Shu Min Leticia Song1, Maria Teresa Borrello1*
1 – School of Cosmetic Science, University of Sunderland, Sunderland SR1 3SD, England
* Correspondence: Maria.Borrello@sunderland.ac.uk; Tel.: +44-748-5750-448
Abstract: Carthamus tinctorius L., commonly known as Safflower, is a thistle-like annual plant characterized by its distinctive orange flowers. It is widely used as a natural dye and colouring agent in food and cosmetics. Historically, Safflower has been used to soothe problematic skin and reduce inflammation. However, only a few studies have explored its dermatological properties. Safflower seed oil (SSO) contains luteolin, 6-hydroxykaempferol, quercetin-7-O-(6-O-acetyl)-β-D-glucopyranoside, and is particularly rich in linoleic, oleic, and linolenic acids. These components contribute to its potential use in dermatological products due to their biological activities.
We aim to uncover the potential of safflower seed oil (SSO) in promoting cell proliferation, its antioxidant, anti-inflammatory, and wound healing properties, which could be beneficial in the treatment of skin conditions. Our results on human keratinocyte cell lines (HaCaT and CCD1106 KERTr) report that SSO possesses proliferative properties and ensures cell viability. SSO also displayed potent antioxidant effects. Two methods were used to study the antioxidant capacity of the oil. SSO demonstrated significant free radical scavenging ability against 1,1-Diphenyl-2-Picrylhydrazyl Radical (DPPH). This was further supported by an in vitro assay where HaCaT cells were challenged with hydrogen peroxide, suggesting its potential as an antioxidant agent. Additionally, the anti-inflammatory potential of SSO was evaluated by measuring the inhibition of nitric oxide (NO) production using the Griess reagent method, where NO was generated from sodium nitroprusside. The results displayed that SSO contributes to decreased inflammation. Finally, we report that SSO accelerated wound closure and significantly increased cell migration at low concentrations (1 mg/mL) over a 24-hour treatment. Furthermore, SSO treatment displayed a synergistic effect when paired with Allantoin, a known agent used for wound healing properties.
This research presents promising preliminary findings on safflower seed oil for its use in the treatment of complex skin diseases such as eczema and psoriasis and include SSO in cosmetic and dermatological formulations for problematic skin.
