bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Some Alkaloids, Flavonoids and Triterpenoids, Contents of Japanese-Chinese Traditional Herbal Medicines, on the Lipogenesis of Sebaceous Glands
Authors: Seki Taisuke , Morohashi Masaaki
Published: April 2009

The effects of some alkaloids and flavonoids, which are major ingredients in some of the Japanese Kampoh drugs (Japanese-Chinese traditional herbal medicines) experientially known to be efficacious for the treatment of acne vulgaris, on the lipogenesis in the sebaceous glands of the hamster ear, an excellent animal model for the human sebaceous gland, were studied. Lipogenesis was assayed by determining 14C incorporation into sebaceous lipids extracted from the sebaceous glands which were preincubated with 14C-acetate. We found that the lipogenesis in the hamster sebaceous glands was suppressed 63 and 54% by 10-4M berberine (an alkaloid) and wogonin (a flavonoid), respectively. We suggest that the therapeutic effects of some Japanese Kampoh drugs experientially used for acne vulgaris could be due to inhibition of lipogenesis by their active ingredients such as berberine and wogonin.
Concentration of Temarotene (Ro 15-0778) and Its Metabolite Ro 14-6113 in Plasma and Skin of Hairless Rat
Authors: Fenina N. , Bun H. , Durand A.
Published: April 2009

The aim of this preliminary report was to measure plasma and skin concentrations of Ro 15–0778 and its phenolic metabolite Ro 14–6113 in hairless rats receiving orally 10 mg/kg of Temarotene once daily during 10 days. Blood (2–3 ml) and skin (200–300 mg) samples were taken at different time points between 0.5 and 240 h after the last dose. We used a highly sensitive HPLC method for simultaneous determination of the two compounds with a quantification limit of 2 ng/ml in plasma and 10 ng/g in total skin (epidermis and dermis). After 10 h, plasma concentrations of Ro 14–6113 were 5–13 times higher than for Ro 15–0778. Ro 14–6113 concentrations in the skin were 4–10 times higher than for Ro 15–0778 within the initial 48 h. The concentrations of both compounds in the skin were higher than concentrations in plasma.
Regulation of Collagen Synthesis in Human Dermal Fibroblasts by the Sodium and Magnesium Salts of Ascorbyl-2-Phosphate
Authors: Geesin Jeffrey C. , Gordon Joel S. , Berg Richard A.
Published: April 2009

Ascorbic acid has been shown to stimulate collagen synthesis in dermal fibroblasts by increasing the rate of transcription of collagen genes. Experiments involving the use of ascorbic acid require daily supplementation due to the instability of the molecule in aqueous solutions. In order to provide a more stable alternative to ascorbic acid, two salts of ascorbyl-2-phos-phate, having a greater chemical stability than ascorbic acid, were tested for their ability to stimulate collagen synthesis in monolayer fibroblast cultures. The concentration and time dependence of their activities were compared with ascorbic acid. The magnesium salt of ascorbyl-2-phosphate was found to be equivalent to ascorbic acid in stimulating collagen synthesis in these assays, while the sodium salt required at least a tenfold greater concentration to produce the same effect as ascorbic acid. Solutions of either ascorbic acid or the ascorbyl-2-phosphate analogs (at 10 mM) in phosphate-buffered saline (PBS) were relatively stable as shown by their decay rates and their ability to stimulate collagen synthesis even after nine days in solution prior to testing their effects on cultured cells. Ascorbic acid was unstable at neutral pH compared to solutions of either sodium or magnesium ascorbyl-2-phosphate. These data support the use of magnesium ascorbyl-2-phos-phate in experiments where stability of ascorbic acid is a concern, e.g. in long-term cultures or in in vivo studies.
In vivo Recovery of Repeatedly Strained Rat Skin after Systemic Treatment with Desmotropic Drugs
Authors: Vogel H.G.
Published: April 2009

The mechanical behavior of rat skin during repeated strain in vivo and the restoration process thereafter were studied following 10 days’ treatment with desmotropic drugs (300 mg/kg p.o. D-penicillamine or 10 mg/kg s.c. prednisolone acetate). Repeated (30 times) elongations of up to 40% were performed under anesthesia both longitudinally and perpendicularly to the body axis. Evaluation of this first run of 30 cycles showed stress values as well as the moduli of elasticity to be decreased after D-penicillamine, whereas they were greatly increased after prednisolone acetate treatment. The decay of stress values during repeated strain revealed similar effects of treatment. In the second part of the experiment, the restoration process was evaluated by a second run of 30 cycles after 1, 6 and 16 h. In the late phases of recovery, an even better restitu-tio ad integrum was found in treated animals. Overall, in contrast to other biomechanical parameters, the restoration process is barely influenced by treatment with desmotropic compounds.
A Large Panel of Microsatellite Markers for Genetic Studies in the Infra-Order Catarrhini
Authors: Roeder Amy D. , Bonhomme Maxime , Heijmans Corrine , Bruford Michael W. , Crouau-Roy Brigitte , Doxiadis Gaby , Otting Nel
Published: April 2009

Many genetic studies on catarrhines use microsatellite markers that were isolated from human DNA. A large number of these markers have been characterized in the great apes, macaques and baboons. However, there are few or no markers available for other members of this group. In this study, an extensive literature search was performed to find microsatellite markers that had been successfully amplified across a range of catarrhine species. These conserved loci can provide a valuable starting point for characterizing loci in other catarrhines. Finally, microsatellite markers were tested in a range of species that are not well represented in the literature.
lnterleukin-8 Production from Cultured Human Dermal Fibroblasts by Stimulation with Supernatant of Cultured Human Epidermal Cells
Authors: Morita Eishin , Yamada Satoru , Kimura Isamu , Nakamura Koji , Sugita Yasushi , Yamamoto Shoso
Published: April 2009

