In summer, persisting snow fields on high mountains sometimes are tinged with a reddish pink color. This phenomenon is caused by the snow algae Chlamydomonas nivalis. Snow algae are extremophile species adapted to survive on Alpine and polar snow fields. As a unicellular member of green algae, snow algae changes color by producing carotenoids containing high astaxanthin levels in their spores, which protect against ultraviolet radiation. Harnessing this extremophile survival instinct and conferring it to skin cells can extend their longevity.
A tube photobioreactor, as shown in the video below, was developed to produce snow algae raw material. In a first stage, optimal light and aeration were used to grow the green algae for three weeks through photosynthesis, in order to reach biomass. In a second stage, nutrients were reduced and light was strongly increased over two weeks to induce the formation of carotenoids and thus the red-colored spore form. Snow algae harvested at this stage was homogenized at 1200 bar in a phospholipid solution to open the cells and form liposomes with encapsulated water- and oil-soluble algae actives; i.e., snow algae extract. Finally, the liposomal extract was carefully coated onto maltodextrin in a spray granulation process (see Snow Algae Powder).
Preparations of the extremophile snow algae were then tested for anti-aging effects in vitro, in skin cell cultures, and in vivo, in clinical studies. The algae extract was found to stimulate the Klotho longevity gene and activate the protein AMPK, which is a "master switch" for cellular energy metabolism.
In vitro Efficacy
Klotho, named after a Greek goddess who spins the thread of human life, is a longevity-related gene, discovered in 1997. Mice deficient in Klotho display an accelerated aging phenotype; on the other hand, when over-expressed, the gene extends lifespan by 30%. The Klotho protein mediates its longevity effects by inhibiting insulin/IGF-1 signaling. Suppression of this signaling pathway is regarded as a central mechanism in the calorie restriction-induced longevity phenomenon.
In a replicative aging model with primary human fibroblast cells, the expression of the Klotho gene was found to be down-regulated in aged cells. However, treatment of aged cells with the snow algae extract induced an up-regulation of Klotho expression, to a value even beyond that of young cells.
The AMPK protein is a cellular sensor for energy, which is activated by an increased AMP/ATP ratio, indicating low energy. During calorie restriction and after exercise, AMPK activity is increased to restore ATP levels. However, the role of AMPK is not restricted to the control of energy metabolism. AMPK has also been shown to regulate several transcription factors related to cellular defense and protection systems, indicating its role as anti-aging factor.
In a cell culture model with primary human keratinocytes, the snow algae extract was found to stimulate the activation of AMPK.
Also in vitro, in cell culture models of primary human fibroblast cells, treatment with the snow algae extract was found to prevent aging-induced reductions in collagen production, and to protect against H2O2-induced increases in the production of matrix metalloproteinases, which are enzymes responsible for collagen degradation.
In vivo, a cream containing 3% Snow Algae Powder was tested in a placebo-controlled, half-face study for three weeks by 20 volunteers who spent the second week of the study in the harsh, winter Alpine climate. Compared with initial conditions, trans-epidermal water loss was increased, and pigment spots and eye wrinkles were worsened on the placebo-treated half of the face. However, all of these aspects were improved on the snow algae-treated half of the face, even compared with the initial study conditions (see Modification Structure).
In another clinical study, multiphoton tomography was used as a novel, non-invasive method to analyze the papillary surface area of skin. Near infrared wavelengths were used to build up a tissue contrast based either on auto-fluorescence generated, for example, by elastin and NADH; or based on second harmonic generation induced by collagen structures. The papillary surface, corresponding to the surface of the basal membrane, could be reconstructed using special software and an algorithm. Example pictures from a young and old female volunteer showed the age-related decline in papillary structures leading to a flattened basal membrane in old skin.
Finally, a cream with 2% Snow Algae Powder was applied by five women, ages 55–67, on the inner side of their forearm for two months. A placebo cream was applied to their other forearm. At the end of the study, the papillary surface increased by 12.5%, compared with initial conditions, and by 30.5% compared with the placebo, indicating a clear rejuvenation effect.