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Methylene blue and monosodium glutamate improve neurologic signs after fluoroacetate poisoning.

ABSTRACT: Fluoroacetate (FA) is a tasteless, odorless, water-soluble metabolic poison with severe toxicological effects. Characterized in the mid-1900s, it has been used as a rodenticide but is comparably lethal to all mammals. Many countries have restricted its use, and modern-day accidental human exposures are rare, but recently, concerns have been raised about its application as a chemical weapon with no known antidote. A combined treatment of methylene blue (MB), an antioxidant, and monosodium glutamate (MSG), a precursor of the citric acid cycle substrate alpha-ketoglutarate, has been recommended as an effective countermeasure; however, no peer-reviewed articles documenting the efficacy of this therapy have been published. Using a rodent model, we assessed the effects of MB and MSG on the neurologic, cardiac, and pulmonary systems. Transcriptomic analysis was used to elucidate inflammatory pathway activation and guide bioassays, which revealed the advantages and disadvantages of these candidate countermeasures. Results show that MB and MSG can reduce neurologic signs observed in rats exposed to sodium FA and improve some effects of intoxication. However, while this strategy resolved some signs of intoxication, ultimately it was unable to significantly reduce lethality.

SUBMITTER: DeLey Cox VE

PROVIDER: S-EPMC7554062 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Methylene blue and monosodium glutamate improve neurologic signs after fluoroacetate poisoning.

DeLey Cox Vanessa E VE Hartog Matthew A MA Pueblo Erin E Racine Michelle M Jennings Laura L Tressler Justin J Tuet Wing Y WY Stone Samuel S Pierce Samuel A SA Thompson Lily L Dukes Aliyah A Hoard-Fruchey Heidi H Wong Benjamin B McCranor Bryan J BJ

Annals of the New York Academy of Sciences 20200414 1

Fluoroacetate (FA) is a tasteless, odorless, water-soluble metabolic poison with severe toxicological effects. Characterized in the mid-1900s, it has been used as a rodenticide but is comparably lethal to all mammals. Many countries have restricted its use, and modern-day accidental human exposures are rare, but recently, concerns have been raised about its application as a chemical weapon with no known antidote. A combined treatment of methylene blue (MB), an antioxidant, and monosodium glutama ...[more]

PMID: 32285953

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Methylene blue and monosodium glutamate improve neurologic signs after fluoroacetate poisoning.

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Methylene blue and monosodium glutamate improve neurologic signs after fluoroacetate poisoning.

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