Earticle

Edible bird's nest (EBN), made from the salivary excretions of the swiftlet, is one of the widely used health foods in asian communities. Until now, although EBN has been known to have immune-boosting and anti-viral activities, other functions have not been reported. This study is aimed to investigate the effects of EBN on proliferation of human adipose-derived stem cells (hADSCs) and its action mechanism. We found that EBN strongly promoted proliferation of hADSCs and nomal human fibroblasts (NHFs). Additionally, attempts to elucidate a possible mechanism underlying the EBN-mediated effects reveald that EBN induced production of IL-6 and VEGF, and that this was mediated through activation of NF-kB. Specially, WE found that production of IL-6 and VEGF was induced by EBN. In addition, EBN-induced production of IL-6 and VEGF was inhibited by PD98059, a p44/42 MAPK inhibitors, SB203580, a p38 MAPK inhibitor, and PDTC, a NF-kB inhibitor, but not SP600125, a JNK inhibitor. Similar to this, EBN-induced proliferation of hADSCs was also attenuated by PD98059, SB203580 and PDTC, but not SP600125. Taken together, these findings suggest that the EBN-induced proliferation of hADSCs primarily occurs through the increased expression of IL-6 and VEGF, which is mediated by the activation of NF-kB.

To better understand the molecular mechanisms underlying the anti-aging properties of water extract of edible bird's nest (WEBN), the effect of WEBN on oxidative stress-induced matrix metalloproteinase-1 (MMP-1) was assessed in human HaCaT keratinocyte. Upon exposure to $H_2O_2$, WEBN inhibited $H_2O_2$-induced cytotoxicity and scavenged intracellular reactive oxygen species, down-regulated $H_2O_2$-induced MMP-1 mRNA expression, protein expression and activity, and lowered the activation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinases (JNK), which are the upstream of MMP-1 expression. Furthermore, WEBN inhibited the expression of c-Fos and phospho c-Jun, which are components of the transcription factor activator protein-1 (AP-1), AP-1 transcriptional activity, and AP-1 binding to the MMP-1 promoter. These data indicate that the anti-aging properties of WEBN involve the inhibition of MMP-1 expression via down-regulation of the ERK /JNK and AP-1 pathway.