Olfactory dysfunction is one of the earliest features in Lewy-type alpha-synucleinopathies (LTS) such as Parkinson´s disease (PD). However, the underlying molecular mechanisms associated to smell impairment is poorly understood. To reveal the missing links in the biochemical understanding of olfactory dysfunction in PD, we have applied mass spectrometry-based proteomics in postmortem olfactory bulbs (OBs) dissected from parkinsonian subjects with different LTS staging respect to elderly controls (n= 24, mean age 79 years).