Objective      To explore the effects of secreted Frizzled-related protein 5 (sFRP5) inhibiting Wnt3a on the melanin formation of melanocytes.       Methods      With immortalized melanocytes as model and adenoviral vectors

we set up 3 experimental groups

melanocytes transfected with Ad-GFP (Ad-GFP group)

melanocytes transfected with Ad-Wnt3a (Ad-Wnt3a group) and melanocytes transfected with Ad-Wnt3a+Ad-sFRP5 (Ad-Wnt3a+Ad-sFRP5 group) to do the following experiments

including L-dopa tyrosinase activity assay

Masson-Fontanas silver staining

for melanin formation detection

RT-PCR for testing expression of tyrosinase-related protein 1 (TRP-1) and tyrosinase (TYR)

and Western blotting for detecting the protein levels of TRP-1 and TYR in iMC23 cells.       Results      L-Dopa tyrosinase activity assay showed an obvious decrease in tyrosinase activity in the Ad-Wnt3a+Ad-sFRP5 group as compared to Ad-Wnt3a group (

P

0.05). Masson-Fontanas silver staining found that melanin in the Ad-Wnt3a+Ad-sFRP5 group was significantly lower than that in the Ad-Wnt3a group. RT-PCR results showed that the mRNA expression levels of TRP-1 and TYR were down-regulated in the Ad-Wnt3a+Ad-sFRP5 group (

P

0.05). Moreover

the protein levels of TRP-1 and TYR showed similar changes as proven by Western blotting (

P

0.05).       Conclusion      SFRP5 can suppress the melanin formation of melanocytes through Wnt3a inhibition.