Melasma is a common acquired symmetric hypermelanosis characterized by irregular light to dark brown macules and patches on sunexposed areas of the skin. Its histopathologic characteristics are important for treatment. Melasma is characterized by epidermal hyperpigmentation possibly by both the increased number of melanocytes and the increased function of melanogenic enzymes over the dermal solar changes. Until now, curative measures are not available for melasma. Current therapies include topical agents (retinoic acid, hydroquinone, steroids), peeling (Combes solution, glycolic acid, TCA), and lasers(Co2, Erbium-Yag, Q-switched).
Hyperpigmentation ; Melanocytes ; Melanosis* ; Skin ; Skin Lightening Preparations

OBJECTIVE: To investigate the different treatment modalities employed for melasma by practicing dermatologists in the Philippines. BACKGROUND: Melasma is a prevalent skin condition among Filipinos due to our skin type and climate. To date, no local studies have been done investigating the different treatment regimens practiced/ employed by Filipino dermatologists in treating melasma. METHODS: This is a descriptive study investigating the different treatment strategies used by Filipino dermatologists using a questionnaire.The questionnaires were given to practicing Filipino dermatologists personally during conferences and conventions held in 2005 as well as to the different Philippine Dermatological Society accredited training institutions and private clinics of the doctors. The total sample size was 117. RESULTS: Melasma is frequently seen among Fitzpatrick skin type IV (50%),females, 41-50 year-old age group (50%) and commonly on the cheeks (98%). Grade 2 severity melasma was often seen by 75% of the respondents. The top 3 topical depigmenting agents of choice are tretinoin, hydroquinone and combination therapy. Microdermabrasion was preferred by 43.5% of the respondents over laser. Once combination treatment regimens fail, laser treatment more than doubled to 28.7%. Vitamin C (37.7%) and glutathione (31.6%) are the most common oral maintenance therapy given by the respondents. Half of all the respondents advise continuous maintenance therapy while a third of them advise maintenance for a year. The most common side effect of melasma treatment is erythema according to 51% of the respondents followed largely by hyperpigmentation (23%) and scaling (22%). More than half of the dermatologists surveyed stop the treatment regimen when side effects are observed. Almost all respondents advise patients to use sunblock daily and majority of respondents prescribe both UVB and UVA sunblocks.

Human ; Female ; Ascorbic Acid ; Cheek ; Dermatologists ; Erythema ; Glutathione ; Hydroquinones ; Hyperpigmentation ; Melanosis ; Philippines ; Skin Lightening Preparations ; Sunscreening Agents ; Surveys And Questionnaires ; Tretinoin

The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy) methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent.
Animals ; Antlers ; Cornus ; Hypopigmentation ; MAP Kinase Signaling System ; Melanins* ; Microphthalmia-Associated Transcription Factor ; Monophenol Monooxygenase ; Phosphotransferases ; Skin Lightening Preparations ; Skin* ; Skin, Artificial

