Intralesional photodynamic therapy induces apoptosis in basal cell carcinoma and Bowen's disease through caspase 3 and granzyme B.

Background: Photodynamic therapy (PDT) is used to treat cutaneous cancers. It may induce cell death through direct and indirect means, including apoptosis, inflammation and certain immune mechanisms, with the depth of penetration as a potential modifying factor.

Objectives: To examine the pathways of apoptosis in the intralesional PDT of basal cell carcinoma (BCC) and intraepidermal squamous cell carcinoma (Bowen's disease).

Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation.

Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin levels in the skin of healthy volunteers after consumption of green tea and how catechins in the plasma are related to their presence in skin tissue samples.

High performance liquid chromatography tandem mass spectrometry dual extraction method for identification of green tea catechin metabolites excreted in human urine.

The simultaneous analysis of free-form and conjugated flavonoids in the same sample is difficult but necessary to properly estimate their bioavailability. A method was developed to optimise the extraction of both free and conjugated forms of catechins and metabolites in a biological sample following the consumption of green tea. A double-blind randomised controlled trial was performed in which 26 volunteers consumed daily green tea and vitamin C supplements and 24 consumed a placebo for 3 months.

Sunlight exposure and photoprotection behaviour of white Caucasian adolescents in the UK.

Background: Sun exposure has positive and negative effects on health, yet little is known about the sun exposure behaviour of UK adolescents, including those more prone or less prone to sunburn.

Objective: To examine sun exposure behaviour of UK white Caucasian adolescents including time spent outdoors, holiday behaviour, use of sunscreen and clothing, with assessment for differences between sun-reactive skin type groups.

Methods: White Caucasian adolescents (12-15 years) attending schools in Greater Manchester completed a two-page questionnaire to assess sun exposure and photoprotective behaviour.

Impact of EPA ingestion on COX- and LOX-mediated eicosanoid synthesis in skin with and without a pro-inflammatory UVR challenge--report of a randomised controlled study in humans.

Scope: Eicosapentaenoic acid (EPA), abundant in oily fish, is reported to reduce skin inflammation and provide photoprotection, potential mechanisms include competition with arachidonic acid (AA) for metabolism by cyclooxygenases/lipoxygenases to less pro-inflammatory mediators. We thus examine impact of EPA intake on levels of AA, EPA and their resulting eicosanoids in human skin with or without ultraviolet radiation (UVR) challenge.

Methods And Results: In a double-blind randomised controlled study, 79 females took 5 g EPA-rich or control lipid for 12 wk.

Oral green tea catechin metabolites are incorporated into human skin and protect against UV radiation-induced cutaneous inflammation in association with reduced production of pro-inflammatory eicosanoid 12-hydroxyeicosatetraenoic acid.

Green tea catechins (GTC) reduce UV radiation (UVR)-induced inflammation in experimental models, but human studies are scarce and their cutaneous bioavailability and mechanism of photoprotection are unknown. We aimed to examine oral GTC cutaneous uptake, ability to protect human skin against erythema induced by a UVR dose range and impact on potent cyclo-oxygenase- and lipoxygenase-produced mediators of UVR inflammation, PGE2 and 12-hydroxyeicosatetraenoic acid (12-HETE), respectively. In an open oral intervention study, sixteen healthy human subjects (phototype I/II) were given low-dose GTC (540 mg) with vitamin C (50 mg) daily for 12 weeks.

Ultraviolet radiation-induced upregulation of antimicrobial proteins in health and disease.

This article reviews recent data on the expression, regulation and activation of antimicrobial peptides (AMP) in human skin, and considers their potential protective and pro-inflammatory roles following upregulation by ultraviolet radiation (UVR). Antimicrobial peptides are small peptides that are key components of the innate immune system, originally identified by their vital role in protecting the body-environment interface from infection. However, it has now become clear that AMP have more extensive actions, including the provision of pivotal links with the adaptive immune system.

Topical aminolaevulinic acid-photodynamic therapy produces an inflammatory infiltrate but reduces Langerhans cells in healthy human skin in vivo.

Background: Topical photodynamic therapy (PDT) elicits a therapeutic response in both skin cancer and immune-mediated skin disorders. While PDT induces direct cell death, host inflammatory and immune responses to PDT may contribute to the therapeutic effects.

Objectives: To examine the impact of topical PDT on leucocyte trafficking and mediators of chemotaxis in healthy human skin.

Omega-3 polyunsaturated fatty acids: photoprotective macronutrients.

Ultraviolet radiation (UVR) in sunlight has deleterious effects on skin, while behavioural changes have resulted in people gaining more sun exposure. The clinical impact includes a year-on-year increase in skin cancer incidence, and topical sunscreens alone provide an inadequate measure to combat overexposure to UVR. Novel methods of photoprotection are being targeted as additional measures, with growing interest in the potential for systemic photoprotection through naturally sourced nutrients.

Positive response of a recurrent keloid scar to topical methyl aminolevulinate-photodynamic therapy.

A 36-year-old Caucasian female of Iranian origin presented with a persistently raised dermal lesion under her chin, confirmed histologically to be a keloid scar. There was a 4-year history of a negative response to a range of conventional treatments including topical silicone gel sheets, steroid creams, steroid injections and surgical excision. In view of treatment failure and an in vitro study indicating a positive effect of photodynamic therapy (PDT)on keloid fibroblasts, we treated our patient's lesion with five sessions of methyl aminolevulinate photodynamic therapy (MAL-PDT) over a period of 5 months.

The impact of photosensitivity disorders on aspects of lifestyle.

Background: Photosensitivity disorders involve an abnormal skin reaction to sunlight exposure and affect a substantial percentage of the population. No previous studies have directly compared lifestyle attributes between photosensitive and healthy individuals.

Objectives: To assess the impact of photosensitivity on time spent outdoors in the U.

Recommended summer sunlight exposure levels can produce sufficient (> or =20 ng ml(-1)) but not the proposed optimal (> or =32 ng ml(-1)) 25(OH)D levels at UK latitudes.

Recommendations on limitation of summer sunlight exposure to prevent skin cancer may conflict with requirements to protect bone health through adequate vitamin D levels, the principal source being UVB in summer sunlight. We determined whether sufficient (> or =20 ng ml(-1)) and proposed optimal (> or =32 ng ml(-1)) 25(OH)D levels are attained by following UK guidance advising casual short exposures to UVB in summer sunlight, and performed the study under known conditions to enhance the specificity of future recommendations. During wintertime, when ambient UVB is negligible, 120 white Caucasians, aged 20-60 years, from Greater Manchester, UK (53.

The sunburn response in human skin is characterized by sequential eicosanoid profiles that may mediate its early and late phases.

Sunburn is a commonly occurring acute inflammatory process, with dermal vasodilatation and leukocyte infiltration as central features. Ultraviolet (UV) B-induced hydrolysis of membrane phospholipids releases polyunsaturated fatty acids, and their subsequent metabolism by cyclooxygenases (COXs) and lipoxygenases (LOXs) may produce potent eicosanoid mediators modulating different stages of the inflammation. Our objective was to identify candidate eicosanoids formed during the sunburn reaction in relation to its clinical and histological course.