There is much evidence to support the theory that keratino-cytes and dermal fibroblasts actively participate in inflammatory reactions by the production of proinflamrnatory mediators or cytokines. We investigated the neutrophil chemotactic activity in conditioned media of cultured epidermal cells and dermal fibroblasts, and found that an epidermal cell-derived factor induced fibroblasts to produce a neutrophil chemotactic factor. This neutrophil chemotactic factor was identified as interleukin-8 (IL-8) by the elution position on HPLC and by a neutralization test that uses monoclonal anti-IL-8 antibody (14E4). The epidermal cell-derived factor was fractionated together with thymocyte-proliferating activity on Sephadex G-75 gel chromatography followed by HPLC. It was blocked specifically by anti-interleukin-1 (IL-1) Α antibody, which indicates that this factor was IL-1Α. Since a variety of inflammatory dermatoses is characterized by the infiltration of neutro-phils into the skin, induction of IL-8 production in fibroblasts by epidermal cells may play an important role in inflammatory skin diseases.
Comparison of the Bioactivity of Mometasone Furoate 0.1% Fatty Cream, Betamethasone Dipropionate 0.05% Cream and Betamethasone Valerate 0.1% Cream in Humans
Authors: Bjerring Peter
Published: April 2009

The bioactivity of a novel topical glucocorticosteroid, mometasone furoate 0.1 % fatty cream was compared with betamethasone dipropionate 0.05% cream and betametasone valerate 0.1% cream. An ultraviolet light (UV-B)-induced inflammation assay in humans was used, and the combined effect of a single, open application of the corticosteroids was evaluated. Reduction of UV-B induced inflammation was monitored by laser Doppler blood flowmetry, clinical skin scoring and skin reflectance spectrophotometry. Skin scoring and reflectance spectrophotometry were found unsuitable because one of the cream vehicles contained titanium dioxide which shielded skin erythema. Laser Doppler blood flowmetry showed that mometasone furoate 0.1 % fatty cream was more than twofold better in reducing UV-B-induced inflammation than betamethasone dipropionate 0.05% cream and betametasone valerate 0.1 % cream, and that the effect was sustained for at least 24 h after a single application.
Effects of Sphingosine, Isoquinoline and Tannic Acid on the Human Tape-Stripping Model and the Psoriatic Lesion
Authors: Arnold Peter , Glade Conrad P. , Mier Paul D. , van de Kerkhof Peter C.M.
Published: April 2009

Published data (mainly from rodent skin) suggest a correlation between compounds which inhibit protein kinase C (PKC), have anti-inflammatory or antitumor characteristics and possess antipsoriatic potential. We have investigated the effects of topical application of sphingosine (a naturally occurring PKC inhibitor), isoquinoline (a component of coal tar which showed antipsoriatic capacities in the mouse tail model) and tannic acid (a plant phenol with antitumor activity) on human skin. In each case we have assessed (a) the level of induction of ornithine decarboxylase (ODC) following Sellotape® stripping as an indicator for potential PKC inhibition in vivo, and (b) its effects on the lesions of chronic plaque psoriasis. The control group consisted of 18 healthy volunteers, used for the ODC induction experiments (0.0/0.1/0.2 M sphingosine in ethanol, 100% coal tar and 0/50 mM tannic acid in acetone) and 17 psoriatic patients used for double-blind scoring of two randomly selected lesions (0.0/0.1 M sphingosine in ethanol, 0.0/0.2% isoquinoline in white vaseline/lanette wax cream 50%/50% and 0/10% tannic acid in lanette wax cream) and also for some of the ODC induction experiments (0.0/0.2% isoquinoline and 0/10% tannic acid). Biopsies were taken 8 h after stripping and ODC activity was assessed by measurement of 14CO2 release. Lesions were scored with a modified psoriasis area and severity index on days 0,7 (isoquinoline and tannic acid), 13 (sphingosine) and 21 (isoquinoline and tannic acid). Application of 0.1 or 0.2 M sphingosine resulted in a decrease of ODC activity of 52% and 66%, respectively (p < 0.01), but histologic sections showed intraepidermal necrosis. Isoquinoline, coal tar and tannic acid did not have any significant influence on ODC induction (p > 0.05). All compounds failed to show significant improvement of the psoriatic lesions. Therefore we may conclude that ‘theoretical’ antipsoriatic agents may be limited in practice by cytotoxicity and hence a narrow therapeutic index, poor penetration and lack of specificity. Further, a marked difference between the effects of these compounds on the skin of different species increases the difficulty of predicting antipsoriatic activity.
In vivo Evaluation of the Stratum corneum Barrier Function in Blacks, Caucasians and Asians with Two Noninvasive Methods
Authors: Kompaore F. , Marty J.P. , Dupont Ch.
Published: April 2009

This study compared in man the in vivo barrier function of stratum corneum in three racial groups: black, Caucasian and Asian, by two noninvasive technics. They were transepidermal water loss (TEWL) determination measured with an evaporimeter and laser Doppler velocimetry (LDV) to measure the lag time before the vasodilatation induced by application of methyl nicotinate (10 μl of 0.5% solution in ethanol/propylene glycol 95/5 v/v). Both methods were performed simultaneously on each forearm of 7 black, 8 Caucasian and 6 Asian subjects before and after removal of the stratum corneum by stripping. TEWL measurements were higher (p < 0.01) in Asians and Blacks compared to Caucasians. Stripping (8 or 12 strips) increased TEWL in all groups; TEWL increase percentage was higher (p < 0.05) in Asians compared to Caucasians. Vasodilatation lag times assessed by LDV showed that skin permeability was more important in Asians (p < 0.01) and in Caucasians (p < 0.05) than in blacks. Lag times decreased with stripping. After 8 or 12 strips, the order of sensitivity was: Asian > Caucasian > black. Our study showed that, with both noninvasive methods, removal of the stratum corneum increased permeability, with racial differences.
Comparative Study of the Activity and Lingering Effect of Topical Antifungals
Authors: Piérard Gérald E. , Piérard-Franchimont Claudine , Arrese Estrada Jorge
Published: April 2009

