Time for echinacea

The hot long days of summer are over and will become a fading memory. The warm golden days and crisp nights are upon us. Children back at school and cold and flu season beckons.

As I ride my bike just north of the Kelowna airport, I see acres of a purple and red daisy flower. I recognize the flower as echinacea, which is grown commercially by a large nutraceutical company. The glint of morning light on the flowerheads is beautiful and stunning.

Echinacea (Echinacea angustifolia and Echinacea purpurea) are two perennial flowering plants native to the Great plains of North America. These species grow from 20 to 100 centimetres in height and have brightly coloured purple or reddish aster flowerheads when in bloom. It is a member of the Asteraceae or daisy family.

Both species were some of the most widely used medicinal plants of the midwestern Indigenous people. They were used to treat toothaches, coughs, colds, sore throats and snakebites and were also used as a pain killer. More recent scientific research, mainly by German researchers, showed echinacea has immune stimulating properties.

Many active ingredients have been identified in echinacea and it appears they work synergistically. Echinacoside is a glycoside, a sugar-linked molecule, comprising about 1% of the dry weight of the plant. It displays mild antibacterial activity.

Echinacin is a polysaccharide, or long-chain sugar molecule, that has immune stimulating and antiviral activity. Echinacin has been shown to consist of two polysaccharide molecules—polysaccharide A and polysaccharide B. It inhibits the activity of the enzyme hyaluronidase which is responsible for the breakdown of connective tissue. This mechanism enhances connective tissue stabilization in the spaces between cells and tissues, thereby preventing the spread and infiltration of foreign microbes. The connective tissue forms a barrier between cells thereby preventing micro-organisms from spreading and decreasing inflammation.

Echinacin B has been shown to combine with hyaluronidase temporarily inactivating it and thus promotes connective tissue integrity. It has also been suggested other constituents in echinacea may be involved in connective tissue stabilization in addition to echinacin.

Echinacea further enhances wound healing by also stimulating connective tissue regeneration. Other ingredients in echinacea stimulate the breakdown of fibrin in clots into polysaccharides, which are then recycled into new connective tissue.

Constituents, including echinacin, stimulate the immune system by enhancing macrophage function. This polysaccharide molecule activates to engulf and destroy invading foreign organisms. In addition, echinacin binds membrane receptors of the surface of T-lymphocytes. That then facilitates the production of intracellular messengers, including interferon and other cytokines which further activate macrophages and natural killer cells.

Ingredients in echinacea further activates the complement pathway of the immune system. The complement pathway involves a complex series of enzymatic reactions in normal blood that uses proteins and antigen antibody complexes. Complement proteins bind antigen antibody complexes which enhances the destruction of foreign material. Echinacin also increases properdin, an enzymatic protein involved in the alternate complement pathway. Echinacin also stimulates a non-specific immune response that increases the function of macrophages, T-lymphocytes and the complement pathway.

Extracts of echinacea have demonstrated antiviral activity against influenza, herpes and vesicular stomatitis viruses. The antiviral activity of these echinacea extracts is believed to be related to the plant’s non-specific immune modulating activity. Furthermore, the connective tissue stabilization and regeneration qualities and direct activation of macrophages and lymphocytes are among the immune stimulating effects of this plant.

Clinically, echinacea has been used to treat various bacteria caused skin infections with good results. Echinacea stimulates production of white blood cells in the bone marrow of patients undergoing radiation therapy. A quick PubMed search of echinacea reveals more than 1,500 studies.

The studies are mixed about the effectiveness of echinacea in treating the common cold. An analysis of studies concluded echinacea may reduce your risk of getting a cold by up to 58% and may shorten its duration by about 1.4 days. Further clinical research into the immune modifying actions of echinacea is necessary to support its traditional use as an immune stimulator.

Echinacea is relatively safe and non-toxic. There appears to be few side effects. Occasional allergic reaction and skin rash have been reported in some people. There appears to be no adverse effects of long-term use.

It’s use in auto-immune disorders has not been shown to deleterious and its benefit for short-term is probably OK. It is safe for children to use but is not generally recommended for children younger than one year of age. It’s use during pregnancy remains questionable.

The information provided in this article does not, and is not intended to constitute medical advice. All information and content are for general information purposes only.

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.