After nerve injury, adult sensory neurons can regenerate peripheral axons and reconnect with their target tissue. Initiation of outgrowth, as well as elongation of neurites over long distances, depends on the signaling of receptors for neurotrophic growth factors. Here, we investigated the importance of gp130, the signaling subunit of neuropoietic cytokine receptors in peripheral nerve regenera...

Local delivery of neurotrophic factors is a pillar of neural repair strategies in the peripheral nervous system. The main disadvantage of the free growth factors is their short half-life of few minutes. In order to prolong their activity, we have conjugated to iron oxide nanoparticles three neurotrophic factors: nerve growth factor (βNGF), glial cell-derived neurotrophic factor (GDNF), and basi...

Partial denervation or paralysis of adult skeletal muscle is followed by nerve sprouting, probably due to release of diffusible sprout-inducing activity by inactive muscle. Insulin-like growth factors (IGF1 and IFG2) are candidates for muscle-derived sprouting activity, because (a) they induce neurite growth from peripheral neurons in vitro; and (b) their mRNA levels in adult skeletal muscle in...

Nerve growth factors (NGF's) were purified from mouse submaxillary gland, guinea pig prostate gland, bovine seminal plasma, and venom of Naja naja atra, and their biochemical and immunological properties were compared. The NGF's from the four sources stimulated the maximal response of nerve fiber outgrowth from chick dorsal root ganglia at 10 ng/ml. Two-site enzyme immunoassay (ETA) systems for...

Schwann cells are essential facilitators of peripheral nerve regeneration following injury, as they provide physical support and guidance. In vitro these supporting cells are slow-growing and hence are not well suited to a tissue-engineering approach to nerve repair. We have differentiated rat bone-marrow-derived mesenchymal stem cells into Schwann-cell-like cells using a cocktail of growth fac...

Traumatic injuries resulting in peripheral nerve lesions lead to important morbidity with devastating social and economic consequences. When the lesioned nerve cannot be sutured directly, a nerve graft is generally required to bridge the gap. Although autologous nerve grafting is still the first choice for reconstruction, it has the severe disadvantage of the sacrifice of a functional nerve. Re...

Although trophic factors and neuronal activity have been implicated in regulating functional synaptic circuits, the relationship of trophic interaction to impulse activity in synaptogenesis remains unclear. Using cultured hippocampus as a model system, we provide direct evidence that depolarization and impulse activity specifically increase nerve growth factor gene expression in neurons. Depola...

It is well known that various markers of the cholinergic synapse are altered in Alzheimer's Disease. Much interest is currently focussing on the evaluation of the possible efficacy of certain growth factors, especially nerve growth factor (NGF), to reduce or reverse cholinergic neuronal losses. Here we report that other growth factors (epidermal growth factor and insulin-like growth factor I) a...

In a wounded nerve fiber, the distal segment separated from the nerve cell body, suffer an anterograde or Wallerian degeneration and within the proximal segment of the axon appear a retrograde or traumatic degeneration. The regeneration of peripheral nervous fibers is a complex process, with multiple interactions. The factors that are stimulating the regeneration of the peripheral nervous fiber...

INTRODUCTION Delays in surgical repair following nerve transection produce progressively inferior motor nerve regeneration. Regeneration can be improved with delivery of exogenous growth factor. We developed a delivery system that could be applied at the nerve repair site to deliver growth factors locally to regenerating nerve. METHODS Poly(lactic-co-glycolic acid) microspheres containing gli...