[Methotrexate-associated photosensitization]. / Photosensibilisierung durch Methotrexat.

BACKGROUND: Methotrexate (MTX), alongside fumaric acid esters, is the most commonly used drug in the systemic therapy of psoriasis in Germany. It is sometimes used in combination with topical therapy and/or phototherapy due to synergistic effects. CASE REPORT: Here we describe a case of phototoxic dermatitis during treatment with MTX. Other cutaneous side effects of MTX include so-called UV recall, radiation recall, and skin tumor formation.

Antimicrobial activity against bacteria with dermatological relevance and skin tolerance of the essential oil from Coriandrum sativum L. fruits.

The aim of this work was to determine the antibacterial activity of essential coriander oil (ECO) on bacteria with dermatological relevance and to assess the skin tolerance of antimicrobial effective ECO concentrations. Essential coriander oil was tested on clinical isolates of different bacteria species, all of which may cause superficial skin infections. Antimicrobial susceptibility testing was performed using a standardized macrodilution test. Essential coriander oil showed good antibacterial activity towards the majority of the bacterial strains tested, including Streptococcus pyogenes (Lancefield group A) and methicillin resistant Staphylococcus aureus (MRSA), with mean minimal inhibitory concentrations of 0.04% v/v and 0.25% v/v, respectively. The skin tolerance of a cream and a lotion containing 0.5% and 1.0% ECO was assessed in 40 healthy volunteers using the occlusive patch test. No skin irritation could be observed by sensitive photometric assessment in any of the volunteers. Because of its activity against Streptococcus pyogenes, Staphylococcus aureus and MRSA combined with excellent skin tolerance, ECO might be useful as an antiseptic for the prevention and treatment of skin infections with Gram-positive bacteria.

Dermocosmetics for dry skin: a new role for botanical extracts.

Dry skin is associated with a disturbed skin barrier and reduced formation of epidermal proteins and lipids. During recent years, skin-barrier-reinforcing properties of some botanical compounds have been described. Searching the PubMed database revealed 9 botanical extracts that specifically improve skin barrier and/or promote keratinocyte differentiation in vivo after topical application. The topical application of Aloe vera (leaf gel), Betula alba (birch bark extract), Helianthus annuus (sunflower oleodistillate), Hypericum perforatum (St. John's wort extract), Lithospermum erythrorhizon (root extract), Piptadenia colubrina (angico-branco extract) and Simarouba amara (bitter wood extract) increased skin hydration, reduced the transepidermal water loss, or promoted keratinocyte differentiation in humans in vivo. The topical application of Rubia cordifolia root extract and rose oil obtained from Rosa spp. flowers stimulated keratinocyte differentiation in mouse models. The underlying mechanisms of these effects are discussed. It is concluded that some botanical compounds display skin-barrier-reinforcing properties that may be used in dermocosmetics for dry skin. However, more investigations on the mode of action and more vehicle-controlled studies are required.

Topical application of solubilized Reseda luteola extract reduces ultraviolet B-induced inflammation in vivo.

We investigated the skin tolerance and anti-inflammatory potential of a nanoparticular solubilisate of a luteolin-rich Reseda extract (s-RE) in two independent studies in vivo. Reseda luteola extract containing 40% flavonoids was solubilized with polysorbate, resulting in product micelles with a diameter of 10 (+/-1.5)nm. Standardized inflammation was induced by irradiating test areas on the back of healthy volunteers with defined doses of ultraviolet B (UVB). In the first study different concentrations of s-RE were tested in 10 volunteers to evaluate dose-dependency of anti-inflammatory effects of s-RE. In the second randomized, double-blind, placebo-controlled study a defined concentration of s-RE (2.5%w/w) was tested in 40 volunteers in comparison to the vehicle (glycerol) and hydrocortisone (1%w/w). s-RE dose-dependently reduced UVB-induced erythema when applied 30 min before irradiation. To a lesser extent, topical application of s-RE after irradiation also reduced UVB-induced erythema. s-RE was as effective as hydrocortisone, whereas the vehicle had no effect. Occlusive application of s-RE on non-irradiated test sites did not cause any skin irritation. Due to excellent skin tolerance combined with potent anti-inflammatory properties s-RE bears potential especially for the prevention but also for the treatment of inflammatory skin conditions such as UV-induced erythema.