icg-001 and Scleroderma--Systemic

The morphogen pathways Hedgehog, Wnt and Notch are attractive targets for antifibrotic therapies in systemic sclerosis. Interference with stem cell regeneration, however, may complicate the use of morphogen pathway inhibitors. We therefore tested the hypothesis that combination therapies with low doses of Hedgehog, Wnt and Notch inhibitors maybe safe and effective for the treatment of fibrosis.. Skin fibrosis was induced by bleomycin and by overexpression of a constitutively active TGF-β receptor type I. Adverse events were assessed by clinical monitoring, pathological evaluation and quantification of Lgr5-positive intestinal stem cells.. Inhibition of Hedgehog, Wnt and Notch signalling dose-dependently ameliorated bleomycin-induced and active TGF-β receptor type I-induced fibrosis. Combination therapies with low doses of Hedgehog/Wnt inhibitors or Hedgehog/Notch inhibitors demonstrated additive antifibrotic effects in preventive as well as in therapeutic regimes. Combination therapies were well tolerated. In contrast with high dose monotherapies, combination therapies did not reduce the number of Lgr5 positive intestinal stem cells.. Combined inhibition of morphogen pathways exerts additive antifibrotic effects. Combination therapies are well tolerated and, in contrast to high dose monotherapies, may not impair stem cell renewal. Combined targeting of morphogen pathways may thus help to overcome dose-limiting toxicity of Hedgehog, Wnt and Notch signalling.

Topics: Amyloid Precursor Protein Secretases; Animals; Bleomycin; Bridged Bicyclo Compounds, Heterocyclic; Disease Models, Animal; Drug Therapy, Combination; Fibrosis; Hedgehog Proteins; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Mice, Transgenic; Protein Serine-Threonine Kinases; Pyrimidinones; Receptor, Transforming Growth Factor-beta Type I; Receptors, Notch; Receptors, Transforming Growth Factor beta; Scleroderma, Systemic; Signal Transduction; Skin; Veratrum Alkaloids; Wnt Proteins; Wnt Signaling Pathway

Fibrosis is a major socioeconomic burden, but effective antifibrotic therapies are not available in the clinical routine. There is growing evidence for a central role of Wnt signalling in fibrotic diseases such as systemic sclerosis, and we therefore evaluated the translational potential of pharmacological Wnt inhibition in experimental dermal fibrosis.. We examined the antifibrotic effects of PKF118-310 and ICG-001, two novel inhibitors of downstream canonical Wnt signalling, in the models of prevention and treatment of bleomycin-induced dermal fibrosis as well as in experimental dermal fibrosis induced by adenoviral overexpression of a constitutively active transforming growth factor (TGF)-β receptor I.. PKF118-310 and ICG-001 were well tolerated throughout all experiments. Both therapeutic approaches showed antifibrotic effects in preventing and reversing bleomycin-induced dermal fibrosis as measured by skin thickness, hydroxyproline content and myofibroblast counts. PKF118-310 and ICG-001 were effective in inhibiting TGF-β receptor I-driven fibrosis as assessed by the same outcome measures.. Blockade of canonical Wnt signalling by PKF118-310 and ICG-001 showed antifibrotic effects in different models of skin fibrosis. Both therapies were well tolerated. Although further experimental evidence for efficacy and tolerability is necessary, inhibition of canonical Wnt signalling is a promising treatment approach for fibrosis.

Topics: Animals; Bridged Bicyclo Compounds, Heterocyclic; Disease Models, Animal; Fibrosis; Mice; Mice, Inbred DBA; Pyrimidinones; Scleroderma, Systemic; Signal Transduction; Skin; Skin Diseases; Treatment Outcome; Triazines; Wnt Signaling Pathway