licochalcone-a and Erythema

More than 50% of adults report to suffer from sensitive skin. This common condition is characterized by subjective sensations such as prickling, burning, skin tightness or pruritus, and is often accompanied by objective symptoms like inflammation and erythema.. The objective of this study was to develop an active ingredient concept for the treatment of sensitive skin. We tested compounds regarding their potential to (i) decrease the release of proinflammatory mediators, which among others induce erythema and (ii) counteract the hyperresponsiveness of nerve fibres and, thus, exert effects on cutaneous neurosensory dysfunction.. 4-t-butylcyclohexanol, licochalcone A and acetyl dipeptide-1 cetyl ester were analysed in vitro regarding their potential to (i) decrease the release of PGE2 and activation of NFκB and to (ii) inhibit TRPV1 activation or the release of neuronal CGRP. To assess subjective and objective symptoms of skin sensitivity in vivo, two controlled, single-blind, randomized studies were conducted with 4-t-butylcyclohexanol and the combination with licochalcone A.. In vitro, 4-t-butylcyclohexanol significantly reduced TRPV1 activation, while acetyl dipeptide-1 cetyl ester had no effect on receptor activation. Licochalcone A significantly decreased NFκB signalling and PGE2 secretion, at lower concentrations than acetyl dipeptide-1 cetyl ester. A formulation containing 4-t-butylcyclohexanol showed a significant immediate anti-stinging/anti-burning effect in vivo, and a cream base containing a combination of 4-t-butylcyclohexanol and a licochalcone A-rich licorice extract reduced shaving-induced erythema.. In vitro and in vivo data indicate that the combination of the TRPV1 antagonist 4-t-butylcyclohexanol and the potent anti-inflammatory licochalcone A provide an effective active ingredient concept for the treatment of sensitive skin, as the topical application resulted in an immediate relief from symptoms such as erythema and stinging.

Topics: Adult; Animals; Anti-Inflammatory Agents, Non-Steroidal; Calcitonin Gene-Related Peptide; Capsaicin; Cell Line; Chalcones; Cyclohexanols; Dinoprostone; Dipeptides; Dose-Response Relationship, Drug; Drug Combinations; Erythema; Facial Dermatoses; Female; Humans; Male; Middle Aged; Neurons; NF-kappa B; Pain; Sensation Disorders; Signal Transduction; Single-Blind Method; Skin Cream; Swine; TRPV Cation Channels; Young Adult

Licochalcone A (LicA), a major phenolic constituent of the licorice species Glycyrrhiza inflata, has recently been reported to have anti-inflammatory as well as anti-microbial effects. These anti-inflammatory properties might be exploited for topical applications of LicA. We conducted prospective randomized vehicle-controlled clinical trials to assess the anti-irritative efficacy of cosmetic formulations containing LicA in a post-shaving skin irritation model and on UV-induced erythema formation. The clinical trials were accompanied by a series of in vitro experiments to characterize anti-inflammatory properties of LicA on several dermatologically relevant cell types. Topical LicA causes a highly significant reduction in erythema relative to the vehicle control in both the shave- and UV-induced erythema tests, demonstrating the anti-irritative properties of LicA. Furthermore, LicA is a potent inhibitor of pro-inflammatory in vitro responses, including N-formyl-MET-LEU-PHE (fMLP)- or zymosan-induced oxidative burst of granulocytes, UVB-induced PGE(2) release by keratinocytes, lipopolysaccharide (LPS)-induced PGE(2) release by adult dermal fibroblasts, fMLP-induced LTB(4) release by granulocytes, and LPS-induced IL-6/TNF-alpha secretion by monocyte-derived dendritic cells. The reported data suggest therapeutic skin care benefits from LicA when applied to sensitive or irritated skin.

