Modulatory effects of Echinacea purpurea extracts on human dendritic cells: A cell- and gene-based study
Herbal medicine has been empirically used for treating diseases or improving the immune system for ages. However, until recently, little or no systematic evidence-based research into a series of anecdotally claimed effects was performed, and as a result, clear demonstrations of pharmacological efficacy were often not available. Echinacea purpurea, also known as purple coneflower, has become a top-selling medicinal herb and food supplement in Europe and the United States. Dendritic cells (DCs) are professional antigen-presenting cells that play a key role in mediating activities of various immune systems, including primary innate immune responses and T-cell-mediated immune responses. In this study, we developed an oligonucleotide-based array system to evaluate the differential gene expression patterns in human immature DCs (imDCs) in response to the immunomodulatory activities of phytocompounds from E. purpurea. Our results show that root [R] and stem plus leaf [S+L] tissue extracts of E. purpurea exhibit opposite (enhancing vs. inhibitory) modulatory effects on the expression of the CD83 marker in human DCs. Down-regulation of mRNA expression of specific chemokines (e.g., CCL3 and CCL8) and their receptors (e.g., CCR1 and CCR9) was observed in [S+L]-treated DCs. Other chemokines and regulatory molecules (e.g., CCL4 and CCL2) involved in the c-Jun pathway were found to be up-regulated in [R]-treated DCs. This study, for the first time, demonstrates that E. purpurea extracts can modulate DC differentiation and expression of specific immune-related genes in DCs.
Modulatory effects of Echinacea purpurea extracts on human dendritic cells: A cell- and gene-based study
