Milk Extracts: Nature’s Nano-Messengers for Advanced Skin Repair

What are milk extracts?

Milk extracts are endogenous extracellular vesicles naturally present in bovine milk, with a particle size ranging from 30–150 nm. Secreted by mammary epithelial cells, they exhibit a phospholipid bilayer membrane structure and function as intrinsic bioactive transport systems in mammalian milk. They contain diverse biomolecules, including mRNA, tRNA, proteins (such as HSP70, TSG101, and CD63), lipids, and bioactive peptides.

Advanced isolation techniques, combining ultracentrifugation with size-exclusion chromatography (SEC) and nanoparticle tracking analysis (NTA), achieves high purity while maintaining vesicular morphology and biological activity.

Our milk-derived extract utilizes A2 milk–sourced exosomes with ≥99% purity, delivering approximately 1.08 × 10¹⁰ nano-scale particles per single dose. Comparative permeation studies indicate 5–8-fold higher transdermal delivery efficiency relative to conventional formulations under controlled conditions.

Unique Repair Mechanism: Targeted Delivery and Precise Intervention

Milk-derived glycoprotein and phospholipid molecules are naturally expressed on the surface of milk extracts, which endows them with excellent biocompatibility and transmembrane penetration ability. After entering the skin, it can be efficiently absorbed by keratinocytes and fibroblasts, and release the contained microRNA (such as miR-148a and miR-30d) and signal proteins, directly regulating the key intracellular pathways:

• Inhibit the inflammatory pathway of NF-κB and MAPK, and significantly reduce the expression of proinflammatory factors such as IL-6 and TNF-α.
• Activate Nrf2 antioxidant pathway and increase the activities of endogenous antioxidant enzymes such as SOD and GSH-Px;
• Up-regulate the transcription of COL1A1, ELASTIN and HAS2 genes, and promote the regeneration of type I collagen, elastin and hyaluronic acid.

This process does not rely on hormonal or chemical stimulation, but instead supports physiological cell-to-cell communication to enhance structural skin resilience.

Advanced Soothing Performance: Immediate Comfort and Barrier Support

Clinical evaluation shows that the serum containing 0.5% highly active milk extracts (≥1 × 10¹⁰ particles/mL) can significantly reduce the UV-induced erythema (a* value decreased by 38.2%) within 15 minutes. Transepidermal water loss (TEWL) recovered to 92.6% of baseline levels after 48 hours, indicating enhanced barrier resilience.

Its soothing performance is supported by dual biological mechanisms:

For individuals with rosacea, steroid-dependent dermatitis, and post-procedure sensitive skin, after 28 days of continuous use, subjective stinging scores decreased by 71%, and objective erythema area was reduced by 54%.

Stimulation of Regenerative Vitality: Awakening Cellular Energy

Milk extracts penetrate the deep epidermis and enhance the activity of mitochondrial respiratory chain complexes I and IV in dermal fibroblasts, increasing ATP production by 2.3-fold and promoting cellular energy metabolism reprogramming. They also support normalization of autophagic flux and reduce the presence of aging-associated SA-β-gal positive cells.

In vitro 3D full-thickness skin models demonstrated:

This integrated mechanism of metabolic enhancement, structural reconstruction, and functional regeneration contributes to improved radiance, refined texture, and long-lasting elasticity at a physiological level.

Safety and Application

Milk extracts have been evaluated in accordance with OECD TG 404 and TG 439 guidelines, demonstrating no evidence of skin irritation, sensitization, or phototoxicity under standardized testing conditions.

Due to their high biological homology with human-derived exosomes (sequence similarity >85%), milk extracts exhibit excellent biocompatibility, minimizing cross-species limitations observed in plant-derived vesicles and reducing potential accumulation concerns associated with synthetic nanocarriers.

Bovine Milk Extracts have been listed as a cosmetic ingredient (INCI: Bovine Milk Extracts) in the Catalogue of Used Cosmetic Raw Materials in China (2021 Edition). They are currently incorporated into advanced skincare formulations designed for barrier support, post-aesthetic care, and sensitive skin applications.