The Pomegranate Flower Water Extract Negatively Regulates Melanogenesis by Suppressing MITF Expression and Its Target Enzymes

Background

The aesthetic issues caused by pigmentation are increasing people's demand for skin whitening. Considering its long-term use, it is very important for searching safe and effective agents. Pomegranate flower, a kind of traditional Chinese medicine, has shown promising anti-inflammatory, antioxidant, and antidiabetic properties, but its potential skin-lightening effects have not been well explored.

Aims

We investigated the effect of pomegranate flower water extract (PFE) on skin lightening and elucidated its underlying mechanisms.

Methods

The radical scavenging capacity was measured by ABTS and DPPH assays, and the mechanism of lightening was detected by Western blot.

Results

PFE could obviously inhibit tyrosinase activity, which its inhibition IC₅₀ value was lower than the positive control, kojic acid. Meanwhile, the radical scavenging capacity was also better than vitamin C (VC). Then the synthesis ability of melanin was measured in B16F10 cells; we found that PFE, in its safe concentrations, could reduce the synthesis of melanin resulting from inhibiting TYR activities. The expression of the main melanogenesis enzymes TYR, TRP-1, and TRP-2 was sharply reduced. Interestingly, MITF, a transcription factor of TYR, was obviously decreased its expression when treated with PFE at 50, 100, and 150 μg/mL, which was even significantly lower than the downregulation by kojic acid.

Conclusion

Pomegranate flower extract possessed a strong antimelanogenesis effect, which resulted from inhibiting the expression of MITF and its downstream target enzymes involved in melanin synthesis. These findings provide a strong scientific basis for the use of PFE as a safe and effective skin-lightening ingredient in the cosmetic industry.