Skincare Products with a Heart of Gold
Endor had developed a patented method of bonding hyaluronic acid to gold. The aggregate cluster is 22 nm in size and can easily penetrate the surface of skin. The extremely high density HA-coating triggers multiple CD44 receptors on keratinocytes, which stimulates the endogenous production of new elastin, hyaluronic acid, and the signal pathway that stimulate collagen remodeling by dermal fibroblasts. The gold is inert and harmless as that absorbed from jewelry and is sloughed out of skin between topical applications.
Hyaluronic Acid and Skin Hydration
Hyaluronic Acid (HA) is a very large molecule called glycosaminoglycan containing about 20,000 disaccharide monomers averaging 3 to 7 million Daltons in mass. These are highly negatively charged aggregates that imbibe tremendous amounts of water, and function to keep skin hydrated. One third of HA is degraded and synthesized each day.. As we age the production of HA can drop to 5% of baseline!
HA is produced by keratinocytes in the epidermis and remains in skin and imbibes many time its weight of water to hydrate skin. HA molecules, typically 3,000 nm in size, are too large to penetrate the intracellular space of 15 to 50 nm so remain trapped in skin. HA is what draws water from moisturizers into the skin.
Production of HA, Elastin and Collagen in Skin
The epidermis is the outer layer of skin made up mostly of cells called keratinocytes. The keratinocytes have trigger sites on them called CD44 receptors that are sensitive to HA. if multiple receptors are triggered they stimulate the production of endogenous hyaluronic acid and elastin, and signal other cells in the dermis called fibroblasts to produce collagen. Hyaluronic acid plays a major role in wound healing, skin aging and repair.
Use of Topical HA to Trigger Production of Elastin, and Collagen
Small fragments of HA, and nano-HA, can penetrate skin, however, they just as easily leave the skin so they provide the same short term hydration as pure water. HA receptors need a minimum molecular size to trigger multiple receptors, and because of electrostatic charge the small nano-HA molecules repell each other and cannot trigger multiple receptors on kerotinocytes.
Larger HA molecules can not penetrate the surface into the epidermis, and HA that is applied topically will remain on the surface of skin and may actually pull water out and dehydrate skin!
The Endor Technologies® Solution
The solution is based on a patented method of bonding HA to 10 nm gold particles in a gold-HA complex called gold thioethylamino hyaluronic acid (AuHA™) . The highly charged part of the HA molecule bonds to the gold making the aggregate cluster very stealthy and about 22 nm in size so can easily penetrate the surface of the skin. The extremely high density HA coating triggers multiple CD44 receptors. The gold is sloughed from skin within 24 hours.
All Endor products contain AuHA™ approved in EU as a cosmetic ingredient and registered with the FDA for topical applications. Ceretox, a toxicological research center safety assessment report showed the use of the gold safe for cosmetic applications, based on toxicological profile, effect on gene expression (in vitro text at CSIC, skin absorption: Franz-cell test (IQAC lab-CSIC), Irritant potential, and patch test for human skin compatibility (Eurofins). 
Ultrasound imaging was used to evaluate the new collagen and hyaluronic acid production in the skin of 23 volunteers after 28 days of treatment. The picture shows AuHA has activated the production of new collagen and hyaluronic acid by 32% to 89% in the epidermis and 37% to 171% in the dermis.
The active ingredient in Endor products is AuHA, which is composed of gold coated with 200 and 500 oligomer HA fragments of 5,000 to 10,000 daltons in size. At 22-nm total size they are smaller than any other HA-delivery system and can easily penetrate the surface of skin into the epidermis. A low concentration of AuHA has a very powerful effect activating CD44 receptors on keratinocytes triggering the endogenous production of new HA, elastin, and collagen in skin.
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Endor Technologies® and Endor® are a registered trademarks of Endor Technologies, Barcelona, Spain.
AuHA™ is a trademark of Perigee Bioscience.