[Effect of hormonal replacement therapy on cutaneous biophysical properties of menopausal women]

PURPOSE

The aim of this analysis was to study the possible effect of hormonal replacement therapy on some biophysical properties of the skin of menopausal women.

SUBJECTS AND METHODS

A study was carried out on 106 menopausal, phototype I to IV women with clinically healthy skin. During the medical evaluation, the menopausal status, duration of the menopause, and, possible use of hormone replacement therapy and its duration were collected. A series of biophysical skin parameters in controlled environmental conditions was assessed on the face: sebum casual level, skin surface pH, skin colour, transepidermal water loss, capacitance, conductance, skin relief and temperature. The same parameters except for sebum were assessed on the forearm. Three sub-samples were defined according to the duration of the menopause and of hormone replacement therapy.

RESULTS

The skin colour parameters revealed a greater red intensity value in menopausal women who had been treated for at least one year. In menopausal women who had been treated for at least 5 or 10 years, the biophysical measurements were significantly higher for the parameters evaluating hydration and sebum secretion, associated with higher values for the yellow intensity parameter and the skin relief parameters on the forehead.

CONCLUSION

These results support the subjective impression and the clinical evaluation according to which hormonal replacement therapy could modify the development and the severity of some properties associated with skin ageing after the onset of menopause.

Believe it or not--silver still poisons!

For centuries, silver has been endowed with therapeutic benefits. It is still used today as a "caustic" for superficial bleeding. Within 7days, we had 3 cases of "argyria" and then 2 more over the next month. The first 2 cases involved a husband and wife with a 3-y exposure to naturopathic hydrolyzed silver treatment. The third casewas a 37-y-old male in a state psychiatric facility noted to have darkly "discolored" skin probable obtained from herbal tea. The last 2 cases were a married couple into herbal medications who developed bluish discoloration of face and hands. Current cases due to "alternative medicine" may get worse as rumor reveals its popularity as prophylaxis against anthrax. The skin's grayish discoloration, made worse by sunlight, may persist for life.

Mechanism by which an elevation of extracellular glucide concentration induces pigment aggregation in medaka melanophores

An increase in glucide concentration induces pigment aggregation in melanophores in the skin on scales isolated from the medaka, Oryzias latipes. In this study, hexoses (including the common D-isomers of glucose, galactose, fructose, and mannitol) were examined. Denervated melanophores were refractory to such stimuli. An alpha-adrenolytic agent, phentolamine, effectively blocked the responses of normally innervated melanophores. The pigment-aggregating action of glucide was inhibited by withdrawal of Ca(2+) and Mg(2+) ions from the medium. A specific blocker of voltage-dependent N-type Ca(2+) channels, the omega-conotoxin GVIA, also inhibited the glucide action. The conclusion derived is that an elevation of glucide levels acts to open Ca(2+) channels of presynaptic membranes of sympathetic postganglionic fibers, and the consequently released adrenergic transmitter acts on the effector cells to induce the aggregation of their pigmentary organelles.

The role of nuclear factor-kappa B and melanogenesis in tumor necrosis factor-alpha-induced apoptosis of normal human melanocytes

The proapoptotic potential of tumor necrosis factor-alpha (TNF-alpha) has been demonstrated for various cell types, whereas nuclear factor-kappaB (NF-kappaB) is known to support the transcription of prosurvival genes. In the present study, investigation of normal human melanocytes revealed induction of apoptosis after TNF-alpha treatment (100 U/ml) in only 3 out of 11 cultures analyzed, whereas 8 cultures remained largely resistant. In sensitive cultures, NF-kappaB binding activity was found increased after TNF-alpha treatment; apoptosis-resistant cells were characterized by relatively high basic NF-kappaB binding activities and did not show NF-kappaB activation after TNF-alpha treatment. Inhibition of NF-kappaB by a specific inhibitor, Bay-11, either induced apoptosis itself or resistant melanocyte cultures became sensitive to TNF-alpha treatment. No correlation was found between apoptosis sensitivity and the expression of TNF receptor-1 or the expression of Bax, Bcl-2 and Bcl-X(L). A strong correlation, however, was found regarding the pigmentation degree, as high pigmentation correlated with apoptosis resistance and sensitive melanocyte cultures were weakly pigmented. These data may indicate that in cultured melanocytes, high levels of melanogenesis lead to an increase in oxidative stress which itself causes NF-kappaB activation. NF-kappaB mediates the transcription of antiapoptotic factors which may block TNF-alpha-induced apoptosis at early steps of the signal cascade.

