Effects of golden tomato extract on skin appearance-outlook into gene expression in cultured dermal fibroblasts and on trans-epidermal water loss and skin barrier in human subjects.

SCOPE: Two experiments were performed to test the effects of rich tomato extract (Golden Tomato Extract, GTE) on human skin. In one experiment, the effects of this extract on gene expression in cultured human dermal fibroblasts were examined. In a second experiment, human subjects consumed the extract and trans-epidermal water loss (TEWL), and aspects of skin appearance were monitored. METHODS AND RESULTS: Primary human dermal fibroblasts in culture were treated with the extract. After six hours, RNA was extracted, and gene expression was examined using Affymetrix Human Clariom D array processing. For the clinical study, 65 human subjects consumed a capsule once a day for 16 weeks, and various skin parameters were assessed at predetermined time intervals. Among the genes upregulated by GTE are genes that augment innate immunity, enhance DNA repair, and the ability to detoxify xenobiotics. GTE significantly reduced TEWL in subjects who had high TEWL at baseline, but it had no effect on TEWL in subjects who had lower TEWL at baseline. CONCLUSIONS: Golden tomato extract may provide benefits to the skin by enhancing innate immunity and other defense mechanisms in the dermis and by providing antioxidants to the skin surface to optimize TEWL and the appearance of the skin.

A look at emerging delivery systems for topical drug products.

The introduction of new topical drugs based on new chemical entities has become a rare event. Instead, pharmaceutical companies have been focused on reformulating existing drugs resulting in an ever-growing number of topical drug products for every approved drug substance. In light of this trend, soon reformulations may not be as rewarding to their sponsors as they are today unless they offer a substantial improvement over other formulations of the same drug substance and the same indication, namely improved efficacy over existing drugs, reduced side effects, unique drug combinations, or applicability for new indications. This article reviews and compares topical drug delivery systems currently under active research that are designed to offer such advantages in the coming years. The reviewed delivery systems are: liposomes, niosomes, transferosomes, ethosomes, solid lipid nanoparticles, nanostructured lipid carriers, cyclodextrin, and sol-gel microcapsules. Among all the topical drug delivery systems currently undergoing active research, only the sol-gel microencapsulation is at clinical stages.

Skin moisturization by hydrogenated polyisobutene--quantitative and visual evaluation.

Hydrogenated polyisobutene (HP) is used in topically applied cosmetic/personal care formulations as an emollient that leaves a pleasing skin feel when applied, and rubbed in after application. This effect, although distinguishable to the user, is difficult to define and quantify. Recognizing that some of the physical properties of HP such as film formation and wear resistance may contribute, in certain mechanisms, to skin moisturization, we designed a short-term pilot study to follow changes in skin moisturization. HP's incorporation into an o/w emulsion at 8% yielded increased viscosity and reduced emulsion droplet size as compared to the emollient ester CCT (capric/caprylic triglyceride) or a control formulation. Quantitative data indicate that application of the o/w emulsion formulation containing either HP or CCT significantly elevated skin moisture content and thus reduced transepidermal water loss (TEWL) by a maximal approximately 33% against the control formulation within 3 h and maintained this up to 6 h. Visual observation of skin treated with the HP-containing formulation showed fine texture and clear contrast as compared to the control or the CCT formulation, confirming this effect. As a result of increased hydration, skin conductivity, as measured in terms of corneometer values, was also elevated significantly by about tenfold as early as 20 min after HP or CCT application and was maintained throughout the test period. Throughout the test period the HP formulation was 5-10% more effective than the CCT formulation both in reduction of TEWL as well as in increased skin conductivity. Thus, compared to the emollient ester (CCT), HP showed a unique capability for long-lasting effect in retaining moisture and improving skin texture.

The stratum corneum: a double paradox.

The stratum corneum (SC) (i.e., the outermost layer of human skin) is a complex and paradoxical tissue composed of corneocytes and a matrix of intercellular lipids playing an essential role as the skin's protective barrier. The first paradox of SC is its dual nature. It is composed of nondividing (dead) cells embedded in a metabolically active (live) environment whose function is to protect the epidermis and to maintain its integrity. In order to do so, the SC uses various strategies, including enzymatic reactions, colonization by bacterial flora, immune signaling, antimicrobial lipids and peptides, low pH, antioxidants, and natural moisturizing factor(s). The second paradox is that although its biological function is essentially that of a physicochemical barrier, cosmetologists and pharmacists are actively exploring paths for penetration through the SC to allow passage of active molecules and their penetration into the skin. Various pathways of penetration and physicochemical factors facilitating this penetration into the dermis and/or the epidermis have been defined, but the exact mechanisms of penetration of cosmetic ingredients remain elusive. For cosmetologists and pharmacists, the SC represents a major focus of interest whether for basic research or the development of novel topical approaches taking into account the fascinating properties of this complex tissue.