RESUMO
The search for rapid and reproducible in vivo angiogenesis and antiangiogenesis assays is an area of intense interest. These types of assays are extremely useful in testing putative drugs and biological agents and for the comparison and enhancement of in vitro tests. The Matrigel plug assay is one such assay and has proved to be a relatively quick and easy method to evaluate both angiogenic and antiangiogenic compounds in vivo. Initial indications of the levels of activity of strong angiogenic or antiangiogenic compounds can be visually assessed even as the plugs come out of the mouse because there are color differences in the plugs compared to the controls. Further quantitation is then needed to determine levels of angiogenic/antiangiogenic activity, and this can be performed using a variety of methods. This chapter presents an overview of the basic methods used to set up both angiogenic and antiangiogenic assays, discusses factors influencing variability, and discusses the methods for quantitating the plugs obtained. The Matrigel plug assay provides another useful tool in angiogenesis research.
Assuntos
Bioensaio/métodos , Colágeno/metabolismo , Laminina/metabolismo , Neovascularização Fisiológica , Proteoglicanas/metabolismo , Animais , Combinação de Medicamentos , Feminino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Acceleration of the wound healing process by using angiogenic peptides has been demonstrated previously. Here we used select laminin-111 peptides, A13 and C16, from the laminin alpha1 and gamma1 chain, respectively, to test whether they are able to stimulate wound healing in a rat full thickness wound model. The 12-mer peptides C16 and A13 are highly angiogenic and bind to integrins alphavbeta3 and alpha5beta1. We show that A13 increases wound re-epithelialization as much as 17% over controls by day 4 and C16 increases coverage by 11%. Contraction of the treated wounds was increased as much as 11% for A13 and 8% for C16 at day 4. No differences were observed at day 7 with either peptide. The peptides also stimulated fibroblast migration in Boyden chamber assays. A13 increased cell migration as much as 2.4-fold on uncoated filters and as much as 16-fold on collagen type IV-coated filters over negative controls. Similarly, C16 also stimulated migration 1.8-fold on uncoated filters and as much as 12-fold on collagen-coated filters. A13 and C16 significantly decreased expression of the pro and active forms of matrix metalloproteinase 2 in foreskin fibroblasts indicating their role in collagen accumulation. We conclude that small bioactive angiogenic peptides can promote dermal wound healing and may offer a new class of stable and chemically manipulable therapeutics for wound healing.