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7 Anti-Angiogenesis Effect of Serpinin-RRG
The effect of human serpinin peptides on angiogenesis were assayed using the
chick chorioallantoic membrane assay (Ponce and Kleinmann 2003 ). This assay
involves the implantation of a filter paper disk embedded with serpinin peptides
on the chorioallantoic membrane (CAM) of fertilized chicken eggs. Four days
after implantation, the CAMs are fixed in 4% formaldehyde excised and the blood
capillaries recruited by the half disk are counted. Fig. 12A shows that the number
of new capillaries induced by bovine fibroblast growth factor (bFGF2) in chick
embryos were unaffected by C-terminally truncated forms of CgA [CgA(1–373),
Fig. 9 Schematic of serpinin formation its signaling pathway and PN-1-dependent biogenesis of
secretory granules in (neuro)endocrine cells. CgA is proteolytically cleaved to form serpinin which
is secreted in an activity-dependent manner. Secreted serpinin binds to a cognate receptor and
induces cAMP elevation followed by PKA activation. Then Sp1 a transcriptional factor translo-
cates into the nucleus to upregulate PN-1 transcription. The increase in PN-1 protein stabilizes the
secretory granule proteins at the Golgi apparatus to increase their levels which then promotes
biogenesis of DCG (From Kim et al. 2006 )
Y. PengfiLoh et al.