Natural moisturizing factors

The most superficial layer of skin is the stratum comeum (SC), which consists of terminally differentiated keratinocytes (comeocytes) that originate from actively proliferating keratinocytes in lower epidermis (basale, spinosum, and granulosum cells), and contain a lamellar lipid layer secreted from lamellar bodies (Fig. 7a). Flydration of the SC is an important determinant of skin appearance and physical properties, and depends on a number of factors including the external humidity, and its structure, lipid/protein composition, barrier properties, and concentration of water-retaining osmolytes (natural moisturizing factors, NMFs) including free amino acids, ions, and other small solutes. 

Special honors are also due to S. Jacobi, who like Irwin Blank was not a clinician but a Ph.D. scientist. He discovered the famous natural moisturizing factor, made up of low molecular weight, water-soluble substances, dominantly amino acids, which are chiefly responsible for the ability of the stratum corneum to absorb water and to hold onto it in the face of a hostile dry environment.8 He went on to show that an extract of the natural moisturizing factor could ameliorate dry skin. 

The lack of filaggrin and keratohyaline in IV horny layer results in a deficiency of the natural moisturizing factor (NMF) — composed of urocanic acid and pyrrolidone carboxylic acid (PCA) — that is, breakdown products of amino acids in profilaggrin.12 In XRI, on the other hand, there is... 

Q Effects of Natural Moisturizing Factor and Lactic Acid Isomers on Skin Function... 

NATURAL MOISTURIZING FACTOR 18.2.1 The Role of the NMF in the Stratum Corneum... 

Urea is a physiological substance occurring in human tissues, blood, and urine. The amount in urine is of the order of 2%. The extraction of pure urea from urine was first accomplished by Proust in 1821, and it was first synthesized by Wohler in 1828.1 Urea is also a major constituent of the water-soluble fraction of the stratum corneum, as a component of the natural moisturizing factor (NMF).2 The level of urea in the stratum corenum is significantly reduced in patients with atopic dermatitis.3... 

Natural moisturizing factor (NMF) this comprises amino acids -I- hexoses -I- urea -I- aspartic acid -I- hexyl-nicotinate... 

Laden K. Natural moisturizing factors in skin. Am Perfum Cosmet 1967 82(10) 77-79. 

Hygroplex HHG. [Henkel/Cospha] Natural moisturizing factors in hydro-phOlic medium for emulsified aq. and hydroalcoholic skin mt tuiizing cosmetics. 

Table 2.2.6 Components of Sebum and Its Natural Moisturing Factor...

Water in the SC is necessary to maintain its pliability, elasticity, extensibility and resistance to trauma (Rawlings et al. 1994 Cork 1997) and to control the function of several enzymes that control desmo-some degradation and the formation of natural moisturizing factors (NMF) (Rawlings et al. 1994). When water falls below 5-10 mg/ioo mg of the SC dry weight (Schurer et al. 1991 Thune 1996b), the SC loses suppleness and cracks easily (Rudikoff 1998), the process of desquamation is altered and, instead of the usual unicellular and invisible cell detachment, corneocytes are shed in large visible blocks (Spencer 1988 Marks 1997 Rudikoff 1998). 

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