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Plant poisoning leads to alpha-synucleinopathy and neuromelanopathy in kangaroos.

ABSTRACT: The pathogenesis of synucleinopathies, common neuropathological lesions normally associated with some human neurodegenerative disorders such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, remains poorly understood. In animals, ingestion of the tryptamine-alkaloid-rich phalaris pastures plants causes a disorder called Phalaris staggers, a neurological syndrome reported in kangaroos. The aim of the study was to characterise the clinical and neuropathological changes associated with spontaneous cases of Phalaris staggers in kangaroos. Gross, histological, ultrastructural and Immunohistochemical studies were performed to demonstrate neuronal accumulation of neuromelanin and aggregated α-synuclein. ELISA and mass spectrometry were used to detect serum-borne α-synuclein and tryptamine alkaloids respectively. We report that neurons in the central and enteric nervous systems of affected kangaroos display extensive accumulation of neuromelanin in the perikaryon without affecting neuronal morphology. Ultrastructural studies confirmed the typical structure of neuromelanin. While we demonstrated strong staining of α-synuclein, restricted to neurons, intracytoplasmic Lewy bodies inclusions were not observed. α-synuclein aggregates levels were shown to be lower in sera of the affected kangaroos compared to unaffected herd mate kangaroos. Finally, mass spectrometry failed to detect the alkaloid toxins in the sera derived from the affected kangaroos. Our preliminary findings warrant further investigation of Phalaris staggers in kangaroos, potentially a valuable large animal model for environmentally-acquired toxic synucleinopathy.

SUBMITTER: Tayebi M

PROVIDER: S-EPMC6853926 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Plant poisoning leads to alpha-synucleinopathy and neuromelanopathy in kangaroos.

Tayebi Mourad M El-Hage Charles M CM Pinczowski Pedro P Whiteley Pam P David Monique M Li Qiao-Xin QX Varghese Shiji S Mikhael Meena M Habiba Umma U Harman David D Tatarczuch Liliana L Bogeski Mirjana M Birchall Ian I Ferguson Kirsty K Walker Larry L Masters Colin C Summers Brian A BA

Scientific reports 20191113 1

The pathogenesis of synucleinopathies, common neuropathological lesions normally associated with some human neurodegenerative disorders such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, remains poorly understood. In animals, ingestion of the tryptamine-alkaloid-rich phalaris pastures plants causes a disorder called Phalaris staggers, a neurological syndrome reported in kangaroos. The aim of the study was to characterise the clinical and neuropathological changes ...[more]

PMID: 31723225

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Dataset Information

Plant poisoning leads to alpha-synucleinopathy and neuromelanopathy in kangaroos.

Publications

Plant poisoning leads to alpha-synucleinopathy and neuromelanopathy in kangaroos.

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