Vom dermatologischen Gemüsegarten zur Ernährungslehre: Sigwald Bommer (1893 – 1963) zum 125. Geburtstag

Zusammenhänge zwischen Hautkrankheiten und Ernährung finden in neuerer Zeit wieder mehr Beachtung, zum Beispiel bei Psoriasis und Akne. Hingegen beschäftigten sich Ärzte aus den verschiedensten Fachbereichen in der ersten Hälfte des 20. Jahrhunderts eingehend mit der Ernährung als Einflussfaktor auf Gesundheit und Krankheit. So auch der wenig bekannte Dermatologe Sigwald Bommer (1893 – 1963), der Lehrstuhlinhaber an der Universität in Greifswald war. Hautkrankheiten nicht nur lokal zu behandeln, sondern einen ganzheitlichen Ansatz zu verfolgen, lernte Bommer in der Lupusheilstätte Gießen bei Albert Jesionek (1870 – 1935), wo allgemeine Lichttherapie zum Einsatz kam. Dort begannen Diätversuche, die schwere Fälle von Hauttuberkulose, insbesondere Lupus vulgaris, zur Abheilung brachten. Dies hinterließ bei Bommer einen derartigen Eindruck, dass er sich seit dieser Zeit mit der Ernährungsbehandlung beschäftigte und sie zu einer vierstufigen Diättherapie weiterentwickelte. Über gewisse Variationen der Ernährungsstufen behandelte er unterschiedliche Hautkrankheiten wie Psoriasis, Rosazea, Ekzeme und Akne vulgaris mit Erfolg. Die Wirkung sah er in der Verbesserung der Durchblutungssituation bis in die Kapillaren, was er anhand von histologischem Material zu belegen versuchte. Weitere Beobachtungen überzeugten Bommer, dass neben Durchblutungs- auch Verdauungsstörungen bei den dermatologischen Patienten als häufige Komorbiditäten bestanden. Als zentralen Ansatzpunkt seiner Ernährungstherapie sah er das „System der inneren Atmung“, das heißt die Oxidations- und Reduktionssysteme im Zellstoffwechsel: Aufnahme einer gesunden und vollwertigen Nahrung verbesserte grundlegend die Verdauungstätigkeit, die kapillare Durchblutungssituation der Gewebe und damit auch den Stoffaustausch an der Zelle selbst.

A novel triterpene extract from mistletoe induces rapid apoptosis in murine B16.F10 melanoma cells

The European mistletoe Viscum album L. is a plant used for remedies in cancer treatment. The benefit of commonly used aqueous extracts is controversial but the plant contains water insoluble triterpene acids providing interesting anticancer properties. Triterpene extracts (TE) from plants and single triterpenoids such as oleanolic acid (OA) or betulinic acid (BA) are known for their cytotoxic effects on cancer cell lines in vitro. We report here cytotoxic effects of a novel OA-rich triterpene extract from mistletoe (V. album L., Santalaceae) solubilized by 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) on B16.F10 mouse melanoma cells. The 2-HP-β-CD solubilized triterpene extract (STE) was highly cytotoxic by causing DNA fragmentation, followed by loss of membrane integrity and intracellular adenosine-5'-triphosphate (ATP). Blocking the caspase machinery by inhibitors aborted DNA fragmentation and delayed the cytotoxic effects but did not prevent cell death. The solubilization by 2-HP-β-CD allows a solvent-free application of triterpene extracts in the in vitro setting. These findings suggest the use of STE from mistletoe as a solvent-free anticancer drug for preclinical animal experiments and clinical trials.

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.

Skin tolerance of a new bath oil containing St. John's wort extract

BACKGROUND

Dry and atopic skin requires skin care with lipid-rich emollients and moisturizing bath or shower oils. However, it has been shown recently that some bath oils may even impair the skin barrier.

OBJECTIVE

To investigate the skin-irritating potential of a new bath oil containing a lipophilic St. John's wort (Hypericum perforatum) extract.

METHODS

In this single-center, randomized, double-blind, prospective study, 3 bath oils together with positive and negative controls were applied under occlusion on test areas on the volar forearms of 18 volunteers (visit 1). After 24 h, the tapes were removed, and the test areas were evaluated by a visual score and the instrumental measurement of skin erythema and transepidermal water loss (TEWL) using a Mexameter and a Tewameter (visit 2). The test substances were applied a second time, and the measurements were performed after another 24 h (visit 3).

