Cosmeceuticals Part 4

Depigmenting agents

Hyperpigmentation is the result of an increased amount of melanin in the epidermis, the dermis, or both. This pigmentary change can be divided into 2 pathophysiologic processes: melanocytosis (increased number of melanocytes) and melanosis (increased amount of melanin). Depigmenting agents work best when melanosis or melanocytosis is restricted to the
epidermis. Other methods of depigmentation being used are chemical peels.

Depigmenting agents can be divided into several groups:

Phenolic compounds include the following:

Nonphenolic compounds include the following:

Combination formulas include the following:

Other Cosmeceuticals

Botanicals

Because of the awareness of the environmental damage caused by industrialization, a trend has developed to use products with natural ingredients. No other ingredient can serve this purpose as well as botanicals. Botanicals are now
part of every product in the market from cosmetics to soft drinks. Avocado, banana, lemon, and other similar botanicals are listed on thousands of labels. They exert their purported effects through the mechanisms of antioxidants, AHAs, BHAs, and other unclear properties.

Some examples of botanicals include chamomile, which inhibits the release of histamine and has anti-inflammatory properties, and ginseng, which stimulates the biosynthesis of proteins, RNA, and lipids. Ginkgo biloba
extract was found to locally induce SOD and to catalase enzyme activity in the epidermis after topical application as well as to systemically increase the activity of both enzymes in the liver, the heart, and kidneys. Curcumin found in curry has anti-inflammatory activity by inhibiting leukotriene formation, inhibiting platelet aggregation, and stabilizing neutrophilic lysosomal membranes. Glycyrrhizin found in licorice roots inhibits proinflammatory activities of prostaglandins and leukotrienes. Capsaicin inhibits substance P, a peptide transmitter of the inflammatory process. Aloe vera has been shown to accelerate wound healing and to protect and sooth the skin.

Glycosaminoglycans

Hyaluronic acid (HA), or hyaluronan, is the prototype of all other GAGs. Studies have demonstrated that decreased amounts are present in aged skin and that topically applied HA accelerates wound repair. Other studies have
noted epidermal regeneration after the application of low-molecular-weight HA.

Anticellulites

Lipolysis is mediated, in part, by beta-adrenergic receptors, which induces fat breakdown, and alpha2-adrenergic receptors, which inhibits fat breakdown. Agents that bind to these receptors may hypothetically serve a therapeutic effect on cellulite. Beta-adrenergic stimulators include theobromine, theophylline, aminophylline, caffeine, isopropylarterenol hydrochloride, and epinephrine. Alpha2-adrenergic inhibitors include yohimbine, piperoxan, phentolamine, and dihydroergotamine.

Enzymes

Papain

Papain, an enzyme found in the papaya fruit, chemically digests intercellular bonds. Papain has been studied in the treatment of hypertrophic scars, and it can be used to exfoliate keratotic skin.

Deoxyribonucleic acid (DNA) repair enzymes

UV-B radiation–induced cyclobutane pyrimidine dimers in the DNA of epidermal cells are detrimental to human health by causing mutations and immunosuppressive effects that contribute to photocarcinogenesis. Lotions containing bacteria-derived DNA repair enzymes, and photolyase-containing liposomes have been shown to reduce the incidence
of cancerous and precancerous lesions. When the bacterial DNA repair enzyme T4 endonuclease V is intracellularly delivered, it increases the rate of repair of sunlight-induced DNA damage in human cells.