Invitro effect of pine bark extract on melanin synthesis, tyrosinase activity, production of endothelin‐1, and PPAR in cultured melanocytes exposed to Ultraviolet, Infrared, and Visible light radiation

Abstract

Background: French maritime pine bark (Pinus pinaster) extract (PBE), the registered trade name of which is Pycnogenol ® , has been studied for its depigmenting action due to its antioxidant, anti-inflammatory, and anti-melanogenic activity. However, the mechanisms through which PBE are still not fully clear.Objective: Evaluate the impact of PBE on four in vitro parameters closely associated with cutaneous pigmentation, including melanin synthesis, tyrosinase activity, endothelin-1 (ED1), and production of peroxisome proliferator-activated receptor α, δ, and γ (PPAR α, δ, and γ), by studying the modulation of action of ultraviolet radiation A (UVA)/ultraviolet radiation B (UVB), infrared-A (IR-A), visible light (VL), and association of UVA/UVB, IR-A, and VL (ASS).Methods: Human melanocytes were incubated in a dry extract solution of PBE, exposed to UVA/UVB, IR-A, VL, and ASS for subsequent quantification of melanin, ED1, and PPAR α, δ, and γ. The effects of PBE on inhibition of tyrosinase activity were also performed by monophenolase activity assay.Results: UVA/UVB, IR-A, VL, and ASS radiation caused significant increases in the synthesis of melanin, ED1, and PPAR α, δ, and γ when compared to baseline control.However, PBE significantly reduced the production of melanin, ED1, and PPAR α, δ, and γ, as well as reducing about 66.5% of the tyrosinase activity.Conclusions: PBE reduces in vitro melanin production by downregulating tyrosinase and reducing pigmentation-related mediators, such as ED1 and PPAR α, δ, and γ, therefore contributing to the inhibition of pathways associated with skin hyperpigmentation.

Pycnogenol® French maritime pine bark extract in randomized, double-blind, placebo-controlled human clinical studies

“…Several mechanisms behind Pycnogenol ® ’s effects on skin have been elucidated ( 25 , 26 , 73 ). Clinical investigations of Pycnogenol ® supplementation for twelve weeks in women aged 55 to 68 years found increased hyaluronic acid synthase mRNA levels by 44% and collagen type 1 mRNA levels by 40% in skin biopsies ( 25 ).…”

“…Tyrosinase is an enzyme that activates the production of melanin, responsible for melasma in skin. In addition, Pycnogenol ® downregulated other pigmentation-related mediators in UV-light treated human melanocytes ( 73 ). Pycnogenol ® ’s ability to counteract skin hyperpigmentation was clinically validated in another study ( 26 ).…”

“…These markers are associated with long-lasting pigmentation. From these results, it was concluded that Pycnogenol ® “contributes to the inhibition of pathways associated with skin hyperpigmentation” ( 26 , 73 ).…”

The Emerging Role of Visible Light in Melanocyte Biology and Skin Pigmentary Disorders: Friend or Foe?

“…WH130, a kind of licorice extract, inhibits melanogenesis by suppressing tyrosinase activity, particularly when heated, making it a promising option for treating various disorders of hyperpigmentation, including brown spots, ephelides, and melasma [83]. French maritime pine bark extract (PBE), with its antioxidant property, has also proved to reduce VL-induced melanin synthesis in vitro, via inhibiting tyrosinase and other pigmentationrelated mediators [84]. Furthermore, a clinical study comparing antioxidant-enriched sunscreens with tinted sunscreens showed that the former had comparable or even better efficacy than the latter [85].…”