RESULTS

The positive control, 1% vol/vol sodium lauryl sulfate (SLS), caused a significant increase in skin erythema and TEWL. In contrast, distilled water as a negative control did not influence these parameters. The new bath oil containing St. John's wort extract and 1 of the other 2 commercial products were not different from the water control. The third bath oil displayed a skin-irritating effect similar to SLS.

CONCLUSION

The results of this study confirm the different skin-irritating potential of bath oils and demonstrate good skin tolerance of the new bath oil containing St. John's wort extract.

Usnea barbata extract prevents ultraviolet-B induced prostaglandin E2 synthesis and COX-2 expression in HaCaT keratinocytes

Usnea barbata and its major constituent usnic acid are potent antimicrobial agents. Here, we have investigated anti-inflammatory properties of an U. barbata extract (UBE) containing 4% usnic acid in an ultraviolet-B (UVB) model with HaCaT keratinocytes. UVB irradiation induced PGE(2) production and COX-2 expression in a time and dose-dependent manner. UBE inhibited PGE(2) production at a half-maximal concentration of 60 microg/ml (2.4 microg/ml usnic acid) that did not affect the UVB-induced upregulation of COX-2, suggesting an effect on enzyme activity rather than on protein expression. The inhibition of PGE(2) production by UBE was not due to cytotoxicity. Besides its known antimicrobial properties, UBE displays specific UVB protective effects that might be useful in the topical treatment of UVB-mediated inflammatory skin conditions.

Screening of plant extracts for antimicrobial activity against bacteria and yeasts with dermatological relevance

There is cumulative resistance against antibiotics of many bacteria. Therefore, the development of new antiseptics and antimicrobial agents for the treatment of skin infections is of increasing interest. We have screened six plant extracts and isolated compounds for antimicrobial effects on bacteria and yeasts with dermatological relevance. The following plant extracts have been tested: Gentiana lutea, Harpagophytum procumbens, Boswellia serrata (dry extracts), Usnea barbata, Rosmarinus officinalis and Salvia officinalis (supercritical carbon dioxide [CO2] extracts). Additionally, the following characteristic plant substances were tested: usnic acid, carnosol, carnosic acid, ursolic acid, oleanolic acid, harpagoside, boswellic acid and gentiopicroside. The extracts and compounds were tested against 29 aerobic and anaerobic bacteria and yeasts in the agar dilution test. U. barbata-extract and usnic acid were the most active compounds, especially in anaerobic bacteria. Usnea CO2-extract effectively inhibited the growth of several Gram-positive bacteria like Staphylococcus aureus (including methicillin-resistant strains - MRSA), Propionibacterium acnes and Corynebacterium species. Growth of the dimorphic yeast Malassezia furfur was also inhibited by Usnea-extract. Besides the Usnea-extract, Rosmarinus-, Salvia-, Boswellia- and Harpagophytum-extracts proved to be effective against a panel of bacteria. It is concluded that due to their antimicrobial effects some of the plant extracts may be used for the topical treatment of skin disorders like acne vulgaris and seborrhoic eczema.

Toxische Phytodermatitis nach Kontakt mit Euphorbia helioscopia L. (Sonnenwend-Wolfsmilch)

A 6-year-old patient presented with linear erythema and bullae on the face. The lesions developed after playing with plants the day before. The plant was identified as Euphorbia helioscopia L. (sun spurge). The sun spurge belongs to the Euphorbiaceae plant family. These plants produce a typical milky juice that causes toxic reactions following contact with skin and mucous membranes. In the literature several cases of toxic dermatitis caused by plants of the Euphorbiaeae family have been described. The most important differential diagnosis of these skin lesions is the bullous phototoxic dermatitis caused by psoralens. Plant-induced toxic dermatitis is of increasing importance in dermatology. The exact determination of the causative plants is a prerequisite for the diagnosis of phytodermatitis.

The UV Erythema Test as a Model to Investigate the Anti-Inflammatory Potency of Topical Preparations – Reevaluation and Optimization of the Method

BACKGROUND

The ultraviolet (UV) erythema test is one of the most frequently used methods to investigate the anti-inflammatory potency of topical dermatological preparations in vivo.

