Indirubin, an acting component of indigo naturalis, inhibits EGFR activation and EGF-induced CDC25B gene expression in epidermal keratinocytes

Effect of psoriasis activity on epidermal growth factor (EGF) and the concentration of soluble EGF receptor in serum and plaque scales

“…The abnormal histological features of psoriatic tissue can be ameliorated with antibodies to EGFR . As shown recently by Hsieh et al ., activation of EGFRs in psoriatic lesions can be inhibited by indirubin and thus ameliorate epidermal keratinocyte proliferation. Recently described cases of successful treatment with EGFR inhibition resulting in complete resolution of psoriatic lesions has encouraged research into new EGFR inhibitors designed exclusively for the treatment of psoriasis …”

“…Binding of the EGFR receptor to monoclonal antibodies or inhibitors can ameliorate proliferation of keratinocytes . These substances are capable of binding EGF, and thereby preventing proliferative signal transduction, which can be a clinically relevant strategy for the inhibition of keratinocyte hyperplasia . By contrast, activation of EGFR by EGF and transforming growth factor (TGF)‐α upregulates production of Decoy receptor (Dcr)3, which has a pleiotropic role in many inflammatory and autoimmune disorders and malignant diseases .…”

“…13,14 These substances are capable of binding EGF, and thereby preventing proliferative signal transduction, which can be a clinically relevant strategy for the inhibition of keratinocyte hyperplasia. 15 By contrast, activation of EGFR by EGF and transforming growth factor (TGF)-a upregulates production of Decoy receptor (Dcr)3, which has a pleiotropic role in many inflammatory and autoimmune disorders and malignant diseases. 16 However, there are limited data currently available on the role of EGF and sEGFR in the pathogenesis of psoriasis and the possible application of their measurement in psoriasis management.…”

Indirubin: a novel topical agent in the treatment of psoriasis

“…Indirubin is thought to have its effect in psoriasis via inhibition of cell proliferation and induction of cell differentiation. It has been found to inhibit cell‐cycle‐related kinases, inhibit cell‐signalling proteins such as STAT3, interact with the aryl hydrocarbon receptor, inhibit pathological angiogenesis, and inhibit the production of various proinflammatory cytokines such as interferon‐γ …”

Comparison of indirubin concentrations in indigo naturalis ointment for psoriasis treatment: a randomized, double‐blind, dosage‐controlled trial

“…Our previous studies showed that indigo naturalis repairs the abnormal epidermal barrier by promoting differentiation, upregulating claudin‐1 expression, restoring tight junction proteins and inhibiting keratinocyte proliferation . In addition, there is evidence that indigo naturalis and indirubin (the active component of indigo naturalis) inhibit activation of epidermal growth factor receptor, which is known to contribute to psoriasis pathogenesis . Indirubin may also suppress skin inflammation through inhibition of cytokines production, nuclear factor kappa B activity and mitogen activated protein kinase activation …”