We present a combined method of culturing pathogenic der-matophytes and yeasts on human stratum corneum. Topical marketed antifungals are applied in vivo, and the stratum corneum is removed by cyanoacrylate skin surface strippings. After inoculation of the test organism, the extent of fungal growth is measured, indicating by comparison with controls the level of inhibitory effect of the antifungal. Other samples of stratum corneum collected at different time intervals after the arrest of antimicrobial treatment are used to evaluate the lingering effect of the drug. The combination of the data gained by these approaches close to the in vivo situation is used to introduce a classification of antifungals.
Ultrastructural Localization and Quantification of Extracellular Calcium Binding Sites in Mouse Vibrissa and Human Scalp Follicles
Authors: Mills Cynthia J. , Buhl Allen E. , Ulrich Roger G. , Diani Arthur R.
Published: April 2009

The purpose of these experiments was to determine if an extracellular calcium binding site gradient is evident in freshly dissected or cultured mouse vibrissa and human scalp follicles and to measure possible drug effects on this gradient. Mouse vibrissae were cultured with or without either minoxidil or pinacidil, and human scalp follicles were cultured with or without epidermal growth factor. Anagen vibrissa and scalp follicles were dissected and placed in culture for 4 h to 4 days, then fixed in a solution containing lanthanum chloride and prepared for either quantitative energy-dispersive X-ray microanalysis (X-ray) or qualitative transmission electron microscopy (TEM). Since lanthanum has a high charge density it displaces Ca2+ ions from anionic binding sites. TEM analysis revealed extensive accumulation of electron-dense lanthanum deposits in the intercellular compartment of differentiating cells in the hair shaft and inner root sheath in the apex of the follicular bulb. Sparse lanthanum precipitate was observed in the intercellular space of the proliferative cells at the base of the bulb. This gradient of lanthanum precipitate was evident in both freshly dissected and cultured vibrissa and scalp hair follicles, irrespective of treatment with drugs that grow hair or epidermal growth factor. X-ray microanalysis indicated that percent by weight of lanthanum was markedly higher in the apex compared to the base of the follicular bulb in vibrissa and scalp follicles. These qualitative and quantitative data demonstrate that an extracellular calcium binding site gradient exists in cultured vibrissa and scalp hair follicles, and that this gradient is not significantly affected by hair growth altering drugs including minoxidil or pinacidil, and epidermal growth factor.
Evaluation of Phototoxic and Photogenotoxic Risk Associated with the Use of Photosensitizers in Suntan Preparations: Application to Tanning Preparations Containing Bergamot Oil
Authors: Moysan A. , Morlière P. , Averbeck D. , Dubertret L.
Published: April 2009

Bases for the elaboration of a standardized protocol are proposed for studying phototoxic effects of skin tanning preparations containing photosensitizing agents. The experimental procedure includes in vivo phototoxicity tests, evaluation of the photogenotoxic risk and determination of the photosensitizer concentration in plasma after topical application. This procedure was carried out with tanning preparations containing a well-known photosensitizer, 5-methoxypsoralen, as a component of bergamot oil. The whole study has been performed using topical application of the commercial suntan product, i.e. containing the sunscreens and all other components. Whereas the exposure to solar simulated radiation never triggered any phototoxic response, a photosensitizing effect was observed for skin type I volunteers exposed to high doses of ultraviolet A. The transepidermal penetration resulted in a 5-methoxypsoralen concentration of 1-4 ng/ml in the suction blister fluid. The photogenotoxicity of this suction blister fluid containing 5-methoxypsoralen and also other ingredients of the tanning preparation was assayed on yeast cells and was found to be rather low. 5-Methoxypsoralen was also detected in plasma after repeated applications but at low concentrations (about 1 ng/ml) which do not present a potential risk for systemic ocular effects.
Quantitative Evaluation of Drug-Induced Erythema by Using a Tristimulus Colour Analyzer: Experimental Design and Data Analysis
Authors: Chan S.Y. , Po A. Li Wan
Published: April 2009

Pulsed-light reflectance using the Minolta® Chroma Meter CR-200 was evaluated as a quantitative method for the non-invasive assessment of drug-induced erythema on the flexor surface of the forearm. Nicotinate esters were used as model vasodilators. Several parameters derived from the data were analysed using analysis of variance (ANOVA) and Tukey’s multiple range tests appropriate for the study designs used. The effects of varying concentrations of methylnicotinate and of different nicotinate esters were found to be statistically significant. This non-invasive technique was found to be particularly useful in ranking the cutaneous responses elicited by the topical application of increasing concentrations of methylnicotinate in a single subject, as well as in a group of 6 volunteers.
Signal Transduction by Retinoid Receptors
Authors: Pfahl Magnus
Published: April 2009

