Hyaluronan is also called hyaluronic acid or hyaluronate or HA. It is an anionic, non sulfated glycosaminoglycan distributed widely throughout connective, epithelial, and neural tissues. It is unique among glycosaminoglycans as it is non sulfated, forms in the plasma membrane instead of the Golgi, and can be very large, with its molecular weight often reaching the millions. One of the chief components of the extracellular matrix, hyaluronan contributes significantly to cell proliferation and migration, and may also be involved in the progression of some malignant tumors.
The average 70 kg person has roughly 15 grams of hyaluronan in the body, one-third of which is turned over (degraded and synthesized) every day. Hyaluronic acid is also a component of the group A streptococcal extracellular capsule, and is believed to play a role in virulence.
Hyaluronan is a common ingredient in skin-care products.
Hyaluronan injections are used for filling soft tissue defects such as facial wrinkles. Restylane is a common trade name for the product. Hyaluronan injections temporarily smooth wrinkles by adding volume under the skin, with effects typically lasting for six months.
Juvéderm is a bacterial hyaluronic acid injectable filler, similar to Restylane, but differing slightly in terms of effect and longevity. It is used for lip augmentation, reduction of folds and wrinkles, and removal of scars. The effects of Juvéderm treatments are also temporary, and costs are similar to those of Restylane.
Until recently, such hyaluronic acid fillers were injected using a classic sharp hypodermic needle, cutting through nerves and vessels, causing pain and bruises to the patient. Now, a new technique using a blunt-tip microcannula is employed. This technique consists of puncturing the skin with a sharp needle, then sliding the flexible and atraumatic blunt-tip microcannula under the skin, sparing nerves and vessels, therefore causing much less bruising.
The presence of hyaluronic acid in epithelial tissue has been shown to promote keratinocyte proliferation and increase the presence of retinoic acid, causing skin hydration. Hyaluronic acid’s interaction with CD44 drives collagen synthesis and normal skin function. Present in the extracellular matrix of basal keratinocytes, hyaluronic acid is critical to the structural integrity of the dermal collagen matrix. These benefits make hyaluronic acid a very effective topical humectant; however, results may only be sustained as part of an ongoing treatment program.
Besides, some pharmaceutical companies have recently invented anti-wrinkles creams based on Hyaluronic acid, and their efficiency has not been proven yet. Indeed, while some molecules have been scientifically proven to have some anti-aging capabilities when used in a cream, it is not the case with Hyaluronic acid.