Platelet function in cutaneous diseases

Abstract

Blood platelets participate actively in immune-inflammatory processes. Responding to the variety of stimuli such as cell activation leads to the release of several mediators, including RANTES, platelet factor 4, beta-thromboglobulin, thymus and activation-regulated chemokine (TARC/CCL17), serotonin and arachidonic acid metabolites. It also affects the expression of immunomodulatory and adhesive molecules, including CD154 and P-selectin. Immune-inflammatory processes associated with skin diseases could induce platelet activation, which, in turn, would contribute to acceleration and modulation of these processes. Activated platelets are capable of facilitating leukocyte rolling in the skin and the release of skin inflammation mediators. Changes in platelet function and behaviour may occur in certain types of skin inflammatory conditions and platelets might then be an important effector cell of the skin immune system, contributing to the pathogenesis of some skin inflammatory disorders. The changes in platelet activity and reactivity have been demonstrated to show distinctly different pathogenic mechanisms in cutaneous diseases, such as urticaria, atopic eczema/dermatitis syndrome and psoriasis. Considering the risk of cardiovascular events, some of them seem to be of clinical significance. This contribution is a brief outline of the present knowledge of the platelet function in dermal disorders.

Mean platelet volume, neutrophil to lyphocyte ratio and platelet to lymphocyte ratio in psoriasis

“…Aynı zamanda N/L ve T/L oranlarının eritrosit sedimentasyon hızı (ESH), C-reaktif protein (CRP) ve psoriasis patogenezinde de önemli rol oynayan interlökin-6 (IL-6) ve tümör nekrozis faktör-alfa (TNF-alfa) değerleriyle ilişki gösterdiği tespit edilmiştir [7][8][9][10] . Diğer inflamatuvar hücrelerle beraber trombositlerin de psoriasis patogenezinde rol oynadığı ve aktive olmuş trombositlerin deriye lökosit göçünü arttırıp deride inflamatuvar sitokinlerin salınımını arttırdığı düşünülmektedir 11 . Ortalama trombosit hacmi (OTH); trombosit fonksiyonu ve aktivasyonunun bir göstergesi olarak kabul edilmekte ve yüksek OTH değerlerinin akut miyokard enfarktüsü, renal arter stenozu, dibetes mellitus, hipertansiyon ve hiperlipidemi için bağımsız bir risk faktörü olduğu gösterilmiştir.…”

Evaluation of Mean Platelet Volume in Patients with Pigmented Purpuric Dermatosis

“…Kontakt dermatitin kompleks etyopatogenezinde gecikmiş tip hipersentivite üzerinde rolü olan trombositlerde yer almaktadır. Trombositlerin kutanöz hastalıklar da birçok farklı mekanizma yoluyla patogeneze katkıda bulunabileceği düşünülmüş-tür (6,15,16).…”

“…Psoriasis, atopik dermatit, kontakt dermatit ve ürtiker gibi bazı kutanöz hastalıklarda trombositlerin hastalıktaki rolünü araştıran çalışmalar mevcuttur (6 …”

An investigation of the relationship between serotonin transporter gene promoter polymorphism and psoriasis susceptibility in a Thai population

“…Fundamentally, 5-HT is not only synthesized by enterochromaffin cells of the gut and the serotonergic neurons of the brain, but also other cells including lymphocytes (O'Connell et al, 2006). Since 5-HT is accumulated in the platelets and released at inflammatory sites (Geba et al, 1996) and platelet functions have been shown to be associated with dermal diseases (Kasperska-Zajac et al, 2008), the potential participation of 5-HT in psoriasis is strongly supported. Based on the experimental evidence that stress and stress-related hormones promote 5-HT synthesis (Azmitia Jr. and McEwen, 1969;Azmitia et al, 1993), 5-HT may therefore serve as a critical mediator in a neuro-immunocutaneous-endocrine model (O'Sullivan et al, 1998).…”