Treatment of melasma with Pycnogenol

Melasma (or chloasma) is a common disorder of cutaneous hyperpigmentation predominantly affecting sun-exposed areas in women. The pathogenesis of melasma is not fully understood and treatments are frequently disappointing and often associated with side effects. Pycnogenol is a standardized extract of the bark of the French maritime pine (Pinus pinaster), a well-known, potent antioxidant. Studies in vitro show that Pycnogenol is several times more powerful than vitamin E and vitamin C. In addition, it recycles vitamin C, regenerates vitamin E and increases the endogenous antioxidant enzyme system. Pycnogenol protects against ultraviolet (UV) radiation. Therefore its efficacy in the treatment of melasma was investigated. Thirty women with melasma completed a 30-day clinical trial in which they took one 25 mg tablet of Pycnogenol with meals three times daily, i.e. 75 mg Pycnogenol per day. These patients were evaluated clinically by parameters such as the melasma area index, pigmentary intensity index and by routine blood and urine tests. After a 30-day treatment, the average melasma area of the patients decreased by 25.86 +/- 20.39 mm(2) (p < 0.001) and the average pigmentary intensity decreased by 0.47 +/- 0.51 unit (p < 0.001). The general effective rate was 80%. No side effect was observed. The results of the blood and urine test parameters at baseline and at day 30 were within the normal range. Moreover, several other associated symptoms such as fatigue, constipation, pains in the body and anxiety were also improved. To conclude, Pycnogenol was shown to be therapeutically effective and safe in patients suffering from melasma.

The effect of niacinamide on reducing cutaneous pigmentation and suppression of melanosome transfer

BACKGROUND

Cutaneous hyperpigmentation occurs in multiple conditions. In addition, many Asian women desire a lighter skin colour. Thus, there is a need for the development of skin lightening agents. Niacinamide is a possible candidate.

OBJECTIVES

To investigate the effects of niacinamide on melanogenesis in vitro and on facial hyperpigmentation and skin colour in vivo in Japanese women.

METHODS

Melanin production was measured in a purified mushroom tyrosinase assay, cultured melanocytes, a keratinocyte/melanocyte coculture model, and a pigmented reconstructed epidermis (PREP) model. The clinical trials included 18 subjects with hyperpigmentation who used 5% niacinamide moisturizer and vehicle moisturizer in a paired design, and 120 subjects with facial tanning who were assigned to two of three treatments: vehicle, sunscreen and 2% niacinamide + sunscreen. Changes in facial hyperpigmentation and skin colour were objectively quantified by computer analysis and visual grading of high-resolution digital images of the face.

RESULTS

Niacinamide had no effect on the catalytic activity of mushroom tyrosinase or on melanogenesis in cultured melanocytes. However, niacinamide gave 35-68% inhibition of melanosome transfer in the coculture model and reduced cutaneous pigmentation in the PREP model. In the clinical studies, niacinamide significantly decreased hyperpigmentation and increased skin lightness compared with vehicle alone after 4 weeks of use.

CONCLUSIONS

The data suggest niacinamide is an effective skin lightening compound that works by inhibiting melanosome transfer from melanocytes to keratinocytes.

A new approach to the evaluation of whitening effect of a cosmetic using computer analysis of video-captured image

Whitening effects of cosmetics have been evaluated with change of skin reflectance of the colorimeter. However, skin color implies Hue (H) and Saturation (S) as well as skin reflectance (Value). We have developed a new evaluation method of change of skin color using computer analysis of the video-captured digital image. We have also investigated whitening effects of a new whitening cosmetic essence, 'Concentre anti-tache nuit' (CAN; Parfums Christian Dior, France), which contained 3% magnesium l-ascorbyl 2-phosphate, on skin color of the face in 15 healthy Japanese females. Measurement was performed after 6 weeks application. Whitening effects were also evaluated with the combination of observation and photographs. CAN showed significant improvement in Saturation of the forehead and left cheek and Value of the forehead. CAN showed greater whitening effects both on the forehead and left cheek in eight (53%) of 15 subjects with the combination of observation and photographs. These results indicated that CAN may have a whitening effect on skin of the face after 6 weeks application. This method may be useful to evaluate the whitening effect of cosmetics and color change of cutaneous disorders.

(4-Methoxy-benzylidene)-(3-methoxy-phenyl)-amine, a nitrogen analog of stilbene as a potent inhibitor of melanin production

The current study was carried out to investigate in vitro the effects of (4-methoxy-benzylidene)-(3-methoxyphenyl)-amine on melanin biosynthesis which is closely related to hyper-pigmentation. (4-Methoxy-benzylidene)-(3-methoxy-phenyl)-amine, a nitrogen analog of stilbene, was synthesized by a single step process. This compound inhibited the tyrosinase activity, which converts dopa to dopachrome in the biosynthetic process of melanin, and showed a UV-blocking effect at UV-B band. The compound also exhibited SOD-like activity, which is involved in the protection against auto-oxidation and inhibited melanin production in melan-a cell line. Our results suggest the possibility that (4-methoxy-benzylidene)-(3-methoxy-phenyl)-amine might be used as a skin whitening agent.