Vitamin A derivatives (retinoids) affect a large variety of fundamental biological processes. Understanding of the signaling mechanism has been greatly advanced by the cloning of specific retinoid receptors. These regulatory proteins belong to the steroid/thyroid hormone nuclear receptor superfamily. Two types of retinoid receptors have been identified, the retinoic acid receptors (RARΑ, Βand Γ) and the retinoid X receptors (RXRΑ, Β, and Γ). Similar to the steroid hormone receptors, the retinoid receptors bind to specific DNA sequences that have diad symmetries. However, the RARs require hete-rodimerization with RXRs for efficient DNA binding and gene regulation, while the RXRs can bind to DNA and function as homodimers in the presence of 9-cis-retinoic acid. In addition, RXRs can form heterodimers with thyroid hormone receptors and the vitamin D3 receptor and other receptors. Thus the RXRs have a very central role in serving as a partner for several hormone and vitamin receptors and thus may allow cross talk between different hormone signals. Retinoid responses can be restricted by the COUP-TF orphan receptors which bind to overlapping DNA sequences. Besides the classical way of action via DNA binding, the retinoid receptors can also interfere with other signaling pathways by interacting with the transcription factor AP-1. The advances made in understanding the mechanism of action of retinoids promise to contribute to the understanding and control of physiological responses and diseases
Pharmacological Effects of Retinoids on Skin Cells
Authors: Gendimenico Gerard J. , Mezick James A.
Published: April 2009

Retinoids exert profound pleiotropic effects in skin, affecting many aspects of cell differentiation and proliferation. For this reason, retinoids have prominent pharmacological effects on major skin cells (keratinocytes, dermal fibroblasts, melanocytes, sebocytes) and have shown great potential as therapeutic agents in dermatology. In keratinocytes, retinoids induce proliferation, resulting in epidermal hyperplasia. Retinoids also modulate epidermal differentiation, however, many of the suppressive effects of retinoids observed in vitro do not occur in vivo. Dermal fibroblasts are important target cells of retinoids and are stimulated to produce extracellular matrix proteins, particularly when skin is damaged by wounding, ultraviolet radiation or glucocorticoids. Retinoids regulate pigmentation and can lighten hyperpigmented skin in animals and humans. Studies with cultured melanocytic cells show that tyrosinase activity is reduced by retinoids. The powerful sebosuppressive effect of some retinoids, such as 13 cis-retinoic acid, demonstrates that sebocyte differentiation is altered by retinoids. Retinoids inhibit proliferation and lipid synthesis in cultured human sebocytes and alter their keratin expression.
Clinical Aspects of Topical Retinoids
Authors: Biro David E. , Shalita Alan R.
Published: April 2009

Topical retinoids have been employed in dermatology since the 1960s to treat a wide variety of cutaneous disorders. This review focuses on three areas in which retinoids have had their greatest impact: acne vulgaris, photoaging and cutaneous neo-plasia. The pharmacology of the available topical retinoids, their mechanism of action and the history of their use in these disorders are discussed.
Treatment of Photoaged Skin with Topical Tretinoin
Authors: Kligman Albert M. , Leyden James J.
Published: April 2009

Once-daily application of tretinoin to photodamaged facial skin for 0-12 months results in substantial clinical and histologic improvement. As regards appearance, fine wrinkles become effaced, dyspigmentations fade, surface becomes smooth and develops a ‘rosy glow’. Histologically, atrophy and dysplasia of the epidermis are completely corrected. New collagen is laid down subepidermally along with the development of new small vessels (angiogenesis). Mesenchymal dermal cells become more numerous and larger. The sum of changes is toward more youthful skin.
Transient Urinary Ascites after Vesicocentesis Observed in a Fetus with Megacystis Caused by Posterior Urethral Valve
Authors: Hidaka Nobuhiro , Chiba Yoshihide
Published: April 2009

Background: Fetal urinary ascites is a condition that is rarely encountered. A review of previous reports suggests that the clinical course of the affected fetuses is highly variable. Methods: In this report, we describe a case in which urinary ascites was observed after vesicocentesis in a fetus with megacystis caused by posterior urethral valve. Results: The urinary ascites was transient, and the fetal outcome was good after a successful vesicoamniotic shunting operation. Conclusions: In utero bladder rupture or injury and the subsequent appearance of urinary ascites may be well tolerated by the fetus. Further, spontaneous resolution can be expected during fetal life; therefore, it appears to be preferable to opt for conservative management in fetuses with urinary ascites. Urinary ascites, particularly after vesicocentesis, should be observed with extreme caution.
The Role of Epidermal Proliferation in the Pathogenesis of Psoriasis
Authors: van de Kerkhof P.C.M. , van Erp P.E.J.
Published: April 2009

The micromorphological appearance of the psoriatic lesion is characterized by cutaneous inflammation, epidermal acanthosis and abnormal keratinization. The relevance of immunological factors has been reviewed in recent literature. Despite a longstanding interest of many centres in the pathogenesis of psoriasis, the position of epidermal proliferation, a key feature of the psoriatic plaque, remains to be established. The aim of the present review was to provide evidence from the literature and from our own work that enables us to answer the question to what extent epidermal proliferation might be a primary pathogenetic event or whether it represents a secondary phenomenon resulting from other abnormalities.
Improved Method for Studying Skin Lipid Samples from Cyanoacrylate Strips by High-Performance Thin-Layer Chromatography
Authors: Röpke Eva-Maria , Augustin Wolfgang , Gollnick Harald
Published: April 2009

