The main purpose of this study is to investigate the effect of
platelet derived wound healing formula (
PDWHF) and
nerve growth factor (
NGF) in the treatment of experimental
spinal cord injury.
PDWHF is a conglomerate of
growth factors which include
platelet derived growth factor (PDGF), platelet derived
angiogenesis factor (PDAF),
transforming growth factor-beta (
TGF beta) and platelet
factor IV (PF4). Complete
spinal cord transection was performed at T12 in rats and the treatment of the
spinal cord injury was achieved by filling the dead space with
type 1 collagen gel impregnated with
PDWHF, or with 2.5S-NGF. Controls were treated with only
type 1 collagen gel. Animals were sacrificed at 1, 2 or 3 months. Histopathologically, tissue
autolysis and cavity formation by phagocytosis expanded 1-3 mm into the cord stumps and the volume of cavitation was less in the two treated groups. In the
NGF group, a greater number of surviving nerve cells were observed in this region. Most of the control animals formed only thin, short axonal bundles, however, increased axonal regrowth was noted in animals treated with trophic factors, especially in the
NGF group. The
NGF group formed thick axonal bundles and abundant
neuroma. Increased angiogenesis was observed in the
collagen gel matrix and the injured spinal cord parenchyma, in the
PDWHF group. Recent studies have shown that mammalian adult CNS possesses the ability for structural and/or functional plasticity following injury under appropriate circumstances. In this in vivo study, exogenous
NGF appeared to induce axomal outgrowth and nerve cell survival.
PDWHF produced notable angiogenesis which seemed to improve the extracellular microenvironment. This may be important for the delivery of exogenous trophic factors, nutrients and for the changes of extracellular matrices to support nerve cells and axons.