The O4 Skin Renewal Overnight Mask combines four key strategies for visible skin improvement at the cellular level. The active ingredients target different signaling pathways and structural elements of the skin. They activate the skin's own repair mechanisms, protect and strengthen the extracellular matrix (ECM, the supporting network of collagen, hyaluronic acid, etc.) to optimize skin architecture. Together, they promote the maintenance and restoration of a dense, elastic, and even complexion.

Retinoids are among the most effective ingredients for promoting cellular activity and are essential in skincare. The 04 Skin Renewal Overnight Mask combines three different retinoids: retinal, retinyl palmitate, and Retinatural®. These complement each other through their different mechanisms of action and release profiles.

Retinal (retinaldehyde) is converted in the skin into its active form, retinoic acid. This enters the cell nucleus directly, where it activates specific receptors (RARs). There, it acts like a switch: retinal (retinaldehyde) is converted into retinoic acid in the skin. This binds to specific retinoic acid receptors (RARs) in the cell nucleus, a class of nuclear transcription factors. This binding regulates the expression of certain genes. Genes involved in the growth and differentiation of skin cells (keratinocytes), the stimulation of collagen synthesis (e.g., collagen I and III), and the stabilization of the skin structure are upregulated.

At the same time, retinoic acid inhibits the expression of genes encoding degrading enzymes such as matrix metalloproteinases (MMPs). MMPs, particularly MMP-1, -3, and -9, are enzymes that break down collagen and other components of the extracellular matrix (ECM). While this process is necessary, overactivation is associated with skin aging and loss of elasticity. Activation of retinoic acid receptors (RARs) through retinal application thus counteracts this process in two ways: it promotes cell regeneration and simultaneously inhibits the breakdown of the structure surrounding the cells. Recent reviews also show that retinoic acid promotes the production of structural proteins such as collagen type I and fibronectin while simultaneously reducing the degradation of these elements by MMPs—an effect that is also clinically relevant in wound healing (Polcz & Barbul, 2019).

In comparison, retinal's effects begin faster than those of retinol and it is also better tolerated than pure retinoic acid. Retinyl palmitate is a milder, more stable precursor. It is converted into retinoic acid through several steps, ensuring a consistent, long-lasting supply of retinoid effects. Retinatural® provides plant-based, retinoid-like substances with an affinity for retinoid receptor antagonists (RARs) without directly affecting vitamin A metabolism. Studies demonstrate an increase in epidermal thickness, improved structure, and a reduction in wrinkle depth, with good skin tolerance.

This multidimensional complex works deep within the skin, targeting its foundation: the extracellular matrix, the structure surrounding skin cells. It is based on two highly active peptide components and a biotechnologically derived hyaluronic acid fragment system. The active ingredient, palmitoyl-lysyl-dioxymethionyl-lysine (also known as palmitoyl tripeptide-38), acts as a matrikine-mimetic structure, specifically targeting the extracellular matrix, the environment surrounding skin cells where repair and structural regeneration take place. The extracellular matrix (ECM) is the structural network in the dermis, primarily composed of collagen, hyaluronic acid, elastin, fibronectin, and laminin. It provides the skin with firmness, elasticity, and volume. The second peptide, the biomimetic tripeptide, stimulates the synthesis of six essential ECM components: collagen I, III, and IV, hyaluronic acid, fibronectin, and laminin-5. These are crucial for the skin's mechanical strength, density, and elasticity. The peptide acts as a signal that enhances and maintains the natural matrix formation in the dermis, with proven efficacy in smoothing fine lines, particularly on the forehead and around the eyes. Simultaneously, the acetylated hyaluronic acid oligosaccharides promote the skin's own production of hyaluronic acid and increase the expression of transport proteins such as CD44. Studies demonstrate a significant improvement in skin hydration (+24%), a reduction in wrinkle depth (-12.5%), and a measurable smoothing of the skin surface with continuous use.

Renovage® is teprenone in a plant-based carrier oil made from caprylic/capric triglycerides, a coconut oil-glycerin blend. Teprenone is an active ingredient known from medical research with cell-protective properties and, as another active ingredient for cell regeneration, addresses age-related functional and structural changes in the skin. The active ingredient stabilizes telomeres, the protective caps at the ends of chromosomes, the shortening of which is considered a cellular aging mechanism. Through this telomere stabilization, Renovage® extends the proliferation capacity of mature skin cells by over 30% and protects them from functional loss. Furthermore, Renovage® normalizes the cellular aging marker β-galactosidase and reduces DNA damage, indicating a rejuvenation of cell function. Its efficacy is based on the ingredient geranylgeranone (GGA), a lipophilic derivative integrated into the oil phase of the formulation.

The effect of Renovage™ on functional signs of aging was investigated in a single-blind study with 24 women with a mean age of 58 ± 6 years. Participants with visible wrinkles had not used any anti-aging products for at least one month. Over a period of six months, they applied a cream containing Renovage™ at the same concentration as in the O4 Skin Renewal Overnight Mask twice daily. Sun exposure was avoided during this time. The results, measured after one and six months, show significant improvements in skin function.

Particularly impressive was the reduction of previously invisible UV-induced pigment spots, detected using the VISIA® system under UV light, an imaging technique for visualizing early light-induced skin damage such as melanin accumulation: These spots decreased by an average of 42%, and in some participants by as much as 56%. All effects were verified using standardized measurement methods (corneometry, vapometer, VISIA® analysis) and showed statistical significance. The study was conducted by the active ingredient manufacturer Sederma.

In addition to its cellular effects, the active ingredient strengthens the skin barrier, improves cohesion between skin layers, and increases capillary density. These effects promote microcirculation and improve tissue blood supply. At the same time, Renovage™ demonstrably reduces visible signs of light- and age-related skin aging, such as pore size, redness, and age spots. The effect of Renovage™ on structural signs of aging was equally significant in the study: After just one month, the skin was smoother and more even, as measurable using skin impressions that revealed fine lines, roughness, and the homogeneity of the skin surface.

After six months of use, an improvement in line homogeneity of up to +109% and a reduction in fine lines and roughness of up to -66% was observed on the décolleté.

Pore ​​size also decreased significantly. A reduction in size was visible in over 90% of the participants, as measured by the VISIA® system. The skin appeared refined and more youthful.

Furthermore, skin firmness, tone, and elasticity improved after one month in 75% of users. Redness decreased by an average of more than 30% on Doppler ultrasound after four weeks (study data: Sederma).

Panthenol supports the skin's natural regeneration processes, has a soothing effect, and binds moisture. In the skin, panthenol is converted into vitamin B5 (pantothenic acid). Vitamin B5 is an essential component of coenzyme A, a molecule that helps cells produce energy and fats such as ceramides, which are important for a strong and protected skin barrier. Panthenol can also have an anti-irritant effect by reducing the release of the inflammatory messenger interleukin-1 (IL-1). This soothes irritated or stressed skin. Studies show that panthenol accelerates re-epithelialization, the restoration of the outer layer of skin cells, while simultaneously stimulating lipid synthesis in the epidermis. This effect contributes to strengthening the skin barrier and improving the skin's ability to retain moisture. Additionally, panthenol possesses antioxidant properties and modulates pro-inflammatory processes, thereby reducing irritation and promoting skin calmness. Overall, this increases the skin's resistance to external stressors such as environmental stimuli or mechanical stress. Its good tolerability makes panthenol particularly suitable for sensitive, irritated, or stressed skin.