An innovative extract of the microalga Haematococcus salinus Dunal. to fight Glyc-Aging™ and protect the skin from intense solar irradiation.
33
Presented by: Joan Attia-Vigneau
Introduction: Aging may be defined as the progressive accumulation of damage to living tissue over the organism’s lifetime. In skin, this leads to distinct structural changes affecting its appearance and physiological function. Aged skin is characterized by a loss of elasticity, the appearance of wrinkles, dryness, and reduced thickness / atrophy, among other phenotypes. External factors contributing to skin aging include sunlight, UV radiation, chemicals, pollutants, and smoking. Among the various mechanisms involved, glycation and the resulting buildup of Advanced Glycation End products (AGEs) are recognized as key drivers of cumulative skin damage and skin aging (Glyc-Aging™). Moreover, reported heightened deposition of AGEs in sun-exposed skin areas suggests that solar radiation plays an important role in the formation of AGEs.
The alga Haematococcus salinus Dunal. is a halophile microalga, adapted to withstand intense solar radiation through the production of large amounts of carotenoids. This led us to seek to capture and adapt this natural photoprotective adaptation, examine its anti-glycative potential, and adapt it to the protection of skin from photoaging and glycation-induced aging. We therefore report here on a natural, oil-soluble supercritical CO2 extract of this alga, rich in the colorless carotenoids phytoene and phytofluene. We present data demonstrating its anti-glycative and anti-inflammatory properties, and its clinical efficacy in counteracting glycation and skin aging in a high solar irradiation context.
Methods: The extract was tested in an ex-vivo model, where normal human skin explants were treated topically with the extract over 10 days. Part of the explants were examined under baseline conditions, while glycation was induced in another part using methylglyoxal (MG). N-epsilon-(carboxymethyl)lysine (CML), a classic glycation marker, was quantified in MG-induced explants by immunohistochemistry followed by image analysis. The AGE receptor (RAGE) and glyoxalase-1, both key players in the biochemistry of AGEs, were also similarly quantified in baseline explants. In an additional explant model, the extract’s effects on the levels of inflammatory interleukins IL6 and IL8 were analyzed by ELISA, while key regulator NRF2 was quantified by immunohistochemistry.
The extract was also incorporated at 1% in a simple gel-cream formulation which was tested vs. a corresponding placebo in a double-blind, 56-day trial on 25 female volunteers aged 35-60, under conditions of high solar exposure (daily beachgoing, peak summer months). Skin glycation was assessed using an AGE Reader®. The anti-inflammatory effect was evaluated via Doppler laser flowmetry measurement of skin microcirculation upon histamine stimulation, measuring the intensity and onset time of the skin’s reaction. The effect on red and UV spots was evaluated by cross-polarized image analysis (VISIA-CA). The effect on wrinkling and skin roughness was evaluated by 3D image analysis (AEVA-HE). Skin biomechanics were assessed using a Cutometer.
Results: In the explant model, the extract exhibited clear anti-glycation and anti-inflammatory activities, showing strongly reduced formation of CML upon exposure to methylglyoxal, reduced RAGE levels, significantly reduced interleukins IL6 and IL8, and increased levels of NRF2.
In the clinical trial under intense solar exposure, in comparison with the placebo, the extract significantly reduced the skin’s glycation scores; exhibited anti-inflammatory effects by strongly reducing red spots and increasing the skin’s resiliency to challenge with histamine; reduced formation of UV spots; reduced skin roughness; significantly improved skin elasticity and firmness; and delivered strong improvements in wrinkling parameters. Notably, while in many cases, data obtained with the placebo clearly showed the worsening expected under the study’s intense solar exposure conditions, treatment with the extract was able to not only prevent this worsening but also bring a net improvement vs. D0.
Conclusion: These results demonstrate the value of this Haematococcus salinus Dunal. extract, rich in the colorless carotenoids phytoene and phytofluene, as an antiglycative, anti-inflammatory and anti-aging active ingredient, including in contexts of high solar irradiation.
The alga Haematococcus salinus Dunal. is a halophile microalga, adapted to withstand intense solar radiation through the production of large amounts of carotenoids. This led us to seek to capture and adapt this natural photoprotective adaptation, examine its anti-glycative potential, and adapt it to the protection of skin from photoaging and glycation-induced aging. We therefore report here on a natural, oil-soluble supercritical CO2 extract of this alga, rich in the colorless carotenoids phytoene and phytofluene. We present data demonstrating its anti-glycative and anti-inflammatory properties, and its clinical efficacy in counteracting glycation and skin aging in a high solar irradiation context.
Methods: The extract was tested in an ex-vivo model, where normal human skin explants were treated topically with the extract over 10 days. Part of the explants were examined under baseline conditions, while glycation was induced in another part using methylglyoxal (MG). N-epsilon-(carboxymethyl)lysine (CML), a classic glycation marker, was quantified in MG-induced explants by immunohistochemistry followed by image analysis. The AGE receptor (RAGE) and glyoxalase-1, both key players in the biochemistry of AGEs, were also similarly quantified in baseline explants. In an additional explant model, the extract’s effects on the levels of inflammatory interleukins IL6 and IL8 were analyzed by ELISA, while key regulator NRF2 was quantified by immunohistochemistry.
The extract was also incorporated at 1% in a simple gel-cream formulation which was tested vs. a corresponding placebo in a double-blind, 56-day trial on 25 female volunteers aged 35-60, under conditions of high solar exposure (daily beachgoing, peak summer months). Skin glycation was assessed using an AGE Reader®. The anti-inflammatory effect was evaluated via Doppler laser flowmetry measurement of skin microcirculation upon histamine stimulation, measuring the intensity and onset time of the skin’s reaction. The effect on red and UV spots was evaluated by cross-polarized image analysis (VISIA-CA). The effect on wrinkling and skin roughness was evaluated by 3D image analysis (AEVA-HE). Skin biomechanics were assessed using a Cutometer.
Results: In the explant model, the extract exhibited clear anti-glycation and anti-inflammatory activities, showing strongly reduced formation of CML upon exposure to methylglyoxal, reduced RAGE levels, significantly reduced interleukins IL6 and IL8, and increased levels of NRF2.
In the clinical trial under intense solar exposure, in comparison with the placebo, the extract significantly reduced the skin’s glycation scores; exhibited anti-inflammatory effects by strongly reducing red spots and increasing the skin’s resiliency to challenge with histamine; reduced formation of UV spots; reduced skin roughness; significantly improved skin elasticity and firmness; and delivered strong improvements in wrinkling parameters. Notably, while in many cases, data obtained with the placebo clearly showed the worsening expected under the study’s intense solar exposure conditions, treatment with the extract was able to not only prevent this worsening but also bring a net improvement vs. D0.
Conclusion: These results demonstrate the value of this Haematococcus salinus Dunal. extract, rich in the colorless carotenoids phytoene and phytofluene, as an antiglycative, anti-inflammatory and anti-aging active ingredient, including in contexts of high solar irradiation.