METHODS

The following questions were addressed in four separate studies with healthy persons (skin types 2 and 3): (1) the optimal localization was determined by comparing light scales on the back, buttocks and volar forearms; (2) the optimal UV-B dose was determined by comparing the 1-fold, 1.5-fold and 2-fold minimal erythema doses (MEDs); (3) hydrocortisone and prednicarbate were evaluated as positive controls, and a sample size calculation was performed, and (4) betamethasone valerate and pimecrolimus were tested as further positive controls in the optimized study model.

RESULTS

The back proved to be the best localization for the UV erythema test. It showed a good correlation between the light scale and the test areas. The 1.5-fold MED was the best irradiation dose. In contrast to prednicarbate and betamethasone valerate, hydrocortisone was a rather weak positive control. However, when the sample size was > or = 40 subjects, significant results were also obtained with hydrocortisone. Pimecrolimus was not effective in the UV erythema test.

CONCLUSIONS

The UV erythema test should be performed on the back with at least 40 subjects using the 1.5-fold MED. It may be useful to include a potent corticosteroid, such as prednicarbate or betamethasone valerate, in addition to hydrocortisone. The UV erythema test seems to be suitable only for substances with corticosteroid-like effects, since in this test model the calcineurin inhibitor pimecrolimus was not effective.

[Topical treatment of atopic dermatitis with Hypericum cream. A randomised, placebo-controlled, double-blind half-side comparison study]

BACKGROUND

Recent investigations suggest an anti-inflammatory and antibacterial effect of hyperforin, which is a major constituent of Hypericum perforatum L. (Saint John's wort).

OBJECTIVE

In a half-side comparison study we assessed the efficacy of a cream containing Hypericum extract standardized to 1.5% hyperforin (verum) in comparison to the corresponding vehicle (placebo) for the treatment of subacute atopic dermatitis. The study design was a prospective randomized placebo-controlled double-blind single center study.

METHODS

In twenty one patients suffering from mild to moderate atopic dermatitis (mean SCORAD 44.5) the treatment with verum or placebo was randomly allocated to the left or right site of the body, respectively. The patients were treated twice daily over a period of four weeks. Eighteen patients completed the study. The severity of the skin lesions on the left and right site was determined by means of a modified SCORAD-index (primary endpoint).

RESULTS

The intensity of the eczematous lesions improved on both sites of treatment. However, the Hypericum cream was significantly superior to the vehicle at all clinical visits (days 7, 14, 28) (p<0.05). Skin colonization with Staphylococcus aureus was reduced by both verum and placebo, showing a trend to better antibacterial activity of the Hypericum cream (p=0.064). Skin tolerance and cosmetic acceptability was good or excellent with both the Hypericum cream and the vehicle (secondary endpoints).

CONCLUSION

Hypericum cream was significantly superior to its vehicle in the topical treatment of mild to moderate atopic dermatitis. The therapeutic efficacy of the Hypericum cream should be evaluated in further studies with larger patient cohorts, in comparison to standard therapeutic agents (i.e. corticosteroids).

[St. John's wort (Hypericum perforatum L.). A plant with relevance for dermatology]

Saint John's wort (Hypericum perforatum L.) is a herbal remedy that is effective in the treatment of mild to moderate depression. In traditional folk medicine, oily extracts of St. John's wort are used for topical treatment of wounds, burns and myalgia. The lipophilic phloroglucin-derivative hyperforin has antibacterial and antiinflammatory effects. These effects could be of relevance in topical treatment of infected wounds and other dermatoses, but no studies have been conducted so far. The naphtodianthrone hypericin is a photodtodynamic active substance that kills tumor cells via the induction of apoptosis. Hypericin also displays antiviral activity in vitro. In vivo, intravenous or oral treatment with hypericin of HIV-infected subjects did not result in a reduction of the virus load. Most of the patients treated with hypericin experienced phototoxicity. Similar phototoxic symptoms ("hypericism") have been observed in grazing animals ingesting large amounts of St. John's wort. In contrast, antidepressant medication with St. John's wort usually does not produce phototoxic symptoms. Recent pharmacokinetic studies suggest that the phototoxic threshold level of hypericin is not reached with dosages used for the oral treatment of depression. However, very recent reports demonstrated interactions of St. John's wort with other drugs such as digoxin, indinavir and cyclosporin. Blood levels of these drugs were dramatically decreased by St. John's wort. This should be considered in the treatment of skin conditions with antiviral drugs or cyclosporin.

