Objective:

2

To explore the inhibitory effects of

Nardostachys Jatamansi DC

. volatile oil (NJVO) on psychological factors substance P (SP)/cortisol (CORT)-induced hyperpigmentation.

Methods:

2

The model of psychologically-induced hyperpigmentation of B16F10 cells was created using SP (10 nmol/L) + CORT (10 μmol/L) for 72 h. The levels of melanin content

tyrosinase (TYR) activity using NaOH lysis and L-dihydroxyphenylalanine (L-DOPA) oxidation methods were assessed

respectively. The effect of NJVO on SP/CORT-induced normal human skin tissue pigmentation was detected by Masson staining. Protein expressions of tyrosinase-related protein 1 (TRP-1)

tyrosinase-relative protein 2 (DCT)

and microphthalmia-associated transcription factor were determined using Western blot. The melanosome number

maturation

and melanosomal structure changes were detected through transmission electron microscopy and immunofluorescence experiments.

In vivo

zebrafish pigment content was evaluated in SP/CORT-induced zebrafish hyperpigmentation model.

Results:

2

NJVO significantly reduced the melanin content (

P

<

0.01) and inhibited tyrosinase activity (

P

<

0.01)

the pigmentation of the normal skin tissue in the NJVO group was significantly lower than that in the SP/CORT group (

P

<

0.05). And NJVO considerably downregulated expressions of melanogenesis-related proteins (TYR

TRP-1

DCT) in cells (

P

<

0.01). In addition

the number of melanosomes was decreased and the dentrites formation of B16F10 cells was inhibited after NJVO treatment (

P

<

0.01).

In vivo

NJVO significantly reduced the pigment content in t

he zebrafish body (

P

<

0.01).

Conclusion:

2

NJVO effectively reversed SP/CORT-induced hyperpigmentation by suppressing the activity and expression of TYR and TRPs and inhibiting melanosome maturation in mouse B16F10 melanoma cells.