Psoriasis environmental factors

Many skin disorders are associated with at least one of the characteristics of inflammation, oxidative stress, hyperproliferation, hypodifferentiation, infection, apoptosis, and autoimmune reactions. GTPs are uniquely positioned to antagonize these conditions with anti-inflammatory, antioxidant, antimicrobial, prodifferentiation, anti-apoptosis, and inhibition of autoantigen properties. Thus, many skin conditions, including autoimmune-induced lupus and psoriasis, wounds created by trauma or infections, damage induced by environmental factors such as UVB, and seborrheic dermatitis (dandruff), could be treated or managed by topical application of GTPs. 

Dry, scaly skin is characterized by a decrease in the water retention capacity of the stratum corneum (SC),1 with water content diminished to less than 10%. Barrier function of the SC is usually declined, and transepidermal water loss (TEWL) is increased because of an abnormality on barrier homeostasis.2 People feel tightness of their skin, and the skin surface becomes rough, scaly, and sensitive. Hyperkeratosis, abnormal scaling, and epidermal hyperplasia are usually observed in the dry skin.2 Keratinization also shows abnormal features.2 These phenomena are commonly observed in atopic dermatitis and psoriasis.3 Dermatitis induced by environmental factors such as exposure to chemicals, low humidity, and UV radiation also shows these features. Thus, many researchers have been investigating the cause and treatment of dry skin, and there is currently great interest in adequate model systems for dry skin studies. In this chapter, I will describe several model systems of dry skin for clinical research of dermatitis associated with skin surface dryness and also mention recent studies to improve the dry skin. 

Psoriasis is a complex and multifactorial disease due to the interaction between environmental factors (exogenous or endogenous antigens) and a specific genetic background. The antigens involved in disease development are not completely known or understood. ... 

The disease appears to have a genetic basis with environmental factors, such as infections, emotional trauma or mechanical trauma, causing outbreaks in susceptible individuals. Psoriasis should be regarded as a chronic systemic disease, which can be associated with other chronic diseases such as heart disease, hypertension and diabetes and may reduce life expectancy. About 15% of people with psoriasis also have psoriatic arthritis (see Chapter 7, page 173). 

Psoriasis is a T-lymphocyte-mediated inflammatory disease that results from a complex interplay between multiple genetic factors and environmental influences. Genetic predisposition coupled with some precipitating factor triggers an abnormal immune response, resulting in the initial psoriatic skin lesions. Keratinocyte proliferation is central to the clinical presentation of psoriasis. 

The medical history of a patient with psoriasis should include information about the onset and duration of lesions, family history of psoriasis, presence of exacerbating factors, previous history of antipsoriatic treatment (if any) along with efficacy and adverse effect data, exposure to chemicals and toxins, and allergies (food, drugs, and environmental). 

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