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Preparations of Echinacea (Asteraceae) are frequently consumed for the control and prevention of rhinovirus-induced colds and other respiratory disorders. Since it is now generally believed that the symptoms of rhinovirus colds are due to the enhanced secretion of inflammatory chemokines and cytokines, we decided to analyze the effects of rhinovirus infection and Echinacea treatment [defined extracts of E. purpurea (L.) Moench] on cytokine/chemokine gene expression and protein secretion in a line of human tracheo- bronchial epithelial cells. Among the collection of more than 50 cytokines and chemokines present in the gene arrays, 12 showed significant induction of expression by the virus (> 2-fold), some of them by more than 5-fold. However, not all of these resulted in similar changes in the corresponding proteins, presumably as a consequence of post-transcriptional changes. A total of 16 cytokines, mostly chemokines, showed substantial protein increases, including several, such as the well known pro-inflammatory cytokines IL-6 and IL-8 (CXCL8), which were induced in the absence of additional transcription. These results support the concept that virus-induced multiple inflammatory cytokines are responsible for the cold symptoms. In most cases, one or both Echinacea preparations reversed the viral stimulation, thus providing a basis for the anti-inflammatory properties attributed to Echinacea. [ABSTRACT FROM AUTHOR]

Echinacea extracts have traditionally been used in the treatment of many infectious and other diseases (such as rhinovirus colds), and research has revealed the presence of various bioactivities in these extracts, particularly those connected with immune responses. We examined the effects of Echinacea by using gene expression analysis in a line of human bronchial epithelial cells, with or without rhinovirus infection. More than 13 000 human genes were evaluated. From these analyses we focused primarily on immune response genes and found that both Echinacea extracts, one predominantly rich in polysaccharides and the other rich in alkylamides and caffeic acid derivatives, stimulated the expression of numerous genes. These included a number of cytokines and chemokines, although the pattern of stimulation was different. In addition, Echinacea extracts tended to neutralize the effects of the rhinovirus. When the immune response gene pathways were analyzed with the Ingenuity Pathway program, it became apparent that many of them were interconnected through a major node, the transcription factor C/EBPβ (CAAT/enhancer-binding protein β) and its related C/EBP proteins. This suggests that Echinacea can bring about important biological responses in cells by virtue of interactions between components of the extract and a small number of intracellular factors involved in multiple signaling pathways. [ABSTRACT FROM AUTHOR]