[Plant-induced toxic and allergic dermatitis (phytodermatitis)]

Herbal products are being used increasingly for medical or cosmetic purposes. Many cosmetics contain plant extracts for fragrance. Sensitizing plants in cosmetics are tea tree oil, arnica, chamomile, yarrow, citrus extracts, common ivy, aloe, lavender, peppermint, and others. However, the sensitizing potential of these plants varies. Most of the sensitizing substances are sesquiterpene lactones or terpenes. The present paper reviews the various forms of phytodermatitis, including irritant plant dermatitis, phototoxic and photo-allergic dermatitis, allergic dermatitis, and airborne contact dermatitis.

Soluble CD44 inhibits melanoma tumor growth by blocking cell surface CD44 binding to hyaluronic acid

Proteolytic cleavage of the extracellular domain of CD44 from the surface of cells has been observed recently in different cell types. In cell culture supernatants of human melanoma cell lines a 70 kDa soluble CD44 protein (solCD44) was detected at concentrations of 250-300 ng/ml. Protease inhibitor studies revealed that serine proteases and metalloproteases are involved in the cleavage of CD44 from the surface of melanoma cells. To analyse a possible function of soluble CD44 a human malignant melanoma cell line was stably transfected with cDNAs encoding either wild type soluble CD44s or mutated forms with defective HA binding properties (CD44sR41A and CD44sR150A/R154A). Soluble CD44s almost completely inhibited hyaluronic acid binding by melanoma cells, whereas soluble CD44 mutated in the HA binding domain had no effect. When cultivated on hyaluronic acid, melanoma cell proliferation was induced by 30% for both the parental and the control transfected cells. This increase in proliferation was blocked completely in solCD44s-secreting transfectants, whereas solCD44sR41A and solCD44sR150A/R154A-secreting cells again showed hyaluronic acid-induced cell proliferation. These cell lines were subcutaneously injected into MF1 nu/nu mice to compare their growth as tumors in vivo. Compared to tumors derived from parental and control transfected cells, we observed a dramatic reduction of primary tumor growth with solCD44s expressing MM cells. Transfectants expressing solCD44s mutated in the HA binding domain in contrast developed fast-growing primary tumors. These results provide strong evidence that direct solCD44 interactions with hyaluronic acid interfere competitively with processes induced by hyaluronic acid binding to surface CD44. Autocrine, or drug-induced secretion of solCD44 by human melanoma cells may thus exert potent antitumoral effects in vivo.

Hypericin photo-induced apoptosis involves the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and activation of caspase-8

Hypericin (HYP) is a photosensitizing pigment from Hypericum perforatum that displays cytotoxic effects in neoplastic cell lines. Therefore, HYP is presently under consideration as a new anticancer drug in photodynamic therapy. Here, we investigated the mechanism of action of HYP photo-induced apoptosis of Jurkat cells compared to the cytostatic drug paclitaxel (PXL). Both photoactivated HYP and PXL similarly increased the activity of caspase-8 and caspase-3, and drug-induced apoptosis of Jurkat cells was completely blocked by inhibitors of caspase-8 (Z-IETD-FMK) and caspase-3 (Z-DEVD-FMK). The involvement of death receptors was analyzed using neutralizing monoclonal antibodies against Fas (SM1/23), FasL (NOK-2) and TNF-R1 (MAB225), and a polyclonal rabbit anti-human TNF-related apoptosis-inducing ligand (TRAIL) antiserum. TRAIL antibody blocked TRAIL-induced and HYP photo-induced, but not PXL-induced apoptosis of Jurkat cells. In contrast, PXL-induced, but not HYP-induced apoptosis was blocked by the SM1/23 and NOK-2 antibodies. Anti-TNF-R1 antibody had no effect. These findings suggest that HYP photo-induced apoptosis of Jurkat cells is mediated in part by the TRAIL/TRAIL-receptor system and subsequent activation of upstream caspases.

