Azelaic acid, an ally for acne-prone skin.

According to the S.F.D. (French Society of Dermatology), 15 million people in France are affected by acne, including 3.3 million over the age of 15. This skin condition also appears among adults, and more particularly among women. That is because of their significant hormonal fluctuations. Acne outbreaks can occur on the face as well as on certain areas of the body (bust, back, buttocks, etc.). Acne is the first reason for consulting a dermatologist and can lead to a lack of self-confidence and real psychological suffering.

This chronic inflammatory disease develops at the level of the pilosebaceous follicles: the sebaceous glands secrete a sebum that is too thick or in too large a quantity, which clogs the orifices and generates pimples and blackheads. This is called dysseborrhea. In addition, in this grease-rich environment, a bacterium usually present in small quantities on the skin, Cutibacterium acnes (formerly known as Propionibacterium acnes), proliferates, causing an inflammatory response on the skin's surface. Acne is often amplified by several factors such as diet, stress, hormonal fluctuations and pollution.

Naturally present in certain cereals such as barley, azelaic acid is classified as a dicarboxylic acid. It is found in medicinal treatments against acne, applied locally, at concentrations generally ranging from 15% to 20%. Cosmetic creams and serums rarely contain more than 10% azelaic acid. However, even at this concentration, its overall anti-acne activity is relevant. Here, you can find out about azelaic acid's benefits, and it's role on several levels:

• It regulates keratinization.

  Keratinization, or cell differentiation, is a process of maturation of epithelial cells, which are loaded with keratin and end up with dead cells constituting the stratum corneum. Azelaic acid normalizes this process, resulting in a smoother skin texture and limited clogging of pores by dead cells, preventing the formation of blackheads and comedones.
  

• It fights against bacteria.

  Thanks to its antibacterial properties, azelaic acid limits the proliferation of P. acnes and S. epidermidis bacteria, which are involved in the inflammatory reactions of acne. Moreover, it acts specifically on these two microorganisms but has no harmful effects on the “good bacteria” present on the skin.

• It limits inflammation.

  Azelaic acid reduces redness, as well as the marks left by pimples: we speak of post-inflammatory erythema. Studies have shown that azelaic acid inhibits the secretion of pro-inflammatory cytokines, such as the interleukins IL-1β and IL-6, and the transcription factor TNF-α. In addition, another study showed that azelaic acid supports the regulation of kallikrein-5 in epidermal keratinocytes, all of which in turn lower cathelicidins, decreasing inflammatory processes.

• ZOUBOULIS C. C. Acne and sebaceous gland function. Clinics in Dermatology (2004).

• THIBOUTOT D. Journal of Drugs in Dermatology (2008).

• PICARDO M. & al. Azelaic acid modulates the inflammatory response in normal human keratinocytes through PPARγ activation. Experimental Dermatology (2010).

• HEGEL J. K. E. & al. Azelaic acid: Properties and mode of action. Skin Pharmacology and Physiology (2014).

• The many functions of azelaic acid. Cosmetics Buisness (2016).