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Molecule which changed the view on skin treatment

Objective — to study the modern classification, mechanisms of action and clinical effects of vitamin A derivatives, to analyze retinoid for local treatment of various dermatoses with a universal mechanism of action at the epidermis and dermis levels. 
Materials and methods. A review of the literature and an analysis of the results of international clinical trials of drugs based on the natural retinoid of the first generation — tretinoin (retinoic acid) is presented. The works of dozens of authors since 1980s to the present day are analyzed. Most sources provide detailed information on the results of topical retinoids in acne therapy, which are the base of clinical guidelines. Long-term (6 months or more) studies of retinoic acid-based preparations carried out in recent decades have discovered the unique clinical effects of tretinoin in the treatment of skin photoaging, actinic keratosis, etc. They are achieved due to the effect of tretinoid on the nuclear receptors of keratinocytes and fibroblasts. 
Results and discussion. The molecular mechanisms of action of retinoic acid, realizing the cellular and tissue effects of the most studied retinoid, are systematized and grouped in a single review. It has been proven that a unique feature of tretinin is its ability to activate directly all subtypes of RARs- and, indirectly, RARs-nuclear receptors of skin cells. A new modern drug for external use is presented — AltrenoТМ lotion containing micronized 0.05 % tretinoin in combination with sodium hyaluronate, soluble collagen and glycerin. This combination exhibits the expected clinical efficacy in acne therapy and prevents side effects such as dryness, redness and exfoliation. AltrenoТМ is approved for use in children of 9 years of age and older. 
Conclusions. Tretinoin (retinoic acid) is a modern powerful retinoid with a universal mechanism of action, recommended for the treatment of acne.