Effects of Pine Massoniana Needle Extract on Androgenetic Alopecia Model Rats via Nrf2-ARE Mediated Signaling Pathway

  OBJECTIVE  To investigate the hair growth-promoting activity and the possible mechanism of pine massoniana needle extract (PMNE) on mice by using the dihydrotestosterone (DHT) induced androgenetic alopecia (AGA) model.

  METHODS  48 C57BL/6 mice were randomly divided into 6 groups: control group without any treatment, DHT group (30 mg ·d^-1 DHT only), procyanidin group (DHT+procyanidin B2 5 mg ·kg^-1), PMNE low dose group (DHT+PMNE 4 mg ·kg^-1), PMNE medium dose group (DHT+PMNE 8 mg ·kg^-1) and PMNE high dose group (DHT+PMNE 12 mg ·kg^-1). PMNE and procyanidin B2 were given orally every day. The hair growth of mice was observed and evaluated at d7, d14, d21 and d28 after administration. The circle skins of all mice were harvested at the same depilated aera after 28 days. The hair from these skins was weighed. Some skin tissue section was obtained for HE staining, and the number of hair follicles were calculated. Some skin tissues were obtained to detect the contents of ROS and MDA and the mRNA and protein levels of Keap1, Nrf2, NQO1, HO-1 and TGF-β1 by qPCR and Western blot.

  RESULTS  PMNE promoted the hair growth of AGA mice and showed a dose-dependent effect. PMNE of 12 mg ·kg^-1 could alleviate the DHT-induced AGA in mice and achieve a similar effect to procyanidin B2. PMNE reduced the contents of ROS and MDA, promoted the mRNA and protein expressions of Nrf2, NQO1, HO-1 and reduced the mRNA and protein expressions of Keap1 and TGF-β1.

  CONCLUSIONS  PMNE can promote the hair growth of AGA mice by regulating the Nrf2-ARE signaling pathway.