Search

Low-density lipoprotein-related receptors 5 and 6 ( LRP5/6) are transmembrane receptors with key functions in canonical Wnt signalling. Wnt ligands are thought to play an important role in innate immunity and psoriasis, and recent studies assigned LRP5/6 anti-inflammatory properties. The objective of this study was to investigate the expression of LRP5 and LRP6 in lesional and non-lesional skin in peripheral blood and in mononuclear cells of patients with chronic plaque type psoriasis compared with control individuals. To investigate the effect of UV-B radiation, LRP5/6 skin gene expression was analysed before and after narrowband UV-B treatment. Our results showed significantly decreased gene expression of LRP5 and LRP6 in lesional skin and in peripheral blood from patients with psoriasis compared with non-lesional skin and healthy control skin. Immunohistochemistry did not reveal differences in protein expression of LRP5/6. Narrowband UV-B treatment induced a significant increase in LRP5 and LRP6 gene expression in lesional skin. Decreased gene expression of LRP5/6 in lesional skin and upregulation after nb UV-B treatment suggest a possible role for LRP5/6 in psoriasis. [ABSTRACT FROM AUTHOR]

Findings of recent studies have demonstrated modulation of Wnt/β-catenin signalling by Wnt5a, which is highly expressed in hair follicular dermal papilla ( DP) in vivo. Here, we investigated the question of whether Wnt5a can affect canonical Wnt/β-catenin signalling in DP cells. Treatment with Wnt5a resulted in attenuation of Wnt3a-mediated elevation of β-catenin signalling, which was increased by Wnt5a si RNA transfection in cultured DP cells, as examined by reporter assay. In addition, treatment with Wnt5a resulted in repressed Wnt3a-mediated expression of Axin2, EP2 and LEF1 in cultured DP cells, whereas Wnt5a si RNA transfection resulted in increased Wnt3a-mediated expression of the genes in isolated DPs of cultured hair follicles. Moreover, treatment with Wnt5a resulted in attenuation of Wnt3a-mediated accumulation of β-catenin in the nucleus in DP cells. Our data strongly suggest that Wnt5a acts as an autocrine factor and attenuates canonical Wnt signalling pathway in human DP cells. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the potential augmentation of canonical Wnt/β-catenin signalling in cultured dermal papilla (DP) cells in secreted frizzled-related protein 2 (SFRP2).