Inhibition of PKA Blocks Fibroblast Migration in Response to Growth Factors

The American cockroach (Periplaneta americana) is a medicinal insect. Its extract is used clinically to promote wound healing and tissue regeneration, but the effective medicinal components and mechanisms are not yet clear. It has been reported that human thymosin beta 4 (Tβ4) may accelerate skin wound healing, however, the role of P. americana thymosin (Pa-THYs) is still poorly understood. In the present study, we identify and analyze the DNA sequences of Pa-THYs by bioinformatics analysis. Then we clone, express, and purify the Pa-THYs proteins and evaluate the activity of recombinant Pa-THYs proteins by cell migration and proliferation assays in NIH/3T3 cells. To elucidate the role of Pa-THYs in wound healing, a mouse model is established, and we evaluate wound contraction, histopathological parameters, and the expressions of several key growth factors after Pa-THYs treatment. Our results showed that three THY variants were formed by skipping splicing of exons. Pa-THYs could promote fibroblast migration, but have no effect on fibroblast proliferation. In wound repair, Pa-THYs proteins could effectively promote wound healing through stimulating dermal tissue regeneration, angiogenesis, and collagen deposition. On the molecular mechanism, Pa-THYs also stimulated the expression of several key growth factors to promote wound healing. The data suggest that Pa-THYs could be a potential drug for promoting wound repair.

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Effect of growth factors on fibroblast migration in a simplified wound healing model

Biochemical Society Transactions ◽

10.1042/bst024258s ◽

1996 ◽

Vol 24 (2) ◽

pp. 258S-258S ◽

Cited By ~ 4

Author(s):

T.R. FRAY ◽

E.J. WOOD

Keyword(s):

Wound Healing ◽

Growth Factors ◽

Fibroblast Migration ◽

Wound Healing Model ◽

Healing Model

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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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Biological and biomedical applications of collagenous biomaterials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161849 ◽

1990 ◽

Vol 48 (3) ◽

pp. 856-857

Author(s):

Yasushi P. Kato ◽

Michael G. Dunn ◽

Frederick H. Silver ◽

Arthur J. Wasserman

Keyword(s):

Biomedical Applications ◽

Soft Tissues ◽

Collagen Fibers ◽

Bone Collagen ◽

Cover Slip ◽

Fibroblast Migration ◽

Cellular Expression ◽

Defect Repair

Collagenous biomaterials have been used for growing cells in vitro as well as for augmentation and replacement of hard and soft tissues. The substratum used for culturing cells is implicated in the modulation of phenotypic cellular expression, cellular orientation and adhesion. Collagen may have a strong influence on these cellular parameters when used as a substrate in vitro. Clinically, collagen has many applications to wound healing including, skin and bone substitution, tendon, ligament, and nerve replacement. In this report we demonstrate two uses of collagen. First as a fiber to support fibroblast growth in vitro, and second as a demineralized bone/collagen sponge for radial bone defect repair in vivo.For the in vitro study, collagen fibers were prepared as described previously. Primary rat tendon fibroblasts (1° RTF) were isolated and cultured for 5 days on 1 X 15 mm sterile cover slips. Six to seven collagen fibers, were glued parallel to each other onto a circular cover slip (D=18mm) and the 1 X 15mm cover slip populated with 1° RTF was placed at the center perpendicular to the collagen fibers. Fibroblast migration from the 1 x 15mm cover slip onto and along the collagen fibers was measured daily using a phase contrast microscope (Olympus CK-2) with a calibrated eyepiece. Migratory rates for fibroblasts were determined from 36 fibers over 4 days.

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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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