Histamine is involved in ultraviolet B-induced pigmentation of guinea pig skin

We previously reported that histamine induced melanogenesis in cultured human melanocytes and that the stimulatory effect was mediated by protein kinase A activation via H2 receptors. It is well-known that ultraviolet B irradiation causes acute inflammation, known as erythema, and subsequent pigmentation, and there are several reports demonstrating an elevation of the histamine levels in ultraviolet B-irradiated skin. Thus, to evaluate the involvement of histamine in ultraviolet B-induced skin pigmentation, we examined the effect of an H2 antagonist in brownish guinea pig skin. Daily exposure to 200 mJ per cm2 ultraviolet B for 3 d evoked erythema and subsequent pigmentation in the skin samples tested. Moreover, a remarkable increase in dopa-positive melanocytes was observed in the pigmented area, which showed an increase in melanin synthesis. Topical application of famotidine, an H2 antagonist, significantly reduced pigmentation and moderated the increase of dopa-positive melanocytes in the ultraviolet B-irradiated skin. Even when the initiation of famotidine application was delayed to day 2 after irradiation, an inhibitory activity on ultraviolet B-induced pigmentation was observed; however, the ultraviolet B-induced erythema was not suppressed by topically applied famotidine. Thus, we concluded that histamine is involved in ultraviolet B-induced pigmentation and that famotidine suppressed the pigmentation by the prevention of histamine binding to H2 receptors in melanocytes but not by prevention of ultraviolet B permeability and inflammation.

Donor specific response of estrogen and progesterone on cultured human melanocytes

The mechanisms of estrogen and progesterone in human cutaneous pigmentation are largely unknown. The molecular identification of estrogen receptor (ER) and progesterone receptor (PR) in the human melanocytes is of great importance to understand the mechanisms. We performed immunocytochemistry analysis and demonstrated that ER and PR were expressed in the cytoplasms and nuclei of human melanocytes. Reverse transcriptase-polymerase chain reaction (RT-PCR) and sequence analysis confirmed the expression of ER and PR at the transcriptional level. Despite of the presence of ER and PR, the physiological and pregnant levels of estrogen and progesterone showed inconsistent effects on the proliferation and tyrosinase activity of cultured human melanocytes. These results suggest that human melanocytes express ER and PR, which have a donor-specific action in human pigmentation. Further studies are needed to elucidate the induction mechanism and functions of these receptors, and the role of estrogen and progesterone in melanocytes.

Effects of topical and oral vitamin E on pigmentation and skin cancer induced by ultraviolet irradiation in Skh:2 hairless mice

This study investigates whether supplementation with topical RRR-alpha-tocopherol (Eol), topical RRR-alpha-tocopheryl succinate, and oral RRR-alpha-tocopheryl acetate can reduce the incidence of acute and chronic damage to the skin (i.e., sunburn and pigmentation and skin cancer, respectively) induced by ultraviolet (UV) irradiation to mice. Groups of twenty Skh:2 female hairless pigmented mice were treated with 1) lotion vehicle, 2) 5% Eol lotion, 3) 5% topical RRR-alpha-tocopheryl succinate lotion, or 4) lotion vehicle and oral RRR-alpha-tocopheryl acetate. Within each group, 15 mice were exposed to 0.24 J/cm2 of UV-B radiation three times per week. The animals' weights and food intakes were monitored, and the vitamin E concentrations of skin, liver, and adipose tissue were measured to determine whether the topical Eol resulted in significant tissue levels. Skin pigmentation was scored, and the total number of clinically detectable skin tumors per animal was counted weekly. Results showed that the skin concentrations of Eol, as well as levels in the adipose tissue, were increased after topical application. Mice treated with each form of vitamin E showed no signs of toxicity and had significantly less acute and chronic skin damage induced by UV irradiation, as indicated by reduced inflammation and pigmentation and by later onset and lesser incidence of skin cancer.

