Capsaicin-free red pepper extract for energized, radiant and non-irritated skin
Podium 9
Presented by: Audrey Faure-Grousson
Pollution generates reactive oxygen species (ROS) which cause cellular dysfunction and premature aging. Indeed, ROS create carbonylation, irreversible changes in proteins. Carbonylated proteins become yellowish and contribute to dull skin. In addition, mitochondria, the major source of cellular energy, is also the first intracellular target damaged by ROS. ATP production decreases, which contributes to dysfunctional cells and can alter skin regeneration potential.
Red pepper (Capsicum annuum), or Gochu, has been used in Traditional Korean Medicine (TKM) for centuries for its antimicrobial and skin regeneration properties. Renowned for its health benefits such as diabetes regulation, protection against cardiovascular diseases, natural antioxidant and energizing, it seems of particular interest for protection and stimulation of tired and stressed skin. However, red pepper also has warming properties, supported by capsaicin that activates the TRPV1 receptor on nerve endings and can lead to skin irritation and burning sensations. We especially designed a Korean red pepper capsaicin-free extract (RPE), for a safe use in cosmetic products for dull and tired skin. This extract showed antioxidant properties in the DPPH assay. We studied its effect on intracellular ROS, protein carbonylation and cells energy through ATP synthesis.
We first evaluated RPE antioxidant properties on human keratinocytes. HaCaT cells were incubated during 24 hours with RPE at different concentrations or quercetin (10 µM), a flavonoid used as a reference. Then culture medium was removed and oxidative stress was induced with H2O2 (100 µM). RPE inhibited intracellular ROS from 0.5%, and dose dependently suggesting that it stimulated the cellular antioxidant defenses. We further assessed the protective effect of RPE against particulate matter (PM)-induced protein carbonylation on human keratinocytes. We treated cells for 16 hours with RPE or references Coenzyme Q10 (10 µM) and N-acetylcysteine (NAC, 2.5 mM). Then fine dust was added in the cell medium (PM10-Like, 250 µg/mL). 24 hours later, carbonylated proteins were measured thanks to a specific fluorescent aminooxy probe. RPE prevented protein carbonylation by 38%, while NAC and Coenzyme Q10 led to 28% and 57% protection respectively.
In addition, we evaluated the effect of RPE on ATP synthesis on human dermal fibroblasts (HDF) in absence of any stress. Cells were incubated with RPE at different concentrations or Coenzyme Q10 (25 µg/mL) as a reference. RPE induced a 5-fold increase of the ATP production compared to the control while Coenzyme Q10 induced a two-fold increase. Then, HDF were exposed to fine dust (PM10-Like, 100 µg/ml) for 48h in the presence of RPE or Coenzyme Q10. Fine dust reduced ATP synthesis by 64%. In these conditions, 1 % RPE protected ATP synthesis by 53% and Coenzyme Q10 by 23%.
Finally, we demonstrated the benefit of RPE into two finish products: a cream and a mask, by evaluating clinical radiance with CLBT (Colors, Luminosity, Brightness and Transparency) method. In vivo visual evaluation of the colors by 3 trained judges is based on a structured visual scale presenting a range of the 3 main colors of facial skin (olive/yellow/pink). In vivo visual evaluation of luminosity, brightness, and transparency (LBT descriptors) by 3 trained judges is carried out using analogical scales. 32 subjects between 18 and 45 years with dull skin were selected for each study. The cream was applied once a day for 4 weeks, and the mask 2 times per week for 4 weeks. After 4 weeks of cream application, complexion brightness was increased by 13%, the luminosity by 10%, then, yellow shade was decreased by 7% (p < 1.10-3). Immediately after the first application of the mask, complexion brightness was increased by 4% (p < 1.10-3) and pinkish shade by 4% (p < 0,05).
We developed a capsaicin-free Red Pepper extract for better skin tolerance. Red Pepper extract protected proteins and cells from oxidative stress, and improved cellular energy suggesting that it could prevent visible signs of pollution, and improve dull and tired skin.
Red pepper (Capsicum annuum), or Gochu, has been used in Traditional Korean Medicine (TKM) for centuries for its antimicrobial and skin regeneration properties. Renowned for its health benefits such as diabetes regulation, protection against cardiovascular diseases, natural antioxidant and energizing, it seems of particular interest for protection and stimulation of tired and stressed skin. However, red pepper also has warming properties, supported by capsaicin that activates the TRPV1 receptor on nerve endings and can lead to skin irritation and burning sensations. We especially designed a Korean red pepper capsaicin-free extract (RPE), for a safe use in cosmetic products for dull and tired skin. This extract showed antioxidant properties in the DPPH assay. We studied its effect on intracellular ROS, protein carbonylation and cells energy through ATP synthesis.
We first evaluated RPE antioxidant properties on human keratinocytes. HaCaT cells were incubated during 24 hours with RPE at different concentrations or quercetin (10 µM), a flavonoid used as a reference. Then culture medium was removed and oxidative stress was induced with H2O2 (100 µM). RPE inhibited intracellular ROS from 0.5%, and dose dependently suggesting that it stimulated the cellular antioxidant defenses. We further assessed the protective effect of RPE against particulate matter (PM)-induced protein carbonylation on human keratinocytes. We treated cells for 16 hours with RPE or references Coenzyme Q10 (10 µM) and N-acetylcysteine (NAC, 2.5 mM). Then fine dust was added in the cell medium (PM10-Like, 250 µg/mL). 24 hours later, carbonylated proteins were measured thanks to a specific fluorescent aminooxy probe. RPE prevented protein carbonylation by 38%, while NAC and Coenzyme Q10 led to 28% and 57% protection respectively.
In addition, we evaluated the effect of RPE on ATP synthesis on human dermal fibroblasts (HDF) in absence of any stress. Cells were incubated with RPE at different concentrations or Coenzyme Q10 (25 µg/mL) as a reference. RPE induced a 5-fold increase of the ATP production compared to the control while Coenzyme Q10 induced a two-fold increase. Then, HDF were exposed to fine dust (PM10-Like, 100 µg/ml) for 48h in the presence of RPE or Coenzyme Q10. Fine dust reduced ATP synthesis by 64%. In these conditions, 1 % RPE protected ATP synthesis by 53% and Coenzyme Q10 by 23%.
Finally, we demonstrated the benefit of RPE into two finish products: a cream and a mask, by evaluating clinical radiance with CLBT (Colors, Luminosity, Brightness and Transparency) method. In vivo visual evaluation of the colors by 3 trained judges is based on a structured visual scale presenting a range of the 3 main colors of facial skin (olive/yellow/pink). In vivo visual evaluation of luminosity, brightness, and transparency (LBT descriptors) by 3 trained judges is carried out using analogical scales. 32 subjects between 18 and 45 years with dull skin were selected for each study. The cream was applied once a day for 4 weeks, and the mask 2 times per week for 4 weeks. After 4 weeks of cream application, complexion brightness was increased by 13%, the luminosity by 10%, then, yellow shade was decreased by 7% (p < 1.10-3). Immediately after the first application of the mask, complexion brightness was increased by 4% (p < 1.10-3) and pinkish shade by 4% (p < 0,05).
We developed a capsaicin-free Red Pepper extract for better skin tolerance. Red Pepper extract protected proteins and cells from oxidative stress, and improved cellular energy suggesting that it could prevent visible signs of pollution, and improve dull and tired skin.