A non-invasive method for sampling skin surface lipids is cyanoacrylate stripping (CAC-TS). It was the purpose of our study to improve the method for sampling of skin surface lipids and the separation of epidermal lipid fractions by a modification of the methods described by Melnik and by Imokawa et al. Briefly, lipids on the glass slide sampled by CAC-TS from the forearm of 75 volunteers and from the forehead of 60 volunteers were eluted in hexane/ethanol under ultrasonication. Identification of the diluted total superficial sebaceous and epidermal skin lipids was performed by sequential high-performance thin-layer chromatography. For quantification of the lipids we used densitometric methods. By this modified method we were able to show a clear and complete separation of all relevant lipids from a cyanoacrylate strip that represented 1-2 mg stratum corneum only.
Antifungal Activity of the Essential Oil of Melaleuca alternifolia (Tea Tree Oil) against Pathogenic Fungi in vitro
Authors: Nenoff P. , Haustein U.-F. , Brandt W.
Published: April 2009

The in vitro antifungal activity of tea oil, the essential oil of Melaleuca alternifolia, has been evaluated against 26 strains of various dermatophyte species, 54 yeasts, among them 32 strains of Candida albicans and other Candida sp. as well as 22 different Malassezia furfur strains. Minimum inhibitory concentrations (MIC) of tea tree oil were measured by agar dilution technique. Tea tree oil was found to be able to inhibit growth of all clinical fungal isolates. For the investigated dermatophytes MIC values from 1,112.5 to 4,450.0 μg/ml with a geometric mean of 1,431.5 μg/ml were demonstrated. Both C. albicans strains and the other strains belonging to the genus Candida and Trichosporon appeared to be slightly less susceptible to tea tree oil in vitro. However, their MIC values, which varied from 2,225.0 to 4,450.0 μg/ml (geometric mean 4,080 μg/ml), indicated moderate susceptibility to the essential oil of M. alternifolia. The lipophilic yeast M. furfur seemed to be most susceptible to tea tree oil. MIC values between 556.2 and 4,450.0 μg/ml (geometric mean 1,261.5 μg/ml) were found against the tested M. furfur strains. However, when calculated as percentage tea tree oil of the agar, the above-mentioned concentrations correspond to 0.5-0.44% tea tree oil content. These values are far below the usual relatively high therapeutic concentrations of the agent; approximately 5-10% solution or even the concentrated essential oil are used for external treatment. In comparison with tea tree oil, in vitro susceptibility against miconazole, an established topical antifungal, was tested. As expected, very low MIC values for miconazole were found for dermatophytes (geometric mean 0.2 μg/ml), yeasts (geometric mean 1.0 μg/ml), and M. furfur (geometric mean 2.34 μg/ml). It is suggested that the in vivo effect of tea tree oil ointment in the therapy of fungal infections of the skin and mucous membranes as well as in the treatment of dandruff, a mild form of seborrheic dermatitis, may be at least partly due to an antifungal activity of tea tree oil.
Pharmacodynamic Measurements of 8-Methoxypsoralen in Human Skin
Authors: Liu Ping , Ademola John , Amin Smita , Maibach Howard I.
Published: April 2009

The efficiency of the epicutaneous microcirculation is important to the elicitation of pharmacological effects and percutaneous absorption of drugs. Laser Doppler flowmeter, chroma-meter and measurement of transepidermal water loss (TEWL) were used to assess the extent of skin blood flow, water loss and light absorption induced after topical administration of 8-methoxypsoralen (8-MOP). TEWL monitors barrier function directly, while the chromameter measures the light reflected by the skin. Irrespective of the concentration of 8-MOP applied, there is a good correlation between chromameter and evaporimeter readings. However, different drug concentrations elicited significant differences between laser Doppler flowmetry (LDF) and TEWL readings. The response measured with LDF was faster and greater when compared with the other measurements, suggesting that 8-MOP caused a rapid and intense response in skin blood flow. Superficial responses, such as those produced by light reflectance (chromameter) and transepidermal perturbations, were weaker following topical application of 8-MOP combined with UV irradiation (PUVA). This information may be important in delineating guidelines for the clinical practice and instrumental monitoring of topical 8-MOP. These observations suggest that LDF provides a useful, noninvasive physical technique to monitor skin after PUVA. However, caution should be exercised in the interpretation of physical measurements for evaluating the degree of the clinical vasoresponse produced by PUVA treatment.
Pharmacokinetics of Topically Applied Metronidazole in Two Different Formulations
Authors: Dykes Peter , Hill Stephanie , Marks Ronald
Published: April 2009

Topical metronidazole is effective in the treatment of papulo-pustular rosacea, a common inflammatory disease of the face. In this study, a comparison of the bio-availability of two topical formulations (A and B) of 0.75% metronidazole has been made. Twenty-four subjects took part in a double-blind study where each was randomly allocated to four groups corresponding to 0.5, 1, 2 and 4 h of treatment. A single application was made to each forearm and after increasing times of contact, samples of stratum corneum were removed by the skin surface biopsy (SSB) technique. After SBB removal, a full-thickness skin biopsy was taken. The tissues were extracted and analysed by an HPLC method. Both formulations showed rapid percutaneous penetration. Formulation A gave the highest concentrations at the lowest levels of the stratum corneum at 4 h. Thus in SSB5, the mean drug concentrations at 4 h were as follows: A, 6.20 ± 1.16 μg cm-2; B, 1.93 ± 0.98 μg cm-2. A similar difference was observed when the levels in the punch biopsies were determined. At 4 h, the mean drug levels were: A, 6.07 ± 2.17 μgmg-1; B, 0.95 ± 1.16 μgmg-1. Formulation A clearly gives a higher rate of percutaneous penetration leading to higher tissue levels of drug. Whether this increase leads to a clinically more effective treatment has yet to be determined.
Assessment of the Activity of Tacalcitol on Psoriatic Plaques by Means of Colorimetry and High-Frequency Ultrasound: A Double-Blind Intrasubject Half-Side Right-Left Comparison with Betamethasone Valerate and Placebo
Authors: Seidenari Stefania , Magni Rita , Giannetti Alberto
Published: April 2009

