Effects of adenosine 5′-monophosphate on epidermal turnover

Abstract

The structure and function of the epidermis is maintained by cell renewal based on epidermal turnover. Epidermal turnover is delayed by aging, and it is thought that the delay of the epidermal turnover is a cause of aging alternation of skin. The epidermal turnover is related to the energy metabolism of epidermal basal cells. Adenosine 5'-triphosphate (ATP) is needed for cell renewal: cell division, and adenosine 5'-monophosphate (AMP) increases the amount of intracellular ATP. These findings suggest that AMP accelerates the epidermal turnover delayed by aging. This study investigated whether AMP and adenosine 5'-monophosphate disodium salt (AMP2Na) accelerates the epidermal turnover. An effect of AMP2Na on cell proliferation was examined by our counting of keratinocytes. An effect of AMP2Na on cell cycle was examined by our counting of basal cells in DNA synthetic period of hairless rats. The effects of AMP2Na (or AMP) on the epidermal turnover were examined by our measuring stratum corneum transit time by use of guinea pigs, and by our measuring stratum corneum surface area by use of hairless rats and in a clinical pharmacological study. The AMP2Na showed two different profiles on the proliferation of primary cultured keratinocytes. At a low concentration it induced cell growth, whereas at a high concentration it inhibited cell growth. The number of basal cells in the DNA synthetic period of AMP2Na was significantly higher than that of the vehicle in hairless rats. The stratum corneum transit time of AMP2Na was significantly shorter than that of the vehicle in guinea pigs. The corneocyte surface area of emulsion containing AMP2Na was significantly smaller than that of the vehicle in volunteers. We conclude that AMP promotes the cell proliferation and the cell cycle progression of epidermal basal cells and accelerates epidermal turnover safely. In addition, AMP is useful for skin rejuvenation in dermatology and aesthetic dermatology.

Exposure to naphthalene induces naphthyl-keratin adducts in human epidermisin vitroandin vivo

“…Keratinocytes in the basal layer proliferate and start differentiating and migrating to the surface to form the stratum corneum, which takes approximately four weeks (Furukawa et al, 2008). The differentiating basal keratinocytes express various differentiation markers, including large amounts of keratin 1 (K1) and keratin 10 (K10) proteins (Schweizer et al, 1983; Eichner et al, 1986).…”

The utility of naphthyl-keratin adducts as biomarkers for jet-fuel exposure

“…Thus, the principal route of contact and exposure to naphthalene is expected to be dermal. The NKA in the skin are formed via metabolism in the suprabasal layer of the skin (Kang-Sickel et al 2010) and manifested after the processes of keratinocyte maturation, proliferation, differentiation, and migration to the surface of stratum corneum , which take approximately 28 days (Junqueira & Carneiro 2005; Furukawa et al 2008). Since each tape-strip removes approximately 1 layer of stratum corneum (i.e.…”

“…Naphthalene metabolites bound to skin keratins would be appropriate as specific biomarkers for dermal exposure, as the bioactivation required for naphthalene metabolite adduction to keratin only occurs in the suprabasal layer of the epidermis (Kang-Sickel et al 2008; Kang-Sickel et al 2010), where keratin is synthesized de novo and the non-living squame is formed (Watt 1988). Approximately 20–28 days are required for differentiation and maturation of suprabasal keratinocytes (Junqueira & Carneiro 2005; Furukawa et al 2008) to migrate from the basal layer to the surface to form the stratum corneum , which requires continuous replacement. Therefore, non-invasive sampling of stratum corneum by sequential tape-stripping can be used to monitor an individual’s past (< 28 days) exposure to naphthalene-containing mixtures and characterize individual variation in dermal metabolic capacity and keratin adduction in human populations.…”

Whitening efficacy of plant extracts including orchid extracts on Japanese female skin with melasma and lentigo senilis

“…The whitening efficacy of plant extracts was evident as well as vitamin C derivative, as a quasi‐drug, in several aspects of the evaluations even in the aging skin. As mentioned above, formulation A contained a small amount of smoothing and rejuvenating ingredients 34–36 in addition to the plant extracts. Orchid‐rich plant extracts may show a synergistic effect with these agents leading to the impressive whitening efficacy of formulation A.…”