Postinflammatory hyperpigmentation (PIH) is a common problem in darker skin types and happens after injury or inflammatory dermatoses such as acne vulgaris. The authors sought to create a reproductible model in humans after inducing PIH on the trunk with trichloracetic acid 35% (TCA 35%) and comparing it with PIH induced by truncal acne. 4 patients…
Soy contains antioxydants calles isoflavones. The 2 main ones are genistein and daizedine. In this study, the authors studied 7,3’,4’-Trihydroxyisoflavone (7,3’,4’-THIF), a metabolite of daidzedine would have a depigmenting effect Contrarily to daizedine, 7,3’,4’-THIF inhibits the extracellular and intracellular production of melanin by B16F10 cells (induced by α-melanocyte-stimulating hormone (MSH)) (7,3’,4’-THIF), abolished the expression of…
The authors constructed the molecular regulatory network of melanogenesis by focusing on 2 pathways: paracrine factor-mediated signaling pathway Microphthalmia-associated transcription factor-related pathway By reviewing the literature, the authors established a “Boolean network model” that describes the dynamical characteristics of the network: Molecules which would decrease pigmentation: CREB, MITF protein, MITF active, GSK3B, CAMP, AC, PKA,…
Solar lentigo (sunspots, liver spots) are early seborrheic keratosis and are found in many individuals starting 45-50 years old. They are the result of sun exposure (photodamage). The goal of this study is to investigate the link between fat intake and the severity of solra lentigo. The study was done in 279 women: The severity…
Smoking tobacco is known for inducing skin pigmentation. In vitro the authors cultures human epidermal melanocytes. When cultured with tobacco smoke extract: Pigment cells (melanocytes) grew to a large size and produced more melanin. Some melanocytes were irradiated with UVB light (another cause of pigmentation), and a similar production of melanin was observed. However the…
Triple Combination Creams (Triluma) In Melasma (Hydroquinone, Fluocinolone, Tretinoin) Don’t Always Work. Triple combination creams are considered to be the gold standard in the treatment of melasma (chloasma, pregnancy mask). As a general rule, topical treatments work best when the location of the pigment is superficial. On the other hand, treatment with light sources are…
Peri-orbital dark circles (DUEC) are a cosmetic concern worldwide and numerous causes and risk factors have been advocated as playing a role: allergy atopic dermatitis blood stasis structural shadowing effects a thinner epidermis/dermis under the eye. Questionnaires were given to 495 Brazilian women and the severity of DUEC was evaluated by a dermatologist. Hyperspectral image…
Although still poorly understood, theories to the etiology of vitiligo are emerging. One of them is mitochondrial dysfunctioning which would lead to oxydative stress and destruction of the melanocytes (pigment cells, unable to renew themselves). More precisely an increased Cyclosporin A-dependent ROS production, associated with a loss of membrane potential (Δψm), and defective Complex I…
This tool is mainly used in research for measuring severity in patients who have melasma (chloasma, pregnancy mask). It would be useful in the measurement of the melasma before and after a treatment for example. Its measurement relies on the measurement in 4 areas: (F) forehead which accounts for 30% of the score (RMR) right…
Concept of the Skin pull test. Pinch the skin on the forearm. Then pull on it. In a young person, the skin goes back to normal within 1 second. In an individual over 50*, it takes 5 seconds or more. This is due to the loss of collagen, elasticity etc… *With a strong exposure to…
