Facial skin ageing: Key concepts and overview of processes

Introduction The face is a cosmetically sensitive region where the process of ageing is most clearly manifested. With increased focus on anti‐ageing and longevity, more anti‐senescent treatments are being proposed despite limited evidence. This study outlines the pathways and mechanisms underpinning the biological process of ageing in the face. Methods Comprehensive searches of MEDLINE, EMBASE, Cochrane Library and CINAHL from inception to 2020. Inclusion criteria included all empirical human research studies specific to facial ageing features, written in the English language. Results A total of 65 papers met inclusion criteria for analysis. Pathways were subdivided into intrinsic and extrinsic senescence mechanisms. Intrinsic pathways included genetics, generation of reactive oxygen species and hormonal changes. Extrinsic pathways included photoageing and damage to skin layers. The combined intrinsic and extrinsic pathway alterations result in wrinkles, higher laxity, slackness and thinning of the skin. Skin functions such as barrier immune function, wound healing, thermoregulation and sensory function are also impaired. Conclusion The ageing process is unique to the individual and depends on the interplay between an individual's genetics and external environmental factors. Through understanding the molecular and cellular mechanisms, an appreciation of the consequent structural and functional changes can be achieved. Based on this knowledge, further research can focus on how to slow or impede the ageing process and identify specific targets to develop and evolve new treatment strategies. Résumé Introduction Le visage est une zone du corps esthétiquement importante où le processus de vieillissement se manifeste particulièrement clairement. Avec l'attention croissante portée aux soins anti‐âge et à la longévité, de plus en plus de traitements anti‐sénescent sont proposés malgré des preuves d'efficacité limitées. Cette étude décrit les voies métaboliques et les mécanismes à la base du processus biologique de vieillissement du visage. Méthodes Recherches exhaustives dans les bases de données bibliographiques MEDLINE, EMBASE, Cochrane Library et CINAHL de leur création à 2020. Les critères d'inclusion comprenaient toutes les études empiriques spécifiques aux caractéristiques du vieillissement du visage chez l'Homme, rédigées en langue anglaise. Résultats Un total de 65 articles répondait aux critères d'inclusion pour l'analyse. Les voies métaboliques ont été s