Psoriasis: Molecular targets of denervation and therapy

In this thesis global transcriptomic effects of denervation were analyzed in unique cases showing unilateral resolution of psoriasis occurred following surgical denervation (chapter 2). In our studies, we focused on the epidermis, as this forms the main innate defence barrier of the skin. We analysed global transcriptomic effects of surgical denervation in a murine psoriasiform model (chapter 3). Because the contribution of neuromediators to innate defence is mostly unknown, we investigated the effects of SP, CGRP, and VIP on the epidermal expression of TLR and host defence peptides in an ex vivo skin explant model (chapter 4). The molecular epidermal targets of recombinant IL-4 in ex vivo stimulated biopsies from psoriatic and healthy skin were investigated (chapter 5). Furthermore, the effect of the biologic ustekinumab (anti IL-12/IL-23) on epidermal molecular markers of innate defence in uninvolved skin of patients with psoriasis was investigated (chapter 6). The following main conclusions were drawn: Denervation affected genes involved in epidermal barrier function, and TLR function, as the inflammatory response to the TLR7 ligand imiquimod is prevented in denervated skin. Denervation inhibited cutaneous CGRP expression and prevented the enhanced expression of CGRP by imiquimod. Ex vivo stimulation of skin with GCRP results in enhanced expression of epidermal TLR9. Established treatments reach beyond the dermal infiltrate and also target keratinocytes: IL-4 and ustekinumab therapy increase GATA3, which is a transcription factor critical for epidermal homeostasis, and down-regulate NGF expression, which is linked to inflammatory conditions

GATA3 Expression Is Decreased in Psoriasis and during Epidermal Regeneration; Induction by Narrow-Band UVB and IL-4

Psoriasis is characterized by hyperproliferation of keratinocytes and by infiltration of activated Th1 and Th17 cells in the (epi)dermis. By expression microarray, we previously found the GATA3 transcription factor significantly downregulated in lesional psoriatic skin. Since GATA3 serves as a key switch in both epidermal and T helper cell differentiation, we investigated its function in psoriasis. Because psoriatic skin inflammation shares many characteristics of epidermal regeneration during wound healing, we also studied GATA3 expression under such conditions

Cellular and molecular effects of pulsed dye laser and local narrow-band UVB therapy in psoriasis

BACKGROUND AND OBJECTIVES: Pulsed dye laser (PDL) therapy is effective in clearing psoriasis plaques, but the mechanism of action is only partially understood. Local narrow-band ultraviolet B (NB-UVB), which has a better-defined mode of action, is an effective standard treatment for psoriasis. Our aim was to evaluate the cellular and molecular effects of PDL and to compare them with those of local NB-UVB in order to gain further insight into their mechanisms of action in psoriasis. STUDY DESIGN/PATIENTS AND METHODS: Nineteen patients with stable plaque-type psoriasis were treated either with PDL or NB-UVB. Lesional punch biopsies were obtained from all patients before treatment. Additional biopsies were obtained at 3 and 24 hours after PDL treatment in five of these patients. In 14 patients additional biopsies were taken after 7 and 13 weeks of treatment. Samples were histopathologically examined for the level of dermal T cell infiltrate, and the expression of epidermal beta-defensin 2, immune cell-derived tumor necrosis factor (TNF)-alpha, endothelial E-selectin, vascular endothelial growth factor receptor (VEGFR) 2 and 3, and the expression of interleukin (IL)-23 before and after treatment. RESULTS: The expression of VEGFR2, VEGFR3, and E-selectin was decreased in clinically high responders within 24 hours after PDL treatment. The expression of IL-23, TNF-alpha mRNA, and E-selectin protein were significantly reduced after two PDL treatments, whereas the expression of all epidermal markers and dermal T cell infiltrates had normalized after four treatments. The expression of epidermal activation markers and E-selectin were significantly reduced after 13 weeks of NB-UVB treatment. CONCLUSIONS: The expression of epidermal activation markers and the dermal T cell infiltrates were decreased after both treatments. The decreased expression of VEGFR2 and VEGFR3 followed by the down-regulation of TNF-alpha and IL-23p19 may be contributory factors in the efficacy of PDL in stable plaque-type psoriasis

Is Telemedicine Suitable for Patients with Chronic Inflammatory Skin Conditions? A Systematic Review

Telemedicine, the provision of remote healthcare, has gained prominence, accelerated by the COVID-19 pandemic. It has the potential to replace routine in-person follow-up visits for patients with chronic inflammatory skin conditions. However, it remains unclear whether telemedicine can effectively substitute in-person consultations for this patient group. This systematic review assessed the effectiveness and safety of telemedicine compared with traditional in-person care for chronic inflammatory skin diseases. A comprehensive search in various databases identified 11 articles, including 5 randomized controlled trials (RCTs) and 1 clinical controlled trial (CCT). These studies evaluated telemedicine’s impact on patients with psoriasis and atopic dermatitis, with varying methods like video consultations and digital platforms. The findings tentatively suggest that telemedicine does not seem to be inferior compared with in-person care, particularly in terms of condition severity and quality of life for patients with chronic inflammatory skin diseases. However, these results should be interpreted with caution due to the inherent uncertainties in the evidence. There are indications that telemedicine can offer benefits such as cost-effectiveness, time savings, and reduced travel distances, but it is important to recognize these findings as preliminary, necessitating further validation through more extensive research