The Role of Angiogenesis in the Pathogenesis of Psoriasis: Mechanisms and Clinical Implications
Simon Guérard and Roxane Pouliot*
Centre LOEX de l’Université Laval, Génie tissulaire et régénération : LOEX - Centre de recherche FRSQ du Centre hospitalier affilié universitaire de Québec, Aile-R, 140118e rue, Québec, Québec, Canada, G1J 1Z4 and Faculté de Pharmacie, Université Laval, Québec, Québec, Canada, G1V 0A6.
- *Corresponding Author:
- Roxane Pouliot
Centre LOEX de l’Université Laval
Génie tissulaire et régénération : LOEX - Centre de recherche FRSQ du Centre hospitalier affilié universitaire de Québec
Aile-R, 1401 18e rue, Québec, Québec, Canada, G1J 1Z4
E-mail: [email protected]
Received date: November 09, 2011; Accepted date: January 14, 2012; Published date: January 20, 2012
Citation:Guérard S, Pouliot R (2012) The Role of Angiogenesis in the Pathogenesis of Psoriasis: Mechanisms and Clinical Implications. J Clin Exp Dermatol Res S2:007. doi: 10.4172/2155-9554.S2-007
Copyright: © 2012 Guérard S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Psoriasis is a complex multisystemic skin disease characterized by the recurrent apparition of erythematous plaques often covered by silvery scales. In recent years, the importance attributed to angiogenesis in psoriasis by the scientific community has grown significantly. The vascular network found within these lesions is highly altered, especially in the papillary dermis which is infiltrated by a large number of tortuous and dilated capillaries. Also, endothelial cells composing these vessels are activated and express many adhesion molecules promoting leukocyte recruitment (ICAM-1, VCAM-1, Thy-1, E- and P-selectin). Thus, this pathological angiogenesis is not a mere consequence of the disease, but a key component promoting leukocyte accumulation, inflammation and therefore, skin lesions. This review presents the current understanding and the clinical implications of angiogenesis in psoriasis. Psoriatic skin cells, particularly keratinocytes, promote the expansion of the vascular network through the secretion of pro-angiogenic factors such as VEGF and angiopoietins. Moreover, pro-inflammatory cytokines such as TNF-α, which exert pro-angiogenic action as well as activation of endothelial cells, also contribute to this process. It was demonstrated by in vivo models that angiogenesis, activation of vascular endothelium, inflammation and skin lesions are all closely related in psoriasis. Indeed, angiogenesis promoted by VEGF-secreting keratinocytes leads to local inflammation and skin lesions mimicking psoriasis. From a clinical perspective, most psoriatic treatments have direct, or at least indirect, anti-angiogenic impact, suggesting that their clinical efficacy might be partly explained by these properties. Altogether, these findings identify angiogenesis and the activation of endothelial cells as novel pharmacological targets against psoriasis.