Magnesium ions inhibit the antigen-presenting function of human epidermal Langerhans cells in vivo and in vitro. Involvement of ATPase, HLA-DR, B7 molecules, and cytokines

The combination of seawater baths and solar radiation at the Dead Sea is known as an effective treatment for patients with psoriasis and atopic dermatitis. Dead Sea water is particularly rich in magnesium ions. In this study we wished to determine the effects of magnesium ions on the capacity of human epidermal Langerhans cells to stimulate the proliferation of alloreactive T cells. Twelve subjects were exposed on four subsequent days on the volar aspects of their forearms to 5% MgCl2, 5% NaCl, ultraviolet B (1 minimal erythemal dose), MgCl2 + ultraviolet B, and NaCl + ultraviolet B. Epidermal sheets were prepared from punch biopsies and were stained for ATPase and HLA-DR. Compared with untreated skin, the number of ATPase+/HLA-DR+ Langerhans cells was significantly reduced after treatment with MgCl2 (p = 0.0063) or ultraviolet B (p = 0.0005), but not after NaCl (p = 0.7744). We next questioned whether this reduced expression of ATPase and HLA-DR on Langerhans cells bears a functional relevance. Six subjects were treated on four subsequent days with 5% MgCl2, ultraviolet B (1 minimal erythemal dose), and MgCl2 + ultraviolet B. Epidermal cell suspensions from treated and untreated skin were assessed for their antigen-presenting capacity in a mixed epidermal lymphocyte reaction with allogeneic naive resting T cells as responder cells. Treatment with MgCl2, similarly to ultraviolet B, significantly reduced the capacity of epidermal cells to activate allogeneic T cells (p = 0.0356). Magnesium ions also suppressed Langerhans cells function when added to epidermal cell suspensions in vitro. The reduced antigen-presenting capacity of Langerhans cells after treatment with MgCl2 was associated with a reduced expression by Langerhans cells of HLA-DR and costimulatory B7 molecules, and with a suppression of the constitutive tumor necrosis factor-alpha production by epidermal cells in vitro. These findings demonstrate that magnesium ions specifically inhibit the antigen-presenting capacity of Langerhans cells and may thus contribute to the efficacy of Dead Sea water in the treatment of inflammatory skin diseases.

Effect of topical application of Hypericum perforatum extract (St. John's wort) on skin sensitivity to solar simulated radiation

St. John's wort (Hypericum perforatum) is a tradional folk remedy that is used for the topical treatment of superficial wounds, scars and burns. A characteristic metabolite of St. John's wort is the photodynamic active plant pigment hypericin. It is known that hypericin may cause a severe photodermatitis called hypericism when higher amounts of St. John's wort are ingested orally. To date, no reports on the photosensitizing capacity of topical application of St. John's wort are available. Here, we investigated the effects of Hypericum oil (hypericin 110 microg/mL) and Hypericum ointment (hypericin 30 microg/mL) on skin sensitivity to solar simulated radiation. Sixteen volunteers of the skin types II and III were tested on their volar forearms with solar simulated radiation for photosensitizing effects of Hypericum oil (n=8) and Hypericum ointment (n=8). The minimal erythema dose (MED) was determined by visual assessment, and skin erythema was evaluated photometrically. With the visual erythema score, no change of the MED could be detected after application of either Hypericum oil or Hypericum ointment (P>0.05). With the more sensitive photometric measurement, an increase of the erythema-index after treatment with the Hypericum oil could be detected (P< or =0.01). The results do not provide evidence for a severe phototoxic potential of Hypericum oil and Hypericum ointment, detectable by the clinically relevant visual erythema score. However, the trend towards increased photosensitivity detected with the more sensitive photometric measurement could become relevant in fair-skinned individuals, in diseased skin or after extended solar irradiation.