The aim of our study was to further investigate and to objectively assess the effects of tacalcitol on psoriasis by means of double-blind comparisons with placebo and betamethasone valerate, documented by instrumental evaluation. The study was conducted as intrasubject half-side right-left comparisons. Twelve subjects entered a double-blind placebo-controlled treatment (tacalcitol/placebo group), whereas 14 subjects received double-blind medication with tacalcitol/betamethasone valerate. Medications were applied once daily without occlusion to affected skin areas. Instrumental evaluations were carried out by means of a colorimeter and a 20-MHz B scanner. The colour co-ordinate a*, representing the colour range from green (-) to red (+), was used for assessing erythema. B scan images were processed according to segmentation procedures. A 0-10 interval, marking the hyporeflecting dermal areas, was used for assessing oedema and inflammatory infiltration at psoriatic plaque sites. Twenty-two patients (11 of the tacalcitol/betamethasone group and 11 of the tacalcitol/ placebo group) completed the treatment period. Mean a* values showed an increase in the tacalcitol/betamethasone group after the first week of therapy on both sides, followed by a slight decrease, the values of which did not reach statistical relevance for either treatment. The decrease observed at tacalcitol-treated sites in patients of the tacalcitol/placebo group was not significant either with respect to baseline values during the first weeks of therapy. The extension of 0-10 dermal areas decreased both in betamethasone- and tacalcitol-treated areas in both patient groups. No significant differences were noticeable between the two treatments at all assessment points, although both by clinical and echographic evaluation a more pronounced decrease in clinical scores and in echogenicity values was observable at betamethasone-valerate-treated sites, especially at weeks 6 and 8. According to our data, assessment of erythema does not always represent a valid method for monitoring the response to therapy in psoriatic patients. In fact, modifications of a* values did not allow a distinction between different treatments, whereas processing of echographic images by the 0-10 segmentation enabled tacalcitol to be classified as a topical drug, the activity of which approaches that of a potent steroid.
A Skin Equivalent Model for Cosmetological Trials: An in vitro Efficacy Study of a New Biopeptide
Authors: Augustin Corinne , Frei Valérie , Perrier Eric , Huc Alain , Damour Odile
Published: April 2009

The European Community directive, imposing that effects claimed for cosmetic actives must be validated using non-animal procedures, has stimulated the use of in vitro models for pharmacotoxicological trials. In this paper, an efficacy study of a new biopeptide, a hydrolysate obtained by fermentation of milk proteins, was performed using an in vitro skin equivalent (SE). This SE is obtained by seeding normal human kera-tinocytes onto a dermal equivalent comprising a collagen-gly-cosaminoglycan(GAG)-chitosan porous matrix populated by normal human fibroblasts, which neosynthesize their own extracellular matrix (ECM). A gel containing 2% milk biopeptide was applied topically (10 μl) every 2 days during 15 days. Subsequent investigations of the biopeptide effects were based on morphological criteria after histological analysis and on synthesis of ECM components. Collagen and GAG synthesis were measured by tritiated proline, glucosamine and Na235SO4 incorporation. Qualitatively, the histological features of the biopeptide-treated SEs showed a thicker epidermis than the untreated control SEs, where only a few layers of stratum corneum were observed. The dermal porous matrix seems to be more filled by neosynthesized ECM than the control. Quantitatively, milk biopeptide treatment induced a significant activation of hyaluronic acid (+46%) and sulfated GAG (+53%) synthesis, whereas only non-significant increases of total protein and collagen synthesis were observed (Student’s test, p < 0.001).
Bisindolylmaleimide Protein-Kinase-C Inhibitors Delay the Decline in DNA Synthesis in Mouse Hair Follicle Organ Cultures
Authors: Harmon Charles S. , Nevins Thomas D. , Ducote Janet , Lutz Diane
Published: April 2009

We have used a series of bisindolylmaleimide selective pro-tein-kinase C (PKC) inhibitors to investigate the role of this enzyme in the regulation of cell proliferation in mouse hair follicle organ cultures. Mouse whisker follicles were isolated by microdissection, and rates of DNA synthesis during culture were determined from 3H-thymidine incorporation. The bis-indolylmaleimides Ro 31-7549, Ro 31-8161, Ro 31-8425 and Ro 31-8830 inhibit isolated brain PKC with IC50 values of 8-80 nM, are > 60-fold less potent against protein kinase A, and inhibit PKC-mediated protein phosphorylation in platelets with IC50 values in the range 0.25-4.4 μM. These PKC inhibitors were found to increase levels of mouse hair follicle DNA synthesis, with EC50 values in the range 1-4 μM and maximal levels in the range 151-197% of control. Ro 31-7549 had an IC50 value 50-fold lower than that of minoxidil, while the maximal level of DNA synthesis for the PKC inhibitor was 86% higher. Incubation of mouse hair follicles with Ro 31-7549 resulted in a delay of approximately 24 h in the onset of decline in follicular DNA synthesis rates. Ro 31-6045 and Ro 31-7208, bisindolylmaleimides without activity in the platelet PKC assay, did not affect mouse hair follicle DNA synthesis rates. Taken together, these findings show that PKC mediates, at least in part, the rapid loss of proliferative activity that occurs in mouse whisker follicles in culture, and provide further evidence that PKC plays a role as a negative proliferative signal in hair follicles.
The Effect of Tamol on Human Mast Cell Chymase and Plasmin
Authors: Wiedow Oliver , Weindler Friedrich , Mrowietz Ulrich
Published: April 2009

