Hyaluronic Acid - More Than Moisturizing

by Ted Kalli

The Advanced Dermatologigs News, May 1994

Hyaluronic acid is a viscous macopolysaccharide acid that occurs especially in the viteous humor, the umbilical cord, and synovia and as a cementing agent in the subcutaneous tissue. New and interesting hyaluronic acid complexes have already been developed and others are under development. Test results indicate that the next generation of functional hyaluronic acid-based materials are very promising.

The following are excepts from several studies on hyaluronic acid with reference to skin wrinkles and epidermal regeneration. Complete references appear at end of article.

"Hyaluronic acid plays an important role in wound healing, favors cell proliferation, inhibits differentiation and facilitates cell migration."[1]

"Hyaluronic acid is naturally distributed throughout the human body where, among other noteworthy properties, it holds water in the intercellular matrix of dermal connective tissue and contributes to the elasticity of skin. As we age, however, the skin's hyaluronic acid (HA) content diminishes, resulting in a loss of viscoelasticity in the skin that visibly manifests itself in wrinkles. It would seem logical, then, that a personal care product that delivers hyaluronic acid to the surface of skin could help moisturize and restore elasticity, and thereby minimize the appearance of wrinkles."[2]

"Although the health care applications of hyaluronic acid have been in development for more than 50 years, it wasn't until the 1980s that this remarkable polymer sprang to the forefront of the medical and personal care fields. In opthalmology, the use of a specific hyaluronic acid preparation revolutionized the performance and success rate of cataract surgery. In the personal care field, the landmark 1982 introduction of Night Repair sparked an explosion of formulations containing HA. Today they include emulsions, eye creams, moisturizers, aerosol shave creams, hair conditioners and eyelash mascaras, to name a few."[2]

"Though hyaluronic acid's importance as moisturizing agent and protector of the cutaneous surface has been described 3-6, its regenerating activity on the epidermis in adverse situations hasn't been demonstrated. Normal skin with no apparent defects gives slow response of difficult interpretation to cosmetic or dermatological treatment.

To follow the re-ephitelization process of damaged skin, it had been the practice to eliminate horny layers by repeated strippings with adhesive tape. During a study of the effect of LMW (low molecular weight) hyaluronic acid on epidermal regeneration, morphological differences between treated and non-treated areas became apparent. These were confirmed by macrophotography and scanning electron microscopy and the images processed by means of image analyzer. These different methodologies provided sufficient information to define and quantify state of the skin, depending on treatment and course of time."[1]

"It was concluded that low molecular weight hyaluronic acid increases the hydric level of damaged skin at values similar to that of non-damaged skin, the optimum moisture being reached after 14 days. This ingredient seems to normalize migration and cell proliferation during tissue healing and at the same time diminishes cell differentiation (which otherwise could produce an abnormal accumulation of corneocytes in the horny layer and a xerotic skin appearance). Damaged skin treated with LMW hyaluronic acid is less rough than untreated skin. Furthermore, accelerated damage produced by repeated strippings tends to stimulate effects induced by adverse agents, and to accelerate the morphological/histological changes produced by these agents. LMW hyaluronic acid's high regenerative capacity has been effective in treating prematurely aged skin, induced either by chemical or by exposure to such climactic agents as UV radiation, wind, or extreme temperatures."[1]

References:

1. Casado,F.J.; Nusimovich, A. D., "LMW hyaluronic acid to induce epidermal regeneration. (low molecular weight)", Drug & Cosmetic Industry, March 1991 v148 n3 p30(4).
2. Pavlichko, Joseph; Band, P., "The Science of Minimizing Wrinkles. (lab tests prove the usefulness of hyaluronic acid in skin care), Soap-Cosmetic-Chemical Specialties, Feb 1992 v68 n2 p33(4).
3. Akasaka, H; Yamaguchi, T.; Fragrance J. 14(3), 42-47(1966).
4. Balazs, E.A.; Band, P.: Cosmetic & Toil. 99,65-8(1984).
5. Mitani, T; Hakamata K.; Sugai, T.: Nippon Koshohin Kagak. 12(l) 50-9 (1988).
6. Berardesca, E.; Gabba, P.; Borroni, G.; Rabbiosi, G.; Clin. Pharm. Res. Vill, 69-73(1988).