Topical application of St John's wort (Hypericum perforatum L.) and of its metabolite hyperforin inhibits the allostimulatory capacity of epidermal cells

St John's wort (Hypericum perforatum) is a traditional herbal medicine that is used for the topical treatment of superficial wounds, burns and dermatitis. The characteristic metabolites of St John's wort are the photodynamic active plant pigment hypericin and the phloroglucin-derivative hyperforin. To date, no studies on immunomodulatory properties of topical preparations of St John's wort have been performed. Here, we investigated the alloantigen presenting function of human epidermal cells (EC) exposed to Hypericum ointment in vivo in a mixed EC lymphocyte reaction (MECLR). The effect of Hypericum ointment was compared with the immunosuppressive effect of solar-simulated radiation (SSR). Subsequently, we tested purified hyperforin in vivo and in vitro in a MECLR to evaluate its possible contribution to the effect of the Hypericum ointment. Furthermore, we assessed the effect of hyperforin on the proliferation of peripheral blood mononuclear cells (PBMC) in vitro. Compared with untreated skin, treatment with Hypericum ointment resulted in a significant suppression of the MECLR (P </= 0.001) that was similar to the effect of SSR. The combination of Hypericum ointment plus SSR was not significantly different from either treatment alone. EC isolated from skin treated with the hyperforin containing ointment also showed a reduced capacity to stimulate the proliferation of allogeneic T cells (P </= 0.001). Similarly, in vitro incubation of EC with hyperforin suppressed the proliferation of alloreactive T cells (P </= 0.001). Furthermore, hyperforin inhibited the proliferation of PBMC in a dose-dependent manner, without displaying pronounced toxic effects as determined by Trypan blue staining. The results demonstrate an inhibitory effect of Hypericum extract and of its metabolite hyperforin on the MECLR and on the proliferation of T lymphocytes that may provide a rationale for the traditional treatment of inflammatory skin disorders with Hypericum extracts.

[Comparison of balneophototherapy and UVA/B mono-phototherapy in patients with subacute atopic dermatitis]

In a controlled prospective study we compared the efficacy of combined salt water bath and UVA/B phototherapy to a UVA/B mono-phototherapy in patients with subacute atopic dermatitis (AD). The patients in the balneophototherapy group (n=16) were treated with baths containing 3-5% of the synthetic salt Psori-sal(trade mark), followed immediately by UVA/B irradiation, while the other treatment arm (n=12) received UVA/B phototherapy alone. After 20 treatments the balneophototherapy group showed a statistically significant (p</=0.0015) reduction of the SCORAD score from 69.5 before to 36.8 after therapy. No statistically significant reduction in the SCORAD score could be observed in the UVA/B phototherapy group (50.6 before to 44.3 after therapy). The cumulative UVB dose was significantly lower in the balneophototherapy group (0.9 J/cm2) as compared to the UVA/B monotherapy group (2.0 J/cm2). Balneophototherapy was well tolerated by patients with atopic dermatitis and no side effects were observed. We conclude that balneophototherapy expands the therapeutic options for patients with subacute atopic dermatitis.

Hypericin levels in human serum and interstitial skin blister fluid after oral single-dose and steady-state administration of Hypericum perforatum extract (St. John's wort)

The photodynamically active plant pigment hypericin, a characteristic metabolite of Hypericum perforatum (St. John's wort), is widely used as an antidepressant. When administered orally, phototoxic symptoms may limit the therapeutic use of hypericin-containing drugs. Here we describe the high-performance liquid chromatographic (HPLC) detection of hypericin and semiquantitative detection of pseudohypericin in human serum and skin blister fluid after oral single-dose (1 x 6 tablets) or steady-state (3 x 1 tablet/day, for 7 days) administration of the Hypericum extract LI 160 in healthy volunteers (n = 12). Serum levels of hypericin and pseudohypericin were always significantly higher than skin levels (p </= 0.01). After oral single-dose administration of Hypericum extract the mean serum level of total hypericin (hypericin + pseudohypericin) was 43 ng/ml and the mean skin blister fluid level was 5.3 ng/ml. After steady-state administration the mean serum level of total hypericin was 12.5 ng/ml and the mean skin blister fluid level was 2.8 ng/ml. These skin levels are far below hypericin skin levels that are estimated to be phototoxic (>100 ng/ml).

[Bullous phototoxic contact dermatitis caused by Ruta graveolens L. (garden rue), Rutaceae. Case report and review of literature]

A patient developed severe bullous phototoxic contact dermatitis caused by Ruta graveolens L. (garden rue) which belongs to the Rutaceae family. To date only a few cases of phototoxic reactions to the garden rue have been reported. The phototoxic components of Ruta graveolens L. are the fouranocoumarins 5-methoxypsoralen (bergapten) and 8-methoxypsoralen (xanthotoxine), and the furanoquinoline dictamnine whose phototoxic properties were recently discovered. Since the garden rue is frequently cultivated, it should be considered in the differential diagnosis of phototoxic phytodermatitis.

