Skin ageing is a natural, multifactorial and still little-known process which results both from intrinsic factors (genomic, hormonal, etc.) and from external aggravating factors (UV radiation, pollution, food, free radicals, etc.). The latter are referred to as accelerated ageing or as photo-ageing in the particular case of UVs.
Intrinsic ageing and accelerated ageing have slightly different phenotypic characteristics. Intrinsic ageing is characterized by skin dryness, fine wrinkles and a loss of adipose tissue. Photo ageing is characterized by a significant loss of firmness and elasticity (loose skin), deeper wrinkles and pigmentation disorders.
In the past few years, significant progress has been made in the understanding of cell ageing mechanisms and we can now explore new dermo-cosmetics strategies which might prevent or decelerate the signs of ageing.
Skin ageing: in vitro models and assays
Bioalternatives has many in vitro models at your disposal:
- intrinsic ageing model:
- “aged” human dermal fibroblasts (Hayflick model)
- “aged” dermal equivalent (Hayflick model)
- accelerated ageing model:
- human dermal fibroblasts aged by oxidative stress (H2O2)
- human reconstructed skin in deficient medium
- photo-ageing model:
- human dermal fibroblasts subjected to UVA, infrared or UV radiation
- photo-aged human full thickness reconstructed skin
on which we can evaluate the anti-ageing effect of active cosmetic compounds on:
- cell renewal (cell proliferation, migration and differentiation)
- extracellular matrix synthesis and degradation (collagen, elastin, hyaluronic acid, MMPs, etc.)
- senescence marker expression
- free radical production
Here are a few examples among all standard assays proposed by Bioalternatives in the field of skin ageing:
Skin ageing: clinical bioanalysis
Analysis of lipids involved in the barrier function
Our company has developed ready-to-use non-invasive collection kits to analyze the lipids and biomarkers of the skin surface from your samples or from those of your clinical center.
The epidermal lipids involved in the barrier function of the epidermis (ceramides, fatty acids and cholesterol) are removed using the SW Kit.
The analysis of these lipids makes it possible to evaluate the quality of the intercorneocyte cement involved in the barrier function of the epidermis and in the prevention of transepidermal water loss (TEWL).
These evaluations help support your claims about the efficacy of biomimetic products, barrier products, protective products, moisturizers, etc.
Analysis of the components of the Natural Moisturizing Factor (NMF)
The amino acids and minerals present on the surface of the skin are collected using the SW Kit:
- PCA / UCA (cis/trans) – (catabolites of filaggrin)
- Amino acids
- Urea, lactates
- Mineral elements: Ca, K, Na, Mg, Zn, etc.
The analysis of these compounds makes it possible to evaluate the impact of the NMF component on skin hydration
These analysis help support your claims about the efficacy of hygroscopic products, barrier products, protective products, moisturizers, etc.
Analysis of markers of oxidative stress
Oxidative stress is also a factor of accelerated skin ageing. Oxidative stress markers are analyzed from samples using the SW Kit. The sampling areas depend on the type of stress (induced stress or external environment).
The analyzed markers are:
- products from peroxidation and lipid detoxification (MDA, peroxidized squalene, CAT, SOD, etc.)
- protein oxidation products (AOPP Dityrosin, ROH, etc.)
These evaluations help support your claims about the efficacy of anti-pollution products, protective products , anti-aging products, etc.
Ceramide screening – LC/MS
Damaged and healthy corneocytes – SEMX500
PCA analysis – LC/UV