Illustration showing the molecular structure of a Lewy body. Lewy bodies are abnormal aggregations of proteins, disrupted organelles and membrane lipids. Their formation in nerve cells in the brain is associated with the neurodegenerative diseases Parkinsons disease and Lewy body dementia. The proteins in Lewy bodies are mainly alpha-synucleins (yellow) that have formed associations with other proteins such as ubiquitin, neurofilament protein and alpha B crystallin. Microtubules (light orange), vesicles and membrane lipids (dark orange), actin filaments (dark red) and neurofilaments (brown) are other potential components.