Saffron flower extract: an ingredient with multiple benefits for the skin.

The anti-inflammatory virtues of saffron extract are derived from the crocetin and crocins it contains. According to some studies, these molecules are capable of targeting the Toll-like receptors (TLR) which are involved in the regulation of various transcription factors, such as the nuclear factor (NF-κB), but also in triggering pro-inflammatory signalling pathways.

We should also note that NF-κB plays a crucial role in the production of pro-inflammatory cytokines, such as interleukins-1 and 2 (IL-1 and IL-2) and interferon-gamma (IFN-γ) in T lymphocytes. Researchers have shown that saffron can suppress the activity of NF-κB via the inhibition of IκB kinase phosphorylation.

These various properties of saffron extract make it a good ingredient for combating redness and itching. It is indeed sometimes incorporated into treatments intended for acne-prone skin.

The active ingredients found in saffron extract also enable it to protect cellular constituents from oxidative stress. For instance, safranal is capable of capturing reactive oxygen species (ROS) and enhancing the activity of antioxidant enzymes, such as superoxide dismutase (SOD) and glutathione peroxidase (GPx). These are essential proteins for the mechanism of eliminating free radicals.

Furthermore, saffron extract contains crocin and crocetin, molecules that counteract lipid peroxidation, a chain reaction leading to the damage of cell membranes and the disruption of the hydrolipidic film. Saffron extract is thus a highly valued natural ingredient for skin lacking radiance or heavily exposed to pollution. It also helps to delay skin ageing by protecting the DNA, cells and proteins of the body.

The saffron has long been used for its therapeutic and healing virtues. These come from kaempferol, a molecule that stimulates the activity of the vascular endothelial growth factor (VEGF), whose role is to trigger the formation of new blood vessels (angiogenesis). In fact, a study conducted on mice showed that a loss of activity of this growth factor present in keratinocytes delayed wound healing.

Furthermore, saffron extract increases the production ofinterleukin-6 (IL-6). Although they are considered pro-inflammatory cytokines, it is widely accepted that they possess skin regenerative activities, and they induce the migration and proliferation of keratinocytes. These various mechanisms through which saffron extract operates allow for a faster healing of minor wounds or light lesions.

Finally, saffron extract possesses moisturising properties due to the polysaccharides it contains. These arehumectant agents whose molecular structure promotes the absorption and retention of water. The moisturising power of saffron extract was indeed demonstrated in a recent study. This study involved 10 volunteers who applied a cream containing 3% saffron to their faces daily for 8 weeks.

An analysis using a cutometer subsequently demonstrated that this treatment had reduced Transepidermal Water Loss (TEWL) by 7% and increased overall skin hydration by 8%. When incorporated into a cream or lotion, saffron extract therefore contributes to skin hydration, which is essential for the skin to be supple and plump.

Studies in vitro suggest that safranal, a molecule found in saffron extract, is capable of blocking the activity of elastase, collagenase, and hyaluronidase. These three enzymes respectively catalyse the degradation of elastin, collagen, and hyaluronic acid. These molecules are essential for the suppleness, elasticity, and hydration of the skin. A decrease in any of these compounds promotes the appearance of wrinkles and skin sagging. By inhibiting these processes, saffron extract helps to delay skin ageing.

Saffron extract also possesses photoprotective virtues, derived from the safranal it contains. Studies have shown that this compound has an SPF (Sunburn Protection Factor) of 6.6, which is quite low considering that a sun care product is deemed effective when its SPF reaches 15. The SPF is the index measuring a product's ability to block UV rays responsible for sunburn. It has been demonstrated that the addition of saffron extract to a chemical-based SPF 20 sun care product can increase the SPF by 43%.

The circadian cycle, repeated every 24 hours, regulates the various biological processes of the body. Being directly exposed to light, the skin cells play a role in this cycle. During prolonged exposure to UV, this rhythm can be altered, leading to disturbances at different scales. A study in vitro, conducted on human epidermal keratinocytes, focused on the expression of circadian cycle genes. Initially at 100%, this drops to 36% after 6 hours of exposure to UVB rays. The addition of 1% saffron extract in the culture medium allows the expression of these genes to maintain at 54% after 6 hours of exposure. This ingredient therefore helps to protect the various biological processes from the deregulation caused by UV.

Due to its numerous benefits for the skin, Typology has incorporated saffron extract into its antioxidant serum. Enriched with antioxidant actives such as ferulic acid and Ashitaba extract (INCI: Angelica Keiskel Extract), this treatment protects the skin from oxidative stress caused by exposure to UV rays, pollution or tobacco.

Furthermore, it slows down skin ageing for a firmer and more radiant complexion. This serum should be applied morning and evening to a face that has been previously cleansed and dried. It is recommended to use it for at least four weeks to see the initial results.

• NAVEED A. & al. Moisturizing effect of stable cream containing Crocus sativus extracts. Pakistan Journal of Pharmaceutical Sciences (2014).

• SHOJAOSADATI S. & al. Evaluation of antioxidant activities of bioactive compounds and various extracts obtained from saffron (Crocus sativus L.): a review. Journal of Food Science and Technology (2015).

• BUTTERWECK V. & al. Saffron flower extract promotes scratch wound closure of keratinocytes and enhances VEGF production. Planta Medica (2017).