertebrates and invertebrates.Universidade Federal de São Paulo (UNIFESP)A02Universidade Federal do Rio Grande do NorteUniversidade de Mogi das CruzesUNIFESPSciEL

Aumento da síntese de heparam sulfato e bloqueio do ciclo celular induzidos pela ativação da proteína quinase C em células endoteliais

BV UNIFESP: Teses e dissertaçõe

Enzimas para degradação de heparina e heparam sulfato: purificação e especificidade

BV UNIFESP: Teses e dissertaçõe

HEPARAN-SULFATE PROTEOGLYCAN AND CONTROL OF CELL-PROLIFERATION - ENHANCED SYNTHESIS INDUCED BY PHORBOL ESTER (PMA) DURING G(1)-PHASE

The effect of phorbol 12-myristate-13-acetate (PMA), a tumor-promoting phorbol ester, on the synthesis of proteoglycans of endothelial cells in culture was investigated. This phorbol activates protein kinase C (PKC) when added to cells in culture. PKC, in turn, modulates the activity of growth factors. Using [S-35]-sulfate or [H-3]-glucosamine to label the proteoglycans we have observed a 4-24-fold increase of the heparan sulfate (HS) synthesis in a dose-dependent manner (0-100 ng/ml). Chondroitin sulfate (CS) synthesis was not affected by PMA. The effect of PMA could be completely abolished by a calcium ionophore (A23187). By the use of synchronized cells and PMA pulses at different periods of the cell cycle, as well as [H-3]-thymidine incorporation, we were able to show that the enhancement of heparan sulfate synthesis is most prominent during G(1). Our data suggest that the release of HS to the medium could be one of the responses of the cell to a mitogenic stimulus.ESCOLA PAULISTA MED,DEPT BIOQUIM,BR-04044020 SAO PAULO,BRAZILESCOLA PAULISTA MED,DEPT BIOQUIM,BR-04044020 SAO PAULO,BRAZILWeb of Scienc

Chondroitin sulfate proteoglycans are structural renewable constituents of the rabbit vitreous body

Purpose: To characterize the vitreous intrinsic proteoglycans, investigate their dynamics, and examine their role in the supramolecular organization of the vitreous. Methods: Vitreous from normal rabbits was collected and processed for observation with the transmission electron microscope after treatment with glycosidases. Also, rabbits were injected intravitreally with [S-35]-sodium sulfate and sacrificed at several time intervals after the injection. Proteoglycans (PGs) were assayed in the vitreous supernatant or in whole samples extracted with guanidine hydrochloride by polyacrylamide or agarose gel electrophoresis, followed respectively by fluorography or autoradiography, and ion-exchange chromatography and gel-filtration chromatography, combined with glycolytic treatment of the samples. the sulfated glycosaminoglycans (GAGs) were characterized by agarose gel electrophoresis after treating vitreous samples with protease and specific glycosidases. Results: the electron microscopic study revealed a network with hyaluronic acid ( HA) as thin threads coating and connecting collagen fibrils. the elimination of the HA coat showed chondroitin sulfate granules (8-25 nm) arranged at regular intervals on the fibril surface. the chondroitinase ABC digestion, besides removing the granules, also caused the formation of thicker bundles of the collagen fibrils. the PG and GAG analysis indicated that there are three renewable PGs in the vitreous ( e. g., one heparan-and two chondroitin-sulfate ones). Conclusions: At least one of the chondroitin sulfate PGs is involved in the interactions that occur in the vitreous structure, mainly by providing adequate spacing between the collagen fibrils, a condition that is probably required for the transparency of the vitreous.USP, Dept Biol Celular & Mol & Bioagentes Patogenicos, Fac Med, BR-14049900 Ribeirao Preto, BrazilUNESP, Dept Biol, Sao Jose Do Rio Preto, BrazilUNIFESP, Dept Bioquim, São Paulo, BrazilUNIFESP, Dept Bioquim, São Paulo, BrazilWeb of Scienc

Chondroitin sulfate proteoglycans are structural renewable constituents of the rabbit vitreous body

Purpose: To characterize the vitreous intrinsic proteoglycans, investigate their dynamics, and examine their role in the supramolecular organization of the vitreous. Methods: Vitreous from normal rabbits was collected and processed for observation with the transmission electron microscope after treatment with glycosidases. Also, rabbits were injected intravitreally with [S-35]-sodium sulfate and sacrificed at several time intervals after the injection. Proteoglycans (PGs) were assayed in the vitreous supernatant or in whole samples extracted with guanidine hydrochloride by polyacrylamide or agarose gel electrophoresis, followed respectively by fluorography or autoradiography, and ion-exchange chromatography and gel-filtration chromatography, combined with glycolytic treatment of the samples. the sulfated glycosaminoglycans (GAGs) were characterized by agarose gel electrophoresis after treating vitreous samples with protease and specific glycosidases. Results: the electron microscopic study revealed a network with hyaluronic acid ( HA) as thin threads coating and connecting collagen fibrils. the elimination of the HA coat showed chondroitin sulfate granules (8-25 nm) arranged at regular intervals on the fibril surface. the chondroitinase ABC digestion, besides removing the granules, also caused the formation of thicker bundles of the collagen fibrils. the PG and GAG analysis indicated that there are three renewable PGs in the vitreous ( e. g., one heparan-and two chondroitin-sulfate ones). Conclusions: At least one of the chondroitin sulfate PGs is involved in the interactions that occur in the vitreous structure, mainly by providing adequate spacing between the collagen fibrils, a condition that is probably required for the transparency of the vitreous.USP, Dept Biol Celular & Mol & Bioagentes Patogenicos, Fac Med, BR-14049900 Ribeirao Preto, BrazilUNESP, Dept Biol, Sao Jose Do Rio Preto, BrazilUNIFESP, Dept Bioquim, São Paulo, BrazilUNIFESP, Dept Bioquim, São Paulo, BrazilWeb of Scienc