Pathophysiology of Acne Vulgaris
Acne vulgaris is a multifactorial disease characterized by increased sebum secretion, follicular hyperkeratosis and colonization with Cutibacterium acnes (formerly Propionibacterium acnes). Sebum secretion is regulated by androgenic hormones that stimulate sebocytes to produce triglycerides by activating lipogenic enzymes.
Follicular hyperkeratosis occurs as a result of impaired desquamation of corneocytes in the follicular canal, leading to obstruction and formation of comedones. C. acnes metabolizes triglycerides into free fatty acids, which trigger an inflammatory response by activating Toll-like receptors (TLR) and releasing pro-inflammatory cytokines.
Mechanism of Action of Niacinamide
Niacinamide (vitamin B3) modulates sebum secretion by inhibiting triglyceride synthesis in sebocytes. It acts as a cofactor for nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which participate in energy metabolism and lipid synthesis. Niacinamide also improves skin barrier function by increasing ceramide synthesis and reducing transepidermal water loss.
Salicylic Acid: Keratolytic and Antimicrobial Effect
Salicylic acid acts as a keratolytic, dissolving desmosomes between corneocytes and facilitating the removal of comedonal blockages. Thanks to its lipophilic properties, it penetrates deep into the follicular canal and dissolves sebum blocks. Salicylic acid also possesses antimicrobial properties that reduce colonization with C. acnes.
Zinc Pyrithione: Antimicrobial and Anti-inflammatory Activity
Zinc pyrithione possesses antimicrobial properties that reduce bacterial colonization and associated inflammatory processes. It inhibits the growth of C. acnes by disrupting cell membranes and metabolic processes. Additionally, zinc pyrithione modulates the inflammatory response by reducing the production of pro-inflammatory cytokines.
Application in Cosmetic Formulas
In Collagena Professional® products for problem skin, niacinamide, salicylic acid and zinc pyrithione are combined in synergistic formulas that act at different levels of acne pathophysiology. This multifactorial approach ensures effective control of sebum secretion, reduction of comedonal blockages and modulation of inflammatory processes.
