Skin photoprotective and antiageing effects of a combination of rosemary (Rosmarinus officinalis) and grapefruit (Citrus paradisi) polyphenols

Abstract

BackgroundPlant polyphenols have been found to be effective in preventing ultraviolet radiation (UVR)-induced skin alterations. A dietary approach based of these compounds could be a safe and effective method to provide a continuous adjunctive photoprotection measure. In a previous study, a combination of rosemary (Rosmarinus officinalis) and grapefruit (Citrus paradisi) extracts has exhibited potential photoprotective effects both in skin cell model and in a human pilot trial.ObjectiveWe investigated the efficacy of a combination of rosemary (R. officinalis) and grapefruit (C. paradisi) in decreasing the individual susceptibility to UVR exposure (redness and lipoperoxides) and in improving skin wrinkledness and elasticity.DesignA randomised, parallel group study was carried out on 90 subjects. Furthermore, a pilot, randomised, crossover study was carried out on five subjects. Female subjects having skin phototype from I to III and showing mild to moderate chrono- or photoageing clinical signs were enrolled in both studies. Skin redness (a* value of CIELab colour space) after UVB exposure to 1 minimal erythemal dose (MED) was assessed in the pilot study, while MED, lipoperoxides (malondialdehyde) skin content, wrinkle depth (image analysis), and skin elasticity (suction and elongation method) were measured in the main study.ResultsTreated subjects showed a decrease of the UVB- and UVA-induced skin alterations (decreased skin redness and lipoperoxides) and an improvement of skin wrinkledness and elasticity. No differences were found between the 100 and 250 mg extracts doses, indicating a plateau effect starting from 100 mg extracts dose. Some of the positive effects were noted as short as 2 weeks of product consumption.ConclusionsThe long-term oral intake of Nutroxsun™ can be considered to be a complementary nutrition strategy to avoid the negative effects of sun exposure. The putative mechanism for these effects is most likely to take place through the inhibition of UVR-induced reactive oxygen species and the concomitant inflammatory markers (lipoperoxides and cytokines) together with their direct action on intracellular signalling pathways.

Nutraceuticals for Skin Care: A Comprehensive Review of Human Clinical Studies

“…Other studies based on procyanidin-based polyphenolic extracts provided conclusive results on the inhibition of UV-induced age spots due to the high number of subjects utilised [ 92 ]. The efficacy of rosemary and citrus polyphenols to reduce skin redness and MED and to improve skin elasticity and decrease wrinkle depth in correlation to a decrease in skin lipid oxidation was also consistently proven [ 96 ], and a mechanistic rationale was also provided in skin cell model [ 95 ]. A red orange extract enriched in anthocyanins [ 97 ] and Polypodium leucotomos extract [ 98 , 99 ] also exhibited evidence of improvement in several skin signs related to photo-aging (erythema, hydration, elasticity and pigmentation), but with a much lower number of subjects, which compromises the consistency of the results.…”

“…After 2 weeks of product consumption, results showed decreasing wrinkle depth and increasing elasticity at 100 and 250 mg extracts dose regimens. At 2 weeks of product use, results showed decreasing wrinkle depth and increasing elasticity at 100 and 250 mg extracts dose regimen [ 96 ]. In this second study, number of subjects was high and statistically significant differences were confirmed in MED and also in wrinkle depth, elasticity and skin lipoperoxides between placebo and intervention groups.…”

Oral Photoprotection: Effective Agents and Potential Candidates

“…Citrus contains a large amount of flavonoids, and rosemary is rich in polyphenols and diterpenes. In humans, oral administration of a combination of citrus and rosemary extracts decreased sensitivity to erythema induced by UVR, as quantified by an increased MED that after 8 weeks of treatment ranged from 34% in Perez-Sanchez's study ( 85 ) to 29.8% in Nobile's study ( 86 ).…”

Plant extracts and natural compounds used against UVB-induced photoaging

“…Grapefruit is rich in phenolic compounds, among which gallic acid (GA) is the most abundant (Nobile et al 2016). In a study conducted by Pérez-Sánchez and colleagues cultivation of human keratinocytes, prior to UVB irradiation, in the presence of grapefruit extract alone (12.5–100 µg/mL) or in combination with rosemary extract (12.5–100 µg/mL), which is also rich in GA, was investigated.…”