The importance of natural product characterization in studies of their anti-inflammatory activity

The knowledge that natural products provide a rich source for therapeutic discovery has led to the development of many of the world's most commonly used drugs. In view of the growing need for effective anti-inflammatory agents, the potential for natural products to serve as safe and effective therapeutic agents has gained increasing attention. However, polymolecular extracts must be rigorously evaluated and chemically characterized to insure adequate consistency in performance. The research in this field has been plagued by inconsistencies due in part to inadequate chemical characterization and documentation, making comparison of results across studies very difficult. Analytical chemistry and molecular methods now exist to insure sufficient transparency to avoid this limitation. Further, our understanding of the complexity of inflammation has advanced to enable significant insight into the mechanism of action of these natural extracts. Here, we review the inflammatory pathways targeted by many therapeutic agents, discuss the value of natural products as anti-inflammatory agents, review approaches for their biological and chemical evaluation, and highlight challenges to the field. We present two examples highlighting the rigorous use of cell, molecular, and chemical methods for characterization and quality control as templates for future studies of anti-inflammatory activity of natural products.