INTRODUCTION
The skin barrier is a highly organized system in which structural proteins, intercellular lipids, and natural moisturizing factors (NMFs) work together to maintain moisture content, regulate desquamation, and protect against environmental insults. The stratum corneum (SC), the outermost layer of the epidermis, plays a central role in these processes and serves as the primary determinant of structural integrity.1
Beyond its structural role, the stratum corneum functions as a dynamic biochemical environment in which water balance, enzymatic activity, and lipid organization are tightly interdependent. Disruption of any of these elements can impair overall barrier performance. Maintenance of adequate water content is essential not only for skin flexibility but also for the activity of enzymes involved in corneocyte desquamation.
The importance of the acidic pH of the stratum corneum, often referred to as the "acid mantle," has been well established.2 This acidic environment supports lipid-processing enzymes and serine proteases involved in desquamation, as well as antimicrobial defense mechanisms. Alterations in pH are therefore closely linked to barrier dysfunction and the development of xerotic skin conditions.
In this context, therapeutic approaches that promote both water-binding capacity and physiological pH are of particular interest. This has led to increasing interest in biomimetic strategies aimed at restoring structural elements of the stratum corneum, rather than relying solely on occlusive or water-binding effects.2,3
Natural moisturizing factors (NMFs), derived primarily from filaggrin degradation, include amino acids, pyrrolidone carboxylic acid (PCA), urea, and lactate. These hygroscopic components are essential for maintaining stratum corneum hydration, plasticity, and enzymatic activity.2,3 Lactate is a major component of natural moisturizing factor and plays a central role in both water binding and maintenance of the acidic pH environment required for optimal barrier function.4,5 Reductions in lactate and other NMF constituents have been associated with increased transepidermal water loss (TEWL), reduced water content, and impaired barrier function parameters seen in xerotic skin conditions.4,5
Conventional moisturizers typically act through occlusion or water binding; however, these approaches do not directly restore physiological constituents of the SC. In contrast, ammonium lactate takes a biomimetic approach to moisturization by replenishing endogenous components of the skin barrier. It acts as a pH-balanced source of L-lactic acid, the naturally occurring form present in human skin, thereby regulating intrinsic mechanisms of hydration and barrier homeostasis. Ammonium lactate functions as a precursor that delivers L-lactic acid, the biologically active form found in the skin. Topically, it may act as a physiologic reservoir that maintains moisture balance and barrier processes.
Although lactic acid and its derivatives have been used in dermatology for decades, the distinctions between lactate, lactic acid, and ammonium lactate have not always been clearly understood in clinical practice. More recent mechanistic insights into pH-dependent equilibrium,
Beyond its structural role, the stratum corneum functions as a dynamic biochemical environment in which water balance, enzymatic activity, and lipid organization are tightly interdependent. Disruption of any of these elements can impair overall barrier performance. Maintenance of adequate water content is essential not only for skin flexibility but also for the activity of enzymes involved in corneocyte desquamation.
The importance of the acidic pH of the stratum corneum, often referred to as the "acid mantle," has been well established.2 This acidic environment supports lipid-processing enzymes and serine proteases involved in desquamation, as well as antimicrobial defense mechanisms. Alterations in pH are therefore closely linked to barrier dysfunction and the development of xerotic skin conditions.
In this context, therapeutic approaches that promote both water-binding capacity and physiological pH are of particular interest. This has led to increasing interest in biomimetic strategies aimed at restoring structural elements of the stratum corneum, rather than relying solely on occlusive or water-binding effects.2,3
Natural moisturizing factors (NMFs), derived primarily from filaggrin degradation, include amino acids, pyrrolidone carboxylic acid (PCA), urea, and lactate. These hygroscopic components are essential for maintaining stratum corneum hydration, plasticity, and enzymatic activity.2,3 Lactate is a major component of natural moisturizing factor and plays a central role in both water binding and maintenance of the acidic pH environment required for optimal barrier function.4,5 Reductions in lactate and other NMF constituents have been associated with increased transepidermal water loss (TEWL), reduced water content, and impaired barrier function parameters seen in xerotic skin conditions.4,5
Conventional moisturizers typically act through occlusion or water binding; however, these approaches do not directly restore physiological constituents of the SC. In contrast, ammonium lactate takes a biomimetic approach to moisturization by replenishing endogenous components of the skin barrier. It acts as a pH-balanced source of L-lactic acid, the naturally occurring form present in human skin, thereby regulating intrinsic mechanisms of hydration and barrier homeostasis. Ammonium lactate functions as a precursor that delivers L-lactic acid, the biologically active form found in the skin. Topically, it may act as a physiologic reservoir that maintains moisture balance and barrier processes.
Although lactic acid and its derivatives have been used in dermatology for decades, the distinctions between lactate, lactic acid, and ammonium lactate have not always been clearly understood in clinical practice. More recent mechanistic insights into pH-dependent equilibrium,
