Scientists Liking Lichens as Possible Help for Alzheimer's


You might not give a second glance to lichens clinging to a rock or tree trunk, but this composite of organisms may provide some possible help for managing Alzheimer’s disease. A red dye called orcein that is derived from lichens along with another dye called O4 appear to attach themselves to amyloids, which are believed to play a major contributing role in Alzheimer’s disease, and render them nontoxic.

Could lowly lichens help Alzheimer’s patients?

Lichens are an unusual organism in that they consist of a fungus along with a photosynthetic agent, which is usually a green algae or a cyanobacterium. You can find lichens in just about any environment on the planet, ranging from the extremely cold arctic to the blazing deserts and regions in between.

Lichens have been useful in making dyes and perfumes, and in some traditional medicines. A recent study conducted in Serbia found that certain lichens have potent antibacterial and antifungal properties.

In this latest study, which was conducted by researchers at the Max Delbruck Center (MDC) for Molecular Medicine in Berlin, Germany, investigators have discovered that a blue dye called O4, which is very similar in structure to one of orcein’s 14 molecules, can stimulate the formation of large, nontoxic protein plaques from small, toxic protein structures.


It is commonly believed among the medical community that plaques are involved in the development of Alzheimer’s disease. Plaques are deposits of a protein fragment called beta amyloid that accumulates in the spaces between nerve cells. Although most people develop plaques as they get older, people with Alzheimer’s disease tend to build up many more than normal, and this abnormal accumulation contributes to memory loss and other cognitive problems associated with the disease.

The discovery made in the new study is important because, as Professor Erich Wanker of MDC explained, “If our hypothesis is correct that the small aggregates, which are precursors of plaques, indeed cause neuronal death, with O4 we would have a new mechanism to attack the disease.” Orcein speeds up the formation of large, nontoxic plaques.

Thus far the experiments have been limited to the laboratory, so whether lichens will be beneficial in Alzheimer’s patients is yet to be determined. Professor Wanker noted that he and his colleagues “hope that our findings will stimulate research activities in this direction, especially in drug discovery.”

Max Delbruck Center for Molecular Medicine
Rankovic B et al. Mikrobiologiia 2010 Nov-Dec; 79(6): 812-18

Picture credit: Wikimedia Commons