Novel secolignans from Peperomia dindygulensis and their inhibitory activities on JAK-STAT signaling pathways.

Nineteen secolignans (1-19), including five new ones (1-5), were isolated from the whole plant of Peperomia dindygulensis. Their structures including stereochemistry were determined by spectroscopic methods, in particular NMR and electronic CD (ECD) analysis. All the isolates were evaluated for their inhibitory activities against IFN-γ/STAT1 as well as IL-6/STAT3 signaling pathway by the method of Luciferase assay.

Active components with inhibitory activities on IFN-γ/STAT1 and IL-6/STAT3 signaling pathways from Caulis Trachelospermi.

Initial investigation for new active herbal extract with inhibiting activity on JAK/STAT signaling pathway revealed that the extract of Caulis Trachelospermi, which was separated by 80% alcohol extraction and subsequent HP-20 macroporous resin column chromatography, was founded to strongly inhibit IFN-γ-induced STAT1-responsive luciferase activity (IFN-γ/STAT1) with IC50 value of 2.43 μg/mL as well as inhibiting IL-6-induced STAT3-responsive luciferase activity (IL-6/STAT3) with IC50 value of 1.38 μg/mL.