INTRODUCTION
Rosacea is a chronic inflammatory skin condition that affects blood vessels and pilosebaceous units.1 It is characterized by recurrent flushing, telangiectasia, central facial erythema, and papules/pustules that often present on the nose, cheek, forehead, and chin.2,3 The clinical signs and symptoms of rosacea vary but may include redness, dryness, edema, and stinging/burning.3 Rosacea can have a massive impact on patients' quality of life as those with the condition report experiencing increased anxiety, depression, and embarrassment.4-6 Despite its high burden, the choice of treatment is still challenging. The National Rosacea Society Expert Committee, American Academy of Dermatology, and National Institute of Arthritis and Musculoskeletal and Skin Diseases recommend standard management options which include topical/oral medications and laser/surgical interventions. A study by Baldwin et al7 has shown that other over-the-counter (OTC) skin care products such as IL-8, cleansers, moisturizers, and sunscreen remain instrumental in rosacea therapy.
Although retinoids are recommended for phymatous rosacea, there is a lack of OTC products to tackle the persistent facial redness many patients experience. This highlights a significant need for an efficacious, nonpharmacological treatment for the facial erythema of rosacea that can be integrated seamlessly into patients’ treatment skincare regimens.
Research suggests that rosacea's various phenotypes are a result of an immune mediated response as well as the angiogenic properties of the antimicrobial peptide LL-37, which has a high prevalence and expression level in rosacea patients.8 When bound to lipopolysaccharides (LPS) found in bacteria, LL-37 induces an inflammatory signal cascade that activates the NLRP3-mediated inflammasome, triggering skin inflammation, new blood vessel growth, and rosacea pathogenesis.9 LL-37 also induces the secretion of Th1-inducing cytokines, IL-8, generation of reactive oxygen species, and inhibition of bacterial growth. This results in a disruption of the skin barrier function which consequently enhances the entry of foreign