LewyKörper

LewyKörper, commonly referred to as Lewy body, denotes abnormal intraneuronal inclusions found in certain neurodegenerative diseases. They are primarily composed of misfolded alpha-synuclein, a presynaptic protein, and often contain ubiquitin and other components. Lewy bodies stain eosinophilic with standard light microscopy and can be labeled with antibodies against alpha-synuclein to confirm their presence in tissue.

The term honors Friedrich Lewy, who first described such inclusions in the substantia nigra of patients with Parkinson's disease in 1912. In German-language literature, the term Lewy-Körperchen is frequently used; in English, Lewy body is the standard designation.

Lewy bodies are a major pathological hallmark of Parkinson's disease (PD) and dementia with Lewy bodies (DLB). In PD, they typically begin in the brainstem, especially the substantia nigra, and progressively involve limbic and cortical regions as the disease advances. In DLB, cortical Lewy bodies are prominent and contribute to early cognitive impairment and fluctuations. Lewy bodies may also be found in incidental Lewy body disease, where pathology is present without overt parkinsonism.

Pathophysiology: Aggregation of alpha-synuclein disrupts cellular proteostasis, mitochondrial function, and synaptic transmission. The regional distribution of Lewy bodies correlates with clinical features, and Braak staging describes a hypothetical progression from brainstem to cortex.

Diagnosis and research: Definitive confirmation requires postmortem examination. Antemortem biomarkers under investigation include alpha-synuclein assays in cerebrospinal fluid or peripheral tissues and dopaminergic imaging; these tools aid differential diagnosis and monitoring. Therapeutic approaches increasingly target alpha-synuclein aggregation and its spread.