Tamol is widely used in the therapy of inflammatory derma-toses. It has pronounced astringent properties and is able to inactivate the neutrophil-derived elastase. Since plasminogen activation and release of mast cell chymase may occur in acute dermatitis, we investigated the inhibitory properties of tamol for these enzymes. Tamol proved to be a potent inhibitor of plasmin and mast cell chymase in concentrations relevant for use in dermatotherapy. The inhibition of mast cell chymase and plasmin by tamol was linear and non-competitive. The inactivation of proteolytic enzymes with the capacity to degrade extracellular-matrix proteins may be one of the major clinical effects of tamol in the treatment of acute inflammatory dermatoses.
Sebaceous-Gland Deposition of Isotretinoin after Topical Application: An in vitro Study Using Human Facial Skin
Authors: Tschan T. , Steffen H. , Supersaxo A.
Published: April 2009

As yet, topically applied isotretinoin fails to show convincing clinical efficacy in the treatment of severe recalcitrant acne. Although the reason for this is not known, it is possible that topical application results in low, pharmacologically inactive isotretinoin concentrations in the sebaceous glands, the most likely site of isotretinoin action. It has been suggested that topically applied liposomes enhance the delivery of drugs into the sebaceous glands. Accordingly, we compared the isotretinoin concentration in sebaceous glands and other skin compartments following topical application of small unilamellar vesicles, multilamellar vesicles, preformed vesicles (Natipide® II) or mixed micelles of lecithin and bile salt. We found that the concentration of isotretinoin measured in the sebaceous glands varied between 0.17 and 1.57 ng/mg tissue. The comparison between ethanolic gel and liposomal or micellar gel did not reveal any significant difference. However, application of the Natipide formulation resulted in significantly lower isotretinoin concentrations in the sebaceous glands when compared to the ethanolic gel. Autoradiography and fluorescence microscopy indicated that isotretinoin penetrated the sebaceous glands along the follicular route. In conclusion, our in vitro study showed that, following topical administration, substantial amounts of isotretinoin were delivered to the sebaceous glands via the follicular route, whereby the ethanolic gel was as efficient as a liposomal or a mixed micellar gel.
Effects of Ethyl α-D-Glucoside on Skin Barrier Disruption
Authors: Kitamura Nobuo , Ota Yukiko , Haratake Akinori , Ikemoto Takeshi , Tanno Osamu , Horikoshi Toshio
Published: April 2009

Daily treatments of skin in hairless mice with concentrates of rice wine, Japanese traditional alcohol, lowered transepidermal water loss levels compared to the controls on the 3rd day after ultraviolet B (UVB) irradiation. These findings indicate that the concentrates of rice wine suppress the murine skin barrier disruption caused by UVB. Ethyl Α-D-glucoside (Α-ethylglucoside), one of the peculiar components in rice wine, showed the same effect, whereas Β-ethylglucoside had no effect. In order to clarify the functions of Α-ethylglucoside on murine skin, we examined the effects of this compound on the expression of some phenotypes in human keratinocytes in vitro. As a result, Α-ethylglucoside as well as Β-ethylglucoside enhanced cell proliferation weakly, and the formation of cornified envelopes and differentiated type keratin (K1) in keratinocytes was accelerated by Α-ethylglucoside but not by Β-ethyl-glucoside. From the results, we concluded that Α-ethylglucoside enhanced the differentiation of keratinocytes, which might be related to reduced barrier disruption by UVB.
Effect of Percutaneous Absorption of Fluocinolone Acetonide on the Activity of Superoxide Dismutase and Total Antioxidant Status in Patients with Psoriasis
Authors: Gavan Norina , Popa Ruxandra , Orasan Remus , Maibach Howard
Published: April 2009

This study defines a modification of antioxidant systems by percutaneous absorption of fluocinolone acetonide. Total antioxidant status (TAS) provides an overall indication of antioxidant status. Superoxide dismutase (SOD), a primary antioxidant, accelerates the dismutation of the toxic superoxide radical produced during the oxidative energy processes into the less harmful molecules, hydrogen peroxide and molecular oxygen. We monitored the level of SOD and TAS in 7 males with psoriasis and 6 control subjects before and after a single application of fluocinolone acetonide 0.025% ointment to 90% of the body. The results showed that the plasma level of TAS was significantly increased (p < 0.02) at 24 h posttreat-ment. The erythrocytic level of SOD was significantly decreased (p < 0.01) only at 12 h after glucocorticosteroid application. The level of TAS and SOD in patients with psoriasis was also significantly increased (p < 0.01 for both situations) as compared to healthy controls. Our study suggests that fluocinolone acetonide as a therapeutic agent may play a role in the oxidative stress in skin diseases.
Experimentally Induced Pruritus and Cutaneous Reactions with Topical Antihistamine and Local Analgesics in Atopic Eczema
Authors: Weisshaar Elke , Forster Clemens , Dotzer Markus , Heyer Gisela
Published: April 2009

We investigated the antipruritic effect of a 15-min application of dimethindene maleate (Fenistil® gel) and other local analgesics (Optiderm®, EMLA®, Xylocain® ointment 5%) on subsequent focal histamine stimulus (20 mC) given by iontophoresis in 12 patients suffering from acute atopic eczema (AE). The results were compared to histamine after pretreatment with the respective placebo and to non-pretreated skin. Wheal and flare areas were planimetrically evaluated. Itch or pain ratings were performed over a 24-min period using a rating scale. The examination also comprised alloknesis, i.e. induction of a peri-focal itch sensation by a non-itching mechanical stimulus. None of the antihistaminic and anaesthetic agents reduced the itch intensity significantly. Three of the AE patients had a total lack of alloknesis. We conclude that these substances, when applied for 15 min, are not sufficiently effective in atopic skin suppressing histamine-induced reactions under experimental conditions. The diminished elicitation of alloknesis in these patients may be a result of central nervous system alteration.
Inhibition of Skin Protein Kinase C by Psychotropic Drugs
Authors: Vaitla Rama , Roshani Pashootan , Holian Oksana , Cook Brian , Kumar Raj
Published: April 2009

