Schwann cells as putative safe host cells for Leishmania amazonensis

Submitted by Sandra Infurna ([email protected]) on 2018-12-20T14:18:35Z No. of bitstreams: 1 suzane_cortereal_etal_IOC_2009.pdf: 131775 bytes, checksum: 082ac468bc8211d57b52efeded0ebd5f (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-12-20T14:25:00Z (GMT) No. of bitstreams: 1 suzane_cortereal_etal_IOC_2009.pdf: 131775 bytes, checksum: 082ac468bc8211d57b52efeded0ebd5f (MD5)Made available in DSpace on 2018-12-20T14:25:00Z (GMT). No. of bitstreams: 1 suzane_cortereal_etal_IOC_2009.pdf: 131775 bytes, checksum: 082ac468bc8211d57b52efeded0ebd5f (MD5) Previous issue date: 2009Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Laboratório de Neurobiologia do Desenvolvimento. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Estrutural. Rio de Janeiro, RJ. Brasil.Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Laboratório de Neurobiologia do Desenvolvimento. Rio de Janeiro, RJ, Brasil

Selective stimulatory action of olfactory ensheathing glia-conditioned medium on oligodendroglial differentiation, with additional reference to signaling mechanisms

AbstractWe examined the effects of conditioned medium from olfactory ensheathing glia (OEGCM) on the differentiation of oligodendrocytes in mixed cultures of early postnatal hippocampi. Differentiation was judged from the numerical density (ND) of cells immunoreactive to 2′3′ cyclic nucleotide 3′phosphodiesterase (CNPase) and O4 antibodies. NDs increased according to inverted-U dose–response curves, particularly for CNPase+ cells (9-fold at optimal dilution) and these changes were blocked by inhibitors of ERK1, p38-MAPK, and PI3K. Our results raise the possibility that OEG secreted factor(s) may counteract demyelination induced by trauma, neurodegenerative diseases, and advanced age, and should stimulate novel methods to deliver these factors and/or potentiating chemicals

Modulators of axonal growth and guidance at the brain midline with special reference to glial heparan sulfate proteoglycans

Bilaterally symmetric organisms need to exchange information between the left and right sides of their bodies to integrate sensory input and to coordinate motor control. Thus, an important choice point for developing axons is the Central Nervous System (CNS) midline. Crossing of this choice point is influenced by highly conserved, soluble or membrane-bound molecules such as the L1 subfamily, laminin, netrins, slits, semaphorins, Eph-receptors and ephrins, etc. Furthermore, there is much circumstantial evidence for a role of proteoglycans (PGs) or their glycosaminoglycan (GAG) moieties on axonal growth and guidance, most of which was derived from simplified models. A model of intermediate complexity is that of cocultures of young neurons and astroglial carpets (confluent cultures) obtained from medial and lateral sectors of the embryonic rodent midbrain soon after formation of its commissures. Neurite production in these cocultures reveals that, irrespective of the previous location of neurons in the midbrain, medial astrocytes exerted an inhibitory or non-permissive effect on neuritic growth that was correlated to a higher content of both heparan and chondroitin sulfates (HS and CS). Treatment with GAG lyases shows minor effects of CS and discloses a major inhibitory or non-permissive role for HS. The results are discussed in terms of available knowledge on the binding of HSPGs to interative proteins and underscore the importance of understanding glial polysaccharide arrays in addition to its protein complement for a better understanding of neuron-glial interactions