Azelaic acid. A review of its pharmacological properties and therapeutic efficacy in acne and hyperpigmentary skin disorders.
ABSTRACT Azelaic acid is a naturally occurring saturated dicarboxylic acid which, on topical application (usually as a 20% cream), has been shown to be effective in the treatment of comedonal acne and inflammatory (papulopustular, nodular and nodulocystic) acne, as well as various cutaneous hyperpigmentary disorders characterised by hyperactive/abnormal melanocyte function, including melasma and, possibly, lentigo maligna. In addition, azelaic acid has an antiproliferative and cytotoxic effect on the human malignant melanocyte, and preliminary findings indicate that it may arrest the progression of cutaneous malignant melanoma. The mechanism of this selective cytotoxic action of azelaic acid is unclear, but may possibly be related to its inhibition of mitochondrial oxidoreductase activity and DNA synthesis. In controlled studies, topical azelaic acid demonstrated comparable anti-acne efficacy to topical tretinoin, benzoyl peroxide, erythromycin and oral tetracycline, while in patients with melasma azelaic acid proved at least as effective as topical hydroquinone. On topical application azelaic acid is well tolerated, with adverse effects apparently limited to a generally mild and transient local cutaneous irritation. Thus, topical azelaic acid, employed either as monotherapy or in combination with other treatments, is likely to prove of value in the management of acne and several hyperpigmentary disorders, most notably melasma.
- SourceAvailable from: Torello Lotti
Article: Therapeutical approaches in melasma.[Show abstract] [Hide abstract]
ABSTRACT: Melasma (cloasma) is a typical hypermelanosis and a common dermatologic skin disease that involves sun-exposed areas of the skin. It mostly affects women of reproductive age. Solar and ultraviolet exposure are the most crucial etiologic factors. Pregnancy, certain endocrine disorders and hormonal treatments, cosmetics, phototoxic drugs, and antiseizure medications are well-known inducing and exacerbating factors. A classification of melasma is based on Wood's light examination, classifying it in four major clinical types and patterns: epidermal, dermal, mixed, and indeterminate. Different treatment options are currently available for melasma. The choice of proper treatment should take into account the type of melasma to be treated, the skin complexion of the patient, possible previous treatments, the expectations and compliance of the patient, and the season in which the treatment is started.Dermatologic Clinics 08/2007; 25(3):337-42, viii. DOI:10.1016/j.det.2007.04.006 · 1.43 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The type and amount of melanin synthesized by the melanocyte, and its distribution pattern in the surrounding keratinocytes, determines the actual color of the skin. Melanin forms through a series of oxidative reactions involving the amino acid tyrosine in the presence of the enzyme tyrosinase. Tyrosinase catalyses three different reactions in the biosynthetic pathway of melanin in melanocytes: the hydroxylation of tyrosine to l-DOPA and the oxidation of l-DOPA to dopaquinone; furthermore, in humans, dopaquinone is converted by a series of complex reactions to melanin. Among the skin-lightening and depigmenting agents, magnesium-l-ascorbyl-2-phosphate (MAP), hydroxyanisole, N-acetyl-4-S-cysteaminylphenol, arbutin (hydroquinone-beta-d-glucopyranoside) and hydroquinone (HQ) are the most widely prescribed worldwide. However, with reports of potential mutagenicity and epidemics of ochronosis, there has been an increasing impetus to find alternative herbal and pharmaceutical depigmenting agents. A review of the literature reveals that numerous other depigmenting or skin-lightening agents are either in use or in investigational stages. Some of these, such as kojic, glycolic and azelaic acids, are well known to most dermatologists. Others have been discovered and reported in the literature more recently. Several depigmentation and lightening agents are discussed, including their historical background, biochemical characteristics, type of inhibition and activators from various sources. In addition, the clinical importance of mushroom tyrosinase as a recent prospect is discussed in this paper.Phytotherapy Research 11/2006; 20(11):921-34. DOI:10.1002/ptr.1954 · 2.40 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Azelaic acid (AZA) has been used successfully in the treatment of lentigo maligna melanoma. Since it is generally accepted that the fibrinolytic potential of tumour cells is related to their malignant phenotype, it was the aim of this study to investigate the effect of AZA on the fibrinolytic potential of three different human melanoma cell lines (Bowes, GUBSB and MJZJ). Melanoma cells were incubated with AZA in doses ranging from 10(-2) M to 4 x 10(-2) M for 5, 8 and 24 h. The expression of tissue-type plasminogen activator (t-PA), urokinase-type PA (u-PA) and PA inhibitor-1 (PAI-1) in such treated cells was investigated by specific ELISAs on the protein level and by Northern blotting on the mRNA level. AZA caused a time and dose dependent decrease in the fibrinolytic potential of all three cell lines investigated by decreasing t-PA antigen in Bowes, by decreasing u-PA antigen in GUBSB and by increasing PAI-1 antigen in MJZJ cells, respectively. There was no significant difference between the viability of cells in control cultures and those treated with AZA. The effect of AZA on specific mRNA for t-PA in Bowes cells, u-PA in GUBSB and PAI-1 in MJZJ was consistent with its effect on the secretion of these fibrinolytic proteins by the respective cells. The results show that AZA decreases the fibrinolytic potential of the three human melanoma cell lines in vitro. This decrease may be operative in the mechanism by which AZA has been shown to affect malignant melanoma in vivo.Cancer Letters 07/1996; 103(2):125-9. DOI:10.1016/0304-3835(96)04185-7 · 5.02 Impact Factor