Plants Causing Toxic Myopathies

Beatrice Sponseller; Tim Evans

doi:10.1016/j.cveq.2023.11.001

Plants Causing Toxic Myopathies

Vet Clin North Am Equine Pract. 2024 Apr;40(1):45-59. doi: 10.1016/j.cveq.2023.11.001. Epub 2023 Dec 26.

Authors

Beatrice Sponseller¹, Tim Evans²

Affiliations

¹ Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, 1809 South Riverside Drive, Ames, IA 50011, USA. Electronic address: beatrice@iastate.edu.
² Department of Biomedical Sciences, College of Veterinary Medicine and MU Extension, University of Missouri, W226 Veterinary Medicine Building, 1520 East Rollins Street, Columbia, MO 65211, USA.

PMID: 38151404
DOI: 10.1016/j.cveq.2023.11.001

Abstract

Boxelder and sycamore maple contain hypoglycin A (HGA), the toxic metabolite of which, MCPA-CoA, inhibits fatty acid β-oxidation, causing seasonal pasture myopathy (SPM) or atypical myopathy (AM), respectively. White snakeroot and rayless goldenrod contain multiple benzofuran ketones (BFKs). The identity/toxicity of BFKs appear variable, possibly involving interactions between toxins/toxic metabolites, but ultimately inhibit cellular energy metabolism. Unthrifty horses grazing sparse pastures during the fall appear predisposed to these plant-associated, frequently fatal, toxic myopathies. Toxidromes are characterized by varying degrees of rhabdomyolysis and cardiac myonecrosis, with plant toxins remaining toxic in hay and being excreted in milk.

Keywords: Benzofuran ketones; Boxelder and sycamore maple; Cardiomyopathy; Hypoglycin A; Rayless goldenrod; Toxic myopathy; Tremetol/tremetone; White snakeroot.

Publication types

Review

MeSH terms

Animals
Horse Diseases* / chemically induced
Horses
Muscular Diseases* / chemically induced
Muscular Diseases* / veterinary
Myotoxicity / veterinary
Plant Poisoning* / veterinary
Plants, Toxic