32nd IFSCC Congress (International Federation of Societies of Cosmetic Chemists), London, 19-22 september, 2022.
Ana Paula Fonseca, Carine Dal Pizzol, Samara Eberlin, Antonio Carlos Vanzo, Patrícia M. B. G. Maia Campos.
The application of antioxidants in cosmetic products contributing in collagen preservation and synthesis, acting in melanogenesis and overall skin health and appearance is improving. Thus, the objective of this study was to evaluate the efficacy and safety of a cosmetic formulation containing a blend of ingredients, such as nano ascorbyl palmitate, nano resveratrol, tocopherol, nano caffeine, carnosine and niacinamide by ex vivo and clinical evaluations. The in vitro tests were performed through the measurement of mitochondrial reactive oxygen species (mROS) in human fibroblasts cell culture after IR-A radiation and after IR-A plus treatment with the investigational product (IP). After the approval of Ethics Committee, measurements of melanin, type 1 procollagen were performed in ex-vivo human tissue from elective plastic surgery after UV radiation and after radiation plus the cosmetic treatment. In addition, filaggrin was also measured in ex-vivo human tissue, but this time after skin barrier rupture with SLS 5% and after this rupture plus investigational product treatment. Finally, a clinical study was performed by instrumental measurements in order to evaluate the skin hydration (Corneometer®), skin oiliness (Sebumeter®), collagen synthesis with diffuse reflection spectroscopy (DRS) and swelling around the eyes using Vectra XT imaging system. For this, after the approval of Ethics Committee 20 healthy females aged 40 to 50 years old, Fitzpatrick phototype II, III and IV were recruited. In addition, a self-assessment questionnaire was applied for evaluation of perceived efficacy by study participants. Safety and tolerance studies were also carried out with the product under use, as well as, acne lesions count on skin by an investigator dermatologist. The in vitro study showed that the product statistically (p<0.001) decreased mROS by -73,13% at 10.01mg/ml; -64,58% at 3.17mg/ml and -59,88% at 1mg/ml. The ex-vivo study showed that the product statistically (p<0.001) decreased melanin pigmentation by 81.53% in the irradiated and treated group, when compared to only irradiated group. Furthermore, the product statistically (p<0.001) increased type 1 procollagen by 260,40%, when compared to the only irradiated group. Also, a significant (p<0.05) increase in filaggrin production was observed when compared to the SLS ruptured and not treated group. The clinical study results showed a significant (p<0.001) decrease on skin superficial oiliness after 1 and 4 hours of IP application, when compared to the control area (non-treated) and a significant (p<0.001) increase in the dielectric constant after 1, 4, 8, 12 and 24h of product application when compared to non-treated area, suggesting an increase in the stratum corneum water content. There was no adverse event, physical sign nor reported sign, showing that the studied cosmetic product presents a high tolerance profile on normal skin. The acne lesions count presented a significant decrease in non-inflammatory lesions (p= 0,0135) and non-significant reduction in inflammatory lesions (p=0,6641). DRS results analysis showed a significant increase (p<0.05) in the values of I340/I295 (collagen/tryptophan) after 56 and 84-day period of treatment, which suggests an increase in collagen synthesis on facial skin. The Vectra XT imaging analysis showed that the cosmetic product promoted a significant (p<0.05) reduction in the swelling around the eyes in 95% of subjects after 1h of application and after 14 and 28 days of daily use in 100% of subjects (p<0.05). Finally, 120 subjects answered the self-assessment questionnaire, and the product was well appreciated by them: 91% reported their skin softer, 83% noticed an improvement in the skin overall appearance and 93% in skin hydration. The proposed cosmetic product was safe and effective in the improvement of skin conditions and appearance by increasing collagen synthesis, resulting in firmer, less rough, softer and smoother skin. The reduction of melanin and increased of filaggrin suggest a blemishes diminishment and a more hydrated skin, which was shown by Corneometer® measurements. In addition, the product was effective for application on the oily skin since it reduced the superficial sebum amount and can act in the control of skin hydrolipid balance. In the clinical evaluation the study participants also perceived the improvement of skin hydration and smoothness observed in the instrumental measurements. Finally, the present study has an important contribution since it showed the benefits of a cosmetic product based on nanoencapsulated antioxidants using different and innovative evaluation methods.