Topics: Administration, Topical; Adult; Anti-Inflammatory Agents; Cells, Cultured; Chalcones; Dinoprostone; Erythema; Granulocytes; Humans; Interleukin-6; Keratinocytes; Leukotriene B4; Middle Aged; Plant Extracts; Prospective Studies; Respiratory Burst; Tumor Necrosis Factor-alpha; Ultraviolet Rays; Zymosan

Patients with rosacea and red facial skin often show sensitivity to skin care products which can exacerbate inflammation and subjective irritation. Besides pharmacologic management, special skin care is prudent to avoid cosmetically induced irritation and address cosmetic concerns. Appropriate skin care should provide gentle cleansing, UVA/UVB protection, effective moisturization, and concealing pigments to neutralize the appearance of redness.. To evaluate skin compatibility and efficacy of a skin care regimen containing licochalcone A (Lic A), an anti-irritant from the licorice plant Glycyrrhiza inflata, for subjects with mild to moderate facial redness.. Sixty-two patients with mild to moderate red facial skin used a four-product skin care regimen for 8 weeks. Clinical assessments of erythema and subjective irritation, cross-polarized photography, and self-assessment questionnaires were completed at baseline, and after 4 and 8 weeks of use. A quality of life questionnaire was given at baseline and week 8.. Clinical evaluations, subject response, and photography confirmed very good tolerability of the regimen and effective neutralization of redness by the pigmented products. Significant improvements in average erythema scores were observed at 4 and 8 weeks (P < 0.05), and an improvement in quality of life was confirmed by the patient questionnaires.. The skin care regimen containing Lic A was found to be compatible with the sensitive facial skin of patients with rosacea and improved the appearance of persistent facial redness. The products were also observed to be compatible with daily metronidazole treatment.

Topics: Adult; Aged; Chalcones; Drug Therapy, Combination; Erythema; Face; Female; Humans; Male; Metronidazole; Middle Aged; Quality of Life; Rosacea; Skin Care; Treatment Outcome

Patients with rosacea often show facial sensitivity to cosmetics or skin care products that can influence the severity of symptoms and exacerbate erythema and inflammation. Nevertheless, special skin care is necessary to address cosmetic concerns and reduce the potential side-effects of topical or oral treatment of the disease. Appropriate skin care should comprise gentle cleansing, effective moisturization, soothing actives, UV protection and concealing pigments to help neutralize the appearance of redness.. To determine the compatibility and efficacy of a skin care regimen (consisting of a cleanser, a day care with SPF25 and a night care) containing licochalcone A (Lic A), an anti-irritant from the licorice plant Glycyrrhiza inflata, and 4-t-butylcyclohexanol (SymSitive(®) ), a substance which acts as a sensitivity regulator, in female subjects with clinically determined subtype I rosacea.. Thirty-two test subjects with mild to moderate rosacea used the skin care regimen daily for 8 weeks. Clinical assessment of erythema, subjective irritation and clinical photography were performed at baseline and after 4 and 8 weeks. Additionally, a quality-of-life questionnaire was filled out by the test subjects at baseline and week 8. The subjects completed a self-assessment questionnaire on product properties after 4 and 8 weeks of product use.. Clinical assessments and subject response confirmed very good tolerability of the regimen, a statistically significant improvement in clinical grading for erythema and tactile roughness at weeks 4 and 8 and on telangiectasia at week 8 when compared to baseline scores. A statistically significant improvement in facial redness (a*) values, based on the L*a*b* colorimetric system, was determined at week 4 and 8 in comparison to baseline. No difference in corneometric measurement was detected at week 4 and 8 compared to baseline.. The skin care regimen was found to be highly compatible with the sensitive facial skin of patients with rosacea subtype I and effective in improving signs of rosacea. Therefore, the daily use of skin care products containing LicA and SymSitive(®) in patients with rosacea improves the overall skin appearance and the quality of life of these patients.

Topics: Adult; Anti-Inflammatory Agents, Non-Steroidal; Chalcones; Cyclohexanols; Detergents; Drug Therapy, Combination; Erythema; Female; Humans; Middle Aged; Quality of Life; Rosacea; Severity of Illness Index; Skin Care; Skin Cream; Sunscreening Agents; Surveys and Questionnaires; Telangiectasis; TRPV Cation Channels; Young Adult