Salt water bathing prior to UVB irradiation leads to a decrease of the minimal erythema dose and an increased erythema index without affecting skin pigmentation

The combination of salt water baths and solar radiation is known as an effective treatment for patients with psoriasis and atopic dermatitis. To determine whether increased susceptibility to UVB radiation may contribute to this therapeutic effect we have studied the effect of bathing the skin in salt water prior to UVB irradiation. Twelve subjects were phototested on the volar aspects of their forearms with increasing doses of UVB radiation. One forearm was exposed to 5% salt water prior to irradiation. The minimal erythema dose (MED) was determined and the erythema index and skin pigmentation were assessed by photometric measurement. The combination of salt water bath and irradiation yielded a significant decrease of the MED when compared to UVB alone (median 90 mJ/cm2 vs 130 mJ/cm2, P < 0.01). Analysis of variance showed a significant influence of salt water bath on erythema (P < 0.05) but not on skin pigmentation. Within the MED test area the erythema index of the salt water exposed forearms was elevated significantly (P < 0.05) while skin pigmentation was not affected. Thus, bathing the skin in salt water leads to a decreased threshold level for the elicitation of UVB-induced erythema and a selective increase of the erythemal response. This sensitization to the effects of shortwave UVB radiation may increase immunosuppressive effects of UVB radiation and may lead to an increased efficacy of UVB phototherapy. However, there is also an increased sunburn risk when salt water baths are followed by exposure to UV radiation.

In vitro and in vivo activation of hypericin with the incoherent light source PDT 1200 SOA (520-750 nm) and with solar simulated radiation (290-2500 nm)

The photodynamic active plant pigment hypericin is a possible new photosensitizer for photodynamic therapy. Hypericin shows absorption maxima in the ultraviolet (330 nm) and visible light range (550 and 588 nm). The present study compared the photoactivation of hypericin with the incoherent light source PDT 1200 SOA (520-750 nm) to that with a 1000 watt solar simulator (290-2500 nm). Hypericin displayed dose and time dependent phototoxic effects in the keratinocyte cell line HaCaT in vitro and after intracutaneous in vivo application with both light sources. In vivo, delayed (48 h) photosensitivity in hypericin-sensitized skin was observed. With intracutaneous application of 100 ng/ml hypericin, no phototoxic reaction could be produced. The PDT 1200 SOA was about four times more effective in vitro and about ten times more effective in vivo when compared to the solar simulator. Since the PDT 1200 SOA allows homogenous irradiation of large areas, we conclude that the PDT 1200 SOA is an effective and convenient light source for in vitro and in vivo studies using hypericin.

[Effect of various salt solutions on ultraviolet B-induced erythema and pigmentation]

The combination of saltwater baths and subsequent ultraviolet irradiation is an effective treatment for psoriasis and atopic dermatitis. The aim of the present study was to determine the photosensitizing properties of two commercially available bath salts, original salt from the Dead Sea and sodium chloride. To address this issue, test areas on the volar aspects of the forearms were soaked with salt solutions for 15 minutes prior to ultraviolet-B (UVB) irradiation. The salt concentrations tested were 1%, 3% 5% and 15%. Tap water followed by UVB and UVB alone served as controls. Erythema was determined by visual and photometric measurement, and delayed tanning was assessed by colorimetry. Erythema obtained by wetting the skin prior to UVB irradiation was more pronounced than erythema induced by UVB alone. The most prominent erythema was yielded by tap water + UVB. The salts had a differing photosensitizing capacity and the strongest erythema was produced by the 5% solutions. There was only a moderate influence on delayed tanning by bathing the skin prior to irradiation. The results from the present study indicate that soaking the skin with salt solutions or tap water increases skin sensitivity to subsequent UVB irradiation. This may contribute to the effectiveness of salt water baths followed by UV irradiation and may account for an increased sunburn risk after bathing.

Treatment of chronic palmoplantar eczema with local bath-PUVA therapy

BACKGROUND

Systemic PUVA therapy may be useful in the treatment of chronic palmoplantar eczema. Topical PUVA-paint avoids some of the unwanted side effects of systemic psoralens and has been used successfully in the treatment of palmoplantar eczema and psoriasis. However, few data are available on the effectiveness of local bath-PUVA therapy in palmoplantar eczema.

