Expression of differential genes involved in the maintenance of water balance in human skin by Piptadenia colubrina extract.

BACKGROUND: Hydration and integrity of the stratum corneum (SC) is an important determinant of skin appearance, metabolism, mechanical properties, and barrier function. The presence of aquaglyceroporins and envelope proteins are crucial to provide greater corneocyte cohesion to keep water and other moisturizers in the skin. AIMS: In this study, we evaluated the ability of Piptadenia colubrina, a plant native of South American rain forests, in the expression of genes involved in skin capacitance and SC integrity. METHODS: The expression of genes for aquaporin-3 (AQP3), loricrin, involucrin (INV), and filaggrin (FLG) was measured by real-time PCR, using an in vitro model of human keratinocytes incubated with concentrations of 2.5, 5, 10, and 20 mg/mL of a hydroglycolic extract of P. colubrina (HEPC). The amount of AQP3 protein was also tested by immunohistochemistry in human skin explants. Clinical trials were conducted to evaluate the effects of a gel-cream containing HEPC on the glycerol index and skin capacitance. RESULTS: Hydroglycolic extract of P. colubrina increased both the expression and immunoreactivity of AQP3 in cultured keratinocytes and human skin explants. The gene induction to envelope proteins FLG and INV was also observed after cell incubation with HEPC. Skin capacitance was significantly improved in human volunteers under treatment with HEPC-containing cream. CONCLUSIONS: The extract of P. colubrina promotes cellular hydration and induces gene expression of envelope proteins providing greater corneocyte cohesion to keep water and other moisturizers in the skin and an appropriate epidermal adhesion. The in vitro findings were clinically confirmed and encourage the clinical use of this compound in skin care products.

Effect of green Coffea arabica L. seed oil on extracellular matrix components and water-channel expression in in vitro and ex vivo human skin models.

BACKGROUND: Green Coffea arabica L. seed oil is being widely used in cosmetic formulations, although its effects on human skin cells are not clear and most observations are unpublished. AIMS: In this study, we evaluated the in vitro effects of green coffee (C. arabica L.) oil (GCO) on the synthesis of collagen, elastin, and glycosaminoglycans (GAG) and in the release of transforming growth factor-beta1 (TGF-beta1) and granulocyte-macrophage colony-stimulating factor (GM-CSF) by human skin fibroblasts. We also investigated the ability of GCO to increase aquaglycerolporins-3 (AQP-3) mRNA expression in cultured keratinocytes and human skin explants. METHODS: Human fibroblasts were incubated for 48 h with several GCO concentrations (3.12, 6.25, 12.5, 25.0 and 50.0 mg/mL). The levels of growth factors and extracellular matrix compounds in the culture supernatant were measured using commercial kits. To evaluate AQP-3 relative expression, using real-time reverse transcription polymerase chain reaction, keratinocytes were incubated for 3-6 h with the GCO optimal concentration of 25.0 mg/mL. Histological sections of human skin were also incubated with GCO (25.0 mg/mL) and immunostained by antiserum against AQP-3. RESULTS: Our results demonstrated that incubation with GCO produces a dose-dependent stimulation in the synthesis of collagen, elastin, and GAG, in addition to increasing the release of the growth factors TGF-beta1 and GM-CSF. GCO also induced the expression of AQP-3 mRNA, which reached levels up to 6.5-fold higher than those of the control cultures. CONCLUSION: The findings presented herein suggest that GCO might improve physiological balance in the skin, thus allowing the formation of new connective tissue, and preventing epidermis dryness by increasing AQP-3 levels. Taking into account the limitations of in vitro studies, it is encouraging in this context to consider CGO as an adjuvant to be used in dermocosmetic formulations. Clinical studies are in progress in our laboratory aiming to further investigate the protective effects of CGO in the skin.

Relievene® SK: neuroimunomodulação para o tratamento dermocosmético da pele sensível / Relievene® SK: neuroimunomodulation for dermocosmetic treatment of sensitive skin

Pele sensível (PS) é definida como uma condição de tolerância reduzida ao uso freqüente ou prolongado de cosméticos e produtos de higiene pessoal, que apresenta desde sinais clínicos visíveis, como eritema, edema e descamação, até sinais neurossensoriais subjetivos de desconforto, como pinicamento, queimação, prurido, ressecamento e dor. A fisiopatologia da PS consiste em reação inflamatória decorrente de uma disfunção da barreira cutânea associada ao desequilíbrio da resposta neuroimunoendocrinológica da pele. Neste trabalho demonstramos os efeitos do produto Relievene® SK sobre a proteção do metabolismo celular, considerando as atividades adaptógena e neuroendócrina deste composto, bem como a melhora da função da barreira cutânea e da hiper-reatividade da pele em indivíduos com PS.

Neuroimmunomodulatory compound for sensitive skin care: in vitro and clinical assessment.

BACKGROUND: The pathophysiology of sensitive skin consists of an inflammatory reaction resulting from the abnormal penetration in the skin of potentially irritating substances, which occurs due to skin barrier dysfunction and changes in the production of local neuromediators. AIMS: The therapeutic potential of L-carnosine and Rhodiola rosea, as antioxidant and neuromodulatory, respectively, leads us to investigate the effects of the R. rosea extract/L-carnosine-associated compound (RCAC) on sensitive skin alterations. METHODS: A double-blind comparative study was conducted on 124 volunteers with sensitive skin, who were selected by their reactivity to stinging test. Two randomized groups of 62 each received either a formulation containing 1% of RCAC or placebo, which was applied twice a day for 28 consecutive days. One perceptibility questionnaire was applied at the onset and at the end of the treatment to evaluate the subjective response to test product. Additionally, in vitro studies were performed to investigate RCAC neuroimmunomodulatory mechanisms. RESULTS: RCAC treatment produced in vivo protective effects in skin barrier function and a positive subjective response of sensitive skin volunteers. In vitro treatment promoted the release of proopiomelanocortin peptides and restored to normal the increased levels of neuropeptides and cytokines produced by keratinocytes exposed to ultraviolet radiation. Clinical effectiveness was measured by reduction of transepidermal water loss, positive perceptions of improvements in skin dryness and skin comfort sensation, and reduction of discomfort sensation after stinging test. CONCLUSIONS: The protective effect of RCAC in skin barrier function and the positive response produced in human subjects with sensitive skin could be partially explained by our in vitro results showing a significant increase in opioid peptides release, an inhibitory effect on neuropeptides production, and modulation of cytokines production by keratinocytes under ultraviolet stress.