Novel anti-inflammatory activity of chlorojanerin isolated from Sausurrea heteromalla (D. Don) Hand.-Mazz.. Homo sapiens

Medicinal plants have shown great promise as a source of novel drug compounds for the treatment of inflammatory disorders. In our search for new entities with anti-inflammatory potential, the extracts of the whole plant of Saussurea heteromalla (family-Asteraceae), collected from Himalayas, were evaluated in the high throughput screen for TNF-α and IL-6 inhibitors. The plant has been found as a new source of chlorojanerin, a guaianolide type of sesquiterpene lactone. This is the first report on the potent anti-inflammatory activity of the compound. Chlorojanerin was shown to be significantly effective in inhibiting TNF-α and IL-6 production in LPS induced THP-1 cells (TNF-α, IC50 = 3µM and IL-6, IC50 = 0.8µM). The compound also blocked TNF-α and IL-6 production from LPS induced human monocytes and synovial cells from RA patients. Chlorojanerin also inhibited the binding of NF-κB in a GFP reporter assay system. Transcriptional profiling of the LPS stimulated THP-1 cells revealed that chlorojanerin exerted its anti-inflammatory effect by inhibiting the expression of genes involved in activating the transcription factor – NF-κB. Real time analysis of these genes validated the effect of chlorojanerin on the classical downstream targets of NF-κB. Thus, this study clearly delineated 8 targets specific for the effect of chlorojanerin on NF-κB induced signaling at the mRNA level. This work is a step towards the isolation and characterization of lead anti-inflammatory agents from the extract of Saussurea heteromalla, which can be developed into better therapeutic molecules targeted towards some specific inflammatory diseases. Overall design: Single dye labelling with Cy3 for all treatment RNA samples. Treatments included unstimulated, LPS stimulated, Chlorjanerin treatment and dexamethasone treatment.