OBJECTIVE

Our purpose was to assess the effectiveness of local bath-PUVA therapy in 28 patients with chronic palmar or plantar eczema or both who were resistant to conventional topical treatment.

METHODS

After fungal or bacterial infection had been excluded in all patients, hands or feet or both were soaked for 15 minutes in warm water containing 1 mg/L 8-methoxypsoralen. Immediately after, the skin was irradiated with increasing doses of UVA, starting with 0.5 J/cm2. PUVA-bath therapy was performed 4 times a week up to a total of 25 treatments. No additional therapy was allowed except emollients.

RESULTS

Excellent or good effects were achieved in 93% of the patients with dyshidrotic and in 86% of the patients with hyperkeratotic eczema. In the patients with dyshidrotic eczema, the cumulative doses and the highest single doses of UVA were lower than those in the patients with hyperkeratotic eczema (21.4 vs 27.9 J/cm2 and 2.4 vs 3.0 J/cm2 of UVA), but this was not statistically significant. No phototoxic reactions were observed.

CONCLUSION

Local bath-PUVA therapy is of value in the management of chronic palmoplantar eczema resistant to standard modes of topical treatment. Compared with topical PUVA-paint, local bath-PUVA therapy has several advantages, particularly the absence of phototoxic reactions, severe hyperpigmentation, and protracted photosensitivity.

[Characterization of nonresponders in high dosage UVA1 therapy of acute exacerbated atopic dermatitis]

High-dose UVA1 therapy is an effective treatment of patients with acute atopic dermatitis. However, some patients do not respond well to this new therapy. We attempted to further characterize the non-responder population in a retrospective study. Two closely matched groups of responders (n = 20) and non-responders (n = 20) were compared. No significant differences were observed between both groups with respect to the following parameters: skin type, minimal erythema dose, single and cumulative doses of UVA1, and peripheral blood eosinophils. However, non-responders were characterized by a highly elevated atopic score, and by high levels of total IgE and of specific IgE. Furthermore, colonization of the skin with Staphylococcus aureus occurred at higher densities, and intestinal growth of Candida albicans was more frequently observed. These data indicate that high-dose UVA1 irradiation is not effective in all patients suffering from atopic dermatitis. We conclude that non-responders with complicating infections might benefit from the combination of high-dose UVA1 therapy and antibiotic or antimycotic treatment.

[Bath additives in dermatologic balneotherapy. Indications and approaches in current research]

Progress in dermatological research during the last years has provided new insights into the mode of action of additives to dermatological baths. The present paper reviews the pharmacokinetics of dermatological bath therapy additives such as sulfur, salts and trace elements, tars and ichthyol, lipids, antiseptics, astringents, plant extracts, surface-active agents and proteins.

[Dermatitis bullosa striata pratensis caused by Dictamnus albus L. (burning bush)]

We report two patients with bullous phototoxic contact dermatitis caused by Dictamnus albus L. (gas plant) which belongs to the Rutaceae family. In both cases long lasting postinflammatory hyper-pigmentations were observed as a result of the phototoxic contact dermatitis. The phototoxic components of Dictamnus albus L. are the furocoumarins 5-methoxypsoralen (bergapten) and 8-methoxypsoralen, and the alkaloid dictamnin whose phototoxic properties were recently discovered. Even though reactions to the gas plant have been infrequently reported, it is becoming more popular with gardenus and should be considered in the differential diagnosis of phototoxic contact dermatitis.

Phototesting in bath-PUVA: marked reduction of 8-methoxypsoralen (8-MOP) activity within one hour after an 8-MOP bath

It is not known how long after 8-MOP bath-PUVA administration erythema can be induced. Therefore, after determination of dose-dependence and kinetics of bath-PUVA erythema, we investigated the development of erythema using an erythematogenic UVA-dose (3 J/cm2) in time course experiments. Our results show that there is a loss of biological 8-MOP activity already 1 h after 8-MOP bath. This has important consequences for clinical practice with bath-PUVA, concerning the optimum time interval between the 8-MOP bath and irradiation as well as the persistence of photosensitivity in normal skin after bath-PUVA.