Azelaic acid (AzA) is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. T ...

with the formula HOOC(CH₂)₇ COOH. This saturated dicarboxylic acid exists as a white powder. It is found in

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

, rye, and

barley Barley (''Hordeum vulgare''), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago. Globally 70% of barley p ...

. It is a precursor to diverse industrial products including polymers and plasticizers, as well as being a component of a number of hair and skin conditioners. AzA inhibits

tyrosinase Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin. The enzyme is mainly involved in two distinct reactions of melanin synthesis otherwise known as the Raper Mason pathway. Firstly, the hydroxy ...

Production

Azelaic acid is industrially produced by the

ozonolysis In organic chemistry, ozonolysis is an organic reaction where the unsaturated bonds of alkenes (), alkynes (), or azo compounds () are cleaved with ozone (). Alkenes and alkynes form organic compounds in which the multiple carbon–carbon b ...

oleic acid Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omeg ...

. The side product is nonanoic acid. It is produced naturally by '' Malassezia furfur'' (also known as ''Pityrosporum ovale''), a

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constit ...

that lives on normal

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

. The bacterial degradation of nonanoic acid gives azelaic acid.

Biological function

In plants, azelaic acid serves as a "distress flare" involved in defense responses after infection. It serves as a signal that induces the accumulation of salicylic acid, an important component of a plant's defensive response.

Applications

Polymers and related materials

Esters of this dicarboxylic acid find applications in lubrication and plasticizers. In lubricant industries it is used as a thickening agent in lithium complex grease. With hexamethylenediamine, azelaic acid forms

Nylon Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from pe ...

-6,9, which finds specialized uses as a plastic.

Medical

Azelaic acid is used to treat mild to moderate acne, both comedonal acne and inflammatory acne. It belongs to a class of medication called dicarboxylic acids. It works by killing acne bacteria that infect skin pores. It also decreases the production of

keratin Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...

, which is a natural substance that promotes the growth of acne bacteria. Azelaic acid is also used as a topical gel treatment for

rosacea Rosacea is a long-term skin condition that typically affects the face. It results in redness, pimples, swelling, and small and superficial dilated blood vessels. Often, the nose, cheeks, forehead, and chin are most involved. A red, enlarg ...

, due to its ability to reduce inflammation. It clears the bumps and swelling caused by rosacea. The mechanism of action is thought to be through the inhibition of hyperactive protease activity that converts

cathelicidin Cathelicidin antimicrobial peptide (CAMP) is a polypeptide that is primarily stored in the lysosomes of macrophages and polymorphonuclear leukocytes (PMNs); in humans, the ''CAMP'' gene encodes the peptide precursor CAP-18 (18 kDa), which is proce ...

into the antimicrobial skin peptide LL-37. In topical pharmaceutical preparations and scientific research AzA is typically used in concentrations between 15% and 20% but some research demonstrates that in certain vehicle formulations the pharmaceutical effects of 10% Azelaic acid has the potential to be fully comparable to that of some 20% creams.

Acne treatment

Azelaic acid is effective for mild to moderate acne when applied topically at a 15%-20% concentration. In patients with moderate

acne Acne, also known as ''acne vulgaris'', is a long-term skin condition that occurs when dead skin cells and oil from the skin clog hair follicles. Typical features of the condition include blackheads or whiteheads, pimples, oily skin, and ...

, twice daily application over 3 months of 20% AzA significantly reduced the number of comedones, papules, and pustules; at this strength, it’s considered to be as effective as benzoyl peroxide 5%, tretinoin 0.05%, erythromycin 2%, and oral tetracycline at 500mg-1000mg. In a comparative review of effects of topical AzA, Salicylic acid,

Nicotinamide Niacinamide or Nicotinamide (NAM) is a form of vitamin B3 found in food and used as a dietary supplement and medication. As a supplement, it is used by mouth to prevent and treat pellagra (niacin deficiency). While nicotinic acid (niacin) may ...

, Sulfur, Zinc, and alpha-hydroxy acid, AzA had more high-quality evidence of effectiveness than the rest. Results can be expected after 4 weeks of twice-daily treatment. The effectiveness of long term use is unclear, but it’s been recommended that AzA be used for at least 6 months continuously for maintenance.

Whitening agent

Azelaic acid has been used for treatment of skin pigmentation, including

melasma Melasma (also known as chloasma faciei,James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . or the mask of pregnancy when present in pregnant women) is a tan or dark ...

and postinflammatory

hyperpigmentation Hyperpigmentation is the darkening of an area of skin or nails caused by increased melanin. Causes Hyperpigmentation can be caused by sun damage, inflammation, or other skin injuries, including those related to acne vulgaris.James, William; Ber ...

, particularly in those with darker skin types. It has been recommended as an alternative to

hydroquinone Hydroquinone, also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2. It has two hydroxyl groups bonded to a benzene ring in a ''para' ...

. As a

inhibitor, azelaic acid reduces synthesis of

melanin Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino ...

. According to one report in 1988, azelaic acid in combination with

zinc sulfate Zinc sulfate is an inorganic compound. It is used as a dietary supplement to treat zinc deficiency and to prevent the condition in those at high risk. Side effects of excess supplementation may include abdominal pain, vomiting, headache, and ti ...

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology ...

was found to be a potent (90% inhibition)

5α-reductase inhibitor 5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of ...

, similar to the hair loss drugs finasteride and

dutasteride Dutasteride, sold under the brand name Avodart among others, is a medication primarily used to treat the symptoms of a benign prostatic hyperplasia (BPH), an enlarged prostate not associated with cancer. A few months may be required before benefi ...

. In vitro research during mid-1980s evaluating azelaic acid's depigmenting (whitening) capability concluded it is effective (cytotoxic to melanocytes) at only high concentrations. A 1996 review claimed 20% AzA is as potent as 4%

after a period of application of three months without the latter's adverse effects and even more effective if applied along with

tretinoin Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For leukemia, it is taken by mouth ...

for the same period of time.

Brand names

Brand names for azelaic acid include Dermaz 99, Crema Pella Perfetta (micronized azelaic acid, kojic dipalmitate, and liquorice extract), Azepur99, Azetec99, Azaclear (azelaic acid and niacinamide), AzClear Action, Azelex, White Action cream, Finacea, Finevin, Melazepam, Skinoren, Ezanic, Azelac, Azaderm, (Acnegen, Eziderm, Acnicam, Azelexin in Pakistan)

References

External links

* * {{Navbox linear saturated dicarboxylic acids 5α-Reductase inhibitors Dicarboxylic acids Anti-acne preparations