INTRODUCTION
Age-related changes in the biomechanical properties of skin are important considerations for aesthetic applications including plastic surgery and dermatology, and the increasing need for effective and tolerable treatments for aging skin is underpinned by shifts in both demographics and medicine. The proportion of the world's population older than 60 years of age is expected to double from 12% to 20% between 2015 and 2050.1 As skin ages, the appearance and overall health status of skin are affected, resulting in fine lines, deep wrinkles, sagging, dryness, and rough or uneven texture.2,3 Furthermore, use of glucagon-like peptide-1 receptor agonists (GLP-1 RA) for weight loss, diabetes, and other indications is associated with undesirable cosmetic effects such as reduced facial volume, facial sagging, wrinkles, and appearance of premature aging ("semaglutide face") that can be addressed by dermatologic treatments.4,5
The dermoepidermal junction contains structural proteins, including various collagen types, laminins, and integrins, that provide structural and functional integrity to the skin.6 Skin anisotropy emerges from the alignment of collagen fibers in the dermis, resulting in directionally dependent biomechanical properties such as skin stiffness.7 Skin aging occurs from thickening of collagen fibrils and disorganization of total collagen content of dermal tissue due to a combination of chronological aging, environmental factors such as sunlight exposure and smoking, and genetic factors.2,3 Whereas younger skin is characterized by three-dimensional and pluridirectional orientation of dermal collagen fibers, collagen fibers in aged skin tend to organize in parallel with the skin surface.8 As skin ages, the appearance and overall health status of skin are affected, resulting in fine lines, deep wrinkles, sagging, dryness, and rough or uneven texture.2,3 Effects on facial skin with GLP-1 RA use include loss of dermal and subcutaneous adipose tissue
The dermoepidermal junction contains structural proteins, including various collagen types, laminins, and integrins, that provide structural and functional integrity to the skin.6 Skin anisotropy emerges from the alignment of collagen fibers in the dermis, resulting in directionally dependent biomechanical properties such as skin stiffness.7 Skin aging occurs from thickening of collagen fibrils and disorganization of total collagen content of dermal tissue due to a combination of chronological aging, environmental factors such as sunlight exposure and smoking, and genetic factors.2,3 Whereas younger skin is characterized by three-dimensional and pluridirectional orientation of dermal collagen fibers, collagen fibers in aged skin tend to organize in parallel with the skin surface.8 As skin ages, the appearance and overall health status of skin are affected, resulting in fine lines, deep wrinkles, sagging, dryness, and rough or uneven texture.2,3 Effects on facial skin with GLP-1 RA use include loss of dermal and subcutaneous adipose tissue
