Reorganization of corticostriatal circuits in healthy G2019S LRRK2 carriers

Rick C. Helmich, Avner Thaler, Bart F.L. Van Nuenen, Tanya Gurevich, Anat Mirelman, Karen S. Marder, Susan Bressman, Avi Orr-Urtreger, Nir Giladi, Bastiaan R. Bloem, Ivan Toni

Research output: Contribution to journalArticlepeer-review

61 Scopus citations

Abstract

Objective: We investigated system-level corticostriatal changes in a human model of premotor Parkinson disease (PD), i.e., healthy carriers of the G2019S LRRK2 mutation that is associated with a markedly increased, age-dependent risk of developing PD. Methods: We compared 37 asymptomatic LRRK2 G2019S mutation carriers (age range 30-78 years) with 32 matched, asymptomatic nonmutation carriers (age range 30-74 years). Using fMRI, we tested the hypothesis that corticostriatal connectivity in premotor PD shifts from severely affected to less affected striatal subregions, as shown previously in symptomatic PD. Specifically, we predicted that in premotor PD, the shift in corticostriatal connectivity would follow the same gradient of striatal dopamine depletion known fromovert PD, with the dorsoposterior putamen being more affected than the ventroanterior putamen. Results: The known parallel topology of corticostriatal loops was preserved in each group, but the topography of putamen connectivity shifted. In LRRK2 G2019S mutation carriers, the right inferior parietal cortex had reduced functional connectivity with the dorsoposterior putamen but increased connectivity with the ventroanterior putamen, as compared with noncarriers. This shift in functional connectivity increased with age in LRRK2 G2019S mutation carriers. Conclusions: Asymptomatic LRRK2 G2019S mutation carriers show a reorganization of corticostriatal circuits that mirrors findings in idiopathic PD. These changes may reflect premotor basal ganglia dysfunction or circuit-level compensatory changes.

Original languageEnglish
Pages (from-to)399-406
Number of pages8
JournalNeurology
Volume84
Issue number4
DOIs
StatePublished - 1 Jan 2015
Externally publishedYes

ASJC Scopus subject areas

  • Clinical Neurology

Fingerprint

Dive into the research topics of 'Reorganization of corticostriatal circuits in healthy G2019S LRRK2 carriers'. Together they form a unique fingerprint.

Cite this