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L-Serine Reduces Spinal Cord Pathology in a Vervet Model of Preclinical ALS/MND.

ABSTRACT: The early neuropathological features of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND) are protein aggregates in motor neurons and microglial activation. Similar pathology characterizes Guamanian ALS/Parkinsonism dementia complex, which may be triggered by the cyanotoxin ?-N-methylamino-l-alanine (BMAA). We report here the occurrence of ALS/MND-type pathological changes in vervets (Chlorocebus sabaeus; n?=?8) fed oral doses of a dry powder of BMAA HCl salt (210?mg/kg/day) for 140?days. Spinal cords and brains from toxin-exposed vervets were compared to controls fed rice flour (210?mg/kg/day) and to vervets coadministered equal amounts of BMAA and l-serine (210?mg/kg/day). Immunohistochemistry and quantitative image analysis were used to examine markers of ALS/MND and glial activation. UHPLC-MS/MS was used to confirm BMAA exposures in dosed vervets. Motor neuron degeneration was demonstrated in BMAA-dosed vervets by TDP-43+ proteinopathy in anterior horn cells, by reactive astrogliosis, by activated microglia, and by damage to myelinated axons in the lateral corticospinal tracts. Vervets dosed with BMAA + l-serine displayed reduced neuropathological changes. This study demonstrates that chronic dietary exposure to BMAA causes ALS/MND-type pathological changes in the vervet and coadministration of l-serine reduces the amount of reactive gliosis and the number of protein inclusions in motor neurons.

SUBMITTER: Davis DA

PROVIDER: S-EPMC7092359 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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l-Serine Reduces Spinal Cord Pathology in a Vervet Model of Preclinical ALS/MND.

Davis David A DA Cox Paul Alan PA Banack Sandra Anne SA Lecusay Patricia D PD Garamszegi Susanna P SP Hagan Matthew J MJ Powell James T JT Metcalf James S JS Palmour Roberta M RM Beierschmitt Amy A Bradley Walter G WG Mash Deborah C DC

Journal of neuropathology and experimental neurology 20200401 4

The early neuropathological features of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND) are protein aggregates in motor neurons and microglial activation. Similar pathology characterizes Guamanian ALS/Parkinsonism dementia complex, which may be triggered by the cyanotoxin β-N-methylamino-l-alanine (BMAA). We report here the occurrence of ALS/MND-type pathological changes in vervets (Chlorocebus sabaeus; n = 8) fed oral doses of a dry powder of BMAA HCl salt (210 mg/kg/day) for 140 d ...[more]

PMID: 32077471

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Dataset Information

L-Serine Reduces Spinal Cord Pathology in a Vervet Model of Preclinical ALS/MND.

Publications

l-Serine Reduces Spinal Cord Pathology in a Vervet Model of Preclinical ALS/MND.

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