Effect of methylmercury on fetal neurobehavioral development: an overview of the possible mechanisms of toxicity and the neuroprotective effect of phytochemicals

Arch Toxicol. 2022 Dec;96(12):3175-3199. doi: 10.1007/s00204-022-03366-3. Epub 2022 Sep 5.

Abstract

Methylmercury (MeHg) is a global environmental pollutant with neurotoxic effects. Exposure to MeHg via consumption of seafood and fish can severely impact fetal neurobehavioral development even when MeHg levels in maternal blood are as low as about 5 μg/L, which the mother tolerates well. Persistent motor dysfunctions and cognitive deficits may result from trans-placental exposure. The present review summarizes current knowledge on the mechanisms of MeHg toxicity during the period of nervous system development. Although cerebellar Purkinje cells are MeHg targets, the actions of MeHg on thiol components in the neuronal cytoskeleton as well as on mitochondrial enzymes and induction of disturbances of glutamate signaling can impair extra-cerebellar functions, also at levels well tolerated by adult individuals. Numerous herbal substances possess neuroprotective effects, predominantly represented by natural polyphenolic molecules that might be utilized to develop natural drugs to alleviate neurotoxicity symptoms caused by MeHg or other Hg compounds.

Keywords: Contamination; Herbal compounds; Methylmercury; Neurodevelopment; Neuroprotection; Neurotoxicity.

Publication types

  • Review

MeSH terms

  • Animals
  • Environmental Pollutants* / toxicity
  • Female
  • Glutamates
  • Mercury*
  • Methylmercury Compounds* / toxicity
  • Neuroprotective Agents* / pharmacology
  • Neuroprotective Agents* / therapeutic use
  • Neurotoxicity Syndromes* / etiology
  • Neurotoxicity Syndromes* / prevention & control
  • Phytochemicals
  • Placenta
  • Pregnancy
  • Sulfhydryl Compounds

Substances

  • Methylmercury Compounds
  • Neuroprotective Agents
  • Environmental Pollutants
  • Phytochemicals
  • Sulfhydryl Compounds
  • Mercury
  • Glutamates