Lipid-soluble psychotropics are often used to treat skin diseases with psychosomatic indications. Although these drugs are known to exert their effects through the central nervous system, relatively little is known about their mechanism of action in skin. In this communication, several lipid-soluble psychotropic drugs have been examined for their ability to inhibit protein kinase C (PKC)-catalyzed phosphorylation of exogenous substrates and endogenous skin proteins. Phosphorylation of three discrete skin protein substrates at 64, 42 and 28 kDa and a group crowded together at 15-18 kDa was prevented by the antidepressants/antipsychotics. Inhibition was more pronounced in a phospholipid (PL) dependent system, but both drug-PL and drug-PKC interactions seem to be important in the mechanism of action of these drugs. In addition to the tricyclic nucleus, the propanamine side chain or its N-methyl form may influence the interaction of these drugs with PKC and its substrate(s). Chlorpromazine, imipramine, fluoxetine, doxepin, amitriptyline and hydroxyzine used in the practice of dermatology may exert their therapeutic effects by modulating skin PKC activity.
Biphasic Effects of Minoxidil on the Proliferation and Differentiation of Normal Human Keratinocytes
Authors: Boyera N. , Galey I. , Bernard B.A.
Published: April 2009

Minoxidil is the most used drug with proved effects in the treatment of androgenetic alopecia (AGA), but little is known about its pharmacological activity and target cells in hair follicles. As AGA is characterized by follicle atrophy, accelerated hair cycles and hair fiber thinning, we postulated that kerati-nocyte proliferation/differentiation is affected and we tested Minoxidil’s effects on those parameters. Normal human keratinocytes (NHK) of follicular or epidermal origin were cultured in the presence of Minoxidil (0, 0.1, 1, 10, 100, 1,000 μM) during 5-8 days in various media (high-/low-calcium content, with or without serum). Proliferation was assessed by mitochondrial dehydrogenase activity (XTT), BrdU incorporation, lysosome numeration (neutral red incorporation) and total protein dosage. Drug-induced cytotoxicity was measured by lactate dehydrogenase release in culture supernatant, and pro-differentiating effects were evaluated by relative involucrin expression (ELISA dosage). On this basis, we showed that Minoxidil had biphasic effects on the proliferation and differentiation of NHK: Minoxidil stimulated NHK proliferation at micromolar doses, while antiproliferative, pro-differentiative and partially cyto-toxic effects were observed with millimolar concentrations. We can hypothesize that Minoxidil hypertrichotic activity in vivo is possibly mediated by the maintenance of proliferative potential in follicular keratinocytes precociously committed to differentiation.
Influence of Indoles (Melatonin, Serotonin and Tryptophan) on the Porphyrin Metabolism in vitro
Authors: Kalka K. , Fritsch C. , Bolsen K. , Verwohlt B. , Goerz G.
Published: April 2009

We examined the influence of melatonin, serotonin and tryptophan on the basal and δ-aminolevulinic acid (ALA)-induced porphyrin content in HaCaT, SKMel-23 and HepG2 cells. ALA-preincubated and ALA-free cells were fed with medium containing 1 mM melatonin, serotonin or tryptophan. After 24 h the porphyrin content in the cells and in the culture medium was measured. In the three cell lines the inbucation with 1 mM ALA over 24 h increased the porphyrin concentration in all cell lines in different degrees: HepG2 > SKMel-23 > HaCaT cells. In HepG2 cells, neither melatonin, serotonin nor tryptophan influenced ALA-induced porphyrin concentrations significantly, but all three indoles depressed the porphyrin levels in SKMel-23 and HaCaT cells. The indoles may decrease the ALA uptake in HaCaT or SKMel-23 cells. Another mechanism could be the inhibition of enzymes converting ALA into porphyrins.
Effect of Bile Acids on the Growth and Differentiation of Cultured Human Keratinocytes
Authors: Vessey Donald A. , Lee Kyung-Hee , Lau Eva
Published: April 2009

Sixteen bile acids were tested at a concentration of 50 µM for their effect on growth of preconfluent cultures of proliferating keratinocytes. Monohydroxy bile acids (3-Β-hydroxy-Δ5-cho-lenate and lithocholate) stopped the accumulation of protein, dramatically decreased DNA content and led to a 90% loss of cell viability. Deoxycholate (DOC) and chenodeoxycholate inhibited protein accumulation and blocked increases in DNA content, without affecting cell viability. DOC had measurable growth-retarding effects at concentrations as low as 15 µM, and lithocholate at 2 µM. The glycine and taurine conjugates of bile acids were significantly less effective inhibitors of growth, as was the sulfate conjugate of lithocholic acid. DOC and chenodeoxycholate at 25-50 µM enhanced the differentiation-specific increase in particulate transglutaminase activity by as much as 80% over 6 days. Lithocholate had a similar effect at 5 µM. Glycine and taurine conjugates of DOC had a similar effect but were less potent; tauroursodeoxycholate had no effect. The data indicate that bile acids, at levels seen in obstructive biliary disease, can lead to a down-regulation of keratinocyte growth and an up-regulation of differentiation.