Growth factors with valproic acid restore injury-impaired hearing by promoting neuronal regeneration

As células-tronco mesenquimais (CTM) são utilizadas na terapia celular, isolando-se de diferentes tecidos, incluindo a pele. Os fibroblastos dérmicos têm mostrado características de potência semelhantes às CTMs como expressão de marcadores de superfície e diferenciação para outros tipos de linhagens de origem mesodérmica, principalmente sob a influência de moduladores epigenéticos e fatores de crescimento. A terapia celular em medicina veterinária, especificamente em gatos, representa um desafio devido à invasividade na obtenção de tecidos fonte de CTM, para os quais outras opções menos invasivas estão sendo buscadas para an obtenção dessas células. O objetivo deste estudo foi avaliar o efeito do ácido valpróico - VPA (modulador epigenético) e fatores de crescimento (PRP e h-PDGF-B) na expressão de marcadores de superfície, genes de pluripotência e capacidade de diferenciação mesodérmica de fibroblastos felinos. Fibroblastos de pele foram isolados de gatas e cultivados com VPA e fatores de crescimento por 12 dias. A expressão de Cd90, Cd44, E-Caderina, Snail, Nanog e Oct4 foi avaliada nos dias 5 e 12. O potencial de diferenciação adipogênico, condrogênico e osteogênico dos fibroblastos foi avaliado após 12 dias de tratamento. A expressão de Cd44 aumentou no dia 5 do tratamento com VPA + PRP (p = 0,01). A expressão de Oct4 e Nanog aumentou no dia 5 do tratamento com VPA + h-PDGF-B (p 0,05). Fibroblastos em tratamento com VPA e h-PDGF-B mostraram capacidade de se diferenciar para condrogênese e osteogênese. O protocolo de cultura de células para fibroblastos felinos com VPA e h-PDGF-B confere plasticidade aos fibroblastos felinos ao promover a expressão de Nanog e Oct4, bem como a diferenciação mesodérmica in vitro.

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Retraction: Valproic acid protects neurons and promotes neuronal regeneration after brachial plexus avulsion

Neural Regeneration Research ◽

10.4103/1673-5374.317993 ◽

2022 ◽

Vol 17 (2) ◽

pp. 250

Keyword(s):

Valproic Acid ◽

Brachial Plexus ◽

Neuronal Regeneration ◽

Brachial Plexus Avulsion

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Growth factors and the primary cilium in BALB/c 3T3 cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128432 ◽

1987 ◽

Vol 45 ◽

pp. 830-831

Author(s):

R. W. Tucker ◽

N. S. More ◽

S. Jayaraman

Keyword(s):

Growth Factors ◽

Primary Cilium ◽

Cultured Cells ◽

Morphological Changes ◽

Calcium Ionophore ◽

Growth Stimulation ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

3T3 Cells ◽

Microtubule Depolymerization

The mechanisms by which polypeptide growth factors Induce DNA synthesis in cultured cells is not understood, but morphological changes Induced by growth factors have been used as clues to Intracellular messengers responsible for growth stimulation. One such morphological change has been the transient disappearance of the primary cilium, a “9 + 0” cilium formed by the perinuclear centriole in interphase cells. Since calcium ionophore A23187 also produced both mitogenesis and ciliary changes, microtubule depolymerization might explain ciliary disappearance monitored by indirect immunofluorescence with anti-tubulin antibody. However, complete resorption and subsequent reformation of the primary cilium occurs at mitosis, and might also account for ciliary disappearance induced by growth factors. To settle this issue, we investigated the ultrastructure of the primary cilium using serial thin-section electron microscopy of quiescent BALB/c 3T3 cells before and after stimulation with serum.

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New insights into heparan sulphate biosynthesis from the study of mutant mice

Biochemical Society Symposium ◽

10.1042/bss0690047 ◽

2002 ◽

Vol 69 ◽

pp. 47-57 ◽

Cited By ~ 8

Author(s):

Catherine L. R. Merry ◽

John T. Gallagher

Keyword(s):

Growth Factors ◽

Biosynthetic Pathway ◽

Heparan Sulphate ◽

Mutant Mice ◽

Gene Products ◽

Multiple Gene ◽

Adhesion Proteins ◽

Ligand Interactions

Heparan sulphate (HS) is an essential co-receptor for a number of growth factors, morphogens and adhesion proteins. The biosynthetic modifications involved in the generation of a mature HS chain may determine the strength and outcome of HS–ligand interactions. These modifications are catalysed by a complex family of enzymes, some of which occur as multiple gene products. Various mutant mice have now been generated, which lack the function of isolated components of the HS biosynthetic pathway. In this discussion, we outline the key findings of these studies, and use them to put into context our own work concerning the structure of the HS generated by the Hs2st-/- mice.

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