An epidemiological survey of the use of cosmetic skin lightening cosmetics among traders in Lagos, Nigeria

The use of skin lightening creams has become a socially acceptable phenomenon widely practised by both men and women in Lagos, Nigeria. Four hundred and fifty traders were selected to ascertain the extent of this practice and what socio-cultural and economic factors determine the use of these cosmetics. Prevalence of use of skin lightening cosmetics was 77.3% comprising ninety-six males (27.6%) and two hundred and fifty two females (72.4%). The trend cuts across all socioeconomic strata, age, sex and marital status. Hydroquinolone based products were the most commonly used products although cortico-steroids and mercury-based products were also widely used. Of eleven dermatological side effects that were reported, exogenous ochronosis was the commonest. Recommendations on how to correct this ill in the society have been proffered.

The skin-lightening effects of artocarpin on UVB-induced pigmentation

This study was conducted to evaluate the effects of the prenylated flavonol artocarpin from the heartwood of Artocarpus incisus on ultraviolet (UV)-induced hyperpigmentation of guinea pig skin. An efficient lightening effect was observed following topical application of artocarpin to UV-stimulated hyperpigmented dorsal skins of brownish guinea pigs.

Novel vitamin E derivative with 4-substituted resorcinol moiety has both antioxidant and tyrosinase inhibitory properties

A novel vitamin E derivative, (6"-hydroxy-2",5",7",8"-tetramethylchroman-2"-yl)methyl 3-(2',4'-dihydroxyphenyl)propionate (TM4R), which has a chromanoxyl ring and 4-substituted resorcinol moieties, was synthesized; and its inhibitory effects on tyrosinase, antioxidant ability, and lightening effect of ultraviolet B (UVB)-induced hyperpigmentation were estimated. TM4R showed potent inhibitory activity on tyrosinase, which is the rate-limiting enzyme in melanogenesis. The scavenging activities of TM4R on 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals were found to be nearly the same as those of alpha-tocopherol. Furthermore, an efficient lightening effect was observed following topical application of TM4R to UVB-stimulated hyperpigmented dorsal skin of brownish guinea pigs. These results suggest that TM4R may be a candidate for an efficient whitening agent, possibly by inhibiting tyrosinase activity and biological reactions caused by reactive oxygen species.

Skin pigmentation enhancers

The highest incidences of cancer are found in the skin, but endogenous pigmentation is associated with markedly reduced risk. Agents that enhance skin pigmentation have the potential to reduce both photodamage and skin cancer incidence. The purpose of this review is to evaluate agents that have the potential to increase skin pigmentation. These include topically applied substances that simulate natural pigmentation: dihydroxyacetone and melanins; and substances that stimulate the natural pigmentation process: psoralens with UVA (PUVA), dimethylsulfoxide (DMSO), L-tyrosine, L-Dopa, lysosomotropic agents, diacylglycerols, thymidine dinucleotides, DNA fragments, melanocyte stimulating hormone (MSH) analogs, 3-isobutyl-1-methylxanthine (IBMX), nitric oxide donors, and bicyclic monoterpene (BMT) diols. These agents are compared with regards to efficacy when administered to melanoma cells, normal human epidermal melanocytes, animal skin, and human skin. In addition, mechanisms of action are reviewed since these may reveal issues related to both efficacy and safety. Both dihydroxyacetone and topically applied melanins are presently available to the consumer, and both of these have been shown to provide some photoprotection. Of the pigmentation stimulators, only PUVA and MSH analogs have been tested extensively on humans, but there are concerns about the safety and side effects of both. At least some of the remaining pigmentation stimulators under development have the potential to safely induce a photoprotective tan.

A prospective study of the incidence of the purple glove syndrome

PURPOSE

Phenytoin (PHT) has been widely used intravenously for the treatment of seizures since 1956, and for many years, it has been considered first-line therapy for status epilepticus. It is routinely administered intravenously in emergency departments and hospitals for patients who have had isolated seizures and for many patients undergoing neurosurgical procedures who are unable to receive oral medication. Adverse reactions from PHT have been widely studied for years, but in the past decade, new adverse reactions have been identified. One of these adverse reactions is the purple glove syndrome (PGS), characterized by edema, discoloration, and pain distal to the site of i.v. administration of PHT. Because there have been no prospective reports of the incidence of PGS, the objective of the study was to report the incidence of this syndrome.

METHODS

We enrolled 179 consecutive exposures to i.v. PHT at Henry Ford Hospital. Distal portions of the upper extremities were examined and digitally photographed by one of the authors (J.G.B.). The photos were blindly evaluated by the third author (G.L.B.) for PGS. Demographic and pertinent medical history was recorded for all patients, and outcome for those who experienced PGS was recorded. Associations between PGS, demographic, and medical history information were assessed.

RESULTS

In only three of the 179 exposures did PGS develop. In both patients, the severity of the clinical picture was mild and did not required prolonged hospitalization or specialized treatment.

CONCLUSIONS

PGS is an infrequent and mild adverse effect of i.v. PHT administration.