(826.2) A High-Through Put Pro-inflammatory screening of natural products using mouse RAW 264.7 macrophages indicate a more significant number of pro-inflammatory natural herbal products than anti-inflammatory

Poster Board Number: D20

Andrew Barnes (Florida Aamp;M University), Elizabeth Mazzio (Florida Aamp;M University), Ramesh Badisa (Florida Aamp;M University), Karam Soliman (Florida Aamp;M University)

When it comes to natural product research, there are an overarching plethora of studies focusing on and reporting "antioxidant" and "anti-inflammatory properties," with a relative void in the literature elucidating those that have pro-inflammatory (immune stimulating) and pro-oxidant properties. Furthermore, when it comes to cancer study, many anti-cancer compounds induce apoptosis in the same cell lines (e.g., RAW 264.7 and BV-2 cells) used to model inflammation, creating a confounding variable [cell death] leading to false positives for reported anti-inflammatory compounds. We tested over 1,400 natural products in our past work and found only 29 confirmed natural anti-inflammatory compounds effective against LPS treated RAW 264.7 viable cells. In the present study, we are reporting (without a confounding variable of cell death and with matrix controls run for every extract) an enormous number; 444 natural products to evoke pro-inflammatory effects in RAW 264.7 cells producing nitric oxide at levels equal to LPS and IFN-g, using the same library. We found these herbs capacity to induce IFN-g, whereas IFN-g by itself can induce iNOS, defining the general mechanism of action. These findings suggest that many natural products trigger a massive elevation in IFN-g by immune-competent cells such as macrophages and could either worsen auto-immune or inflammatory conditions or stimulate the immune system to fight infections when needed. In conclusion: there needs to be more work in the pro-inflammatory/immune stimulation aspects of herbs and the specific influence of natural products on various immune cells and processes. It was concluded that in cancer cells, the anti-inflammatory /antioxidant compounds might likely prevent cancer, but once cancer is established, pro-inflammatory/ pro-oxidant compounds may be required to re-establish immunosurveillance.

This research was supported by NIH Grants U54 MD007582 and P20 MD 006738.