BACKGROUND/OBJECTIVES: Gastrodia elata Blume (GEB), a traditional herbal medicine, has been used to treat a wide range of neurological disorders (e.g., paralysis and stroke) and skin problems (e.g., atopic dermatitis and eczema) in oriental medicine. This study was designed to investigate whether GEB extract inhibits melanogenesis activity in murine B16F10 melanoma. MATERIALS/METHOD: Murine B16F10 cells were treated with 0-5 mg/mL of GEB extract or 400 µg/mL arbutin (a positive control) for 72 h after treatment with/without 200 nM alpha-melanocyte stimulating hormone (α-MSH) for 24 h. Melanin concentration, tyrosinase activity, mRNA levels, and protein expression of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein (Trp)1, and Trp2 were analyzed in α-MSH-untreated and α-MSH-treated B16F10 cells. RESULTS: Treatment with 200 nM α-MSH induced almost 2-fold melanin synthesis and tyrosinase activity along with increased mRNA levels and protein expression of MITF, tyrosinase, Trp1 and Trp2. Irrespective of α-MSH stimulation, GEB extract at doses of 0.5-5 mg/mL inhibited all these markers for skin whitening in a dose-dependent manner. While lower doses (0.5-1 mg/mL) of GEB extract generally had a tendency to decrease melanogenesis, tyrosinase activity, and mRNA levels and protein expression of MITF, tyrosinase, Trp1, and Trp2, higher doses (2-5 mg/mL) significantly inhibited all these markers in α-MSH-treated B16F10 cells in a dose-dependent manner. These inhibitory effects of the GEB extract at higher concentrations were similar to those of 400 µg/mL arbutin, a well-known depigmenting agent. CONCLUSIONS: These results suggest that GEB displays dose-dependent inhibition of melanin synthesis through the suppression of tyrosinase activity as well as molecular levels of MITF, tyrosinase, Trp1, and Trp2 in murine B16F10 melanoma. Therefore, GEB may be an effective and natural skin-whitening agent for application in the cosmetic industry.
Arbutin ; Dermatitis, Atopic ; Gastrodia* ; Herbal Medicine ; Medicine, East Asian Traditional ; Melanins ; Melanoma* ; Microphthalmia-Associated Transcription Factor ; Monophenol Monooxygenase ; Nervous System Diseases ; Paralysis ; RNA, Messenger ; Skin ; Skin Lightening Preparations

OBJECTIVETo study the possibility of removal melanin granules from autogenic acellular dermal matrix of giant nevus tissue by H2O2 bleaching technique.

METHODSA total of 32 skin specimens (0.5 cm x 0.5 cm) from giant nevus tissue and 1 piece (0.5 cm x 0.5 cm) of normal skin were obtained from the surgical removal. One giant nevus tissue was chosen as control. The others and the normal skin tissue were treated with solution of 0.25% Dispase II for digestion for 24 hours under normal temperature to remove epidermis. Then each piece was immerged into solution of 0.5% Triton X-100 for digestion for 48 hours in normal temperature. One giant nevus tissue and the normal skin tissue were chosen as control. The others were immerged into solution of different concentrations of H2O2, treated under different temperature and lasting for different period. Lastly, all specimens were treated with HE staining, immunohistochemical staining, light microscopy and so on.

RESULTSAfter giant nevus tissues were treated with solution of 0.25% Dispase II and immerged into solution of 0.5% Triton X-100 in normal temperature, nevus cells and all other cellular components of pigmented nevus tissues can be effectively removed, there were the cavities left by removal of cells without any residual cell debris, but still remaining part of pigment. Then each specimen were immerged into solution of different concentrations of H2O2, under different temperature and lasting for different period which can remove residual melanin granules. In solution of 3% H2O2 for 36 h under 37 degrees C, can remove all the melanin particles, the content of collagen type I in the obtained specimen was not changed. Collagen fibers were uniform in thickness, regular in arrangement with no obvious degeneration.

CONCLUSIONSWith solution of 0.25% Dispase II and solution of 0.5% Triton X-100 in normal temperature, all cells in nevus tissue can be removed effectively. Further treatment with 3% H2O2 at 37 degrees C for 36 h can remove all the melanin particles, while collagen type I has no obvious change. The preparation of acellular dermal matrix of the giant nevus may possibly be applied as autologous tissue implant to repair tissue defects.

Acellular Dermis ; Endopeptidases ; pharmacology ; Epidermis ; Humans ; Hydrogen Peroxide ; pharmacology ; Melanins ; Nevus ; pathology ; Nevus, Pigmented ; pathology ; Octoxynol ; pharmacology ; Skin Lightening Preparations ; pharmacology ; Skin Neoplasms ; pathology ; Skin Pigmentation ; drug effects ; Skin Transplantation ; Surface-Active Agents ; pharmacology

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety.
Biological Availability ; Biological Markers/blood/urine ; Blood-Brain Barrier/metabolism ; Body Burden ; Dental Amalgam/chemistry/metabolism ; *Environmental Exposure ; Humans ; Mercury/chemistry/*metabolism ; Mercury Compounds/chemistry/*metabolism ; Skin Lightening Preparations/chemistry/metabolism