Skin hyperpigmentation disorders, including melasma, solar lentigines and freckles, are common dermatological concerns. These disorders are caused by excessive accumulation of melanin in the skin through a process called melanogenesis. While there are a diverse range of treatments available to manage skin hyperpigmentation, there is an ongoing quest to develop more potent and safe inhibitors of melanogenesis.
Traditional and most common topical treatments in preventing hyperpigmentation work on inhibiting tyrosinase, which is an enzyme controlling production of melanin. Alongside new natural compounds being discovered that inhibit tyrosinase much more effectively, new ways of controlling the pigmentation process are being discovered that work with a different mechanism without any effect on tyrosinase, such as our Swiss Garden Cress Sprouts Extract which you can find in our Brightening Serum. Before looking at this new mechanism, let’s go back to what triggers the pigmentation process.
Pigmentation Process and Reactive Oxidants
Over time, skin loses its glow, developing more and more age-induced or sun-induced dark spots indicating a disturbance of the pigmentation process. This complex reaction is activated by sunlight and notably by reactive oxidants generated by UV in keratinocytes. But some other factors generating oxidants and free radicals like smoke, pollution and lifestyle can lead to excess concentrations of oxidants in the skin causing premature aging and pigmentation disorders.
As we see from the below picture, UV exposure kickstarts the pigmentation process by increased production of POMC (proopiomelanocortin) which is broken down to smaller peptides, such as α-MSH resulting in increased production of melanin. (For those interested, α-MSH stimulates the melanocortin-1 receptor (MC1R) on melanocytes, resulting in increased production of eumelanin).
A New, Two Steps Mechanism of Brightening
Targeting the very first triggers in the pigmentation process, our Swiss Garden Cress Sprouts Extract interferes at two steps in the pigmentation process:
- Inhibition of α-MSH
- Neutralization of reactive oxygen species - by stimulating the cellular antioxidant defence system
To enhance absorption into the skin and to target melanocytes, garden cress sprout extract was encapsulated into plant liposomes, giving time-released activity. The extract effectively:
- Inhibits melanin formation
- Provides exceptional brightening benefits
- Fades the appearance of dark spots and discolorations
- Reduces the effects of daytime stressors
- Evens skin tone
Synergistic Effects With Classical Tyrosinase Inhibitors
The Garden Cress extract acts as an inhibitor of α-MSH and its mechanism does not affect tyrosinase activity. The clinical trials of this active showed that only 0.4% concentration inhibits melanin formation induced by α-MSH by 44 % (see picture 2). However, combination of the extract with classical tyrosinase inhibitors resulted in a synergistic effect due to different mechanisms and a 30 % stronger inhibition of the melanin synthesis (see picture 3). This is why we pair our Swiss Garden Cress Sprouts Extract in our Brightening Serum with classical tyrosinase inhibitors, such as our 7 Swiss Alpine Plants complex and the tangerine oil.
- Semantic Schollar, Melanogenesis Inhibitors by Sulekha Kumari et al.
- Science Direct, The Role of a-Melanocyte-Stimulating Hormone in Cutaneous Biology by Thomas A. Luger, Thomas Scholzen, and Stephan Grabbe
- MCBI, Skin whitening agents: medicinal chemistry perspective of tyrosinase inhibitors by Thanigaimalai Pillaiyar, Manoj Manickam, Vigneeeshwaran Namasivayam