Vascular endothelial growth factor behavior in different stages of tooth germ development.

BACKGROUND: Scientific studies show a possible influence of intercellular and intracellular proteins (VEGF) on the development of physiological and pathological tissue. VEGF, a key regulator of angiogenesis, it would seem essential to take action during the embryonic development of the dental germ. The purpose of the study is to investigate the importance of the enzymatic activity of VEGF through protein quantification at different stages of tooth germ development. METHODS: The quantification of VEGF protein was performed by 3 different laboratory tests: Western-blot analysis, semi-quantitative reverse transcriptase-polymerase chain reaction analysis (RT-PCR) and finally immunohistochemical analysis. Cell cultures of tooth tissue examined are: endothelial cells, stellate reticulum cells, odontoblasts and ameoblast. RESULT S: The VEGF peptide seems to induce an intense cell proliferation, not concomitant with differentiation towards the endothelial line. The expression of VEGF in the inner enamel epithelium (ameloblasts) would seem to depend on the stage of differentiation, leading us to deduce that VEGF and its respective receptor are expressed in dental germ and that induce alterations not only on the vascularization, but also on the inner epithelium activation and then on dental enamel development, respectively on cap and bell stages of embryogenesis. CONCLUSIONS: In our survey, the positive expression of VEGF in all the samples examined, might suggest a fundamental role of angiogenic gene proteins during all stages of embryonic tooth development. It is also characteristic the behavior of stellate reticulum cells, with a significant reduction in VEGF action between early and late stage, which could suggest a possible role of stellate reticulum cells, which would be able to promote and maintain an adequate energy supply to the tissues during early and late stages of differentiation and proliferation.