Clinical Trial: Diacerin for the Treatment of Epidermolysis Bullosa Simplex

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional




Official Title: Diacerin for the Treatment of Epidermolysis Bullosa Simplex

Brief Summary:

Epidermolysis bullosa simplex type Dowling-Meara (EBS-DM) is one of the most severe subtypes of EBS. Blisters and erosions of the skin and mucous membranes upon minor trauma are the consequence of dominantly inherited mutations in either the keratin 5 (K5) or keratin 14 (K14) gene, which encode proteins constituting the intermediate filament (IF) network in basal keratinocytes . Autosomal dominant mutations lead to a conformational change and an increased self-aggregation of the protein. Upon stress, aggregates present in the periphery of the cytoplasm, subsequently leading to the disintegration and collapse of the IF network. Clinically, patients suffer from blistering of the skin and mucous membranes upon minor trauma, resulting in an impaired life quality due to pain and pruritus . In vitro studies on Dowling-Meara keratinocytes revealed a significant upregulation of the pro-inflammatory cytokine interleukin-1beta (IL-1ß). Apart from paracrine effects of IL-1ß upon wounding (e.g. attraction of lymphocytes, activation of dermal fibroblasts), IL-1ß also activates keratinocytes via the cjun N-terminal kinase (JNK) stress pathway. The activation of this pathway leads to the activation of a number of transcription factors and the enhanced transcription of a number of genes, like matrix metalloproteinases, kallikreins, but also IL-1ß itself and K14 . Interestingly, this state of activation is constitutive and was also found in keratinocytes from non-lesional sites. It seems that the upregulation of IL-1ß and K14 in the presence of dominant Dowling-Meara mutations, results in a positive feedback loop, potentially aggravating the EBS-DM phenotype. This was strongly corroborated by the fact that when impairing IL1ß signaling, using IL-1ß neutralizing antibody (IL-1Ab) or the small molecule diacerein, expression levels of IL-1ß and K14 decreased and keratinocytes were much less susceptibl