Epigallocatechin found in blackcurrants could reduce the inflammation that is involved in allergic asthma, according to an article published online on March 12, 2010 in the journal Molecular Nutrition and Food Research.
In allergic asthma, long term inflammation occurs in response to allergen exposure in the lungs. Epidemiologic studies have associated increased fruit consumption with a reduction in allergy-induced asthma symptoms, yet a mechanism for fruit had not been determined.
Roger D. Hurst and colleagues at The Plant and Food Research Institute of New Zealand tested a proanthocyanidin-enriched and an anthocyanin-rich New Zealand blackcurrant extract on cultured human alveolar (lung) epithelial cells. Both proanthocyanidins and anthocyanins have antioxidant properties and can reduce inflammation.
The proanthocyanidin rich extract, but not the anthocyanin rich extract, dose-dependently suppressed interleukin-4- and interleukin-13-stimulated secretion of CCL26, which is a factor in the continuous recruitment of eosinophils (a type of white blood cell) that occurs in allergic asthma. Preincubation of the cells with the proanthocyanidin rich extract also suppressed interleukin-4 induced CCL26 secretion. The team determined that epigallocatechin and, to a lesser extent epicatechin metabolites found in the proanthocyanidin rich extract, were responsible for the reduction in inflammation that occurred.
“To find natural compounds that potentially reduce lung inflammation and complement the body’s own immune response is an exciting breakthrough,” stated Dr Hurst. “Should we discover more about how this works we may eventually develop foods containing these compounds that could provide more natural alternatives to assist conventional drug treatments for asthma and even other allergic reactions.”